A drag torque reduction device for an automatic transmission includes a hydraulic controller with a parallel connection of a pressure relief valve, a constant aperture and a temperature-dependent, switchable aperture that is positioned upstream of a radiator relative to a flow of fluid to the radiator. The parallel connection is disposed between a first control edge of a converter switching valve and a first line. The first line leads to both to the radiator and through a check valve to the converter ring. The first control edge of the converter switching valve is open and lubricating oil flows through the parallel connection when the converter switching valve is in a first switching position. The first control edge of the converter switching valve is closed and lubricating oil does not flow through the parallel connection when the converter switching valve is in a second switching position.

A hydraulic control apparatus for a vehicle including a first flow path leading oil discharged from a first hydraulic pump to a driving unit, a second flow path leading oil discharged from a second hydraulic pump to a lubrication unit, a flow path switching unit switching a flow path, and a controller controlling the flow path switching unit so as to lead the oil discharged from the second hydraulic pump to the first flow path when inoperation of an accelerator is detected and vehicle speed less than or equal to a predetermined value which is greater than 0 is detected, and to lead the oil discharged from the second hydraulic pump to the lubrication unit when operation of the accelerator is detected or vehicle speed greater than the predetermined value is detected.

Methods and valves for providing a continuous flow of cooler fluid in a fluid circuit of a thermal control system between a cooler and automotive transmission such that free flow of cooler fluid between the cooler and transmission exists at vehicle start-up. Fluid flow to and from the cooler is bypassed in case of pressure increases in cooler lines or pressure differentials, for example cause by a blockage in the cooler, such that the cooler fluid flow bypasses the cooler and continues in the fluid circuit through a thermal element of the thermal control system and back to the transmission.

Methods and systems are provided for adjusting a lubrication system based on an axle configuration of a tandem axle with a disconnect feature. In one example, a method may include adjusting an oil level in an axle sump of a tandem axle based on an axle configuration of the tandem axle (e.g., whether the tandem axle is operating with one of a 6×4 axle configuration and a 6×2 axle configuration), the axle sump selectably coupled to an external reservoir via a first passage and a second passage, the first passage including an electric pump, the second passage including a valve, and the tandem axle coupled to a drivetrain of a motor vehicle. In this way, an amount of oil in the axle sump may be adjusted based on the tandem axle configuration.

The present invention includes a bypass apparatus for lubricant in an unregulated pressurized gearbox including: a block including a lubricant inlet in fluid communication with a pressure relief valve, wherein the pressure relief valve diverts lubricant into the gearbox or into an oil filter, wherein lubricant is returned to the gearbox when the lubricant is cold and/or pressure at the pressure relief valve is high to reduce damage to the gearbox caused by high pressure during a cold start, and when the lubricant temperature increases and the pressure is reduced the pressure relief valve closes and lubricant enters the oil filter.

A drive assembly for a motor vehicle includes a housing having a transmission housing chamber, a reservoir, and a clutch housing chamber. At least one of the transmission housing chamber or the clutch housing chamber are fluidically connected to the reservoir. A transmission is disposed in the transmission housing chamber. A clutch is disposed in the clutch housing chamber. The clutch is drivingly connected to the transmission. An actuator has an actuating element engaged with the clutch. The clutch is moveable by the actuating element between a disengaged position and an engaged position. A valve is operatively connected to the actuating element of the actuator to allow lubricant flow from the reservoir to at least one of the transmission housing chamber and the clutch housing chamber when the clutch is in the engaged position and to prevent lubricant flow from the reservoir when the clutch is in the disengaged position.

A drive device has a superimposed transmission, an input shaft connected a main drive machine, one or more auxiliary drives, a hydrodynamic retarder for braking the auxiliary drive, and an output shaft to be connected to a working machine. The superimposed transmission has a planetary transmission, with the input shaft connected to a ring gear and the output shaft connected to a sun gear. The retarder is incorporated into a lubricating oil system of the drive device in parallel. A feed line branches from the lubricating oil system and leads to the retarder. A return line leads from the retarder and opens into the lubricating oil system. A valve enables the feed line to be released in the event of a rapid disconnection or energy supply failure of one of the drives, and thus the retarder can be filled with oil.

A thermal management for a hybrid vehicle is provided. The system includes an engine coolant to cabin air heat exchanger in a first heat exchange loop and being operably coupled to an engine coolant circuit and cabin air in the vehicle, respectively, a transmission fluid to engine coolant heat exchanger in a second heat exchange loop and being operably coupled to a transmission fluid circuit and the engine coolant circuit, respectively, a control valve operable to control a flow of engine coolant through at least the second heat exchange loop, and a control module configured to selectively operate the control valve to initiate or restrict the flow through the second heat exchange loop to provide heat to the transmission fluid circuit based on ambient temperature, transmission fluid temperature and engine coolant temperature. The control module is further configured to enable control functions associated with transmission operation and hybrid functions based on the transmission fluid temperature.

An oil supply device has: a first hydraulic pump driven by power transmitted through a power transmission path; a second hydraulic pump driven by a second driving force source independent from the power transmission path; and a hydraulic circuit. In a specific state in which a first forward speed is formed by oil discharged from the second hydraulic pump being supplied to a hydraulic drive portion, when a failure occurs in which a discharge pressure of the second hydraulic pump is decreased, a state of the hydraulic circuit is switched from a first state in which oil discharged from the second hydraulic pump is supplied to the hydraulic drive portion to a second state in which oil discharged from the first hydraulic pump is supplied to the hydraulic drive portion.

A gear transmission unit, particularly for a motor-vehicle, is provided with a forced lubrication system for lubricating rolling bearings and/or further inner components of the transmission unit. The unit is provided with one or more accessory elements in the form of lubricant distribution boxes. Each distribution box has a hollow body rigidly connected to the casing of the unit adjacent to a respective channel outlet which supplies a flow of lubricant under pressure. The hollow body defines an inner lubricant distribution chamber and has an inlet connected to the channel outlet and two or more outlets connected to further conduits for channels or chambers, for supplying the flow of lubricant under pressure in parallel to various components to be lubricated inside the transmission casing.