Patent ID: 7938516

Claim:
A continuous inkjet system for selectively depositing liquid droplets upon a surface, the system comprising: a liquid chamber including a nozzle, the liquid chamber containing liquid under pressure sufficient to produce a liquid jet through the nozzle; a source of varying electrical potential having a periodicity providing cycles each having a relatively high-voltage phase and a relatively low-voltage phase; a stimulation device operatively associated with the liquid jet, the stimulation device being responsive to respective different types of stimulation signals and operable to produce a modulation in the liquid jet to selectively control droplet break off relative to phases of the cycle of the source, a first liquid droplet from the liquid jet having a first break off phase relative to a cycle of the source and a second liquid droplet from the liquid jet having a second break off phase relative to a cycle of the source, the first break off phase and the second break off phase having a difference such that the first break off phase coincides with the relatively high-voltage phase and the second break off phase coincides with the relatively low-voltage phase; and a deflection mechanism including a charge electrode electrically connected to the source of varying electrical potential, the charge electrode being operable to produce a charge differential between the first liquid droplet and the second liquid droplet, and the deflection mechanism being operable to cause trajectories of the first liquid droplet and the second liquid droplet to diverge so that a trajectory of one droplet of the first and second liquid droplets causes the one droplet to be directed for collection and prevented from depositing on the surface and a trajectory of the other droplet of said first and second liquid droplets causes the other droplet to be directed for depositing upon the surface and wherein the electrical potential on the charge electrode varies with said periodicity and is independent of types of stimulation signals used to determine whether a droplet is to travel in accordance with the trajectory of the first liquid droplet or the trajectory of the second liquid droplet.