(2)  
Two active seals, one static and one dynamic, keep an air-oil mixture within the cylinders. Two sets of spare seals are stored in the shock strut to aid active seal replacement.

 (3)  
The shock strut is divided by the orifice plate into upper, middle, and lower chambers. The upper chamber contains oil and nitrogen, the middle and lower chambers contain oil.

 (4)  
During shock strut compression the tapered metering pin adjusts the flow of oil from the middle chamber into the upper chamber to control the absorbtion of impact loads. At the same time some oil will flow from the middle chamber through holes in the upper bearing into the lower chamber.

 (5)  
During strut extension the rebound restrictor decreases the flow of oil from the lower chamber into the middle chamber to control the rate of strut extension.

 (6)  
Upper and lower centering cams between the inner and outer cylinders assist in aligning the nose gear in the forward position during retraction.

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MAINTENANCE MANUAL

LOCK SPRING
UPPER
FORWARD DRAG STRUT
LOCK LINK
AFT LOCK LINK
LOWER
DRAG STRUT

FORWARD TOW FITTING 
1  IF INSTALLED 
Nose Gear Figure 1 

UPPER TORSION LINK
LOWER TORSION LINK
AFT TOW FITTING 1
L25033
 

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 (7)  
The shock strut includes lugs for the attachment of the retract actuator, steering actuators, torsion links, drag strut, forward and aft tow fittings, aft door operating mechanism, and the one-piece axle.

 E.
Torsion Link (Fig. 1)

____________
 (1)  The torsion link consists of an upper and lower link connected to the aft side of the shock strut. The upper link is attached to the outer cylinder and the lower link is attached to the inner cylinder. The two links are connected together to allow for vertical extension and compression of the shock strut while preventing rotation between the inner and outer cylinders except while steering.
 CAUTION: DO NOT USE UPPER TORSION LINK AS A STEP WHEN DISCONNECTED
_______ FROM LOWER LINK. TARGET FOR NOSE GEAR NOT COMPRESSED PROXIMITY SENSOR WILL BE CONTACTED AND DEFLECTION OF TARGET MAY OCCUR.
 (2)  
The torsion links are disconnected from each other to allow the cylinders to rotate to angles larger than normal steering limits for towing purposes. When the links are disconnected from each other, the upper link should never be used as a step while preforming maintenance, as any excessive force on the link could damage the air/ground sensor targets on the sides of the link.

 F.
Tow Fitting (Fig. 1)

___________
 (1)  
A forward tow fitting is attached to the shock-strut inner-cylinder. The tow fitting is used to tow the airplane in the forward or the aft direction.

 (2)  
ON SOME AIRPLANES; an aft tow fitting is attached to the shock-strut inner-cylinder. The tow fitting is used to tow the airplane in the aft direction.

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MAINTENANCE MANUAL

UPPER CHAMBER
CHAMBER MIDDLE  PLATE OROFICE PIN METERING 
CYLINDER OUTER  BEARING UPPER 
CYLINDER INNER  RESTRICTOR REBOUND 
CAM UPPER CENTERING 
CHAMBER LOWER  CAM LOWER CENTERING 
VALVE OIL CHARGING 
DYNAMIC SEAL 
　
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本文鏈接地址：757 AMM 飛機維護手冊 起落架 CHAPTER 32 - LANDING GEAR 1(168)