Device and method for controlling the pressure of a hydraulic circuit

摘要

The oil supply with an orientation toward requirements in a transmission is implemented by a system of control and regulating modules. Mentioned in particular, here is a combined control and regulating module that is electronically driven and mechanically regulates the pressure. The controlled variable is a coil current that increases proportionally as the pressure increases. One disadvantage is that, in the case of a system failure, no coil current flows and the pressure is also minimal. In the present invention, by contrast, a maximum pressure is provided in the hydraulics even without current. This ensures that during a system failure that the operation of control elements that can only be shifted using high pressure will continue. This is implemented via a combined control and regulating module. The control unit is a magnet system that moves the regulating module and a sliding valve (14). Moreover, a spring system is provided that holds the sliding valve (14) at the starting position when no current is present.