Ac corona discharger

Claim 2

An AC corona discharging device, comprising; a shielding member; a corona discharging member placed within said shielding member; an opposing electrode mounted opposedly to said corona discharging member; an AC high voltage source having a pair of output terminals; and means for coupling said pair of high voltage source terminals respectively to said corona discharging member and said electrode, said coupling means including means for passing the positive component of the voltage from said AC high voltage source, and for partially decreasing only the negative component of the voltage imparted to said corona discharging member from said AC high voltage source.

Claim 3

An AC corona discharging device, comprising; a shielding member; a corona discharging member placed within said shielding member; an opposing electrode mounted opposedly to said corona discharging member; an AC high voltage source having a pair of output terminals; and means for coupling said pair of high voltage source terminals respectively to said corona discharging member and said electrode, said coupling means including means for passing the positive component of the voltage from said AC high voltage source, and for partially decreasing only the negative component of the voltage imparted to said corona discharging member from said AC high voltage source.

Claim 4

An AC corona discharging device, comprising; a shielding member; a corona discharging member placed within said shielding member; an opposing electrode mounted opposedly to said corona discharging member; an AC high voltage source having a pair of output terminals; and means for coupling said pair of high voltage source terminals respectively to said corona discharging member and said electrode, said coupling means including means for passing the positive component of the voltage from said AC high voltage source, and for partially decreasing only the negative component of the voltage imparted to said corona discharging member from said AC high voltage source.

Claim 5

An AC corona discharging device as defined in claim 1, wherein said means for decreasing said voltage includes a resistor.

Claim 6

An AC corona discharging device as set forth in claim 1, in which said coupling means includes a conductor connected between one of said source terminals and said opposing electrode, said means for decreasing only the negative component of the voltage being connected between the other said source terminal and said corona discharging member, wherein said means for decreasing only said negative component of the voltage comprises a first diode coupled between said other source terminal and said discharging member to pass the positive component of said voltage to said discharging member, and further comprises a series combination of a second diode and a resistor, said series combination being connected in parallel with said first diode, and said second diode being arranged to pass said negative voltage component.

Claim 7

An AC corona discharging device as defined in claim 1, wherein said opposing electrode is disposed below said discharging member, and wherein the upper portion of said shielding member is optically open.

Claim 8

In an AC corona discharging device including a shielding member, a corona discharging member placed within the shielding member, and an opposing electrode mounted opposedly to the corona discharging member, the improvement comprising: an AC high voltage source including a transformer having a primary winding and first and second secondary windings, said first secondary winding having one end connected to said discharging member, and said second secondary winding having one end connected to said electrode; a diode connected between the other ends of said secondary windings with its cathode connected to said other end of said first secondary winding; and a capacitor electrically connected from said cathode to said discharging member, whereby the positive component of the AC voltage applied between said discharging member and said electrode is increased with respect to the negative component of the AC voltage applied therebetween.

Claim 9

In an AC corona discharging device including a shielding member, a corona discharging member placed within the shielding member, and an opposing electrode mounted opposedly to the corona discharging member, the improvement comprising: an AC high voltage source including a transformer having a primary winding and first and second secondary windings, said first secondary winding having one end connected to said discharging member, and said second secondary winding having one end connected to said electrode; a diode connected between the other ends of said secondary windings with its cathode connected to said other end of said first secondary winding; and a capacitor electrically connected from said cathode to said discharging member, whereby the positive component of the AC voltage applied between said discharging member and said electrode is increased with respect to the negative component of the AC voltage applied therebetween.