Gear device's i.e. eight-gear-automatic gear device, switching unit transmission capability adjusting device for vehicle, has valve device whose connection is provided in hydraulic line during positive pressure drop between line parts

摘要

The device (12) has a pressure control valve (6B), a switch-over valve (7B), and a pressure regulation valve (8B), by which a pre-control pressure is adjusted such that the pressure control valve and the switch-over valve are loadable in an area of control surfaces for adjusting of an operating pressure. One of piston areas (10A, 10B) is brought in effective connection with a hydraulic fluid reservoir (16) via a hydraulic line (14). An effective connection of a locking valve device (15) is provided in the hydraulic line during positive pressure drop between a line part (14A) at a side of the piston area and a line part (14B) at a side of the reservoir. An independent claim is also included for a method of operating a switching unit of a transmission device.