Dot matrix printer with suppressed printing noises

Abstract

A dot matrix printer of a dispersion printing type in which a printing noise is suppressed and dots arranged in longitudinal rows are driven while shifting the timing for every print wire dot. The present dot matrix printer is characterized by a construction in which respective print wires are driven at different timings within one pitch, and a space around a print head is surrounded by a housing and a platen, and a sound generated in the space is transmitted outside through walls. Further, the present dot matrix printer is characterized in that there is provided a memory storing printing intervals among the whole dots and print head conduction time, and the print head is driven in accordance with information read out of said memory in order to correct deviation of dot rows arranged in a longitudinal direction of the print head from perpendicularity. According to the present dot matrix printer, since the print head is driven at a high frequency by an inexpensive control unit, the noise frequency at printing with the print head becomes high, and the generated noise is transmitted outside through walls. Therefore, attenuation in a high-pitched tone compass is large through walls, thus exhibiting an effect that the operation sound of the printer leaking outside is made smaller.