Image forming apparatus, control method, and non-transitory recording medium

Patent metadata

Field	Value
Publication number	US-12130563-B2
Application number	US-202318355492-A
Country	US
Kind code	B2
Filing date	Jul 20, 2023
Priority date	Aug 9, 2022
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

An image forming apparatus includes an image bearer, a power source to generate a voltage, a voltage applying device facing the image bearer, the voltage applying device being applied with the voltage, and circuitry to control the voltage of the power source. The circuitry switches the voltage between a first direct current (DC) bias and a second DC bias different from the first DC bias, and changes the first DC bias in accordance with a speed of the image bearer, based on a DC component of a current flowing between the power source and the image bearer during application of the second DC bias.

First claim

The invention claimed is:

1. An image forming apparatus comprising:
an image bearer;
a power source that generates a voltage;
a voltage applying device facing the image bearer, the voltage applying device being applied with the voltage; and
circuitry configured to control the voltage of the power source, the circuitry being configured to:
switch the voltage between a first direct current (DC) bias and a second DC bias different from the first DC bias; and
change the first DC bias in accordance with a speed of the image bearer, based on a DC component of a current flowing between the power source and the image bearer during application of the second DC bias.

2. The image forming apparatus according to claim 1 , wherein the first DC bias is set such that an absolute value of the first DC bias decreases as the speed increases and the absolute value of the first DC bias increases as the speed decreases.

3. The image forming apparatus according to claim 1 , wherein an absolute value of the first DC bias is larger than an absolute value of the second DC bias.

4. The image forming apparatus according to claim 1 , wherein the circuitry is configured to detect a film thickness of a surface layer of the image bearer in accordance with the current.

5. The image forming apparatus according to claim 1 , wherein the circuitry is configured to change the first DC bias in accordance with a film thickness of a surface layer of the image bearer.

6. The image forming apparatus according to claim 1 , wherein the circuitry is configured to:
leave the first DC bias unchanged in response to the first DC bias having an appropriate value suitable for the speed of the image bearer; and
change the first DC bias in response to the first DC bias not having an appropriate value suitable for the speed of the image bearer.

7. The image forming apparatus according to claim 1 , wherein the circuitry is configured to:
leave the first DC bias unchanged in response to the first DC bias having an appropriate value suitable for a film thickness of a surface layer of the image bearer; and
change the first DC bias in response to the first DC bias not having an appropriate value suitable for the film thickness of the surface layer of the image bearer.

8. The image forming apparatus according to claim 1 , wherein the circuitry is configured to detect a surface potential of the image bearer in accordance with at least one of the current or a film thickness of a surface layer of the image bearer.

9. The image forming apparatus according to claim 8 , wherein the circuitry is configured to correct a DC bias for image formation, based on the detected surface potential of the image bearer.

10. The image forming apparatus according to claim 1 , wherein the power source applies an oscillating voltage to the voltage applying device, the oscillating voltage being a superimposition of a DC bias and an AC bias.

11. A control method for controlling an image forming apparatus, the control method comprising:
switching a voltage to be applied to a voltage applying device between a first direct current (DC) bias and a second DC bias different from the first DC bias, the voltage applying device facing an image bearer;
detecting a DC component of a current flowing between a power source that generates the voltage and the image bearer during application of the second DC bias; and
changing the first DC bias in accordance with a speed of the image bearer.

12. A non-transitory recording medium storing a plurality of instructions which, when executed by one or more processors, causes the processors to perform a control method for controlling an image forming apparatus, the control method comprising:
switching a voltage to be applied to a voltage applying device between a first direct current (DC) bias and a second DC bias different from the first DC bias, the voltage applying device facing an image bearer;
detecting a DC component of a current flowing between a power source that generates the voltage and the image bearer during application of the second DC bias; and
changing the first DC bias in accordance with a speed of the image bearer.

Assignees

• Yamamoto Yuusuke
• Ricoh Co Ltd

Inventors

• Yamamoto Yuusuke

Classifications

• G03G15/0266 Primary

  Arrangements for controlling the amount of charge · CPC title