To reduce the number of thrust bearings receiving a thrust load and also reduce a torque loss in an electrically-driven linear actuator employing planetary rollers.
The electrically-driven linear actuator includes a center shaft 11, an outer ring member 5 arranged outside the center shaft and a plurality of planetary rollers 24 assembled between the center shaft and the outer ring member, where one of the center shaft and the outer ring member is an input member that is rotatably but axial non-movably supported and also rotationally driven by an electric motor 12, and the other of the center shaft and the outer ring member is an output member that is non-rotatably supported but axially movable. A plurality of annular projections 25 arranged at an equal pitch are provided at the peripheral outer surface of the input member, the outer peripheral surface of the planetary roller is provided with an annular groove into which the annular projection is fitted, the peripheral surface of the output member is provided with a helical projection which fits into the annular groove of the planetary roller. The planetary rollers are revolved at an axial fixed position with respect to the input member while being rotated through the rotation of the input member, and the output member is axially moved through revolution of the planetary rollers.
| JPH09250579A | 1997-09-22 | |||
| JP2008002587A | 2008-01-10 | |||
| JP2011241851A | 2011-12-01 | |||
| JPS5465262A | 1979-05-25 | |||
| JPS50128058A | 1975-10-08 | |||
| JP2005133863A | 2005-05-26 | |||
| JP2010007791A | 2010-01-14 |
| WO2012098977A1 | 2012-07-26 |
Naoya Kamata
Yaichiro Nakatani
Takashi Shimizu