Pipe bending machine

Claim 1

A HYDRAULIC DEVICE FOR BENDING PIPES AND LIKE ELONGATED WORK PIECES COMPRISING, IN COMBINATION: (A) A SUPPORT; (B) A BENDING MANDREL FIXEDLY MOUNTED ON SAID SUPPORT; (C) A FIRST PRESSURE-FLUID OPERATED MOTOR INCLUDING A CYLINDER MEMBER HAVING AN AXIS AND A PISTON MEMBER AXIALLY SLIDABLE IN SAID CYLINDER MEMBER, SAID CYLINDER MEMBER AND SAID PISTON MEMBER CONSTITUTING A FIRST PAIR OF MEMBERS, ONE OF SAID MEMBERS OF SAID PAIR BEING FASTENED TO SAID SUPPORT FOR AXIAL MOVEMENT OF THE OTHER MEMBER OF SAID PAIR; (D) A SECOND PRESSURE-FLUID OPERATED MOTOR INCLUDING A CYLINDER MEMBER HAVING AN AXIS AND A PISTON MEMBER AXIALLY SLIDABLE IN THE CYLINDER MEMBER OF SAID SECOND MOTOR, SAID PISTON MEMBER AND CYLINDER MEMBER OF SAID SECOND MOTOR CONSTITUTING A SECOND PAIR OF MEMBERS AXIALLY ALIGNED WITH SAID FIRST PAIR, ONE MEMBER OF SAID SECOND PAIR BEING SECURED TO SAID OTHER MEMBER OF SAID FIRST PAIR FOR AXIAL MOVEMENT OF THE OTHER MEMBER OF SAID SECOND PAIR TOWARD AND AWAY FROM SAID MANDREL; (E) AN ELONGATED BENDING RAIL HAVING TWO END PORTIONS, ONE OF SAID END PORTIONS BEING SECURED TO SAID OTHER MEMBER OF ONE OF SAID PAIRS, AND THE OTHER END PORTION ENGAGING THE OTHER MEMBER OF THE OTHER ONE OF SAID PAIRS; AND (F) VALVE MEANS FOR SEPARATELY CONTROLLING FLOW OF A PRESSURE FLUID TO AND FROM EACH OF SAID CYLINDER MEMBERS.