Patent ID: 6684753
Filing Date: 2004-02-03
Classification: F04B

Abstract:
A hydraulic motor, comprising:an envelope; a differential piston capable of sliding in a reciprocating movement in the envelope, the piston having two parts of different diameters capable of moving in two corresponding chambers of the envelope; hydraulic switching means for supplying ad evacuating the respective chambers, these switching means being driven by the piston and able to adopt two stable positions relative to the piston; control means for an abrupt change in the position of the switching means relative to the piston, comprising elastic means capable of storing energy; and triggering means capable, at the end of the stroke of the piston, of releasing the energy stored by the elastic means and of causing the abrupt change in position of the switching means, these triggering means comprising thrusting means which, at the end of the piston stroke, come to bear against stops which are fixed relative to the envelope, wherein: the switching means are carried by a lantern ring with a side wall coaxial with the piston, driven by this piston but capable of adopting two different stable positions relative to the piston, the elastic means are arranged on the outside of the lantern ring and are guided internally by the side wall of the lantern ring, and the elastic means exert a force along a geometric axis of movement of the piston.