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• Head up/down motor (M902)

Motor which moves the head up and down.
There are three head positions-”Initial”, “Paper Pull In”, and “Print”.

• PLATEN motor (M904)

Stepping motor which moves the print paper front and back. Motor rotation consists of two speeds. (Printing:Slow, Paper

forward/reverse:Fast)

Speed is switched by switching Q902 according to the STPLOW signal (Pin *¡ of IC505) from the mechanism microprocessor.
Motor rotation is controlled by the STEP PH1 to PH4 outputs from the system controller (IC503).

• Ribbon motor (M903)

Motor which rewinds the print cartridge.

• Fan motor (M901)

Motor which rotates the FAN and lowers the head temperature.
The voltage of the thermistor at the side of the head is input to the system controller (Pin (º of IC503), the head temperature

is detected, and data is serial-transferred to the mechanism controller (IC505).

When the head temperature is high, the motor driver rotates the FAN motor using the output from the mechanism

controller. When the thermal head temperature decreases, the FAN motor stops.

Attach the FAN motor facing the direction in which it can suck in air from outside.

•

Head position sensor 0, 1
Detects three head positions.

•

Ribbon door sensor
Detects half-insertion of the print cartridge.

•

Ribbon cord sensors 1, 2
Detects the presence of the print cartridge.

•

Ribbon cord sensors 0, 1, 2

•

Paper edge sensor
Detects the insertion and position of the paper during printing.

•

Jamming detection sensor
Detects paper jamming. Detects the length of the print paper together with the paper edge sensor.

•

Ribbon mark sensor 1
Detects the long black line at the top of the print cartridge, and detects the starting position for one image.

•

Ribbon mark sensor 0
Detects the short black line of the print cartridge, and detects the border between colors.

•

Feeder position sensors 0, 1
Detects the up plate position and lock lever position.

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The thermal head has high durability and does not require replacement in normal use. There is also no need for worry of

contamination.

When the head is faulty, symptoms can be seen such as a line forming in the printing direction or printing may not be

possible at all.

If printing of mixed colors or printing of dust-like dots are seen, it means that the print cartridge is dusty or the print

paper is dirty. Rewind the print cartridge used and check if it is normal.

The head arm fixing screw is adjusted appropriately at factory shipment, therefore never rotate it. (Refer to “Replacing

the Head” in the service manual for its location.)

Silicon compound is applied between the thermal head and heat sink. When replacing the head, make sure it does not get

onto the other parts.

If the silicon compound gets onto the side of the print cartridge of the head, clean off with alcohol.

Assemble with the head raised.
However, rotating the head drive gear excessively will move it to an unlikely position in the usual mechanism operations.

If this occurs, the head will not move to the appropriate position when the power is turned on, and the mechanism
operations will be faulty.

To avoid this, assemble so that the pin of the power gear is at the top. (See Fig. 4)

The head drive gears (R) and (L) need to be phase-adjusted.

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When assembling the mechanism deck, lift up the paper guide slightly, and assemble so that it goes inside the mechanism

deck.

If the paper guide is not inside the mechanism deck, paper printed in the manual mode will be ejected from the auto

feeder insertion slit.

Black grease is applied at the contact point between the left and right head arm assemblies and the power gear.
When this grease runs out, symptoms may appear such as the wearing of the head arm assembly, drop in head pressure

which causes printing to become light, and mechanical noise of metal parts, etc.

Apply grease if the customer used frequently.

Clean the pinch roller with ethyl alcohol when it becomes dirty. As it turns black with use, replace it if the print surface

of the print paper becomes black.

If paper chips are adhered to the capstan roller, remove with adhesive tape, etc.

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IrDA is an industrial organization established in June 1993 with the aim to standardize and spread data communication

using infrared ray.

IrDA Ver 1.0 is the standard for performing cordless RS-232C communication on the PC using infrared ray.

As use of infrared ray is not restricted under law, it realizes a universal communication method. (Communication

methods using radio wave is restricted by law in each country according to purpose of use.)

As infrared ray devices are relatively small, cheap, and consumes little power, they can be set to higher communication

speeds over RS-232C cables, etc.

• Communication method

Infrared signals are output from the LED (transmitter) and received by the photo-diode (receiver). Red and black optical

filters are located in front of the transmitter and receiver to eliminate visible light and filter only infrared ray through.

• Layout of devices

Infrared ray cordless communication is performed by facing the infrared ray transmitter and receiver at each other.
Position the transmitter and receiver so that they are within 1 m apart and within a ± 15° cone from the optical axis

which is the direction traveled by the infrared ray.

Infrared ray travels while spreading up, down, left and right of the optical axis. The infrared ray strength attenuates

inverse-proportionally to the square of the distance, and therefore communication is disabled if the position is deviated.