Abstract: A method for driving a parking brake of a vehicle (V) wherein: for a setpoint between 0 and C1, the control pressure (200) is zero, and the supplementary pressure (100) is non—zero constant; for a setpoint between C1 and C3, the control pressure is proportional to the setpoint, for a setpoint between C2 and Cmax, the supplementary pressure is zero; said values being such that 0<C1<C2<Cmax, and 0<C1<C3<Cmax.

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 method for driving a parking brake of a vehicle (V) wherein: for a setpoint between 0 and C1, the control pressure (200) is zero, and the supplementary pressure (100) is nonzero constant; for a setpoint between C1 and C3, the control pressure is proportional to the setpoint, for a setpoint between C2 and Cmax, the supplementary pressure is zero; said values being such that 0<C1<C2<Cmax, and 0<C1<C3<Cmax.

Abstract: A method for driving a braking circuit for a vehicle equipped with a coupling is disclosed. The vehicle incudes a hydraulic supply circuit and a hydraulic control circuit equipped with a driving device. The coupling includes a hydraulic braking circuit linked to the hydraulic supply circuit and to the hydraulic control circuit and includes a hydraulic accumulator. When the vehicle is stopped and the pressure inside the hydraulic accumulator is less than or equal to a threshold pressure value, the driving deice increases the pressure of the hydraulic accumulator via the hydraulic control circuit.

Abstract: The present invention concerns a hydraulic pressure amplifier device comprising a casing (10) having two chambers (12, 14) of different cross-sections which house a staged piston (20) comprising two piston sections (22, 24) with cross-sections respectively el matching the chambers (12, 14), and means (30) for controlling the movement of the piston (20), characterised by the fact that the control means (30) are formed of an electronic control driven by means for estimating the ends-of-stroke of the piston (20) without an end-of-stroke sensor or mechanical stop.

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: Hydraulic transmission apparatus (20) including a pump (24) having a variable cylinder capacity and feeding one or more hydraulic motors (26A, 26B), and a control unit (50). In the apparatus, the feed and discharge orifices of the motors are arranged in such a manner that, when the pressures at said orifices are equal, the outlet torque from the motors is zero. To make the apparatus inactive, without physically bypassing the motors, the control unit is suitable for operating the apparatus in a “torque-free” mode by regulating the cylinder capacity of the pump in such a manner that the pressures at said feed and discharge orifices remain substantially equal.

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: The invention relates to an emergency braking device comprising an actuator (2), a pressurizing circuit (3) supplying the actuator (2) via a control pressure and a discharge circuit (4), characterized in that the discharge circuit (4) comprises means (13, 14) for controlling the pressure and/or flow rate of the supply fluid of the actuator (2) during a discharge of the actuator, these control means (13, 14) being 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: A hydraulic transmission apparatus having at least one declutchable hydraulic motor having radial pistons and connected via two motor ducts, and a casing duct connected to the inside of the casing. The apparatus further has clutching means that, in order to perform the clutching of the motor, are suitable for bringing a first one of the motor ducts to a “clutching” first pressure that is higher than the pressure in the casing while also making it possible to remove fluid via the casing duct. Disposed on the casing duct, the apparatus further has means for limiting the flow of fluid in said casing duct, in a manner such as to cause the pressure inside the casing to increase during the clutching operation. This apparatus enables clutching to take place gently.

Abstract: The present disclosure is directed to a hydrostatic transmission apparatus including a pump, a first motor, and a second motor having two elementary motors. Each of the motors having first and second enclosures for feed/discharge. In work mode and in road mode, the second enclosure of the first elementary motor of the second motor and the first enclosure of the first motor are connected together in series, the second enclosure of the first motor being connected to the second port of the pump, and the second enclosure of the second elementary motor of the second motor is connected to the second port of the pump. In work mode, the first enclosure of each of the two elementary motors of the third motor is connected to the first port of the pump.

Abstract: Hydraulic transmission apparatus (20) including a pump (24) having a variable cylinder capacity and feeding one or more hydraulic motors (26A, 26B), and a control unit (50). In the apparatus, the feed and discharge orifices of the motors are arranged in such a manner that, when the pressures at said orifices are equal, the outlet torque from the motors is zero. To make the apparatus inactive, without physically bypassing the motors, the control unit is suitable for operating the apparatus in a “torque-free” mode by regulating the cylinder capacity of the pump in such a manner that the pressures at said feed and discharge orifices remain substantially equal.

Abstract: A hydraulic circuit. The circuit includes a high pressure line and a low pressure line, the pressure in the high pressure line being greater than the pressure in the low pressure line, a hydraulic machine having two ports designed to be connected to the high pressure and low pressure lines, a first of the ports being a hydraulic fluid intake port and the second of the ports being a hydraulic fluid discharge port The circuit includes a sequential connector designed to connect the ports of the hydraulic machine to the high and low pressure lines.

Abstract: Hydraulic transmission apparatus including a pressurized fluid source and at least one hydraulic motor fed by said pressurized fluid source. The motor has two motor ducts for feed/discharge, and one casing duct. The motor can be operated in assisted mode, in which it generates torque or in unassisted mode in which it does not generate any torque and its pistons are maintained in the retracted position under the effect of the pressure in the casing duct. The apparatus further includes an accumulator suitable for feeding: the motor ducts during a stage of passing from the unassisted mode to the assisted mode in order to facilitate deployment of the pistons; and the casing duct during a stage of passing from the assisted mode to the unassisted mode in order to facilitate retraction of the pistons. This apparatus thus enables the motor to be positively clutched/declutched quickly.

Abstract: The present disclosure is directed to a hydrostatic transmission apparatus including a pump, a first motor, and a second motor having two elementary motors, each of them and the first motor having feed/discharge first and second enclosures. In work mode and in road mode the second enclosure of the first elementary motor of the second motor and the first enclosure of the first motor are connected together in series, the second enclosure of the first motor being connected to the second port of the pump and the second enclosure of the second elementary motor of the second motor is connected to the second port of the pump. In work mode, the first enclosure of each of the two elementary motors of the third motor is connected to the first port of the pump.

Abstract: A hydraulic transmission system for a vehicle is provided. The system includes a main pump serving to feed with fluid at least one hydraulic motor for driving a vehicle mover member; an auxiliary pump, the main pump and the auxiliary pump being suitable for being actuated jointly; and a “bypass” connection between a delivery orifice of the auxiliary pump and an unpressurized reservoir. In addition, a first constriction is arranged on the bypass connection, and configured to maintain a pump protection pressure in a pump protection portion of the bypass connection. This pressure is applied to the main orifices of the main pump when said pump is actuated but is not delivering, thereby ensuring that the pump is protected.

Abstract: A hydrostatic transmission apparatus for a vehicle having at least two wheels, the second wheel being steerable, may include a main hydraulic pump, two hydraulic motors driving respective ones of the wheels, detection means for detecting that the second wheel is turned by being steered, a first synchronization duct between the first and second motors, and re-feed means for re-feeding the first synchronization duct, and suitable for acting, while the second motor is being fed by the first motor via the first synchronization duct, and when the second wheel is turned by being steered, to inject fluid into the first synchronization duct while limiting the pressure in said synchronization duct to a pressure less than a re-feed pressure that is significantly less than the high pressure of the pump.

Abstract: Hydrostatic transmission apparatus for a vehicle having a front group of drive members and a rear group of drive members, a pump, a front motor and a rear motor contributing to driving respective ones of the front and rear groups of drive members; a first one of the motors and a second one of the motors connected to the first motor via a series duct also being connected to the main orifices of the pump, thereby constituting a closed transmission circuit; at least one pressure-limiting valve being interposed between the series duct and a low-pressure circuit, and being suitable for connecting the series duct to the low-pressure circuit while being controlled as a function of the high pressure of the pump. The pressure in the series duct is thus effectively limited to a pressure representative of the pressure necessary for driving the vehicle.