US 8,526,865 B2Granted

Developer supply apparatus and image forming apparatus

AssigneeBrother Kogyo Kabushiki Kaisha

InventorKenjiro Nishiwaki

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Abstract

An image forming device is provided which includes a developer carrying body and a developer supply device to supply a developer to the developer carrying body. The developer supply device includes a plurality of transfer electrodes, and a transfer voltage applying unit to apply traveling-wave shaped transfer voltages to the plurality of transfer electrodes. The developer includes a fine particle charged in a predetermined polarity and a fine particle charged in a polarity opposite to the predetermined polarity. The transfer voltage applying unit is configured to apply the transfer voltages having waveforms, which make a fly height of the fine particle charged in the predetermined polarity higher than a fly height of the fine particle charged in the opposite polarity, to the plurality of transfer electrodes.

Claims5

Dependent claims

An image forming device comprising:

a developer carrying body having a developer supporting surface configured to support developer including a plurality of fine particles;
and
a developer supply device configured to supply the developer to the developer carrying body, while transferring the developer along a developer transfer path,
wherein the developer supply device comprises:
a plurality of transfer electrodes arranged along a developer transfer surface facing the developer transfer path, in a developer transfer direction;
and
a transfer voltage applying unit which is electrically connected to the plurality of transfer electrodes and is configured to apply traveling-wave shaped transfer voltages to the plurality of transfer electrodes,
wherein the developer comprises a fine particle charged in a positive polarity and a fine particle charged in an negative polarity, and
wherein the transfer voltage applying unit is configured to apply the traveling-wave shaped transfer voltages having waveforms, the waveforms making a fly height of the fine particle charged in the positive polarity higher than a fly height of the fine particle charged in the negative polarity, to the plurality of transfer electrodes, and the waveforms being respectively shaped such that a rising edge is steeper than a falling edge, to the plurality of transfer electrodes.

6 more elements

A developer supply device configured to supply developer to a developer carrying body having a developer supporting surface configured to support the developer, while transferring the developer along a developer transfer path, the developer supply device comprising:

a plurality of transfer electrodes arranged along a developer transfer surface facing the developer transfer path, in a developer transfer direction;
and
a transfer voltage applying unit which is electrically connected to the plurality of transfer electrodes and is configured to apply traveling-wave shaped transfer voltages to the plurality of transfer electrodes,
wherein the developer comprises a fine particle charged in a positive polarity and a fine particle charged in opposite negative polarity,
wherein the transfer voltage applying unit is configured to apply the traveling-wave shaped transfer voltages having waveforms, the waveforms making a fly height of the fine particle charged in the positive polarity higher than a fly height of the fine particle charged in the negative polarity, to the transfer electrodes,
wherein the waveforms being respectively shaped such that a rising edge is steeper than a falling edge, to the plurality of electrodes.

3 more elements

Dependencies are inferred from the claim text.