Audi Ag

Florian Bartl

Tobias Kramer

Stefan Rugies

A dual-clutch transmission includes a hydraulic system for actuating hydraulic cylinders of the clutches and the shifting elements. The hydraulic system has a pressure accumulator providing an accumulated pressure in the hydraulic system, and control valves actuatable by a control unit and respectively arranged in pressure lines routed to the hydraulic cylinders of the clutches to adjust the hydraulic pressure applied to the clutches. Pressure sensors associated with the control unit detect the hydraulic pressure. The control unit activates a pressure reduction mode when detecting a long vehicle downtime, and the accumulated pressure can be reduced in the pressure reduction mode, in which the control unit continuously opens the control valve associated with one clutch. Additionally, the pressure sensor associated with the first clutch together with the control unit is integrated into a control circuit in which the first pressure sensor assumes the detection of the actual accumulated pressure value.

Hydraulic system for a dual-clutch transmission

A device for generating an impulse acting on a vehicle in a transverse direction of the vehicle, resulting from energy released in an offset impact of the vehicle against an obstacle, includes a compression-resistant beam extending in the transverse direction, a support member for attaching the beam in a rest position to a subframe or a body structure of the vehicle, an activator for moving the beam substantially in the transverse direction in the event of an accident, and a coupling device which cooperates is operatively connected, at least during movement of the beam in the transverse direction, with a drive unit or aggregate and deflects the drive unit relative to the vehicle's body in the transverse direction at least in the region of the operative connection.

Device for generating an impulse acting on a vehicle in a transverse direction of the vehicle

In a method for operating a transmission device, a pressure test is carried out when switching from a standby mode to a power saving mode. When executing the pressure test the gear selector valves of the gear selectors of the transmission device are activated to assume their neutral position, and a shifting valve is activated to assume an operating position in which a flow connection between a common feed line for the gear selectors and a pressure source is cut. Subsequently, the gear selector valve of at least one of the gear selectors is activated to assume a shift position, and a position of the gear selector piston of the at least one gear selector is determined over a specific time period. The presence of a malfunction of the shifting valve is recognized when the position of the gear selector piston changes during the specific time period.

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Bergheim, Germany

Florian Bartl