摘要 |
A control valve arrangement having a clutch regulation valve ( 3 ), which pressurizes a device to actuate the clutch, and a valve that produces a controlled pilot pressure (P_VST 3 ). An electronic control unit (ECU) controls a valve to supply a control valve with the pressure (P_VST 3 ). The arrangement further having a hydraulic system which, if the ECU fails and the pressure (P_VST 3 ) ceases, the last shift condition of the clutch actuation device, prior to the ECU failure, can be maintained in an emergency. The arrangement includes a valve, which delivers an activation pressure (P_A), depending on an engine-speed-dependent control pressure (P_D), to an actuation valve ( 2 ), which then delivers the pressure (P_A) to the valve ( 3 ) to prevent the emergency function initiation despite a lack of pressure (P_VST 3 ) and existance of the pressure (P_D) sufficiently high to initiate the emergency function.
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