AFT SMALL CARGO DOOR SYSTEM -MANUAL OPERATION
EFFECTIVITY BEJ ALL 52-35-00
Page 39
D633W101-BEJ May 05/2002
AFT SMALL CARGO DOOR SYSTEM -MECHANICAL FUNCTIONAL DESCRIPTION
Unlatch
Either the lift/latch power drive unit (PDU) motor or the lift/latch manual drive can supply power to lift the door out of the latch (plug) position. Linear movement of the actuator goes through linkage to turn the lift/latch torque tube.
A cam on the torque tube releases the vent door crank. The crank releases pressure on the vent door push rod. The vent door springs open the vent door. As the vent door opens, the rod moves the crank to release the cam so the torque tube can rotate completely. The latch bungee helps complete the rotation of the torque tube.
Cranks on the ends of the torque tube push against latch tracks (not shown) to lift the door out of the latched position. Linkage that attaches the hinge arm to the door, lets the door move up out of the latch (plug) position without hinge arm movement.
Linkage transmits movement of the lift/latch torque tube to the lockout torque tube. The lockout cams on the torque tube move against the lift pins (not shown) on the hinge linkage. This locks the hinge linkage in the door lifted position so the hinge arms can open the door.
Open/Close
Either the hinge power drive unit (PDU) or the hinge manual drive can open the door. Rotary movement goes through the hinge torque tubes to rotary actuators. The rotary actuators move the hinge arms.
The hinge arms push against the linkage that attaches the arms to the doors. The door moves out and rotates up.
Close
Close movements are the reverse of open movements.
Latch
latch movements are the reverse of unlatch movements. At the bottom of the latch movement, the hooks and stops along the top and bottom of the door, and the stop pins along the sides of the door transmit the pressurization load on the door to the door cutout.
EFFECTIVITY BEJ ALL 52-35-00
Page 40
D633W101-BEJ Sep 05/2002
AFT SMALL CARGO DOOR SYSTEM -MECHANICAL FUNCTIONAL DESCRIPTION
EFFECTIVITY BEJ ALL 52-35-00
Page 41
D633W101-BEJ Jan 05/2002
AFT SMALL CARGO DOOR SYSTEM -ELECTRICAL FUNCTIONAL DESCRIPTION
General
Sensors on the door give inputs to the proximity sensor electronics unit (PSEU). The PSEU uses the inputs to turn on door position indication lights, and enable door control relays.
The system uses ground handling power. Relays supply the three phase power in specified configurations to the hinge and the lift/latch power drive units (PDU). The phase configuration controls whether a PDU opens or closes the door.
There are internal and external control switches. The internal switch has priority over the external switch.
Arm
Movement of an arming switch to either ARM position energizes the arming relay. This supplies power to the hinge and lift/latch relays.
Unlatch
The PSEU uses an input from the door lifted sensor to enable the lift/latch up relay. Either control switch in the OPEN position energizes the relay. The relay puts the power phases in the correct configuration so the lift/latch power unit lifts the door out of the latch (plug) position.
The PSEU uses inputs from the door down and door latched sensors to make the door latched light go off.
EFFECTIVITY
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