Angular displacement measuring system for valve disc - has programme disc on stem with film having light reflecting section of white paint or metallised layer

摘要

The angular displacement measuring system, can be used to monitor the position of a control valve. The rotating valve element is made with a light reflecting programme zone which also rotates. The longitudinal direction of the zone corresponds to the circumferential direction of the rotating element. The width is variable and will therefore indicate the angular position of the rotating element. The rotating element can be the valve stem (10) or an extension. The programme zone consists of a disc (14) which rotates with the shaft. A film (15) is stuck onto one of the surfaces, and has a light reflecting zone (16).