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The invention claimed is: 1. 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, A1, B1, C1, D1, E1), each being electrically actuated by the transmission control device; a plurality of switching valves (A2, D2A, D2B, E2, SV_1, SV_2, SV_3) and a plurality of pressure regulation valves (A3, B3, C3, D3A, D3B, E3), each being actuated by at least one of a plurality of hydra...
The invention claimed is: 1. 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, A1, B1, C1, D1, E1), each being electrically actuated by the transmission control device; a plurality of switching valves (A2, D2A, D2B, E2, SV_1, SV_2, SV_3) and a plurality of pressure regulation valves (A3, B3, C3, D3A, D3B, E3), 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, A1, B1, C1 , D1, E1) 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, A1, B1, C1 D1, E1); 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. 2. The control device according to claim 1, wherein an actuation control pressure (p_D) is provided, via the pressure supply line (27), for engaging the second shift element (D) to implement the reverse drive gear ratio (“R”). 3. The control device according to claim 1, wherein a pilot pressure (p_VS_D) is supplied, via the pressure supply line (32), for actuating at least one of a pressure regulation valve (D3A, D3B) associated with the second shift element (D) and the shift valve (D2A, D2B) associated with the shift element (D) to implement the reverse drive gear ratio (“R”). 4. The control device according to claim 1, wherein the pressure signal (p_sys) at least approximately corresponds to a system pressure (p_sys) set by a system pressure valve (4). 5. The control device according to claim 1, wherein at least when the gearshift lever is in a reverse drive position (“Pos R”), the pressure signal (p_sys) is passed, via the gearshift switch (2), to the engagement prevention valve (SV_3). 6. The control device according to claim 1, wherein when the transmission control device is inactive, a pressure control valve (B1) of the first shift element (B) for obtaining the reversing gear (“R”) is open and a pressure regulation valve (B3) of the first reversing shift element (B) is actuated by the pilot pressure (p_VS_B) to engage the first reversing shift element (B). 7. The control device according to claim 1, wherein when the transmission control device is inactive, a pressure control valve (D1) of the second shift element (D) for obtaining the reversing gear (“R”) is closed and pressure regulation valves (D3A, D3B) and switching valves (D2A, D2B) of the second reversing gear shift element (D) are not actuated by a pilot pressure (p_VS_D) provided by an associated pressure control valve (D1). 8. The control device according to claim 1, wherein when the transmission control device is inactive, a second pressure control valve (D3A, D3B) and a second switching valve (D2A, D2B) of the second reversing shift element (D) are controlled by the system pressure (p_sys) applied to the second pressure regulation valve (D3A, D3B) and the second switching valve (D2A, D2B), via the gearshift switch (2), when the gearshift lever is in a reverse gearshift lever position (“Pos R”), such that a second actuation control pressure (p_D) is applied to the second reversing shift element (D) to implement engagement thereof. 9. The control device according to claim 1, wherein a pressure signal (p_sys) for controlling a second pressure regulation valve (D3A, D3B) and for controlling a second switching valve (D2A, D2B) of the second reversing shift element (D) when the transmission control device is inactive, is passed to the second pressure regulation valve (D3A, D3B) and the second switching valve (D2A, D2B), via an emergency switching valve (SV_2), and a connection between the gearshift switch (2) and the second pressure regulation valve (D3A, D3B) and between the gearshift switch (2) and the second switching valve (D2A, D2B) is blocked in an area of the emergency switching valve (SV_2) when the transmission control device is active. 10. The control device according to claim 1, wherein the engagement prevention valve (SV_3) is additionally actuated in the direction of the second switch position by a further pressure signal (p_VS_A), when the transmission control device is active, to vary a valve characteristic. 11. The control device according to claim 10, wherein the further pressure signal (p_VS_A) corresponds to a pilot pressure (p_VS_A) controlled by a third pressure control valve (A1) which is closed in a de-energized condition. 12. The control device according to claim 10, wherein the further pressure signal (p_VS_A) and the pressure signal are applied on individual active surfaces of a valve slide of the engagement prevention valve (SV_3). 13. The control device according to claim 10, wherein the further pressure signal (p_VS_A) is applied to a common active surface of a valve slide (28) of the engagement prevention valve (SV_3) as the pressure signal (p_sys), and the further pressure signal (p_VS_A) is applied to the common active surface as alternatives, via an OR valve (30).