| 摘要 |
<p>A fluid pistol device including a cylinder (14), a piston 22 axially movable within the cylinder and dividing it into first and second chambers (28, 30). Mounted on the piston within the first chamber (28) is a pressure responsive valve (82) which can close off passages (52) passing through the piston. A spring loaded plunger (72) is urged against the valve (82) which in turn is urged downwardly by a lighter spring (86) towards the seated position. The arrangement is such that a piston can operate in a low force rapid movement mode in which the valve is open and fluid passes from the second chamber to the first chamber readily, a moderate force rapid movement mode in which the valve floats and still allows this passage of fluid and a high force movement mode in which fluid pressure in the first chamber holds the valve firmly seated.</p> |
