| 摘要 |
An object of the present invention is to provide an electric linear actuator intended to reduce weight of the housing and to improve durability of the housing with increasing the strength against load applied to the housing. According to the present invention, there is provided according to the present invention of claim 1, an electric linear actuator comprising a housing; an electric motor mounted on the housing; a speed reduction mechanism for reducing rotational speed of the electric motor via a motor shaft; and a ball screw mechanism for converting rotational motion of the electric motor transmitted via the speed reduction mechanism to 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 rolling bearings mounted 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 the helical screw groove of the nut, inserted into the nut via a large number of balls, and supported axially movably but not rotationally, characterized in that the housing comprises a first housing on which the electric motor is mounted and a second housing to be abutted against an end face of the first housing, and that at least one of the first and second housings is formed with ribs extending from each of securing portions arranged on the periphery of the housing through which fastening bolts are inserted to a containing portion for containing the screw shaft. |
