END-OF-STROKE SIGNALLING DEVICE FOR A HYDRAULIC ACTUATOR

摘要

An end-of-stroke signalling device (20) for a hydraulic actuator (10) is described. The end-of-stroke signalling device (20) allows signalling the achievement of an end-of-stroke position of the main piston (14) of the hydraulic actuator and at the same time ensures that the signalling of the end-of-stroke position is not affected by pressure variations of the hydraulic fluid contained inside the chambers of the actuator cylinder. The end-of-stroke signalling device (20) comprises: an end portion (12) of the cylinder of the hydraulic actuator; - a detecting piston (21) and a balancing piston (22) which are slidingly mounted to the cylinder end portion (12) so as to be capable of sliding through the cylinder end portion (12); - a position sensor (24) mounted to the cylinder end portion (12); - a transmission element (23) operatively interposed between said detecting and balancing pistons (21, 22).