Canon MF8100 Series, Service Manual, Page: 53 / 296

Chapter 2
2-17
F-2-30
2.3.4.3 Developing Rotary Engaging Control
0008-1708
This control is utilized to engage a developing cylinder in the rotary to the drum in order to transfer the toner image on the drum onto the ITB.
In rotary engaging control, the DCNT Board switches the rotational direction of the engaging motor (PM704) and moves the rotary to either of two positions, en-
gaging position and disengaging position.
At the time of rotary engaging (travelling from a disengaging position to an engaging position), the DCNT Board rotates the engaging motor clockwise for a spec-
ified period. This allows the rotary engaging cam to rotate and then the engaging plate is pressed out. The developing cylinder is engaged to the drum.
At the time of rotary disengaging (travelling from an engaging position to a disengaging position), the DCNT Board rotates the engaging motor counterclockwise
and instructs the reverse operation of rotary engaging. Then the developing cylinder is disengaged from the drum.
A mechanism used in this control is also used in a memory tag contact engaging operation.
Developing rotary position detection is performed by the DCNT Board monitoring the rotary engaging sensor (PS712).
<When the Y cartridge is at developing position>
PS51
SL93
Developing rotary
home position sensor
Bk cartridge flag
C cartridge flag
M cartridge flag
DCNT Board
/RHLDSLD R
O
THPS
Developing rotary
stopper solenoid
Photosensitive
drum
<When the Y cartridge is at replacing position>
PS51
Y cartridge flag
PS51
Y cartridge flag
Photosensitive
drum
Photosensitive
drum
Y
Bk
M
C
Y
Bk
M
C
Y
Bk
M
C
Home position flag
(Y cartridge flag)
Developing rotary/
toner level detection circuit