Abstract: The present invention relates to a system for assisting the driving of a vehicle comprising at least one hydraulic machine forming a pump (19), at least one hydraulic machine forming an engine (130, 140) and an open hydraulic circuit (100) extending through a tank (13) and comprising a suction duct (11) extending from the tank (13) to an inlet of the pump (19), a supply duct (15) extending from the outlet of the pump (19) to the inlet of the engine (130, 140) and a return duct (122) extending from the outlet of the engines (130, 140) to the tank (13), characterised in that at least one of the engines (130, 140) is an engine that can disengage the clutch, and in that the system comprises an element forming a restriction (180) and creating a loss of charge over the return duct and a means (190, 192) adapted for connecting to the engine casing, the part of the return duct (122) located upstream of the element forming a restriction (180) and for applying to the engine casing, from the return duct (122), a pressur

Abstract: The present invention concerns a hydraulic system comprising a hydraulic pump (130) installed on a truck tractor (10), a hydraulic pipe (160) connected to the outlet of the pump (130) and a connector (170) positioned at the outlet of the pipe (160) and designed to be connected to a complementary socket (180) provided on a trailer (20) in order to supply a ram (110) positioned on the trailer, for example for tipping purposes, characterised by the fact that it comprises a circuit selector (210) designed to connect said socket (180) selectively either to a ram (110) or a conduit (220) supplying a drive assistance circuit and an assistance circuit return conduit (250) designed to be connected to a tank (120) positioned on the truck tractor.

Abstract: The assembly may include a cylinder block, a plurality of pistons, and a holding element, the holding element extending over all or part of the outer periphery of the cylinder block. The holding element may include a plurality of guide portions, each partially blocking a recess of the cylinder block so as to come into contact with a planar end of the crown of a piston to guide in the translation of each piston in their respective recesses. The holding element may include two indexing means cooperating with two indexing means of the cylinder block so as to hold the holding element under a traction force when positioned around the cylinder block.

Abstract: A driver circuit for driving a brake having a first orifice adapted to be connected to a pressure source, a second orifice connected to a reservoir, a third orifice receiving a braking setpoint, and a fourth orifice connected to a brake. The driver circuit includes a proportional solenoid valve connected to the first orifice; an on/off solenoid valve connected to the third orifice; and a proportional braking valve provided with an actuator and configured in such a manner as to connect a brake selectively to a pressure source or to a reservoir. The actuator is configured in such a manner as to be driven by the higher of the two pressures delivered by the proportional solenoid valve and delivered by the on/off solenoid valve.

Abstract: A hydraulic machine including: a casing rotatably mounted relative to a shaft; first brake means constrained to rotate with the casing; second brake means constrained to rotate with the shaft, and adapted to co-operate with the first brake means; a braking piston associated with return means and tending to exert a braking force; and a brake-release chamber adapted to be connected to a pressure force so as to apply a brake-release pressure selectively to the braking piston, so as to enable the first and second brake means to be separated; said hydraulic machine including a sweeping channel arranged in the shaft so as to define a leakage flow between the brake-release chamber and an internal volume of the casing.

Abstract: The hydraulic machine includes a cam and a cylinder block with pistons co-operating with cam lobes, each of which has two ramps extending between top and bottom dead center arcs. The cylinders are connected in alternation to a feed and to a discharge, in sequences separated by switchover stages including an isolation stage during which they are isolated relative to the feed and discharge main ducts. The angular position of the start or of the end of at least one first isolation stage relative to the corresponding dead center arc is different from the angular position of the start or of the end of at least one second isolation stage relative to its corresponding dead center arc, both of these dead center arcs being top dead center arcs or both of them being bottom dead center arcs.

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 method for controlling a vehicle including a main transmission and a hydraulic transmission, in which, in the absence of a setpoint on the brake, and when the hydraulic transmission is activated, a hydraulic pump of the hydraulic transmission is controlled in such a way as to establish a predetermined pressure inside a hydraulic circuit of the hydraulic transmission, and in the event of a setpoint applied to the brake, the hydraulic transmission is then controlled according to an acceleration setpoint applied to the vehicle. If the acceleration setpoint is greater than or equal to an acceleration threshold value, and the speed of travel of the vehicle is less than or equal to a speed threshold value, the hydraulic transmission is controlled in such a way as to apply a tractive force. If the acceleration setpoint is less than the first threshold value, the hydraulic transmission is disengaged.

Abstract: A method for controlling a transmission device of a vehicle. The device includes a hydraulic transmission. The displacement of the hydraulic pump is controlled so that it delivers to the n hydraulic motors a constant flow that is proportional to the speed of the wheels rotated by the drive. The displacement control of the hydraulic pump is carried out by a correction constant and a correction variable. The correction variable is determined in real time. The correction constant includes the sum of a theoretical constant and an adjusted constant. The theoretical constant is defined according to the theoretical behaviour of the hydraulic transmission. The adjusted constant is defined and corrected when the vehicle is in predetermined conditions of use, in order to reflect the real state of the vehicle.

Abstract: The invention relates to a hydraulic assistance device comprising: a hydraulic machine (30) capable of driving a wheel (W) of the craft; a variable displacement pump (10) comprising a double-acting actuator (12) defining two control chambers (12 a, 12 b) for hydraulically controlling the capacity of said pump (10); two supply lines (40a, 40 b) that connect the hydraulic machine (30) and the variable displacement pump (30) in order to form a closed circuit, characterised in that the device further comprises: two control lines (80a, 80 b), each being respectively drawn from one of the two supply lines (40a, 40 b) and being configured to respectively supply one of the two control chambers (12a, 12 b); two electrically calibratable pressure limiters (90a, 90 b) respectively disposed on the two control lines (80a, 80 b).

Abstract: The invention relates to a pressure-limiting device designed to be installed in a system comprising a first line (11) and a second line (12) that can comprise pressurised oil, as well as comprising a discharge and/or booster line (10). The limiting device is characterised in that it comprises means (131, 132, 133, 134) forming two valves, each associated with one of the two lines and adapted to open in the event of an overpressure above a pre-determined threshold on the associated line, so as to discharge the corresponding overpressure towards the discharge and/or booster line, said two valves comprising a common support stem (126) that operates in traction under the action of at least one spring defining a pressure corresponding to the pre-determined threshold. The invention also relates to a hydraulic assist system and to a vehicle comprising such a device.

Abstract: An emergency braking device including an actuator (2), a pressurizing circuit (3) supplying the actuator (2) via a control pressure and a discharge circuit (4). The discharge circuit (4) includes restrictors (13, 14) for controlling the pressure and/or flow rate of the supply fluid of the actuator (2) during a discharge of the actuator. The restrictors (13, 14) are configured to define an intermediate pressure between a low pressure level and the control pressure of the actuator (2).

Abstract: The present invention relates to a hydraulic-assistance system for motor vehicles, comprising a primary motor (M) and two hydraulic machines (140; 240, 250) connected by a hydraulic circuit such that when a first hydraulic machine (140) operates as a pump, the second hydraulic machine (240, 250) operates as a motor.

Abstract: The machine comprises distribution ducts connected to respective ones of first, second, and third enclosures (40, 42, 44), and a cylinder-capacity selector (21) suitable for being caused to take up a large cylinder capacity configuration in which the second enclosure (42) is connected to one of the main ducts (2), while the first and third enclosures (40, 44) are connected to the other main duct (1), and a small cylinder capacity configuration in which the second and third enclosures (42, 44) are connected to said one of the main ducts (2), while the first enclosure is connected to the other main duct (1). The machine further comprises a safety valve (150) having at least a first port (56) connected to said one of the main ducts (2), and a second port (58) connected to the third enclosure (44).

Abstract: The devices comprises a distributor (16) that presents distribution ducts opening out into a radial distribution face (16A), and a distributor-counterpart engaged in each other in such a manner that two main enclosures (18, 20) are provided between their opposite axially-extending faces. The device comprises a cylinder-capacity selector comprising two slides (24, 26) arranged after the other in a bore (22) of the element engaged in the other, to which are connected the main enclosures (18, 20) and at least some of the distribution ducts (30, 31). The slides are able to adopt at least three distinct configurations establishing different connections between the main ducts (18, 20) and the distribution ducts via the main enclosures, in order to be able to obtain at least three distinct operating cylinder capacities.

Abstract: A drive assembly for a motor vehicle drive shaft including an engine, a gearbox, and a shaft (50) divided into two half-shafts coupled to a differential. A hydraulic machine (10) is linked to the gear box or to the differential in order to be driven by said link. The hydraulic machine (10) forms a bearing (100) for one of the half-shafts (54).

Abstract: The present invention relates to a hydraulic device (10) with radial pistons, comprising: a shaft (12) arranged along an axis (1); a cover (13) forming a casing element, the cover and the shaft being free to rotate with respect to one another; a distribution assembly comprising: a multi-lobe cam (14); a cylinder block (15); a distributor (16) configured to exert a thrust force (P) against the cylinder block (15) along the axis (11) of the shaft; an assembly (22) of mechanical bearings comprising at least one mechanical bearing (22a) mounted in radial contact between the cover (13) and shaft (12), said assembly being configured to take up the thrust force (P) exerted by the distributor (16); and a radial contact ball bearing mounted in radial contact between the cover (13) and the shaft (12).

Abstract: The device has an internal distributor to be disposed in a casing portion (10A), and has a body (15) that has an outside axial face (15B) provided with two grooves (17, 19) respectively for feed and for discharge. The distributor has distribution ducts (23A, 23B, 23C) that open out in a distribution radial face and a cylinder capacity selector that has a slide (50) suitable for being moved in an axial bore (53) for connecting the distribution ducts to one or the other of the grooves. The device further has a control chamber (52) provided between a first end wall (15?) of the bore and the first end (50A) of the slide, and an opposing spring (55) disposed in a return chamber (52?) situated at the second end (53?) of the bore and closed, at the end closer to the distribution face (15A), by a second end wall (55?) of the distributor.

Abstract: The present invention relates to a hydrostatic transmission system comprising: at least one pump (110), at least two wheel motors (120, 122; 140, 142) supplied by the pump (110) for the mechanization of a machine, characterized by the fact that it comprises means (130) designed to offset in time a change of displacement of the motors (120, 122; 140, 142) into several groups so as to have a progressive evolution of the apparent displacement of the motors.

Abstract: The invention relates to a valve assembly (50) of a radial piston hydraulic apparatus (1). Said apparatus includes a cylinder block (4) insertable onto a shaft (2) by translation. Said assembly (50) includes: a valve (51) in contact with said cylinder block (4); a valve train cover (52); and a first (541) and second (542) chamber that are defined, respectively, by a first (511, 521) and second (512, 522) space that are located at the interface between said valve (51) and said valve train cover (52), and are intended for the pressurized fluids that enable the conversion of pressure and/or mechanical stress. Said assembly (50) includes an additional section (54) defined by a third space (541, 542) located at the interface between said valve (51) and said valve train cover (52). Said section (54) is intended for receiving a pressurized fluid such as to enable the cylinder block (4) to be inserted onto the shaft (2).