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.

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 pressure control valve, in particular for an automatic transmission in a motor vehicle, including a housing and including a control piston situated in the housing, the control piston being actuatable by an armature situated in a magnet chamber of a pole tube, the magnet chamber being hydraulically connected to a compensating chamber provided in the housing, which is delimited, in particular by a lateral surface of a solenoid coil and the housing.

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.

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.

When the vehicle speed increases and reaches a predetermined switching threshold, the controller reduces the displacement of the first travel motor and controls the flow rate control device to offset a flow rate excess in the hydraulic circuit in accordance with the reduction in the displacement of the first travel motor. After the vehicle speed has reached the switching threshold, the controller executes switching control to switch the clutch from an engaged state to a disengaged state.

When the vehicle speed increases and reaches a predetermined switching threshold, the controller reduces the displacement of the first travel motor and controls the flow rate control device to offset a flow rate excess in the hydraulic circuit in accordance with the reduction in the displacement of the first travel motor. After the vehicle speed has reached the switching threshold, the controller executes switching control to switch the clutch from an engaged state to a disengaged state.

A gear change control system includes: a shift operation member configured to receive a shift range operation; a clutch configured to transmit a torque of an input shaft to an output shaft; a clutch actuator configured to control engagement of the clutch by using a working fluid; a manual valve configured to switch a supply destination of the working fluid to the clutch actuator in accordance with a decided shift range; a shift actuator configured to move the manual valve on the basis of a shift range changing operation of the shift operation member; and an oil pressure control actuator configured to reduce an oil pressure of the working fluid to a target oil pressure after the shift range changing operation received by the shift operation member is started and before the shift actuator moves the manual valve toward a shift range changing destination.

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.

A hydraulic circuit for a transmission includes a friction element that engages or disengages an operating element of the transmission, a pump that pumps oil to form preliminary pressure that allows the friction element to be maintained in a standby state in which the friction element is ready to operate, and a direct control valve that receives the oil that has passed through the pump and adjusts the preliminary pressure to form operating pressure that allows the friction element to operate, when operating the friction element. The friction element includes a hydraulic chamber into which the oil is introduced, a first supply hole through which the oil that has passed through the pump is supplied to the hydraulic chamber, and a second supply hole through which the oil that has passed through the direct control valve is supplied to the hydraulic chamber.