TM200 Service Manual
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Printer Mechanism
Thermal head Module
The thermal head is designed so its heating element is positioned where it comes into
contact with the platen. The roll paper wrapped around the platen is kept in contact
with the thermal head’s heating element at a prescribed pressure, and printing is
performed when heat is generated by the heating element.
Printing is performed according to the following steps:
1. The print signal sends a prescribed energizing pulse to the electrodes that
correspond to each dot to be printed.
2. Resistors at each electrode generate heat.
3. The heat energy generated by the resistors is transmitted to the roll paper surface
through the protective layer to the paper’s heat-sensitive layer, causing coloration
of the paper.
Figure 2.2 Frame cover open
The paper outlet of the printer is covered, and even if paper output becomes blocked for
some reason, there is enough room in the space between the platen and frame cover for
accumulation of two or three normal length receipts (the length of one sheet is assumed
to be 80mm or less). This reduces the chance of receipt paper becoming bent and of the
print pitch becoming uneven. Paper that accumulates can be easily pulled out of the
printer after the paper outlet is opened.
