Image forming apparatus

Patent metadata

Field	Value
Publication number	US-10345750-B2
Application number	US-201715855828-A
Country	US
Kind code	B2
Filing date	Dec 27, 2017
Priority date	Dec 12, 2014
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

An image forming apparatus includes: an image bearing member, a developing device, and a controller configured to execute an operation in a forced consumption mode. The controller includes a difference calculating portion, an integrating portion, and a flag. In a case where the flag is set when a predetermined time is elapsed after the integrated value exceeds the predetermined threshold, the image formation on the predetermined number of the recording materials is effected and then the controller executes the operation in the forced consumption mode, and in a case where the flag is reset when the predetermined time is elapsed after the integrated value exceeds the predetermined threshold, the image formation on the predetermined number of the recording materials is effected and then the controller continues an image forming operation without executing the operation in the forced consumption mode.

First claim

What is claimed is:

1. An image forming apparatus capable of executing a continuous image forming job for continuously forming images on a plurality of recording materials comprising:
an image forming unit including an image bearing member and a developing device configured to develop, with toner, an electrostatic latent image formed on said image bearing member; and
a controller configured to cause said image forming unit to execute an operation in a toner supplying mode in which the continuous image forming job is interrupted, and in a state that the continuous image forming job is interrupted, the electrostatic latent image formed on said image bearing member is developed by said developing device and then the toner is supplied to said image bearing member,
wherein said controller is capable of causing said image forming unit to execute the operation in the toner supplying mode on the basis of information on an amount of the toner consumed by formation of the images formed on the plurality of recording materials in the continuous image forming job,
wherein said controller
(i) causes said image forming unit to execute the operation in the toner supplying mode with an end of execution of formation of the images on the recording materials in a first number of sheets in the continuous image forming job in a case that an amount of the toner consumed by formation of the images formed on the recording materials in the first number of sheets in the continuous image forming job is a first predetermined amount and that the continuous image forming job is completed by the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job,
(ii) causes said image forming unit to execute the operation in the toner supplying mode with an end of execution of formation of the images on the recording materials in a second number of sheets in the continuous image forming job in a case that the amount of the toner consumed by formation of the images formed on the recording materials in the first number of sheets in the continuous image forming job is the first predetermined amount and the continuous image forming job is not completed by the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job and that an amount of the toner consumed by formation of the images formed on the recording materials in the second number of sheets subsequent to the recording materials in the first number of sheets in the continuous image forming job is not more than a second predetermined amount, and
(iii) causes said image forming unit not to execute the operation in the toner supplying mode with an end of execution of formation of the images on the recording materials in the second number of sheets in the continuous image forming job in a case that the amount of the toner consumed by formation of the images formed on the recording materials in the first number of sheets in the continuous image forming job is the first predetermined amount and the continuous image forming job is not completed by the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job and that the amount of the toner consumed by formation of the images formed on the recording materials in the second number of sheets subsequent to the recording materials in the first number of sheets in the continuous image forming job is more than the second predetermined amount.

2. The image forming apparatus according to claim 1 , wherein said controller causes said image forming unit to execute the operation in the toner supplying mode so that
an amount of the toner supplied to said image bearing member when said controller causes said image forming unit to execute the operation in the toner supplying mode with the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job in a case that an amount of the toner consumed by formation of the images formed on the recording materials in the first number of sheets in the continuous image forming job is the first predetermined amount and that the continuous image forming job is completed by the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job, and
an amount of the toner supplied to said image bearing member when said controller causes said image forming unit to execute the operation in the toner supplying mode with the end of execution of formation of the images on the recording materials in the second number of sheets in the continuous image forming job in a case that the amount of the toner consumed by formation of the images formed on the recording materials in the first number of sheets in the continuous image forming job is the first predetermined amount and the continuous image forming job is not completed by the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job and that the amount of the toner consumed by formation of the images formed on the recording materials in the second number of sheets subsequent to the recording materials in the first number of sheets in the continuous image forming job is not more than the second predetermined amount
are equal to each other.

3. The image forming apparatus according to claim 1 , wherein said controller causes said image forming unit to execute the operation in the toner supplying mode so that
an amount of the toner supplied to said image bearing member when said controller causes said image forming unit to execute the operation in the toner supplying mode with the end of execution of formation of the images on the recording materials in the second number of sheets in the continuous image forming job in a case that the amount of the toner consumed by formation of the images formed on the recording materials in the first number of sheets in the continuous image forming job is the first predetermined amount and the continuous image forming job is not completed by the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job and that the amount of the toner consumed by formation of the images formed on the recording materials in the second number of sheets subsequent to the recording materials in the first number of sheets in the continuous image forming job is not more than the second predetermined amount,
is larger than
an amount of the toner supplied to said image bearing member when said controller causes said image forming unit to execute the operation in the toner supplying mode with the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job in a case that an amount of the toner consumed by formation of the images formed on the recording materials in the first number of sheets in the continuous image forming job is the first predetermined amount and that the continuous image forming job is completed by the end of execution of formation of the images on the recording materials in the first number of sheets in the continuous image forming job.

4. The image forming apparatus according to claim 1 , wherein said controller
causes said image forming unit to execute the operation in the toner supplying mode with an end of execution of formation of the images on the recording materials in the second number of sheets in the continuous image forming job in a case that the amount of the toner consumed by formation of the images formed on the recording materials in the first number of sheets in the continuous

Assignees

• Canon Kk

Inventors

• Saito Fumiyoshi
• Nose Katsuya
• Yago Toshihisa
• Mugita Naoki

Classifications

• G03G15/556 Primary

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

• G03G2215/0607

  two-component · CPC title

• G03G15/0844 Primary

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

• G03G15/09

  using magnetic brush · CPC title

• G03G15/0849

  Detection or control means for the developer concentration · CPC title