FLAP ACTUATOR(2 PLCS) C1
P
SLAT NO. 5
A
2(SH 1)
C1
A
P
SLAT NO. 6
3(SH 2)
VENT
4
STANDBY PRESSURE
P
(SH 2) (FULL EXTENSION)
INTERMEDIATEEXTENSION
C1 C2 A
C1 C2 LEADINGA
EDGE SLATACTUATORNORMAL LEADING EDGE DEVICES OPERATION IS
NOTE:
(3 PLCS) CONTROLLED BY THE TRAILING EDGE FLAP POSITION.
C1 C2
FULL EXTENSION A
AS THE TRAILING EDGE FLAPS LEAVE THE "UP" POSITION:A.
THE LEADING EDGE FLAPS WILL FULLY EXTEND
THE LEADING EDGE SLATS WILL PARTIALLY EXTEND
AS THE TRAILING EDGE FLAPS LEAVE THE "5" POSITION:B.
THE LEADING EDGE SLATS WILL FULLY EXTEND
THIS SEQUENCE IS REVERSED UPON RETRACTION.
Leading Edge Flap and Slat Control System Hydraulic Schematic
Figure 4 (Sheet 3)
3011R1-M683
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
27-81-00
ALL ú ú 02 Page 13 ú Nov 12/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
B. External ports in the actuator housing are provided for an actuator retract pressure line, two actuator extend pressure lines, and a standby system pressure line. The actuator retract pressure line provides pressurized fluid directly from hydraulic system B. The two actuator extend pressure lines provide system B pressurized fluid from the leading edge flap and slat control valve. With the hydraulic system pressurized, system B pressure is ported at all times to the retract side of both actuator pistons. System B hydraulic pressure from the control valve is directed to the slat actuator in two progressive steps. As the control valve moves to intermediate position, pressure is ported to extend the inner piston and rod assembly. This allows the actuator to move to the intermediate position. In the second step, the control valve ports hydraulic pressure to extend the outer piston while pressure is still ported to the inner piston. This allows the actuator to move to the fully extended position. Actuator extension results from system B pressure acting upon a larger area on the extend pressure side of the pistons than on the retract pressure side. When the control valve is returned to the intermediate position, the outer piston extend pressure is ported to system B return. Hydraulic pressure on the retract side of the outer piston then causes the outer piston to retract. When the control valve closes, the inner piston extend pressure is also ported to system B return. Hydraulic pressure on the retract side of the inner piston then causes the inner piston to retract.
C. During standby system operation, the actuator blocking valves port standby hydraulic pressure to the intermediate actuator piston and to the fully extend actuator piston. The actuator will remain in the extended position until system B hydraulic pressure is restored.
8. System B Hydraulic Fuse_______________________
A. One retract hydraulic fuse and one extend hydraulic fuse are installed in the leading edge flap and slat system B hydraulic pressure line (Fig. 4). The hydraulic fuses are located on the ceiling of the right wheel well. If an actuator failure or a line rupture occurs with system B hydraulic pressure applied, the fuses will close to prevent complete loss of system B hydraulic fluid. Each fuse will reset automatically when hydraulic pressure on both sides of fuse is equalized within 5 psi for five seconds.
9. Standby Hydraulic Fuse______________________
A. A hydraulic fuse is installed in the leading edge flap and slat standby hydraulic system pressure line (Fig. 1). The hydraulic fuse is located in the right wheel well, on the right side of the keel beam below the standby reservoir. If an actuator failure or a line rupture occurs with standby extend pressure applied, the fuse will close to prevent complete loss of standby system hydraulic fluid. The fuse will reset automatically when hydraulic pressure on both sides of the fuse is equalized within 5 psi for ten seconds.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
27-81-00
ALL ú ú 02 Page 14 ú Nov 12/01
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：737-300 400 500 AMM 飞机维护手册 飞行操纵 FLIGHT CONTROLS 6(17)
