A system for locking and releasing a shifting position of a shifting element that is hydraulically actuatable by an actuating pressure is provided. The shifting element is arranged coaxially with a transmission shaft. The system includes a stop valve. The stop valve is subjectable to a control pressure that is separate from the actuating pressure of the shifting element. The stop valve is arranged radially inside the shifting element in the transmission housing.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets controls the shift actuator with actuating and opposing pulses, and interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

The present invention provides an automatic transmission capable of properly judging faults of a switching mechanism. A control part ECU of the automatic transmission TM has an actual change gear ratio calculating part 10 and a fault judging part 11. Under a condition that the control part ECU has recognized that the first brake device B1 is switched to a reverse rotation preventing state, if the actual change gear ratio is kept to be an actual change gear ratio prior to a reduce of a rotational speed of a drive source ENG when the rotational speed of the drive source ENG is reduced, then the fault judging part 11 judges that a first brake B1 has a fault.

A fault evaluation device for an automatic transmission evaluates a fault of the automatic transmission. The fault evaluation device is used for a vehicle having the automatic transmission and a control device configured to execute a learning process for correcting a target pressure for oil to be supplied to the automatic transmission such that variations in acceleration of the vehicle during shifting of the automatic transmission are small. The fault evaluation device includes a processor and a memory. The memory stores mapping data that prescribe mapping. The processor is configured to output an output variable, which is an evaluation value that indicates the presence or absence of the fault of the automatic transmission, when an input variable is input.

An electric oil pump includes a motor part having a shaft, a pump part located on a front side of the motor part and driven via the shaft, and a control part controlling the motor part. The motor part includes a rotor, a stator, and a motor housing accommodating the rotor and the stator. The pump part includes a pump rotor mounted on the shaft protruding from the motor part, and a pump housing accommodating the pump rotor. The control part includes a substrate having a surface on which a plurality of electronic components are mounted. The surface of the substrate is disposed to face the cylindrical portion of the motor housing and extends in the axial direction. The substrate has an axial length shorter than an axial length of an assembly of the motor part and the pump part and is disposed within an axial range of the assembly.

A hydraulic system for an automatic transmission of a motor vehicle. A high pressure circuit in which a pressure accumulator, at least one clutch as well as gear selectors and at least one hydraulic pump are arranged, which can be controlled by an electronic control unit. The pressure accumulator can be connected to a hydraulic positioning cylinder via at least one hydraulic path, wherein a control valve that can be controlled by the control unit is arranged upstream thereof, with which a hydraulic pressure at the hydraulic positioning cylinder can be adjusted, and which control valve can be moved between two through-flow positions in order to move a piston in opposing piston strokes via opposing piston travel paths as well as piston speeds in the hydraulic positioning cylinder.

A hydraulic system for an automatic transmission of a motor vehicle. A high pressure circuit in which a pressure accumulator, at least one clutch as well as gear selectors and at least one hydraulic pump are arranged, which can be controlled by an electronic control unit. The pressure accumulator can be connected to a hydraulic positioning cylinder via at least one hydraulic path, wherein a control valve that can be controlled by the control unit is arranged upstream thereof, with which a hydraulic pressure at the hydraulic positioning cylinder can be adjusted, and which control valve can be moved between two through-flow positions in order to move a piston in opposing piston strokes via opposing piston travel paths as well as piston speeds in the hydraulic positioning cylinder.

An actuator for actuating a parking lock and for carrying out at least one other vehicle function in a motor vehicle includes a hydraulic unit and an actuation cylinder, rigidly connected to the hydraulic unit. The hydraulic unit has a hydraulic pump or valves driven by an electric motor. The actuation cylinder is for mechanically actuating a parking lock mechanism of the parking lock. In some embodiments, the actuator has an actuator housing and the actuation cylinder has a cylinder housing that is part of the actuator housing. In some embodiments, the actuation cylinder has a piston and an actuating element, movable by means of the piston, for actuating the parking lock mechanism.

An actuator for actuating a parking lock and for carrying out at least one other vehicle function in a motor vehicle includes a hydraulic unit and an actuation cylinder, rigidly connected to the hydraulic unit. The hydraulic unit has a hydraulic pump or valves driven by an electric motor. The actuation cylinder is for mechanically actuating a parking lock mechanism of the parking lock. In some embodiments, the actuator has an actuator housing and the actuation cylinder has a cylinder housing that is part of the actuator housing. In some embodiments, the actuation cylinder has a piston and an actuating element, movable by means of the piston, for actuating the parking lock mechanism.

A method for rocking a vehicle free. The vehicle comprises a drive aggregate (2), a transmission (4), shifting elements (10), and a starting element (5). The rocking free process is carried out as a function of actuation of an accelerator pedal (11) by the driver or a torque delivered by the drive aggregate (2) as a function of the actuation of the accelerator pedal. The shifting element (10) is controlled such that reduced actuation of the accelerator pedal or reduced torque delivered by the drive aggregate (2), reduces a control pressure of the shifting element (10) of the transmission (4) down to a filling pressure or a pressure that corresponds to the filling pressure, and increased actuation of the accelerator pedal or increased torque delivered by the drive aggregate (2), increases the control pressure of the shifting element (10) and the shifting element is operated in a slipping mode.