Brother PT1090 - P-Touch - Labelmaker, Руководство по обслуживанию

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II - 1
CHAPTER II THEORY OF OPERATION
2.1 Outline of Mechanisms
2.1.1 Print Mechanism
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Structure of Thermal Head
This machine uses direct thermal printing. The thermal print head has a heat
generator consisting of 64 heating elements which are vertically aligned in 180 dpi as
shown in Figure 2.1-1. Each heating element is 0.18 mm wide by 0.127 mm high.
Figure 2.1-1 Heat Generator of Thermal Head
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Printing Process
When the cylindrical rubber platen is pressed against the thermal print head with the
tape and ink ribbon sandwiched inbetween, the CPU applies current to the selected
ones out of the 64 heating elements.
If the selected heating element(s) generates heat, the ink on the sandwiched ribbon
will be melted and transferred to the tape, producing a dot(s) on the tape. The ink
ribbon and the tape are advanced and then the next heating cycle is repeated, thus
forming a graphic pattern on the tape.
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Graphic Pattern Formation
While the drive motor (DC motor) feeds the tape and ink ribbon by 0.141 mm for 14.1
ms, the thermal head generates heat once. The feed amount of 0.141 mm is smaller
than the width (0.18 mm) of the heating elements so that the heat generated at one
heating cycle will overlap with the next heating cycle. This forms a graphic pattern
having no gap between adjacent printed dots.
9.024 mm
0.127 mm
0.18 mm