| 摘要 |
PURPOSE:To ensure stable operation of a vehicle when constant-speed driving control is executed in a relatively low-speed region, by cancelling the constant- speed driving control in case that the actual vehicle speed becomes lower than a prescribed vehicle speed while executing the constant-speed driving control. CONSTITUTION:When a set switch 12 is once closed and then opened after closing a main switch 10, a condition judging circuit 9 in a constant-speed driving unit 1 judges that the vehicle speed is set. Thereupon, actual vehicle-speed data D1 obtained through A/D conversion 17 of the output of a vehicle-speed signal generating section 7 is stored in a first memory 16 as an aimed vehicle-speed data Dt. When the desired vehicle-speed is thus set and constant-speed driving control s executed, judgement is made on whether the actual vehicle speed at each time lies within a prescribed vehicle-speed region. In case of ''NO'', a reset signal RS2 is produced from a reset circuit 21, and the constant-speed driving control is nullified by resetting the condition judging circuit 9 and an amplifier 19. |
