Image forming apparatus

Patent metadata

Field	Value
Publication number	US-9829845-B2
Application number	US-201615008828-A
Country	US
Kind code	B2
Filing date	Jan 28, 2016
Priority date	Aug 26, 2009
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

An image forming apparatus includes a controller configured to execute a discharging operation for discharging a toner from a developing device onto an image bearing member in a region corresponding to an interval between a recording material and a subsequent recording material in a continuous image forming job. The controller executes the discharging operation on the basis of integral information based on a relationship of a predetermined deterioration threshold with a value correlating with an amount of toner consumption. The controller changes the relationship based on a detected temperature upon toner consumption, and the controller changes the relationship so that when a temperature obtained on the basis of detected information is not less than a predetermined temperature, execution of the discharging operation is promoted more than when the obtained temperature is less than a predetermined temperature.

First claim

What is claimed is:

1. An image forming apparatus comprising:
an image bearing member;
a developing device configured to develop a latent image on said image bearing member to form a toner image using a toner;
a transferring device configured to transfer the toner image on said image bearing member onto a recording material;
a temperature sensor configured to detect a temperature; and
a controller configured to execute a discharging operation for discharging a toner from said developing device onto said image bearing member in a region corresponding to an interval between a recording material and a subsequent recording material in a continuous image forming job for continuously forming an image on a plurality of recording materials on the basis of a value correlating with an amount of toner consumption obtained every predetermined interval and a detection result of said temperature sensor,
wherein said controller executes the discharging operation on the basis of integral information obtained by integration of information determined based on a relationship of a predetermined deterioration threshold with the value correlating with an amount of toner consumption,
wherein said controller is configured to change the relationship of the predetermined deterioration threshold with the value correlating with an amount of toner consumption, based on the detection result of said temperature sensor detected upon the toner consumption, and
wherein said controller changes the relationship so that when a temperature obtained on the basis of information detected by said temperature sensor is not less than a predetermined temperature, execution of the discharging operation is promoted more than when the obtained temperature is less than a predetermined temperature.

2. An image forming apparatus according to claim 1 , wherein said controller changes the predetermined deterioration threshold on the basis of the information detected by said temperature sensor.

3. An image forming apparatus according to claim 1 , wherein the value correlating with an amount of toner consumption is a video count value.

4. An image forming apparatus according to claim 1 , wherein said controller executes the discharging operation when the integral information reaches a predetermined execution threshold and resets the integral information when the discharging operation is executed.

5. An image forming apparatus according to claim 1 , wherein the predetermined interval is an interval in which image formation of a predetermined print number is executed.

6. An image forming apparatus according to claim 1 , wherein the information determined based on the relationship is obtained on the basis of a comparison between a video count value obtained every predetermined interval and the predetermined deterioration threshold.

7. An image forming apparatus according to claim 1 , wherein the information determined based on the relationship is a video count value when the video count value obtained every predetermined interval is smaller than the predetermined deterioration threshold.

8. An image forming apparatus comprising:
an image bearing member;
a developing device configured to develop a latent image on said image bearing member to form a toner image using a toner;
a transferring device configured to transfer the toner image on said image bearing member onto a recording material;
a temperature sensor configured to detect a temperature; and
a controller configured to execute a discharging operation for discharging a toner from said developing device onto said image bearing member in a region corresponding to an interval between a recording material and a subsequent recording material in a continuous image forming job for continuously forming an image on a plurality of recording materials on the basis of a value correlating with an amount of toner consumption obtained every predetermined interval and a detection result of said temperature sensor,
wherein said controller executes the discharging operation on the basis of integral information obtained by integration of information determined based on a relationship of a predetermined deterioration threshold with the value correlating with an amount of toner consumption, and
wherein said controller controls the discharging operation in the following manner:
(i) in a case where a temperature obtained on the basis of information detected by said temperature sensor is a first temperature, said controller executes the discharging operation on the basis of the value correlating with an amount of toner consumption when the value correlating with an amount of toner consumption is less than a first predetermined amount and does not execute the discharging operation when the value correlating with an amount of toner consumption is not less than the first predetermined amount, and
(ii) in a case where a temperature obtained on the basis of information detected by said temperature sensor is a second temperature higher than the first temperature, said controller executes the discharging operation on the basis of the value correlating with an amount of toner consumption when the value correlating with an amount of toner consumption is less than a predetermined amount larger than the first predetermined amount and does not execute the discharging operation when the value correlating with an amount of toner consumption is not less than the second predetermined amount.

9. An image forming apparatus according to claim 8 , wherein said controller is configured to change the relationship of the predetermined deterioration threshold with the value correlating with an amount of toner consumption, based on the detection result of said temperature sensor detected upon the toner consumption, and
wherein said controller changes the relationship so that when a temperature obtained on the basis of information detected by said temperature sensor is not less than a predetermined temperature, execution of the discharging operation is promoted more than when the obtained temperature is less than a predetermined temperature.

10. An image forming apparatus according to claim 8 , wherein said controller changes the predetermined deterioration threshold on the basis of the information detected by said temperature sensor.

11. An image forming apparatus according to claim 8 , wherein the value correlating with an amount of toner consumption is a video count value.

12. An image forming apparatus according to claim 8 , wherein said controller executes the discharging operation when the integral information reaches a predetermined execution threshold and resets the integral information when the discharging operation is executed.

13. An image forming apparatus according to claim 8 , wherein the predetermined interval is an interval in which image formation of a predetermined print number is executed.

14. An image forming apparatus according to claim 8 , wherein the information determined based on the relationship is obtained on the basis of a comparison between a video count value obtained every predetermined interval and the predetermined deterioration threshold.

15. An image forming apparatus according to claim 8 , wherein the information determined based on the relationship is a video count value when the video count value obtained every predetermined interval is smaller than the predetermined deterioration threshold.

16. An image forming apparatus comprising:
an image bearing member;
a developing device configured to develop a latent image on said image bearing member to form a toner image using a toner;
a transferring devi

Assignees

• Canon Kk

Inventors

• Nose Katsuya

Classifications

• G03G15/556 Primary

  for toner consumption, e.g. pixel counting, toner coverage detection or toner density measurement · CPC title

• G03G15/065

  Arrangements for controlling the potential of the developing electrode · CPC title

• G03G15/0844 Primary

  Arrangements for purging used developer from the developing unit · CPC title

• G03G2215/00084

  the characteristic being the temperature · CPC title

• G03G21/0094

  fatigue treatment of the photoconductor · CPC title