| 摘要 |
<p>A balance valve for maintaining two fluid pressure systems at a predetermined pressure relative to one another. The valve comprises a piston (2) slidably received within a bore (14), and subjected on opposite ends to the pressure in the two systems. Each of the systems is provided with a relief line (17, 20) whose communication with the associated system is controlled by movement of the piston such that any imbalance of forces acting on the piston causes the piston to be displaced to open the appropriate relief line to balance out the forces acting on the piston. Shock absorber means (25, 26, 28, 29) is provided to resist rapid movement of the piston, and respective springs (23, 24) may be provided for the purpose of centralizing the piston or for setting up a differential pressure in the two systems. The ports (21) of the respective relief lines are preferably triangular in shape such that a progressively greater area is uncovered in relation to the distance travelled by the piston.</p> |
