Position monitoring device for the piston of a motor vehicle braking system has a rare earth magnet of none-circular shape mounted in an axial bored hole in the piston

摘要

Device for monitoring the position and or movement of a piston, comprises a main cylinder (1) with integrated position transmitter for monitoring the position of a piston (2, 3) moving within a housing (6). A magnetic field sensor is fixed on the housing. The signal transmitter is a rare-earth magnet (35) of none-circular shape whose average diameter is much less than that of the piston. The piston has a bored hole that is parallel to the housing axis (X) and in which the magnet is held.