THERMAL INK JET PRINT HEAD MAINTENANCE BLADE INTERPOSER
Original Publication Date: 1991-Feb-28
Included in the Prior Art Database: 2004-Apr-05
Xerox Disclosure Journal
Many thermal ink jet print head devices are drop-on-demand type. In a full-page width print head, it is not uncommon for an individual nozzle to go unfired during the course of printing an entire document. Such a situation can lead to clogging of the jet nozzle. Typically, inks are designed having a 30 to 100 second latency period, that is, the period of time between jet discharge when the ink remains in a flowable liquid state before drying to a consistency that is susceptible to clogging. An improvement in thermal ink jet operating performance by reducing undesired clogging may be achieved by incorporating a retractable blade or shield that acts as a surrogate receiver that is intermittently interposed between the full-width ink jet print head and the document print target area. The jet nozzles are briefly and simultaneously discharged into the blade. The blade is retracted thereby effectively removing the flushed material and restoring the ink jet print head to a print-ready state. A number of mechanical configurations which coordinate the interposition/retraction of the blade with printing activities are readily accomplished.