Paper Feed And Misfeed Detection Timing - Ricoh FT 4215 Service Manual

DETAILED SECTION DESCRIPTIONS

8.2 PAPER FEED AND MISFEED DETECTION TIMING

0
Timing Pulse
(4 ms/pulse)
400 ms
Start Key
Main Motor
100
1st Feed Clutch
Pick-up Roller
Release Sol.
Registration
Sensor
Registration
Clutch
Exit Sensor
PAPER FEED AND MISFEED DETECTION TIMING
The registration sensor and the exit sensor monitor the movement of the
paper through the paper path. If the CPU determines that a misfeed exists,
the Check Paper Path and the Misfeed Location indicators turn on. When the
main switch is turned on, the CPU checks these two sensors for initial
misfeed. During the copy cycle, the CPU performs three kinds of misfeed
detection:
J1: Checks whether the registration sensor is actuated within 10 pulses (40
milliseconds) after the registration clutch turns on. (Misfeed Location indicator
"B" turns on.)
J2: Checks whether the exit sensor is actuated within 700 pulses (2.8
seconds) after the registration clutch turns on. (Misfeed Location indicator "C"
turns on.)
J3: Checks whether the copy paper has passed through the exit sensor 2.75
(A4 sideways) or 2.80 (Letter sideways) seconds after the exit sensor has
been actuated. (Misfeed Location indicator "D" turns on.)
100 1500 2000
1750
1877
J1
2010
120 ms
2000
18
2500 3000
1750
1877
2273 (A4 S) 2273 (A4 S)
2285 (LT S)
J1
2010
120 ms
2000
J2
2700
2.75 sec (A4 sidewise)
2.80 sec (LT sidewise)
31 March 1994
3500 4000
1750
1877
2285 (LT S)
J1
2010
120 ms
2000
J3 J2
2700