Device to indicate operating state of a linear actuation valve

摘要

A device 3 for indicating the operating state of a linear actuation valve (5) comprises a mounting plate (9) having a rectilinear slot (11) therein for slidably receiving a perpendicularly extending follower stem (6) fixed to a follower nut (4). The nut (4) is threaded on to the exterior of a sleeve (7) which is mounted for conjoint rotation with the hub of a hand wheel (2) of the linear actuation valve. Engagement of the follower stem (6) with the slot (9) prevents rotation of the nut (4) and provokes it to move axially relative to the sleeve (7). The mounting plate (9) also includes means for fixing sensors (15) and (16) to the plate for detecting arrival of the follower stem (6) moving along the slot in either of two positions to be detected.