Citizen CL-E700 Series, Technical Manual

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Chapter 2 Operating Principles
2-2.
Operation of Control Parts
CL-E700 series
2-30
If the temperature of the “SA Ribbon Motor F” exceeds a certain level, the ribbon motor
temperature sensor output voltage becomes lower than the reference voltage, and the pin 1 of
U8A goes to “Low” level. At this time, pin K1 (nTMPERR) is “Low” and the FPGA (U5) detects
an abnormally high temperature.
In this abnormal state, the printer stops +24V DC supply to the “SA Ribbon Motor F”. Also, it
stops +24V DC supply to the “SA PF Motor” and “SA Head”.
(6)
Ribbon tension sensor (SA Ribbon Sensor)
The ribbon tension sensor consists of two photointerrupters and is located on the ribbon
take-up side (front side) of the “Unit Ribbon”. It is used to detect the ribbon tension on the
ribbon take-up side to maintain the ribbon tension on the take-up side constant.
* In power saving mode, +3VIO is not supplied. For details, refer to “ 2-2-6(1) Power supply
circuit ”.
Ribbon tension sensor operation when the ribbon slacks:
During printing, the ribbon is fed forward together with the media. Thus, the ribbon on the
take-up side slacks and the projections of the “SA Ribbon Tension Shaft F” come off the
photointerrupters (PS401 and PS402) on the “SA Ribbon Sensor”. Thus, the photointerrupters
turn ON, and pin 26 (RIBSENS_R1) and pin 31 (RIBSENS_R2) go to “High” level.
At this time, the printer increases the rotational speed of the “SA Ribbon Motor F” to wind the
take-up side ribbon faster to give more tension to the ribbon.
Ribbon tension sensor operation when the ribbon tightens:
When the ribbon is wound and tightened, the projections of the “SA Ribbon Tension Shaft F”
are inserted into the photointerrupters (PS401 and PS402) and pin 26 (RIBSENS_R1) and pin
31 (RIBSENS_R2) go to “Low” level.
At this time, the printer decreases the rotational speed of the “SA Ribbon Motor F” to give less
tension to the ribbon.
During printing, the above ribbon tension control cycle is repeated to give constand tension to
the take-up side ribbon. Further, by using 2 photointerrupters, ribbon tension is finely
controlled.
[SA Ribbon Sensor]
Ribbon
Sensor1
2
3
1
PT401
PS401
R401
4
Ribbon Sensor
2
3
1
J606
4
[SA Ribbon
Control PCB]
11
10
J601
CPU
26
31
Ribbon
Sensor2
PS402
R402
1 1
+3.3V
RIBSENS_R1
RIBSENS_R2
C104
RIBSENS_R1
RA17
1 2
U12A
C105
R77 R78
3
4
U12B
RIBSENS_R2
[SA Main PCB]
14-16
14-16
J304
22
21
J301
22
21
8 8
RIBSENS_R1
RIBSENS_R2
3-6
J4
[SA Relay PCB]
U1A
3-6
11
10
+3VIO
+3VIO
+3VIO
P6_5
P6_6