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.

A linear actuator assembling method includes a semi-finished product assembling step and a threaded shaft assembling step. The semi-finished product assembling step is to form a semi-finished product, and the semi-finished product includes a case, a main gear, and a main gear bearing. The main gear and the main gear bearing are surrounded and restricted by the case, and the main gear bearing is sleeved on the main gear. In the threaded shaft assembling step, a threaded shaft is reversely assembled, and one end of the threaded shaft is inserted into the main gear to allow the end of the threaded shaft to be restricted by the main gear.

A spindle drive comprising a threaded spindle with an external thread, a spindle nut with an internal thread that is in engagement with the external thread of the threaded spindle, characterized in that the external thread of the threaded spindle has multiple threaded areas that are separated from each other by first flattenings on their circumference extending in the longitudinal direction, and the first flattenings have guide areas that abut the core diameter of the internal thread of the spindle nut.

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).

A mechanical actuator for vehicles includes a ball nut having a hardened inner part defining a ball track, a malleable outer part comprising a riveting area with a riveting edge, and a bearing riveted with the riveting edge to the riveting area of the outer part of the ball nut.

A method for producing a ball raceway on a workpiece includes providing the workpiece, machining a preliminary thread profile on the workpiece and providing a thread rolling tool. The thread rolling tool has a tool shank, and the tool shank has a free end with a tool head having a roller profile. The method also includes clamping the workpiece into the thread rolling tool, rotating the workpiece about an axis of rotation, moving the tool shank longitudinally along the workpiece, and rolling the roller profile on the preliminary thread profile to generate a final thread profile.

A method for manufacturing a linear motion shaft includes: manufacturing a first shaft portion, and connecting the first shaft portion and a second shaft portion by friction welding. A first input section is formed in a material for the first shaft portion to obtain the first shaft portion and then a gripped section for centering is formed on the outer peripheral surface of an axially end portion of the first shaft portion on the side connected to the second shaft portion based on the first input section. The friction welding is performed by abutting the axially end portions of the first shaft portion and the second shaft portion in a state where the gripped section is gripped by a first gripping tool for centering, the first shaft portion is rotated with the first gripping tool, and the second shaft portion remains without rotating.

A method for producing a spindle nut (10) for a ball screw (12) is provided, having the following steps: providing a substantially cylindrical workpiece (50) with first and second end faces (46, 44) and a lateral surface (14), shaping the workpiece (50) by pressing in an axially symmetrical central opening (16) and by simultaneously pressing in at least one first (18) and one second (20) channel which are arranged axially in parallel in the lateral surface (14) of the workpiece (50), the central opening (16) and the channels (18, 20) being open toward the first end face (46), introducing an internal thread (34) into the central opening (16), and introducing at least two radially running through-openings (22, 24) at least into the first channel in the form of a transfer channel for receiving diverting inserts (26, 28). A spindle nut (10) produced by the method and to a ball screw (12) having such a spindle nut (10) are also provided.

A diverter for a ball return of a ball screw configured for lifting in and lifting out balls from a ball channel between the spindle nut and the threaded spindle. The diverter is configured in one piece and has 3 functional units, specifically a positioning element, a deflection element having a spade-like lifting-out region and a diverting surface for balls out of or into the ball channel. All surfaces of the diverter that are provided for guidance of balls are configured as circumferentially open grooves (not closed in the manner of a tunnel). A method for assembling such a ball return includes providing two single-piece, structurally identical diverters; providing a pre-assembled module with a spindle nut and a threaded spindle, the spindle nut having two inwardly fitted apertures; inserting the diverters into the apertures; introducing balls; and securing the ball return by attaching a covering sleeve to the spindle nut.

A method for manufacturing a steering shaft of a steering device includes: a reduced-diameter section forming process in which a second-phase member is formed from a first-phase member by forming a reduced-diameter section in the first-phase member; and a ball screw groove forming process in which a third-phase member is formed from the second-phase member by forming a ball screw groove in the second-phase member by rolling.