| 摘要 |
<p>A valve assembly comprises a valve body 7, an obturator 2 rotatably mounted in the body and a transducer 15 connected to or located adjacent the obturator in order to determine the position thereof. The transducer may comprise e.g. a potentiometer or a Hall effect device. The transducer 15 is held in position by screws 14 on an adjustable member 12 that is locked in position by nut 17. A potentiometer spindle 19 is in two parts joined by a sleeve 30 to allow for adjustments. The end of the spindle is connected to a plastics flexible coupling 16 which is adhered to the obturator 2. The potentiometer may be replaced by a Hall effect device with a sensor adjustment mechanism (41) Fig. 2 retained in member (12) and connected via a spindle (19) to a sensor (43) located in a central hole (44) of a magnetic disc or annulus (40). The arrangement is applicable to a ball valve, Figs. 3 - 6, or a tapered plug valve, Figs. 7 and 8. <IMAGE></p> |
