Brake control method combining travel brake and auxiliary brake of towing vehicle

Abstract

The invention relates to a brake control method combining travel brake and auxiliary brake of a towing vehicle. The brake control method combining travel brake and auxiliary brake of the towing vehicle, disclosed by the invention, aims to solves the problems that under the condition that the auxiliary brake system of the towing vehicle is started, and a driver steps on a brake pedal, braking torque generated by auxiliary brake and travel brake is overlaid on the rear shaft of the vehicle, so that the distribution of vehicle braking force is un-uniform, and the rear shaft is locked or the vehicle sideslips; and the brake control method is used for realizing good dynamic distribution of braking force to avoid the phenomenon that the rear shaft is locked or the vehicle sideslips due to added braking force on the rear shaft of the towing vehicle. According to the brake control method disclosed by the invention, through the control of the slip rate, the vehicle brake stability is improved, the occurrence frequency of the phenomenon that the rear shaft is locked or the vehicle sideslips due to added braking force on the rear shaft of the towing vehicle is reduced, and the vehicle brake stability and the travelling safety are improved; and besides, through the reasonable utilization of the auxiliary brake system, the abrasion of vehicle tyres and friction plates is reduced, so that the transport efficiency is improved, and economic benefits are increased.

Description

technical field [0001] The invention belongs to the technical field of vehicle braking system control, and relates to a combined braking control method of service braking and auxiliary braking of a tractor. Background technique [0002] With the increase of road mileage in our country, the proportion of road transportation in the domestic transportation market is increasing. For vehicles transported on roads in mountainous areas, because there are many long downhill sections, continuous long-term braking will cause excessive brake shoe temperature, decreased braking torque, and vehicle braking attenuation. is also becoming more and more popular. [0003] Although the auxiliary braking system has the advantages of reducing long downhill braking attenuation, reducing tire wear, and saving costs, but due to the limited braking capacity of the auxiliary braking system itself, and the change of braking torque with the change of rotation speed / vehicle speed, etc., the current Mo...

AI Technical Summary

Problems solved by technology

However, the control accuracy of this integrated control method is low, and it is difficult to accurately control the braking intensity required by the driver when braking with small or medium intensity. When the brake pedal is activated by 25%, the retarder is 100% effective. This method is more likely to cause uneven distribution of vehicle braking force, excessive braking strength, severe braking pitch, and poor comfort

[0005] Chinese patent CN104044571A discloses a combined braking system and method for automobiles and trains. By installing a retarder on the trailer, the combined braking of the air pressure braking of the trailer and the retarder of the trailer is realized. When the vehicle speed exceeds 10km / h, the combined brake The braking system uses the retarder to brake first. When the braking force provided by the retarder is not enough to meet the demand, the actuator will make the retarder and the trailer brake at the same time. However, this invention only considers the state of the trailer and will slow down The braking force provided by the retarder is evenly distributed to each axle of the trailer, but for a tractor equipped with a retarder, the braking force provided by the retarder only acts on the driving wheels, so the control method in the above invention is not applicable at all on the tractor

[0006] To sum up, in the process of using the auxiliary brake, the driver depresses the brake pedal according to the actual driving conditions such as the vehicle speed is too fast, etc., and applies the service brake to the vehicle. The braking torque generated by the auxiliary brake and the service brake Superimposed on the rear axle of the vehicle, it will lead to uneven distribution of the braking force of the vehicle, causing the rear axle to lock or skid

Existing vehicles with matching auxiliary braking lack a key control method to make the auxiliary braking system work with the traditional service braking system to achieve good dynamic braking force distribution of the vehicle

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