INK SUPPLY MECHANISM OF ON-DEMAND TYPE INK JET PRINTER

摘要

PURPOSE:To always perform printing in a good state, by providing a supply pump for supplying ink into an ink sub-tank and a regular tank for absorbing pressure variation at the supply time of ink. CONSTITUTION:When an ink in an ink sub-tank 8 is reduced by the continuity of printing, the pressure of the air 9 sealed in said tank 8 is lowered. When a pressure sensor 10 senses that the pressure reaches set pressure or less, a supply pump 4 is driven on the basis of the output of the pressure sensor 10 to supply ink to the ink sub-tank 8. A regulator tank 5 for buffering the supply pressure difference of the ink due to the driving of the supply pump 4 is provided between the supply pump 4 and the ink sub-tank 8 and the ink is supplied to the ink sub-tank 8 by once supplying said ink through air.