Disclosed is a hydraulic pressure supply system of a dual clutch transmission for a vehicle in which by independently configuring a low pressure supply route and a high pressure supply route, the hydraulic pressure supply system can enable a low hydraulic pressure that is generated in a hydraulic pump for a low pressure to be supplied to a gear lubrication device and a clutch cooling/lubrication device and enable a low hydraulic pressure that is generated in a hydraulic pump for a high pressure to be supplied to a gear control device and a clutch control device.

The invention relates to an electric drive system (10) for a motor vehicle, comprising an electric machine (20) with a rotor (24). A differential (38) with a differential gear (40) is provided. A gear unit (58) is provided, which is arranged in the torque flow between the rotor (24) and the differential gear (40) with respect to a torque flow emanating from the electric machines (20), and has a first input shaft (60) an output shaft (68) arranged parallel and axially offset to the first input shaft (60) and at least two gear wheels (72, 74) arranged coaxially to the first input shaft (60), namely a first gear wheel (72) and a second gear wheel (74), and two gear wheels (76, 78) arranged coaxially to the output shaft (68), namely a third gear wheel (76) and a fourth gear wheel (78).

A method for controlling a hydraulic fluid supply system of an automatic transmission of a motor vehicle includes supplying the hydraulic fluid supply system with hydraulic fluid from at least one of a hydraulic pump controlled on an engine side and a hydraulic pump controlled on a gear set side. The method also includes controlling a retaining valve of the hydraulic fluid supply system as a function of detected motor vehicle parameters in order to set an adjusted power distribution with the hydraulic pump controlled on the engine side and the hydraulic pump controlled on the gear set side.

A vehicle transmission includes a first transmission mechanism arranged to transmit mechanical driving power from an output shaft of the prime mover to a first input shaft and to put any one of a first set of gears in an engaged state to drivingly connect the first input shaft to the driving wheels; and a second transmission mechanism arranged to transmit mechanical driving power from the output shaft of the prime mover to a second input shaft and to put any one of a second set of gears in an engaged state to drivingly connect the second input shaft to the driving wheels. Controllable first and second clutch units are arranged to bring the output shaft of the prime mover and the first and the input shaft, respectively, into engagement with each other. A lubrication pump is drivingly connected to the first input shaft to lubricate the transmission and an electronic control unit is arranged to determine a lubricated state of the transmission and the operational state of the lubrication pump. When the first clutch unit is engaged to connect the output shaft of the prime mover to the first input shaft, the lubrication pump is driven by the first input shaft. When the second clutch unit is engaged to connect the output shaft of the prime mover to the second input shaft, the lubrication pump is arranged to be driven by the first input shaft by at least partly engaging the first clutch unit.

A dual clutch transmission device is disclosed. The dual clutch transmission device has a transmission device with a transmission housing, with a coupling housing positioned within the transmission housing and with a lubricant reservoir to receive a lubricant for the transmission device, which includes an oil trap ring connected at least indirectly with the transmission housing, which at least partially surrounds the coupling housing. The oil trap ring has a side facing the coupling housing which is primarily designed as an oil guide surface and which has at least one groove which is intended to guide lubricant into the lubricant reservoir. The dual clutch transmission device also has a gear set with a dry sump to lubricate the gear set.

A drive assembly for a motor vehicle has a multi-step transmission and a differential drive. The multi-step transmission comprises a rotatingly drivable driveshaft and an intermediate shaft parallel to the driveshaft, and at least one first transmission stage and a second transmission stage for transmitting torque from the driveshaft to the intermediate shaft with different transmission ratios, as well as a shift unit, wherein the intermediate shaft comprises an output gear for transmitting torque to a differential carrier of the differential drive, wherein a rotational axis of the differential carrier extends parallel to the intermediate shaft, wherein the output gear and the shift unit are arranged axially between the at least two transmission stages, and wherein the driveshaft comprises bores for supplying lubricant.

A lubrication system for a transmission includes a first tubular portion, a second tubular portion, and a hollow cylindrical member. The first tubular portion has a cavity and includes a flange at one end adjacent to a gear shaft of the transmission. The first tubular portion has a first enlarged-diameter part extending in an axial direction from a joint at which the first tubular portion is joined to the second tubular portion. The second tubular portion has a second enlarged-diameter part that extends in the axial direction from the joint and has a diameter substantially equal to a diameter of the first enlarged-diameter part. The hollow cylindrical member is disposed in the first and second tubular portions and tightly fitted in the first and second enlarged-diameter parts of the first and second tubular portions joined to each other.

A transmission oil feeder for a motor vehicle includes an input member defining a rotating shaft. An output member defines a rotating shaft. A gearing arrangement connects the input member to the output member. An oil feeder tube is disposed within a central bore of at least one of the input member or the output member. The oil feeder tube is in communication with a supply of lubricating oil. Multiple apertures are created through a wall of the oil feeder tube at a bottom of the oil feeder tube enhancing gravity flow of the lubricating oil out of the apertures. The apertures are individually prepositioned proximate to one of multiple gear sets of the gearing arrangement. Each of the apertures of the oil feeder tube deliver a portion of the supply of lubricating oil to the one of the multiple gear sets.

A transmission for a vehicle has a main shaft and a counter shaft, which are supported in a transmission case by bearings. Gears on the main shaft and gears on the counter shaft include: shifter gears which are not rotatable but axially movable relative to the shaft, and fixed gears which are rotatable but not axially movable relative to the shaft. Dog clutches are provided between the shifter gears and the fixed gears, and outer races of the bearings supporting the main and counter shafts are affixed to the transmission case. Vibration-absorbing elastic members are pressed against the outer races from axially outside and are set to have a volume of 50% or more of the volume of the outer races. With such configuration, the vibration of the bearings supporting both the main and counter shafts of the transmission is attenuated, and striking noise caused by shifting is reduced.

A control method for carrying out a gear shift in a transmission provided with a dual-clutch gearbox, so as to shift from a current gear to a following gear. The control method comprises the steps of; receiving a gear-shift command; filling with oil, always supplying the maximum possible oil flow rate, a second clutch associated with the following gear after receiving the gear-shift command; completely closing the second clutch at the maximum possible speed as soon as the oil filling ends; and completely opening a first clutch associated with the current gear A at the maximum possible speed as soon as the oil filling in the second clutch ends.