What is an active disk? Let's learn about it.

　　What is an Active Disc? Let's learn about it.

　　Active disc, also known as disc brake, is named after its shape. The brake disc is made of alloy steel and is fixed to the wheel, rotating with it. The friction force of the disc brake is generated between the components connected to the fixed parts of the car and the two end faces of one or more brake discs. A disc brake where the friction material only covers a small part of the working surface of the brake disc is called a caliper disc brake; a disc brake where the friction material covers all working surfaces of the brake disc is called a full disc brake. The single disc single caliper disc brake is the most widely used brake in modern cars. Only a few large-tonnage mining dump trucks use single disc, three calipers, double disc, single caliper caliper disc brakes, as well as full disc brakes. Now most family cars use active discs, so what are its advantages and disadvantages, do you know?

　　Advantages of Active Disc:

　　1. The braking torque is independent of the front and rear movement of the car.

　　2. Good thermal stability. Due to the short size of the brake friction pads, the area of their working surface is only 12% ~ 6% of the brake disc area, thus having better heat dissipation.

　　3. The thermal expansion of the active disc does not cause a loss in the travel of the brake pedal like the thermal expansion of the brake drum, which also simplifies the design of the automatic gap adjustment device.

　　4. Good water stability. Due to the high unit pressure of the brake pads on the disc, it is easy to squeeze out moisture, and under the action of centrifugal force, it is easy to expel moisture. Additionally, due to the wiping effect of the brake pads on the disc, normal performance can only be restored after the first and second braking, while drum brakes can take more than ten brake applications to return to normal braking efficiency.

5. The wear of disc friction linings is easier to replace than that of drum friction linings, with a simpler structure and easier maintenance.

　　6. The gap between the active disc and the friction pad is small (0.05~0.15mm), shortening the working time of the oil cylinder piston, making it possible to increase the transmission ratio of the braking drive mechanism.

　　Disadvantages of Active Disc:

　　1. The manufacturing requirements for active discs are high, the wear of the friction pads is significant, and the cost is expensive.

　　2. Due to the small area of the friction pads, the relative working surface is also small, requiring high braking hydraulic pressure, which must be used by vehicles with power assist devices, generally using servo devices.

　　3. The braking is rough. Two friction pads with friction linings can slide back and forth on the splined shaft, which is a rotating part of the brake. During braking, the vehicle can stop in a very short time. Additionally, the angle of the ball groove on the pressure plate cannot be infinitely large, leading to unsmooth braking.

　　Today, disc brakes have been widely used in domestic vehicles, most of which are used on all wheels. A few are only used as front wheel brakes, paired with rear drum brakes. Moreover, new models and high-end models are gradually adopting disc brakes.