Nsk Corporation

Ryo Segawa

Kazutaka Tanaka

Yasumi Watanabe

Tomoko Miyamori

The ball screw device has a nut having a guide concave groove on the outer-circumferential surface capable of engaging with a rotation restraining member in the circumferential direction, a housing provided with an insertion hole having a retaining concave groove on the inner-circumferential surface capable of engaging with the rotation restraining member in the circumferential direction, the rotation restraining member configured by a shaft-shaped member extending in the axial direction, the rotation restraining member having an outside portion in the radial direction arranged inside the retaining concave groove and an inside portion in the radial direction arranged inside the guide concave groove, so as to be able to slide in the axial direction.

Ball screw device

A ball screw device has a screw shaft that has a screw portion having a spiral-shaped shaft-side ball screw groove on an outer peripheral surface thereof, and a carrier integrally formed with the screw portion and constituting a planetary speed-reducing mechanism; a nut that has a spiral-shaped nut-side bass screw portion on an inner peripheral surface thereof; a plurality of balls arranged between the shaft-side ball screw groove and the nut-side ball screw groove; and a rolling bearing for supporting the carrier which has an outer ring having an outer ring raceway, an inner ring raceway provided on a portion facing the outer ring raceway in a radial direction, and a plurality of rolling bodies arranged between the outer ring raceway and the inner ring raceway, which is directly formed on an outer peripheral surface of the carrier.

Ball screw device and manufacturing method of screw shaft

The nut has a first fitting surface provided with a first retaining ring groove on an end portion on the other side in the axial direction; the fitting cylinder, at an end portion on the one side in the axial direction, has a second fitting surface provided with a second retaining ring groove in a portion facing the first retaining ring groove with regard to a radial direction; and the retaining ring is engaged so as to span between the first retaining ring groove and the second retaining ring groove.

Ball screw device and manufacturing method thereof

A ball screw device has: a screw shaft rotationally moving during use, a nut having a protruding non-rotating side engaging portion at an end portion on one side in an axial direction, the nut linearly moving during use, balls arranged between a shaft-side and nut-side grooves, and a driving member fixed to the screw shaft having an arc-shaped rotating-side engaging groove portion into which the non-rotating side engaging portion can be inserted in the axial direction, and which can be engaged with the non-rotating side engaging portion in a circumferential direction.

A ball screw device comprising: a screw shaft, a nut, balls arranged between the shaft-side ball thread groove and the nut-side ball thread groove, a stopper including: a boss portion fitted to the fitting shaft portion of the screw shaft, and a second engaging portion protruding in the radial direction from the boss portion and engageable with a first engaging portion of the nut in the circumferential direction, and a holding member arranged adjacent to one side in the axial direction of the stopper, such that an axial load can be transmitted between the screw portion of the screw shaft and the holding member through the stopper without applying a moment to the stopper.

Ball screw device and method for manufacturing same

A ball screw device having a screw shaft rotating during use, a nut moving linearly during use, balls, a fitting cylinder fixed to the nut, a housing, and an anti-rotation member, a first member, which is one of the nut and the fitting cylinder, having a retaining concave portion engaging with a radially inner portion of the anti-rotation member and including a closed surface, an insertion hole of the housing having a guide concave groove engaging with a radially outer portion of the anti-rotation member, the radially inner portion held between the closed surface and an axially end surface a second member, which is the other of the nut and the fitting cylinder, the radially outer portion being able to slide in the guide concave groove.

Growing community of inventors

Fujisawa, Japan

Ryo Segawa