A fluid assembly in a hydraulic circuit, comprising one or more reservoirs configured to store fluid. The fluid assembly also includes a pump configured to transport the fluid in the hydraulic circuit and actuate a load from a transmission of a motor vehicle, a pressure accumulator configured to collect pressure built up by the pump and actuate the load, and a valve system configured to allow fluid communication of the load with the pump.

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.

An oil pressure supply device supplies, to an oil chamber, an oil pressure generated by suctioning oil from an oil source with an oil pump. The oil pressure supply device includes a first oil passage connected to a suction side of the oil pump; a first check valve provided in the first oil passage and configured to close the first oil passage and prevent oil from moving to the oil source side when the oil pump is stopped; a second oil passage connected to a discharge side of the oil pump; and a second check valve provided in the second oil passage and configured to close the second oil passage and prevent oil from moving to the oil pump side when the oil pump is stopped. When the oil pump is stopped, the second check valve closes the second oil passage earlier than the first check valve closes the first oil passage.

Disclosed is a method for operating a multi-speed vehicle transmission having a plurality of shift elements (A, B, C, D, E) for engaging the gears of the vehicle transmission. The method includes decoupling between an input (AN) and an output (AB) of the vehicle transmission in a neutral gear, and coupling the input (AN) and the output (AB) of the vehicle transmission in a drive gear for propelling the vehicle by closing at least one shift element (B). At least one transmission state is determined when the neutral gear is engaged, where a shift element (D) for a reverse gear of the vehicle transmission is closed at least partially if the transmission is in a state with increased drag losses when the neutral gear is engaged.

Disclosed is a method for operating a multi-speed vehicle transmission having a plurality of shift elements (A, B, C, D, E) for engaging the gears of the vehicle transmission. The method includes decoupling between an input (AN) and an output (AB) of the vehicle transmission in a neutral gear, and coupling the input (AN) and the output (AB) of the vehicle transmission in a drive gear for propelling the vehicle by closing at least one shift element (B). At least one transmission state is determined when the neutral gear is engaged, where a shift element (D) for a reverse gear of the vehicle transmission is closed at least partially if the transmission is in a state with increased drag losses when the neutral gear is engaged.

A fluid system for a continuously variable transmission includes a first pump, a first actuation unit, a first line section, a second actuation unit, and a second line section. The first pump has a first sub-pump and a second sub-pump. The first actuation unit is assigned to a first disc set of the continuously variable transmission and the second actuation unit is assigned to a second disc set of the continuously variable transmission. The first line section fluidically connects the first pump to the first actuation unit and the second line section fluidically connects the first pump to the second actuation unit. The second sub-pump has a first connection that can be selectively fluidically connected to the first actuation unit via the first line section, or the second sub-pump has a second connection that can be selectively fluidically connected to the second actuation unit via the second line section.

A fluid system for a continuously variable transmission includes a first pump, a first actuation unit, a first line section, a second actuation unit, and a second line section. The first pump has a first sub-pump and a second sub-pump. The first actuation unit is assigned to a first disc set of the continuously variable transmission and the second actuation unit is assigned to a second disc set of the continuously variable transmission. The first line section fluidically connects the first pump to the first actuation unit and the second line section fluidically connects the first pump to the second actuation unit. The second sub-pump has a first connection that can be selectively fluidically connected to the first actuation unit via the first line section, or the second sub-pump has a second connection that can be selectively fluidically connected to the second actuation unit via the second line section.

A piston, in particular for a gear-change selector, including a piston body with a piston skirt and with a piston end face which can be pressurised with a working fluid. The piston includes a first sealing portion and a second sealing portion. The piston body and the first sealing portion have mutually complementary geometries so that they form a first vent channel. The first vent channel is arranged in a hydraulic series circuit with the second sealing portion. The second sealing portion prevents venting up to a first pressure and allows this above the first pressure. The invention furthermore concerns a gear-change selector and a gearshift for a vehicle.

A piston, in particular for a gear-change selector, including a piston body with a piston skirt and with a piston end face which can be pressurised with a working fluid. The piston includes a first sealing portion and a second sealing portion. The piston body and the first sealing portion have mutually complementary geometries so that they form a first vent channel. The first vent channel is arranged in a hydraulic series circuit with the second sealing portion. The second sealing portion prevents venting up to a first pressure and allows this above the first pressure. The invention furthermore concerns a gear-change selector and a gearshift for a vehicle.