Patent ID: 6565186
Filing Date: 2003-05-20
Classification: B41J

Abstract:
In an ink jet head including plural groups of ejecting ports, each having a different flow rate coefficient, which are subjected to a suction recovery operation, the improvement wherein:an ink capacity of a first ink path communicated with a group of ejecting ports having a first flow rate coefficient is smaller than an ink capacity of a second ink path communicated with a group of ejecting ports having a second flow rate coefficient which is larger than said first flow rate coefficient, said flow rate coefficients differing from each other depending upon a difference in cross-sectional area of each ejecting port involved in each of said plural groups of ejecting ports, wherein, the first ink path and the second ink path have respective capacities so that, when said plural groups of ejecting ports are commonly subjected to a suction pressure, different amounts of ink contained in the first ink path and second ink path are sucked out integrally from said respective ink paths and expulsions of the different amounts of ink by suction are completed at a substantially same timing, and wherein each of said plural groups of ejecting ports ejects a different kind of ink.