| 摘要 |
<p>This invention relates to a butterfly valve (1) incorporating means for accurately sensing the position of the valve disc (3) within the valve body (2). One or two coils (6,7) are embedded within the valve seal (5). A current is generated within one of the coils (6) and a sensor (10) connected either to the same coil (6) or the other coil (7) measures the change in induction characteristics of the coil (6 or 7) as the disc (3) is moved. The signal sensed by the sensor (10) is indicative of the disc (3) position. <IMAGE></p> |
