A ball screw device includes a screw shaft having a first thread groove on an outer peripheral surface and a nut having a second thread groove provided on an inner peripheral surface, a notch provided on an end face, and a return hole provided on a bottom surface of the notch orthogonal to an axial direction of the screw shaft and passing through in the axial direction. An end deflector fits into the notch. The nut includes a curved surface portion at a position of a lateral surface of the notch between the second thread groove and the return hole. In a first section, the curved surface portion includes a portion that draws an arc centered at a point positioned outside the second thread groove in a radial direction around a rotation axis of the nut.

An end deflector includes a main portion including a ball delivery path that delivers balls between a rolling path and a ball return path, a tongue portion that guides the balls from the rolling path to the ball delivery path, and a pair of protruding pieces, that extend in the circumferential direction of each nut body from either side of the tongue portion with respect to the axial direction and define a ball guide groove that extends between the ball delivery path and the rolling path in cooperation with an inner circumferential surface of a deflector holding recess formed in a nut body, the main portion has an outer circumferential surface which opposes an inner circumferential surface of the deflector holding recess in the radial direction, a front-side portion of the outer circumferential surface with respect to a direction of insertion into the deflector holding recess is offset inward in the radial direction, and at least a rear-side portion of the outer circumferential surface with respect to the direction of insertion into the deflector holding recess is fitted to the inner circumferential surface of the deflector holding recess.

A nut includes a circulation passage such that balls are circulated through the circulation passage from a first axial end part of rolling raceway to a second axial end part of the rolling raceway. The nut includes a nut body, and end members connected to the opposite axial ends of the nut body. The nut body includes a first member and a second member. The first member includes a second spiral groove on the inner periphery of the first member and a passage having a groove shape opened radially outwardly, the passage being formed on the outer periphery of the first member such that the passage constitutes part of the circulation passage. The second member is placed radially outwardly from the first member and closes the passage from its radially outer side.

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.

A linear motion device and a linear motion device component are provided. The linear motion device includes a screw, a nut, an end cover, and a scrape plate. The nut is fitted over the screw, and a spiral outer groove of the screw and a spiral inner groove of the nut correspond to each other to form a ball groove. The end cover is fixed to the nut. A first through hole portion is defined through the end cover and corresponds to the nut. An engaging groove is arranged on a first surface of the end cover. The scrape plate is assembled with the end cover. A second through hole portion is defined through the scrape plate and corresponds to the nut. An engaging member is arranged on the scrape plate and assembled with the engaging 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.

A ball screw device includes a threaded shaft, a nut, and balls. The nut body includes a central tubular portion and an end tubular portion. The central tubular portion has a through-hole and an end surface. The nut further includes a circulation member and a snap ring. The circulation member is provided on an inner peripheral side of the end tubular portion such that the circulation member is in contact with the end surface. The snap ring is fitted to a circumferential groove provided on an inner periphery of the end tubular portion. The snap ring is configured to fix the circulation member in a manner such that the circulation member is sandwiched between the snap ring and the end surface.

Provided is an electric actuator (1), including: a motor (10); a motor case (11) configured to accommodates the motor (10); and a motion conversion mechanism (22) configured to convert a rotary motion generated through drive by the motor (10) into a linear motion in a direction parallel to an output shaft (10a) of the motor (10). The motion conversion mechanism (22) includes a movable part (22, which is arranged in parallel with the output shaft (10a) and is configured to perform the linear motion. The movable part (22) and the motor (10) overlap one another in a radial direction of the motor (10). A sensor target (73) is arranged in the moveable part 22, and a non-contact sensor (70) configured to detect a position of the sensor target (73) in a linear motion direction in a non-contact manner is arranged in the motor case (11).

A bass screw can move balls smoothly in a return path of a circulating component. The ball screw includes: a screw shaft having a helical ball rolling groove on an outer peripheral surface thereof; a nut having a helical loaded ball rolling groove facing the ball rolling groove, on an inner peripheral surface thereof; a circulating component where at least part of a return path connecting one end and the other end of the loaded ball rolling groove of the nut is formed; and a plurality of balls that can circulate. A contact portion that contacts the ball at two or more points is formed on an outer peripheral side of the return path of the circulating component. The contact portion of the circulating component is twisted in accordance with a change in the direction of a centrifugal force that acts on the ball.

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.