An ink is stored directly in an ink storage chamber. An printing head connecting portion is arranged on the bottom side of the ink storage chamber and an ink collector is arranged on the bottom side of the ink storage chamber and alongside on the upper face of the printing head connecting portion. The ink collector is provided with a plurality of vertical plate-like blade portions arranged in parallel in the axial direction so as to form an ink collector spaces therebetween, and the blade portions are provided with communicating notches in a line so that these communicating notches form an air/ink moving groove extending in the axial direction. One end of the air/ink moving groove is communicated with an air intake, and the other end thereof is communicated with the ink storage chamber. The air/ink moving groove moves the ink or the air between the ink storage chamber and the ink collector spaces or the air intake, when the pressure in said ink storage chamber becomes too high or too low.