JP2019066795A - Image forming apparatus and developer consumption suppressing method - Google Patents

Abstract

An object of the present invention is to prevent unnecessary consumption of a developer. A print processing unit Pr1 that forms an image on a medium to print and a developer deterioration index that indicates a deterioration state of a developer when printing is performed at a predetermined print duty is calculated based on a print duty threshold value. Developer degradation indicator operation unit, and a disposal processing necessity determination unit Pr2 that determines whether or not developer disposal processing needs to be performed depending on whether the developer degradation index is greater than the degradation index threshold, and developer disposal processing And a print duty threshold value setting unit Pr5 which sets the print duty threshold value corresponding to the amount of waste of the deteriorated developer. When printing is often performed at a low printing duty, the consumption amount of the developer can be suppressed by setting the printing duty threshold. [Selected figure] Figure 1

Description

  The present invention relates to an image forming apparatus and a developer consumption suppressing method.

  Conventionally, image forming apparatuses such as electrophotographic printers, copiers, facsimiles, multifunction machines, for example, printers are provided with a sheet cassette, an image forming unit, an LED head, a transfer roller, a fixing device, etc. The image forming apparatus includes a photosensitive drum, a charging roller, a developing roller, a toner supply roller, a developing blade, a toner cartridge, a cleaning blade, and the like.

  In the image forming unit, the surface of the photosensitive drum is charged by the charging roller, exposed by the LED head to form an electrostatic latent image, and the toner as the developer supplied from the toner cartridge is stabilized by the developing roller. The toner image is formed on the photosensitive drum by being attached to the latent electrostatic image.

  Then, the toner image is transferred to the sheet fed from the sheet cassette by the transfer roller, and fixed by the fixing device. In this way, an image is formed on the sheet.

  The toner remaining on the photosensitive drum after the toner image on the photosensitive drum is transferred to the sheet, that is, the residual toner is scraped off by the cleaning blade and removed to become waste toner, and the waste toner conveyance path It is transported and collected in a waste toner container.

  By the way, a toner storage unit for storing toner supplied from a toner cartridge is formed in the image forming unit, and in the toner storage unit, the toner supply roller supplies the toner to the developing roller, and the developing blade is developing A toner layer is formed on the roller, and the developing roller adheres the toner to the electrostatic latent image. At this time, the toner is charged by friction between the developing roller and the toner supply roller, further charged by friction between the developing roller and the developing blade, and attached to the electrostatic latent image to be used for printing. Be done.

  Then, the toner which is not attached to the electrostatic latent image and is not used for printing is sent to the toner storage unit with the rotation of the developing roller, mixed with the toner supplied from the toner cartridge, and again by the toner supply roller. It is supplied to the developing roller.

  Therefore, the toner not used for printing is repeatedly subjected to pressure by the developing roller, the toner supply roller, the developing blade, etc., and is heated by the heat generated by the friction accordingly, broken or pressed against other toners and integrated. It will be agglomerated and degraded.

  The thus deteriorated toner is accumulated as a deteriorated toner in the toner storage unit, supplied to the developing roller and attached to the electrostatic latent image to form a toner image, so when the image is formed, the image density is The printing quality may be degraded due to low or uneven.

  Therefore, there has been provided a printer in which degraded toner is intentionally attached to a photosensitive drum at a predetermined timing, scraped and removed by a cleaning blade, and collected by being collected in the waste toner container (discarded) (see FIG. See, for example, Patent Document 1).

  In addition, when a predetermined discarding condition is satisfied, a printer in which degraded toner is intentionally attached to a photosensitive drum, scraped and removed by a cleaning blade, and collected into the waste toner container to be discarded. Are provided (see, for example, Patent Document 2).

  In this type of printer, the discarding condition is satisfied when the print duty is lower than a threshold. The print duty is represented, for example, by the number of dots necessary to print in a printable area of a sheet of a predetermined paper size, and the print duty is high when the number of dots necessary to print is large. If the number of dots required to print is small, the print duty will be low.

  When printing is performed at a high printing duty, that is, high printing duty, the amount of toner used for printing is large, and a low printing duty, that is, low printing is possible while degraded toner is less likely to be accumulated in the toner storage unit. When printing is performed at duty, the amount of toner used for printing is small, and deteriorated toner is likely to be accumulated in the toner storage unit.

  Therefore, in the printer of Patent Document 2, when printing is performed with a low printing duty, the discarding condition is satisfied, and the deteriorated toner is discarded.

JP 2004-45481 A JP, 2015-121610, A

  However, in the conventional printer, since the deteriorated toner is always discarded when the print duty is lower than the threshold value, the amount of toner consumption is increased when printing is often performed with a low print duty. It becomes useless.

  An object of the present invention is to solve the problems of the conventional printer and to provide an image forming apparatus capable of preventing an increase in the amount of consumption of the developer unnecessarily.

  Therefore, in the image forming apparatus of the present invention, a printing process is performed in which a developer image is formed on an image carrier, the developer image is transferred to a medium, and the image is fixed by printing. And a developer deterioration index representing the deterioration state of the developer when printing is performed at a predetermined printing duty, to determine whether printing is performed at high printing duty or printing at low printing duty The developer deterioration index calculation unit, which is calculated based on the print duty threshold value, and whether or not the developer disposal processing needs to be performed is determined based on whether the developer deterioration index is larger than the deterioration index threshold value. And the waste processing execution part which executes the developer disposal processing when it is determined that the developer disposal processing needs to be performed, and the print duty threshold is set corresponding to the disposal amount of the deteriorated developer. And a print duty threshold setting unit for.

  According to the present invention, in the image forming apparatus, a printing process is performed in which a developer image is formed on an image carrier, the developer image is transferred to a medium, and the image is fixed by printing. And a developer deterioration index representing the deterioration state of the developer when printing is performed at a predetermined printing duty, to determine whether printing is performed at high printing duty or printing at low printing duty The developer deterioration index calculation unit, which is calculated based on the print duty threshold value, and whether or not the developer disposal processing needs to be performed is determined based on whether the developer deterioration index is larger than the deterioration index threshold value. The print duty threshold is set according to the waste processing execution part that executes the developer disposal processing when it is determined that the developer disposal processing needs to be performed, and the disposal amount of the deteriorated developer. And a print duty threshold setting unit.

  In this case, whether or not it is necessary to carry out the developer discarding process is judged depending on whether or not the developer deterioration index is larger than the deterioration index threshold, and it is determined that the developer discarding process needs to be carried out. Disposal processing is performed, and the print duty threshold is set corresponding to the amount of discarded developer that has been discarded.

  Therefore, when printing is often performed at a low printing duty, the consumption amount of the developer can be suppressed by setting the printing duty threshold value corresponding to the discarded amount of the deteriorated developer. As a result, the consumption of the developer can be prevented from becoming unnecessarily large.

FIG. 2 is a control block diagram of the printer in the first embodiment of the present invention. FIG. 1 is a conceptual view of a printer according to a first embodiment of the present invention. It is a flowchart which shows operation | movement of the printer in the 1st Embodiment of this invention. It is a figure which shows the subroutine of the printing process in the 1st Embodiment of this invention. It is a figure which shows the subroutine of the discard process necessity determination processing in the 1st Embodiment of this invention. It is a figure which shows the subroutine of the notification process in the 1st Embodiment of this invention. It is a figure which shows the subroutine of the notification necessity determination processing in the 1st Embodiment of this invention. It is a figure which shows the subroutine of the alerting | reporting process in the 1st Embodiment of this invention. It is a figure which shows the example of the notification message in the 1st Embodiment of this invention. It is a figure which shows the example of the adjustment menu in the 1st Embodiment of this invention. FIG. 6 is a diagram showing a subroutine of print duty threshold setting processing according to the first embodiment of the present invention. It is a control block diagram of a printer in a 2nd embodiment of the present invention. It is a flowchart which shows operation | movement of the printer in the 2nd Embodiment of this invention. It is a 1st figure which shows the subroutine of the toner discard mode setting process in the 2nd Embodiment of this invention. It is a 2nd figure which shows the subroutine of the toner discard mode setting process in the 2nd Embodiment of this invention. It is a figure which shows the example of the adjustment menu in the 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this case, a printer as an image forming apparatus will be described.

  FIG. 2 is a conceptual view of a printer according to the first embodiment of the present invention.

  In the figure, 10 is a printer, 20 is a main body of the printer 10, that is, an image forming unit (developing device) disposed detachably with respect to the apparatus main body B1, 21 is an LED head as an exposure device, 22 is an A sheet cassette as a medium storage unit disposed below the apparatus main body B1, a transfer roller 24 as a transfer member, and a fixing unit 25 as a fixing device.

  The image forming unit 20 is detachably mounted to the main body of the image forming unit 20, that is, the image forming unit main body 20a and the image forming unit main body 20a, and contains a developer as a developer. A toner cartridge 17 is provided as a part. A toner storage unit 18 as a developer storage unit is formed below the toner cartridge 17 in the image forming unit main body 20 a, and the toner supplied from the toner cartridge 17 is stored in the toner storage unit 18.

  Further, the image forming unit 20 is rotatably disposed so as to face the photosensitive drum 11 as an image bearing member and the photosensitive drum 11 and attach toner to the photosensitive drum 11 as a developer image. A developing roller 12 as a developer carrying member for forming a toner image, a toner supply roller 13 as a developer supplying member for supplying toner to the developing roller 12, and the photosensitive drum 11 are disposed so as to be rotatable. A charging roller 14 as a charging device for uniformly charging the surface of the photosensitive drum 11, a tip of the developing roller 12 is pressed against the developing roller 12, the toner supplied on the developing roller 12 is thinned, and a toner layer is formed. Developing blade 19 as a developer regulating member for forming toner, and cleaning resin for scraping and removing a residual toner as a transfer residual developer described later on the photosensitive drum 11 It scraped off by the cleaning blade 15 and the cleaning blade 15, as member comprises a waste toner conveyance path 16 as a waste developer conveying path for conveying the residual toner removed as waste toner is waste developer. In the present embodiment, an organic photosensitive drum is used as the photosensitive drum 11.

  The developing roller 12, the toner supply roller 13 and the developing blade 19 are disposed in the toner storage unit 18 to constitute a developing device.

  The LED head 21 is disposed above the image forming unit main body 20a so as to face the photosensitive drum 11, and exposes the photosensitive drum 11 charged by the charging roller 14 according to image data. An electrostatic latent image is formed on the surface 11 as a latent image, and the developing roller 12 forms a toner image on the photosensitive drum 11 by adhering toner to the electrostatic latent image.

  The transfer roller 24 is disposed below the image forming unit main body 20a so as to face the photosensitive drum 11, and the toner image on the photosensitive drum 11 is a sheet P as a medium supplied from the sheet cassette 22. Transfer to

  The fixing unit 25 includes a heating roller R1 as a first fixing member and a pressure roller R2 as a second fixing member, and a heating element such as a halogen lamp (not shown) is disposed in the heating roller R1. Ru. In the fixing unit 25, the toner image transferred to the sheet P is heated by the heating roller R 1, pressed by the pressure roller R 2, and fixed on the sheet P.

  After the toner image is transferred onto the sheet P, the toner remaining on the photosensitive drum 11 becomes residual toner, is scraped off and removed by the cleaning blade 15, and is dropped into the waste toner conveyance path 16 as waste toner. The transport path 16 is transported and collected in a waste toner container (not shown) as a waste developer storage unit disposed adjacent to the toner cartridge 17. For that purpose, a screw (not shown) as a conveying member for conveying the waste toner is disposed in the waste toner conveying path 16, and the waste toner is conveyed by rotating the screw.

  In the present embodiment, the toner cartridge 17 and the waste toner container are separately formed, but the toner cartridge 17 and the waste toner container can be integrally formed.

  Reference numeral 27 denotes a seal member which is formed of a film or the like and whose tip is pressed against the developing roller 12. The seal member 27 prevents the toner in the toner storage portion 18 from leaking out of the image forming unit main body 20 a.

  The photosensitive drum 11, the developing roller 12, the toner supply roller 13, the charging roller 14 and the transfer roller 24 are respectively rotated in the arrow direction.

  The sheet P in the sheet cassette 22 is delivered to the medium transport path Rt1 in the direction of arrow A by the delivery roller 23, transported by the transport roller m1 as a transport member, and between the photosensitive drum 11 and the transfer roller 24 (nip Section) in the direction of arrow B to transfer the toner image, and the fixing device 25 fixes the toner image to form an image. Subsequently, the sheet P is conveyed in the direction of the arrow C, and is discharged in the direction of the arrow D (outside the apparatus main body B1) by the discharge roller 26 as a discharge member.

  By the way, in the image forming unit 20, the toner supplied from the toner cartridge 17 and stored in the toner storage portion 18 is supplied to the developing roller 12 by the toner supply roller 13, and the toner is developed on the developing roller 12 by the developing blade 19. Layered and attached to the electrostatic latent image. At this time, the toner is charged by friction between the developing roller 12 and the toner supply roller 13, and further charged by friction between the developing roller 12 and the developing blade 19 to be adhered to the electrostatic latent image. , Used for printing.

  Then, the toner which is not attached to the electrostatic latent image and is not used for printing is sent to the toner storage unit 18 as the developing roller 12 rotates, mixed with the toner supplied from the toner cartridge 17, and again The developer is supplied to the developing roller 12 by the supply roller 13.

  Therefore, the toner not used for printing is repeatedly subjected to pressure by the developing roller 12, the toner supply roller 13, the developing blade 19 and the like, and is heated by the heat generated by the friction accordingly and broken or pressed against other toners. It becomes integrated, lumps, and deteriorates.

  The thus deteriorated toner is accumulated in the toner storage unit 18 as the deteriorated toner, supplied to the developing roller 12 and attached to the electrostatic latent image to form a toner image, so when the image is formed, The image density may be low or uneven, and the print quality may be degraded.

  Therefore, in the present embodiment, when the predetermined disposal condition is satisfied, toner disposal processing as developer disposal processing is performed, and the deteriorated toner is made to adhere to the photosensitive drum 11 and scraped off by the cleaning blade 15. Are removed and collected in the waste toner container to be discarded.

  Next, a control device of the printer 10 will be described.

  FIG. 1 is a control block diagram of a printer according to a first embodiment of the present invention.

  In the figure, 10 is a printer, Eg is a printer engine unit as an image forming unit, 31 is an operation unit operated by the operator, 32 is a display for displaying the operation state of the operation unit 31 by the operator, the condition of the printer 10, etc. A control unit 33 controls the entire printer 10, and a memory 34 is a storage device. The memory 34 includes storage members such as a ROM, a RAM, and an EEPROM. The printer 10 is connected to a host computer (not shown) as a higher-level device via a network, a cable and the like (not shown).

  The printer engine unit Eg includes image forming elements such as the photosensitive drum 11, the developing roller 12, the toner supply roller 13, the charging roller 14, the cleaning blade 15, the toner cartridge 17, the LED head 21, the transfer roller 24, and the fixing device 25. Prepare.

  The operation unit 31 includes a touch panel 36 as a first operation member and an operation keyboard 37 as a second operation member, and the display unit 32 includes a display panel 38 as a display member. The touch panel 36 is integrally formed with the display panel 38 and also functions as a display member.

  Further, the control unit 33 includes a CPU (not shown) including a microcomputer, and operates each image forming element of the printer engine unit Eg by executing a processing program recorded in the ROM of the memory 34, Processing, for example, printing processing based on print data transmitted from the host computer, the toner discarding processing for discarding the deteriorated toner accumulated in the toner storage unit 18 (FIG. 2), etc. are performed.

  Therefore, the control unit 33 includes a print processing unit Pr1, a discard processing necessity determination unit Pr2, a discard processing execution unit Pr3, a toner deterioration index calculation unit Pr4 as a developer deterioration index calculation unit, a print duty threshold setting unit Pr5 and A notification processing unit Pr6 is provided. The print processing is performed by the print processing unit Pr1, and the toner discarding process is performed by the discard processing necessity determination unit Pr2, the discard processing execution unit Pr3, the toner deterioration index calculation unit Pr4, the print duty threshold setting unit Pr5, and the notification processing unit Pr6. It will be.

  Then, information necessary for the control unit 33 to perform various processes such as printing process and toner discarding process is recorded in the memory 34. That is, in the present embodiment, a processing program for performing various processing such as printing processing and toner discarding processing is recorded in the ROM of the memory 34, and a host for performing printing processing in the RAM, EEPROM, etc. of the memory 34. Print data sent from a computer, image data generated by editing the print data, and a print duty threshold α, a print count value ct, and a toner deterioration index ε as a developer deterioration index for performing toner discard processing And the notification necessity determination threshold value β is recorded.

  The print duty threshold value α is a variable (load variable) representing a load applied to toner, which causes toner deterioration, and in the present embodiment, printing is performed with a high print duty, that is, a high print duty. It is a threshold of print duty for determining whether printing is performed at low print duty, that is, low print duty. When the print duty is equal to or greater than the print duty threshold α, it is determined that printing is performed at a high print duty, and when the print duty is smaller than the print duty threshold α, it is determined that printing is performed at a low print duty.

  The print duty is represented, for example, by the number of dots formed when printing in a printable area of a sheet of a predetermined sheet size, that is, the ratio of the number of dots in the printable area, and the number of dots When the proportion of the dot is high, the printing duty is high, and when the proportion of the number of dots is low, the printing duty is low.

  By the way, when printing is performed at a high printing duty, the amount of toner used for printing is large, and the deteriorated toner is used to form a toner image before being accumulated in the toner storage unit 18, so It is hard to accumulate in the storage unit 18. Therefore, when printing is often performed at a high printing duty, the printing quality does not deteriorate even if printing is continued without discarding the deteriorated toner.

  On the other hand, when printing is performed at a low printing duty, the amount of toner used for printing is small, and the deteriorated toner is easily accumulated in the toner storage unit 18. Therefore, when printing is often performed at a low print duty, if printing is continued without discarding the deteriorated toner, the print quality is degraded. However, if the degraded toner is discarded excessively, the amount of consumed toner becomes unnecessarily large.

  Therefore, in the present embodiment, the print duty threshold value is set (changed) by determining (changing) the print duty threshold value α for determining whether printing is performed at a high print duty or at a low print duty. The degraded toner is discarded according to α to adjust the print quality and the amount of consumed toner.

  For this purpose, a menu screen is formed on the display panel 38 of the display unit 32. On the menu screen, a menu for discarding degraded toner, that is, "DV roller cleaning" (cleaning of the photosensitive drum 11) described later. The adjustment menu (FIG. 10) is displayed. Then, in the adjustment menu, a plurality of, in the present embodiment, six setting values for adjusting the print quality and the consumption amount of toner are displayed, and the operator operates the operation unit 31 to perform predetermined operations. When the set value is selected, the control unit 33 sets the print duty threshold value α in six stages according to the selected set value.

  For example, in order to allow the consumption of toner to be large and not to reduce the print quality, the operator selects a predetermined set value to increase the print duty threshold α. As a result, the rate at which printing is determined to be performed at a low printing duty is increased, and the amount of degraded toner to be discarded, that is, the amount of discarded degraded toner is increased. As a result, since a lot of new toner is supplied from the toner cartridge 17 to the toner storage unit 18, the print quality is not reduced.

  On the other hand, when the print quality is allowed to deteriorate and the consumption amount of toner is not increased, the operator selects a predetermined set value to reduce the print duty threshold α. As a result, the rate at which it is determined that printing is performed at a high printing duty is increased, and the amount of discarded toner is reduced. As a result, the print quality is reduced.

  The print count value ct represents the number of times printing has been performed in the printer 10, that is, the number of printed pages. A print counter (not shown) disposed in the control unit 33 increments the print count value ct each time printing of one page is performed in the printer 10.

  The toner deterioration index ε is an index indicating the toner deterioration state when printing is performed at a predetermined printing duty, and in the control unit 33, when the discarding process necessity determination unit Pr2 ends printing, Based on the toner deterioration index ε, it is determined whether or not it is necessary to perform the toner discarding process, that is, whether it is necessary to perform the toner discarding process. In the present embodiment, the toner deterioration index ε takes a value in the range of “127” to “−128”, and changes in accordance with the printing duty when printing is performed.

  That is, when it is determined that the upper limit value on the high printing duty side is “−128”, the upper limit value on the low printing duty side is “127”, and it is determined that printing is performed at the high printing duty. When it is determined that printing is performed with low print duty, it is incremented (one by 1) in the positive direction, and when printing is frequently performed with low print duty. The size increases in the positive direction, and increases in the negative direction when printing is frequently performed at a high print duty.

  Further, for example, when printing of the print job Job1 is performed, the toner deterioration index ε is calculated by the following method based on the print duty threshold α.

  A photosensitive drum that is rotated from the start of printing of the print job Job1 to the end when the count value representing the number of dots formed from the start to the end of printing of the print job Job1 is the dot count value Dot. A count value representing the number of revolutions of 11 is taken as a drum count value Drum.

  Then, assuming that the print duty is equal to the print duty threshold α and the dot count value representing the print load when printing the print job Job 1 is made the reference dot count value Dot (S) as the reference print load, the reference dot The count value Dot (S) is calculated by the following equation (1).

Dot (S) = (792/5) × α × 8192 × Drum (1)
Here, “792/5” is per printing duty 1 [%] when printing is performed at a printing duty of 5 [%] in the printable range of the vertical A4 size paper P, that is, per unit printing duty , Is a dot count value representing the number of dots formed. Therefore, (792/5) × α is a dot count value when printing is performed on A4 size paper P with the print duty equal to the print duty threshold α. Also, "8192" represents a 13-bit shift.

  Next, the amount of change of the toner deterioration index ε by printing the print job Job1 at a predetermined print duty, that is, the increase or decrease Δε of the toner deterioration index ε is calculated.

  The increase / decrease amount Δε is a reference dot count value Dot (S) when printing is performed with the print duty equal to the print duty threshold α, and a dot count value Dot when the print job Job1 is printed with the predetermined print duty. And is calculated by the following equation (2).

Δε = Dot (S) −Dot (2)
Therefore, the toner deterioration index calculation unit Pr4 of the control unit 33 adds the increase / decrease Δε to the toner deterioration index ε when printing of the print job Job1 is started according to the following equation (3). The toner deterioration index ε at the end of printing is calculated.

ε = ε + Δε (3)
When printing of the print job Job1 is performed at a low print duty lower than the print duty threshold α, the dot count value Dot becomes smaller than the reference dot count value Dot (S), and the increase or decrease Δε takes a positive value. As a result, the toner deterioration index ε when printing of the print job Job1 ends is larger than the toner deterioration index ε when printing of the print job Job1 starts.

  On the other hand, when printing of the print job Job1 is performed at a high print duty higher than the print duty threshold α, the dot count value Dot becomes larger than the reference dot count value Dot (S), and the increase or decrease Δε is a negative value. take. As a result, the toner deterioration index ε when printing of the print job Job1 ends is smaller than the toner deterioration index ε when printing of the print job Job1 is started.

  Further, the notification necessity determination threshold β determines whether to notify the operator by displaying on the display panel 38 a notification message prompting suppression of the toner consumption amount when the discarded toner amount is large. Threshold for When the discard amount of degraded toner per print count value ct, that is, the discarded amount of degraded toner each time printing of one page is larger than the notification necessity determination threshold β, a notification message is displayed on the display panel 38 .

  Next, the print processing unit Pr1, the discard processing necessity determination unit Pr2, the discard processing execution unit Pr3, the toner deterioration index calculation unit Pr4, the print duty threshold setting unit Pr5, and the notification processing unit Pr6 of the control unit 33 will be described.

  Upon receiving the print data from the host computer, the print processing unit Pr1 generates image data based on the print data, operates the printer engine unit Eg, and prints a print job.

  That is, the print processing unit Pr1 sends the image data to the LED head 21, forms a toner image on the photosensitive drum 11 in the image forming unit 20, transfers the toner image onto the sheet P by the transfer roller 24, and The toner image is fixed to the sheet P, and the image is formed on the sheet P.

  Then, when printing by the print processing unit Pr1 is completed, the discard process necessity determination unit Pr2 reads the toner deterioration index ε from the memory 34 using the timing at which printing of the print job is finished as a trigger, and the condition for discarding deteriorated toner is Whether it is necessary to perform the toner discarding process is determined depending on whether or not the condition is satisfied.

  In the present embodiment, the timing at which printing of the print job ends is used as a trigger. For example, when the power of the printer 10 is turned on, the toner cartridge 17 and the image forming unit 20 are used. When printing is performed on a predetermined number of sheets, for example, 64 sheets of paper P, when continuous printing is performed when a housing cover (not shown) of the printer 10 is opened and closed in order to replace etc. It is also possible to determine whether it is necessary to perform the toner discarding process triggered by the timing when a predetermined event occurs, such as when printing of the next print job is started.

  Further, the discarding process execution unit Pr3 executes the toner discarding process when it is determined by the discarding process necessity determination unit Pr2 that the toner discarding process needs to be performed, and the deteriorated toner accumulated in the toner storage unit 18 Discard

  For that purpose, the discarding process execution unit Pr3 sends data for the toner discarding process to the LED head 21 and exposes the photosensitive drum 11 with a preset exposure pattern, that is, the toner discarding pattern as the developer discarding pattern, An electrostatic latent image for discarding degraded toner, that is, an electrostatic latent image for disposal is formed on the surface of the photosensitive drum 11, and toner is attached to the electrostatic latent image for disposal from the developing roller 12, A waste developer image is formed on the drum 11.

  The toner waste pattern is set, for example, over an area of 28.644 mm in the printable range of the sheet P on the photosensitive drum 11.

  Subsequently, the discarding process execution unit Pr3 rotates the photosensitive drum 11 while keeping the toner on the photosensitive drum 11, that is, without transferring the waste developer image on the photosensitive drum 11. As a result, the toner of the waste developer image is scraped off and removed by the cleaning blade 15, falls as waste toner to the waste toner conveyance path 16, is conveyed through the waste toner conveyance path 16, and is collected in the waste toner container. Ru. Although the external additive separated from the toner may be deposited on the waste toner conveyance path 16, the external additive is conveyed along the waste toner conveyance path 16 together with the waste toner and collected in a waste toner container. Thus, the toner discarding process is executed, and the deteriorated toner accumulated in the toner storage unit 18 is discarded.

  The data for the toner discarding process is generated in advance and recorded in the ROM of the memory 34.

  The waste toner container can be removed from the image forming unit main body 20a when the toner cartridge 17 is replaced, and can be emptied.

  Further, the toner deterioration index computing unit Pr4 calculates the toner deterioration index ε by the equations (1) to (3) after the toner discarding process is performed by the discarding process execution unit Pr3.

  Further, the print duty threshold setting unit Pr5 sets the print duty threshold α in accordance with the amount of discarded deteriorated toner. That is, when the operator selects the setting value of the adjustment menu of the “DV roller cleaning” according to the discard amount of the deteriorated toner, the printing duty threshold value setting unit Pr5 selects the print duty threshold according to the setting value of the adjustment menu. Set α.

  Next, the operation of the printer 10 will be described.

  FIG. 3 is a flowchart showing the operation of the printer according to the first embodiment of the present invention, FIG. 4 is a diagram showing a subroutine of printing processing according to the first embodiment of the present invention, and FIG. 5 is a first embodiment of the present invention FIG. 6 is a diagram showing a subroutine for discard processing necessity determination processing in the embodiment, FIG. 6 is a diagram showing a subroutine for notification processing in the first embodiment of the present invention, and FIG. 7 is a diagram in the first embodiment of the present invention FIG. 8 is a diagram showing a subroutine of notification necessity determination processing, FIG. 8 is a diagram showing a subroutine of notification processing in the first embodiment of the present invention, and FIG. 9 is an example of a notification message in the first embodiment of the present invention FIG. 10 shows an example of an adjustment menu in the first embodiment of the present invention, and FIG. 11 shows a subroutine of print duty threshold setting processing in the first embodiment of the present invention That.

  First, the control unit 33 determines whether there is a print request from the host computer based on whether print data has been received from the host computer.

  When print data is received from the host computer and there is a print request, the print processing unit Pr1 performs print processing. In the printing process, the print processing unit Pr1 generates image data based on the print data, operates the printer engine unit Eg, performs printing for a print job, and prints one page each time printing is completed. Increment (add 1).

  When printing by the print processing unit Pr1 is completed, the discarding process necessity determination unit Pr2 performs a discarding process necessity determination process triggered by the timing at which printing of the print job is completed. For example, when printing is often performed at a low printing duty and the toner deterioration index ε increases in the positive direction, the discard processing necessity determination unit Pr2 reads the toner deterioration index ε from the memory 34, and Whether the condition for discarding the deteriorated toner is satisfied is determined depending on whether the deterioration index ε is larger than 1 which is the deterioration index threshold.

  If the toner deterioration index ε is larger than 1 and the condition for discarding deteriorated toner is satisfied, the discard processing necessity determination unit Pr2 determines that the toner discard processing needs to be performed, and the toner deterioration index ε is a predetermined value, this value In the embodiment, it is decremented by one.

  Also, for example, when printing is not performed at a low printing duty and the toner deterioration index ε is large in the negative direction, the toner deterioration index ε is 1 or less and the toner discarding condition is not satisfied. The discarding process necessity determination unit Pr2 determines that it is not necessary to perform the toner discarding process.

  If it is determined by the discard processing necessity determination unit Pr2 that toner discard processing needs to be performed, the discard processing execution unit Pr3 operates the printer engine unit Eg to perform discard processing execution processing.

  To that end, the waste processing execution unit Pr3 exposes the photosensitive drum 11 with the toner waste pattern, causes the developing roller 12 to adhere toner to the waste electrostatic latent image, and causes the waste developer image to be deposited on the photosensitive drum 11. Form. Subsequently, the waste processing execution unit Pr3 rotates the photosensitive drum 11 without transferring the waste developer image on the photosensitive drum 11, and scrapes the toner of the waste developer image with the cleaning blade 15 and removes it. . Thus, the degraded toner is discarded.

  When the execution of the toner discarding process by the discarding process execution unit Pr3 is completed, the toner deterioration index calculation unit Pr4 performs the toner deterioration index calculation process to calculate the toner deterioration index ε by the above formulas (1) to (3). The toner deterioration index ε is recorded in the memory 34.

  Subsequently, the notification processing unit Pr6 performs notification processing to urge the operator to change the print duty threshold α.

  In this case, the notification processing unit Pr6 calculates the discard amount of the deteriorated toner discarded in the discard processing, that is, the toner discard amount Q, and performs notification processing based on the toner discard amount Q. The toner discarding amount Q is calculated based on the size of the toner discarding pattern.

  When continuous printing is performed, it is determined whether toner disposal processing is to be performed when printing is performed on a predetermined number of sheets P, for example, 64 sheets, and toner disposal processing is performed. In this case, the notification processing unit Pr6 performs the notification processing in parallel with the discarding processing execution processing by the discarding processing execution unit Pr3, and calculates an accumulated value ΣQ of the toner discarding amount Q discarded in the discarding processing execution processing.

  Next, the notification processing unit Pr6 performs notification necessity determination processing, reads the print count value ct from the memory 34, and the print count value ct is 100 or more (the printing is performed in the print processing by the print processing unit Pr1 Whether or not the number of pages is equal to or more than 100 [pages] determines whether the first notification requirement is satisfied.

When the print count value ct is 100 or more and the first notification necessary condition is satisfied, the notification processing unit Pr6 calculates the toner discard amount Q, or counts the cumulative value ΣQ when printing is performed continuously. Unit waste amount ΔQ, which is the toner waste amount Q per printing count value ct divided by the value ct
ΔQ = Q / ct (or QQ / ct)
Calculate

  Then, the notification processing unit Pr6 performs the notification necessity determination process, reads the notification necessity determination threshold value β from the memory 34, and determines whether the second discard is necessary depending on whether the unit discard amount ΔQ is larger than the notification necessity determination threshold value β. It is determined whether the condition is satisfied, that is, whether the degraded toner is frequently discarded and notification is necessary. When the discarded toner is frequently discarded and the unit discard amount Q is larger than the notification necessity determination threshold value β, the notification processing unit Pr6 determines that the second notification requirement is satisfied and the notification is necessary. If the degraded toner is not discarded so much and the unit discard amount Q is equal to or less than the notification necessity determination threshold β, the notification processing unit Pr6 does not satisfy the second notification requirement and does not require notification. It is determined that

  Subsequently, the notification processing unit Pr6 determines whether it is determined that the notification is necessary in the notification necessity determination process, and when it is determined that the notification is necessary, the notification process is performed and the notification is not necessary. If it is determined, the process ends.

  In the case where the print count value ct is smaller than 100 (the number of pages on which printing is performed in the print processing by the print processing unit Pr1 is smaller than 100 [sheets]) and the first notification requirement does not hold, a slight page is required. Whether or not the second notification requirement is satisfied is performed in order to prevent the determination that the printing is performed frequently with a low printing duty based on the printing duty in the number printing. Absent.

Then, in the notification process, the notification processing unit Pr6 creates a message prompting the operator to change the print duty threshold α, that is, creates a notification message, forms a message display screen (not shown) on the display panel 38, and displays the message. On the screen, as shown in Figure 9,
"If you want to reduce the amount of print consumption and reduce the amount of toner consumption, change the setting in the [DV Roller Cleaning] adjustment menu to a larger value."
While displaying the adjustment menu of [DV roller cleaning] for setting the print duty threshold value α as shown in FIG.

  In the adjustment menu, six setting values of 0, +1, +2, +3, +4, +5 are displayed, among which the currently selected setting value, that is, the setting value of 0 in FIG. Highlighted by etc.

  The smaller the set value, the smaller the set print duty threshold α, and the larger the set value, the larger the set print duty threshold α.

  Then, when the control unit 33 receives no print data from the host computer and there is no print request from the host computer, the control unit 33 determines whether there is a change request for the print duty threshold value α by the operator based on notification processing. to decide.

  That is, when the setting value is selected in the adjustment menu by the operator, data representing the setting value is sent from the touch panel 36 to the control unit 33. Therefore, control unit 33 determines whether or not there is a change request for print duty threshold value α based on whether data representing the setting value has been sent from touch panel 38 or not. When data representing the set value is sent from the touch panel 36 and there is a request for changing the print duty threshold value α, the print duty threshold setting unit Pr5 performs the print duty threshold setting processing, and when there is no change request, the control unit 33 performs processing. finish.

  In the print duty threshold setting process, the print duty threshold setting unit Pr5 acquires the set value selected by the operator on the adjustment menu based on the data representing the set value, and the print duty threshold α is set according to the set value. Set (change).

  The operator sets (changes) the setting value of the adjustment menu to a large value in order to allow the deterioration of the printing quality and suppress the consumption of toner when there is a large amount of toner discarded by the toner discarding process. When the amount of toner discarded by the discarding process is small, the setting value of the adjustment menu is set to a small value in order to improve the print quality without suppressing the toner consumption.

  When the setting value of the adjustment menu is set to a large value, the print duty threshold setting unit Pr5 increases the print duty threshold α, and the toner deterioration index ε calculated by the print duty threshold setting unit Pr5 decreases accordingly. Therefore, it becomes difficult to establish the toner discarding condition. As a result, it is possible to reduce the amount of discarded toner due to the toner disposal process and to suppress the consumption of toner.

  In addition, when the setting value of the adjustment menu is set to a small value, the print duty threshold setting unit Pr5 decreases the print duty threshold α, and accordingly, the toner deterioration index ε calculated by the print duty threshold setting unit Pr5 is As the size of the toner increases, it becomes easy to establish the toner discarding condition. As a result, it is possible to increase the amount of toner discarded by the toner disposal process and to improve the printing quality.

  In the present embodiment, the initial value of the print duty threshold α is set to a predetermined value according to the specifications of the printer 10. Further, how the print duty threshold α is changed when the operator selects the set value in the adjustment menu is set in advance, and each set value and the print duty threshold α are made to correspond to each other and the memory 34 is displayed. It is recorded.

  As described above, in the present embodiment, it is determined whether it is necessary to perform the toner discarding process depending on whether the toner deterioration index ε is larger than the deterioration index threshold, and it is determined that the toner discarding process needs to be performed. In this case, the toner discarding process is executed, and the print duty threshold α is set in correspondence with the amount of discarded deteriorated toner.

  Therefore, when printing is often performed at a low printing duty, the toner consumption amount can be suppressed by setting the printing duty threshold value α in accordance with the discarded toner amount. As a result, it is possible to prevent the toner consumption from becoming unnecessarily large.

Next, the flowchart of FIG. 3 will be described.
Step S1 The controller 33 determines whether there is a print request from the host computer. If there is a print request from the host computer, the process proceeds to step S2, and if there is no print request from the host computer, the process proceeds to step S7.
Step S2 The print processing unit Pr1 performs print processing.
Step S3: Disposal processing necessity determination part Pr2 performs disposal processing necessity determination processing.
Step S4 The discarding process execution unit Pr3 performs a discarding process execution process.
Step S5 The toner deterioration index calculation unit Pr4 performs toner deterioration index calculation processing.
Step S6 The notification processing unit Pr6 performs notification processing, and ends the processing.
Step S7 The controller 33 determines whether there is a request for changing the print duty threshold α. If there is a change request for the print duty threshold value α, the process ends in step S8. If there is no change request for the print duty threshold value α, the process ends.
Step S8 The print duty threshold setting unit Pr5 performs print duty threshold setting processing, and ends the processing.

Next, the flowchart of FIG. 4 will be described.
Step S2-1 The print processing unit Pr1 operates the printer engine unit Eg to print a print job.
Step S2-2 The print processing unit Pr1 increments the print count value ct and returns.

Next, the flowchart of FIG. 5 will be described.
Step S3-1 The discard processing necessity determination unit Pr2 determines whether the toner deterioration index ε is larger than one. If the toner deterioration index ε is larger than 1, the process proceeds to step S3-2. If the toner deterioration index ε is 1 or less, the process returns.
Step S3-2 Discarding process necessity determination unit Pr2 determines that it is necessary to perform the toner discarding process.
Step S3-3 The discard processing necessity determination unit Pr2 decrements the toner deterioration index ε by 1 and returns.

Next, the flowchart of FIG. 6 will be described.
Step S6-1: The notification processing unit Pr6 calculates the toner discarding amount Q.
Step S6-2 The notification processing unit Pr6 calculates an accumulated value ΣQ of the toner discarding amount Q.
Step S6-3 The notification processing unit Pr6 performs notification necessity determination processing.
Step S6-4: The notification processing unit Pr6 determines whether it is determined that notification is necessary. If it is determined that the notification is necessary, the process proceeds to step S6-5, and if it is determined that the notification is unnecessary, the process returns.
Step S6-5: The notification processing unit Pr6 performs notification processing and returns.

Next, the flowchart of FIG. 7 will be described.
Step S6-3-1 The notification processing unit Pr6 determines whether the print count value ct is 100 or more. If the print count value ct is 100 or more, the process proceeds to step S6-3-2, and if the print count value ct is smaller than 100, the process returns.
Step S6-3-2 The notification processing unit Pr6 calculates the unit discard amount ΔQ.
Step S6-3-3 The notification processing unit Pr6 determines whether the unit discard amount ΔQ is larger than the notification necessity determination threshold β. If the unit discard amount ΔQ is larger than the notification necessity determination threshold β, the process proceeds to step S6-3-4. If the unit discard amount ΔQ is less than the notification necessity determination threshold β, the process proceeds to step S6-3-5.
Step S6-3-4: The notification processing unit Pr6 determines that notification is unnecessary, and returns.
Step S6-3-5: The notification processing unit Pr6 determines that notification is necessary, and returns.

Next, the flowchart of FIG. 8 will be described.
Step S6-5-1 The notification processing unit Pr6 creates a notification message.
Step S6-5-2 The notification processing unit Pr6 displays a notification message and returns.

Next, the flowchart of FIG. 11 will be described.
Step S8-1 The print duty threshold value setting unit Pr5 acquires the setting value selected by the operator in the adjustment menu.
Step S8-2: The print duty threshold setting unit Pr5 sets the print duty threshold α and returns.

  By the way, in a printer having a function of suppressing the consumption of toner used for printing, that is, a toner save function of the consumable consumption suppression function, the operator usually uses the menu screen formed on the display panel. Mode or toner save mode can be selected, and when toner save mode is selected, predetermined processing is performed on image data, or toner of a toner image formed on a photosensitive drum is As a result, the density of the image formed on the sheet, ie, the image density, is lowered.

  Therefore, in the printer 10 according to the present embodiment, when the toner save mode is selected and set, the print quality is not important. However, in the case where printing is performed with the toner save mode set and the case where printing is performed without the toner save mode are compared when the print duty threshold α is the same, the toner save mode is set. When printing is performed in the above state, when the toner of the toner image formed on the photosensitive drum 11 is thinned, the amount of the residual toner increases. In this case, when the toner discarding process is performed with the toner save mode set, the toner discarding amount Q increases.

  Therefore, a second embodiment of the present invention will be described in which the waste toner disposal process and the toner save function are linked. The same reference numerals are given to those having the same structure as in the first embodiment, and the effects of the same embodiment are incorporated for the effects of the invention by having the same structure.

  FIG. 12 is a control block diagram of the printer in the second embodiment of the present invention.

  In the figure, reference numeral 33 denotes a control unit, which is a print processing unit Pr1, a discard process necessity determination unit Pr2, a discard process execution unit Pr3, and a toner deterioration index calculation unit Pr4 as a developer deterioration index calculation unit. The toner disposal mode setting unit Pr11 and the notification processing unit Pr6 are provided as a developer disposal mode setting unit.

  In this case, in the printer 10 as the image forming apparatus, printing can be performed using the toner save function, and the print processing unit Pr1 performs the normal mode without using the toner save function, and the toner save function. Printing can be performed in the toner save mode using the.

  Further, information necessary for the control unit 33 to perform various processes such as printing process and toner discarding process is recorded in the memory 34 as a storage device. That is, in the present embodiment, a processing program for performing various processing such as printing processing and toner discarding processing is recorded in the ROM of the memory 34, and a host program for performing printing processing in the RAM, EEPROM, etc. of the memory 34. Print data transmitted from a host computer as an apparatus, image data generated by editing the print data, and toner save mode set value Msj (j = 1, 2,...) For printing in the toner save mode The print duty threshold α, the print count value ct, the toner deterioration index ε as a developer deterioration index, the notification necessity determination threshold β, and the toner discard mode set value Mdi for performing the toner waste processing. i = 1, 2, ...) is recorded.

  The print duty threshold α is a variable (load variable) representing a load applied to the toner, which causes the toner as a developer to deteriorate, and printing is performed at a high print duty as in the first embodiment. This is a print duty threshold for determining whether printing is performed or printing is performed at a low print duty.

  In the present embodiment, a menu screen is formed on the display panel 38 as a display member of the display unit 32 of the printer 10 in order to link the disposal process of the degraded toner and the toner save function, and the menu screen is degraded. A menu for discarding the toner, that is, an adjustment menu of “DV roller cleaning” is displayed, and in the adjustment menu, a plurality of, in the present embodiment, four toner discard modes as developer discard modes are displayed. Is displayed. The toner discarding mode setting unit Pr11 sets the toner discarding mode according to the toner discarding mode of the adjustment menu when the toner discarding mode is selected by the operator in the “DV roller cleaning” adjustment menu, and the selected toner is selected. The print duty threshold α is set (changed) based on whether the discard mode and the toner save mode are set.

  For example, in order to allow the consumption of toner to be large and not to reduce the print quality, the operator selects a predetermined toner disposal mode to increase the print duty threshold α. As a result, the toner deterioration index ε is increased, and the amount of discarded toner is increased. As a result, since a large amount of new toner is supplied from the toner cartridge 17 as the developer storage portion to the toner storage portion 18 as the developer storage portion, the print quality is not reduced.

  On the other hand, in the case where the print quality is allowed to deteriorate and the toner consumption amount is suppressed, the operator selects a predetermined toner discarding mode to reduce the print duty threshold α. As a result, the toner deterioration index ε becomes smaller, and the amount of discarded toner is reduced. As a result, since new toner is not supplied from the toner cartridge 17 to the toner storage unit 18, the print quality is lowered.

  Next, the operation of the printer 10 will be described.

  FIG. 13 is a flowchart showing the operation of the printer according to the second embodiment of the present invention, FIG. 14 is a first diagram showing a subroutine of toner discarding mode setting processing according to the second embodiment of the present invention, and FIG. FIG. 16 is a second diagram showing a subroutine of toner discarding mode setting processing in the second embodiment of the present invention, and FIG. 16 is a diagram showing an example of an adjustment menu in the second embodiment of the present invention.

  First, the control unit 33 determines whether there is a print request from the host computer based on whether print data has been received from the host computer.

  When print data is received from the host computer and there is a print request, the print processing unit Pr1 performs print processing and performs printing for a print job in the normal mode or the toner save mode.

  When printing by the print processing unit Pr1 is completed, the discarding process necessity determination unit Pr2 performs the discarding process necessity determination process triggered by the timing at which printing of the print job is completed, depending on whether the toner deterioration index ε is greater than 1 or not. It is determined whether the condition for discarding degraded toner is satisfied.

  If the toner deterioration index ε is larger than 1 and the condition for discarding deteriorated toner is satisfied, the discarding process execution unit Pr3 operates the printer engine unit Eg as an image forming unit to perform a discarding process execution process.

  When the toner discarding process by the discarding process execution unit Pr3 is completed, the toner deterioration index calculation unit Pr4 performs the toner deterioration index calculation process to calculate the toner deterioration index ε by the above formulas (1) to (3), and the toner deterioration is performed. The index ε is recorded in the memory 34.

Subsequently, the notification processing unit Pr6 performs notification processing, creates a message to be displayed on the display panel 38, that is, a notification message, forms a message display screen on the display panel 38, and displays the message display screen on the message display screen.
"Please change the toner discarding mode in the adjustment menu of [DV Roller Cleaning] if you want to reduce the amount of toner consumption by allowing reduction in print quality."
While displaying the adjustment menu of [DV roller cleaning] for changing the print duty threshold value α as shown in FIG.

  In the adjustment menu, [AUTO], [Quality priority], [Life priority 1] and [Life priority 2] are displayed as the toner waste mode, and the toner waste mode currently selected among them is shown in FIG. The toner discarding mode of [AUTO] is highlighted by a white mark or the like. In the toner discarding mode of [AUTO], the variable m representing the addition value Δα of the print duty threshold α is set to +100 or 0 depending on whether the toner save mode is set, and the toner discarding mode of [quality priority] is In the toner discarding mode of [Life Priority 1], the variable m is set to 0, and the variable m is larger than the variable m representing the addition value Δα of the print duty threshold α in the toner discarding mode of [Quality priority]. , And in the toner discarding mode of [Life Priority 2], the variable m is set to +100, which is larger than the variable m representing the added value Δα of the print duty threshold α in the toner discarding mode of [Life Priority 1]. Ru.

  Then, when the control unit 33 receives no print data from the host computer and there is no print request from the host computer, the control unit 33 selects the toner discarding mode of the adjustment menu by the operator, and the first operation member Whether or not there is a change request of the toner discarding mode by the operator based on the notification processing is determined depending on whether the data representing the toner discarding mode is sent from the touch panel 36 as the. When data representing the toner discarding mode is sent from the touch panel 36 and there is a request for changing the toner discarding mode, the toner discarding mode setting unit Pr11 performs toner discarding mode setting processing, and when there is no request for changing the toner discarding mode, the controller 33 ends the process.

  In the toner discarding mode setting process, the toner discarding mode setting unit Pr11 acquires the toner discarding mode selected in the adjustment menu by the operator based on the data representing the toner discarding mode, and from the memory 34 for each toner discarding mode. Read out the toner discard mode set value Mdi.

  Then, the toner discarding mode setting unit Pr11 determines whether or not the toner discarding mode of [AUTO] is selected, and when the toner discarding mode of [AUTO] is selected, the toner discarding mode setting value Mdi is selected. Load the toner discard mode set value Mdi for the toner discard mode in [AUTO], and set the toner discard mode in [AUTO]. Subsequently, the toner discard mode setting unit Pr11 determines whether or not the toner save mode is set, and when the toner save mode is set, the processing for discarding the deteriorated toner and the toner save function are interlocked, and the variable Set m to +100.

  On the other hand, when the toner save mode is not set, the toner discard mode setting unit Pr11 sets the variable m to zero.

  Then, if the toner discarding mode of [AUTO] is not selected, the toner discarding mode setting unit Pr11 determines whether the toner discarding mode of [quality priority] is selected, and the toner discarding mode of [quality priority] is selected. When is selected, the toner discard mode set value Mdi for the toner discard mode of [Quality priority] among the toner discard mode set value Mdi is read, and the toner discard mode of [Quality priority] is set, and the above-mentioned variable Set m to 0.

  On the other hand, when the toner discarding mode of [Quality priority] is not selected, the toner discarding mode setting unit Pr11 determines whether the toner discarding mode of [Life priority 1] is selected, and the [Life priority 1] of When the toner discarding mode is selected, the toner discarding mode set value Mdi for the toner discarding mode of [Life Priority 1] of the toner discarding mode set value Mdi is read, and the toner discarding mode of [Life Priority 1] is set At the same time, the variable m is set to +5.

  Then, when the toner discarding mode of [Life Priority 1] is not selected, the toner discarding mode setting unit Pr11 sets the toner discarding mode for the toner discarding mode of [Life Priority 2] of the toner discarding mode set value Mdi. The value Mdi is read, the toner discarding mode of [lifetime priority 2] is set, and the variable m is set to +100.

  Subsequently, the toner discard mode setting unit Pr11 sets (updates) the print duty threshold α by adding the addition value Δα according to the variable m to the print duty threshold α, and sets the set print duty threshold α to the memory 34. Record.

  As described above, in the present embodiment, when the toner discarding mode of [AUTO] is selected and the toner save mode is set, the variable m representing the addition value Δα of the print duty threshold α is set to +100. , Disposal of toner is not always performed. Therefore, the amount of toner consumption can be suppressed.

  When the toner discarding mode of [AUTO] is selected and the toner save mode is not set, or when the toner discarding mode of [quality priority] is selected, a variable m representing the addition value Δα of the print duty threshold value α Is set to 0, the toner is disposed of. Therefore, print quality can be improved.

  Then, when the toner discarding mode of [Life Priority 1] is selected, the variable m representing the addition value Δα of the print duty threshold value α is set to +5, and the print duty threshold value α is slightly increased. The amount of degraded toner to be discarded can be reduced. Therefore, the amount of consumption of toner can be suppressed, and deterioration in print quality can be prevented.

  In addition, when the toner discarding mode of [Life Priority 2] is selected, the variable m representing the addition value Δα of the print duty threshold α is set to +100 and the print duty threshold α is increased. It will not be done. Therefore, the amount of toner consumption can be suppressed.

  As described above, in the present embodiment, it is determined whether it is necessary to perform the toner discarding process depending on whether the toner deterioration index ε is larger than the deterioration index threshold, and it is determined that the toner discarding process needs to be performed. In this case, the toner discarding process is executed, the toner discarding mode is set according to the discarded toner discarding amount, and the printing is performed based on whether the set toner discarding mode and the toner save mode are set. The duty threshold α is set.

  Therefore, when printing is often performed at a low printing duty, the toner consumption amount can be suppressed by setting the printing duty threshold value α in accordance with the discarded toner amount. As a result, the consumption of toner does not increase unnecessarily.

  In addition, when the toner save function is used, it is possible to suppress the consumption amount of toner.

Next, the flowchart of FIG. 13 will be described.
Step S11 The controller 33 determines whether there is a print request from the host computer. If there is a print request from the host computer, the process proceeds to step S12. If there is no print request from the host computer, the process proceeds to step S17.
Step S12 The print processing unit Pr1 performs print processing.
Step S13 Discarding process necessity determination section Pr2 performs a discarding process necessity determination process.
Step S14 The discarding process execution unit Pr3 performs a discarding process execution process.
Step S15 The toner deterioration index calculation unit Pr4 performs toner deterioration index calculation processing.
Step S16 The notification processing unit Pr6 performs notification processing, and ends the processing.
Step S17 The controller 33 determines whether there is a change request for the toner discarding mode. If there is a request for changing the toner discarding mode, the process proceeds to step S18. If there is no request for changing the toner discarding mode, the process ends.
Step S18 The toner discarding mode setting unit Pr11 performs toner discarding mode setting processing, and ends the processing.

Next, the flowcharts of FIGS. 14 and 15 will be described.
Step S18-1 The toner discarding mode setting unit Pr11 reads the toner discarding mode set value Mdi.
Step S18-2 The toner discarding mode setting unit Pr11 determines whether the toner discarding mode of [AUTO] is selected. If the toner discarding mode of [AUTO] is selected, the process proceeds to step S18-3. If the toner discarding mode of [AUTO] is not selected, the process proceeds to step S18-4.
Step S18-3 The toner discarding mode setting unit Pr11 sets the toner discarding mode of [AUTO].
Step S18-4 The toner discarding mode setting unit Pr11 determines whether the toner discarding mode of “quality priority” is selected. If the toner discarding mode of "quality priority" is selected, the process proceeds to step S18-8. If the toner discarding mode of "quality priority" is not selected, the process proceeds to step S18-9.
Step S18-5 The toner discard mode setting unit Pr11 determines whether the toner save mode is set. If the toner save mode is set, the process proceeds to step S18-6. If the toner save mode is not set. The process proceeds to step S18-7.
Step S18-6 The toner discarding mode setting unit Pr11 sets the variable m to +100.
Step S18-7 The toner discarding mode setting unit Pr11 sets the variable m to zero.
Step S18-8 The toner discarding mode setting unit Pr11 sets the toner discarding mode of “quality priority”.
Step S18-9 The toner discarding mode setting unit Pr11 determines whether the toner discarding mode of [Life Priority 1] is selected. If the toner discarding mode of [Life Priority 1] is selected, the process proceeds to Step S18-10. If the toner discarding mode of [Life Priority 1] is not selected, the process proceeds to Step S18-12.
Step S18-10 The toner discarding mode setting unit Pr11 sets the toner discarding mode of [Life Priority 1].
Step S18-11 The toner discarding mode setting unit Pr11 sets the variable m to +5.
Step S18-12 The toner discarding mode setting unit Pr11 sets the toner discarding mode of [Life Priority 2].
Step S18-13 The toner discarding mode setting unit Pr11 sets the variable m to +100.
Step S18-14 The toner discarding mode setting unit Pr11 adds the addition value Δα according to the variable m to the printing duty threshold value α.
Step S18-15 The toner discarding mode setting unit Pr11 records the print duty threshold α in the memory 34, and the process returns.

  In each of the above embodiments, the notification processing unit Pr6 displays a notification message prompting the operator to change the print duty threshold α on the display panel 38. However, the medium such as a sheet or a label dedicated to notification You can also print a notification message on. Furthermore, the notification message can be highlighted and printed with white nuki characters.

  In each of the embodiments, the notification processing unit Pr6 determines that the print count value ct is 100 or more and the unit discard amount ΔQ is larger than the notification necessity determination threshold β in the notification necessity determination process. If the second notification requirement is satisfied, it is determined that notification is necessary. However, the waste amount of deteriorated toner is physically detected by a sensor or the like, and the print count value ct is 100 or more. If the detected amount of discarded deteriorated toner is larger than the threshold value, it may be determined that notification is necessary.

  Furthermore, in each of the above embodiments, the notification necessity determination threshold value β is set in advance and never changed, but the notification necessity determination threshold value β may be a variable that can be changed by the operator. it can.

  In each of the above-described embodiments, the notification processing unit Pr6 is configured to perform the notification necessity determination process. However, the aggregation server connected to the printer 10 via the network collects the discarded toner amount. The notification necessity determination process may be performed. In that case, the notification process is performed by transmitting a notification message from the aggregation server to the printer 10 by e-mail.

  In each of the above embodiments, the notification processing unit Pr6 is configured to perform notification processing when the discard processing necessity determination processing by the discard processing necessity determination unit Pr2 is performed. It can also be done.

  Although the printer 10 is described in each of the above embodiments, the present invention can be applied to an image forming apparatus such as a copying machine, a facsimile machine, or a multifunction machine.

  In each of the above embodiments, a monochrome printer is described, but the present invention can be applied to a color printer.

  The present invention is not limited to the above-described embodiments, and can be variously modified based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

10 Printer 11 Photosensitive drum P P Paper Pr1 Print processing part Pr2 Disposal processing necessity determination part Pr3 Disposal processing execution part Pr4 Toner deterioration index calculation part Pr5 Print duty threshold setting part α Print duty threshold value ε Toner deterioration index

Claims (10)

(A) A print processing unit that forms an image on a medium and prints by forming a developer image on an image carrier, transferring the developer image to the medium, and fixing the image.
(B) It is determined whether printing is performed at a high printing duty or at a low printing duty, with the developer deterioration index ε indicating the deterioration state of the developer when printing is performed at a predetermined printing duty A developer deterioration index calculation unit that calculates based on a print duty threshold value for
(C) A discard processing necessity determination unit that determines whether it is necessary to perform developer discard processing depending on whether the developer deterioration index is greater than the deterioration index threshold value,
(D) a disposal processing execution unit that executes developer disposal processing when it is determined that developer disposal processing needs to be performed;
(E) An image forming apparatus comprising: a print duty threshold setting unit configured to set the print duty threshold in accordance with the amount of waste of the deteriorated developer.   The image forming apparatus according to claim 1, wherein the waste processing execution unit performs developer waste processing by forming a waste developer image on an image carrier and removing the waste developer image.   The image forming apparatus according to claim 1, further comprising a notification processing unit that performs notification processing to prompt the operator to suppress the consumption of the developer when the amount of discarded developer is large.   The image forming apparatus according to claim 3, wherein the notification processing unit calculates a discard amount of the deteriorated developer discarded in the developer discarding process, and performs the notification process based on the discarded amount of the deteriorated developer.   The image forming apparatus according to claim 3, wherein the print duty threshold setting unit sets the print duty threshold when there is a change request of the print duty threshold by the operator based on the notification by the notification processing unit.   The developer deterioration index calculation unit calculates an increase or decrease representing a difference between a reference printing load representing a printing load when printing is performed using a printing duty threshold and a printing load when printing is performed using a predetermined printing duty. The image forming apparatus according to claim 1, wherein the developer deterioration index is calculated by adding an increase or decrease to the current developer deterioration index. (A) A print processing unit that forms an image on a medium in the normal mode and a toner save mode and prints by forming a developer image on an image carrier, transferring the developer image to the medium, and fixing the image.
(B) In order to determine whether the developer deterioration index indicating the deterioration state of the developer when printing is performed at a predetermined printing duty is to be performed at a high printing duty or at a low printing duty A developer deterioration index calculating unit that calculates based on the print duty threshold value of
(C) A discard processing necessity determination unit that determines whether it is necessary to perform developer discard processing depending on whether the developer deterioration index is greater than the deterioration index threshold value,
(D) a disposal processing execution unit that executes developer disposal processing when it is determined that developer disposal processing needs to be performed;
(E) A developer discard mode is set according to the amount of discarded developer and the print duty threshold is set based on whether the set developer discard mode and the toner save mode are set. An image forming apparatus comprising: a discard mode setting unit.   The image forming apparatus according to claim 7, wherein the developer discarding mode setting unit adds a predetermined addition value to the developer deterioration index when the toner save mode is set. (A) A developer image is formed on an image carrier, the developer image is transferred to a medium, and fixed, thereby forming an image on the medium and printing.
(B) In order to determine whether the developer deterioration index indicating the deterioration state of the developer when printing is performed at a predetermined printing duty is to be performed at a high printing duty or at a low printing duty Calculated based on the print duty threshold of
(C) It is judged whether it is necessary to carry out the developer disposal processing depending on whether the developer deterioration index is larger than the deterioration index threshold value,
(D) When it is determined that the developer disposal process needs to be performed, the developer disposal process is performed,
(E) A developer consumption suppressing method, wherein the printing duty threshold value is set according to the amount of waste of the deteriorated developer. (A) A developer image is formed on the image carrier, the developer image is transferred to the medium, and fixed, thereby forming an image on the medium and printing in the normal mode and the toner save mode,
(B) In order to determine whether the developer deterioration index indicating the deterioration state of the developer when printing is performed at a predetermined printing duty is to be performed at a high printing duty or at a low printing duty Calculated based on the print duty threshold of
(C) It is judged whether it is necessary to carry out the developer disposal processing depending on whether the developer deterioration index is larger than the deterioration index threshold value,
(D) When it is determined that the developer disposal process needs to be performed, the developer disposal process is performed,
(E) setting the developer discarding mode according to the amount of discarded developer, and setting the print duty threshold based on whether the set developer discarding mode and the toner save mode are set. The developer consumption suppression method characterized by the above.

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