A.C. corona discharging device
AssigneeCanon Kabushiki Kaisha
InventorsHiroshi Tanaka, Shinkichi Takahashi, Touru Takahashi, Shusei Tsukada, Giichi Marushima
Life of this patent
Estimating the term…
Abstract
An A.C. corona discharging device for use in the process in which discharge and exposure are accomplished contemporaneously has insulating members disposed so as to surround the discharge wire or electrode and define the opening for projecting the image of an original. The potential gradient is increased, the discharge efficiency is improved and the flow of useless current which heretofore traveled through the shielding electrode is not encountered.
Claims8
An A.C. corona discharging system for applying a corona discharge to a photoconductive member having a conductive backing, and for contemporaneously projecting an optical image upon the member, comprising in combination:
- means for connecting the conductive backing of the member to a point of reference potential;
- an electrode, and means for supporting said electrode at a position spaced from said photoconductive member on the side remote from said backing, wherein said electrode and said photoconductive member are relatively movable for scanning the surface of the latter;
- means for connecting a source of alternating current voltage between said point of reference potential and said electrode for establishing a corona discharge between said electrode and said photoconductive member;
- and insulating material supported at a position spaced from said photoconductive member and surrounding said electrode to define an optical path for the projection of said image therethrough upon said photoconductive member, wherein said material is disposed to become oppositely charged during alternate half cycles of said source voltage for enhancing the corona discharge.
An A.C. corona discharging device for applying a corona discharge to a photoconductive member having a conductive backing, and for contemporaneously projecting an optical image upon the member, comprising in combination:
- means for connecting the conductive backing of the member to a point of reference potential;
- electrode means and means for supporting said electrode means at a position spaced from said photoconductive member on the side remote from said backing, wherein said electrode means and said photoconductive member are relatively movable for scanning the surface of the latter;
- means for connecting a source of alternating current voltage between said point of reference potential and said electrode means for establishing a corona discharge between said electrode means and said photoconductive member;
- and side wall members having insulating material supported at a position spaced from said photoconductive member and surrounding said electrode means to define an optical path for the projection of said image therethrough upon said photoconductive member, wherein said material is disposed to become oppositely charged during alternate half cycles of said source voltage for enhancing the corona discharge.
Dependencies are inferred from the claim text.