Image forming apparatus, and control system, cartridge and memory medium for the same apparatus

• US 20050047805A1
• Filed: 08/25/2004
• Published: 03/03/2005
• Est. Priority Date: 08/28/2003
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Okubo, Kazuhiro
• Granted Patent: US 7,149,437 B2
• Time in Patent Office: Days
• US Class Current: 399/27
• CPC Class Codes: G03G 15/0849 Detection or control means for the developer concentration
• CPC Class Codes: G03G 15/0863 provided with identifying means or means for storing process- or use parameters, e.g. an electronic memory
• CPC Class Codes: G03G 15/0877 Arrangements for metering and dispensing developer from a developer cartridge into the development unit
• CPC Class Codes: G03G 2221/1823 Cartridges having electronically readable memory

Abstract

The image forming apparatus onto which a cartridge having a developing apparatus and memory medium is detachably mountable, a detector for detecting toner concentration, and a control unit for selecting an operational mode from a first operational mode and second operational mode, wherein a toner supply member starts to supply a toner to the developing apparatus on the basis of a value detected by the detector in the first operational mode, and on the basis of a cumulative value of image signals for printing in the second operational mode, wherein the memory medium stores information based on which the second operational mode is switched to the first operational mode, and the control unit works to switch the second operational mode in operation to the first operational mode on the basis of information related to the cumulative value of image signals and information stored in the memory medium. This structure allows the image forming apparatus to keep toner concentration in the cartridge at an adequate level.

Claims

1. An image forming apparatus on which a cartridge having a developing apparatus and memory medium is detachably mountable, comprising:

a detector for detecting toner concentration, and

a control unit for selecting an operational mode from a first operational mode and second operational mode, wherein the first operational mode allows a toner supply member to start supplying a toner to the developing apparatus on the basis of a value detected by the detector, and the second operational mode allows the toner supply member to operate on the basis of a cumulative value of image signals for printing,

wherein the memory medium stores information based on which the second operational mode is switched to the first operational mode, and

the control unit works to switch the second operational mode in operation to the first operational mode on the basis of information related to the cumulative value of image signals and information stored in the memory medium.

2. An image forming apparatus according to claim 1, wherein the control unit switches the first operational mode to the second operational mode when difference between a value detected by the detector and given standard value attains a given threshold value.

3. An image forming apparatus according to claim 1, wherein the information stored in the memory medium is cumulative threshold information of the image signals.

4. An image forming apparatus according to claim 3, wherein the control unit switches the second operational mode to the first operational mode when information about the cumulative value of the image signals attains the cumulative threshold information of the image signal.

5. An image forming apparatus according to claim 2, wherein the memory medium further stores information related to the given standard value.

6. An image forming apparatus according to claim 5, wherein information related to the given standard value includes information of set level of initial toner concentration and information for correcting the set level of initial toner concentration in accordance with an atmosphere under which the image forming apparatus works and number of printed media.

7. A cartridge detachably mountable onto an image forming apparatus including a detector for detecting toner concentration in a developing apparatus and operating a toner supply member on the basis of a value detected by the detector in a first operational mode and on the basis of a cumulative value of image signals for printing in a second operational mode, wherein said cartridge comprising:

the developing apparatus; and

a memory medium having a memory region which stores information based on which the second operational mode is switched to the first operational mode.

8. A cartridge according to claim 7, wherein the memory medium further has a memory region which stores information related to a given standard value based on which the toner supply means is operated in the first operational mode.

9. A cartridge according to claim 8, wherein the information related to a given standard value includes information of set level of initial toner concentration and information for correcting the set level of initial toner concentration in accordance with an atmosphere under which the image forming apparatus works and number of printed media.

10. A cartridge according to claim 7, wherein the information based on which the second operational mode is switched to the first operational mode is a cumulative threshold value of the image signals.

11. A cartridge according to claim 7, further including the detector.

12. A memory medium to be set in a cartridge detachably mountable onto an image forming apparatus including a detector for detecting toner concentration in a developing apparatus and operating a toner supply member on the basis of a value detected by the detector in a first operational mode and on the basis of a cumulative value of image signals for printing in a second operational mode, wherein the cartridge is equipped with the developing apparatus, and

the memory medium has a memory region which stores information based on which the second operational mode is switched to the first operational mode.

13. A memory medium according to claim 12, further comprising a memory region which stores the information related to a given standard value based on which the toner supply means is operated in the first operational mode.

14. A memory medium according to claim 13, wherein the information related to a given standard value includes information of set level of initial toner concentration and information for correcting the set level of initial toner concentration in accordance with an atmosphere under which the image forming apparatus works and number of printed media.

15. A memory medium according to claim 12, wherein the information based on which the second operational mode is switched to the first operational mode is a cumulative threshold information of the image signals.

16. A control system for an image forming apparatus including a detector for detecting toner concentration in a developing apparatus and starting a toner supply member on the basis of a value detected by the detector in a first operational mode and on the basis of a cumulative value of image signals for printing in a second operational mode, wherein the image forming apparatus is composed of the apparatus body and a cartridge,

the cartridge is equipped with the developing apparatus and a memory medium having a memory region which stores information based on which the second operational mode is switched to the first operational mode,

the apparatus is equipped with a control unit which selects an operational mode from the first and second operational modes, and

the control unit switches the second operational mode to the first operational mode on the basis of the information on the cumulative value of image signals and information stored in the memory medium.

17. A control system according to claim 16, wherein the memory medium further has a memory region which stores information related to a given standard value based on which the first operational mode is switched to the second operational mode.

18. A control system according to claim 17, wherein the information related to a given standard value includes information of set level of initial toner concentration and information for correcting the set level of initial toner concentration in accordance with an atmosphere under which the image forming apparatus works and number of printed media.

19. A control system according to claim 16, wherein the information based on which the second operational mode is switched to the first operational mode is a cumulative threshold value information of the image signals.