B41J2/04575

Acoustic droplet ejection of non-newtonian fluids

Methods of ejecting droplets containing a non-Newtonian fluid by an acoustic droplet ejector can include applying a tone burst of focused acoustic energy to a fluid reservoir containing a non-Newtonian fluid at sufficient amplitude to effect droplet ejection according to a tone burst pattern. The tone burst pattern may include three discrete tone burst segments, the first tone burst segment having greater duration than the second and third segments, and third segment having greater duration than the second segment. The exact durations and amplitudes of the tone burst segments can be tuned to influence the ejection properties.

ACOUSTIC DROPLET EJECTION OF NON-NEWTONIAN FLUIDS

Methods of ejecting droplets containing a non-Newtonian fluid by an acoustic droplet ejector can include applying a tone burst of focused acoustic energy to a fluid reservoir containing a non-Newtonian fluid at sufficient amplitude to effect droplet ejection according to a tone burst pattern. The tone burst pattern may include three discrete tone burst segments, the first tone burst segment having greater duration than the second and third segments, and third segment having greater duration than the second segment. The exact durations and amplitudes of the tone burst segments can be tuned to influence the ejection properties.

Circuit and method for driving a print head

An electronic circuit for driving an individual print element in a print head is disclosed. The print head comprises an array of print elements, each print element having a piezo-electric actuator that is capable of generating an acoustic wave in an ink chamber of the print element, resulting in the ejection of an ink drop out of a nozzle that is in fluid connection with the ink chamber. The electronic circuit comprises a number of analog drivers for amplifying an output current at a voltage level in-between two source voltage levels, wherein the drivers can be switched into a tristate condition at a voltage level that does not equal one of the source voltage levels.