Image forming apparatus and genuine product determining method for toner cartridge

This application is based upon and claims the benefit of priority from: U.S. provisional application 61/310,983, filed on Mar. 5, 2010, the entire contents of each of which are incorporated herein by reference.

Embodiments described herein relate generally to an image forming apparatus and the like.

Conventionally, a toner cartridge loaded in an image forming apparatus such as electrographic apparatus has an IC chip. In the IC chip, necessary data for control to prevent reduction in performance of the image forming apparatus and information for managing the toner cartridge are stored.

This information is performance information proper to disposables such as toner cartridge. It is extremely difficult for manufacturers of non-genuine products to produce the correct information. Consequently, in some cases, an IC chip as a genuine product is directly duplicated or altered and attached to other disposables such as toner cartridge and then distributed in the market with incorrect information written in the product. Users suffer disadvantages such as deterioration in image quality by continuing the use of non-genuine products by mistake. Moreover, there is a risk that the encroachment by the non-genuine products may impair the benefit to the genuine product manufacturer.

FIG. 1 is a longitudinal sectional view of an image forming apparatus.

FIG. 2 is a perspective view of a loading unit which a toner cartridge is loaded on and unloaded from, and the toner cartridge.

FIG. 3 is a functional block diagram of the image forming apparatus.

FIG. 4 is a schematic view schematically showing authentication codes.

FIG. 5 is a flowchart showing a procedure for determining whether a product is a genuine product or not.

FIG. 6 is a functional block diagram of an image forming apparatus according to a second embodiment.

FIG. 7 is a flowchart showing a procedure for changing an allowable time zone.

FIG. 8 is a functional block diagram of an image forming apparatus according to a third embodiment.

FIG. 9 is a flowchart showing a procedure for determining whether a product is a genuine product or not (third embodiment).

Hereinafter, embodiments will be described with reference to the drawings.

According to an embodiment, an image forming apparatus includes: a loading unit on which a toner cartridge is loaded, the toner cartridge having a first storage unit in which first information indicating at least a date of manufacture of toner is stored; an image forming unit which forms an image on a sheet; a counting unit which counts time; and a determination unit which determines whether the toner cartridge is a genuine product or not, based on how large a difference is between the first information and second information specified on the basis of a count result from the counting unit.

First Embodiment

FIG. 1 is a longitudinal sectional view of an image forming apparatus. However, some functional blocks are indicated by dotted lines. FIG. 2 is a perspective view of a loading unit which a toner cartridge is loaded on and unloaded from, and the toner cartridge. The arrows indicate the correspondence at the time of loading. FIG. 3 is a block diagram of the image forming apparatus.

An image forming apparatus 1 has an image reading unit R and an image forming unit P. The image reading unit R scans and reads an image of a sheet document. The image forming unit P forms a developer image on a sheet based on image data of the image read by the image reading unit R. The image reading unit R has an automatic document feeder 69 which automatically carries a document to a predetermined image reading position. A scanning optical system 70 reads an image of a document placed on a document tray Rt.

The image forming unit P has pickup rollers 51 to 54 , toner cartridges 10 Y to 10 K, photoconductive drums 20 Y to 20 K, developing devices 50 Y to 50 K, and a display unit 90 .

The image forming apparatus 1 has an apparatus storage unit 17 as a second storage unit, a timer 18 as a counting unit, and a control unit 19 . In the apparatus storage unit 17 , various programs which are executed in the image forming apparatus 1 are stored. The apparatus storage unit 17 may be a RAM (random access memory), ROM (read only memory), DRAM (dynamic random access memory), or SRAM (static random access memory). The control unit 19 controls various operations carried out in the image forming apparatus 1 . The control unit 19 may be an MPU or CPU and may include any number of MPUs and CPUs. The control unit 19 may also be an ASIC circuit which executes, in a circuit-based manner, at least a part of processing realized by the MPU and CPU. The timer 18 counts the current time. The timer 18 may also be installed inside the control unit 19 .

The pickup rollers 51 to 54 supply a sheet picked up from a cassette, to a sheet carrying path. A laser unit 40 forms an electrostatic latent image on each of the photoconductive drums 20 Y to 20 K based on image data of an image read from a document by the image reading unit R. In the toner cartridges 10 Y to 10 K, developers corresponding to yellow (Y), magenta (M), cyan (C) and black (K) are housed. The developing devices 50 Y to 50 K supply the developers to the photoconductive drums 20 Y to 20 K on which the electrostatic latent images are located. The developer images located on the photoconductive drums 20 Y to 20 K are transferred to a belt surface of an intermediate transfer belt. The developer images on the intermediate transfer belt 21 are transferred onto the carried sheet at a secondary transfer position T. The developer images transferred to the sheet are fixed by being heated by a fixing unit 67 . The sheet to which the developer images are fixed is discharged from a discharge tray 68 .

The toner cartridge 10 Y is detachably loaded on a loading unit 1 Ya in the image forming apparatus 1 . In FIG. 1 , the loading unit 1 Ya is indicated by dotted lines. A carrying screw 11 Y slices the toner housed in the toner cartridge 10 Y and carries the toner to the developing device 50 Y. The carrying screw 11 Y is driven by a screw motor, not shown. The driving force from the screw motor is transmitted to the carrying screw 11 Y via a main-body-side transmission gear 17 Y and a cartridge-side transmission gear 16 Y. The control unit 19 controls the driving of the screw motor.

The toner cartridges 10 M to 10 K are respectively loaded on the loading units 1 Ma to 1 Ka in the image forming apparatus 1 . In FIG. 1 , the loading units 1 Ma to 1 Ka are indicated by dotted lines. The configuration of the toner cartridges 10 M to 10 K is similar to the configuration of the toner cartridge 10 Y and therefore will not be described further in detail. The configuration of the loading units 1 Ma to 1 Ka is similar to the configuration of the loading unit 1 Ya and therefore will not be described further in detail.

The toner cartridge 10 Y has a cylindrical part 101 Y at the center in the direction of diameter. The cylindrical part 101 Y is located at one end in the longitudinal direction of the toner cartridge 10 Y. The cylindrical part 101 Y has cut-outs 102 Y at predetermined intervals at plural positions in the circumferential direction. A number of rotations detecting unit 13 Y is located in an area on the inner side of the cylindrical part 101 Y in the direction of diameter and is fixed to the loading unit 1 Ya. The number of rotations detecting unit 13 Y may be a photo-interrupter. The number of rotations detecting unit 13 Y has a light emitting element and a light receiving element. The number of rotations detecting unit 13 Y detects a light receiving state where light emitted from the light emitting element and passed through the cut-out 102 Y of the cylindrical part 101 Y is received by the light receiving element, and a non-light receiving state where light emitted from the light emitting element is interrupted by the wall part of the cylindrical part 101 Y and light reception by the light receiving element is prohibited. Thus, the number of rotations detecting unit 13 Y detects the number of rotations of the screw motor. The control unit 19 is electrically connected with the number of rotations detecting unit 13 Y and stores the number of rotations detected by the number of rotations detecting unit 13 Y into an IC chip 14 Y of the toner cartridge 10 Y.

The toner cartridge 10 Y has a chip fixing part 10 Ya at one end face in the longitudinal direction. The IC chip 14 Y is fixed to the chip fixing part 10 Ya and thus integrated with the toner cartridge 10 Y. The IC chip 14 Y may be a RAM (random access memory). History information of toner is stored in the IC chip 14 Y. The history information may include a manufacturing plant code, manufacturing lot code and classification code as well as the date of manufacture of the toner cartridge 10 Y. The IC chip 14 Y is attached to the chip fixing part 10 Ya when the toner cartridge 10 Y is manufactured. The loading unit 1 Ya has a chip terminal part 4 Y. The chip terminal part 4 Y has plural springs 4 Ya. In the state where the toner cartridge 10 Y is loaded on the loading unit 1 Ya, the these springs 4 Ya are pressurized and contact terminal pads 101 Ya of the chip fixing part 10 Ya. The IC chip 14 Y is located in an area which avoids the terminal pads 101 Ya of the chip fixing part 10 Ya.

When the screw motor stops rotating, the control unit 19 updates the number of rotations stored in the IC chip 14 Y. That is, the total number of rotations of the screw motor after the toner cartridge lay is loaded in the image forming apparatus 1 is stored in the IC chip 14 Y. Therefore, when the screw motor does not rotate, the control unit 19 does not update the total number of rotations stored in the IC chip 14 Y.

The developing device 50 Y is a magnetic brush-type and has a developing container 501 Y, a developing roller 502 Y, a mixer 503 Y, and a toner concentration sensor 504 Y as a second sensor. The developing devices 50 M to 50 K have a similar configuration to the configuration of the developing device 50 Y and therefore will not be described further in detail. The mixer 503 Y stirs the developer. The developer is made of toner and carrier for yellow. The toner may contain resin and carbon. The carrier includes ferrite and a coating layer formed on the surface of the ferrite. Since there is the coating layer on the surface of the ferrite, the triboelectric effect of the carrier and the toner becomes stable.

As the mixer 503 Y stirs the developer, a frictional force is generated between the toner and the carrier. The carrier is positively charged and the toner is negatively charged. The developing roller 502 Y has a magnet and its magnetic force attracts the developer, thereby forming a magnetic brush. As this magnetic brush contacts the photoconductive drum 20 Y rotating in the direction of arrow S, the electrostatic latent image on the photoconductive drum 20 Y becomes developed.

The toner concentration sensor 504 Y detects the toner concentration based on the magnetic permeability of the developer in the developing device 50 Y. That is, when the carrier ratio in the developer in the developing device 50 Y is increased, the magnetic permeability becomes higher and the toner concentration sensor 504 Y has a higher output value.

Next, the function of each unit in the image forming apparatus according to this embodiment will be described with reference to FIG. 3 . FIG. 3 is a functional block diagram of the image forming apparatus and the toner cartridge. The following description is about the toner cartridge 10 Y and the description of the other toner cartridges 10 M to 10 K is omitted.

The image forming apparatus 1 has a determination unit 30 , a loading unit 1 Ya, 1 Ma, 1 Ca, 1 Ka, an image forming unit P, the timer 18 , and the apparatus storage unit 33 . The toner cartridge 10 Y is loaded on the loading unit 1 Ya.

The timer 18 counts the current time. In the apparatus storage unit 17 , plural pieces of authentication information corresponding to each time counted by the timer 18 are stored.

FIG. 4 is an authentication code table showing an example of authentication information stored in the apparatus storage unit 17 . With reference to FIG. 4 , the authentication information stored in the apparatus storage unit 17 may be the year (Christian year) in which the toner cartridge 10 Y is manufactured. There are plural pieces of authentication information, including not only the year when the image forming apparatus 1 is shipped, but also plural years preceding and following that year. For example, the authentication information of a toner cartridge manufactured in the year 2008 is “2008”, and the authentication information of a toner cartridge 10 Y manufactured in the year 2011 is “2011”. This authentication information may be encrypted information such that its character information can be analyzed under predetermined rules so as to specify the year. The authentication information may also be the month of manufacture or the day of manufacture of the toner cartridge 10 Y.

The determination unit 30 acquires all the authentication information that corresponds to an allowable time zone (first authentication information), from the plural pieces of authentication information stored in the apparatus storage unit 17 , and determines that the toner cartridge 10 Y is a genuine product when one of these pieces of authentication information is identical with first information stored in the toner cartridge 10 Y. The first information will be described later.

The allowable time zone may be a period between a determination time when the determination unit 30 determines whether the toner cartridge 10 Y is a genuine product or not (hereinafter referred to as “determination time”) and an allowable start time before that determination time. The determination time may be a power-on time when power is turned on in the image forming apparatus 1 . The determination time may also be a loading time when the toner cartridge 10 Y is loaded in the loading unit 1 Ya.

As the period of the allowable time zone becomes longer, the accuracy of discriminating a non-genuine product becomes lower. As the period becomes shorter, the risk of erroneously regarding a genuine product as a non-genuine product increases. Therefore, it is desirable that the allowable start time is at least in or before the previous year of the year to which the determination time belongs.

The toner cartridge 10 Y has a first storage unit 81 . The first information indicating the date of manufacture of the toner cartridge 10 Y is stored in the first storage unit 81 . The first information corresponds to the authentication information stored in the second storage unit 33 . That is, if the date of manufacture is the year 2008, the same information as the authentication information stored in the apparatus storage unit 17 , that is, “2008” is stored as the first information.

The determination unit 30 compares the plural pieces of authentication information stored in the apparatus storage unit 17 with the first information stored in the first storage unit 81 . When there is identical information, the determination unit 30 regards the year corresponding to the identical authentication information as the year of manufacture. Moreover, the determination unit 30 determines whether the year of manufacture belongs to the allowable time zone or not, and thus determines whether the toner cartridge 10 Y is a genuine product or not.

Next, the method of determining whether the toner cartridge 10 Y is a genuine product or not, will be described more specifically with reference to the flowchart of FIG. 5 . In ACT 101 , the control unit 19 determines whether the toner cartridge 10 Y is loaded on the loading unit 1 Ya or not. When the toner cartridge 10 Y is loaded on the loading unit 1 Ya, the control unit 19 goes to ACT 102 .

In ACT 102 , the control unit 19 specifies the current time based on the count result from the timer 18 and goes to ACT 103 . In ACT 103 , the control unit 19 acquires all the authentication information belonging to the allowable time zone from the apparatus storage unit 17 and goes to ACT 104 .

In ACT 104 , the control unit 19 acquires the first information stored in the IC chip 14 Y and goes to ACT 105 . In ACT 105 , the control unit 19 compares the authentication information belonging to the allowable time zone with the first information. When these pieces of information are identical, the control unit 19 returns to ACT 101 . When these pieces of information are not identical, the control unit 19 goes to ACT 106 .

In ACT 106 , the control unit 19 displays alert information on the display unit 90 . The alert information may be character information showing that the toner is not a genuine product.

Second Embodiment

An image forming apparatus according to this embodiment will be described with reference to FIG. 1 , FIG. 6 and FIG. 7 . FIG. 6 is a functional block diagram of the image forming apparatus according to this embodiment. FIG. 7 is a flowchart of a correcting method to correct the length of the allowable time zone.

As the period of the allowable time zone becomes longer, the accuracy of discriminating a non-genuine product becomes lower. As the period becomes shorter, the risk of erroneously regarding a genuine product as a non-genuine product increases. Depending on the user, the toner consumption speeds of the toner cartridges 10 Y to 10 K varies. For example, if the user intensively uses monochrome print, the consumption speed of black (K) becomes relatively faster. Thus, in this embodiment, the consumption speeds of the toner cartridges 10 Y to 10 K are monitored and the length of the allowable time zone is changed according to the result of the monitoring.

The following description is about the toner cartridge 10 Y and the description of the other toner cartridges 10 M to 10 K is duplicate and therefore omitted. With reference to FIG. 6 , a first acquisition unit 34 acquires speed information about the consumption speed of each amount of toner discharged from the toner cartridge 10 Y.

The first acquisition unit 34 may be realized by the number of rotations detecting unit 13 Y and the control unit 19 in cooperation with each other. In the IC chip 14 Y, the result of detection by the number of rotations detecting unit 13 Y and the date and time of loading of the toner cartridge 10 Y are stored.

Therefore, the control unit 19 divides the total amount of supplied toner discharged from the toner cartridge 10 Y by the elapsed time from the date and time of loading, and thus calculates the consumption speed.

With reference to FIG. 7 , in ACT 201 , the control unit 19 determines whether the toner cartridge 10 Y is loaded on the loading unit 1 Ya or not. When the toner cartridge 10 Y is loaded on the loading unit 1 Ya, the control unit 19 goes to ACT 202 .

In ACT 202 , the control unit 19 specifies the current time based on the count result from the timer 18 and stores the current time as the date and time of loading in the IC chip 14 Y of the toner cartridge 10 Y.

In ACT 203 , the control unit 19 determines whether an inspection period is reached or not. Here, as the inspection period, a shorter time period than the typical consumption time of the toner charged in the toner cartridge 10 Y may be set. That is, since the inspection period is a period provided for calculating the consumption speed of the toner, the inspection period is set to have a length from which consumption trend can be grasped.

In ACT 204 , the control unit 19 reads out the result of detection by the number of rotations detecting unit 13 Y from the IC chip 14 Y and calculates the total amount of toner supplied. In ACT 205 , the control unit 19 calculates the elapsed time from the date and time of loading and calculates the consumption speed based on the elapsed time and the total amount of toner supplied.

In ACT 206 , the control unit 19 compares the consumption speed with a reference consumption speed. When the consumption speed is relatively slower, the control unit 19 goes to ACT 207 . When the consumption speed is relatively faster, the control unit 19 returns to ACT 203 . Here, the reference consumption speed may be defined as a designed value by the manufacturer based on the record of actual use, or may be inputted by the user operating the display unit 90 .

In ACT 207 , the control unit 19 extends the allowable time zone and updates the information stored in the apparatus storage unit 17 . Thus, the toner cartridge 10 Y, which is a genuine product, is prevented from being erroneously determined as a non-genuine product during the use of the toner cartridge 10 Y. Moreover, an appropriate allowable time zone according to the consumption speed of each toner is provided.

Third Embodiment

An image forming apparatus according to this embodiment will be described with reference to FIG. 1 , FIG. 8 and FIG. 9 . FIG. 8 is a functional block diagram of the image forming apparatus according to this embodiment. FIG. 9 is a flowchart of a determination method to determine whether the product is a genuine product or not.

When the life of a toner cartridge approaches the end, the amount of toner discharged from the toner cartridge may be reduced. In this case, the toner cartridge may be removed temporarily from the image forming apparatus and shaken and then reloaded in the image forming apparatus. This embodiment discloses a technique for preventing a toner cartridge from being erroneously determined as a non-genuine product when the toner cartridge is reloaded in the image forming apparatus.

The following description is about the toner cartridge 10 Y. The description of the other toner cartridges 10 M to 10 K is duplicate and therefore omitted. With reference to FIG. 8 , a second acquisition unit 35 acquires information about the total amount of toner discharged from the toner cartridge 10 Y.

The second acquisition unit 35 may be realized by the number of rotations detecting unit 13 Y and the control unit 19 in cooperation with each other. In the IC chip 14 Y, the result of detection by the number of rotations detecting unit 13 Y is stored.

With reference to FIG. 9 , in ACT 301 , the control unit 19 determines whether the toner cartridge 10 Y is loaded on the loading unit 1 Ya or not. When the toner cartridge 10 Y is loaded on the loading unit 1 Ya, the control unit 19 goes to ACT 302 .

In ACT 302 , the control unit 19 specifies the current time based on the count result from the timer 18 and goes to ACT 303 . In ACT 303 , the control unit 19 acquires all the authentication information belonging to the allowable time zone from the apparatus storage unit 17 and goes to ACT 304 .

In ACT 304 , the control unit 19 acquires the first information stored in the IC chip 14 Y and goes to ACT 305 . In ACT 305 , the control unit 19 compares the authentication information belonging to the allowable time zone with the first information. When these pieces of information are identical, the control unit 19 returns to ACT 301 . When these pieces of information are not identical, the control unit 19 goes to ACT 306 .

In ACT 306 , the control unit 19 calculates the total amount of toner supplied, based on the result of detection stored in the IC chip 14 Y, and goes to ACT 307 .

In ACT 307 , the control unit 19 determines whether the total amount of toner supplied exceeds a threshold value or not. When the total amount supplied exceeds the threshold value, the control unit 19 goes to ACT 308 . When the total amount supplied does not exceed the threshold value, the control unit 19 returns to ACT 301 . Here, the threshold value corresponds to the total amount of toner stored in the toner cartridge 10 Y.

In ACT 308 , the control unit 19 displays alert information on the display unit 90 . The alert information may be character information indicating that the toner is not a genuine product.

The invention can be carried out in various other forms without departing from the spirit or principal features of the invention. Therefore, the above embodiments are simply examples in every respect and should not be interpreted as limiting the invention. The scope of the invention is defined by the attached claims and is not limited by the specification. Moreover, all modifications, various improvements, alterations and changes that fall within the range of equivalents to the claims are considered to be within the scope of the invention.