A spindle nut (S) for a ball screw is conventionally designed as a hollow cylinder with a central-symmetrical middle longitudinal axis (Z). The spindle nut has an internal thread, which is designed as a ball groove (K) arranged on the cylinder inner surface. Pairs of load-relief bores (B) serve as substantially cylindrical channels for guiding the balls out of and into the ball channel (K) through the wall of the spindle nut. Each load-relief bore (B) is distinguished by a generatrix (L), which has an intersection point (C) with the thread base line of the ball channel (K) and constitutes the geometric continuation of the traveling path of a ball from the ball channel (K) into the load-relief bore (B). A tangent (T) to the cylinder surface (G) runs in a parallel manner at a spacing a >0 to the generatrix (L), both T and L being perpendicular to a common normal (R) to the middle longitudinal axis (Z).

An actuating mechanism includes a transmission element configured to be displaced parallel to a transmission direction, an actuating element configured to perform an actuating movement to cause the displacement of the transmission element in the transmission direction, a conversion mechanism arranged between the transmission element and the actuating element which converts the actuating movement of the actuating element into the displacement of the transmission element, and a bracing element configured to introduce a pretension, preferably an elastic pretension, at least into the conversion mechanism. The invention also relates to a clutch actuator and a transmission actuator having an actuating mechanism in accordance with the present invention.

A ball screw assembly for use in an actuator is provided. The ball to screw assembly may include a ball screw supported for rotation by the actuator. A ball nut may be provided around the ball screw and may be held against rotation with the ball screw by said actuator. A primary load path may be provided between the ball screw and the ball nut for operatively coupling the ball nut with the ball screw. A secondary load path may be provided between the ball screw and the ball nut, wherein the secondary load path can be disengaged during a normal operating mode of the ball screw assembly and the secondary load path can be engaged during a second operating mode of the ball screw assembly.

In a ball screw apparatus, a ball train including a plurality of main balls is housed in a raceway between a ball track of a ball nut and a ball track of a ball screw shaft. A coil spring housed in the raceway includes a first end that engages with an end of the ball train and a second end supported by a stopper (a first recessed portion, a protruding portion, or the like) of the ball nut. A stopper ball having a diameter larger than the diameter of the main ball is interposed between the stopper and the second end of the coil spring.

A linear motion system includes a guiding member, a moving member, a plurality of rolling members, a controller, a preload sensing member and a preload adjusting module. The moving member is slidably disposed on the guiding member, and the moving member and the guiding member together form a circulation path. The rolling members are accommodated in the circulation path. The preload sensing member is disposed on the moving member. The preload sensing member detects a preload value generated by the rolling members and applied to the moving member, and outputs a detecting signal to the controller. The preload driver and adjusting assembly of the preload adjusting module are disposed on the moving member. The controller controls the preload driver to adjust the adjusting assembly according to the detecting signal to adjust the preload value to a preset value.

Linear actuators are described herein. In particular embodiments, a linear actuator includes an everted ball screw assembly comprising a hollow screw shaft with internal threads, a ball cylinder concentrically positioned therein and having external threads, and a plurality of bearing balls sized to fit in a substantially contiguous series along a working pathway defined by the space between the internal and external threads. The linear actuator may include a support bearing for rotatably supporting the screw shaft in a housing. The ball cylinder in particular embodiments includes an internal return path along which the balls return to the working pathway. The everted ball screw assembly may include a lash reduction assembly and one or more scoop inserts that are sized and shaped to guide the balls into the internal return path and back onto the working pathway.

A steering column device includes a male screw shaft member supported by an outer column and a female screw member provided in a link member. The female screw member and the male screw shaft member are moved relative to each other by rotation of the male screw shaft member, causing the link member to swing relative to the outer column. The female screw member includes a main body section supported by the link member, a fragile section provided on one side of the main body section, and a screw engaging section provided on the opposite side of the fragile section from the main body section. In a state where an adjust nut is screwed to the screw engaging section, a distal end portion of the adjust nut comes into contact with the main body section and extends the fragile section in the axial direction of the male screw shaft member.

A linear motion system includes a guiding member, a moving member, a plurality of rolling members, a controller, a preload sensing member and a preload adjusting module. The moving member is slidably disposed on the guiding member, and the moving member and the guiding member together form a circulation path. The rolling members are accommodated in the circulation path. The preload sensing member is disposed on the moving member. The preload sensing member detects a preload value generated by the rolling members and applied to the moving member, and outputs a detecting signal to the controller. The preload driver and adjusting assembly of the preload adjusting module are disposed on the moving member. The controller controls the preload driver to adjust the adjusting assembly according to the detecting signal to adjust the preload value to a preset value.

A linear motion system comprises a guiding member, a moving member, a plurality of rolling members and a preload adjusting module. The moving member is slidably disposed on the guiding member. The moving member and the guiding member together form a circulation path. When the guiding member moves with relative to the moving member, the moving member can generate a linear movement with relative to the guiding member. The rolling members are accommodated in the circulation path. The preload adjusting module is disposed on the moving member, and comprises a preload assembly and a preload regulator. The preload regulator applies a thrust to the preload assembly to adjust a preload value generated by the rolling members and applied to the moving member.

A steering assembly includes a rack and an adjustment assembly. The rack has a first side surface, a second side surface disposed opposite the first side surface, a first surface extending between the first side surface and the second side surface, and a second surface disposed opposite the first surface. The adjustment assembly is arranged to apply orthogonal biasing forces to a pair of orthogonal surfaces of the non-cylindrical steering rack.