A power actuator assembly for a steering column assembly is provided. The power actuator assembly include an electric motor. Also included is a leadscrew. Further included is a gear arrangement operatively coupled to the electric motor, the gear arrangement driving rotation of the leadscrew. Yet further included is a nut threaded to the leadscrew, rotation of the leadscrew actuating linear motion of the nut relative to the leadscrew, the nut operatively coupled to a moveable portion of the steering column assembly to actuate motion of the moveable portion. Also included is a leadscrew housing, the leadscrew extending axially through the leadscrew housing. Further included is a helical bushing disposed between a radially inner surface of the leadscrew housing and a radially outer surface of the leadscrew.

A lead screw structure comprises a screw shaft having a thread on an outer circumferential surface thereof, a nut unit coupled to the screw shaft such that and a thread formed on an inner circumferential surface of the nut unit is engaged with the thread of the screw shaft, and a first elastic member disposed on a portion of the nut portion, in a direction of the screw shaft, to provide an elastic force to the nut portion in the screw shaft, thereby compensating for a gap between the thread of the outer circumferential surface of the screw shaft and the thread of the inner circumferential surface of the nut unit.

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.

A steering system includes a tie rod and an actuator assembly. The tie rod is movably disposed within a tie rod housing. The actuator assembly includes a first member and a second member. The first member extends from an actuator. The second member has a second member first end operatively connected to the first member and a second member second end operatively connected to the tie rod. The second member first end is arranged to translate the tie rod along a first axis responsive to the actuator moving the second member first end relative to a second axis.

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.

An electric power steering system includes: a steered shaft, a housing containing the steered shaft therein in a movable manner; a ball screw nut engaged threadedly to the steered shaft via a plurality of balls and configured to move the steered shaft in an axial direction; a double row angular contact ball bearing configured to retain the ball screw nut and to support the retained ball screw nut rotatably relative to the housing; a wall portion placed at either side of the double row angular contact ball bearing in the axial direction of the steered shaft, the wall portion being formed integrally with the housing; and an elastic member provided between the wall portion and the outer ring portion and configured to retain the double row angular contact ball bearing to be elastically displaceable in the axial direction.

The present embodiments relates to a reducer of an electric power steering device. An embodiment of the present embodiments provides a reducer of an electric power steering device, including: a worm shaft having a first worm shaft bearing and a second worm shaft bearing coupled to one end portion, which is connected to a motor shaft, and to the other end portion, which is opposite thereto, respectively; a gear housing that contains the first worm shaft bearing, the second worm shaft bearing, and the worm shaft; and a support member coupled to the inner peripheral surface of the hear housing so as to support the outer race of the second worm shaft toward the worm wheel and filled with a viscoelastic fluid.

An actuator of a steering system having a housing (2), a spindle drive arranged in the housing (2) which includes an axially movable spindle (5) that engages with a spindle nut (6) mounted in a fixed position. The spindle has at least one fastening end (8, 9), and at least one bearing journal (10, 11) arranged and able to move in the housing (2). The journal is connected to the at least one fastening end (8, 9) of the spindle (5), with at least one joint connection component (3, 4) which is arranged outside the housing (2) and is connected to the at least one bearing journal (10, 11). The at least one bearing journal (10, 11, 110) has a constriction (10v, 11v) that forms a flexible zone (122).

Actuator having a spindle drive (1) for a rear wheel steering system, including a spindle (2) with a spindle thread (2a) and a spindle nut (3) with a nut thread (3a). The spindle thread (2a) and the nut thread (3a) are designed as displacement threads and the spindle nut (3) threadedly engages with the axially displaceable spindle (2) by way of the displacement thread. The spindle thread (2a) and the nut thread (3a) are braced against one another, in the longitudinal direction of the spindle (2), by a bracing element (4). The bracing element (4) is in the form of a threaded ring having an internal thread (4a) which engages with the spindle thread (2a). The threaded ring (4) is supported relative to the spindle nut (3) by at least one spring element (5, 6), and the at least one spring element (5, 6) is made of an elastomer.

A bearing arrangement for supporting an endless screw of a steering gear on a gear housing of the steering gear. The bearing arrangement including a radial bearing rotationally connected to the endless screw. A resilient retention element connecting the radial bearing to the gear housing. The retention element is connected at the radial bearing side to an outer face of an outer bearing ring and fixed to the outer face of the outer bearing ring in an axially non-movable manner with respect to a longitudinal center axis of the radial bearing.