To efficiently exchange an oiling member by furnishing a clip provided to the side of a guide rail from a rotational support part supporting a back surface part end part positioned on a back surface of a holding body free to rotate free to connect and disconnect and to clamp and hold the holding body and the bracket.

A fastener 6 is a rotational support part to support a back surface part end part positioned on a back surface toward a guide rail of a holding body 7 on a bracket 5 by a nut 6a and a coil spring 6b free to rotate. Additionally, a grip part 9 is provided to the side of the guide rail from this rotational support part free to connect and disconnect and clams and holds the holding body 7 and the bracket 5. This grip part 9 has pieces, and both of the pieces are constituted to displace in the direction to draw each other, and as they fix the holding body 7 and the bracket 5 with the rotational support part, it is possible to extend an area to add clamping force. The holding body 7 does not tilt even when impact force is applied on it, and exchange of an oiling member can be carried out by extracting the grip part 9 and revolving the holding body 7.