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 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 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 grease composition which is excellent in seizure resistance can be provided without deteriorating resistance to stirring in the rolling device, and a rolling device in which the grease composition intervenes to a predetermined portion can be also provided by use of a grease composition comprising a base oil and a thickener, the thickener being a diurea compound obtained by allowing an amine mixture comprising alkylphenylamine, an alkyl group of which has 8 to 16 carbon atoms, and cyclohexylamine, to react with a diisocyanate compound, the amount of cyclohexylamine in the amine mixture being 80% by mole or more and less than 91% by mole, and a worked penetration being 300 to 330.

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.

A rolling guide apparatus is disclosed, which has a first member 1, a second member 2 and a rolling body unit 5 disposed between the first member 1 and the second member 2, the second member being movable along the first member 1 upon rolling of the rolling body unit 5, the apparatus including: a guide path G of the rolling body unit 5 being configured to have: a rolling path R configured to have a rolling groove la formed in the first member 1 and a rolling groove 3a, formed in the second member 2, in a face-to-face relationship with the rolling groove la of the first member 1; and a circulation path C provided in the second member 2 and 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 easy to be assembled and capable of performing stable operations is thereby provided.

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.

A rolling device includes: an inner member that has a raceway face; an outer member that has a raceway face facing the raceway face; and rolling elements that are disposed between both raceway faces in a rollable manner, wherein at least one of the inner member and the outer member has a space formed therein. Further, a method for manufacturing a rolling device including an inner member that has a raceway face, an outer member that has a raceway face facing the raceway face, rolling elements that are disposed between both raceway faces in a rollable manner, and a space that is formed inside at least one of the inner member and the outer member by a 3D printer.

The ball reflow component includes a ball cage, a first end cover, and a second end cover. The ball cage includes a long groove, a first recessed portions, a second recessed portions, a first side portion, and a second side portion corresponding to the first side portion. The first recessed portions and the second recessed portions are arranged on the first side portion and the second side portion, respectively. The first end cover is assembled on the first side portion. The first end cover includes a first curve and first protruding portions, and the first protruding portions are correspondingly arranged in the first recessed portions. The second end cover is assembled on the second side portion. The second end cover includes a second curve and second protruding portions, and the second protruding portions are correspondingly arranged in the second recessed portions.

A steering device that holds a steering member in such a manner that the steering member is movable between an advanced position where a driver can steer the steering member and a retracted position located closer to the front of a vehicle. The steering device includes: a fixed member attached to a vehicle body; a movable member to which a steering shaft holding the steering member is rotatably attached; and an upper guide mechanism and a lower guide mechanism that linearly guide the movable member with respect to the fixed member. An end on the advancing side of the upper guide mechanism is located further toward the advancing side than an end on the advancing side of the lower guide mechanism in an advancing and retracting direction of the movable member.