Image forming apparatus that performs compulsory toner consumption processing

Patent metadata

Field	Value
Publication number	US-9568877-B2
Application number	US-201615044070-A
Country	US
Kind code	B2
Filing date	Feb 15, 2016
Priority date	Feb 27, 2015
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

An image forming apparatus is provided. The image forming apparatus includes an image forming device to form images of color toners on corresponding image bearers of at least four image bearers; a transferring device to transfer the color toner images on the image bearers to a transfer medium; and a controller to control the image forming apparatus. The controller performs a compulsory toner consumption processing for the color toners to compulsory consume deteriorated toners. When the compulsory toner consumption processing is performed on three or more toners, compulsory consumption toner images of the color toners are formed on the corresponding image bearers and then transferred to the transfer medium to form a compulsory consumption combined toner image including at least two overlaid image portions, wherein the at least two overlaid image portions are arranged side by side with a space therebetween in a width direction of the transfer medium.

First claim

What is claimed is:

1. An image forming apparatus comprising:
an image forming device which includes at least four image bearers and which forms images of color toners on corresponding image bearers of the at least four image bearers;
a transferring device which includes a movable transfer medium and which transfers the color toner images on the at least four image bearers to the transfer medium; and
a controller to control the image forming apparatus,
wherein the controller performs a compulsory toner consumption processing including calculating a necessary toner compulsory consumption amount of each of the color toners to determine a necessary toner compulsory consumption cumulative amount thereof; specifying color toners whose necessary toner compulsory consumption cumulative amount is greater than a threshold value; forming compulsory consumption toner images of the specified color toners on the corresponding image bearers; and transferring the compulsory consumption toner images to the transfer medium to form a compulsory consumption combined toner image on the transfer medium, wherein when a number of the specified color toners is three or more, the compulsory consumption combined toner image includes at least two overlaid image portions each consisting of two of the compulsory consumption toner images, wherein the at least two overlaid image portions are arranged side by side with a space therebetween in a first direction perpendicular to a moving direction of the transfer medium.

2. The image forming apparatus according to claim 1 , wherein when the number of the specified color toners is three, the compulsory consumption combined toner image is an anomalous compulsory consumption toner image which includes first and second short compulsory consumption toner images of two of the specified color toners and a long compulsory consumption toner image of the other of the specified color toners, wherein the first and second short compulsory consumption toner images are arranged side by side with a space therebetween and the long compulsory consumption toner image is overlapped with each of the first and second short compulsory consumption toner images to form the at least two overlaid image portions.

3. The image forming apparatus according to claim 2 , wherein the toner of the long compulsory consumption toner image has a highest necessary toner compulsory consumption cumulative amount among the specified three color toners.

4. The image forming apparatus according to claim 1 , wherein when the number of the specified color toners is four, the compulsory consumption combined toner image is a first-direction parallel compulsory consumption toner image which includes, as the at least two overlaid image portions, first and second short compulsory consumption toner images which consist of two of the specified color toners and are overlaid, and third and fourth short compulsory consumption toner images which consist of the other two of the specified color toners and are overlaid.

5. The image forming apparatus according to claim 1 , wherein the controller performs the compulsory toner consumption processing in such a manner that positions of the at least two overlaid image portions are changed with each other at intervals.

6. The image forming apparatus according to claim 1 , wherein the controller performs the compulsory toner consumption processing in such a manner that positions of the at least two overlaid image portions are changed with each other in a next compulsory toner consumption processing.

7. The image forming apparatus according to claim 1 , wherein the transfer medium is an endless multi-layer transfer belt having an outermost layer made of an elastic material, and the image forming apparatus further comprises:
a nip forming member to form a transfer nip with the transfer belt by contacting the transfer belt;
a transfer power source to output a transfer bias of an AC and DC superimposition voltage to the nip forming member so that a transfer current flows at the transfer nip;
a sheet feeding device to feed a recording sheet to the transfer nip;
a first cleaner to clean a surface of the transfer belt after the transfer belt passes the transfer nip; and
a second cleaner to clean a surface of the nip forming member after the nip forming member passes the transfer nip,
wherein the color toner images on the transfer belt to be output as a print are transferred to the recording sheet at the transfer nip and toner remaining on the transfer belt without being transferred to the recording sheet is removed therefrom by the first cleaner, and
wherein the compulsory consumption combined toner image on the transfer belt is transferred to the nip forming member at the transfer nip and then removed from the nip forming member by the second cleaner.

8. The image forming apparatus according to claim 7 , wherein the controller performs control such that when a continuous printing operation of forming two or more toner images on two or more of the recording sheet is performed, the controller performs the compulsory toner consumption processing in parallel with the continuous printing operation, wherein the compulsory consumption combined toner image is transferred to an inter-sheet area of the transfer belt between two areas of the transfer belt contacting the two or more of the recording sheet.

Assignees

• Kamihara Kazuaki
• Higa Takuma
• Motohashi Toshiaki
• Ricoh Co Ltd

Inventors

• Kamihara Kazuaki
• Higa Takuma
• Motohashi Toshiaki

Classifications

• G03G15/0189

  primary transfer to an intermediate transfer belt (G03G15/0184 takes precedence) · CPC title

• G03G15/556 Primary

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

• G03G21/0041

  using a band; Details of cleaning bands, e.g. band winding · CPC title

• G03G15/0844

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