| 摘要 |
PURPOSE:To obtain a high mechanical efficiency for an actuator in which a cylindrical output rod is fitted onto the outer periphery of a screw shaft adapted to be rotated, by providing thrust pads on both surfaces of a housing through which the output rod pierces, corresponding to compression load and tension load exerted to the output rod. CONSTITUTION:An actuator preferable for a cab tilting device in a cab-over type large-size vehicle, gas a screw shaft 2 which is rotated in association with the rotation of a motor 8 through a reduction gear mechanism 6, and the output rod 10 is elevated in the axial direction in association with the rotation of the screw shaft 2 by means of a ball screw 16. In this arrangement, a recess 26a is formed in the bottom surface of a gear 26 in the screw shaft 2, and an annular member 36 fitted onto the screw shaft 2 is disposed in the recess 26a. Further, a thrust bearing 37 is disposed between the gear 26 and the annular member 36, and an one-way clutch 38 is located on the screw shaft 2 on the inside of the annular member 36. Further, thrust pads 46, 47 are disposed between the annular member 36 and a housing 4 and between a ring 42 fixed to the lower end of the screw shaft 2 and the housing 4, respectively. |
