500 Nose Wheel Steering System Component Location
May 15/67 Figure 1 32-51-0
Page 3
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
Nose Wheel Steering Schematic 500
32-51-0 Figure 2 (Sheet 1) Nov 15/66
Page 4
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
500 Nose Wheel Steering Schematic
Nov 15/66 Figure 2 (Sheet 2) 32-51-0
Page 5
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
4. Rudder Pedal Steering Mechanism
A. The rudder pedal steering mechanism consists of a steering crank, a clutch arm, a cable drum, an eccentric mounted in the clutch crank, and a rudder pedal steering quadrant. (See figure 3.) This mechanism connects the rudder pedals to nose wheel steering and is actuated by the piston position system when the nose gear is compressed by airplane weight. This compression movement of the nose gear is transmitted by piston position linkage and cables to move the eccentric and reposition the clutch crank so that the stops, mounted on the clutch crank, do not contact the clutch arm. In this position, the clutch arm contacts the stops on the steering crank and any movement of the rudder pedals is transmitted from the steering crank to the rudder pedal steering quadrant. (See figure 4, condition 1.) This quadrant is connected to the nose wheel steering cables and is free to move with the cables whenever nose wheel steering is used, or drive the cables when positioned by the rudder pedal steering mechanism. (See figure 4, condition 2.) B. When the nose gear is extended, the piston position system positions the eccentric to move the stops mounted on the clutch crank into contact with the clutch arm. This prevents any movement of the rudder pedals from reaching the clutch arm and moving the quadrant. (See figure 4, condition 3.)
B. When the nose gear is extended, the piston position system positions the eccentric to move the stops mounted on the clutch crank into contact with the clutch arm. This prevents any movement of the rudder pedals from reaching the clutch arm and moving the quadrant. (See figure 4, condition 3.)
5. Steering System Cables
A. The nose wheel steering cable system consists of two sets of 3/32 inch diameter carbon steel cable with tin-coated corrosion-resisting steel terminals. The first set of cables is used to actuate the steering metering valve by turning the steering wheel and its two cables are designated NWSA and NWSB. The second set of cables makes up the piston position system to engage rudder pedal steering. Its two cables are designated NGPPA and NGPPB.
B. The steering cables, NWSA and NWSB, begin at the steering wheel drum and terminate on the steering collar at the back of the nose gear shock strut. Movement of the steering wheel puts one cable under tension and the steering control crank mounted on the nose gear is displaced moving the control piston in the steering metering valve. Movement of the control piston directs fluid under pressure to the steering cylinder which moves the steering collar. The steering collar moves in the desired direction of turn and as the amount of turn is reached, the tension in the cable is reduced by the follow-up action and the control piston is returned to the centered position. The wheel must be held throughout the turn or the system will return to center by action of the centering spring in the rudder pedal steering mechanism.
C. The piston position system cables, NGPPA and NGPPB, are driven by linkage connected to the torsion links. When the torsion links are compressed by nose gear action, the connecting linkage moves a quadrant and the NGPP cables reposition stops in the rudder pedal steering mechanism to allow rudder pedal steering.
500
32-51-0 Page 6 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. May 15/67
500 Rudder Pedal Steering Mechanism
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 起落架 LANDING GEAR(169)
