Patent ID: 7794349

Claim:
A control device ( 1 ) for an automatic transmission of a vehicle, having a hydraulic control system that is controllable by an electric transmission control device, the control device comprising: a plurality of pressure control valves ( 5 , A 1 , B 1 , C 1 , D 1 , E 1 ), each being electrically actuated by the transmission control device; a plurality of switching valves (A 2 , D 2 A, D 2 B, E 2 , SV_ 1 , SV_ 2 , SV_ 3 ) and a plurality of pressure regulation valves (A 3 , B 3 , C 3 , D 3 A, D 3 B, E 3 ), each being actuated by at least one of a plurality of hydraulic pilot pressures (p_VS_ 5 , p_VS_A, p_VS_B, p_VS_C, p_VS_D, p_VS_E); the plurality of hydraulic pilot pressures (p_VS_ 5 , p_VS_A, p_VS_B, p_VS_C, p_VS_D, p_VS_E) are set by one of the plurality of pressure control valves ( 5 , A 1 , B 1 , C 1 , D 1 , E 1 ) such that the hydraulic control system, depending on a gearshift lever position (“Pos D”, “Pos R”, “Pos N”, “Pos P”) of a manual gearshift switch ( 2 ), enables application of a hydraulic actuation control pressure (p_A, p_B, p_C, p_D, p_E) of at least two of a plurality of shift elements (A, D; A, C; A, B; A, E; B, E; C, E; B, D) to one of engage and disengage a variety of gears ratios (“1”, “2”, “3”, “4”, “5”, “6”, “R”) for implementing at least one of a forward drive and a reverse drive, each of the plurality of shift elements (A to E) is associated with one of the plurality of pressure control valves ( 5 , A 1 , B 1 , C 1 D 1 , E 1 ); at least one reverse drive gear ratio (“R”) being implemented by simultaneous engagement of first and second shift elements (B, D); simultaneous engagement of the first shift element (B), the second shift element (D) and at least one other of the plurality of shift elements (A, E) implements one gear ratio (“1”, “3”, “5”) for forward drive; and an engagement prevention valve (SV_ 3 ) being actuated by a control pressure (p_B) of the first shift element (B), against a spring device ( 26 ), in a direction of a first switch position to obtain the reverse drive gear ratio (“R”) and the engagement prevention valve (SV_ 3 ) is actuated in a direction of a second switch position by a pressure signal (p_sys) equivalent to the control pressure (p_B) of the first shift element (B) for implementing the reverse drive gear ratio (“R”); and a pressure supply line ( 27 ; 32 ) of the second shift element (D) being blocked when the engagement prevention valve (SV_ 3 ) is in the first switch position and being open when the engagement prevention valve (SV_ 3 ) is in the second switch position.