Overview/Configuration; Overview; Detection Jams; Jam Detection Outline - Canon L90 Series Service Manual

5.1 Overview/Configuration

5.1.1 Overview

[2]
[3]
[1] Face-down delivery roller
[2] Fixing pressure roller
[3] Transfer charging roller
[4] Separation pad
[5] Pickup roller
[6] Photosensitive drum
[7] Fixing film unit
Pickup and Feed Operation
The pickup/feed system consists of the main motor, solenoid, and various rollers.
The system operates as follows:
1) The DCNT board turns on the main motor (M1) immediately after it receives the print command from the SCNT board. In response, the rollers other than the
pickup roller start to rotate.
2) When the initial rotation ready state (Note) starts, the pickup solenoid (SL1) goes on for about 0.2 sec, causing the rotation of the main motor to rotate the pickup
roller.
3) The pickup cam starts to rotate in keeping with the rotation of the pickup roller. The shape of the cam causes the spring to push up the holding plate. The paper
on the holding plate is picked up by the work of the pickup roller.
4) The DCNT board sends the laser beam detection signal (/BD) to the SCNT board a specific period of time after the leading edge sensor (PS801) detects the
leading edge of print paper that has been picked up.
5) The SCNT board sends video signals to the laser/scanner assembly based on the /BD signal so as to form an image on the surface of the photosensitive drum,
making sure that the leading edge of the image and the leading edge of the print paper will match.
6) The print paper is then moved to the face-down tray for delivery by the work of the pressure roller and the face-down delivery roller.
When the initial rotation ready state:
The machine is in an initial rotation ready state when the main motor is on and, in addition, the fixing assembly temperature has reached a specific level and
the scanner motor has reached a specific revolution.

5.2 Detection Jams

5.2.1 Jam Detection Outline

5.2.1.1 Type of Jams

The machine identifies the following types of jams:
Pickup Delay Jam
The paper leading edge sensor does not go on within a specific period of time after pickup starts.
Pickup Stationary Jam
The paper leading edge sensor goes on, but does not go off within a specific period of time.
Delivery Delay Jam
The paper leading edge sensor goes on, but the delivery sensor does not go on within a specific period of time.
[1]
PS803
PS804
[7]
[6]
PS801
PS802
[8]
SL1
[5]
[4]
M1
F-5-1
T-5-1
[8] Toner sensor
[PS801] Paper leading edge sensor
[PS802] Paper width sensor
[PS803] Delivery sensor
[PS804] Paper width 2 sensor
[M1] Main motor
[SL1] Pickup solenoid
Chapter 5
0018-4902
0018-4903
5-1