PURPOSE: To eliminate need of an auxiliary brake switch, etc., and facilitate driving in descending a slope by actuating and releasing an auxiliary brake and controlling its brake force based on the position of a transmission range, operation information of an accelerator pedal, operation information of a brake, etc.
CONSTITUTION: For a system where an auxiliary brake of an exhaust brake 7 is disposed in the middle of an exhaust tube 3 of an engine 1, with this exhaust brake 7 driven by an actuator 24, a transmission range changing switch 20 having range switches 21, 22 disposed in 2-range and L-range is disposed. An accelerator off switch 10 is disposed at an accelerator pedal 8, and an idle off switch 9 which becomes off for a rotation number of the engine 1 of less than idling is provided. For the actuator 24, the 2-range switch 21 or L-range switch 22 is connected with the accelerator off switch 10 and the idle off switch 9 serially.
HASHIMOTO HARUO
IWASAKI SHIGEKI
