초록 ▼

A mechanically balanced pulsed ink droplet mechanism includes a disk or ring of piezoelectric ceramic material positioned within a metal ring of rectangular cross section having an annular channel in its inner surface that is sealed by a thin metal diaphragm to form an annular ink chamber. The piezo

A mechanically balanced pulsed ink droplet mechanism includes a disk or ring of piezoelectric ceramic material positioned within a metal ring of rectangular cross section having an annular channel in its inner surface that is sealed by a thin metal diaphragm to form an annular ink chamber. The piezoelectric transducer is in mechanical engagement with the inner surface of the annular diaphragm, but the ink is electrically insulated from the ceramic. A voltage pulse applied to opposite sides of the disk causes it to expand and eject a droplet of ink from the printing orifice. The ink chamber is shallow and has a ratio of cross section to wetted perimeter or hydraulic radius approximately equal to the diameter of the orifice which quickly damps oscillations resulting from the ejection of each droplet of ink and permitting higher speed operation. The ink chamber is sealed without the use of compliant materials resulting in minimal additional compliance to the liquid. The construction causes the displacement produced by the transducer to be efficiently transmitted to the ink chamber, producing droplets with improved definition at greater efficiencies.

대표청구항 ▼

An ink jet printer head system comprising a printer head having a housing having therein an annular channel, an annular diaphragm secured to said housing and forming with said channel an annular ink reservoir, said housing including an inlet port and an outlet orifice each communicating with said re

An ink jet printer head system comprising a printer head having a housing having therein an annular channel, an annular diaphragm secured to said housing and forming with said channel an annular ink reservoir, said housing including an inlet port and an outlet orifice each communicating with said reservoir, and a piezoelectric transducer comprising piezoelectric material having an annular surface in mechanical engagement with said diaphragm, and first and second electrodes on opposite sides of said piezoelectric material.