GILLIG LOW FLOOR, Руководство по обслуживанию

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Air System
DOOR CONTROL OPERATION
Entrance Door
The entrance door is opened and closed by an air operated door motor. The electrical Door Control
switch on the driver’s console activates a solenoid to operate the air system to drive the door motor.
Refer to the door air schematic in Figure 6-
4 . The door air is supplied by the accessory air tank. The
door motor consists of two opposing air cylinders. The small cylinder opens the door and the large cylin-
der closes the door. The open cylinder (small cylinder) is always pressurized.
For more detail on door operation and adjustment, refer to Chapter 11– Body and Interior.
Door Closing
To close the door, the driver operates the Door Control valve that activates the solenoid at the close
cylinder. The close cylinder (large cylinder) is pressurized at the same pressure as the open cylinder. The
larger area of the close piston overpowers the smaller open cylinder and closes the door. When the door
is closed, the close cylinder remains pressurized to hold the door closed tightly.
Door Opening
To open the door, the close cylinder is evacuated. At about 65 to 70% of the operating cycle, the air flow
is slowed to give a cushioning effect at the full open position of the door. The open cylinder remains
pressurized while the door is open.
Manual Opening
A manual door opening valve, located above the front door, will evacuate the air from both cylinders,
allowing the door to be manually pushed open.
Exit Door
The exit door is opened by an air cylinder and closed by a spring (Figure 6-4). When the driver operates
the Door Control valve to open the door, and a passenger presses the door touch bar, the solenoid at the
door motor opens and pressurizes the open cylinder. The cylinder overpowers the spring pressure and
the door opens.
To close the door, the air is evacuated from the cylinder and the spring closes the door.
Door Override (SWAT) Switch
The door override switch, located at the access door on the upper-right-hand corner of the rear engine
door, will wake up the I/O system (if it is in sleep mode) and activate both door motor solenoids to
open both the front and the back doors. Unlike the door control handle on the driver’s console, this is a
maintain switch, not a momentary switch. When switched to the open, the doors will stay open until you
switch back to close them.