| 摘要 |
A piston rod (5) is formed in a diameter smaller than an inner diameter of a hollow cylinder (1). The piston rod (5) is inserted in the cylinder (1) so as to be relatively movable in an axial direction of the cylinder (1). A locking mechanism (30) comprises a first surface (31) provided on the inner surface of the cylinder (1), a plurality of second surfaces (32) arranged in an axial direction of the piston rod and parallel to one another (5), and a locking member (36). The first surface (31) is so inclined that the inside diameter of the cylinder (1) gradually increases toward one end of the cylinder (1). Each second surface (32) is so inclined that the diameter of the piston rod (5) gradually increases to the one end of the piston rod (5). The locking member (36) is held between the first surface (31) and any one of the second surfaces (32) to lock relative movement of the piston rod (5) with respect to the cylinder (1). <IMAGE> |
