摘要 |
In printing head of a dot printer according to this invention, a groove having width a little greater than diameter of top end of a needle is formed in front of a needle guide to guide the needle, position of top end of the needle is specified between the bottom of the groove and front surface of the needle guide, when the needle pushes through the printing head it returns rapidly, when top end of the needle is deformed it does not stick to the needle guide, a gauge spacer is interposed between the yoke and the guide holder to be assembled thereby position of top end of the needle is specified, and plural sheets of other spacer are overlaid and removed separately during grinding top end of the needle thereby the needle without deformation at top end can be formed and used for a long time.
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