Patent ID: 7207260

Claim:
A hydraulic motor, comprising: a body closed at its top by a removable cover; an exchangeable cylindrical liner located in the body interior and defining a cylindrical housing for the piston, the liner changed quickly by removing the cover and extracting the liner in a translational movement, and fitting a new liner; a piston able to slide in a reciprocating movement in the cylindrical housing, a chamber being formed on each side of the piston; hydraulic switching means for feeding and evacuating the respective chambers, these switching means being able to adopt two stable positions; control means having elastic means for abruptly bringing about changes in the position of the switching means; and triggering means able, at the end of the stroke of the piston, to bring about the change in position of the switching means, wherein the piston is a simple piston, having a closed cross section; and the switching means are arranged in the body of the machine, radially on the outside of the cylindrical housing in which the piston slides.