| 摘要 |
<p>The automatic control slows a liquid leak in a pipe. It monitors pressure downstream of a block valve (2) when closed and this valve is closed when liquid flow ceases. A Venturi effect is used to keep the valve open while liquid flows. Downstream pressure drop, when the valve is closed, deforms a membrane (5) to which it is fixed and closes an orifice (15). A secondary valve (7) is actuated by a permanent magnet (9) and held closed. The magnet can fit into a recess (28).</p> |
