| 摘要 |
The invention relates to a hydraulic control device for power shift transmissions, especially for automatic transmissions of motor vehicles. A pressure line can be connected by way of a selector slide valve (23) to a main pressure line in which a pressure medium source (17) delivers pressure medium for the actuation of shift elements, such as clutches A to D or the like. Two pressure control valves (31, 32) with proportional pressure characteristic are connected to the main pressure line (36) by way of a shuttle valve (28) for shifting of the gears. In addition two solenoid valves (67, 71) are provided, which together with a reversing valve (65) undertake the actuation of three shift valves (34, 40, 73) for determining the individual gears. With the two pressure control valves the individual shifts can be undertaken with overlap control and the one-way clutches in the transmission can be omitted without thereby having to sacrifice the greatest possible degree of safety. Constant engaging of a plurality of gears or a gear shift in which the shift element to be released remains under full system pressure is not possible. <IMAGE>
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