Jtekt Corporation

Panasonic Intellectual Property Management Co., Ltd.

Keisuke Izutani

Masahiko Sakamaki

Hiroshi Kawamura

Akihiko Shiina

Tomonari Yamakawa

Kazuyuki Yoshida

Tomoya Yamatani

Takayuki Sugawara

Kenji Harada

Ayumi Kondo

Keitaro Hoshiba

Tetsuya Ohashi

Yuta Hara

Takuya Miyazaki

Taichi Hanamori

Michio Yamamoto

Sho Yoshida

A vehicle steering device, in which a steering member and a steering operation mechanism are not mechanically coupled, includes a reaction force motor that applies a reaction force to the steering member, and a reaction force motor control unit that controls the reaction force motor. The reaction force motor control unit includes a target rotational angle setter that sets a target rotational angle for an output shaft at a position close to the side of the neutral position of the output shaft with respect to the rotational angle of the output shaft corresponding to a steered angle limit value by a rotational angle matching steering torque detected by a torque sensor when a steered angle has reached the steered angle limit value and the steering torque that is larger than the steering torque at the time when the steered angle limit value was reached is applied to a steering wheel.

Vehicle steering device

An ECU acquires a steering torque detected by a torque sensor (step S). The ECU drives an electromagnet of a solenoid actuator (step S). The ECU drives a steering operation motor in accordance with the direction of the detected steering torque acquired in step Sto apply, to an output shaft of a clutch, a torque acting in such a direction that a torque being exerted on a clutch mechanism is reduced (step S). When a predetermined time has elapsed since driving of the steering operation motor in step S(step S: YES), the ECUreverses a driving direction of the steering operation motor to apply, to the output shaft of the clutch, a torque acting in a direction opposite to the direction of the last torque applied (step S).

Vehicular steering system

A first valve opening degree correction value computation unit computes a correction value (first valve opening degree correction value) for the absolute value of a valve opening degree command value on the basis of a rotation speed deviation computed by a rotation speed deviation computation unit in a pump driving motor control unit. A second valve opening degree computation unit computes a correction value (second valve opening degree correction value) for the valve opening degree command value on the basis of the sign of the valve opening degree command value and the first valve opening degree correction value. A correction value addition unit adds the second valve opening degree correction value to the valve opening degree command value set by the valve opening degree command value setting unit.

Hydraulic power steering system

When an ECU is powered on, an overall control unit determines whether a temperature detected by a temperature sensor is lower than or equal to a predetermined temperature. When it is determined that the detected temperature is lower than or equal to the predetermined temperature, the overall control unit provides a second operation start command for operating a valve driving motor control unit in a rotation direction alternately switching mode, to the valve driving motor control unit. When the valve driving motor control unit receives the second operation start command from the overall control unit, the valve driving motor control unit starts operating in the rotation direction alternately switching mode.

A hydraulic power steering system includes a rotation angle sensor that detects a rotation angle of a shaft. A rotary valve includes a valve element that rotates together with the shaft of an electric motor and a housing that has an internal space connected to oil passages. A control unit reflects an output from the rotation angle sensor on control of the electric motor.

An electric power steering apparatus comprises a charge-discharge circuit capable of configuring a circuit for charging an auxiliary power supply and a circuit for discharging a battery and the auxiliary power supply as well as configuring a discharge-preference circuit which enables only the discharge of the auxiliary power supply while avoiding the charge thereof. In the apparatus, a control circuit performs a power latch operation of carrying on control till the end of a predetermined period of time following an operation of turning off an ignition key, and also causes the charge-discharge circuit to configure the discharge-preference circuit thereby enabling steering assist accompanied by the discharge of the auxiliary power supply.

Electric power steering apparatus and control method therefor

An electric power steering apparatus drives a motor to generate a steering assist force according to a steering torque and includes an output circuit for supplying the motor with electric power from at least one of a battery and an auxiliary power supply. The electric power steering apparatus has a control circuit which at or after detection of a breakdown of the battery, determines a length of time to the end of steering assist (decreasing time t) based on the amount of energy stored in the auxiliary power supplies and which takes the determined length of time to perform output decreasing control to gradually decrease the upper limit of power supplied for the steering assist to practically zero according to a constant gradient. Thus is provided an electric power steering apparatus which is adapted to prevent a sudden fall of the steering assist force in the event of a battery breakdown while effectively utilizing the available stored energy.

Electric power steering apparatus

An inverter energy consumption calculating portion estimates the actual power consumption of a steering operation assist motor after an engine is placed in an idle-stop state, and a command value of current to be supplied to the steering operation assist motor is limited such that the command value is smaller as the energy consumption is larger. The inverter energy consumption calculating portion calculates the energy consumption of an inverter drive circuit by integrating an amount of electric power consumed by the drive circuit.

Growing community of inventors

Yamatotakada, Japan

Keisuke Izutani