Abstract: 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.

Abstract: A steering system includes a clutch that is disposed in a steering force transmission path between a steering wheel and steered wheels and that mechanically disconnects the steering force transmission path when energized, and mechanically connects the path when de-energized, and a an upstream sensor and a downstream sensor each of which detects at least one of a steering torque and a steering angle in the steering force transmission path. At least one of the upstream sensor and the downstream sensor detects an energization status of the clutch. A detected value of at least one of the steering torque and the steering angle is corrected using a first correction value when the clutch is energized, and the detected value of at least one of the steering torque and the steering angle is corrected using a second correction value different from the first correction value when the clutch is de-energized.

Abstract: A vehicle steering system includes a clutch provided on a power transmission path extending from a steering wheel to steered wheels, a reactive-force motor connected to a first portion of the power transmission path, which is closer to the steering wheel than the clutch is, a steering motor including a first motor coil and a second motor coil, and connected to a second portion of the power transmission path, which is closer to the steered wheels than the clutch is, a driving circuit configured to supply electric power to the reactive-force motor, a first driving circuit configured to supply electric power to the first motor coil, and a second driving circuit configured to supply electric power to the second motor coil.

Abstract: 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.

Abstract: An ECU acquires a steering torque detected by a torque sensor (step S1). The ECU drives an electromagnet of a solenoid actuator (step S2). The ECU drives a steering operation motor in accordance with the direction of the detected steering torque acquired in step S1 to 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 S3). When a predetermined time has elapsed since driving of the steering operation motor in step S3 (step S4: YES), the ECU 40 reverses 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 S5).

Abstract: An ECU acquires a steering torque detected by a torque sensor (step S1). The ECU drives an electromagnet of a solenoid actuator (step S2). The ECU drives a steering operation motor in accordance with the direction of the detected steering torque acquired in step S1 to 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 S3). When a predetermined time has elapsed since driving of the steering operation motor in step S3 (step S4: YES), the ECU 40 reverses 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 S5).

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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 t1) 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.

Abstract: 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.

Abstract: 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.

Abstract: 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 t1) 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.

Abstract: 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.