JP2014215601A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus that stirs a developer in a developer storage container by motor drive, and prevents, when a load is applied to a motor due to the adhesion of toner, the occurrence of trouble in the procedure of cancelling abnormality.SOLUTION: An image forming apparatus includes a control unit 210 as determination means for determining abnormality of a supply drive motor 81 on the basis of a detection result of a current value that is detected via a voltage detection element of a motor driver 88. The control unit 210 determines the abnormality of the supply drive motor 81 when the number of load detection in the case where the voltage detection element of the motor driver 88 detects that the load applied to the supply drive motor 81 is equal to or more than a fixed level exceeds the preset number of times determined in advance. The control unit 210 then determines the abnormality of a motor lock without fail when the number of times of abnormality detection to detect the abnormal load applied to the supply drive motor 81 reaches the preset number of times 5 determined in advance, and controls the image forming apparatus to be in an operation stop state while displaying service calls.

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus such as a printer, a copier, a facsimile machine, a plotter, or a multifunction machine having a plurality of functions.

  In an electrophotographic image forming apparatus such as a printer, a copying machine, a facsimile machine, a plotter, or a multi-function machine having a plurality of functions, a developer is stored in order to replenish a developer such as toner. A developer storage container that can be attached to and detached from the apparatus main body is used. Many devices including a stirring member that stirs a developer containing toner stored in a developer storage container are known, including Patent Document 1. Note that the developer storage container is also referred to as a toner cartridge or a toner bottle in Patent Document 1.

  Here, when the agitating member is rotationally driven by a motor to agitate the developer containing toner, the toner may be fixed. Conventionally, when a load is applied to the motor due to such toner sticking or the like, it is immediately determined that the motor is abnormal, and it takes time to take a procedure for canceling the abnormality.

  The present invention has been made in view of the above-described problems. When the developer in the developer container is agitated by driving the motor, the motor is immediately applied when a load is applied to the motor due to toner adhesion or the like. It is an object of the present invention to provide an image forming apparatus that does not require a troublesome procedure for canceling the abnormality without determining that it is abnormal.

  In order to solve the above-described problems and achieve the above object, the invention described in claim 1 is a development having a developer accommodating portion that accommodates a developer and an agitating member that agitates the developer in the developer accommodating portion. An image forming apparatus comprising: an agent storage container; a drive source that drives the stirring member; and a load detection unit that detects a load applied to the drive source. The drive source based on a detection result of the load detection unit A determination unit configured to determine whether the load applied to the drive source is equal to or greater than a predetermined number of times when the load detection unit detects that the load applied to the drive source is equal to or greater than a predetermined number of times. It is determined that the drive source is abnormal when the value exceeds.

  According to the present invention, when the developer in the developer container is agitated by the drive source, when the load is applied to the drive source due to toner adhesion or the like, it is immediately determined that the drive source is abnormal. There is no trouble and there is no need to take steps to clear the abnormality.

1 is a schematic overall configuration diagram of a copying machine showing an embodiment of the present invention. FIG. 2 is an external perspective view of the copying machine of FIG. 1. It is a schematic block diagram of a developing device and a photoreceptor. FIG. 3 is a perspective view illustrating a configuration of each color developing device and a developer supplying device as a whole for supplying premix toner to the developing device. It is a perspective view of a developer storage container for K color. It is a perspective view of a developer storage container for color. It is sectional drawing of the developing agent storage container for colors. It is a cross-sectional perspective view of a developer storage container for K color. FIG. 4 is an enlarged view showing the vicinity of a coupling attachment portion of a developer storage container for K. It is a perspective view which shows a developing agent supply drive part. It is a front view of a developer supply driving unit. It is a perspective view which shows the structure of a sub hopper. It is a perspective view which shows the internal structure of a sub hopper. It is a figure which shows the developer storage part and conveyance part in a sub hopper. It is a block diagram which shows an example of the principal part structure of the main control system. It is a flowchart which shows the operation | movement order of the motor abnormal current detection of the said one Embodiment. It is a flowchart following FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention including examples will be described in detail with reference to the drawings. In the embodiment and the like, components (members and components) having the same function and shape are denoted by the same reference numerals unless they are confused, and the description thereof is omitted. In order to simplify the drawings and the description, even if the components are to be represented in the drawings, the components that do not need to be specifically described in the drawings may be omitted as appropriate.

First, referring to FIG. 1, as an image forming apparatus to which the present invention is applied, a tandem type in which a plurality of photoconductors are arranged side by side (meaning that they are arranged and arranged and determined). One embodiment of a color laser copying machine (hereinafter simply referred to as “copying machine”) will be described. FIG. 1 is a schematic overall configuration diagram of a copying machine showing an embodiment of the present invention.
The copying machine shown in FIG. 1 includes a printer unit 100 as an image forming unit, a paper feeding device 200 on which the printer unit 100 is placed, a scanner 300 fixed on the printer unit 100, and the like. The copying machine also includes an automatic document feeder 400 fixed on the scanner 300.

  The printer unit 100 includes an image forming unit including four sets of process cartridges 18Y, 18M, 18C, and 18K for forming images of each color of yellow (Y), magenta (M), cyan (C), and black (K). 20 is provided. Y, M, C, and K added as subscripts to the numerals of the respective symbols indicate members for yellow, cyan, magenta, and black (the same applies hereinafter). In addition to the process cartridges 18Y, 18M, 18C, and 18K, the printer unit 100 includes an optical writing unit 21, an intermediate transfer unit 17, a secondary transfer device 22, a registration roller pair 49, a belt fixing type fixing device 25, and the like. It is arranged.

  The optical writing unit 21 includes a light source (not shown), a polygon mirror, an f-θ lens, a reflection mirror, and the like, and irradiates the surface of a photoreceptor to be described later with laser light based on image data.

  The process cartridges 18Y, 18M, 18C, and 18K include a drum-shaped photosensitive member 1 as an image carrier, a charger, a developing device 4, a drum cleaning device, a static eliminator, and the like.

Since the four process cartridges 18Y, 18M, 18C, and 18K have substantially the same configuration except for the color for image formation, except for special contents, the process cartridge 18Y for yellow will be described below as a representative. . Each of the developing devices 4Y, 4M, 4C, and 4K is a two-component developing type developing device that uses different colors of toner, and each color developing device contains a two-component developer containing toner and a carrier. Has been.
The surface of the photoreceptor 1Y is uniformly charged by the charger as the charging means. The surface of the photoreceptor 1 </ b> Y that has been subjected to the charging process is irradiated with laser light modulated and deflected by the optical writing unit 21. Then, the potential of the irradiation part (exposure part) on the surface of the photoreceptor 1Y is attenuated. By this attenuation, an electrostatic latent image for Y is formed on the surface of the photoreceptor 1Y. The formed electrostatic latent image for Y is developed by the developing device 4Y as developing means to become a Y toner image.
The Y toner image formed on the Y photoreceptor 1Y is primarily transferred to an intermediate transfer belt 101 described later. The surface of the photoreceptor 1 </ b> Y after the primary transfer is cleaned with transfer residual toner and the like by a drum cleaning device. In the Y process cartridge 18Y, the photoconductor 1Y cleaned by the drum cleaning device is discharged by a charge eliminator. Then, it is uniformly charged again by the charger and returns to the initial state. The series of processes as described above is the same for the other process cartridges 18M, 18C, and 18K.

The intermediate transfer unit will be described.
The intermediate transfer unit 17 includes an intermediate transfer belt 101, a belt cleaning device 102, and the like. Further, the tension roller 14, the driving roller 15, the secondary transfer backup roller 16, four primary transfer bias rollers 62 </ b> Y, 62 </ b> M, 62 </ b> C, and 62 </ b> K are also provided.
The intermediate transfer belt 101 is stretched (meaning that the intermediate transfer belt 101 is stretched in a tensioned state) by a plurality of rollers including the stretching roller 14. The intermediate transfer belt 101 is endlessly moved (rotated) clockwise in the drawing by the rotation of the driving roller 15 driven by a belt driving motor (not shown).
The four primary transfer bias rollers 62Y, 62M, 62C, and 62K are disposed so as to be in contact with the inner peripheral surface side of the intermediate transfer belt 101, respectively, and apply a primary transfer bias (apply voltage) from a power source (not shown). Mean). Further, the primary transfer bias rollers 62Y, 62M, 62C and 62K press (press and press) the intermediate transfer belt 101 from the inner peripheral surface side toward the photoreceptors 1Y, 1M, 1C and 1K. In each case, a primary transfer nip is formed. In each primary transfer nip, a primary transfer electric field is formed between the photosensitive member and the primary transfer bias roller by the influence and application of the primary transfer bias.

The above-mentioned Y toner image formed on the Y photoconductor 1Y is primarily transferred onto the intermediate transfer belt 101 due to the influence of the primary transfer electric field and the primary nip pressure. On the Y toner image, the M toner image, the C toner image, and the K toner image formed on the M, C, and K photoconductors 1M, 1C, and 1K are sequentially superposed and primarily transferred. By this primary transfer of superposition, a four-color superposed toner image (hereinafter referred to as a four-color toner image), which is a multiple toner image, is formed on the intermediate transfer belt 101.
The four-color toner image superimposed and transferred on the intermediate transfer belt 101 is secondarily transferred to a transfer sheet as a sheet-like recording medium (not shown) at a secondary transfer nip described later. Transfer residual toner or the like remaining on the surface of the intermediate transfer belt 101 after passing through the secondary transfer nip is cleaned by a belt cleaning device 102 disposed in the vicinity of the intermediate transfer belt 101 outside the driving roller 15 on the left side in the drawing. .

Next, the secondary transfer device 22 will be described.
Below the intermediate transfer unit 17 in the figure, a secondary transfer device 22 is disposed in which a paper conveying belt 24 is stretched by two stretching rollers 23. The paper transport belt 24 is moved endlessly in the counterclockwise direction in the drawing in accordance with the rotational drive of at least one of the stretching rollers 23. Of the two stretching rollers 23, one roller 23 disposed on the right side in the drawing is interposed between the secondary transfer backup roller 16 of the intermediate transfer unit 17 and the intermediate transfer belt 101 and the paper transport belt 24. It is sandwiched. By this sandwiching, a secondary transfer nip is formed in which the intermediate transfer belt 101 of the intermediate transfer unit 17 and the paper transport belt 24 of the secondary transfer device 22 come into contact with each other.
A secondary transfer bias having a polarity opposite to that of the toner is applied to the one stretching roller 23 by a power source (not shown). By applying the secondary transfer bias, the four-color toner image on the intermediate transfer belt 101 of the intermediate transfer unit 17 is electrostatically moved from the belt side toward the one stretching roller 23 side in the secondary transfer nip 2. A next transfer electric field is formed. The transfer paper fed into the secondary transfer nip so as to synchronize with the four-color toner image on the intermediate transfer belt 101 by a registration roller pair 49 to be described later is affected by the secondary transfer electric field and the nip pressure. A color toner image is secondarily transferred. Instead of the secondary transfer method in which the secondary transfer bias is applied to one of the stretching rollers 23 as described above, a charger for charging the transfer paper in a non-contact manner may be provided.

  In the paper feeding device 200 provided at the lower part of the copying machine main body, a plurality of paper feeding cassettes 44 in which a plurality of transfer sheets can be stacked and accommodated in a bundle of sheets are arranged so as to overlap in the vertical direction. Has been. Each paper feed cassette 44 presses the paper feed roller 42 against the uppermost transfer paper in the paper bundle. Then, by rotating the paper feed roller 42, the uppermost transfer paper is sent out toward the paper feed path 46.

  The paper feed path 46 that receives the transfer paper fed from the paper feed cassette 44 has a plurality of conveying roller pairs 47 and a registration roller pair 49 provided near the end in the path. Then, the transfer paper is conveyed toward the registration roller pair 49. The transfer sheet conveyed toward the registration roller pair 49 is sandwiched between the rollers of the registration roller pair 49. On the other hand, in the intermediate transfer unit 17, the four-color toner image formed on the intermediate transfer belt 101 enters the secondary transfer nip as the intermediate transfer belt 101 moves endlessly. The registration roller pair 49 sends out the transfer paper sandwiched between the rollers at a timing at which the transfer paper can be brought into close contact with the four-color toner image at the secondary transfer nip. As a result, at the secondary transfer nip, the four-color toner image on the intermediate transfer belt 101 is in close contact with the transfer paper, and is secondarily transferred onto the transfer paper to form a full-color image on the white transfer paper. The transfer paper on which a full-color image is formed in this way exits the secondary transfer nip as the paper transport belt 24 moves endlessly, and is then sent from the paper transport belt 24 to the fixing device 25.

The fixing device 25 includes a belt unit that moves the fixing belt 26 endlessly while being stretched by two rollers, and a pressure roller 27 that is pressed toward one roller of the belt unit. The fixing belt 26 and the pressure roller 27 are in contact with each other to form a fixing nip, and the transfer paper received from the paper transport belt 24 is sandwiched between the fixing nips. Of the two rollers in the belt unit, the roller that is pressed from the pressure roller 27 has a heat source (not shown) inside and pressurizes the fixing belt 26 while heating. The heated and pressurized fixing belt 26 heats the transfer paper sandwiched between the fixing nips. The full color image is fixed on the transfer paper by the influence of the heating and the nip pressure.
In the illustrated example, the transfer paper is disposed below the secondary transfer device 22 and the fixing device 25 in parallel with the image forming unit 20 described above to reversely discharge the transfer paper or to form images on both sides of the transfer paper. And a reversing device 28 for re-feeding and refeeding.

  The transfer paper subjected to the fixing process in the fixing device 25 is stacked on a stack portion 57 provided outside the left side plate in the drawing of the printer housing. Alternatively, the transfer paper on which the fixing process has been performed is sent to the reversing device 28 with the conveying direction being switched by the switching claw 105 in order to form a toner image on the other surface. To return to the secondary transfer nip.

  When a document (not shown) is copied, for example, a bundle of sheet documents is set on the document table 30 of the automatic document feeder 400. However, when the original is a single-sided original that is closed in a main form, it is set on the contact glass 32. Prior to this setting, the automatic document feeder 400 is opened with respect to the copying machine main body, and the contact glass 32 of the scanner 300 is exposed. Thereafter, the single-bound original is pressed by the closed automatic document feeder 400.

  After the original is set in this manner, when the copy start button 38a disposed on the operation display unit 37 shown in FIG. 2 is pressed, the original reading operation by the scanner 300 is started. However, when a sheet document is set on the automatic document feeder 400, the automatic document feeder 400 automatically moves the sheet document to the contact glass 32 prior to the document reading operation. In the document reading operation, first, the first traveling body 33 and the second traveling body 34 start traveling together, and light is emitted from a light source provided in the first traveling body 33. Then, the reflected light from the document surface is reflected by a mirror provided in the second traveling body 34, passes through the imaging lens 35, and then enters the reading sensor 36. The reading sensor 36 produces image information by performing photoelectric conversion based on the incident light.

  In parallel with the document reading operation, the devices and members in the process cartridges 18Y, 18M, 18C, and 18K, the intermediate transfer unit 17, the secondary transfer device 22, and the fixing device 25 start driving. Then, the optical writing unit 21 is driven and controlled based on the image information produced by the reading sensor 36, and the above-described operations of the respective devices and members are performed on the respective photoreceptors 1Y, 1M, 1C, and 1K. A Y toner image, an M toner image, a C toner image, and a K toner image are formed. These toner images become four-color toner images superimposed and transferred on the intermediate transfer belt 101.

Further, almost simultaneously with the start of the document reading operation, the paper feeding operation is started in the paper feeding device 200. In this paper feeding operation, one of the paper feeding rollers 42 is selectively rotated, and the transfer paper is sent out from one of the paper feeding cassettes 44 accommodated in the paper bank 43 in multiple stages. The fed transfer sheets are separated one by one by the separation roller pair 45 and enter the paper feed path 46, and then conveyed toward the secondary transfer nip by the conveyance roller pair 47.
In some cases, paper feeding from the manual feed tray 51 is performed instead of such paper feeding from the paper feeding cassette 44. In this case, after the manual feed roller 50 is selectively rotated to feed the transfer paper on the manual feed tray 51, the separation roller pair 52 separates the transfer paper one by one and enters the manual feed path 53 of the printer unit 100. Feed paper.

  In this copying machine, when a multicolor image composed of two or more colors of toner is formed, the following is performed. That is, the upper transfer surface of the intermediate transfer belt 101 is stretched in a substantially horizontal posture so that all the photoconductors 1Y, 1M, 1C, and 1K are brought into contact with the upper stretch surface, and the corresponding primary transfer bias. The rollers 62Y, 62M, 62C, and 62K are pressed against the back surface of the intermediate transfer belt 101. On the other hand, when forming a monochrome image consisting of only K toner, the intermediate transfer belt 101 is tilted to the lower left in the drawing by a mechanism (not shown), and the upper stretched surface and the primary transfer bias roller. 62Y, 62M, and 62C are separated from the photoreceptors 1Y, 1M, and 1C. Of the four photoconductors 1Y, 1M, 1C, and 1K, only the K photoconductor 1K is rotated counterclockwise in the drawing to form only the K toner image. At this time, for Y, M, and C, the driving of not only the photosensitive member but also the developing device is stopped to prevent unnecessary consumption of the photosensitive member and the developer.

As shown in FIG. 2, the copying machine includes an operation display unit 37 that gives operation instructions to the devices and devices in the copying machine and checks the operation status. The operation display unit 37 includes a copy start button 38a and a numeric keypad 38b and various key buttons and a touch panel type liquid crystal display unit 39. In FIG. 2, reference numeral 58 is opened and closed when the process cartridges 18Y, 18M, 18C, and 18K and a developer storage container, which will be described later, are attached to and detached from the main body of the image forming apparatus, and when various inspections and maintenance are performed. Shows the front door. Further, as shown in FIG. 15 to be described later, the present copying machine includes a control unit 210 including a CPU 211 that controls each of the above devices and devices in the copying machine.
The operator sends a command to the control unit 210 by a key input operation on the operation display unit 37, so that the single-sided print mode, which is a mode for forming an image only on one side of the transfer paper, is selected from three modes. One can be selected. The three single-sided printing modes include a direct discharge mode, a reverse discharge mode, and a reverse decal discharge mode.

With reference to FIG. 3, the developing device 4 and the photoreceptor 1 provided in one of the four process cartridges 18Y, 18M, 18C, and 18K will be described. FIG. 3 is an enlarged configuration diagram illustrating the developing device 4 and the photosensitive member 1 included in one of the four process cartridges 18Y, 18M, 18C, and 18K. The four process cartridges 18Y, 18M, 18C, and 18K have substantially the same configuration except that the colors of the toners to be handled are different. Subscripts are omitted.
As shown in FIG. 3, the surface of the photoreceptor 1 is uniformly charged by a charging device (not shown) while rotating in the direction of arrow G in the drawing. The charged surface of the photosensitive member 1 is supplied with toner from the developing device 4 to the latent image on which an electrostatic latent image is formed by laser light emitted from an exposure device (not shown) to form a toner image.

The developing device 4 has a developing roller 5 as a developer carrying member for supplying toner to the latent image on the surface of the photoreceptor 1 while moving the surface in the direction of arrow I in the drawing. Further, a supply screw 8 is provided as a supply conveyance member that conveys the developer in the depth direction of the sheet of FIG. 3 while supplying the developer to the developing roller 5. The supply screw 8 is a developer transport screw that includes a rotation shaft and a blade provided on the rotation shaft, and transports the developer in the axial direction by rotating in the arrow M direction in the figure.
A developing doctor 12 as a developer regulating member for regulating the developer supplied to the developing roller 5 to a thickness suitable for development is provided on the downstream side of the surface moving direction from the portion facing the supply screw 8 of the developing roller 5. ing.
The developed developer that has passed through the developing section is collected downstream from the developing section, which is the facing portion of the developing roller 5 with respect to the photoconductor 1, and the collected developer is collected in the same direction as the supply screw 8. A recovery screw 6 is provided as a recovery transport member for transporting to the front. A supply conveyance path 9 including a supply screw 8 is provided in the lateral direction of the developing roller 5, and a collection conveyance path 7 including a recovery screw 6 is provided in parallel below the development roller 5 (two or more items are provided side by side). Mean).

The developing device 4 is provided with a stirring conveyance path 10 in parallel with the collection conveyance path 7 below the supply conveyance path 9. The agitating and conveying path 10 includes an agitating screw 11 as an agitating and conveying member that rotates in the direction of arrow C in the figure and conveys the developer to the front side in the figure, which is the opposite direction to the supply screw 8. .
The supply conveyance path 9 and the agitation conveyance path 10 are partitioned by a first partition wall 133 as a partition member. As for the part which partitions the supply conveyance path 9 and the stirring conveyance path 10 of the first partition wall 133, both ends of the front side and the back side in the figure are openings, and the supply conveyance path 9 and the stirring conveyance path 10 are separated from each other. Communicate.
The supply conveyance path 9 and the recovery conveyance path 7 are both partitioned by the first partition wall 133, but an opening is provided at a location where the supply conveyance path 9 and the recovery conveyance path 7 of the first partition wall 133 are partitioned. Absent.
Further, the two conveyance paths of the agitation conveyance path 10 and the collection conveyance path 7 are partitioned by a second partition wall 134 as a partition member. The second partition wall 134 has an opening on the front side in the figure, and the stirring conveyance path 10 and the collection conveyance path 7 communicate with each other.

  The developer thinned by the developing doctor 12 on the developing roller 5 is transported to a developing area which is a portion facing the photosensitive member 1 for development. The developer after development is collected in the collection conveyance path 7 and conveyed to the front side of the cross section in FIG. 3, and to the agitation conveyance path 10 through the opening of the first partition wall 133 provided in the non-image area portion. Developer is transferred.

  In the supply conveyance path 9, when the developer in the supply conveyance path 9 exceeds a predetermined volume, a part of the developer discharge port 94 is discharged to the outside of the developing device 4 and discharged from the developer discharge port 94. And a discharge conveyance path 2 provided with a discharge conveyance screw 2a for conveying the developed developer to the outside of the developing device 4. The discharge conveyance path 2 is disposed on the downstream side in the conveyance direction of the supply conveyance path 9 so as to be adjacent to the supply conveyance path 9 with the partition wall 135 interposed therebetween, and the developer discharge port 94 is connected to the supply conveyance path 9 and the discharge conveyance path 2. Is an opening provided in the partition wall 135 so as to communicate with each other.

A developer containing toner and carrier is supplied to the stirring and conveying path 10 from the replenishment port provided on the upper side of the stirring and conveying path 10 near the opening of the first partition wall 133 on the upstream side of the developer conveying direction in the stirring and conveying path 10. To be replenished. Hereinafter, the developer in which the toner replenished to the developing device 4 and the carrier are mixed is referred to as “premix toner”. In the present embodiment, the toner amount in the premix toner is 25 to 35% by weight, and the toner amount in the developer in the developing device 4 is 4 to 10% by weight.
In this embodiment, toner having an outflow start temperature of 90 ° C. or lower is used. By using toner whose outflow start temperature is 90 ° C. or lower, fixing can be performed at a low temperature, and energy saving and speeding up of the image forming apparatus can be achieved.

With reference to FIG. 4, the arrangement relationship between the developer replenishing device for each color and the developer storage container for each color will be described. FIG. 4 is a perspective view showing the overall configuration of each color developing device 4Y, 4M, 4C, 4K and developer replenishing device 70Y, 70M, 70C, 70K for replenishing the developing device with premixed toner.
The developer supply devices 70Y, 70M, 70C, and 70K are disposed above the developing devices 4Y, 4M, 4C, and 4K. The developer supply device 70 includes a developer storage container 71 that stores premixed toner and a sub hopper 90 (see FIG. 12) described later (in this figure, C and K developer storage containers). 71C and 71K are shown). The developer storage container 71 is held by the container holding unit 77. The container holding portion 77 is divided into four, and the developer storage containers 71 of Y color, M color, C color, and K color are held in order from the left side in the drawing. The developer container 71 is detachably held with respect to the container holding part 77. When the pre-mixed toner in the developer container 71 runs out, the user pulls out the developer container 71 from the container holder 77 and inserts a new developer container 71 into the container holder 77. Accordingly, new premix toner is supplied to a sub hopper 90 (see FIG. 12) described later.

  The developer supply devices 70Y, 70M, 70C, and 70K are disposed on the front side of the image forming apparatus, that is, on the front side of the paper surface in FIG. 1, and on the right front door 58 side in FIG. The developer container 71 can be accessed.

With reference to FIGS. 5 and 6, the developer storage container for K color and the developer storage containers for Y, M, and C colors will be described. FIG. 5 is a perspective view of a developer storage container 71K for K color, and FIG. 6 is a storage of developer for color (Y, M, C) used in a Y, M, C color developer supply device. It is a perspective view of containers 71Y, 71M, 71C.
In this embodiment, as shown in FIG. 5 and FIG. 6, the developer storage container 71K for K color has a larger volume than the developer storage containers 71Y, 71M, 71C for color (Y, M, C). It has become. A typical user is more likely to output a black and white image than a full color image. For this reason, the toner consumption speed is faster for black (for K color) than for color (Y, M, C). Therefore, when the K-color developer storage container 71K has the same shape as the color developer storage containers 71Y, 71M, 71C, the K-color developer storage container 71 is frequently replaced. User convenience deteriorates. For this reason, in this embodiment, the volume of the developer storage container 71K for K color is made larger than the volume of the developer storage containers 71Y, 71M, 71C for color (Y, M, C). More premix toner is stored than the developer storage containers 71Y, 71M, 71C for color (Y, M, C).

FIG. 7 is a cross-sectional view of color developer storage containers 71Y, 71M, 71C.
As shown in FIG. 7, the developer storage containers 71Y, 71M, 71C for color include a container main body 71A as a developer storage section, a transport screw 72 as a supply member installed in the container main body 71A, and an agitation. And an agitator 73 as a member. The agitator 73 is disposed in parallel with the transport screw 72 in the container main body 71A.

  The agitator 73 includes a shaft portion 731, a bone portion 734 as a connection portion molded integrally with the shaft portion 731, and a wing portion 732 attached to the bone portion 734. The wing part 732 is supported by the shaft part 731 via the bone part 734. The agitator 73 is driven by a developer supply driving unit 80 (see FIGS. 10 and 11) described later, and rotates integrally with a shaft portion 731 disposed in parallel with the conveying screw 72. Then, the premix toner in the container main body 71A is transported so as to be moved toward the transport screw 72 while stirring. The shaft portion 731 and the bone portion 734 of the agitator 73 are formed as rigid bodies having rigidity. Further, since the wing portion 732 of the agitator 73 is flexible, the agitator 73 rotates while the wing portion 732 is bent by the wing portion 732 coming into contact with the inner wall of the container main body 71A.

  The shaft portion 731 and the bone portion 734, which are rigid bodies of the agitator 73, are simply and preferably formed integrally with metal or the like, but other materials or manufacturing methods may be used. In addition, the flexible wing portion 732 is preferably manufactured from a material having low rigidity. For example, the wing portion 732 is desirably a sheet-like flexible material made of PET (polyethylene terephthalate), PE (polyethylene), PP (polypropylene), PPS (polyphenylene sulfide), or the like. The thickness of the wing portion 732 is preferably about 50 [μm] to about 500 [μm], more preferably 100 [μm] to 300 [μm].

  As described above, the agitator 73 is composed of the shaft portion 731, the bone portion 734, and the wing portion 732 as separate members. May be.

FIG. 8 is a cross-sectional perspective view of a developer storage container 71K for K color.
A first agitator 73a, a second agitator 73b, and a transport screw 72 are installed in the container main body 71A of the developer storage container 71K for K color. The first agitator 73a and the second agitator 73b have the same configuration as the agitator 73 provided in the color developer storage containers 71Y, 71M, 71C shown in FIG.

FIG. 9 is an enlarged view showing the vicinity of the coupling 74a, 74b attachment portion of the K developer storage container 71K.
As shown in FIG. 9, one ends of the shaft portions 731a and 731b of the first and second agitators 73a and 73b of the developer storage container 71K for K are exposed from the container body 71A, and a coupling 74a is connected to the one end. , 74b. Further, as shown in FIG. 6, one end of the shaft portion 731 of the agitator 73 of the color developer storage containers 71Y, 71M, 71C is also exposed from the container body 71A, and a coupling 74 is provided at one end thereof. Is provided.

The developer supply driving unit will be described with reference to FIGS. 10 and 11. FIG. 10 is a simplified perspective view showing the developer supply driving units 80Y, 80M, 80C, and 80K, and FIG. 11 is a simplified front view of the developer supply drive units 80Y, 80M, 80C, and 80K. .
The developer supply driving units 80Y, 80M, 80C, and 80K supply the premixed toner in the developer storage container 71 to the sub hoppers 90Y, 90M, 90C, and 90K of the developer supply device shown in FIGS. It is a drive part used sometimes. The developer supply driving units 80Y, 80M, 80C, and 80K include an agitator 73 of the developer container 71, a conveying screw 72, and first and second agitating and conveying members 96 in sub-hoppers 90Y, 90M, 90C, and 90K, which will be described later. 97 (see FIG. 13) is driven.

As shown in FIGS. 10 and 11, each developer supply drive unit 80Y, 80M, 80C, 80K includes a supply drive motor 81Y, 81M, 81C, 81K as a drive source. In the present embodiment, the supply drive motors 81Y, 81M, 81C, and 81K employ DC motors that are DC motors. Each developer supply drive unit 80Y, 80M, 80C, 80K has a gear train composed of a plurality of gears. The gears constituting this gear train are rotatably supported by face plates 86Y, 86M, 86C, 86K shown in FIG. Further, each of the developer supply driving units 80Y, 80M, 80C, 80K is provided with transport joints 83Y, 83M, 83C, 83K connected to the transport screws 72 of the developer storage containers 71Y, 71M, 71C, 71K. Yes.
The color developer supply drive units 80Y, 80M, and 80C are provided with drive side couplings 85Y, 85M, and 85C connected to the coupling 74 described above. The K-color developer supply drive unit 80K is provided with a first drive side coupling 85aK connected to a coupling 74a attached to the shaft portion 731a of the first agitator. Further, a second drive side coupling 85bK connected to the coupling 74b attached to the shaft portion 731b of the second agitator is also provided.

The driving force of each of the supply drive motors 81Y, 81M, 81C, 81K is transmitted to the transport screw 72 in the developer storage container of each color via the worm gear, the plurality of gears, and the transport joints 83Y, 83M, 83C, 83K. Then, the conveying screw 72 is driven to rotate. Further, the supply drive motors 81Y, 81M, 81C, and 81K are supplied to the agitator drive gears 84Y, 84M, and 84C and the first agitator drive gear 84aK through a plurality of gears from the transfer joints 83Y, 83M, 83C, and 83K. The driving force is transmitted. Then, the driving force is transmitted to the agitator 73 via the drive side couplings 85Y, 85M, 85C provided coaxially with the agitator drive gears 84Y, 84M, 84C, and the agitator 73 is rotationally driven. Further, the driving force is transmitted to the first agitator 73a via the first drive side coupling 85aK provided coaxially with the first agitator drive gear 84aK, and the first agitator 73a is rotationally driven.
Regarding the K-color developer supply drive unit 80K, the drive force of the supply drive motor 81K is transmitted from the first agitator drive gear 84aK to the second agitator drive gear 84bK. Then, the driving force is transmitted to the second agitator 73b via the second driving side coupling 85bK provided coaxially with the second agitator driving gear 84bK, and the second agitator 73b is rotationally driven.

  Further, the driving force of each of the supply drive motors 81Y, 81M, 81C, 81K is applied to the supply-side one-way clutch 82 attached to the rear end portion of the rotary shaft of the first agitating and conveying member 96 (see FIG. 13) described later. Communicated. Then, the driving force of each of the supply drive motors 81Y, 81M, 81C, 81K is transmitted to the first stirring / conveying member 96 and the second stirring / conveying member 97, which will be described later, via the supply-side one-way clutch 82.

  The sub hoppers 90Y, 90M, 90C, and 90K of the developer supply devices 70Y, 70M, 70C, and 70K will be described with reference to FIGS. Since the sub-hoppers 90Y, 90M, 90C, and 90K for each color are the same, the K-color sub-hopper will be described here, and the subscripts Y, M, C, and K are omitted as appropriate in the following description. explain. 12 is a perspective view showing the configuration of the sub hopper 90, and FIG. 13 is a perspective view showing the internal structure of the sub hopper 90. As shown in FIG.

  As shown in FIGS. 12 and 13, the sub hopper 90 includes a case 93 b that houses the first agitating and conveying member 96, the second agitating and conveying member 97, the first conveying member 98, and the second conveying member 99, and has an upper opening. An upper cover 93a is provided to close the opening of the case 93b. The upper cover 93 a is formed with a receiving port 91 that receives premix toner supplied from the supply port of the developer container 71.

  In the present embodiment, a sub hopper 90 is provided directly above the developing device 4, and the sizes of the sub hoppers 90 for the respective colors are the same. On the other hand, as described above with reference to FIGS. 5 and 6, the developer storage container 71 disposed immediately above the sub hopper 90 is not the same for each color, and the K-color development storage container 71K is used for color. It is larger than the developer storage containers 71Y, 71M, 71C. For this reason, the positions of the supply ports 72aY, 72aM, 72aC, and 72aK for supplying the premix toner in the developer storage container 71 to the developer storage section 90a are different due to the layout of the apparatus as shown in FIG. . In the present embodiment, the distance from the supply port 72a and the wall surface on which the sub-hopper developer detection sensor 95 is provided is about 4 mm for K color, about 13 mm for C color, about 23 mm for M color, and about 23 mm for Y color. 33 mm.

  When the receiving port 91 of the sub hopper 90 is provided with the positions of the supply ports 72aY, 72aM, 72aC, 72aK of the developer storage containers 71, it is necessary to provide the upper cover 93a for each color, which increases the number of parts. This leads to an increase in the cost of the device. For this reason, in the present embodiment, the receiving port 91 of the upper cover 93a has a rectangular shape extending in the direction in which the developer storage containers 71 are arranged. As a result, even if the positional relationship between the sub hopper 90 and the supply ports 72aY, 72aM, 72aC, 72aK of the developer container 71 is different from each other in the arrangement direction of the developer container 71, the common upper cover Can respond. Thereby, based on the positional relationship between the sub hopper 90 and the supply port of the developer container 71, the number of parts can be reduced and the apparatus can be made cheaper than when the upper cover 93a is prepared for each color. Can do.

  As shown in FIG. 14, the sub hopper 90 develops the developer storage unit 90a that temporarily stores the premix toner supplied from the developer storage container 71 and the premix toner stored in the developer storage unit 90a. And a transport unit 90 b that transports the apparatus 4. The developer storage unit 90 a and the transport unit 90 b are formed by partitioning the inside of the case with a partition wall 92. As shown in FIG. 13, a first opening 92a is formed on the rear side of the partition wall 92, which is the developer supply driving unit side, and a second opening 92b is formed on the front side opposite to the rear side.

As shown in FIG. 13, a first agitating and agitating member 96 and a second agitating and conveying member 97 are arranged side by side in the developer storage section 90a. Further, a developer detection sensor 95 as a developer detection means for detecting the presence or absence of the developer in the developer reservoir is provided on the right side wall of the case 93b in the drawing. The developer detection sensor 95 is, for example, a piezoelectric sensor, and the developer detection unit is disposed at a predetermined height from the bottom of the case.
The first stirring / conveying member 96 disposed on the right side of the developer storage unit 90a in the drawing has a rotating shaft 96c and a helical screw 96b having a large pitch. Further, a cleaning member 96 a for cleaning the developer detecting portion of the developer detecting sensor 95 is provided at a location facing the developer detecting portion of the developer detecting sensor 95 of the first stirring and conveying member 96. Further, a paddle 96 d for delivering premix toner to the second agitating and conveying member 97 is provided in the vicinity of a location facing the receiving port 91 of the developer storage container.

  The second stirring / conveying member 97 disposed on the partition wall 92 side of the developer storage unit 90a is provided with a spiral screw 97b having a large pitch and a paddle 97a on a rotating shaft 97c. A paddle 96a is provided in a portion of the rotating shaft 97c facing the first opening 92a and a portion facing the second opening 92b. Further, the rear side of the portion of the screw 97b facing the receiving port 91 is shaped so that the premix toner is conveyed to the rear side, and the front side of the portion facing the receiving port 91 is pre-pressed. The shape is such that the mixed toner is conveyed to the front side.

  The transport unit 90b is partitioned into a first transport path 902A and a second transport path 902B by a transport partition wall 901. A transfer opening 901a is formed on the front side of the transfer partition wall 901, and the first transfer path 902A and the second transfer path 902B are communicated with each other. A first transport member 98 is disposed in the first transport path 902A, and a second transport member 99 is disposed in the second transport path 902B. Each conveying member 98, 99 is composed of rotating shafts 98b, 99b and helical screws 98a, 99a. As for the screw 98a of the 1st conveyance member 98, the pitch of the location facing the opening 901a for conveyance is narrower than the other location. The screws 99a of the second conveying member 99 have a constant pitch in the rotation axis direction. The first transport member 98 transports the premix toner in the first transport path 902A toward the transport opening 901a (from the rear side to the front side), and the second transport member 99 pre-loads in the second transport path 902B. The mixed toner is conveyed from the front side to the rear side. A developer replenishment outlet communicating with a replenishment port (not shown) of the developing device 4 is provided at a position located at the developer conveyance downstream end of the second conveyance path 902B on the bottom surface of the case 93b. The premix toner that has been transported through the second transport path 902B by the second transport member 99 is supplied to the developing device 4 from the developer supply outlet.

  Further, the sub hopper 90 is provided with a developer replenishment drive unit 110 used when replenishing the developing device 4 with premix toner. The developer replenishment drive unit 110 is provided on the front side of the sub hopper 90, and includes a replenishment drive motor 111 including a stepping motor and a gear train including a plurality of gears. The driving force of the replenishment drive motor 111 is transmitted to the first agitation transport member 96 via the replenishment-side one-way clutch 112 provided at the other end (lower end in the figure) of the rotation shaft 96c of the first agitation transport member 96. The first stirring and conveying member 96 is driven to rotate. Further, the driving force of the replenishment drive motor 111 is transmitted from the first stirring / conveying member 96 to the second stirring / conveying member 97 via a plurality of gears, and the second stirring / conveying member 97 is rotationally driven. In addition, a driving force is transmitted from the replenishment drive motor 111 to the first and second transport members 98 and 99 through a plurality of gears, and the first and second transport members 98 and 99 are rotationally driven.

  The premix toner in the developer storage unit 90a is sequentially transferred from the first opening 92a and the second opening 92b to the transport unit 90b, so that the amount of premix toner in the developer storage unit 90a decreases. . As a result, the height of the premix toner is lower than the developer detection portion of the developer detection sensor 95, and the developer detection sensor 95 does not detect the premix toner. Then, the supply drive motor 81 is driven to start supplying the premix toner to the developer storage unit 90a.

In the present embodiment, a developer storage unit 90a is provided, and the premix toner is stored in the developer storage unit 90a. As a result, even if the developer container 71 becomes empty, the toner can be supplied to the developing device 4 for a while with the premix toner stored in the developer storage section 90a. As a result, a good image can be formed while the user prepares a new developer container.
Note that the detailed configuration and operation (movement of the premix toner) in the sub hopper 90 other than those described above are beyond the scope of the disclosure of the present invention, and thus further detailed description is omitted.

  FIG. 15 is a block diagram showing an example of a main configuration of the main control system of the present invention. In FIG. 15, the control unit 210 has a function as a determination unit and a control unit of the present invention. The control unit 210 includes a CPU 211, a ROM 212, a RAM 213, a timer (not shown), and the like inside, and a microcomputer having a configuration in which these are connected by a signal bus (not shown). The CPU 211 of the control unit 210 mainly functions as the above-described determination means and control means. The control unit 210 is provided in a control board arrangement unit in the image forming apparatus main body.

The CPU 211 is based on various signals shown in the figure based on various signals from the operation display unit 37, front door opening / closing sensor 59, developer detection sensor 95, detection signal from the toner concentration sensor 201, and the like, and an operation program called from the ROM 212. The controlled object driving means is controlled. The ROM 212 stores an operation program and necessary related data according to flowcharts shown in FIGS. 16 and 17 described later, and the operation program and related data are appropriately called by the CPU 211. The RAM 213 has a function of temporarily storing calculation results of the CPU 211 and a function of storing data keys and on / off signals input from various keys on the operation display unit 37 and the various sensors as needed. doing.
The CPU 211 and the RAM 213 have a function of a counting unit that counts the number of times of load detection. However, this counting unit may be provided separately from the configuration of the control unit 210.

  The control target drive means includes a liquid crystal display section of the operation display section 37, supply drive motors 81Y, 81M, 81C, 81K, a solenoid 60 of a front door lock mechanism (not shown), a printer section drive section 115 including a power source, and the like. . Each of the supply drive motors 81Y, 81M, 81C, 81K receives a command signal from the CPU 211 via the corresponding motor driver 88Y, 88M, 88C, 88K, and outputs an output signal such as a current value described later to the CPU 211. Send to. Since the control contents for the supply drive motors 81Y, 81M, 81C, 81K and the output signal contents from the motor drivers 88Y, 88M, 88C, 88K are the same for each color, in the following description, Y, M , C, K will be omitted as appropriate.

Specifically, the control unit 210 (particularly the CPU 211) has functions of the following determination means and control means.
First, the controller 210 detects that the load applied to the drive motor 81 for supply exceeds the predetermined number of times when the voltage detection element of the motor driver 88 detects that the load is greater than a certain value. Has a function of determining that the supply drive motor 81 is abnormal.
Secondly, when the control unit 210 determines that the drive source such as the supply drive motor 81 is abnormal, the control unit 210 indicates that the supply drive motor 81 is abnormal by using the liquid crystal display unit 39 of the operation display unit 37. It has a function to notify.

Third, the control unit 210 has a function of performing operation stop control of the image forming apparatus (the printer unit driving unit 115 including the power source) when an abnormality of the supply driving motor 81 is determined.
Fourth, the control unit 210 (particularly counting means such as the CPU 211 and the RAM 213) is counted by the counting means when it is determined that the developer supplied from the developer storage container 71 has been supplied. Has a function to clear the number of times of abnormality detection.

Fifth, the control unit 210 generates an output signal from the developer detection sensor 95 (a signal detected that the developer supplied from the developer storage container 71 is present in the developer storage unit 90a of the sub hopper 90). And a function of recognizing that the developer has been replenished.
Sixth, the control unit 210 has a function of updating the operation for determining that the supply drive motor 81 is abnormal when the developer container 71 is replaced.

  Hereinafter, the number of times of load detection is also referred to as the number of times of abnormality detection. Further, as a load detection means for detecting a load applied to the supply drive motor 81, a current value flowing through the supply drive motor 81 is detected using a voltage detection element provided in the motor driver 88. The voltage detection element converts a voltage value applied to the supply drive motor 81 into a current value.

  The control unit 210 determines that the motor load is equal to or greater than a certain value when the current flowing through the supply drive motor 81 is equal to or greater than a predetermined value. An example of the predetermined current value is as follows. That is, in this copying machine, the current flowing through the supply drive motor 81 is set to 500 mA as a predetermined value (hereinafter also referred to as a set current value). As a method for setting the current value, there is 220 mA as the rated current value set by each supply drive motor 81. Similarly, there is 720 mA as a current value that is regarded as a limit. A predetermined value is appropriately determined based on an empirically grasped data value or a test or the like in advance between values larger than the rated current and lower than the limit current value. The reason why the limit current value is not set is as follows. If the limit is not reached, an abnormality determination is not made. However, although the supply drive motor 81 is locked / failed, there is a region where the abnormality is not determined. This is because the life of the drive motor 81 is reduced.

  In the present invention, the drive torque may be considered as a load detection means for detecting the load applied to the drive source. However, since a special device is required for measuring the drive torque, it is not adopted in terms of cost and labor. Yes. The reason for not using the voltage as a reference is that the rated value is determined by the current value as the specification of the supply drive motor 81 as will be described later, and therefore it is necessary to use the current reference.

  Although there is no special rule for setting the number of times related to the number of times of load detection (number of times of abnormality detection), the number of times is set too small, not too much as appropriate, considering data accumulated empirically. Therefore, the number of times of abnormality detection can be arbitrarily set by using a programmable PROM or setting a service program for a service person.

  Here, the front door opening / closing sensor 59, the front door lock mechanism solenoid 60, and the printer unit drive unit 115 including the power supply, which have not been described above, will be supplementarily described. The front door open / close sensor 59 is a sensor that detects the open / closed state of the front door 58 shown in FIG. 2. For example, the front door open / close sensor 59 is provided on a normal switch or a transmissive optical sensor and the front door 58 and blocks the optical path of the optical sensor. A combination with a light shielding plate is used. The front door lock mechanism includes a locked member provided at an appropriate portion of the front door 58 shown in FIG. 2 and a lock portion provided on the image forming apparatus main body side and selectively engageable with the locked member. A combination with the solenoid 60 provided is used. More specific examples are substantially the same as those disclosed in FIGS. 8 and 9 of Japanese Patent No. 4469163. A printer unit driving unit 115 including a power source collectively represents the entire driving unit of each of the above-described devices including the printer unit of the image forming apparatus that operates by supplying power.

In addition to the first to sixth functions described above, the control unit 210 also has the following functions. That is, when the control unit 210 detects that the premix toner in the developer storage unit 90a is less than a predetermined amount based on an output signal from the developer detection sensor 95, the control unit 210 drives the supply motor 81 to supply the premix toner. Supply toner. When the control unit 210 detects that the premix toner in the developer storage unit 90a is equal to or greater than a predetermined amount based on an output signal from the developer detection sensor 95, the control unit 210 stops driving the supply drive motor 81 and performs pre-processing. The supply of mixed toner is terminated.
If the output signal from the developer detection sensor 95 does not change even after the supply drive motor 81 is driven for a predetermined time (12 seconds in this embodiment), the control unit 210 supplies the supply drive motor. The driving of 81 is stopped. Then, assuming that there is no premix toner in the developer container, a message is displayed on the liquid crystal display unit 39 of the operation display unit 37 of the main body of the image forming apparatus prompting the developer container 71 to be replaced.

  Note that the control unit 210 receives a toner density detection result from a toner density sensor 201 that is a magnetic permeability sensor, for example, as a toner density detection unit that detects the toner density of the developer in the developing device 4. The control unit 210 compares the target value stored in the RAM 213 backed up by a battery or the like with the detection result of the toner density sensor 201, and supplies the replenishment drive so that an amount of premix toner corresponding to the comparison result is replenished. The motor 111 (not shown in FIG. 15) is controlled. Specifically, the replenishment drive motor 111 is driven for a time corresponding to the replenishment amount. As a result, an appropriate amount of premix toner is supplied from the developer replenishing device 70 to the developer whose toner concentration has decreased due to toner consumption associated with development. As described above, the premix toner has a toner amount of 25 to 35% by weight, which is larger than the toner amount (4 to 10% by weight) of the developer in the developing device. Therefore, by supplying the premix toner into the developing device, the toner concentration of the developer in the developing device increases, and the toner concentration of the developer in the developing device 4 is maintained near the target value.

  The reason why the DC motor is used as the supply drive motor 81 is as follows. That is, since the agitating and conveying members 96 and 97, the conveying screw 72, and the agitator 73 are rotationally driven in the supply drive motor 81, the torque applied to the supply drive motor 81 is large. Further, since the drive is performed also during the developer replenishing operation, the burden is increased as compared with the case of driving only during the supply of the developer. Since the supply amount supplied to the developer storage unit may be rougher than the supply amount supplied to the developing device 4, a DC motor that is less expensive than the stepping motor is used for the supply drive motor 81. Yes.

Next, with reference to the flowcharts of FIG. 16 and FIG. 17, an operation flow of abnormal current detection according to the supply drive motor 81 of the present embodiment will be described. FIG. 16 is a flowchart showing the operation sequence of motor abnormal current detection according to an embodiment, and FIG. 17 is a flowchart following FIG. 16 and 17, it is noted that the developer container 71 is simply referred to as “container”, and the supply drive motor 81 is simply referred to as “motor”. It goes without saying that this operation flow is applied to the supply motor 81 for each color.
First, in step S1, an operation of detecting an abnormal current flowing through the supply drive motor 81 is started. Next, in step S2, it is checked whether or not developer replenishment (supply) is necessary. Whether or not developer replenishment (supply) is necessary is determined by the control unit 210 based on an output signal from the developer detection sensor 95 whether or not the premix toner in the developer storage unit 90a is less than a predetermined amount. It is done by doing. When the control unit 210 determines that the premix toner in the developer storage unit 90a is less than a predetermined amount, the control unit 210 drives the supply drive motor 81 to start the operation of supplying and supplying the premix toner. Specifically, the premix toner is replenished and supplied into the developer storage section 90a by the developer stirring operation by the agitator 73 in the developer storage container 71 and the supply operation by the conveying screw 72 (step S3).
In step S2, when it is not necessary to supply (supply) the developer, the process returns to step S1.

  After starting the developer stirring operation in the developer container 71 in step S3, it is checked whether or not the value of the current flowing through the supply drive motor 81 exceeds the set current value (500 mA described above). That is, motor current value> set current value? Therefore, it is possible to compare whether or not the current value (data signal: motor current value) transmitted through the voltage detection element in the motor driver 88 of the supply drive motor 81 exceeds the set current value (500 mA described above). Done. When the motor current value exceeds the set current value (500 mA described above), a message is displayed on the liquid crystal display unit 39 of the operation display unit 37. As a display example at this time, a warning message such as “Replenishment from the developer container (toner bottle) is not successful. Shake the developer container.” Is displayed (step S5).

  After displaying the message in step S5, the process proceeds to step S6, where the CPU 211 increments the abnormality detection number counter by 1 and stores it in the RAM 213. Next, in step S7, it is checked whether or not the front door 58 of FIG. 2 has been opened. Here, first, the solenoid 60 of the front door lock mechanism is turned on so that the front door 58 can be opened. Next, the user swings the removed developer storage container 71 in accordance with the message display content of the liquid crystal display unit 39, and resets the developer storage container 71 to a predetermined location of the sub hopper 90 (step S8). Next, in step S9, it is checked whether or not the front door 58 of FIG. 2 is closed. Here, immediately after the front door 58 is closed by the user, the solenoid 60 of the front door lock mechanism is turned off, and the front door 58 is locked so that the front door 58 cannot be opened by the user's opening operation.

  Next, the process proceeds to step S10 in FIG. 17 to start the recovery operation. In other words, the normal supply driving motor 81 is driven to replenish and supply the premixed toner into the developer storage section 90a by the developer stirring operation and the supply operation in the developer storage container 71. After the drive of the supply drive motor 81 is started, whether or not the current value flowing through the supply drive motor 81 again exceeds the set current value (500 mA described above) in step S11, that is, is the motor current value> the set current value again? Check. Then, if the motor current value exceeds yes to the set current value (500 mA described above), the process proceeds to step S12.

  In step S12, it is checked whether or not the number of times of abnormality detection has exceeded a preset number of times of five. When the number of times of abnormality detection exceeds 5 times the set number of times, the CPU 211 transmits an abnormality notification signal (service call) to the liquid crystal drive unit in the liquid crystal display unit 39 of the operation display unit 37. Thus, a predetermined message is displayed on the liquid crystal display unit 39 in order to notify that the motor is truly locked / abnormal (failure, breakage, etc.). As an example of display at this time, in order to indicate that the service has failed to be handled by a general user as a service call display, it is necessary to provide a service because repairs are necessary due to a motor abnormality (failure / damage). Please contact me "is displayed (step S13). Next, the CPU 211 forcibly turns off the power to clear the operation of the image forming apparatus and clears the abnormality detection counter to 0 (step S14). Thereafter, the process returns to step S1 and the above-described series of operations is repeated.

  Number of abnormal detections in step S12> 5 times? If the number of abnormality detections does not exceed the set number of times 5, the process returns to step S5, and a message display / warning is displayed on the liquid crystal display unit 39 of the operation display unit 37. Next, in step S6, the abnormality detection number counter is incremented by 1, and the operations in step S7 and subsequent steps are repeated.

  On the other hand, is the motor current value in step S4 and step S11> set current value? When the value of the current flowing through the supply drive motor 81 does not exceed the set current value, the abnormality detection counter is cleared to 0 with the presence of developer by the developer detection sensor 95 as a trigger. That is, at this time, the above-described fourth and fifth functions of the control unit 210 recognize that the developer has been replenished based on the output signal from the developer detection sensor 95 and also detect the abnormality detection frequency counter. Is cleared. The output signal from the developer detection sensor 95 means a signal detected that the developer supplied from the developer storage container 71 exists in the developer storage portion 90a of the sub hopper 90.

  Although not explicitly shown in the flow of FIGS. 16 and 17, for example, after the operation of step S <b> 14 or the like, or when a message is displayed on the liquid crystal display unit 39 to prompt the replacement of the developer storage container 71, The developer container 71 is replaced with a new one. In this case, the operation of determining that the supply drive motor 81 is abnormal is updated by the function of the sixth control unit 210 described above, and the operation from step S1 in FIG. 16 is started.

  In the flow of FIG. 16 and FIG. 17, the operation order of step S5 and step S6 and the operation of step S13 and step S14 are executed simultaneously, so the order of these operations may be reversed.

As described above, according to the present embodiment, the following effects can be obtained.
First, when the load on the motor increases due to toner adhering to the developer container even though the supply drive motor is not abnormal, the operation of the image forming apparatus is suddenly stopped. It is suppressed that the user (user) has to cancel it. That is, there is a basic effect that the supply drive motor is not immediately determined to be abnormal, and there is no trouble in taking the procedure for canceling the abnormality.

  Secondly, since the message content corresponding to the number of times of abnormality detection due to load abnormality of the supply drive motor is notified, it is possible to appropriately grasp that the user has to cancel it according to the message content. When the number of times of abnormality detection due to load abnormality of the supply drive motor reaches a preset number of times 5, it is determined that the motor is truly locked / abnormal, a service call is displayed, and the image forming apparatus is stopped. To control. As a result, appropriate measures including motor replacement can be performed by inspecting the device by a service person.

What has been described above is an example, and the present invention has a specific effect for each of the following aspects.
[Aspect 1]
A developer storage container such as a developer storage container 71 having a developer storage section such as a container main body 71A for storing the developer and a stirring member such as an agitator 73 for stirring the developer in the developer storage section; An image forming apparatus including a drive source such as a supply drive motor 81 that drives a member and a load detection unit such as a voltage detection element of a motor driver 88 that detects a load applied to the drive source. A determination unit such as a control unit 210 that determines abnormality of the drive source based on the detection result is provided, and the determination unit detects the number of times of load detection when the load detection unit detects that the load applied to the drive source is a certain level or more. However, when the preset number of times is exceeded, it is determined that the drive source is abnormal.
According to the aspect 1, as described in the embodiment, when the developer in the developer storage container is stirred by the drive source, when the load is applied to the drive source due to toner fixation or the like, the drive source is immediately There is no effect that it is determined that there is an abnormality, and there is an effect that there is no trouble in taking the procedure for canceling the abnormality.

[Aspect 2]
In the first aspect, a notification unit such as a liquid crystal display unit 39 that notifies the information of the image forming apparatus is provided, and when the number of times of load detection is smaller than the set number, the notification unit is in the developer storage container such as the developer storage container 71 When the developer such as the controller 210 determines that the drive source such as the supply drive motor 81 is abnormal, the controller 210 notifies the developer that the drive source is abnormal. Let me know.
According to the aspect 2, as described in the embodiment, since the abnormal state of the developer in the developer storage container can be known, the developer storage can be performed without immediately determining that the drive source is abnormal. The container can be restored to an appropriate state at an appropriate time.

[Aspect 3]
In the first or second aspect, when it is determined that a drive source such as the supply drive motor 81 is abnormal, the operation stop control is performed on the image forming apparatus (the printer unit drive unit 115 including the power source).
According to the aspect 3, as described in the embodiment, it is determined that the drive source is truly abnormal (motor lock / failure), and the process of putting the image forming apparatus in the operation stop state can be accurately performed at an appropriate time. it can.

[Aspect 4]
In any one of the first to third aspects, the CPU 211 and the RAM 213 that count the number of times of load detection are provided, and the number of times counted by the counting means is a developer storage container such as the developer storage container 71. Cleared when it is determined that the developer supplied from is supplied.
According to Aspect 4, as described in the embodiment, any one of [Aspect 1] to [Aspect 3] can be reliably determined or controlled.

[Aspect 5]
In aspect 4, a developer storage section such as the developer storage section 90a of the sub hopper 90 that temporarily stores the developer supplied from the developer storage container such as the developer storage container 71 is provided, and the developer is replenished. That is, it is detected that the developer supplied from the developer container is present in the developer storage section.
According to the aspect 5, as described in the embodiment, since the developer can be temporarily stored in the developer storage section, it is possible to suppress a problem that the developer is quickly lost.

[Aspect 6]
In any one of the first to fifth aspects, the drive source is an electric motor such as the supply drive motor 81, and the load detection unit detects a current value flowing through the electric motor as a load applied to the drive source. It is means, such as a voltage detection element.
According to the aspect 6, as described in the embodiment, the drive source and the load detection unit can be realized with the simplest configuration, contributing to the effect of the aspect 1, and reducing the cost accordingly.

[Aspect 7]
In any one of the first to sixth aspects, the developer storage container such as the developer storage container 71 is configured to be detachable from the image forming apparatus main body, and when the developer storage container is replaced, The operation for judging the abnormality of the drive source by the judging means such as the control unit 210 is updated.
According to the aspect 7, as described in the embodiment, even when the developer storage container is replaced, the operation of determining the abnormality of the drive source by the determination unit can be continuously performed.

  Although the present invention has been described with respect to specific embodiments, the technical contents disclosed by the present invention are not limited to those exemplified in the above-described embodiments. That is, it may be configured by appropriately combining them, and it will be apparent to those skilled in the art that various embodiments, modifications, and examples can be configured within the scope of the present invention according to the necessity and application. It is.

The load detection means is not limited to detecting the current value via the voltage detection element of the motor driver 88 for each color described above, but an ammeter for measuring the current flowing in the supply motor 81 for each color is used for supplying each color. The drive motor 81 may be provided individually.
The notification means is not limited to visual observation by the liquid crystal display unit 39 or the like, but also includes a buzzer sound and warning notification by voice or the like, and these may be used in combination.
The present invention is not limited to an image forming apparatus that forms an image using a two-component developer including a toner and a carrier as described above, and is an image forming apparatus that forms an image using a toner as a one-component developer. Is also applicable.

  In the above embodiment, as illustrated in FIG. 4, the developer storage containers 71 of the respective colors are described as being configured to be detachable from the container holding portion 77 of the developer supply device 70 of the corresponding process cartridge 18. However, it may be configured to be detachable from the main body of the image forming apparatus. That is, according to the present invention, in the image forming apparatus in which the developing device is configured to be non-detachable from the image forming apparatus main body, the developer storage container is configured to be removable or non-detachable so as to supply the developer to the developing device. The present invention is also applicable to image forming apparatuses that have been used.

1 Photoconductor (an example of a latent image carrier)
4. Developing device (an example of developing means)
18 Process cartridge 21 Optical writing unit 37 Operation display unit 39 Liquid crystal display unit (an example of notification means)
70 Developer Supply Device 71 Developer Storage Container 71A Container Body (Example of Developer Storage Unit)
72 Conveying screw 73 Agitator (an example of a stirring member)
73a First agitator (an example of a stirring member)
73b Second agitator (an example of a stirring member)
74 Coupling 77 Container holding part 80 Developer supply driving part 81 Supply drive motor (an example of drive source)
88 motor driver 90 sub hopper 90a developer storage unit 90b transport unit 95 developer detection sensor (an example of developer detection means)
96 1st stirring conveyance member 97 2nd stirring conveyance member 98 1st conveyance member 99 2nd conveyance member 110 Developer supply drive part 111 Replenishment drive motor 115 Printer part drive part 210 Control part (an example of a determination means and a control means)
211 CPU (an example of determination means and control means)

JP 2012-198382 A

Claims (7)

A developer container having a developer container for storing the developer, and a stirring member for stirring the developer in the developer container;
A drive source for driving the stirring member;
Load detecting means for detecting a load applied to the drive source;
In an image forming apparatus comprising:
A determination unit that determines an abnormality of the drive source based on a detection result of the load detection unit;
The determination means determines whether the drive source is in a state where the number of times of load detection when the load applied to the drive source is detected by the load detection means to be a certain value or more exceeds a preset number of times. An image forming apparatus characterized in that it is determined to be abnormal. An informing means for informing information of the image forming apparatus;
When the number of times of load detection is less than the set number of times, the notification means notifies the abnormal state of the developer in the developer storage container,
The image forming apparatus according to claim 1, wherein when the determination unit determines that the drive source is abnormal, the notification unit causes the notification unit to notify that the drive source is abnormal.   3. The image forming apparatus according to claim 1, wherein when the abnormality of the driving source is determined, operation stop control of the image forming apparatus is performed. Comprising a counting means for counting the number of times of load detection;
4. The number of times counted by the counting means is cleared when it is determined that the developer supplied from the developer storage container has been replenished. The image forming apparatus described in 1. A developer storage unit for temporarily storing the developer supplied from the developer storage container;
5. The image forming according to claim 4, wherein the developer replenishment is a detection that the developer supplied from the developer storage container is present in the developer storage section. apparatus. The drive source is an electric motor,
The image forming apparatus according to claim 1, wherein the load detection unit is a unit that detects a value of a current flowing through the electric motor as a load applied to the drive source. The developer storage container is configured to be detachable from the image forming apparatus main body,
7. The image forming apparatus according to claim 1, wherein when the developer storage container is replaced, an operation for determining abnormality of the drive source by the determination unit is updated.

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