Patent ID: 7973292

Claim:
A neutralizer comprising: a power supply circuit configured to generate a DC voltage; an output controlling circuit configured to convert the DC voltage generated by the power supply circuit to a high-frequency voltage with frequency equal to or higher than an audible frequency, and to output the resultant high-frequency voltage alternately to two output lines at regular intervals; a transforming circuit configured to raise the high-frequency voltage outputted from the output controlling circuit; a discharger including 2n (n is an integer equal to one or more) discharge needles configured to output positive ions in response to application of a DC high voltage with a positive polarity, and configured to output negative ions in response to application of a DC high voltage with a negative polarity, the discharge needles being disposed in the discharger while being divided into first and second groups each including n discharge needles; a polarity reversing circuit configured to convert the high-frequency high voltage outputted from the transforming circuit, to two rectangular-wave DC high voltages with different polarities during a certain period, to output the two DC high voltages respectively to the first and second groups in the discharger while reversing the polarities of the two DC high voltages at regular intervals; and an air blower configured to blow air from a windward side of the discharge needles, and to convey the positive and negative ions outputted from the 2n discharge needles, to a neutralization target object located on a leeward side of the discharge needles, wherein during a certain period, ions with one polarity are outputted from the first group in the discharger, whereas ions with the other polarity are outputted from the second group, and the polarity of the ions outputted from each of the groups is reversed at regular intervals.