How does the disc brake of an electric scooter exclude air? What should I do if the abnormal brake sound does not return?
The full name of a disc brake is a disc brake, which is composed of a brake disc connected to the wheel and a brake caliper on the edge of the disc. The principle of braking is that the high-pressure brake fluid pushes the brake pads to clamp the brake disc to produce a braking effect. Disc brake is also called disc brake. The disc brake disc pushes the brake caliper through the hydraulic pump to hold the brake disc tightly. In order to increase the braking force, according to the formula F=P*S, the method of increasing the braking area is generally used to increase the brake. Contact surfaces. PXID scooter design company can also extend the brake arm. There is also a way to increase the pressure by increasing the pressure of the hydraulic pump and increase the braking torque by increasing the diameter of the brake disc to increase the braking force.
How to exhaust air from disc brakes:
1. How to exhaust air and refuel: add enough oil to the oil storage cup and hold the brake handle repeatedly (5-6) times. Pinch it to the end without letting go, then loosen the oil drain bolt on the brake (remember to open the small rubber cap), let the brake fluid and air flow out, pay attention to the flow of liquid, tighten the bolt after feeling no air bubbles, and hold again Brake the handle until it feels strong and not let go. Loosen the oil drain bolt with the other hand to let the oil and air spray out together, then tighten the oil drain bolt, and then put the hand holding the brake handle (the order cannot be reversed), repeat several times until the air is released. (The pressure and non-disconnected bubbles from the brake fluid are exhausted). Note: It should be noted that the brake fluid level in the oil storage cup cannot be too low.
2. Abnormal brake sound. The normal hydraulic disc brake system also has a slight friction sound, but if the sound is louder, it means there is a fault, usually caused by the following reasons:
The brake pads are severely worn and the friction pads have worn out. The friction between the metal pads and the brake disc will produce a "rubbing" and "rubbing" sound. The brake pads should be replaced. The brake disc is not flat, the brake disc has been impacted, and there are warped parts, which will swing during the rotation, rub the brake pads, and cause noise. It can be confirmed by rotating the wheel to observe the swing of the brake disc. If the swing exceeds 0.5mm, the brake disc should be replaced. Missing or lack of elasticity of the shrapnel will cause the brake pads to hit back and forth in the slot and produce noise. The shrapnel can be supplemented or modified for processing. If the brake does not return, there will be a loud rubbing sound. You can install the brake not return to deal with the fault. Heat dissipation and optimize thermal attenuation.
3. The brake does not return. After releasing the brake lever, it is still very difficult to turn the wheel, which may be caused by the following reasons:
The plunger of the upper pump does not return to the position, which is caused by the expansion of the sealing ring or the corrosion of the plunger and the plunger hole. The upper pump assembly should be replaced. The joint between the brake lever and the plunger is too tight, the plunger cannot be completely returned, the liquid cannot flow back, and it is always in the braking state. It is usually caused by the improper replacement of the brake lever. You can polish the joint between the brake lever and the plunger. The brake hose is blocked, the liquid return is blocked or the piston of the lower pump is severely rusted, and it is not suitable to return to the position if it is too tight. The brake oil pipe can be replaced or the piston of the lower pump can be removed for lubrication and cleaning. The lower pump body and the pump body bracket are rusty, and the pump body cannot move axially along the bracket. Under normal circumstances, there is a slight amount of movement between the pump body and the bracket. In this case, rust removal and lubrication can be done after the pump body and bracket are disassembled.
4. The rear wheel locks up. In this case, you need to open the lower pump to exhaust air and check the oil outflow. If the oil is sprayed out after opening, and the rear wheel becomes lighter, it means that there is a pressure problem, and the fault may occur in the upper pump and the oil pipe; If the oil slowly flows out after opening, and the rear wheel is still heavy, it means that there is a mechanical problem with the lower pump. The brake is not working or there is no brake. The reason for this failure is insufficient brake fluid or gas in the pump. You need to add brake fluid or deflate appropriately according to the specific reason (deflation method: loosen the deflation screw, slowly tighten the brake lever, and you can see at the same time Bubbles emerge from the vent hole, then first tighten the bleed screw, then loosen the brake lever, and repeat until there are no bubbles.
PXID scooter design company reminds the need to pay attention to: deflation also needs to be done at the screw at the connection between the upper pump and the brake hose. In individual cases, the mixed and added brake fluid will generate gases and compounds during the vehicle placement process. The compounds will easily block the small oil inlet holes in the oil pool. Only when the small holes are dredged with fine steel wires can the venting work be carried out effectively.
Disc brake maintenance
Check whether the brake fluid leaks. If it leaks, please clean the leaked brake fluid and go to the repair shop to find out the cause and repair it in time. Check whether there is mud and sand at the brake caliper. If there is, it should be cleaned up to prevent the mud and sand from causing the brake cylinder and friction plate to not return, which will affect the braking effect and the life of the brake system. Change the brake fluid regularly. Regularly check at the maintenance station to determine whether the brake fluid level is below the minimum score line, and check the wear conditions of the friction linings and brake discs.