Abstract: A valve actuation device for actuating a first and second gas exchange valve of an internal combustion engine. A tilting lever is pivotable between a first starting position and a first actuation position and a valve bridge is movable between a second starting position and a second actuation position. A coupling device is switchable between a locking state, in which the valve bridge is movable out of the second starting position into the second actuation position via the coupling device by the tilting lever, and an unlocking state, in which, despite a movement of the tilting lever out of the first starting position into the first actuation position, there is no movement of the valve bridge out of the second starting position into the second actuation position. The coupling device is held on the tilting lever such that the coupling device is pivotable with the tilting lever.

Abstract: A compression-release engine brake system operating an exhaust valve of an engine during a compression-release engine braking operation. The compression-release brake system comprises an exhaust rocker arm and a brake reset device disposed in a reset bore formed in the exhaust rocker arm. The brake reset device comprises a reset check valve, a slider-piston slidably disposed in the reset bore and an external slider bias spring biasing the piston foot away from the brake reset device. The external slider bias spring is disposed outside the reset bore and around the piston-slider. The brake reset device permits pressurized hydraulic fluid to flow from a supply conduit to a reset conduit to supply a brake actuation piston when the reset check valve is open. The actuation piston extends and engages the exhaust valve toward the end of a compression stroke of the internal combustion engine, and the brake reset device resets.

Abstract: A valvetrain assembly comprises a valve bridge, a capsule, a first rocker arm, and a second rocker arm. The valve bridge comprises an upper surface comprising a central pressure point and an offset pressure point and a lower surface comprising a lower pivot point, a first valve interface, and a second valve interface. The capsule can be connected to the lower pivot point, the capsule configured to provide to the pair of engine valves one or both of a lash adjusting function and a deactivating mode. The first rocker arm is configured to actuate against the central pressure point to transfer a first valve lift mode to the valve bridge. The second rocker arm is configured to actuate against the offset pressure point to transfer a second valve lift mode to the valve bridge.

Abstract: A summation rocker system is disclosed for acting on the end of a stem of a poppet valve (16) in dependence upon the combined lifts of a first and a second cam profile defined by different cam lobes (14, 22) of a concentric camshaft (46). The system comprises a first rocker (12) mounted on a pivot shaft (18) and having a first follower (44) to contact the first cam profile and an end acting on the valve (16) to displace the valve (16) by an amount dependent upon the lift of the first cam profile, a rocker shaft (24) to be fixedly mounted on the engine, and a second rocker (20) pivotable about the rocker shaft (24), the second rocker (20) having a second follower (48) to contact the second cam profile and acting to displace the pivot shaft (18) of the first rocker (12) in dependence of the lift of second cam profile.

Abstract: A valve bridge system comprises a valve bridge configured to extend between at least two engine valves of an internal combustion engine. In one embodiment, a valve bridge guide is operatively connected to the valve bridge and configured to extend between at least two valve springs respectively corresponding to the at least two engine valves, the valve bridge guide defining a surface conforming to a valve spring of the at least two valve springs. In another embodiment, the valve bridge guide may comprise at least a first member maintained in a first fixed position relative to and at a predetermined distance from the valve bridge. In both embodiments, the valve bridge guide is configured to avoid contact with the valve bridge in a controlled state, but to permit contact with valve bridge to resist uncontrolled movement of the valve bridge.

Abstract: A cylinder head assembly is for an internal combustion engine. The cylinder head assembly includes a cylinder head and first and second valves coupled to the cylinder head. The first and second valves are associated with a combustion chamber partially defined by the cylinder head. The cylinder head assembly also includes a fixed member coupled to the cylinder head and a valve bridge engageable with the first and second valves. The valve bridge is axially moveable along an axis relative to the fixed member to move the first and second valves together between an open position and a closed position. The cylinder head assembly further includes an anti-rotation feature between the valve bridge and the fixed member. The anti-rotation feature restricts rotational movement of the valve bridge about the axis.

Abstract: In a tappet with a built-in lash adjuster, hydraulic oil is prevented from leaking from a low pressure chamber during a long-period stop. A tappet (10) includes a hydraulic lash adjuster (11) which supports a lower end portion of a push rod (96) and a tappet case (12) to which the lash adjuster (11) is internally fitted and which is reciprocally displaced in a vertical direction according to a rotating cam (85). An inner peripheral surface of the tappet case (12) is provided with an air-vent passage (34) through which air existing between the tappet case (12) and the lash adjuster (11) can be discharged upward when the lash adjuster (11) is being assembled.

Abstract: A transmission element in the form of a rocker arm (1) or swinging arm for a reciprocating piston internal combustion engine is provided that can be actuated on one side by a cam of a camshaft and on the other side is in active connection with at least one gas exchange valve directly or via an intermediate arrangement of a valve bridge. The transmission element has a hydraulic valve lash compensation element, also called “HVA”, and the hydraulic valve lash compensation element is arranged at a force transmission end of and attached to the transmission element.

Abstract: A valve train for a reciprocating piston internal combustion engine with a transmission element in the form of a rocker arm (1) or pivot arm that can be actuated, on one hand, at least indirectly by a cam of a camshaft and is in active connection, on the other hand, through an intermediate connection of a valve bridge (4), with gas-exchange valves (7, 8). The valve bridge (4) has hydraulic valve lash compensation elements (“HVAs”) allocated to each gas-exchange valve (7, 8).

Abstract: A valve actuation system is disclosed for an engine. The system may have at least one gas exchange valve, a rocker shaft, a camshaft, a rocker arm connected to the rocker shaft and operatively engaged with the camshaft, a valve bridge engaged with the at least one gas exchanger valve, a lash adjuster disposed in the valve bridge, and a button configured to slide on the valve bridge. The system may further include a pin fluidly connecting the rocker arm to the button and having an elongated cylindrical shaft with a first open end inside the rocker arm and a second end inside the button. The pin may also have a head connected to and a reservoir formed in the elongated cylindrical shaft. The pin may further have passages extending from the bore of the rocker arm to the reservoir, and s passage extending from the reservoir through the head.

Abstract: A variable valve lift apparatus may include a rocker arm coupled with a rocker arm shaft, a valve bridge disposed to be pressed by one end portion of the rocker arm, the valve bridge including a piston insertion hole and at least one pin insertion hole connecting to the piston insertion hole, a valve disposed to be pressed by the valve bridge, and a variable lift unit disposed in the valve bridge and variably controlling an amount that the rocker arm presses the valve bridge. The variable lift unit includes a variable piston of which the lower portion is inserted into the piston insertion hole, and a check pin disposed in the pin insertion hole to be selectively inserted into the pin groove formed on a side surface of the variable piston according to the hydraulic pressure supplied to the piston oil passage formed in the variable piston.

Abstract: A piston engine, having at least one cylinder that includes at least a first and a second discharge valve and a double overhead camshaft for controlling the first and a second discharge valves. The double overhead camshaft includes both an inner shaft, which has at least one first cam for controlling the first discharge valve, and an outer shaft that is coaxial to the first inner shaft and has at least one second cam for controlling the second discharge valve. The inner shaft and the outer shaft are rotationally adjustable relative to one another changing the discharge time frame of the discharge valves.

Abstract: The disclosed structure achieves a desired balance between higher-rigidity and weight saving in a connection-type rocker arm which integrally rocks a plural of arm portions. The rocker arm has a plurality of arm portions integrally formed on a swinging base end side of the rocker arm which are forked and extend towards a swinging end of the rocker arm, a connecting portion which integrally connects each swinging end of the arm portions, and a concave thinning portion which overlaps a swinging trajectory of the connecting portion, when viewed in the axis direction of the pivot shaft of the rocker arm.

Abstract: A mechanically controllable valve drive includes a gas exchange valve on which a transmission arrangement acts via a working contour. The transmission arrangement comprises a first wheel element comprising a toothing which is connected to a camshaft, and a second wheel element comprising a toothing which acts on the gas exchange valve. The transmission arrangement is mounted to move in a cylinder head via a bearing, and is operatively connected to the camshaft and to a valve stroke adjusting device comprising an adjusting shaft. The first and second wheel elements are each mounted to rotate on the adjusting shaft and to be in a geared connection with each another via their respective toothing so that a rotation of the adjusting shaft effects a phase shift between the first and second wheel elements and so that a rotary fixing generates an oscillating movement of the first and second wheel elements.

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 coupler plate for a multi-valve system of an internal combustion engine. The coupler plate includes an elongated planar body and through holes on opposite ends. The through holes may be either closed or open ended, and of sufficient size to insert valve stems of valves for an internal combustion engine valve system.

Abstract: A rocker arm may include a first arm defining a first longitudinal bore and a second arm defining a second longitudinal bore. The rocker arm may house a locking assembly including a first lock pin located within the first longitudinal bore, an actuation pin extending through a radial passage in the rocker arm and engaged with the first lock pin, and a first biasing member engaged with the first lock pin and urging the first lock pin toward the actuation pin and biasing the actuation pin radially inward. An actuation assembly may be engaged with the actuation pin and linearly displaceable between first and second actuation positions. The first and second arms may be rotatable relative to one another when the actuation member is in the first actuation position and may be fixed for rotation with one another when the actuation member is in the second actuation position.

Abstract: A rocker arm may include a first arm defining a first longitudinal bore and a second arm defining a second longitudinal bore. The rocker arm may house a locking assembly including a first actuation pin extending through a first radial passage in the rocker arm, a second actuation pin extending through a second radial passage in the rocker arm, and a first lock pin located in the first longitudinal bore between the first and second actuation pins. An actuation assembly may be engaged with the first and second actuation pins and may be linearly displaceable between first and second actuation positions. The first and second arms may be rotatable relative to one another when the actuation assembly is in the first actuation position and may be fixed for rotation with one another when the actuation assembly is in the second actuation position.

Abstract: A valve opening arrangement includes a first contact surface on a first member, and a second contact surface on a second member discrete from the first member. A first and a second opening are provided, and a first and a second valve movable to open and close the first and second opening, respectively, are provided. A yoke is arranged to move the first valve and not the second valve when contacted by the first contact surface and is arranged to move the first valve and the second valve when contacted by the second contact surface.

Abstract: In a gas exchange valve actuating device for transmitting a drive movement to at least one gas exchange valve of an internal combustion engine which includes a braking unit having at least one actuator, the gas exchange valve actuating device is provided with a locking unit for locking the actuator counter to an opposing force when the actuator has reached a specific position.

Abstract: The present invention provides a variable valve lift including a housing, a plurality of swing arms that are rotatably arranged at the housing, and a plurality of latching mechanisms for selectively latching the plurality of swing arms.

Abstract: In a V-type engine, intake and exhaust rocker arms in each bank are arranged in a substantially inverted-V-shape in a plan view, so that side end portions of corresponding intake and exhaust push rods are positioned adjacent to each other. Slipper portions of first and second intake cam followers have end portions at one end along the axial direction of a camshaft protrude respectively in opposite directions to each other so that they face each other across an intake cam therebetween. Slipper portions of first and second exhaust cam followers have end portions at one end along the axial direction of the camshaft protrude respectively in opposite directions to each other so that they face each other across an exhaust cam therebetween. This reduces the distance between the push rods in each bank to provide a compact valve-operating device.

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: A valve opening arrangement includes a first contact surface on a first member, and a second contact surface on a second member discrete from the first member. A first and a second opening are provided, and a first and a second valve movable to open and close the first and second opening, respectively, are provided. A yoke is arranged to move the first valve and not the second valve when contacted by the first contact surface and is arranged to move the first valve and the second valve when contacted by the second contact surface.

Abstract: An engine that includes two intake and two exhaust valves for each cylinder is equipped for single valve constant lift engine braking. The exhaust valves may be actuated in a conventional manner via a rotating cam and a rocker arm coupled to a bridge that spans between the pair of exhaust valves. Engine braking is accomplished by actuating a brake actuator to hold one of the exhaust valves partially open, while the other of the two exhaust valves is allowed to close. Seating velocity of the non-braking valve is limited by including a second actuator button, namely a valve seating actuator, on the rocker arm that engages the valve bridge above the non-braking valve as it moves toward its closed position when the brake actuator is actuated.

Abstract: A device for retaining a valve bridge is disclosed. The valve bridge is engaged with a plurality of valves. The device has a first base member. The first base member is configured to engage at least one of the plurality of valves. The device also has a first latching member. The first latching member extends from the first base member. The first latching member is configured to engage and retain the valve bridge in engagement with the plurality of valves.

Abstract: A rocker assembly for a valve train having a first valve, a second valve, and a pushrod is provided. The rocker assembly includes a rocker having a first arm in contact with the first valve, a second arm in contact with the second valve, and a third arm in contact with the pushrod, the first arm having a bore formed therethrough. An adjustable swivel foot includes a first portion having threads and a second portion, the adjustable swivel foot coupled to the first arm such that the first portion extends through the bore of the first arm and the second portion is engageable with the first valve, and a threaded member is included that is engaged with the threads of the first portion of the adjustable swivel foot, the threaded member operable to position the second portion relative to the rocker.

Abstract: An internal combustion engine having a plurality of intake and/or exhaust valves associated with each cylinder includes a valvetrain having a fulcrum with a plurality of pivot ball sockets each associated with a rocker arm and pivot ball disposed between the fulcrum and the rocker arm with the fulcrum extending through apertures of the rocker arms and having a plurality of slots, each slot having generally parallel opposing lateral surfaces for receiving and guiding both sides of an associated rocker arm so the rocker arm pivots about the pivot ball in a plane of the rocker arm. The fulcrum can accommodate at least two rocker arms that may operate in non-parallel planes relative to one another and can include bearing and locating surfaces integrally formed to finish dimensions to eliminate machining.

Abstract: Otto cycle internal combustion engine, comprising a cylinder block including at least one cylinder having a longitudinal axis, a piston movable within said cylinder and having a recess open on a head surface of the piston, a head fastened to said cylinder block and having a surface facing the cylinder, three intake valves and two exhaust valves movable along respective rectilinear directions, a combustion chamber delimited at one side by a portion of the surface of the head facing the cylinder and, at the other side, by the surface of said recess of the piston. The directions of motion of the valves are parallel to each other, the surface of the head facing the cylinder is planar and orthogonal to the directions of motion of the valves and the combustion chamber is obtained exclusively in the piston.

Abstract: An engine that includes two intake and two exhaust valves for each cylinder is equipped for single valve constant lift engine braking. The exhaust valves may be actuated in a conventional manner via a rotating cam and a rocker arm coupled to a bridge that spans between the pair of exhaust valves. Engine braking is accomplished by actuating a brake actuator to hold one of the exhaust valves partially open, while the other of the two exhaust valves is allowed to close. Seating velocity of the non-braking valve is limited by including a second actuator button, namely a valve seating actuator, on the rocker arm that engages the valve bridge above the non-braking valve as it moves toward its closed position when the brake actuator is actuated.

Abstract: A valve operating system for an engine that includes a piston that reciprocates along a piston axis. The valve operating system includes a valve member that is movable along a valve axis between a first position and a second position and a crankshaft that is rotatable about a crank axis. A cam member includes a substantially non-planar non-cylindrical surface and a cam profile superimposed thereon. A drive linkage interconnects the cam member and the crankshaft such that the cam member rotates in response to rotation of the crankshaft. A rocker arm is engaged with the valve member and the cam profile to move the valve member in response to rotation of the cam member.

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 multiple valves operated by a common lifter and pushrod that engages a follower having multiple independent lash adjusters coupled to associated rocker arms. The lifter contacts the common camshaft lobe and a corresponding pushrod that engages a reciprocating bucket follower with a compliant coupling to corresponding rocker arms.

Abstract: A variable valve device for an internal combustion engine comprises a first switching oil passage which is formed along an axial direction in one of a rocker shafts, the first rocker arm being switched to the first mode by applying oil pressure to a first rocker arm through the first switching oil passage, and a second switching oil passage which is formed along an axial direction in the other rocker shaft, a second rocker arm being switched to the first mode by applying oil pressure to the second rocker arm through the second switching oil passage. The first switching oil passage and the second switching oil passage are formed in a ladder shape in which the first switching oil passage and the second switching oil passage communicate via a plurality of relay oil passages.

Abstract: An exhaust gas recirculation (EGR) system for use in a four-stroke, internal combustion, compression-ignition engine having at least one engine cylinder, at east one combustion chamber, at least one intake valve and a crankshaft. The EGR system includes at least one exhaust gas intake valve that is opened during at least a portion of an engine intake stroke when the exhaust gas pressure is greater than the pressure of gas in the combustion chamber, thus allowing exhaust gas to flow into the combustion chamber to establish internal EGR. A cam-operated intake rocker arm assembly has the form of both a first class lever and a second class lever. The first class lever directly communicates motion of the intake rocker arm assembly to open the intake valve, and the second class lever communicates motion of the intake rocker arm assembly through a hydraulic transfer assembly to open the exhaust gas intake valve.

Abstract: In a valve drive for a piston internal combustion engine with a first rocker lever which is in operative contact with at least a first cylinder valve, wherein a cam structure including a first cam and at least one additional cam is in active contact with a second rocker lever, which can be placed in force transmission contact with the first rocker lever by an actuator element for transferring the pivot motion generated by the first and second cams selectively from the second rocker lever to the first rocker lever and at a rate depending on an idling angle determined by the actuator element.

Abstract: A first camshaft (24) operates the exhaust valves (18) and a first intake valve (12) for each cylinder (8), and a second camshaft (38) operates the second intake valve per cylinder (14), the second camshaft further having a phase adjuster (62) for adjusting the timing of the second camshaft (38) relative to the first camshaft (24). Both the exhaust valves and the first intake valve are actuated by rocker arms (30), (36), for providing a short and light-weight first intake valve rocker (36) having a high maximum operational speed capability and low friction. The first camshaft (24) is located above the rockers, the cam followers are located generally in the middle of the rockers (30), (36), and the rocker mounts (33), (35) are located on the inboard ends of the rockers, providing rockers that have both light-weight and a small pivot angle for providing low valve stem to rocker friction.

Abstract: A valve operating mechanism is described for an internal combustion engine in which at least one valve (14) of an engine cylinder is operated by two cams (10,12). The cams (10,12) have respective cam followers (38,36) which are resiliently biased to remain in contact with the cams (10,12) at all times and which act on the valve (14) by way of a summation linkage (20,24) in such a manner that the displacement of the valve (14) at any instant is determined by a combination of the displacements of the two cam followers (38,36). In the invention, movement of each of the two cam followers (38,36) is transmitted to the summation linkage (20,24) by way of a respective one of two pushrods (28,30).

Abstract: Mechanical controls for continuously varying the length of the stroke of the valves in an internal-combustion engine and for maintaining the valves constantly closed while the engine is in operation while simultaneously varying how long the valve or valves remain open, whereby the valves are actuated by rocker levers that are in turn actuated by an angled lever, whereby the positions of the levers are varied in order to vary the length and duration of the stroke. The valves are actuated at low engine speeds by assigning a specific narrow angle of rotation to each abbreviated stroke to be established. FIG. 1 illustrates valve stroke controls with an angled lever (2) actuated by a cam (17) mounted on a lateral roller (3). In the event of a misalignment, a planetary gear comes into play, wherein a roller (9), mounted on the rocker lever (8) that actuates the valve (1) acts a sun wheel, the angled lever (2) acts as a planet wheel, and a setting lever (5) acts as a planet bearing.

Abstract: Disclosed is a rocker arm shaft for an automobile engine, which is effectively capable of offsetting the length change of the rocker arm shaft, which caused by heat. According to an embodiment of the present invention, a rocker arm shaft can be divided into at least two shafts. An elastic member, such as a coil spring, is positioned between the shafts. When the length change of the shafts is changed by heat, the elastic member offsets the changed length of the shafts. The rocker arm shaft is divided into a hollow first shaft and a hollow second shaft. A one end of the second shaft of the rocker arm shaft forms a receiving groove for inserting the elastic member. With this structure, the rocker arm shaft for an automobile engine does not bend nor get twisted by offsetting the changed length of the shafts by means of the elastic member.

Abstract: A roller rocker mounting mechanism for an internal combustion engine valve actuating mechanism includes a first rocker stand having a first locating boss and a second rocker stand having a second locating boss. An indexing link has a first portion separably attachable to the first locating boss and a second portion separably attachable to the second locating boss to connect the first rocker stand and the second rocker stand in a manner that prevents rotation of either rocker stand when the rocker stands are attached to the cylinder head.

Abstract: A rocker arm 1 includes an arm body 4 prepared from a single plate material by means of a press work. The arm body 4 includes a pair of parallel side walls 5 and a connecting wall 6 bridging between the opposite side walls 5 and also having a pivot support hole 7 defined at a location generally intermediate of the length of the arm body 4. A roller support pin for rotatably supporting a roller 10 for driving engagement with a cam is mounted on one ends 1a of the opposite side walls 5, while the opposite end 1b of the connecting wall 6 defines an overlapped structure 13 formed by bending an end overlap piece 12, extending integrally from a side edge of the connecting wall 6, backwardly to overlap the connecting wall 6. This overlapped structure 13 in turn defines an adjustment element 16 having a mounting hole 15 defined therein for adjustably receiving a valve driving member 14. The rocker arm 1 may be designed to be an end pivot type, in which case the adjustment element 16 is provided with a pivot member.

Abstract: A variable valve mechanism has a switching mechanism for transmitting cam displacement to a first rocker arm from a second rocker arm. A camshaft is disposed obliquely above a rocker shaft. A first abutting portion and a second abutting portion are disposed in a dead space between an upper side of the rocker shaft and a side of the camshaft. The first abutting portion rotationally displaces in a rotational direction of rocker arms together with the first rocker arm. The second abutting portion rotationally displaces together with the second locker arm. The second abutting portion abuts on the first abutting portion from a rotating direction of rocker arms. In the switching mechanism thus configured, displacement of the second rocker arm is transmitted to the first rocker arm with reduced stress burden.

Abstract: Mechanical controls for continuously varying the length of the stroke of the valves in an internal-combustion engine and for maintaining the valves constantly closed while the engine is in operation while simultaneously varying how long the valve or valves remain open, whereby the valves are actuated by rocker levers that are in turn actuated by an angled lever, whereby the positions of the levers are varied in order to vary the length and duration of the stroke. The valves are actuated at low engine speeds by assigning a specific narrow angle of rotation to each abbreviated stroke to be established. FIG. 1 illustrates valve stroke controls with an angled lever (2) actuated by a cam (17) mounted on a lateral roller (3). In the event of a misalignment, a planetary gear comes into play, wherein a roller (9), mounted on the rocker lever (8) that actuates the valve (1) acts a sun wheel, the angled lever (2) acts as a planet wheel, and a setting lever (5) acts as a planet bearing.

Abstract: A valve train is disclosed for an internal combustion engine having a block, a camshaft in the block, and at least two push rods actuated by the camshaft. The valve train comprises first and second rockers, and three valves. The first rocker is actuated by one of the push rods, and the second rocker is actuated by another of the push rods. A first valve is associated with a cylinder of the engine and actuated by the first rocker. A second valve is associated with the cylinder and actuated by the first rocker, and a third valve is associated with the cylinder and actuated by the second rocker.

Abstract: To provide an internal combustion engine that can generate a strong swirl by increasing the amount of intake air for generating the swirl in a simple structure. In the internal combustion engine provided with a cylinder head formed with an air intake port having first and second ports, when a second intake valve for opening and closing the second port is brought into a halted state by a valve halting mechanism, a swirl is generated by intake air flowing through the first port in a combustion chamber.

Abstract: In an OHV engine in which a pair of cylinder blocks is connected to the crankcase and power from a cam is transmitted to a rocker arm pivotably supported by the cylinder heads via connecting rods, to enable downsizing of the engine while reducing the number of components and the number of assembling steps. A part of the connecting rods out of the respective connecting rods are respectively stored in a rod storage chamber provided in both cylinder heads, both cylinder blocks and a crankcase between the cylinder axes of the adjacent cylinder bores in the respective cylinder blocks. The remaining connecting rod disposed outwardly of the cylinder axes of the outermost cylinder bores laid along the axis of the crankshaft is stored in part in a pipe member disposed at the position away from the outer walls of the cylinder blocks.

Abstract: There is provided a valve actuation linkage mechanism for use in an internal combustion engine that reduces friction wear on the valve assembly during engine operation and can be pre-assembled to reduce manufacturing time and costs. The valve actuation linkage mechanism comprises a rocker arm having a pivot rod cup, a pivot rod, a valve bridge having a pivot rod chamber, and a pivot rod retainer. The pivot rod comprises a pivot rod head, a pivot rod neck, a pivot rod body, and a pivot rod bottom. The valve bridge comprises a middle valve bridge section having the pivot rod chamber and a pair of pivot rod retainer securing bore, a bottom valve bridge section, and a lubricant dimple in the pivot rod chamber. The pivot rod retainer is comprised of a pivot rod orifice having pivot rod prongs and at least one securing orifice.

Abstract: The thickness in the width direction of a pair of side wall sections 4 is made as uniform as possible. In use, a load is applied to the pivot 3 from the side of the first and second connecting sections 5, 6 which connect the pair of side wall sections 4. A crimped section 13a is formed on the outer periphery at the opposite end surfaces of the pivot 3b, on the half on the side of the connecting sections 5, 6. Therefore, the outer peripheral surface of the opposite ends of the pivot 3b comes into contact with the inner peripheral surface of the through hole 11 on the load support side. Consequently, the load is sufficiently supported by the contact surface, and even after being used for a long time of period, lost motion is prevented from occurring on the support section at the opposite ends of the pivot 3 with respect to the pair of side wall section 4.

Abstract: In an arm type valve gear in which a lash adjuster is mounted between an arm pivoted by the rotation of a cam and a valve stem, it is aimed to reduce the axial length of the lash adjuster and to suppress wear at the contact portion with the valve stem. An engaging hole is formed in an arm pivoted by the rotation of a cam at a position corresponding to the top end face of a valve stem. A lash adjuster received in the engaging hole includes a nut member, an adjuster screw in threaded engagement with the nut member, an elastic body biasing the adjuster screw toward the valve stem, and a ball joint to reduce the axial length of the lash adjuster. Further, by bringing the bottom end face of the ball joint into surface contact with the top end face of the valve stem, wear at the contact portion is suppressed.