| 摘要 |
An actuator comprises a base (1) having a bottom wall (1a) and a pair of side walls (1b,1c) provided upright on right and left sides of the bottom wall (1a), having a transverse cross-section of an approximately U shape and formed by extrusion of a light metal or a light alloy. A slider (23) is provided inside the base (1) in such a way as to be movable along the lengthwise direction of the base (1), is made of the same type of light metal or light alloy as that of the base (1), and has a pair of return paths (65,67). A pair of base side grooves (41,43) are formed in inner surfaces of the pair of side walls (1b,1c) of the base (1). A pair of slider side grooves (53,55) are formed in right and left side surfaces of the slider (23) at positions corresponding to the pair of base side grooves (41,43), the slider grooves (53,55) having a same shape as the base side grooves (41,43). A pair of base rails (54,47) of steel are securely attached to the pair of base side grooves (41,43) and have rolling body tracks (49,51). A pair of slider rails (57,59) of steel are securely attached to the pair of slider side grooves (53,55) and have rolling body tracks (61,63) which communicate with the return paths (65,67) via a pair of reversal caps (69,71). <IMAGE> |
