The reason why the brake effect of the brake disc is better than that of the drum brake
The brake disc of the disc brake is a round plate, which also rotates when the car is traveling.Brake calipers are used to clamp the brake discs in two pieces to produce braking force.Its relatively rotating brake disc is fixed.When the brake is pressed, it clamps the brake disc to slow down or stop.What are the reasons why the brake effect of the brake disc is better than that of the drum brake?
The braking power of the disc brake is weak. In fact, there is no large area of the drum brake. The natural braking efficiency is not as good as that of the drum brake. It's just that the drum brake has the biggest problem. Thermal recession and vigorous extreme braking will cause the brake drum to heat up, which will eventually cause the gap to become larger, the brake to become longer, and ultimately it will fail.However, drum brakes are low in cost and have high braking power, so trucks use drum brakes.
The rear wheels of many cars also have drum brakes, which are low in cost, and the power of the cars is small, and they are generally rarely used for extreme control, so the drum brakes on the rear wheels are very economical.However, since the front wheels of the car bear 75% of the force when braking, they are all front and rear drums.Including many rear-drive cars, the front and rear disc brakes are also larger in the front and smaller in the back.The front one is a hollow disc, the back one is a solid disc, and so on.
However, disc brakes have a gradual process. It is easy to control the braking force. Moreover, the brake discs come into contact with the air surface when they rotate with the wheels. There are few signs of thermal recession. Long-term braking can maintain a good braking effect. Some supercars use ceramic fiber brake discs before and after to avoid thermal recession.