Hydraulic motor with function selector

A pressurized fluid motor comprising:

• a casing which includes two main power ducts, respectively a fluid feed duct and a fluid exhaust duct;
• a cylinder block which includes a plurality of cylinders each equipped with a piston, said cylinders being disposed radially relative to an axis and adapted to be fed with pressurized fluid;
• a reaction member adapted to cooperate with the pistons, said reaction member and the cylinder block being able to rotate relative to each other about the axis;
• an internal fluid distributor rotating with the reaction member about the rotation axis and having distribution ducts adapted to communicate with the cylinders, said distribution ducts being divided into three groups of distribution ducts;
• and
• a selector comprising a bore and a slide, the bore having a substantially cylindrical face with at least three grooves, the two main ducts and three connection ducts which are respectively connected to each of the three groups of distribution ducts being connected to said bore, the slide being mounted in the bore and having at least a first selection groove on its outside periphery, said slide being adapted to be moved between two positions in which said selection groove isolates and/or establishes communication between certain grooves of said bore,
• the motor including an additional power duct constituting a fluid feed duct or a fluid exhaust duct, wherein the bore of the selector has four annular grooves on said substantially cylindrical face and spaced from each other, said grooves comprising two "communication" grooves and two "branch" grooves, a first of the two main ducts and the first connection duct being permanently connected to the first communication groove, the second of the two main ducts and the second connection duct being permanently connected to the second communication groove, the additional duct being permanently connected to the first branch groove and the third connection duct being permanently connected to the second branch groove, and wherein the first selection groove of the slide is adapted to establish communication between the two branch grooves of the bore.