Abstract: An anti-rolling motion control system for an automotive vehicle is provided. This control system comprises shock absorbers each being variable of a damping coefficient within a range from softer to harder damping characteristics, a steering sensor for monitoring a steered angle of a steering wheel, and a rolling motion control unit. The rolling motion control unit is operable to derive steered angular velocity based on the steered angle of the steering wheel. The rolling motion control unit controls the shock absorbers so that the damping coefficients are modified to exhibit the harder damping characteristics when the steered angular velocity and the steered angle are greater than preselected first and second threshold values respectively for suppressing rolling motion of a vehicle body effectively while securing traveling stability.

Abstract: There is disclosed a damping force controller for controlling a damping force characteristic of a damper disposed between an unsprung mass and a sprung mass of a vehicle. A control unit repeatedly compares an output signal of a load sensor with a predetermined range. After the sensor output signal has been kept deviated from the predetermined range over a predetermined period of time longer than a resonance period of the unsprung mass, a damping force of the damper is increased for enhanced stability of the vehicle.

Abstract: An oil pump comprises a housing, a cover, an inner gear having external teeth and a recess, and an outer gear having internal teeth engaged with the external teeth of the inner gear. The housing or the cover includes an engagement protrusion to be engaged with the recess of the inner gear for supporting the inner gear during assembly.

Abstract: A control system for a damping force coefficient of a shock absorber for a vehicle suspension provides a controller for correcting the position of a step motor. The controller sets the step motor at a predetermined position in a manner to intermittently move the step motor to a stop position restricted by a stopper and to reversely rotate it by a predetermined number of steps. Therefore, the step motor is precisely set at a home position without using a position detector.

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: A hydraulic damper is disclosed which has a contraction phase one-way passage way which allows a flow of damping fluid in contraction phase, an extension phase one-way passage way which allows a flow of damping fluid in extension phase, and a valve element in the form of a hollow control rod. The valve element has a neutral position in which both of the contraction phase and extension phase one-way passage ways are open, a first displaced position in which the extension phase one-way passage way is restricted with the contraction phase one-way passage way left open, and a second displaced position in which the contraction phase one-way passage way is restricted with said extension phase one-way passage way left open.

Abstract: An aluminum-silicon alloy having excellent mechanical characteristics is formed by pressure casting of a molten material concurrently with modifying thereof by a flux which includes at least one element selected from the group of Na, Sb, Sr, and/or Ca, allowing a substantially fine grain of silicon to be dispersed in the alloy. Alternatively, the step of the pressure casting is replacable by substantial uniform cooling of the molten material regardless of a thickness thereof by cooling a die having a mold formed of a Cu-W type material, which mold corresponds to a substantially thick portion of the alloy.

Abstract: An apparatus for actuating valves of an engine is disclosed. A cam shaft is supported by the engine and has at least one set of cams, e.g., two axially spaced low speed cams and a high speed cam between the low speed cams. A rocker shaft is supported by the engine. The rocker shaft supports a rocker arm for the valves. The rocker arm is driven by the low speed cams. The rocker arm has a sub-rocker shaft and a pin. A free cam follower is supported by the sub-rocker shaft and driven by the high speed cam. The apparatus comprises a mechanism including a lever supported by the pin of the rocker arm. The lever has a first position wherein the lever and the free cam follower are joined for attaining unitary motion of the free cam follower with the rocker arm. The lever has a second position wherein the lever and the free cam follower are separated for allowing relative motion of the free cam follower with respect to the rocker arm.

Abstract: An electromagnetic suspension device for use between a vehicle body and a road wheel is disclosed, which comprises a body-connected structure connected to the vehicle body to move therewith and a wheel-connected structure connected to the road wheel to move therewith. The body-connected and wheel-connected structures are arranged to carry out a relative movement therebetween. An electromagnetic actuator is associated with the body-connected and wheel-connected structures in order to electromagnetically control the relative movement in accordance with electric power applied thereto. A hydraulic damper is arranged in parallel with the electromagnetic actuator between the body-connected structure and the wheel-connected structure to produce a damping force in accordance with the relative movement.

Abstract: A variable damping characteristics shock absorber includes a piston provided with first and second disc valves. Within a piston, an annular space is defined between the first and second disc valves. The annular space is selectively communicated with upper and lower fluid chambers defined in a shock absorber cylinder tube via a by-pass path. A variable orifice formed by means of a rotary valve is provided in the by-pass path.

Abstract: A system and method for controlling a damping force for a vehicular damper is disclosed in which the damper is provided with a damping factor adjusting mechanism which is installed for adjusting the damping force characteristic at a plurality of stages. When both directions of a vertical velocity of an sprung mass (vehicle body) and of a relative velocity between the unsprung mass and sprung mass coincide with each other, a controller outputs a control signal to the damping factor adjusting mechanism so that the damping force characteristic of the damper is changed to a higher damping force side, provided that the relative velocity exceeds a predetermined dead zone. In addition, when both directions do not coincide with each other, the controller outputs the control signal so that the damping force characteristic is changed to a lower damping force side.

Abstract: A method of and a system for controlling a hydraulic shock absorber of an automobile are provided. In the shock absorber, a flow of damping fluid induces a load on an actuator of the shock absorber during bouncing and rebouncing of the shock absorber, and the actuator is actuated in response to an output signal of a control unit. In order for the actuator to counteract the load applied thereto, the output signal is modified in response to the load. According to the embodiment, the load is determined by a table look-up operation based on an input load detected by a load sensor mounted to the automobile.

Abstract: In a pressure control valve, a filter member is disposed in a feedback path for feeding back fluid pressure in the corresponding control port to a pilot chamber for feedback controlling a position of the valve spool in cooperation with an electric or electromagnetic actuator. The filter member is so arranged as to remove foreign matter. The filter member also serves for regulating fluid flow in the feedback path.

Abstract: A multiple electromagnetic valve comprises a yoke and a port structure held by the yoke. The structure has therein a chamber from which two passages extend to the outside. Two electromagnets are mounted on the yoke, and two armatures for use with the electromagnets are pivotally supported by the yoke. The armatures are pivoted in a first direction when the electromagnets are energized. Springs are employed for biasing the armatures to pivot in a second direction which is opposite to the first direction. Two valve bodies are respectively held by the armatures and arranged to close terminal ends of the passages when the armatures are pivoted in the first direction.

Abstract: A shock absorber is provided a piston stroke speed dependent linear variation characteristics of damping force. The shock absorber includes variable orifices in tandem fashion for achieving linear variation characteristics of damping force according to variation of the piston stroke. One of the variable orifices is provided with variation characteristics of flow restriction for a greater variation rate of the damping force in a low piston stroke speed range, and the other is provided variation characteristics of flow restriction for a greater variation rate of the damping force in the intermediate and high piston stroke speed range. The variable orifice may be provided in a piston assembly or in the alternative in a bottom fitting in the case of a double-action type shock absorber.

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: An electromagnetic strut comprises a coil assembly including a plurality of coils arranged along a predetermined axis, and a magnetic device movable relative to the coil assembly along the predetermined axis. The magnetic device includes a magnetic circuit which produces two magnetic fields spaced at a distance along the predetermined axis, Each of the plurality of coils has an axial dimension less than the distance at which the two magnetic fields of the magnetic circuit are spaced.

Abstract: A pressure control valve assembly is provided with a valve spool which is formed integrally with a plunger of an electromagnetic solenoid so that the electromagnetic force generated by the solenoid is directly active on the valve spool. By integration of the valve spool and the plunger of the solenoid, axial length can be reduced. Furthermore, with this construction, the set springs can be axially oriented outside of the solenoid to make it easy to adjust the set load to be exerted on the valve spool.

Abstract: An oil pump comprises a pump casing, a crankshaft, an inner rotor mounted on the crankshaft, an outer rotor, an intake chamber, and a discharge chamber. The inner rotor has outwardly projecting teeth which engage with inwardly projecting teeth of the outer rotor for rotating the outer rotor for transferring oil from the intake chamber to the discharge chamber. A stopper is provided which contacts edge portions of the teeth of the inner and outer rotors respectively to prevent oil in a space between the teeth from leaking.

Abstract: A variable intake- and/or exhaust-valve timing control system for an internal combustion engine comprises a cam sprocket having a driven connection with an engine crankshaft, a camshaft, a ring gear provided between the camshaft and the cam sprocket for adjusting a relative phase angle between the cam sprocket and the camshaft, and a ring gear drive mechanism for drivingly controlling the ring gear via fluid pressure created by an engine oil pump, depending upon the operating state of the engine. The drive mechanism includes a subsidiary oil pump for supplying a fluid pressure greater than a designated pressure level to the ring gear, during low engine speed and high engine load.