| 摘要 |
PURPOSE:To make the negative suction force in an ink jet head constant to prevent the generation air bubbles in the head, by sucking the ink of the ink jet head after the residual ink in a suction chamber is discharged. CONSTITUTION:When a piston 12 is pushed down to a direction A, ink remaining in a suction chamber 17 is sucked by slight negative pressure generated by the movement of a contact part 15 to an elastic sheet and discharged to a discharge chamber 18 through a discharge hole 12A. By this mechanism, the volume of the suction chamber 17 is made constant in the succeeding negative pressure generating process and negative suction force due to volume expansion is made constant. In the next step, when the piston 12 is further pushed down, ink is sucked from an ink jet nozzle through the suction port 21 in the suction chamber 17 to be emitted and restored. |
