Patent ID: 7771317

Claim:
A control valve arrangement for activating and controlling at least one start-up clutch of a vehicle automatic transmission during one of a hydraulic emergency operation caused by an electronic control device failure or an absence of a pilot pressure (P_VST 3 ), the valve arrangement comprising: at least one pressure regulating valve ( 166 ) being controlled by the electronic control device to supply the control valve arrangement with the pilot pressure (P_VST 3 ); at least one clutch regulating valve ( 3 , 3 ′, 3 ″) directing a flow of supply pressure (P_V 1 ) to a pressure chamber of a clutch activation device ( 4 , 4 ′); a self-maintaining hydraulic unit comprising a self-maintaining valve ( 1 ) and an activation valve ( 2 ) and sustains engagement of the at least one start-up clutch during the hydraulic emergency operation; the self-maintaining valve ( 1 ) communicating with the activation valve ( 2 ) and directing an activation pressure (P_A) to the activation valve ( 2 ) depending on a control pressure (P_D), which is dependent upon at least one of a motor rotational speed and a transmission output rotational speed and the activation valve ( 2 ) directs the activation pressure (P_A) to the at least one clutch-regulating valve ( 3 , 3 ′, 3 ″); the control valve arrangement controlling one of activation and de-activation of the hydraulic emergency operation with a clutch activation pressure (P_K, P_K′); the clutch activation pressure (P_K, P_K′) being passable through a first line ( 41 ), a pressure chamber ( 44 ) of the activation valve ( 2 ) and a second line ( 42 ) to a pressure chamber ( 43 ) of the self-maintaining valve ( 1 ), and the clutch activation pressure (P_K, P_K′) being passable from the pressure chamber ( 43 ) of the self-maintaining valve ( 1 ) through a third line ( 47 ) to a pressure chamber ( 38 ) which is located at an end of the self-maintaining valve ( 1 ) opposite a resetting spring ( 31 ) of the self-maintaining valve ( 1 ).