Abstract: A hydraulic system for a vehicle clutch assembly can include a pump and a purge valve for regulating hydraulic pressure supplied to the clutch. The hydraulic pressure at the pump can be set to a value higher than the operating pressure for the clutch. The purge valve can be configured to purge hydraulic pressure from the hydraulic system so that an optimum, controllable, and/or pre-determined operating pressure can be supplied to the clutch. The system can be configured to provide accurate control of the clutch(es), continuous cooling capacity to the hydraulic system components, lateral torque control when two separate hydraulic circuits are used, weight and cost reduction of the vehicle clutch, as well as other vehicle functions and characteristics.

Abstract: A hydraulic system for a vehicle clutch assembly can include an on-demand variable displacement pump and a purge valve for regulating hydraulic pressure supplied to the clutch(es). The hydraulic pressure at the pump can have multiple displacement settings to compensate for variable changes in clutch pressure requirements. The purge valve can be configured to purge hydraulic pressure from the hydraulic system so that an optimum, controllable, and/or pre-determined operating pressure can be supplied to the clutch(es). The system can be configured to provide accurate control of clutch(es) when a drivetrain is being automatically controlled to switch between a low gear ratio and a high gear ratio.

Abstract: A hydraulic system for a vehicle clutch assembly can include an on-demand variable displacement pump and a purge valve for regulating hydraulic pressure supplied to the clutch(es). The hydraulic pressure at the pump can have multiple displacement settings to compensate for variable changes in clutch pressure requirements. The purge valve can be configured to purge hydraulic pressure from the hydraulic system so that an optimum, controllable, and/or pre-determined operating pressure can be supplied to the clutch(es). The system can be configured to provide accurate control of clutch(es) when a drivetrain is being automatically controlled to switch between a low gear ratio and a high gear ratio.

Abstract: A hydraulic system for a vehicle clutch assembly can include a pump and a purge valve for regulating hydraulic pressure supplied to the clutch. The hydraulic pressure at the pump can be set to a value higher than the operating pressure for the clutch. The purge valve can be configured to purge hydraulic pressure from the hydraulic system so that an optimum, controllable, and/or pre-determined operating pressure can be supplied to the clutch. The system can be configured to provide accurate control of the clutch(es), continuous cooling capacity to the hydraulic system components, lateral torque control when two separate hydraulic circuits are used, weight and cost reduction of the vehicle clutch, as well as other vehicle functions and characteristics.

Abstract: A hydraulic system for a vehicle clutch assembly can include a pump and a purge valve for regulating hydraulic pressure supplied to the clutch. The hydraulic pressure at the pump can be set to a value higher than the operating pressure for the clutch. The purge valve can be configured to purge hydraulic pressure from the hydraulic system so that an optimum, controllable, and/or pre-determined operating pressure can be supplied to the clutch. The system can be configured to provide accurate control of the clutch(es), continuous cooling capacity to the hydraulic system components, lateral torque control when two separate hydraulic circuits are used, weight and cost reduction of the vehicle clutch, as well as other vehicle functions and characteristics.

Abstract: An improvement is made to a torque splitting device employing hydraulic clutches so as to avoid any discontinuity in the control even when the properties of the actuating oil such as the pressure and temperature thereof deviate from standard values. For instance, when the oil temperature is low, the target value of the oil pressure for each of the clutches is modified to a lower value. Thus, it becomes possible to make less pronounced any delay in the response of the torque splitting device which may arise due to the sluggishness of the oil as it flows out of the clutch cylinder. The oil pump is typically actuated by a member rotating at a speed proportional to the vehicle speed, and the pressure output of the pump may be inadequate in a low speed range. In such a case, the target value is again reduced so as to reduce any abrupt change in the property of the torque splitting device when the vehicle is accelerated from a low speed.

Abstract: A driving force distributing device is provided for distributing a driving force of an engine to the left and right wheels of a vehicle by bringing a pair of hydraulic clutches into and out of their engaged states. The distributing device includes a hydraulic pump mounted within a casing thereof and driven through gears by a half shaft connected to one of the wheels. An oil passage interconnects the hydraulic pump and the hydraulic clutches, the oil passage being defined in a casing. A valve block is coupled to an upper surface of the casing. Thus, the oil passages interconnecting the hydraulic pump and the hydraulic clutches of the driving force distributing device can be compactly formed.

Abstract: A ring gear of a differential connected to an engine, and a sun gear and a planetary carrier are connected to left and right output shafts of the differential. A first pinion and a second pinion integrally formed and having different circle radii are carried on a carrier member which is rotatably fitted over the left output shaft. The first pinion is connected to the right output shaft, while the second pinion is connected to the left output shaft. When a hydraulic clutch is brought into an engaged state during clockwise turning of a vehicle, the carrier member is decelerated to accelerate a left front wheel, and a torque is transmitted to the left front wheel. When a hydraulic clutch is brought into an engaged state during counterclockwise turning of a vehicle, the carrier member is accelerated to accelerate a right front wheel, and a torque is transmitted to the right front wheel.

Abstract: In order to achieve a gear ratio control of a continuously variable transmission, a transmission gear ratio is controlled based on a difference between an actual engine speed and a target engine speed to be set in response to a first parameter corresponding to an accelerator opening. When controlling the transmission gear ratio, a plurality of change characteristics of the transmission gear ratio are set for, in particular, the kickdown gear shifting. In response to a second parameter representing the driver's demand for a traveling condition, a change characteristic of the transmission gear ratio is selected from among the plurality of change characteristics of the transmission gear ratio, to execute the speed ratio control in accordance with the thus selected change characteristic of the transmission gear ratio when a kickdown gear shifting is needed.