A ball screw in a steering system has a groove between the inner peripheral surface of a cylindrical ball nut through which a steered shaft extends and the outer peripheral surface of the steered shaft, and balls are accommodated in the groove. The balls rolling and flowing in the groove are returned from downstream to upstream via deflectors and a return passage member disposed in the ball nut. The return passage member has a first connection portion curved to connect one end of a linear portion of the return passage member to the first deflector, and a second connection portion curved to connect the other end of the linear portion to the second deflector. Each connection portion has an opening that opens in the return passage member longitudinal end face and an opening that opens in the return passage member outer periphery of toward the centerline of the ball nut.

A ball relief feature for a ball screw allows multiple turn ball circuits with reduced ball bearing stack-up within the ball screw assembly. Reliving bearing stack up allows for ball circuits having more turns without reducing the number of load carrying ball bearings of a typical ball nut. The ball relief feature reduces ball bearing stack-up by allowing the balls to re-distribute relative to one another and space themselves evenly in oversized portions of the ball circuit track other than the ball return mechanism.

An open nut and a ball screw assembly having the open nut are provided. The ball screw assembly includes a guider, an open nut, and a ball circulating assembly. The open nut includes an axial cylinder, an open shield, and two circulators. The two circulators are respectively disposed on a first axial wall and a second axial wall of the axial cylinder with an axial opening. Each of the circulators includes an inner member and an outer member. The inner member and the outer member are assembled to each other and are respectively in communication with an inner ball race between the guider and the open nut and an outer ball race of the open nut. Therefore, the inner ball race, ball races of the two circulators, and the outer ball race form a ball circulating race, and the ball circulating assembly rolls in the ball circulating race.

A multiliner for a ball nut, a ball nut and a ball screw assembly are provided. Methods of forming the multiliner are also provided. The multiliner includes return channels that are configured to prevent bearing balls from falling out of a retaining region in a radial direction. This allows bearing balls to travel past intermediate grooves formed in a cooperating threaded ball screw shaft.

A ball screw device having a screw shaft rotating during use, a nut moving linearly during use, balls, a fitting cylinder fixed to the nut, a housing, and an anti-rotation member, a first member, which is one of the nut and the fitting cylinder, having a retaining concave portion engaging with a radially inner portion of the anti-rotation member and including a closed surface, an insertion hole of the housing having a guide concave groove engaging with a radially outer portion of the anti-rotation member, the radially inner portion held between the closed surface and an axially end surface a second member, which is the other of the nut and the fitting cylinder, the radially outer portion being able to slide in the guide concave groove.

A ball screw device having a screw shaft rotating during use, a nut moving linearly during use, balls, a fitting cylinder fixed to the nut, a housing, and an anti-rotation member, a first member, which is one of the nut and the fitting cylinder, having a retaining concave portion engaging with a radially inner portion of the anti-rotation member and including a closed surface, an insertion hole of the housing having a guide concave groove engaging with a radially outer portion of the anti-rotation member, the radially inner portion held between the closed surface and an axially end surface a second member, which is the other of the nut and the fitting cylinder, the radially outer portion being able to slide in the guide concave groove.

To provide a nut that can suppress increase in the number of components. The nut according to the present disclosure includes a nut main body and a circulation component. The nut main body includes a housing part having a bow shape when viewed from an axial direction, a seat surface, a through hole, and a pair of side surfaces. The circulation component includes a circulation component main body, two arm parts extending toward both sides in a seat surface direction from the circulation component main body, ribs projecting from the respective two arm parts, and caulking parts obtained by caulking the ribs. Recessed parts that the caulking parts enter are disposed on the pair of side surfaces. A ball passage is disposed in the circulation component main body.

The present disclosure relates to a brake actuator unit and to an electromechanical brake. The brake actuator unit has a spindle, which is driven in rotation by an electric motor, and a brake piston in the form of a spindle nut, which surrounds the spindle and is configured to press against a brake lining.

The invention relates to a multiaxial machining center (30) for machining a part (35), comprising: a support plate for supporting a part (35) to be machined, a positioning carriage (36) that can be moved with respect to the support plate along at least one first axis of movement, a machining carriage (32) that can be moved with respect to the positioning carriage (36) along a second axis of movement perpendicular to said at least one first axis of movement, a connection mechanism between the machining carriage and the positioning carriage, which connection mechanism is configured to guide and move in translation the machining carriage, the connection mechanism furthermore comprising: a system for applying a predetermined force to the machining carriage (32) along the second axis of movement, a unit for controlling the force applied to the machining carriage (32) by the application system.

A piece type ball screw in a screw shaft with a spiral external thread groove on an outer peripheral surface, a nut which is fitted onto the screw shaft and has a spiral internal thread groove on an inner peripheral surface, a plurality of balls rotatably arranged in a track path formed between the external thread groove and the internal thread groove, and a piece member which is attached to the nut and connects the internal thread grooves to each other. The piece member includes a piece body in which a return groove connecting the internal thread grooves is formed and a pair of engaging portions which are provided on the piece body, extend in opposite directions in a circumferential direction of the nut, and engage with the internal thread groove of the nut. A joint portion between the piece body and the engaging portion has a fillet shape.