Image forming apparatus with conductive member adjoining light irradiating portion
AssigneeCanon Kabushiki Kaisha
InventorsYoshiyuki Komiya, Atsushi Takeda, Fumiteru Gomi, Kouichi Hashimoto, Kenichi Shibuya, Shuichi Kadota
Life of this patent
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Abstract
Toner particles fly off from a photosensitive drum to an exposure light emitting portion by a change of electric potential distribution on the photosensitive drum caused by image exposure in a following process. This causes a poor copy of an image by adhering the toner particles to the exposure light emitting portion. This phenomena affects a tandem type of copiers with multi-stations including photosensitive drums and exposure light emitting positions. An apparatus capable of suppressing toner adhesion to an exposure is provided to solve the above problem.
Claims27
An image forming apparatus comprising:
- a photosensitive member for bearing a toner image;
- charging means for charging the photosensitive member and bringing back the residual toner charged in a same polarity as a polarity of the charging means;
- image exposing means for exposing the photosensitive member in accordance with an image information, said image exposing means having a light irradiating portion facing the photosensitive member;
- a conductive member disposed adjacent to the light irradiating portion;
- and
- voltage application means for applying a voltage to the conductive member,
- wherein the voltage applied by the voltage application means forms an electric field between the photosensitive member and the conductive member to push said toner brought back to the photosensitive member to move in a direction of the photosensitive member.
An image forming apparatus comprising:
- a photosensitive member for bearing a toner image;
- charging means for charging the photosensitive member, collecting residual toner on the photosensitive member and bringing back the residual toner charged in a same polarity as a charged polarity of the charging means;
- image exposing means for exposing the photosensitive member in accordance with an image information, said image exposing means having a light irradiating portion facing the photosensitive member;
- a conductive member disposed adjoining the light irradiating portion;
- and
- voltage application means for applying a voltage to the conductive member, the voltage having a same polarity as the charged polarity,
- wherein the voltage application means applies the voltage during the time the conductive member faces the charged photosensitive member.
An image forming apparatus comprising:
- a photosensitive member;
- image exposing means for exposing said photosensitive member in accordance with an image information, said image exposing means having a light irradiation portion facing said photosensitive member;
- a conductive member adjoining said light irradiation portion;
- and
- voltage application means for applying a voltage to said conductive member,
- wherein said voltage application means applies a voltage to said conductive member in synchronism with a timing for driving said photosensitive member.
An image forming apparatus comprising:
- a photosensitive member;
- image exposing means for exposing the photosensitive member in accordance with an image information, said image exposing means having a light irradiating portion facing the photosensitive member;
- a conductive member adjoining the light irradiating portion;
- environment detection means for detecting a temperature and a humidity within said apparatus;
- and
- voltage application means for applying a voltage to the conductive member,
- wherein the voltage application means applies a voltage to the conductive member in correspondence with output of the environmental detection means.
An image forming apparatus comprising:
- a photosensitive member;
- charging means for charging said photosensitive member;
- image exposing means for exposing said photosensitive member in accordance with image information, said image exposing means having a light irradiation portion facing said photosensitive member;
- a conductive member adjoining said light irradiation portion, said conductive member having two end portions,
- wherein both of said two end portions of said conductive member along a longitudinal direction of said photosensitive member are disposed outside of a charging region of said photosensitive member.
Dependencies are inferred from the claim text.