Platen-Head Contact Switching Mechanism According To Tape Cassete - Brother PT-2500PC Service Manual

2.1.3 Platen-head Contact Switching Mechanism According to Tape Cassette
This mechanism consists of the cassette rod, release lever, and release rod.
As described in Subsection 2.1.2, loading a tape cassette and closing the cassette cover
pushes down the release lever which presses the roller holder ASSY against the thermal
head. If the roller holder ASSY is kept pressed against the thermal head for a long time,
however, the platen could be deformed. To avoid it, this mechanism switches the pivot
angle of the roller holder ASSY so that the roller holder ASSY does not come into contact
with the thermal head when no tape cassette is loaded.
If you load a tape cassette, the cassette edge presses the cassette rod to turn it
clockwise (when viewed from the top). Engaged with the cassette rod, the release lever
tilts ("A" in the illustration below) so that closing the cassette cover presses the release
lever at the lower end of box "X." Accordingly, the roller holder ASSY pivots at a great
angle, pressing the platen against the thermal head.
If no tape cassette is loaded, the release lever stands straight ("B"). When you close the
cassette cover, the release lever comes into box "X." so that the roller holder ASSY
pivots at a slight angle, preventing the platen from coming into contact with the thermal
head.
When a tape cassette is loaded
When no tape cassette is loaded
Fig. 2.1-3 Platen-head Contact Switching Mechanism According to Tape Cassette
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