| 摘要 |
PURPOSE:To arranges so that a large power supply may not have to be provided and printing quality may not deteriorate due to the reduction of dot driving force by performing printing action with some of the printing heads during high density printing dot operation. CONSTITUTION:The power supply capacity of a power supply unit 12 is set on the basis of an average printing dot density during printing. When the printing dot density has become high and magnet driving voltage has become low, a power supply voltage discrimination 13 discriminates it, transmitting a power supply voltage drop signal to a main control 11. The main control 11 transmits a printing action stop signal to the first head control circuit 8a, the second head control circuit 8b and spacecontrol circuit 9. Next, the main control 11 gives a printing command and printing data to only the first head control circuit 8a, thus allowing printing action to be performed. Following this process, transmission of a signal to the first head control circuit 8a is suspended, and instead allows the second head 4b to operate for printing without line feed, completing a single line printing. |
