Abstract: The invention relates to a mechanism comprising: a cam; cylinders; pistons; two main enclosures containing feed fluid and exhaust fluid; a fluid distributor; and balancing enclosures communicating with distribution ducts included in the distributor. According to the invention, the distributor includes a face facing a reaction face secured to the cam or to the cylinder block, the balancing enclosures being constituted by chambers that open out into said end face and by a sealing device received inside the chamber and bearing against the reaction face. One application lies in providing a range of compact motors.

Abstract: This invention relates to a fluid mechanism with two cylinder capacities, comprising a distributor valve defining first and second enclosures containing supply and exhaust fluids comprising two groups of distribution conduits, and a device for selecting the cylinder capacity, constituted by a bore and a slide element for selection. According to the invention, a first and a second connection conduit connect the first and second enclosures to the bore and open out between transverse planes; distribution conduits open out in the bore between these planes; and the slide element comprises a groove contained between said planes and establishing communication between the distribution conduits and the connection conduit. One application of the invention is the production of a compact motor.

Abstract: The invention relates to a fluid engine constituted by cylinders divided into two groups, by a valve bank which comprises two enclosures connected selectively to a source of fluid and to a reservoir, and connecting each cylinder of a first group, with the said enclosures, successively, and by means for selecting the speed of the engine, which means comprise a movable member adapted to occupy two positions which, in a first position, creates a communication between the cylinder of the second group and the enclosures, successively, and in a second position, isolate said cylinders from one of the enclosures.Said engine comprises a shuttle valve which, when the movable member is in its second position, connects the cylinders of the second group to that of the two enclosures which contains the fluid under the lowest pressure.The invention finds an application in the production of a mechanically reliable reversible engine.

Abstract: A hydraulic mechanism, e.g. a pump or motor, comprises a plurality of cylinders and pistons and a piston-displacement selector which is provided with blind helical grooves for controlling connection of the cylinders to the main fluid supply.

Abstract: The invention relates to a fluid engine constituted by cylinders divided into two groups, by a valve bank which comprises two enclosures connected selectively to a source of fluid and to a reservoir, and connecting each cylinder of a first group, with the said enclosures, successively, and by means for selecting the speed of the engine, which means comprise a movable member adapted to occupy two positions which, in a first position, creates a communication between the cylinder of the second group and the enclosures, successively, and in a second position, isolate said cylinders from one of the enclosures.Said engine comprises a shuttle valve which, when the movable member is in its second position, connects the cylinders of the second group to that of the two enclosures which contains the fluid under the lowest pressure.The invention finds an application in the production of a mechanically reliable reversible engine.