Abstract: A return spring is formed using a compression coil spring that is installed so that its axial direction is an up-down direction. The return spring is provided in a high-pressure chamber, and powers a plunger in an upwards direction. A coil diameter of the return spring varies along the axial direction. When the return spring is in a maximally compressed state, an axial direction dimension (up-down direction dimension) is smaller than a dimension that is a thickness of a spring wire multiplied by the number of coil turns. Hence, an overall height of a lash adjuster A can be reduced in comparison to when a return spring with a constant coil diameter over an entire length is used.

Abstract: A sealed lash adjuster (100A) has a plunger (2), and a body (1A) accommodating the plunger. In addition, the sealed lash adjuster (100A) has a first seal member (5) on a sliding portion of the plunger (2), and has a second seal member (30) on a sliding portion of the body (1A) that faces the sliding portion. Specifically, the lash adjuster (100A) has the first seal member (5) on the sliding portion of the plunger (2) and the second seal member (30) on the opposing sliding portion of the body (1A), such that a space K formed between the first seal member (5) and the second seal member (30) expands when the plunger (2) is pressed inward, and the space K contacts when the plunger (2) protrudes outward.

Abstract: A switchable component (1) of a valve train of an internal combustion engine is provided, with a housing (2) in whose borehole (3) an inner element (4) is held so that it can move telescopically. At least one coupling piston (7) guided by an anti-rotation locking device (6) is located in a radial borehole (5) of the inner element (4) in a decoupled case, with a section (10) that is flattened in some areas being provided on the coupling piston on one axial side (9) starting from its outer end (8). The borehole (3) of the housing (2) has a window (11) with a complementary engagement surface (12) against which, in a coupled case, the coupling piston (7) can be displaced with its flattened section (10) when passing through the cam base circle. An edge (13) between the outer end (8) and the flattened section (10) of the coupling piston (7) is provided with a bevel (14) that is a surface section of an ellipsoid whose longitudinal axis runs parallel to the flattened section (10).

Abstract: A hydraulic cam follower (1), such as a roller tappet, is provided. This is used for the actuation of two identically operating gas-exchange valves and should be installed inclined to the direction of the force of gravity. The cam follower (1) comprises a pot-shaped housing (2), whose bottom (3) is provided with a roller as a cam contacting element (4). In the housing (2), two guides (5) extending parallel to the direction of the internal combustion engine are provided, in each of which a pressure piston (6) is arranged so that it can move axially, whose end (7) away from the housing is constructed as a support for contact with a respective tappet pushrod. Each pressure piston (6) encloses a reservoir (11) for hydraulic medium.

Abstract: The liquid is sealed in the lash adjuster so that the volume “V1” of the gas, in the reservoir chamber when the lash adjuster is being produced and the plunger protrudes from the body, is equal to or more than 1.24 times as great as the sum of the volume “Vo1” of the liquid discharged from the high-pressure chamber when the plunger moves downward, and the increase “Vo2” in the volume of the liquid that expands, due to heat, when the temperature of the gas in the reservoir chamber is increased from the production temperature to the maximum use temperature, and the ratio of “V1” to “Vo1+Vo2” is equal to or higher than a ratio, which is derived based on the production temperature and the maximum use temperature, when the inner pressure of the lash adjuster increases by 500 kPa at maximum.

Abstract: A switchable support element (1) comprising a housing (2) in whose bore (4) an axially displaceable pressure piston (7) extends, said support element (1) comprising at least one coupling element (8) for an optional coupling of the pressure piston (7) in its axially extended position relative to the housing (2), said pressure piston (7) being biased in an outward direction from the housing (2) by at least one lost motion spring (9).

Abstract: A deactivation valve lifter includes a lifter body. The lifter body has a first end configured for engaging a cam of an engine and at least one annular pin chamber. A pin housing includes a pin housing bottom. The pin housing bottom defines at least one pin stop aperture and a radially directed pin bore. A deactivation pin assembly is disposed within the pin bore and includes pin members. The pin housing is concentrically disposed within the lifter body. A portion of each pin member may be disposed within the annular pin chamber to thereby selectively couple and decouple the lifter body to the pin housing. A drain aperture defined by the pin housing bottom extends from the pin bore to an outside surface of the pin housing. A stop pin is disposed in the at least one pin stop aperture for limiting the inward motion of the pin members.

Abstract: A hydraulically lashed end pivot rocker arm assembly finds application in high performance valve trains of internal combustion engines. The rocker arm is mounted at one end upon an eccentric bearing assembly and includes a surface for engaging a valve stem at the opposite end and a roller engaged by a camshaft disposed between the ends. The eccentric bearing assembly includes a stub shaft or cylindrical body that is received within a bore in the rocker arm and an eccentric bore which receives an inner shaft which extends along the cylinder head and supports the eccentric bearings and the rocker arm assemblies. The stub shaft or cylindrical body includes an ear or lug which is engaged by a hydraulic lash adjuster disposed parallel to and offset from the vertical plane of motion of the rocker arm.

Abstract: In one aspect, the present disclosure is directed to a tappet assembly for a machine. The assembly may include a tappet body, a pin fixedly mounted in the tappet body, and a substantially cylindrical roller mounted about the pin. The roller may have a substantially cylindrical outer surface with a circumferential dimension and a width dimension, the width dimension being defined by two lateral edges. The roller may be configured to provide rolling contact between the outer surface of the roller and a cam lobe. The outer surface of the roller may be crowned such that at maximum operational loading conditions of the machine a footprint of contact pressure from the cam lobe is spread substantially the full width of outer cylindrical surface of the roller.

Abstract: Proposed is a switchable valvetrain (1) for an internal combustion engine, having a row of rocker arms (2) which extend in the longitudinal direction of a cylinder head, which rocker arms (2) run via a recess (7) on an upper side (6) on a head (8) of a bearing journal (9), which bearing journal (9) is axially moveably arranged in a bore (10) of a carrier (11) which runs above, with piston-like coupling means (12) being provided for selectively coupling the bearing journal (9) to the carrier (11).

Abstract: A switchable valve train member, such as a deactivating valve lash adjuster or a deactivating hydraulic valve lifter, including a pin housing slidably disposed within an axial bore in a body. A transverse bore in the pin housing contains a retractable locking pin that engages a feature in the body including a locking surface whereby the body and the pin housing are locked together for mutual actuation by rotation of a cam lobe. A lash ring at the outer end of the body includes a portion extending into the axial bore that limits the travel of the pin housing within the body and thereby sets the internal mechanical lash in the switchable member. The axial thickness of the lash ring may be varied between assemblies to compensate for manufacturing variation in the components and is secured to the body in any of various configurations.

Abstract: A tappet apparatus cooperates with a valve and a cam. The apparatus includes a case to reciprocate motion of the cam; and a locking unit in the ease, movable between an activated position at which the valve reciprocates motion of the case, and a deactivated position at which the valve is stationary regardless of the motion of the case. The locking unit may include first and second passages in the case; a pin, movable between a first and a second position within the first passage; and a column in the second passage. The pin may be situated in the column when the pin is in the second position. The activated position may be defined by the pin being in the first position, and the deactivated position may be defined by the pin being in the second position.

Abstract: A switchable support element (1) for a valve train of an internal combustion engine, said support element (1) comprising a housing (2) that can be arranged through an outer peripheral wall (3) in a reception of the internal combustion engine and in whose bore (4) an axially movable inner element (6) extends, a head (5) of the inner element (6) protruding beyond an edge (7) of the housing (2), coupling elements (8) being associated to the inner element (6) for a selective coupling of the inner element (6) in an axially extended position of the inner element (6) to the housing (2), and said inner element (6) being biased by at least one lost motion spring (9) in a direction leading out of the housing (2), wherein the coupling elements (8) are at least one slide which, in case of uncoupling, is positioned in a guide (10) of the housing (2) extending in radial or secant direction and which comprises a flattened upper side (12) starting from a radially inner front end (11) of the slide, and this flattened upper si

Abstract: A valve lifter assembly for deactivating a cylinder in an internal combustion engine. The valve lifter assembly is provided with a plunger movably disposed within a bore of a main body member to controllably isolate the cam lift from the rocker arm and valve of the engine. The plunger is normally locked in an extended position to transmit cam lift to reciprocatingly operate the valve. At least one locking pin is moveably disposed within the plunger to engage an inner annular groove of the main body member. Pressurized oil is provided to dislodge the locking pins from the annular groove and allow the plunger to move within the main body member, thereby isolating the cam lift from the rocker arm and valve. The deactivating lifter is preferably disposed within the recess conventionally provided for hydraulic valve lifters.

Abstract: In a cam journal (12A) in which a timing-advance oil passage (12a) and a timing-retard oil passage (12b) are provided as a first oil passage for VVT, an oil passage (102c) for HLA is provided as the second oil passage. The timing-advance oil passage (12a) and the timing-retard oil passage (12b), which are formed on the surface of the intake camshaft (12), are separated from the oil passage (102c) for HLA by a lower cam bearing (202). Thus, it is possible to provide the control oil passages for VVT and the oil supply passage for HLA in one cam journal (12A).

Abstract: A tappet for an internal combustion engine is formed from a high-carbon, bearing grade steel. The high-carbon, bearing grade steel has a relatively high surface fatigue strength that provides the tappet with the ability to absorb a relatively large contact stresses during operation, thereby minimizing the formation of cracks within the tappet. Additionally, the high-carbon steel tappet can be heat treated to provide a substantially uniform hardness, between about 58 Rockwell Hardness C (HRC) and 62 HRC, and a substantially consistent microstructure throughout the tappet, thereby minimizing wear of the tappet during use.

Abstract: A hydraulic lash adjuster (17;61;81) in which the body (19) defines a body bore (39) extending over substantially the entire axial length of the body, thus making it possible to finish the bore (39) by a more accurate process, such as honing. In the FIG. 2 embodiment, there is a cylindrical member (71) disposed in the lower portion of the body bore (39) cooperating to define a leakdown clearance (39,71 S), to isolate side load on the plunger (25) the leakdown. In the FIG. 3 embodiment, there is both the leakdown clearance (23S,39) between the body bore and the plunger (23) and the leakdown clearance (39,71 S) between the body bore and the cylindrical member (71), the leakdown flow rate of FIG. 3 being variable if the body and the cylindrical member (71) comprise dissimilar metals, having different coefficients of thermal expansion.

Abstract: A hydraulic valve lash adjuster with idle stroke function for a valve train of an internal combustion engine, said hydraulic valve lash adjuster comprising a piston (2, 2?, 2?) that is guided for displacement in a piston housing (4) and elastically supported against said housing (4), said piston (2, 2?, 2?) comprising a low pressure chamber (3) that communicates via an axial opening (7) in a piston bottom (8) with a high pressure chamber (5) defined by the piston housing (4) and the piston (2, 2?, 2?), and further comprising a control valve (9, 9?, 9?, 9??) acting between said pressure chambers (3, 5), said control valve (9, 9?, 9?, 9??) comprising a valve closing body (10, 10?, 10?) that can be brought to bear sealingly against a valve seat (15, 15?) that surrounds the axial opening (7) on a piston body undersurface (18) and is received in an element (12, 12?) that limits a closing body stroke (17), and said control valve (9, 9?, 9?, 9??) further comprising a control valve spring (11) that loads the valve cl

Abstract: A hydraulic valve play compensating element for generating valve play compensation for a gas exchange valve in a valve operating mechanism of an internal combustion engine, having a piston housing in which a piston, which is elastically supported against the piston housing via a piston spring, is guided in a movable fashion, in which the piston has a low-pressure space which is connected via an axial opening in a piston head to a high-pressure space which is enclosed by the piston housing, and having a control valve which has at least one control valve closing element which can bear in a seal-forming fashion against a valve seat, the letter surrounding the axial opening on a piston head underside, and comprises a control valve spring which is preloaded in the opening direction, wherein, in the event of a collapsing movement between the piston and the piston housing when the gas exchange valve is actuated, the control valve closing element can be acted on hydraulically in the closing direction by means of a bu

Abstract: A switchable double tappet (1) is provided, especially for a tappet-push rod valve train of an internal combustion engine, with a cylindrical housing (2), which is arranged so that it oscillates via its outer casing (3) in a guide (4) in the internal combustion engine side and which has a bore (5) on the camshaft side, in which an inner element (6) moves axially relative to this borehole, wherein, on one side, a cam contact surface (10) is intrinsic to this inner element on its end projecting past an edge (7) of the borehole (5) or lower head (9) running in the region of the edge (7) and also, on the other side, at least one coupling slide (11) is intrinsic in its interior in the decoupled case, and this coupling slide can be displaced partially for a coupled case in or under a respective catch surface (12) of the housing (2), wherein between an upper head (13) of the inner element (6) facing away from the lower head (9) and a lower side (14) of a crossbar (15) of the housing (2), at least one lost-motion spr

Abstract: A switchable bucket tappet for a valve drive of an internal combustion engine, which has a bucket base body with a ring-shaped base guided by a skirt projecting from the outer edge of the base, in a bore of the engine. A lifting cam acts on the base and a hollow cylindrical extension projects from an inner edge of the base. In the bore, an inner body is axially movable relative to the bucket base body and, formed in the underside of the inner body, is a support for indirect contact with a gas exchange valve. A coupling piston, which has a flattened portion on its upper side, runs in a bore of the inner body and is engaged with a driver surface for full valve lift. A lost motion spring acts between the bucket base body and inner body.

Abstract: A multiple cylinder internal combustion engine having a camshaft-driven valvetrain with a camshaft disposed within an engine block includes at least two intake and/or exhaust valves with a pair of valves operated by a common camshaft lobe and a cam follower. The valvetrain may include independently operable mechanical or hydraulic lash adjusters. The cam follower contacts the common camshaft lobe and at least two pushrods with each pushrod having an associated single plane rocker arm which couples to a fulcrum mounted to the cylinder head to actuate the at least two valves.

Abstract: A valve-deactivation hydraulic valve lifter including a recessed face on the pin housing for making contact with the a crowned surface region of a roller follower. The lifter includes a pin housing that is slidably disposed within an axial bore in a lifter body. Pins for variably locking the pin housing to the lifter body may be disengaged to place the lifter in lost-motion mode by application of engine oil to the outer ends of the pins. A surface of the pin housing, preferably configured as a dished surface, is formed on the bottom end face of the pin housing that approaches the cam-following lifter roller for making contact with the roller follower so as to avoid contacting the roller follower's crowned surface region.

Abstract: A force transmitting device (4) for a valve drive (1) of an internal combustion engine (2) with a hydraulic valve lash compensating device (6) is provided. The force transmitting device (4) has a hollow cylindrical compensating piston (13), which on one end defines a working chamber (35) of the valve lash compensating device (6) and on the other end encloses an internal hydraulic medium reservoir (15) used to supply the working chamber (35). This is connected to a hydraulic medium supply (16) of the internal combustion engine (2) and is protected from a return flow of hydraulic medium in the direction of the hydraulic medium supply (16) by means of a valve plate (26), which can be pressurized and which can move axially, in that the valve plate (26) interacts in a sealing way with an axial annular surface (28) of the compensating piston (13) for a non-pressurized hydraulic medium supply (16).

Abstract: An apparatus and method for automatically adjusting the valve lash of an internal combustion engine is provided. In another aspect of the present invention, a probe is employed for verifying and/or setting valve lash settings in an automated manner. A further aspect of the present invention does not require determination of a zero lash position or reference datum prior to adjusting the valve lash adjusting screw for desired lash.

Abstract: An automatic tappet clearance adjusting device, comprising an adjusting unit adjusting the projected amount of a rocker arm by advancing and retreating an adjust screw to and from the tip of the rocker arm, a pressure setting part electrically controlling the pressure of an air supply source part based on the measurement signals of a primary side pressure sensor measuring the pressure of the air supply source part so that the pressure becomes a specified one, a supply pipeline allowing the air supply source part to communicate with a combustion chamber through a variable orifice, and a control mechanism part controlling the adjusting unit based on measurement signals of a secondary side pressure sensor measuring the pressure of the supply pipeline. The pressure is set to 1.5 kPa by the pressure setting part and the variable orifice.

Abstract: An apparatus and method for automatically adjusting the valve lash of an internal combustion engine is provided. In another aspect of the present invention, a probe is employed for verifying and/or setting valve lash settings in an automated manner. A further aspect of the present invention does not require determination of a zero lash position or reference datum prior to adjusting the valve lash adjusting screw for desired lash.

Abstract: An automatic tappet clearance adjuster comprising a unit for adjusting the projection by advancing/retracting an adjust screw from the forward end of a rocker arm, a section for detecting the torque by rotating the adjust screw, and a control mechanism section for controlling the adjusting unit according to the torque value measured by the torque detecting section. The control mechanism section measures the torque value continuously when a valve is closed by retracting the adjust screw from the open state of the valve. A rotation reference position corresponding to the intersection of a first approximation line and a second approximation line approximating the sections immediately before and after the inflection point of differential value of the torque value is detected as a reference point, and the adjust screw is retracted by a set amount from the reference point.

Abstract: This invention is to provide a tappet clearance adjusting cover coupled with a secondary air valve. The tappet clearance adjusting cover is disposed on a cylinder head of an engine. The secondary air valve includes a recessed element and a cap which jointly form a receiving space receiving therein a one-way valve. The recessed element is provided with an inlet pipe interposed between the cap and the tappet clearance adjusting cover. By disposing the secondary air valve on the tappet clearance adjusting cover and arranging the inlet pipe between the cap and the tappet clearance adjusting cover, with the one-way valve received in the receiving space of the secondary air valve, heat dissipation can be improved while the one-way valve is protected against premature deterioration and carbon deposition caused by a high-temperature exhaust gas from the cylinder head. Thus, reliability as well as a service life of the one-way valve is effectively increased.

Abstract: A hydraulic lash compensation device for an engine includes a plunger assembly slidingly received within a body bore to define a high pressure chamber. The plunger assembly includes a lower pressure chamber, an upper plunger element, and a lower plunger element. A mechanical lift loss feature includes a generally annular lift stop member retained to the upper plunger element by an adjustment member that extends through the lift stop member and is adjustably received in upper plunger element. The lift stop member is biased away from upper plunger element by a spring. When the upper plunger element is received into the body, the upper plunger element is offset a predetermined distance from the lower plunger element by virtue of the lift stop member's engagement with the lower plunger element. The offset is adjustable based on the position of the lift stop member relative to the upper plunger element.

Abstract: The finger follower has an inner and outer body and a torsional lost motion spring positioned at its lash adjuster end of the outer body. The torsional lost motion spring has two helical parts each with a short leg that abuts the outer body and a long leg that contacts the inner body. The torsional spring is located above the pivot point of the finger follower so as to provide a low mass moment of inertia and to reduce the weight over the valve stem end of the follower.

Abstract: A lost motion spring is disposed to contact at one end an oscillating member interposed between a cam and a valve for synchronizing the oscillating of the valve with the rotation of the cam. The lost motion spring impels the oscillating member toward the cam. A spring support shaft is provided for supporting a second portion of the lost motion spring. A spring position adjustment mechanism is provided for adjusting the mounting position of the lost motion spring relative to the spring support shaft.

Abstract: A tappet apparatus cooperates with a valve and a cam. The apparatus includes a case to reciprocate motion of the cam; and a locking unit in the ease, movable between an activated position at which the valve reciprocates motion of the case, and a deactivated position at which the valve is stationary regardless of the motion of the case. The locking unit may include first and second passages in the case; a pin, movable between a first and a second position within the first passage; and a column in the second passage. The pin may be situated in the column when the pin is in the second position. The activated position may be defined by the pin being in the first position, and the deactivated position may be defined by the pin being in the second position.

Abstract: In a Type 2 engine, a valve deactivation hydraulic lash adjuster (DHLA) in accordance with the invention replaces a conventional hydraulic lash adjuster in the train of a gas-exchange valve in a compression-ignited engine. In a Type 3 engine, a similar DHLA is disposed within an articulated rocker arm which is made selectively competent (valve activating) or incompetent (valve deactivating) thereby. A solenoid valve within the assembly diverts hydraulic fluid between support and non-support of a piston slidably disposed in a housing and terminating in a ball head. The valve is force-balanced. The preferred hydraulic fluid is diesel fuel, allowing for smaller diameter passages and cleaner operation than in prior art systems, eliminating the need for an accumulator chamber and accumulator piston as in the prior art. An alternate version of a type 3 engine having a DHLA, in accordance with the invention, is also shown.

Abstract: An internal combustion engine having a cylinder block defining a plurality of cylinders at least half of which are selectively deactivatable by a plurality of switching hydraulic lifters. A source of pressurized oil is provided. Additionally, at least one solenoid-actuated hydraulic control valve operates to selectively communicate pressurized oil from the source of pressurized oil to actuate the plurality of switching hydraulic lifters thereby deactivating the selectively deactivatable cylinders. The number of the solenoid-actuated hydraulic control valves is fewer than the number of selectively deactivatable cylinders.

Abstract: A tappet clearance automatic adjusting device comprising an adjusting unit for advancing/retracting an adjust screw from the forward end of a rocker arm and adjusting the projection amount, a torque detecting section for detecting the torque by rotating the adjust screw, and a control mechanism section for controlling the adjusting unit based on a torque value measured at the torque detecting section. The control mechanism section starts retracting the adjust screw when a valve is opened and continuously measures the torque value obtained when the valve is closed. A position, corresponding to time when variation in the filtering value obtained by smoothing the torque value through moving average is a threshold value or smaller, is detected as a reference point and the adjust screw is retracted from the reference point by a set amount.

Abstract: A tappet assembly includes a first follower engaging a cam lobe profile, and a second follower engaging an engine poppet valve. A latch member is operable to fix the first follower in an extended position, to provide a high lift condition. The first and second followers define first and second stop surfaces, respectively, such that when the latch member is retracted, the lift portion engages the first follower and moves it toward the poppet valve until the stop surfaces engage, and thereafter, further downward movement of the first follower moves the second follower to provide a low lift. One benefit of this feature is to prevent accumulation of unburned fuel in a port fuel injection type of gasoline engine.

Abstract: A variable displacement internal combustion engine having a cylinder block and a cylinder head attached thereto. The variable displacement internal combustion engine includes at least one switching hydraulic lash adjuster. A lash adjuster oil feed passage is at least partially defined by one of the cylinder block and the cylinder head. The lash adjuster oil feed passage is operable to communicate pressurized oil to the at least one switching hydraulic lash adjuster. A distributed accumulator is disposed within the lash adjuster oil feed passage and operates to attenuate oil pressure spikes within the lash adjuster oil feed passage.

Abstract: The invention relates to an axial fixation (17) of a spring support part (9) of a switchable tappet (1) for direct transmission of a cam stroke to a tappet push-rod (7) of a valve drive of an internal combustion engine. The tappet (1) has an inner part (3), which receives the force of a spring means (13), in that the spring support part (9) used as a support (12) for the spring means (13) is fixed axially to the inner part (3) in a direction of force of the spring means (13), such that the spring support part (9) and the inner part (3) face each other in a region of the axial fixation (17) and form a common channel (18) by means of formed parts (20, 23) aligned with each other, in which a retaining ring (19) is arranged for positive-fit connection of the spring support part (9) to the inner part (3).

Abstract: The invention proposes a push-rod valve train having an adjustable valve tappet (1). This has an outer part (2a, 2b), an inner part (8) and a lost-motion spring (10), which forces the inner part (8) towards a relative position, at least one retainer ring (23), which is fixed in an annular groove (21) of the outer part (2a, 2b) and which interacts with a stop face (22) of the inner part (8), being provided for fixing the relative position, said retainer ring having lugs (28) extending radially inwards and separated by a fitting gap (27). In this the free movement of the valve push rod (15) relative to the lugs (28) is assured by the provision of a torsional locking means (30a, 30b), which serves to fix the radial position of the fitting gap (27) inside the annular groove (21).

Abstract: The invention proposes a switching element (1) for a valve train of an internal combustion engine, particularly for valve deactivation, with a simple-to-implement measure for adjusting the coupling lash of its coupling means (8) in a receptacle (6) using two retaining rings (19, 20), one of which is stocked in a variety of thicknesses.

Abstract: A hydraulic lash adjuster includes a cylindrical body having a central cylindrical bore. A hollow plunger is reciprocable in the bore and includes a reservoir chamber therein. The plunger has a close clearance with the bore. A high pressure chamber is defined by the plunger and a closed end of the bore. An orificed wall of the plunger separates the reservoir chamber from the high pressure chamber. A check valve is disposed in the orifice for allowing one-way flow of oil from the reservoir chamber to the high pressure chamber. A plunger spring disposed in the high pressure chamber urges the plunger away from the closed end of the bore. A seat is disposed at an end of the plunger distal from the high pressure chamber. The plunger includes a circumferential groove proximate the seat for holding oil to maintain an oil seal in the clearance to limit leakage of air through the clearance.

Abstract: A switchable valve drive element of an internal combustion engine can be actuated hydraulically. A valve tappet which can be displaced axially in a bore of the machine housing by the cam of a camshaft. A switching duct adjoins the valve tappet and is filled with a hydraulic oil. A connection on the valve drive element between the switching duct and a space with a lower pressure level compared to the pressure in the switching duct. The connection can be produced between the switching duct and the space with a lower pressure level by means of the valve tappet. The space may be inside the tappet.

Abstract: A hydraulic reverse spring valve clearance compensation element (RSHVA) for a valve train of an internal combustion engine comprising: a housing (2), which has a blind bore (3), in which a piston (4) is guided with a tight, sealing clearance; the piston (4) comprises a lower piston part (4a) with a lower piston head (5), which together with the blind bore (3) defines a high-pressure chamber (7), whilst a low-pressure chamber (8) is situated above the lower piston head (5); the pressure chambers (7, 8) being connected by a central axial bore (10) in the lower piston head (5), which is controlled by a control valve (11) arranged on the underside (23) of the lower piston head (5); the control valve (11) comprises a control valve ball (19), upon which a control valve spring (20) acts in the opening direction and the lift of which is limited by a lift-limiting stop (24) of a valve ball cap (21), whereby an RSHVA, the idle lift of which is as independent as possible of the viscosity and hence of the temperature

Abstract: A rail used as a torsional stop for the valve train of an internal combustion engine is disclosed. The rail includes spaces (10) which are arranged in a row spaced apart at a distance from one another within the rail (8) and accommodate inserted valve lifters provided as roller tappets (9). Two parallel torsional stop areas (15) are configured on the outer surface of each roller tappet (9) in the form of planar flattened zones in order to secure the roller tappet (9) against rotation about the central longitudinal axis thereof. The torsional stop areas (15) rest against guide areas of the rail (8), which are located inside the associated accommodating space (10).

Abstract: A switchable support element (1) comprising a housing (2) in whose bore (4) an axially displaceable pressure piston (7) extends, said support element (1) comprising at least one coupling element (8) for an optional coupling of the pressure piston (7) in its axially extended position relative to the housing (2), said pressure piston (7) being biased in an outward direction from the housing (2) by at least one lost motion spring (9).

Abstract: An improved hydraulic lash adjuster including a cup-shaped adjuster body, and a plunger assembly disposed within the adjuster body. The plunger assembly includes a stepped axial bore extending from a body inner end to a central oil passage opening onto a hemispherical pivot head. A check valve cartridge sub-assembly is disposed against the step, defining a low-pressure oil chamber in the axial bore. A lash adjustment spring is disposed against the cartridge sub-assembly in a high-pressure chamber formed between the sub-assembly and the adjuster body. The cartridge sub-assembly may be used in other hydraulic lash adjusters such as are incorporated in hydraulic valve lifters.

Abstract: A valve timing mechanism of an internal combustion engine of a motor vehicle, having a camshaft having at least one cam (18), via which a switchable valve timing mechanism element (1) can be loaded with a cam stroke (s), in which locking means (12) are arranged on the valve timing mechanism element (1), which locking means (12) have a locking play (16) which is active in the direction of a valve stroke, in which the cam (18) has a base circle region (?) and a ramp region (19) with an opening ramp (?) which adjoins the base circle region (?), and in which at least one ramp section (21) is formed on the opening ramp (?) in order to compensate for the locking play (16).

Abstract: A deactivating hydraulic valve mechanism includes a hydraulic element assembly disposed within cup within a pin housing slidably disposed within a bore in a body. A transverse bore in the pin housing contains selectively-retractable locking pins that engage a locking feature in the body to selectively lock together the body and the pin housing. A lost motion spring is disposed in a vented annular chamber between the body and the pin housing. An oil passage from an engine gallery to the hydraulic element assembly includes an axial component formed in the cup and bypasses the lost motion chamber. A ring holds the lifter assembly together and also sets mechanical lash. The ring may combine a standard-thickness ring and a shim selected to provided a predetermined amount of mechanical lash in the assembled mechanism to ensure facile engagement and disengagement of the locking pins in the body.

Abstract: A deactivation valve lifter includes a lifter body. The lifter body has a first end configured for engaging a cam of an engine and at least one annular pin chamber. A pin housing includes a pin housing bottom. The pin housing bottom defines at least one pin stop aperture and a radially directed pin bore. A deactivation pin assembly is disposed within the pin bore and includes pin members. The pin housing is concentrically disposed within the lifter body. A portion of each pin member may be disposed within the annular pin chamber to thereby selectively couple and decouple the lifter body to the pin housing. A drain aperture defined by the pin housing bottom extends from the pin bore to an outside surface of the pin housing. A stop pin is disposed in the at least one pin stop aperture for limiting the inward motion of the pin members.