# Patent

## Title
Cartridge, image forming apparatus and quality determining method of cartridge

## Abstract

A cartridge comprises a housing configured to hold a color erasable material which is erasable by heating to a color erasing temperature. The cartridge further comprises a temperature sensing unit configured to detect a temperature of the housing and a recording section configured to record the detected temperature of the housing.

## Background
FIELD
Embodiments described herein relate to a cartridge for managing the state of a developing agent or ink and the like in a copier or printer, an image forming apparatus and a quality determining method of a cartridge.
BACKGROUND
There is an apparatus for exchanging the cartridge in a multi-function peripheral (MFP) or printer for holding consumables such as toner or ink. An apparatus using the cartridge includes an apparatus for determining whether or not a new exchanged cartridge is an approved cartridge. However, if the color material of the toner or ink in a cartridge is a color erasable material which is erasable by heating, the color erasable material may be erased in a high-temperature environment even if the cartridge is unused. Therefore, if a color erasable material is housed in a cartridge, in addition to a determination on whether or not a cartridge is approved, a determination on the quality of the cartridge is also needed to be carried out.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of a Multi-Function Peripheral (MFP), according to a first embodiment;
FIG. 2 is a partial perspective view illustrating a toner cartridge, according to the first embodiment;
FIG. 3 is a diagram illustrating a temperature sensor unit, according to the first embodiment;
FIG. 4 is a block diagram illustrating a control system for determining the quality of the toner cartridge, according to the first embodiment;
FIG. 5 is a flowchart illustrating the quality determination for an unused toner cartridge, according to the first embodiment;
FIG. 6 is a partial perspective view illustrating a toner cartridge and an integrated circuit (IC) card, according to a second embodiment;
FIG. 7 is a diagram illustrating a RFID system, according to the second embodiment;
FIG. 8 is a block diagram illustrating a control system for determining the quality of the toner cartridge, according to the second embodiment.



DETAILED DESCRIPTION
A cartridge according to an embodiment comprises a housing configured to hold a color erasable material which is erasable by heating to a color erasing temperature. The cartridge further comprises a temperature sensing unit configured to detect a temperature of the housing and a recording section configured to record the detected temperature of the housing.
Embodiments are described below.
Embodiment 1
The image forming apparatus of an embodiment 1 is described below with reference to accompanying drawings FIG. 1-FIG. 5. An MFP (Multi-Function Peripheral) 10 serving as an image forming apparatus shown in FIG. 1 includes a printer section 11, a scanner section 12, a paper feed section 13 and a paper discharge section 22. The MFP 10 includes a CPU 120 serving as a control section for controlling the whole MFP 10.
The MFP 10 includes a control panel 50. The control panel 50 includes an operation panel 50a and a touch panel type display 50b. The operation panel 50a accepts an input of, for example, a user. The display 50b accepts the input of, for example, a user and/or displays information for the user.
The MFP 10 includes a card reader 52 serving as a medium reading section. The card reader 52 reads an integrated circuit (IC) card for resetting a timer or a counter which records the usage amount of a consumable such as a photoconductive drum 14 or a developer 18 when the consumable is exchanged. The MFP 10 is connected with a telephone line or a computer terminal via an interface 10a. 
The paper feed section 13 has a paper feed cassette 13a including a paper feed roller 15. A sheet P is stored in the paper feed cassette 13a. The sheet P stored in the paper feed cassette 13a may be either of an unused sheet or a reused sheet (i.e., a sheet erased through an image erasing process).
The MFP 10 includes a conveyance path 23 for conveying the sheet P from the paper feed section 13, through the printer section 11, and to the paper discharge section 22. The conveyance path 23 includes a conveyance roller 23a, a resist roller 23b and a paper discharge roller 23c. 
The printer section 11 is, for example, an electrophotographic type printer which forms an image with color erasable toner serving as a color erasable material in which the color is erased by heating. The printer section 11 includes a charger 16, an exposure scanning head 17, a developer 18 and a cleaner 21 around a photoconductive drum 14 rotating in the direction indicated by the arrow m. The charger 16 charges the photoconductive drum 14. The exposure scanning head 17 radiates exposure light towards the photoconductive drum 14 based on image data to form an electrostatic latent image on the photoconductive drum 14.
The developer 18 feeds toner for the electrostatic latent image on the photoconductive drum 14 with, for example, a two-component developing agent composed of a mixture of toner and a magnetic carrier. The toner refers to color erasable toner which can be erased at a color erasing temperature.
The color erasable toner includes a coloring agent, a color generation compound and a color developing agent in binder resin. If a fixed toner image formed with the color erasable toner is heated to the color erasing temperature, then the color generation compound and the color developing agent in the color erasable toner are dissociated to erase the toner image. For example, the color erasable toner can be fixed on a sheet at a relatively low temperature and erased at a temperature higher than the fixing temperature, for example at about 10 degrees centigrade higher.
A transfer device 20 transfers the toner image formed on the photoconductive drum 14 onto the sheet P. The charger 16, the exposure scanning head 17, the developer 18 and the transfer device 20 constitute an image forming section.
The printer section 11 includes a cartridge inserting section 36 of the MFP 10 above the developer 18. A toner cartridge 30 is installed in the cartridge inserting section 36 in an exchangeable manner. The toner cartridge 30 holds the color erasable toner and replenishes the color erasable toner to the developer 18. The printer section 11 has a fixer 24 which is arranged between the photoconductive drum 14 and the paper discharge section 22 along the conveyance path 23. The fixer 24 heats the toner image formed on the sheet P to a fixing temperature (lower than the color erasing temperature) to fix the toner image on the sheet P without erasing the toner image.
With the configuration above, the MFP 10 forms, by using the printer section 11, a printed image on the sheet P fed from the paper feed section 13 with the color erasable toner, and discharges the sheet P to the paper discharge section 22.
The fixer 24 may also be used as a heater for erasing the printed image formed on the sheet P with the color erasable toner. Accordingly, the MFP 10 may also function as a color erasing apparatus.
The image forming apparatus, which is not limited to the MFP 10, may further be a monochromatic image forming apparatus, and no limitation is given to the number of the developing apparatus. The image forming apparatus may transfer a toner image onto a sheet directly from a photoconductive member. Besides, the image forming apparatus may comprise a plurality of printer sections. The image forming apparatus may further be an inkjet type image forming apparatus using a color erasable ink, that is, color erasable material which is erasable by heating.
If the toner cartridge 30 runs out of toner during the printing period of the printer section 11, the MFP 10 displays information ‘exchange toner cartridge’ on the display 50b. If the information ‘exchange toner cartridge’ is displayed on the display 50b, the user exchanges the used toner cartridge 30a for an unused toner cartridge 30b. 
As shown in FIG. 2 and FIG. 3, the toner cartridge 30 holding a color erasable toner includes a housing 31, a toner supplying section 34a, a supplying section driving gear 34b, a connector 35 and a temperature sensor unit 26. The connector 35 is an interface which is electrically connected with the MFP 10 when the toner cartridge 30 is incorporated into the cartridge inserting section 36 of the MFP 10. The temperature sensor unit 26 includes a temperature memory 32 serving as a recording section, a temperature sensor 33 serving as a temperature detection section, a converter 27, a controller 28 and a power supply 29.
The temperature sensor 33 detects the temperature of the toner cartridge 30 during a storage period from the time that the toner cartridge 30 is manufactured to the time that the toner cartridge 30 is delivered to the user. The converter 27 converts the electric signal from the temperature sensor 33 and sends the converted signal to the controller 28. The controller 28 writes the temperature detected by the temperature sensor 33 into the temperature memory 32. Additionally, the controller 28 is electrically connected with the connector 35. That is, in a condition that the toner cartridge 30 is incorporated into the cartridge inserting section 36 of the MFP 10, the temperature data held by the temperature memory 32 is transferred to the MFP 10 via the connector 35. The temperature memory 32 includes, for example, a nonvolatile memory such as an EEPROM, a Flash ROM or a flash memory. The temperature memory 32 records the detection result of the temperature sensor 33 as a temperature record (temperature data) of the toner cartridge 30. The temperature data recorded in the temperature memory 32 is referred hereinafter to as management temperature. If the management temperature recorded in the temperature memory 32 is higher than color erasing temperature of a toner, the color erasable toner in the toner cartridge 30 is thermally erased.
The temperature memory 32 is capable of rewriting the management temperature successively so as to only store the maximum temperature detected by the temperature sensor 33.
The power supply 29 supplies power to the controller 28 so that the controller 28 can write temperature data into the temperature memory 32.
The MFP 10 includes a cartridge reading section 37, serving as a record reading section, in the cartridge inserting section 36. The cartridge reading section 37 reads the management temperature recorded in the temperature memory 32 of the unused toner cartridge 30b when the toner cartridge 30 is exchanged.
When the toner cartridge 30 is exchanged, the CPU 120 determines the quality of the unused toner cartridge 30b. A control system 60 for determining the quality of the unused toner cartridge 30b is described with reference to the block diagram shown in FIG. 4. The control system 60 includes a reading control circuit 70, a cartridge determination circuit 71 and an operation panel control circuit 72. The control system 60 is controlled by the CPU 120 (which controls the whole MFP 10).
The CPU 120 executes instructions stored in the storage section 61 to perform a printing function using the color erasable toner. The storage section 61 includes a ROM (Read Only Memory) 61a and a RAM (Random Access Memory) 61b. A control method and control data for of basic actions of an image forming processing are stored in the ROM 61a. The toner color erasing temperature of the color erasable toner used by, for example, the developer 18, is stored in the ROM 61a. The RAM 61b is a working memory for temporarily storing the maximum temperature read by the cartridge reading section 37.
The reading control circuit 70 controls the cartridge reading section 37 to read the temperature memory 32. The cartridge determination circuit 71 determines the quality of the unused toner cartridge 30b according to the management temperature recorded in the temperature memory 32 read by the cartridge reading section 37. The operation panel control circuit 72 controls the operation panel 50a and the display 50b. 
The quality determination process conducted for the unused toner cartridge 30b installed in the MFP 10 when the toner cartridge 30 is exchanged is now described with reference to the flowchart shown in FIG. 5. If the user exchanges the toner cartridge 30, the CPU 120 starts to determine the quality of the unused toner cartridge 30b. 
The cartridge reading section 37 reads the temperature memory 32 under the control of the reading control circuit 70 (ACT 100). The cartridge determination circuit 71 compares the highest management temperature read by the cartridge reading section 37 from the temperature memory 32 with the toner color erasing temperature stored in the ROM 61a (ACT 101).
If the highest management temperature is higher than the toner color erasing temperature (Yes in ACT 101), then the cartridge determination circuit 71 determines that the exchanged unused toner cartridge 30b is a defective product. Then, the CPU 120 proceeds to ACT 102. In ACT 102, the operation panel control circuit 72 displays the determination result of the cartridge determination circuit 71 on the display 50b of the control panel 50.
In ACT 102, the display 50b displays information such as “the installed unused toner cartridge is a defective product” and “please exchange the toner cartridge again.” The CPU 120 prompts the user to exchange the installed unused toner cartridge for a new one and ends the quality determination process for of the installed unused toner cartridge 30b. 
If the highest management temperature is below the toner color erasing temperature (No in ACT 101), then the cartridge determination circuit 71 determines that the exchanged unused toner cartridge 30b is a satisfactory product. The CPU 120 proceeds to ACT 103. In ACT 103, the operation panel control circuit 72 displays the determination result of the cartridge determination circuit 71 on the display 50b of the control panel 50.
In ACT 103, the display 50b displays, for example, “the exchange of the toner cartridge is finished.” The CPU 120 ends the quality determination process conducted for the installed unused toner cartridge 30b. If the exchanged unused toner cartridge 30b is a satisfactory product, then the MFP 10 replenishes color erasable toner from the toner cartridge 30.
The CPU 120 determines the quality of the unused toner cartridge 30b every time the user exchanges the toner cartridge 30. The determination result of the cartridge determination circuit 71 may further be displayed on a display of the computer terminal connected with the MFP 10.
According to the first embodiment, the management temperature detected by the temperature sensor 33 during the period from when the toner cartridge 30 is manufactured to the moment when the toner cartridge 30 is delivered to the user is recorded in the temperature memory 32. The temperature memory 32 is read when the toner cartridge 30 is exchanged, and the quality of the unused toner cartridge 30b is determined according to the maximum temperature recorded in the temperature sensor 32. If the maximum temperature recorded in the temperature memory 32 reaches the toner color erasing temperature, then it is determined that the color erasable toner in the housing 31 is erased, and that the unused toner cartridge 30b is a defective product. The user is notified of the result of the determination of the quality of the unused toner cartridge 30b. 
The exchange of the cartridge is carried out in a low-temperature environment so as to prevent a defective unused toner cartridge 30b having color erasable toner from being installed in the MFP 10. The replenishment of an erased toner from a defective unused toner cartridge 30b to the developer 18 is prevented. Thus deterioration of the developer 18 is prevented, and a high-quality printed image can be obtained.
Embodiment 2
The image forming apparatus of the second embodiment is described below with reference to accompanying drawings FIG. 6-FIG. 8. The difference of the second embodiment compared to the first embodiment is with respect to the structure of the recording medium for recording the management temperature of the cartridge. The configuration of the second embodiment that is the same as that described in the first embodiment is denoted by the same reference symbol and the description thereof is not repeated.
A color erasable toner is held in a toner cartridge 80 installed in the cartridge inserting section 36 in an exchangeable manner. As shown in FIG. 6, the toner cartridge 80 includes a housing 81, a toner supplying section 82a, a supplying section driving gear 82b, a connector 85, a temperature sensor unit 87 and an IC reader-writer 88. The connector 85 is an interface that electrically connects with the MFP 10. In the second embodiment, records are made in an IC card 86 through the RFID (Radio Frequency Identification) system 130 shown in FIG. 7 in an electromagnetic signal or electromagnetic induction.
The temperature sensor unit 87 includes a temperature sensor 87a serving as a temperature detection section, a converter 87b, a controller 87c and a power supply 87d. The temperature sensor 87a detects the temperature of the toner cartridge 80 during a storage period from the time that the toner cartridge 80 is manufactured to the time that the toner cartridge 80 is delivered to the user. The converter 87b converts the electric signal from the temperature sensor 87a and sends the converted signal to the controller 87c. The controller 87c sends the temperature detected by the temperature sensor 87a to the IC reader-writer 88. The controller 87c is electrically connected with the connector 85. The power supply 87d supplies power for the controller 87c. 
The IC reader-writer 88 records the electric signal sent from the temperature sensor unit 87 in the IC card 86 in a wireless communication manner. The IC reader-writer 88 includes a receiving section 88a for receiving the electric signal from the temperature sensor 87a, a controller 88b, a sending section 88c, an antenna 88d and a battery 88e. The controller 88b converts the electric signal received by the receiving section 88a from the temperature sensor 87a into a wireless signal through the sending section 88c and sends the converted wireless signal from the antenna 88d, as an electromagnetic wave signal, for example. The battery 88e supplies power for the controller 88b. 
At time of shipment of the toner cartridge 80, the IC card 86, serving as a recording medium including an IC chip 86a, is packed in a package 84 as an accessory. The IC chip 86a includes an antenna 86b, a receiving section 86c, a controller 86d and a nonvolatile IC memory 86e. The IC chip 86a receives, using the receiving section 8, the wireless signal sent from the IC reader-writer 88 through the antenna 86b. The controller 86d converts the wireless signal received by the receiving section 88a into an electric signal serving as the detection result of the temperature sensor 87a and writes the electric signal into the IC memory 86e. The IC memory 86e records the detection result of the temperature sensor 87a as the management temperature of the toner cartridge 80.
When exchanging a cartridge, the user installs an unused toner cartridge 80 into the cartridge inserting section 36. The IC card 86 is read with the card reader 52. The CPU 120 controlling the whole MFP 10 determines the quality of the unused toner cartridge 80 according to the management temperature recorded in the IC card 86 read by the card reader 52.
A control system 90 for determining the quality of the unused toner cartridge 80 is described with reference to the block diagram shown in FIG. 8.
The control system 90 includes a CPU 120 for controlling the whole MFP 10. The control system 90 includes a card reader control circuit 91, a cartridge determination circuit 71 and an operation panel control circuit 72 controlled by the CPU 120. The card reader control circuit 91 controls the card reader 52.
If the user exchanges the toner cartridge 80 and the IC card 86 is read with the card reader 52, the CPU 120 starts to determine the quality of the unused toner cartridge 80. If the highest management temperature read by the card reader 52 is higher than the toner color erasing temperature, then the CPU 120 determines that the exchanged unused toner cartridge 80 is a defective product. If the unused toner cartridge 80 is a defective product, then the CPU 120 displays the information for exchanging a new unused toner cartridge 80 on the display 50b. 
If the highest management temperature read by the card reader 52 is below the toner color erasing temperature, then the CPU 120 determines that the exchanged unused toner cartridge 80 is a satisfactory product. If the unused toner cartridge 80 is a satisfactory product, then the CPU 120 displays the information that the exchange of the toner cartridge is finished on the display 50b. 
In accordance with the second embodiment, the management temperature of the toner cartridge 80 detected by the temperature sensor 87a is recorded in the IC card 86. The IC card 86 is read when the toner cartridge 80 is exchanged, and the quality of an unused toner cartridge 80 is determined based on the maximum temperature recorded in the IC card 86. If the maximum temperature recorded in the IC card 86 reaches the toner color erasing temperature, then it is determined that the held color erasable toner is erased, and that the unused toner cartridge 80 is a defective product. The user is notified of the result of the quality determination of the unused toner cartridge 80.
The exchange of the cartridge is carried out in a low-temperature environment to prevent a defective unused toner cartridge 80 with color erasable toner from being installed in the MFP 10. The replenishment of an erased toner from a defective unused toner cartridge 80 to the developer 18 is prevented. Thus deterioration of the developer 18 is prevented, and a high-quality printed image can be obtained.
According to at least one embodiment described above, the use of an improper color erasable toner which is erased if the cartridge is placed in a high-temperature environment in the image forming is prevented. Therefore, a high-quality printed image can be obtained, without mixing the erased color erasable toner on the formed image.
In at least one embodiment described above, the cartridge, which is not limited to a toner cartridge, may be an exchangeable developing cartridge in which a color erasable material is held or a developing cartridge in which a toner bottle is integrated with a developer. In the case of an inkjet type image forming apparatus, the cartridge may further be an ink cartridge for holding ink serving as a color erasable material. Moreover, the cartridge may further be a cartridge tape with the color erasable ink on the tape.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the invention. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the invention.

## Claims

1. A cartridge, comprising:
a housing configured to hold a color erasable material which is erasable by heating to a color erasing temperature;
a temperature sensing unit configured to detect a temperature of the housing; and
a recording section configured to:
record the temperature detected by the temperature sensing unit if there is no previously recorded temperature,
record the detected temperature over a previously recorded temperature if the detected temperature is greater than the previously recorded temperature, and
not record the temperature detected by the temperature sensing unit if the detected temperature is less than a previously recorded temperature.

2. The cartridge according to claim 1, further comprising:
a connector configured to electrically connect with an image forming apparatus.

3. The cartridge according to claim 2, wherein:
the connector is configured to transmit the recorded temperature to the image forming apparatus after the connector is electrically connected to the image forming apparatus.

4. The cartridge according to claim 1, further comprising:
an integrated circuit reader-writer configured to receive the detected temperature and to transmit the received detected temperature to the recording section which is included on an integrated circuit card.

5. The cartridge according to claim 4, wherein:
the integrated circuit card is separate from the housing, and
the integrated circuit reader-writer is configured to transmit the received detected temperature to the recording section on the integrated circuit card as a wireless signal.

6. The cartridge according to claim 5, wherein:
the recording section on the integrated circuit card is configured to be read by a card reader on an image forming apparatus.

7. A cartridge temperature recording method comprising:
detecting a temperature of a cartridge holding a color erasable material which is erasable by heating to a color erasing temperature;
controlling a temperature memory on the cartridge so that:
the temperature detected by the temperature sensing unit is recorded in the temperature memory if there is no previously recorded temperature,
the detected temperature is recorded in the temperature memory over a previously recorded temperature if the detected temperature is greater than the previously recorded temperature, and
the detected temperature is not recorded in the temperature memory if the detected temperature is less than a previously recorded temperature; and

sending the recorded temperature to an image forming apparatus configured to determine the quality of the cartridge based on the detected temperature.

8. The method according to claim 7, further comprising:
determining the quality of the cartridge by comparing the sent temperature to the color erasing temperature.

9. The method according to claim 8, wherein:
the cartridge is determined to be satisfactory if the sent temperature is less than the color erasing temperature.

10. The method according to claim 7, further comprising:
mounting the cartridge in the image forming apparatus, wherein the recorded temperature is sent to the image forming apparatus after the cartridge is mounted in the image forming apparatus.

11. The method according to claim 7, wherein:
controlling the temperature memory includes receiving the detected temperature as a wireless signal on an integrated circuit card that includes the temperature memory.

12. The method according to claim 11, wherein:
sending the detected temperature to the image forming apparatus includes causing the integrated circuit card to be read by an integrated circuit card reader on the image forming apparatus.