Chapter Ii Theory Of Mechanism Operation; Printing Mechanism; Construction Of Thermal Head; Theory Of Printing - Brother SC-2000 Service Manual

CHAPTER II THEORY OF MECHANISM OPERATION

1. PRINTING
1.1

Construction of Thermal Head

The thermal head contains 960 heating elements vertically arranged. The size of
one heating element is 0.035 mm wide by 0.060 mm high, as shown in Fig. 2.1.
1.2

Theory of Printing

During printing operation, the thermal head crimps the ink ribbon and a draft sheet
(or an ID label) on the cylindrical rubber platen. In this state, the CPU selects the
required heating elements out of the 960 heating elements to energize them. When
the energized heating elements are heated, the ink in the ink ribbon is fused, and
the ink is transferred to an adhered draft sheet (or an ID label) to print dots. The ink
ribbon and the draft sheet (or the ID label) are fed to the next printing position
simultaneously at the same speed to start the next printing cycle. By repeating the
printing cycles in this manner, a character and graphics is printed on the surface of
a draft sheet (or an ID label).
1.3

Configuration of Character and Graphics

The driving motor continuously feeds a draft sheet (or an ID label) and the ink
ribbon by 0.0423 mm in 9 ms, during which the CPU heats the thermal head once to
print a character and graphics.
MECHANISM
40.7925 mm
0.035 mm
Fig. 2.1 Heating Elements of the Thermal Head
0.0425 mm
0.060 mm
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