A steering system includes a two-way clutch, a worm wheel that is rotatable together with an input shaft, and a coil that generates a drive force for the two-way clutch to couple/decouple the input shaft and an output shaft to/from each other. The worm wheel has a center circular plate portion fixed to the input shaft, a radial ring portion that projects forward from a peripheral edge of the center circular plate portion, and a toothed portion that projects outward in the radial direction from the radial ring portion. The two-way clutch is disposed in a space surrounded by the center circular plate portion and the radial ring portion and formed on the front side with respect to the center circular plate portion. The coil surrounds an outer peripheral surface of the radial ring portion.

[Problem]

An object of the present invention is to provide an electric power steering apparatus that can perform an angle estimating by using a motor regenerative current so as to accurately perform an angle estimating even in a low speed steering.

[Means for Solving the Problem]

The present invention is the electric power steering apparatus that calculates a current command value based on at least a steering torque, driving-controls a motor, which applies an assist torque to a steering system based on the current command value, by an inverter with respective phase duties of a PWM, and detects an angle of the steering system or the motor, comprising: an angle estimating section to estimate the angle when a detecting system of the angle is failed, wherein the electric power steering apparatus performs an assist-control based on an estimating angle that is estimated at the angle estimating section. The present invention can be also adapted to the control of the motor having multi-system windings.

An electromechanical motor vehicle power steering mechanism may include an electric motor and a control unit. The electric motor may be configured to provide a steering assist force. The control unit may be configured to control a current to the electric motor. Further, the control unit may include two redundant power supply units. Each of the two redundant power supply units may be connected to a vehicle battery. Also, the two power supply units may each comprise a primary winding and a secondary winding as part of a flyback transformer with a shared iron core. The shared magnetic core may be E-shaped with a middle leg and two side legs. The primary winding and the secondary winding of one of the two redundant power supply units may be wound around a first of the two side legs.

A steering system includes: a steering shaft to which a steering member is coupled; a worm wheel attached to the steering shaft so as to be rotatable integrally with the steering shaft; a housing that houses the worm wheel; an output shaft that is coaxial with the steering shaft and rotatable relative to the steering shaft and coupled to a steering operation mechanism; and a clutch mechanism that enables and disables transmission of power between the steering shaft and the output shaft. The clutch mechanism is housed and disposed in an internal space in the housing.

An independent steering mechanism of controllable hydraulic locking type for left and right wheels is provided. The independent steering mechanism includes a power steering mechanism, a steering drive mechanism, a hydraulic locking mechanism and an electronic control unit. Power of the left and right steering motors flows through the worm, the worm gear, the gear to drive left and right racks to translate. Outer ends of the left and right racks are connected to left and right tie rods via spherical hinges respectively. Inner ends of the left and right racks are connected to a piston rod and a cylinder barrel via spherical hinges respectively. A left chamber and a right chamber in the hydraulic cylinder are connected to an oil reservoir via an electro-hydraulic valve. The left and right steering motor controllers for the left and right steering motor and the electro-hydraulic valve controller are communicated via CAN bus.

A steering apparatus for a steer by wire system includes a first motor and a second motor configured to provide a torque. A first planetary gear set is configured to receive the torque from the first motor and to generate a reaction torque required for steering. A second planetary gear set is configured to receive the torque from the steering wheel and the second motor, and to variably output a gear ratio for an input by the steering wheel depending on a rotation of the second motor. A stopping mechanism is configured to limit a maximum rotation angle of the steering wheel.

Provided is a steering controller configured to suppress deterioration of the operability of a steering wheel for steering steered wheels even when a driving voltage for a steering system has been decreased. When a clutch is in a disengaged state and steered wheels are steered by a steered-operation actuator while a reaction force is applied to steering wheel by a reaction-force actuator, if a driving voltage for the steered-operation actuator is decreased, a CPU opens relays and stops generation of torque by the steered-operation actuator. Meanwhile, a CPU engages the clutch and steers the steered wheels through cooperation between a steering torque input into the steering wheel and an assist torque generated by a reaction-force motor.

Provided is a steering controller configured to switch from an interruption state to a transmission state. In a state where power transmission from the steering wheel to steered wheels is interrupted, a maximum value selection processing circuit outputs a maximum value, out of a steered angle and a steering angle, to a limiting reaction force setting processing circuit. When the absolute value of the maximum value has become equal to or larger than a limitation start threshold value, the limiting reaction force setting processing circuit rapidly increases a limiting reaction force. An operation signal generation processing circuit controls a reaction-force motor to achieve a reaction force command value corresponding to the limiting reaction force. When the absolute value of the maximum value has become equal to or larger than an engagement threshold value, a clutch is engaged to transmit reaction force from the steered wheel-side to the steering wheel.

An active suspension system comprises at least one biasing device configured to support a body from a structure, and at least one motor. A magnetorheological (MR) fluid clutch apparatus(es) is coupled to the at least one motor to receive torque from the motor, the MR fluid clutch apparatus controllable to transmit a variable amount of torque. A mechanism is between the at least one MR fluid clutch apparatus and the body to convert the torque received from the at least one MR fluid clutch apparatus into a force on the body. Sensor(s) provide information indicative of a state of the body or structure. A controller receives the information indicative of the state of the body or structure and for outputting a signal to control the at least one MR fluid clutch apparatus in exerting a desired force on the body to control movement of the body according to a desired movement behavior.

An independent steering mechanism of controllable hydraulic locking type for left and right wheels is provided. The independent steering mechanism includes a power steering mechanism, a steering drive mechanism, a hydraulic locking mechanism and an electronic control unit. Power of the left and right steering motors flows through the worm, the worm gear, the gear to drive left and right racks to translate. Outer ends of the left and right racks are connected to left and right tie rods via spherical hinges respectively. Inner ends of the left and right racks are connected to a piston rod and a cylinder barrel via spherical hinges respectively. A left chamber and a right chamber in the hydraulic cylinder are connected to an oil reservoir via an electro-hydraulic valve. The left and right steering motor controllers for the left and right steering motor and the electro-hydraulic valve controller are communicated via CAN bus.