Jtekt Corporation

Koyo Seiko Company, Ltd.

Masanori Arima

Shingo Maeda

Kosuke Yamanaka

Naoki Maeda

Atsushi Ishihara

Tatsuma Kouchi

Daisuke Maeda

Kunihiro Oka

Takehiro Saruwatari

Yasuhiko Hasuda

Takeshi Ueda

Ryouhei Hayama

Katsutoshi Nishizaki

Masaya Segawa

Shirou Nakano

Ken Matsubara

Hideki Higashira

Takanobu Takamatsu

Sadahiro Kawahara

Keita Nimura

A vehicular steering system includes a driving wheel, a wheel drive actuator that rotationally drives the driving wheel, a steering operation mechanism that steers the driving wheel, a steering operation actuator that applies a steering operation force that is used to steer the driving wheel to the steering operation mechanism, and a hydraulic circuit that transmits the rotational driving force of the wheel drive actuator to the steering operation mechanism via hydraulic oil as a steering operation force.

Vehicular steering system

A vehicle includes: a pair of front wheels; a pair of rear wheels; a front-wheel motor configured to drive the front wheels; a rear-wheel motor configured to drive the rear wheels; and a reducer configured to reduce a rotation speed of one of the front-wheel motor and the rear-wheel motor, and transmit drive power to the wheels driven by one of the motors. The one of the front-wheel motor and the rear-wheel motor is a motor with a rotation speed higher and torque lower than those of the other one of the motors.

Vehicle and vehicle driving device

A variable stiffness stabilizer device () has a stabilizer bar () and actuators (). The stabilizer bar () has a torsion bar () extending in the lateral direction (X) of a vehicle and arms () connected through bend portions () to the ends () of the torsion bar () and bendingly deformed according to the strokes of wheel supporting members (). Variable bending stiffness parts () of the arms () are rotatable about the axes (C) of the arms (), so that the bending stiffness of the arms () can be changed according to their rotational positions. The actuators () rotationally drive the variable bending stiffness parts () about the axes (C) to adjust the rotational positions of the variable bending stiffness parts ().

Variable stiffness stabilizer device

There is provided a vehicle steering system which includes an electric motor for imparting a steering force to a steering mechanism of a vehicle and an automatic parking controller for executing an automatic parking control by controlling the electric motor, wherein the automatic parking controller controls an energizing voltage of the electric motor by imparting a square wave to the electric motor and increasing/decreasing a neutral point voltage of a winding of the electric motor.

Vehicle steering system

In a steering-without-driving state, a larger current limit value, drive limit time and steering angle deviation threshold value are set than when a low-speed driving state occurs. An automatic parking mode is held until a time period over which a state where a motor current value of an electric motor which drives a steering mechanism is equal to the current limit value reaches the drive limit time. Even though the state where the motor current value is equal to the current limit value has continued over the drive limit time, the automatic parking mode is held during the steering angle deviation not exceeding the steering angle deviation threshold value. When the state where the motor current value is equal to the current limit value has continued over the drive limit time Ta and that the steering angle deviation exceeds the threshold value, the automatic parking control is cancelled.

A brake application speed is compared with a speed threshold value so as to judge whether or not a braking operation being performed is an emergency braking operation. If not the emergency braking operation, an automatic parking mode is held. When the emergency braking operation is in effect, control information related to a state of an automatic parking control then is stored in a control information storage section, and the automatic parking control is cancelled. Thereafter, when a steering operation or a gearshift operation is performed before a cancellation of application of the brake is detected, the process is ended, and the control mode is held in an assist mode. When the application of the brake is cancelled with neither the steering operation nor the gearshift operation performed, the control information is read in so as to resume the automatic parking control.

A vehicle steering system includes: a steering actuator that imparts a steering force to a steering mechanism of a vehicle; an automatic steering controller that performs an automatic steering control by controlling the steering actuator; a driving state detector that detects a driving state of the vehicle during the automatic steering control; a threshold value setting unit that variably sets a threshold value for permitting an intervention in the automatic steering control; and an automatic steering intervention unit that intervenes in the automatic steering control based on a threshold value set by the threshold value setting unit.

An automatic parking control is cancelled when a motor current has not yet reached a maximum current value Iwith a steering angle deviation exceeding a deviation threshold value. In addition, the automatic parking control is cancelled when a steering speed has not yet reached a maximum steering speed with a state where the motor current has reached and remains at the maximum steering speed continuing over a first time period. On the other hand, when a state where the steering speed has reached and remains at the maximum steering speed continues over a second time period, it is determined that there occurs an output shortage of a steering actuator, an automatic parking condition is recalculated, so as to allow the automatic parking continue to continue.

In an electric power steering system, a second bevel gear is allowed to move toward a first bevel gear and is biased by a biasing member toward the first bevel gear thereby to be moved toward the first bevel gear as following the wearing away of these bevel gears. In an electric power steering system, a support shaft formed with the first bevel gear at its distal end is rotatably supported by a retaining member, which is mounted to a support-shaft housing as allowed to move axially of the support shaft. The retaining member is adjusted for its position relative to the support-shaft housing with respect to the axial direction of the support shaft by means of a retaining member adjuster. The first bevel gear is moved toward the second bevel gear as following the wearing away of these bevel gears. In an electric power steering system, the support shaft formed with the first bevel gear at its distal end is allowed to move toward the second bevel gear and is biased by the biasing member toward the second bevel gear, so that the first bevel gear is moved toward the second bevel gear according to the wearing away of these bevel gears.

Electric power steering system

In a steering device, the rotation of the input shaft corresponding to the steering operation is transmitted to the output shaft via a rotation transmission mechanism, and is transmitted from the output shaft to the wheels of the vehicle by a steering gear so that the steering angle varies. A control device controls an electromotive actuator used to drive a constituent element of the rotation transmission mechanism in accordance with a variable quantity that expresses the traveling conditions of the vehicle, on the basis of the respective detection values of an input sensor used to detect the amount of input into the input shaft, an output sensor used to detect the amount of output of the output shaft and a traveling condition sensor used to detect the variable quantity that expresses the traveling conditions of the vehicle, so that the ratio of the transmission of rotation from the input shaft to the output shaft is altered in accordance with the variable quantity that expresses the traveling conditions.

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Nara, Japan

Masanori Arima