Canon Finisher-AK1, Service Manual

Page: 23 / 374

2
2
2-8
2-8
Technology > Stacking Unit > Tray Paper Surface Detection
Technology > Stacking Unit > Tray Paper Surface Detection
Tray Paper Surface Detection
The machine is equipped with a mechanism to detect the position of the top of the stack
deposited in its 2 trays.
The trays are each fitted with a sensor PCB that consists of a light-emitting segment (UN15,
UN17) and a light-receiving segment (UN16, UN18).
The light-emitting segment is arranged at the rear of the machine, and is a LED. The light-
receiving segment, on the other hand, is found at the front of the machine, and it consists of 3
photosensors.
When the power is turned on or a jam has been removed, the finisher controller PCB checks
the 3 photosensors (light-receiving segment) as soon as the LED (lightemitting segment)
goes on.
As more and more sheets are deposited in the tray, the light reaching the light-receiving
segments will be blocked, causing the finisher controller PCB to move down the tray to keep
the top of the stack at a specific level.
When the tray becomes full of paper (i.e., light blocked, not reaching any of the 3
photosensors), the finisher controller PCB switches over to a different tray for subsequent
delivery. If the newly selected tray is full, it will stop the operation of the machine, and will
indicate the fact to the host machine.
[1]
[1]
[2]
[3]
[4]
[5]
UN15
UN16
UN16
UN17
UN18
1
2
3
UN16
1
2
3
[1]
[2]
[1]
[2]
[6]
[1] Paper [4] Non-sort delivery roller
[2] Tray A [5] Stack delivery roller
[3] Tray B [6] Tray descent movement (sample)
UN15 : Tray A paper surface sensor
(light-emitting)
UN17 : Tray B paper surface sensor
(light-emitting)
UN16 : Tray A paper surface sensor
(light-receiving)
UN18 : Tray B paper surface sensor
(light-receiving)
F-2-8