| 摘要 |
<p>The valve comprises a body (2, 2a) with an inlet connector (11) and an outlet connector (13) for connection to a pressure source and a pneumatic circuit respectively, and with an obturator valve (19, 20) which controls communication between the connectors (11, 13). The valve (19, 20) has a control device including a piston (23) sealingly slidable in a guide portion (2a) of the body (2) between a first chamber (32) which can be put into communication with a pressure source and a second chamber (33) housing a valve (19, 20), so that the piston (23) can move and open the valve (19, 20) under the effect of the pressure in the first chamber (32). The guided portion (23c) of the piston (23) is generally cylindrical and has a smaller cross-section than the passage cross-section of the guide portion (2a) of the body (2). An intermediate member (40) is sealingly interposed between the guided portion (23c) of the piston (23) and the guide portion (2a) of the body. The intemediate member has stop means (40a) and is locatable between the wall (2a) of the body and the guided portion (23c) of the piston (23) in the first or second orientations, in which the stop means (40) respectively allow and prevent the movement with the piston (23) under the effect of the pressure in the chamber (33).</p> |
