Abstract: A device for the continuous variation of a relative angular position between a crankshaft and a camshaft of an internal combustion engine comprising a drive element (2) driven by the crankshaft of the internal combustion engine through a traction means, a sliding sleeve (7) which is positively locked by a first gearing (8, 9) to the drive element (2) and by a second gearing (10, 11) to a driven element (13), and an adjusting piston (6) which is fixed on the sliding sleeve (7) and guided in a housing (3) to axially delimit two pressure chambers (14, 15) which are sealed from each other by a sealing arrangement whereby a radially inward oriented sealing of the sliding sleeve (7), is achieved by providing a sealing disc (17) of continuous configuration which bears against an inner wall (19) of the sliding sleeve (7).

Abstract: According to the present invention, in a valve timing adjustment device, an arc-shaped gears are assembled alternately on a piston in the peripheral direction. A spring biases an annular member and the arc-shaped gear in the direction as to be away from the piston. A pin is press-fitted into a retainer ring. A spring biases the arc-shaped gear toward the retainer ring, that is, in the direction as to be closer to the piston. An annular member, an annular groove, the head of the pin, a cap, and a containing hole function as a hydraulic damper, respectively. Accordingly, the collision speed of the annular member with the piston accompanied by the movement of the arc-shaped gears, and the piston and the collision speed of the head of the pin with the piston are slowed down. In this way, the respective collision noises can be reduced.

Abstract: A phase changing mechanism is disclosed which is applicable to a valve gear of a dual overhead camshaft internal combustion engine. The mechanism comprises a driving shaft, a cam rotatable relative to the driving shaft, a drive member fixed to the driving shaft, a driven member integral with the cam, a support, an intermediate member rotatablly supported in an eccentric circular cam integral with the support, a first coupling coupling the drive member with the intermediate member at a first position spaced from an axis of the driving shaft, and a second coupling coupling the driven member with the intermediate member at a second position angularly spaced from the first position with respect to the shaft axis. The first coupling has a movable connection with the intermediate member to permit variation in a distance of the first position from an axis of rotation of the intermediate member during operation.

Abstract: A planetary cam phaser for varying the timing of an engine camshaft is provided with oppositely tapered teeth on the planet gear(s) and the mating ring and sun gears and biasing means for urging the mating gears axially into lash free engagement. The tapered teeth may be formed on constant pitch circles or on conical pitch circles of conical gears and the teeth of at least one of a pair of mating gears may be crowned to control loading and wear. The taper angles of the teeth and/or the conical pitch circles of the conical gears are preferably made small enough to avoid gear drive forces from developing gear separation forces greater than restraining friction forces.

Abstract: A planetary cam phaser includes an electric motor driven worm gear actuator for rotatably positioning a sun gear to vary the cam phase relative to the crankshaft of an associated engine. Preferably, the worm lead angle is made small to lock the actuator against back driving by camshaft generated forces so the phaser is actuated only by controlled motor movements. Alternatively, a return spring may be applied on the motor or worm shaft to return the phase to an initial position when the motor is de-energized or fails. In another version, the worm lead angle may be increased to permit limited back driving forces to drive the cam back to the initial position when the motor is off without the need for a return spring.

Abstract: A camshaft timing device includes a camshaft 10 and a drive gear 20 rotatably mounted thereon. An interconnecting shifting shaft 30 has spline 31 and 33 that interconnect with respective splines 16 and 41 on the camshaft and a hub of a drive gear 20. Axial movement of the shaft 30 causes the shaft to rotate the camshaft 30 with respect to the drive gear 20 due to the helical nature of the splines 33 and 41. The axial movement of the shaft 30 is caused by a drive sleeve 50 connected to a pinion gear that is driven through a worm gear 63 by an electric motor 67.

Abstract: A valve timing control system for an internal combustion engine includes a valve timing varying mechanism having a camshaft for driving an intake or exhaust valve, a hydraulic piston for varying an angular phase of the camshaft relative to an engine crankshaft, and valve timing advancing and retarding hydraulic pressure chambers for determining a position of the hydraulic piston. The valve timing control system further includes a control valve for controlling hydraulic pressures to be applied to the hydraulic pressure chambers. The control valve includes a sleeve and a spool slidably received in the sleeve. The sleeve is formed with a plurality of openings which, in cooperation with the spool, selectively establish and prohibit communication of the hydraulic pressure chambers relative to high and low pressure sides. Each of the openings is in the form of a groove and extends partially along the circumference of the sleeve.

Abstract: Angular phase of a cam shaft of an internal combustion engine is adjusted by changing angular position of a vane rotor in a shoe housing. Each of vanes 2 has a couple of a check valve and a pilot valve which are moving members moving in parallel with the rotation axis to switch on and off oil passages. Since the moving members move in parallel with the rotation axis, the motion thereof is not affected by the centrifugal force caused by the rotation. Further, since the moving members are accommodated inside the vanes, sealing between advancing chambers and retarding chambers which are disposed opposite sides of the vanes can be ensured without increasing the size, particularly the outer diameter, of the device.

Abstract: A valve timing adjusting mechanism for an internal combustion engine includes an internal gear mounted on either one of a crankshaft or a cam shaft of the engine for rotation therewith, an external gear assembled in surrounding relationship with the internal gear, the external gear being driving connected to the other one of the crankshaft and camshaft for rotation therewith, and an intermediate gear set disposed in an annular space between the internal and external gears to be moved by fluid under pressure applied thereto in an axial direction for effecting relative rotation of the internal and external gears.

Abstract: One of the driving and driven parts of the coupling is connected to a cylinder (10) and the other to a piston (11) which delimit therebetween two antagonistic chambers (13, 14). The chambers have a substantially constant volume, are filled with a practically incompressible hydraulic liquid, and are interconnected through two unidirectional circuits (18, 19) which have opposite directions and each a substantially constant volume. A distributing device (22) is so arranged as to either bring into action one or the other of the unidirectional circuits, or to neutralize both of them.

Abstract: A valve timing control device includes an input member to which a driving force is applied thereto, an output member having on its axis a cam for opening and closing a valve, a transmission member for transmitting torque between the output member and the input member and for changing the rotational position of the output member in relation to the input member in accordance with the position thereof, a slit member provided with a helical slit and secured to the input member and a passive member provided with a helical spline superposed with the helical slit of the slit member and secured to the output member. A base portion which is allowed to engage the helical slit of the slit member and a toothed portion which is allowed to engage with the helical spline of the passive member are formed in the transmission member so that the slit member is connected to the passive member via the slit member.

Abstract: An electronic timing system for controlling the injection angle of a fuel pump, comprising an input sleeve (12), an output drum (36), an intermediate drive sleeve (30), a drive plate (60), a drive yoke (76), and a stepper motor (90). Drive sleeve (30) includes a pair of radially inwardly and outwardly projecting drive pins (32), and drum (36) and input sleeve (12) both include helical slots (38) and (16), respectively, through which pins (32) project. Vertical movement of yoke (76) causes axial movement of drive plate (60) and drive sleeve (30), which causes a relative rotational adjustment of angle between input sleeve (12) and output drum (36), for retarding and advancing the timing of the fuel injection system.

Abstract: The electrohydraulic adjusting device for actuating a device for adjusting at least one camshaft of an internal combustion engine relative to its crankshaft has two differential pistons each of which serves to adjust a camshaft (intake camshaft or exhaust camshaft). Each of the two differential pistons have a small effective piston surface which is acted upon with pressure by a pump. An independent pressure control valve is associated with each of the pressure chambers on a larger effective piston surface, via which valve, the pressure in this pressure chamber can be controlled independently of the other differential piston.

Abstract: A device (1) for adjusting valve timing in an internal combustion engine, disposed within a control gear of at least one camshaft on a drive pinion (3) which is in driving relationship with this camshaft, said device (1) comprising an adjusting piston (2) which is axially displaceable by a hydraulic medium and whose first and second end faces (11,12) delimit a first and a second pressure chambers (13,14) while a peripheral surface (15) of the adjusting piston (2) bears sealingly against a housing (16) which delimits the first and the second pressure chambers (13,14) radially outwards, the adjusting piston (2) comprising two oppositely oriented helical gear sections, (6,7) and first (6) of said two helical gear sections cooperates with a corresponding gear (5) of a driving element (4) connected to the drive pinion (3), while second (7) of said two helical gear sections cooperates with a gear (8) of a driven element (9) connected to the camshaft, a stop element (18,19) or an end portion of the housing being arr

Abstract: A variable camshaft phase changing device has an annular piston and lash take up front and rear gears with inner and outer helical spline for phase changing and a return spring for the piston. The annular piston is maintained in drive relation with the front and rear gears in such a manner as to relieve lash take-up friction on the piston stroke against the return spring and on the piston return stroke.

Abstract: A variable cam phaser has drive and driven members connected by helical splines of an annular phase control piston and a lash control piston, axial motion of which varies the angular phase relation between the drive and driven members. A single wave spring received in a groove in one of the pistons biases them apart to take up lash in the splines. A return spring biases the phase control piston to an initial phase setting. Pre-timing of the members is provided for by a driven (or drive) member comprising two components, a hub flange that supports the other member and a splined hub carried by and initially rotatable on a tubular protrusion of the hub flange. After assembly of the phasing mechanism, the hub is rotated on the hub flange to pre-time the initial phasing of the members. An end of the tubular protrusion is then deformed into a flange engaging an annular shoulder on the hub to lock the hub and hub flange members together and maintain the pre-timing.

Abstract: A camshaft phase controller for an internal combustion engine controls separate intake and exhaust camshafts driven by the engine's crankshaft such that the angular phases of the camshafts may be varied by different amounts from a predetermined phase relationship with the crankshaft.

Abstract: A variable valve timing system includes helical splines to effect a relative rotation between an input member and an output member. The output member drives an intake and an exhaust valve against the urging force of a valve spring. The valve spring gives an undesired torque to the output member. The helical splines have backlash and the undesired torque causes a hitting noise. Therefore, a guide depression filled with viscous fluid is formed in front of the input member and a projection located and moved in the depression is formed in front of the output member. The depression and the projection with the viscous fluid form a damper to absorb the undesired torque.

Abstract: A phase change mechanism is described for varying the phase of an engine camshaft relative the engine crankshaft.

Abstract: A hydraulic system with a hydraulic pump driven directly by an internal-combustion engine reduces the dimension, weight and number of component parts used in the state of the art systems while optimizing energy exploitation. A plurality of elements, one of which is a cam shaft adjusting device, are supplied with hydraulic pressure fluid by one and the same pump. A series of simplified hydraulic connections enables equivalent devices to be driven simultaneously by one or more pump circuits.

Abstract: In a valve timing control device, when a camshaft is retained relative to a timing pulley, a hydraulic piston is applied with a force which moves it in a direction toward an advancing-side hydraulic chamber (i.e., in the direction to vary a valve timing to a delaying side) owing to reaction of the driving torque of the camshaft. This force causes fluid to leak out of the advancing-side hydraulic chamber, and the hydraulic piston is liable to move toward this hydraulic chamber. However, fluid of an amount corresponding to an amount of this leakage is supplied to the advancing-side hydraulic chamber by way of a control valve. Also, discharge of fluid from a delaying-side hydraulic chamber via the control valve is stopped. Thus, the movement of the hydraulic piston toward the advancing-side hydraulic chamber when the hydraulic piston is retained at a desired position is prevented. Therefore, the hydraulic piston can be stably retained at the desired position, and a desired valve timing can be maintained.

Abstract: A device for angular adjustment between at least two shafts, a crankshaft and a cam shaft, in driving relationship in an internal combustion engine, comprising an adjusting element arranged in a region of a cylinder head and connected to the camshaft while being arranged in an axial direction thereof, the adjusting element comprising a piston which is displaceable between two substantially circular ring-shaped pressure chambers which are connected to a source of pressure medium, characterized in that a separate oil distributing element (16) is rigidly integrated in a cap (27) of the adjusting element (3) arranged at a front end of the camshaft (5) and said oil distributing element (16) comprises ducts (6,7) for pressure medium supply oriented towards the piston (14) which comprises two piston areas of identical dimensions.

Abstract: The device for the relative rotation of the shaft of an internal combustion engine with respect to the drive wheel, which is rotatably arranged on the shaft, has a hydrostatic pump whose housing is torsionally securely connected to the camshaft. Within the drive wheel and the pump, there is an electromagnetically actuable control valve which controls the pressure medium connections between the pumps and the setting device (rotary piston control), i.e. it subject the pressure spaces to pressure or relieves them, so that the camshaft is correspondingly rotated relative to the drive wheel. The electromagnet of the control valve is actuated by means of a control unit influenced by sensors. The pressure medium supply to the setting device takes place via a hole in the camshaft. A very compact adjusting device for the camshaft is achieved in this way.

Abstract: A variable cam phaser (VCP) is disclosed in various modifications. The VCP includes a piston responsive to pressure in a fluid chamber having an inlet orifice and a plurality of outlets including a first outlet and a plurality of second outlets. A valve slide is movable to cover said second outlets one after another to pressurize the fluid chamber to displace the piston against a return spring. Outer and inner splined slides are drivingly mated with an internal helical spline of a cylindrical body secured to a sprocket and an external helical spline of a stub shaft secured to a camshaft. The splined slides are disposed between the piston and the return spring. Thus, movement of the piston and splined slides assembly in response to pressurization or depressurization of the fluid chamber advances or retards the valve timing or phase angle of the camshaft relative to the sprocket.

Abstract: A timing variator which is constructed to provide at least three predetermined different relative angular settings of the camshaft and the timing system of an internal combustion engine; the variator comprises a piston actuator slidable inside a space against a spring as a pressurized fluid is delivered into a supply chamber thereof. When the piston is to be stopped at a position intermediate to two end-of-stroke positions, in order to obtain an intermediate timing setting, pressurized fluid is delivered behind the piston, thereby producing an additional thrust concurrent with the spring thrust and partly balancing out the pressure of the medium being delivered into the supply chamber.

Abstract: An apparatus and method effects the cyclical actuation of an actuation member. The apparatus can be driven by a crankshaft and has at least one dual-acting phasing apparatus with at least three rotatable mounted internally splined members and at least a first rotatably mounted, externally splined, flexible member having a portion thereof rotatably disposed within each of at least two of the internally splined members. One inner splined member can be connected nonrotatably to a first rotatable member such as an inner shaft, which is rotatably disposed within an outer shaft of a concentric camshaft. Another internally splined member can be nonrotatably connected to the outer shaft. Yet another internally splined member can be nonrotatably connected to a pulley wheel driven by the crankshaft. A fourth internally splined member can be connected to one of the other three internally splined members.

Abstract: A device for transmitting torque between two rotatable shaft members (2, 3) in a stationary housing (1) contains a number of alternate clutch discs (10, 11) engageable to counteract differential rotational speed between the two shaft members, to which they are connected, a hydraulic clutch piston (12) to engage the clutch discs and a hydraulic pump arrangement (15-24) driven by the speed differential between the two shaft members. An annular control piston (15) is axially movably arranged in the housing and is in contact with control pins (17), which are rotatable together with one of the shaft members (3) and cooperate with a cam curve (20) in the other shaft member (2) in such a way that the control pins and thus the control piston are imparted an oscillating movement with a frequency directly proportional to the rotational speed differential between the two shaft members.

Abstract: A power steering system for automobiles comprising a rotary, driver-operated valve which is adapted to control pressure distribution from a steering pump to power-assist fluid motors and to a set of transversely disposed fluid pressure reaction pistons and which responds to a reaction pressure to oppose steering valve motion whereby the relationship between pressure and torque developed by the steering system can be tailored to provide the optimum relationship between these variables so that a desired reduced steering torque is provided at low vehicle speeds and a greater steering torque is provided at high vehicle speeds.

Abstract: An internal combustion engine is equipped with a valve timing controller capable of minimizing the electric power consumption and frictional wear of elements. The valve timing controller can vary the valve timing of valves. A camshaft is moved axially forwardly or rearwardly by electrically energizing an outer solenoid clutch or a brake releasing solenoid, respectively. An axial movement of the camshaft results in a change in valve timing. With the exception of a transient period during which the valve timing is being varied, both the brake releasing solenoid and the outer clutch are electrically deenergized to thereby reduce the electric power consumption, and both of them are maintained out of contact with a displaceable disc 13 to thereby reduce frictional wear thereof.

Abstract: A hydraulic adjusting device for rotating a camshaft relative to its drive wheel which includes a coupling member, which cooperates with the drive wheel and with the camshaft via a pair of gear tooth systems, at least one of which is a helical gear. The coupling member is connected to an actuator, which is embodied as a single-acting cylinder. This singleacting cylinder is acted upon by pressure that is variable by a control valve. The restoration of the coupling member or of the actuator takes place only from the restoring moment upon the actuation of the valves of the engine by the camshaft.

Abstract: A device for changing the rotational position of a rotating, driven control shaft that controls the opening and closing of gas exchange valves of an internal combustion engine and is displaced via an electric motor and an interposed toggle lever arrangement having a downstream diagonal toothing arrangement for simplified displacement with minimal force and energy expenditures. The result is a simple, accessible, easy to maintain economical displacement drive for changing the rotational position of the control shaft in order to change the control times of gas-exchange valves in an internal combustion engine.

Abstract: A camshaft (326) has a vane (360) secured to an end thereof for a non-oscating rotation therewith. The camshaft also carries a timing belt driven pulley (332) which can rotate with the camshaft but which is oscillatable with respect to the camshaft. The vane has opposed lobes (360a, 360b) which are received in opposed recesses (332a, 332b), respectively, of the pulley. The recesses have greater circumferential extent than the lobes to permit the vane and sprocket to oscillate with respect to one another and thereby permit the camshaft to change in phase relative to a crankshaft whose phase relative to the sprocket is fixed by virtue of the timing belt (338) drive extending therebetween.

Abstract: A valve operation control system for an internal combustion engine having a cam-shaft and a crank-shaft has an adjusting device for adjusting a phase difference between the cam-shaft and the crank-shaft by being supplied with hydraulic pressure, a driving device integrated with the adjusting device and having an oil pump driven by the cam-shaft and a hydraulic pressure line between the oil pump and the adjusting device, and a hydraulic pressure control device disposed in the hydraulic pressure line for regulating the hydraulic pressure to be supplied to the adjusting device.

Abstract: Devices (10,110,150,200 and 250) include roller clutches for controlling rotational phase change of a camshaft between full advance and full retard positions and positions therebetween. Each of the devices includes sets of selectively operative rollers such as a set of rollers (36) for preventing phase retard and a set of rollers (34) for preventing phase advance. Devices (10,110,150 and 200) have pairs of rollers 36,34 acted on respectively by ramp surfaces (32d,32c) defined by a common flat surface. An annular member (32) defining ramp surface (32d,32c) is mounted with free play relative to an axis of the camshaft. Device (110) includes a splitter spring (112). Devices 150 and 200 include internal actuators (152,202).

Abstract: A means of varying both the opening and closing angle of internal combustion engine cam-operated valves by means of a mechanism which responds to the torque applied to the camshaft by the valve springs in such a way that the opening angle of the valves is retarded and the closing angle advanced and in which a means of inhibiting this operation can be incorporated.

Abstract: A hydraulic control device for the rotation of the camshaft of an internal combustion engine has a sprocket wheel which is driven by the internal combustion engine and connected with the camshaft via a couple member, a spiral toothing and a straight toothing, so that a relative rotation of the drive wheel and camshaft is effected by displacement of the couple member. The couple member is displaced via a hydraulic piston which is acted upon by a radial piston pump arranged in the control device, sucking pressure medium out of a pressure medium reservoir arranged in the engine, and feeding it to the pressure spaces at the piston via outlet valves. A pressure control valve which can be acted upon electromagnetically is connected to one of the pressure spaces and can be opened by corresponding actuation of the electromagnet so that the pressure space at the piston is relieved.

Abstract: An adjusting device for adjusting the relative angular difference between two rotating members having a guide arrangement between a driving member and a rotating follower. The guide arrangement will allow the rotating driver to perform relative axial movement relative to the rotating follower to change the relative axial and angular difference between the rotating driver and the rotating follower.

Abstract: A hydraulic control device for rotating a cam shaft of an internal combustion engine has a sprocket wheel driven by an internal combustion engine, a couple member engageable with a cam shaft and supported by one end of the sprocket wheel and engaging in a central bore hole of the sprocket wheel, a magnet valve arranged so that the couple member is axially displaceable by a liquid pressure controlled by the magnet valve to bring about a relative rotation of the cam shaft relative to the sprocket wheel, and a main piston acting on the couple member and arranged so that the liquid pressure acts on the main piston. A hydraulic body is mounted on the drive wheel, and an axial piston pump is arranged in the hydraulic body and has axial bore holes and a plurality of additional pistons which slide in the bore holes and having outer rounded portions which contact a wobble plate. Outlet valves are arranged at an outlet side of the bore holes and connected to a pressure space defined by the main piston.

Abstract: The invention relates to a transmission device between two coaxial rotating members (1; 10), of the type comprising a viscous-fluid coupling (11) with a driving element and a driven element, and control devices for modifying the operating characteristic of this coupling. It is defined, in particular, in that the control devices are incorporated into the transmission device and act as a function of the rotational speed of one the said members and as a function of a torque transmitted by the device. The control devices can comprise flyweights (21) which are rotationally integral with the member (1) and with the case (12) of the viscous-fluid coupling, these flyweights acting to modify the internal pressure in the coupling (11), via shuttles (27) and a sliding sleeve (8) which is displaced as a function of the torque transmitted between the sun gear (2) and the output shaft (10). This sliding sleeve can, for example, act on a plate (16) which modifies the spacing between the disks (14, 15) of the coupling.

Abstract: A valve timing control system for an internal combustion engine is provided. This system comprises a sprocket assembly connected to a crankshaft of the engine, a camshaft assembly connected to the sprocket assembly for driving intake and/or exhaust valves of the engine, a ring gear assembly disposed between the sprocket assembly and the camshaft assembly, and a fluid power source for providing fluid pressure to a pressure chamber to axially displace the ring gear assembly to vary a phase angle relation over a range of first to second phase angles. A fluid pressure supply and drain lines are defined in the system which communicates between the fluid power source and the pressure chamber and between the pressure chamber and a drain port of the system respectively.

Abstract: The arrangement of the present invention provides for the automatically controlled varying of the relative rotating position of shafts in an international combustion engine, for example, a camshaft relative to a crankshaft driving it. This will influence the valve timing of an internal-combustion engine. The arrangement has an intermediate timing gear which can be axially moved between two end positions and which engages by way of a helical external and internal toothing with a driving wheel and the camshaft. An annulus, such as a stationary bearing ring, is filled with an electroviscous fluid which, by means of the application of a voltage supplied by an electronic control device, causes an axial force for the adjustment of the intermediate timing gear. An electroviscous locking bearing, which is provided between the camshaft and the intermediate timing gear, holds the intermediate timing gear in any position between the two end positions.

Abstract: The hydraulic control device for rotating the camshaft of an internal combustion engine has a couple member constructed as a piston (25) connected with the sprocket wheel of the camshaft via a spiral toothing and with the camshaft via a straight toothing. A hydraulic body is mounted on at the camshaft and receives a radial piston pump which delivers the pressure medium required for the displacement of the piston. The pressure space is closed by a controllable pressure limiting valve. An electromagnetic valve controls a pressure medium flow to the piston bores of the radial piston pump and the pressure medium is delivered by an external pump. The sprocket wheel and camshaft are rotated relative to one another by the displacement of the piston.

Abstract: The invention provides a rotational phase adjustment device mounted on a rotation shaft and having a hydraulic chamber rotatable with this rotation shaft, in which operating fluid or oil can be supplied to the hydraulic chamber from a housing covering the rotational phase adjustment device. Also, the invention provides a rotational phase adjustment device which can be assembled easily, and particularly prevents damages to an oil seal, sealing a hydraulic chamber, when assembling the oil seal. A housing is attached to an engine to cover the whole of a valve timing control device, and a ring plate is secured to the housing by a bolt threaded into the ring plate from the outside of the housing, so that an oil seal mounted on an outer periphery of the ring plate is held in liquidtight sliding contact with a camshaft sleeve to form two oil passages respectively inside and outside of the camshaft sleeve.

Abstract: A control mechanism for shifting the rotational phase transmitted from an engine, and for controlling the timing of the intake and exhaust valves. A first gear mechanism integrally rotates with respect to a timing pulley, and has a set of inner peripheral gear teeth. A second gear mechanism integrally rotates with respect to a camshaft, and has a set of outer peripheral gear teeth. The number of gear teeth of the first gear mechanism is greater than that of the second gear mechanism. This gear ratio generates a rotational phase shift of the timing pulley with respect to the camshaft, in order to vary the opening and closing timing of the intake and exhaust valves. A drive means drives the first gear mechanism in order to vary the phase shift and to control the opening and closing timing of the intake and exhaust valves in accordance with the operating state of the engine.

Abstract: The camshaft tends to change in reaction to pulses which it experiences during its normal operation, and it is permitted to change only in a given direction, either to advance or retard, by selectively blocking or permitting the flow of hydraulic fluid, preferably engine oil, through the return lines (194,196) from the recesses (132a, 132b) by controlling the position of a spool (800) within a valve body (798) of a control valve (792) in response to a signal indicative of an engine operating condition from an engine control unit (808). The spool is centered during normal operation when the hydraulic loads acting on its opposed ends by the action of springs (802, 804) that also act on the opposed ends of the spool are in balance. During periods of operation when system pressure is low, a biasing mechanism forces the spool to its full advance position.

Abstract: For minimizing a diameter of an apparatus which is located on the cam-shaft and changes a phase between two cam-shafts, a variable valve timing system in an engine having first and second cam-shafts is comprised of a first gear rotatably supported on the first cam-shaft, a second gear fixed to the second cam-shaft, and geared with the first gear to transmit torque to the second cam-shaft, a first device for transmitting torque from the first cam-shaft to the first gear, and for rotating the first gear toward a first position, the first device being located on one end of the first cam-shaft, and a second means for rotating the first gear in a second direction opposite the first direction, toward a second position, the second device being located on one end of the second cam-shaft.

Abstract: A valve opening and closing timing control apparatus is disclosed, which includes an engine including a cam shaft and a crank shaft, a first sensor adapted for detecting rotary positions of the cam shaft, a second sensor adapted for detecting rotary positions of the crank shaft, a hydraulic pump driven by the crank shaft, a rotary phase varying means disposed on the cam shaft and adapted for varying rotary phases of the cam shaft, a hydraulic line connecting the hydraulic pump and the rotary phase varying means, a hydraulic control means disposed in the hydraulic line, an electronic control means adapted for controlling the hydraulic means and receiving output signals which are output by the first sensor and the second sensor at least, thereby operating the rotary phase varying means with the hydraulic control means under linear control.

Abstract: A valve timing phaseshifter between two members, such as a crankshaft driven housing and a driven camshaft member, that are hydraulically interconnected by fluid trapped in hydraulic cylinders containing plungers connected to the camshaft, relative movement between the cylinders and plungers providing the phaseshifting and being controlled by a valve that is axially movably mounted within the camshaft and hydraulically connected thereto by sets of helical grooves that are aligned or misaligned as a function of axial movement of the valve in response to the call for phase adjustment, the valve being movable from a neutral position to other positions in opposite directions to control the flow of fluid under pressure to the cylinders to cause the drive and driven members to rotate unitarily or for the camshaft to be advanced or retarded as the case may be, with respect to a conventional timing schedule.

Abstract: A valve timing control apparatus including a rotary member drivingly connected to an engine crankshaft for rotation with the engine crankshaft, and a drive mechanism for transmitting rotation of the rotary member to a camshaft. The drive mechanism includes a piston member provided for reciprocation between first and second positions within the rotary member to rotate the camshaft with respect to the rotary member. The piston member defines first and second pressure chambers on the opposite sides thereof along with the rotary member. A valve member is provided for movement between third and fourth positions. The valve member is adapted to connect the first pressure chamber to a pressure source while connecting the second pressure chamber to a drain port to produce a pressure differential between the first and second pressure chambers to move the piston member toward the second position when the valve member moves from the third position to the fourth position.

Abstract: A device for adjusting the control times on a control drive of an internal combustion engine, with a gear by the crankshaft of the internal combustion engine, the gear being located on a camshaft for actuating the gas shuttle valve, for which the camshaft can be adjusted relative to the gear over a limited range of angles of rotation. To achieve simple construction, the camshaft can be freely twisted relative to the gear over at least one specific angle of twist in both directions of rotation, and the camshaft is coupled to the gear.