| 摘要 |
The invention pertains to a hydraulic control system for servos in automatic transmissions, which, in a known fashion, utilizes a main pressure valve to regulate the pressure within the control system and further utilizes a converter pressure valve to supply a hydrodynamic torque converter and the lubrication system. The servos (for example, the clutches) utilized in this type of automatic transmissions cooperate with electromagnetically actuated pressure regulating valves have a current-proportional response. These electromagnetic valves are actuated by electronic control signals generated by sensors which monitor various parameters during operation, making previously utilized sensors superfluous. By control of the pressure regulating valves the forward gear, the reverse gear or the neutral gear can be engaged in the simplest fashion. By means of a magnet valve associated with the main pressure valve the levels of pressure may be varied. It is also possible, via simple associated elements, to install an emergency system which during a failure of the electrical system allows the transmission to continue to operate. |
