Patent ID: 7526993

Claim:
A fluid pressure cylinder apparatus having a throttle valve, comprising: a piston moving in an inner part of a cylinder body by action of fluid pressure; a pressure chamber for exerting the action of the fluid pressure on the piston; a port for supplying or discharging a pressurized fluid to the pressure chamber; and a variable throttle valve for adjusting a flow of the pressurized fluid so as to control a movement of the piston, wherein the variable throttle valve includes a cylindrically shaped valve rod housed in a circular valve hole formed in the cylinder body in a condition of being hooked in a direction of a center axis line of the valve hole, while being rotatable around the center axis line, wherein the valve hole comprises a relatively small diameter hole portion with a fixed hole diameter and a relatively large diameter hole portion with a fixed hole diameter, and a first flow path hole and a second flow path hole through which the pressurized fluid passes that are opened at a side face and a bottom face of the small diameter hole portion, wherein the valve rod comprises a main shaft portion having a relatively small diameter, which fits into the relatively small diameter hole portion of the valve hole, and an operating portion having a relatively large diameter, which fits into the relatively large diameter hole portion of the valve hole in a non-protruding condition, and the valve rod is configured such that an outer peripheral surface of the main shaft portion is formed to be in close sliding contact with an inner peripheral surface of the small diameter hole portion, a connecting hole including a first hole opening at one end is opened at a side face of the main shaft portion and is allowed to communicate with the first flow path hole, and a second hole opening at the other end is opened at a bottom face of the main shaft portion and is allowed to communicate with the second flow path hole is formed in an inner part of the valve rod, the valve rod further comprising a flow adjusting groove for adjusting a connected square measure of the first flow path hole and the first hole opening along with a rotating operation at an outer periphery of the main shaft portion of the valve rod, and an operating hole in which a tool is inserted when performing the rotating operation at a top face of the operation portion, and wherein the flow adjusting groove extends in a circumferential direction from a position of the first hole opening as a base end and a groove width gradually narrows toward a tip end side and a groove depth gradually shallows at the same time.