| 摘要 |
PURPOSE:To reduce the number of switching transistors as a signal grounding control means for each drive coil to half the required number of conventional transistors by applying a drive current to each drive coil corresponding to one array of printing means and the other at varying timing. CONSTITUTION:A printing head 10 has two arrays of line heads H1, H2. Ham mer pins (H11,...,H1n), (H21,...,H2n) of each array H1, H2 are paired with each hammer pin opposed to one end of each one of the former at the same position. Then these pairs are sequentially divided into 'n' number of groups. After this, the drive coils, e.g. L11 and L21 of each group are commonly earthed through a single switching transistor 801. The waveform of a signal running through the drive coils L11, L21 is delayed in timing by a single waveform. For this reason, signal currents of both coils never run to the switching transis tor 1 in an overlapped form, so the same capacity of the coil as the conventional one is acceptable. The same is true about the drive coils of other groups. Also the signal current to be output from a signal power supply has a peak value which is half the value ever shown by the conventional cases. |
