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.

A dual clutch transmission includes a pair of concentric clutches which selectively drive a pair of concentric drive shafts, pairs of gears in constant mesh, a first portion of which are associated with the first drive shaft and a first, parallel countershaft and a second portion of which are associated with the second drive shaft and a second, parallel countershaft. Synchronizer clutches disposed adjacent the gears on the countershafts selectively connect the gears to the countershafts. Both countershafts drive a single output shaft through transfer gears. The output shaft is coupled to a drive (input) pulley of a continuously variable final drive assembly which receives a chain which drives a driven (output) pulley which is coupled to and drives the cage of a differential assembly. A pair of axles are driven by the side gears of the differential and, in turn, drive the vehicle wheel.

A hydraulic system (HY) for a motor vehicle transmission (G) includes at least one pump (P), two pump output lines (P1, P2) for supplying a first pressure circuit (1) and a second pressure circuit (2), and an electromagnetically actuated, first pressure control valve (EDS1), the inlet (EDS11) of which is connected to the first pressure circuit (1) and the outlet (EDS12) of which is connected to a first control surface (PVC) of a spring-loaded shut-off valve (PV). The shut-off valve (PV) is configured for connecting, in a non-actuated condition, the second pump output line (P2) to the second pressure circuit (2) and, in the condition actuated via the first control surface (PVC), disconnecting the second pump output line (P2) from the second pressure circuit (2). A motor vehicle transmission (G) including such a hydraulic system (HY) and a drive train including such a motor vehicle transmission (G) are also provided.

A clutch-side transmission circuit transmits, from a clutch pedal, a restoring action of the depressed clutch pedal. A switching device connects a first clutch-side hydraulic circuit to the pedal-side hydraulic circuit when a shift lever SL is tilted forwards and connects a second clutch-side hydraulic circuit to the pedal-side hydraulic circuit when the shift lever SL is tilted rearwards. A first clutch is engaged in response to the restoring action of the clutch pedal being transmitted from the first clutch-side transmission circuit. A second clutch is engaged in response to the restoring action of the clutch pedal being transmitted from the second clutch-side transmission circuit.

A method controls a power transmission device including a continuously variable transmission, an electric oil pump provided in a first oil passage connecting primary and secondary pulley oil chambers of the continuously variable transmission, and a switching valve provided at a branch point between the first oil passage and a second oil passage that branches from the first oil passage between the electric oil pump and the primary pulley oil chamber and that is connected to an oil reservoir. A third oil passage branches from the first oil passage between the electric oil pump and the secondary pulley oil chamber. The method makes a magnitude of a hydraulic pressure difference between the third oil passage and the first oil passage one the side of the primary pulley oil chamber smaller than a prescribed threshold value when the switching valve switches between a first position and a second position.

A hydraulic system for a hybrid module which is located between an engine and a transmission includes a parallel arrangement of a mechanical pump and an electric pump. Each pump is constructed and arranged to deliver oil to other portions of the hydraulic system depending on the operational mode. Three operational modes are described including an electric mode, a transition mode, and a cruise mode. Various monitoring and control features are incorporated into the hydraulic system.

Control system for a continuously variable transmission with a first and a second pair of conical sheaves each with adjustable running radius, in which of each pair at least one sheave (14a, 14b) is coupled to a first and a second hydraulic actuator (20a, 20b) respectively which sets the axial sheave position in dependence of the amount of hydraulic medium supplied thereto, in which the actuators are connected with means to supply and discharge thereto/therefrom respectively, hydraulic medium, and one actuator is connected to a source of hydraulic pressure medium, and in which furthermore the first and second actuator respectively is connected with a first and second control chamber (60, 124) respectively, filled with hydraulic medium and having a variable control volume, in such a way that an increase of the first control volume is coupled to a decrease of the second control volume, and vice versa.

A hydraulic control system for a transmission includes a source of pressurized hydraulic fluid that communicates with an electronic transmission range selection (ETRS) subsystem or manual valve and a clutch actuation subsystem.

A parking lock apparatus includes an engaging mechanism, a slider, a hydraulic circuit, and a processor. The engaging mechanism is to prevent a rotation of a rotating body when the engaging mechanism is in a mechanical engagement state. The slider is to switch a state of the engaging mechanism between the mechanical engagement state and a mechanical disengagement state in accordance with a position of the slider. The hydraulic circuit is to change the position of the slider. The processor is configured to increase line pressure in the hydraulic circuit when the engaging mechanism is in the mechanical engagement state.

A hydraulic system of vehicle transmission device is provided. A heat exchanger configured downstream is used to cool working oil discharged from a torque converter, and the working oil is supplied, as lubricating oil, to a lubricating system hydraulic circuit. On the other hand, excess oil flowing out of a regulator valve for regulating line pressure returns to an input side of an oil pump through a recycle oil path. A bypass oil path is disposed in a manner of branching from the recycle oil path and connecting to an input side of the heat exchanger. A control mechanism is disposed, and when hydraulic pressure at the side of the recycle oil path is higher than that at the side of the heat exchanger, the bypass oil path is opened to guide oil at the side of the recycle oil path to the input side of the heat exchanger.