Everyone should understand the brakes. In fact, the brakes are simply brakes, and brakes are needed in all models. So who knows what the general principle of brakes is?

　　Let me introduce to you the working principle of general brakes, I hope it will be helpful to you.

　　The general operating principle of the brake system is to use the conflict between the non-rotating elements connected to the body (or frame) and the rotating elements connected to the wheels (or drive shafts) to hinder the transformation or the tendency of the wheels.

　　A simple schematic diagram of the hydraulic brake system can be used to clarify the working principle of the brake system. A metal brake drum with the inner circular surface as the working surface is fixed on the wheel hub and rotates with the wheel. On the fixed brake base plate, there are two supporting pins supporting the lower ends of the two curved brake shoes. The outer circular surface of the brake shoe is equipped with a conflict sheet. The brake bottom plate is also equipped with a hydraulic brake wheel cylinder, and an oil pipe 5 is used to communicate with the hydraulic brake master cylinder installed on the frame. The piston 3 in the master cylinder can be operated by the driver through the brake pedal organization.

　　When the driver steps on the brake pedal to make the piston squeeze the brake fluid, the wheel cylinder piston presses the brake shoe against the brake drum under the effect of hydraulic pressure, so that the brake drum reduces the transition speed or stays still.

　　All necessary resistance moments required to stop or decelerate mechanical working parts are called braking torques. Braking torque is the basis for describing and selecting brakes, and its size is determined by the type of machinery and operating requirements. The function of the conflicting data (brake parts) used on the brake directly affects the braking process, and the main factors affecting its function are the operating temperature and the temperature rise speed. Conflict data should have a high and stable conflict coefficient and outstanding abrasion resistance. Conflict data is divided into two types: metal and non-metal. The former are commonly used for conflict materials such as cast iron, steel, bronze and powder metallurgy, and the latter are leather, rubber, wood and asbestos.

　　When you know the brake system of a certain model, you can often hear the words "front disc and rear drum" or "front disc and rear drum". So, what does it mean? Recently, readers have emailed Ask questions about automobile braking systems, such as the difference between disc brakes and drum brakes, the difference between ventilated discs and solid discs, and so on.

　　In the current auto market, many low- and mid-range models with smaller engine displacements mostly use "front disc and rear drum" braking systems, that is, disc brakes are used for the front wheels and drum brakes for the rear wheels. For example, the common FAW-Volkswagen Jetta, Changan Suzuki Alto and Antelope, BYD Flyer, Chunfeng Yueda Kia Maxima, Shanghai GM Sail and so on. Let's first briefly understand the drum brakes that are often used for rear wheels.

　　The practical application is different. Disc brakes are better than drum brakes. The asbestos material in the brake drum can cause cancer. Drum brakes and disc brakes have their pros and cons. In terms of braking effect, there is not much difference between drum brakes and disc brakes, because when braking, the conflict between the tires and the ground makes the car stop gradually. If the body is slender and light in weight, the use of drum brakes on the rear wheels is enough to make the tires and the ground meet the conflict force. If the rear wheels use disc brakes, the ABS and EBD systems will also actively reduce their braking force to ensure that the rear wheels will not lose grip and present the appearance of slipping and locking.

　　In terms of heat dissipation, disc brakes dissipate heat faster than drum brakes, and ventilated disc brakes have a very good heat dissipation effect; in terms of flexibility, disc brakes will be higher, but in the next rainy day when the road is muddy when the brake disc is stained with mud and sand The braking effect will be greatly reduced. This is also a defect of disc brakes; in terms of cost, drum brakes are lower than disc brakes and have a longer service life. Therefore, some mid-to-low-end cars will use drum brakes. Roulette brake.

　　Car designers set off from an economical and useful point of view. Usually cars choose a hybrid approach, front-wheel disc brakes and rear-wheel drum brakes. In the braking process of a four-wheeled car, due to the effect of inertia, the load of the front wheels usually accounts for 70%-80% of the total load of the car, so the front wheel braking force is greater than the rear wheel. In order to save costs, car manufacturers choose front-wheel disc brakes and rear-wheel drum brakes. For mid- and high-end cars with four-wheel disc brakes, the front-wheel ventilated disc brakes are used for excellent heat dissipation, and the non-ventilated disc brakes for the rear wheels are also the reason for the cost. After all, the production technology of the ventilated pan is much more messy, and the price is relatively expensive. With the development of data science and the decline of costs, in the field of cars, disc brakes have a tendency to gradually replace drum brakes.

　　Generally, the brake applies a braking torque to the rotating element through a fixed element in between, so that the rotation angular velocity of the latter is reduced. Together with the adhesion effect of the wheel and the ground, the braking force of the road facing the wheel is generated to slow the car. Any brake that generates a braking torque due to the conflict between the fixed element and the rotating element's work appearance becomes a conflict brake. The current conflict brakes used in automobiles can be divided into two categories: drum type and disc type.

　　The rotating element is fixed on the wheel or the axle shaft, that is, the brake that directly separates the effect of the braking torque on the wheels on both sides is called the wheel brake. The rotating element is fixed on the drive shaft of the drive train, and its braking torque is redistributed to the two wheels through the drive axle. The brake is called the center brake.

　　After reading the above introduction, do you have a deeper understanding of brakes?