Abstract: A desmodromic drive (30) for imparting reciprocal translation to a valve (32) has a cam ring (52) that rotates about an axis (42), a follower (50) that reciprocates with axial motion as the ring rotates, an endless cam track (69) on the ring, and rollers (76, 78) on the follower that ride along the cam track as the ring rotates. A follower guide (48) guides the follower for axial. Rollers (60, 62) constrain the follower against rotation on the follower guide.

Abstract: A cam with a bore that has a funnel-shaped core-insertion section. To ensure that the cam will rest more securely against the core and remain more precisely centered, the section (5) comprises at least two mutually aligned conical extents (6 & 7), each expanding outward at a different apical angle.

Abstract: A VVA apparatus includes a driving shaft, a crank cam arranged at an outer periphery of the driving shaft, a VO cam swingably supported by the driving shaft to actuate an engine valve, and a rocker arm having a first arm swingably mounted to an eccentric control cam at a first pivotal point and a second arm rotatably mounted to the crank cam and the VO cam at a second pivotal point and a third pivotal point, respectively, the rocker arm transmitting a driving force of the crank cam to the VO cam. The valve lift produced by the VO cam is varied by changing a rocking fulcrum of the rocker arm through rotation control of the control cam, and the second pivotal point and the third pivotal point are located on the side of the second arm of the rocker arm.

Abstract: A drive train for an overhead valve engine, including a cam gear driven by the crankshaft, the cam gear supported for rotation in the cylinder block externally of the cylinder head and having a cam lobe mounted thereon for actuating a pair of rocker arms mounted for rotation in the cylinder head, which in turn actuates intake and exhaust valves in the cylinder head. A first lubrication passageway is provided in the crankcase of the engine to communicate oil, pumped from the oil sump by a combination oil pump and governor assembly driven from the crankshaft, to the upper crankshaft bearing. A second lubrication passageway is provided in the crankshaft and communicates oil from the upper crankshaft bearing to the coupling between the crankshaft and the connecting rod.

Abstract: An assembly to secure an engine camshaft is provided that includes: a cylinder head provided with a plurality of concave parts into which the camshafts are placed, the concave parts allowing for rotation of the camshafts; and a full cam carrier mounted to the cylinder head over the camshafts and allowing for the rotation of the camshafts, the full cam carrier including a plurality of ribs corresponding to positions of the concave parts and integrally formed to the full cam carrier at predetermined intervals.

Abstract: A variable camshaft assembly has a first cams 18a, 18b that can be moved relative to a second cam 16. The assembly comprising a tube 14 fast in rotation with the first cam 18 and rotatably supporting the second cam 16 and a drive shaft 12 disposed within the tube 14 and coupled for rotation with the second cam 16 by means of a connecting pin 20 that passes with clearance through a hole 24 in the tube 14. The connecting pin is a hollow pin 20 that is a sliding fit in the second cam 16 and that is expanded in situ to form an interference with the drive shaft 12.

Abstract: A sliding member (12) is disclosed that has superior slidability and durability at a low cost. A top sliding surface (12a) of the sliding member (12) is formed by a nitriding process that creates a compound layer (14) and a diffusion layer (15) on a base metal (16) of the sliding member (12). The buff polishing process is thinly performed on an outermost layer portion (14a) of the compound layer (14), such that a portion of the compound layer (14b and/or 14c) remains.

Abstract: An improved compact engine construction that facilitates positioning in close quarters while still affording ease of assembly and servicing. This is accomplished by mounting the camshafts at different heights and by providing a two-piece spark plug tube in the cylinder head that facilitates removal in sections rather than all at once.

Abstract: A camshaft used in an internal combustion engine which has reduced weight and added wear resistance at a lobe of the camshaft. The camshaft is provided to add increased wear resistance and reduced weight to the internal combustion engine for increased efficiency of the internal combustion engine. The camshaft includes wear resistant material at the surface of the lobe of the camshaft. The wear resistant material is distributed on the outer surface of the lobe and incorporated into the base material.

Abstract: An internal combustion engine includes a cam which actuates a valve by torque of a camshaft and is movable in the radial direction of the camshaft and includes a lift portion which moves forward and backward in the direction of the valve, a support mechanism which rotates the cam with the camshaft, and a device which engages the cam with the camshaft and releases the cam from the camshaft in accordance with engine operating conditions.

Abstract: A drive for pump-nozzle injection elements and injection pumps of an internal combustion engine. The drive includes a crankshaft, a camshaft for actuating the injection elements, and form-locking traction member for drivingly connecting the crankshaft to the to the camshaft so that torque angles change in a synchronous manner. The camshaft has cams which are optimized in each case for an injection process with respect to stroke velocity and thus feed rate of fuel. The cams are configured so that the torque angle or a range of torque angles (&agr;VHmax) before TDC of the cams at which the cams produce a maximum fuel feed rate deviates by an angle &agr;a from an optimum angle before TDC (K). An amount by which the angle deviates from the optimum angle in a direction toward TDC is no more than an angular error (&agr;F) resulting from an increase in length of the traction means during operation.

Abstract: A variable valve mechanism includes an elongate input shaft having a central axis. An input cam lobe is disposed on the input shaft and is eccentric relative to the central axis. A guide member is pivotally mounted on the input shaft. A frame is disposed in engagement with the input cam lobe, and is pivotally and slidably coupled to the guide member. A link has a first end pivotally coupled to the frame. An output cam is pivotally mounted on the input shaft. The output cam is pivotally coupled to a second end of the link arm. The output cam is configured for oscillating engagement of a roller of a roller finger follower.

Abstract: An automatic decompression device for an internal combustion engine includes a camshaft rotatable about an axis of rotation and having an end face, and a lever coupled to the end face and movable between a first position, wherein the lever is engageable with a valve actuating device to actuate a valve during rotation of the camshaft, and a second position, wherein the lever does not substantially move the valve actuating device. The lever is preferably pivotally coupled to the end face to pivot about a pivot axis that is substantially perpendicular to the axis of rotation of the camshaft. Further preferably, the automatic decompression device further includes a spring between the end face and the lever to bias the lever toward the first position. In a highly preferred embodiment, the end face of the camshaft includes a slot and the lever is at least partially retained within the slot.

Abstract: The valve drive mechanism is particularly suitable for internal combustion engines of motor vehicles. The mechanism has at least one driven cam element and a valve control member which is moved (translationally or rotationally) by the cam element. The cam element is rotatingly mounted in a flexible surround element which is connected to the valve control member in a plane orthogonal to the axis of rotation of the cam element. The surround element can be reversably extended, such as elastically extended, to enable a variation in the resulting valve lift.

Abstract: A camshaft used in an internal combustion engine which has reduced weight and added wear resistance at a lobe of the camshaft. The camshaft is provided to add increased wear resistance and reduced weight to the internal combustion engine for increased efficiency of the internal combustion engine. The camshaft includes wear resistant material at the surface of the lobe of the camshaft. The wear resistant material is distributed on the outer surface of the lobe and incorporated into the base material.

Abstract: A valve lift mechanism, in particular for internal combustion engines of motor vehicles, has a driven cam element, a valve control member which can be driven (translational movement or pivot rotation) by the cam element, and a flexible enveloping element, wherein the cam element is rotationally mounted The enveloping element is movably connected to the valve control member in the plane perpendicular to the axis of rotation of the cam element.

Abstract: A multi-cylinder internal combustion engine with at least one cylinder row is equipped with a cylinder head housing containing intake and exhaust valves that feed combustion air to the cylinders and release combustion exhaust gases through an exhaust system via control devices in dependence of the position of the crankshaft. Devices for generating differing exhaust valve lift progressions of at least two cylinders arranged in one cylinder row are incorporated to reduce overlapping opening phases of these exhaust valves. The intake valve and the exhaust valve of one of the two cylinders are themselves in an overlapping opening phase. Thereby, a uniform filling rate of the cylinders with new gas is achieved, particularly on a V-8 engine with a 90°-bent crankshaft.

Abstract: A variable valve mechanism includes an elongate input shaft having a central axis. An opening cam lobe and a closing cam lobe are disposed upon the input shaft. The opening cam lobe and the closing cam lobe have a predetermined angular relation relative to each other and relative to the central axis. A rocker assembly has a first end and a second end. The rocker assembly carries a roller that engages the opening cam lobe. A first split frame member assembly is pivotally mounted upon the input shaft. The first split frame member assembly is pivotally coupled at a first end thereof to the rocker assembly. The first split frame member assembly is configured for being pivotally coupled at a second end thereof to a control shaft. A first split output cam is pivotally mounted upon the input shaft, and a link pivotally couples the first split output cam to the second end of the rocker assembly.

Abstract: A variable valve actuating mechanism includes a rocker having a central rocker axis that is substantially parallel with and spaced apart from a central axis of a rotary input shaft. A frame member has a first end configured for being pivotally mounted upon the input shaft and a second end pivotally carrying the rocker. A connecting rod has a first end configured for engaging an eccentric of the rotary input shaft and a second end pivotally attached to the rocker. The connecting rod transfers rotation of the input shaft to oscillation of the rocker relative to the rocker central axis. An output cam is configured for being pivotally mounted upon the input shaft. An output cam gear is affixed to the output cam. A crank gear is affixed to the rocker and engages the output cam gear.

Abstract: A ring gear variable valve train device is provided for installation on an internal combustion engine having a rotary input crankshaft provided with a cylindrical eccentric journal having a center offset from the rotational axis of the shaft. A connecting rod disposed on the journal is reciprocated by rotary motion of the input shaft. A frame disposed on the input shaft may be controllably varied to vary the lift and timing of the valve. A rocker arm pivotably disposed on the frame is attached to the connecting rod to oscillate a ring gear portion of the rocker arm in response to rotary motion of the input shaft, which ring gear drives a planetary-geared output cam to actuate an engine intake valve to open and close. The teeth of the ring gear and the planetary gear are axially tapered, and a coil spring disposed on the output shaft is operative axially to displace the planetary gear axially of the ring gear to eliminate gear lash therebetween.

Abstract: In a combination of the shim 5 and cam 1 for use in a reciprocating mechanism portion, the shim 5 is made of a material having a hardness higher than that of the sliding surface of the cam 1 and the sliding surface of the shim 5 is finished to within a range of the surface roughness of Rz0.07-0.2 &mgr;m in 10-point mean surface roughness and further the sliding surface of the cam 1 is provided with open pores 1b. In the above combination, the generated torque and the wear of sliding portion are minimized by selecting a shim member whose surface roughness is difficult to deteriorate due to plastic deformation by a injection pump contact with a mating member and corrosion by various impurities mixed in lubricant and the like, and providing the surface of a cam member with an oil film holding function so as to maintain fluid lubrication of the sliding surface.

Abstract: A valve actuating mechanism is disclosed which comprises a valve (12), a camshaft having a cam (22) of fixed profile associated with the valve (12), a valve lifting rocking cam (24) pivotable about a fixed axis and having a contoured surface that acts to open and close the valve (12) as the rocking cam (24) pivots about said fixed axis, and a cam following rocker (26) comprising a cam follower (46) in contact with the fixed profile cam (22) on the camshaft and coupled to the rocking cam (24) in order to cause the rocking cam (24) to pivot about the fixed pivot axis with rotation of the camshaft. The rocker (26) is pivotable about a second axis that is movable relative to the fixed pivot axis of the rocking cam (24) in such a manner as to allow the valve lift, phase and duration of the valve event to be varied in dependence upon the position of the pivot axis of the rocker (26).

Abstract: In a direct injection engine which comprises an injector (22) for directly injecting fuel into a combustion chamber (15) and a lean NOx catalyst (36), an ECU (50) changes the air-fuel ratio from that higher than the stoichiometric air-fuel ratio to that substantially equal to or lower than the stoichiometric air-fuel ratio. When the air-fuel ratio has changed from a air-fuel ratio higher than the stoichiometric air-fuel ratio to an air-fuel ratio substantially equal to or lower than the stoichiometric air-fuel ratio, the ECU controls to divisionally execute fuel injection from the injector (22) in at least two injections, i.e., leading injection that starts within the intake stroke period and trailing injection that starts within the compression stroke period.

Abstract: The present invention is directed to a modular camshaft assembly having an elongated shaft, at least one cam lobe assembly, at least one spacer assembly, and a cam adapter assembly. Each cam lobe assembly is selectively secured to the elongated shaft. Each spacer assembly is secured to the elongated shaft, wherein the spacer assembly is selectively positioned adjacent the cam lobe assembly. The cam adapter assembly is secured to the elongated shaft and adapted to connect the modular camshaft assembly to a drive assembly.

Abstract: A variable valve timing and lift structure for a four-cycle internal combustion engine wherein a high speed and low speed cam are associated with the camshaft, each for operating the same valve. The high speed cam is supported for movement relative to the camshaft and this movement includes relative rotation. A coupling device selectively couples the second cam for rotation with the camshaft so as to operate the valve during at least a portion of its opening and closing movement when so coupled. When the second cam is not so coupled, the first cam controls the entire motion of the valve. The first and second cams are related so that at least one of these cams can operate two adjacent valves for the same cylinder, thus simplifying the overall construction.

Abstract: An electromagnetic driving device of engine valve for internal combustion engine comprising an electromagnetic deriving mechanism includes a first and second electromagnets positioned opposite each other, an armature disposed in a gap formed between the electromagnets for moving therebetween, a follower having a first and second followers that are positioned opposite each other is for moving in relation to the armature, a valve associated with the armature for closing and opening an intake or exhaust passage, a first and second cams having gradually varied their profile are pivoted for contacting respective the first and second followers, a spring is disposed between the follower and the cams for urge the first and second cams toward the first and second followers, respectively.

Abstract: This invention describes an engine valve control responsive to electrical signals from a controller to open and close a valve. Power to move the valve comes from a camshaft. A disabler spring is compressed by a cam lobe and held compressed by its solenoid while the valve is held from opening by its solenoid. When the valve solenoid releases the valve, a half oscillation between the disabler spring and valve spring opens the valve and the valve solenoid than holds it open. The disabler solenoid then releases the disabler spring. When the valve solenoid releases its spring, a half oscillation of the two springs closes the valve with a soft landing. The valve operation is very fast, independent of engine speed, and can be controlled over 630 crankshaft degrees. The camshaft may run at crankshaft speed with valve disablement during compression and expansion strokes for 4 stroke operation. 2 stroke operation may be used for compressor and air motor operation as a pneumatic hybrid engine.

Abstract: A hollow cam shaft is composed of a hollow shaft having an inner hollow portion and an end piece which is pressure-welded to at least one end of the hollow shaft. The end piece comprises an end member which is pressure-welded to the one end of the hollow shaft and an enclosure member extending from the end member in an axial direction thereof so as to be inserted into the inner hollow portion of the hollow shaft at a time of pressure welding to define an enclosure space in the inner hollow portion of the hollow shaft. The enclosure member comprises a sealing portion having an outer shape substantially the same as an inner shape of the hollow shaft and a connection portion connecting an end surface of the end member of the end piece and the sealing portion so as to define said enclosure space between the enclosure member and the hollow shaft into which a burr generated at the pressure welding time is enclosed.

Abstract: A method of manufacturing a camshaft comprises the first step of casting a blank defining a central shaft, concentric journal bearings and eccentric cam lobes, the cam nose region between the journal bearing at the driven end of the camshaft and the adjacent cam lobe being cast in the same non-circular shape as the cam lobe but with smaller dimensions. The cam nose and the cam surface of the first cam lobe are then ground. Preferably, the cam lobe surface and the cam nose are ground at the same time as one another by means of a shaped grinding wheel having a cylindrical portion for grinding the cam surface and a narrower contoured portion of larger diameter at one end for grinding the cam nose.

Abstract: In a valve mechanism of an internal combustion engine having a cylinder with a pair of air-intake valves, the number of operation modes of the air-intake valves in accordance with engine operation region is increased to improve combustion nature in a combustion chamber and engine output and to miniaturize the valve mechanism. The valve mechanism comprises first and second drive rocker arms operatively connected with the respective air-intake valves, first, second and third free rocker arms coming into contact with first, second and third operation cams having profiles for making the air-intake valve perform opening-closing motion.

Abstract: An overhead cam engine with a drive train including a crankshaft, connecting rod, and piston assembly for reciprocating the piston within the cylinder bore of a cylinder block. A cam ring rotates on the same axis as that along which the piston reciprocates, and has lobes on its upper surface for periodically actuating a pair of rocker arms which open and close intake and exhaust valves located within the cylinder head. The cam ring is driven at half speed by the crankshaft through a gear train arrangement including a timing shaft disposed on an axis parallel to the piston axis with gears at both ends for connecting the crankshaft with the cam ring.

Abstract: A cam shaft bearing insert is provided for use in a cam shaft support bearing for operably supporting a cam shaft in an internal combustion engine. The engine includes a cylinder head with bearing support towers that operably support journals on the cam shaft at multiple aligned bearing locations. Each bearing support tower has an oil port for passing oil to the associated journal. The bearing insert further has a thin-walled cylindrical sleeve formed from thin flat stock into a cylindrical tubular shape that is adapted to fit into one of the bearing support structures and form a bearing surface suitable for supporting the cam shaft. The sleeve has an outer surface with an outwardly deformed area configured to non-rotatably engage the one bearing support structure and has an aperture therein so that, when the aperture is aligned with the oil port of the one bearing support structure, oil can pass from the oil port to the associated bearing location.

Abstract: An internal combustion engine includes a housing with a plurality of bearing supports. Each bearing support has a substantially circular interior bearing surface. A segmented camshaft assembly includes at least two camshafts axially adjacent to each other to define at least one adjacent pair of camshafts. Each camshaft is rotatably carried by the housing and includes a plurality of cam lobes. The camshaft assembly also includes at least one connector assembly, with each connector assembly connecting an adjacent pair of camshafts together. Each connector assembly has an exterior bearing surface disposed within and rotatably carried by a corresponding interior bearing surface in the housing.

Abstract: An improved and simplified outboard motor construction wherein the cooling and exhaust systems for the engine are formed with a minimum number of components and sealing joints and incorporating a non-metallic cam shaft for reduced cost and weight without sacrifice of durability. The exhaust system includes an elongated expansion chamber formed in the drive shaft housing. In addition, the drive shaft housing has a cylindrical section that is journaled within a swivel bracket for its steering movement. The volume between the external portion of the drive shaft housing and the internal portion of the swivel bracket forms a second expansion chamber that is employed for the low speed above the water exhaust gas discharge. The flow of cooling the water to and from the engine is controlled so that the exhaust gas interchange area between the power head and the drive shaft housing will be well cooled, as will the oil reservoir for the engine and the oil returned to it.

Abstract: A multi-valve internal combustion engine having a plurality of valves having skewed axes that are operated by cam lobes of a single cam shaft. The cam shaft operates the valves through rocker arms each of which are pivoted independently about axes that are skewed relative to the cam shaft axis so as to minimize bending stresses on the valve during its actuation. This also avoids scuffing between the rocker and the valve stem. At the same time, good contact is maintained between the cam lobe and the follower surface by machining the cam lobe so that it will have a slight concavity at least in its tip portion so as to ensure constant line contact with the follower.

Abstract: A low friction cam shaft for actuating at least one valve of an internal combustion engine includes a shaft member extending longitudinally, at least one cam secured to the shaft member, the cam being made of a plurality of density metal materials and having an outer surface impregnated with a solid film lubricant that has an affinity for oil and promotes rapid formation of a stable oil film to reduce friction therebetween.