A steering system includes a housing, a steering operation shaft that is housed in the housing and configured to move in an axial direction to steer right and left steered wheels, a first drive source that generates a first drive force, a second drive source that generates a second drive force, a first power transfer unit that applies an axial force to the steering operation shaft with the first drive source, a second power transfer unit that applies an axial force to the steering operation shaft with the second drive force, a position detection sensor that is provided in the housing and detects an axial position of the steering operation shaft, and a control device that controls the first drive source and the second drive source using a detection result of the position detection sensor.

Methods and apparatus to determine rack force are disclosed. An example apparatus includes a rack to couple to a steering knuckle of a vehicle, a ball nut engaged with the rack, a first ring gear coupled to the ball nut, a first pinion fixed to a motor, the first pinion engaged with the first ring gear, the motor to rotate the ball nut to move the rack, a motor encoder to detect a rotation of the first pinion, a second ring gear coupled to the ball nut, and a sensor fixed to a second pinion, the second pinion engaged with the second ring gear, the second pinion to rotate as the second ring gear rotates, the sensor to detect a rotation of the second pinion, the rotation of the second pinion and the rotation of the first pinion corresponding to a force on the rack.

A steering system has a steering rod longitudinally displaceable in a housing and a steering motor acting on the steering rod via a ball screw drive. The steering rod has a recirculating ball thread interacting via spherical transmission elements with a transmission nut driven by the steering motor and that is rotatably mounted by a bearing arrangement with a pivot bearing having an inner ring to which a mechanism wheel is fixedly attached. The transmission nut is pivotably mounted on the mechanism wheel about a pivot axis oriented perpendicularly to the longitudinal axis of the steering rod, and has a curved joint section which interacts with a curved joint section of the mechanism wheel to form a pivoting bearing. An elastically deformed spring ring arranged between the joint sections provides freedom from play of the pivoting joint.

Methods, apparatus, systems and articles of manufacture for a steering apparatus for use with vehicles are disclosed. An example apparatus includes a housing for a vehicle steering system, a motor, an actuator, and a rack disposed in the housing, the motor to provide a torque to the actuator via a belt to translate the rack relative to the housing, and a first gear disposed between the motor and the actuator, the first gear to transfer the torque from the motor to the actuator when the belt does not provide the torque.

A steering system includes a mounting bracket, a drag link elongated from a first end rotatably coupled to the mounting bracket to a second end, a steering arm rotatably coupled to the second end, and a telescoping shaft rotatably coupled to the drag link. The drag link includes a housing and a rack slidable in the housing. The telescoping shaft is operably coupled to the drag link to slide the rack relative to the housing when the telescoping shaft rotates.

A rack-assist-type electric power steering apparatus may include: a motor pulley provided on or coupled to a shaft of a motor; a nut pulley provided on or coupled to an outer circumferential surface of a ball nut coupled to a rack bar via a ball; a belt coupled to the motor pulley and the nut pulley, the belt comprising provided with one or more first magnetic bodies; and a rack housing enclosing or housing at least a portion of the motor pulley, the nut pulley and the belt are housed. The rack housing may comprise one or more second magnetic bodies provided on an inner circumferential surface thereof facing or opposite to the belt. Alternatively, the rack housing may comprise a support portion protruding from an inner surface of the rack housing, and one or more second magnetic bodies may be provided on a surface of the support portion.

A ball screw device includes a screw shaft having a first screw groove formed on an outer circumference thereof, a ball screw nut having a second screw groove formed on an inner circumference thereof, and a plurality of balls disposed in a spiral ball raceway wherein the first screw groove and the second screw groove face each other. A circulation member is attached to an attachment hole radially penetrating the ball screw nut and a circulation path is formed, the circulation path allowing endless circulation of each of the balls rolling in the ball raceway by short-circuiting between two points of the ball raceway.

A power assisted steering system provides a gear reduction between a steering wheel and a steering mechanism and a much larger gear reduction between an electric motor and a steering mechanism. The system is back-driveable from the steering mechanism. The system utilizes a ball-screw, several helical gears, and two bevel gears. A rack fixed to the ball-screw nut drives a sector gear.

In a power steering device equipped with a rack shaft constructed by joining a first member having rack teeth and a second member serving as a ball screw shaft on which a ball screw groove is formed, a grinding process of the ball screw groove is performed on the second member by causing a grindstone to rotate and move along a rotation axis of the second member, while causing the second member to rotate about an axis of the second member as the rotation axis. The grinding process is performed so as to satisfy a specified machining condition g/(5p)<w<g/p, where w is a rotational speed of the second member during grinding of the ball screw groove, g is a rotational speed of the grindstone during grinding of the ball screw groove, and p is a circumferential length of one circumference of the ball screw groove around the rotation axis.

Electric power assisted steering (EPAS) systems for solid axle front suspension vehicles are described. An example EPAS system includes an idler arm having a first end and a second end. The first end of the idler arm is coupled to a frame of the vehicle. The example EPAS system further includes an EPAS rack assembly having an input shaft, a rack, an electric motor, and an output link. The rack is coupled to the input shaft and is movable in response to movement of the input shaft. The electric motor is coupled to the rack. The electric motor provides powered assistance to movement of the rack. The output link has a first end and a second end. The first end of the output link is coupled to the rack. The second end of the output link is coupled to the second end of the idler arm.