| 摘要 |
A gas cylinder (20, 200, 200') of the present invention comprises a rod (70, 212, 212') which is loosely or floatingly connected to the piston (102, 210) , to be movable relative to the piston by a plate (74, 278) at an end of the r od which is trapped in a bore (104, 276) in a forward end of the piston. The piston is flexible and changes shape due to pressure changes within the chamber. The sizes of the piston and the cylinder tube, in conjunction with the piston seals allow for the formation of a cushion of gas around at least a portion of the piston; and the piston floats on the gas cushion to facilitat e the low friction movement of the piston in the tube without the use of a lubricant. |
