Image Forming Apparatus and a Method of Controlling the Image Forming Apparatus

Abstract

An image forming apparatus, includes: a developer which is attachable to and detachable from an apparatus main body and which holds toner; an image forming section which forms a toner image using the toner held inside the developer; and a controller which executes a density control operation of forming a patch image using the toner held inside the developer and controlling an image forming condition for the image forming section based on a density detection result of the patch image, wherein the developer includes a memory which stores specific information regarding an attribute which is specific to the developer, and the controller determines a mode of the density control operation based on the specific information read out from the memory.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing which shows an embodiment of an image forming apparatus according to the invention.

FIG. 2 is a block diagram of an electric structure of the image forming apparatus shown in FIG. 1.

FIG. 3 is a flow chart which outlines the control operation in this apparatus.

FIG. 4 is a chart for describing the timing of executing the density control operation.

FIG. 5 is a flow chart of the density control operation.

FIG. 6 is a drawing which shows a first example of the target density value tables.

FIG. 7 is a drawing which shows a second example of the target density value tables.

FIG. 8 is a diagram which shows tone processing blocks of the image forming apparatus.

FIG. 9 is a flow chart of the tone control processing.

FIG. 10 is a drawing which shows one example of the OD value conversion tables.

FIG. 11 is a drawing which shows other example of the OD value conversion tables.

FIGS. 12A and 12B are drawings which show examples of patch images.

FIG. 13 is a drawing which shows one example of a method of determining the conversion processing characteristic by correcting the standard characteristic.

Claims

1. An image forming apparatus, comprising: a developer which is attachable to and detachable from an apparatus main body and which holds toner;an image forming section which forms a toner image using the toner held inside the developer; anda controller which executes a density control operation of forming a patch image using the toner held inside the developer and controlling an image forming condition for the image forming section based on a density detection result of the patch image, whereinthe developer includes a memory which stores specific information regarding an attribute which is specific to the developer, andthe controller determines a mode of the density control operation based on the specific information read out from the memory.

2. The image forming apparatus of claim 1, wherein the memory stores, as the specific information, timing information regarding the timing at which the density control operation using the developer should be executed, andthe controller executes the density control operation at the timing which is determined based on the timing information read out from the memory.

3. The image forming apparatus of claim 2, wherein the timing information contains a threshold value which is set in accordance with use history information indicative of a physical quantity which changes with use of the developer, andthe controller manages the use history information and executes the density control operation when the value of the use history information reaches the threshold value.

4. The image forming apparatus of claim 1, wherein the controller reads out the specific information stored in the memory upon power-on of the apparatus.

5. The image forming apparatus of claim 1, wherein the controller reads out the specific information stored in the memory when a developer is attached to the apparatus main body.

6. The image forming apparatus of claim 2, wherein at the time of execution of the density control operation, the controller reads out the timing information regarding the next density control operation from the memory.

7. The image forming apparatus of claim 1, wherein the memory stores as the specific information a specific-to-developer control parameter, from among control parameters which are required for the density control operation, which should be set in accordance with attributes of the developer and toner inside the developer, andthe controller executes the density control operation applying the specific-to-developer control parameter read out from the memory.

8. The image forming apparatus of claim 7, wherein the specific-to-developer control parameter includes a value which corresponds to a control target condition which is a target image forming condition in the density control operation, andthe controller executes the density control operation so that the image forming condition matches the control target condition.

9. The image forming apparatus of claim 7, wherein the specific-to-developer control parameter includes a value which is indicative of a proper range of the density of the patch image, andthe controller executes predetermined error processing when the density detection result of the patch image is not within the proper range.

10. The image forming apparatus of claim 1, wherein the memory stores, as the specific information, attribute information regarding the attribute of toner held inside the developer, and the image forming section includes an image carrier which carries a toner image, and a transferring/fixing section which finally transfers and fixes the toner image on a recording material, the apparatus further comprising: a density detector which detects a density of a toner image which is formed as the patch image by the image forming section on the image carrier; anda converter which performs conversion processing in which the density of the patch image on the image carrier detected by the density detector is converted into an image density on the recording material, whereinthe controller adjusts an operating condition for an image forming operation performed by the image forming section based on a conversion result obtained by the converter, to thereby control the image density on the recording material, anda conversion processing characteristic of the conversion processing performed by the converter is set based on the attribute information read out from the memory.

11. The image forming apparatus of claim 10, wherein a plurality of types of conversion processing characteristic different from each other are prepared in advance as the conversion processing characteristic of the conversion processing performed by the converter, andthe converter performs the conversion processing using one conversion processing characteristic which is selected based on the attribute information from among the plurality of types of conversion processing characteristic.

12. The image forming apparatus of claim 10, wherein a standard conversion processing characteristic is prepared in advance as the conversion processing characteristic of the conversion processing performed by the converter, andthe converter performs the conversion processing using a corrected conversion processing characteristic which is obtained by correcting the standard conversion processing characteristic based on the attribute information.

13. The image forming apparatus of claim 10, wherein the attribute information expresses the conversion processing characteristic which matches with toner held inside the developer, andthe converter performs the conversion processing using the conversion processing characteristic which is expressed by the attribute information.

14. The image forming apparatus of claim 10, wherein the converter performs the conversion processing based on a conversion table which is indicative of a correlation between an image density on the image carrier and an image density on the recording material.

15. The image forming apparatus of claim 10, wherein the memory further stores timing information which is indicative of a timing at which the conversion processing characteristic of the conversion processing performed by the converter should be changed in accordance with a change with time of the property of toner held inside the developer, andthe converter changes the conversion processing characteristic based on the timing information out read from the memory.

16. The image forming apparatus of claim 10, wherein the controller controls a tone correction characteristic of the apparatus based on a conversion result obtained by the converter.

17. A method of controlling an image forming apparatus, comprising: storing specific information regarding an attribute which is specific to a developer in a memory provided in the developer which is attachable to and detachable from an apparatus main body;reading out the specific information stored in the memory;determining, based on the specific information, a mode of a density control operation of forming a toner image using toner held inside the developer as a patch image, and of controlling an image forming condition for an image forming section based on a density detection result of the patch image; andexecuting the density control operation in thus determined mode.

18. The method of controlling an image forming apparatus of claim 17, wherein timing information is stored in the memory as the specific information, the timing information regarding a timing at which the density control operation using the developer to execute,the timing information is read out which is stored in the memory provided in the developer, andthe density control operation is executed at a timing determined based on the timing information.

19. The method of controlling an image forming apparatus of claim 17, wherein a specific-to-developer control parameter is stored in the memory as the specific information, the specific-to-developer control parameter corresponding to attributes of the developer and the toner inside the developer, andin executing the density control operation, the specific-to-developer control parameter read out from the memory is applied.

20. The method of controlling an image forming apparatus of claim 17, wherein attribute information is stored in the memory as the specific information, the attribute information regarding an attribute of toner held inside the developer, andin executing the density control operation: conversion processing is performed which is conversion of the density detection result of the patch image on the image carrier into an image density on the recording material,an operating condition for an image forming operation performed by the image forming section is adjusted based on the result of the conversion processing, to thereby control the image density on the recording material, andthe conversion processing characteristic for the conversion processing is set based on the attribute information read out from the memory.