| 摘要 |
PROBLEM TO BE SOLVED: To provide a hill start assisting device capable of releasing brake holding accompanying a stop on an ascending slope at appropriate timing based on a road surface gradient estimated by detection means included in a tractor side without disposing detection means such as an acceleration sensor on a trailer side.SOLUTION: When a tractor side enters an ascending slope during traveling of a trailer vehicle and an estimated road surface gradient &thetas; is equal to or more than a downside determination value &thetas;21 (YES in S10) or equal to or more than a downside determination value &thetas;32 (YES in S16), a first speed or a second speed which is a slope shift stage is selected as a start stage (S12 and S18). When a tractor side enters a flat road, a road surface gradient &thetas; is less than an upside determination value &thetas;23 (YES in S20), and the tractor side travels by a movement determination value L0 (YES in S26), a third speed is selected as a start stage (S28). On both the ascending road and the flat road, braking of the trailer vehicle is held during a stop, and released during a start. Brake release timing is set according to the start stage (S13 and S19). |
