A vehicle drive includes a speed change mechanism connected to a rotary electric machine; an output member connected to the speed change mechanism and wheels; an engagement device changes a state of engagement between an input member connected to an engine and the speed change mechanism; a hydraulic pump driven by the engine or the rotary electric machine; a first pressure control device that controls pressure supplied from the pump and supplies the pressure to the speed change mechanism; a second, separate hydraulic pressure control device that controls the pressure supplied from the pump and supplies the pressure to the engagement device; and a case that houses the rotary electric machine, speed change mechanism, engagement device, and pump. At least the engagement device is housed in a space formed by the case, and the second hydraulic pressure control device is provided at a part of the case forming the space.

A failsafe multimode clutch assembly positioned in a powertrain of a rotorcraft. The clutch assembly includes a freewheeling having a driving mode in which torque applied to the input race is transferred to the output race and an overrunning mode in which torque applied to the output race is not transferred to the input race. A bypass assembly has an engaged position that couples the input and output races of the freewheeling unit. An actuator assembly uses pressurized lubricating oil to shift the bypass assembly between the engaged position and a disengaged position. A lock assembly enables and disables actuation of the bypass assembly. In the disengaged position, the overrunning mode of the freewheeling unit enables a unidirectional torque transfer mode of the clutch assembly. In the engaged position, the overrunning mode of the freewheeling unit is disabled such that the clutch assembly is configured for bidirectional torque transfer.

The present disclosure describes a hydraulic control system comprising a first pressure chamber and a second pressure chamber, each pressure chamber configured to receive a hydraulic fluid, a first movable member configured to assume a position depending on a hydraulic pressure of the hydraulic fluid in the first pressure chamber and a second movable member configured to assume a position depending on a hydraulic pressure of the hydraulic fluid in the second pressure chamber, a hydraulic command circuit configured to provide the hydraulic fluid and to control the hydraulic pressure of the hydraulic fluid in the first pressure chamber and/or the second pressure chamber, having a switchable valve in fluid communication with the first pressure chamber, wherein the switchable valve is configured to be pilotable depending on the hydraulic pressure of the hydraulic fluid in the second pressure chamber.

A fluidic control system (1) for controlling a vehicle, which includes a controller (2) and a closed fluidic circuit. The circuit includes a pump (3) for pressurizing fluid in the circuit, valve means (40, 50, 60), an actuator (4, 5, 6) and a precharge accumulator (7). The valve means (40, 50, 60) is fluidly connected to the inlet and outlet of the pump (3) and the actuator (4, 6) is fluidly connected to the valve means (40, 50, 60) for selectively receiving pressurized fluid therefrom. The precharge accumulator (7) includes a movable member (73, FIG. 2) that describes a variable volume (71) fluidly connected to the circuit between the valve means (40, 50, 60) and the inlet of the pump (3). The system (1) also includes a sensor (70) for determining the position of the movable member (73) for estimating the quantity of fluid and/or detecting an abnormal pressure variation within the circuit.

The present disclosure describes a hydraulic control system comprising a first pressure chamber and a second pressure chamber, each pressure chamber configured to receive a hydraulic fluid, a first movable member configured to assume a position depending on a hydraulic pressure of the hydraulic fluid in the first pressure chamber and a second movable member configured to assume a position depending on a hydraulic pressure of the hydraulic fluid in the second pressure chamber, a hydraulic command circuit configured to provide the hydraulic fluid and to control the hydraulic pressure of the hydraulic fluid in the first pressure chamber and/or the second pressure chamber, having a switchable valve in fluid communication with the first pressure chamber, wherein the switchable valve is configured to be pilotable depending on the hydraulic pressure of the hydraulic fluid in the second pressure chamber.

A fluidic control system (1) for controlling a vehicle, which includes a controller (2) and a closed fluidic circuit. The circuit includes a pump (3) for pressurizing fluid in the circuit, valve means (40, 50, 60), an actuator (4, 5, 6) and a precharge accumulator (7). The valve means (40, 50, 60) is fluidly connected to the inlet and outlet of the pump (3) and the actuator (4, 6) is fluidly connected to the valve means (40, 50, 60) for selectively receiving pressurized fluid therefrom. The precharge accumulator (7) includes a movable member (73, FIG. 2) that describes a variable volume (71) fluidly connected to the circuit between the valve means (40, 50, 60) and the inlet of the pump (3). The system (1) also includes a sensor (70) for determining the position of the movable member (73) for estimating the quantity of fluid and/or detecting an abnormal pressure variation within the circuit.

A method for controlling clutch pressure in an electronically controlled limited slip differential comprises receiving a target clutch pressure command indicative of a desired differential torque transfer setting. Processing the target clutch pressure command comprises estimating one of a motor current or a motor speed, calculating an integrated error of a target motor current or an integrated error of a target motor speed, calculating gains over time based on the estimated motor current or the estimated motor speed and based on the integrated error of the target motor current or the integrated error of the target motor speed, applying the calculated gains thereby forming a closed loop feedback, and calculating an oscillation. The target motor current or the target motor speed is applied to a motor connected to a clutch in the differential according to the calculated oscillation to control the clutch pressure of the differential.

A fluid control device includes: a valve body accommodating chamber having an inner space divided into a first chamber and a second chamber by a first valve body; a receiving port, which opens to the first chamber and through which a fluid from an accumulator is received in the first chamber, and a discharge port, which opens to the first chamber and through which the fluid is discharged from the first chamber; a guide path guiding the fluid from the accumulator to the second chamber such that the first valve body moves to a valve-closed position to close the discharge port; a second valve body switchable between a state of maintaining pressure of the fluid guided to the second chamber and a state of releasing the pressure; and a bias member biasing the first valve body to the valve-closed position.

A hydraulic control system includes a hydraulic pump driven by an electric motor, a solenoid valve having an output that controls the positions of a pressure regulator valve and a third, stator shift valve. The solenoid valve is a normally high, variable force solenoid valve which provides a control signal to the second and third valves. The second, pressure regulator valve is a multiple port valve which controls hydraulic fluid flow both to a transmission oil cooler (ATOC) and to an exhaust port, thereby maintaining a desired system pressure. The third, stator shift valve is also a multiple port valve and it controls fluid flow to the stator of the electric pump motor to provide cooling and to a dog clutch of the transmission to disengage it.

A hydraulic control device for an automatic transmission includes a shut-off valve arranged between a first pressure adjusting device and a respective shifting element cylinder of a plurality of shifting elements. In the first shifting position of the shut-off valve, the first pressure adjusting device is hydraulically connected to the respective shifting element cylinder through the shut-off valve. In the second shifting position of the shut-off valve, the shifting element cylinder is sealed by the shut-off valve relative to the first pressure adjusting device. The shut-off valve is an releasable check valve. The releasable check valve includes a check valve and an unblocking device. The unblocking device is actuatable by a control pressure from a second pressure adjusting device.