JP5513995B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus that collects a residual developer generated in image formation and a patch image generated by image quality adjustment processing as a waste developer in a waste developer container.

  In the image forming apparatus, it is well known that the developer remains on the photosensitive member when transferring from the photosensitive member to the intermediate transfer member in the transfer step in image formation. Similarly, residual developer is generated on the intermediate transfer member in the secondary transfer step of transferring the developer image on the intermediate transfer member to the recording paper.

  Therefore, the image forming apparatus is provided with a cleaning device for collecting the residual developer remaining on the photosensitive member and the intermediate transfer member in each of the primary and secondary transfer processes, and the residual developer cleaned by the cleaning device. Is provided as a waste developer.

  By the way, in the image forming apparatus, characteristics such as the sensitivity of the photosensitive member and the transfer efficiency of the developer change depending on the use state of each process unit and the surrounding environment. When these characteristics change, the density of the formed image fluctuates, causing a reduction in image quality. In order to prevent such deterioration in image quality, adjustment parameters (grid bias, exposure amount, development bias, transfer bias, etc.) of each part of the image forming unit are adjusted in accordance with predetermined conditions to always obtain good image quality. It is necessary to adjust the image quality so that In the image quality adjustment, a test density patch image (tone pattern) is formed on the intermediate transfer member at a predetermined timing, the test density patch image is measured by a density detector, and the above-described values are used based on the measured values. This is done by adjusting the adjustment parameters. Toner that is a developer for forming a test density patch image is not transferred onto a sheet but is collected as it is by a cleaning device. Therefore, the image adjustment generates a lot of waste developer as compared with normal image formation.

  Waste developer generated by image formation and image quality adjustment is collected in a waste developer container disposed in the image forming apparatus. After the waste developer container of the image forming device is full, if the printing process is performed after that, the waste developer overflows from the container and contaminates the machine, so the printing process is disabled. It is common to do.

  For example, in Patent Document 1, when a predetermined amount of waste developer is accumulated in the waste developer container, a message indicating the replacement timing of the waste developer container is displayed on the display unit, and then the waste developer container is full. An image forming apparatus is disclosed that, when judged, invalidates the printing process and displays a message prompting replacement of the waste developer container.

JP 2009-265281 A

  However, if the waste developer is accumulated up to a predetermined amount in the waste developer container, if the image quality adjustment is frequently performed, the waste developer collected in the waste developer container increases rapidly, so the waste developer Even if the container becomes full immediately and a message indicating the replacement timing of the waste developer container is displayed on the display section, the printing operation is invalidated before the replacement waste developer container is prepared, and the replacement waste developer is replaced. There was a risk that printing could not be performed until the container was prepared.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus in which a waste developer container does not become full immediately when a predetermined amount of waste developer is accumulated in the waste developer container.

In order to solve the above-described problem, a first technical means of the present invention includes a print processing unit that forms an image on a sheet by print processing, an image quality adjustment unit that performs image quality adjustment under a predetermined condition, and the image quality adjustment unit. Storage unit for storing parameter adjustment amount for image quality adjustment, waste developer container into which waste developer is charged, detection means for detecting the amount of waste developer, and image quality adjustment prohibiting image quality adjustment And the waste developer container is full when the detection means detects that a predetermined amount of the waste developer has accumulated in the waste developer container. A waste developer counter that counts to determine whether or not the waste developer counter has a means for prohibiting image formation by the print processing unit when the waste developer counter exceeds a predetermined number, The counter prints When the paper on which the image is formed by the processing unit is discharged and when the image quality adjustment is performed by the image quality adjusting unit, a predetermined number of values are increased, and the image quality adjustment is performed more than when the paper is discharged. The predetermined number to be increased is set to be larger when the operation is performed, and the image quality adjustment prohibiting means is configured such that the waste developer container is not full by the detection means and a predetermined amount of the waste developer has accumulated. Is detected, the adjustment amount of the adjustment parameter immediately before is acquired from the storage unit, and when the adjustment amount is smaller than a specified adjustment amount, the subsequent image quality adjustment is prohibited.

The second technical means is the first technical means further comprising a display unit, wherein when the detection unit detects that a predetermined amount of the waste developer has accumulated in the waste developer container, the display unit Is characterized in that information indicating that the predetermined amount of waste developer has accumulated in the waste developer container is displayed.

According to a third technical means, in the first or second technical means, the waste developer container is provided therein with a stirring member for stirring the waste developer, and the detection means is a rotational load of the stirring member. Based on the above, it is detected that the predetermined amount of the waste developer has accumulated in the waste developer container.

According to a fourth technical means, in the first or second technical means, the detection means has accumulated the predetermined amount of the waste developer in the waste developer container based on a weight of the waste developer container. It is characterized by detecting.

  According to the image forming apparatus of the present invention, when the detection unit detects that a predetermined amount of the waste developer has accumulated in the waste developer container, the image quality adjustment prohibiting unit prohibits the subsequent image quality adjusting unit. . Therefore, the image forming apparatus of the present invention can prevent the waste developer container from becoming full immediately due to image quality adjustment when the waste developer container is accumulated up to a predetermined amount. As a result, the number of printed sheets until the waste developer container is full can be increased. Further, it is possible to secure time for preparing a replacement waste developer container.

1 is a diagram illustrating a configuration of an image forming apparatus. FIG. 3 is an enlarged view showing a part of an image forming unit. It is a figure which shows the structure of a developing agent collection | recovery apparatus. It is a perspective view which shows the external appearance of a waste developer container. 1 is a block diagram illustrating a configuration of an image forming apparatus. It is a flowchart figure which determines the state of a waste developer container. FIG. 10 is a flowchart of processing for counting a waste developer counter. FIG. 6 is a flowchart for determining whether to prohibit execution of image quality adjustment.

FIG. 1 is a diagram illustrating a configuration of an image forming apparatus 50 according to an embodiment of the present invention.
The image forming apparatus 50 includes a plurality of image forming units including a photoconductor 61 on which an electrostatic latent image is formed and a developing unit 64 that develops the electrostatic latent image on the photoconductor 61 to form a developer image. 51, a print processing unit 41 including an image forming unit 51, an intermediate transfer member 52, and a transfer unit 53, a photosensitive member cleaning device 65, a transfer member cleaning device 54, and a paper feed for supplying recording paper The image forming apparatus includes a unit 55, a fixing unit 56, a paper discharge unit 57, a conveyance system that conveys recording paper within the apparatus main body, a humidity sensor (not shown) that measures humidity, and the like.

  A plurality of developer images formed on the photoreceptor 61 of the image forming unit 51 are stacked and transferred to the intermediate transfer member 52, and the transfer unit 53 receives the developer images transferred to the intermediate transfer member 52. Batch transfer onto recording paper as a transfer medium.

The photoconductor cleaning device 65 cleans a residual developer remaining on the photoconductor 61 without being transferred from the photoconductor 61 to the intermediate transfer body 52 or a patch image formed by image quality adjustment. The transfer body cleaning device 54 cleans the residual developer remaining on the intermediate transfer body 52 without being transferred from the intermediate transfer body 52 to the recording paper, or the patch image formed by image quality adjustment. Waste developer, which is a developer cleaned by the photoconductor cleaning device 65 and the transfer member cleaning device 54, is put into a waste developer container described later.
The fixing unit 56 fixes the developer image transferred onto the recording paper. The paper discharge unit 57 discharges the recording paper on which the developer image is fixed.

Hereinafter, each part of the image forming apparatus 50 will be described.
The image forming apparatus 50 of the present embodiment is a full color image forming apparatus. The image forming unit 51 separates image information and forms an image for each color. The image forming unit 51 is provided corresponding to four hues of black (k), yellow (y), magenta (m), and cyan (c). The four image forming units 51 only have different hues and have the same configuration. Therefore, the configuration of the image forming unit 51k for black (k) will be described as a representative, and the image forming units for other hues will be described. The description of 51 is omitted. In the present specification, for the configuration of the image forming unit 51, the photoconductor cleaning device 65, and the like provided for each color, an alphabet representing a color is given after the reference symbol for each, and only the reference symbol is used when referring collectively. Represented by

  The configuration of the image forming unit 51 will be described with reference to FIGS. 1, 2, and 4. FIG. 2 is an enlarged view of the image forming unit 51k. FIG. 4 is a perspective view showing the appearance of the waste developer container. The image forming unit 51k includes a photoreceptor 61k, a charger 62k, an exposure unit 63k, a developing unit 64k, and a photoreceptor cleaning device 65k. Each will be described below.

The photoreceptor 61k has a drum shape, and an electrostatic latent image is formed on the surface thereof. The photoconductor 61 can be replaced.
The charger 62k uniformly charges the surface of the photoconductor 61k. In this embodiment, a roller-type charger is used, and is arranged so as to be in contact with the outer peripheral surface of the photoconductor 61k. The charger is not limited to the roller charger, and for example, a brush charger, a charger charger, or the like may be used.

  The exposure unit 63k exposes the uniformly charged surface of the photoconductor 61k with light according to the image information of the black hue to form a black electrostatic latent image. The exposure unit 63k forms part of the exposure unit 70 together with the exposure unit 63 related to other hues. The exposure unit 70 generates an electrostatic latent image by irradiating each photoreceptor 61 with laser light for each hue based on image information used for image formation. The exposure unit 70 includes a laser scanning unit (abbreviated as LSU) 72 including a laser irradiation unit 71, a polygon mirror 73, and first and second reflection mirrors 74 and 63 that reflect laser light for each hue. The laser light emitted from the laser irradiation unit 71 is color-separated by the polygon mirror 73, and then reflected by the exposure unit, which is the first reflection mirror 74 and the second reflection mirror 63, so that each photoconductor for each hue. 61 is irradiated.

  The developing unit 64k visualizes the electrostatic latent image formed on the surface of the photoreceptor 61k by supplying black toner, which is a black developer. The photoconductor cleaning device 65k is disposed upstream of the charger 62k with respect to the rotation direction indicated by the arrow A of the photoconductor 61k. The developing unit 64 can be replaced.

  The photoconductor cleaning device 65k includes a cleaning blade 66k and a photoconductor waste developer transport device 67k. The cleaning blade 66k is disposed in contact with the outer peripheral surface of the photoconductor 61k, and scrapes off the developer remaining without being transferred to the intermediate transfer body 52 or the patch image formed by image quality adjustment from the surface of the photoconductor 61k. It has become. The photoreceptor waste developer transport device 67k transports the developer scraped by the cleaning blade 66k to a waste developer container described later.

  In the image forming unit 51 configured as described above, in the present embodiment, the black image forming unit 51k is disposed at a position farthest from a transfer roller 91 included in the transfer unit 53 described later, and the image forming unit 51 approaches the transfer roller 91. The image forming unit 51y for yellow, the image forming unit 51m for magenta, and the image forming unit 51c for cyan are arranged in this order.

  As shown in FIG. 1, the intermediate transfer member 52 is disposed above the image forming unit 51 and in contact with the photosensitive member 61. The intermediate transfer member 52 includes a transfer belt 81, a transfer belt driving roller 82, a transfer belt driven roller 83, a transfer belt tension mechanism 84, and an intermediate transfer roller 85. The intermediate transfer member 52 can be replaced. Four intermediate transfer rollers 85 (85k, 85y, 85m, and 85c) are provided corresponding to the image forming units 51 of the respective hues. The intermediate transfer member 52 forms a full-color toner image on the transfer belt 81 by sequentially superimposing and transferring the toner images of the respective colors formed on the photosensitive member 61 onto the transfer belt 81.

  The transfer belt 81 is stretched between the transfer belt driving roller 82 and the transfer belt driven roller 83 so that the outer surface of the transfer belt 81 is in contact with the outer peripheral surface of the photosensitive member 61, and tension is applied by the transfer belt tension mechanism 84. It is configured to be rotationally driven in the sub-scanning direction (the direction of arrow B in FIG. 1) by the rotational driving force of the transfer belt driving roller 82.

  The transfer belt drive roller 82 is disposed inside the housing 58 of the image forming apparatus 50 and near one end. The transfer belt drive roller 82 rotates the transfer belt 81 stretched in the direction of arrow B, and is sandwiched between the transfer roller 91 of the transfer unit 53 in a state where the transfer belt 81 and the recording paper are overlapped. It is provided so that the recording paper can be conveyed while being pressed.

  The transfer belt driven roller 83 is disposed inside the housing 58 and near the other end, and the transfer belt 81 is stretched together with the transfer belt driving roller 82.

  Each intermediate transfer roller 85 is provided in contact with the inner peripheral surface of the transfer belt 81 and in contact with the photoreceptor 61 via the transfer belt 81. The intermediate transfer roller 85 includes a shaft made of a metal (for example, stainless steel) having a diameter of 8 to 10 mm, and an elastic material having conductivity such as ethylene-propylene rubber (EPDM) or urethane foam is provided on the outer peripheral surface of the metal shaft. It is formed to cover. The intermediate transfer roller 85 configured as described above has a high voltage transfer bias, that is, a toner charging polarity (−), in order to transfer the toner image formed on the photosensitive member 61 to the transfer belt 81 of the intermediate transfer member 52. A high voltage having a reverse polarity (+) is applied, and the high voltage is uniformly applied to the transfer belt 81 by an elastic material. The toner images visualized according to the respective hues on the respective photoreceptors 61 are sequentially transferred and laminated on the transfer belt 81 by the intermediate transfer roller 85 to form a desired image to be formed.

  The transfer unit 53 includes a transfer roller 91. The transfer roller 91 is disposed so as to face the transfer belt drive roller 82 in a substantially horizontal and parallel manner, and to be in pressure contact with the transfer belt 81 wound around the transfer belt drive roller 82 with a predetermined nip. The The transfer roller 91 is applied with a voltage for transferring a full color toner image formed on the transfer belt 81 onto a recording sheet, that is, a high voltage having a polarity (+) opposite to the charging polarity (−) of the toner. Configured as follows.

  A registration roller 92 is provided below the transfer roller 91. The registration roller 92 conveys the leading end of a recording sheet supplied from a sheet feeding unit 55 described later and the leading end of a toner image on the transfer belt 81 to the transfer roller 91 in synchronization. The toner image formed on the transfer belt 81 is transferred to a recording sheet that passes through the nip between the transfer belt 81 and the transfer roller 91 by a high voltage applied to the transfer roller 91.

  On the side of the intermediate transfer member 52 where the driven roller 83 is disposed, a transfer member cleaning device 54 is disposed. The transfer member cleaning device 54 is a box-like member that temporarily stores a transfer member cleaning blade 93 provided in contact with the transfer belt 81 and a waste developer that is a developer scraped from the transfer belt 81 by the transfer member cleaning blade 93. A developer accommodating portion 94 and a transfer member waste developer conveying device 95 that is a device that is provided in the developer accommodating portion 94 and conveys the waste developer accommodated therein are included.

  As described above, the toner adhering to the transfer belt 81 due to contact with the photosensitive member 61 and / or the toner remaining without being transferred onto the recording paper in the transfer unit 53 prevents toner color mixing in the next process. Therefore, it is removed and collected by the transfer body cleaning device 54. The recording paper on which the toner images are collectively transferred in the transfer unit 53 is fixed in the fixing unit 56.

  The fixing unit 56 is provided above the transfer unit 53. The fixing unit 56 includes a heating roller 105 and a pressure roller 106. The fixing unit 56 fixes the toner image onto the recording paper by sandwiching the recording paper onto which the toner image has been transferred between the heating roller 105 and the pressure roller 106, and heating and pressing while rotating and conveying.

A paper discharge roller 108 is provided above the fixing unit 56, and the recording paper conveyed by the conveyance roller 107 is discharged onto a paper discharge tray which is a paper discharge unit 57 by the paper discharge roller 108.
A double-sided document conveyance path S3 for double-sided printing is provided adjacent to the fixing unit 56. The double-sided document conveyance path S3 is configured to convey again toward the transfer roller 91 in a state where the recording paper is reversed by each pair of first and second conveyance rollers 109 and 110 arranged in parallel on the conveyance path. Is done.

  Next, the paper feeding unit 55 that supplies recording paper to the transfer unit 53 will be described. The paper feeding unit 55 is provided below the image forming unit 51. The paper feed unit 55 includes a manual feed tray 111 and a paper feed cassette 112 that store recording paper used for image formation, and supplies recording paper from the manual feed tray 111 or the paper feed cassette 112 to the transfer unit 53 one by one. .

  The manual feed tray 111 is provided on one side of the casing 58 of the image forming apparatus 50 so as to be expanded outward when used, and storable on one side when not used. A small number of sheets (necessary number of sheets) are placed and taken into the housing 58 of the image forming apparatus 50 one by one. A pickup roller 113 is provided downstream of the exposure unit 70 on the downstream side in the paper feeding direction of the recording paper (arrow C direction in FIG. 1) by the manual feed tray 111, and further downstream in the paper feeding direction (C). Are provided with a pickup roller 113 and third to fifth transport rollers 114, 115, and 116, which constitute a recording paper transport path S1.

  The paper feed cassette 112 is disposed below the image forming unit 51 and the exposure unit 70 in the housing 58. The paper feed cassette can store recording paper. A pickup roller 117 is provided above one end of the paper feed cassette 112. The pickup roller 117 is in contact with the surface of one end of the recording paper at the top of the recording paper set in the paper feeding cassette 112 and reliably feeds and conveys the paper one by one with the frictional resistance of the roller. The transported recording sheet is transported upward by the transporting roller 118 to the transfer unit 53 along the recording sheet transporting path S1 formed on one end side in the housing 58.

  The image forming apparatus 50 described above can take a ready state in which the printing process can be performed and an energy saving state in which the energization of each unit is reduced and the printing process cannot be performed.

Hereinafter, an image forming operation by the image forming apparatus 50 of the present embodiment will be briefly described.
First, the outer peripheral surface of the photoreceptor 61 is uniformly charged to a predetermined potential by the charger 62. The charged photoconductor 61 is irradiated with laser light corresponding to the image information from the exposure unit 70, whereby an electrostatic latent image for each color is generated on each photoconductor 61. Next, developer toner is supplied from the developing unit 64 to the outer peripheral surface of the photoconductor 61, and the electrostatic latent image formed on the outer peripheral surface of the photoconductor 61 is visualized by the toner to form a toner image.

  The toner images for the respective colors formed on the photosensitive member 61 are sequentially laminated and transferred onto the transfer belt 81 of the intermediate transfer member 52 by the intermediate transfer roller 85 to form a full color toner image. The full-color toner image transferred onto the transfer belt 81 moves onto the recording paper supplied from the manual feed tray 111 or the paper feed cassette 112 of the paper feed unit 55 when the transfer belt 81 moves and reaches the transfer unit 53. On the other hand, when a transfer bias is applied by the transfer roller 91, the transfer is performed on the recording paper at once.

  The recording sheet on which the toner image has been transferred is conveyed to the fixing unit 56 where the toner image is thermally fixed on the recording sheet. The recording paper on which the toner image is fixed is discharged onto the paper discharge unit 57 by the paper discharge roller 108.

  Hereinafter, the operation of the image quality adjusting unit by the image forming apparatus 50 of the present embodiment will be briefly described. The image quality adjusting means is performed in the following procedure. First, by continuously changing the developing bias voltage on the surface of the photoconductor 61, a plurality of patch images with continuously changing toner density are formed. The toner density of these patch images is detected by toner density detecting means (not shown).

Then, the control unit 36 compares the density of the plurality of patch images whose toner density has been continuously changed with the reference toner density stored in advance in the memory 38, and determines the patch image having the toner density closest to the reference toner density. judge. Then, the developing bias voltage value applied to the patch image formation is specified.
Then, a toner image is formed on the surface of the photoreceptor 61 based on the specified development bias voltage value. Thereby, a toner image having a density equivalent to the reference toner density can be stably formed.

  The image quality adjustment method has been described by measuring a patch image formed on the surface of the photoreceptor 61. However, for example, a patch image formed on the intermediate transfer member 52 may be measured. The method using the developing bias voltage value as the adjustment parameter for adjusting the image quality has been described. However, the present invention is not limited to this. For example, the toner density can be changed by changing the charging voltage value of the photoconductor 61 or the like. May be adjusted.

  In the image forming process described above, residual toner is generated on the surface of the photoreceptor 61 and the surface of the transfer belt 81. In the image quality adjustment process, a patch image is generated on the surface of the photoreceptor 61 or the surface of the transfer belt 81. These are removed by the photosensitive member cleaning device 65 and the transfer member cleaning device 54. Residual toner and patch images removed from the surface of the photoreceptor 61 and the surface of the transfer belt 81 are conveyed into the waste developer container 2 by the photoreceptor waste toner transport device 67 and the transfer material developer transport device 95.

The developer recovery apparatus 1 will be described with reference to FIGS. FIG. 3A is a cross-sectional view illustrating a configuration of the developer recovery apparatus 1. FIG. 3B is a diagram illustrating a state in which the mechanical switch is turned on. FIG. 4 is a perspective view showing the external appearance of the waste developer container 2.
The developer recovery apparatus 1 includes a waste developer container 2, a stirring member 3, a mechanical switch 9, a gear mechanism that turns on the mechanical switch 9 when a predetermined load is applied to the stirring member 3, and power to the gear mechanism. And a driving source 26 to be applied.

The waste developer container 2 has a rectangular parallelepiped shape, is hollow inside, and has an internal space. The waste developer container 2 is made of, for example, a hard synthetic resin.
The waste developer container 2 is provided with an intake port 2 a for taking the waste developer into the internal space 16. The residual developer removed from the surface of the photoreceptor 61 and the surface of the transfer belt 81 is collected from the same intake port 2a. The stirring member 3 is rotatably supported in the internal space 16 of the waste developer container 2. The agitating member 3 agitates the waste developer accommodated in the internal space 16. Thus, the height position of the waste developer layer collected in the waste developer container 2 is made uniform, and the height position of the waste developer layer is prevented from becoming locally high.

  The gear mechanism includes a driving source 26 that applies a driving force, a gear 6 that is rotated by the driving source 26, a double-rotating gear 7 that is disposed on one side of the gear 6 and rotates coaxially with the gear 6, And a driving cam 4 that is rotated by a rotating gear 7.

The double rotation gear 7 has a gear 7a and a gear 7b. The gear 7a and the gear 7b are disposed so as to overlap on the same axis. These two rotation gears 7a and 7b can be separated from each other in the direction of the rotation axis.
The gear 7b rotates integrally with the gear 6. The gear 7b has a convex engagement surface with the rotating gear 7a. A concave engagement surface is formed on one surface of the gear 7a to engage with the gear 7b. On the other surface of the gear 7a, there is formed an engaging projection 8 that protrudes in parallel with the rotational axis from a position deviated from the rotational axis.
The convex portion of the gear 7 b is urged by the coil spring 10 to the concave portion of the gear 7 a.
The drive cam 4 is connected to the agitating member 3 and rotates integrally. The driving cam 4 is formed with an engaging recess 4a that engages with the engaging protrusion 8 at a position deviated from the rotation axis.

  The rotational driving force of the driving source 26 is transmitted to the driving cam 4 through the gear 6, the double rotating gear 7, and the engaging projection 8, and the stirring member 3 rotates as the driving cam 4 rotates. At this time, when the rotational load of the stirring member 3 increases, the rotational load of the gear 7a provided with the engagement protrusion 8 increases, and when the predetermined load is exceeded, slip occurs at the concave and convex engaging portions of the gear 7a and the gear 7b. . Due to this slip and the uneven shape of the gear 7a and the gear 7b, the gear 7b is separated in the axial direction away from the gear 7a against the spring force of the coil spring 10. At this time, the gear 7b moves along the rotation axis. The movement of the gear 7b moves the gear 6 in the same axial direction (the arrow direction in FIG. 3B).

  As shown in FIG. 3 (B), when the gear 7b and the gear 6 move in the direction of the arrow due to an increase in the rotational load of the stirring member, the mechanical switch is turned on. Thereby, it can be detected that the rotational load of the stirring member 3 has exceeded a predetermined load.

  The rotational load of the stirring member 3 correlates with the amount of waste developer carried to the waste developer container 2. That is, as the amount of waste developer increases, the rotational load on the stirring member also increases. Therefore, once the amount of waste developer to be detected is determined, the gear mechanism may be adjusted so that the double rotation gear 7 slips according to the load generated at that time.

  The amount of waste developer to be detected is set as appropriate. In the present embodiment, the height distance from the bottom of the waste developer container 2 to the intake port 2a is defined as h, and the waste developer is from the bottom of the waste developer container 2 to two-thirds of the height distance H. A state in which the accumulated state is desired to be detected. Since this state is not full but is almost full, it is defined as near full.

  In the present embodiment, the near fullness that is the first predetermined amount is detected by the rotational load of the stirring member, but the present invention is not limited to this. For example, the weight of the waste developer container 2 containing the waste developer in a state to be detected is weighed in advance, and the placement surface of the waste developer container 2 can be weighed. The first predetermined amount of near fullness and the second predetermined amount of fullness may be determined according to the weight of the waste developer container 2 containing the waste developer.

With reference to FIG. 5, image quality adjustment prohibiting means for prohibiting image quality adjustment will be described. FIG. 5 is a block diagram illustrating a configuration of the image forming apparatus 50.
The image forming apparatus 50 includes a control unit 36, a waste developer amount detection sensor 35, a print processing number detection unit 42, a display unit 37, a process control unit 43, and the like.

The control unit 36 is realized by a processing circuit such as a central processing unit (CPU), and includes a memory 38 that is a storage unit. The control unit 36 controls all operations of the image forming apparatus 50 and also functions as an image quality adjustment prohibiting unit described later. In addition, when the image quality adjustment is executed, the control unit 36 stores the development bias and the charging voltage value of the photoconductor 61 that are adjustment parameters before and after the image quality adjustment is executed in the memory 38. The control unit 36 also functions as a waste developer counter that counts the number of times by a predetermined method when printing or image quality adjustment is performed from near full. Further, when any of the photosensitive member 61, the developing unit 64, and the intermediate transfer member 52 is replaced, the control unit 36 receives a notification to that effect. Moreover, the control part 36 is controlled to switch a state from a ready state to an energy saving state, when a printing process is not performed even if predetermined time passes.
The waste developer amount detection sensor 35 detects a waste developer amount. In this embodiment, for example, the mechanical switch 9 is used.

The print processing sheet number detecting means 42 counts the number of recording sheets that have undergone the printing process. The number of recording sheets subjected to the printing process is realized by, for example, counting the passage of the recording sheet subjected to the printing process with a sensor. When the printing process is performed, the control unit 36 is notified.
The display unit 37 displays a message notifying that a predetermined amount of the waste developer has accumulated in the waste developer container 2, a message prompting replacement of the waste developer container 2, and the like according to an instruction from the control unit 36. These pieces of message information are stored in advance in the memory 38 of the control unit 36. The display unit 37 is realized by, for example, a liquid crystal display (LCD).

  The process control unit 43 is controlled by the control unit 36. Then, the process control unit 43 controls the print processing unit 41 and the cleaning units 54 and 65 to perform the printing process or the image quality adjustment process on the recording paper and the cleaning of the waste developer generated by the printing process or the image quality adjustment process. Etc. to control each part that executes etc. The cleaning units 54 and 65 control the waste toner conveying devices 67 and 95, the stirring member 3 of the waste developer container 2, and the like.

  The operation procedure of the image quality adjustment prohibiting unit will be described with reference to the flowcharts of FIGS. FIG. 6 is a flowchart for determining the state of the waste developer container. FIG. 7 is a flowchart of processing for counting the waste developer counter. FIG. 8 is a flowchart for determining whether to prohibit the execution of image quality adjustment.

  In this embodiment, it is possible to detect that the amount of waste developer is nearly full by turning on the mechanical switch 9, but it is not possible to detect a full state greater than near full. Estimating a full condition.

Hereinafter, a process for determining the state of the developer container 2 and a method for counting the waste developer counter will be described with reference to FIGS.
As shown in FIG. 6, the control unit 36 determines whether or not the mechanical switch is turned on (step S11). If the mechanical switch is turned on, it is determined whether or not the counter value of the waste developer counter exceeds a specified number (step S12).

  Here, the waste developer counter counts the value of the waste developer counter in the flow shown in FIG. A counting method of the waste developer counter will be described with reference to FIG. When the mechanical switch is turned on, the control unit 36 starts counting the waste developer counter. First, the control unit 36 determines whether or not the sheet is discharged (step S21). When the sheet is discharged, the waste developer counter is incremented by 1 (step S22), and the process returns to step S21. When the sheet is not discharged, the control unit 36 determines whether or not to execute image quality adjustment (step S23). When the image quality adjustment is executed, the control unit 36 increments the waste developer counter by 10 (step S24), and the process returns to step 21. When the image quality adjustment is not executed, the value of the waste developer counter is left as it is and the process returns to step S21. It should be noted that here, the execution of image quality adjustment generates a large amount of waste developer as compared with the normal printing process, so the value of the waste developer counter is increased by 10. Note that this value is set to an optimal value as appropriate according to the environment used.

  Returning to step S12 in FIG. 6, if the waste developer counter exceeds the specified number, the control unit 36 determines that the waste developer container 2 is full (step S13). If the waste developer counter is less than the specified number, it is determined that the waste developer container 2 is near full (step S14). If the mechanical switch is not ON in step S11, the control unit sets the waste developer counter stored in the memory 38 to 0 (step S15). Here, the prescribed number is 400, for example. This numerical value is set to an optimum value according to the actual machine. The state of the waste developer container 2 is stored in the memory 38 of the control unit 36.

  Next, a flow for determining whether or not image quality adjustment is prohibited will be described with reference to FIG. First, the control unit 36 determines whether or not the waste developer container 2 is full (step S1). If the waste developer container 2 is full, the print processing unit 41 is disabled so that the waste developer does not overflow from the waste developer container 2 (step S2). Further, it is determined whether or not the waste developer container 2 has been replaced (step S3). In step S3, when the waste developer container 2 is replaced, the control unit 36 enables the print processing unit 41 so that the print process can be performed (step S4), and the process returns to step S1.

If the waste developer container 2 is not full in step 1, it is determined whether or not the image quality adjustment execution condition is satisfied (step S5).
Here, when the image quality adjustment execution condition is satisfied, for example, at least one of the following conditions 1 to 5 may be satisfied.
Condition 1 is that when the fixing temperature is less than 60 ° C. when the power is turned on,
Condition 2 is that when the ready state continues for 12 consecutive hours or more,
Condition 3 is that when two or more hours have passed since the previous image quality adjustment, and the humidity at the time of the previous image quality adjustment and the current humidity is more than 20%,
Condition 4 is when it is detected that any one of the photosensitive member 61, the developing unit 64, and the intermediate transfer member 52 has been replaced
Condition 5 is a case in which conditions 1 to 4 are not met even if 24 hours or more have elapsed since the previous execution of image quality adjustment.

  If the execution condition of the image quality adjustment processing means is satisfied in step S5, it is determined whether or not the waste developer container 2 is near full (step S6). If the waste developer container 2 is not near full, image quality adjustment is executed (step S8). At this time, the control unit 36 stores a development bias voltage value, which is an adjustment parameter before and after execution of image quality adjustment, in the memory 38.

  When the image quality adjustment is executed, the control unit 36 compares the development bias voltage value before the image quality adjustment with the development bias voltage value after the image quality adjustment, calculates the adjustment amount, and the adjustment amount is smaller than the specified adjustment amount. Whether or not (step S9). If the adjustment amount is smaller than the specified adjustment amount, the control unit 36 sets the image quality adjustment prohibition flag on the memory 38 (step S10), and the process returns to step 1 again. If the adjustment amount is greater than or equal to the specified adjustment amount, the control unit 36 resets the image quality adjustment prohibition flag on the memory 38 (step S11) and returns to step 1 again. Here, the specified adjustment amount is, for example, 50V. When the image quality adjustment prohibition flag is set, after the waste developer container 2 is in a near full state, image quality adjustment is not performed thereafter.

Returning to step S6, if the waste developer container 2 is near full, it is determined whether the image quality adjustment prohibition flag is set on the memory 38 (step S7). If the image quality adjustment prohibition flag is set, the process returns to step 1. In step 1, when a print request is received, normal print processing is performed. Therefore, when the image quality adjustment prohibition flag is set in step S7, the image quality adjustment is not executed even if the image quality adjustment execution condition is satisfied. For this reason, the process which suppresses generation | occurrence | production of waste developer will be performed.
If the image quality adjustment prohibition flag is not set, the process moves to step 8 to execute image quality adjustment. Therefore, in this case, processing giving priority to high-quality printing is performed.

  As described above, the image forming apparatus 50 according to the present invention allows the subsequent image quality adjustment to be performed when the adjustment amount of the control parameter obtained by the previous image quality adjustment is smaller than the specified adjustment amount when the waste developer container is almost full. It will not be executed. Since the image quality adjustment is not executed, it is possible to suppress the waste developer container from being filled immediately due to the image quality adjustment. As a result, the number of printed sheets until the waste developer container 2 becomes full can be increased. Further, it is possible to secure time for preparing the replacement waste developer container 2.

  Although the adjustment parameter has been described using the development bias voltage value, the present invention is not limited to this. For example, the adjustment parameter may be a charging voltage value of the photosensitive member 61.

DESCRIPTION OF SYMBOLS 1 ... Developer collection apparatus, 2 ... Waste developer container, 3 ... Stirring member, 4 ... Drive cam, 6 ... Gear, 7 ... Double rotation gear, 8 ... Engagement protrusion, 9 ... Mechanical switch, 10 ... Coil Spring, 35 ... Waste developer amount detection sensor, 36 ... Control unit, 37 ... Display unit, 38 ... Memory, 41 ... Print processing unit, 42 ... Print processing number detection means, 43 ... Process control unit, 50 ... Image forming apparatus , 51 ... Image forming unit, 52 ... Intermediate transfer body, 53 ... Transfer section, 54 ... Transfer body cleaning device, 55 ... Paper feed section, 56 ... Fixing section, 57 ... Paper discharge section, 58 ... Housing, 61 ... Photosensitive , 62 ... charger, 63 ... exposure unit, 64 ... development unit, 65 ... photoconductor cleaning device, 66 ... cleaning blade, 67 ... photoconductor waste developer transport device, 70 ... exposure unit, 71 ... laser irradiation unit 71 72 ... Laser scanning uni 73 ... polygon mirror 74 ... first reflection mirror 81 ... transfer belt 82 ... transfer belt drive roller 83 ... transfer belt driven roller 84 ... transfer belt tension mechanism 85 ... intermediate transfer roller 91 ... transfer roller , 92 ... Registration roller, 93 ... Transfer cleaning blade, 94 ... Developer container, 95 ... Transfer waste developer conveying device, 105 ... Heating roller, 106 ... Pressure roller, 107 ... Conveying roller, 108 ... Discharge Roller 109 109 First transport roller 110 Second transport roller 111 Manual feed tray 112 Paper feed cassette Pickup roller 113 Third transport roller 114 Fourth transport roller 115 Fifth transport roller 116 117: Pickup roller, 118: Conveyance roller.

Claims (4)

A print processing unit for forming an image on the paper by printing;
Image quality adjusting means for adjusting image quality under predetermined conditions;
A storage unit for storing parameter adjustment amounts for image quality adjustment by the image quality adjustment means;
A waste developer container into which the waste developer is charged;
Detecting means for detecting the amount of the waste developer;
An image forming apparatus including image quality adjustment prohibiting means for prohibiting the image quality adjustment,
A waste developer counter that counts to determine whether the waste developer container is full when the detection unit detects that a predetermined amount of the waste developer has accumulated in the waste developer container; ,
Means for prohibiting image formation by the print processing unit when the waste developer counter exceeds a specified number;
The waste developer counter increments a predetermined number of values when the image-formed sheet is discharged by the print processing unit and when the image quality adjustment unit performs image quality adjustment, and the sheet is discharged. The predetermined number to be increased when the image quality adjustment is performed is set larger than when the image quality adjustment is performed,
When the detection unit detects that the waste developer container is not full and a predetermined amount of the waste developer has accumulated, the image quality adjustment prohibiting unit stores the adjustment amount of the adjustment parameter immediately before. The image forming apparatus is further characterized in that when the adjustment amount is smaller than a prescribed adjustment amount, the subsequent image quality adjustment is prohibited. A display unit;
When the detection unit detects that the predetermined amount of the waste developer has accumulated in the waste developer container, the display unit accumulates the predetermined amount of the waste developer in the waste developer container. The image forming apparatus according to claim 1, wherein information to the effect is displayed. The waste developer container is provided with a stirring member for stirring the waste developer inside.
Said detecting means, on the basis of the rotational load of the agitating member, the image forming according to claim 1 or 2, characterized in that for detecting that said predetermined amount of the waste developer in the waste developer container is accumulated apparatus. It said detecting means, based on the weight of the waste developer container, according to claim 1 or 2, characterized in that to detect that the waste developer of the predetermined amount to the waste developer container is accumulated Image forming apparatus.

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