| 摘要 |
PURPOSE:To obtain clear printing by a method wherein the rise time of a driving voltage waveform is set to be longer than the fall time thereof and thereby the velocities of ink particles from a plurality of nozzles are adjusted to be uniform. CONSTITUTION:In the driving circuit of a recording head, a charge is given from an emitter follower Q2 to a piezoelectric element C0 via a resistor R4 and an output voltage rising at a prescribed time constant appears at an output terminal I2 in a period T2 when a switching transistor Q1 is OFF. When the transistor Q1 is turned ON, the charge of the piezoelectric element C0 is rapidly released through a diode D2 and the transistor Q1. Accordingly, a waveform having a sharp fall can be obtained, a stable drive of ink particles having a small diameter can be performed, a time constant can be varied since a resistance R4 is variable, and thus a particle velocity from each nozzle can be made equal. Moreover, no air bubbles penetrate into nozzles and thereby excellent printing is enabled, since the fall is sharp. |
