US 6,712,455 B2 · Piezoelectrically driven printhead array

Abstract

A printhead includes a common ink chamber or reservoir bounded on one side by a membrane having nozzle apertures. The membrane forms a print face of the printhead. Piezoelectric elements (piezos) are located on the membrane near the nozzles. The piezos flex segments of the membrane surrounding the nozzles to eject ink droplets from the nozzle apertures. Ribs are also provided on the membrane and define boundaries of the membrane segments corresponding to the nozzles. The ribs can isolate each nozzle from the other nozzles, in two ways. First, the ribs act as stiffeners so that when piezos attached to one membrane segment flex that membrane segment, the other membrane segments are not significantly flexed. Second, when the ribs are provided on an interior surface of the membrane, they deflect the pressure pulse in the ink fluid from a flexing membrane segment, upwards, away from adjacent membrane segments/nozzles.

Claims20

Dependent claims

A printhead, comprising:

a print fluid reservoir;
a membrane forming a side of the reservoir;
a plurality of nozzle apertures in the membrane;
for each nozzle aperture, ribs attached to the membrane to isolate a segment of the membrane surrounding the nozzle aperture from movement of the membrane at a different location, wherein the ribs extend into the reservoir a distance less than four times a thickness of the membrane;
and
for each nozzle aperture, at least one piezoelectric element attached to the isolated segment of the membrane surrounding the nozzle aperture.

3 more elements

Dependencies are inferred from the claim text.

Piezoelectrically driven printhead array

Life of this patent

Piezoelectrically driven printhead array

Life of this patent

Abstract

Claims20