A ball screw device is provided, including a retainer that can properly retain balls. The difference between a diameter being the pitch circle diameter of the ball screw device and the outside diameter of the rack shaft is set to be equal to or larger than the difference between the bore diameter of a ball screw nut and the diameter. The thickness center diameter of the retainer is set to be smaller than the diameter. Even when the inclination angle is reduced, the clearance between the inclined surfaces of each retainer groove on the radial inside can be easily set to be smaller than the diameter of the balls because the bore diameter of the retainer is set to be smaller. Thus, even when the inclination angle of the inclined surfaces is set to be smaller, the balls can be properly retained.

Provided is a ball screw capable of reducing unevenness of load distribution of balls and extending a service life of the ball screw. In the ball screw, one end part 6 of a nut 2 on a flange 2-2 side is closer to an end 9 of a screw shaft 1 on a fixed side than the other end part 7 of the nut 2 on a side opposite the flange 2-2 is, two or more circulation paths 5a to 5c are arranged in an axial direction of the nut 2, and a diameter of a ball 3a in the circulation path 5a closest to the flange 2-2 of the nut 2 is smaller than a diameter of a ball 3c in the circulation path 5c remotest from the flange 2-2 of the nut 2.

A method of manufacturing a bridge-type ball screw (1) with a bridge member (5) fit into a nut bridge window (6). The bridge member (5) has a linking groove (5a) with a rolling track that acts as a circulating path. After the bridge member (5) is fit into the nut bridge window (6), a cylindrical mandrel (8), with projections (9), is inserted into the nut (3). An upper die (10) restricts the upper surface of the bridge member (5) and is lowered while the nut (3) is held between the upper die (10) and the mandrel (8). A connection part is subject to plastic working by the projections (9) of the mandrel (8). The bridge member (5) is simultaneously deformed by the upper die (10) to secure the bridge member (5) into the nut bridge window (6).

A ball screw device includes a screw, a nut and a plurality of balls. A nut body includes an inner ring wall, a ball groove and an assembly groove. The assembly groove is axially arranged in the inner ring wall and runs through two axial ends of the nut body. Viewed from an axial end of the nut body, a shape of the assembly groove includes a narrow neck and a wide neck along a radial cross section of the nut body. A circulator is arranged in the assembly groove, where a shape of the circulator corresponds to the shape of the assembly groove, the circulator is provided with a guiding groove facing the inner ring wall, and the guiding groove and the ball groove form a ball circulating channel. The plurality of balls rolls in the ball circulating passage formed by a track groove and the ball circulating channel.

The invention relates to a ball screw including a spindle nut arranged on a lead screw, and balls, which roll on ball grooves of the spindle nut and of the lead screw, and a circumferential stop on the screw side and a circumferential stop on the nut side, the spindle nut being arranged in a sleeve surrounding the ball nut, the sleeve is formed from sheet metal by shaping and the nut-side circumferential stop is formed integrally on the sleeve.

A ball screw nut having a tubular sheet metal body with a thread profile and being optionally encapsulated in plastic. This sheet metal body is formed of a sheet metal part that includes the thread profile and a ball-returning piece inserted therein, which is designed as an additional sheet metal part.

A threaded nut for a ball screw drive is provided. The threaded nut includes a cylindrical central piece ending at a flange. A deflecting body is attached to the cylindrical central piece and is configured to recirculate balls during operation of the threaded nut. A pin fixes the deflecting body to the flange. In embodiments, the flange and the deflecting body each have recesses that are aligned with one another, and the pin extends through those recesses.

A ball screw and nut mechanism has a screw in cooperation with a nut via balls that can circulate in a raceway formed by the opposing threads of the screw and nut. The nut has a recirculation insert passing therethrough from the outer face to the thread, the recirculation insert having a first end with a ball transfer groove turned towards the screw. The mechanism has a holding body for holding the recirculation insert in the housing, the recirculation insert having a second end with a shoulder bearing on the nut, the second end of the recirculation insert having an orientation lug having an angular position predetermined and fixed relative to the ball transfer groove, the orientation lug cooperating with a guide relief of the holding body to fix an orientation of the recirculation insert such that the transfer groove is adjusted to the raceway.

A ball screw is provided in which an outer circumferential formation is formed at a portion facing a ball circulating passage out of outer circumferential surface of a nut. The ball screw includes: a screw shaft having on its outer circumferential surface a screw groove; a nut having on its inner circumferential surface a screw groove facing the screw groove; a plurality of balls rollably loaded in a spiral ball rolling passage formed by both screw grooves; and a ball circulating passage to return the balls from a start point to an end point of the ball rolling passage for recirculation. The ball circulating passage is a concaved groove formed by concaving a groove on a part of the cylindrical inner circumferential surface of the nut by plastic working. Then, a flange is integrally provided at a portion facing the ball circulating passage and the screw groove.

In a ball screw (1), the positioning of the deflectors to the nut is facilitated, and the deflectors are prevented from being dislodged in the radially outward direction from the nut. The ball screw (1) includes a screw shaft (3), a nut (7), a pair of deflectors (13) inserted in respective receiving holes (14) of the nut and a plurality of balls (8). The nut (7) is provided with a guide portion (42) configured to cooperate with a corresponding guide portion (41) provided on the deflector (13) so that the insertion of the deflector (13) into the respective receiving holes (14) is guided in a direction at an angle to the radial direction of the nut.