| 摘要 |
PURPOSE:To take foreign matter in concave portions and to prevent a sliding surface from being damaged by foreign matter by disposing concave portions in the sliding surface of a rod guide for a piston rod in such a manner not to be connected with at least one of both upper and lower edges of the sliding surface. CONSTITUTION:A shock absorber 1 comprises a cylinder 3 fixed in an outer shell 2, a piston rod 7 inserted in the cylinder 3 through a guide 6, and a piston 9 fixed to the lower end of the rod 7. In this arrangement, there are provided concave portions 10 in the sliding surfaces between the inner peripheral surface of the cylinder 3 and a piston ring 9 and between the outer peripheral surface of the piston rod 7 and a guide bush 6a. The concave portions 10 are formed with a depth and a width sufficient to accomodate cutting powder produced from the sliding surface or foreign matter in the operation oil. The concave portions 10 are disposed in such a manner not to be connected with an least one of both upper and lower edges of the sliding surface 10, for example, a plurality of circular cavities are uniformly disposed on the sliding surface. |
