Abstract: A valve including a valve body having an inlet port and an outlet port, a valve stem, a valve seat, an opening control chamber for the valve stem, which chamber, by being fed with fluid, urges the valve stem to move towards the open position of the valve, a return spring of opposing effect, and a piston suitable for sliding in the body so as to urge contact to be established between the valve stem and the seat. The valve seat is formed on the piston, which piston is provided with a bore in which the valve stem is in its closure movement, the fluid flows out via a constriction from a damping chamber.

Abstract: A valve including a valve body having an inlet port and an outlet port, a valve stem, a valve seat, an opening control chamber for the valve stem, which chamber, by being fed with fluid, urges the valve stem to move towards the open position of the valve, a return spring of opposing effect, and a piston suitable for sliding in the body so as to urge contact to be established between the valve stem and the seat. The valve seat is formed on the piston, which piston is provided with a bore in which the valve stem is in its closure movement, the fluid flows out via a constriction from a damping chamber.

Abstract: The device comprises a replenishing valve (24) having an opening control chamber suitable for being connected to a main duct (12, 14) of the circuit, and a closing control chamber, the pressure in said chambers making it possible to cause the moving member of the replenishing valve to move so as either to connect or not to connect the main duct to which said valve is connected to a pressure-free reservoir. The device further comprises a control valve (46) which is controlled as a function of at least one control parameter representing a state of the circuit other than pressure in said main duct to which said replenishing valve (24) is connected, in order to connect the closing control chamber to the pressure-free reservoir or in order to isolate said chamber from said reservoir.

Abstract: The device comprises a replenishing valve (24) having an opening control chamber suitable for being connected to a main duct (12, 14) of the circuit, and a closing control chamber, the pressure in said chambers making it possible to cause the moving member of the replenishing valve to move so as either to connect or not to connect the main duct to which said valve is connected to a pressure-free reservoir. The device further comprises a control valve (46) which is controlled as a function of at least one control parameter representing a state of the circuit other than pressure in said main duct to which said replenishing valve (24) is connected, in order to connect the closing control chamber to the pressure-free reservoir or in order to isolate said chamber from said reservoir.

Abstract: A replenishing device for a closed circuit comprising at least one hydraulic motor and at least two main pipes which are connected to the pump to provide respectively the feed and the discharge for the motor. The device comprises a replenishing selector suitable for putting the main pipe that is at the lower pressure in communication with a valve which itself communicates with an atmospheric pressure reservoir. The replenishing selector and the valve are united in the same replenishing valve unit having an inlet suitable for being connected to the main pipe that is at the lower pressure, and an outlet which communicates continuously with the atmospheric pressure reservoir. The valve is suitable for causing the inlet to communicate with the outlet when the pressure in said main pipe reaches a given pressure threshold.

Abstract: The tapping circuit forms part of a main fluid circuit which comprises a hydraulic motor having a preferred operating direction and at least two main pipes suitable for communicating with the cylinder block of the motor and constituting respectively, in said preferred operating direction, a feed main pipe and a discharge main pipe. The tapping circuit comprises a single tapping and removal valve connected continuously via a tapping pipe to that one of said main pipes which, in the preferred direction, serves for discharge purposes. This valve serves to replenish the fluid so as to cool it and/or to flush the internal space of the casing of the motor.

Abstract: A hydraulic circuit for the hydrostatic transmission of a vehicle, said hydraulic circuit comprising at least one hydraulic motor, two main ducts, a parking brake having brake means, brake release control means suitable for feeding the brake release chamber from a first brake release fluid source, and means for connecting said chamber to a unpressurized reservoir. The circuit has a single short-circuit and selection valve having two main ports connected to respective ones of the two main ducts, and two selection ports connected respectively to the brake release chamber and to the brake release duct, and control means for controlling said valve, which control means are suitable for causing the valve to take up a first configuration in which the main ports are mutually isolated while the selection ports are interconnected, and for causing it to take up a second configuration in which the main ports are interconnected while the selection ports are mutually isolated.

Abstract: A hydraulic circuit for the hydrostatic transmission of a vehicle, said hydraulic circuit comprising at least one hydraulic motor, two main ducts, a parking brake having brake means, brake release control means suitable for feeding the brake release chamber from a first brake release fluid source, and means for connecting said chamber to a unpressurized reservoir. The circuit has a single short-circuit and selection valve having two main ports connected to respective ones of the two main ducts, and two selection ports connected respectively to the brake release chamber and to the brake release duct, and control means for controlling said valve, which control means are suitable for causing the valve to take up a first configuration in which the main ports are mutually isolated while the selection ports are interconnected, and for causing it to take up a second configuration in which the main ports are interconnected while the selection ports are mutually isolated.

Abstract: A replenishing device for a closed circuit comprising at least one hydraulic motor and at least two main pipes which are connected to the pump to provide respectively the feed and the discharge for the motor. The device comprises a replenishing selector suitable for putting the main pipe that is at the lower pressure in communication with a valve which itself communicates with a pressure-free reservoir. The replenishing selector and the valve are united in the same replenishing valve unit having an inlet suitable for being connected to the main pipe that is at the lower pressure, and an outlet which communicates continuously with the pressure-free reservoir. The valve is suitable for causing the inlet to communicate with the outlet when the pressure in said main pipe reaches a given pressure threshold.

Abstract: The tapping circuit forms part of a main fluid circuit which comprises a hydraulic motor having a preferred operating direction and at least two main pipes suitable for communicating with the cylinder block of the motor and constituting respectively, in said preferred operating direction, a feed main pipe and a discharge main pipe. The tapping circuit comprises a single tapping and removal valve connected continuously via a tapping pipe to that one of said main pipes which, in the preferred direction, serves for discharge purposes. This valve serves to replenish the fluid so as to cool it and/or to flush the internal space of the casing of the motor.

Abstract: This invention relates to a valve device for at least one hydraulic motor adapted to drive a high inertia mass. The device comprises two principal conduits, respectively intended to be connected to the two principal ducts (supply or exhaust) of the motor. It comprises a communication conduit for placing said principal conduits in situation of communication when the fluid pressures in these conduits are substantially equal and for placing said principal conduits in a situation of isolation in which they are isolated from one another when the fluid pressures in these two conduits are different. The device further comprises delaying means adapted to limit the speed of passage between the situation of communication and the situation of isolation. The communication conduit may include a calibrated restriction. Similarly, the delaying means may include calibrated restrictions.

Abstract: This invention relates to a hydraulic fluid circuit comprising a reversible hydraulic motor, a braking device, two principal conduits respectively connected to the two principal supply and exhaust ports of the motor, a principal selector adapted to occupy a position of rest and two active positions in order to select the circulation of the fluid between the principal ports of the motor and the principal conduits to which they are connected. The circuit also comprises an intermediate system of selection capable of occupying a first configuration in which the principal selector is maintained in its position of rest and a second configuration in which the principal selector is allowed to leave its position of rest. The control means of the intermediate system of selection are connected to the braking device so that this intermediate system can pass from its first to its second configuration only when the brake is de-activated.