| 摘要 |
PURPOSE:To make the printing density adjustable by mounting a means for variably controlling the oscillating frequency of an oscillator, a means for modulating the pulse width of a printing signal according to the change in oscillating frequency of the oscillator, and a printing means for changing the travel speed at the printing position. CONSTITUTION:An oscillator mounted on a nozzle is driven by a VCO(voltage control oscillator) 29. The oscillating frequency of the VCO 29 is varied by a variable resistance 28. In an F/V(frequency-voltage) converter 31, a motor 23 is driven in accordance with the oscillating frequency of the VCO 29, a rotating drum 21 is rotated, and recording paper 22 is fed in accordance with an interval of ink drop separation. A CPU 27 inputs the output of the VCO 29 and the output of an encoder 24 detecting the rotating state of a rotating drum 21 and outputs a printing signal after changing the pulse width thereof. On this output, a high voltage driver 30 drives a charged electrode on a head part 20, and the head part 20 is driven in accordance with the output of the VCO 29. In this manner, printing density can be adjusted simply by adjusting the variable resistance 28 while observing an image to be printed. |
