PRINTER AND PRINTING METHOD FOR PRIMING INK JET PRINT HEAD

摘要

PROBLEM TO BE SOLVED: To obtain a printer in which a head can be primed without removing a print head from a carriage by expanding an air chamber with vent for coupling the gas source of the print head with a pressure higher than the atmospheric pressure and priming the head with a controlled ink flow into a nozzle. SOLUTION: An ink chamber 232 is provided in the body 201 of a print head 200 and a resistor 320 for vaporize a small quantity of adjacent ink through power supply related to each nozzle 312 is disposed on the underside of a substrate 318 in order to eject ink in an ejection chamber 316 as an ink drop 322 through the nozzle 312. Furthermore, a vent 210 communicating with the inside of a bag 208 in the body 201 is provided and sustained at a reference pressure during normal print. The vent 210 expands or contracts depending on the pressure difference between the back pressure in the chamber 232 and the ambient pressure communicating with the vent 210. When air is supplied from an air source to the bag 208, inner pressure of the chamber 232 increases to produce a priming ink flow to a nozzle 205.