| 摘要 |
<p>A liquid flow control valve has a valve body (10) in which is mounted a valve member (41) moveable between valve open and closed positions. A turbine (15) senses liquid flow through the valve body (10) and generates electrical pulses which are counted by a control circuit, over a pre-set period. An electro-magnet (54, 55) controls operation of the valve member (41) and is driven by the control circuit so as to close the valve in the event that flow continues for longer than the pre-set period or the flow is greater than at a pre-set rate. The valve may also be closed should the temperature fall to about 0 DEG C.</p> |
