摘要 |
<p>The invention relates to a pressure relay comprising inside its body, and besides a distributor device with a pressure inlet, an outlet and an exhaust, an auxiliary conduit of large cross-section which is connected with a control input of the said distributor device and comprises means to mount the said body on the jack, and to receive a pipe fitting supplying pressure to a jack. The invention finds an application for signalling the outermost positions of a jack piston, or in combination with branch-pipe type jacks.</p> |