Patent ID: 8696094
Filing Date: 2014-04-15
Classification: B41J

Abstract:
1. A method of ejecting liquid drops comprising: providing liquid under pressure sufficient to eject a liquid jet through a nozzle of a liquid chamber; providing input image data; providing a drop formation device associated with the liquid jet; providing a velocity modulation device; providing a charging device including: providing a first catcher and a second catcher, the first catcher being located on a first side of the liquid jet and the second catcher being located on a second side of the liquid jet; providing a deflection device; modulating the liquid jet using the drop formation device to cause portions of the liquid jet to break off into one or more clusters of drops traveling along a path, each cluster of drops separated on average by a drop cluster period, each cluster of drops including a first drop and a second drop; providing a charging waveform to the charge electrode of the charging device using the source of varying electrical potential of the charging device, the charging waveform including a first voltage state and a second voltage state having opposing polarities when compared to each other, the charging waveform having a period that is equal to the drop cluster period, the charging waveform being independent of the input image data; synchronizing the charging device with the drop formation device to produce a first charge state on the first drop of each drop cluster and produce a second charge state on the second drop of each drop cluster; causing the first drop having a first charge state to be deflected away from the path and toward the first catcher and the second drop having a second charge state being deflected away from the path and toward the second catcher using the deflection device; and modulating a relative velocity of the first drop and the second drop of a selected drop cluster using the velocity modulation device in response to input print data to cause the first drop and the second drop to form a merged drop traveling along the path, the merged drop having a third charge state that prevents the merged drop from being deflected to the first catcher by the deflection device and prevents the merged drop from being deflected to the second catcher by the deflection device.