Hydraulic device for the automatic actuation of a piston

Claim 1

A HYDRAULIC ACTUATING DEVICE COMPRISING, IN COMBINATION, A SINGLE CYLINDER MEMBER FORMED WITH AN OPERATING CHAMBER AND AN INLET CHAMBER OF A DIAMETER SMALLER THAN THAT OF SAID OPERATING CHAMBER; A DIFFERENTIAL COMMUNICATING WITH SAID INLET CHAMBER; A DIFFERENTIAL PISTON MEMBER LOCATED IN SAID CHAMBERS AXIALLY SLIDABLE RELATIVE TO SAID CYLINDER MEMBER AND HAVING A PAIR OF OPPOSITELY DIRECTED ACTING FACES, ONE OF SAID FACES BEING WIDER AND LOCATED IN SAID OPERATING CHAMBER AND THE OTHER OF SAID FACES BEING NARROWER AND BOUNDING SAID INLET CHAMBER SO THAT ANY FLUID PRESSURE IN SAID INLET CHAMBER URGES SAID DIFFERENTIAL PISTON MEMBER IN A FIRST DIRECTION RELATIVES TO SAID CYLINDER MEMBER TOWARD A FIRST END POSITION AND ANY FLUID PRESSURE IN SAID OPERATING CHAMBER URGES SAID PISTON MEMBER IN A SECOND DIRECTION RELATIVE TO SAID CYLINDER MEMBER TOWARD A SECOND END POSITION; PASSAGE MEANS IN SAID PISTON MEMBER CONNECTING SAID OPERATING CHAMBER WITH THE ATMOSPHERE; VALVE MEANS IN SAID PASSAGE MEANS MOVABLE BETWEEN A CLOSED AND AND OPEN POSITION; ACTUATING MEANS FOR SAID VALVE MEANS AND COOPERATING WITHIN SAID CYLINDER MEMBER FOR AUTOMATICALLY MOVING SAID VALVE MEANS TO SAID OPEN POSITION WHEN SAID PISTON MEMBER HAS REACHED SAID SECOND END POSITION, MAINTAINING SAID VALVE MEANS IN OPEN POSITION WHILE SAID PISTON MEMBER IS MOVING IN SAID FIRST DIRECTION FROM SAID SECOND TOWARD SAID FIRST END POSITION AND CLOSING SAID VALVE MEANS WHEN SAID PISTON MEMBER REACHES SAID FIRST END POSITION, SAID VALVE MEANS REMAINING IN SAID CLOSED POSITION WHILE SAID PISTON MEMBER IS MOVING BACK IN SAID SECOND DIRECTION; A PASSAGE IN SAID PISTON MEMBER RESTRICTED RELATIVE TO SAID PASSAGE MEANS AND PERMANENTLY CONNECTING SAID INLET CHAMBER WITH SAID OPERATING CHAMBER; AND FIRST AND SECOND OUTLET PORT NOZZLE MEANS IN SAID CYLINDER MEMBER CONSTUCTED AND ARRANGED AND COOPERATING WITH SAID PISTON MEMBER IN SUCH A MANNER THAT SAID FIRST OUTLET PORT NOZZLE MEANS ARE OPEN WHEN SAID PISTON MEMBER MOVES IN SAID FIRST DIRECTION AND CLOSED WHEN IT MOVES IN SAID SECOND DIRECTION, AND VICE VERSA, SAID SECOND OUTLET PORT NOZZLE MEANS ARE OPEN WHEN SAID PISTON MEMBER MOVES IN SAID SECOND DIRECTION AND ARE CLOSED WHEN SAID PISTON MEMBER MOVES IN SAID FIRST DIRECTION.