| 摘要 |
A dot matrix printer is described in which the dots are formed by impact at an intersection between a raised ridge on a platen and a vertical ridge or bar font member. A moving belt carries a plurality of individually mounted vertical bar segments. The bar segments are each mounted on a flexible finger and can be deflected out of the path of the moving belt by impact from a print hammer mechanism. The vertical bars may be caused thusly to individually impact against a platen arranged parallel to the line of travel of the fingers. The platen may have a plurality of raised knife-edge ridges on its surface. By appropriate timing of hammer actuations, individual bar elements may be caused to impact against the knife-edge ridges on the platen. If the paper and ribbon are interposed between the bar fingers and the knife-edge ridges, a mark in the shape of the intersectional area between the bar and the knife-edge ridge can be made. If the knife-edge ridges are angled with respect to the direction of travel of paper, continuously moving paper and associated transport mechanisms may be advantageously employed. By appropriate timing of the hammer firings, together with angling of the knife-edge ridges on the platen and selection of paper translation velocity, a linear array of dots may be produced in a single row. Various other arrays of dots in succeeding rows can similarly be generated to build up desired character shapes or patterns. The mechanism reduces or eliminates the shadow printing problem inherent in intersectional printers of the type involved and enables equivalent throughput to be obtained with continuously moving paper with reduced peak power requirements.
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