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friction between the disc and the brake drum increases, because the main brake shoe to the secondary
brake shoe a much greater pressure than the brake pump pressure, so as to produce a lot of braking
force. Parking brake is mainly used in the parking state to prevent accidents caused by sliding slope.
The parking brake is equipped with a travel switch and the control circuit is disconnected during
parking. The parking brake must be released before the forklift starts to walk, and the control circuit
can be connected. Parking brake has the function of adjusting tension.
6.1brake pedal
Part of the brake pedal structure is shown in the figure. The pedal converts the stepping force acting on the pedal
to the brake oil pressure through the push rod of the brake master pump.
1
.Brake oil cup 2. Brake pedal 3. Brake pump 4.Brake support 5. Limit bolt 6. Brake sensor
6.2 brake master cylinder
The master pump consists of a seat, a one-way valve, a return spring, and a main leather
bowl, piston and auxiliary leather bowl. The end is fixed with a stop washer and a stop steel
wire, and the exterior is protected by a rubber dust cover. The piston of the master pump is
operated by the brake pedal through the push rod. When the brake pedal is pressed down, the
push rod pushes the piston forward, and the brake fluid in the pump body flows back to the oil
storage tank through the oil return port until the main rubber bowl blocks the oil return hole.
After the main leather bowl is pushed through the oil return port, the brake fluid in the front
cavity of the main pump is compressed and the one-way valve is opened, which flows to the
sub-pump through the brake pipeline. In this way, each sub-pump piston extends outward, so
that the brake shoe friction plate and the brake drum contact, to achieve the effect of
deceleration or braking. At this point, the piston back chamber is supplemented by brake fluid
from the oil return port and the oil intake port. When the brake pedal is released, the piston is
pressed back by the return spring, and the brake fluid in each brake sub-pump is also
