| 摘要 |
<p>PROBLEM TO BE SOLVED: To enhance an operation rate by simplifying the switching means of a two way switching valve while maintaining its precision, and by reducing cost and frequency of changing components. SOLUTION: This pump is equipped with a pair of cylinder cases 1, 2, a pump head 15 having an entrance 9 and an exit 8, expansion members 3, 4 disposed in each cylinder, a shaft 5 coupling the free end side of each expansion member, a two way switching valve to force-feed driving fluid to each cylinder by switching fluid supplied and exhausted to a driving compartment, and a switching means to switch the actuating direction of the two way switching valve. The switching means is brought into an open condition when pushed by the free end side of the expanded expansion member among both expansion members, and is composed of pressure reducing switching valves 42A, 42B to exhaust the switching fluid introduced into the valve body to the inside of the cylinder. The entrance of the pressure reducing switching valve is connected to a corresponding driving compartment of the two way switching valve, and a pressure difference is formed in each driving compartment by the pressure reducing switching valve side opened by expansion of the expansion member and the pressure reducing switching valve side maintaining a closed condition by contraction of the expansion member.</p> |
