A turning device includes a turning shaft having a first ball screw groove as one of a left screw and a right screw and a second ball screw groove as the other of the left screw and the right screw and turning wheels to be turned by moving in an axial direction, a first electric motor generating a first driving force, a second electric motor operating independently of the first electric motor and generating a second driving force, a first ball screw nut transmitting the first driving force generated by the first electric motor to the first ball screw groove, a second ball screw nut transmitting the second driving force generated by the second electric motor to the second ball screw groove, and a rotation regulating part regulating relative rotation of the turning shaft around an axis with respect to a housing.

Provided is a rotary electric machine including a stator including a plurality of stator pieces, a rotor being arranged inside the stator and rotating about a rotation axis, a housing holding the stator and the rotor, a lid member preventing the stator and the rotor from coming out of the housing, and a cylindrical frame forming the stator by containing the plurality of stator pieces and being internally mounted in the housing, in which a first fixing portion and a second fixing portion for fixing the frame to the housing are disposed at both end portions of the frame along an extending direction of the rotation axis.

A steer-by-wire control system adapted for use with a material handling vehicle such as a forklift includes a controller programmed to receive input indicative of a desired direction of travel of the material handling vehicle and to control an actuator coupled with the steered wheels of the material handling vehicle to change the direction of travel of the vehicle.

According to the embodiments of the present invention, the overall size reduction allows installation space to be advantageously secured, reduction in noise generated during operation improves the comfort of the driver, and the strength and stability of the connective structure between parts can be increased and power transmission can be more effective.

An actuator for imparting steering movement to a tiller of a propulsion unit of a marine vessel comprises an absolute position sensor operable to sense a steering position and a relative position sensor operable to sense a position of the motor. A steering control unit calibrates the relative position sensor based on a signal of the absolute position sensor. Calibration of the relative position sensor based on a signal of the absolute position sensor initializes an accumulative position which accumulates a relative position as the actuator moves over time.

An apparatus for use in turning steerable vehicle wheels includes a steering column having a pinion connected with a vehicle steering wheel such that rotation of the steering wheel results in rotation of the pinion. An electrically powered steering unit includes an electric motor having a first output shaft rotatable about an axis. A first planetary gear stage has a first gear reduction ratio and is driven by the first output shaft. A second planetary gear stage is driven by the first planetary gear stage and the pinion and has a second gear reduction ratio different from the first gear reduction ratio. A second output shaft is driven by the second planetary gear stage and coupled to the steerable wheels such that rotation of the second output shaft affects steering of the vehicle wheels.

A steering device according to one aspect of the disclosure includes: a speed reducer configured to decelerate a rotational power input from one surface side while increasing a torque and output rotation from an output section disposed on the other surface side; a motor provided on the one surface side and configured to input the rotational power to the speed reducer; and a control device for controlling the motor. The motor includes a rotor for generating the rotational power. The rotor includes a rotor output shaft disposed coaxially with an output axis of the output section. The motor inputs the rotational power from one end side of the rotor output shaft to the speed reducer. The control device is disposed on the other end side of the rotor output shaft coaxially with the rotor output shaft and includes a sensing unit for sensing rotation of the rotor.

A steering device according to one aspect of the disclosure includes: a speed reducer configured to decelerate a rotational power input from one surface side while increasing a torque and output rotation from an output section disposed on the other surface side; a motor provided on the one surface side and configured to input the rotational power to the speed reducer; and a control device for controlling the motor. The motor includes a rotor for generating the rotational power. The rotor includes a rotor output shaft disposed coaxially with an output axis of the output section. The motor inputs the rotational power from one end side of the rotor output shaft to the speed reducer. The control device is disposed on the other end side of the rotor output shaft coaxially with the rotor output shaft and includes a sensing unit for sensing rotation of the rotor.

A steering axle for a steerable vehicle has an axle housing and a steering drive with an electric motor and motor shaft. A first planetary stage includes a first sun gear, first planet gears, and a first planet carrier. A last planetary stage includes a last sun gear, last planet gears, a last planet carrier, and a ring gear. A force flux from the motor shaft runs via the first sun gear and the first planet gears to the first planet carrier. The force flux furthermore runs via the last sun gear to the last planet gears. The force flux furthermore runs from the last planet gears to the ring gear. In relation to the axle housing, the ring gear is pivotably mounted about a pivot axis. The last planet carrier is connected in a rotationally fixed manner to the axle housing. Also disclosed is a corresponding industrial truck.

A steering drive includes an electric motor with a motor shaft and a steering lever rotatable about a pivot axis. A first planetary stage has a first sun gear, first planet gears, a first ring gear, and a first planet carrier. A final planetary stage has a final sun gear, final planet gears, a final ring gear, and a final planet carrier. A force flow runs from the motor shaft to the first sun gear, and from the first sun gear via the first planet gears to the first planet carrier and to the first ring gear. The force flow runs via the final sun gear and via the final planet gears to the final ring gear, runs from the first ring gear and from the final ring gear to the steering lever, and runs via a first sun gear shaft from the electric motor to the first sun gear.