In the case of pneumatic caliper disc brakes, oil is hydraulically injected into the inner and outer wheel cylinders. Under the action of hydraulic pressure, the piston can press the brake block against the brake disc, thereby generating frictional torque and braking. And what is its main working principle?
When the brake is released, the piston and brake pads return to position by the elastic force of the sealing ring and the elastic force of the spring. Since the deformation of the edge of the rectangular sealing ring is very small, the gap between the friction plate and the disc is only about 0.1mm on each side when it is not braking, which is sufficient to ensure the release of the brake. And because the thickness of the brake disc changes only slightly when it is heated and expanded, the phenomenon of "holding up" will not occur. In addition to the sealing function, the rectangular rubber sealing ring also plays the role of piston return and automatic clearance adjustment. If the gap between the friction lining of the brake block and the disc increases, after the deformation of the seal ring reaches the limit during braking, the piston can continue to move until the friction lining presses the brake disc. After the brake is released, the distance that the rectangular rubber seal pushes the piston back is the same as before wear, and still maintains the standard value.
Generally, there is no friction assisting effect, so the brake performance is less affected by the friction coefficient, that is, the performance is more stable; the performance decreases less after immersion in water, and it can be restored to normal after only one or two braking; the output braking torque is the same In the case of, the size and mass are generally small; the thermal expansion of the brake disc along the thickness direction is extremely small, and it will not increase the brake clearance significantly like the thermal expansion of the brake drum and cause the brake pedal stroke to be too large; the clearance is easier to achieve Automatic adjustment, other maintenance and repair operations are also relatively simple.
