| 摘要 |
PURPOSE:To elevate the printing accuracy with a less effect of interference vibration by applying voltage pulses to an ink gun for injecting ink and the ink gun adapted to refuse the injection of a part or the whole of ink at the same timing with a different waveform in the opposite direction to each other. CONSTITUTION:When a drive voltage pulse is applied to a piezo electric element 8, a pulse is applied to a piezo-electric element 8' in the opposite direction to the drive voltage pulse with a lower voltage to reduce the pressure variation in an ink gun 4 to such an extent as to at least keep the meniscus of a nozzle 6 from breaking. In other words, as soon as a drive pulse 12 is applied to the piezo-electric element 8, a non-drive pulse 13 is done to the piezo-electric element 8'. The pressure inside an ink gun 2 forms a waveform 14 but the pressure change in the ink gun 4 reduces as shown by the waveform 15 because the effect of the piezo-electric element 8' can be cancelled by the effect of the piezo- electric element 8. This never allows the pressure change to overcome the surface tension of the ink in the nozzle 6 and thus the meniscus only oscillates but it kept from breaking. |
