A hydraulic arrangement for a vehicle transmission includes a hydraulic pump for providing a system pressure for a first hydraulic system circuit and a lubrication pressure for a second hydraulic lubrication circuit. The arrangement also includes a control valve connected between a pump outlet of the pump and the two hydraulic circuits and has two different switching positions. The control valve, depending on its switching position, acts as a hydraulic connection between the pump and the system circuit or between the pump and the lubrication circuit.

A control device for an automatic transmission is provided, which includes a vehicle-propelling friction engagement element configured to be engaged when a vehicle starts traveling, an other friction engagement element, a vehicle-propelling friction engagement element temperature detector configured to detect a temperature of the vehicle-propelling friction engagement element, an input torque detector configured to detect an input torque inputted into the automatic transmission, and a control unit comprising a lubricant supply control logic configured to control supply of lubricant to the vehicle-propelling friction engagement element and the other friction engagement element. The lubricant supply control logic switches the supply amount of lubricant to the vehicle-propelling friction engagement element according to the temperature of the vehicle-propelling friction engagement element, and switches the supply amount of lubricant to the another friction engagement element according to the input torque.

A power train device for a vehicle is provided with a selector valve that is switched between a first state in which oil discharged from an electric oil pump is able to be supplied as a hydraulic fluid to an engagement hydraulic chamber of a vehicle-starting frictional engagement element, and a second state in which the oil is able to be supplied as a lubricating oil to the vehicle-starting frictional engagement element through a first lubricating oil supply circuit, depending on a magnitude of a discharge pressure of a mechanical oil pump.

A vehicle transfer case is provided having a housing, a primary shaft rotatably mounted within the housing, a secondary shaft selectively driven by the primary shaft, a hub torsionally fixed with the primary shaft, a clutch housing selectively torsionally connected with the hub via a friction pack, an engagement wheel torsionally fixed with respect to the clutch housing and torsionally connected with the secondary shaft via a flexible torsional force member, the friction pack, upon engagement, causing the clutch housing to be selectively connected with the hub, a reservoir system fixed with respect to the housing capturing lubricant energized by result of the operation of the flexible torsional member, the reservoir system delivering splashed lubricant to a reservoir system, and an Archimedes' screw pump delivering lubricant from a sump adjacent to the secondary shaft to the secondary reservoir system.

A hydraulic control unit of a vehicle drive system including an automatic transmission, and an oil pump device, includes: a first electromagnetic valve; a second electromagnetic valve; first and second oil passages; a third oil passage; a manual valve operated to connect and disconnect the first and third oil passages and a drain oil passage to and from each other, in response to an operation of a manually operated shifting device by a vehicle operator, such that the first oil passage is connected to the third oil passage when the shifting device is placed in a first operating position, while the first oil passage is connected to the drain oil passage when the shifting device is placed in a second operating position; an accumulator connected to the first oil passage; and a check valve provided in the second oil passage.

A control apparatus for a vehicle includes an input-rotation limiting portion configured, when the vehicle starts running and is accelerated, to calculate an estimated speed value that is a speed value of an input rotational speed of an automatic transmission upon elapse of a predetermined length of time, and to calculate an estimated force value that is a force value of a piston pressing force acting on a piston in a forward direction in a released engagement device upon the elapse of the predetermined length of time, based on a centrifugal hydraulic pressure in a pressure chamber of the released engagement device and the centrifugal hydraulic pressure in a canceller chamber of the released engagement device. When the estimated force value is not smaller than a predetermined threshold, the input-rotation limiting portion restrains an increase of the input rotational speed.

Because an EOP starts operating from when a decrease in discharge flow rate of an MOP is predicted or detected, a PL actual pressure that should be obtained with a PL command pressure set to a value for a required transmission torque is more easily maintained even when the discharge flow rate of the MOP becomes insufficient. After a lapse of a predetermined period of time from the start of operation of the EOP, the PL command pressure is temporarily set to a value higher than the value for the required transmission torque, and a regulator valve is controlled to operate to close a drain port. Therefore, the operation of the EOP in a high PL actual pressure is reduced, and a delay in response of a pressure regulating operation of the regulator valve in the process of reduction of the discharge flow rate of the MOP is reduced.

The present invention relates to an auxiliary transmission brake arrangement (100) for a transmission (10) of a vehicle. In particular, the invention relates to an auxiliary transmission brake arrangement comprising a lubrication arrangement for improved lubrication of gear wheels connecting the auxiliary transmission brake arrangement to an output shaft.

A hydraulically actuated transmission includes a selecting switching valve configured to selectively switch between a first switching valve and a second switching valve as a valve to be connected with an outlet port of a solenoid valve. The selecting switching valve is configured to operate in response to a hydraulic pressure applied to a specific frictional coupling element (second brake) in accordance with coupling and releasing of the specific frictional coupling element, and is configured to connect the outlet port with the first switching valve while the hydraulically actuated transmission is in high gear which is higher than or equal to a predetermined gear, and connect the outlet port with the second switching valve while the hydraulically actuated transmission is in the low gear which is lower than the predetermined gear.

A hydraulic controlling system including: a cooling and lubricating oil line and a main controlling oil line; an oil-liquid storage; a first pump, wherein an inlet of the first pump is connected to the oil-liquid storage and an outlet of the first pump is connected to the main controlling oil line; a second pump, wherein an inlet of the second pump is connected to the oil-liquid storage and an outlet of the second pump selectively communicates with the cooling and lubricating oil line or the main controlling oil line; and a gearbox-gear-shifting oil line including a gear-shifting-pressure regulating valve, a plurality of gear-shifting-flow-rate controlling valves and a plurality of gear-shifting selector valves. The gear-shifting-flow-rate controlling valves are connected to the main controlling oil line via the gear-shifting-pressure regulating valve. At least some of the gear-shifting-flow-rate controlling valves are connected to a gear-shifting executing piston via the gear-shifting selector valves.