Canon LBP1760P, Service Manual

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• For paper 200mm or more: T= about 3.2 sec.
• For paper less than 200mm: T= about 5.7 sec.
b. During paper feeding
The CPU assesses a delivery delay jam if the fixing unit delivery sensor 2 (PS106) does not detect
the leading edge of the paper within the prescribed period of time (about 0.47 sec.) after the
PS501 detects the leading edge.
c. When having detected the paper wrapped around the pressure roller
When the length of the paper detected by the top of page sensor (PS103) is 200 mm or longer,
the CPU assesses a delivery delay jam if the fixing delivery sensor 1 (PS501) detects the no paper
condition within the specified period of time (about 1.5 sec.) after PS103 detects the trailing edge
of the paper.
4. Delivery stationary jam
a. During paper feeding
The CPU assesses a delivery stationary jam if the fixing unit delivery sensor 1 (PS501) does not
detect the trailing edge of the paper within the prescribed period of time (about 3.5 sec.) after
the top of page sensor (PS103) detects the trailing edge or if the fixing unit delivery sensor 2
(PS106) does not detect the no paper condition within the prescribed period of time (about 4.7
sec.) after the fixing unit delivery sensor 1 (PS501) detects the leading edge of the paper.
b. When WAIT period starts
The CPU assesses a delivery stationary jam if the fixing unit delivery sensor 1 (PS501) detects
paper when the WAIT period starts, if PS501 detects paper within about 2 sec. after the WAIT
period starts, or if the fixing unit delivery sensor 2 (PS106) detects paper during the WAIT peri-
od.
5. Retry control
Retry control is a method which redresses the pick-up delay jam due to pick-up error. It con-
ducts pick-up operation twice and is applied to all the pick-up entrances except the duplexing
unit. Retry control for each pick-up entrance is described below. Jam detection time at the retry
is the same as that at the first try.
a. Standard cassette
The printer conducts the same pick-up operation as the 1st try if the pre-feed sensor (PS102)
does not detect the leading edge of the paper within the prescribed time after the pick-up starts.
b. Multi-purpose tray
The CPU rotates the pick-up roller once again if the top of page sensor (PS103) does not detect
the leading edge of the paper within the prescribed time after the pick-up starts. Then, the CPU
rotates the pick-up roller one more time if the PS103 does not detect the paper within the pre-
scribed time.
c. Optional paper feeder cassette
The CPU sends retry instructions to the paper feeder if the pre-feed sensor (PS102) does not
detect the leading edge of the paper within the prescribed time after the pick-up starts.
d. Envelope feeder
The CPU sends retry instructions to the envelope feeder if the top of page sensor (PS103) does
not detect the leading edge of the envelope within the prescribed time after the pick-up starts.
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CHAPTER 2