JP2010217555A - Image forming apparatus and method for determining service life of toner cartridge of the image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To determine a service life of a toner cartridge in consideration of a phenomenon in which toner before it is developed in a developing device is deteriorated with time and by friction. <P>SOLUTION: The image forming apparatus has the developing device which develops an electrostatic latent image on a photoreceptor by the toner to be supplied from the toner cartridge, and is provided with: a toner deterioration determination part 113 which determines the deterioration of the remaining toner in the toner cartridge from the threshold of toner deterioration to be preset; and a toner cartridge life determination part 111 which determines the service life of the toner cartridge from determination results of the toner deterioration determination part 113. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus and a toner cartridge life determination method for an image forming apparatus.

  2. Description of the Related Art Conventionally, in an image forming apparatus that forms an image using toner such as a copying machine or a printer, it is desired that the user can be informed of the amount of toner consumed or the remaining amount for the convenience of maintenance such as toner replenishment. Yes. In general, the amount of toner consumption is notified by detecting the remaining amount of toner in the toner container using a toner amount detection sensor and notifying the detection result, and the toner based on image information. There is one that calculates and notifies the consumption amount of

  What calculates toner consumption based on image information is a toner consumption prediction which is an estimated amount of toner consumed when toner of a developing device as a developing unit adheres to a photosensitive member as a latent image carrier. Calculate the amount. As the toner consumed by adhering to the photoconductor, the toner adheres to a non-latent image portion other than the latent image portion on the photoconductor separately from the toner consumed to form the latent image as a toner image. Some toner is consumed by a phenomenon called “fogging”. In order to bring the predicted amount of consumed toner closer to the actual amount of consumed toner, a toner consumption predicted amount calculation method that considers not only the amount of toner consumed as a toner image but also the amount of toner consumed by “fogging” Is disclosed (for example, see Patent Document 1).

  In addition, a technique is known in which the calculation of the remaining amount of developing roller driving time is adapted to the actual usage in determining the life of the toner cartridge. A toner cartridge life management device is disclosed that excludes the developing roller driving time for patch image formation when accumulating the developing roller driving time (see, for example, Patent Document 2). Further, a toner consumption calculation device is disclosed that is configured to be compatible with toner cartridge replacement even when a reading error occurs in the cumulative count value of the toner counter (see, for example, Patent Document 3).

  However, in the conventional technology for determining the life of the toner cartridge as described above, even if the amount of toner consumed is predicted and the remaining amount of toner is notified, there are cases where the notification cannot be made accurately. This is when the toner before development in the developing device deteriorates due to aging or friction and cannot adhere to the latent image carrier sufficiently and image deterioration occurs before notifying the user of the life of the toner cartridge. There was a problem such as.

  The present invention has been made in view of the above, and an object thereof is to determine the life of a toner cartridge in consideration of a phenomenon in which toner before development in a developing device deteriorates due to aging or friction. .

  In order to solve the above-described problems and achieve the object, the present invention provides an image forming apparatus having a developing device that develops an electrostatic latent image on a photosensitive member with toner supplied from a toner cartridge, which is set in advance. Toner deterioration determining means for determining the deterioration of the remaining toner in the toner cartridge from the threshold of toner deterioration to be performed, and toner cartridge life determining means for determining the toner cartridge life from the determination result of the toner deterioration determining means. It is characterized by that.

  The image forming apparatus according to the present invention determines the life of the toner cartridge in consideration of the phenomenon that the toner before development in the developing device deteriorates due to aging or friction. There is an effect that it can be raised.

FIG. 1 is an explanatory diagram showing a schematic configuration of the copying machine according to this embodiment. FIG. 2 is an explanatory diagram showing an enlarged part of the internal configuration of the printer unit of FIG. FIG. 3 is an explanatory view showing the Y process unit in an enlarged manner together with the intermediate transfer belt. FIG. 4 is an explanatory diagram showing the configuration of the developing device for Y. FIG. 5 is a block diagram illustrating a system configuration of the image forming apparatus. FIG. 6 is a block diagram illustrating a functional configuration example of a main part of the image forming apparatus according to this embodiment. FIG. 7 is a flowchart showing an operation example 1 of the image forming apparatus according to this embodiment. FIG. 8 is a flowchart showing an operation example 2 of the image forming apparatus according to this embodiment. FIG. 9 is a flowchart showing the toner cartridge installation counting process in FIG. FIG. 10 is a flowchart showing an operation example 3 of the image forming apparatus according to this embodiment. FIG. 11 is a flowchart showing processing for calculating the rotation distance of the toner cartridge in FIG. FIG. 12 is a flowchart showing an operation example 4 of the image forming apparatus according to this embodiment. FIG. 13 is a flowchart showing the density adjustment processing in FIG. FIG. 14 is a flowchart showing an operation example 5 of the image forming apparatus according to this embodiment.

  Exemplary embodiments of an image forming apparatus and a toner cartridge life determination method for the image forming apparatus according to the present invention will be explained below in detail with reference to the accompanying drawings.

(Embodiment)
FIG. 1 is an explanatory diagram showing a schematic configuration of a copying machine according to this embodiment. The copying machine includes a printer unit 1 that forms an image on recording paper, a paper feeding device 200 that supplies the recording paper P to the printer unit 1, a scanner 300 that reads a document image, and automatically feeds a document to the scanner 300. An automatic document feeder 400 is provided.

  The scanner 300 is placed on the contact glass 301 as the first traveling body 303 equipped with a document illumination light source or mirror and the second traveling body 304 equipped with a plurality of reflecting mirrors reciprocate. Scanning of a document (not shown) is performed. The scanning light sent out from the second traveling body 304 is condensed on the imaging surface of the reading sensor 306 installed behind the imaging lens 305 and then read as an image signal by the reading sensor 306.

  On the side surface of the housing of the printer unit 1, a manual feed tray 2 for manually placing the recording paper P to be fed into the housing, and a paper discharge tray 3 for stacking the recording paper P after image formation discharged from the housing. Is provided.

  FIG. 2 is an explanatory diagram showing an enlarged part of the internal configuration of the printer unit 1. In the housing of the printer unit 1, there is disposed a transfer unit 50 as transfer means for stretching an endless intermediate transfer belt 51 as an image carrier by a plurality of stretching rollers. The intermediate transfer belt 51 is driven by a driving roller 52, a secondary transfer backup roller 53, a driven roller 54, and four primary transfer rollers 55Y, 55Y, 55K, which are driven to rotate in a clockwise direction by a driving unit (not shown). While being stretched, the drive roller 52 is rotated endlessly in the clockwise direction in the drawing. Note that the suffixes Y, C, M, and K attached to the ends of the symbols of the primary transfer roller indicate the members for yellow, cyan, magenta, and black. Hereinafter, the subscripts Y, C, M, and K attached to the ends of the symbols are the same.

  The intermediate transfer belt 51 is greatly curved at the portions where the intermediate transfer belt 51 is wound around the driving roller 52, the secondary transfer backup roller 53, and the driven roller 54, so that the intermediate transfer belt 51 is stretched in an inverted triangular posture with the bottom side directed vertically upward. ing. The belt upper stretch surface corresponding to the base of the inverted triangle extends in the horizontal direction. Above the belt upper stretch surface, four process units 10Y, 10C, 10M, and 10K are provided on the upper stretch surface. It arrange | positions so that it may align with a horizontal direction along the extending direction.

  In FIG. 1 described above, an optical writing unit 68 is disposed above the four process units 10Y, 10C, 10M, and 10K. The optical writing unit 68 emits four writing lights L by driving four semiconductor lasers (not shown) by a laser control unit (not shown) based on the image information of the original read by the scanner 300. Then, the drum-shaped photoconductors 11Y, 11C, 11M, and 11K serving as latent image carriers of the process units 10Y, 10C, 10M, and 10K are scanned in the dark by the writing light L, respectively. , K, electrostatic latent images for Y, C, M, and K are written.

  In this embodiment, the optical writing unit 68 performs optical scanning by deflecting a laser beam emitted from a semiconductor laser by a polygon mirror (not shown) and reflecting it with a reflection mirror (not shown) or passing it through an optical lens. Something is used. Instead of such a configuration, an LED array that performs optical scanning may be used.

  FIG. 3 is an explanatory diagram showing the Y process unit 10Y together with the intermediate transfer belt 51 in an enlarged manner. The Y process unit 10Y includes a charging member 12Y, a charge eliminating device 13Y, a drum cleaning device 14Y, a developing device 20Y as developing means, a potential sensor 49Y, and the like around a drum-shaped photoconductor 11Y. These are integrally attached to and detached from the printer unit while being held by a casing as a common holding body.

  The charging member 12Y is a roller-like member that is rotatably supported by a bearing (not shown) while being in contact with the photoreceptor 11Y. The surface of the photoconductor 11Y is uniformly charged to the same polarity as, for example, the charge polarity of Y toner by rotating in contact with the photoconductor 11Y while a charging bias is applied by a bias supply means (not shown). Instead of the charging member 12Y having such a configuration, a scorotron charger or the like that performs a uniform charging process on the photoreceptor 11Y in a non-contact manner may be employed.

  A developing device 20Y in which a Y developer containing a magnetic carrier (not shown) and non-magnetic Y toner is contained in a casing 21Y has a developer conveying device 22Y and a developing unit 23Y. In the developing unit 23Y, a developing sleeve 24Y as a developer carrying member that is endlessly moved by being rotated by a driving unit (not shown) exposes a part of its peripheral surface to the outside through an opening provided in the casing 21Y. ing. As a result, a developing region is formed in which the photoconductor 11Y and the developing sleeve 24Y face each other with a predetermined gap.

  Inside the developing sleeve 24Y made of a non-magnetic hollow pipe-like member, a magnet roller (not shown) having a plurality of magnetic poles arranged in the circumferential direction is fixed so as not to rotate with the developing sleeve 24Y. The developing sleeve 24Y is driven to rotate while adsorbing the Y developer in the developer conveying device 22Y, which will be described later, to the surface by the magnetic force generated by the magnet roller, thereby pumping the Y developer from the developer conveying device 22Y. Then, the Y developer conveyed toward the developing area as the developing sleeve 24Y rotates, the doctor blade 25Y having the tip opposed to the surface of the developing sleeve 24Y with a predetermined gap, and the sleeve A doctor gap formed between the surface and the surface is entered. At this time, the layer thickness on the sleeve is regulated to substantially the same thickness as the doctor gap. When the developing sleeve 24Y is rotated and conveyed to the vicinity of the developing area facing the photoconductor 11Y, it receives a magnetic force of a developing magnetic pole (not shown) of the magnet roller and rises on the sleeve to become a magnetic brush. .

  For example, a developing bias having the same polarity as the toner charging polarity is applied to the developing sleeve 24Y by a bias supply means (not shown). As a result, in the development region, non-development in which Y toner is electrostatically moved from the non-image portion side to the sleeve side between the surface of the development sleeve 24Y and the non-image portion (uniformly charged portion = background portion) of the photoreceptor 11Y. Potential acts. Further, a developing potential for electrostatically moving Y toner from the sleeve side toward the electrostatic latent image acts between the surface of the developing sleeve 24Y and the electrostatic latent image on the photoreceptor 11Y. The Y toner in the Y developer is transferred to the electrostatic latent image by the action of the developing potential, so that the electrostatic latent image on the photoreceptor 11Y is developed into the Y toner image.

  The Y developer that has passed through the developing area as the developing sleeve 24Y rotates is separated from the developing sleeve 24Y due to the influence of the repulsive magnetic field formed between the repelling magnetic poles provided in the magnet roller (not shown). The developer returns to the developer conveying device 22Y.

  The developer conveying device 22Y includes two first screw members 26Y, a second screw member 32Y, a partition wall interposed between the two screw members, a toner concentration detection sensor 45Y including a magnetic permeability sensor, and the like. The partition wall divides the first transport chamber, which is a developer transport section, in which the first screw member 26Y is accommodated, and the second transport chamber, which is a developer transport section in which the second screw member 32Y is accommodated. In the region facing both ends in the axial direction of the screw member, both the transfer chambers are communicated with each other through an opening (not shown).

  The first screw member 26Y and the second screw member 32Y as the agitating / conveying members are respectively provided with a rod-like rotary shaft member whose both ends are rotatably supported by a bearing (not shown), and a spiral projection on the peripheral surface thereof. And a spiral blade. Then, as it is driven to rotate by a driving means (not shown), the Y developer is conveyed in the rotation axis direction by the spiral blade.

  In the first transport chamber in which the first screw member 26Y is accommodated, the Y developer is transported from the near side to the far side in the direction orthogonal to the drawing surface as the first screw member 26Y is driven to rotate. . And if it conveys to the edge part vicinity of the back | inner side of casing 21Y, it will approach into a 2nd conveyance chamber via the opening which is not provided in the partition wall.

  The above-described developing unit 23Y is formed above the second transfer chamber in which the second screw member 32Y is accommodated, and the second transfer chamber and the developing unit 23Y communicate with each other in the entire area of the opposing part. ing. As a result, the second screw member 32Y and the developing sleeve 24Y disposed obliquely above the second screw member 32Y face each other while maintaining a parallel relationship. In the second transport chamber, the Y developer is transported from the back side to the near side in the direction orthogonal to the drawing sheet as the second screw member 32Y is driven to rotate. In this transport process, the Y developer around the rotation direction of the second screw member 32Y is appropriately pumped up to the developing sleeve 24Y, and the developed Y developer is appropriately collected from the developing sleeve 24Y. Then, the Y developer transported to the vicinity of the near end of the second transport chamber in the drawing returns to the first transport chamber through an opening (not shown) provided in the partition wall.

  A toner concentration detection sensor 45Y as a toner concentration detection means including a magnetic permeability sensor is fixed to the lower wall of the first conveyance chamber, and the toner concentration of the Y developer conveyed by the first screw member 26Y is lowered. And outputs a voltage according to the detection result. A control unit (not shown) replenishes an appropriate amount of Y toner into the first transfer chamber by driving a Y toner supply device (not shown) as necessary based on the output voltage value from the toner concentration detection sensor 45Y. As a result, the toner concentration of the Y developer, which has been lowered with the development, is recovered.

  The Y toner image formed on the photoreceptor 11Y is primarily transferred onto the intermediate transfer belt 51 at a Y primary transfer nip described later. The transfer residual toner that has not been primarily transferred onto the intermediate transfer belt 51 adheres to the surface of the photoreceptor 11Y after passing through the primary transfer process.

  The drum cleaning device 14Y cantilever-supports a cleaning blade 15Y made of, for example, polyurethane rubber, and the free end thereof is in contact with the surface of the photoreceptor 11Y. Further, a brush tip end side of a brush roller 16Y having a rotating shaft member that is driven to rotate by a driving means (not shown) and an infinite number of conductive brushes erected on the peripheral surface thereof is brought into contact with the photoreceptor 11Y. Yes. Then, the transfer residual toner described above is scraped off from the surface of the photoreceptor 11Y by the cleaning blade 15Y and the brush roller 16Y. A cleaning bias is applied to the brush roller 16Y via a metal electric field roller 17Y that is in contact with the brush roller 16Y, and the tip of the scraper 18Y is pressed against the electric field roller 17Y. The transfer residual toner scraped off from the photoconductor 11Y by the cleaning blade 15Y and the brush roller 16Y passes through the brush roller 16Y and the electric field roller 17Y, and then is scraped off from the electric field roller 17Y by the scraper 18Y and is placed on the recovery screw 19Y. Fall. Then, after the recovery screw 19Y is driven to rotate, the recovery screw 19Y is discharged out of the casing, and then returned to the developer transport device 22Y via a toner recycling transport means (not shown).

  The surface of the photoreceptor 11Y from which the residual toner after the transfer processing is cleaned by the drum cleaning device 14Y is discharged by the discharging device 13Y including a discharging lamp, and then is uniformly charged again by the charging member 12Y.

  Further, the potential of the non-image portion of the photoreceptor 11Y that has passed the optical writing position by the writing light L is detected by the potential sensor 49Y, and the detection result is sent to a control unit (not shown).

  Although the Y process unit 10Y has been described in detail, the process units (10C, M, K) of other colors have the same configuration as that of Y except that the color of the toner to be used is different. .

  In FIG. 2 shown above, the photoconductors 11Y, C, M, and K of the process units 10Y, 10C, 10M, and 10K are in contact with the upper stretched surface of the intermediate transfer belt 51 that is endlessly moved in the clockwise direction. Rotating to form primary transfer nips for Y, C, M, and K. On the back side of these primary transfer nips for Y, C, M, and K, the above-described primary transfer rollers 55Y, 55C, 55M, and 55K are in contact with the back surface of the intermediate transfer belt 51. A primary transfer bias having a polarity opposite to the charging polarity of the toner is applied to each of the primary transfer rollers 55Y, 55C, 55M, 55K by a bias supply unit (not shown). Due to this primary transfer bias, a primary transfer electric field is formed in the primary transfer nips for Y, C, M, and K to electrostatically move the toner from the photoreceptor side to the belt side. The Y, C, M, and K toner images formed on the photoreceptors 11Y, 11C, 11M, and 11K are primary for Y, C, M, and K as the photoreceptors 11Y, 11C, 11M, and 11K rotate. When entering the transfer nip, primary transfer is performed by sequentially superimposing on the intermediate transfer belt 51 by the action of the primary transfer electric field and nip pressure. As a result, a four-color superimposed toner image (hereinafter referred to as a four-color toner image) is formed on the front surface (loop outer peripheral surface) of the intermediate transfer belt 51. Instead of the primary transfer rollers 55Y, 55C, 55M, 55K, a conductive brush to which a primary transfer bias is applied, a non-contact type corona charger, or the like may be employed.

  On the right side of the K process unit 10K in the figure, an image density detector 69 is disposed so as to face the front surface of the intermediate transfer belt 51 with a predetermined gap. The image density detection unit 69 outputs a voltage corresponding to the toner adhesion amount per unit area with respect to a later-described reference toner patch image transferred to the intermediate transfer belt 51.

  A secondary transfer roller 56 is disposed below the intermediate transfer belt 51. The secondary transfer roller 56 abuts against the front surface of the intermediate transfer belt 51 while being driven to rotate counterclockwise in the drawing by a driving means (not shown). A secondary transfer nip is formed in contact therewith. A secondary transfer backup roller 53 wraps around the intermediate transfer belt 51 on the back side of the secondary transfer nip.

  A secondary transfer bias having the same polarity as the toner charging polarity is applied to the secondary transfer backup roller 53 by a secondary transfer power source (not shown). On the other hand, the secondary transfer roller 56 that is a contact member that is in contact with the front surface of the belt and forms a secondary transfer nip is grounded. As a result, a secondary transfer electric field is formed between the secondary transfer backup roller 53 and the secondary transfer roller 56. The four-color toner image formed on the front surface of the intermediate transfer belt 51 enters the secondary transfer nip as the intermediate transfer belt 51 moves endlessly.

  In FIG. 1 described above, the paper feeding device 200 is fed with a paper feeding cassette 201 for storing the recording paper P, and a paper feeding roller 202 for feeding the recording paper P stored in these paper feeding cassettes 201 out of the cassette. A plurality of separation roller pairs 203 for separating the recording paper P one by one, a plurality of conveyance roller pairs 205 for conveying the separated recording paper P along the delivery path 204, and the like are provided. The sheet feeding device 200 is disposed directly below the printer unit 1 as shown in the figure. The feeding path 204 of the paper feeding device 200 is connected to the paper feeding path 70 of the printer unit 1. As a result, the recording paper P delivered from the paper feed cassette 201 of the paper feed device 200 is sent into the paper feed path 70 of the printer unit 1 via the feed path 204.

  Near the end of the paper feed path 70 of the printer unit 1, a registration roller pair 71 is disposed as a feeding means, and the recording paper P sandwiched between the rollers is converted into a four-color toner image on the intermediate transfer belt 51. The sheet is fed into the secondary transfer nip at a timing that can be synchronized. In the secondary transfer nip, the four-color toner images on the intermediate transfer belt 51 are collectively transferred to the recording paper P due to the influence of the secondary transfer electric field and the nip pressure, and combined with the white color of the recording paper P, Become. The recording paper P on which the full-color image is formed in this way is separated from the intermediate transfer belt 51 when discharged from the secondary transfer nip.

  On the left side of the secondary transfer nip in the figure, a conveyor belt unit 75 is provided that moves the endless paper conveyor belt 76 endlessly in the counterclockwise direction in the figure while being stretched by a plurality of stretching rollers. . The recording paper P separated from the intermediate transfer belt 51 is transferred to the upper stretched surface of the paper conveying belt 76 and conveyed toward the fixing device 80.

  The recording paper P sent into the fixing device 80 is sandwiched in a fixing nip formed by a heating roller 81 containing a heat source such as a halogen heater (not shown) and a pressure roller 82 pressed toward the heating roller 81. Then, the full color image is fixed on the surface by being heated while being pressurized, and is sent to the outside of the fixing device 80.

  On the surface of the intermediate transfer belt 51 after passing through the secondary transfer nip, a slight amount of secondary transfer residual toner that has not been transferred to the recording paper P adheres. The secondary transfer residual toner is removed from the belt by a belt cleaning device 57 that is in contact with the front surface of the intermediate transfer belt 51.

  A switchback device 85 is disposed below the fixing device 80. When the recording paper P discharged from the fixing device 80 reaches the conveyance path switching position by the swingable switching claw 86, the paper discharge roller pair 87 or the switchback device according to the swing stop position of the switching claw 86. Sent to 85. When the paper is sent toward the paper discharge roller pair 87, the paper is discharged out of the apparatus and then stacked on the paper discharge tray 3.

  On the other hand, when it is sent toward the switchback device 85, it is turned upside down by the switchback conveyance by the switchback device 85 and then conveyed toward the registration roller pair 71 again. Then, it enters the secondary transfer nip again, and a full-color image is formed on the other side.

  The recording paper P manually fed onto the manual feed tray 2 provided on the side surface of the housing of the printer unit 1 passes through the manual feed roller 72 and the manual separation roller pair 73 and then toward the registration roller pair 71. Sent.

  When copying a document by the copying machine according to this embodiment, first, the document is set on the document table 401 of the automatic document feeder 400. Alternatively, the automatic document feeder 400 is opened, a document is set on the contact glass 301 of the scanner 300, and the automatic document feeder 400 is closed and pressed. Thereafter, when a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is sent into the contact glass 301. Then, the scanner 300 is driven, and scanning by the first traveling body 303 and the second traveling body 304 is started. At substantially the same time, driving of the transfer unit 50 and each color process unit 10Y, C, M, K starts. Furthermore, the feeding of the recording paper P from the paper feeding device 200 is also started. When recording paper P not set in the paper feed cassette 201 is used, the recording paper P set on the manual feed tray 2 is sent out.

  As will be described later, the printer unit 1 of the copying machine includes a CPU (Central Processing Unit), a ROM (Read Only Memory) as a data storage unit for storing control programs, parameters, and the like, and a RAM (Random Access Memory). ), An I / O interface, and the like. Based on the control program stored in the ROM, the driving of various devices in the printer unit 1 is controlled.

  At one end portion in the width direction of the intermediate transfer belt 51, a K-color toner patch pattern is formed at a predetermined timing. The K color toner patch pattern is composed of a plurality of K reference toner patch images arranged at a predetermined interval in the belt moving direction. Further, Y, M, and C toner patch patterns are formed at predetermined timings on the other end in the width direction of the intermediate transfer belt 51, respectively. These toner patch patterns are also composed of a plurality of Y, M, and C toner patch images arranged at predetermined intervals in the belt moving direction. In this copying machine, each toner patch pattern is composed of seven reference toner patch images, but the number of reference toner patch images constituting the toner patch pattern may be larger or smaller. Hereinafter, the three colors Y, M, and C are collectively referred to as color colors.

  2 includes a light emitting element (not shown) that emits light toward the belt surface near one end in the width direction of the intermediate transfer belt 51 and specularly reflected light that is specularly reflected on the belt surface. A first optical sensor having a regular reflection light receiving element (not shown) that receives the light. In addition, near the other end in the width direction of the intermediate transfer belt 51, a light emitting element (not shown) that emits light toward the belt surface and a diffusion light receiving element (not shown) that receives diffusely reflected light diffusely reflected on the belt surface are provided. And a second optical sensor.

  When the individual K reference toner patch images in the K color toner patch pattern formed at one end in the width direction of the intermediate transfer belt 51 move directly below the image density detection unit 69 along with the endless movement of the belt. The output voltage value from one optical sensor is significantly reduced. This is because the light emitted from the light emitting element of the first optical sensor is blocked by the K toner layer of the K reference toner patch image and hardly reflects regularly on the belt surface. The output voltage value from the first optical sensor at this time is a value corresponding to the K toner adhesion amount (K image density) per unit area with respect to the K reference toner patch image. And the control part can grasp | ascertain the K toner adhesion amount with respect to a K reference | standard toner patch image based on the output voltage value from a 1st optical sensor.

  Further, the Y, M, and C reference toner patch images in the color toner patch pattern formed on the other end portion in the width direction of the intermediate transfer belt 51 are transferred to the image density detection unit 69 by the endless movement of the belt. When it moves directly below the second optical sensor, the output voltage value from the second optical sensor significantly increases. This is because the light emitted from the light emitting element of the second optical sensor is diffusely reflected on the surfaces of the Y, M, and C toner layers of the Y, M, and C reference toner patch images and then diffused and reflected as described above. This is because the light is received by the element. The output voltage value from the second optical sensor at this time is a value corresponding to the Y, M, C toner adhesion amount (Y, M, C image density) per unit area with respect to the Y, M, C reference toner patch image. Become. Then, the control unit can grasp the Y, M, and C toner adhesion amounts with respect to the Y, M, and C reference toner patch images based on the output voltage value from the second optical sensor.

  The printer unit 1 supplies Y, M, C, and K toners (not shown) to the developing devices 20Y, M, C, and K of the process units 10Y, M, C, and K, respectively. A toner replenishing device for K is provided. In addition, Y, M, C, and K toner cartridges (not shown) that individually store replenishment Y, M, C, and K are removably attached to the printer unit 1.

  The developing devices 20Y, M, C, and K are toners for Y, M, C, and K, each of which includes a magnetic permeability sensor that detects Y, M, C, and K toner images of the Y, M, C, and K developers inside. It has density detection sensors 45Y, M, C, and K.

  Hereinafter, a Y color developing device will be described as an example. Although not shown in FIG. 3 for the sake of convenience, the developing device 20Y has an initial agent storage portion 27Y as a toner cartridge that stores a Y-color initial agent above the developer transport device 22Y. The initial agent container 27Y and the developer transport device 22Y communicate with each other through an initial agent charging opening. However, in the initial developing device 20Y, the initial agent charging opening is closed by a sealing seal (not shown). . Prior to mounting the new Y process unit 10Y to the printer unit 1, the user pulls out the sealing seal described above from the developing device 20Y, so that the initial agent storage unit 27Y and the developer conveying device 22Y are connected. Communicate. As a result, the initial agent can drop from the initial agent container 27Y to the developer conveying device 22Y. Note that the initial agent container 27Y of the developing device 20Y shown in FIG. 4 is detachable from the developing device main body.

  FIG. 5 is a block diagram illustrating a system configuration of the above-described image forming apparatus. In FIG. 5, the CPU 100 interprets and executes a program command. The operation panel 101 is a panel that allows a user who uses the image forming apparatus to grasp the state of the image forming apparatus and change the operation of the image forming apparatus. The ROM 102 is a read-only semiconductor memory that stores a program executed by the CPU 100. The EEPROM 103 is a storage device that does not erase data even when the power that can be electrically erased (rewritten) is turned off. The RAM 104 is a semiconductor memory used as a working memory that can be read and written by designating an arbitrary address. The image memory 105 is a memory that stores image data to be printed by the image forming apparatus. The I / O 106 controls input / output of electrical components such as sensors, motors, and clutches. The I / F 107 is an interface between the image forming apparatus and a terminal that issues a print request to the image forming apparatus.

  FIG. 6 is a block diagram illustrating a functional configuration example of a main part of the image forming apparatus according to this embodiment. In the following description, the developing device 20 including a toner cartridge is simply referred to as a toner cartridge as appropriate. In FIG. 6, the print job management unit 110 manages the printing order for print jobs requested from the image forming apparatus. The image density detection unit 69 detects the toner density on the intermediate transfer belt 51. The toner life determination unit 111 compares the toner life threshold and the toner consumption amount to determine the toner life. The toner consumption calculation unit 112 calculates the amount of toner consumed from the toner cartridge. The EEPROM 103 stores a toner consumption amount and a toner life threshold value. The toner deterioration determination unit 113 determines the deterioration of the remaining toner in the toner cartridge. A process control (process control) unit 114 adjusts the toner density by a developing bias. The toner cartridge attachment sensor 115 is a sensor that detects attachment of the developing device 20 including the toner cartridge to the main body. Hereinafter, an operation example executed by the CPU 100 as the control unit in the configuration described above will be described.

  The above toner life threshold value is obtained in advance by an evaluation experiment or the like and stored in the EEPROM 103. For example, the relationship between the operating time of the developing device and the toner charging property, the relationship between the mounting time of the developing device and the toner charging property, the relationship between the image density and the developing bias, or the relationship with the developing potential is obtained. From this toner life threshold, an appropriate range is determined and toner deterioration is determined.

(Operation example 1)
FIG. 7 is a flowchart showing an operation example 1 of the image forming apparatus according to this embodiment. First, it is determined whether or not a print request is generated (step S11). When a print request is generated (determination Yes), the toner deterioration determination unit 113 evaluates the deterioration of the remaining toner in each color toner cartridge, and the result is stored in the EEPROM 103. (Step S12). Subsequently, printing is started (step S13). During the printing operation, the toner consumption amount calculation unit 112 calculates the toner consumption amount, and the result is stored in the EEPROM 103 (steps S14 and S15). After finishing the printing operation, the toner life determination unit 111 acquires information on toner deterioration and toner consumption from the EEPROM 103, and determines whether or not the remaining toner is deteriorated (step S16). Here, when it is determined that the remaining toner is deteriorated (determination Yes), when the toner is deteriorated based on the information of toner deterioration, the toner life is compared with the toner life threshold value when the deterioration is evaluated in advance through experiments. Is determined (step S17). On the other hand, when it is determined that the remaining toner has not deteriorated (determination No), the toner cartridge life is determined based on the normal toner life threshold (step S18).

  Therefore, since the life of the toner cartridge is determined in consideration of the phenomenon that the toner before development in the developing device 20 deteriorates due to aging or friction, it is possible to improve the accuracy of the toner cartridge life determination.

(Operation example 2)
In order to detect a phenomenon in which toner before development in the developing device deteriorates with time or friction, it is necessary to install a high-performance sensor, which is expensive. Accordingly, the life of the toner cartridge is determined by predicting a phenomenon in which the toner before development in the developing device deteriorates with time or friction depending on the usage time of the developing device.

  FIG. 8 is a flowchart showing an operation example 2 of the image forming apparatus according to this embodiment. First, the toner deterioration determination unit 113 measures the time during which the developing device 20 including the toner cartridge is mounted at regular intervals from the detection time by the toner cartridge mounting sensor 115, and stores the result in the EEPROM 103 (step S21). . It is determined whether or not a print request has occurred (step S22). If a print request is generated (determination Yes), the toner deterioration determination unit 113 evaluates the deterioration of the remaining toner in each color toner cartridge and stores the result in the EEPROM 103. (Step S23). Subsequently, the installation of the toner cartridge is counted (see FIG. 9) (step S24), and printing is started (step S25). During the printing operation, the installation of the toner cartridge is counted (see FIG. 9) (step S26), and the toner consumption calculation unit 112 calculates the toner consumption and stores the result in the EEPROM 103 (step S27). Subsequently, the installation of the toner cartridge is counted (see FIG. 9) (step S28), and the printing is finished (step S29). After the printing operation is finished, the toner life determination unit 111 acquires information on toner deterioration and toner consumption from the EEPROM 103, and determines whether or not the remaining toner is deteriorated (step S30). Here, when it is determined that the remaining toner is deteriorated (determination Yes), when the toner is deteriorated based on the information of the toner deterioration, the toner life is compared with the toner life threshold value when the deterioration is evaluated in advance through experiments. Is determined (step S31). On the other hand, when it is determined that the remaining toner has not deteriorated (determination No), the toner cartridge life is determined based on the normal toner life threshold (step S32).

  FIG. 9 is a flowchart showing the toner cartridge installation counting process in FIG. Here, first, the toner deterioration determination unit 113 acquires the mounting time of each color toner cartridge from the EEPROM 103, and determines the deterioration of the remaining toner in each color toner cartridge from the result (step S41). The toner cartridge is set. If so, the result is stored in the EEPROM 103 (step S42).

  Therefore, since the phenomenon that the toner before development in the developing device 20 deteriorates with time or friction is predicted based on the usage time of the developing device 20, the cost can be reduced and the accuracy of toner cartridge life determination can be increased. .

(Operation example 3)
If the phenomenon that the toner before development in the developing device deteriorates with time or friction is predicted based on the usage time of the developing device, it may be unpredictable due to the difference in the printing frequency of the user, and the toner cartridge life judgment is accurate There are things that cannot be done. Accordingly, the life of the toner cartridge is determined by predicting a phenomenon in which the toner before development in the developing device deteriorates with time or friction depending on the rotation time of the developing roller in the developing device.

  FIG. 10 is a flowchart showing an operation example 3 of the image forming apparatus according to this embodiment. First, when the rotating member including the developing sleeve (developing roller) 24Y in the developing device 20 rotates, the toner deterioration determining unit 113 calculates the rotation distance (see FIG. 11), and stores the result in the EEPROM 103 (step). S51). It is determined whether or not a print request has occurred (step S52). When a print request is generated (determination Yes), the toner deterioration determination unit 113 evaluates the deterioration of the remaining toner in each color toner cartridge and stores the result in the EEPROM 103. (Step S53). Subsequently, when the rotating member including the developing sleeve 24 in the developing device 20Y rotates, the toner deterioration determining unit 113 calculates the rotation distance (see FIG. 11), and stores the result in the EEPROM 103 (step S54). Printing is started (step S55). During the printing operation, the toner deterioration determination unit 111 calculates the rotation distance when the rotating member including the developing sleeve 24 in the developing device 20 rotates (see FIG. 11), and stores the result in the EEPROM 103 (step S56). The toner consumption calculation unit 112 calculates the toner consumption and stores the result in the EEPROM 103 (step S57). Subsequently, when the rotating member including the developing sleeve 24 in the developing device 20 rotates, the toner deterioration determining unit 111 calculates the rotating distance (see FIG. 11), and stores the result in the EEPROM 103 (step S58). Printing is terminated (step S59). After the printing operation is completed, the toner life determination unit 111 acquires information on toner deterioration and toner consumption from the EEPROM 103, and determines whether or not the remaining toner is deteriorated (step S60). Here, when it is determined that the remaining toner is deteriorated (determination Yes), when the toner is deteriorated based on the information of the toner deterioration, the toner life is compared with the toner life threshold value when the deterioration is evaluated in advance through experiments. Is determined (step S61). On the other hand, when it is determined that the remaining toner has not deteriorated (determination No), the toner cartridge life is determined based on the normal toner life threshold (step S62).

  FIG. 11 is a flowchart showing a rotation distance calculation process of the toner cartridge (a rotating member including the developing sleeve (developing roller) 24 in the developing device 20) in FIG. Here, first, it is determined whether or not the developing device 20 is rotating (step S71). If the developing device 20 is rotating here, the rotational distance of the rotating member including the developing sleeve 24 in the developing device 20 is calculated and stored in the EEPROM 103 (step S72).

  Therefore, since the phenomenon that the toner before development in the developing device 20 deteriorates with time and friction is predicted from the rotation distance of the developing sleeve 24, the cost can be reduced and the accuracy of the toner cartridge life determination can be increased. .

(Operation example 4)
If the phenomenon that the toner before development in the developing device deteriorates with time or friction is predicted based on the rotation time of the developing device, there is a possibility that the prediction may be lost depending on the usage environment of the image forming device, and the life determination of the toner cartridge is accurate There are things that cannot be done. Therefore, a phenomenon in which the toner before development in the developing device deteriorates with time or friction is predicted based on the result of reading the density of the formed image with a sensor, and the life of the toner cartridge is determined.

  FIG. 12 is a flowchart showing an operation example 4 of the image forming apparatus according to this embodiment. First, it is determined whether the developing device 20 including a toner cartridge (hereinafter simply referred to as a toner cartridge) is new or has been printed for 100 pages (step S81). If it is determined that the printer is new or has been printed 100 pages, the image density is adjusted by the control unit 114 to detect the developing bias at which the density is optimum (see FIG. 13), and the result is stored in the EEPROM 103. (Step S82). Subsequently, the toner cartridge rotation distance calculation process shown in FIG. 11 is performed (step S83). It is determined whether or not a print request has occurred (step S84). If a print request is generated (determination Yes), the toner deterioration determination unit 113 evaluates the deterioration of the remaining toner in each color toner cartridge and stores the result in the EEPROM 103. (Step S85). Subsequently, when the rotating member including the developing sleeve 24 in the developing device 20 rotates, the toner deterioration determining unit 113 calculates the rotating distance (see FIG. 11), and stores the result in the EEPROM 103 (step S86). Printing is started (step S87). During the printing operation, the toner deterioration determining unit 113 calculates the rotation distance when the rotating member including the developing sleeve 24 in the developing device 20 rotates (see FIG. 11), and stores the result in the EEPROM 103 (step S88). The toner consumption calculation unit 112 calculates the toner consumption and stores the result in the EPROM 103 (step S89). Subsequently, when the rotating member including the developing sleeve 24 in the developing device 20 rotates, the toner deterioration determining unit 113 calculates the rotation distance (see FIG. 11), and stores the result in the EEPROM 103 (step S90). Printing is terminated (step S91). After completing the printing operation, the toner life determination unit 111 acquires information on toner deterioration and toner consumption from the EEPROM 103, and determines whether or not the remaining toner is deteriorated (step S92). Here, when it is determined that the remaining toner is deteriorated (determination Yes), when the toner is deteriorated based on the information of the toner deterioration, the toner life is compared with the toner life threshold value when the deterioration is evaluated in advance through experiments. Is determined (step S93). On the other hand, when it is determined that the remaining toner has not deteriorated (determination No), the life of the toner cartridge is determined based on the normal toner life threshold (step S94).

  FIG. 13 is a flowchart showing the density adjustment processing in step S82 in FIG. First, density adjustment is performed within a predetermined range (steps S101 and S102), and it is determined whether or not the toner cartridge is new (step S103). If it is determined that the toner cartridge is new (determination Yes), the developing bias value when the toner cartridge is new is stored in the EEPROM 103 (step S104). On the other hand, if the toner cartridge is not new in step S103 (determination No), the developing bias is optimally adjusted, the developing bias value is detected, and the result is stored in the EEPROM 103 (step S105).

  Accordingly, since the density of the image in which the toner before being developed in the developing device 20 is deteriorated due to aging or friction is adjusted by the developing bias, the density is predicted based on the result read by the image density detecting unit 69. The accuracy of determining the life of the toner cartridge can be increased.

(Operation example 5)
Even if it is predicted that the toner before development in the developing device has deteriorated due to aging or friction, and the result is taken into account in determining the life of the toner cartridge, the life of the toner cartridge is accurately determined by the state of deterioration. There are things that cannot be done. Therefore, the state in which the toner before development in the developing device has deteriorated due to aging or friction is evaluated, and the threshold of the toner consumption amount for judging the life of the toner cartridge is changed according to the result, and the toner cartridge Judge life.

  FIG. 14 is a flowchart showing an operation example 5 of the image forming apparatus according to this embodiment. First, the toner deterioration determination unit 113 measures the time during which the developing device 20 including the toner cartridge is mounted at regular intervals from the detection time by the toner cartridge mounting sensor 115, and stores the result in the EEPROM 103 (step S111). . It is determined whether or not a print request has occurred (step S112). If a print request is generated (determination Yes), the toner deterioration determination unit 113 evaluates the deterioration of the remaining toner in each color toner cartridge and stores the result in the EEPROM 103. (Step 113). Subsequently, the installation of the toner cartridge is counted (see FIG. 9) (step S114), and printing is started (step S115). During the printing operation, the installation of the toner cartridge is counted (see FIG. 9) (step S116), and the toner consumption calculation unit 112 calculates the toner consumption and stores the result in the EPROM 103 (step S117). Subsequently, the installation of the toner cartridge is counted (see FIG. 9) (step S118), and the printing is finished (step S119). After the printing operation is completed, the toner life determination unit 111 acquires toner deterioration and toner consumption information from the EEPROM 103, calculates an optimum toner life threshold from the toner deterioration information (step S120), and determines the toner life. (Step S121).

  Therefore, the state in which the toner before development in the developing device 20 is deteriorated due to aging or friction is evaluated, and the toner consumption threshold value for judging the life of the toner cartridge is changed according to the result, thereby changing the toner cartridge. Therefore, it is possible to increase the accuracy of the toner cartridge life determination.

  As described above, the image forming apparatus and the toner cartridge life determination method of the image forming apparatus according to the present invention are useful for image forming apparatuses such as copying machines and printers. It is suitable for judging the life of the toner cartridge of the developing device in consideration.

69 Image Density Detection Unit 100 Control Unit 101 Operation Panel 105 EEPROM
111 Toner Life Judgment Unit 112 Toner Consumption Calculation Unit 113 Toner Degradation Judgment Unit 114 Process Control Unit 115 Toner Cartridge Mounting Sensor

JP 2008-26844 A JP 2004-347933 A JP 2004-354666 A

Claims (7)

An image forming apparatus having a developing device that develops an electrostatic latent image on a photoreceptor with toner supplied from a toner cartridge,
Toner deterioration determining means for determining the deterioration of the remaining toner in the toner cartridge from a preset toner deterioration threshold;
Toner cartridge life determination means for determining the toner cartridge life from the determination result of the toner deterioration determination means;
An image forming apparatus comprising:   The image forming apparatus according to claim 1, wherein the toner deterioration determination unit determines a state of a remaining amount of toner in the toner cartridge from a usage time of the developing device.   The image forming apparatus according to claim 1, wherein the toner deterioration determining unit determines a state of a remaining amount of toner in the toner cartridge from a rotation distance of a rotating member in the developing device.   The image forming apparatus according to claim 1, wherein the toner deterioration determining unit determines a state of a remaining amount of toner in the toner cartridge from a developing bias value in a density adjustment process of the developing device.   The image forming apparatus according to claim 1, wherein the toner deterioration determining unit determines a state of a remaining amount of toner in the toner cartridge from a density value of an image formed on the photoconductor.   The lifetime of the toner cartridge is determined to be a lifetime when the amount of toner consumed from the toner cartridge exceeds a certain threshold value. The image forming apparatus according to claim 1, wherein the value of is changed. A toner cartridge life determination method for an image forming apparatus having a developing device that develops an electrostatic latent image on a photoreceptor with toner supplied from a toner cartridge,
A toner deterioration determining step in which the toner deterioration determining means determines the deterioration of the remaining toner in the toner cartridge from a preset toner deterioration threshold;
A toner cartridge life determination step in which a toner cartridge life determination means determines the toner cartridge life from the determination result of the toner deterioration determination step;
A toner cartridge life determination method for an image forming apparatus, comprising:

Images