| 摘要 |
An object of the present invention is to provide an electric linear actuator having high rotational performance which can prevent the operation lock of the ball screw and can be manufactured at a low cost. According to the present invention, there is provided an electric linear actuator comprising a housing; an electric motor mounted on the housing; a speed reduction mechanism for transmitting the rotational power of the electric motor to a ball screw mechanism via a motor shaft with reducing a motor speed; and the ball screw mechanism for converting the rotational motion of the electric motor transmitted via the speed reduction mechanism to an axial linear motion of a driving shaft; the ball screw mechanism comprising a nut formed with a helical screw groove on its inner circumference and supported by bearings on the housing rotationally but axially immovably, and a screw shaft coaxially integrated with the driving shaft, formed with helical screw groove on its outer circumference corresponding to helical screw groove of the nut, adapted to be inserted into the nut via a large number of balls, and supported on the housing rotationally but axially immovably characterized in that an output gear forming part of the speed reduction mechanism is secured on the nut; and that the bearings are arranged at either side of the output gear and mounted on the housing via a washer formed of ring-shaped elastic member. |
