1.1 DevelopmentStatus of Automotive Braking System at Home and Abroad

At present, almostall automobiles use friction brakes, which can be divided into drum brakes anddisc brakes. Among them, disc brake is widely used because of its good heatdissipation and better braking efficiency, but because disc brake is moreexpensive than drum brake, it still uses front and rear drum brake on somelow-end vehicles. In fact, the brake of automobile is an energy conversion waythat converts kinetic energy generated in the course of driving into heatenergy. Therefore, if a high-speed vehicle runs at high speed Frequent use ofbrakes will make the brake friction time too long to generate too much heat intime to dissipate heat, the braking efficiency will be greatly reduced,affecting the braking efficiency, the braking performance of thermalattenuation phenomenon.

With thedevelopment of China's automotive industry technology, the introduction ofjoint ventures, foreign advanced technology into the Chinese market, automotivedisc brakes have begun to appear in China. The cover of disc brake has played agreat role in improving vehicle performance, ensuring safety and improvingrider's comfort. According to the latest statistics, drum brakes account foronly 20% of the brakes in passenger cars in China, and disc brakes are used infront wheel brakes. At present, the application of disc brake in our country isgrowing very fast, and more and more enterprises related to disc brake in ourcountry. In foreign countries, due to the early research of foreign automobileindustry, the technology of producing gas (liquid) pressure disc brake isrelatively mature in the course of decades of development. Bosch, Avenmeichiand other companies produce 20-500,000 units a year; in developed countriessuch as Europe and the United States, disc brakes have been equipped as astandard spare parts in various types of vehicles. As a big automobile salesand production country, with the influx of Japanese and European automobiles,the trend of developing pneumatic disc brakes is getting hotter and hotter. Inthe next few years, with the improvement of traffic conditions, the increase ofvehicles, the implementation of new regulations, the application of disc brakeswill be more and more extensive, and the development prospects will be betterand better.

1.2 TheSignificance and Significance of Selecting Topics

The function of automobilebraking system is to decelerate the vehicle at a proper deceleration until itstops; to keep the vehicle at a constant speed when driving downhill; and tokeep the car stable when parking on the roadside. The driving safety ofautomobile is closely related to the braking system of automobile. Therefore,the performances of the actuator and the control mechanism of the brakingsystem must be taken into account in the design of automobile, so as to designthe braking system of automobile and meet the requirements of automobilesafety. At the same time, the quality of the braking system directly affectsthe running condition and transportation efficiency of the vehicle, and thelevel of transportation efficiency affects the economic benefits of the traveller.It can be seen that the design of brake system is an important link inautomobile design.

The design ofautomobile braking system can determine the safety, comfort, economy and othercharacteristics of a car. It is very important for automobile design to knowthe structure type of automobile brake and master the correct method and stepsof parameter selection.

Through the designof braking system, we can not only broaden our vision and knowledge, but alsocultivate a serious and realistic learning attitude and strengthen theconnection between theory and practice.

2. 研究的基本内容与方案

2.2Main Contents