| 摘要 |
<p>PURPOSE:To prevent the entry of compressed gas from a gas chamber into a fluid chamber by providing between a cylinder and a piston a pressure fluid chamber filled with pressure fluid which surrounds the piston. CONSTITUTION:Between two T-rings 18 surrounding a piston 6, a ring groove 22 is made, and a pressure fluid chamber 24 is formed between the ring groove 22 and the inside surface of a cylinder section 15. Moreover, a small piston 26 is air and fluid tightly fixed in the closed-end round hole made on the gas chamber 16 side of the piston 6, and the closed-end hole internal space is connected to the pressure fluid chamber 24 by use of a through-hole 28 and it is filled with oil. And the small piston 26 is pressed not only with the gas in the gas chamber 16 but also with the force of a spring 32, and therefore the fluid pressure in the pressure fluid chamber 24 is higher than the gas pressure in the gas chamber 16, reversing the pressure gradient; thus the leakage of gas can be prevented.</p> |
