| 摘要 |
<p>The meter 2, e.g. a gas meter includes an inlet boss 4 providing an unregulated supply of gas via a valve means 8 which regulates the flow of gas as it passes into a chamber 6. The valve means 8 forms part of a governor which is formed integral with the gas meter. The valve means 8 includes a valve stem 12 which has a bore 18 extending throughout the length of the valve stem. The valve stem passes through the chamber 6 and through a first diaphragm 22 to which it is sealably connected and is terminated on the surface of second diaphragm 34. The first diaphragm 22 separates second and third chambers 24, 28, the second chamber 24 being in communication with the first chamber 6. The third chamber 28 is connected via the bore 18 in the valve stem 12 to the unregulated gas supply. The second diaphragm 34 separates fourth and fifth chambers 32,38, the chamber 38 is vented to the atmosphere. In normal operation the chamber 32 is connected by a control valve 46 to the chamber 6, and the various balance of forces through the governor allow the gas supply to be regulated. The control valve 46 when operated by a solenoid 48 into a second position causes the chamber 32 to be connected to the chamber 28 and the inlet pressure is communicated via the conduit 54, 50 to the chamber 32 causing the governor to shut off the gas supply. <IMAGE></p> |
