| 摘要 |
<p>The invention relates to a gear control device (1), in particular to a motor vehicle automatic gearbox, comprising a hydraulic control system which is controllable by an electric transmission control unit and comprises several pressure control valves (A1 to E1) electrically controllable by said electric transmission control unit, several switching valves (A2, D2A, D2B, E2) and pressure control valves (A3, B3, C3, D3A, D3B, E3) controllable, respectively, by a hydraulic pilot control pressure (p_VS_A bis p_VS_E) adjustable by the pressure control valves (A1 to E1). Each particular pressure control valves (A1 to E1) is associated with each switching element (A to E), respectively. The inventive device also comprises a switch prevention valve (SV_3) which is pressurised by a control pressure (p_B) of a first switching element (B) representing a reverse travel transmission in the direction of a first switch position opposite to a spring device (26) and which is controllable in the direction of a second switching position by means of the pressure signal (p_sys) equivalent to the control pressure (p_B) of the first switching element (5) representing the reverse drive transmission. A pressure supply line (27) of a second switching element (D) representing the reverse drive transmission is locked in the first switch position of the switch prevention valve (SV_3) and is released in the second switch position thereof.</p> |
