-
The carbon heat sink stack (rotors and stators)
-
The torque plate.
C.
The aluminum piston housing contains seven adjuster/piston assemblies, a pressure port and a bleeder port. Twelve bolts at equal distances around the brake attach the piston housing to the torque plate. The piston housing connects to the hydraulic system at the pressure port. The piston housing assembly, with its components, operates the brake by moving the pistons in and out and by doing automatic clearance adjustments.
(1)
The piston assemblies move out from the brake piston housing when hydraulic pressure is applied. This compresses the heat stack against the torque plate of the brake to supply braking friction.
(2)
The torque arm on the carrier connects to one end of a brake equalizer rod. The other end of the rod connects to the base of the shock strut. This prevents the brake from turning on the axle when the heat stack is compressed.
(3)
Automatic clearance adjustments are done by automatic adjuster assemblies inside each piston assembly. Each adjuster assembly contains a spring which pushes the piston back to its original position when hydraulic pressure is released. It also contains a tube and ball assembly which keeps the distance between the piston and the pressure plate constant as the brake heat stack wears.
(4)
The bleeder valve in brake piston housing is used to bleed fluid from the brake and hydraulic lines during maintenance.
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(5)
Two wear indicator pins attach to the pressure plate. They move through a bracket attached to the piston housing. This gives a visual indication of carbon wear in the heat stack.
D.
The carbon composite heat stack contains all the components that have friction surfaces, which when compressed together, cause the wheel to decrease its speed. These components are the pressure plate, four rotor disks and five stator disks.
(1)
The rotors are connected to the wheel through the rotor drive keys in the wheel thus turn with the wheel. The stators, one on each side of each rotor, are connected to the torque tube and do not turn. Braking friction is caused when the rotors are compressed against the stators.
E.
The end plate contains a torque tube that attaches to the piston housing. This holds the heat stack between the piston housing and the end plate. The torque tube contains splines which mate with slots on the inside diameter of the stators in the heat stack. This permits the stators to move along the torque tube but not to turn. A heat shield between the piston housing and the pressure plate protects the piston housing from heat from the heat stack. Heat shields installed on the inside diameter of the torque tube protect the axle and axle sleeve.
F.
You can remove and install the brake using procedures in this section. You can also inspect the brake for wear or damage. The Hydraulic Brake System Adjustment Test (AMM 32-41-00/501) makes sure the brakes are operating correctly. All brake adjustments and repairs are done during shop overhaul.
12. Hydraulic-Pressure-Surge Accumulators (Fig. 7)
_____________________________________
A. The hydraulic-pressure surge accumulators absorb sudden pressure
increases from brake return flow to permit faster brake release.
B. The wing-gear-hydraulic pressure surge accumulators are on the rear spar of the wing above the wing gear trunion. One accumulator is used for each wing gear. One hydraulic-pressure-surge accumulator is used for the brakes on the two body gears. It is on the inboard bulkhead of the right-body-gear wheel well.
C. The hydraulic-pressure-surge accumulators operate the same as the hydraulic brake accumulator.
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HYRDRAULIC-PRESSURE- 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：747-400 AMM 飞机维护手册 起落架 LANDING GEAR 6(22)
