A vehicle drive includes a speed change mechanism connected to a rotary electric machine; an output member connected to the speed change mechanism and wheels; an engagement device changes a state of engagement between an input member connected to an engine and the speed change mechanism; a hydraulic pump driven by the engine or the rotary electric machine; a first pressure control device that controls pressure supplied from the pump and supplies the pressure to the speed change mechanism; a second, separate hydraulic pressure control device that controls the pressure supplied from the pump and supplies the pressure to the engagement device; and a case that houses the rotary electric machine, speed change mechanism, engagement device, and pump. At least the engagement device is housed in a space formed by the case, and the second hydraulic pressure control device is provided at a part of the case forming the space.

A method for determining an output torque in a drive system capable of being power shifted in a vehicle includes providing the drive system having a drive unit for transmitting the drive torque, a dual clutch having a first clutch and a second clutch, and a power shift transmission. The power shift transmission has a first gear with a first gear ratio and a second gear with a second gear ratio. The method also includes measuring a first torque transmitted by the first clutch, calculating a distribution of the drive torque to the first clutch and the second clutch using the first torque, and determining the output torque from the distribution of the drive torque.

A line pressure control method for a double clutch transmission (DCT) includes estimating a line pressure, which decreases with stoppage of an electric oil pump, based on a linear regression model using state variables of the DCT that are related to a line pressure change, and driving the electric oil pump when the line pressure estimated based on the linear regression model reaches a predetermined lower limit.

An apparatus to be applied to a vehicle including a transmission configured to execute a gear shifting operation for changing a gear ratio by engaging or disengaging friction engagement elements having friction members pushed by a piston that moves through hydraulic pressure supply to an oil chamber, the apparatus including: a memory storing mapping data for defining mapping, the mapping including a pressure variable and a period variable as input variables, the mapping including a stroke amount as an output variable, the pressure variable indicating a waiting pressure, the period variable indicating a waiting period; and a processor configured to: acquire values of the input variables, and calculate a value of the output variable by inputting, to the mapping, the acquired values of the input variables.

An apparatus of controlling a twin clutch includes: a twin clutch that selectively blocks power supplied from a drive motor to a pair of drive wheels of a vehicle; and a clutch controller that is configured to control the twin clutch by determining target torques applied to respective clutches included in the twin clutch, based on the straight-line driving state detected by the driving information detection unit, determining a correction error based on a difference between actual torques applied to the respective clutches included in the twin clutch when a preliminary activation signal, which is determined based on the target torques, is turned on and a main activation signal, which is determined based on the actual torques applied to the respective clutches, is turned on, determining a balancing control compensation amount based on the correction error, and determining a final control amounts applied to the respective clutches based on the balancing control compensation amount.

An intelligent clutch lubrication system includes a first dynamically-lubricated clutch pack, a supply pump, a first lubricant control (LC) valve, and a lubricant flow circuit having a clutch lubrication loop in which the first clutch pack is positioned. When active, the supply pump urges lubricant flow about the lubricant flow circuit and through the clutch lubrication loop. The first LC valve is positioned in the clutch lubrication loop at a location upstream of the first clutch pack, while a controller architecture is operably coupled to the first LC valve. the controller architecture is configured to control the first LC valve to temporarily boost lubricant flow to the first DL clutch pack when moving into an engaged position during operation of the intelligent clutch lubrication system.

The invention relates to a hydraulic circuit (1) of a torque transmission device, wherein at least two, in particular closed in a non-actuated state (normally closed), clutches (2, 3) of the torque transmission device can be element (12, 13) of the hydraulic circuit, wherein in a clutch opening state, every clutch valve element (12, 13) is connected to a high-pressure line (30) that is applied with the pressure of a high-pressure hydraulic accumulator (31) and/or generator (32), by means of a pressurisation line (22, 23) for the deflection of the clutch (2, 3), and in a closing state, same is connected to a low-pressure tank (40) by means of a tank line (42, 43, 44, 45, 46, 47, 48, 49) for releasing a deflection pressure, and wherein the tank lines (42, 43, 44, 45, 46, 47, 48, 49) of the clutch valve elements (12, 33) are guided to a safety valve (50), in particular by means of a common collection tank line (41), which safety valve can be switched in such a way that the tank lines (42, 43, 44, 45, 46, 47, 48, 49) can be applied with the pressure of the high-pressure line (30).

An adaptive control device is provided for a vehicle starting clutch. The adaptive control device includes a reverse brake as the starting clutch, and a clutch adaptive controller. The reverse brake is interposed between an engine and motor/generator, and the left and right rear wheels and is slip-engaged at a time of starting. The clutch adaptive controller performs clutch adaptive control, in which the reverse brake is subjected to a state in which a temperature of the reverse brake is at, or above, a second threshold for a timed period, at least one time before a vehicle begins to move.

A method of controlling an automatic transmission is provided. The automatic transmission includes a piston having first and second surfaces opposite from each other, friction plates, engaging and disengaging hydraulic pressure chambers for supplying and discharging hydraulic pressure and directing the piston to push the friction plates to be engaged and disengaged, a hydraulic pressure control valve for supplying and discharging hydraulic pressure to and from the chambers, first and second oil paths communicating the valve with the chambers, and a pressure reducing valve disposed in the second oil path and for preventing hydraulic pressure of the disengaging hydraulic pressure chamber from exceeding a given set pressure. The second surface has a larger area for receiving hydraulic pressure than an area of the first surface for receiving hydraulic pressure. The method includes changing the given set pressure according to information regarding a state of the automatic transmission.

A dual clutch transmission comprises a housing formed therein with a gear chamber incorporating an odd-numbered speed gear train group and an even-numbered speed gear train group. An end of the input shaft is connected to an engine, and a cover is detachably attached to the housing opposite the end of the input shaft so as to define a clutch chamber divided from the gear chamber. A first clutch for the odd-numbered speed gear train group and a second clutch for the even-numbered speed gear train group are disposed in the clutch chamber. Fluid passages for supplying hydraulic fluid to the first and second clutches are formed in the cover.