Controlling The Activation And The Temperature Of The Fixing Roller (Continuous Copying); Outline; Controlling Period Of Activation - Canon NP6330 Service Manual

B. Controlling the Activation and the Temperature of the Fixing
Roller (continuous copying)

1. Outline

The copier's upper fixing roller is a special thin-coating roller, and its surface
temperature would tend to increase above the target temperature without control; to
ensure that it remains at the target temperature, its period of activation and control
temperature are controlled.

2. Controlling Period of Activation

The periods of activation for the main heater (H1) and the sub heater (H2) is
controlled according to the width of copy paper and the number of copies to be made.
As shown in Table 6-201, the period of activation of the sub heater is increased to
heat the area of contact (with copy paper; edge heating) for wide copy paper moving
through the fixing assembly.
The period of activation of the sub heater is decreased for narrow copy paper,
thereby preventing increase in temperature in areas not coming into contact with paper.
When the multi feeder is used, on the other hand, such control in relation to paper
width is only in response to an input of copy size; in the absence of an input, control is
based on A3 size (11" x 17").
A3, A4,
11" x 17",
LTR
B4
A4R,
LGL,
LTRR
B5R/STMT
COPYRIGHT © 1997 CANON INC.
Paper width
Main heater (H1)
ON for 0.3 sec
ON for 0.4 sec
Up to
ON for 0.4 sec
16th copy
17th copy
and later
Table 6-201
CANON NP6330 REV.0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Period of activation
Sub heater (H2)
ON for 0.2 sec
ON for 0.1 sec
ON for 0.1 sec
ON OFF
ON OFF
CHAPTER 6 FIXING SYSTEM
6-3