| 摘要 |
PURPOSE:To improve discharge stability by providing a composite wave form of two pulse shapes of an electric signal to be supplied to a piezoelectric element, and besides making it a pulse shape which enables the first pulse shape to be supplied and then the second pulse shape is supplied after passage of a specific time. CONSTITUTION:During a period in which an ink chamber 3 is initialized or which follows completion of the initialization, a negative pressure wave p1 makes a return trip through a nozzle after the lapse of 2l/c following the application of a negative pulse shape P1, and returns to the tip of the nozzle in the form of a positive pressure wave p1'. Timed to this, a voltage V3 and negative pulse P3 having a pulse width T1 are applied to provide a negative pressure wave p3. Consequently, the positive pressure wave p1 apparently disappears. After this, a positive pulse shape P2 is applied, and after the lapse of 4l/c, a positive pressure wave p2 shuttles twice through the nozzle. Therefore, after the lapse of 2l/c following the application of the positive pulse shape P2, a negative reflective wave p4' overlaps a positive reflective wave p2' and a pressure wave apparently goes out of sight. if a voltage V4 and a positive pulse shape P4 are applied. Thus high-precision printing can be effected. |
