| 摘要 |
PURPOSE:To accurately control deflection amounts of ink particles in an ink jet plotter wherein ink particles are deflected in multiple steps by an electric charge control system, by detecting ink particles with a recording surface. CONSTITUTION:Before starting the ejection of ink, sensors 11, 12 are positioned such that ink particles ejected against a deflection position detector 10, which is disposed outside recoring paper 8, impoinge, when the ink jet plotter is normally operated, upon the sensor 11 in a first deflection step and upon the sensor 12 in a final deflection step. The interval between the impinging of ink particles upon the sensor 11 and the impinging of ink particles upon the sensor 12 is set beforehand. Therefore, when the ink jet plotter is not normally operated, outputs from the sensors 11, 12 do not occur at predetermined points of time. In such a case, the outputs are fed back to charging electrodes to change the charging voltage and ascertain a normal operation thereof. Then, the printing of the recording paper 8 is started. |
