(5)
The cable loop is protected from high input forces from the pilot by a torque limiter that limits tiller lever input to 40 pounds maximum. The torque limiter transmits torque through spring loaded rollers that engage a cam mounted to the forward cable drum. See Fig. 3 torque limiter schematic. If the system cable load exceeds the torque limit, the rollers will come out of the detents in the cam. The rollers will only re-engage when the tiller is restored to its proper relationship with the forward cable drum.
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SEE A
SEE A SEE D SEE A
SEE B SEE C
1 2
TILLER HANDLE
TILLER HANDLE A
INDICATOR INDICATOR
GEARBOX
A COUPLING
SIDEWALL CONSOLE (REF) GEARBOX
2 1 (2 LOCATIONS ON TILLER AND GEARBOX GUN 051 ALL EXCEPT GUN 051 ) A 2 COUPLING A-A
Tiller, Gearbox, Torque Limiter Mechanism Figure 3 (Sheet 1)
D00711
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NWSA
NWSB
QUADRANT AND LOAD LIMITER B
INDEX SPRING PIN
(2 DETENTS 180` APART)
INBD
FWD
TILLER INPUT (40 POUNDS MAX. TILLER DISCONNECT FORCE)
(2 ROLLERS 180` APART)
NOSE WHEEL STEERING CABLES TO CONTROL VALVE
TORQUE LIMITER SCHEMATIC
Tiller, Gearbox and Torque Limiter Mechanism Figure 3 (Sheet 2)
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(6)
GUN 051; The first officer's tiller (Details A, B and C; Fig. 3) is similar to the captain's tiller except a torque limiter is not installed on the tiller shaft. The first officer's tiller is connected by a separate cable loop in parallel with the captains tiller and transmits motion to the main steering system cable loop through the captain's tiller torque limiter.
C.
Rudder Pedal Steering Interconnect Mechanism (Fig. 4)
____________________________________________
(1)
The rudder pedal steering interconnect mechanism consists of a rudder pedal steering crank, a clutch arm, a cable drum, an eccentric arm and a rudder pedal steering quadrant.
(2)
This mechanism connects the rudder pedals to the nose wheel steering system and is engaged by the piston position system when the nose gear is compressed. Conversely it is disengaged when the nose gear shock strut is extended at lift off.
(3)
The nose gear shock strut compression movement is transmitted by piston position linkage and a separate cable loop to move the cable drum and reposition the eccentric arm to allow the clutch cam stops to contact the steering crank. In this position, any movement of the rudder pedal is transmitted from the steering crank to the rudder pedal steering quadrant through the centering spring. This quadrant is connected to the nose wheel steering cables and is free to move the main steering system cables whenever nose wheel steering tiller is used, or drives the cables when positioned by the rudder pedal steering mechanism.
(4)
When the nose gear shock strut is extended (on lift-off), the piston position system rotates the cable drum to move the stops mounted on the eccentric arm to disengage the clutch arm from the steering arm stops. This disconnects the rudder pedal system from the steering system.
D.
Control Cables (Fig. 1)
______________
(1)
The nose wheel steering cable system consists of two sets of 3/32 inch diameter carbon steel cables with corrosion resistant steel terminal fittings. Corrosion resistant steel (CRES) cables are installed on the lower nose gear part of the cable loop.
(a)
The first set of cables (NWS) is used to activate the steering metering valve by turning the steering tiller and/or moving the rudder pedals (when engaged).
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SEE A LEFT FORWARD RUDDER QUADRANT AND JACKSHAFT ASSEMBLY
SEE B
INBD FWD
UPPER SUPPORT BRACKET
CABLE GUARD (2 LOCATIONS)
CONTROL ROD
NWSB
STEERING
NGPPB LINK CABLE
NGPPATENSIONER
TO INTERCONNECT MECHANISM A
A STEERING
NWSB
QUADRANT EXTENSION SPRINGS (2 LOCATIONS)
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本文链接地址：757 AMM 飞机维护手册 起落架 CHAPTER 32 - LANDING GEAR 3(95)
