A320飞机维护手册 AMM LANDING GEAR 起落架7(55)

曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

 The pressure output from the DDV goes through its related shuttle valve to isolate the pressure in the service line from the parking brake. The safety valve in the manifold acts as an hydraulic fuse. If a large leak occurs downstream of the safety valve, it closes to stop the flow for each pair of brakes. The pressure transducer measures the pressure that goes to the brakes and sends the data to the BSCU, ABCU and the Triple Pressure Indicator. This lets the BSCU know if the operation of the applicable DDV is correct.
 The alternate brake system connects to one of the two sets of pistons in each brake. The other set of pistons connect to the Normal brake system. A half-coupling connects each brake service line to a half-coupling on the brake. Each half-coupling seals automatically when disconnected to prevent a decrease of system fluid and/or fluid contamination.
 The alternate HP manifold provides the interface between the alternate braking system and the parking brake system.
 A tachometer is installed in each axle of the main landing gears to measure the speed of the wheel and send the data to the BSCU. The BSCU uses this data to compute the antiskid current given to the ABCU.
 1EFF : 401-499, 1 32-43-00Page 5 1 1 Config-2 Aug 01/05 1 1 1CES 1

 4. Power Supply
____________
 A. Electrical Power Supply
 (Ref. Fig. 002)

 B. Hydraulic Power Supply
 The hydraulic pressure is supplied from the Yellow Main Hydraulic Power system (Ref. 29-13-00).
 1EFF : 401-499, 1 32-43-00Page 6 1 1 Config-2 Aug 01/05 1 1 1CES 1

 Power Supplies - Schematic
 Figure 002

 1EFF : 401-499, 1 32-43-00Page 7 1 1 Config-2 Aug 01/05 1 1 1CES 1

 5. Interface_________ (Ref. Fig. 003)

 1EFF : 401-499, 1 32-43-00Page 8 1 1 Config-2 Aug 01/05 1 1 1CES 1

 Alternate Braking with Anti Skid system - Interface
 Figure 003

 1EFF : 401-499, 1 32-43-00Page 9 1 1 Config-2 Aug 01/05 1 1 1CES 1

 6. Component Description_____________________
 A. Alternate Brake Manifold Assembly (2852GM, 2853GM)
 (Ref. Fig. 004)
 The manifold assembly is installed in the wing shroud box.The primary component parts of the manifold assembly are:
 -an alternate brake manifold
 -three filters
 -
a check valve

 -
a shuttle valve

 -
a safety valve

 -
a direct drive valve (DDV)

 -
a pressure transducer

 (1) Manifold
 (Ref. Fig. 004)
 The manifold has four ports which have union type connectors:
 -two supply ports A and D
 - one service port B
 - one return port C.

 The manifold has internal bores that contain:
 -
the two inlet filters

 -
the shuttle valve

 -
the safety valve

 -
the check valve

 -
the filter at the service port.

 It also has external faces for the DDV and the pressure transducer. The filter protect the components installed in and on the manifold. A sealed plug keeps the filter in position.
 (2) Shuttle valve
 (Ref. Fig. 005)
 The shuttle valve isolates the parking brake supply from the alternate brake supply.
 1EFF : 401-499, 1 32-43-00Page 10 1 1 Config-2 Aug 01/05 1 1 1CES 1

 Alternate Braking Manifold Assembly
 Figure 004

 1EFF : 401-499, 1 32-43-00Page 11 1 1 Config-2 Aug 01/05 1 1 1CES 1

 Shuttle Valve - Alternate Braking Manifold
 Figure 005

 1EFF : 401-499, 1 32-43-00Page 12 1 1 Config-2 Aug 01/05 1 1 1CES 1 The shuttle valve has a body that is installed in the manifold block. The body holds a valve and a spring. An end plug keeps these items in the body and supplies a seat for the valve. Usually the spring keeps the valve against the seat to let the alternate brake hydraulic supply go through to the related brakes. When the parking brake is set, the parking brake hydraulic supply moves the valve against the spring. This lets the parking brake supply go through to the related brakes and isolates the alternate brake supply.

 (3) Safety valves
 (Ref. Fig. 006)
 If a large leak occurs downstream of the safety valve, the valve closes to stop the flow of the hydraulic fluid to its related brakes. The safety valve has a valve, a spring and a plug. The plug holds the valve and the spring in the manifold, the spring keeps the valve off the valve seat. A flange around the valve has holes through it to let the hydraulic fluid go through to the brakes.
 When the fluid goes through the safety valve, the pressure at the rear of the flange (and in chamber X) moves the valve nearer the seat. This movement stops when the pressure in chamber X and the valve seat are equal. If a leak occurs downstream of the valve, the pressure at the valve seat decreases. This lets the pressure in chamber X move the valve against the seat to close the valve. The pressure in chamber X will keep the valve in the closed position until the plug is removed sufficient to release it. When this occurs the spring moves the valve back to its initial position.
　
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：A320飞机维护手册 AMM LANDING GEAR 起落架7(55)