Abstract: A castellation device comprises a shaft surrounded by three castellation members. A first castellation member is rotatably mounted on the shaft and comprises a first end and a second end opposite to the first end. A second castellation member is slidably mounted along the shaft adjacent the first end of the first castellation member. A third castellation member is mounted to the shaft adjacent the second end of the first castellation member. A bias spring is disposed between the second castellation member and the third castellation member and is configured to bias the second castellation member away from the third castellation member. Optionally, an annular shroud can enclose the three castellation members. The first castellation member is rotatable relative to the second and third castellation members between a first position and a second position.

Abstract: In variable displacement engines, a portion of the intake valves have deactivatable valve lifters. When the engine conditions are such that some of the cylinders are to be deactivated, the intake and/or exhaust valve lifters in those cylinders are deactivated. Operation of the mechanism inside the lifter that is actuated to deactivate the valves can be harmed when particles in the engine oil get inside. To prevent small particles entering the valve lifter, a small filter is provided just upstream of the orifice into which oil enters the valve lifter. In other embodiments, a wire mesh formed into a coil is inserted into the recess. In some applications, a cage with snap-fitting connectors is installed over the filter to keep the wire mesh in place and properly coiled. The cage also fits into the recess. Such filter may also be applied to a hydraulic lash adjuster feature in a lifter.

Abstract: A variable valve mechanism includes an input arm that axially supports a roller pressed by a cam, via a roller pin, an output arm that drives a valve when swinging, a switch device that switches the variable valve mechanism between a coupled state where the both arms are coupled and an uncoupled state where the arms are uncoupled from each other, and a lost motion spring that biases the roller against the cam when in the uncoupled state. The lost motion spring includes an extended portion extending in an inter-arm clearance between the input arm and the output arm. An end of the roller pin projects from the input arm into the inter-arm clearance by such a length that the end is accommodated in the inter-arm clearance and that allows a spring retaining portion to be formed in the end. The spring retaining portion is formed in the end.

Abstract: A columnar-type hydraulic tappet, provided with a housing, a plunger moving axially with respect to the housing being mounted in an inner cavity of the housing, a high pressure cavity used for a hydraulic medium extending between a lower end surface of the plunger and a lower side of the housing, a first ring groove being arranged below a head portion of the plunger, a second ring groove being arranged at a central portion of the plunger, a plunger central wall being between the first ring groove and the second ring groove, the second ring groove being a concave wide ring groove, wherein at least one plunger oil inlet hole being arranged on the plunger concave wide ring groove or the plunger central wall, a bottom portion edge of the plunger oil inlet hole containing flanging facing towards an inner cavity of the plunger.

Abstract: A retention plate for a hydraulic lash adjuster of a valve train is provided. The retention plate includes a first surface. The retention plate includes a second surface mutually opposite the first surface. The second surface is adapted to contact with a cylinder head of an engine. The retention plate also includes a coupling mechanism defined on the retention plate. The coupling mechanism is adapted to couple the retention plate to the cylinder head. The coupling mechanism includes a through hole adapted to receive a mechanical fastener therethrough. The retention plate further includes a restriction mechanism defined on the retention plate. The restriction mechanism is adapted to restrict a movement of the hydraulic lash adjuster beyond the first surface towards the cylinder head. The restriction mechanism includes an aperture having an aperture size smaller than an outer diameter of the hydraulic lash adjuster.

Abstract: A novel latch seat for a switching rocker arm assembly used in variable valve actuation (VVA) systems for internal combustion engines. The seat is formed interactively in the assembled switching rocker arm using a novel fixture and press. The press interactively creates a curved dimple of the correct curvature, position and depth while measuring several lash dimensions. Since the latch seat is formed on the assembled rocker arm assembly, the latch seat depth is designed to account for the inaccuracies in the rocker arm assembly parts which create lash. Therefore all of the parts may be made with less precision since the latch seat is sized to compensate for the inaccuracies of all of the parts. The rocker arm assembly parts now may be manufactured to less stringent standards, but result in a rocker arm assembly with same accuracy of rocker arm assemblies manufactured to previous standards.

Abstract: A columnar hydraulic tappet comprises a housing, in which a plunger is correspondingly mounted. A high-pressure chamber extends between a lower end surface of the plunger and a lower side of the housing. An outer ring groove is disposed on the outer diameter of the housing, an inner ring groove is disposed in the radial inner side of the housing, and housing oil feed holes are disposed between the inner ring groove and the outer ring groove. The lower end inside the housing is provided with a grinding wheel groove, an upper end wall of the inner ring groove of the housing is a first internal cylindrical wall, and a housing inner-wall between the lower end of the inner ring groove of the housing and the grinding wheel groove is a second internal cylindrical wall.

Abstract: A hydraulic lash adjuster having a reduced number of elements, yet capable of suppressing air from infusing into a high-pressure chamber. A plunger is fitted in a body. A reservoir is formed in the plunger. The plunger's head portion is formed with a communication hole for communicating its interior with its exterior. A high-pressure chamber is disposed and between the plunger and the body. An oil supply hole is formed in the peripheral wall of the plunger. A return spring is provided between the body and the plunger. A valve mechanism is provided at the plunger's bottom. Provided on the inner periphery of the plunger is an inclined area, subjected to impingement of oil jet ji and serving as an impingement area, such that the impingement area is inclined to fall in the direction of the ejected oil as the area nears the plunger's head portion.

Abstract: The mechanical lash adjuster is arranged between a cam and one end of the stem of a valve urged by a valve spring. The lash adjuster comprises an unrotatable housing having a thread, a plunger subjected to the force of the cam and formed with a thread in engagement with the thread of the housing, and a plunger spring urging the plunger against the action of the valve spring. The lead and flank angles of the engaging threads are set such that the engagement threads can slidably rotate under a given shaft load applied to the plunger unless the frictional torque TB, generated by the friction between the slidable frictional surface F2 of the plunger and a shaft load transmission member to act on the plunger, exceeds the thrust torque TF imparted by the shaft load to the plunger.

Abstract: A lash adjustment device is for a valve train in a marine engine. The lash adjustment device comprises an external hollow body and a ball shaft that is telescopically movable in the hollow body. The ball shaft has a through-bore for receiving oil and having an annular lower end surface and an upper end surface. Oil flow into the hollow body pushes on the lower end surface and forces the ball shaft to telescope outwardly with respect to the hollow body. An absence of oil flow in the hollow body allows the ball shaft to telescope inwardly with respect to the hollow body until the annular lower end surface engages with an internal stop surface formed in the hollow body.

Abstract: A lash adjuster includes a body, a plunger inserted, into the body and having a bottom wall formed with a valve hole and a peripheral wall standing from the bottom wall and having an oil passage hole, the plunger defining a high-pressure chamber between the bottom wall and the body, a partitioning member inserted into the plunger and having an oil passage end located above the oil passage hole, the partitioning member defining an oil passage between itself and the plunger peripheral wall, the partitioning member having a low-pressure chamber reserving a hydraulic fluid flowing through the oil passage hole, the oil passage and the oil passage end, the low-pressure chamber causing the reserved hydraulic fluid to flow through the valve hole into the high-pressure chamber, and a spacer interposed between the plunger peripheral wall and the partitioning member so that the partitioning member is held in the plunger.

Abstract: The present invention provides a variable valve mechanism of an internal combustion engine, which includes a main arm having at a rear end thereof a supported portion that is continuously supported swingably by a support member without floating upward, a sub arm which has a tip end to which a roller contacting a cam is rotatably attached, in which a center of the roller is located rearward of the pressing portion and forward of a swing center of the supported portion, which has a rear end that is swingably supported with respect to the main arm by a support pin, and in which a center of the support pin is located rearward of the center of the roller and forward of the swing center of the supported portion, and a switch pin that is inserted in a central portion of the roller.

Abstract: A valve drive of an internal combustion engine, having a finger lever which acts at one end on a gas exchange valve and which is seated at the other end on a head of a housing of a support element, which housing runs in an axially movable manner in a reception bore of a cylinder head, the finger lever is acted on by a cam from the base circle from which there projects in a fixed manner an additional cam piece for generating an additional lift of the gas exchange valve, a bore extends from a bottom of the housing in the direction of the head, in the lower portion of which bore there runs a pressure piston which is axially movable relative to the housing and via the lower face of which the support element is mounted on a base of the reception bore of the cylinder head, a high-pressure chamber for hydraulic medium is formed between an upper face of the pressure piston and a ring part situated above said upper face and which is fixed with respect to the housing, and to generate the additional lift, the high-press

Abstract: A retention device to secure a finger follower and lash adjuster of a valve actuating mechanism together includes a ring member disposed in a groove of a movable piston of the lash adjuster. The retention device also includes a plurality of connecting members formed from the finger follower and extending axially below the ring member and about a portion of the lash adjuster to engage the ring member in all operating positions of the valve actuating mechanism as a result of the pivoting motion of the finger follower.

Abstract: A device for varying the relative angle position of a camshaft with respect to a crankshaft of an internal combustion engine. A circlip fixes the valve housing in a positively locking manner. The circlip has at least one radially extending circumferential portion which is designed to engage into an annular groove arranged in the camshaft or in the rotor in the axial end region of said camshaft or rotor, wherein the circlip has at least one axially extending retaining portion, wherein the control piston has, in one of the face regions thereof, an annular groove which is designed for the engagement of the at least one axially extending retaining portion, and wherein the valve housing has, in one of its face regions, at least one hook-shaped portion for engaging behind at least one radially extending circumferential portion of the circlip.

Abstract: A valve actuation mechanism for an internal combustion engine includes rockers moved by a camshaft, each rocker being adapted to exert a valve opening force on at least a portion of a valve actuation mechanism of each cylinder belonging to a housing of the engine, via an engine brake activation piston, housed in a bore of the rocker, and movable with respect to the rocker under action of a fluid pressure raise in a chamber fluidly linked to the bore, from a first position, in which an engine brake function is deactivated, to a second position, in which a roller of the rocker reads at least one engine brake bump of a cam of the camshaft so as to perform the engine brake function. Each rocker includes a discharge valve movable in translation with respect to the rocker, adapted to reduce fluid pressure in the chamber.

Abstract: An apparatus for actuating at least one outlet valve of a valve-controlled internal combustion engine for motor vehicles, includes an actuating element which is driven by a camshaft. A first piston/cylinder unit, preferably a hydraulically loaded piston/cylinder unit, is provided between a cam of the camshaft and at least one outlet valve. The piston/cylinder unit allows at least one outlet valve to be held in a non-closed intermediate position during an engine braking mode with exhaust-gas backpressure. A second piston/cylinder unit is provided which is configured as a valve-play compensation element, preferably as a hydraulic valve-play compensation element (HVC). At least one valve train-side device is provided between the cam and the at least one outlet valve, which valve train-side device exerts a force which is directed counter to the adjusting action of the HVC but is lower than the latter.

Abstract: A valve lash adjustment system for setting a valve to a rocker arm clearance for a valve train associated with a particular combustion cylinder for an engine is disclosed. The valve lash adjustment system includes a frame assembly including an engine head attachment portion and an instrument attachment portion. The engine head attachment portion of the valve lash adjustment system is removably attachable to the engine and the instrument attachment portion is selectively positionable relative to the engine head attachment portion. The valve lash adjustment system also includes an instrument assembly including at least one position sensor and at least one display unit. The valve lash adjustment system further includes a gap setting gauge assembly having a clip member.

Abstract: A cylinder head assembly includes a first member coupled to an engine block and a second member coupled to the first member. The first member defines a first port in communication with a first cylinder and a second port in communication with a second cylinder. The second member defines a longitudinally extending portion located on a first lateral half of the first member. A first control passage and a second control passage are defined between the first member and the longitudinally extending portion of the second member. The second member defines a wall separating the first and second control passages from one another.

Abstract: An engine valve system comprises two cams (10,12) mounted coaxially, a summation rocker (14) coupled to followers (16,18) of both cams and movable in proportion to the instantaneous sum of the lifts of the respective cams, and a valve actuating rocker (20) pivotably coupled to the summation rocker (14) and operative to open an engine valve (22) in dependence upon the movement of the summation rocker (14). In the invention, the actuating rocker (20) rests on a hydraulic lash adjuster (24). A control spring (136) is provided to urge the summation rocker (14) in a direction to compress the hydraulic lash adjuster (24). A stop (138) associated with the control spring (136) limits the movement of the summation rocker (14) towards the lash adjuster (24) so as to set the clearance in the valve system when the valve (22) is closed and the cam followers (16,18) are on the base circles of the two cams (10,12).

Abstract: A rocker arm assembly may include a body, a cam follower and a lash adjustment member. The body may define a pivot region and a valve engagement region. The cam follower may be coupled to the body. The lash adjustment member may be coupled to the cam follower and may include a locking portion and an adjustment arm extending radially outward from the cam follower.

Abstract: The present invention provides a rocker arm with a lash adjuster which includes a rocker arm body portion including a circular fitting hole, a large-diameter hole, and a step portion at a boundary between the fitting hole and the large-diameter hole; a lash adjuster having a snap ring groove formed on an outer circumferential surface of the lash adjuster, and a snap ring fitted to the snap ring groove, wherein the lash adjuster is inserted in the fitting hole, the snap ring increases in diameter, hooks on the step portion, and prevents the lash adjuster from slipping off; and a diameter-reducing member that is assembled in the rocker arm body portion and that reduces the diameter of the snap ring by operation of the diameter-reducing member from an outside of the rocker arm body portion until the snap ring is not engaged with the step portion.

Abstract: A valve actuation mechanism for an internal combustion engine includes rockers moved by a camshaft, each rocker being adapted to exert a valve opening force on at least a portion of a valve opening actuator of each cylinder, via an activation piston, housed in a bore of the rocker and movable with respect to the rocker under action of a fluid pressure raise in a chamber fluidly connected to the bore, from a first position to a second position with respect to the rocker, in which a cam follower of the rocker is adapted to read at least one auxiliary valve lift sector of a cam of the camshaft so as to perform an engine operating function. Each rocker includes a check valve adapted to control the fluid pressure raise in the chamber.

Abstract: A hydraulic lash adjuster includes a body defining an axial bore and having an open end and a closed end. A hollow piston is telescopically received within the axial bore and defines a fluid reservoir. The hollow piston has a first end disposed within the axial bore and a second end extending outwardly beyond the open end of the body. A high pressure volume is defined by the axial bore and the first end of the hollow piston. The hydraulic lash adjuster also includes a valve mechanism positioned through an opening of the hollow piston and including a valve member having an open position defining a fluid path from the fluid reservoir to the high pressure volume. The valve member also has a closed position in which the fluid reservoir is fluidly blocked from the high pressure volume at the opening. The hollow piston includes a band of radial recirculation openings defining recirculation paths from the high pressure volume to the fluid reservoir along an exterior of the hollow piston.

Abstract: An assembly for a valve drive of an internal combustion engine, which has a hydraulic support element and a cam follower connected by way of a clamp. The follower rests on one end via a cap on a spherical head of a pressure piston of the support element. The piston extends in a bore of a housing of the support element. The clamp flanks the cap with holding strips along the sides. The inner sides run in a guide zone on the outer shell of the piston. The housing has an opening for hydraulic fluid that can be conducted between the housing and the piston through at least one passage in the piston to a storage chamber. The guide zone on the piston is also designed as an anti-rotation mechanism therefore. The piston is installed in a defined manner and is torsionally oriented in relation to the cam follower.

Abstract: A variable valve lift apparatus includes a cam, a swing arm of which one end thereof a valve is connected to and the swing arm contacting the cam, a support portion selectively supporting the other end of the swing arm, a hydraulic lash adjuster of which an oil supply hole and an oil exhaust hole thereto, and selectively supporting the swing arm according to oil supplying thereto or oil exhausting therefrom, a check valve selectively opening the oil exhaust hole and a control portion controlling the check valve for the check valve to selectively open the oil exhaust hole.

Abstract: A valve operating mechanism includes a pin housing housed in a lash adjuster and a lash adjustment chamber. A sync pin is slidably received within the housing between an activating position and a deactivating position. A ball valve assembly is provided within the housing for communication with the chamber, and is moveable between an open position and a closed position. The valve operating mechanism is operable in an active mode and a deactive mode. In the active mode, the sync pin is in the activating position, a valve is in an active state and the valve operating mechanism is configured to adjust valve lash. In the deactive mode, the sync pin is in the deactivating position and the valve is in a deactive state. The valve operating mechanism is configured to generate valve lash to allow the operating mechanism to move between the active mode and the deactive mode.

Abstract: A switching rocker arm assembly can include an outer arm, an inner arm and a latch assembly. The outer arm can have one or more high lift lobe contacting surfaces, where each of the high lift lobe contacting surfaces has an uppermost point that defines an outer arm tangent plane. The inner arm can be pivotably secured to the outer arm and have a low lift lobe contacting surface. The low lift lobe contacting surface can have an uppermost point that defines an inner arm tangent plane that is parallel to the outer arm tangent plane. The inner arm tangent plane can be spaced from the outer arm tangent plane by a minimum distance. The latch assembly can be movable between a first configuration in which the outer arm rotates with the inner arm, and a second configuration in which the outer arm rotates independently from the inner arm.

Abstract: A valve lash setting method for setting a predetermined lash in a valve assembly for internal combustion engines. The method includes generating a torque curve and using a linear regression calculation to define a zero crossing point from which a predetermined final lash position of an adjusting screw can be set and secured.

Abstract: The invention concerns a roller tappet (1) for a high pressure fuel pump, said roller tappet (1) comprising a housing (2) comprising on a drive side front end (3), a slide-mounted roller (4) serving as a running surface of a cam, said housing (2), as viewed in housing direction, comprising a bridge member (5) arranged below the roller (4), said bridge member (5) comprising on a front end (7) turned towards a driven side front end (6) of the housing (2), a support (8) for a tappet follower member, wherein a shell member (11) like a semi shell or a one-third shell separated out of a rolling bearing ring is seated in a cylindrical cavity (9) of a further drive side front end (10) of the bridge member (5), and the roller (4) extends for sliding displacement directly in said shell member (11).

Abstract: A switching rocker arm having an outer arm having a first end, a second end, a first and second outer side arm having slider pads that ride on a second cam is disclosed. The switching rocker arm also has an inner arm disposed between the first and second outer side arms. The inner arm has a first end, a second end and a bearing disposed between the first and second end adapted to ride along a first cam. The inner arm is pivotably secured adjacent its first end to the outer arm adjacent its first end. At least one arm has an over-travel limiter structure limits pivoting motion of the first arm relative to the second arm. The switching rocker arm also exhibits decreased lash as the bearing wears, and increased lash as the latch and slider pads wear.

Abstract: The present invention provides a rocker arm with a lash adjuster which includes a rocker arm body portion including a circular fitting hole, a large-diameter hole, and a step portion at a boundary between the fitting hole and the large-diameter hole; a lash adjuster having a snap ring groove formed on an outer circumferential surface of the lash adjuster, and a snap ring fitted to the snap ring groove, wherein the lash adjuster is inserted in the fitting hole, the snap ring increases in diameter, hooks on the step portion, and prevents the lash adjuster from slipping off; and a diameter-reducing member that is assembled in the rocker arm body portion and that reduces the diameter of the snap ring by operation of the diameter-reducing member from an outside of the rocker arm body portion until the snap ring is not engaged with the step portion.

Abstract: A switchable roller finger follower for a valvetrain of an internal combustion engine. The switchable roller finger follower includes an elongated body, a cam follower, a locking pin assembly, lost motion springs and a shuttle pad assembly moving horizontally. The locking pin assembly includes a locking pin and hydraulic fluid supply channel, selectively locking and unlocking the shuttle pad assembly, allowing either a high lift or low lift profile to achieve contact with pre-determined profiles of a multi-lobe camshaft which, in turn, provides low lift or high lift operation of an associated gas exchange valve.

Abstract: A system and method of actuating one or more engine valves is disclosed. In one embodiment, the system comprises: a valve train element; a rocker arm pivotally mounted on a shaft and adapted to rotate between a first position and a second position, the rocker arm selectively receiving motion from the valve train element; a valve bridge disposed above the one or more engine valves; and a lost motion system disposed in the valve bridge.

Abstract: To achieve further reduction in size and weight of a cylinder head in a four-cycle engine having a connection surface formed on the cylinder head to connect a head cover set so as to follow along a plane that is inclined so as to be spaced further away from a cylinder block toward a first side wall. A camshaft holder is integrally formed on a cylinder head so as to protrude from a connection surface as viewed from an axial direction of a camshaft. An intake port is disposed in the first side wall such that an upstream end thereof is disposed at the same position as part of the bearing portion in a direction along an axis of a cylinder bore. An exhaust valve has a stem end disposed at a position protruding from the connection surface as viewed in a direction along the axial direction of a camshaft.

Abstract: A rocker arm unit which constitutes a valve gear of an internal combustion engine, includes a lash adjuster including a cylindrical body and a plunger formed into a cylindrical shape and accommodated in the body, a rocker arm extending in a direction perpendicular to a vertical direction, and a clip configured to be fixed to an upper end of the body and formed with a retainer having a retaining portion which is configured to be swaged onto an inner circumferential surface of the upper end of the body. The clip has an extension extending integrally from the retainer. The extension has an upper end engaged with the rocker arm to prevent the rocker arm from falling off the lash adjuster. The retaining portion is configured to abut against the stepped portion of the plunger from above to prevent the plunger from coming off upwardly out of the body.

Abstract: A cold-formed flat top plunger blank is provided for use in a hydraulic lash adjuster. An end wall at the first end of the plunger body defines a flat top surface that is cold-formed to final dimensions or net shape. The flat top surface at the first end of the plunger body is configured to engage a flat surface within the mating bore of an engine cylinder head. By configuring the plunger body to have a flat top surface that engages a flat surface disposed within the mating bore of an engine cylinder head, the force applied to the engine block by the lash adjuster is distributed more evenly, minimizing wear. The external flat top plunger is a unitary component cold-formed to near net shape, including cold-forming to final dimensions the flat top surface and a counterbore.

Abstract: A method is disclosed for assembling a valve operating system for opening and closing a poppet valve mounted on an engine cylinder head. The valve operating system comprises a camshaft 18 having two coaxial cams 14 and 16 for operating the valve 12, a summation lever 20 coupled to followers 24,26 of the two cams 14 and 16, a control spring 40 acting on the summation lever 20 to urge one of the cam followers 26 into contact with the associated cam 16, and a valve actuating rocker 30 pivotably connected to the summation lever 20 and acting on the valve 12 to open and close the valve in dependence upon the sum of the instantaneous lifts of the two cams 14 and 16.

Abstract: The present invention provides a valve actuation system comprising a valve train for actuating a valve, the valve train including actuating elements and a valve lash, and a valve lash adjustment system for adjusting the valve lash, wherein the valve train and the valve lash adjustment system do not share any common actuating elements.

Abstract: A variable valve lift apparatus may include a variable valve lift housing, a master piston which is slidably disposed in the variable valve lift housing and contacts a cam, a slave piston which is slidably disposed in the variable valve lift housing, defines an oil chamber with the master piston therebetween, and opens a valve connected to the slave piston according to reciprocative motion of the master piston, and a lift control portion which supplies oil to the oil chamber or exhausts oil in the oil chamber selectively to control a relative distance between the master piston and the slave piston.

Abstract: A finger follower having an inner and outer body and a torsional lost motion spring acting between the bodies is provided. A roller cam follower is connected to the inner body. The inner body is switchable from a fixed state, in which it moves with the outer body to transfer a cam lift to a valve stem, to a released state, in which the inner body can move relative to the outer body so that the cam lift is not transferred to the valve stem. A separate valve pallet that acts on the valve stem is press fit or otherwise rotationally fixed on a pivot pin connecting the inner and outer bodies.

Abstract: A hydraulic lash adjuster capable of retaining a Large amount of hydraulic oil in a reservoir communicated with a high-pressure chamber when the engine is stopped. The hydraulic lash adjuster including: a cylindrical body (24) having an upper open end, a closed bottom, and a second oil supply hole (27a) formed in the sidewall of the cylindrical body; and a plunger having a top end serving as a plunging end, a sidewall, a bottom end, a high pressure chamber (29) at the lower bottom, and a first oil supply hole (24b) formed in the sidewall, the plunger being slidabic on the inner wall of the body. The plunger has a reservoir (28) that communicates with an external oil supply line (32) via the first oil supply hole (24b) and the second oil supply hole (27a).

Abstract: The finger follower employs two independent lost motion arms and a rod which moves longitudinally to lock both arms. The rod is transversely mounted in the follower. In order to avoid premature locking, a clip is employed with tabs that interact with end surfaces of the arms so as to prevent premature movement of the rod from an unlocked position to a locked position.

Abstract: There are provided first and second extending oil passages supplying operational oil to intake-side and exhaust-side lash adjustors, a first connection oil passage interconnecting one end portions of the oil passages, and an oil-pressure control valve selecting a first state in which the first extending oil passage does not connect to a drain oil passage or a second state in which the first extending oil passage connects to the drain oil passage. An orifice is provided in an oil passage which is located on the side of the first connection oil passage relative to a supply portion of the operational oil supplied to the lash adjustor and located on the side of the first connection oil passage relative to another supply portion of the operational oil supplied to the lash adjustor.

Abstract: An internal combustion engine includes a camshaft, a valve, a cam follower and a rocker arm. The cam follower is coupled between the camshaft and the valve. The rocker arm is coupled between the cam follower and the valve. At least one of the cam follower and the rocker arm is configured so as to move through an adjustable distance prior to transmitting motion for moving the valve.

Abstract: A lash adjuster is provided which can be easily assembled and mounted in an arm type valve mounted and in an engine. The valve lifter includes an arm (3) pivotable about a rocker shaft (2), and a lash adjuster (20) mounted in a fitting hole (12) formed in the arm (3) at one end thereof for eliminating a valve clearance. The lash adjuster (20) includes a cylindrical body (21), an adjusting screw (23) held in threaded engagement with an internal thread formed on the inner periphery of the body (21), and a torsion coil spring (31) for applying a rotational moment to the adjusting screw (23) that tends to move the adjusting screw (23) downwardly. With the adjusting screw (23) in threaded engagement with the internal thread (22) of the body (21), the adjusting screw (23) is screwed into the body (21) until the adjusting screw (23) is retracted into the body (21).

Abstract: A rocker arm assembly may include a body, a cam follower and a lash adjustment member. The body may define a pivot region and a valve engagement region. The cam follower may be coupled to the body. The lash adjustment member may be coupled to the cam follower and may include a locking portion and an adjustment arm extending radially outward from the cam follower.

Abstract: The object is to provide a lash adjuster that can be easily and repeatedly mounted on a swing arm type valve gear, having an adjusting screw that can be repeatedly held in a pushed-in state with a general-purpose turning tool such as a wrench. A serrated internal thread 24 is formed on the inner circumferential face of a cylindrical body 21 having closed bottom end, and a serrated external thread 26 formed on the outer circumferential face of an adjusting screw 25 engages with the internal thread 24. A return spring 27 is mounted in the body to bias the adjusting screw 27 in the protruding direction. A friction member 31 is provided between the bottom faces of the adjusting screw 25 and the body 21. A spherical pivot portion 32 is formed on the top of the adjusting screw 25, and an engaging hole 33 is formed in the top end of the pivot portion 32.

Abstract: An end pivot valve train is provided in a cylinder head to open and close a cylinder valve. The end pivot valve train includes a cam follower forcing the cylinder valve, and a cam holder assembled onto an upper portion of the cylinder head and includes a receiving groove to receive the cam follower therein, wherein the cam holder has a protrusion configured and dimensioned to interfere with an upper surface of the cam follower when the cam follower rotates such that a longitudinal edge thereof moves up.

Abstract: A lash adjuster is provided which includes a cylindrical housing having an open top and formed with an internal thread on an inner periphery thereof, a screw rod having an external thread formed on an outer periphery thereof and in threaded engagement with the internal thread, and a spring biasing the screw rod outwardly of the housing. Each of the internal thread and the external thread having a pressure flank configured to receive pressure when a force that tends to push the screw rod into the housing acts on the screw rod, and a clearance flank having a smaller flank angle than the pressure flank. The screw rod has an end protruding from the housing and configured to support an arm of a valve operating mechanism so as to be pivotable about this end. Oil film expelling grooves are formed in the pressure flank of the external thread, using a tap having a thread that extends so as to cross the internal thread.