A ball screw spline with reduced size and weight includes: a shaft formed in such a manner that a helical ball screw groove and a straight ball spline groove intersect each other; a ball screw nut having a helical ball screw groove facing the ball screw groove in the shaft, the ball screw nut being configured to allow recirculating a screw ball fitting in the ball screw groove in the shaft; and a ball spline outer race having a straight ball spline groove facing the ball spline groove in the shaft, the ball spline outer race being configured to allow recirculating a spline ball fitting in the ball spline groove in the shaft. The ball screw groove in the shaft is made as deep as or deeper than the ball spline groove in the shaft, and the screw ball is made smaller in diameter than the spline ball.

A lubricatable ball spline device includes a ball spline shaft, a ball nut slidably sleeved on the ball spline shaft and having oil guide holes, a linear bearing unit mounted between the ball spline shaft and the ball nut, a bearing ring rotatably sleeved on the ball nut and having an oil supplying hole, a positioning portion disposed between the bearing ring and the ball nut, and an oil passage corresponding to the oil supplying hole. The oil supplying hole, the oil passage, an oil storage space of the positioning portion and any one of the oil guide holes cooperatively form a continuous oil path.

A device for rotationally and translationally moving an object comprising a flat storage area relative to a storage area of a support plate arranged plane-parallel to the storage area, wherein: the object can be rotated relative to the support plate in one of two possible opposing rotational directions and can be displaced in a predefined direction; mutually facing bearing surfaces of the storage areas each have closed peripheral raceway grooves in which rolling elements are guided; the raceway grooves are formed such that, when a force is applied to the object in a direction defined in the plane of the storage area, the object can be moved, in a movement which is at least partially forcibly guided and which is simultaneously rotational and translational, from a starting position into an intermediary position, the object being rotated relative to the support plate in one of two possible opposing rotational directions and being displaced in a predefined direction; and the object, after being moved into the intermediary position, can further be rotated relative to the support plate in the one of two possible opposing rotational directions and can be displaced counter to the predefined direction, and, when rotated by 180, resumes the base position.

A device for rotationally and translationally moving an object comprising a flat storage area relative to a storage area of a support plate arranged plane-parallel to the storage area, wherein: the object can be rotated relative to the support plate in one of two possible opposing rotational directions and can be displaced in a predefined direction; mutually facing bearing surfaces of the storage areas each have closed peripheral raceway grooves in which rolling elements are guided; the raceway grooves are formed such that, when a force is applied to the object in a direction defined in the plane of the storage area, the object can be moved, in a movement which is at least partially forcibly guided and which is simultaneously rotational and translational, from a starting position into an intermediary position, the object being rotated relative to the support plate in one of two possible opposing rotational directions and being displaced in a predefined direction; and the object, after being moved into the intermediary position, can further be rotated relative to the support plate in the one of two possible opposing rotational directions and can be displaced counter to the predefined direction, and, when rotated by 180, resumes the base position.

This hollow shaft member 10 includes paired diameter-reduced sections 11 respectively formed at both shaft ends of a hollow shaft-like tubular material by performing swaging processing on both the shaft ends, and an intermediate section 12 located between the paired diameter-reduced sections, and having an outer diameter larger than an outer diameter of the paired diameter-reduced sections. Shapes of connection boundaries between the intermediate section 12 and the diameter-reduced sections 11 are formed as perpendicular step-shaped sections 13 stepped substantially perpendicular to an axial direction, and the perpendicular step-shaped sections 13 are formed by the swaging processing.

A lubricatable ball screw device includes a ball screw shaft, a ball nut slidably sleeved on the ball screw shaft and having oil guide holes, a linear bearing unit mounted between the ball screw shaft and the ball nut, a bearing ring rotatably sleeved on the ball nut and having an oil supplying hole, a positioning portion disposed between the bearing ring and the ball nut, and an oil passage corresponding to the oil supplying hole. The oil supplying hole, the oil passage, an oil storage space of the positioning portion and any one of the oil guide holes cooperatively form a continuous oil path.

The lubricating oil supply device including: a storage body, which has a large number of air gaps thereinside, and is configured to retain the lubricating oil in the air gaps; a casing, which includes an accommodating chamber for the storage body, has an opening facing the raceway shaft and opening the accommodating chamber, and is fixed to the slide member; and a coating body, which is arranged in the opening of the casing to be held in abutment against the raceway shaft, and receives the lubricating oil to be supplied from the storage body, wherein the storage body has a cutout portion corresponding to the opening of the casing, and wherein the coating body has an air gap ratio smaller than an air gap ratio of the storage body and is sandwiched in the cutout portion of the storage body to push outward the cutout portion.

A ball screw device includes a nut including a nut main body and a cover, a screw shaft, a rolling path formed by a screw groove of the nut main body and a screw groove of the screw shaft, a circulation path formed by an outer circumferential surface of the nut main body and the cover, a pair of connection paths that allow one end of the circulation path and one end of the rolling path to be communicated with each other and allow the other end of the circulation path and the other end of the rolling path to be communicated with each other, respectively, and a large number of balls disposed in the rolling path, the circulation path, and the pair of connection paths. The circulation path is formed along a cylindrical path of the outer circumferential surface of the nut main body.

A ball screw device includes a nut including a nut main body and a cover, a screw shaft, a rolling path formed by a screw groove of the nut main body and a screw groove of the screw shaft, a circulation path formed by an outer circumferential surface of the nut main body and the cover, a pair of connection paths that allow one end of the circulation path and one end of the rolling path to be communicated with each other and allow the other end of the circulation path and the other end of the rolling path to be communicated with each other, respectively, and a large number of balls disposed in the rolling path, the circulation path, and the pair of connection paths. The circulation path is formed along a cylindrical path of the outer circumferential surface of the nut main body.

An actuator assembly comprises a static part and a movable part. A helical bearing arrangement supporting the movable part on the static part guides helical movement of the movable part with respect to the static part around a helical axis. One or more actuators, that are not shape memory alloy actuators, are arranged to drive movement of the movable part around the helical axis, which thereby includes a component of translational movement along the helical axis. The helical movement increases the force within the actuator assembly allowing actuation of heavier movable parts, and may improve posture.