Device for testing the electrical charge state of ink droplets in the charging tunnel of an ink jet printer

摘要

An ink jet printer (e.g. Fig. 6) with amplitude-controlled charging contains, for the purpose of synchronisation of the charge signal supply to the droplet formation rhythm a device for testing the charged state which includes a metal element (7) which is connected directly to the ink liquid to be fed into a droplet discharging unit (1) and a capacitor (Cs) connected to this element. With correct ink droplet charging, a charge amount corresponding to the charge carried by the droplets (5) is stored in the capacitor, the capacitor voltage is measured and from this the charge state of the ink droplets determined. IMAGE