CN104903553B - Exploitation for the conversion roller finger follower that the cylinder in internal combustion engine is closed down - Google Patents

Abstract

Disclose a kind of system of the engine valve of cylinder for internal combustion engine of selectively closing down.The system is between engine valve and rotation nose using conversion rocker arm assembly.The design can be worked with each valve using single nose.The rocker arm assembly is first using the first arm being attached on the second arm pivotally at one end.First arm is engaged with valve, and the second arm has the roller bearing engaged with nose.Lock bolt causes the first and second arms to follow cam face integrally mobile in locking.When unlocked, the second arm is according to rotary cam surface with amiable movement, but the first arm does not follow and do not operate valve, cylinder of thus closing down.

Description

Exploitation for the conversion roller finger follower that the cylinder in internal combustion engine is closed down

Cross-reference to related applications

This application claims " DEVELOPMENT OF A SWITCHING ROLLER submitting, entitled on November 5th, 2012 FINGER FOLLOWER FOR CYLINDER DEACTIVATION IN GASOLINE ENGINE APPLICATIONS (is used The exploitation of conversion roller finger follower that cylinder in petrol engine application is closed down) " U.S. Provisional Patent Application system The equity of row number 61/722,765 (EATN-0111-P01).

The application is also that the part of following application continues: the U.S. Non-provisional Patent series number that on June 25th, 2012 submits 13/532,777；The U.S. Non-provisional Patent series number 13/051,839 that on March 18th, 2011 submits；With on March 18th, 2011 The U.S. Patent application 13/051,848 of submission.

U.S. Non-provisional Patent application 13/532,777 is that on August 13rd, the 2010 application No.12/856,266 submitted are (existing For the continuity of patent No.8,215,275).

The application is also that the part of following U.S. Non-provisional Patent application serial no continues: 13/868,249 (EATN- 0201-U01)；13/868,035(EATN-0201-U01-C01)；13/868,045(EATN-0202-U01)；13/868,054 (EATN-0202-U01-C01)；13/868,061(EATN-0206-U01)；13/868,067(EATN-0209-U01)；With 13/ 868,068 (EATN-0210-U01), these applications are all submitted on April 22nd, 2013.

The application is also U.S. Non-provisional Patent application serial no 13/873,774 (EATN-0207-U01) and 13/873, The part of 797 (EATN-0208-U01-C01) continues, the two applications are submitted on April 30th, 2013.

The application be also following international pct application part continue: PCT/US2013/037667 (EATN-0204-WO) and PCT/US2013/037665 (EATN-0206-WO), the two applications were submitted on April 22nd, 2013, and at 2013 4 The PCT/US2013/038896 (EATN-0210-WO) that the moon is submitted on the 30th.

U.S. non-provisional application series number 13/868,249 (EATN-0201-U01), 13/868,035 (EATN-0201- U01-C01)、13/868,045(EATN-0202-U01)、13/868,054(EATN-0202-U01-C01)、13/868,061 (EATN-0206-U01), 13/868,067 (EATN-0209-U01) and 13/868,068 (EATN-0210-U01) are all required The equity of following U.S. Provisional Patent Application Serial number: the 61/636,277 (EATN- all submitted on April 20th, 2012 0205-P01)、61/637,786(EATN-0206-P01)、61/640,709(EATN-0209-U01)、61/640,713 (EATN-0210-U01), 61,777,769 (EATN-0202-P01) and on March 1st, 2013 submitted.

U.S. non-provisional application series number 13/868,249 (EATN-0201-U01), 13/868,035 (EATN-0201- U01-C01)、13/868,045(EATN-0202-U01)、13/868,054(EATN-0202-U01-C01)、13/868,061 (EATN-0206-U01), 13/868,067 (EATN-0209-U01) and 13/868,068 (EATN-0210-U01) is following beauty The part of state's patent application Ser. No continues: on March 18th, 2011 submit 13/051,839 and mention on March 1st, 2011 13/051,848 handed over.

U.S. non-provisional application series number 13/873,774 (EATN-0207-U01), 13,873,979 (EATN-0208- U01) require the equity of following U.S. Provisional Patent Application Serial number: all on April 20th, 2012 submit 61/636,277 (EATN-0205-P01)、61/637,786(EATN-0206-P01)、61/640,705(EATN-0207-U01)、61/640, 707 (EATN-0208-U01), 61/640,709 (EATN-0209-U01), 61/640,713 (EATN-0210-U01), Yi Ji 61,777,769 (EATN-0202-P01) that on March 1st, 2013 submits.

U.S. non-provisional application series number 13/873,774 (EATN-0207-U01)；13,873,979(EATN-0208- U01) be following U.S. Patent Application Serial part continue application: in 13/051,839 He that on March 18th, 2011 submits On March 1st, 2011 submit 13/051,848.

Technical field

This application involves be used to internal combustion engine and be more specifically for more effectively novel variable valve-operating conversion shake The rocker design of arm system.

Background technique

With increased fuel consumption and greenhouse gas emission, global rising cost of energy and to lower operation at This related global environment of demand and economic worry are promoting the transformation of legal regulations and consumer demand.With these rule Chapter and demand become tightened up, it is necessary to develop and implement advanced engine technology to realize desired benefit.

Figure 1B shows several valve mechanism arragement constructions used now.In (22) two kinds of arrangement knots of I type (21) and II type In structure, the camshaft with one or more air door operation peach tips 30 is located at 29 top (overhead cam) of engine valve.In I type (21) in valve mechanism, overhead cam peach tip 30 directly drives valve through hydraulic valve clearance adjuster (HLA) 812.In II type (22) in valve mechanism, overhead cam peach tip 30 drives rocker arm 25, and the first end of rocker arm pivots on HLA 812, and second End operation valve 29.

In type III (23), the first end of rocker arm 28 is rided upon on nose 30 and is positioned above, and rocker arm 28 Second end operates valve 29.As nose 30 rotates, rocker arm is pivoted around fixed axis 31.HLA 812 can be in valve Implement between head 29 and rocker arm 28.

In V-type (24), nose 30 drives the first end of rocker arm 26 using push rod 27 indirectly.HLA 812 is shown To implement between nose 30 and push rod 27.The second end of rocker arm 26 operates valve 29.As nose 30 rotates, shake Upper-arm circumference is pivoted around fixed axis 31.

As Figure 1A is also shown, it is contemplated that as shown in the percentage of whole market to the II type (22) in automobile engine The industry prediction of valve mechanism is the most common configuration of production in 2019.

Introducing the technology for being absorbed in II type (22) valve mechanism --- it is by reducing friction loss, pump suction loss and heat Lose to improve the whole efficiency of petrol engine --- most preferably to utilize in-engine fuel.These variable valve-operatings (VVA) a part among technology has been incorporated into and is described in the literature.

VVA device can be lift range variable (VVL) system, be such as incorporated to by reference of text herein in 2012 years U.S. Patent application No.13/532,777 " rocker arm of closing down (the Single Lobe of single peach tip that June 25 submitted Deactivating Rocker Arm) " described in cylinder close down (CDA) system or other valve operating systems.Such as meaning Out, these mechanisms are developed to improve the performance of engine, fuel economy and/or reduce its discharge.A few class VVA rocking arm sets Part includes the inner rocker arm in outer rocker arm, and the outer rocker arm and inner rocker arm are biased in together using torque spring.Lock bolt is being located Move integrally both inner rocker arm and outer rocker arm when latched position.When unlocked, rocker arm is allowed to move independently of one another.

Conversion rocker arm allows to control air door operation by replacing between lock state and unlocked state, generally includes Inner arm and outer arm as described above.In some cases, these arms lift peach tip for example low from different noses, high lift peach Point and without lift peach tip engage.Need the mechanism for converting rocker arm mode in a manner of being suitble to the operating of internal combustion engine.

For change the operating of II type petrol engine and improve its fuel economy VVA technology an example be from It dissipates lift range variable (DVVL), otherwise referred to as DVVL converts rocker arm.DVVL is by using engine air door restrict engine Cylinder intake air flow and work, the engine valve utilize discrete valve lift state and standard " part-throttle " relationship. Second example is that cylinder closes down (CDA).It can be by selecting the higher combustion cylinders of load using CDA in part load condition It works and closes other cylinders to improve fuel economy.

Environmental Protection Agency (EPA) confirms fuel economy when using the DVVL for being applied to various passenger vehicle engines Property improves 4%.The relatively early report that U.S. Department of Energy is initiated lists the benefit that fuel economy is improved 4.5% by DVVL.By " part-throttle " during automobile is mostly in usually cruise operating, so reducing the loss of these throttles to the maximum extent When may be implemented significantly fuel economy raising.For CDA, studies have shown that considering to be attributed to the secondary of the cylinder closed down After loss, the fuel economy benefit between 2% and 14% is realized.

It is desirable to more effectively operation and with existing rocker design compared with increased ability VVA system with Device.

Summary of the invention

Advanced VVA system for piston internal-combustion engine combines valve stroke control device such as CDA or DVVL Conversion rocker arm, valve lift operation method such as use the hydraulic operation of pressurized engine oil, software and hardware control system and Improving technology.Improving technology may include sensing and instrumentation, OCV design, DFHLA design, torque spring, specific coatings, algorithm Deng.

In one embodiment, describe a kind of advanced discrete variable valve stroke (DVVL) system, this it is advanced from Lift range variable (DVVL) system of dissipating is designed to provide two kinds of discrete valve lift states in single rocker arm.The side proposed The II type valve mechanism that the embodiment of case is related to above description and shows in fig. ib.The embodiment of system proposed in this paper can answer For with electro-hydraulic oil control valve, double-fed type hydraulic valve gap (lash) adjuster (DFHLA) and DVVL conversion rocker arm Passenger vehicle engine (has 4 cylinders) in embodiment.DVVL conversion rocker arm embodiment described herein is absorbed in conversion In the design and exploitation of roller finger follower (SRFF) rocker arm system, the rocker arm system is driven in end pivot roller finger Double mode discrete variable valve stroke is realized on part valve mechanism.The conversion rocker arm configuration includes rubbing for the low of low lift events Roller bearing interface is wiped, and keeps common hydraulic valve gap adjustment to maintain free valve mechanism to operate.

Mode conversion (that is, from low lift to high lift, or vice versa) is turn-taked interior completion in a cam, to make driver It is clear.SRFF prevents the significant change for being mounted on headspace needed for existing engine design.At cam interface Load-bearing surface may include for low lift operating roller bearing and for high lift operating be coated with class bore carbon slide block pad. Among other things, teachings of the present application can reduce quality and the moment of inertia while increasing rigidity, in low lift and height Desired dynamic property is realized under lift mode.

Class, which bores carbon coating (DLC coating), allows higher slide block pad interfacial stress in compact package.Test result shows this Technically reliable and meet all life requirements, some of aspects extend to 6 times of service life requirement.Screening alternative materials And surface treatment method, and the result shows that DLC coating is most viable alternative solution.Present application addresses in DVVL in order to convert The technology that carbon (DLC) coating is bored using class in the slide block pad of rocker arm and is developed.

System verification test result discloses the system and meets dynamic and life requirement.Among other things, this patent Application also solves the durability of the design of the SRFF for meeting passenger car life requirement.For high speed, low speed, conversion and cold Starting operation has carried out a large amount of durability tests.High engine speed test result confirms steady on 7000 engine rpm Determine valve mechanism dynamic property.System is wear-resisting to be required to meet for converting, sliding, roll and the end-of-life at torque spring interface Standard.One key criteria of evaluation abrasion is to monitor the variation of valve clearance.Gap, which changes, to be shown to the life requirements of abrasion In acceptable window.Mechanical aspects all play reliable performance in all tests, including bore carbon (DLC) coating comprising class Slide block pad interface.

Using flexible and compact encapsulation, which can implement in multiple cylinder engine.DVVL arragement construction It can be applied to any combination of the inlet valve or exhaust valve in piston driven internal combustion engine.Improving technology include OCV, DFHLA, DLC coating.

In a second embodiment, a kind of advanced single peach tip cylinder is described to close down (CDA-1L) system.The advanced gas Cylinder (CDA-1L) system of closing down is designed to one or more cylinders of closing down.The embodiment of the scheme proposed be related to above description and The II type valve mechanism being shown in FIG. 22.The embodiment of system proposed in this paper can be applied to electro-hydraulic oil control valve, The passenger vehicle engine of double-fed type hydraulic lash (lash) adjuster (DFHLA) and CDA-1L conversion rocker arm (has in embodiment There are multiple cylinders, such as 2,6,8).CDA-1L described herein conversion rocker arm embodiment be absorbed in conversion roller finger with In the design and exploitation of moving part (SRFF) rocker arm system, the rocker arm system is directed to end pivot roller finger driven member valve machine Structure realization lift/without lift operation.The conversion rocker arm configuration includes the low friction roller bearing interface of event of closing down for cylinder, And common hydraulic valve gap adjustment is kept to maintain free valve mechanism to operate.

The mode conversion of CDA-1L system is turn-taked interior completion in a cam, so that driver be made to understand.SRFF prevents from pacifying The significant change of the headspace needed for the existing engine design.Among other things, teachings of the present application Quality and the moment of inertia can be reduced, while increasing rigidity to realize desired dynamic under lift and without lift mode Energy.

CDA-1L system verification test result discloses the system and meets dynamic and life requirement.Among other things, Present patent application also solves meet passenger car life requirement needed for SRFF design durability.For high speed, low speed, turn It changes and has carried out a large amount of durability tests with cold start operating.High engine speed test result confirm 7000 engine rpm it On stabilization valve mechanism dynamic property.System is wear-resisting to be required to meet for converting, rolling and the service life at torque spring interface knot Beam standard.One key criteria of evaluation abrasion is to monitor the variation of valve clearance.Gap, which becomes, to be shown to the life requirements of abrasion Change in acceptable window.Mechanical aspects all play reliable performance in all tests.

Using flexible and compact encapsulation, which can implement in multiple cylinder engine.Improving technology packet Include OCV, DFHLA and the design of special torque spring.

Describe a kind of for engaging the rocker arm of cam, the cam has one lift peach tip of each valve.The rocker arm Including outer arm, inner arm, pivot, lift peach tip contact bearing, bearing axis and at least one bearing axis spring.Outer arm has the first He Second outer webs and it is configured to outer pivot aperture for installing pivot.Inner arm is arranged between the first and second outer webs, And there are the first inner webs and the second inner webs.First and second inner webs have the interior pivot aperture received and keep pivot, And the inner bearing shaft aperture for installing bearing axis.

Pivot cooperates in interior pivot aperture and outer pivot aperture.

Bearing axis is mounted in the bearing shaft aperture of inner arm.

Bearing axis spring be fixed on outer arm and with bearing axis biased contact.Lift peach tip contact bearing is first and second It is mounted between inner webs on bearing axis.

Another embodiment can be described as a kind of for engaging the rocker arm of cam, and the cam has each engine valve Single lift peach tip.The rocker arm includes outer arm, inner arm, is constructed to be permeable to for movement being transmitted to from the single lift peach tip of cam The cam contact component and at least one biasing spring of rocker arm.

The rocker arm further includes the first outer webs and the second outer webs.

Inner arm is arranged between the first and second outer webs, and has the first inner webs and the second inner webs.

Inner arm is described to be configured to the rotation for allowing inner arm around the pivot relative to outer arm by being pivotally secured on outer arm Movement.

Cam contact component is arranged between the first and second inner webs.

At least one biasing spring is fixed on outer arm and contacts with cam contact element biases.

Another embodiment can be described as it is a kind of for engage with single lift peach tip cam rocker arm of closing down, this stops Rocker arm is closed to have a first end and a second end, outer arm, inner arm, pivot, be configured to movement will be transmitted from cam lift peach tip To the lift peach tip contact component of rocker arm, the lock bolt and at least one biasing spring of the rocker arm that is constructed to be permeable to selectively to close down.

Outer arm has the first outer webs and the second outer webs, is configured to the outer pivot aperture and axial trough for installing pivot, The axial trough is configured to receive lift peach tip contact component, to allow the lost motion of lift peach tip contact component mobile.

Inner arm is arranged between the first and second outer webs, and has the first inner webs and the second inner webs.First inside Arm and the second inner webs have the interior pivot aperture being configured to for installing pivot and are configured to for installing the contact of lift peach tip The interior lift peach tip contact component aperture of component.

It is pivotally mounted in the first end of rocker arm nearby and is arranged in interior pivot aperture and outer pivot aperture.

Lock bolt is arranged near the second end of rocker arm.

Lift peach tip contact component is mounted in the lift peach tip contact component aperture of inner arm and the axial trough of outer arm and pivot Between axis and lock bolt.

Biasing spring be fixed on outer arm and with lift peach tip contact component biased contact.

Detailed description of the invention

It will be appreciated that the range of components shown in the drawings only indicates an example of the range.This field it is common Technical staff will be appreciated that discrete component may be designed to multiple element or multiple element may be designed to discrete component.As interior The implementable element that portion's feature is shown is surface, and vice versa.

In addition, in the accompanying drawings and the description below, identical components are in all attached drawings and description with identical attached Icon is remembered to indicate.Attached drawing is not necessarily to scale, and the ratio of certain parts is exaggerated to show.

Figure 1A shows the relative percentage of 2012 and 2019 engine types.

Figure 1B shows the general arragement construction and market scale of I type, II type, type III and V-type valve mechanism.

Fig. 2 shows intake and exhaust valves arrangement of mechanism structures.

Fig. 3 shows the main member including DVVL system, and the DVVL system includes hydraulic operation.

Fig. 4 shows the perspective view for the exemplary transformation rocker arm that can be configured to using three peach tips cam-operated period.

Fig. 5 is the camshaft song shown relative to exemplary DVVL embodiment for both intake and exhaust valves The figure of valve lift state shown in handle angle.

Fig. 6 is the System Control Figure of the DVVL rocker arm assembly for hydraulic operation.

Fig. 7 shows rocker arm oil duct and control valve gear.

Fig. 8 shows the shape of hydraulic operating system and exemplary DVVL conversion rocker arm system during low lift (unlock) operation State.

Fig. 9 shows the shape of hydraulic operating system and exemplary DVVL conversion rocker arm system during high lift (locking) operation State.

Figure 10 shows the side, sectional of the exemplary transformation rocker arm assembly with double-fed type hydraulic lash adjuster (DFHLA) Figure.

Figure 11 is the cross-sectional view of DFHLA.

Figure 12 shows class and bores carbon coating.

Figure 13 shows the position for sensing DFHLA bulb stopper or the instrument of relative movement.

Figure 14 is shown in conjunction with valve stem for measuring the instrument of the valve movement relative to known state.

Figure 14 A and 14B, which are shown using three windings, measures the first mobile linear variable difference transformer of valve stem Cross-sectional view.

Figure 14 C and 14D, which are shown using two windings, measures the second mobile linear variable difference transformer of valve stem Cross-sectional view.

Figure 15 shows another perspective view of exemplary transformation rocker arm.

Figure 16 shows the instrument for being designed to sensing the feedback of position and/or movement.

Figure 17 is to show transition period OCV operation electric current between high lift state and low lift condition, operation oil pressure The curve graph of relationship between valve lift state.

Figure 17 A is the song of the relationship between the OCV operation electric current for showing lock bolt transition period, operation oil pressure and lock bolt state Line chart.

Figure 17 B is the relationship between the OCV operation electric current for showing another lock bolt transition period, operation oil pressure and lock bolt state Curve graph.

Figure 17 C is the pass shown between the valve lift profile for high lift state and low lift condition and operation oil pressure The curve graph of system.

Figure 18 is the control logic figure for DVVL system.

Figure 19 shows the exploded view of exemplary transformation rocker arm.

Figure 20 is to show oil pressure conditions and oil control valve for two kinds of operations of low lift and high lift of DVVL rocker arm assembly (OCV) figure of state.

Figure 21-22 shows the curve graph of display oil temperature and the relationship between the lock bolt response time.

Figure 23 is the time diagram for showing the available conversion window of exemplary DVVL conversion rocker arm in 4 Cylinder engines, wherein grasping Make oil pressure to be controlled by the OCV for controlling two cylinders.

Figure 24 is the side sectional view of DVVL conversion rocker arm, and the lock bolt shown before being transformed into low lift from high lift is pre- Load.

Figure 25 is the side sectional view of DVVL conversion rocker arm, and the lock bolt shown before being transformed into high lift from low lift is pre- Load.

Figure 25 A is the side sectional view of DVVL conversion rocker arm, shows when converting between low lift and high lift critical turn Change event.

Figure 26 is the mechanical switch for showing the available conversion window of exemplary DVVL conversion rocker arm and composition in 4 Cylinder engines The expansion time figure of time, wherein operation oil pressure is controlled by the OCV for controlling two cylinders.

Figure 27 shows the perspective view of exemplary transformation rocker arm.

Figure 28 shows the view from top to bottom of exemplary transformation rocker arm.

Figure 29 shows the sectional view of the interception of the line 29-29 in Figure 28.

Figure 30 A-30B shows the cross-sectional view of exemplary torque spring.

Figure 31 shows the bottom perspective view of outer arm.

Figure 32 shows the sectional view of line 32,33-32,33 of the locking mechanism in its latched position in Figure 28.

Figure 33 shows the sectional view of the locking mechanism in its unlocked state.

Figure 34 shows substitution latch pin design.

Figure 35 A-35F shows several holding meanss for positioning pin.

Figure 36 shows exemplary latch pin design.

Figure 37 shows substitution locking mechanism.

Figure 38-40 shows the illustrative methods of assembling conversion rocker arm.

Figure 41 shows the alternate embodiment of pin.

Figure 42 shows the alternate embodiment of pin.

Figure 43 shows the various gap measurements of conversion rocker arm.

Figure 44 shows the perspective view of the exemplary inner arm of conversion rocker arm.

Figure 45 shows the perspective view of the inner arm of conversion rocker arm seen from below.

Figure 46 shows the perspective view of the exemplary outer arm of conversion rocker arm.

Figure 47 shows the cross-sectional view of the latch assembly of exemplary transformation rocker arm.

Figure 48 is the curve graph in the gap for converting rocker arm and the relationship of camshaft angle.

Figure 49 shows the side sectional view of exemplary transformation rocker arm assembly.

Figure 50 shows the perspective view of the outer arm with the maximum defluxion region identified when under load condition.

Figure 51 shows the top view of exemplary transformation rocker arm and three peach tip cams.

Figure 52 shows the cross-sectional view of the line 52-52 along Figure 51 of exemplary transformation rocker arm.

Figure 53 shows the exploded view of exemplary transformation rocker arm, it is shown that influences the master of the inertia of exemplary transformation rocker arm assembly Want component.

Figure 54 shows the design process of the inertia for optimizing exemplary transformation rocker arm assembly and the relationship between rigidity.

Figure 55 shows the characteristic pattern of the relationship of inertia and rigidity for the design iteration of exemplary transformation rocker arm assembly.

Figure 56 shows the spy of stress, amount of deflection, load and the rigidity of display example conversion rocker arm assembly and the relationship of position Sign figure.

Figure 57 shows the characteristic pattern that inertia and rigid relationship are shown for the range of exemplary transformation rocker arm assembly.

Figure 58 shows the tolerance interval of the rigidity of the component of multiple DVVL conversion rocker arm assemblies and the discrete value of inertia.

Figure 59 be include DFHLA and valve exemplary transformation rocker arm assembly side sectional view.

Figure 60 shows the spy that the range of values of stiffness and the relationship of position are shown for the component of exemplary transformation rocker arm assembly Sign figure.

Figure 61 shows the range for the component display Mass Distribution value of exemplary transformation rocker arm assembly and the relationship of position Characteristic pattern.

Figure 62 shows the testing stand of measurement latch displacement.

Figure 63 is the diagram of the non-ignition testing stand for test conversion rocker arm assembly.

Figure 64 is the curve graph of the relationship of valve displacement and camshaft angle.

Figure 65 shows the level of the Key experiments of the durability for converting roller finger follower (SRFF) rocker arm assembly.

Figure 66 shows the test protocols that assessment SRFF is recycled to acceleration system degradation.

Figure 67 is the pie chart for showing the opposite testing time of SRFF durability test.

Figure 68 shows the deformeter for being mounted on SRFF and monitoring SRFF dduring test.

Figure 69 is the curve graph of the valve-closing rate under low lift mode.

Figure 70 is the distribution of valve falling head.

Figure 71 shows distribution of the critical transitions about camshaft angle.

Figure 72 shows the end of new outer arm before the use.

Figure 73 shows the typical wear of outer arm after usage.

Figure 74 shows the average torque spring load loss in end-of-life test.

Figure 75 shows the overall mechanical gap variation of acceleration system degradation.

Figure 76 shows the slide block pad that the end-of-life with DLC coating of bottom line abrasion is presented.

Figure 77 is using crown camshaft surface embodiment.

Figure 78 shows a pair of of slide block pad in the support arm being mounted on test piece (test coupon).

Figure 79 A shows the DLC coating loss in advance in template test.

Figure 79 B shows the typical case of one of template tested with 0.2 degree of angle in maximum planned load.

Figure 80 is the song for the relationship of the stress level and engine life of the test of the test piece with DLC coating Line chart.

Figure 81, which is directed to, before being coated with DLC coating there is the slide block pad of polishing and non-polished surface to show the engine longevity The increased curve graph of life.

Figure 82 is the flow chart for showing with testing simultaneous manufacture grinding and the exploitation of polishing process.

Figure 83 shows slide block pad angle control result to three different abrasive machines.

Figure 84 shows Surface finish measurement result for three different abrasive machines.

Figure 85 shows the result that six different fixation devices keep outer arm during slide block pad grinding operation.

Figure 86 is the curve graph of the valve-closing rate under high lift mode.

Figure 87 shows durability test circulation.

Figure 88 shows the perspective view of illustrative CDA-1L layout.

Figure 89 A shows the side of the partial sectional of the illustrative SRFF-1L system with latch mechanism and roller bearing Depending on elevation.

Figure 89 B shows the front elevation view of the illustrative SRFF-1L system of Figure 89 A.

Figure 90 is to show the distribution engine of the illustrative SRFF-1L rocker arm assembly on exhaust valve and inlet valve.

Figure 91 shows hydraulic fluid control system.

Figure 92 shows the illustrative SRFF-1L system in the work that usual lift engine valve operation is presented.

Figure 93 A, 93B and 93C show the illustrative SRFF-1L presented in the work without lift engine valve operation System.

Figure 94 shows illustrative conversion window.

Figure 95 shows the influence of the fixed opposite conversion window of camshaft.

Figure 96 shows the lock bolt response time for one embodiment of SRFF-1L system.

Figure 97 is the song shown for illustrative SRFF-1L system in 40 degrees Celsius or more of conversion window time Line chart.

Figure 98 is that camshaft is fixed mutually and the conversion window of oil temperature the considerations of show for illustrative SRFF-1L system The curve graph of time.

Figure 99 shows illustrative SRFF-1L rocker arm assembly.

Figure 100 shows the exploded view of the illustrative SRFF-1L rocker arm assembly of Figure 99.

Figure 101 shows the side view of the illustrative SRFF-1L rocker arm assembly including DFHLA, valve stem and nose Figure.

Figure 102 shows the end view of the illustrative SRFF-1L rocker arm assembly including DFHLA, valve stem and nose Figure.

The lock bolt that Figure 103 shows in the case where the pressure loss rejoins feature.

Figure 104 shows the camshaft alignment of illustrative SRFF-1L system.

Figure 105 shows the power acted on the RFF using hydraulic lash adjuster.

Figure 106 shows the dynamic balance for the illustrative SRFF-1L system under " no lift " mode.

Figure 107 is to show the table of the oil pressure requirement for illustrative SRFF-1 system.

Figure 108 shows the mechanical clearance for illustrative SRFF-1 system.

Figure 109 shows the camshaft lift profile for three peach tip CDA systems and illustrative SRFF-1L system.

Figure 110 is the graphical representation for the rigidity of a variety of rocker designs and the relationship of the moment of inertia.

Figure 111 shows the final valve seating shutdown rate of the inlet valve of illustrative SRFF-1L system.

Figure 112 is to show the table of torque spring Test Summary.

Figure 113 is the curve graph of the displacement and pressure during showing " pumping (pump-up) " test.

Figure 114 shows becoming in the durability of specified test period and gap for illustrative STFF-1L system Change.

Specific embodiment

Term used herein has its common meaning, unless redefining in the present specification, otherwise in this case New definition will replace common meaning.

VVA system embodiment-VVA system embodiment represents common generation VVA system conversion equipment, operating method, analysis With the unique combination of control system and improving technology.VVA system embodiment is in combination with one or more improving technologies.

I. discrete variable valve stroke (DVVL) system embodiment describes 1.DVVL system survey

It is described below and is grasped using the assembled hydraulic of double-fed type hydraulic lash adjuster (DFHLA) and oil control valve (OCV) The discrete variable valve stroke (DVVL) of the actuated by cams of work converts rocker arrangement, just looks like that it will be installed in II type valve machine It is the same on inlet valve in structure.In alternative embodiments, the device can be applied in piston driven internal combustion engine into Any combination of valve or exhaust valve.

As shown in Fig. 2, the exhaust valve mechanism in the present embodiment includes fixed rocker arm 810, single peach tip camshaft 811, mark Quasi- hydraulic lash adjuster (HLA) 812 and exhaust valve 813.As shown in Figures 2 and 3, the component of inlet valve mechanism includes that three peach tips are convex Wheel shaft 102, conversion rocker arm assembly 100, the double-fed type hydraulic lash tune with upper fluid port 506 and lower fluid port 512 Save device (DFHLA) 110 and electric-liquid type solenoid oil control valve component (OCV) 820.OCV 820 have input port 821 with And respectively the first control port 822 and the second control port 823.

Referring to Fig. 2, the shared specific common geometry of intake and exhaust valves mechanism, including valve 813 and HLA 812 Spacing and valve 112 and DFHLA 110 spacing.Common geometry is maintained to allow utilizing standard chain drive system While using the type cylinder head space II that is existing or slightly modifying encapsulate DVVL system.Inlet valve mechanism and exhaust door machine The shared additional member shown in Fig. 4 of both structures includes valve 112, valve spring 114 and cotter seat 116.Inlet valve and The also shared valve split collets of both exhaust valves and valve stem seal (not shown).It is several by maintaining to share using shared component What shape reduces the implementation cost of DVVL system to the maximum extent.

Inlet valve organ shown in Fig. 3 cooperates to open and have high-lift cam axis peach tip 104,106 or low The inlet valve 112 of lift cams axis peach tip 108.High-lift cam axis peach tip 104,106 is designed to provide and fixed air inlet The comparable performance of door machine structure, and the roughly circular portion by lift does not occur, may include the lift portion in linear transitions portion and correspond to The nose of maximum lift forms.Low lift cams axis peach tip 108 allows lower valve stroke and inlet valve to close in advance.It is low Lift cams axis peach tip 108 also includes the roughly circular portion that lift does not occur, the substantially straight line portion as lift transition and correspondence In the nose of maximum lift.Curve graph in Fig. 5 shows the diagram of the relationship of valve stroke 818 and crankangle 817.Cam Axis high lift profile 814 and fixed exhaust valve lift profile 815 are contrasted with low lift profile 816.Shown in profile 816 Low lift events reduce both lift and duration of induction event during part-throttle operates to reduce throttle loss And realize the raising of fuel economy.This is also referred to as inlet valve and closes in advance or EIVC.When needing full power operation, DVVL system System returns to high lift profile 814, this is similar to standard fixed lift event.High lift is transitioned into from low lift and from high lift mistake It crosses to low lift and occurs in a camshaft is turn-taked.Exhaust lift event shown in profile 815 be it is fixed and with low liter Journey or the identical mode of high lift induction event operate.

System for controlling DVVL conversion uses hydraulic operation.The hydraulic control used for the embodiment of teachings of the present application System and being illustrated schematically in Fig. 6 for operating system 800 show.Hydraulic control and operating system 800 are designed to patrol by control The order collected, which delivers hydraulic fluid to, provides the mechanical latch component of the conversion between high lift state and low lift condition.Hair When the control of motivation control unit 825 starts mechanical conversion process.Shown in hydraulic control and operating system 800 in four-in-line With in above-mentioned inlet valve mechanism in II h type engine h, but technical staff will be appreciated that, the system of controling and operating can be applied In the engine of other " types " and the cylinder with different number.

Previously mentioned and in DVVL system described herein several improving technologies can be other with described in the text The DVVL component of a system is used in conjunction with, to provide unique combination, will describe some combinations in text:

2. DVVL system improving technology

For several technologies in the system in different application, they to be described as DVVL disclosed herein in the text The component of system.These components include:

2.1. oil control valve (OCV) and oil control valve component

Now, referring to Fig. 7-9, OCV be guidance or do not guide pressurization hydraulic fluid so that rocker arm 100 in high lift mode The control device converted between low lift mode.OCV is enabled and deactivated to be caused by control device signal 866.It is one or more OCV can be encapsulated in individual module to form component.In one embodiment, OCV component 820 is packaged together by two Solenoid type OCV composition.In the present embodiment, control device provides signal 866 to OCV component 820, to make OCV to oil Control channel 802,803 provides high pressure (in embodiment, at least oil pressure of 2bar) or low pressure (in embodiment, 0.2- It is 0.4bar) oily, so that conversion rocker arm 100 is made to be in low lift mode or high lift mode, it is such as shown in figs. 8 and 9 respectively.With Comprising being further described to 820 embodiment of OCV component in lower chapters and sections.

2.2. double-fed type hydraulic lash adjuster (DFHLA):

In the presence of many for maintaining the hydraulic lash regulating device in the gap in engine.Carry out rocker arm 100 (Fig. 4) DVVL conversion needs conventional gap management, but tradition HLA device is not enough to provide the required oil stream amount requirement for conversion, The relevant side loaded applied by component 100 is born during operation, and is assemblied in limited encapsulated space.It describes and turns The compact double-fed type hydraulic lash adjuster 110 (DFHLA) that rocker arm 100 is used together is changed, is had features designed to low consumption One group of parameter of optimal oil stream dynamic pressure is provided and geometry and is designed to management one group of parameter of side loaded and several What shape.

As shown in Figure 10, the cooperation of bulb stopper end 601 is in the ball-and-socket 502 for allowing moving in rotation freedom degree in any direction In.This allows bulb stopper end 601 within a particular mode of operation --- for example low lift is being transformed into from high lift and from low lift When being transformed into high lift --- side and possibly asymmetric load.With the typical bulb stopper end for HLA device on the contrary, The 110 bulb stopper end 601 DFHLA is made of thicker material to prevent side loaded, is shown in Figure 11 as plug thickness 510.

The material selected for bulb stopper end 601 with higher can also allow motion stress load, such as chrome alum alloy.

Flow of pressurized path in DFHLA 110 be designed to high flow capacity and low pressure drop with ensure consistent hydraulic conversion and Reduced pumping loss.DFHLA is mounted on really to be sized to lean against within the engine and seal on outer surface 511 shown in Figure 11 In cylindrical reception seat.The cylindrical reception seat combines with the first oil flow passage 504 and forms the envelope with regulation sectional area Close fluid path.

As shown in figure 11, the preferred embodiment includes four oily flowing ports 506 (only showing two) because they with etc. It is arranged in away from the mode separated around the base portion of the first oil flow passage 504.In addition, two the second oil flow passages 508 with etc. It is arranged in around bulb stopper end 601 away from the mode separated, and is in fluid communication through oily port 506 and the first oil flow passage 504.Oil Flowing ports 506 and the first oil flow passage 504 are really sized to particular area and are spaced in around DFHLA 110 with true Protect the uniform oil stream amount and minimum pressure drop from first flow channel 504 to third oil flow passage 509.Third oil flow passage 509 determine size for the combination oil stream from multiple second oil flow passages 508.

2.3. class bores carbon coating (DLCC)

The friction that can be reduced between processed components will now be described and necessary abrasion and loading characteristic are provided simultaneously Class bore carbon coating (DLC).There are similar coating material and process, none be sufficient for for VVA system using when encounter Many requirements.For example, 1) have enough hardness, 2) have suitable bearing capacity, 3) in operating conditions in chemistry Stablize, 4) be suitable for temperature be no more than components annealing temperature technique, 5) meet service life of aeroengine requirement and 6) and Steel on steel interface, which are compared, provides reduced friction.

The unique DLC coating process for meeting above-mentioned requirements will now be described.Selected DLC coating is from hydrogenated amorphous Carbon or similar material.DLC coating is made of the several layers described in Figure 12.

1. first layer is the chromium adhesion layer 701 as the bonding agent between metal receiving surface 700 and next layer 702.

2. the second layer 702 is the nitridation for increasing the interface between base metal receiving surface 700 and DLC coating ductility Chromium.

3. third layer 703 is the combination of chromium carbide and the hydrogenated amorphous carbon that DLC coating is bound to chromium nitride layer 702.

4. the 4th layer 704 is made of the hydrogenated amorphous carbon for providing hard service wear interface.

The combination thickness of layer 701-704 is between 2 microns and 6 microns.DLC coating cannot be applied directly to metal receiving Surface 700.

In order to meet life requirement and in order to adhere to the first chromium adhesion layer 701 suitably with substrate receiving surface 700, Mechanically apply very specific surface smoothness to base receiving surface 700.

2.4 sensing and measurement

It can be used to verify translative mode using the information of sensor collection, determine error condition, or provide and be used in combination through analyzing In the information of conversion logic and timing.Several sensing devices that can be used are described below.

2.4.1 double-fed type hydraulic lash adjuster (DFHLA) is mobile

Variable valve-operating (VVA) technology is designed to convert rocker arm using conversion equipment such as DVVL or cylinder is closed down (CDA) rocker arm changes valve lift profile during engine operating.When using these devices, valve lift state is confirmation Successful conversion operation or detection error condition/failure important information.

DFHLA is not only used to manage gap, but also is used to supply the conversion rocker arm assembly for using such as CDA or DVVL etc VVA system in conversion hydraulic fluid.As shown in the cross-sectional view of Figure 10, for DVVL rocker arm assembly 100 it is usual between Gap adjust (being described in detail in following chapters and sections) make bulb stopper 601 is kept during both high lift operation and low lift operation and Inner arm 122 receives seated connection touching.Bulb stopper 601 is designed to on-demand when meeting the variation between high lift state and low lift condition It is mobile.The measurement carried out compared with known operating condition to the movement of Figure 13 514 can determine latched position state.At one In embodiment, noncontacting switch 513 is between HLA outer body and bulb stopper cylinder-shaped body.Second example can be added to permit Perhaps the hall effect sensor installed by way of the variation in the magnetic field that specific movement 514 generates is measured.

2.4.2 valve stem is mobile

Variable valve-operating (VVA) technology is designed to operate the phase in engine using conversion equipment such as DVVL conversion rocker arm Between change valve lift profile.Valve lift state is that the successful conversion operation of confirmation or detection error condition/failure are important Information.Valve stem position and relative movement sensor can be used for the function.

Monitoring VVA transition status simultaneously judges whether there is one embodiment of translation exception and shows in Figure 14 and 14A.Root According to the one side of this introduction, valve that it can be mechanically coupled to by the sensor of linear variable difference transformer (LVDT) type 872 linear motion is transformed to corresponding electric signal.LVDT linear position sensor be it is ready-made, they can measure as low as hundred Ten thousand/several inches to up to several inches of movement.

Figure 14 A shows the component for the typical LVDT being mounted in stem guide 871.LVDT internal structure is by a pair of of phase Main coiling 899 between the second level coiling 897,898 wound together forms.In embodiment, coiling 897,898,899 wound on It is formed in the recessed hollow portion in valve guide bushing main body 871, the recessed hollow portion is with thin-walled section 878, the first end wall 895 It is boundary with the second end wall 896.In the present embodiment, valve guide bushing main body 871 is static.

Now, 4,14A and 14B referring to Fig.1, the moving element of the LVDT device be referred to as core 873 by magnetic-permeable material The individual tubulose armature constituted.In embodiment, core 783 is assembled in using any suitable method and manufacture material such as iron In valve 782.

Core 873 is axially moved freely in the inside of main coiling 899 and second level coil 897,898, and it and just quilt The valve 872 of measurement position is mechanically coupled to.There is no physical contacts between core 873 inside hole and valve guide bushing 871.

In operation, the main coiling 899 of LVDT (is encouraged by applying the alternating current of appropriate amplitude and frequency based on known Magnetic) and be powered.The magnetic flux generated in this way is coupled by core 873 with adjacent second level coiling 897 and 898.

As shown in Figure 14 A, if core 873 is located at the midway between second level coiling 897,898, equal magnetic flux in It is to be coupled with each second level coiling.In 873 position (being known as zero point) of benchmark midway core, differential voltage output is substantially Zero.

Core 873 is arranged so that it extends past the both ends of coiling 899.As shown in Figure 14B, if core 873 is mobile Distance 870 is so that it is more closer than with coiling 898 with coiling 897, then more magnetic flux couples and less magnetic flux with coiling 897 It is coupled with coiling 898, so as to cause the differential voltage of non-zero.Measurement differential voltage can indicate the shifting of valve 872 by this method Dynamic both direction and position.

In the second embodiment shown in Figure 14 C and 14D, above-mentioned LVDT device is by removing the second coil in Figure 14 A 898 and be modified.When coil 898 is removed, the voltage that incudes in coil 897 is by the end position relative to core 873 Set 874 variations.In the embodiment known to the moving direction and time point of valve 872, it is only necessary to which a secondary coil 897 is moved to measure Dynamic amplitude.As described above, if 873 part of core of valve can use drying method positioning and manufacture.For example, end position 874 welding can be used to position end in conjunction with Ni-based non-core material and iron-based core material, the Physical scaling down of diameter Position 874 can be inserted with the magnetic flux or fritter iron-based material that change specific position and be located in end position 874.

It will be appreciated that, the LVDT sensor component in an example can be located at valve guide bushing 871 according to the present invention Near top is to allow the heat dissipation lower than the point.Although this position can be higher than the typical pad for valve stem manufacture, But welding position can move as described above.Core 873 relative to second level coiling 897 position and inducted great voltage at Ratio.

It uses LVDT sensor as described above to have the advantages that in the engine of operating several, including 1) is transported without friction Turn --- in, Mechanical Contact is not present between the core 873 and coil block of LVDT.Machine is also extended without friction The tool service life.2) virtually limitless resolution ratio --- since LVDT is operated in no friction structure based on electromagnetic coupling principle, so It can measure the little change of core position, only be limited by the resolution ratio of noise and Output Display Unit in LVDT signal-conditioning unit System.The characteristic also causes outstanding reproducibility, and 3) environment robustness --- material and the construction technology for assembling LVDT cause Firm, durable sensor steady to various environmental conditions.The combination of coiling 897,898,899 can be sealed then with epoxy resin In valve guide bushing main body 871, so as to cause excellent waterproof and dampproof performance, and big shock loading and high vibration are absorbed Horizontal ability.In addition, coil block can be by closed to resist oil and corrosive environment.4) zero point reproducibility --- it is above-mentioned The position of the zero point of LVDT is even also highly stable and repeatable in its very wide operating temperature range.5) quickly dynamic is rung Answer --- there is no frictions, and LVDT to be allowed quickly to respond the variation of core position during common operating.LVDT sensing The dynamic response of device is only limited by the small effect of inertia due to caused by core assembly quality.In most cases, LVDT feels The response of examining system is determined by the characteristic of signal-conditioning unit.6) absolutely output --- LVDT is opposite with increment output device exhausted To output device.It means that the position data sent from LVDT is not damaged in the case where power loss.When measurement is When system is restarted, the output valve of LVDT will with it before power failure occurs it is identical.

Above-mentioned valve stem position sensor determines the position of the valve stem during engine operating using LVDT type sensor It sets.The sensor can be any of sensor technology, including hall effect sensor, can track the position of valve stem And by monitoring position feedback to the electronics of ECU, optically and mechanically sensor.

2.4.3 components position/movement

Variable valve-operating (VVA) technology is designed to operate the phase in engine using conversion equipment such as DVVL conversion rocker arm Between change valve lift profile.The variation of transition status can also change in component relative to each other utterly or in VVA component Component position.Change in location measurement can be designed and be embodied as the state of monitoring VVA conversion, and possibly determine whether There are translation exceptions.

Now, with reference to Figure 15-16, exemplary DVVL conversion rocker arm assembly 100 can be configured to have measurement relative movement, The accurate noncontacting proximity sensor 828 of movement or distance.

In one embodiment, movable sensor 828 is located near first end 101 (Figure 15), to be directed to high lift mode Movement with low lift mode assessment outer arm 120 relative to known location.In this example, movable sensor 828 include wound on Line around the core of permanent magnetization, and position and be oriented and generated with ferrous material by its known magnetic field by measuring The variation of magnetic flux detect movement.For example, the outer arm brace 875 when magnetic (ferrous material) passes through position sensor 828 Permanent magnetic field when, flux density be adjusted to incude in coil alternating voltage and generate with the degree of approach of pull rod 875 at than The electric power output of example.Modulation voltage inputs control unit of engine (ECU) (describing in following chapters and sections), and wherein processor is adopted Start 100 conversion operation of rocker arm assembly with logic and calculating.In embodiment, voltage output can be binary, it is meant that Voltage signal with or without instruction high lift or low lift.

Visible location sensor 828 may be positioned to the movement of other components in measurement rocker arm assembly 100.It is real second It applies in example, sensor 828 can be located at the second end 103 of DVVL rocker arm assembly 100 (Figure 15) to assess inner arm 122 relative to outer arm 120 position.

Sensor 828 can be positioned to directly assess lock bolt 200 in DVVL rocker arm assembly 100 by 3rd embodiment It sets.Lock bolt 200 and sensor 828 are engaged with each other and fix when they are in the lock state (high lift mode), and are directed to Unlock (low lift) operation is moved apart.

Inductosyn detection movement can also be used.Sensor 877 can be to allow to measure such as valve stem 112 and be The hall effect sensor that the mode of no movement is installed.

2.4.4 pressure characteristic

Variable valve-operating (VVA) technology is designed to operate the phase in engine using conversion equipment such as DVVL conversion rocker arm Between change valve lift profile.Since lock state is that ECU can be made to be able to carry out various functions such as to adjust fuel/air mixture Increasing mileage travelled, reducing pollution or adjusting the important input to ECU of idling and pinking, successfully turn so needing to confirm It changes operation or detects measuring device or the system of error condition or failure to carry out control appropriate.In some cases, it is desirable to Transition status report and error notification are to meet regulation.

In the embodiment for including hydraulically operated DVVL system 800 as shown in FIG. 6, the variation of transition status is provided Visibly different hydraulic conversion Fluid pressure instruction.The necessary hydraulic rigid of starting conversion is generated due to needing Fluid pressure Degree, and since hydraulic fluid passage is geometrically defined special modality and chamber, so generating can be used to predictably Determine the Characteristic pressures instruction of the state that locks or unlocks or translation exception.Measurement pressure can be described and by measurement result and Know several embodiments being compared with acceptable operating parameters.Pressure measurements can be followed by checking in several conversions The Fluid pressure of ring and analyzed from macroscopic aspect, or assessed for persistently several milliseconds of single change event.

Referring now to Fig. 6,7 and 17, graphical representation of exemplary (Figure 17) is shown when conversion rocker arm 100 is under high lift or low lift The valve lift height about the time of cylinder 1 changes 882 when operating and converting between high lift and low lift.Hydraulic conversion The corresponding data of system shows (Figure 17) on scale at the same time, the upper channel measured including the use of pressure sensor 890 802, the oil pressure 880 in 803 and the electric current 881 for the solenoid valve 822,823 being opened and closed in OCV component 820.As can be seen, this Kind shows OCV switching current 881, control 880 and of pressure during all modes of operation from the analysis rank of macroscopic aspect Association between lift 882.For example, at the moment 0.1, OCV is command by conversion, as shown in the electric current 881 increased.When OCV is converted When, the control pressure 880 of increase causes high lift to low lift change event.With to one or more complete conversion cycles Evaluation operation, it can be estimated that the appropriate behaviour including OCV He the subsystem for the pressurized fluid transportation system for leading to rocker arm assembly 100 Make.The valve stem movement for example as described above of other independent measurement results can be used to enhance translation exception judgement.Such as may be used See, the OCV of inlet valve and/or exhaust valve that these analyses can be used to control one or more cylinders for any quantity is held Row.

Using similar method, but using measuring and analyzing data with millisecond rank during change event, foot is provided Enough detailed control pressure informations (Figure 17 A, 17B), with only in the case where not measuring valve stroke or mobile latch pin directly On the spot assess successful change event or translation exception.In the embodiment using this method, pass through the pressure transient that will be measured It is compared to judge to turn with developing dduring test and being stored in the known mode of operation pressure transient in ECU for analysis Change state.Figure 17 A and 17B are shown for generating the example for converting the known operation pressure transient of rocker arm in DVVL system Property test data.

The pilot system includes four conversion rocker arm assemblies 100, OCV component 820 (Fig. 3), two tops as shown in Figure 3 Oily control channel 802,803 (Fig. 6-7) and for controlling hydraulic operation fluid temperature (F.T.) and pressure in control channel 802,803 The closed-loop system of power.Each control channel provides the hydraulic fluid under the pressure after adjusting, to control two rocker arm assemblies 100.Figure 17 A shows effective single trial operation, it is shown that OCV solenoid valves are to start from high lift state to low lift shape The data when conversion of state.Installing instruments, lock bolt is mobile 1003, the pressure 880 in control channel 802,803, OCV electricity to measure Stream 881, the pressure 1001 (Fig. 6-7) in hydraulic fluid supply source 804 and lock bolt gap and cam clearance.It can be suitable by event Sequence is described as follows:

0ms-ECU turn-on current 881 is so that OCV solenoid valves

10ms- leads to the solenoidal switching current 881 of OCV and is enough to be adjusted to pressure to compare as shown in pressure curve 880 It is high in control channel 802,803.

10-13ms- supply pressure when hydraulic fluid is from supply source 804 (Fig. 6-7) inflow in control channel 802,803 Force curve 1001 is reduced under the pressure adjusted by OCV.In response, pressure 880 is quick in control channel 802,803 Rise.Latch pin is mobile such as the beginning as shown in latch pin moving curve 1003.

13-15ms- supply pressure curve 1001 returns to stable non-adjustment state in stability of flow.Control channel 802, the pressure 880 in 803 rises to the higher pressure adjusted by OCV.

880 rise/fall transition of pressure in 15-20ms- control channel 802,803 is in pressurized hydraulic fluid by lock bolt (latch pin moving curve 1002) is generated when pushing back in place completely, and hydraulic flow and pressure are stablized in the unadjusted pressure of OCV Power.Pressure spike 1003 is the feature of the transition.

In 12ms and 17ms, can see in pressure curve 880 consistent with the suddenly change of latched position 1002 Visibly different pressure transient.

Figure 17 B shows effective single trial operation, it is shown that OCV solenoid valve is powered off to start from low lift condition to promotion The data when conversion of journey state.Event sequence can be described as follows:

0ms-ECU cuts off electric current 881 and converts so that OCV solenoid valve powers off.

5ms-OCV solenoid it is mobile enough to mostly with will after adjusting, that the hydraulic fluid of lower pressure imports control is logical Road 802 and 803 (pressure curve 880).

Pressure in 5-7ms- control channel 802,803 rapid decrease as shown in curve 880 when OCV turns down pressure.

7-12ms- and low pressure point 1005 are consistent, and such as lock bolt of the lower pressure starting in control channel 802,803 is mobile bent Lock bolt shown in line 1002 is mobile.880 transition of pressure curve is engaged in lock pin spring 230 (Figure 19) compression and movement with lock bolt Start when hydraulic fluid in space.

The latch pin shown in latch pin moving curve 1002 of pressure transient shown in 12-15ms- pressure curve 880 is moved It is imported again when dynamic completion.

Pressure in 15-30ms- control channel 802,803 stablizes the pressure after OCV adjusting as shown in pressure curve 880 Power.

As described above, can see in pressure curve 880 and latched position 1002 in 7-10ms and 13-20ms The consistent visibly different pressure transient of suddenly change.

As it was noted above, and in following sections, fixation geometric configuration, hole, gap and the chamber of hydraulic channel and The rigidity of lock pin spring is that have with the hydraulic response of the variation for the hydraulic fluid pressure after adjusting and mechanical switching rate The variable of pass.Pressure curve 880 in Figure 17 A and 17B describes the DVVL conversion rocker arm system operated within the acceptable range System.During operation, specific pressure rate of rise or rate of descent (slope of curve) are by table at the time of event listed above The feature of sign suitably operated.The example of error condition includes: to show the time of the pressure events of deterioration of lock bolt response time Passage, the whole of the amplitude of the variation (pressure curve slope variation) or pressure events of events incidence reduce.For example, 15- Rising in the 20ms period lower than expected pressure indicates that lock bolt is not yet fully retracted, to potentially cause critical transitions.

With the test data in the oil pressure of 50psi and 70 degrees Celsius of fuel temperature measurement these examples.A series of different operations Test under state can provide the database that be used to convert the indicatrix of diagnosis by ECU.

Description diagnoses another embodiment of transition status using pressure measurements.DFHLA 110 as shown in Figure 3 was both For managing gap, and for supplying the VVA system for operating the conversion rocker arm assembly using such as CDA or DVVL etc Hydraulic fluid.As shown in the cross-sectional view of Figure 52, the usual gap adjustment for DVVL rocker arm assembly 100 causes bulb stopper 601 to exist It keeps touching with the receiving seated connection of interior arm component 622 during both high lift operation and low lift operation.When assembling within the engine When good, DFHLA 110 is in a fixed position, and inner rocker arm component 622 carries out moving in rotation around top dome termination contact 611.Inner arm Change when the conversion between high lift state and low lift condition of the moving in rotation of component 622 and the size of bulb stopper load 615. Bulb stopper 601 is designed to mobile in a manner of compensating in load and mobile variation.

Balancing force for bulb stopper load 615 is when lower control channel 805 is connected to lower end 512 with chamber 905 under Hydraulic fluid pressure in control channel 805 provides (Figure 11).As shown in fig. 6-7, hydraulic under unregulated pressure Fluid is sent in lower control channel 805 from engine cylinder cap.

In embodiment, pressure sensor is placed in the hydraulic channel 805 of the gap-regulating portion of feeding DFHLA 110 In.Pressure sensor can be used to be transitioned into low lift condition from high lift state or be transitioned into high lift from low lift condition Instantaneous pressure variation when state in the hydraulic channel 805 of monitoring feeding clearance adjuster.By being transformed into from one mode Pressure instruction is monitored when another mode, which is able to detect when variable valve-operating system occurs in any one position Failure.In embodiment shown in the relationship of time as unit of as pressure with by millisecond, pressure indicative curve provides can be with Character shape including amplitude, slope and/or other parameters.

For example, Figure 17 C shows the diagram of inlet valve lift profile curve 814,816 with the relationship as unit of millisecond, The illustrating superposition of the diagram and the relationship of hydraulic channel pressure curve 1005,1005 and identical time ruler.Pressure curve 1006 and valve lift profile curve 816 correspond to low lift condition, and pressure curve 1005 and valve lift profile 814 are corresponding In high lift state.

During quiet rum, pressure indicative curve 1005,1006 present period sex expression, wherein DFHLA compensation with Cam push down on the alternate bulb stopper load that rocker arm assembly is distributed with compression valve spring (Fig. 3) and when providing valve stroke 615, visibly different point is generated when valve spring elongation is to close valve and when cam is located on the basic circle that lift does not occur Peak 1007,1008.As shown in Figure 17 C, instantaneous pressure spike 1006,1007 respectively with low lift profile 816 and high lift profile 814 spike is corresponding.When hydraulic system pressure is stablized, steady state pressure indicative curve 1005,1006 restores.

As it was noted above, and in following sections, fixation geometric configuration, hole, gap and the chamber of DFHLA hydraulic channel It is and variable related for the given hydraulic response and pressure transient of hydraulic fluid pressure and temperature.Pressure in Figure 17 C Indicative curve 1005,1006 describes the DVVL conversion rocker arm system operated within the acceptable range.During operation, specific Pressure rate of rise or rate of descent (slope of curve), pressure peak and surge pressure about maximum lift at the time of be also possible to lead to The feature suitably operated characterized at the time of crossing change event.The example of error condition may include pressure events time passage, The amplitude of the variation (pressure curve slope variation) of the incidence of event, unexpected inexpectancy pressure transient or pressure events it is whole Body decline.

A series of test under different operating states can provide the data that be used to convert the indicatrix of diagnosis by ECU Library.One or several pressure values can be used based on system configuration and vehicle needs.It can be by the pressure curve and standard of monitoring Curve is compared to determine when system breaks down.

3. conversion and control and logic

3.1. engine embodiment

Existed with controlled pressure to the DVVL hydraulic fluid system that DVVL shown in Fig. 4 conversion rocker arm 100 conveys engine oil It is described in following chapters and sections, because it may be mounted on the inlet valve in the II type valve mechanism in four cylinder engine.It is replacing For in embodiment, which can be applied to inlet valve or exhaust valve in piston driven internal combustion engine Any combination.

3.2. lead to the hydraulic fluid transportation system of rocker arm assembly

With reference to Fig. 3,6 and 7, hydraulic fluid system conveys engine oil to DVVL conversion rocker arm 100 (Fig. 4) with controlled pressure 801.In the arragement construction, the pressure controlled engine oil that do not carry out from cylinder head 801 is fed into HLA lower feeding channel In 805.As shown in figure 3, the oil is in fluid communication with the lower feeding entrance 512 of DFHLA always, it is used to execute usually in this DFHLA Hydraulic lash adjust.The pressure controlled engine oil that do not carry out from cylinder head 801 is also fed into oil control valve component and enters Mouth 821.As described above, the OCV component 820 for the DVVL embodiment includes adjust the oil pressure from common inlet 821 two A solenoid valve being operating independently.Hydraulic fluid from 820 first control port of OCV component outlet 822 is supplied on first Channel 802, and the hydraulic fluid from the second control port 823 is supplied to the second upper channel 803.First OCV determines 1 He of cylinder The lift mode of cylinder 2, and the 2nd OCV determines the lift mode of cylinder 3 and cylinder 4.As shown in figure 18 and in following chapters and sections Described in, the operation of the valve in OCV component 820 is by control unit of engine 825 using based on to specific physical configuration sensing With the specific quantity of the information of storage, conversion window and one group of operating condition such as cylinder and the logic guidance of specific oil temperature. Hydraulic fluid after pressure regulation from upper channel 802,803 is directed into DFHLA upper port 506, it is transmitted through channel 509 herein To conversion rocker arm assembly 100.As shown in figure 19, hydraulic fluid is via the first oily channel 144 and the second oily channel 146 through rocking arm set Part 100 is transmitted to stop pin assembly 201, it is used to start the conversion between high lift state and low lift condition herein.

When the cleaning air accumulated in upper channel 802,803 is to maintaining hydraulic stiffness and reducing pressure to the maximum extent to rise Between variation for it is critically important.Pressure rise time directly affect conversion operation during lock bolt traveling time.Quilt shown in fig. 6 Dynamic bleeder port 832,833 is increased to the high point in upper channel 802,803 being released to the air accumulated positioned at valve cap In the cylinder head gap of lower section.

3.2.1 it is conveyed for the hydraulic fluid of low lift mode:

Referring now to Figure 8, DVVL system is designed under low lift mode from idle running to 3500rpm.Rocking arm set The cross-sectional view of the peach tip of part 100 and 3 cam 102 shows low lift operation.The main member of component shown in Fig. 8 and 19 includes interior Arm 122, roller bearing 128, outer arm 120, slide block pad 130,132, lock bolt 200, lock pin spring 230, pivot 118 and lost motion torsion Spring 134,136.For low lift operation, when the solenoid valves in OCV component 820, pressure >=2.0bar is not adjusted Oil through 802,803 and DFHLA of control channel 110 be supplied to conversion rocker arm assembly 100.The pressure retracts lock bolt 200, from And inner arm 122 and outer arm 120 are unlocked, and them is allowed to independently move.High-lift cam axis peach tip 104,106 (Fig. 3) is protected It holds and is contacted with the sliding section pad 130,132 on outer arm 120.120 around the pivot 118 of outer arm is rotated and is not distributed to valve 112 Any movement.This is commonly referred to as " lost motion ".It is closed in advance since low lift cam profile 816 (Fig. 5) is designed to valve, So conversion rocker arm 100 must be designed to absorb the total movement for coming from high-lift cam axis peach tip 104,106 (Fig. 4).Come Ensure that outer arm 120 keeps contacting with high lift peach tip 104,106 (Fig. 3) from the power of lost motion torque spring 134,136 (Figure 15).It is low Lift peach tip 108 (Fig. 3) is contacted with the roller bearing 128 on inner arm 122 and valve is closed in advance in each low lift valve operating Profile 816 (Fig. 4) is opened.

3.2.2 it is conveyed for the hydraulic fluid of high lift mode

Referring now to Figure 9, DVVL system is designed under high lift mode from idle running to 7300rpm.Conversion is shaken The cross-sectional view of the peach tip of arm 100 and 3 cam 102 shows high lift operation.The main member of component shown in Fig. 9 and 19 includes interior Arm 122, roller bearing 128, outer arm 120, slide block pad 130,132, lock bolt 200, lock pin spring 230, pivot 118 and lost motion torsion Spring 134,136.

Solenoid valve in OCV component 820 is powered down to realize high lift operation.Lock pin spring 230 stretches out lock bolt 200, To lock inner arm 122 and outer arm 120.The function of the arm of locking is similar to fixed rocker arm.Symmetrical high lift peach tip 104, 106 (Fig. 3) are contacted with the slide block pad 130 (being not shown 132) on outer arm 120, to make inner arm 122 around the 110 ball end 601 DFHLA It rotates and opens valve 112 (Fig. 4) in each high lift profile 814 (Fig. 4).During this period, pressure from 0.2bar adjust to The oil of 0.4bar is supplied to conversion rocker arm 100 through control channel 802,803.The oil pressure for maintaining 0.2 to 0.4bar keeps oil circuit It is full of but retracts lock bolt 200.

Under high lift mode, the double-fed function of DFHLA under maximum engine rotation speed for ensuring the suitable of valve mechanism When backlash compensation is critically important.Cylinder head oil pressure is transmitted to DFHLA lower port 512 (Figure 11) by the lower channel 805 in Fig. 9.DFHLA Lower part be designed to as usual hydraulic lash compensation mechanism work.DFHLA110 mechanism is designed to ensure that hydraulic device has There is sufficient pressure to avoid being aerated and all remaining full of oil under all engine speed.Hydraulic stiffness are maintained using the system With valve mechanism function appropriate.

Table in Figure 20 summarizes the pressure state under high lift mode and low lift mode.It is logical to also show DFHLA The hydraulic pressure separating of normal clearance compensation function and rocker arm assembly conversion function.Engine is high lift mode (lock bolt is stretched out and engaged) Lower starting, because this is default mode.

3.3 operating parameters

One key factor of operation DVVL system is the reliable control from high lift mode to low lift mode.DVVL gas Door operation system only can just be converted during scheduled time window between each mode.As described above, from high lift mode to low Lift mode and conversion from low lift mode to high lift mode pass through the signal for coming from control unit of engine (ECU) 825 Starting, the ECU using analysis storage information for example for the conversion window of specific physical configuration, the operating condition of storage and Pass through the logic of sensor collection treated data.The conversion window duration is determined by DVVL system physical configuration, is wrapped Include number of cylinders, by the quantity of the single OCV cylinder controlled, valve lift duration, engine speed and hydraulic control With the lock bolt response time intrinsic in mechanical system.

3.3.1 the data collected

Real time sensor information includes the input from any amount of sensor, such as exemplary DVVL shown in Fig. 6 Shown in system 800.Sensor can include: 1) surveyed in one embodiment using above-mentioned linear variable difference transformer (LVDT) Fixed valve stem mobile 829,2) utilize hall effect sensor or the movement/position 828 and lock bolt position of motion detector measurement Set 827,3) utilize the DFHLA movement 826,4 close to switch, hall effect sensor or the measurement of other sensors) oil pressure 830, With 5) oil temperature 890.Camshaft rotation position and speed can be collected directly or be estimated from engine speed sensor.

In in the VVA system of hydraulic operation, oil temperature influences the conversion in the system for such as CDA and VVL etc The rigidity of hydraulic system.If oil supercooling, viscosity slows down change event, so as to cause failure.The relationship is in Figure 21-22 It is shown for exemplary DVVL conversion rocker arm system.Utilize the Fig. 6 being located near point of use rather than in engine oil crankcase Shown in the accurate oil temperature that obtains of sensor 890 most accurate information is provided.In one example, close to oil control valve (OCV) Oil temperature in the VVA system of monitoring has to be larger than or is equal to 20 DEG C, to start low lift (unlock) with desired hydraulic stiffness Operating.The commercially available component of any quantity such as thermocouple be can use to measure.Oil control valve was on April 15th, 2010 In US2010/0018482 disclosed in the disclosed U.S. Patent application US2010/0089347 announced and on January 28th, 2010 Detailed description, two applications are incorporated to by being cited in full text herein.

Sensor information is sent to control unit of engine (ECU) 825 as real-time motion parameter (Figure 18).

3.3.2 the information of storage

3.3.2.1 conversion window algorithm

Mechanical switch window:

The shape of each peach tip of three peach tips cam shown in Fig. 4 includes that basic circle portion 605,607,609, use of lift do not occur Come the lift portion for absorbing the transition part of mechanical clearance before lift events and keeping valve 112 mobile.For being mounted on system 800 In (Fig. 6) exemplary DVVL conversion rocker arm 100 for, when prevent its move lock bolt on it is zero load when high lift mode with it is low Conversion between lift mode can only occur during basic circle operates.To further describing in following chapters and sections for the mechanism It provides.Basic circle portion is illustrated in Fig. 5 with curve without lift portion 863.DVVL system 800 under 20 DEG C or more of oil temperature with Up to 3500 engine rpm turn-take interior conversion in a camshaft.Conversion except time window or predetermined oil condition may draw Critical transitions event is played, which be somebody's turn to do when the load on valve actuator switching member or engine valve is higher than Structure is designed to the transformation of a time point of the engine valve position in cycle of engine when the load adapted in conversion. Critical transitions event can cause the damage of valve mechanism and/or other engine components.Conversion window can be defined further To change the pressure in control channel and so that latch is moved to retracted position from extended position and be moved to stretching from retracted position The duration of camshaft crankangle needed for position.

As described above and shown in Fig. 7, DVVL system has the single OCV component of the solenoid valve independently controlled comprising two 820.First valve controls 802 pressure of the first upper channel and determines the lift mode of cylinder 1 and cylinder 2.In second valve control second 803 pressure of channel and the lift mode for determining cylinder 3 and 4.Figure 23 is the in-line four cylinder of (2-1-3-4) for cylinder spark order Engine shows the relationship of inlet valve timing (lift sequence) and crank shaft angle of OCV component 820 (Fig. 3) configuration.Cylinder two 851, the high lift inlet valve profile of cylinder 1, cylinder 3 853 and cylinder 4 854 is used as at the top of figure relative to crank Lift shown in angle is shown.The valve lift duration of corresponding cylinder lower part as lift duration region 855, 856, it 857 and 858 is shown relative to crankangle.Also show each cylinder without lift basic circle operating area 863.It must determine So that lock bolt is turn-taked the scheduled conversion window of interior movement in a camshaft, is configured to control simultaneously wherein arranging each OCV Two cylinders.

Mechanical switch window can be optimized by understanding and improving lock bolt movement.Referring now to Figure 24-25, rocker arm is converted The machine configurations of component 100 provide two kinds of completely different conditions for allowing to expand effective conversion window.Referred to as high lift is locked Fasten with a bolt or latch the first condition of limitation lock bolt 200 by order to open valve 112 and the load lock that applies in place when in high lift mould Occur under formula.The second condition of referred to as low lift lock bolt limitation prevents lock bolt 200 from stretching out in the lower section of outer arm 120 in outer arm 120 When occur under the low lift mode of unlock.These conditions are described as follows:

The limitation of high lift lock bolt:

Figure 24 shows the high lift event that lock bolt 200 is engaged with outer arm 120.It is supplied as valve overcomes by valve spring 114 The power given is opened, which is transmitted to outer arm 120 from inner arm 122 by lock bolt 200.When the power of spring 114 is transmitted by lock bolt 200 When, lock bolt 200 becomes to be locked in its extended position.In this case, by attempting to be transformed into low lift from high lift mode The hydraulic pressure converting OCV while mode and applying is not enough to overcome the power for locking lock bolt 20, to prevent it from retracting.The shape State makes the operation of the unloading of lock bolt 200 by allowing to apply before high lift event pressure and starting basic circle portion 863 (Figure 23) Expand total conversion window.When the power release on lock bolt 200, change event can be immediately begun to.

Low lift lock bolt limitation:

Figure 25 shows the low lift operation that lock bolt 200 is retracted under low lift mode.In the lift part of the event, outer arm 120 stop lock bolt 200, to prevent it from stretching out, even if OCV is converted, and hydraulic fluid pressure is reduced to return to high lift lock Determine state.The state is expanded by allowing to discharge hydraulic pressure before high lift event and reaching basic circle portion 863 (Figure 23) Total conversion window.Once reaching basic circle, lock pin spring 230 can be so that lock bolt 200 stretches out.By allowing to release before basic circle Power is bled off pressure to expand total conversion window.When camshaft is rotated to basic circle, can immediately begin to convert.

Figure 26 shows identical information shown in Figure 23, but also attached the mistake between high lift state and low lift condition Time needed for completing each step of mechanical switch process during crossing.These steps represent solid in the design of conversion rocker arm assembly The element of some mechanical switch.As described in Figure 23, the firing order of engine top together with inlet valve profile 851,852, 853, it 854 is shown, it is corresponding with the crank angle degrees on the basis of cylinder two.Lock bolt 200 is located at base in admission cam peach tip It must be moved when circle 863 (referring to mechanical switch window).Due to two cylinders of each solenoid valve control in OCV component 820, so The necessary timing of conversion window is at two cylinders of adaptation when being located on their own basic circle.Cylinder two is returned in 285 crank angle degrees Return basic circle.Lock bolt movement must complete 690 crank angle degrees before next lift events of cylinder two.Similarly, cylinder one It must be converted in 465 degree of return basic circles and with 150 degree of completions.As can be seen, the conversion window of cylinder one and cylinder two is not slightly Together.As can be seen, the first OCV electricity trigger starts to convert before one inlet valve lift events of cylinder, and the 2nd OCV electricity triggers Device starts to convert before four inlet valve lift events of cylinder.

Execute the change event that worst case analysis is given a definition with the maximum conversion speed in 3500rpm in Figure 26.Note that Engine can operate under the much higher revolving speed of 7300rpm；However, mode conversion does not allow to be higher than 3500rpm.Cylinder two Total conversion window is 26 milliseconds, and is broken down into two parts: 7 milliseconds of high lifts/low lift lock bolt limitation time 861 and 19 millisecond The mechanical switch time 864.10 milliseconds of mechanical response times 862 are all consistent for all cylinders.15 milliseconds of lock bolt limits Time 861 processed is longer for cylinder one, because OCV conversion starts while inlet valve lift events occur for cylinder one, And lock bolt is moved by limitation.

It must adapt to several mechanically and hydraulically limit to meet total conversion window.First of all, it is necessary to avoid in next air inlet Critical transitions 860 caused by the conversion unfinished before starting of door lift events.Secondly, experimental data shows at 20 DEG C most The maximum conversion time of mobile lock bolt is 10 milliseconds under low permission engine oil temperature.As pointed out in Figure 26, have 19 milliseconds can Mechanical switch 864 on basic circle.Since all test datas all show that switch machine response 862 will occur in first 10 In millisecond, so not needing all 19 milliseconds of mechanical switch time 864.The combination mechanically and hydraulically limited defines 17 milliseconds Worst case conversion time comprising lock bolt limit the time 861 lock door bolt mechanical response time 862.

DVVL conversion rocker arm system is designed to complete to convert with certain surplus, and wherein surplus is 9 milliseconds.In addition, 9 millis Second surplus allows to carry out mode conversion with the revolving speed higher than 3500rpm.Cylinder three and cylinder four correspond to it is as shown in figure 26 With the same conversion time of the different cylinders one for determining phase and cylinder two-phase.Do not consider to start the electricity in OCV component in this analysis Electric conversion time needed for magnet valve, but ECU can be easy to carry out calibration to consider the variable, because being energized to control from OCV It is predictable that channel oil pressure processed starts the time changed holding.

Now, referring to Fig. 4 and 25A, if the timing of camshaft rotation and the mobile only portion with wherein lock bolt 200 of lock bolt 200 Be bonded on the lock bolt 200 on an edge on outer arm 120 load with dividing is consistent, then critical transitions may occur.Once high Lift events start, and lock bolt 200 can be slided and be separated with outer arm 120.At this point, accelerated by the power of valve spring 114 Inner arm 122 leads to the impact between roller bearing 128 and low lift cams peach tip 108.Critical transitions are non-desired, because it Form the instantaneous out of control of rocker arm assembly 100 and valve movement, and the impact to system.DVVL conversion rocker arm is designed to meet The service life that critical transitions occur requires (lifetime worth).

3.3.2.2 the operating parameters of storage

Operating parameters include being used for as ECU825 (Figure 18) based on during the extension test as described in subsequent chapters and sections The data of collection carry out the storage information of conversion logic control.Several examples of known operating parameters can be described: in embodiment, 1) it should need 20 degrees Celsius of minimum oil temperature to be transformed into low lift condition from high lift state, 2) be deposited in engine sump tank In the minimum oil pressure greater than 2bar for conversion operation, 3) the lock bolt response time according to fig. 2 data shown in 1-22 and with Oil temperature variation, 4) it is as shown in figure 17 and described previously, predictable pressure change caused by hydraulic conversion operates such as is passed by pressure Occur in upper channel 802,803 (Fig. 6) determined by sensor 890,5) it is as shown in Figure 5 and described previously, it may be predetermined that And store the known valve movement based on lift profile 814,816 and the relationship of crankangle (time).

3.3 control logic

As described above, DVVL conversion can only occur during small predetermined time window under specific operating condition, and It may cause critical transitions event in the external conversion DVVL system of the time window, can cause to valve mechanism and/or other hairs The damage of motivation components.Since the engine condition of such as oil pressure, temperature, discharge and load etc can quickly change, so High speed processor can be used to analyze real-time status, they are compared with the known operating parameters of characterization operating system, Show result one to determine when to convert, and sends conversion signal.These operations per second can execute several hundred times or thousands of times.? In embodiment, which can be by application specific processor or by the existing multi-functional of referred to as control unit of engine (ECU) Automotive control system executes.Typical ECU has input unit including microprocessor for analog- and digital- data, may be programmed The processing unit and output section of memory and random access memory, the output section may include relay, switch and warning lamp behaviour Make.

In one embodiment, control unit of engine (ECU) 825 shown in Fig. 6 and 18 receives to come from multiple sensors Input, such as valve stem is mobile 829, movement/position 828, latched position 827, DFHLA are mobile 826, oil pressure 830 and oil temperature 890.The data (Figure 20) and changing window of permission operation temperature and pressure etc such as giving engine speed Mouthful (Figure 26 and describe in other chapters and sections) storage is in memory.Then the information of real-time collecting and storage information are compared Relatively and analyzed to provide the ECU logic of 825 conversion time and control.

After analyzing input, control signal is output to OCV 820 by ECU 825 to start conversion operation, is somebody's turn to do Conversion operation can timing at avoiding meeting the engine performance mesh of fuel economy and reduced discharge etc such as improved Target avoids critical change event simultaneously.If it is necessary, ECU 825 can also provide error condition to operator.

4.DVVL converts rocker arm assembly

The description of 4.1 components

It discloses a kind of for engaging the conversion rocker arm by pressurized fluid hydraulic operation of cam.Outer arm and inner arm are configured to Movement is transferred to the valve of internal combustion engine.Locking mechanism includes lock bolt, sleeve and directional component.Sleeve engages lock bolt and interior Hole in arm, and the opening for being used for directional component is also provided, the directional component is for providing lock bolt relative to sleeve and interior Arm is properly oriented within.Sleeve, lock bolt and inner arm have the reference marker for the optimal orientation for being used to determine lock bolt.

Exemplary transformation rocker arm 100 may be configured to have three peach tip cams as is shown in the perspective view of figure 4 during operation 102.Alternatively, similar rocker arm embodiment may be configured to utilize the design of other cams such as double peach tip cam works.Convert rocker arm 100 are configured with the mechanism for maintaining hydraulic gap adjustment and the mechanism for feeding hydraulic conversion fluid to inner arm 122. In embodiment, double-fed hydraulic lash adjuster (DFHLA) 110 executes two kinds of functions.Valve 112, spring 114 and spring base 116 are also configured with the component.Cam 102 has the first high lift peach tip 104 and the second high lift peach tip 106 and low liter Journey peach tip 108.Converting rocker arm has outer arm 120 and inner arm 122, as shown in figure 27.During operation, high lift peach tip 104, 106 contact with outer arm 120, and low lift peach tip is contacted with inner arm 122.Peach tip cause outer arm 120 and inner arm 122 periodically to Lower movement.This, which is moved downward, is transferred to valve 112 by inner arm 122, thus opens the valve.Rocker arm 100 can be in high lift mode It is converted between low lift mode.Under high lift mode, outer arm 120 is locked on inner arm 122.The phase is operated in engine Between, high lift peach tip periodically pushes down on outer arm 120.Since outer arm 120 is locked on inner arm 122, so high lift Movement is transferred to inner arm 122 from outer arm 120 and is further diverted into valve 112.When rocker arm 100 is in its low lift mode, Outer arm 120 is not locked out on inner arm 122, therefore the high lift movement that outer arm 120 is presented is not transfer to inner arm 122.As Substitution, low lift peach tip contact with inner arm 122 and generate the low lifting movement for being transferred to valve 112.It is unlocked when from inner arm 122 When, outer arm 120 is pivoted around axis 118, but movement is not transferred to valve 112.

Figure 27 shows the perspective view of exemplary transformation rocker arm 100.Conversion rocker arm 100 is only illustrated by way of example, and And will be appreciated that, the configuration of the conversion rocker arm 100 as subject of the present invention is not limited to show in drawings contained herein The configuration of conversion rocker arm 100 out.

As shown in figure 27, conversion rocker arm 100 includes the outer arm 120 with the first outer webs 124 and the second outer webs 126. Inner arm 122 is arranged between the first outer webs 124 and the second outer webs 126.Both inner arm 122 and outer arm 120 are installed in position On pivot 118 near the first end 101 of rocker arm 100, inner arm 122 is fixed on outer arm 120 by the pivot, while also being permitted Perhaps relative to outer arm 120 around the rotary freedom of the pivot 118 of inner arm 122.Have shown in removing and is mounted on outer arm 120 and inner arm Outside the embodiment of individual pivot 118 on 122, pivot 118 can be a part of outer arm 120 or inner arm 122.

Rocker arm 100 shown in Figure 27 has the roller 128 for the low lift peach tip in center for being configured to three peach tip cams of engagement.Outside The first slide block pad 130 and the second slide block pad 132 of arm 120 are configured to engage the first high lift peach tip 104 and second shown in Fig. 4 High lift peach tip 106.First torque spring 134 and the second torque spring 136 are used for biased by high lift peach tip 104,106 Outer arm 120 after displacement.The rocker design provides spring excess revolutions moment characteristics.

The first overrun limiter 140 and the second overrun limiter 142 of outer arm prevent the excessive volume of torque spring 134,136 Excessive stresses in simultaneously limited spring 134,136.When outer arm 120 reaches its maximum rotation during low lift mode, surpass Journey limiter 140,142 contacts in the first oil duct 144 and the second oil duct 146 with inner arm 122.At this point, overrun limiter 140, Interference between 142 and channel 144,146 stops any of outer arm 120 and is further rotated down.Figure 28 shows oneself of rocker arm 100 View under.As shown in figure 28, excess of stroke limitation 140,142 is extended into logical with inner arm 122 from outer arm 120 towards inner arm 122 Road 144,146 is overlapped, so that it is guaranteed that the interference between limiter 140,142 and channel 144,146.As 29-29 is cut along indicating Shown in Figure 29 of the sectional view taken, the contact surface 143 of limiter 140 is in wave shape to match with the cross sectional shape in channel 144.This has Help distribute when limiter 140,142 and channel 144,146 are contacted using uniform power.

When outer arm 120 reaches its maximum rotation during low lift mode as described above, lock bolt backstop shown in figure 15 Portion 90 prevents lock bolt from stretching out and improperly locking.This feature can be configured to be suitble to the shape of outer arm 120 on demand.

Figure 27 shows the perspective view seen from above of rocker arm assembly 100, it is shown that a reality of introduction according to the present invention Apply the torque spring 134,136 of example.Figure 28 is the plan view of the rocker arm assembly 100 of Figure 27.The design shows to have and wind The rocker arm assembly 100 of torque spring 134,136 around holding shaft 118.

Convert rocker arm assembly 100 must it is sufficiently compact, with cooperate in limited engine space without sacrifice performance or Durability.In some embodiments, tradition made of the round wire winding from the torque request for being really sized to meet design is turned round Power spring is too wide and can not cooperate in the permission spring compartment 121 between outer arm 120 and inner arm 122 as shown in figure 28 In.

4.2 torque spring

Description causes the torque spring 134,136 of compact design using the general rectangular line made of selected structural material Design and manufacture method.

Now, with reference to Figure 15,28,30A and 30B, torque spring 134,136 is made of the generally trapezoidal shaped line 397 of shape. This is trapezoidal to be designed that line 397 to be deformed into exerting a force in winding process and be deformed into general rectangular.In torque spring 134,136 be wound after, the shape of obtained line can be described as and with general rectangular cross-sectional 396 phase of First Line Seemingly.The section of line 8 in Figure 28 shows in sectional view two torque spring realities shown in as multiple coils 398,399 Apply example.In a preferred embodiment, line 396 has rectangular cross sectional shape, has and is shown as the two long of vertical edge 402,404 herein Side and top 401 and bottom 403.The coil while 402 and while 404 average length and top 401 and bottom 403 be averaged Length ratio can be the arbitrary value less than 1.The ratio generates top 401 and bottom 403 than using diameter and coil 398 The spring of the equal round wire winding of average length is more along the rigidity of coil axis of bending 400.In alternative embodiments, line Cross sectional shape be generally trapezoidal with larger top 401 and smaller bottom 403.

In the configuration, as coil is wound, the long side 402 of each coil is rested in the long side 402 of previous coil, Thus stablize torque spring 134,136.All coils are maintained at stand up position by the shape and arragement construction, to prevent it Intersected with each other under stress or drift angle.

When rocker arm assembly 100 operate when, the general rectangular of torque spring 134,136 or it is trapezoidal due to they around Figure 30 A, Axis 400 shown in 30B and Figure 19 is bent and generates high local stress, especially the tensile stress on top surface 401.

In order to meet life requirement, it is used together the combination of technology and material.For example, torque spring 134,136 can be pressed It is made according to the design of the material comprising chrome alum steel alloy to improve intensity and durability.

Torque spring 134,136 can be heated and be quickly cooled down so that spring temper.It reduce residual local stresses.

The surface of the line 396,397 of torque spring 134,136 is used to form using ballistic impact or " shot-peening processing " is used to Residual compression stress is placed in the surface of line 396,397.Then by line 396,397 wound in torque spring 134,136.By Shot-peening in them is processed, and obtained torque spring 134,136 can receive now than without using the identical of shot-peening processing and manufacturing The bigger tensile stress of spring.

4.3 torque spring seats

Converting rocker arm assembly 100 can be sufficiently compact, thus to cooperate the smallest impact of surrounding structure in limited hair In motivation space.

It is described as torque spring seat and the conversion rocker arm 100 of the holding feature formed by adjacent component is provided.

Referring now to Figure 27,19,28 and 31, the component of outer arm 120 and inner arm 122 forms spring base as shown in figure 31 119.This includes the holding feature 119 of the one of the end of the torque spring 134,136 for Figure 19.

Torque spring 134,136 can be moved freely along the axis of pivot 118.When assembling has been completed, on inner arm 122 One tab 405 and the second tab 406 keep the inner end 409,410 of torque spring 134,136 respectively.The first surpassing on outer arm 120 Journey limiter 140 and the second overrun limiter 142, which are assembled into, to be prevented from rotating and the first torque spring 134 and second is kept to turn round respectively The outer end 407,408 of power spring 136, there is no extra limitation or additional materials and components.

4.4 outer arm

The design of outer arm 120 is optimized for expected specific load during operation, and its anti-bending strength It may cause ultra-specification flexure with by other devices or from the torque that other directions apply.The example of not operation load can be by operating Or processing causes.The clutch features or surface formed in components be designed to lapping sliders pad while assist clamp and Holding process, this is key step needed for keeping maintaining the depth of parallelism between slide block pad when components are static and indeformable at it Suddenly.Figure 15 shows another perspective view of rocker arm 100.First clamps peach tip 150 protrudes from the lower section of the first slide block pad 130.Second Clamp the lower section that peach tip (not shown) is similarly located in the second slide block pad 132.In the fabrication process, peach tip 150 is clamped in cunning It is engaged during the grinding of block pad 130,132 with fixture.It exerts a force to peach tip 150 is clamped, outer arm 120 is limited in by the clamping peach tip Appropriate location just looks like it as the components of rocker arm assembly 100 and is under assembled state the same.The grinding requirement on these surfaces The holding of pad 130,132 is parallel to each other and outer arm 120 is indeformable.It prevents from arranging in other clampings clamping to clamp at peach tip 150 The deformation that outer arm 120 may occur under structure.For example, being helped preferably being clamped at integral clamping peach tip 150 with outer arm 120 In any mechanical stress that elimination is occurred and being pressed toward each other the clamping of outer webs 124,126.In another example, it clamps Peach tip 150 is located at slide block pad 130,132 following location directly cause to generate on outer arm 120 due to the contact force with abrasive machine It is substantially zero minimum torque.In certain applications it may be necessary to which other positions into outer arm 120 apply pressure with maximum Reduce to limit deformation.

The operation of 4.5 DVVL components

Figure 19 shows the exploded view of the conversion rocker arm 100 of Figure 27 and 15.With reference to Figure 19 and 28, when assembled, roller 128 It is a part for rolling pin-like member 129, the rolling pin-like member can have the needle roller being mounted between roller 128 and roller bearing 182 180.Roller bearing 182 is mounted on inner arm 122 via roller bearing hole 183,184.Roller assembly 129 is used for low lift cams 108 Rotary motion be transferred to inner rocker arm 122, and in turn will movement be transferred to valve 112 in the unlocked state.Pivot 118 passes through Lantern ring 123 is mounted on inner arm 122 and is mounted on outer arm 120 in the first end of rocker arm 100 101 through pivot hole 160,162. Outer arm 120 rotates about pivot 118 relative to the hole of inner arm 122 in the unlocked state and occurs.Lost motion in this context moves It is dynamic to mean movement of the outer arm 120 in the unlocked state relative to inner arm 122.The movement will not be by cam in the unlocked state The rotary motion of 102 the first high lift peach tip 104 and the second high lift peach tip 106 is transmitted to valve 112.

Also allow to move from cam 102 and be transferred to rocker arm different from other configurations of roller assembly 129 and pad 130,132 100.For example, the smooth non-rotating face (not shown) of such as pad 130,1332 etc can be placed on inner arm 122 to engage low liter Journey peach tip 108, and roller assembly is mountable is transferred to rocker arm on rocker arm 100 will move from high lift peach tip 104,106 100 outer arm 120.

Now, with reference to Fig. 4,19 and 12, as described above, exemplary transformation rocker arm 100 uses three peach tip cams 102.

Compact to design in order to make, wherein dynamic load is as close with non-conversion formula rocker design as possible, uses slide block pad 130,132 as the surface contacted during high lift mode operation with nose 104,106.Slide block pad produces during operation The raw friction bigger than other designs of such as roller bearing etc, and the first slide block pad surface 130 and the first high lift peach tip Friction between surface 104 plus the friction between the second slide block pad 132 and the second high lift peach tip 106 form engine efficiency damage It loses.

When rocker arm assembly 100 is in high lift mode, whole loads of valve opening event be applied to slide block pad 130, 132.When rocker arm assembly 100 is in low lift mode, be applied to the load of the valve opening event of slide block pad 130,132 compared with It is small, but exist.The encapsulation limitation of exemplary transformation rocker arm 100 requires the slide block pad such as by contacting with nose 104,106 The width of each slide block pad 130,132 described in edge length 710,711 is narrower than most of existing sliding block interface.This causes The components load and stress higher than most of existing slide block pad interface.The friction causes to nose 104,106 With the excessive abrasion of slide block pad 130,132, and component failure in advance may cause when combining with higher load.? In exemplary transformation rocker arm assembly, the painting of carbon coating etc is bored using such as class in the slide block pad 130,132 on outer arm 120 Layer.

Class is bored carbon (DLC) coating and is realized by reducing friction come operation example conversion rocker arm 100, and at the same time being sliding block It pads surface 130,132 and necessary wear-resisting and load characteristic is provided.As being readily visible, the benefit of DLC coating be can be applied to Pivot surface 160 on any component surface in the component or other components, such as outer arm 120 described in Figure 19, 162。

Despite the presence of similar coating material and technique, but they are all insufficient for following DVVL rocker arm assembly requirement: 1) have enough hardness, 2) have suitable bearing capacity, 3) it is stable in chemistry in operating conditions, 4) be suitable for temperature In technique no more than the annealing temperature of outer arm 120,5) meet service life of aeroengine requirement and 6) with the steel on steel interface The friction reduced compared to offer.The DLC coating process being described above meets above-mentioned requirements, and be suitable for slide block pad surface 130, 132, using for the application and development of DLC coating emery wheel material and speed by the slide block pad surface grinding to final finish. Slide block pad surface 130,132 is also polished to particular surface roughness, such as steam honing or particle using one of several technologies Sandblasting.

4.5.1 hydraulic fluid system

Hydraulic lock bolt for rocker arm assembly 100 must manufacture into cooperation in compact space, when meeting transition response Between require, and to the maximum extent reduce pump oil loss.Oil is advanced with controlled pressure along fluid path, and starts lock bolt to provide The mode of power needed for pin conversion and speed is applied to controlled volume.Hydraulic pipeline needs specific gap and size, so that System have correct hydraulic stiffness and thus generate the transition response time.The design of hydraulic system must with include interpreter Other elements of structure such as biasing spring 230 is coordinated.

In conversion rocker arm 100, chamber and tunnel of the oil through array of fluid connection to lock bolt pin mechanism 201 or are appointed The what lock bolt pin mechanism of its hydraulic starting.As described above, hydraulic power transmission system starts from the oily flowing ports in DFHLA 110 506, the oily or another hydraulic fluid under controlled pressure is imported into herein.Conversion equipment such as solenoid valve can be used Modulated pressure.After leaving bulb stopper end 610, oily or other pressurized fluids have really from the single location through shown in Fig. 10 It is sized to reduce the first oil duct 144 of the above-mentioned inner arm of pressure drop when oil is flowed from ball-and-socket 502 and the second oil to the maximum extent Road 146 is directed into the lock bolt pin assemblies 201 in Figure 19.

For inner arm 122 is locked on outer arm 120 mechanism 201 --- it is located at rocker arm in an illustrated embodiment Near 100 second end 103 --- it is shown as including latch pin 200 in Figure 19, which stretches under high lift mode Out, so that inner arm 122 is fixed on outer arm 120.Under low lift mode, lock bolt 200 is returned in inner arm 122, to permit Perhaps the lost motion of outer arm 120 is mobile.Oil pressure is used to control latch pin 200 mobile.

As shown in figure 32, one embodiment of lock bolt pin assemblies shows oil duct 144,146 (being shown in FIG. 19) through oil Hole 280 and chamber 250 are in fluid communication.

Oil is provided to oilhole 280 and lock bolt pin assemblies 201 according to desired operation mode within the scope of certain pressure.

Visible such as in Figure 33, after the oil that will pressurize imports chamber 250, lock bolt 200 is returned in hole 240, thus Outer arm 120 is allowed to occur to rotate relative to the lost motion of inner arm 122.Oil can be on the first generally cylindrical surface 205 and surface 241 Between from chamber 250 be transferred to second chamber 420 shown in Figure 32.

Some holes 209 of the oil through drilling out in inner arm 122, which are left, returns to engine.Residual oil is as biasing spring 230 is at it It stretches when returning to the high lift state of locking and is pushed back through hydraulic path.It can be seen that can be biased to be operated for usual unlock Latch mechanism use similar flow path.

The design of lock bolt pin assemblies passes through gap, tolerance, pore size, chamber size, spring design and the flowing of control oil The latch pin response time is managed similar to the combination of measurement.For example, latch pin design may include such as being designed to movable liquid Intermediate pressure section with operated in the tolerance within the scope of given pressure double diameter pins, be designed to limitation pump oil loss oil sealing convex shoulder or To the feature structure of oil groove (chamfer oil in-feed) etc.

Referring now to Figure 32-34, lock bolt 200 includes that the design feature of multiple functions is provided in the confined space:

1. lock bolt 200 uses the first generally cylindrical surface 205 and the second generally cylindrical surface 206.First is substantially round Cylindrical surface 205 has the diameter bigger than the second generally cylindrical surface 206.When pin 200 and sleeve 210 assemble in hole 240 When together, chamber 250 is formed in the case where not using any additional components.It is, as noted, the volume and oilhole 280 It is in fluid communication.In addition, the area of pressing surfaces 422 and the oil pressure of transmitting, which can be controlled so as to provide, makes the movement of pin 200, compression Biasing spring 230 and power needed for being transformed into low lift mode (unlock).

2. the space between the first generally cylindrical surface 205 and adjacent hole wall 241 be intended to reduce to the maximum extent from The oil mass of the inflow second chamber 420 of chamber 250.Gap between first generally cylindrical surface 205 and surface 241 must be tight It thickly controls into when oil is transferred to second chamber 420 from chamber 250 between the first generally cylindrical surface 205 and surface 241 When allow the one-movement-freedom-degree of pin 200 may be not present oil leak and relevant pump oil loss.

3. encapsulation limitation requires the distance for reducing the mobile axis along pin 200 to the maximum extent.Under some operating conditions, Available oil sealing convex shoulder 424 may be not enough to control between the first generally cylindrical surface 205 and surface 241 from chamber 250 It is transferred to the flowing of the oil of second chamber 420.Annular seal surface is described.As lock bolt 200 is retracted, lock bolt 200 is with table thereafter It meets with hole wall 208 in face 203.In a preferred embodiment, the rear surface 203 of lock bolt 200 has big generally perpendicular to first Body cylindrical bore wall 241 and second substantially cylindrical bore wall 242 and is parallel to the planar annular or sealing surfaces 207 of hole wall 208. Flat annular surface 207 forms the sealing against hole wall 208, which reduce oil from chamber 250 via lock bolt 200 first substantially The seal leakage that cylindrical surface 205 and the first general cylindrical hole wall 241 are formed.The area of sealing surfaces 207 is determined Size separates resistance at caused by the thin oil film reduced shown in Figure 32 between sealing surfaces 207 and hole wall 208 to the maximum extent, The sealing for preventing pressurization oil from flowing between sealing surfaces 207 and hole wall 208 and exit orifice 209 is maintained simultaneously.

4. providing initial press surface region to such as groove of oil meter face 426 in 200 embodiment of latch pin to permit Perhaps conversion starting faster, and overcome and separate resistance as caused by the thin oil film between pressing surfaces 422 and sleeve ends 427. The size and angle of groove allow to convert the easiness started, without the oil pressure transformation due to encountering during usual operation Start without plan.In 200 embodiment of the second latch pin, a series of serrate slots for radially arranging as shown in figure 34 (castellation) 428 initial press surface region is provided, is sized to be permission conversion starting faster, and overcome Resistance is separated as caused by the thin oil film between pressing surfaces 422 and sleeve ends 427.

It can also be by reducing the requirement to the separating force between pressing surfaces 422 and sleeve ends 427 to oil meter face 426 To reduce the required pressure of conversion and pump oil loss.These relationships can be used as the incremental improvement that loss is inhaled to transition response and pump It shows.

As oil stream is all over above-mentioned 100 hydraulic system of conversion rocker arm assembly, between oil pressure and flow of oil path area and length Relationship largely define the reaction time of hydraulic system, this also directly affects the transition response time.For example, if High pressure oil under high-speed enters big space, then its rate will slow down suddenly, thus reduce its hydraulic reaction time or Reduce its rigidity.The range for being directed to these relationships of operation of conversion rocker arm assembly 100 can be calculated.For example, can be by one Kind relationship description is as follows: the oil under 2bar pressure is supplied to chamber 250, wherein passing through the oil pressure of pressing surfaces region segmentation Transmitting overcomes the power of the elastic force of biasing spring 230, and is transformed into unlock operation from lock operation in 10 milliseconds.

Can be calculated from the system design variables that can be defined as follows pump oil lose it is minimum cause it is acceptable it is hydraulic just The range of degree and the characteristic relation of response time:

The internal diameter of oil duct 144,146 and from ball-and-socket 502 to the length in hole 280

The diameter and length in hole 280

The area of pressing surfaces 422

In the volume of all mode of operation lower chambers 250

The volume of second chamber 420 under all modes of operation

The sectional area formed by the space between the first generally cylindrical surface 205 and surface 241

The length of oil sealing convex shoulder 424

The area of flat annular surface 207

The diameter in hole 209

The oil pressure supplied by DFHLA 110

The rigidity of biasing spring 230

The sectional area and length of flow channel 504,508,509

To the area and quantity of oil meter face 426

The quantity and sectional area of serrate slot 428

The lock bolt response time of the above-mentioned hydraulic device in rocker arm 100 can be converted for the description of a certain range of condition, Such as:

Oil temperature: 10 DEG C to 120 DEG C

Oil type: 5w-20 weight

These conditions have an impact the oil viscosity range of lock bolt response time.

4.5.2 lock bolt pin mechanism

The lock bolt pin mechanism 201 of rocker arm assembly 100, which is provided, to be transformed into low lift from high lift and is transformed into from low lift The mode of high lift.Lock bolt pin mechanism can be configured to be generally in unlocked state or lock state.It can describe several preferred Embodiment.

In one embodiment, it is used to inner arm 122 being locked in outer arm 120 near the second end 103 of rocker arm 100 On mechanism 201 be shown as including latch pin 200, sleeve 210, orienting pin 220 and lock pin spring 230 in Figure 19.Mechanism 201 are configured to be mounted on the inside of inner arm 122 in hole 240.As described below, in assembled rocker arm 100, lock bolt 200 exists It is stretched out under high lift mode, so that inner arm 122 is fixed on outer arm 120.Under low lift mode, lock bolt 200 returns to interior In arm 122, to allow the lost motion of outer arm 120 mobile.Conversion oil pressure as described above is through the first oil duct 144 and the second oil duct 146 are provided to control lock bolt 200 and be locked or unlock.Plug 170 is inserted into access opening 172 and closes the first oil duct to be formed 144 and second the densification of oil duct 146 seal and allow them that oil is transmitted to locking mechanism 201.

Figure 32 shows the sectional view of line 32,33-32,33 of the locking mechanism 201 in its lock state in Figure 28.Lock Door bolt 200 is arranged in hole 240.The spring eye 202 that there is lock bolt 200 biasing spring 230 to be inserted.Lock bolt 200 has rear table Face 203 and front surface 204.Lock bolt 200 also uses the first generally cylindrical surface 205 and the second generally cylindrical surface 206.The One generally cylindrical surface 205 has the diameter bigger than the second generally cylindrical surface 206.Spring eye 202 and surface 205 and 206 is generally concentric.

Sleeve 210 has general cylindrical inner surface 215 and the substantially cylinder with 241 interface of the first general cylindrical hole wall Shape outer surface 211.Hole 240 has the bigger than the first general cylindrical hole wall 241 of the first general cylindrical hole wall 241 and diameter Two general cylindrical hole walls 242.The general cylindrical outer surface 211 of sleeve 210 and the first generally cylindrical surface of lock bolt 200 205 engage the first general cylindrical hole walls 241 and form densification sealing.In addition, the general cylindrical inner surface 215 of sleeve 210 Also densification sealing is formed with the second generally cylindrical surface 206 of lock bolt 200.During operation, these sealings allow surrounding Oil pressure is formed in the chamber 250 of second generally cylindrical surface 206 of lock bolt 200.

The default location of lock bolt 200 shown in Figure 32 is latched position.Spring 230 is by lock bolt 200 from the outside bias in hole 240 To latched position.The oil pressure for being supplied to chamber 250 retracts lock bolt 200 and makes it move to unlocked position.Other configurations are also It is possible, such as the lock bolt 200 that 230 bias of spring is in the unlocked position, and apply between hole wall 208 and rear surface 203 Oil pressure keeps lock bolt 200 protruding to lock outer arm 120 from hole 240.

In the locked state, lock bolt 200 engages the latch surface 214 of outer arm 120 with arm joint surface 213.Such as Figure 32 institute Show, outer arm 120, which is obstructed, to be moved down and movement will be transferred to inner arm 122 through lock bolt 200.Alignment features structure 212 is in Then the form in channel, orienting pin 221 are prolonged from outside inner arm 122 through the first pin hole 217 through the second pin hole 218 in sleeve 210 It reaches in the channel.Orienting pin 221 is usually solid and smooth.Pin 221 is secured in place by locator 222.It is fixed Excessive rotation of the lock bolt 200 in hole 240 is prevented to pin 221.

As described above and in Figure 33 it is visible, will pressurize oil importing chamber 250 after, lock bolt 200 returns to hole 240 In, so that outer arm 120 be allowed to occur to rotate relative to the lost motion of inner arm 122.Outer arm 120 be then no longer removed 200 obstructions to Lower movement and progress lost motion are mobile.Pressurization oil imports in chamber 250 through oilhole 280, and the oilhole and oil duct 144,146 fluids connect It is logical.

Figure 35 A-35F shows several holding meanss for orienting pin.In Figure 35 A, pin 221 is cylindrical, has equal Even thickness.The snap ring 910 as shown in Figure 35 C is located in the recess portion 224 in sleeve 210.In 221 insertion ring 910 of pin, from And it deforms tooth 912 and pin 221 is fixed on ring 910.Then pin 221 is enclosed in recess portion 224 by inner arm 122 due to ring 910 It is interior and be fixed in position.In another embodiment shown in Figure 35 B, pin 221 has slot 902, and the tooth 912 of ring 910 is pressed Enter in the slot, so that ring 910 is fixed on pin 221.In another embodiment shown in Figure 35 D, pin 221 has slot 904, figure The E clevis 914 of type shown in 35E or the cramp frame 914 shown in Figure 35 F can be inserted into the slot relative to the general of inner arm 122 Pin 221 is secured in place.It is applicable to wire rings in yet other embodiments, instead of punching ring.During assembly, will E clevis 914 is put into recess portion 224, and sleeve 210 is inserted into inner arm 122 at this time, then passes through 910 insertion orienting pin 221 of folder.

Exemplary lock bolt 200 is shown in FIG. 36.Lock bolt 200 is generally divided into head 290 and body portion 292.Front surface 204 is Convex curved surface outstanding.The surface shape extends towards outer arm 120 and makes arm joint surface 213 and the outer arm 120 of lock bolt 200 The probability suitably engaged improves.Arm joint surface 213 includes generally flat surface.Substantially justify from second on arm joint surface 213 First boundary 285 of cylindrical surface 206 extends to the second boundary 286, and extends to from the boundary 287 with front surface with table The boundary 233 in face 232.The portion for extending at most along the direction of the longitudinal axis A of lock bolt 200 from surface 232 on arm joint surface 213 Divide substantially equally between the first boundary 285 and the second boundary 286.On the contrary, arm joint surface 213 from surface 232 along axis Line direction A extend least part is located substantially at the first boundary 285 and the second boundary 286.Front surface 204 is not necessarily protrusion Curved surface, but can be v-shaped surface or some other shape.The arragement construction allow lock bolt 200 in hole 240 more A possibility that large-scale to rotate, while the arm joint surface 213 for improving lock bolt 200 is suitably engaged with outer arm 120.

Alternative locking mechanism 201 is shown in FIG. 37.Orientation plug 1000 in hollow cupuliform plug form is by prolonging Reach in alignment features 212 and be press-fitted in sleeve hole 1002 and orient lock bolt 200, thus prevent lock bolt 200 relative to Sleeve 210 excessively rotates.As further described, locating slot 1004 is by providing available so that lock bolt 200 is in sleeve 210 Lock bolt 200 is oriented in sleeve 210 to assist and is ultimately oriented in inner arm 122 by the feature structure of interior rotation.Locating slot 1004 can be used as the feature structure to make the rotation of lock bolt 200 and also to measure its relative orientation.

With reference to Figure 38-40, the illustrative methods of assembling conversion rocker arm 100 are as follows: orientation plug 1000 is press-fitted in set It is inserted into the general cylindrical inner surface 215 of sleeve 210 in bore 1002 and by lock bolt 200.

Then rotate clockwise latch pin 200, until alignment features structure 212 reaches plug 1000, orientation is special at this time Interference prevention between sign structure 212 and plug 1000 further rotates.Then angle measurement A1 as shown in figure 38 is obtained, It corresponds to the angle between arm joint surface 213 and the sleeve datum level 1010,1012 for being positioned perpendicularly to sleeve hole 1002.It is fixed Position slot 1004 also serves as the reference line for lock bolt 200, and keyway 1014 also is used as the benchmark being located on sleeve 210.Lock The then rotation counterclockwise of rod bolt 200, until alignment features structure 212 reaches plug 1000, to prevent from further rotating.Such as exist As it can be seen that obtaining second angle measured value A2 in Figure 39, correspond between joint surface 213 and sleeve datum level 1010,1012 Angle.Also allow to rotate and then rotate clockwise to obtain A1 and A2 counterclockwise.As shown in figure 40, after being inserted into inner arm 122, set Cylinder 210 and pin assemblies 1200 are rotated with the angle A measured between inner arm datum level 1020 and sleeve datum level 1010,1012, So that arm joint surface 213 is horizontally oriented relative to inner arm 122, as shown in inner arm datum level 1020.Rotation amount A should be selected It is selected to improve a possibility that lock bolt 200 will engage outer arm 120 to the maximum extent.One such example be make sub-component 1200 with The angle of the half of the difference of the A2 and A1 that such as measure from inner arm datum level 1020 rotates.Within the scope of the invention, other adjustings It is possible for measuring A.

The profile of the alternate embodiment of pin 1000 is shown in FIG. 41.Here, pin 1000 is hollow, is partly closed Internal volume 1050.The pin has the first substantial cylindrical wall 1030 and the second substantial cylindrical wall 1040.It is substantial cylindrical The first wall 1030 have the diameter D1 bigger than the diameter D2 of the second wall 1040.In one embodiment shown in Figure 41, flange 1025, which are used to banking pin 100, moves downwards through the pin hole 218 in sleeve 210.In the second embodiment shown in Figure 42, press-fitting It closes banking pin 1000 and moves downwards through the pin hole 218 in sleeve 210.

4.6DVVL pack clearance management

Describe to manage three or more gap widths or design gaps in DVVL conversion rocker arm assembly 100 shown in Fig. 4 Method.This method may include range, wear allowance and the design profile of nose/rocker arm contact surface manufacturing tolerance.

The description of DVVL pack clearance

Exemplary rocker arm component 100 shown in Fig. 4 has one for must be maintained at one or more positions in component Or multiple gap widths.Three peach tips cam 102 shown in Fig. 4 is by three noses --- i.e. the first high lift peach tip 104, second High lift peach tip 106 and low lift peach tip 108 --- composition.Nose 104,106 and 108 is big by respectively including being described as The profile composition of round and concentric with the camshaft basic circle 605,607,609 of body.

Conversion rocker arm assembly 100 shown in Fig. 4 is designed to have small―gap suture (gap) two positions.Shown in Figure 43 First position is lock bolt gap 602, i.e. lock bolt pads the distance between surface 214 and arm joint surface 213.Lock bolt gap 602 ensures Lock bolt 200 is not loaded and can be moved freely when converting between high lift mode and low lift mode.Such as Fig. 4,27,43 Shown in 49, second example in gap --- i.e. between the first slide block pad 130 and the first high-lift cam peach tip basic circle 605 away from From --- it is illustrated as cam shaft clearance 610.The roller 128 shown in Figure 49 of cam shaft clearance 610 is during low lift operation Slide block pad 130,132 and their own high-lift cam peach tip basic circle are eliminated when contacting with low lift cams basic circle 609 605, friction loss for the contact and amplification between 607.

During low lift mode, cam shaft clearance 610 also prevents the elastic force of torque spring 134,136 from grasping in basic circle 609 DFHLA 110 is transmitted to during work.This allows DFHLA 110 as the backlash compensation part of wherein DFHLA is from engine oil pressure The standard rocker arm assembly with the compensation of usual hydraulic lash that channel is directly fed equally operates.As shown in figure 47, the movement by The rotation stopper section 621,623 converted in rocker arm assembly 100 promotes, and the rotation stopper section prevents outer arm 120 due to torsion bullet The elastic force of spring 134,136 and rotate enough to mostly to be contacted with high lift peach tip 104,106.

As shown in Figure 43 and 48, overall mechanical gap is the sum of cam shaft clearance 610 and lock bolt gap 602.It should and influence valve Movement.High-lift cam axis profile includes the opening and closing oblique line 661 for compensating overall mechanical gap 612.Overall mechanical gap 612 minimum change is critically important for maintaining performance objective through the service life of engine.In order to which gap is maintained at specific In range, 612 tolerance of overall mechanical gap is closely controlled during manufacturing.Since the variation in component wear and overall mechanical gap is closed Connection, so the service life through mechanism allows low-level component wear.The durability of extension shows the wear allowance of distribution and total Mechanical clearance is maintained in specified limits at the end of life test.

The profile diagram referring to shown in Figure 48, gap in millimeters are located on vertical axis, and as unit of degree Camshaft angle is arranged on a horizontal axis.The linear segment 661 of valve lift profile 660 shows the given change for camshaft angle Constant distance variation for change in millimeters, and represent the region of the closure constant rate between contact surface.For example, During the linear segment 661 of valve lift profile 660, when rocker arm assembly 100 (Fig. 4) is transformed into high lift from low lift mode When mode, the closing distance between the first slide block pad 130 and the first high lift peach tip 104 (Figure 43) represents constant rate of speed.It utilizes The constant rate of speed region reduces the impact load due to caused by accelerating.

As shown in figure 48, without lift part 661 valve liter does not occur for valve lift profile 660 during constant rate of speed Journey.If reducing or closely controlling total backlash, valve lift profile by the design of improved system, manufacture or assemble method Linear velocity part needed for time quantum reduce, to provide engine management benefit, for example, allow valve lead or The constant valve of engine operates.

Now, referring to Figure 43,47 and 48, design and assembling variation for each components and sub-component can produce full The matrix of the gap width of constant number needed for foot converts timing specification and reduces above-mentioned transition region.For example, a latch pin The feature structure in 10 microns of minimum lock bolt gap 602 is needed when 200 self-aligned embodiments may include work.It is configured to not have The improved remodeling lock bolt 200 of self-aligned feature structure may be designed to need 5 microns of lock bolt gap 602.The design variation will Total backlash reduces 5 microns, and reduces needed for valve lift profile 660 without lift part 661.

For using any design of the conversion rocker arm assembly 100 of Fig. 4 of other methods contacted with three peach tip cams 102 For variation, cam shaft clearance 610 shown in lock bolt gap 602 and Figure 43 can be described in a similar way.Implement at one In example, roller 128 (Figure 15 and 27) is replaced using the sliding mats similar to 130.In a second embodiment, using similar to 128 Roller replace slide block pad 130 and slide block pad 132.There is also the other embodiments with roller and sliding block combination.

Gap management, test

As described in following chapters and sections, range test to expected operating condition and examine for managing gap Method is designed and manufactured to simulate usually operation and represent both states of more high-stress state.

By proving that lasting performance (that is, valve suitably opens and closes) turns to assess DVVL in conjunction with wear measurement Change the durability of rocker arm.By quantifying the machine in the material on DVVL conversion rocker arm, the specifically loss and system of DLC coating The relative quantity in tool gap is worn to assess.As described above, lock bolt gap 602 (Figure 43) is for allowing latch pin in inner arm and outer arm Between to move to realize in engine electronic control unit (ECU) order for high lift and two kinds of low lift operatings be necessary 's.On DVVL conversion rocker arm due to any caused by gap increase all reduce the (figure of available no lift oblique line 661 48), so as to cause the high acceleration of valve mechanism.The specification of abrasion relative to mechanical clearance is configured to allow to limit zero Component manufacture is at maintaining desired dynamic property in end-of-life.

For example, as shown in figure 43, the abrasion between contact surface in rocker arm assembly will change lock bolt gap 602, camshaft Gap 610 and obtained total backlash.The abrasion that these analog values can be will affect is described as follows: 1) roller 128 (Figure 15) with it is convex The abrasion of interface between wheel peach tip 108 (Fig. 4) reduces total backlash, 2) slide block pad 130,132 (Figure 15) and nose 104, the sliding interface between 106 (Fig. 4) increases total backlash and 3) lock bolt 200 and lock bolt pad surface 214 between abrasion increase Total backlash is added.Since bearing interface abrasion reduction total backlash and lock bolt and the abrasion of sliding block section increase total backlash, so total grind Damage can cause the net total backlash variation of the bottom line in the service life through rocker arm assembly.

4.7 DVVL component dynamic properties

Distribution of weight, rigidity and the inertia of conventional rocker have been directed to specified with dynamic stability during operation, gas Door rod head load and the relevant service speed of valve spring-compressed and the range of reaction force are optimized.It is shown in Fig. 4 to show Example property conversion rocker arm 100 has design requirement identical with conventional rocker, and other limitations are by the increased quality of component and conversion Function applies.It must also consider other factors, including be impacted due to caused by mode transcription error and sub-component functional requirement Load.Reduce quality and inertia but not operatively solves material needed for maintaining the rigidity of structure and resisting the stress in key area The design of distribution can cause the components for falling short of specifications or becoming over compression, both of which be may cause it is undesirable The condition of conversion performance and components failure in advance.DVVL rocker arm assembly 100 shown in Fig. 4 must dynamically be stabilized to low 3500rpm under the lift mode and 7300rpm under high lift mode is to meet performance requirement.

Referring to Fig. 4,15,19 and 27, the rigid of DVVL rocker arm assembly 100 is assessed under low lift and high lift both of which Degree.Under low lift mode, 122 transmission force of inner arm is to open valve 112.The engine encapsulation volume limit and interior of inner arm 122 The functional parameter of arm 122 does not need the structure of height optimization, because inner arm rigidity is greater than the fixed rocker arm for same application. Under high lift mode, outer arm 120 is cooperated with inner arm 122 to transmit the power for being used to open valve 112.Finite element analysis (FEA) Technology shows that outer arm 120 is most compatible component, as shown the exemplary diagram in maximum vertical amount of deflection region 670 in Figure 50 Shown in showing.Mass Distribution and stiffness optimization for the components concentrate on increasing outer arm 120 in slide block pad 130,132 and lock In vertical cross section height between door bolt 200.Outer arm 120 and high lift peach are based on to the design limitation of the top profile of outer arm 120 Gap between the swept profile of point 104,106.The design limitation of the profile of outer arm 120 is based in low lift mode Lower and cotter seat 116 gap.Optimize material distribution reduces vertical deflection and improves in the design limitation Rigidity improves 33% or more in one example compared with initial designs.

As shown in Figure 15 and 52, DVVL rocker arm assembly 100 is designed to pass through with it as far as possible towards 101 bias group of side The quality of part and around the bulb stopper contact point 611 of DFHLA 110 pivot when reduce inertia to the maximum extent.This cause two quality compared with Big component --- i.e. pivot 118 and torque spring 134,136 --- is located at the substantially cloth near DFHLA 110 in side 101 It sets.In the case where pivot 118 is in the position, lock bolt 200 is located at the end 103 of DVVL rocker arm assembly 100.

Figure 55 is that the rigidity by DVVL rocker arm assembly 100 under high lift mode is compared with other standard rocker arms Figure.DVVL rocker arm assembly 100 has the rigidity lower than the fixed rocker arm for the application, however, its rigidity is in and is used for In the existing range of rocker arm in currently manufactured similar valve mechanism configuration.The inertia of DVVL rocker arm assembly 100 is fixed The inertia of rocker arm approximately twice as however, its inertia is only slightly higher than in currently manufactured similar valve mechanism configuration The average value of rocker arm.The total effective mass for the inlet valve mechanism being made of multiple DVVL rocker arm assemblies 100 is than fixed inlet valve Mechanism is big by 28%.These rigidity, quality and inertia values needs optimize to meet operational design each component and sub-component Ensure lowest inertia and maximum rigidity while standard.

4.7.1 DVVL group dynamics performance is described in detail

The main member of total inertia including rocker arm assembly 100 is shown in Figure 53.These components be interior arm component 622, Outer arm 120 and torque spring 134,136.As described above, the functional requirement of interior arm component 622, for example, its hydraulic fluid transmission path Diameter and its latch pin mechanism shell, need the structure firmer than the fixed rocker arm for same application.In the following description, Interior arm component 622 is considered as single components.

The top view of the rocker arm assembly 100 in Fig. 4 is shown referring to Figure 51-53, Figure 51.Figure 52 is the line 52- in Figure 51 52 cross-sectional view shows the load contact point of rocker arm assembly 100.Three peach tip cams 102 of rotation are to roller 128 or according to behaviour Operation mode is to slide block pad 130,132 distributor loads 616.Bulb stopper end 601 and valve tip 613 provide opposite power.

Under low lift mode, cam load 616 is transmitted to valve tip 613 by interior arm component 622, (Fig. 4's) compression Spring 114, and open valve 112.Under high lift mode, outer arm 120 and interior arm component 622 are locked in together.This feelings Under condition, cam load 616 will be transmitted to valve tip 613, compressed spring 114 by outer arm 120, and open valve 121.

Referring now to Figure 4 and 52, total inertia of rocker arm assembly 100 is revolved by the main member at it around bulb stopper contact point 611 The sum of inertia of the calculated main member determines when turning.In exemplary rocker arm component 100, main member be may be defined as Torque spring 134,136, interior arm component 622 and outer arm 120.When total inertia increases, the dynamic load on valve tip 613 increases Greatly, and system dynamic stability reduces.It is moved to reduce valve tip load to the maximum extent and improve to the maximum extent State stability, the quality of entire rocker arm assembly 100 is by towards 611 bias of bulb stopper contact point.The quality that can be biased is given convex The requirement rigidity limitation of rocker arm assembly 100 needed for wheel load 616, valve tip load 614 and bulb stopper load 615.

Referring now to Figure 4 and 52, the rigidity of rocker arm assembly 100 is in promotion at them by interior arm component 622 and outer arm 120 Composite rigidity when journey or low lift condition determines.The rigidity value of any given position on rocker arm assembly 100 can use Finite element analysis (FEA) or other analysis methods come calculate with it is clear, and in the relational graph of rigidity and position along measurement axis 618 Middle characterization.In a similar way, the rigidity of outer arm 120 and interior arm component 622 can use finite element analysis (FEA) or other points Analysis method calculate separately with it is clear.Graphical representation of exemplary 106 measures axis 618 as the result is shown by what these were analyzed for a series of edges Rigidity and position feature relational graph.As above-mentioned additional illustration, Figure 50 shows the maximum defluxion figure of outer arm 120.

Referring now to Figure 52 and 56, the stress and amount of deflection of any given position on rocker arm assembly 100 can use limited Meta analysis (FEA) or other analysis methods calculate, and are characterized as being along negative for given cam load 616, valve tip The stress of the measurement axis 618 of lotus 614 and bulb stopper load 615 and the relational graph of amount of deflection and position.In a similar way, outer arm 120 and the stress and amount of deflection of interior arm component 622 can use finite element analysis (FEA) or other analysis methods are calculated separately and shown Change.Graphical representation of exemplary in Figure 56 is used to give cam load 616, valve stem as the result is shown by what these were analyzed for a series of edges The stress of the measurement axis 618 of head load 614 and bulb stopper load 615 and the Attributed Relational Graps of amount of deflection and position.

4.7.2 DVVL group dynamics performance evaluation

Stress and amount of deflection are analyzed, describe load condition in terms of load position and size as shown in figure 50.For example, In the rocker arm assembly 100 of the locking under high lift mode, cam load 616 is applied to slide block pad 130,132.Cam is negative Lotus 616 and valve tip load 614 and bulb stopper load 615 are opposite.First distance 632 is along valve tip load 614 and bulb stopper The distance that measurement axis 618 between load 615 measures.Second distance 634 is along valve tip load 614 and cam load The distance that measurement axis 618 between 616 measures.Duty ratio is second distance 634 divided by first distance 632.In order to be moved Mechanical analysis considers multiple values and operating condition for analysis and possible optimization.These may include three peach tip camshaft interfaces ginseng Number, torque spring parameter, overall mechanical gap, inertia, valve spring constant and DFHLA parameter.

Design parameter for assessment can be described:

Referring now to Fig. 4,51,52,53 and 54, describe to be typically designed method based on one group of given design parameter.

1. in step 350, along measurement axis arrangement component 622,120,134 and 136 with towards 611 bias of bulb stopper contact point Quality.For example, torque spring 134,136 can be located at the left 2mm of bulb stopper contact point, and the pivot in interior arm component 622 118 can be located at the 5mm of right.Outer arm 120 is positioned to be aligned with pivot 118 as shown in figure 53.

2. calculating total inertia of rocker arm assembly 100 for given component arrangement in step 351.

3. in step 352, assessing the function of component arragement construction.For example, confirmation torque spring 134,136 can be at it Designated position provide needed for rigidity to keep slide block pad 130,132 to contact with cam 102 without increase quality.Another In example, component arrangement be must determine as cooperation in package dimension limitation.

4. in step 353, the result of appraisal procedure 351 and step 352.If being unsatisfactory for turning in selected engine The minimum requirements of valve tip load 614 and dynamic stability under speed, the then repeatedly arragement construction of component and again in step Analysis is executed in 351 and 352.When satisfaction is to the valve tip load 614 and dynamic stability under selected engine speed Minimum requirements when, calculate rocker arm assembly 100 amount of deflection and stress.

5. calculating stress and amount of deflection in step 354.

6. assessing amount of deflection and stress in step 356.If being unsatisfactory for the minimum requirements to amount of deflection and stress, it is transferred to Step 355, and component design is improved.When design iteration is completed, return step 353 simultaneously reappraises valve tip load 614 And dynamic stability.When meet under selected engine speed valve tip load 614 and dynamic stability it is minimum It is required that when, amount of deflection and stress are calculated in step 354.

7. referring to Figure 55, when meeting the condition of stress, amount of deflection and dynamic stability, result is a kind of feasible design 357.It can be that feasible design configuration shows analysis result in the curve graph of rigidity and the relationship of inertia.The curve graph provides such as The range of acceptable value shown in region 360.Figure 57 shows three discrete acceptable designs.For amplification, it is subjected to Inertia/stiffness region 360 also define the characteristic of each main member 120,622 and torque spring 134,136.

Referring now to Fig. 4,52,55, if each component of master rocker component 100 --- including outer arm 120, interior arm component 622 and torque spring 134,136 --- collective meets the specific design criteria of inertia, stress and amount of deflection, then reach as described above Successful design.Successfully design generates the unique property data for being used for each main member.

In order to illustrate selection meets the DVVL rocker arm assembly of three work shown in certain stiffness/inertia standard Figure 57 100.Each of these components are all made of three main members: torque spring 134,136, outer arm 120 and interior arm component 622.In order to carry out the analysis, as shown in the graphical representation of exemplary of Figure 58, the possibility for each main member can be described Inertia values range:

Torque spring group designs #1, inertia=A；Torque spring group designs #2, inertia=B；Torque spring group, if Count #3, inertia=C.

Around bulb stopper end (also being indicated with X in Figure 59) calculated torque spring group inertia range by value A, The range determined in B and C defines.

Outer arm designs #1, inertia=D；Outer arm designs #2, inertia=E；Outer arm designs #3, inertia=F.

Calculated outer arm inertia range is by value D, E and F around bulb stopper end (also being indicated with X in Figure 59) Determining range defines.

Interior arm component designs #1, inertia=X；Interior arm component designs #2, inertia=Y；Interior arm component designs #3, is used to Property=Z.

Calculated interior arm component inertia range is by value X, Y around bulb stopper end (also being indicated with X in Figure 59) It is defined with the range determined in Z.

The range of the component inertia values generates the unique arrangement knot of main member (torque spring, outer arm and interior arm component) again Structure.For example, in this design, torque spring will tend to be very close with bulb stopper end 611.

With reference to Figure 57-61, it is closely related to the burden requirement in the calculating and component of the inertia of each component, because to most The expectation for reducing to limits inertia requires the Mass Distribution in optimization components to manage the stress in key area.For upper For stating each design in three kinds of successful designs, the range of rigidity value and Mass Distribution can be described.

For outer arm 120 design #1, can start at the end A and be extended to the end B show Mass Distribution with along the components The relationship of distance.It is also possible to show the Mass Distribution value that outer arm 120 designs #2 and outer arm 120 designs #3.

Region between two extreme mass distribution curves can be defined as the characteristic value of the outer arm 120 in the component Range.

For outer arm 120 design #1, can start at the end A and be extended to the end B show Stiffness Distribution with along the components The relationship of distance.It is also possible to show the rigidity value that outer arm 120 designs #2 and outer arm 120 designs #3.

Region between two extreme Stiffness Distribution profiles can be defined as the characteristic value of the outer arm 120 in the component Range.

The edge of outer arm 120 and the rigidity and Mass Distribution of its movement during operation and the related axis of orientation embody Character shape for characteristic value and amplification.

5 designs are examined

The response of 5.1 lock bolts

The lock bolt response time of exemplary DVVL system is verified, using lock bolt response test platform 900 shown in Figure 62 with true Rocker arm assembly is protected to convert in the predetermined mechanical switch window for being described above and being shown in FIG. 26.To from 10 DEG C to 120 DEG C In the range of the oil temperature recording responses time, to realize that oil viscosity varies with temperature.

Lock bolt response test platform 900 utilizes the manufacture hardware for including OCV, DFHLA and DVVL conversion rocker arm 100.In order to Simulated engine oil condition controls oil temperature by outside heating and cooling system.Oil pressure is supplied by external pump and utilizes adjusting Device control.Oil temperature is measured in the control channel between OCV and DFHLA.Lock bolt is measured using displacement sensor 901 to move It is dynamic.

The lock bolt response time is measured using a variety of manufacture SRFF.It is tested using manufacture with 5w-20 machine oil.From low Recording responses time when lift mode is transformed into high lift mode and is transformed into low lift mode from high lift mode.

Lock bolt response time when being transformed into high lift mode from low lift mode is shown in detail in Figure 21.It is surveyed at 20 DEG C Maximum response time is measured less than 10 milliseconds.Machinery when being transformed into low lift mode from high lift mode is shown in detail in Figure 22 Response time.Maximum response time is measured at 20 DEG C less than 10 milliseconds.

Study on the transformation the result shows that, the conversion time of lock bolt due to oil viscosity variation and depend primarily on oil temperature.Lock The gradient for fastening response curve with a bolt or latch is similar to the viscosity and temperature relation of machine oil.

Transition response the result shows that, lock bolt is mobile in a camshaft is turn-taked at 3500 engine rpm of highest It is sufficiently fast for carry out mode conversion.Response time starts to drop to 20 DEG C or less with temperature and dramatically increase.10 DEG C with Under temperature, in the case where not reducing 3500rpm conversion requirements, it is impossible to turn-take interior completion conversion in a camshaft.

SRFF is designed at high engine speeds for high lift as shown in Table 1 and low lift both of which It is reliable.High lift mode can be operated at highest 7300rpm, wherein " outburst " rate request is 7500rpm.Outburst is fixed Justice is that short time deviation is higher engine speed.SRFF is usually locked under high lift mode, so that high lift mould Formula is independent of oil temperature.Low lift operation mode is absorbed in the fuel economy during the sub-load operating of highest 3500rpm, Wherein in addition to the outburst revolving speed of 7500rpm, hypervelocity requires to be 5000rpm.As test as, the system can at 20 DEG C or with On oil temperature under hydraulically unlock SRFF.It is tested at 10 DEG C or less to ensure to operate at 20 DEG C.Durability results show The design is reliable within the scope of all operationss of engine speed, lift mode and oil temperature.

Table 1

Design, exploitation and the verifying of the DVVL system based on SRFF are completed to II type valve mechanism to realize that inlet valve mentions Preceding closing.The DVVL system improves fuel economy in the case where not damaging performance and operating in both modes. Pump is reduced and closing inlet valve in advance under low lift mode and inhales circulation loss, and standard is utilized under high lift mode Inlet valve profile and maintain performance.The system maintain in in-line four cylinder petrol engine shared II type inlet valve and Exhaust valve mechanism geometry.Implementation cost is reduced to the maximum extent using shared component and standard chain drive system. Utilizing the system based on II type SRFF by this method allows the hardware adaptations in multiple power teams.

The DVVL system being mounted on the inlet valve of valve mechanism meets under high lift and low lift both of which The Key performance targets of mode conversion and dynamic stability.The transition response time allows the oil temperature and highest at 20 DEG C or more It turn-takes interior carry out mode conversion under the engine speed of 3500rpm in a cam.The optimization of SRFF rigidity and inertia and suitable Valve lift profile design permission system 3500rpm is dynamically stabilized under low lift mode, and under high lift mode Dynamically stabilize to 7300rpm.Show that the DVVL system has been more than durability mesh with the validation test completed on hardware in manufacture Mark.The durability more than lifetime goal is proved using acceleration system degradation.

5.2 durability

Passenger car needs to meet 150,000 miles of effective discharge life requirements.This research sets 200,000 miles Tightened up target, to ensure the degree of reliability of product considerably beyond legal requirements.

200,000 miles of targets are converted to the valve mechanism requirement that life test terminates.The mileage target must convert It is air door operation event to define valve mechanism life requirement.In order to determine the quantity of valve event, it is necessary to assuming that in vehicle Average speed and engine speed in service life.For this example, for 40 miles per hour of selection of passenger car application Average speed and 2200rpm mean engine revolving speed.Camshaft speed is the half of engine speed and camshaft revolves The valve that turns around is primary by operation, to generate the test requirements document of 3.3 hundred million valve events.Engine and non-operating to operating Fixation device tested.Instead of running 5000 hours engine field investigations, most of test and report result are concentrated on To carry out test needed for meeting 3.3 hundred million valve events in the non-use for operating fixed device shown in Figure 63.Will operating and The result of non-field investigation is compared, and result and related valve mechanism abrasion mechanism are corresponding well, to provide The non-confidence level for operating fixed device lifetime test.

5.2.1 accelerated ageing

It needs to carry out accelerated test before running engine test to show the compliance to multiple engine lives.Cause This, executes fixed device to test before field investigation.Higher speed test be designed to accelerate valve mechanism abrasion so that It can be completed within the shorter time.Test association is established so that will averagely send out relative to the revolving speed in generated use Motivation revolving speed doubles to cause that the time is about 1/10th and valve mechanism abrasion is almost equal.As a result, valve mechanism abrasion is stringent Follow following formula:

Wherein VE_AccelFor the valve event needed for during accelerated aging test, VE_in-useFor usually using institute during test The valve event needed, RPM_avg-testFor the mean engine revolving speed of accelerated test, and RPM_{avg-in use}To use being averaged for test Engine speed.

Develop the specialized high-speed durability test circulation of the mean engine revolving speed with about 5000rpm.Respectively circulate in The high revolving speed duration under high lift mode is about 60 minutes, when the next relatively slow-speed of revolution under low lift mode continues Between be another about 10 minutes.Make the circulating repetition 430 times with realize 3.3 hundred million events being equivalent in the case where gauge load is horizontal 72,000,000 valve events under accelerated wear test speed.Standard valve mechanism product comprising needle bearing and roller bearing is for many years To be successfully used to automobile industry.The test cycle is directed to the slide block pad for being coated with DLC, wherein under high lift mode about 97% valve lift event is located in slide block pad, follows to complete 2,000,000 on low lift roller bearing as shown in table 2 Ring.These test conditions consider a valve mechanism service life for being equivalent to 430 accelerated tests circulation.Test shows SRFF's Sustainable six service life of aeroengine of durability, wherein abrasion and gap variation are negligible.

Table 2: durability test, valve event and target

Acceleration system degradation is crucial for showing durability, while completing many Special tests also with aobvious Show the reliability under various operating conditions.

Table 2 includes main durability test and the target respectively tested.Described above is acceleration system degradations, it is shown that About 500 hours or about 430 test cycles.Transfer test is set to run about 500 hours to assess lock bolt and torque spring abrasion.Together Sample is being partially blocked harshly transformation so that outer arm will skip the low lift mode phase during high lift event from outer arm Between also execute critical transitions test further to make components aging.Critical transitions test is carried out to be shown in incorrect vehicle Reliability in the case where extreme condition caused by safeguarding.Critical transitions test is difficult to realize and requires the essence in laboratory True oil pressure cntrol is partly to lock outer arm.Inexpectancy in use operation, because oil control pressure is controlled in the window Except.Multiple idle running tests and cold start operation are carried out with the accelerated wear test due to low oil lubrication.Also used at high speed The oil test crossed.Finally, carrying out bearing and torque spring test to ensure component durability.All tests all meet 200,000 The service life requirement of mile, the requirement are required safely above 150,000 miles of passenger car service life.

Carry out all durability tests with specific oily aeration level.Most of test has for passenger car application For oil aeration between common about 15% and 20% total gas content (TGC) it is horizontal.The content is with engine Rotation speed change and engine speed from idling to 7500rpm are by the level quantization.Also carry out having the oil of 26%TGC to expose The flat excessive oil aeration test of air water.These examinations are carried out using the SRFF met the requirements for dynamic and conversion performance experimental test It tests.The details of Dynamic performance examination illustrates in result chapters and sections.The oily gentle extension hydraulic test of water aeration is carried out to show product Reliability.

5.2.2 durability test device

Endurance test bed shown in Figure 63 is sent out by tetra- cylinder of prototype 2.5L with outer Oil-temperature control system 905 Motivation composition, the engine is by motor drive.Camshaft location is by passing through outside bent shaft-driven Accu-coder 802S Encoder 902 monitors.The angular speed of crankshaft is measured using digital magnetic velocity sensor (model Honeywell584) 904.Benefit With the oil pressure in Kulite XTL piezoelectric pressure indicator monitoring both control channel and hydraulic channel.

5.2.3 durability test device controls

Control system for fixing device is configured to order engine speed, oil temperature and valve lift state and examines The expected lift function of no satisfaction.By utilizing 906 measurement valve position of non-intrusion type Bentley Nevada3300XL short range probe The performance of in-migration assessment valve mechanism.Short range probe measures valve stroke under maximum half camshaft angle resolution ratio. This provides confirmation valve lift state and post-processing for information needed for shutdown rate and the data of rebound analysis.Test Setting includes the baseline state recorded under idling to indicate SRFF and the valve position for being used to determine main outline 908 shown in Figure 64 Move curve.

Figure 17 illustrates that the system diagnostics window of a conversion cycle for diagnosing valve-closing displacement.Control system OCV is ordered, so as to cause the movement of the OCV armature as shown in OCV current curve 881.In the pressure in the downstream OCV in oily control channel Power is increased as shown in pressure curve 880；Thus, operation latch pin causes to switch from high lift to the state of low lift.

Figure 64 shows the relationship of valve-closing tolerance 909 with the main outline 908 being determined by experiment.It is close used in calibration To measure the lift of last 2mm, final 1.2mm stroke is shown journey probe 906 on the vertical axis in Figure 64.In main outline 908 surroundings establish 2.5 " camshaft angle tolerance, to allow valve mechanism at high engine speeds to compress caused by lift Variation, to prevent the failure logging of mistake.Detection window is established to determine whether valvetrain system has expected amount of deflection.Example Such as, valve-closing than expected more sharply will cause camshaft angle to be earlier closed, thus cross rapid rate due to unexpected and Valve is caused to rebound.Tolerance around detection window and main outline can detecte these exceptions.

5.2.4 durability test plan

Fault mode and consequences analysis (DFMEA) are designed to determine SRFF fault mode.Equally, system-level and sub System-level determining mechanism.The information is used to develop and assess the durability of SRFF in different operational situations.By test type point For four classes as shown in Figure 65, comprising: service check, subsystem testing, extreme limit test and acceleration system aging.

The framework of Key experiments for durability is shown in Figure 65.Service check test is examined according to application requirement The performance of SRFF and be durability examine the first step in.Subsystems test assessed specific function and in the product life cycle Wear interface.Extreme limit test makes SRFF undergo harsh use and operating limit.Finally, accelerated aging test is complete Assess to face the comprehensive test of SRFF.The success of these tests demonstrates the durability of SRFF.

Service check

Tired & rigidity

Cycling test is carried out to SRFF to ensure fatigue life with significant design margin more than application load.Valve Mechanism performance depends greatly on the rigidity of the component of a system.Measurement rocker arm rigidity designs and ensures acceptable to verify Dynamic property.

Valve mechanism dynamic property

The description of valve mechanism Dynamic performance examination and performance illustrate in result chapters and sections.The test includes answering SRFF Become measurement and measurement valve-closing rate.

Subsystem testing

Convert durability

Conversion durability test is turned by making SRFF in locking, unlocking and return to lock state total 3,000,000 times to assess Change planes structure (Figure 24 and 25).The main purpose of the test is assessment locking mechanism.Since test cycle is 50% under low lift And obtain additional durability information related with torque spring.

Torque spring durability and fatigue

Torque spring is the integral member for converting roller finger follower.Torque spring allows outer arm to operate in lost motion, It keeps contacting with high-lift cam axis peach tip simultaneously.Torque spring durability test is executed to assess torque spring in operational load Under durability.Torque spring durability test is carried out using the torque spring being mounted in SRFF.Torque spring fatigue test Torque spring fatigue life is assessed under the stress level of raising.The torsion in end-of-life less than 15% will be successfully defined as Spring-load loss.

Idling durability

The limit lubricating status as caused by low oil pressure and high oil temperature is simulated in idling durability test.The test is used to assess Abrasion between slide block pad and bearing, between valve tip and head portion that and ball-and-socket and bulb stopper.Lift condition in high lift or Piercing test is kept constant under low lift.Overall mechanical gap is measured when inspecting periodically, and it is the primary metric of abrasion.

Extreme limit test

Hypervelocity

Conversion rocker arm fault mode includes the loss of lift condition control.SRFF be designed under low lift mode with The maximum speed of crankshaft of 3500rpm operates.SRFF includes protecting in the case where unexpected failure to the design of these higher rotation speeds Shield, so as to cause low lift mode.Low lift fatigue life test is executed at 5000rpm.For high lift and low lift two Kind state executes engine flare test at 7500rpm.

Cold start durability

Cold start durability test is subjected to the energy that 300 engine starts recycle from -30 DEG C of initial temperature assessment DLC Power.In general, cold climate engine start at these tem-peratures will include cylinder heater.Select the extreme test To show reliability and be repeated 300 times on the engine mount of motorization.Test measurement DLC coatings withstood is due to low The ability of the lubrication of reduction caused by temperature.

Critical transitions durability

SRFF is designed to convert on the basic circle of camshaft when latch pin is not contacted with outer arm.In incorrect OCV Timing or lower than all the minimum control channel oil pressure of requirement of journey are sold in the case where, pin starts possibility in next lift events Still in movement.The incorrect position of latch pin may cause the part between latch pin and outer arm and engage.In outer arm and lock bolt In the case where part engagement between pin, outer arm may slide from latch pin, so as to cause roller bearing and low lift cams axis Impact between peach tip.Critical transitions durability is to form quantization reliability and the not expected condition in the service life of vehicle Abuse test.Critical transitions test makes SRFF be subjected to 5000 subcritical transition events.

Accelerate bearing durability

Accelerating bearing durability is the life test for assessing the service life for the bearing for completing critical transitions test.The examination Test whether the consequence for determining critical transfer test can shorten the service life of roller bearing.The examination is run with the radial load of increase It tests to reduce the deadline.New bearing is tested simultaneously to examine the performance and abrasion of the bearing for being subjected to critical transitions test.Run through The test carries out vibration measurement and is analyzed to detect the beginning of damage of the bearing.

Used oil test

Acceleration system degradation and idling durability test are executed using the used oil with 20/19/16 sensitivity Profile.The oil is obtained from engine when changing oil.

Acceleration system aging

Acceleration system degradation is used to assess including sliding interface, locking mechanism and the low liter between camshaft and SRFF The overall durability of the rocker arm of journey bearing.Mechanical clearance is measured when inspecting periodically, and it is the primary metric of abrasion.Figure 66 The test protocols that assessment SRFF is recycled to acceleration system degradation cyclic test are shown.Mechanical clearance measurement and FTIR measurement are permitted Permitted to check respectively for the general health of SRFF and DLC coating.Finally, carrying out disassembly processing to components to understand from experiment opening The source of any variation for the mechanical clearance that begun.

Figure 67 is the pie chart of the opposite testing time for the SRFF durability test for showing that total hourage is about 15,700.Add Speed system degradation due to accelerator coefficient and combination load and every test hour provides to SRFF in primary test and at most believes Breath, thus the total testing time of distribution 37%.Idling durability (slow-speed of revolution, low lift and the slow-speed of revolution, high lift) test due to The duration tested every time is long and occupies the 29% of total testing time.Durability is converted for multiple life test and is constituted total The 9% of test period.The difficulty and cold start of critical conversion durability and cold start durability test due to realizing critical transitions Thermal cycle times needed for durability and need the plenty of time.Data are carried out in terms of the total time needed for carrying out these modes Quantization, rather than just critical transitions and cold start time itself.The remainder of subsystem and extreme marginal test need total The 11% of test period.

Valve mechanism dynamic property

Valve mechanism dynamic property shows the performance and durability for determining engine.By assessment valve in its return gas Shutdown rate and rebound when gate seat determine dynamic property.Strain measurement is in the engine speed envelope about camshaft angle On provide information related with the load of system.Strain measurement is carried out to inner arm and outer arm in homogeneous state of stress position.Figure 68 shows The deformeter being mounted on SRFF out.Outer arm and inner arm are answered equipped with instrument with the purpose measurement based on the load on verifying SRFF Become.

Valve mechanism Dynamic performance examination is carried out to assess the performance of valve mechanism.In the name of with limit overall mechanical gap width Execute the test.Provide nominal situation.The revolving speed scanning from 1000 to 7500rpm is executed, thus in each engine speed Record 30 valve events.The post-processing of dynamic performance data allows to calculate valve-closing rate and valve rebound.It is mounted on Deformeter on the inner arm and outer arm of SRFF indicates the abundant load in whole engine speed lower shake-changing arms, to prevent air-stop gate mechanism " pumping (pump-up) " of separation or HLA between component.Pumping HLA compensation valve rebound or valve mechanism amount of deflection to Make valve when staying open on camshaft basic circle.Minimum, maximum and average closing velocity is shown to start to understand Distribution in the machine range of speeds.High lift shutdown rate is presented in Figure 67.The shutdown rate of high lift meets design object.Value Span about 250mm/s is differed between minimum speed and highest 7500rpm while being safely retained in target.

Figure 69 shows the shutdown rate of low lift cams axis profile.Usually 3500rpm at most occurs for operation, wherein closing speed Rate is maintained at 200mm/s hereinafter, the shutdown rate is safely in the design margin of low lift.The system is designed to low The hypervelocity condition of 5000rpm under lift mode, wherein maximum shutdown rate is lower than the limit.Valve-closing rated design target is full Sufficient high lift and low lift both of which.

Critical transitions

Critical transitions test is executed by the way that latch pin is maintained at the critical point engaged with outer arm as shown in figure 27.Lock bolt Be partially joined on outer arm, this provide outer arm separated with latch pin and the chance of the control that causes moment to lose to rocker arm. The bearing of inner arm is compressed against in low lift cams axis peach tip.Far more than in order to show the reliability of service life of SRFF and to vehicle The quantity of the number of expected critical transitions tests SRFF.The abrasion of locking mechanism during critical transitions test assessment lock bolt separates And durability of the bearing to the impact occurred during critical transitions.

It is tested using critical transitions are executed with the engine of similar motor drive shown in Figure 63.About critical pressure tune Whole clearance adjuster control channel.Engine is changed with constant rotational speed operating and pressure in critical pressure or so to adapt to system Lag.Critical transitions are defined as greater than the valve decline of 1.0mm.The valve falling head of typical SRFF, which is distributed in Figure 70, to be shown Out.It should be noted that occur within 1.0mm more than 1000 subcritical transformations, they are by list display but not towards having tested At counting.Figure 71 illustrates distribution of the critical transitions about camshaft angle.Maximum accumulation occurs and then be more than peak lift Later, rest part is substantially evenly distributed.

Through the abrasion of test monitoring locking mechanism and bearing.By the typical wear of outer arm (Figure 73) and new components (Figure 72) is compared.After critical transitions needed for completing, check whether rocker arm correct operation and draws a conclusion to test.Institute The edge abrasion shown has not significant impact lock function and overall mechanical gap, because most of lock bolt main body shows can be ignored The abrasion disregarded.

Subsystem

The wear interface of subsystems test assessment specific function and SRFF rocker arm.Switching reliability assesses the expection in SRFF The function and abrasion of locking mechanism in service life.Similarly, idling durability makes bearing and slide block pad undergoes worst-case state, packet Include low lubrication and 130 DEG C of oil temperature.The examination of torque spring durability is completed by making torque spring undergo about 25,000,000 circulations It tests.Through the test measurement torque spring load to measure deterioration.Pass through what is lost in the maximum planned load no more than 15% Test is set to extend to 100,000,000 circulations to obtain more confidence simultaneously.Figure 74 show on-test and at the end of outer arm on Torque spring load.After 100,000,000 circulations, there are the Smaller load loss that size is 5% to 10%, connecing lower than 15% By target and show that outer arm is directed to the abundant load of four engine lives.

Acceleration system aging

Acceleration system degradation is used as comprehensive durability test of the evaluation to duration performance.The test represents harshness Terminal user accumulated damage.The constant rotational speed and acceleration profile of test cycle average out to about 5000rpm.By each circulation Time decomposition it is as follows: 28% stable state and recycles 15% low lift between high lift and low lift, and rest part is adding Under fast state.Test result shows that the variation of the gap in the test in a service life accounts for the 21% of the available abrasion specification of rocker arm.By The acceleration system degradation of 8 SRFF composition is extended to the worn out mode for being above standard the service life to determine SRFF.Once super Standard duration is crossed, just often records overall mechanical gap measurement in 100 test cycles.

Acceleration system aging measurement result provides in Figure 75, and Figure 75 shows that wear specification is exceeded 3.6 service life.After It is continuous to test and realize 6 service life fault-frees.Test is extended to multiple service life display once being more than that initial break in period is mechanical Linear change just occurs for gap.The dynamic of system shows the overall mechanical gap due to increase and deteriorates；But, working performance is 6 Secondary engine life remains intact.

5.2.5 durability test result

What execution illustrated in test plan respectively tests and provides the conclusion of result.Show valve dynamic property, critical Change the result of durability, torque spring durability and final acceleration system degradation.

Make SRFF experience accelerated aging test and special function test to prove reliability and conclude in table 3.

Table 3: durability is summarized

Adding up to the engine life requirement for being equivalent to 200,000 miles --- it is more than mandatory requirement that it, which is provided, 150,000 miles of very big surplus --- aspect assesses durability.The target of the project is to prove total Test to show at least one Secondary engine life.Main durability test is presented at least acceleration system of 6 engine lives or 1,200,000 miles of durability System degradation.The test also is carried out using used oil, thus reliability of the display to an engine life.Key operation Mode is the conversion operation between high lift and low lift.It converts durability test and at least engine life or 600 three times is presented, 000 mile.Equally, torque spring is reliable for 000 mile at least four engine lives or 800.Remaining is to facing Boundary's transformation, hypervelocity, cold start, the test of bearing reliability and idling mode show engine life at least once.DLC coating It is all reliable for all conditions, it is shown that wear minimum polishing, as shown in Figure 76.As a result, testing with extending SRFF shows the reliability considerably beyond 200,000 miles of service life.

5.2.6 Durability Experiment Conclusion

DVVL system including SRFF, DFHLA and OCV is proved at least 200,000 miles --- this is to be more than 150,000 miles compulsory execution requirement safe clearance --- for be reliable.Durability test is at least No. 6 engines Service life or 1,200,000 miles confirm acceleration system aging.The SRFF is also proved to be for the oil of used oil and aeration It is reliable.The conversion function of SRFF is proved for for engine life or 600,000 miles being three times at least reliable. All subsystems tests show that the reliability of SRFF is more than 200,000 miles of an engine life.

Critical transitions testing and verification reliability of engine life to 5000 events or at least once.The condition occurs Oil pressure state except usual opereating specification and as outer arm slides so that SRFF transits to inner arm and causes from lock bolt Severe event.Even if inclement condition, SRFF is also proved to be reliable to such condition.Occur the event in continuous production can Energy property is low.Test result shows that SRFF is reliable for the condition in the case where critical transitions occur.

It is 7300rpm for maximum engine speed that the SRFF, which is proved to, and outburst speed conditions are the riding of 7500rpm It is reliable for vehicle application.The engine test of operating has one compared with the engine test of non-operating described herein The wear patterns of cause.It is all reliable that DLC coating in outer arm slide block pad, which is proved to be under all operating conditions,.As a result, going out In inhaling the purpose that loss improves fuel economy via the pump of reduction in the operating of sub-load engine, SRFF design is suitble to In four cylinder passenger car applications.The technology can extend to the other application including six cylinder engine.The SRFF, which is proved to be, to be permitted How far be more than automotive needs situation in be reliable.It is contemplated that in addition exploitation diesel applications are to solve increased engine Load, oily pollution and life requirements.

5.3 slide block pads/DLC coating abrasion

5.3.1 wear test plan

This section describes the test plans of the wear-resisting property and durability that are used to examine the DLC coating in outer arm slide block pad. Target is the durability how relationship established between design specification and processing parameter and each influence slide block pad interface.The cunning Three key elements in arena face are as follows: camshaft peach tip, slide block pad and valve mechanism load.Each element have need by comprising The factor of the influence to the durability of DLC coating is determined in test plan.Each component is described in detail as follows:

Camshaft-high-lift cam axis peach tip width is designated as ensuring slide block pad during engine operating at holding In in camshaft peach tip.This includes the axial position variation of change in size that is thermally grown or being attributed to manufacture.As a result, slide block pad Full width can be contacted with camshaft peach tip may be not present the risk that camshaft peach tip deviates slide block pad.With valve lift properties The shape of related peach tip (profile) has also determined in the exploitation of camshaft and SRFF.This, which is generated, needs to apply relative to DLC Two factors that the durability of layer is understood: first factor is peach tip material, and second factor is camshaft peach tip Surface smoothness.The test plan includes with the different surfaces state verification cast iron and cast steel camshaft peach tip in peach tip.First Surface state includes preparing camshaft peach tip ((as-ground) when grinding) by grinding operation.Second surface state is to throw The surface smoothness state of peach tip is improved after light operation (after polishing).

Slide block pad-slide block pad profile is directed to the specific requirement to valve stroke and valve mechanism dynamic property and designs.Figure 77 It is the graphical representation of the contact relation between the slide block pad on SRFF and the high lift peach tip pair of contact.Since expected manufacture becomes Different, there are angle alignment relationships in the contact surface, and the ratio exaggerated in Figure 77 exemplifies.Crown surface is due to various alignment shapes State and the risk for reducing the edge load of slide block pad.However, crown surface increases manufacture complexity, therefore to test plan Influence of the coronal to the interface performance of coating is increased to determine its necessity.

Figure 77 shows the coronal option on the camshaft surface by the method for selection.It will be based on expected load and coronal The hertz stress of variation is calculated for the guidance in the test plan.Alignment tolerances (angle) between two pads need to combine pre- The coronal of phase changes to provide.The desired output of the test is how the different slide block pad degree of registration of practical understanding influences DLC coating.The target value of 0.2 degree of dislocation is provided using Stress calculation.These calculating are used only as datum mark.The test plan It joined three values for the angle between slide block pad: < 0.05 degree, 0.2 degree and 0.4 degree.Angle is lower than zero of 0.05 degree Part is considered being flat, and the components that angle is 0.4 degree represent the double of calculated datum mark.

The second factor for needing to assess in slide block pad is surface smoothness of the slide block pad before DLC coating.Slide block pad Manufacturing procedure includes the grinding operation to form the profile of slide block pad and the polishing process for preparing the surface for DLC coating.Each work Sequence influences final surface smoothness of the slide block pad before applying DLC coating.The test plan combines the effect of each process simultaneously And provide result for establishing in technique the final specification for grinding specification and the surface smoothness after polishing process.It should Surface smoothness when test plan combines grinding and after polishing.

The last element of valve mechanism load-is to load slide block pad by the operation of valve mechanism.Calculating is provided gas Door machine structure load transition is the mode of stress level.The durability of both camshaft peach tip and DLC coating is based on each and is failing The stress level that can be resistant to before.Camshaft peach tip material should be defined in 800-1000MPa's (moving contact stress) In range.The range is considered as nominal design stress.For accelerated test, the stress level in the test plan is set at 900-1000MPa and 1125-1250MPa.These values respectively represent the top half and design stress of nominal design stress 125%.

The test plan combines six factors to examine the durability of the DLC coating in slide block pad.(1) camshaft peach tip Material, the form of (2) camshaft peach tip, the surface state of (3) camshaft peach tip, the angle pair of (4) slide block pad and camshaft peach tip Together, the surface smoothness of (5) slide block pad, and the stress that (6) are applied to the slide block pad of coating by opening valve.In this section The element of general introduction and the conclusion of factor are shown in table 1.

Table 1: test plan element and factor

5.3.2 component wear test result

Test target is to determine each factor to the relative contribution of the durability of slide block pad DLC coating.Most of test configuration Including minimum two factors in the test plan.Slide block pad 752 is mounted on test piece 751 shown in Figure 78 In support arm 753.All configurations are tested under two stress levels to allow each factor relatively.Inspection intervals are being surveyed Interval is increased to 300- when runin is begun in the range of 20-50 hours and as the time spent by observation result is longer 500 hours.It is presented when template and pause test when significant changes occurs in the loss of DLC coating or the surface of camshaft peach tip.? Stress level higher than application requirement is tested, to accelerate the effect of the factor.As a result, the engine life is commented Estimate for conservative estimation and be used to the relative efficacy for the factor that proving institute is tested.The sample in a service life is completed on testing stand is It meets the requirements.Sample more than the service life three times without DLC loss is considered excellent.Test result is separated into two sections to have Conducive to explanation.First segment illustrate cast iron cam shaft as a result, and the second section check steel camshaft result.

The test result of cast iron cam shaft

First test is using cast iron cam shaft peach tip and compares slide block pad surface smoothness and two kinds of angle alignment configurations.Knot Fruit is as shown in table 2 below.The table summarizes the combination of slide block pad angle and the surface state tested using cast iron cam shaft.Most Big design and 125% maximum planned load state verification are respectively combined.Listed value represents each hair for combining and realizing dduring test The number in motivation service life.

Table 2: cast iron test matrix and result

Camshaft is by testing the cracking for all having occurred and test being caused to terminate.It is most of before engine life half It cracks.Cracking is more serious on the higher components of load, but exists on maximum planned load components.Analysis is taken off The ability that two kinds of loads are above camshaft is shown.Cast iron cam shaft peach tip, which is commonly used in having, includes similar load level In the application of rolling element；However, the material is not suitably to select in the sliding interface.

Inspection intervals are enough frequently to study influence of the surface smoothness to Coating Durability.Any surface finish with grinding The template of degree is in testing very early by DLC coating loss.Template shown in Figure 79 A is shown occurs DLC ahead of time in testing The sample of coating loss.

Scanning electron microscope (SEM) analysis discloses the breaking property of DLC coating.Metal surface below DLC coating Adequately bearing will not be provided to coating.The coating metal much harder more in connection than it；Therefore, if underlying metal is significant Deformation, then therefore DLC may be broken.The template being polished before coating camshaft peach tip start cracking before performance compared with It is good.The optimum of cast iron cam shaft be under maximum planned load it is flat, polishing after template combination 0.75 service life.

The test result of steel camshaft

Next battery of tests combines steel peach tip camshaft.Test combinations and being summarized in table 3 for result are listed.Make Test camshaft peach tip with four kinds of various configurations: (1) surface smoothness of the flat peach tip in grinding, (2) coronal peach tip are being ground Surface smoothness when mill, after a polish, and nominal coronal in (4) peach tip is polishing the coronal peach tip of (3) bottom line Afterwards.Slide block pad on template is polished before DLC coating and with three angle measurement: (1) flat (folder less than 0.05 degree Angle), (2) 0.2 degree of angle, and (3) 0.4 degree of angle.The load of all camshafts is set to the maximum design or maximum is set The 125% of meter level.

Table 3: steel camshaft test matrix and result

The test specimen for combining the flat steel camshaft peach tip and 0.4 degree of angle template when grinding is negative in 125% design Service life no more than once under lotus level.The sample tested under design maximum stress continues a service life, but the influence to coating It is identical.0.2 degree performs better than with flat sample, but is no more than the service life twice.

The template and flat template for the use of grinding, flat steel camshaft peach tip and angle being 0.2 degree carry out the test. Time needed for before observing coating loss on 0.2 degree of sample is 1.6 service life.The time of flat template operation is slightly longer, real 1.8 service life are showed.The pattern of DLC loss in flat sample is uneven, and wherein maximum loss is located at the outside of contact surface.It connects Coating loss on the outside of contacting surface indicates that the stress that slide block pad is subjected to is uneven on its width.The phenomenon is known as " edge effect It answers ".The solution for reducing the stress of the edge of the element of two alignment is to increase coronal contour to one of element.Benefit Have with the application of SRFF to the increased coronal contour of camshaft.

Next battery of tests combines minimum coronal value and 0.4 degree, 0.2 degree and flat polishing slide block pad.It should Organize the positive result that testing and verification increases camshaft bizet.The improvement of 125% peak load is for 0.4 degree of sample 0.75 to 1.3 service life.For same load, the smaller improvement in from 1.8 to 2.2 service life is presented in flat components.

Last battery of tests includes the steel cam after all template of three angles and the polishing that in the name of coronal value is processed Axis peach tip.Most apparent difference is the friendship between camshaft bizet and slide block pad and the angle alignment of camshaft peach tip in these results Mutually.Flat sample and 0.2 degree of sample are more than service life three times in two kinds of load levels.0.4 degree of sample is no more than the service life twice.Figure 79B shows the typical case of one of breadboard tested with 0.2 degree of angle in maximum planned load.

These results prove the following contents: (1) nominal value of camshaft coronal effectively will be up to 0.2 degree of slide block pad Angle alignment mitigates to flat；(2) mitigation is effective in the maximum planned load of intended application and 125% maximum planned load； (3) polishing camshaft peach tip is facilitating the resistance to of DLC coating when slide block pad polishing and camshaft peach tip coronal combine Long property.

Each test result helps to more fully understand influence of the stress to the durability of DLC coating.As a result show in Figure 80 Out.

It is no more than engine life in sliding interface under Design cooling load using the early test of cast iron cam shaft peach tip Half.It is next to improve in identifying in the form of " edge effect ".To after polishing camshaft peach tip increase coronal and By Coating Durability is increased to exceed the service life three times to being best understood from for angle alignment of permission.As a result the test result to observe With the design margin of the demonstration between the design maximum stress of the application under the engine life estimated each time.

Mistake of coated sample of influence of the surface smoothness to DLC durability when from grinding to coating template when polishing It is the most obvious in crossing.The slide block pad tested when grinding and after coating is no more than one third time engine life as shown in Figure 81. The slide block pad of the bigger bearing capacity and coating for the substrate of the surface smoothness of slide block pad provided below coating The overall durability of raising.

The test result of cast iron and steel camshaft provides: (1) specification of slide block pad and the angle alignment of camshaft, (2) angle It is aligned the specification clear evidence compatible with camshaft peach tip bizet specification, (3) DLC coating is will be more than under maximum planned load It is remained intact in camshaft peach tip coronal and the design specification of slide block pad alignment, (4) need after the grinding of slide block pad Polishing operation is wanted, specification in the technique of (5) grinding operation, the specification of (6) surface smoothness of slide block pad before coating, and (7) facilitate the durability of the DLC coating in slide block pad to the polishing operation of steel camshaft peach tip.

5.4 slide block pad fabrication schemes

5.4.1 slide block pad fabrication scheme describes

Outer arm utilizes the casting processed.The angle that slide block pad before coating has been established in the prototype components processed from billet is inclined The target of difference and surface smoothness.Manufacture grinding and the execution of polishing process occur simultaneously with test, and are shown in FIG. 2. Test result provides the return and guidance in execution of the manufacturing process of outer arm slide block pad.It is adjusted in technique based on test result Parameter and the new sample that processing is then assessed in test fixtures.

This section describes the manufacturing processes of slide block pad to be evolved into the outer arm of SRFL from template.

The first step for executing manufacture grinding technics is assessment different machines.Test run is carried out on three different abrasive machines Row.Every machine all utilizes identical ceramic cubic boron nitride (CBN) grinding wheel and corrector.Selection CBN grinding wheel is because it is mentioned For: (1) consistency between components is improved, (2) improve the precision in the application for requiring tighter tolerances, and (3) pass through More fragments are generated between amendment circulation compared with aluminium oxide and improve efficiency.Every machine utilizes identical feed speed Grind a collection of template, and every time by when remove identical quantity of material.Provided with fixed device, to allow template sequentially Grinding.Template is tested, because sample has been polished and has been tested on abrasion platform.This method provides pass through to protect Hold the consistent fair manner to assess abrasive machine of the parameters such as fixed device, grinding wheel and trimmer.

It is measured after collecting each group of sample.Sliding block is carried out using 654 coordinate measuring machine of Leitz PMM (CMM) The angular measurement of pad.Surface finish measurement is carried out on 120 talysurf of Mahr LD.Figure 83, which is shown, different grinds three Grinding machine shows rocker piece angle control result.Result above line is that there is a situation where the obvious deteriorations of coating performance.Target Region indicates that the components for testing the angle do not show difference in life test.Two in abrasive machine are unable to satisfy template On slide block pad angle target.In contrast, third platform abrasive machine works well.The test result of abrasion platform confirmed to slide Interface is sensitive to the angle for being higher than the target.The combination of the abrasive machine experiment and test that illustrate in previous section facilitates manufacturing equipment Selection.

Figure 84 is summarized with the Surface finish measurement with the template of identical angle data shown in Figure 83.For sliding block The surface smoothness specification of pad is established due to these test results.There is reduction higher than the surface finish of shown limit line Durability.

Identical two abrasive machines (A and B) are also unable to satisfy the target of surface smoothness.The target of surface smoothness is based on The net change of surface smoothness in the polishing process of given a collection of components and establish.It is exactly to peel off since grinding technics The template of body (outlier) keeps the body that peels off after polishing process；Therefore, control grinding operation when surface smoothness for It is critically important for the slide block pad of final surface smoothness before satisfaction coating can be generated after polishing.

From every hardware check measurement result.Both abrasive machine A and B have the change in each pulvilliform formula in angular measurement Change.As a result mean that grinding wheel is vertically moved in its lapping sliders pad.The movement of vertical grinding wheel and the machine of such abrasive machine Global stiffness is related.Machine stiffness can also influence the surface smoothness for the components being ground.By passing through test fixtures The slide block pad of the specification grinding outer arm of verifying requires the rigidity determined in abrasive machine C.

The experience obtained from grinding template is applied to the exploitation of the fixation device of the outer arm of grinding SRFF.However, outer arm Provide visibly different one group of challenge.Outer arm is designed at it be hard on direction that camshaft peach tip operates.Outside Arm is on the direction of slide block pad width without so hard.

Grinding fixed device needs (1) to make each slide block pad vibration damping in the case where no-bias, and (2) rigidly support each sliding block Pad is to resist the power applied by grinding, and (3) reliably repeat the step in mass production.

The exploitation of the fixed device of outer arm is since hand-operated clamping formula block.Each remodeling of fixed device is attempted from damper mechanism It eliminates bias and reduces the deviation of abradant surface.Figure 85 shows the fixation device by keeping outer arm during slide block pad grinding operation Design development obtain result.

It is that surface finish quality sets key SRFF outer arm slide block pad specification by the scheme that the test plan is completed Boundary simultaneously forms tolerance in terms of angle.Research grinding operation surface smoothness is to the final surface smoothness obtained after polishing Influence and it be used to establish be used for the specification of intermediate treatment standard.These parameters, which will be used to establish guarantee, to be produced in high yield The middle equipment for maintaining coating performance and the fixed device scheme of components.

5.4.2 slide block pad fabrication scheme

Conclusion

The DLC coating being constructed of in SRFF slide block pad in the DVVL system for including DFHLA and OCV component is proved to be Reliability and the far super passenger car life requirements of durability.Although DLC coating has been used in multiple industries, it is in automobile air valve The production in mechanism market is limited.Surface smoothness, DLC stress level and the manufacture that factory is determining and quantization is before DLC coating The influence of the technique of slide block pad.The technology is proved to be the continuous production for being suitble to and preparing SRFF slide block pad.

Surface smoothness through life test for maintaining the DLC coating in slide block pad very crucial.Test result show when Premature failure occurs when surface smoothness is too coarse.It is highlighted herein far more than any surface finish of the life cycle test requirements to Ole Spend horizontal system.The program maintains the DLC at the top of chromium nitride base intact, so that the underlying metal of SRFF will not With camshaft peach tip material.

Also determine and confirm the stress level in DLC slide block pad.Test highlights the angle control to the edge of slide block pad Demand.Confirm the increased bizet of camshaft peach tip increases the edge load effect for being attributed to manufacturing tolerance it is very big Reliability.Test result more than service life life requirement is presented to the specification of angle control setting.

It has also been found that camshaft peach tip material is a key factor in sliding interface.To the DVVL system based on SRFF Encapsulation requires the reliable solution for being required to withstand up to the sliding contact stress of 1000MPa.For these stress levels Under solution for, need high-quality steel to avoid will affect the service life of sliding interface camshaft peach tip cracking.Hair Final system after now handling and polish with steel camshaft material, coronalization is more than service life life requirement.

The technique for illustrating to produce slide block pad and DLC in high volume manufacturing processes.Crucial fabrication scheme concentrates grinding to set Alternative and grinding wheel machine grinding wheel and for production slide block pad grinding technics keep SRFF outer arm fixation device on.Selected system It makes technique and presents the reliability for meeting the specification for ensuring durable sliding interface through the service life of engine.

DLC coating in slide block pad, which is proved to be, is more than and the consistent life requirements of system DVVL result.Outer arm slide block pad On DLC coating to be proved to be under all operating conditions be all reliable.As a result, in the operating of sub-load engine The purpose that loss improves fuel economy is inhaled via the pump of reduction, SRFF design is suitable for four cylinder passenger car applications.For The sliding interface for being coated with DLC of DVVL is proved to be durable and VVA technology is made to can be used in various engine air valve devices In.

II. single peach tip cylinder deactivation system (CDA-1L) system embodiment description

1. CDA-1L system survey

CDA-1L (Figure 88) is mounted in the compact actuated by cams on the internal combustion engine of piston driving and utilizes double-fed Single peach tip cylinder that formula hydraulic lash adjuster (DFHLA) 110 and oil control valve (OCV) 822 operate is closed down (CDA-1L) conversion Rocker arm 1100.

Now, with reference to Figure 11,88,99 and 100, CDA-1L layout includes four main members: oil control valve (OCV) 822, Double-fed type hydraulic lash adjuster (DFHLA), CDA-1L conversion rocker arm assembly (also referred to as SRFF-1L) 1100, single peach tip cam 1320.Default configuration is in usual lift (locking) position, wherein 1102 quilt of the inner arm 1108 of CDA-1L rocker arm 1100 and outer arm It locks together, just looks like the same in standard valve mechanism to cause engine valve to open and allow cylinder operation. There are two oily ports for the tool of DFHLA 110.Lower oil port 512 provides backlash compensation and by feeding engine oil, with standard HLA phase Seemingly.The port 506 that oils of referred to as switching to pressure port provides the lock bolt in controlled oil pressure and SRFF-1L from OCV 822 Pipeline between 1202.It is, as noted, inner arm 1108 and outer arm 1102 in SRFF-1L 1110 are just when lock bolt is engaged It is worked together as standard rocker arm to open engine valve.In no lift (unlatched) position, inner arm 1108 and outer arm 1102 can independently move to realize that cylinder is closed down.

As shown in Figure 88 and 99, a pair of of lost motion torque spring 1124 be added into so that the position of inner arm 1108 to be biased into so that It always maintains to continuously contact with camshaft peach tip 1320.Lost motion torque spring 1124 needs the design than using multiple peach tips High preset load, to be conducive to continuously contacting between camshaft peach tip 1320 and inner arm roller bearing 1116.

Figure 89 shows inner arm 1108 in SRFF-1L 1100 and outer arm 1102 and 1202 mechanism of lock bolt and roller axle Hold 1116 detail drawing.Compared with the configuration with more than one peach tip, the function that SRFF-1L 1100 is designed remains similar The complexity of camshaft 1300 is encapsulated and reduces, for example, the individual no lift for each position SRFF can be eliminated Peach tip.

It as shown in Figure 91, include an OCV 822, for arranging for the complete CDA system 1400 of a cylinder Two SRFF-1L rocker arms 1100 of gas, for two SRFF-1L rocker arms of air inlet, for one of each SRFF-1L 1100 DFHLA 110 and the single peach tip camshaft 1300 for driving each SRFF-1L1100.In addition, 1400 system of CDA is designed so that SRFF-1L1100 and DFHLA 110 is identical for air inlet and exhaust the two.The layout allows single OCV822 to convert simultaneously Each of four 1100 components of SRFF-1L rocker arm that cylinder is closed down required.Finally, the system is 822 from ECU 825 to OCV It is electronically controllable in usual lift mode and without being converted between lift mode.

It is shown in Figure 90 using the distribution engine for an exhaust valve and an inlet valve of SRFF-1L 1100. The encapsulation of SRFF-1L 1100 is similar to standard valve mechanism.Cylinder head needs to modify to provide from lower channel 805 to OCV 822 Oil supply (Figure 88,91).Furthermore, it is necessary to second (on) oil duct 802 connects the conversion port 506 of OCV 822 and DFHLA 110 It connects.Engine cylinder cap architecture keeps identical, so that 110 center of valve center line, camshaft centerline and DFHLA Line is consistent.Since this three center lines are maintained relative to standard valve mechanism, and since SRFF-1L 1100 is kept It is compact, so cylinder head height, length and width keep almost unchanged compared with standard valvetrain system.

2.CDA-1L system improving technology

For several technologies in the system in different application, they to be described as DVVL disclosed herein in the text The component of system.These components include:

2.1. oil control valve (OCV)

As described in chapters and sections in front, and shown in Figure 88,91,92 and 93, oil control valve (OCV) 822 is to draw It leads or does not guide the hydraulic fluid after pressurization to cause rocker arm 1100 in usual lift mode and without converting between lift mode Control device.PCV is for example intelligently controlled using the control signal sent by ECU 825.

2.2. double-fed type hydraulic lash adjuster (DFHLA)

In the presence of many for maintaining the hydraulic lash regulating device in the gap in engine.Carry out rocker arm 100 (Fig. 4) DVVL conversion needs conventional gap management, but tradition HLA device is not enough to provide the required oil stream amount requirement for conversion, The relevant side loaded applied by component 100 is born during operation, and is assemblied in limited encapsulated space.It describes and turns The compact double-fed type hydraulic lash adjuster 110 (DFHLA) that rocker arm 100 is used together is changed, is had features designed to low consumption One group of parameter of optimal oil stream dynamic pressure is provided and geometry and is designed to management one group of parameter of side loaded and several What shape.

As shown in Figure 10, the cooperation of bulb stopper end 601 is in the ball-and-socket 502 for allowing moving in rotation freedom degree in any direction In.This allows bulb stopper end 601 within a particular mode of operation --- for example low lift is being transformed into from high lift and from low lift When being transformed into high lift --- side and possibly asymmetric load.With the typical bulb stopper end for HLA device on the contrary, The 110 bulb stopper end 601 DFHLA is made of thicker material to prevent side loaded, is shown in Figure 11 as plug thickness 510.

The material selected for bulb stopper end 601 with higher can also allow motion stress load, such as chrome alum alloy.

Flow of pressurized path in DFHLA 110 be designed to high flow capacity and low pressure drop with ensure consistent hydraulic conversion and Reduced pumping loss.DFHLA is mounted on really to be sized to lean against within the engine and seal on outer surface 511 shown in Figure 11 In cylindrical reception seat.The cylindrical reception seat combines with the first oil flow passage 504 and forms the envelope with regulation sectional area Close fluid path.

As shown in figure 11, the preferred embodiment includes four oily flowing ports 506 (only showing two) because they with etc. It is arranged in away from the mode separated around the base portion of the first oil flow passage 504.In addition, two the second oil flow passages 508 with etc. It is arranged in around bulb stopper end 601 away from the mode separated, and is in fluid communication through oily port 506 and the first oil flow passage 504.Oil Flowing ports 506 and the first oil flow passage 504 are really sized to particular area and are spaced in around DFHLA 110 with true Protect the uniform oil stream amount and minimum pressure drop from first flow channel 504 to third oil flow passage 509.Third oil flow passage 509 determine size for the combination oil stream from multiple second oil flow passages 508.

2.3. it senses and measures

It can be used to verify translative mode using the information of sensor collection, determine error condition, or provide and be used in combination through analyzing In the information of conversion logic and timing.As can be seen, sensing and measurement described in the chapters and sections before about DVVL system are real Applying example can also be applied to CDA-1L system.Therefore, in DVVL valve position and/or motion sensing and logic can also be used for In CDA system.Similarly, for determining the sensing and logic and for the rocker arm phase of DVVL system of the location/motion of rocker arm The relative position of each other/movement can also be used in CDA system.

2.4. torque spring designs and implements scheme

The torque bigger than conventional existing rocker design is provided and maintains the reliable torque spring of high reliability simultaneously 1124 enable CDA-1L system to maintain correctly operation by all dynamic operation modes.The design of torque spring 1124 and It manufactures and is described in the chapters and sections below.

3. conversion and control and logic

3.1. engine embodiment

CDA-1L embodiment may include any amount of cylinder, such as 6 gas of in-line 4 cylinders and 6 cylinders and V-arrangement configuration Cylinder and 8 cylinders.

3.2. lead to the hydraulic fluid transportation system of rocker arm assembly

As shown in Figure 91, engine of the hydraulic fluid system to the CDA-1L conversion conveying of rocker arm 1100 under controlled pressure Oil.In the arragement construction, the pressure controlled engine oil from cylinder head 801 is not carried out and is fed into via lower oil duct 805 In DFHLA 110.The oil is in fluid communication with the lower port of DFHLA110 512 always, it is used to execute usual hydraulic lash herein It adjusts.It does not carry out pressure controlled being also supplied to oil control valve 822 from the engine oil of cylinder head 801.In controlled pressure The hydraulic fluid from OCV 822 of lower supply is fed into upper oil duct 802.It includes for giving that the conversion of OCV 822, which is directed to, Each of the CDA-1L rocker arm 1100 of CDA deactivation system 1400 of cylinder determine lift mode.It is such as following Described in chapters and sections, the operation of OCV valve 822 is guided by control unit of engine 825 using based on logic below: being sensed and is stored up Specific quantity and the specific oil temperature for the information of specific physical configuration, conversion window and operating condition set, such as cylinder deposited.Come The upper port 506 of DFHLA 110 is directed into from the hydraulic fluid after the adjusting pressure of upper channel 802, it, which is transferred to, herein turns Change rocker arm assembly 1100.Hydraulic fluid is transmitted to 1202 component of latch pin through rocker arm assembly 1100, and it is logical to be used to starting for it herein Normal lift condition and without the conversion between lift condition.

The cleaning air accumulated in upper channel 802 reduces pressure rise time to maintenance hydraulic stiffness and to the maximum extent It is critically important for variation.Pressure rise time directly affect conversion operation during lock bolt traveling time.It is passive shown in Figure 91 The air accumulated to be released to the cylinder below valve cap by the high point that bleeder port 832 is increased in upper channel 802 In lid gap.

3.2.1. it is conveyed for the hydraulic fluid of usual lift mode

Figure 92 shows the SRFF-1L 1100 in the default location that the electric signal for being sent to OCV 822 is not present, and And also show the system and component for realizing the operation under usual lift mode: OCV 822, DFHLA 110, lock pin spring 1204, lock bolt 1202, outer arm 1102, cam 1320, roller bearing 1116, inner arm 1108, valve pad 1140 and engine valve 112.In lower channel 805 do not carry out pressure controlled engine oil and DFHLA 110 backlash compensation (under) port 512 is connected to To realize that standard clearance compensates.OCV 822 adjusts the oil pressure for leading to oil duct 802, then ECU is being not present in upper oil duct 802 To 506 fuel feeding of upper port under 0.2 to 0.4bar when 825 electric signal.The pressure value is lower than compression lock bolt spring 1204 with movement Pressure needed for latch pin 1202.The pressure value is used to keep oil circuit that air may be not present to realize that required system is rung full of oil It answers.The peach tip of cam 1320 is contacted with roller bearing, so that outer arm 1102 be made to rotate around the ball-and-socket of DFHLA 110 to be opened and closed gas Door.When lock bolt 1202 is engaged, SRFF-1L similarly works with standard RFF rocker arm assembly.

3.2.2. for the hydraulic fluid conveying without lift mode

Figure 93 A, 93B and 93C show the detail drawing of the SRFF-1L 1100 during cylinder is closed down during (no lift mode). Control unit of engine (ECU) 825 (Figure 91) provides signal to OCV 822, so that oil pressure is supplied to lock bolt 1202, to cause Make its retraction as shown in Figure 93 b.Lock bolt is set to be fully retracted required pressure in 2bar or more.In the list peach tip CDA embodiment The preset load of higher torque spring 1124 (Figure 88,99) makes camshaft peach tip 1320 be able to maintain the roller axle with inner arm 1108 1116 contacts are held, just look like that this occurs equally in lost motion, and engine valve is remained turned-off as shown in Figure 93 c.

3.3. operating parameters

One key factor of operation CDA system 1400 is usual lift mode to the reliable control between no lift mode System.CDA valve operating system 1400 only can just be converted during scheduled time window between each mode.As described above, from height Conversion of the lift mode to low lift mode and from low lift mode to high lift mode is by coming from control unit of engine (ECU) signal enabling of 825 (Figure 91), conversion of the ECU using the information of analysis storage for example for specific physical configuration Window, the operating condition of storage and the logic by sensor collection treated data.The conversion window duration is by CDA System physical configuration determine, including number of cylinders, by the quantity of the single OCV cylinder controlled, valve lift duration, start The intrinsic lock bolt response time in machine revolving speed and hydraulic control and mechanical system.

3.3.1. the data collected

Real time sensor information includes the input from any amount of sensor, such as the exemplary CDA- shown in Figure 91 Shown in 1L system 1400.As described above, sensor can include: 1) utilize linear variable difference transformer in one embodiment (LVDT) valve stem measured mobile 829,2) utilize hall effect sensor or movement/position 828 of motion detector measurement With latched position 827,3) utilize the DFHLA mobile 826,4 close to switch, hall effect sensor or the measurement of other devices) oil Pressure 830 and 5) oil temperature 890.Camshaft rotation position and speed can be collected directly or be estimated from engine speed sensor.

In in the VVA system of hydraulic operation, oil temperature influences the conversion in the system for such as CDA and VVL etc The rigidity of hydraulic system.If oil supercooling, viscosity slows down change event, so as to cause failure.Relationship needle in Figure 96 Exemplary CDA-1L conversion 1100 system 1400 of rocker arm is shown.In one embodiment using be located at point of use nearby rather than The accurate oil temperature that sensor 890 shown in Figure 91 in engine oil crankcase obtains provides precise information.In one example, Oil temperature in the CDA system 1400 that oil control valve (OCV) 822 is monitored has to be larger than or is equal to 20 DEG C, thus to require Hydraulic stiffness starting is operated without lift (unlock).The commercially available component of any quantity such as thermocouple be can use to be surveyed Amount.The U.S. Patent application US2010/0089347 and in January, 2010 that oil control valve has been announced disclosed on April 15th, 2010 It is described in detail in US2010/0018482 disclosed in 28 days, two applications are incorporated to by being cited in full text herein.

Sensor information is sent to control unit of engine (ECU) 825 as real-time motion parameter.

3.4. the information stored

3.4.1 conversion window algorithm

SRFF requires (close down) from usual lift condition to no lift state and mode conversion on the contrary.It is required that conversion is one A camshaft turn-takes interior generation to ensure correct engine operating.Mode conversion only can be located at the base of cam 1320 in SRFF Shi Fasheng on 1322 (Figure 101) of circle.When lock bolt 1202 (Figure 93) is loaded and moves constrained, valve stroke shape will not occur Conversion between state.Must control be fully engaged with part engage between 1202 transition period of lock bolt in case lock bolt 1202 cunning It is dynamic.Conversion window in conjunction with the electromechanical lock bolt response time intrinsic in CDA system 1400 (Figure 91) determines mode conversion Chance.

The expectation function parameter of CDA system 1400 based on SRFF is set with the V-type conversion roll-type valve lifter at present in production It counts similar.It usual lift and is set to occur during 1322 event of basic circle without the mode conversion between lift and and camshaft 1300 rotation positions are synchronous.SRFF default location is set to usual lift.It is also raw with V-type CDA to the oil stream amount order of SRFF Production system is similar.

Critical conversion is defined as engaging when latching portion, to make valve partly rise and fall back to valve suddenly The unexpected event that may occur when seat.It converts when using camshaft location is synchronous in oil temperature, the regulation parameter of engine speed When period executes conversion command, a possibility that condition, is not high.Critical change event forms the shock loading to DFHLA 110, This may require that the component of a system is facilitated in high-intensitive DFHLA conduct described in chapters and sections in front.

The basic principle of synchronous conversion for CDA system 1400 is shown in Figure 94.Exhaust valve profiles 1450 and air inlet Trolley exterior feature 1452 is indicated according to crank shaft angle.Desired conversion window is defined as the sum of time spent by following operation: 1) 822 valve of OCV supply pressurization oil, 2) hydraulic system pressure overcomes biasing spring 1204 and causes the Mechanical Moving of lock bolt 1202, With 3) from no lift to usual lift and the complete movement of lock bolt 1202 needed for mode on the contrary conversion.In the exhaust valve example In, the conversion window duration 1454 there is from the closing of exhaust valve one, until exhaust valve is again turned on.Lock bolt 1202 exists Keep constrained during exhaust valve lift event.What is be more fully described in chapters and sections below may cause critical conversion 1456 Time window shown in Figure 94.For inlet valve conversion window can relative to inlet valve lift profile similar aspect into Row description.

The preset load of lock bolt

1100 switching mechanism of CDA-1L rocker arm is designed so that hydraulic pressure can apply after lock bolt gap is absorbed To lock bolt 1202, to not cause the variation of function.Design parameter permission passes through upper oil duct during inlet valve lift events OCV 822 in 802 enables hydraulic pressure.Once inlet valve lift profile 1452 returns to 1322 no load condition of basic circle, lock Door bolt just completes it to the specified movement for locking or unlocking mode.The design parameter helps to maximize available conversion window.

The relationship of hydraulic response time and temperature

Figure 96 shows compliance of 1202 response time of lock bolt to the oil temperature for using SAE 5W-30 oil.1202 sound of lock bolt Reflected between seasonable lock bolt 1202 from usual lift (locking) position be moved to no lift (unlock) position and it is on the contrary lasting when Between.For 20 DEG C of the oil temperature and 3bar oil pressure in switching to pressure port 506,1202 response time of lock bolt needs 10 milliseconds.Lock The door bolt response time pressure condition is identical, operation temperature higher (such as 40 DEG C) in the state of foreshorten to 5 milliseconds.When hydraulic response Between be used to determine conversion window.

Variable valve timing

Now, with reference to Figure 94 and 95, some camshaft drive systems are designed to determine phase with bigger than standard drive system Power/motion range relative to crank shaft angle.The technology can be described as variable valve timing, and hold in the determining conversion window allowed It must consider together with engine speed when continuous time 1454.

Being indicated in Figure 95 for valve lift profile is shown according to crank shaft angle, Figure 95 show variable valve timing to turn Change the influence of window duration 1454.Exhaust valve lift profile 1450 and inlet valve lift profile 1452, which show not having, to be drawn The typical recycling for the variable valve timing ability without conversion window 1455 (referring also to Figure 94) of rising.1460 He of exhaust valve lift profile Inlet valve lift profile 1462 shows the typical recycling with the variable valve timing ability for causing no conversion window 1464.It should The example of variable valve timing causes the increase of the duration of no conversion window 1458.Assuming that between exhaust and admission cam shaft 120 crank angle duration variable valve timing ability, the duration converts 1458 at 3500 engine rpm as 6 Millisecond.

Figure 97 be show calculating and measurement temperature and cam determine conversion time caused by the influence of phase variation figure Show.The diagram is based on fixed mutually fixed mutually in Maximum overlap to camshaft in 420 crank angles of minimum overlay 1468 from camshaft Conversion window in the range of 1466 540 crank angles.5 milliseconds of the lock bolt response time shown on the figure is directed to 40-120 DEG C usual engine operating temperature.Hydraulic response variation 1470 is to start to hydraulic pressure from 825 conversion signal of ECU to be enough Measurement before keeping lock bolt 1202 mobile.The research to CDA system 1400 of hydraulic fluid pressure is controlled based on OCV is used, most Big variation is about 10 milliseconds.Hydraulic response variation 1470 considers in the voltage for acting on OCV 822, temperature and engine Oil pressure.Phase position with minimum overlay 1468 provides 20 milliseconds at 3500 engine rpm of available conversion time, and And total lock bolt response time is 15 milliseconds, 5 milliseconds between 1202 response time of time and lock bolt that this representative can be used for converting Nargin.

Figure 98 is also that the temperature for showing calculating and measurement and cam determine the variation of conversion time caused by the influence of phase Diagram.The diagram is based on fixed mutually fixed mutually in maximum weight to camshaft in 420 crank angles of minimum overlay 1468 from camshaft Conversion window in the range of folded 1,466 540 crank angles.10 milliseconds of the lock bolt response time shown in the figure is directed to 20 DEG C cold engine operating temperature.Hydraulic response variation 1470 is to start to hydraulic pressure from 825 conversion signal of ECU to be enough to make It is measured before lock bolt 1202 is mobile.The research to CDA system 1400 of hydraulic fluid pressure is controlled based on OCV is used, it is maximum Variation is about 10 milliseconds.Hydraulic response variation 1470 considers the oil in the voltage for acting on OCV822, temperature and engine Pressure.Phase position with minimum overlay 1468 provides 20 milliseconds at 3500 engine rpm of available conversion time, and Total lock bolt response time is 20 milliseconds, and the shortening between 1202 response time of time and lock bolt that this representative can be used for converting is set Count nargin.

3.4.2 the operating parameters of storage

These variables include motor mechanism shape parameter, such as variable valve timing and the lock bolt sound according to operating temperature prediction Between seasonable.

3.5. control logic

As described above, CDA conversion can only occur during small predetermined time window under specific operating condition, and The external conversion CDA system of the time window may cause critical transitions event, can cause to valve mechanism and/or other engines The damage of components.Since the engine condition of such as oil pressure, temperature, discharge and load etc can quickly change, it is possible to Real-time status is analyzed using high speed processor, they are compared with the known operating parameters of characterization operating system, makes to tie Fruit one, which is shown, to determine when to convert, and sends conversion signal.These operations per second can execute several hundred times or thousands of times.Implementing In example, which can be by application specific processor or by the existing multi-purpose vehicle(MPV) of referred to as control unit of engine (ECU) Control system executes.Typical ECU has input unit including microprocessor for analog- and digital- data, programmable storage The processing unit and output section of device and random access memory, the output section may include relay, switch and warning lamp operation.

In one embodiment, control unit of engine shown in Figure 91 (ECU) 825 receives from the defeated of multiple sensors Enter, such as valve stem movement 829, movement/position 828, latched position 827, DFHLA movement 826, oil pressure 830 and oil temperature 890. The data and conversion window of permission operation temperature and pressure etc such as giving engine speed are stored in In reservoir.Then the information of real-time collecting is compared with storage information and is analyzed to provide 825 conversion time of ECU With the logic of control.

After analyzing input, control signal is transferred to OCV 822 by ECU 825 to start conversion operation, is somebody's turn to do Conversion operation can timing at avoiding meeting the engine performance mesh of fuel economy and reduced discharge etc such as improved Target avoids critical change event simultaneously.If it is necessary, ECU 825 can also remind error condition to operator.

4. CDA-1L rocker arm assembly

Figure 99 shows the perspective view of exemplary CDA-1L rocker arm 1100.CDA-1L rocker arm 1100 is only by way of example Be shown, and will be appreciated that, the configuration of the CDA-1L rocker arm 1100 of the theme as the application be not limited to include herein The configuration of CDA-1L rocker arm 1100 shown in the drawings.

As shown in Figure 99 and 100, CDA-1L rocker arm 1100 includes having the first outer webs 1104 and the second outer webs 1106 Outer arm 1102.Inner arm 1108 is arranged between the first outer webs 1104 and the second outer webs 1106.Inner arm 1108 has first Inner webs 1110 and the second inner webs 1112.Inner arm 1108 and outer arm 1102 are both mounted on the first end of rocker arm 1100 On pivot 1114 near 1101, inner arm 1108 is fixed on outer arm 1102 by the pivot, while being in nothing in rocker arm 1100 The rotary freedom for also around the pivot 1114 being allowed to pivot when lift condition.Have shown in removing and is mounted on outer arm 1102 and inner arm Outside the embodiment of individual pivot 1114 on 1108, pivot 1114 can be integrally formed with outer arm 1102 or inner arm 1108.

CDA-1L rocker arm 1100 has the bearing 1190 including roller 1116, and the bearing is in the first inner webs 1110 and second Be mounted between inner webs 1112 on bearing axis 118, the bearing axis during the usual operation of rocker arm for by energy from rotation Cam (not shown) is transmitted to rocker arm 1100.Roller 1116, which is mounted on bearing axis 1118, allows bearing 1190 to revolve around axis 1118 Turn, this is for reducing rotation cam and friction caused by the contact of roller 1116.As described herein, roller 1116 is rotatably Be fixed on inner arm 1108, the inner arm under certain conditions again can around the pivot 1114 relative to outer arm 1102 rotate.In diagram In embodiment, bearing axis 1118 is mounted on inner arm 1108 in the bearing shaft aperture 1260 of inner arm 1108 and extends through outer arm 1102 bearing axial trough 1126.For example, when using bearing axis 118, such as bearing axis 118 does not extend across bearing axial trough 1126 But still when being mounted in the bearing shaft aperture 1260 of inner arm 1108, other configurations are possible.

When rocker arm 1100 is in no lift condition, inner arm 1108 cam (1324 in Figure 101) raised portion with It is pivoted downwards when the roller 1116 of bearing 1190 is in contact, thus pushes it relative to outer arm 1102.Axial trough 1126 allows axis Hold moving down for axis 1118 and therefore inner arm 1108 and bearing 1190.As cam continues to rotate, the raised portion of cam It is rotated away from the roller 1116 of bearing 1190, to allow bearing 1190 as bearing axis 1118 is by bearing axis torque spring 1124 It is moved up to biased.Shown in bearing axis spring 1124 be to be fixed on outer arm 1102 by spring base 1130 Torque spring on pedestal 1150.Torque spring 1124 is fixed on the second end 1103 of rocker arm 1100 nearby and has and bearing axis 1118 spring arms 1127 being in contact.As bearing axis 1118 and spring arm 1127 move down, bearing axis 1118 is along spring arm 1127 slidings.With the torque spring 1124 being fixed near the second end 1103 of rocker arm 1100 and positioned at the first end of rocker arm The configuration of pivot 1114 near 1101 mitigates in the case where bearing axis 1118 is between pivot 1114 and axis spring 1124 Quality near the first end 1101 of rocker arm.

As shown in Figure 101 and 102, valve stem 1350 also connects near the first end 1101 of rocker arm 1100 with rocker arm 1100 Touching, and the quality therefore mitigated at the first end 1101 of rocker arm 1100 alleviates the gross mass of valve mechanism (not shown), by Power needed for this reduces the rate for changing valve mechanism.It should be pointed out that other spring configurations can be used to carry out bias bearing Axis 1118, such as single continuous spring.

Figure 100 shows the exploded view of the CDA-1L rocker arm 1100 of Figure 99.The assembling in exploded view and Figure 99 in Figure 100 Show the mountable bearing 1190 on bearing axis 1118, the bearing be include combined with needle roller 1200 it is substantial cylindrical The needle bearing of roller 1116.Bearing 1190 is used to the rotary motion of cam being transmitted to rocker arm 100, which again passes movement It is delivered to for instance in the valve stem 350 in configuration shown in Figure 101 and 102.As shown in Figure 99 and 100, bearing axis 1118 can pacify In the bearing shaft aperture 1260 of inner arm 1108.In this configuration, the axial trough 1126 of outer arm 1102 receives bearing axis 1118 And allow the lost motion of bearing axis 1118 and extension ground inner arm 1108 mobile when rocker arm 1100 is loaded in no lift." lost motion " moves The dynamic movement that the rotary motion of cam is not transmitted to valve that can be considered rocker arm 1100.In the illustrated embodiment, lost motion is logical 1108 around the pivot 1114 of inner arm is crossed relative to the pivoting action of outer arm 1102 to present.

Also allow to move from cam and be transmitted to rocker arm 1100 different from other configurations of bearing 1190.For example, for Cam lift peach tip (1320 in Figure 101) interface it is smooth, surface of revolution (not shown) can not scheme in bearing 1190 substantially The position being shown in 99 relative to inner arm 1108 and rocker arm 1100 is mounted on inner arm 1108 or is integrally formed with inner arm 1108. This non-rotating surface may include the friction pad being formed on not surface of revolution.In another example, substitution can be efficiently used Bearing substitute as bearing 1190 of the bearing for example with multiple concentric rollers.

With reference to Figure 99 and 100, as foot (elephant foot) 1140 is in the first inner webs 1110 and the second inner webs 1112 Between be mounted on pivot 1114.Pivot 1114 is mounted on interior 1220 He of pivot aperture near the first end 1101 of rocker arm 1100 In outer pivot aperture 1230.The lip 1240 being formed on inner arm 1108 is prevented as foot 1140 around the pivots 1114 rotation.As foot 1140 engage as shown in Figure 102 with the end of valve stem 1350.In an alternative embodiment, it can be removed as foot 1140, and Can instead it be arranged on pivot 1114 by the interface surface of the termini-complementary with valve stem 1350.

Figure 101 and 102 respectively illustrates the side view and front view of rocker arm 1100 related with cam 1300, the cam With the lift peach tip 1320 including basic circle 1322 and lift part 1324.Roller 1116 is shown to connect with lift peach tip 1320 Touching.Double-fed type hydraulic lash adjuster (DFHLA) 110 engages near the second end 1103 of rocker arm 1100 with rocker arm 1100, and To rocker arm 1102 and the especially application of outer rocker arm 1102 upwards pressure, while reducing valve clearance.Valve stem 1350 is in rocker arm 1100 first end 1101 nearby and as 1140 engaging enough.Under usual lift condition, rocker arm 1100 periodically pushes down on valve Bar 1350, this is used to open corresponding valve (not shown).

4.1. torque spring

As described in following chapters and sections, the rocker arm 1100 in no lift condition may bear the mistake of clearance adjuster 110 Amount pumping, whether due to the beginning or other reasons of excessive oil pressure, unstable state condition.This can cause gap adjustment The effective length of device 110 increases with its inside of pressurization oil filling.This scheme can for example be sent out during engine cold starting It is raw, it can be expended for a long time without checking to settle a dispute by the parties concerned themselves and may cause permanent engine damage.? In the case of these, lock bolt 1202 possibly can not start rocker arm 1100 before clearance adjuster 110 has returned to usual working length. In this case, it adjusts adjuster 110 to upward pressure to the application of outer arm 1102, to make outer arm 1102 closer to cam 1300。

Lost motion torque spring 1124 on SRFF-1L is designed to provide sufficient power during no lift operation to keep Roller bearing 1116 is in contact with camshaft lift peach tip 1320, to ensure inner arm sub-component while retaining lock bolt gap Controlled acceleration and slow down and inner arm 1108 controllably return to latched position.It pumps situation and needs stronger torque spring 1124 Compensate other pumping force.

Rectangular lines section for torque spring 1124 is used to reduce encapsulated space, to keep component the moment of inertia low and mention For sufficient depth of section to maintain operational load.Stress calculation and FEA have been used when developing the component of torque spring 1124 With the verification experimental verification described in following chapters and sections.

Description causes the (figure of torque spring 1124 of compact design using the general rectangular line made of selected structural material 99) method is designed and manufactured.

Now, with reference to Figure 30 A, 30B and 99, torque spring 1124 is made of the generally trapezoidal shaped line 397 of shape.This is trapezoidal It is designed that line 397 to be deformed into exerting a force in winding process and be deformed into general rectangular.In 1124 quilt of torque spring After winding, the shape of obtained line can be described as similar to having the First Line 396 of general rectangular cross-sectional.Figure 99 is shown In sectional view as multiple coils 398,399 shown in two torque spring embodiments.In a preferred embodiment, line 396 With rectangular cross sectional shape, there is two long sides for being shown as vertical edge 402,404 herein and top 401 and bottom 403.It should Coil while 402 and while 404 average length can be with the ratio between top 401 and the average length of bottom 403 it is any less than 1 Value.The ratio generates the round wire winding more equal with the average length at the top 401 of coil 398 and bottom 403 than using diameter Spring more along the rigidity of coil axis of bending 400.In alternative embodiments, the cross sectional shape of line is with larger top 401 and smaller bottom 403 it is generally trapezoidal.

In the configuration, as coil is wound, the long side 402 of each coil is rested in the long side 402 of previous coil, Thus stablize torque spring 1124.All coils are maintained at stand up position by the shape and arragement construction, to prevent them Intersected with each other under stress or drift angle.

When rocker arm assembly 1100 operates, the general rectangular of torque spring 1124 or trapezoidal since they are around Figure 30 A and 30 Shown in the bending of axis 400 and generate high local stress, the especially tensile stress on top surface 401.In order to meet life requirement, It is used together the combination of technology and material.For example, torque spring can be made according to the design of the material comprising chrome alum steel alloy To improve intensity and durability.Torque spring can be heated and be quickly cooled down so that spring temper.It reduce residual parts to answer Power.The surface of the line 396,397 of torque spring is used to form using ballistic impact or " shot-peening processing " is used to answer residual compressive Power is placed in the surface of line 396,397.Then by line 396,397 wound in torque spring.Since their shot-peening is processed, obtain To torque spring can receive now than the bigger tensile stress of identical springs without using shot-peening processing and manufacturing.

4.2. torque spring seat

As shown in Figure 100, knob 1262 extends from the end of bearing axis 1118 and forms what spring arm 1127 was located therein Slot 1264.In an alternative solution, can together with include such as knob 1262 and slot 1264 for installing spring arm 1127 it The individual spring mounting pin (not shown) of the feature structure of class is used together hollow bearing axis 1118.

4.3. outer arm component

4.3.1. latch mechanism describes

Mechanism for rocker arm 1100 of selectively closing down --- it is located at the of rocker arm 1100 in an illustrated embodiment Near two ends 1103 --- it is shown as including lock bolt 1202, lock pin spring 1204, spring base 1206 and fixture in Figure 100 1208.Lock bolt 1202 is configured for mount to the inside of outer arm 1102.Lock pin spring 1204 is arranged in lock bolt 1202 and passes through lock Fasten spring base 1206 and 1208 fix in position of fixture with a bolt or latch.Once installing, lock pin spring 1204 is just towards the first end of rocker arm 1100 1101 bias lock bolts 1202, to allow lock bolt 1202 and especially joint portion 1210 is engaged with inner arm 1108, thus prevent in Arm 1108 is mobile relative to outer arm 1102.When lock bolt 1202 is engaged with inner arm in this way, rocker arm 1100 is in usual lift condition, And movement can be transmitted to valve stem from cam.

In assembled rocker arm 1100, lock bolt 1202 replaces between usual lift condition and no lift condition.Rocker arm 1100 can be enough to offset lock bolt bullet being for example configured to allow the port 1212 for applying oil pressure to the surface of lock bolt 1202 to apply Enter no lift condition when the oil pressure of the biasing force of spring 1204.When applying oil pressure, lock bolt 1202 is pushed to the of rocker arm 1100 Thus two ends 1103 extract lock bolt 1202 out from the engagement with inner arm 1108 and 1108 around the pivot 1114 of inner arm are allowed to rotate.Logical Chang Shengcheng and without under lift two states, the straight line portion 1250 of orientation fixture 1214 engages at plane 1218 with lock bolt 1202. Orientation fixture 1250 is mounted in fixture aperture 1216, and thus maintains straight line portion 1250 fixed relative to the level of rocker arm 1100 To.This constrain plane 1218 orientation be also it is horizontal, thus lock bolt 1202 is oriented in be suitable for it is constant with inner arm 1108 On the direction of engagement.

4.3.2 latch pin designs

As shown in Figure 93 A, 93B, 93C, the lock bolt 1202 of SRFF-1L rocker arm 1100 operated under no lift mode is outside It is retracted in arm 1202, and inner arm 1108 follows cam lift peach tip 1320.Under certain conditions, it is risen from no lift mode to usual The transition of journey mode can cause state shown in Figure 103, and wherein lock bolt 1202 returns to lock bolt 1202 in inner arm 1108 and usually engages Position before stretch out.

SRFF is increased and rejoins feature with the shape for the position for preventing inner arm 1108 to be blocked and being stuck in below lock bolt 1202 State.Inner arm inclined surface 1474 and lock bolt inclined surface 1472 are optimized to contact in inner arm 1108 with lock bolt inclined surface 1472 When provide smooth movement of the lock bolt 1202 to retracted position.The design avoids the pressure at switching to pressure port 506 (Figure 88) Change the damage for the latch mechanism that may cause.

4.4. system encapsulates

SRFF-1F design is absorbed in reduces valve mechanism Encapsulation Change compared with standard production layout to the maximum extent.Weight The design parameter wanted include camshaft peach tip relative to the positioned opposite and steel camshaft of SRFF roller bearing and aluminium cylinder lid it Between axially align.Steel has the Bu Tong thermally grown coefficient that camshaft peach tip can be made to shift relative to SRFF-1F with al member.

Figure 104 show single camshaft peach tip relative to SRFF-1L 1100 outer arm 1102 and bearing 1116 it is correct With bad alignment the two.Correct alignment shows camshaft lift peach tip 1320 of the center on roller bearing 1116.It is single convex Wheel shaft peach tip 1320 and SRFF-1L 1110 are designed to avoid the load of the edge on roller bearing 1,116 1482 and avoid convex It takes turns peach tip 1320 and contacts 1480 with outer arm 1102.Camshaft present in more peach tip CDA configurations loosens without the elimination of lift peach tip The tight manufacturing tolerance and assembling control of camshaft peach tip width and position, so that Camshaft Manufacturing Engineering be made to send out with II type is used in Standard cams axis in motivation is similar.

4.5.CDA-1L latch mechanism hydraulic operation

As described above, pumping is the term for extending over its state for being expected working size for describing HLA；Thus it prevents Valve returns to its seat during basic circle event.

Following Figure 105, which shows standard rod valvetrain system and acts on roll-type during camshaft basic circle event, to be referred to Power on shape follower assembly (RFF) 1496.Hydraulic lash adjuster power 1494 is by the oil pressure in backlash compensation port 1491 The combination of hydraulic lash adjuster (HLA) 1493 power and HLA internal spring force of generation.Cam reaction force 1490 is located at cam Between axis 1320 and RFF bearing.Reaction force 1492 is located between 112 end RFF 1496 and valve.Dynamic balance is necessary for this Sample: valve spring force 1492 is by the unintentional opening of anti-air-stop gate 112.If by HLA power 1494 and cam reaction force 1490 The valve reaction force 1492 of generation is more than to make the required power in place in place of valve 112, then valve 112 will during basic circle operation It rises and stays open, this is undesired.The description of the fixed arm system of standard does not include dynamic operation load.

SRFF-1L 1100 is designed in the case where being the pumping when in addition considering system under no lift mode. Pumping of the DFHLA 110 when SRFF-1L 1100 is in no lift mode will form inner arm 1108 do not return to lock bolt 1202 can be with The state for the position rejoined with inner arm 1108.

SRFF-1L 1100 is similar to standard RFF1496 (Figure 105) when SRFF-1L 1100 is in usual lift mode Ground reaction.Lock bolt gap needed for maintaining conversion SRFF-1L 1100 while preventing pumping is by applying from torque spring 1124 additional force is also to overcome HLA power in addition to already existing torsion except returning to inner arm 1108 needed for its lock bolt bonding station 1494 solve.

Figure 106 shows the balance that the power on SRFF-1L 1100 is acted on when system is in no lift mode: gap Oil pressure at compensator port 512 (Figure 88) is plus DFHLA power 1499, cam reaction force caused by plunger spring power 1498 1490 and torque spring power 1495.The torsion 1495 that spring 1124 generates is transformed to make via bearing axis 1118 and spring arm 1127 With the reactive spring force 1500 on inner arm 1108.

Torque spring 1124 in SRFF-1L rocker arm assembly 1100, which is designed to provide during no lift mode, to be enough to keep The power that roller bearing 1116 is in contact with camshaft lift peach tip 1320, with ensure inner arm 1108 controlled acceleration and deceleration and Inner arm 1108 is set to return to latched position while retaining lock bolt gap 1205.The torque spring designed for SRFF-1L 1100 1124 designs also contemplate the variation of the oil pressure when system is in no lift mode at gap compensating end mouth 512.Oil pressure is adjusted Determining to spring sizes directly affect to reduce the burden requirement to torque spring 1124 can be utilized.

Figure 107 shows the requirement to the oil pressure in backlash compensation pressure port 512.For the limited oil pressure of SRFF-1L Only required when system is in no lift mode.Synchronous the considerations of converting described in chapters and sections in front, is limited for low In 20 DEG C of temperature without lift mode.

4.6. CDA-1L pack clearance management

Figure 108 shows the lock bolt gap 1205 of SRFF-1L 1100.For single peach tip CDA system, between overall mechanical Gap 1505 is reduced to the value in monolock door bolt gap 1205, with the camshaft for designing with the CDA of more than one peach tip The sum of gap 1504 and lock bolt gap 1205 are opposite.The lock bolt gap 1205 of SRFF-1L 1100 is lock bolt 1202 and inner arm 1108 The distance between.

Figure 109 will be compared designed for the opening slope on the camshaft of three peach tip SRFF and single peach tip SRFF-1L.

Cam shaft clearance is eliminated by the design of single peach tip SRFF-1L.The elimination of cam shaft clearance 1504 allows to pass through It is formed and promotes slope shortening 1510 to advanced optimize camshaft lift profile, to allow longer lift events.For Shorten from the open slope 1506 of camshaft needed for the similar designs for using more peach tips on the open slope 1506 of the camshaft of SRFF-1L Up to 36%.

In addition, the mechanical clearance variation on SRFF-1L is since cam shaft clearance and feature associated with it are (for example, cam Manufacturing tolerance, peach tip abrasion, desired rocker piece and rocker piece and rocker piece and roller axle of the axis without lift peach tip base radius Hold the depth of parallelism) elimination and improve 39% than similar three peach tips design.

4.7. CDA-1L assembles dynamic property

4.7.1. detailed description

SRFF-1L rocker arm 1100 and system 1400 (Figure 91) are designed to meet the dynamic property of whole engine operating ranges Stability requirement.Analysis SRFF rigidity and the moment of inertia (MOI) are designed for SRFF.SRFF- is measured around pivot 1114 (Figure 99) The MOI of 1L component 1100, the pivot 1114 are the rotation axis passed through from the SRFF seat being in contact with DFHLA 110.Convex Interface between wheel 1320 and bearing 1116 measures rigidity.Figure 110 shows the measurement for calculated component MOI mark Rigidity.SRFF-1L relationship between rigidity and MOI is also compared with in the standard RFF at present on the II h type engine h of production Compared with.

4.7.2. analysis

Several designs and finite element analysis (FEA) iteration are executed so as to maximizing stiffness and reduce the end DFHLA of SRFF On MOI.Mascon component is placed on the end DFHLA of SRFF to reduce MOI to the maximum extent.Torque spring 1124 --- most heavy one of components in SRFF component --- are positioned adjacent to SRFF rotation axis.Locking mechanism also is located at Near DFHLA.The vertical section height of SRFF increases to make maximizing stiffness while minimizing MOI.

It is designed using the information on load optimization SRFF from motion modeling.Key input parameter for analysis includes valve Organization distribution, the quality of SRFF element, the moment of inertia, rigidity (being predicted by FEA), mechanical clearance, load and rate, DFHLA geometry and plunger spring and valve lift profile.Next, by valve optimal stiffness to CDA SRFF with The relationship of effective mass changes system to meet the dynamic object of prediction.The effective mass of valve represents MOI relative to SRFF Pivoting point between ratio and valve and SRFF pivot between squared-distance.The dynamic property of test is in chapters and sections below Description.

5. design verification and test

5.1. valve mechanism dynamic property result

The dynamic table of valve mechanism is referring now to control noise, vibration while the durability and performance objective for meeting engine It is critically important for dynamic and irregularity (NVH).Valve mechanism dynamic property is partly influenced by the rigidity and MOI of SRFF component.It can To readily calculate the MOI of SRFF and estimate rigidity by computer-aided engineering (CAE) technology.Dynamic valve motion also by Various factors influences, therefore is tested to obtain the assurance of high speed valve control.

Turn block testing stand for and is used for valve mechanism dynamic property.Instrument is assembled to cylinder head before the test.Oil It is heated to form and represents actual engine condition.Velocity scanning is executed from idling to 7500rpm, record is true by engine speed Fixed data.Dynamic property is determined by assessment valve-closing rate and valve rebound.For the purpose pair of monitoring load SRFF-1L carries out strain gauged.In order to consistent, load keeps constant fixed system.

The shutdown rate in place for the inlet valve that Figure 111 is shown.For display relative to engine speed it is minimum, Average and maximum rate eight continuous events obtain data.Targeted rate is shown as being commonly used in industry with regard to bit rate Maximum speed.Target is maintained with regard to bit rate is up to about 7500 engine rpm, this is illustrated for passenger vehicle engine application Acceptable dynamic control.

5.2. torque spring is verified

Torque spring is especially the key member of SRFF-1L design during running at high speed.Proof of Concept is carried out to spring To verify reliability.Three elements of spring design are tested to prove concept.Firstly, with operating temperature under high circulation state Record load loss.Spring-load loss or relaxation represent reduction of the spring-load from the on-test to off-test.It is also logical It crosses and applies highest stress level and component is made to bear high temperature to record load loss.Secondly, being tested under worst case load resistance to Long property and spring are simultaneously recycled to verify fatigue life and load loss as described above.Finally, by using minimum load bullet Spring does not pump to verify the function of lost motion spring during verifying all operating conditions of the DFHLA under CDA mode simultaneously.

Recycle torque spring under the engine operating temperature in engine oil environment in orientation fixture test.Torsion Spring is recycled with the complete stroke of the application with the preset loaded-up condition of highest to represent worst-case stress.Recycle target value quilt It is set as 25,000,000 and 50,000,000 circulations.Heat setting tests also are carried out to torque spring, wherein they are loaded on highest and answer With stress and it is maintained at 140 DEG C 50 hours and measures load loss.

Figure 112 summarizes the load loss of both cyclic test and thermal finalization test.All components are all negative with 8% maximum Lotus loss passes through, and design object is set to the loss of 10% peak load.

The result indicates that 8% peak load loses and meets design object.Many tests are shown 1% or so most Smaller load loss.All tests are all safely in the design criteria of load loss.

5.3. the pumping reliability during cylinder is closed down

Torque spring 1124 (Figure 99) is designed in system to prevent HLA from pumping to retain lock bolt when no lift mode operation Gap 1205 (Figure 108).Experimental rig is designed to hold in the range of the oil temperature and engine speed state for requiring mode to convert By the engine oil pressure at backlash compensation pressure port.

Execute the ability that confirmatory experiment retains lock bolt gap 1205 to confirm torque spring 1124 under claimed condition.It uses For measuring at valve and CDA SRFF movement, backlash compensation pressure port 52 (Figure 88) and switching to pressure port 506 (Figure 88) Oil pressure and temperature instrument to rise forwarding a motivation test.

Worst case is simulated using lower limit lost motion spring.The examination is carried out at the 3500rpm for representing maximum conversion speed It tests.Consider 58 DEG C and 130 DEG C of two operating temperatures.Test result is shown in the pump under higher than application requirement 25% pressure It send.

Figure 113 shows the minimum pumping pressure 1540 of measurement, the exhaust side being located at 58 DEG C.At 58 DEG C and 130 DEG C Air inlet and 130 DEG C at exhaust pumping pressure it is higher than the pumping pressure of the exhaust side at 58 DEG C.SRFF is in translative mode Under, there is the event under usual lift mode and the event under no lift mode.Gas is detected using short range probe Door movement, to verify the SRFF mode state under the corresponding pressure at switching to pressure port 506.Lash compensation device port 512 In pressure be gradually increased and monitor the conversion from no lift mode to usual lift mode.Record system stops the pressure of conversion Power is as pumping pressure 1540.System safely avoids pump when oil pressure maintains the 5bar or less for SRFF-1L design Pressurization pressure.Concept Testing is carried out with the high limit torque torque spring distinguishingly obtained, it is abundant to simulate worst-case fatigue design Degree condition.The design object that the Concept Testing that high load capacity torque spring carries out is met the requirements.

5.4. the verifying of the mechanical clearance during conversion durability

Mechanical clearance control is critically important for valve mechanism dynamic stability, and must during the service life of engine It must maintain.Think lock bolt load and usually lift mode and is suitable for verifying latch mechanism without the transfer test between lift mode Abrasion and performance.By the way that lock bolt is transformed into disengaged position from bonding station, SRFF is recycled under no lift mode, makes to lock Door bolt, which engages with inner arm and recycles SRFF under usual lift mode, carrys out test conversion durability.One circular in definition is that separation is right After rejoin lock bolt and operate SRFF in both modes.The durability target converted recycles into 3,000,000.3,000, 000 recycles the equivalence for representing an engine life.One time engine life is defined as 2000,000 miles --- its safety Ground be higher than 150,000 miles of standards --- equivalence.With the highest conversion speed target detection component of 3500 engine rpm with mould The worst-case dynamic load of quasi- transition period.

Figure 114 shows the variation inspected periodically a little of the mechanical clearance during test.To six cylinder engine fixture One bank of cylinder carries out the test.Due to each bank of cylinder there are three cylinder and each cylinder there are four SRFF-1L, so showing 12 profiles.The mechanical clearance extreme variations of 0.020mm are determined as to design wear down target.All SRFF-1L are shown in It is lower than the safety margin of wear down target under the equivalence of vehicle ages.The test is extended beyond the 25% of lifetime goal, at this time Component is close to maximal clearance variation targets value.

Valve mechanism dynamic property, torque spring load loss, pumping verifying and mechanical clearance are in the comparable engine longevity Hit all meets the target of SRFF-1L.Valve mechanism dynamic property in terms of shutdown rate is safely in In the maximum engine rotation speed limit of 7200rpm and the higher rotation speed limit of 7500rpm.LMS load loss shows 8% maximum Loss, is safely in 10% design object.Pumping test is executed, shows SRFF-1L design in given 5bar It is correctly operated under target oil pressure.Finally, mechanical clearance variation is safely in design object in comparable engine life It is interior.SRFF-1L meets all design requirements closed down to the cylinder in the application of petrol engine passenger car.

6. conclusion

Cylinder close down be the riding gasoline car of raising having been found fuel economy method.It is completed based on single peach tip Design, exploitation and the verifying of the cylinder deactivation system of SRFF are provided by reducing pumping loss and making a part of engine air Cylinder works to improve the ability of fuel economy with higher efficiency of combustion.The system is by maintaining engine valve, camshaft The basic framework of standard II type valve mechanism is remained with the identical central line of clearance adjuster.Engine cylinder head requirements exist Increase OCV and oily control port in cylinder head, to allow hydraulic conversion of the SRFF from usual lift mode to deactivated mode.This is System requires one OCV of each cylinder, and is normally constructed to four identical SRFF for having with for air inlet and exhaust, And each mono- DFHLA of SRFF.

SRFF-1L design provides the solution for reducing system complexity and cost.Most for SRFF-1L design Important improving technology is the modification to lost motion torque spring.LMS is designed in usual lift and without during lift both of which Maintain continuously contacting between single peach tip camshaft and SRFF.Although the torque spring requires slightly more encapsulated spaces, total a System is become by the elimination of three peach tip camshafts without so complicated.The three peach tip CDA of axial packing ratio of SRFF-1L is designed It is few, this is because the evagination wheel shaft peach for increasing the chance of the load of the edge on outer arm sliding block and interfering with inner arm is not present Point.The rocker arm rigidity levels of SRFF-1L are suitable with the rocker arm of standard production.

By placing heavier component, that is, locking mechanism and torsion in the end pivot on DFHLA Spring reduces the moment of inertia to the maximum extent.This feature is realized preferably and minimizing laterostigmatal effective mass Valve mechanism dynamic property.The system is for the 7200rpm during standard lift mode and for cylinder deactivated mode The engine speed of 3500rpm designs and verifying.Also directed to the engine at least once for being equivalent to 200,000 engine mileages Service life demonstrates component.

Although present invention illustrates the various aspects of this introduction, and in terms of describing these in some details simultaneously, Applicant is not intended to the range constraint of the requirement patent right of the application or is limited in any way this details.It is other excellent Point or remodeling will be apparent to one skilled in the art.Therefore, teachings of the present application is in its more broadly side Face is not limited to shown and description specific detail and representative device.Therefore, in the requirement patent right for not departing from applicant Under the premise of spirit herein or range, the deviation to these details can be made.In addition, above-mentioned aspect be it is illustrative, And without single feature or element for all possible combination of patent right can be required in the application or subsequent application For be essential.

Claims (18)

1. a kind of rocker arm for being engaged with the cam with single lift peach tip, comprising:

Outer arm, the outer arm include the first and second outer webs；

Inner arm, the inner arm include the first and second inner webs and are configured to for that will move the single lift peach tip from cam It is transmitted to the cam contact component of the rocker arm, the inner arm is arranged between first outer webs and second outer webs And the cam contact component is arranged between first inner webs and second inner webs；

Pivot, the inner arm is fixed to the outer arm by the pivot, described to be configured to allow the inner arm around the pivot Pivoting action of the axis relative to the outer arm；With

At least one biasing spring being fixed on the outer arm, at least one described biasing spring and the cam contact component Biased contact,

Wherein, the rocker arm further includes first end and second end, and the pivot and at least one described biasing spring are arranged in institute It states near first end.

2. rocker arm according to claim 1, wherein the rocker arm further includes lock bolt, and the lock bolt is for selectively making The inner arm is fixed relative to the outer arm, thus selectively allows the inner arm around the pivot relative to the outer arm Lost motion.

3. rocker arm according to claim 2, wherein the lock bolt includes for orienting the lock bolt and preventing the lock bolt The surface of rotation.

4. rocker arm according to claim 1, wherein at least one described biasing spring includes:

At least one torque spring, the torque spring are fixed on the outer arm and have and the cam contact element biases The spring arm of contact.

5. rocker arm according to claim 1, wherein at least one described biasing spring includes the first and second bias bullets Spring, first biasing spring is fixed in first outer webs and second biasing spring is fixed on second outside On arm, first and second biasing spring is contacted with the cam contact element biases.

6. rocker arm according to claim 1, wherein the cam contact component includes the bearing being mounted on bearing axis.

7. rocker arm according to claim 1 further includes the valve pad being mounted on the pivot.

8. rocker arm according to claim 1, wherein it is rectangle that at least one described biasing spring, which includes with substantially form, Or the silk in trapezoidal section.

9. rocker arm according to claim 1, wherein at least one described biasing spring includes processed described in increase The high strength alloy steel of compressive residual stress on the surface of at least one biasing spring.

10. rocker arm according to claim 1, wherein the cam contact component is mounted on bearing axis.

11. rocker arm according to claim 10, wherein at least one described biasing spring includes being mounted on the outer arm First and second torque springs of first and second sides, first and second torque spring and the cam contact element biases Contact.

12. rocker arm according to claim 11, wherein the one of one end of first torque spring and the second torque spring In the first and second slots for holding the two sides for being mounted on the cam contact component, to maintain the first and second torsion bullet The biased contact of spring and the cam contact component.

13. rocker arm according to claim 10, wherein the outer arm further includes lock bolt, and the lock bolt is for selectively It fixes the inner arm relative to the outer arm and thus selectively allows the inner arm around the pivot relative to described outer The lost motion of arm.

14. rocker arm according to claim 13, wherein the outer arm further includes port, and the port is used for fluid pressure Power is transmitted to the lock bolt from hydraulic fluid source.

15. rocker arm according to claim 10, wherein first and second outer webs each include pivot aperture, Bearing axial trough, fixture aperture and spring base.

16. rocker arm according to claim 10, wherein it is square that at least one described biasing spring, which includes with substantially form, The silk in shape or trapezoidal section.

17. rocker arm according to claim 10, wherein at least one described biasing spring includes the silk with a section, The section has cross-sectional length and cross-sectional width, wherein the length of the mean breadth in the average length in the section and the section Wide ratio is greater than 1.

18. rocker arm according to claim 10, wherein at least one described biasing spring includes processed to increase State the high strength alloy steel of the compressive residual stress on the surface of at least one biasing spring.