| 摘要 |
<p>A valve is disclosed for connecting a user port with a pressure port or a return port as required. A closure member which is acted upon by a pressure piston is shifted from a first into a second valve position. By disposing a throttle in the return port, a balanced pressure is achieved on all sides of the closure member during a valve position change process so that the valve changes from the first into the second position safely and rapidly.</p> |
