The present invention provides a rack assist type electric power steering apparatus. The power steering apparatus includes: a ball nut coupled to a rack bar via balls to be rotated, and configured to cause the rack bar to slide; a bearing mounted on an outer peripheral surface of the ball nut so as to support rotation of the ball nut; and a support member coupled to at least one of a space between one side of an outer race of the bearing and a housing and a space between the other side of the outer race of the bearing and the housing so as to support the bearing.

A ball spline with detour tracks includes spline shaft, nut part movable along a longitudinal direction of the spline shaft, and balls between the nut part and the spline shaft, wherein the nut part includes nut adapted to insert the spline shaft thereinto and retainers on longitudinal sides of the nut, the spline shaft includes tracks extended along the longitudinal direction, the nut includes load track grooves formed in longitudinal direction on inner peripheral surface into which the spline shaft is inserted and non-load circulating portions formed in the longitudinal direction, each retainer includes circulating grooves on the inner peripheral surface to face the load track groove and non-load circulating portion, the balls run between the tracks and the load track grooves, and each track includes track groove formed in longitudinal direction of the spline shaft and detour tracks whose longitudinal sides are connected to the track groove.

The present invention relates to a ball spline having a reinforcement bush part, comprising: a rod-shaped spline shaft having at least one concave track groove formed to extend along the longitudinal direction thereof; a nut part in which the spline shaft is inserted and movable along the longitudinal direction thereof; and a plurality of balls provided between the nut part and the spline shaft to circulate, wherein: the nut part includes a nut which is a hollow body into which the spline shaft is inserted, and retainers which are hollow bodies which are provided at longitudinally opposite sides of the nut and into which the spline shaft is inserted; at least one spline part and at least one reinforcement bush part are provided at the nut part; some of the balls change direction in spline circulation grooves of longitudinally opposite side retainers and circulate and move between a track groove and a load track groove and along a no-load circulation part; and the others of the balls roll while being in contact with the outer surface of the spline shaft, and circulate and move along the reinforcement bush part.

A motion guide apparatus is provided which can prevent a ball from contacting an edge of a ball rolling groove of a track member when the ball transfers from a rolling surface of the inner peripheral side of a turn-around path (an inner peripheral-side component) to the track member. The motion guide apparatus includes: a track member (2) including a ball rolling groove (2a); and a moving member assembled to the track member (2) in such a manner as to be movable relative to the track member (2). The moving member includes: a moving member body having a loaded ball rolling groove facing the ball rolling groove (2a), and a return path substantially parallel to the loaded ball rolling groove; and a lid member having a turn-around path. In cross section of the motion guide apparatus perpendicular to a length direction of the track member (2), letting the radius of curvature of the ball rolling groove (2a) be R, and letting the distance from a ball center (O) to a rolling surface (21) of the inner peripheral side of the turn-around path (an inner peripheral-side component (9a)) be r, R>r is set.

The present disclosure relates to a ball spline device, an automated guided vehicle and a stereoscopic warehouse system. The ball spline device includes: a spline shaft, an outer side wall of which is provided with a raceway groove extending along an axial direction, the raceway groove includes a first groove section and a second groove section communicated along the axial direction, a width of the second groove section being greater than the width of the first groove section; a spline nut coaxially, sleeved outside the spline shaft; and a first rolling body, movably disposed in the raceway groove along the axial direction to achieve relative movement of the spline nut and the spline shaft. When the spline nut is in a first position, the first rolling body is in the first groove section, and cooperates with the first groove section in a constrained manner to cause synchronous rotation of the spline nut and the spline shaft; and when the spline nut is in a second position, the first rolling body is in the second groove section, so that there is a predetermined gap in a circumferential direction between the spline shaft and the spline nut.

A threaded shaft for a ball screw comprising: a shaft of fibre-reinforced polymer material; and a helical ridge formed on an outer surface of said shaft, said helical ridge being formed from a fibre-reinforced polymer material comprising a plurality of helical fibres wound around the shaft in the same sense and grouped together to form the ridge. The helical ridge formed from grouped helical fibres all wound with the same sense provides excellent axial load carrying capability as the fibres run continuously from end to end of the shaft and can thus transmit load from end to end. This adds much greater strength than a shaft formed from plastics only. The load carrying capability of the fibre wound helical ridge can indeed approach that of existing metal threads while still being much lighter in weight.

A threaded shaft for a ball screw comprising: a shaft of fibre-reinforced polymer material; and a helical ridge formed on an outer surface of said shaft, said helical ridge being formed from a fibre-reinforced polymer material comprising a plurality of helical fibres wound around the shaft in the same sense and grouped together to form the ridge. The helical ridge formed from grouped helical fibres all wound with the same sense provides excellent axial load carrying capability as the fibres run continuously from end to end of the shaft and can thus transmit load from end to end. This adds much greater strength than a shaft formed from plastics only. The load carrying capability of the fibre wound helical ridge can indeed approach that of existing metal threads while still being much lighter in weight.

A rolling guide apparatus having a first member 1, a second member 2, and a rolling body unit 5, the apparatus including a guide path G of the rolling body unit 5 including a rolling path R configured to have a rolling groove 1a and a rolling groove 3a, and a circulation path C allowing communication between a start point and an end point of the rolling path R, the rolling body unit 5 being configured to have a plurality of first rolling bodies 5a and a plurality of second rolling bodies 5b each composed of an elastic material, at least one second rolling body 5b being always positioned in the circulation path C. The rolling guide apparatus is easy to be assembled and is capable of performing stable operations.

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 screw nut on which a pulley is mounted is capable of promoting reductions in the size and weight thereof. The screw nut includes: an outer ring; and a nut rotatably assembled to the outer ring via a first rolling element. The nut includes: a nut body having a screw groove in an inner surface thereof; and a recirculation component provided at an end portion of the nut body in an axial direction, the recirculation component having a turn-around path for recirculating a second rolling element rolling along a screw groove. A pulley to be mounted on the nut is fitted on an outer surface of the nut body, and is brought into contact with an end surface of the nut in the axial direction. The pulley is mounted on the end surface of the nut with a fastening member.