737 AMM 飞机维护手册 EXHAUST(11)

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

C.  Thrust Reverser Lock
(1)  The thrust reverser lock assembly maintains the thrust reverser locked in the forward thrust position except when reverse thrust operation is selected. Two locks are used on each reverser, one for each deflector door. (See figure 1.) The doors are held in the forward thrust position by overcentering of the door linkage and by engagement of the door locks. Door lock torsion springs hold the latches in the lock position. When reverse thrust is selected, the lock actuators are pressure-sequenced to unlock the door latches before the door actuators are pressurized. As the doors move to reverse thrust, the latch blocking arms rotate to block the latches in the unlock position. When forward thrust is selected, pressure applied to the actuator lock ports extends the actuators but the latches remain unlocked until the doors are stowed and the blocking arms are depressed. With the latch blocking arms held down by the stowed doors, the latches are driven to the lock position by the door lock torsion springs.
500 
78-32-101 Page 4  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  Nov 15/70 

D.  Thrust Reverser Fairings
(1)  The thrust reverser fairings consist of a deflector door fairing, tailpipe fairings, fixed fairing, and actuator housing fairings. (See figure 1.) The deflector door fairing is attached to the upper deflector door and can be adjusted to fair with the aft fairing. The deflector door fairing is not part of the deflector door assembly. The tailpipe fairings and fixed fairing are used to form the external cowling around the tailpipe extension. The fixed fairing is attached to the tailpipe extension and to the engine shroud, and covers the upper part of the tailpipe extension. The tailpipe fairings are hinged to the fixed fairing, and cover the rest of the tailpipe extension. The actuator housing fairings cover the thrust reverser actuators. There are two actuator housing fairings on each reverser. All fairings are provided to form an aerodynamically smooth surface, and to protect the thrust reverser components.
E.  Thrust Reverser Linkage
(1)  
The thrust reverser linkage assembly is a four-bar linkage system used to stow and deploy the thrust reverser deflector doors. The linkage assembly is powered by the hydraulically operated thrust reverser actuators. The linkage assembly consists of a driver link, idler link, and an overcenter link, with the driver link attached to the forward part of the deflector door, and the idler link attached to the aft part. In addition, there is a guide carriage and two guide rods. (See figure 1.) The driver links are attached to the guide carriage through the overcenter links. This system maintains a positive closed-door position when the deflector doors are in the forward thrust position.

(2)  
The LH and RH linkage assemblies are identical except for the feedback control mechanism. The feedback control rod is attached to the lower LH guide carriage and is used to mechanically transmit the position of the guide carriage to the power control interlock mechanism. For a description of the feedback control, refer to 78-34-01.

F.  Tailpipe Extension
(1)  The tailpipe extension is attached to the aft part of the engine and the forward part of the thrust reverser assembly. The tailpipe is tapered so as to direct exhaust gases for the proper thrust during forward thrust operation.
500 
Feb 15/69  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  78-32-101 Page 5 

3.  Operation
A.  The thrust reverser operation is controlled by a thrust reverser control system which is manually operated by manipulation of the reverse thrust lever. The actuating medium is pressurized hydraulic fluid supplied by the aircraft landing gear down line portion of the A hydraulic system.
B.  When reverse thrust operation is selected, with the pressure port on the thrust reverser control valve pressurized, the deploy port on the control valve opens and supplies pressure to the unlock port on the lock actuator, and the deploy port on the thrust reverser actuator. Since less pressure (95 [+ 45] psig) is required to move the lock actuator piston than is required to move the thrust reverser actuator piston due to the overcenter linkage, the lock actuator piston retracts to the unlock position first. When sufficient pressure (625 [+ 195] psig) builds up at the thrust reverser actuator, the actuator piston retracts causing the guide carriage to move forward and the doors to open.
C.  When forward thrust operation is selected, with the return port on the control valve pressurized, the stow port on the control valve opens, supplying pressure to the lock port on the lock actuator, and the stow port on the thrust reverser actuator. The lock actuator piston extends and positions the lock latch to the closed position. The thrust reverser actuator piston then extends, moving the guide carriage aft and closes the deflector doors. The deflector door mechanically snaps the lock latch into the locked position.
　
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：737 AMM 飞机维护手册 EXHAUST(11)