The question of how long the trailer needs to brake before the main vehicle is actually about the consistency of the main suspension in the braking of the vehicle. It simply is not accurate to emphasize the need of the trailer braking as early as the main car.

We know that when the tractor driver is braking the vehicle, the initial speed of the main vehicle and the trailer is the same, but the trailer and the main vehicle are connected by saddle or by decoupling. Finally, the speed of the vehicle is decided by the reduction of speed, and the speed ratio is reduced to provide ground reaction force and the braking quality; if the trailer trailer braking torque deceleration and the main vehicle deceleration is not consistent, so the main trailer and the driving speed of the vehicle will not, by the end of saddle or hook to provide a consistent force to keep the speed of the main vehicle and the trailer.

When the trailer is faster than that of the main vehicle, trailer will impact the main vehicle, while the impact force received by the saddle and the hook is very difficult to ensure the effect on the longitudinal plane of the vehicle, if the impact is too large, especially in the snow the low adhesion road, the main Trailer is prone to folding phenomenon. Similarly, if the brakes need to be braked in the course of steering (e.g., emergency avoidance), the impact is more likely to occur if the consistency of the main suspension is poor. Braking on a road with low adhesion on a straight road, although it will cause a spin moment on the main vehicle, will not collapse due to the speed of the main vehicle being faster than that of the trailer. However, when braking in the steering process, if the main hang consistency is not good, the towing force of the trailer on the main vehicle will lead to understeer of the vehicle.

The ideal situation is to ensure that Baotou North Benz accessories main vehicle and the trailer brake deceleration in time so as to ensure consistent on braking process speed, so it will not in the saddle or hook impact or drag force; however, in the practical application, the adhesion coefficient of main Trailer road load different, and Baotou North Benz car accessories factory is the main host production trailers, and unpredictable user will use the trailer braking force distribution and power, so it is difficult to ensure the consistency of the speed reduction main trailer braking; and from the analysis of the above two conditions of and second kinds of situation is better than the first one, so we will try to avoid the first case in the design of vehicle brake. The usual way is to give the trailer an early brake. The amount of this advance also need to ensure that the towing force of the trailer is within a reasonable range, otherwise it will have a great impact on the main hanging link. Of course, now the trailer brake valve also has a lead amount, but this advance is mainly due to the length of the pipeline and valve response time caused by the delay of the problem. But in the unpredictable Trailer configuration, Baotou North Benz accessories main car manufacturers is not suitable to consider hanging trailer braking advance, and should be considered only to guarantee the elimination of braking due to the length of the pipe and valve response time delay problem. But the trailer braking advance quantity is designed by the trailer manufacturer, and the matching is more reasonable