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 may be formed of an open loop with two ends connected by a holder of said valve actuator, and it is movably connected to the valve control member in the plane perpendicular to the axis of rotation of the cam element.

Abstract: A camshaft rotational detection structure is configured that can improve the precision with which the camshaft rotational angle is detected. The camshaft rotational detection structure detects the rotational angle of a camshaft to which rotation is transmitted from the crankshaft of an engine through a cam sprocket mechanism. The camshaft rotational detection structure is provided with a cam thrust flange, a detection target, and a sensor. The cam thrust flange is provided on the camshaft near the end of the camshaft where the cam sprocket mechanism exists and serves to restrict axial movement of the camshaft. The detection target is provided on the cam thrust flange. The sensor is arranged facing opposite the detection target and is configured to detect the rotational angle of the camshaft.

Abstract: A diesel engine intake cam profile creates two intake valve events separated by a short dwell period each engine cycle. A relatively low valve lift during an engine exhaust event allows a portion of the exhaust gas to flow into an intake manifold and mix with intake air. The intake valve is then nearly closed for a dwell period until a normal intake valve opening occurs, drawing the mixture of air and exhaust gas back into the combustion chamber for compression and burning, upon closure of the intake valves.

Abstract: A barrel engine has an elongated power shaft defining a longitudinal axis. A plurality of cylinders surround the longitudinal axis, with each having a closed end and an open end. An intake system introduces a combustible mixture of air and fuel into each of the cylinders. The power shaft has an intake lobe and an exhaust lobe extending therefrom. The intake system includes an intake valve and an exhaust valve for each of the cylinders. A valve actuation mechanism includes an intake rocker arm with one end in mechanical communication with the intake lobe, the other end in mechanical communication with the intake valve, and a mid-portion that is pivotally supported. The mechanism also includes an exhaust rocker arm with one end in mechanical communication with the exhaust lobe, the other end in mechanical communication with the exhaust valve, and a mid-portion that is pivotally supported.

Abstract: A camshaft has a cylindrical shaft (1) and a hollow, cylindrical cam (2). The hollow, cylindrical cam (2) is pushed onto the cylindrical shaft (1) and securely fixed to the cylindrical shaft (1) in terms of rotation and displacement. The hollow, cylindrical cam (2) is provided with a foot strip (2.2, 2.3) that borders the cylindrical shaft (1) on one side and is welded to the cylindrical shaft (1) along, and through, the foot strip (2.2, 2.3).

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 multicylinder internal combustion engine has a valve chamber containing a valve train for opening and closing intake valves and exhaust valves, and decompression mechanisms. First, second and third cylinders are arranged in a row parallel to an axial direction parallel to the axis of a camshaft. An exhaust cam for opening and closing the exhaust valve, which is opened and closed by the decompression mechanism, for the second cylinder is not coincident with respect to the axial direction with an abutment end of the exhaust valve with which a rocker arm driven by the exhaust cam comes into contact, and is coincident with respect to the axial direction with the decompression mechanism. Thus, a space for placing the decompression mechanism is secured while suppressing increase in the length of the camshaft and in the longitudinal size of the valve chamber. Consequently, the internal combustion engine can be formed in compact construction.

Abstract: A shim attaching and detaching surface has a sectional portion with a smaller diameter than a base circle of a cam surface in a state in which the shim attaching and detaching surface of a cam is located on a tappet roller, and therefore the tappet roller and an arm member can be moved upward. Since an inner side of a top surface of a tappet guide is inclined, if the arm member is tilted along this inclination, one end of the arm member can be raised, and a clearance is formed in a space from a tappet shim. Accordingly, by inserting a slim plate-shaped or rod-shaped jig 128 from the clearance, the tappet shim 37EX can be attached and detached.

Abstract: A valve driving device including a tappet assembly adapted to slide in a tappet guide hole to drive a valve and including a high-speed center tappet and low-speed side tappet; and a high-speed center cam and a low-speed side cam provided corresponding to the center tappet and the side tappet. A depression is formed which is depressed from a base circle to roughly the same profile as a shaft section of the camshaft so that the cam portion over a predetermined angle range where a cam nose section is not formed in the centrally located center cam is smaller than the base circles of the outside located side cams in profile.

Abstract: A variable duration valve timing camshaft is disclosed. The camshaft has a shaft with fixed cam lobes and lobe modifying elements that are adapted to move outwardly as the rate of rotation of the camshaft increases thereby cooperating with the lobes to continuously increase the angular distance at constant radius of each fixed valve lobe's nose. The lobe modifying elements are further adapted to move inwards as the rate of rotation of the camshaft decreases thereby continuously decreasing the angular distance of constant radius of each fixed valve lobe's nose until it equals that of the fixed lobe. The lobe modifying elements are pivotally connected to the camshaft.

Abstract: An improved cam and follower arrangement suitable for actuating, for example, poppet valves of an internal combustion engine and method and apparatus for forming the cam surface. This permits the use of skewed valve axes without using multiple rocker arms for each valve. The shapes are chosen and formed to provide better contact area and permits the cams to be ground with conventional grinding methods and for multi-cylinder engines.

Abstract: A camshaft assembly 16 is disclosed for an engine 10, along with a method of producing the camshaft 16. The camshaft includes a support shaft 22 that carries in the region of one end 26 a camshaft element. The camshaft element may comprise a rotation sensor target member 24 and the support shaft 22 is preferably a tubular shaft. The camshaft element 24 is captured onto the support shaft 22 by deforming a deformation zone 46 at the end of the support shaft 22 into a radially extending rivet head 28.

Abstract: A variable timing duration camshaft has an outer shaft (1) and coaxial inner shaft (2) adapted so that the shafts (1, 2) are relatively slidable but not rotatable about each other. The outer shaft (1) has valve control lobes located on its outer surface and a valve control lobe modifying segments (4) is located on the inner shaft (2) and is slidingly fitted into a mating slot (5) in the outer shaft and in the valve control lobe whereby longitudinal axial movement of the inner shaft (2) relative to the outershaft by a control means (13, 14) causes the modifying segment (4) to move longitudinally and circumferentially relative to the valve control lobes thereby varying the duration.

Abstract: The present invention provides a valve train for an internal combustion engine, capable of preventing the minute slippage between the cam lobe and the roller follower, and thereby reducing the friction loss in the valve train system. At least one of the following measures is applied to the valve train. Measure 1: A cam lobe made of an iron sintered material is used, and the surface roughness Ra of the outer circumferential surface thereof is made to be in a range of 0.4 to 2.2 &mgr;m. Measure 2: The surface roughness Ra of the outer circumferential surface of the roller of the roller follower is made to be in a range of 0.4 to 2.2 &mgr;m.

Abstract: A camshaft rotational detection structure is configured that can improve the precision with which the camshaft rotational angle is detected. The camshaft rotational detection structure detects the rotational angle of a camshaft to which rotation is transmitted from the crankshaft of an engine through a cam sprocket mechanism. The camshaft rotational detection structure is provided with a cam thrust flange, a detection target, and a sensor. The cam thrust flange is provided on the camshaft near the end of the camshaft where the cam sprocket mechanism exists and serves to restrict axial movement of the camshaft. The detection target is provided on the cam thrust flange. The sensor is arranged facing opposite the detection target and is configured to detect the rotational angle of the camshaft.

Abstract: A structure for a camshaft includes a cam angle detecting element arranged to face a cam angle sensor and supported in a cantilever manner by a cam journal on the outer side of the cam journal. An extension journal between the cam journal and the cam angle detecting element is enlarged toward the cam journal such that the external diameter on the side of the cam journal may be larger than the external diameter on the side of the cam angle detecting element.

Abstract: A method for producing an assembled shaft, especially an assembled camshaft, whereby parts, especially cams, are placed on a shaft in predetermined axial and peripheral positions and joined by compression pressure in a friction-tight manner. The cams in the thrust direction have a lubrication groove which surrounds the inner bore thereof and which is essentially wedge-shaped with a linear or curved slope, running in the direction of the wall of the bore. When the cam is slid on the shaft into the predetermined axial position, a lubricant is introduced into the groove. This lubricant is pulled continuously groove into the inner bore of the cam during the push-on process to significantly reduce friction between the inner bore and the shaft.

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: The invention provides a control method of intending to improve a heat efficiency by an Atkinson cycle, improve a charging efficiency, improve an efficiency of a supercharger and increase a freedom of cam design. In particular, the invention relates to a control method of opening and closing a valve in an internal combustion engine with supercharger. An effective compression ratio is decreased by temporarily re-opening an exhaust valve in a compression stroke first stage, whereby a heat efficiency is improved without excessively increasing a cylinder internal pressure. Preferably, an exhaust valve re-opening time is set such that the effective compression ratio/expansion ratio is within a range from 0.5 to 0.9. Further, an exhaust valve is not temporarily opened in a compression stroke first stage, at a time of starting or driving under a low load, and the Atkinson cycle in accordance with the re-opening of the exhaust valve is achieved at a time of driving under a high load.

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 may be formed of plates and joint pins, to form a link chain or a roller chain, for instance, and it is movably connected to the valve control member in the plane perpendicular to the axis of rotation of the cam element.

Abstract: An internal combustion engine has a valve train and decompression mechanisms disposed in a valve chamber, and a fuel pump attached to a cylinder head. A pump cam for driving the actuating rod of a fuel pump through a swing arm, and a decompression mechanism opposite an end journal relative to the pump cam with respect to an axial direction parallel to the axis of the camshaft are formed on the camshaft in the valve chamber. One of the decompression mechanisms is disposed between the pump cam and an exhaust cam. The swing arm has a contact tip in contact with the pump, cam and a pushing tip in contact with the actuating rod at a position nearer to the exhaust cam than the contact part with respect to the axial direction. The pump cam comes into contact with an end bearing supporting the camshaft to restrain the camshaft from axial movement.

Abstract: A variable valve actuation (VVA) mechanism includes a partial wrap output cam assembly and a partial wrap frame assembly. Each of the partial wrap cam assembly and the partial wrap frame assembly include a respective body and a respective shaft engaging means coupled to the body. The shaft-engaging means are configured for engaging an input shaft with a snap fit to thereby pivotally dispose the output cam assembly and the frame assembly upon the input shaft.

Abstract: System uses a method of securing a cam to a rotatable shaft in a discrete angular position with respect to the shaft. The device uses leaf springs along the inside diameter of the cam to lock individual sets of cam teeth to the shaft splines. Circumferential placement of the cam teeth sets of the cam permit no more than one set of cam teeth to be fully engaged with a shaft at any one time. This provides smaller and more numerous possible incremental angular positions of the cam with respect to the shaft while the remaining partially engaged sets of cam teeth provide a locking normal force to secure the cam and the fully engaged cam teeth set onto the shaft.

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: A fuel pump for an engine may include a cylinder, a piston displaceably disposed in the cylinder, and a cam driven by the engine. The cam engages the piston to form a cam-follower mechanism so that the rotation of the cam generates a reciprocal movement of the piston inside the cylinder. The cam preferably includes a variable cam lobe having a maximum radius that is a function of engine speed so that the displacement of the piston generated by the variable cam lobe is a function of the engine speed. The cam may also include a weight that is subject to a centrifugal force when the ram is rotating. Alternatively, the maximum radius of the variable cam lobe may be a function of pump outlet pressure so that the displacement of the piston generated by the variable cam lobe is a function of the pump outlet pressure.

Abstract: A barrel engine has an engine housing with a first and second end. An elongated power shaft is longitudinally disposed in the engine housing and defines the longitudinal axis of the engine. A plurality of cylinders surround the longitudinal axis, with each having a closed end and an open end. Each cylinder has a central axis. The open ends of the cylinders are directed toward the first end of the housing. An intake system introduces a combustible mixture of air and fuel into each of the cylinders. A track is disposed between the first end of the housing and the open ends of the cylinders such that a portion of the track is disposed generally in alignment with the central axis of each of the cylinders. The track has a cam surface that longitudinally undulates with respect to the open ends of the cylinders. A portion of the cam surface is disposed generally in alignment with the central axis of each of the cylinders.

Abstract: An output cam for a variable valve mechanism includes a body configured for being pivotally associated with and driven by an input shaft. A lift profile of the output cam includes a base circle portion, a cam portion and a fixed radius portion. The base circle portion is adjacent to and continuous with the cam portion, and the cam portion is adjacent to and continuous with the fixed radius portion. The base circle portion has a base radius, the cam portion has a cam radius and the fixed radius portion has a fixed radius. The base and fixed radii are substantially constant. The fixed radius is a predetermined amount greater than the base radius. The cam radius increases from a value approximately equal to the base radius adjacent the base circle portion to a value approximately equal to the fixed radius adjacent the fixed radius portion.

Abstract: The invention relates to improved cam contacting devices for use in internal combustion engines and preferably for use in internal combustion engines having variable valve timing. In particular, the use of ceramics including silicon nitride and silicon carbide have been demonstrated as providing effective cam contacting surfaces allowing an axially displaceable cam shaft having a variable profile cam to be run with resulting improvements in idle speed and volumetric efficiency.

Abstract: The present invention provides a thrust cam cap for an engine camshaft disclosed to effectively place a thrust cam cap to limit the longitudinal movement of an engine camshaft according to the location of a thrust bearing cap that limits the longitudinal movement of the crankshaft, thereby maintaining a smooth operation of a timing belt or a timing chain in spite of thermal expansion of the crankshaft and the camshaft while an engine is in operation.

Abstract: In a valve-operating assembly of a driven rotation member and a cam, including a hub rotatably carried on a support shaft, a cam formed on an outer periphery of one end of the hub, and a driven rotation member coupled to one end of the cam; the cam and the hub are integrally formed of a sintered alloy; the cam has a recess defined in one end face thereof; and the driven rotation member is made of a synthetic resin, and mold-coupled to the cam and the hub so that the recess is filled with the synthetic resin of the driven rotation member and an outer periphery of the hub is wrapped with the synthetic resin. Thus, it is possible to provide the valve-operating assembly of the driven rotation member and the cam, which is lightweight and excellent in lubrication of the cam and the hub.

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 camshaft assembly and method of making a camshaft assembly is disclosed. Each of the cams includes a lobe boss portion that defines the cam lift profile, and a base portion that provides a surface for joining the cam to the shaft. In contrast to conventional ring-type cams, the base portion of the cam does not circumscribe the outer surface of the shaft, but instead extends only part way around the circumference or periphery of the shaft. This allows for radial mounting of the cams at virtually any timing angle, and permits the use of simple techniques for joining the cams to the shaft, including capacitance discharge welding. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

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 variable valve actuation assembly (41) to be mounted about a camshaft (43) including a concentric portion (47) and an eccentric portion (49) which orbits the axis of rotation (A1) of the camshaft and defines an axis (A2). The assembly (41) includes a secondary cam member (51) surrounding the concentric portion (47) and including a cam surface (59,59L). The assembly (41) also includes an arm assembly (61) which surrounds the eccentric portion (49), and defines a longitudinal axis (A3) perpendicular to, and intersecting the axis (A2). The arm assembly (61) can pivot about a pin (71), and at the opposite axial end is pivotally connected to the secondary cam member (51) by means of a pin (75). Rotation of the camshaft (43) causes the arm assembly (61) to pivot about the pin (71) in one direction, rotating the cam member (51) to lift the valve (17), then pivot in the other direction, rotating the cam member (51) in the opposite direction.

Abstract: An assembled camshaft (10) for engine includes: a cam lobe piece (12); and a hollow shaft member (11) having at least two shaft fixing surfaces (11A) formed by plasticity process on a portion of the hollow shaft member (11) corresponding to a position between cylinders of the engine.

Abstract: A hollow camshaft (19) lubrication system for aircraft engines that supplies lubricant (14) to cam lobe surfaces (25) from the interior surface (22) of the hollow camshaft (19) even during periods when aircraft operation moves the rotation axis of the hollow camshaft (19) from horizontal.

Abstract: For a peripheral cam for a valve-controlled internal-combustion engine, having a cam contour which generates at least one positive acceleration course in the valve opening area, the gas dynamics, are advantageously influenced in that the peripheral cam has an opening flank with a contour causing a delayed opening acceleration course. The opening acceleration course is generated with acceleration curves with relatively high acceleration peak values of different amounts spaced by way of an intermediate curve of relatively low positive acceleration values. A first acceleration curve has a peak value of approximately 40 to 60% of a peak value of an adjacent acceleration curve set at 100%.

Abstract: An accumulator 114 is provided in an engine 7 camshaft 73 having at least one lobe and an internal cavity 170. A compliance member 174 is provided for pressurizing the fluid within the internal cavity 170.

Abstract: A desmodromic valve actuation system for opening and closing at least one valve of an engine having a cam assemblage and a driving mechanism for reciprocal movement operably connected to said cam assemblage. The cam assemblage includes a cam mechanism for rotational movement and the driving mechanism also being operably connected to the at least one valve of the engine to move the at least one valve between a valve closed position and a valve open position and between the open position and the closed position in a manner directly related to the rotational movement of the cam mechanism. In addition, a mechanism is provided for adjustably controlling the movement of the at least one valve in order to provide a variable amount of opening of the at least one valve in the open position. The opening and closing of the at least one valve takes place without the intervention of a spring action.

Abstract: The cams (2) of the inventive camshaft, which is configured from an assembly of individual parts, are provided with foot strips (2.2, 2.3) that border the shaft (1). Said cams are welded to the shaft along and through these foot strips. This produces a weld joint (3.1) with a virtually optimal weld cross-section (3.1), whose width corresponds approximately to the width of the foot strips and thus produces an extremely good joint overall which is strong and permanent. As the shaft and the cams are put under only minimal strain by the welding process, they can be machined almost to their final dimensions before being assembled. The cams can be welded efficiently to the shaft in one single time-saving work operation.

Abstract: A mechanism for operating one or more valves of a piston device, in particular an intake or exhaust valve of an internal-combustion engine, which valve can move between an open position and a closed position and is provided with associated restoring means for returning the valve to the closed position. The mechanism comprises a hydraulic valve actuator for operating the valve of the piston device, which valve actuator has a variable chamber which is delimited by a piston which can be coupled to the valve, in such a manner that when hydraulic fluid is supplied to the said chamber the valve opens. Furthermore, there are rotatable first and second cams, each having an associated cam follower, the relative angular position of the first cam and the second cam with respect to one another being adjustable.

Abstract: A modular camshaft assembly having an elongated shaft, at least one cam lobe assembly, at least one spacer assembly, and a cam adapter assembly is disclosed. 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: Camshaft configurations are increasingly more closely assembled in motor vehicle engines such that access to the cylinder head bolts is obstructed. Indentations 2 along built-up camshafts, which comprise a camshaft tube 1 with slid-on camshaft structural components, such as the cams 3, permit through corresponding rotation free access to the cylinder head bolts even after they are in the installed state. In order to be able to employ for the camshaft structure tubular camshafts 1, according to the invention a pressing tool 10 with bottom dies 12, 13 is provided such that during the pressing operation of the indentations, the camshaft tube 1 advantageously is not deformed beyond the original outer diameter d and the camshaft 1 can be assembled advantageously form-fittingly through subsequent sliding-on of the cams 3.

Abstract: A swing cam to actuate engine valves is rotatably disposed about a drive shaft. A first eccentric cam is tightly disposed on the drive shaft. A ring-link is rotatably disposed on the first eccentric cam. A second eccentric cam is tightly disposed on a control shaft which rotates to a given angular position in accordance with an operation condition of an associated internal combustion engine. A rocker arm is rotatably disposed on the second eccentric cam. A rod-link extends between the rocker arm and the swing cam. A first connecting pin pivotally connects a first arm portion of the rocker arm with the ring-link. A second connecting pin pivotally connects a second arm portion of the rocker arm with an end of the rod-link. A third connecting pin pivotally connects the other end of the rod-link with the swing cam. The first connecting pin is fixed to either one of the first arm portion of the rocker arm and the ring-link.

Abstract: The invention concerns an electrically rotatable adjusting shaft (1) of a fully variable mechanical valve train of an internal combustion engine, said adjusting shaft comprising an adjusting cam. A rapid and exact rotation of the adjusting shaft (1) and the load regulation of the internal combustion engine depending thereon is achieved by the fact that an actuator (3) for rotating the adjusting shaft (1) comprises an adjusting lever (4) that is connected rotationally fast to the adjusting shaft (1), and the free end of the adjusting lever (4) can be loaded by a cam plate (6) that is driven by an electromotor (7).

Abstract: A VVA apparatus for an internal combustion engine includes a intake valve, and an alteration mechanism which variably controlling lift characteristics of the intake valve in accordance with the engine operating conditions, wherein the valve lift characteristics include a ramp period which is shorter in the range of medium lift amount than in the range of small lift amount and the range of large lift amount.

Abstract: An engine has a combustion chamber. An air induction system communicates with the combustion chamber through an intake port. An exhaust system communicates with the combustion chamber through an exhaust port. Intake and exhaust valves move between an opening position and a closing position of the intake port and the exhaust port, respectively. A camshaft actuates either the intake valve or the exhaust valve. The camshaft extends generally vertically. A camshaft cover member encloses the camshaft together with an engine body of the engine. The camshaft cover member defines a slot through which a tool can pass. The tool can prevent the camshaft from rotating.

Abstract: In a valve-operating assembly of a driven rotation member and a cam, including a hub rotatably carried on a support shaft, a cam formed on an outer periphery of one end of the hub, and a driven rotation member coupled to one end of the cam; the cam and the hub are integrally formed of a sintered alloy; the cam has a recess defined in one end face thereof; and the driven rotation member is made of a synthetic resin, and mold-coupled to the cam and the hub so that the recess is filled with the synthetic resin of the driven rotation member and an outer periphery of the hub is wrapped with the synthetic resin. Thus, it is possible to provide the valve-operating assembly of the driven rotation member and the cam, which is lightweight and excellent in lubrication of the cam and the hub.

Abstract: A baffle for use in an interior of a cam cover and a method of making the baffle are disclosed. The baffle includes a structural layer, which is made of metal, and an isolation layer that is made of a resilient foam. The isolation layer is disposed on a surface of the structural layer in a pattern that leaves uncovered a portion of the surface of the structural layer. When the baffle is installed in the cam cover, the isolation layer provides an interface between the structural layer and the cam cover, which isolates the baffle from vibrations in the cam cover. Since the isolation layer is applied only where it is needed, the disclosed baffle and process use less material.

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.