The Vehicles Travels In The Downhill Road Union Brake Characteristic Research

When vehicle travels in the downhill path mountain road, only use the main brake is not meet requirements of the continuous brake. So as a continuous brake, it is indispensable for a vehicle travels in mountain area to use engine brake and exhaust brake. In this paper, the author make an in-depth study on the brake characteristics of engine brake or exhaust brake with main brake affect together when vehicle travels in the downhill road.First, the text identified research model vehicles after lots of survey,then test the model vehicles on-road, and work out brake characteristics of vehicle engine brake and exhaust brake in every situation. Second,based on the analysis of characteristics of engine brake and exhaust brake ,the author determine their downhill capacity and the ability of energy absorption characteristics, indicate that only use assisted brake is hard to meet brake requirements in downhill road,too. Therefore, by studying the relationship model between the temperature rise and energy of the main brake on the downhill road, the author analysis the energy absorption relationship between main brake and assisted brake in the course of the brake affect together. Furthermore,a relationship model on downhill slope, length and speed with the brakes was set up when brake affect together. With the relationship model, several different conditions on different loading of vehicles are simulated, analysis and compared, the result is that main brake braking performance constant is improved when using main brake and assisted brake affect together.The results of the research play a practical significance role on safety in continuous downhill in China's mountain area.