Hall sensor movement detection device.

摘要

A piston rod (6) of a piston (4) and cylinder (8) device has an axial bore (22) through which a fixed non-ferromagnetic monitoring member (24) extends, and a detection insert (26) of ferromagnetic materially extending generally axially of the monitoring member. A magnetic circuit is created through a base of the cylinder, a sidewall, the piston and the detection insert, and movement of the piston is detected by a Hall sensor (34) which detects a change of flux in the magnetic circuit.