Conventionally, various tape printers, which can print on a print tape of a long printing medium, displaying a text composed of characters inputted with input means such as a keyboard, have been suggested. In the tape printer, the print tape is generally supplied from a tape cassette in which the print tape, an ink ribbon, and a release paper are wound on each spool and housed in a predetermined-shape cassette.
In a tape cassette housing part of the tape printer, there are provided with a print head for printing on the tape and a platen for feeding the tape. In printing, the print tape is pressed against the print head by the platen to be printed the text, and discharged as a printed tape. Herein, when the tape cassette is to be removed for replacement, the print head and the platen need to move away from a pressing position of the print tape in order to release pressure exerted on the print tape by the print head and the platen. Accordingly, at least one of the print head and the platen is made movable, and a release member is provided to move the print head or the platen between the pressing position and a withdrawing position. Further, a cassette cover for covering the tape cassette installed in the tape cassette housing part is also provided. In printing, the cassette cover is closed to prevent an entry of something extraneous from outside.
Japanese Patent Application laid-open No. H10(1998)-100494 discloses, as the release member described above, an engagement portion provided in the cassette cover for moving a platen holder (the platen) in the pressing position when the cassette cover is closed, and an elastic member for moving the platen holder (the platen) to the withdrawing position when the cassette cover is opened.
However, in the tape printer of the above publication, there is a risk that, while the tape printer is stored for a long period without the tape cassette, keeping the platen holder at the pressing position, the print head and the platen adhere to each other, and they can no longer return to the withdrawing position with a force of repulsion. In case the repulsion of the elastic member is enhanced to solve the problem, this causes deformation of the platen, and the increase in cost since each part also needs to be reinforced.