Ricoh LD013, Service Manual

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IMAGE FUSING AND PAPER EXIT
B039/B040/B043 6-62 SM
6.13.5 FUSING TEMPERATURE CONTROL
Overview
The fusing temperature is controlled using the fusing thermistor [A].
The CPU checks the output from the fusing thermistor once a second. The CPU
compares the current and previous temperature, then decides the power-on ratio
for the next second. To maintain the target temperature, the CPU controls the
fusing lamp power-on ratio as shown in the following table (the temperature control
algorithm only works with whole numbers).
The fusing lamp works to maintain a target fusing temperature of 175
°
C during
copying.
Initializing
Sampling cycle: 1 second
Soft start setting: 3 cycles
Current minus Target
Previous minus Current
–3
°°°°
C or
less
–2
°°°°
C or
–1
°°°°
C
0
°°°°
C
+1
°°°°
C or
+2
°°°°
C
+3
°°°°
C or
more
–3
°
C or less
100% 50% 0% 0% 0%
From –2
°
C to –1
°
C
100% 50% 0% 0% 0%
0
°
C
100% 50% 0% 0% 0%
From +1
°
C to +2
°
C
100% 50% 0% 0% 0%
+3
°
C or more
100% 50% 0% 0% 0%
Ratio (%): The proportion of time that the fusing lamp power is on
B039D506.WMF
[A]