Valve piston position monitoring device - has detector opposite grooves on spindle connected by optical fibre light guide to actuator

摘要

A valve with an operating piston (2) travelling inside a cylinder (1) includes a position monitoring device, using two grooves (10, 11) around the upper and lower ends of a spindle (7) extending from one end of the piston through a block (3) forming one end of the cylinder. An optical detector (12) projects through the block opposite the lower groove (11) when the piston is in its upper position and opposite the upper groove (10) at the lower position. This detector is mounted on the end of an optical fibre bundle light guide (15) directly behind, connecting it to the detector head (13) mounted on the outside. This carries an actuator (14) to initiate a logic, electronic or pneumatic operating system.