The electrode needle of the plus and minus which discharges

摘要

PROBLEM TO BE SOLVED: To provide an ionizer equipped with a corona discharge monitoring function capable of speedily and efficiently carrying out ion generation by quickly excluding adverse effect of residual voltage at the time of polar switching of high-voltage power source, and capable of accurately monitoring an ion generation state.;SOLUTION: Direct-current high-voltage power sources 2a, 2b at a positive electrode side and a negative electrode side for impressing pulsated high voltage on electrode needles 1a, 1b in response to switching control of polarity, a residual voltage discharge circuit 8 connected between output terminals 3a, 3b of the both high-voltage power sources and discharging the residual voltage by the polarity before switching by being conducted merely for a period during which a potential difference between the electrodes is above a constant level at switching of the polarity, and detection resistors Ra, Rb for detecting ion-generating current flowing between the above electrode needles within a period in which the discharge circuit 8 is in a non-conductive state.;COPYRIGHT: (C)2008,JPO&INPIT