Patent ID: 6652212
Filing Date: 2003-11-25
Classification: F15B,H01L,Y10S,Y10T

Abstract:
A cylinder having a piston rod which moves to and stops at four positions with the pressure of fluid applied to a piston through two fluid ports, comprising;a spring receiving member placed coaxially with said piston rod in a piston room of a cylinder tube so that the movement of said spring receiving member is limited by one end of said piston room; a first spring member to separate said spring receiving member from said piston; a stopper formed on said piston rod to limit said spring receiving member from moving in the opposite direction to said piston; a hollow formed on the periphery of said piston rod at farther position from said piston than said stopper; and a stop pin installed in said cylinder tube to be pressed in the direction of said hollow by a second spring member to engage with said hollow, wherein the movable length of said piston rod while said stop pin is engaged with said hollow is larger than a movable distance of said spring receiving member from said piston.