Abstract: An electromagnetic drive system for repeatedly opening and closing a valve of an internal combustion engine is comprised of an electromagnetic drive mechanism and a damper mechanism. The electromagnetic drive mechanism comprises a pair of electromagnets, an armature disposed between the electromagnets and a pair of springs setting the armature at a neutral position between the electromagnets when both the electromagnets are de-energized. The electromagnets are alternately energized and de-energized according to a control signal. The damper mechanism is interlocked with the electromagnetic drive mechanism and functions to decrease a speed of displacement of the valve at a terminating period of each of a valve-closing stroke and a valve-opening stroke of the valve.

Abstract: A suspension control system for an automotive vehicle is disclosed in which a band pass filter is provided which passes only a frequency component of either of a vertical sprung mass acceleration signal derived from a vertical G sensor or a vertical sprung mass speed signal derived from an integrator which integrates the vertical sprung mass acceleration signal, both vertical acceleration sprung mass speed signal and vertical sprung mass speed signal falling in a predetermined frequency range (e.g., 0.5 Hz through 3.0 Hz). A control unit outputs a control signal to an actuator so to vary the position of an adjuster of each or any one of shock absorbers, thus a damping coefficient being set to a target damping coefficient position according to the vertical sprung mass speed.

Abstract: An anti-rolling control system for an automotive vehicle is provided. This control system comprises shock absorbers each disposed between a vehicle body and a suspension member rotatably supporting a wheel and being variable of damping force within a range from soft to hard 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 steering angular velocity based on the steered angle of the steering wheel to determine a transient status of vehicle rolling motion when the steering angular velocity is greater than a threshold value. When the vehicle is in the transient status of rolling motion, the damping forces of the shock absorbers are modified to suppress the rolling motion.

Abstract: A semiconductor type acceleration sensor comprises a flexible printed circuit board on which a semiconductor type detector chip section is mounted The detector chip is formed with openings therethrough overlapping an opening formed in a rear-side base plate of the flexible printed circuit board such that the detector chip section is supported only by a bridge portion. In case of excess input in an acceleration direction, elastic deformation of the bridge portion and a bending portion of the flexible printed circuit board provide absorption of tile excess input for protecting the detector chip section.

Abstract: A semiconductor type acceleration sensor comprises a flexible printed circuit board on which a semiconductor type detector chip section is mounted. The detector chip is formed with openings therethrough overlapping an opening formed in a rear-side base plate of the flexible printed circuit board such that the detector chip section is supported only by a bridge portion. In case of excess input in an acceleration direction, elastic deformation of the bridge portion and a bending portion of the flexible printed circuit board provide absorption of the excess input for protecting the detector chip section.

Abstract: A suspension control system for an automotive vehicle is provided. This suspension control system comprises variable damping force shock absorbers and a control unit which controls the shock absorbers to assume damping force characteristics in a range between preselected higher and lower damping coefficients. The control unit is operable to provide a control parameter indicative of bouncing motion of a vehicle body based on sprung vertical speed to determine a damping coefficient against the bouncing motion. When the control parameter is greater than a threshold value, the damping coefficient is modified to a lower value, while when the control parameter is less than the threshold value, the damping coefficient is modified to a higher value. With this damping coefficient modification, the bouncing motion is suppressed effectively while assuring passenger comfort.

Abstract: A suspension control system for an automotive vehicle is disclosed in which, in each shock absorber, interposed between the vehicular body and tire wheel, a damping coefficient varying adjuster is provided which changes a damping coefficient at either or both of piston stroke sides according to a control signal input thereto so that the damping coefficient is set to a target damping coefficient position, at lease one sprung mass acceleration sensor and at least one sprung mass speed sensor are provided, and the control unit is provided which outputs the control signal to the damping coefficient varying means according to a result of determination of whether the vertical sprung mass acceleration exceeds a predetermined threshold value and according to a direction and magnitude of the sprung mass speed so that the damping coefficient at either or both of the stroke sides is controlled to a target damping coefficient position.

Abstract: An automotive suspension control system employs a lateral acceleration sensor monitoring a lateral acceleration exerted on a vehicular body. The output level of the lateral acceleration sensor is processed to detect frequency of a occurrence of lateral acceleration magnitude greater than a predetermined threshold level within a predetermined period of time or a predetermined distance to travel. Judgement is made that the vehicle is on a rough road when the detected frequency becomes higher than or equal to a predetermined rough road criterion. The suspension control system, according to the present invention, is responsive to the judgement of rough road condition, to order softer suspension characteristics for satisfactorily suppressing vehicular body attitude change by absorbing vibration energy.

Abstract: A crankshaft assembly for an internal combustion engine includes a crankshaft, an elastic member fixed to the crankshaft, and a flywheel fixed to the elastic member such that the flywheel is supported in an elastic relationship with the crankshaft. The elastic member has a rigidity in its rotating direction large enough to effectively transmit a driving power to a transmission through a clutch. On the other hand, the elastic member has a rigidity in an axial direction of the crankshaft small enough to shift a resonance frequency of a bending vibration out of a target frequency band of a forced vibration, while ensuring to prevent a failure of disengagement of the clutch.

Abstract: An apparatus for controlling damping coefficients for respective vehicular shock absorbers is disclosed in which a plurality of shock absorbers are interposed between predetermined parts of a vehicle body and tire wheel and are provided with damping coefficient changing members, each changing member varying the coefficients of the damping shock absorbers at multiple stages by changing position of an associated actuator, the actuator receiving a signal to change the position of the damping coefficient changing member on the basis of an input signal derived from a sprung mass vertical G sensor. Particularly, a correction portion is provided in a control unit which varies a position change rate of the damping coefficient changing member according to a value of the input signal derived from an input signal sensor, e.g., the sprung mass vertical G sensor.

Abstract: In an apparatus for controlling a variable damping coefficient for at least one vehicular shock absorber, the shock absorber being interposed between a vehicle body and a tire wheel, an adjuster of the shock absorber which is so constructed as to change its position so as to provide an optimum damping coefficient for the shock absorber in response to a drive by means of an actuator (pulse motor), vehicle behavior detector which is so constructed as to detect a vehicle behavior, a damping coefficient control portion to derive an optimum damping coefficient according to the vehicular behavior, and a drive/control portion to form a drive/control signal to actuate the actuator, the drive/control portion is separated from the damping coefficient control portion and is integrally incorporated into the actuator.

Abstract: In a vehicular suspension a vertical acceleration of a sprung mass of a vehicular body and a relative speed between the sprung mass and an unsprung mass (viz., a wheel assembly) are detected. A sprung mass vibrating frequency is derived on the basis of detected vertical accelleration and relative speed, and a control unit determines whether the derived sprung mass vibrating frequency is equal to or higher than a predetermined dead frequency or not. The control unit outputs a control signal to the damper to change the damping force coefficient on the basis of the determination of whether the derived sprung mass vibrating frequency is equal to or higher than a predetermined dead frequency or not.

Abstract: The damping coefficient of a shock absorber of a suspension unit for a vehicle body of an automobile is varied in accordance with a vertical speed of the vehicle body such that it is normally varied in proportion to said vertical speed indicative signal however, from the time the vertical speed satisfies a predetermined relationship with a threshold level the largest damping coefficient is established and maintained and until the vertical speed reaches a peak.

Abstract: A vibration damper assembly comprises a torsional vibration damper with torsional springs, a mass body, and a resilient drive plate which serves as a bending stress damper. With a bearing on a reinforcement block connected to the crankshaft, the torsional vibration damper has an output member rotatably supported by the crankshaft. The resilient driver plate is operatively disposed in torque transmission relationship between the crankshaft and the mass body in such a manner as to coextend radially outwardly from the crankshaft with the torsional vibration damper.

Abstract: A flywheel includes an input member secured to a drive shaft, an output member rotatably supported on the input member, and a plurality of dash pots for connecting the input and output members to each other. The dash pots serve to transmit torque from the drive shaft to the output member and to damp torsional vibration transmitted from a drive shaft to the input member.

Abstract: A gear train of a rear wheel steering arrangement for an automotive vehicle includes a worm gear which is driven by a motor to steer rear wheels. The worm gear is designed to exhibit a reverse rotation efficiency more than zero so that when reverse torque is transmitted from a worm wheel to a worm, the worm is allowed to rotate in a reverse direction.

Abstract: A system and method for controlling a damper of vehicular suspension in which when the vehicle runs on a paved road and a frequency at which the detected sprung mass acceleration exceeds a dead zone is below a set value, the damping force characteristic is optimally controlled in a predetermined variable range. When the vehicle runs on a rough road and a frequency at which the detected acceleration exceeds the dead zone is above the set value, a minimum damping force limit of the predetermined variable range of the damping force characteristic is shifted toward a relatively high damping force side, The dead zone is set with an average value of the acceleration of sprung mass as a center. Hence, when the vehicle turns and zigzags, the vehicular body is inclined so that an absolute value of the sprung mass acceleration is largely changed. In this case, when an average value of the acceleration of the sprung mass is accordingly changed and the dead zone is accordingly shifted.

Abstract: A connecting arrangement for an automotive rear wheel steering unit is provided which is adapted for connecting an output shaft of a rear wheel steering gear train and a steering rod for steering rear wheels. The connecting arrangement includes a tapered portion formed on the output shaft, a tapered bore formed in the steering rod for receiving the tapered portion, and a fastener for locking the tapered portion of the output shaft to the tapered bore of the steering rod. With these arrangements, easy connecting operation is established with high mounting accuracy.

Abstract: A controller of each suspension unit is provided with a time difference setting block for deriving a time difference between a time at which front wheels have passed over a given portion of road surface and a time at which rear wheels have passed on the same portion of road surface, a correction block for deriving a correction value corresponding to a difference between a required optimum damping force on each of the front wheel suspension units and actually generated damping force on each of the front wheel suspension units, and a rear wheel suspension controlling block for deriving an optimum damping force on the basis of a presently input signal derived from a vehicular behavior detector installed on a rear wheel side and the correction value past by the time difference and outputting a change control signal to the damping force coefficient changing mechanism installed for the rear wheel suspension units.

Abstract: A brake-fluid reflux type anti-skid brake control system for automotive vehicles, comprises a main brake-fluid supply circuit, a brake-fluid reflux circuit refluxing the brake fluid from the wheel cylinder to the main brake-fluid supply circuit during operation of the anti-skid brake control system, and a brake-fluid flow control valve arranged in the supply circuit. The flow control valve employs a throttling device responsive to the pressure difference between the master-cylinder side and the fluid pressure of the wheel-cylinder side, such that when the pressure difference is less than a predetermined threshold the throttling device operates at a fully open mode, and when the pressure difference is greater than or equal to the threshold the throttling device operates at a fully throttling mode.