Corona device.

摘要

A support member in the form of a glass rod carried four axially aligned corona electrodes 86 and a conductive foil 102 with a conductive biasing member in the form of a wire 98 wrapped around both the support member, the electrodes and the foil to form a coil. The foil 102 ensures continuity should the wire 98 fail locally. The rod 60 has a handle 70 which is rotatable in a mounting block 64 so as to bring any selected one of the electrodes into an operational position in which it is connected to an electrical source.