Abstract: A hydraulic apparatus comprising a casing (1) having arranged therein a hydraulic machine (2), a shaft (4) mounted to rotate relative to the casing (1) by means of a bearing (5), a braking system (3) having a plurality of brake disks (31, 34) configured to prevent the shaft (4) rotating relative to the casing (1) in selective manner, and a control system (6, 7) for controlling said braking disks (31, 34), the hydraulic system including an irrigation system adapted to cool said brake disks (31, 34) by means of a fluid, the irrigation system including a fluid inlet (81) and a fluid outlet (82), the hydraulic system being characterized in that the fluid inlet and outlet (81, 82) of the irrigation system define a fluid flow within the casing in which the braking system (3) is downstream from the hydraulic machine (2).

Abstract: A hydraulic apparatus comprising a casing (1) having arranged therein a hydraulic machine (2), a shaft (4) mounted to rotate relative to the casing (1) by means of a bearing (5), a braking system (3) having a plurality of brake disks (31, 34) configured to prevent the shaft (4) rotating relative to the casing (1) in selective manner, and a control system (6, 7) for controlling said braking disks (31, 34), the hydraulic system including an irrigation system adapted to cool said brake disks (31, 34) by means of a fluid, the irrigation system including a fluid inlet (81) and a fluid outlet (82), the hydraulic system being characterized in that the fluid inlet and outlet (81, 82) of the irrigation system define a fluid flow within the casing in which the braking system (3) is downstream from the hydraulic machine (2).

Abstract: A hydraulic circuit having a brake pipe suitable for being connected to a pressurized fluid source or to a pressure-free reservoir, i.e. to a reservoir without excess pressure, via a proportional pressure reducer controlled by an electronic control unit (ECU). The circuit includes link solenoid-valve means suitable for connecting the proportional pressure reducer to the reservoir or, via a calibrated pressure reducer, to the pressurized fluid source.

Abstract: An open hydraulic circuit comprising a main pump (P), a hydraulic motor (M), two main ducts (10, 12) constituting a feed main duct and a discharge main duct and connected to the pump or to a reservoir (R) via a feed selector (14). The circuit further comprises a multifunction valve device comprising a multifunction selector (20) for connecting the main duct that is at the higher pressure to a pressure limiter (24) and for connecting the main duct that is at the lower pressure to booster means (16), and for interconnecting the main ducts by connecting them to the pressure limiter when the pressures in the main ducts are substantially mutually equal.

Abstract: A hydraulic circuit having a brake pipe suitable for being connected to a pressurized fluid source or to a pressure-free reservoir, i.e. to a reservoir without excess pressure, via a proportional pressure reducer controlled by an electronic control unit (ECU). The circuit includes link solenoid-valve means suitable for connecting the proportional pressure reducer to the reservoir or, via a calibrated pressure reducer, to the pressurized fluid source.

Abstract: An open hydraulic circuit comprising a main pump (P), a hydraulic motor (M), two main ducts (10, 12) constituting a feed main duct and a discharge main duct and connected to the pump or to a reservoir (R) via a feed selector (14). The circuit further comprises a multifunction valve device comprising a multifunction selector (20) for connecting the main duct that is at the higher pressure to a pressure limiter (24) and for connecting the main duct that is at the lower pressure to booster means (16), and for interconnecting the main ducts by connecting them to the pressure limiter when the pressures in the main ducts are substantially mutually equal.

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 hydrostatic transmission circuit for a vehicle having at least two displacement members (12) driven by at least one hydraulic motor (10) having a feed main duct and a discharge main duct (16, 18). Skid control means for controlling skidding of at least one displacement member comprise a skid control valve (20) and an additional valve (22) that are disposed in parallel on a main duct (16). At least the skid control valve (20) has a constriction of variable section, while the additional valve has two end positions (22A, 22B), in which its through sections are respectively at their maximum and at their minimum. Control means (UC, 26, 28) make it possible to cause said valves to move as a function of a skid situation detected by detection means (24).

Abstract: The circuit includes a main pump, a hydraulic motor, two main ducts, a selector for connecting the main ducts to the main pump or to a reservoir or for isolating them therefrom, a boost duct, and two pressure limiters disposed between the main ducts. A relief valve device that can take up a retention position and a relief position in which it connects one main duct (14, 16) to a relief enclosure can take up its relief position when, with the selector isolating the main ducts from the main pump and from the reservoir, the difference between the pressure in the main duct to which the control duct is connected and a relief pressure higher than the boost pressure changes sign.

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 circuit includes a main pump, a hydraulic motor, two main ducts, a selector for connecting the main ducts to the main pump or to a reservoir or for isolating them therefrom, a boost duct, and two pressure limiters disposed between the main ducts. A relief valve device that can take up a retention position and a relief position in which it connects one main duct (14, 16) to a relief enclosure can take up its relief position when, with the selector isolating the main ducts from the main pump and from the reservoir, the difference between the pressure in the main duct to which the control duct is connected and a relief pressure higher than the boost pressure changes sign.

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 hydrostatic transmission circuit for a vehicle having at least two displacement members (12) driven by at least one hydraulic motor (10) having a feed main duct and a discharge main duct (16, 18). Skid control means for controlling skidding of at least one displacement member comprise a skid control valve (20) and an additional valve (22) that are disposed in parallel on a main duct (16). At least the skid control valve (20) has a constriction of variable section, while the additional valve has two end positions (22A, 22B), in which its through sections are respectively at their maximum and at their minimum. Control means (UC, 26, 28) make it possible to cause said valves to move as a function of a skid situation detected by detection means (24).

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: 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.