JP7302018B2 - Switched Lobe and Single Source Lost Motion Finger Followers - Google Patents

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of pending U.S. Application Serial No. 16/706,226, entitled FINGER FOLLOWER FOR LOBE SWITCHING AND SINGLE SOURCE LOST MOTION, filed Dec. 6, 2019. and claims its priority. This application claims priority to U.S. Provisional Patent Application No. 62/776,450, filed Dec. 6, 2018, entitled SWITCHING FINGER FOLLOWER. This application is further filed in U.S. Provisional Application No. 62/776,453, entitled SWITCHING FINGER FOLLOWER FOR SINGLE-SOURCE LOST MOTION, filed December 6, 2018 and May 28, 2019. It also claims priority from US Provisional Application No. 62/853,599 entitled SWITCHING FINGER FOLLOWER FOR SINGLE-SOURCE LOST MOTION INCLUDING A THREE-POSITION SWITCHING FINGER FOLLOWER. The subject matter of both these provisional applications is incorporated herein by reference in its entirety.

The present disclosure relates generally to systems and methods for operating one or more engine valves within an internal combustion engine. More specifically, the present disclosure relates to systems and methods for varying the operational relationship between a motion source, such as a cam, and one or more engine valves. Such systems and methods may include rocker arms in the form of finger followers that provide selective switching between lobes on cams and/or act as lost motion devices in engine valve mechanisms. Further, the present disclosure provides valve mechanism components such as finger followers that can switch between two or three operating states, and the use of such valve mechanism components to provide cylinder deactivation, main event positive power, or It relates to a method of operating an internal combustion engine in different operating modes such as assist events such as lost motion braking, early exhaust valve opening (EEVO), or late intake valve closing (LIVC).

Internal combustion engines are ubiquitous in many applications and industries, including transportation and trucking. Valve actuation systems for use in internal combustion engines are well known in the art. Such systems typically include one or more intervening components that transmit valve actuation motion from a source of valve actuation motion (e.g., a cam) to one or more engine valves, the intervening components being valve configure the mechanism. These valve actuation systems may primarily facilitate a positive power operating mode in which the engine cylinders generate power through the combustion process. The actuation motions of the intake and exhaust valves associated with a standard combustion cycle are typically referred to as "main event" motions. Known engine valve actuation systems may provide modified main event valve motion, such as early or late intake valve closing. In addition to primary event motion, known engine valve actuation systems provide ancillary valve actuation motions or events (e.g., exhaust motion) that allow the internal combustion engine to operate in other modes or in various positive power producing modes. gas recirculation (EGR), early exhaust valve opening (EEVO), etc.) or the internal combustion engine operates essentially as an air compressor, unfueled, to provide retarding power to help slow the vehicle. It may facilitate engine braking to occur.

In many engine systems, the valve mechanism may comprise a finger follower, which is essentially a lever that pivots with one end of the lever contacting the load, ie the engine valve, at the other end. A finger follower typically includes a motion-receiving component disposed between opposite ends of a lever to receive valve actuation motion from a source of motion (such as a cam), which in turn is applied to the load on the lever. through the end to the engine valves.

Known variations of the above finger follower components include so-called "switched" finger followers, examples of which are described in U.S. Pat. No. 7,546,822, the subject matter of which is incorporated herein by reference. incorporated herein. As shown in FIG. 1, the finger follower comprises a body 11 which in this example pivots about a hydraulic lash adjuster (HLA) 2 . Body 11 also supports lateral followers 30 which, in this example, can rotate about shaft 17 and engage locking mechanism 40 . Body 11 further supports central roller followers 20 positioned between lateral followers 30, as best shown in FIGS. As further shown in FIGS. 2 and 3, locking mechanism 40 is maintained such that locking bar 48 is maintained in an extended position thereby contacting tab 38 of lateral follower 30 (FIG. 2). or controlled to be maintained in a retracted position thereby avoiding contact with tab 38 (FIG. 3). When locking bar 48 contacts tab 38 (i.e., locked or in the ON state), lateral follower 30 is prevented from rotating about shaft 17 and thus main body 11 maintained a strong relationship with The motion imparted to the lateral follower 30 by the lateral cam lobe 9 is thus transferred to the body and ultimately to the engine valve 3 . In this case, the valve actuation motion provided by the central cam lobe 8 is not transmitted to the central roller follower 20 with which it is aligned. On the other hand, when the locking bar 48 is retracted (i.e., in the unlocked or off state), the lateral follower 30 will absorb any motion imparted by the lateral cam lobe 9 and the body It rotates freely around shaft 17 so that it is not transmitted by 11 to engine valve 3 . In this case, the valve actuation motion provided by the central cam lobe 8 is transmitted to the central roller follower 20 and thereby to the engine valve 3 .

Finger follower switching is most commonly found in lightweight automotive applications. However, due to high load events and failures due to partially engaged switching mechanisms, they have not been applied to heavy and medium duty diesel or natural gas engines. Light weight applications are also known to fail at much lower loads due to similar partial engagement problems. With reference to the example of FIGS. 2 and 3, such partial engagement occurs when locking bar 48 only partially overlaps tab 38, i.e. the position between the engagements shown in FIGS. occurs in When such partial engagement occurs, the contractile stresses between the moving parts of the locking mechanism are greatly increased and can lead to damage and/or failure of the locking mechanism.

Another disadvantage of prior art switched finger followers is that their use usually requires controls for precise timing to prevent partial engagement of their actuation or locking components. It is necessary. This may require additional cost and complexity, especially in multi-cylinder engine environments. For example, in such circumstances, each of the It may be necessary to provide a control solenoid designated for switching finger followers.

Finger follower switching can be applied to lost motion valve actuation systems. In such systems, the switching finger follower has a first position where full valve motion from a motion source such as a cam is transmitted to the engine valves and a first position where only a portion of the full valve motion is transmitted to the engine valves. can be switched between a second position where the An example of the single source lost motion lift profile described herein can be found in curve 502 of FIG. 5 of U.S. Pat. No. 9,347,383, the teachings of which are incorporated herein by this reference. incorporated. However, due to the aforementioned disadvantages, prior art switched finger followers may have limited applicability to lost motion valve actuation systems.

Accordingly, it would be advantageous to provide a system and method that addresses the aforementioned shortcomings and others in the prior art.

In response to the aforementioned challenges in the prior art, the present disclosure provides various embodiments of switched finger follower systems with improved operating characteristics, as well as improved performance and durability.

The above difficulties with conventional switching finger followers can be overcome based on various embodiments disclosed herein. The advances in the art described herein are particularly advantageous in that they eliminate the possibility of partial engagement of finger follower switching mechanism actuation components. A related advantage is the elimination of variations in the locking or supporting position of the motion receiving component on the switchable finger follower. The switchable finger follower configuration provides a positively defined position of the switchable mechanism and thus a positively defined position of the finger follower lever and thus the motion receiving component relative to the body. It has a consistent contact shape. This leads to more accurate and reliable operation and control of valve motion.

Furthermore, because the switched finger follower configurations disclosed herein are not sensitive to partial engagement of the switched mechanism, activation of the switched mechanism, they can be used at lower cost and complexity in a multi-cylinder engine environment. can be used. Thus, the improved switching mechanism and actuator eliminate the need for precise timing by control components. For example, in the case of hydraulically actuated switching mechanisms under the control of solenoids, the disclosed embodiments can eliminate the need for controlled solenoids assigned to each switching mechanism. Rather, the disclosed advances make it feasible for a single solenoid to operate a multi-cylinder switching mechanism, thereby simplifying the overall system and reducing cost.

Further, the embodiments described herein provide for one or more low-lift events in which a single valve actuation motion source (such as a cam) loses some (or all) lift, and cam lobe It is applicable to, and can be used to improve, single-source lost-motion systems that provide one or more high-lift events in which much (or all) of the lift from is transferred to the engine valves. Further, the embodiments described herein are applicable to and used to ameliorate lost motion valve actuation systems that completely lose valve motion, such as may be required in systems that utilize cylinder deactivation. can do.

Embodiments described herein can be particularly advantageous in achieving alternative valve motions such as brake late intake valve closing (LIVC), early exhaust valve opening (EEVO), internal exhaust gas recirculation (IEGR), and the like. .

According to one aspect of the present disclosure, a follower body having a pivot end and a motion transmission end, a lever adapted to pivot with respect to the follower body, a pivot end of the follower body and the follower body. an adjustable support assembly including a motion receiving component having a motion receiving surface disposed between the motion transmitting end of the follower body and a movable latch for providing selective support to the lever; A finger follower system for use in an internal combustion engine valve mechanism is provided comprising an adjustable support assembly adapted to maintain a latch in a first latched position and a second latched position. According to a further aspect, the adjustable support assembly is further adapted to allow the latch to move to the first position when the latch is not in the second position. In some applications, the adjustable support assembly may be further adapted to support the lever in two defined positions, when the latch is in the first latched position and when the latch is in the second latched position. provides engagement between the lever and the latch when the In other applications where the finger follower may facilitate complete loss of motion of the motion source, such as cylinder deactivation, the adjustable support assembly engages the latch and lever when the latch is in the first latched position. , to allow the lever to pivot freely from the latch (ie, the latch and lever do not engage) when the latch is in the second latched position.

In one implementation, a finger follower with an adjustable support assembly includes an adjustable latch or lever engagement adapted to move within the follower body to support the finger follower lever in at least one position. may include members. A lever engaging member or latch may cooperate with an actuating piston that may extend through a lateral bore of the lever engaging member. The piston obtains first and second bearing surfaces capable of providing two respective positively defined positions for the lever engaging member. In some applications, these two positions may correspond to well-defined support positions of the finger follower lever. In other applications, only one of the latch positions may support the lever, and the other position of the latch may correspond to the lever freely pivoting to a non-latch (lower) position. . The adjustable support assembly structure is adapted not to apply a load force to the actuating component when the lever engages the latch at a position other than the precisely defined position defined by the adjustable support assembly. thus avoiding damage to the actuation components and/or levers due to partial engagement.

In one implementation, the finger follower is supported for movement relative to the finger follower body and extends at an angle to the direction of latch movement to engage an arcuate surface on the lever. A lever engaging member or latch having a lever engaging member surface or latch surface is provided. The finger follower lever may comprise an arcuate surface adapted to be engaged by a planar lever engaging surface on the lever engaging member. Accordingly, the lever-engaging member surface and the lever surface are adapted to maintain substantially similar contact geometry when the lever and lever-engaging member surface are engaged. In addition to eliminating the possibility of partial engagement, these aspects provide improved durability and operation.

According to another implementation, the finger follower assembly can be applied in a single motion source lost motion engine valve mechanism environment. In some applications, the adjustable support assembly may support the finger follower lever in at least two positions, at least one of which may be the lost motion position. In other applications, the adjustable support assembly supports the finger follower lever in at least one position and in another position the finger follower lever is free to pivot such that motion of the motion source is not transmitted to the engine valve. (as may be the case for cylinder deactivation applications). The biasing assembly may include at least one resilient element disposed between at least one spring support on the follower body and at least one spring support on the lever. A movement limiter on the body may limit upward movement of the lever. One or more precisely defined lever support positions are implemented by the interaction of the lever engaging member and the actuating piston to provide full or partial transmission (or full or partial loss).

According to another implementation, the finger follower may comprise an eccentric pivot mount that may provide adjustment of the position of the finger follower lever relative to the follower body.

According to yet another aspect of the present disclosure, a method is provided for controlling operation of at least one valve of an internal combustion engine using a valve mechanism component disposed between a motion source and a motion receiving component. , a valve mechanism component including a body, a lever adapted to pivot relative to the body, and an adjustable support assembly for providing selective support to the lever, the valve mechanism component comprising , configurable to adopt at least two states of operation by actuation of the adjustable support assembly, the method comprising: moving the valve mechanism component from a motion source to a motion receiving component in a first motion; configuring the engine to assume a first state in which the valve mechanism component is in the first state; operating the engine in a first mode of operation when the valve mechanism component is in the first state; , configuring the valve mechanism component to adopt a second state in which the valve mechanism component transmits a second range of motion from the motion source to the motion receiving component; and when the valve mechanism component is in the second state; operating the valve mechanism component in the second mode of operation.

According to one example implementation, the adjustable support assembly may provide three corresponding states or positions of the finger follower, each state or position including a three-position latch to accommodate a corresponding range of motion. A motion source, such as a cam, can have multiple lobes and interact with the finger followers to achieve different valve motions and thus different engine operating modes.

According to one example, a three-position finger follower may be configured in a first state to support engine operation in cylinder deactivation mode. The finger follower may further be configured with a second state that supports engine operation in the main event positive power mode. The figure follower can be further configured with a third state that supports engine operation in auxiliary valve motion modes, including lost motion braking, late intake valve closing (LIVC), or early exhaust valve opening (EEVO). ) can be included.

According to another example, a three-position finger follower may be configured in a first state to support engine operation in lost motion braking mode. The finger follower may be further configured with a second state that supports engine operation in EEVO mode. The figure follower can be further configured with a third state that supports engine operation in the main event positive power mode.

Other aspects and advantages of the present disclosure will become apparent to those skilled in the art from the following detailed description, and the above aspects should not be considered exhaustive or limiting. The above general description and the following detailed description are intended to provide examples of the inventive aspects of the disclosure, and in no way limit or constrain the scope defined in the appended claims. should not be construed as

The above and other attendant advantages and features of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, in which like reference numerals represent like elements throughout. The descriptions and embodiments are intended as illustrative examples in accordance with aspects of the present disclosure and are intended to be limited in the scope of the invention as set forth in the claims appended hereto. It will be understood that no In the description of the figures that follow, all illustrations relate to features that are examples according to aspects of the present disclosure, unless otherwise noted.

1 is a perspective view of an example prior art switching finger follower and engine valve mechanism environment, which may be suitable for implementing aspects of the present disclosure; FIG. Figure 2 is a cross-sectional view of the finger follower system of Figure 1 in the "on" state; Figure 2 is a cross-sectional view of the finger follower system of Figure 1 in the "off" state; FIG. 3 is an assembled perspective view of an example finger follower assembly; 5 is an exploded perspective view of the example finger follower assembly of FIG. 4; FIG. FIG. 13 is a detailed exploded perspective view of the adjustable support assembly of the finger follower; Figure 5 is a longitudinal cross-sectional view of the finger follower assembly of Figure 4 in a first state, which may be an "off" or "unlocked" state; 5 is a cross-sectional view of the finger follower assembly of FIG. 4 in a first state; FIG. Figure 5 is a longitudinal cross-sectional view of the finger follower assembly of Figure 4 in a second state, which may be an "on" or "locked" state; Figure 5 is a cross-sectional view of the finger follower assembly of Figure 4 in a second state; FIG. 11 is an assembled perspective view of a finger follower assembly according to a second embodiment in application as a lost motion device; 12 is an exploded perspective view of the lost motion finger follower assembly of FIG. 11; FIG. Figure 12 is a longitudinal cross-sectional view of the finger follower assembly of Figure 11 in a first condition, which may be the loss of some or all movement of the valve mechanism; Figure 12 is a longitudinal cross-sectional view of the finger follower assembly of Figure 11 in a second condition, which may be a condition in which some or all of the movement of the valve mechanism is transmitted; FIG. 10 is a longitudinal cross-sectional view of another embodiment of a finger follower assembly that allows the lever to pivot freely from the support assembly to facilitate complete loss of motion; Fig. 10 is a perspective view showing an eccentric pivot mount; Figure 17 is a cross-sectional view of the pivot mount of Figure 16; FIG. 11 is an end cross-sectional view of a three-position switching finger follower; 19 shows an exemplary first implementation of the three-position embodiment according to FIG. 18; 19 shows an exemplary first implementation of the three-position embodiment according to FIG. 18; 19 shows an exemplary first implementation of the three-position embodiment according to FIG. 18; 19 shows an exemplary second implementation of the three-position embodiment according to FIG. 18; FIG. 11 illustrates a cross-sectional view of an alternative embodiment of a three-position valve mechanism component compatible with a Type III rocker configuration; 4 shows profiles of three-position valve mechanism components to achieve various engine operating modes; 4 illustrates exemplary cam profiles, lost motion, and valve lift motion that may be achieved in three different operating conditions using a three-position finger follower according to aspects of the present disclosure; FIG. 3 illustrates the steps of an exemplary method for performing cylinder deactivation, main event positive power, and auxiliary events such as lost motion braking, LIVC, EEVO, etc. in an internal combustion engine using a 3-position finger follower. 4 shows steps of an exemplary method for performing main event positive power, EEVO, and lost motion braking using a 3-position finger follower in an internal combustion engine using a 3-position finger follower.

FIG. 4 is a perspective view of an exemplary assembled switching finger follower system 100 according to this disclosure. FIG. 5 is an exploded perspective view of the same system. In particular, the switching finger follower may comprise a body or housing 400 arranged to support or house various other system components. The body 400 is adapted to contact or engage a pivot shaft that may include an HLA from a motion transmitting end or valve engaging end 410 adapted to contact or engage one or more engine valves. It may extend longitudinally to a rounded pivot end 420 . Body 400 may further include a pair of lateral longitudinally extending arms 402 and 404 defining a lever recess or pocket 406 therebetween. Arms 402 and 404 may include respective pivot pin receiving holes 403 and 405 at valve engaging end 410 for securing lever pivot pin 412 therein. A pair of lateral roller followers 430 and 434 may be secured to arms 402 and 404 via shafts 432 and 436, respectively. Lateral roller followers 430, 434 are configured to receive valve actuating motion from a complementarily configured valving motion source, for example, a motion source similar to lateral cam lobe 9 shown in FIG. Although the lateral followers are shown in roller form, the present disclosure need not be limited in this regard, as the lateral followers can be implemented, for example, as flat follower contact areas extending from the body 400. It is understood that there is no

Body 400 may further support a lever 450 having a fixed end 452 that may be mounted in pivotal cooperation with follower body 400 and extending longitudinally to a free end 460 . A fixed end of the lever 450 may be fixed to a lever pivot pin 412 fixed to the arms 402 , 404 of the body 400 .

Lever 450 may have a shape that complements recess or pocket 406 in body 400, thereby providing nested positioning within body 400 and an overall compact finger follower configuration. Lever 450 may be formed as a precision single stamped metal (ie, steel) component having a generally concave shape with a bottom wall 454 and an integral outer wall 456 extending from bottom wall 454 . A central portion of lever 450 can support and house a motion receiving component that is cooperatively associated with the lever. The motion-receiving component can be a central roller follower 440 supported on a shaft 442 attached to lever 450 . Alternatively, a motion receiving component cooperatively associated with the lever is directly on or mounted on the lever and is adapted to directly engage the motion source or a valve mechanism component cooperating with the motion source. contact surface. A recess or notch 458 may be formed in the bottom wall 454 to accommodate the central roller follower 440 . The free end 460 of the lever is arcuate or otherwise curved with an arcuate or otherwise curved end face 462 for selective engagement with an adjustable support assembly 500 integrated into the body 400 as described. It may have a similarly curved lever end wall 461 . End wall 461 may extend and contour to have a smooth transition with bottom wall 454 . Lever end wall 461 may extend between reduced lateral dimensions between opposing portions of outer wall 456, thereby providing additional stability and strength as well as reducing end wall 461 during operation. can reduce the possibility of deformation of

As will be appreciated, the central roller follower 440 may be configured to selectively receive valve actuation motion from a complementarily configured source of valve actuation motion. For example, referring to the engine environment described above with respect to FIG. 1, central roller follower 440 may receive valve actuation motion from a central cam lobe, similar to cam lobe 8 in FIG. As will be appreciated, according to aspects of the present disclosure, the finger follower configurations described herein provide wider lateral and It has the advantage of allowing a central follower dimension. This may allow for a wider cam surface, thus reducing contact stress and wear between the cam and follower, for example.

6-10, the pivot end 420 of the finger follower body 400 has a longitudinal bore 422 formed therein and a lateral bore 422 for receiving the components of the adjustable support assembly 500. Holes 424 may be included. Pivoting end 420 also abuts a suitable pivoting assembly, such as a hydraulic lash adjuster having a post adapted to fit within a recess or pocket 426, and is pressurized as further described. It may include a recess or pocket 426 containing a hydraulic passageway 428 (FIG. 8) for delivering hydraulic fluid (oil) to the finger follower.

Adjustable support assembly 500 may include a lever engagement member or latch 510 and an actuation piston 530 cooperatively associated therewith. A lever engagement member or latch 510 may be disposed within a longitudinal bore 422 that includes a cylindrical guide surface 423 for supporting and facilitating sliding movement of the lever engagement member or latch 510 . Lever-engaging member or latch 510 is generally cylindrical including an outer cylindrical surface 512 and a substantially planar lever-engaging surface 514 that may extend at an angle to the axis of lever-engaging member or latch 510 . can have the shape A lateral actuation piston receiving bore 516 may extend through the lever engagement member or latch 510 for receiving and cooperating with an actuation piston 530 . Additionally, the lever engaging member or latch 510 has chamfers transitioning from the outer surface of the lever engaging member or latch 510 to the piston receiving bore 516 on each side to provide smooth interaction with the surface of the piston 530. surface 518 (FIG. 5). The chamfered surface 518 also provides a reduced width of the transverse piston receiving bore 516, thereby reducing the width of the transverse bore 516 for engagement with the reduced diameter piston surface 532. It will be appreciated that it eliminates the need for precise alignment with piston 530 .

Actuating piston 530 may include a first bearing surface 532 adapted to engage and support lever engaging member or latch 510 in a first position within longitudinal bore 422, the first position being , unlocked or lowered or retracted positions of lever 450 and central follower 440 relative to body 400 . First support surface 532 may be a cylindrical surface having a first diameter. The actuation piston 530 may also include a second bearing surface 534 adapted to engage and support the lever engaging member or latch 510 in a second position within the longitudinal bore 422, the second position being may correspond to locked or raised or deployed positions of lever 450 and central follower 440 relative to body 400 . The second support surface is larger than the first diameter of the first support surface and substantially corresponds to the diameter of the transverse bore 424 in the body 400 and substantially corresponds to the diameter of the lateral actuation piston receiving bore 516. It may be a cylindrical surface having a second diameter that Disposed between the first support surface 532 and the second support surface 534 may be a transition surface 536 on the working piston 530, which transition surface 536 provides locking action of the working piston. The medium may be generally tapered or conical adapted to provide a smooth transition from the first support position to the second position of the lever engagement member. The transition surface 536 also unlocks the actuation piston when the actuation piston can be in an intermediate position between fully retracted and fully extended positions within the transverse bore 424, as will be described in more detail below. Return to position can be facilitated.

The operation of adjustable support assembly 500 will now be described. FIGS. 7 and 8 show an exemplary switching finger follower in an “unlocked” or off state, with lever 450 in a lower position relative to body 400 . Piston 530 is fully retracted into transverse bore 424 and bottoms out on end wall 425 of transverse bore 424 . A biasing device, such as coil spring 533, may be disposed in transverse bore 424 and engage spring seat 539 to bias the piston toward the retracted position. This position aligns the first bearing surface 532 of the actuation piston 530 with the lateral piston receiving bore 516 of the lever engagement member or latch 510 . A lever engaging member or latch 510 is retracted into the longitudinal bore such that contact surface 514 is positioned to contact lever end surface 462 along a first line of contact, the first line of contact being the lever. It may be a lower (ie, below the axis) location on surface 514 of engagement member or latch 510 . A spring retaining cap 535 may be attached (ie, press fit or threaded) to body 400 to retain spring 533 and piston 530 within lateral bore 424 .

As shown in FIG. 8, pivot receiving pocket 426 of body 400 may be hydraulically connected to lateral bore 424 via hydraulic passageway 428 . When pressurized hydraulic fluid is not supplied to the first transverse bore via passage 428, a biasing element (not shown) biases piston 530 leftward as shown in FIG. obtain. In this state, reduced diameter surface 532 of piston 530 is aligned with lever engaging member or latch 510 . Therefore, because lever 450 is maintained in a lower position relative to body 400, central roller follower 440 is maintained in a lower position as well, thereby increasing the distance between central roller follower 440 and its corresponding source of valve actuation motion. establish a rush. This lash space eliminates valve actuation motion that would otherwise be applied to the central roller follower 440 .

9 and 10, according to aspects of the present disclosure, adjustable support assembly 500 can be actuated to support lever 450 relative to body 400 in a second position. When pressurized hydraulic fluid is provided to lateral bore 424 via passageway 428, for example, from a passageway in a support HLA (not shown), a leftward bias applied to piston 530 will cause piston 530 to can be overcome such that the second bearing surface 536 is displaced to a point where it is aligned with and supports the lever engagement member or latch 510 . It will be appreciated from this disclosure that other actuation techniques may be utilized in place of or in addition to the hydraulic fluid actuation systems described by the examples herein. For example, pneumatic, electromagnetic, or purely mechanical interacting components can be utilized to provide the motive force for actuation of elements such as the actuating piston or pin 530 described. Transition surface 536 allows lever engagement member 510 to move from the first latched position to the second latched position (to the right in FIG. 9) as piston 530 moves. As a result, as best shown in FIG. 9, lever end face 462 may now contact slide member surface 514 at a relatively high point on slide member contact surface 506 . Lever 450 and central roller follower 440 are thus supported in a second position, in this case higher than the position corresponding to the first (retracted) position of lever support member 510, and central roller follower 440 Any rush between follower 440 and its corresponding source of valve actuation motion can be absorbed. In this manner, valve actuation motion is applied to central roller follower 440 and subsequently transmitted to body 400 by contact between lever 450 and slide member 510 and further contact between slide member 510 and body 400. be done. As will be appreciated from this disclosure and will be described in more detail below in the context of lost motion, cylinder deactivation applications, the first and second positions of the latch may define alternate states of the lever. More specifically, in the context of lost motion cylinder deactivation, the first position of the latch may be a "normal" operating state that facilitates raising the lever to a higher position with respect to the follower body, and the position of the latch. A second position may be a (retracted) "Lost Motion Activated" operating state, in which the lever does not engage the latch at all, but instead may be lowered to a rest position relative to the follower body (i.e., no movement of the lever). facilitated by a stop that defines the lower limit). In this state, the lever is in a lower position so that all valve motion otherwise transmitted by the motion source can be "lost" or absorbed by the finger follower system.

According to one aspect of the present disclosure, adjustable support assembly 500 provides the advantage of distributing the load applied by lever 450 (indicated by the heavy black arrows in FIG. 9). More specifically, the vertical component of the load is distributed to body 400 via the engagement of outer surface 512 of lever engaging member (also referred to herein as a latch) 510 with the inner surface of longitudinal bore 422 . (indicated by the vertical dashed arrow). The horizontal component of the load (indicated by the horizontal dashed arrow) is distributed to the piston 530 via the lever engagement member or latch 510 . As will be appreciated, the angle of lever engaging surface 514 is selected such that the majority of the load is distributed over a larger area of the guide surface of longitudinal bore 422, with a smaller component of the load being produced by actuating piston 530. obtain. Additionally, it will be appreciated that this load distribution occurs regardless of the position of the lever engaging member or latch 510 within the longitudinal bore 422 . Moreover, due to the unique interaction of lever end face 462 and surface 514 of lever engaging member or latch 510, the potential for partial engagement between these elements is effectively eliminated. Further, as shown, by providing lever end surface 462 with a substantially arcuate shape, the contact stress between lever engaging member 530 and lever end surface 462 may be controlled, i.e., the contact area between the elements can remain substantially constant in all operating states and positions of the lever relative to the body, i.e., regardless of the position at which the lever engaging member 530 engages the lever end surface 462. Lever engaging member surface 514 and lever end surface 462 may be adapted to maintain substantially similar contact geometry at all locations of the lever in contact with lever engaging member surface 514 . This improves durability and performance.

Moreover, the unique interaction between the support surface of piston 530 and the lever engaging member or latch 510 provides lever 450 with two positively defined and switched support positions, which position, and thus actuation, provides two positively defined support positions. The corresponding movement of the valve can be controlled very precisely. Additionally, the reduced forces involved in the interaction of the piston 530 and the lever engagement member 530 improve durability and performance consistency. A further related advantage of an exemplary adjustable support assembly according to aspects of the present disclosure eliminates the potential for excessive contact stress between intermediate engagement positions between lever engagement member 530 and lever 450 . Such intermediate positions would be positions other than either the first or second engagement position as described above. As will be appreciated, there is only one position in which the lever engagement member 530 could be supported when the piston 530 is in the retracted position. When the lever engaging member is not in the first retracted position, no reaction force from piston surface 532 is provided. Thus, after piston 530 is retracted, lever engaging member 530 may remain in the second position or may not fully retract into longitudinal bore 422, lever engaging member 530 may be in the first position. When the load of the motion source is transmitted to lever 450 up to , no reaction force is provided. In this way, the system avoids applying a load force when the actuating component is not in the first or second positions. Stated another way, lever support assembly 500 is adapted to provide support to the lever only in the first position or the second position. That is, when the piston 1530 is in the first position and the lever engaging member 1510 is in a position not engaging the piston, the system expects the lever engaging member 1510 to “float” within the longitudinal bore 422 . No reaction force is provided by the piston on the lever engagement member until enabled and properly seated against the piston 1530 . Accordingly, the adjustable support assembly is adapted to allow movement of the lever to the first position when the lever is not in the first position or the second position. This arrangement eliminates damage to the support components and provides reliable and durable operation of the switching finger follower.

11-13 illustrate a second implementation embodying additional aspects according to the present disclosure. This implementation is useful in an engine environment that uses a single source of motion, such as a cam, with one or more low-lift events, such as auxiliary events, where some lift may be lost, and more (or all) from the cam lobe. ) can be useful as a lost motion device to provide high lift events, such as combustion main events, where lift is transferred to the engine valves. An exemplary lost motion engine environment is described, for example, in US Pat. No. 9,347,383, the subject matter of which is incorporated herein by reference in its entirety. As will be appreciated, in such applications, instead of the combination of central 8 and lateral cam lobes 9 in the environment described above with respect to FIGS. 1-3, a single cam profile having multiple lobes thereon is used. used.

FIG. 11 is a perspective view of an exemplary assembled lost motion finger follower system 1000, according to one aspect of the present disclosure. FIG. 12 is an exploded perspective view of the same exemplary system. A switched finger follower may have a general structure similar to the embodiments described above with respect to FIGS. 4-10. The structure and operation of adjustable support assembly 1500, including piston 1530, lever engaging member 1510, and their interaction with end surface 1462, are similar to the implementations described above and are applicable to this embodiment. It is understood and need not be repeated. It will be appreciated, however, that the structure of body 1400 and lever 1450 may be modified to facilitate the functioning of the system in lost motion applications, as described below.

One modification may include the addition of a biasing assembly that cooperates with body 1400 and lever 1450 and is adapted to bias lever 1450 away from body 1400 toward a raised or deployed position. Body 1400 may include a pair of laterally extending spring retaining flanges 1402 and 1404 . Respective elastic elements (eg, coil springs) 1422 and 1424 are held between flanges, thus pushing lever 1450 and central roller follower 1440 in a direction toward the source of motion (i.e., upward in FIGS. 11 and 12). energize.

In another modification, travel limiter 1425 may be disposed on pivot end 1430 of body 1400 to limit rotation of lever 1450 away from body 1400 by engaging upper surface 1463 of lever end wall 1461. can be integrally formed therewith to Although travel stop 1425 is shown as an integral component of body 1400, travel stop 1425 may be attached to body 1400 or as a separate component coupled thereto via another component. It will be appreciated that it can be implemented. Additionally, travel stop 1425 may include an adjustable feature such as an adjustment screw that threads into the illustrated limit and is secured with a retaining nut to allow the upper limit of travel of lever 1450 to be adjusted.

As is known in the art, when a hydraulic lash adjuster (HLA) is incorporated into a single source lost motion valve mechanism, expansion of the HLA during these operating conditions when valve actuation motion is lost is There is a need to prevent, ie, prevent the HLA from occupying purposely provided lash space to selectively lose actuation motion of the valve. In the illustrated embodiment, this is done so that the force exerted by these elements on lever 1450 is greater than the force exhibited by the associated HLA as it expands to absorb the available lash. Accomplished by operation of selected elastic elements 1422 and 1424 . In this manner, the elastic elements 1422, 1424 load the HLA sufficiently to prevent unwanted expansion of the HLA. On the other hand, uncontrolled application of the force provided by elastic elements 1422 and 1424 to the HLA can cause excessive compression or bleed-down of the HLA. Thus, the travel-limiting stop 1425 can limit the travel of the lever 1450 and, as a result, the force exerted by the elastic elements 1422, 1424 on the associated HLA. The travel distance of lever 1450 allowed by travel stop 1425 is lost when the HLA is operating to occupy the lash space in the valve mechanism when lever 1450 opposes travel stop 1425. The movement of motion is preferably controlled to equal the lost valve lift event. For example, if the travel stop 1425 allows excessive stroke of the lever 1450, the lost motion operating condition loses excessive motion and relatively high lift valve events (e.g., main events) have excessive lash. , resulting in undesirably lower valve lift and higher valve seating velocity. Conversely, if travel stop 1425 allows insufficient stroke of lever 1450, an insufficient amount of lash space will be established during lost motion operation and valve actuation motion will nevertheless be lost. is transmitted to the engine valves by finger followers. This can lead to undesirable results such as valve lift and duration changes, and in some cases can add unnecessary lift events when they are not desired. In embodiments where travel stop 1425 is attached to body 1400 (rather than being integrally formed therewith), travel stop 1425 is adjustable such that the stroke of lever 1450 can be precisely controlled. can be

Yet another modification, compared to the embodiments described above with respect to FIGS. 4-10, is that in a single motion source environment where finger follower system 1000 functions as a lost motion device, such elements are not required. Elimination of lateral roller followers can be included because there are cases.

In lost motion applications, adjustable support assembly 1500 provides at least two very precisely controlled positions of lever 1450 relative to finger follower body 1400, similar to the operations described above with respect to FIGS. obtain. These two controlled positions can provide two levels of motion transfer from the motion source to the actuation valve. A first position may, for example, correspond to partial motion transfer and a second position may correspond to full motion transfer. As will be appreciated from this disclosure, the described embodiments ensure that all valve motion that would otherwise be transmitted from the motion source (cam) is "lost" or absorbed by the finger follower system. can be adapted for lost motion applications. In such a case, the lever may have only one precisely defined position of engagement with the latch 510, the lever either not engaging the lever or the latch engaging the lever and A second position can be taken in which the lever is supported sufficiently low that no valve lift is transmitted from the source of motion. The disengaged configuration of the lever may eliminate the need for precision in manufacturing to define at least the second disengaged position of the lever.

13, with lever engaging member 1510 in the retracted position and supported on the smaller diameter of piston 1530, lever surface 1462 contacts lever engaging member surface 1514 at a relatively low point. do. Lever 1450 and roller follower 1440 are maintained in a lower position relative to body 1400, thereby establishing lash between roller follower 1440 and its corresponding source of valve actuation motion. Because of this lash space, relatively low-lift valve actuation motion that would otherwise be applied to central roller follower 1440 is lost, but relatively high-lift valve actuation motion is still received by roller follower 1440 and finger It is transmitted to the follower body 1400 and ultimately to the engaged valve.

Still referring to FIG. 14, with the piston 1530 hydraulically actuated to overcome the spring-biased force, the piston is forced to the point where its entire diameter completely occupies the lateral bore of the lever engagement member 1510. may move. Lever engaging member 1510 is thus in a fully deployed position and lever 1450 and follower 1440 are maintained at a relatively high position to absorb any lash between follower 1440 and the source of valve actuation motion. In this condition, relatively low lift valve actuation motion as well as relatively high lift valve actuation motion is applied to roller follower 1440 and transmitted to finger follower body 1400 and ultimately to the valve engaged thereby. transmitted.

In addition to the precisely controlled position of the lever 1450 relative to the finger follower body 1400 described above, and precise control as a result of the lost motion capability provided by the finger follower system, the above configuration also provides intermediate positioning of the lever 1450. , thus providing the advantage of eliminating intermediate transmission of valve motion. As described in detail above regarding the operation of adjustable support assembly 500 in the embodiment of FIGS. , can be adapted to provide support at two defined locations.

FIG. 15 illustrates another embodiment according to aspects of the present disclosure, which may be useful in applications such as cylinder deactivation applications where complete loss of valve motion may be facilitated. In this embodiment, the lower lever positioning is such that the lever pivots freely from the latch 2510 and is therefore lower relative to the follower body than provided in previously described embodiments ( Second) lever position is facilitated by the adjustable support assembly 2500 . FIG. 15 shows latch 2510 in a first position, with larger diameter surface 2534 engaging the lateral aperture of latch 2510 and supporting it in its shown extended position, latch surface 2514 lever surface 2462 and lever surface 2462 . , thereby retaining lever 2450 in the (first) position shown. This position may correspond to the "de-energized" state of actuator piston 2530 (ie, the "normally latched" lever position), with lever 2450 positioned to transmit normal valve motion. According to aspects of this embodiment, when the piston 2530 is energized, the smaller diameter surface 2532 aligns with the lateral bore of the latch and the latch 2510 is retracted (i.e., moved up and to the left in FIG. 15). to do). This position of latch 2510 allows lever 2450 to be completely free to pivot to a lower position where it does not engage latch 2510 . Therefore, this configuration may be useful in applications such as cylinder deactivation applications where such low lever positions are required to completely eliminate valve motion.

Figures 16 and 17 show details of a pivot pin 1412 that can be used in any of the previously described implementations. As shown, pivot member 1412 includes an eccentric shaft 920 formed therein. In particular, the axis of shaft 920 is not aligned with the axis of pivot member 912 . The eccentric shaft 920 is also provided with a threaded mounting hole 922 . As best shown in FIG. 17, pivot member 912 may be supported by body 400 with lever 408 mounted for rotation on eccentric shaft 920 . A suitable fastener 1002 can be used to secure the assembly of pivot member 912 , lever 408 and body 400 . By selectively rotating pivot member 912, the position of eccentric shaft 922 is shifted relative to body 1400 such that the pivot end of lever 408 is likewise shifted upward or downward relative to body 1400. may be moved. In this way, the pivot member 912 can be used to adjust or control the position of the lever 1450 to work with different cam profiles to establish different lash settings or to reduce precision and cost to manufacture. process can be enabled.

As will be appreciated, the shape of the interacting surfaces of lever engaging member or latch 510, actuating piston 530, lever end surface 462, and other surfaces described herein, without departing from the spirit and scope of the present invention. Various geometric variations in can be provided. For example, lever engaging member or latch 510 may comprise a curved or arcuate surface and lever 450 may comprise a flat surface. Further, although described as cylindrical elements, the piston and lever engaging member may have square or rectangular or other cross-sectional shapes.

As a further example, although lever engagement member 530 is shown and described as operating under the control of mechanical interaction with in turn hydraulically controlled piston 530, it is possible to control the lever engagement member. It is understood that other configurations of may be employed. For example, the lever engaging member 530 may be biased to its unlocked or off state by a resilient element, and the hydraulic passageway may be connected to the hole in which the lever engaging member 530 resides, so that a Application of hydraulic fluid extends lever engagement member 530 to its locked or on state, while a locked amount of hydraulic fluid in the bore of the slide member extends lever engagement member 530 to its extended position. maintain. As another example, although lever contact surface 462 is shown as having an arcuate shape, this is not a requirement and other surface configurations, such as angled, semi-circular, etc., can be employed as well. Further, the configuration of body 400 and lever 450 can be reversed, i.e., the central body is provided with an outer movable arm, which is replaced by one or more similarly configured sliding members as described above. It will be appreciated that it can be placed in an unlocked/off state or a locked/on state for use.

Referring now to FIG. 18, actuating piston 1804 is shown according to various three-position embodiments. As shown, piston 1804 includes, from right to left, a minimum diameter portion 1806, an intermediate diameter portion 1808, and a maximum diameter portion 1810 as shown in FIG. 8, the embodiment of FIG. 18 includes one or more hydraulic passages, such as hydraulic passage 428 of FIG. 8, and one or more springs or one or more springs, such as biasing element 533 of FIG. Biasing elements may be included, which may be used to control the alignment of any of the piston portions 1806, 1808, 1810 with the slide member 1802 in a manner substantially similar to that described above with respect to FIG. can. For example, when no hydraulic pressure is applied to the left end of actuation piston 1804 (as shown in FIG. 18), the resilient element on the right end of piston 1804 causes piston 1804 to index as far to the left as possible. aligns the smallest diameter portion 1806 with the slide member 1802 . Through application of a first pressure to the left end of piston 1804 , the leftward biasing force applied by the resilient element causes piston 1804 to move rightward such that intermediate diameter portion 1808 of piston 1804 aligns with slide member 1802 . can be overcome to a sufficient extent to allow it to be indexed to Applying a second pressure, higher than the first pressure, to the left end of piston 1804 further overcomes the biasing force of the resilient element, causing piston 1804 to move upwards such that maximum diameter portion 1810 of piston 1804 aligns with slide member 1802 . is indexed further to the right.

Thus, when the minimum diameter portion 1806 is aligned with the slide member 1802, the slide member 1802 can be retracted into its longitudinal bore to the maximum extent allowed by the piston 1804 (maximum retraction state). On the other hand, when the largest diameter portion 1810 is aligned with the slide member 1802 , the slide member 1802 cannot (or can only minimally) retract into its longitudinal bore, but instead is pushed by the piston 1804 . It is held in an extended position, exiting the longitudinal hole to the maximum extent possible (maximum extension state). Finally, when intermediate diameter portion 1808 is aligned with slide member 1802, slide member 1802 is partially retracted into its longitudinal bore, i.e., to a position between the maximum retracted state and the maximum extended state. can be done. Various examples of such operations are further illustrated in FIGS. 19-22.

19-21 show a first implementation of a three position switching finger follower in which the slide member 1802 has stepped contact surfaces 1902,1904. Additionally, lever arm 408 includes a contact surface 1906 configured to complementarily engage either of stepped contact surfaces 1902 , 1904 . One or more resilient elements, such as springs or other biasing mechanisms (eg, hydraulic passages), can be provided to generally bias the slide member 1802 away from the lever arm to its maximum retracted state. In FIG. 19, the smallest diameter portion 1806 of piston 1804 is aligned with slide member 1802 so that slide member 1802 can assume its maximum retracted state. (Note that in FIGS. 19-21, the lateral bores of slide member 1802 and piston 1804 have been omitted for clarity.) It is retracted to the extent that surface 1906 is prevented from contacting slide member 1802 in any way. In this case, downward deflection of lever arm 408 is limited when contact surface 1906 contacts lower stop 1908 of body 402 . The illustrated switched finger follower, configured in this manner, loses the maximum amount of motion applied to it, and may correspond, for example, to an operating mode in which the corresponding cylinder is deactivated.

FIG. 19 also shows a sample motion source 1920 shown displaced from its normal operating position relative to the finger follower for clarity. Motion source 1920 may be a rotating cam having a primary event lobe 1922 and two secondary lobes 1922 and 1924 . It will be appreciated that the secondary lobes 1922 and 1924 may be positioned on the cam body at various rotational positions to achieve various lift profiles. Cams 1920 can interact with follower rollers, finger followers, to impart motion. Motion of the finger follower is transmitted or transmitted to valve 1930 .

The cam or motion source 1920 shown in FIG. 19 may be combined with a three-state finger follower to selectively achieve, for example, main event valve lift, lost motion braking valve lift, and cylinder deactivation (no valve lift) operation. can be used It is recognized that alternative valve lift motions can be achieved with suitable modifications of the motion source profile (cam lobe) and motion transfer attributes of each state of the three-state finger follower. For example, if CDA is not utilized in the third state and a different lift event such as EEVO is desired, the motion source may have different profiles such as those shown and described below with respect to FIG.

FIG. 20 shows where the intermediate diameter portion 1808 of the piston 1804 is aligned with the slide member 1802 such that the slide member 1802 extends from the longitudinal bore greater than its maximum retraction and less than its maximum extension. . In this state, slide member 1802 extends sufficiently to allow contact between first stepped contact surface 1902 of slide member 1802 and contact surface 1906 of lever arm 408 . The illustrated switching finger follower, configured in this manner, has an applied motion below the first level (i.e., the motion required to bring the contact surface 1906 into contact with the first stepped contact surface 1902). less motion), but transmits applied motion above the first level. For example, in this mode of operation, a switching finger follower may transmit relatively high valve lift such as main event lift, but lose relatively low lift such as braking or other auxiliary valve events.

FIG. 21 shows the maximum portion 1110 of the piston 1804 aligned with the slide member 1802 so that the slide member 1802 can assume its maximum extended state. In this state, slide member 1802 extends sufficiently to allow contact between second stepped contact surface 1904 of slide member 1802 and contact surface 1906 of lever arm 408 . The illustrated switched finger follower, configured in this manner, has an applied motion below the second level (i.e., the motion required to bring contact surface 1906 into contact with second stepped contact surface 1904). 21 loses less motion), but transmits applied motion above the second level, where the second level in FIG. 21 is lower than the first level in the embodiment of FIG. For example, in this mode of operation, the switching finger follower can transmit relatively low valve lift such as brake or other auxiliary valve events, as well as relatively high valve lift such as main event lift.

FIG. 22 illustrates that the slide member 2202 includes an angled contact surface 2206 and the lever arm 408 has an arcuate contact surface 2206, eg, in a manner substantially similar to the embodiments shown in FIGS. 4-10. A second implementation of a 3-position switching finger follower with face 2208 is shown. FIG. 22 shows the slide member 2202 and the transverse bores of the piston 1804 . Further, unlike the embodiment of FIGS. 19-21, no biasing mechanism is required to bias the slide member 2202 away from the lever arm to its maximum retracted condition for reasons explained below.

FIG. 22 particularly shows when intermediate diameter portion 1808 of piston 1804 aligns with slide member 2202 such that slide member 2202 extends from the longitudinal bore greater than its maximum retraction and less than its maximum extension. indicates As a result, lever arm contact surface 2208 engages slide member contact surface 2206 at a relatively low point on slide member contact surface 2206 . Similar to the embodiment shown in FIG. 20, the switching finger follower shown, configured in this manner, provides for applied motion below a first level (i.e., lever arm contact surface 2208 to slide member contact surface 2208). 2206), but transmits applied motion above the first level. For example, in this mode of operation, a switching finger follower may transmit relatively high valve lift such as main event lift, but lose relatively low lift such as braking or other auxiliary valve events.

On the other hand, when the minimum diameter portion 1806 of the piston 1804 is aligned with the slide member 2202, the slide member adopts its maximum retraction state such that the lever arm contact surface 2208 never engages the slide member contact surface 2206, 19, thereby allowing the lever arm 408 to lose the maximum amount of applied valve actuation motion. Further, when maximum diameter portion 1110 of piston 1804 is aligned with slide member 2202, the slide member reaches its maximum extension such that lever arm contact surface 2208 engages a relatively high point on slide member contact surface 2206. 21, which allows lever arm 408 to transmit relatively low levels of valve actuation motion, similar to the embodiment of FIG. Given the angled nature of slide member contacting surface 2206 and the arcuate nature of lever arm contacting surface 2208, any contact between slide member contacting surface 2206 and lever arm contacting surface 2208 will essentially cause slide member 2202 is biased to retract into its longitudinal bore. As a result, unlike the embodiment of Figures 19-21, no separate biasing mechanism is required to bias the slide member against its longitudinal aperture. 19-21, but similar to the embodiment of FIGS. 4-14, the configuration of slide member contact surface 2206 and lever arm contact surface 2208 in FIG. It substantially avoids the possibility of false or incomplete engagement.

FIG. 23 shows an embodiment in which a three-position slide member 2308 is incorporated into valve mechanism components other than finger followers. For example, valve mechanism component 2302 may comprise a central pivot type rocker arm or valve bridge. As shown, the actuator piston 2304 is disposed within a vertical bore 2303 formed in the valve mechanism component. A hydraulic channel 2306 is provided in fluid communication with vertical bore 2303 . In one embodiment, hydraulic channel 2306 supplies unchecked low pressure hydraulic fluid to vertical bore 2303 such that actuator piston 2304 is constantly biased out of vertical bore 2304 . As further shown, valve mechanism component 2302 includes horizontal bore 2307 intersecting vertical bore 2303 . As shown, slide member 2308 (similar to slide member 1802 shown in FIGS. 19-21) is horizontal such that a stepped contact surface of slide member 2308 may engage end 2305 of actuator piston 2304. Disposed within hole 2307 . A piston 2310 (similar to piston 1804 shown in FIG. 18) is provided to control the extension/retraction of slide member 2308 in substantially the same manner as described above with respect to FIGS. 18-22.

When actuator piston 2304 is placed under load (eg, as in the case of a valve opening actuation motion applied to valve mechanism component 2302), hydraulic fluid in vertical bore 2303 flows back into hydraulic channel 2306, which This allows actuator piston 2304 to retract into vertical bore 2303 until end 2305 of actuator piston 2304 contacts one of the stepped surfaces of slide member 2308 or bottoms vertical bore 2303 . In this latter case, i.e., if slide member 2308 is positioned to avoid contact with actuator piston 2304 (or to contact actuator piston 2304 only at the step of the lowest contact surface), then this is the case. If the stroke length of the actuator piston 2304 provided at the end is greater than the maximum valve actuation motion available, all such valve actuation motion is lost. Conversely, if the slide member is positioned such that one of the steps of the higher contact surface engages the end 2305 of the actuator piston, the stroke length of the actuator piston 2304 can be provided with varying degrees of lost motion. are restricted accordingly.

Although certain preferred embodiments have been shown and described, those skilled in the art will recognize that changes and modifications can be made without departing from the teachings of the invention. Accordingly, any and all modifications, variations, or equivalents of the above teachings are considered to be within the basic underlying principles disclosed above and claimed herein. For example, although slide member 502 is described as operating under control of mechanical interaction with in turn hydraulically controlled piston 504, it is understood that other configurations for controlling slide member 502 may be employed. understood. For example, the slide member 502 may be biased to its unlocked or off state by a resilient element, and the hydraulic passageway may be connected to the hole in which the slide member 502 resides, resulting in the application of hydraulic fluid to the passageway. extends the slide member 502 to its locked or on state, while a locked amount of hydraulic fluid in the bore of the slide member maintains the slide member 502 in its extended position. As another example, although the lever arm contact surface 508 is shown as having an arcuate shape, this is not a requirement and other surface configurations, such as angled, semi-circular, etc., can be employed as well. . Further, the configuration of the body 402 and lever arm 408 can be reversed, i.e., the central body is provided with an outer movable arm that is replaced by one or more similarly configured sliding members as described above. It is understood that it can be placed in an unlocked/off state or a locked/on state using . In this same vein, slide member 502 is not deployed within body 402 , but instead within lever arm 408 such that slide member contact surface 506 interacts with another contact surface on body 402 . can be deployed in It is also understood that the multiple modes of operation resulting from the embodiment of FIGS. 18-22 can be expanded to four or more states by using additional intermediate diameter portions of piston 1804. It is understood that in those embodiments where the slide member includes multiple stepped contact surfaces, the single slide member can be replaced with separate slide members that engage the lever arm at different locations.

FIG. 24 shows lost motion profiles for an exemplary finger follower and an exemplary engine operating mode that may correspond to the three positions or states of the three position finger follower, as described above. The curve portion represents the relative stroke length of an exemplary three-state finger follower, where the stroke length is the range of cam (motion source) motion that can be absorbed by the finger follower before it transmits the cam motion to the valve. is. In this illustration, stroke length (y-axis) is related to position (x-axis) of slide member 1802 (FIG. 19) or 2308 (FIG. 23). A first state, represented by curvilinear portion 2402 and corresponding first stroke length when slide member 1802 is in the position shown in FIG. Lost Motion Brake (LMB) motion can be transmitted. A second state, represented by curve portion 2406 and a corresponding second stroke length greater than the first stroke length, absorbs a second range of motion greater than the first absorbed range of motion and provides EEVO motion. can be transmitted to the valve. A third state, represented by curve portion 2408 and a third stroke length greater than the first and second stroke lengths, absorbs a third range of motion greater than the first and second ranges of motion, causing the valve to May transmit principal event (ME) motion.

With additional reference to FIG. 25, this figure further illustrates how camming motion can be lost (or transferred) to the valve by an exemplary finger follower. Cam profile 2502 may correspond to a cam similar to cam 1920 shown in FIG. Profiles 2502 may include primary event lift profile 2522 , first secondary lift profile 2524 , and second secondary lift profile 2526 . Examples of the range of motion transferred (lost) by the finger follower in three different states are denoted R1, R2, and R3. In this figure, the first state of the finger follower is represented by a line coinciding with the x-axis and the range of motion or stroke length (R1, zero in this case) absorbed by the finger follower. That is, in this state all motion is transmitted by the finger followers. The (long/short) dashed lines represent the second state of the finger follower and the corresponding absorbed second range of motion or stroke length (R2). As can be seen, in this condition the motion of auxiliary lobes 2524 and 526 may be hidden (lost) and only the motion of main event lobe 2522 is transmitted. The upper dashed line represents the third state of the finger follower and the third range of absorbed motion or stroke length (R3). In this state, the central peak portion of main event profile 2522 may be transmitted. As will be appreciated, the cam profiles described above with reference to FIGS. 24 and 25 are merely examples and may be implemented in other configurations and using other mechanisms without departing from the scope of the present disclosure.

Specifically from FIG. 25, for example, the step increase in step between stepped contact surfaces 1902 and 1904 in FIG. It will be appreciated that the steps may be different, as represented by the difference in R2, the difference between R2 and R1. That is, the heights of the first step and the second step may be different and not necessarily the same.

Additionally, it will be appreciated that the various engine operating modes achieved by exemplary implementations according to the present disclosure can be configured with appropriate variations in the height and number of available cam lobes. For example, cylinder deactivation (CDA) may be implemented as one of the operating modes, in which case even the main event motion may be lost. Referring back to FIG. 24, in such implementations, CDA/primary event/auxiliary event motion may be used to replace the LMB/EEVO/ME modes shown in FIG. More specifically, auxiliary valve motion may occur when operating in the third portion 2408, main event exhaust motion may occur in the second portion 2406, and auxiliary motion may be added in the first plateau 2402. (Lost motion brake/LIVC/EEVO, etc.).

FIG. 26 illustrates example method steps that may be accomplished in accordance with aspects of the present disclosure. At 2602 , the finger follower is configured in a first state/position in which the slide member 1802 (eg FIGS. 18 and 19) is moved to its leftmost position and the finger follower does not transmit lift from cam 1920 . At 2604, the engine operates in cylinder deactivation mode as all motion from the cam lobes is absorbed by the followers. At 2606, the finger follower may be configured to a second state/position in which the slide member 1802 is shifted rightward (FIG. 19) to a second position (FIG. 20) such that the finger follower is cammed. to transmit a second range of motion from At 2608, the engine operates in the main event positive power operating mode. At 2610, the finger follower may be configured to a third state/position, in which slide member 1802 is shifted further rightward (FIG. 19) to a third position (FIG. 21). In step 2612, the engine operates in an assist mode such as lost motion braking, late intake valve closing, or early exhaust valve opening.

FIG. 27 illustrates another exemplary method that can be accomplished according to aspects of this disclosure. At 2702 the finger follower is configured in a first state/position in which the slide member 1802 (e.g., FIGS. 18 and 19) is moved to its leftmost position and the finger follower transmits main event lift from cam 1920. be. Thus, the first position in this case corresponds to the valve mechanism component (finger follower) that transmits only the highest lift (ie main event) profile at the motion source. At 2706, the finger follower may be configured to a second state/position in which the slide member 1802 is shifted rightward (FIG. 19) to a second position (FIG. 20) such that the finger follower is cammed. to transmit a second range of motion from At 2608, the engine operates in EEVO operation. At 2710, the finger follower may be configured to a third state/position, in which slide member 1802 is shifted further rightward (FIG. 19) to a third position (FIG. 21). At step 2712, the engine operates in lost motion braking mode.

Although the implementation has been described with reference to specific exemplary embodiments, various modifications may be made without departing from the broader spirit and scope of the invention as set forth in the claims. and modifications may be made to these embodiments. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims (22)

A method of controlling movement of at least one valve of an internal combustion engine using a valve mechanism component disposed between a motion source and a motion receiving component, said valve mechanism component comprising: a body; a lever adapted to pivot with respect to the body; and an adjustable support assembly for providing selective support to the lever, the adjustable support assembly engaging the lever. wherein the adjustable support assembly further includes an actuation piston adapted to move within a bore in the moveable latch, the valve mechanism component controlling actuation of the actuation piston; configured to operate in at least two operating states by the method comprising:
moving the actuating piston within the bore to position the movable latch in a first latched position relative to the lever, thereby causing the valve mechanism component to move through a first range of motion from the source of motion; configuring the valve mechanism component to operate in a first of the at least two operating states that communicates to a receiving component;
operating the engine in a first mode of operation when the valve mechanism component is in the first state;
moving the actuating piston within the bore to position the movable latch in a second latched position relative to the lever, thereby moving the valve mechanism component from the motion source to the motion receiving component in a second position; configuring the valve mechanism component to operate in a second of the at least two operating states that conveys a range of motion of
operating the engine in a second mode of operation when the valve mechanism component is in the second state. 2. The method of claim 1, wherein the first range of motion of the valve mechanism component is a range of motion such that no motion is transmitted from the motion source, and the first operating mode is a cylinder deactivation mode. The motion source is configured to provide primary event motion to the at least one valve, and the second range of motion is such that the primary event motion is transmitted from the motion source to the motion receiving component. 2. The method of claim 1, which is a range of motion. configuring the valve mechanism component to operate in a third of the at least two operating states, wherein the valve mechanism component transfers a third range of motion from the motion source to the motion receiving component; and
2. The method of claim 1, further comprising operating the engine in a third mode of operation when the valve mechanism component is in the third state. The motion source is configured to provide assisted motion to the at least one valve, and the third range of motion is a range of motion such that the assisted motion is transferred from the motion source to the motion receiving component. 5. The method of claim 4, wherein 6. The method of claim 5, wherein the assist motion facilitates lost motion braking. 6. The method of claim 5, wherein the assist movement facilitates early opening of the exhaust valve. 6. The method of claim 5, wherein the assist movement facilitates late closing of the intake valve. The motion source is configured to provide a lost motion brake to the at least one valve, and the first range of motion is such that the lost motion brake is transmitted from the motion source to the motion receiving component. 2. The method of claim 1, which is a range of motion. The motion source is configured to provide early exhaust valve opening motion, and the second range of motion is such that the early exhaust valve opening motion is transferred from the motion source to the motion receiving component. 2. The method of claim 1, wherein configuring the valve mechanism component to operate in a third of the at least two operating states, wherein the valve mechanism component transfers a third range of motion from the motion source to the motion receiving component; and
operating the engine in a third mode of operation when the valve mechanism component is in a third state;
The motion source is configured to provide primary event motion to the at least one valve, and the third range of motion is such that the primary event motion is transmitted from the motion source to the motion receiving component. 2. The method of claim 1, wherein the range of motion. Configuring the valve mechanism component to operate in the first condition moves the movable latch within the adjustable support assembly by engaging the latch with a conical surface on the actuating piston. 2. The method of claim 1, further comprising moving. 13. The latch of claim 12, wherein the latch is adapted to move in a direction of latch movement, and wherein moving the movable latch further comprises moving the actuation piston in a direction perpendicular to the direction of latch movement. Method. 14. The method of claim 13, wherein moving the actuation piston further comprises hydraulically actuating the actuation piston. Configuring the valve mechanism component to operate in the first state, the second state, and the third state further includes moving the actuation piston in a direction perpendicular to the direction of latch movement. A method according to claim 4. 2. The method of claim 1, wherein configuring the valve mechanism component to operate in the first state further comprises supporting the lever with a stepped engagement surface on the movable latch. . A method of controlling movement of at least one valve of an internal combustion engine using a valve mechanism component disposed between a motion source and a motion receiving component, said valve mechanism component comprising: a body; a lever pivotally mounted to the body for movement in a lever pivoting direction relative to the body; and an adjustable support assembly for providing selective support to the lever ; A possible support assembly includes a movable latch adapted to support the lever in at least two positions, the adjustable support assembly moving in a direction substantially perpendicular to the lever pivoting direction; and an actuating piston adapted to support the movable latch in the at least two positions, the valve mechanism component configured to operate in at least two operating states by movement of the movable latch. , the method is
moving the actuating piston in a direction of actuating piston movement substantially perpendicular to the direction of latch movement to move the movable latch to a first latched position relative to the lever in a direction of latch movement; configuring the valve mechanism component to operate in a first of the at least two operating states, wherein the valve mechanism component transmits a first range of motion from the motion source to the motion receiving component; and
operating the engine in a first mode of operation when the valve mechanism component is in the first state;
moving the movable latch relative to the lever to a second latched position whereby the valve mechanism component transmits a second range of motion from the motion source to the motion receiving component; configuring the valve mechanism component to operate in a second one of operating states;
operating the engine in a second mode of operation when the valve mechanism component is in the second state. configuring the valve mechanism component to operate in a third of the at least two operating states, wherein the valve mechanism component transfers a third range of motion from the motion source to the motion receiving component; and
18. The method of claim 17, further comprising operating the engine in a third mode of operation when the valve mechanism component is in the third state. The motion source is configured to provide assisted motion to the at least one valve, and the third range of motion is a range of motion such that the assisted motion is transferred from the motion source to the motion receiving component. , thereby facilitating one or more of lost motion braking, early exhaust valve opening, and delayed intake valve closing. When the valve mechanism component operates in the first state and the second state, the downward pivoting of the lever causes the first stepped engagement surface of the movable latch and the second stepped engagement surface of the movable latch to move toward each other. 18. The method of claim 17, wherein the stepped engagement surfaces of the . A method of controlling movement of at least one valve of an internal combustion engine using a valve mechanism component disposed between a motion source and a motion receiving component, said valve mechanism component comprising: a body; a lever adapted to pivot with respect to the body; and an adjustable support assembly for providing selective support to the lever, the adjustable support assembly engaging the lever. wherein the adjustable support assembly further includes an actuation piston adapted to move within a bore in the moveable latch, the valve mechanism component controlling actuation of the actuation piston; configured to operate in at least two operating states by the method comprising:
moving the actuating piston within the bore to position the movable latch in a first latched position relative to the lever, thereby operating in a first of the at least two operating states; configuring the valve mechanism components;
operating the engine in a first mode of operation when the valve mechanism component is in the first state;
moving the actuating piston within the bore to position the movable latch in a second latched position relative to the lever, thereby operating in a second of the at least two operating states; configuring the valve mechanism components;
operating the engine in a second mode of operation when the valve mechanism component is in the second state. 22. The method of claim 21, wherein the first mode of operation is a cylinder inactive mode.

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