Image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorsNobuhiko Takekoshi, Takashi Hasegawa, Masahiro Inoue, Yoichi Kimura
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Abstract
The present invention provides an image forming apparatus comprising an image bearing member for bearing an image thereon, and a transfer device for transferring the image from the image bearing member to a recording material at a transfer station. Wherein a limit value of electric power supplied to the transfer device is changed between a case where an imaged portion of the image bearing member is positioned at the transfer station and a case where a non-imaged portion of the image bearing member is positioned at the transfer station.
Claims26
An image forming apparatus comprising:
- an image bearing member for bearing an image thereon;
- and
- transfer means for transferring the image from said image bearing member to a recording material at a transfer station, said transfer means performing a plurality of image transferring operations for a common recording material;
- wherein a limit value of electric power supplied to said transfer means is changed between a case where an imaged portion of said image bearing member is positioned at said transfer station and a case where a non-imaged portion of said image bearing member is positioned at said transfer station, and
- wherein the limit value for said imaged portion and said non-imaged portion is set so that the limit value in a last image transferring operation is greater than the limit value in a first image transferring operation, and the limit value in a certain transferring operation does not become larger than the limit value in a next transferring operation.
An image forming apparatus comprising:
- an image bearing member for bearing an image thereon;
- and
- transfer means for transferring the image from said image bearing member to a recording material at a transfer station, said transfer means performing a plurality of image transferring operations for a common recording material;
- wherein an amount of current applied to said transfer means is controlled under a constant current, and a maximum voltage value applied to said transfer means is set for every image transferring operation corresponding to the number of the image transferring operations.
An image forming apparatus comprising:
- an image bearing member for bearing an image thereon;
- and
- transfer means for transferring the image from said image bearing member to a recording material at a transfer station;
- wherein an amount of current applied to said transfer means is controlled under a constant current, and a maximum voltage value applicable to said transfer means is set smaller when a non-imaged portion of said image bearing member is in the transfer position than when an imaged portion of said image bearing member is in the transfer position.
An image forming apparatus comprising:
- an image bearing member for bearing an image thereon;
- and
- transfer means for transferring the image from said image bearing member to a recording material at a transfer station, said transfer means being controlled under a constant voltage;
- wherein a maximum current value applicable to said transfer means is set smaller when a non-imaged portion of said image bearing member is in the transfer station than when an imaged portion of said image bearing member is in the transfer station.
Dependencies are inferred from the claim text.