Why do they say disc brakes are better?

Disc brakes, also known as disc brakes, are taken from their shape as the name suggests. The brake discs are made of alloy steel and are fixed to the wheels, which rotate with them. Disc brakes are now used in most family cars. Do you know the advantages and disadvantages of disc brakes?

Advantages of disc brakes:

1. Braking torque is independent of the forward and backward operation of the car.

2. Good thermal stability. Because the size of the brake friction pad is not long, its working surface area is only 12% ~ 6% of the area of the brake disc, so the heat dissipation effect is better.

3. The thermal expansion of the brake disc will not cause the loss of travel of the brake pedal like the thermal expansion of the brake drum, which also simplifies the design of the automatic clearance adjustment device.

4. Good water stability. Due to the high pressure of the brake pads on the disc unit, it is easy to squeeze out the water, and it is also easy to discharge under the action of centrifugal force after contacting the water, coupled with the erasing effect of the liner on the disc type, therefore, the water can only return to normal after one and two braking, while the drum brake needs to go through more than a dozen braking times to restore the normal braking efficiency.

5. The disc friction liner is easier to replace than the drum friction liner after wear, and the structure is also simple and easy to maintain.

6. The gap between the brake disc and the friction lining is small (0.05 ~ 0.15mm), which shortens the working time of the cylinder piston and increases the force transmission ratio of the brake drive mechanism.

Disadvantages of disc brakes

1. The manufacturing requirements of brakes and brake pipes are high, the friction loss is large, and the cost is expensive.

2. Due to the small area of the friction plate, the friction force relative to the working face is also small, and high braking hydraulic pressure is required, and there must be a booster device to use the vehicle, and the servo device is generally used.

3. The brakes are rough. Two friction discs with friction pads can slide back and forth on the splined shaft, which is the rotating part of the brake. When braking, the vehicle can be stopped in a very short time. In addition, the inclination angle of the ball groove on the pressure plate cannot be infinite, so the brake is not smooth.

Nowadays, disc brakes are widely used in domestic vehicles, most of which are wheels; A few use only front brakes and rear drum brakes. In addition, disc brakes are gradually being adopted by new and high-end models.