Canon Staple Finisher-AA1 Service Manual page 51

Note that this equipment does not have a paper sensor on the stack tray. Therefore, if the stack tray HP sensor (PS106) is on
when the stack tray paper surface sensor detects the paper surface (top surface of the tray), this equipment decides that the
paper in the stack tray is near empty.
Stack Tray
The paper surface detection of the stack tray is not executed in the following conditions. (This is to reduce the sound of tray
movement.)
• From power-on until the initial operation starts
• When an error or jam occurs
• When in sleep mode
• When the tray function is restricted
If the stack tray full sensors 1, 2, and 3 (PS107, PS108, and PS109) are on when the LED light from the stack tray paper surface
sensor (light-emitting) (PBA101) is blocked (; the stack tray paper surface sensor detects the paper), this equipment decides that
the paper in the delivery tray is full and stops the paper feed operation.
The following illustration shows the condition that the stack tray full sensor 1 (PS107) detected the paper full on the stack tray.
Stack Tray HP Sensor (PS106)
Stack Tray Paper Surface Sensor (Upper)
(light-receiving) (PBA102)
Stack Tray Paper Surface Sensor (Lower)
(light-receiving) (PBA103)
43
2. Technical Explanation