EP0498682A1 - Ventilsteuervorrichtung zum Ausschalten für eine Brennkraftmaschine - Google Patents

Ventilsteuervorrichtung zum Ausschalten für eine Brennkraftmaschine Download PDF

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Publication number
EP0498682A1
EP0498682A1 EP92400025A EP92400025A EP0498682A1 EP 0498682 A1 EP0498682 A1 EP 0498682A1 EP 92400025 A EP92400025 A EP 92400025A EP 92400025 A EP92400025 A EP 92400025A EP 0498682 A1 EP0498682 A1 EP 0498682A1
Authority
EP
European Patent Office
Prior art keywords
liquid
volume
pistons
control device
hydraulic
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP92400025A
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English (en)
French (fr)
Inventor
Patrick Gastaldi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Renault SAS
Regie Nationale des Usines Renault
Original Assignee
Renault SAS
Regie Nationale des Usines Renault
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Renault SAS, Regie Nationale des Usines Renault filed Critical Renault SAS
Publication of EP0498682A1 publication Critical patent/EP0498682A1/de
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
    • F01L1/02—Valve drive
    • F01L1/024—Belt drive
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
    • F01L13/0005—Deactivating valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
    • F01L9/10—Valve-gear or valve arrangements actuated non-mechanically by fluid means, e.g. hydraulic
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
    • F01L9/10—Valve-gear or valve arrangements actuated non-mechanically by fluid means, e.g. hydraulic
    • F01L9/11—Valve-gear or valve arrangements actuated non-mechanically by fluid means, e.g. hydraulic in which the action of a cam is being transmitted to a valve by a liquid column
    • F01L9/12—Valve-gear or valve arrangements actuated non-mechanically by fluid means, e.g. hydraulic in which the action of a cam is being transmitted to a valve by a liquid column with a liquid chamber between a piston actuated by a cam and a piston acting on a valve stem
    • F01L9/14—Valve-gear or valve arrangements actuated non-mechanically by fluid means, e.g. hydraulic in which the action of a cam is being transmitted to a valve by a liquid column with a liquid chamber between a piston actuated by a cam and a piston acting on a valve stem the volume of the chamber being variable, e.g. for varying the lift or the timing of a valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
    • F01L1/34—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
    • F01L1/344—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear
    • F01L1/3442—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear using hydraulic chambers with variable volume to transmit the rotating force
    • F01L2001/34423—Details relating to the hydraulic feeding circuit
    • F01L2001/34446—Fluid accumulators for the feeding circuit

Definitions

  • the present invention relates to a valve control device with a shutdown function, in particular for a multi-valve internal combustion engine.
  • a first solution is to have a variable valve lift depending on the speed and the engine load.
  • Many devices have been developed, mention may be made of variable profile rotary cams carried by a shaft sliding along its axis as a function of an engine operating parameter; or alternatively two cams carried respectively by two parallel camshafts, the selective use of one of the cams being effected by engagement of one of the shafts or by tilting of a support of the two shafts.
  • the disadvantage of these devices is their great complexity and their significant additional cost.
  • 2,546,968 relating to a mechanism for operating valves with a shutdown function for an internal combustion engine, describes a device in which first and second rocker arms, having respective arms abutting against the upper ends of the intake or exhaust valve fitted , are articulated on a common carrier axis fixed on the body of the engine and whose geometric axis is perpendicular to the directions of movement of the valves;
  • the first rocker has a bore forming a cylinder which opens towards the second rocker to carry a plunger in its interior while the second rocker has a guide bore opening towards the first rocker so that the plunger fits there;
  • a hydraulic operating chamber defined between the bottom of the cylinder bore and the rear end of the plunger is connected to a source of pressurized oil through a hydraulic permutation valve intended to permute the sending and non-sending of 'oil under pressure in the operating chamber; and one or the other of the first and second rocker arms has a cam feeler intended to slide against a cam arranged to rotate according to
  • the object of the present invention is to overcome these drawbacks by providing a valve control device of limited size, which can be stopped in an extremely short time, of the order of ten milliseconds, does not interfere with the controls of the other valves, which can be used with direct drive distribution such as rocker distributions: rockers, latches, etc. and allowing more to catch the operating clearances; such an extremely flexible use device makes it possible to pass from a four-valve operation to a two-valve operation or else to pass from a four-cylinder operation to a three-cylinder operation by equipping all the valves with a cylinder.
  • the present invention relates to a valve control device with a shutdown function, for internal combustion engines, comprising a hydraulic tappet capable of transmitting or not the thrust of a cam, carried by a camshaft, to a valve stem against elastic return means, this hydraulic tappet comprising two pistons separated by a volume of liquid, in particular oil.
  • the valve control device comprises distribution means suitable for communicating the volume, comprised between the two pistons, either with means for connection to a source of pressurized liquid, or with means for connection with a liquid discharge tank, these distribution means being controlled by a high liquid source pressure depending on engine speed and / or load.
  • the distribution means comprise a first hydraulic distributor, comprising in particular a movable drawer in its housing, having at least one fluid passage duct, this drawer being able to occupy two limit positions, a first limit position wherein the drawer connects the volume between the two pistons and the means of connection to a source of pressurized liquid while all communication between said volume and the means of connection to a liquid discharge tank is cut and a second limit position in which the slide valve connects said volume and the means of connection to a liquid discharge tank while all communication between said volume and the means of connection to a source of pressurized liquid is cut off and a second hydraulic distributor allowing to operate said first distributor from a source of liquid high pressure depending on engine speed and / or load.
  • a first hydraulic distributor comprising in particular a movable drawer in its housing, having at least one fluid passage duct, this drawer being able to occupy two limit positions, a first limit position wherein the drawer connects the volume between the two pistons and the means of connection to a source of pressurized liquid while all communication between
  • the drawer of the first hydraulic distributor defines in its housing two chambers, a first chamber, in which are arranged elastic pressure means which act on the drawer, and a second chamber forming part of said means of connections to a liquid discharge tank; these chambers are connected, one to a high liquid source pressure, the other to a liquid discharge tank and vice versa, via the second hydraulic distributor of the type: piloted with four ways and two positions.
  • the volume between the two pistons is limited axially by the two pistons and transversely by a bore, slidingly receiving the two pistons, in which open at least one recess which also communicates with the housing of the first hydraulic distributor, the axial length of the recess being sufficient to ensure permanent communication between said volume and said recess.
  • the means for connecting to a source of pressurized liquid notably comprise a cavity forming a hydraulic shock absorber, this cavity opening into the housing of said first distributor, means forming a valve and a pressure reducing valve ensuring regulation of the pressure of the liquid supplying said cavity.
  • said movable drawer consists of a substantially cylindrical sheath, coaxial with the hydraulic plunger, comprising an enlarged end forming an operating piston, this sheath having at least one lumen forming a conduit for the passage of fluid.
  • the bore in which the two pistons form stop means intended to cooperate with shoulders carried by the two pistons so as to limit the relative movement of these pistons and in particular to confine said volume inside said bore.
  • the piston of the hydraulic pusher intended to come into contact with the operating cam is subjected to the action of elastic pressure means capable of moving this piston away from the cam.
  • the source of high pressure liquid comprises in particular a supply pump, an accumulator and a discharge device of the contactor-circuit breaker type.
  • control of the distribution means is integrated into the ignition control of the engine according to a predetermined map as a function of the speed and of the load, the response time of said means being taken into account by the calculator.
  • the invention also relates to a hydraulic tappet comprising two pistons separated by a volume of liquid, in particular oil, arranged for a valve control device with a shutdown function according to the invention.
  • FIG. 1 one can see a device for controlling an intake or exhaust valve of an internal combustion engine, presented in the particular case of a mode of distribution. direct attack.
  • the control device comprises a hydraulic pusher 1 intended to transmit the thrust from a cam 52 carried by a camshaft 5 to an intake or exhaust valve 4, of an internal combustion engine of which only the parts of interest the invention have been shown, against elastic return means formed by a helical spring 31.
  • the spring 31 works in compression and tends to return the valve 4 to its closed position, which corresponds, in the representation of FIG. 1, to an upward movement of the valve stem 42.
  • the hydraulic pusher 1 comprises two pistons 2, 3 separated by a volume or cavity 6 filled with liquid, in particular oil.
  • One of the pistons, namely the piston 2 is intended to come into contact with the cam 52 while the other piston 3 is in permanent abutment against the stem of the valve 42 due to the thrust of the spring 31.
  • the pistons 2 and 3 have their ends, respectively lower and upper, slidably mounted in a housing 64 of the cylinder head 99.
  • the volume 6 is thus limited axially by the two pistons and transversely by this bore 64.
  • the piston 2 which is substantially cylindrical, carries an upper pad 26 intended to rub on the cam 52; it has a circumferential shoulder 25 on which elastic pressure means bear, formed by a helical spring 21. These means 21, also bearing on the cylinder head 99 by means of a crimped barye 22, tend to spread the piston apart 2 of the cam 52 as well as forcing the piston 2 towards the piston 3.
  • the substantially cylindrical piston 3 is blind; it has a shoulder 35 intended to cooperate with a recess of the bore 64, on its lower end support elastic pressure means, formed by a helical spring 31. These means also bearing on the cylinder head tend to force the piston 3 towards piston 2.
  • a hydraulic distributor 70 intended to control the volume of liquid 6 comprised between the two pistons 2 and 3.
  • This hydraulic distributor comprises a housing 75 of revolution extending around the pusher 1 and in which slides axially at pusher 1 a cylindrical sheath 7.
  • the sleeve 7 has an enlarged end which forms an operating piston 76 of the sleeve 7.
  • the piston 76 defines in the housing 75 two pressure chambers, a first chamber 9 extending under the piston 76 and a second chamber 8 disposed above of the piston 76.
  • the underside of the piston 76 is subjected to the action of elastic pushing means in the form of a helical spring 71 also bearing in the bottom of the housing 75.
  • the sheath has two slots 72,73 arranged at different levels which allow the communication of the volume 6 with respectively means of connection to a source of pressurized liquid and means of connection to a discharge tank.
  • the volume 6 is placed in communication with the housing 75 of the distributor 70 by two recesses 62, 63 formed in the body of the cylinder head 99 and opening both into the bore 64 and into the housing 75; the axial length of these two recesses is sufficient to ensure permanent communication between these recesses 62, 63 and the volume 6.
  • the housing 75 communicates with a cavity of pressurized liquid 10 supplied by a pressure source which can be for example the oil pump of the lubrication circuit, a reduction gear pressure 11 is interposed on the hydraulic circuit in order to regulate the pressure of the liquid to a predetermined value of approximately 10 bars.
  • a non-return ball valve 61 is also disposed between the reduction gear 11 and the cavity 10.
  • the displacement of the sheath 7 of the distributor 70 is operated by a second distributor 12 which controls the pressure of the chambers 8 and 9.
  • This distributor 12 is a hydraulic distributor controlled with four channels and two positions. It makes it possible to put the chambers 8 and 9 into communication with a source of liquid under high pressure 20, around 100 bars, or with a liquid discharge tank 13 and vice versa.
  • the source of high pressure liquid 20 can be constituted, as shown diagrammatically, by a hydraulic pump 14, a contactor-circuit breaker 15 and a pressure accumulator 16.
  • the valve control device 4 is in operation or in clutched mode, as shown in FIG. 1.
  • the distributor 12 is positioned so as to send the high pressure into the cavity 8 while the cavity 9 is placed in communication with the liquid reservoir. 13.
  • the distributor 70 thus supplied, the drawer or sleeve 7 is kept locked in the lower limit position, its end forming a piston 76 bearing against the shoulder 77, the spring 71 being compressed in the chamber 9.
  • the volume 6 is filled with and is in communication with the auxiliary cavity 10 through the orifice 72 formed in the sleeve 7 which places the recess 62 in communication with the cavity 10.
  • This cavity 10 supplied with pressurized oil via the oil reducer serves to dampen the oscillations of the pressure due to the compressibility of the oil during movement of the pusher 1.
  • valve control device 4 conventionally operates with a hydraulic pusher 1 with backlash adjustment.
  • the pusher 1 When the pusher 1 is at rest, valve 4 closed, the oil of the lubrication system under pressure, coming from of the pressure reducer 11 fills the device, namely the cavity 10, the chamber 6 and the adjacent recesses 62, 63.
  • the cam 52 acts on the pusher 1, a ball valve 61 traps this volume of oil whose incompressibility secures the complete device: the pusher 1 can then transmit the thrust from the cam 52 to the valve stem 42.
  • the distributor 12 is operated so as to send the high pressure into the chamber 9 of the distributor 70 while simultaneously the chamber 8 is placed in communication with the discharge tank 13.
  • the imbalance of the pressures exerted on the faces of the piston 76 causes the sleeve 7 to rise up until it comes into abutment and stops in the upper limit position.
  • the spring 71 locks the drawer or sleeve 7 in the high position and prevents the latter does not vibrate because of the play existing between the pusher and its stop.
  • the volume 6 is placed in communication with the chamber 8 through the lumen 73 while all communication with the cavity 10 is cut off.
  • the piston 2 is pushed back towards the piston 3, the oil contained in the volume 6 is then driven into the chamber towards the discharge tank until the piston 2 comes in contact with the piston 3 and remains there under the action of the spring 21.
  • the cam 52 can no longer reach the piston 2, the piston 3 remains stationary, its shoulder 35 bearing against the bore 64 under the action of the spring 31.
  • the valve 4 therefore also remains stationary in abutment on its seat.
  • the high pressure pump 14 charges the accumulator 16 at a pressure of approximately 100 bars, necessary for operating distributors 12 and 70, and therefore a disengagement and a clutch of the control device, extremely fast.
  • the hydraulic circuit breaker 15 allows the pump 14 to deliver without pressure, therefore consuming very little during the rest periods.
  • the control of the distributor 12 which controls the operation of the valve control device can be carried out mechanically and / or electrically as a function of one or more engine operating parameters.
  • a particularly interesting solution is the integration into the already existing ignition computer of the engine according to a specific map, three dimensions for example depending on the speed and the load, the computer having to take into account the response times of distributors 12 and 70 .
  • a valve control device has therefore been produced according to the invention for an internal combustion engine with a shutdown function which allows extremely fast clutch and disengage speeds and this in a relatively simple manner.
  • the invention includes all the technical equivalents of the means described and their combinations if these are carried out according to the spirit. So it is possible to use as a drawer for the dispenser 70 a folder rotating having a light and being able to rotate by means of a stepping motor by means of a belt.
EP92400025A 1991-01-08 1992-01-07 Ventilsteuervorrichtung zum Ausschalten für eine Brennkraftmaschine Withdrawn EP0498682A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9100141 1991-01-08
FR9100141A FR2671377A1 (fr) 1991-01-08 1991-01-08 Dispositif de commande de soupape a fonction de mise a l'arret pour moteur a combustion interne.

Publications (1)

Publication Number Publication Date
EP0498682A1 true EP0498682A1 (de) 1992-08-12

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EP92400025A Withdrawn EP0498682A1 (de) 1991-01-08 1992-01-07 Ventilsteuervorrichtung zum Ausschalten für eine Brennkraftmaschine

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FR (1) FR2671377A1 (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1493945A1 (de) * 2003-07-02 2005-01-05 The Channel Tunnel Group Limited Vorrichtung zum Umwandlen einer Winkelbewegung in einer linearen Bewegung
WO2006042785A1 (de) * 2004-10-15 2006-04-27 Robert Bosch Gmbh Verfahren zum betreiben einer brennkraftmaschine
EP3156619A1 (de) * 2015-10-13 2017-04-19 C.R.F. Società Consortile per Azioni System und verfahren zur variablen betätigung eines ventils einer brennkraftmaschine mit einer vorrichtung zur dämpfung von druckschwingungen
WO2018065011A1 (de) * 2016-10-05 2018-04-12 Schaeffler Technologies AG & Co. KG Hydraulische gaswechselventiltrieb mit einem an einem druckraum über eine drossel angeschlossenen dämpferraum
CN110005498A (zh) * 2019-05-15 2019-07-12 杰锋汽车动力系统股份有限公司 一种用于内燃机的两级可变气门升程机构

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110615516A (zh) * 2019-09-19 2019-12-27 河南盛润水处理技术有限公司 一种用于处理金属废水的沉降室内壁清理设备

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4153016A (en) * 1977-04-28 1979-05-08 Hausknecht Louis A Valve control system
GB2017861A (en) * 1978-04-04 1979-10-10 Turner D Means for selectively transmitting drive
WO1990014505A1 (fr) * 1989-05-25 1990-11-29 William Bulens Dispositif permettant une distribution a diagramme et levee variables des soupapes pour moteur d'automobile

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59170415A (ja) * 1983-03-17 1984-09-26 Nissan Motor Co Ltd 内燃機関
JPS61187506A (ja) * 1985-02-15 1986-08-21 Odai Tekko Kk 内燃機関における休止機能付動弁機構

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4153016A (en) * 1977-04-28 1979-05-08 Hausknecht Louis A Valve control system
GB2017861A (en) * 1978-04-04 1979-10-10 Turner D Means for selectively transmitting drive
WO1990014505A1 (fr) * 1989-05-25 1990-11-29 William Bulens Dispositif permettant une distribution a diagramme et levee variables des soupapes pour moteur d'automobile

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 11, no. 10 (M-552)(2457) 10 Janvier 1987 & JP-A-61 187 506 ( ODAI TENKO KK ) 21 Août 1986 *
PATENT ABSTRACTS OF JAPAN vol. 9, no. 25 (M-355)(1748) 2 Février 1985 & JP-A-59 170 415 ( NISSAN JIDOSHA KK ) 26 Septembre 1984 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1493945A1 (de) * 2003-07-02 2005-01-05 The Channel Tunnel Group Limited Vorrichtung zum Umwandlen einer Winkelbewegung in einer linearen Bewegung
FR2857074A1 (fr) * 2003-07-02 2005-01-07 Channel Tunnel Group Ltd Dispositif de conversion d'un mouvement angulaire en mouvement lineaire
WO2006042785A1 (de) * 2004-10-15 2006-04-27 Robert Bosch Gmbh Verfahren zum betreiben einer brennkraftmaschine
EP3156619A1 (de) * 2015-10-13 2017-04-19 C.R.F. Società Consortile per Azioni System und verfahren zur variablen betätigung eines ventils einer brennkraftmaschine mit einer vorrichtung zur dämpfung von druckschwingungen
US10156163B2 (en) 2015-10-13 2018-12-18 C.R.F. Societa Consortile Per Azioni System and method for variable actuation of a valve of an internal-combustion engine, with a device for dampening pressure oscillations
WO2018065011A1 (de) * 2016-10-05 2018-04-12 Schaeffler Technologies AG & Co. KG Hydraulische gaswechselventiltrieb mit einem an einem druckraum über eine drossel angeschlossenen dämpferraum
CN110005498A (zh) * 2019-05-15 2019-07-12 杰锋汽车动力系统股份有限公司 一种用于内燃机的两级可变气门升程机构

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Publication number Publication date
FR2671377A1 (fr) 1992-07-10
FR2671377B1 (de) 1994-12-09

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