An automatic transmission comprising a control valve body adapted to control oil flow within the transmission, a torque converter having a torque converter clutch operable in one of an open and an applied condition, a first control circuit between the control valve body and the torque converter and a second control circuit between the control valve body and the torque converter, a first oil path that provides a fluid connection between the first control circuit and the torque converter, a second oil path that provides a fluid connection between the second control circuit and the torque converter, a third oil path that provides a fluid connection between the second control circuit and the torque converter clutch, and an orifice that provides a fluid connection between the second control circuit and the torque converter.

A vehicle power transmission device includes: a continuously variable transmission including a primary pulley, a secondary pulley, and a transmission belt wound between the primary pulley and the secondary pulley; a belt running clutch of hydraulic type for transmitting power to the continuously variable transmission; and a hydraulic control circuit controlling the continuously variable transmission and the belt running clutch. The hydraulic control circuit includes a fail-safe valve switching a communication destination of an oil supply passage for supplying a hydraulic fluid to the belt running clutch to one of a first oil passage supplied with a control hydraulic pressure and a second oil passage supplied with a hydraulic pressure higher than the control hydraulic pressure, the fail-safe valve connecting the oil supply passage with the second oil passage when the fail-safe valve is switched to a failure position. The second oil passage is provided with an orifice.

The invention relates to an apparatus having a plurality of hydraulic actuators (S.sub.i) and a piston-cylinder unit (K), one working chamber (AK.sub.1) of which is connected, via at least one hydraulic connection line (HL) and supply lines (ZL.sub.i), to working chambers (AS.sub.i) of the hydraulic actuators (S.sub.i), wherein each working chamber (AS.sub.i) of a hydraulic actuator (S.sub.i) is connected to a supply line (ZL.sub.i) and switch valves (EV.sub.i) for selective opening and closing of the hydraulic supply lines (ZL.sub.i) are provided such that, in the opened position of the associated switch valve (EV.sub.i), a pressure change in the working chamber (AS.sub.i) of the actuator (S.sub.i) or an adjustment of the actuator (S.sub.i) can occur, wherein at least one pressure sensor (DS.sub.i) for determining the pressure in a working chamber (AS.sub.i) of an actuator (S.sub.i) or a hydraulic line (HL, ZL.sub.i, AL.sub.i) and a control device (ECU) is provided, characterized in that, for simultaneous pressure change in at least two actuators, (S.sub.i, S.sub.k), the (ECU) permanently opens the switch valve (EV.sub.i) associated with a first actuator (S.sub.i) during the pressure change phase and adjusts or regulates the pressure by adjusting the piston (KK) of the piston-cylinder unit (K), and in that the control device (ECU) adjusts or regulates the pressure in at least one additional actuator (S.sub.k) by means of the switch valve (EV.sub.k), which is clocked during the pressure change phase, and in particular is controlled by pulse width modulation.

A hydraulic actuating device for actuating a shifting element of a transmission includes a hydraulic cylinder with a piston rod and a piston chamber, wherein the piston rod can be brought into a mechanical operative connection with the shifting element, and a hydraulic pump which is connected via a hydraulic line to the piston chamber, in order for it to be possible for hydraulic fluid to be fed to the piston chamber and thus to initiate an adjusting movement of the piston rod. The actuating device is characterized by a shut-off device, via which the hydraulic fluid can be locked in the piston chamber, in order thus to fix the position of the piston rod.

An automatic transmission assembly for mounting to a power-source includes a torque converter operatively connected to the power-source. The transmission assembly also includes a turbine shaft for receiving power-source torque from the torque converter. The transmission assembly additionally includes a torque transfer system, having a gear-train and a hydraulic pressure operated torque-transmitting device, for receiving the torque from the turbine shaft and selecting an input-to-output speed-ratio of the transmission. The transmission assembly also includes an output member for receiving torque from torque transfer system and outputting the torque to drive a load. The turbine shaft defines a first passage configured to supply hydraulic pressure to the torque-transmitting device and a second passage configured to vent to atmosphere. The turbine shaft additionally defines a third passage fluidly connecting the first passage to the second passage and thereby configured to bleed air from the torque-transmitting device.

A valve body for an automotive transmission includes a pressure regulator valve in the casting for controlling oil pressure within the torque converter. The valve has a bore to provide fluid communication with an exhaust circuitry in the transmission when the valve is moved by oil pressure from a first position to a second position. The regulator valve prevents excessive pressure and damage from ballooning of the torque converter housing. In an alternative non-lockup torque converter, a check ball in a modified separator plate moves to open and close an oil path in the plate to thereby control oil pressure.

A piston for an electromagnetically actuatable hydraulic valve wherein the piston is configured cylindrical and axially movable along a central opening that extends along a longitudinal axis of a housing of the electromagnetically actuatable hydraulic valve, wherein plural connections of the housing are opened or closed according to a position of the piston wherein the plural connections are flow connected with the central opening, wherein the hydraulic valve is hydraulically actuatable by a signal element, wherein a damping system is provided for reducing oscillations of a signal pressure of the signal element that impacts the piston, and wherein the damping system is configured in the piston that includes a receiving cavity for receiving the damping system.

A cooling prioritization valve (5) for a hydraulic system (4) of a motor vehicle transmission (3) includes a valve housing (6), a valve slide (7), an inlet (18), an outlet (15), and a further outlet (21). A secondary system pressure circuit (39) of the hydraulic system (4) can be connected to the inlet (18), a cooler (54) can be connected to the outlet (15) or to the further outlet (21), and a suction loading (44) can be connected to the outlet (15) or to the further outlet (21). In a starting position, the inlet (18) is not connected either to the outlet (15) or to the further outlet (21). In a first control position, the inlet (18) is connected to the outlet (15). In a second control position, the inlet (18) is connected to the outlet (15) and the further outlet (21).

Provided is a control device for a continuously variable transmission, which is capable of effectively preventing occurrence of surge pressure due to a stroke of a driven pulley being stopped by abutment. The control device for the continuously variable transmission includes a pressure regulating valve regulating an oil pressure of oil supplied from an oil supply source to a cylinder chamber of the driven pulley, a control valve controlling the pressure regulating valve, and a control part controlling the control valve. If the control part determines that a gear ratio of the continuously variable transmission is maximum, as a first condition, when an instructed oil pressure of the control valve for the pressure regulating valve is larger than an oil pressure of oil supplied from the pressure regulating valve to the driven pulley, a control for lowering the instructed oil pressure is performed.

An actuator arrangement for a motor vehicle transmission includes a pump device, a shifting interface, and a switching logic device. The pump device has a pump for fluidic actuation of a clutch, and an electric motor for driving the pump. The shifting interface is connected to the pump device for actuating the motor vehicle transmission. The shifting interface has at least one of a shift lever, a shifting pawl mechanism, or a shifting shaft. The switching logic device is arranged between the shifting interface and the pump device. The pump device is arranged to actuate the shifting interface sequentially with respect to the clutch.