Abstract: A power steering system for a motor vehicle comprises a speed sensor 11, a steering torque sensor 12, a current calculating/driving circuit 21 for outputting a motor current command value on the basis of the vehicle speed and the steering torque, an assist torque generating electric motor 10 coupled to the steering system through an electromagnetic clutch 9, a clutch control circuit 50 for controlling a coupling effort of the electromagnetic clutch, an abnormal torque decision calculating circuit 31 for arithmetically determining an abnormal torque and a vehicle speed corresponding to the abnormal torque for a predetermined reference temporal duration to thereby output both an abnormal torque decision value indicating an abnormal torque corresponding to the vehicle speed detected by the vehicle speed sensor and the reference temporal duration, a load torque arithmetic circuit 33 for arithmetically determining both a load torque value indicating a sum of the steering torque detected by the steering torque sens

Abstract: A motor-driven power steering control system of a motor vehicle for assisting a driver in manipulating a steering wheel by making use of an assist torque generated by a reversible motor which is operatively coupled to a steering mechanism of the motor vehicle includes an electric reversible motor mechanically coupled to a steering system of the motor vehicle through an electromagnetic clutch, a motor drive circuit, an H-bridge switching driver circuit for driving the electric reversible motor in forward or reverse direction under the control of the motor drive circuit, and a clutch control circuit for controlling the electromagnetic clutch.

Abstract: A signal corresponding to steering torque detected by a torque detector is inputted into both a control device and a torque signal direction determining device 19. Only when the signal directions of both device are coincident, a signal to drive a motor in that direction is outputted from a motor drive circuit. In this case, even when the steering torque is in a dead zone, a signal of a predetermined direction can be outputted from the torque signal direction determining device by a switching signal. Accordingly, in the power steering control device, even when a torque direction signal sent from the direction determining device is in a dead zone, a signal for driving the motor to assist a steering shaft with rotation is made to be outputted in a predetermined direction, so that steering feelings can be improved when a steering wheel is suddenly reversed.

Abstract: A control apparatus for an electric motor-driven power steering system includes a main CPU for arithmetically determining the steering assist torque to be generated by the electric motor and a driving direction thereof on the basis of outputs of a torque sensor and the vehicle speed sensor, a subsidiary CPU for arithmetically determining the driving direction of the motor on the basis of outputs of the torque sensor and the vehicle speed sensor and compare the driving direction signal supplied from the main CPU with a signal of the driving direction determined by the subsidiary CPU to generate a second driving direction signal. A coincidence/discrepancy signal representing coincidence or discrepancy between the motor driving direction signal and the steering torque signal is also supplied to the subsidiary CPU from the main CPU.

Abstract: A motor for a motor-assisted power steering device is controlled with a control value which is obtained by detecting an error between an actual steering torque which has undergone phase lead compensation and a target steering torque, and by summing a proportional value, an integration value and a differentiation value of the error, or with a control value which is obtained by detecting an error between actual steering torque and a target torque; obtaining a proportional value, an integration value and a differentiation value of the error; clipping the lower limit value of the integration value with a first clipping circuit, and clipping the upper and lower limit values of motor-controlling quantity obtained by summing the proportional value, the integration value and the differentiation value by using a second clipping circuit.

Abstract: An electric power steering control device includes a motor controller for controlling an electric motor providing the assisting steering torque; and a clutch controller for controlling an electromagnetic clutch selectively connecting the assisting steering torque of the motor to the steering system. The degree of engagement (connection) of the clutch corresponds to the clutch current command level I.sub.C. When the vehicle speed is above a predetermined speed V.sub.0 (i.e., during high speed driving), the clutch current I.sub.C is set at a predetermined half current level I.sub.CR. During low vehicle speeds below V.sub.0, the clutch current I.sub.C is gradually decreased to the half current level I.sub.CR as the vehicle speed increases to V.sub.0. When the steering torque T is above a first predetermined level T1 indicative of an abnormality during high speed operation, the clutch current I.sub.C is set at a minimal level I.sub.CO. The steering torque T is returned to the half current level I.sub.

Abstract: A motor-driven type power steering apparatus for assisting a driver in manipulating a steering wheel of a motor vehicle includes a steering-wheel return state decision circuit for deciding whether the steering wheel is in the state to be returned to a center position, a control quantity generating and selecting circuit for generating control quantities corresponding to respective driving modes on the basis of a control quantity of the electric motor and selecting one of the control quantities in dependence on the result of the decision made as to the return state of the steering wheel, and a conversion circuit for converting the control quantities into PWM duty ratios, respectively. In the normal steering operation, switching elements for energizing the motor are driven with the PWM duty ratio corresponding to a first driving mode, while upon return of the steering wheel to the center position, the switching elements are driven with the PWM duty ratio corresponding to a second driving mode.

Abstract: A suspension control system having a suspension unit between a wheel and a body of a vehicle, a fluid supply device for supplying a fluid to the suspension unit, a fluid discharge device for discharging the fluid from the suspension unit, an amplitude measurement device for measuring the amplitude of vertical vibrations of the vehicle body, a threshold value setting device for setting a threshold value of the amplitude of vertical vibrations, a controller for cancelling expansion and contraction of the suspension unit by controlling the fluid supply and the fluid devices when the amplitude of vertical vibrations is equal to or larger than the threshold value, a counter for counting the number of times the fluid supply and fluid discharge devices are controlled by the controller in a predetermined time period, and a threshold value changing device for setting, when the number of times counted by the counter is equal to or larger than a reference number, the threshold value in the threshold value setting device

Abstract: A motor-driven power steering apparatus and method for a vehicle are able to avoid frequent on-off operations of an electromagnetic clutch 14 as much as possible, which connects or disconnects a motor 13 with or from a steering system, thus improving the durability of the clutch 14 and suppressing the generation of undesirable noise and shocks upon connection and disconnection of the clutch 14. A clutch controller 191 controls a clutch current Ic supplied to the clutch 14 based on the vehicle speed V in such a manner that it sets the clutch current Ic to a first predetermined clutch current level I(V) so as to place the clutch into a substantially engaged state when the vehicle speed V is less than a first predetermined vehicle speed Vo, and to a second predetermined clutch current level Icr which is less than the first predetermined clutch current level I(V) so as to place the clutch into a partially engaged state when the vehicle speed V is equal to or greater than the first predetermined vehicle speed Vo.

Abstract: A unified control device for a vehicle including an anti-skid braking system and power steering control system is controlled by two microcomputers (4B and 24B). On the basis of the outputs of the torque sensors (1a and 1b, etc.), the first microcomputer (4B) determines the driving direction and torque of the DC motor (9) providing the assisting steering torque for the steering wheel, and outputs the torque signal (T) and the first direction signal (D1) for the DC motor (9). The second microcomputer (24B) generates the brake operation signal (B) on the basis of the outputs of the road wheel velocity sensors (21a through 21d) and the brake switch (22). Further, on the basis of the output of the torque sensors (1a and 1b), the microcomputer (24B) determines the direction of the DC motor (9), and outputs the second direction signal (D2).

Abstract: A motor-driven power steering apparatus and method for a vehicle are able to avoid frequent on-off operations of an electromagnetic clutch 14 as much as possible, which connects or disconnects a motor 13 with or from a steering system, thus improving the durability of the clutch 14 and suppressing the generation of undesirable noise and shocks upon connection and disconnection of the clutch 14. The motor 13 is deenergized by a motor controller 191 when the vehicle speed V is equal to or greater than a predetermined value Vo. The clutch 14 is turned off to disconnect the motor from the steering system when an abnormality in the steering system is determined during high speed travel of the vehicle.

Abstract: An improved support apparatus such as a suspension apparatus for a vehicle is disclosed which has excellent response characteristics, can save power consumption and has excellent vibration-isolating capacity for isolating the transmission of high-frequency vibrations from a support member such as a road wheel to an object such as the body of a vehicle. To these end, in one embodiment, a linear motor is disposed between the object and the support member for telescopically supporting the object under magnetic effects. A position sensor senses the position of the object relative to a reference position. A low-pass filter filters high-frequency components of the output signal of the position sensor above a prescribed upper frequency limit. Based on the output signals of the position sensor and the low-pass filter, the current supply to the linear motor is controlled in such a manner as to offset a change in the output signal of the low-pass filter.

Abstract: The meshing between a rack which moves according to steering operation and a sector gear meshed with the rack is adjusted by the movement of an output shaft in its own axis direction which is united with the sector gear. A through hole is formed along the axis center line of the output shaft, and a threaded shaft is inserted into the through hole. The threaded shaft is screwed into the output shaft. One end of the threaded shaft is accessible for rotating from the side where a steering mechanism member is mounted. The other end of the threaded shaft is connected to a housing in a manner that the threaded shaft is rotatable around in its own axis but that the threaded shaft is unmovable in its own axis direction.

Abstract: A suspension control system for enhancing the response characteristic of a vehicle body vibration suppressing control by lowering the spring constant or the damping force to a first desired level for both front and rear wheels at a time or only the rear wheel for a predetermined time in accordance with a differential value of an output signal from an acceleration detecting means in the vertical direction of the vehicle body, to thereby soften the shock of the vehicle body when the rear wheels get over a protuberance, and also by changing the spring constant or the damping force settled beforehand to a second desired level for both front and rear wheels at a time in case an unnecessary vibration of the vehicle body is detected afterwards. The second desired level is held for a predetermined time or continuously to suppress vertical vibrations of the vehicle body.

Abstract: A control apparatus which detects vertical and/or lateral acceleration of a vehicle body so as to control characteristic of a support unit for supporting the vehicle body, in other words, a damping force and/or a spring constant of a suspension, or torsion quantity of a stabilizer, on the basis of quantity of acceleration or a differentiated value thereof and vibration cycle period of the acceleration.

Abstract: An ultrasonic wave type obstacle sensor which comprises a first ultrasonic microphone for transmitting intermittently ultrasonic waves to a road surface obliquely and forwardly at predetermined timing, a second ultrasonic microphone for receiving the ultrasonic waves reflected from the road surface side, a comparator for providing an obstacle detecting signal when a signal from the second ultrasonic microphone exceeds a predetermined level of judgement, and an obstacle discriminating device for generating an obstacle discriminating signal when the pulse width of the obstacle discriminating signal is a predetermined width or larger.

Abstract: A control apparatus for support unit of vehicle, wherein a physical quantity which affects characteristics of a support unit for supporting a vehicle body such as a suspension or stabilizer and a state quantity which shows movement of the body or support unit are detected. The similarity corresponding to the detected physical quantity and state quantity is calculated using fuzzy logic, request indexes of comfort to ride and operation stability are calculated from the similarity. The request indexes are composed to obtain the center of gravity, so as to judge the most optimum characteristics of the support unit. This control apparatus automatically substantially analoguely judges whether either of the comfort to ride or the operation stability should be prioritized.

Abstract: In the suspension controller of the present invention, there is provided a suspension or stabilizer characteristic change-over determining device whereby a damping force or a spring constant of a suspension or a torsional force of a stabilizer is calculated from a degree of similarity corresponding to a physical amount which exerts influence on the suspension or stabilizer characteristics and a state amount, using fuzzy logic, and when it is enhanced, this enhanced state of the suspension or the stabilizer is maintained for a set time. If during this period a set value of the damping force or the spring constant or the torsional force corresponding to the output which is responsive to the degree of similarity indicates a rather low state for a predetermined time or longer, the value of the damping force or the spring constant or the torsional force is set low and this state is maintained for a set time.

Abstract: A control apparatus which detects vertical and/or lateral vibrations of a vehicle body and controls, on the basis of amplitude and frequency of vibration, a characteristic of a support unit for supporting the vehicle body, such as, a damping force and a spring force of suspension or torsion quantity of a stabilizer. The control apparatus, when the detected vibration is high frequency vibration, obtains the frequency of vibration by a measured value of one cycle period, and, when the detected vibration is low frequency vibration, obtains the frequency of vibration by a measured value of a half cycle period.

Abstract: An acceleration sensor is disclosed which includes a weight, piezoelectric element(s), a charge amplifier, an insulation plate and a conductive casing. The insulation plate fixedly mounts the weight and piezoelectric element(s) and is fixed to the conductive casing which is maintained at the earth potential. Input terminals of the charge amplifier are connected to the output electrodes of the element(s) and a grounding circuit of the amplifier is connected to the conductive casing so that the input terminals of the amplifier are floated from the earth potential.