A hydraulic assembly for a vehicle transmission includes a hydraulic pump for providing a system pressure within a hydraulic circuit, a pressure accumulator for temporarily supplying pressure to the hydraulic circuit, and a valve assembly for charging the pressure accumulator after a predetermined pressure threshold value of the system pressure has been reached or exceeded. The valve assembly is hydraulically connected between the pump and the pressure accumulator.

A hydraulic assembly for a vehicle transmission includes a hydraulic pump for providing a system pressure within a hydraulic circuit, a pressure accumulator for temporarily supplying pressure to the hydraulic circuit, and a valve assembly for charging the pressure accumulator after a predetermined pressure threshold value of the system pressure has been reached or exceeded. The valve assembly is hydraulically connected between the pump and the pressure accumulator.

A hydraulic system for an automatic transmission of a motor vehicle. A high pressure circuit in which a pressure accumulator, at least one clutch as well as gear selectors and at least one hydraulic pump are arranged, which can be controlled by an electronic control unit. The pressure accumulator can be connected to a hydraulic positioning cylinder via at least one hydraulic path, wherein a control valve that can be controlled by the control unit is arranged upstream thereof, with which a hydraulic pressure at the hydraulic positioning cylinder can be adjusted, and which control valve can be moved between two through-flow positions in order to move a piston in opposing piston strokes via opposing piston travel paths as well as piston speeds in the hydraulic positioning cylinder.

A hydraulic system for an automatic transmission of a motor vehicle. A high pressure circuit in which a pressure accumulator, at least one clutch as well as gear selectors and at least one hydraulic pump are arranged, which can be controlled by an electronic control unit. The pressure accumulator can be connected to a hydraulic positioning cylinder via at least one hydraulic path, wherein a control valve that can be controlled by the control unit is arranged upstream thereof, with which a hydraulic pressure at the hydraulic positioning cylinder can be adjusted, and which control valve can be moved between two through-flow positions in order to move a piston in opposing piston strokes via opposing piston travel paths as well as piston speeds in the hydraulic positioning cylinder.

A drop-in signal accumulator piston assembly replaces an original equipment (OE) signal accumulator piston in a vehicle transmission hydraulic circuit. The OE signal accumulator piston is positioned in a bore in a valve body that has an open end and a fluid port. The drop-in signal accumulator piston assembly includes a cylindrical sleeve having open first and second ends and a piston positioned in the sleeve. A spring is positioned in part in the piston and in part extending beyond and end of the piston. A plug is positioned in the bore adjacent the sleeve. The sleeve is positioned in the valve body bore, with the piston, and the spring, and the plug is positioned in the valve body bore to enclose the sleeve, the piston and the spring in the valve body bore. A method for replacing an original equipment (OE) signal accumulator piston in a transmission hydraulic circuit is disclosed.

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 transmission hydraulic control system for an automobile transmission includes a hydraulic circuit in fluid communication with the at least one torque transmitting device, a transmission pump in fluid communication with the hydraulic circuit and adapted to provide pressurized hydraulic fluid to the hydraulic circuit, an accumulator in fluid communication with the hydraulic circuit and having an annular cylindrical shape concentric with a center-line of the automatic transmission, an annular piston moveable between a first position and a second position, and a spring adapted to bias the piston to the first position, and a valve mechanism positioned between the hydraulic circuit and the accumulator, the valve mechanism adapted to selectively allow fluid communication between the accumulator and the hydraulic circuit.

A hydraulic switching assembly for a motor vehicle, having a hydraulic pump (1) which guides a hydraulic medium from a reservoir (2) via hydraulic lines (3) and at least one magnetic valve assembly (4) including a magnetically actuatable switching valve (5), to a switching element (6) in order to hydraulically actuate the switching element (6) between two switching positions. A pressure accumulator (7) and a first check valve (8a) are mounted in a supply line (3a) upstream of the switching valve (5) in order to realize a reliable temporary supply of oil pressure to the switching element (6).

A drop-in signal accumulator piston assembly replaces an original equipment (OE) signal accumulator piston in a vehicle transmission hydraulic circuit. The OE signal accumulator piston is positioned in a bore in a valve body that has an open end and a fluid port. The drop-in signal accumulator piston assembly includes a cylindrical sleeve having open first and second ends and a piston positioned in the sleeve. A spring is positioned in part in the piston and in part extending beyond and end of the piston. A plug is positioned in the bore adjacent the sleeve. The sleeve is positioned in the valve body bore, with the piston, and the spring, and the plug is positioned in the valve body bore to enclose the sleeve, the piston and the spring in the valve body bore. A method for replacing an original equipment (OE) signal accumulator piston in a transmission hydraulic circuit is disclosed.

A vehicle having a controller is provided. The controller may be configured to, responsive to identification of a braking event predicted to occur in the future, hydraulically charge an accumulator, and responsive to a pressure of the accumulator exceeding a first threshold, cease charging the accumulator, and satisfy transmission line pressure demand with pressure from the accumulator to begin depleting the accumulator to a before initiation of the braking event.