Image forming apparatus and control method for controlling photoconductor film thickness detection

Patent metadata

Field	Value
Publication number	US-10496002-B2
Application number	US-201916249113-A
Country	US
Kind code	B2
Filing date	Jan 16, 2019
Priority date	Mar 15, 2018
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

An image forming apparatus includes a photoconductor, a power supply, and circuitry. The power supply is configured to apply a charging voltage to the photoconductor. The circuitry is configured to control film thickness detection of detecting a charging current corresponding to the charging voltage to detect a film thickness of a surface of the photoconductor. The circuitry is further configured to determine a sampling period taken to detect the charging current; calculate a variation in the charging current detected; and determine whether the variation is greater than a threshold. The circuitry is configured to: determine the sampling period according to a determination result as to whether the variation is greater than the threshold; and sample the charging current for the sampling period determined, on a subsequent film thickness detection control.

First claim

What is claimed is:

1. An image forming apparatus comprising:
a photoconductor;
a power supply configured to apply a charging voltage to the photoconductor; and
circuitry configured to:
control film thickness detection of detecting a charging current corresponding to the charging voltage to detect a film thickness of a surface of the photoconductor;
determine a sampling period taken to detect the charging current;
calculate a variation in the charging current detected; and
determine whether the variation is greater than a threshold,

the circuitry being configured to:
determine the sampling period according to a determination result as to whether the variation is greater than the threshold; and
sample the charging current for the sampling period determined, on a subsequent film thickness detection control.

2. The image forming apparatus according to claim 1 , further comprising a memory that is configured to store information including a past detection result of the charging current and a past variation in the charging current,
wherein the circuitry is configured to calculate the variation with a current charging current detected and the information stored in the memory.

3. The image forming apparatus according to claim 1 ,
wherein the circuitry is configured to calculate the variation based on an average value of the charging current sampled.

4. The image forming apparatus according to claim 1 ,
wherein the circuitry is configured to calculate the variation based on a difference value between a maximum value and a minimum value of the charging current sampled.

5. The image forming apparatus according to claim 1 ,
wherein the circuitry is configured to determine the threshold based on the film thickness detected on the film thickness detection.

6. The image forming apparatus according to claim 1 ,
wherein the circuitry is configured to determine the threshold based on environment information including temperature and humidity information.

7. A control method employed by an image forming apparatus that includes a photoconductor, the method comprising:
controlling film thickness detection of detecting a charging current corresponding to a charging voltage applied to the photoconductor, to detect a film thickness of a surface of the photoconductor;
first determining a sampling period taken to detect the charging current;
calculating a variation in the charging current detected; and
second determining whether the variation is greater than a threshold,
the first determining including determining the sampling period according to a determination result as to whether the variation is greater than the threshold,
the controlling including sampling the charging current for the sampling period determined, on a subsequent film thickness detection control.

8. The control method according to claim 7 , further comprising storing, in a memory, information including a past detection result of the charging current and a past variation in the charging current,
wherein the calculating includes calculating the variation with a current charging current detected and the information stored in the memory.

9. The control method according to claim 7 ,
wherein the calculating includes calculating the variation based on an average value of the charging current sampled.

10. The control method according to claim 7 ,
wherein the calculating includes calculating the variation based on a difference value between a maximum value and a minimum value of the charging current sampled.

11. The control method according to claim 7 ,
wherein the second determining includes determining the threshold based on the film thickness detected on the film thickness detection.

12. The control method according to claim 7 ,
wherein the second determining includes determining the threshold based on environment information including temperature and humidity information.

Assignees

• Sakuraba Jyunya
• Minami Shinji
• Ricoh Co Ltd

Inventors

• Sakuraba Jyunya
• Minami Shinji

Classifications

• G03G15/75

  Details relating to xerographic drum, band or plate, e.g. replacing, testing (electrographic recording members per se G03G5/00) · CPC title

• G03G15/553

  Monitoring or warning means for exhaustion or lifetime end of consumables, e.g. indication of insufficient copy sheet quantity for a job · CPC title

• G03G15/5037 Primary

  the characteristics being an electrical parameter, e.g. voltage · CPC title

• G03G15/0266 Primary

  Arrangements for controlling the amount of charge · CPC title