| 摘要 |
PURPOSE:To contrive a higher reliability in detection of a phase, by controlling the level of a signal corresponding to each ink flow detected by a detecting circuit to within a predetermined range, in a cutting phase detector in which a detecting circuit for ink droplet separation phase is used in common for two or more of ink flows. CONSTITUTION:When detecting a phase,a phase-retrieving signal is sent from a charging circuit 19 to a charging electrode 5 in order to retrieve the phase of a head 10, an ink droplet is caused to impinge against a detecting electrode 11, and the quantity of charge is detected by the detecting circuit 13 through a shielded cable 12. When charge cannot be detected by the circuit 13, the phase of a charging signal is shifted, and the quantity of charge is detected. Thereafter, this operation is repeated, and when the quantity of charge is detected, a signal output is obtained from an ink separation phase detection discrimination output signal wire 14. Based on the output signal from the signal wire 15, it is discriminated by a controlling part 17 whether or not the output level is appropriate, and when the output level is not in the predetermined range, the output level is controlled to within the range. Then, a phase-retrieving signal is impressed on a head 10', and detection of ink droplet separation phase is conducted in the same manner as above. |
