Hydraulic working cylinder with integrated stroke-displacement measuring system, in particular for underground support and extracting systems and the like

摘要

The invention is directed towards a hydraulic working cylinder which is equipped with a built-in stroke-displacement measuring system. The latter consists of a sensor bar which is supported on the base of the working cylinder and engages in an axial bore of the piston rod. Arranged at the head of the sensor bar is a measuring head which is formed by a rotary potentiometer and a small rotor which sits on the drive shaft of the rotary potentiometer and, with a sliding block or the like, engages in a helical groove on the inner wall of the axial bore of the piston rod. In this way, the stroke movement of the piston of the working cylinder is converted into a rotary movement of the rotor and thus into a rotary movement of the rotary potentiometer.