Speed Brake Hydraulic Schematic
Figure 5

T81262
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 27-62-00
 ALL  ú ú 01 Page 11 ú Mar 15/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
 C.  With the landing gear in the retracted position, the shock strut inner cylinder is fully extended. This positions the upper torsion link to cause the valve to block hydraulic pressure to the ground spoiler actuator up ports (Fig. 5).
 D.  With the landing gear in the extended position, the hydraulic pressure remains blocked until the airplane touches the ground and the right main landing gear shock strut is compressed. As the shock strut inner cylinder is compressed, the upper torsion link moves the push-pull cable to open the interlock valve. The interlock valve then connects hydraulic pressure from the ground spoiler control valve with the up ports of the ground spoiler actuators.
 8.  Ground Spoiler Actuator_______________________
 A.  All ground spoilers are positioned by actuators powered by hydraulic system A. The actuators used on ground spoilers 0, 1, 8, and 9 are identical as are ground spoiler 4 and 5 actuators. However, the actuators used on ground spoilers 0, 1, 8, and 9 are not identical with the actuators used on ground spoilers 4 and 5.
 B.  No. 0, 1, 8, and 9 Ground Spoiler Actuators.
 (1)  
The actuators are attached at the piston rod end to the spoiler and at the cylinder end to a support on the wing rear spar.

 (2)  
The actuator contains a locking mechanism which locks the actuator in the retract position (Fig. 4). The locking mechanism consists of a spring-loaded tapered locking piston and two locking segments or keys. When the actuator reaches the retract position, the spring-loaded piston is forced downward by hydraulic pressure. This forces the locking segments in a radial direction into a cavity whose diameter is slightly larger than the cylinder inside diameter, thus locking the actuator. If hydraulic pressure is lost, the spring will hold the piston in the locked position. Directing hydraulic pressure to cause reverse actuation provides a force on the piston greater than the spring force thus moving the piston inward. This allows the locking segments to move inward to unlock the actuator.

 (3)  
Swivel joints in the hydraulic lines allow the actuators to rotate as the spoilers raise.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 27-62-00
 ALL  ú ú 03 Page 12 ú Nov 15/88
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
 C.  No. 4 and 5 Ground Spoiler Actuators.
 (1)  
Two identical actuators and actuator linkages are used to position each ground spoiler. The actuators are attached at the cylinder end to a support on the wing rear spar. The actuator piston rod end is attached to the ground spoiler actuator linkage.

 (2)  
The actuators for ground spoilers 4 and 5 are similar to the actuators used on ground spoilers 0, 1, 8, and 9 except the locking mechanism locks the actuator in the extend position.

 9.  No. 4 and 5 Ground Spoiler Actuator Linkage___________________________________________
 A.  A ground spoiler actuator linkage connects each ground spoiler actuator to the ground spoiler (Fig. 2). The actuator linkage consists of an idler crank and pushrod. The idler crank is pivoted in the actuator support. The actuator piston rod end is attached to one end of the idler crank and the pushrod to the other end. The ground spoiler is attached to the end of the pushrod.
 B.  When the actuator is retracted, the idler crank pivots pushing the pushrod to move the ground spoiler to the raised position.
 10. Operation_________
 A.  The speed brakes are activated by moving the speed brake control lever aft. This is done manually or by the speed brake lever actuator (Fig. 2). Initially, the control lever must be raised to release the lever latch. As the lever is moved aft, lever motion is transferred through control rods to release the lever brake and rotate the speed brake forward drum. Cables from the forward drum transfer speed brake signals to the speed brake quadrant at the spoiler ratio changer. Motion of the speed brake quadrant operates the ratio changer. The speed brake quadrant transfers motion to the spoiler mixer, driving both mixer output drums in the spoiler up direction. This causes flight spoilers 2, 3, 6, and 7 to raise equally. The motion of the spoiler mixer positions the ground spoiler control valve.
　
中國航空網 www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：737-300 400 500 AMM 飛機維護手冊 飛行操縱 FLIGHT CONTROLS 5(78)