JPH1010855A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the dirt of a printed picture derived from toner heaping or the like on a developing roll at the time of consecutive extra fine imaging provided with a little number of dots. SOLUTION: As for this device, on detecting the extra fine imaging by the extra fine imaging decision part 31, a dummy image is produced by the dummy image producing part 15. The decision by the extra fine imaging decision part 31 is executed when the printing number decision part 0 decides the number of printing reaches a specific amount or at the time of the inter image. The toner image of the dummy image formed on a photoreceptor is removed by a cleaner device however preferably, transferred on a recording paper in order to reduce the load of cleaner device. A paper haul processing part 34 executes the paper haul demand in order to draw out the recording paper for the dummy image transfer. The dummy image may be formed to the extent of the specified number however preferably, the number of deficient dots corresponding to the reference image coverage calculated by the number of deficient dots calculating part 33 may be turned to the dummy image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus configured to transfer a toner image formed on an image carrier, that is, a photoreceptor, to a sheet material such as a recording sheet, and more particularly, to a method for forming a sheet material using toner. The present invention relates to an image forming apparatus suitable for preventing contamination.

[0002]

2. Description of the Related Art FIG. 8 is a sectional view showing an example of a developing device of an image forming apparatus. In FIG. 1, a cylindrical photoconductor 1 is rotatably supported by a housing (not shown) of the image forming apparatus, and is rotated at a predetermined speed in a direction of an arrow A by a drive source (not shown). The photoconductor 1 is provided around the photoconductor 1.
There are provided a charger for uniformly charging the surface layer of the photoconductor, an exposure device as an image writing unit, and a transfer device.
Here, illustration is omitted because no particular explanation is required. A developing device 2 for developing the electrostatic latent image formed on the photoreceptor 1 by the exposure device with toner is provided at a subsequent stage of the exposure device.

The developing device 2 includes a developing roll 3, a transport roll 4,
It has a group of rolls such as a stirring roll 5, which are arranged in a casing 6. The casing 6 contains a developer including a toner and a carrier. The developer is agitated by the agitating roll 5, and then is closest to the photoreceptor 1 by a paddle (surrounding blade member) of the transport roll 4. The developer is conveyed to the developing roll 3 located at the position. The member 7 is a regulating plate for keeping the thickness of the developer adhered to the developing roll 3, that is, the so-called spikes constant.

When the toner is gradually consumed, the toner concentration of the developer decreases. Therefore, the toner supply device 8 disposed above the stirring roll 5 removes only the toner corresponding to the consumption from a toner tank (not shown). Replenish as appropriate.
The toner supply device 8 causes the upper toner to fall onto the lower stirring roll 5 by the rotation of the supply roll 8a, and the driving of the toner supply device 8 is controlled so as to maintain the toner concentration constant. For example, in the toner supply control method disclosed in Japanese Patent Application Laid-Open No. H5-40408, the number of dots of an image to be printed is counted, and the toner density is controlled to be constant based on the number of dots. Then, on the assumption that the toner consumption is proportional to the number of dots,
The toner consumption is recognized based on the number of dots. That is, when the number of dots exceeds a predetermined reference value, it is determined that the toner consumption has reached a predetermined value, and new toner is supplied to prevent a decrease in image density.

[0005]

The image forming apparatus employing the above-described toner supply control method has the following problems. In the above-described control method, when an image having a very small number of dots (minimum imaging) is continuously formed in a large number, the number of dots does not exceed the threshold value so that the correction of the detected toner density based on the number of dots can be accurately performed. As a result, the number of times of toner supply is reduced. Further, toner consumption is small for minimal imaging. In other words, the idling state continues for a long time, and the developer is
The stirring and transport are repeated by the transport roll 4 and the transport roll 4. As a result, the particle size of the toner may deviate from an appropriate value and become extremely fine.

[0006] Toner deviating from the proper value is liable to adhere to minute flaws of the developing roll, which may cause a decrease in developing bias. For example, the developing bias, which is usually about 200 V, becomes extremely low, approaches the background potential, and the potential difference from the developing potential of the photoconductor 1 becomes larger than a predetermined value. In this case, there is a problem in that the toner adheres to a portion other than the portion where the electrostatic latent image is formed, and the printed image is contaminated as a result.

FIG. 8 shows an example in which only one developing unit 2 is provided. However, in an apparatus in which a plurality of developing units 2 are arranged to enable multi-color printing, in particular, only data marks, logo marks and the like are colored. In the case of printing, minimal imaging using only data marks, logo marks, and the like is continuous. In particular, in such a case, toner is not newly replenished because the amount of consumed toner is small, the residence time in the developing device 2 is prolonged, and the developer is likely to deteriorate.

The present invention solves the above-mentioned problems, and prevents deterioration of the developer in the case where minimal imaging is continued, thereby preventing the stain on a printed image. The purpose is to provide.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and achieve the object, the present invention provides a counting means for counting the amount of print data, wherein the counted amount of print data is smaller than a threshold value. When the print data is small, the minimal imaging determining means for determining that the imaging is minimal imaging, and a dummy image is created in response to the minimal imaging determination output by the minimal imaging determining means, and the print data of the dummy image is formed as an inter image. And a dummy image generating means for outputting the image data to the image writing means. Further, the present invention has a second feature in that the present invention is provided with a print number detecting means, wherein the minimum imaging determining means makes a determination every predetermined number of prints. Further, the present invention includes an insufficient data amount calculating unit that calculates a difference between the amount of print data counted by the counting unit and a standard print data amount as an insufficient data amount, wherein the dummy image creating unit includes an The third feature is that a dummy image corresponding to the insufficient data amount is created and output.

The present invention further comprises a recording paper feeding means, and a paper hole requesting means for requesting a paper hole from the print data generating means for generating print data. A fourth feature is that when a printing error occurs, the recording paper is pulled out from the recording paper feeding means and a dummy image is printed.

The present invention further comprises an insufficient data amount calculating means for calculating a difference between the amount of print data counted by the counting means and a standard print data amount as an insufficient data amount, wherein the dummy image creating means is provided. The fifth feature lies in that a dummy image corresponding to the insufficient data amount is created.

According to another aspect of the present invention, there is provided an image forming apparatus having an operation mode for discharging a recording sheet remaining on a recording sheet conveying path upon recovery from occurrence of an abnormality. A shortage data amount calculation unit that calculates a difference between the amount and the standard print data amount as a shortage data amount, wherein the dummy image creation unit is configured to create a dummy image corresponding to the shortage data amount. A sixth feature is that when the operation mode is generated, the dummy image generating means is activated to print the dummy image on the recording paper remaining on the conveyance path.

According to the first to seventh features, when the print data is determined to be minimal imaging, a dummy image is formed, and the count value of the counting means is increased by the print data amount of the dummy image. Therefore, the toner is consumed by the creation of the dummy image, and the count value of the counting means, which is a reference for toner replenishment, is also increased to replenish the toner. In particular, according to the fourth to sixth features, the dummy image is printed on recording paper.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 2 is a block diagram showing a main configuration of the image forming apparatus according to the embodiment of the present invention. In FIG. 1, the image forming apparatus has an image creating unit 9 and a printing unit 10. The image creating section 9 is a print data creating section 1 for creating print data printable by the printing section 10 based on image creating information supplied from a host device such as a host computer.
One. Further, it has a print data transmitting section 12 for transmitting the print data to the printing section 10. Print data creation unit 1
1 and the print data transmission unit 12 are connected to a microcomputer (C
PU) 13.

The printing unit 10 includes a print number counter 1.
4, dummy image creation unit 15, dot counter 16,
An exposure unit 17, a development unit 2, and a print data receiving unit 18 are provided. These components are controlled by a CPU 19. The dummy image is a photoconductor 1 in the inter image.
This is pseudo print data formed above, and in the present embodiment, is not formed for obtaining a printed image as information, but formed for consumption of toner. The dummy image is based on image data or numerical data for the dummy image stored in the ROM of the CPU 13, and the like.
It is generated by controlling the optical system of the exposure unit 17. In addition,
The inter-image refers to an inter-page area of a plurality of pages of an image formed on the photoconductor 1.

The print data receiving section 18 is connected to the print data transmitting section 12 by a serial communication line, and has a serial transmission interface with each other. Print counter 1
4 can be realized by the counter the counter value C _p is up by the passage of sensors disposed in the transport path of the recording paper.
On the other hand, the dot counter 16 stores the print data receiving unit 1.
The image portion, that black and white image of the data received by 8 can be realized by a counter which counter value C _d is up when receiving the reception data representing the black part (dots).

[0017] The dot counter 16 count C _d is a predetermined value (here, 1024K dots) outputs a count-up signal upon reaching. Count-up signal is read by the CPU 19, where executed are composed image information amount counter by software (hereinafter, referred to as "image counter") increments the counter value C _i of. The reason why the count-up signal of the dot counter 16 is counted by the image counter is that it is not easy to directly process this by software because the counting for each dot is very fast. is there.

The dot counter 16 also counts the number of dots in the dummy image created by the dummy image creating section 15. The dummy image creating unit 15 creates a dummy image for forcibly consuming the deteriorated toner in the developing device 2, and generates print data in accordance with predetermined dummy image information. As the image forming apparatus, the count up number of the dot counter 16
That counter value C _i, it is judged that the toner when a threshold is exceeded I _TH is a predetermined amount consumed assume apparatus for performing the toner replenishment.

FIG. 3 shows the image forming section 9 and the printing section 1.
FIG. 2 is a system diagram of the image forming apparatus that includes 0. In the figure,
Around the photoreceptor 1, a charger 20, an exposure unit 17, a developing unit 2, a transfer unit 21, and a cleaner device 22 are arranged. The developing device 2 can be configured in the same manner as that shown in FIG.
A laser beam is exposed on the photoreceptor 1 charged by the charger 20 by the exposure device 17 to form an electrostatic latent image. The laser light is modulated according to the print data supplied from the image creating section 9 and the dummy image creating section 15. The electrostatic latent image is developed with toner in a developing device 2, and the toner image is transferred to a transfer device 21.
Is transferred onto the recording paper P fed to the position of the desired print image.

The recording paper is stacked on a paper feed tray 23, and is fed from there to a transfer unit 21 via a transport path 24. A so-called registration sensor (not shown) for detecting the recording paper P and obtaining the write timing of the exposure unit 17 is provided upstream of the transfer unit 21 on the transport path 24. The registration sensor can be constituted by an actuator-type sensor that is mechanically urged by contacting the recording sheet P, or a non-contact-type sensor that detects the presence or absence of the recording sheet by reflection of light.

The toner image transferred to the recording paper P is heat-fixed by passing the recording paper P through the fixing device 25. Normally printed images are output to the output tray 26.
Is discharged. On the other hand, the recording paper that has not been printed normally is discharged to the purge tray 27. For example, at the time of restart after interruption due to a recording paper jam or the like during printing, a process is performed in which all the recording paper remaining in the transport path 24 at the time of stoppage is discharged to the purge tray 27.

A plurality of paper feed trays 23 can be provided.
The recording paper can be selectively pulled out from any of the paper feed trays. The discharge of the recording paper to the purge tray 27, that is, the purging process, is provided immediately before the discharge tray 26 with a conveyance path switching means switched by a solenoid, for example, and the recording paper is guided to the purge tray 27 by switching the conveyance path switching means. Done by

Next, an operation for preventing toner contamination in the image forming apparatus having the above configuration will be described. Generally, parameters required for controlling the image forming apparatus are determined based on the number of dots of one page of A4 size. 300 SPI (1
In an image forming apparatus of (scanning line density per inch), the number of dots per page of A4 size is 8700K dots. Therefore, when 50 standard images (870K dots) having a dot occupation ratio (image coverage) of 10% are printed, the dot counter 16 outputs 102 images.
Counter value C _i of the image counter for counting the count-up signal for each 4K dot is "42". In the present embodiment, the counter value C _i of the image counter for every 50 sheets is used.
Is less than or equal to "4", the image is determined to be an image of minimal imaging, and a process for preventing toner contamination is performed.

FIG. 4 is a flowchart showing a print data output process using a dummy image for preventing toner contamination. The following flowchart shows the processing of the CPU 19 of the printing unit 10. Also, the output processing of the original print data which is not a dummy image is executed by another routine. In the figure, reads the counter value C _p in step S1 print number counter 14, the reference number n for the number of prints is determined whether extremely small imaging (here, n = 50) whether or not reached to decide. If n prints has ended the process proceeds to step S2, the image counter counter value C _i is the threshold value I
It is determined whether or not _TH (here, I _TH = 4) has been reached. If this determination is affirmative, it is determined that not the very small imaging, clears the counter value C _p of the print number counter 14 proceeds to step S3, and the counter value C _i has reached the threshold I _TH the toner was also supplemented by the counter value C _d of the image counter counter values C _i and the dot counter 16 also clears the process proceeds to step S1.

If the determination in step S2 is negative, it is determined that the imaging is minimal imaging, so that a dummy image is formed from inter-images (between prints). wait. The inter image is determined based on a page end signal from the image creating unit 9. When the inter-image is obtained, the process proceeds to step S5, and print data of the dummy image is output to the exposure unit 17. The print data of the dummy image is such that a plurality of electrostatic latent images of lines having a width of, for example, 2 to 3 mm are formed at intervals of 2 to 3 mm over the entire axial direction of the photoconductor 1.

[0026] In step S6, adds the number of dots dummy image content of the counter value C _d of the dot counter 16. In step S7, the added dot counter 16
Counter value C of the image counter based on the counter value of
It is determined whether or not _i has reached the threshold value I _TH . The output of the print data of the dummy image, if the counter value C _i has reached the threshold I _TH determined in step S7 becomes positive, the counter value C _p proceeds to step S3,
Proceeds to step S1 clears the counter value C _d and the counter value C _i. If the counter value C _i by the output of the print data of the dummy image does not reach the threshold I _TH, the following inter proceeds to step S4 - waiting for images, in the next inter-image, the print data again dummy image Is output to the exposure unit 17.

As described above, in the first embodiment, if it is determined that the minimal imaging is performed based on the number of dots of the print data supplied from the image forming unit 9, a dummy image is formed and the dummy image is formed on the developing roll of the developing unit 2. thereby discharging the toner adhering by adhering to the photosensitive member 1 increases the count value C _d of the dot counter 16. As a result, the deteriorated toner is decreased is used, the counter value C _i because exceeds the threshold I _TH, toner is newly supplied.

If a large number of dummy images are printed at one time, the toner image of the dummy image is scraped off at once by the cleaner device 22, so that the load on the cleaner device 22 may be too large. That is, if a large amount of toner is scraped off by the toner scraping blade of the cleaner device 22, the toner may overflow from the receiving member. Therefore, the number of the plurality of lines formed as the dummy image is preferably set to be small if the capability is small, considering the capability of the cleaner device 22. If the number of lines formed at one time as a dummy image is reduced, the number of repetitions of the processing of steps S4 to S7 is increased as a result, but the load on the cleaner device 22 is reduced.

Next, a second embodiment will be described.
In the first embodiment, it is assumed that the number of print data of the dummy image is set in advance. on the other hand,
In the second embodiment, by comparing the number of dot images of the counter value C _d and standard image coverage of the dot number, that the dot counter 16, once the dummy image for the number of dots corresponding to the difference Is formed by the inter-image.

In FIG. 5, in step S10, the process waits for an inter image. If inter-image has been detected, the process proceeds to step S11, the counter value C _i of the image counter is determined whether the reached threshold I _TH. Counter value C _i is the threshold I This determination
It has reached _TH, that is, if it is determined not to be a very small imaging process proceeds to step S12, the process proceeds to step S10 to clear the counter value C _d and the counter value C _i. On the other hand, if the determination is negative in step S11, since it is very small imaging process proceeds to step S13, the number of dot counter value C _d of the dot counter 16 at that time corresponds to a standard image coverage (for example, 10%) D
Calculate how much is missing from _S. That is, the number D _L of insufficient dots is obtained. In step S14, a dummy image corresponding to the number D _{L of} insufficient dots is output to the exposure device 17.

As described above, in the second embodiment, a dummy image is formed so as to compensate for the number D _L of missing dots in each inter image. When the correction is performed for each inter image in this manner, the number of dots in one dummy image does not increase so much, and the load on the cleaner device 22 is reduced. Of course, in consideration of the capability of the cleaner device 22, a dummy image may be formed, for example, every other inter-image. The point is that the size of the dummy image may be determined in accordance with the number of missing dots, instead of setting the size of the dummy image in advance.

[0032] In addition, the number of dots D _S is not necessarily be adjusted to the standard image coverage, at least,
The number of standard dots may be set in accordance with the image coverage to the extent that the printed image is not stained due to toner deterioration. This can be determined experimentally.

Next, a third embodiment will be described.
In the above-described first and second embodiments, the dummy image formed on the photoconductor 1 is finally scraped off by the cleaner device 22, so that the load on the cleaner device 22 may be excessive. It has also been explained that this problem can be solved by reducing the number of dummy images created at one time. On the other hand, in the third embodiment, the dummy image is transferred onto the recording paper. This prevents the load on the cleaner device 22 from becoming excessive.

[0034] In FIG. 6, step reads the counter value C _p step S20 the print number counter 14, the number of prints is determined whether reaches the reference number n for determining whether a very small imaging. If n prints has ended the process proceeds to step S21, the counter value C _i of the image counter is determined whether the reached threshold I _TH.

If it is not determined that the imaging is extremely small, the process proceeds to step S22, where the print number counter 14
Counter value C _p , counter value C _d and counter value C
Clear _i and proceed to step S20. On the other hand, if it is determined in step S21 that the imaging is minimal, the process proceeds to step S23, and a paper hole request is made.
That is, the printing unit 10 requests print data from the image creation unit 9 every time one page is printed. In this request, for example, if print data of “page number 0” is requested as a paper hole request, The unit 9 stops supplying print data for one page. That is,
By stopping the supply of the print data, a blank (paper hole) for one page can be formed on the photoreceptor 1 when printing a plurality of sheets continuously. Further, the supply stop of the print data can also be realized by a recording paper feed request of “page number 0”.

If it is determined in step S24 that a signal for executing a paper hole has been transmitted from the image creating section 9, the flow advances to step S25 to pull out the recording paper for printing the dummy image from the paper feed tray 23. At this time, if not only the paper feed tray 23 but also a plurality of paper feed trays are provided, one of them is used to store the used recording paper on one side, so that the recording paper can be printed as a dummy image. Can be pulled out for use. Further, the used recording paper discharged and accumulated in the purge tray 27 is transferred to the transport path 24 upstream of the transfer device 21.
To print the dummy image. Transfer unit 2 transfers used recording paper through recording paper return path.
An image forming apparatus which is returned to the conveyance path immediately before 1 and reused is disclosed in, for example, Japanese Patent Application No. 8-8 / 1996 filed by the present applicant.
No. 4586 and Japanese Patent Application Laid-Open No. 1-122856.

In step S26, the print data of the dummy image is output to the exposure device 17. At this time, the number of dots of the dummy image to be output may be a predetermined number, or as shown in the second embodiment, the print data of the dummy image corresponding to the number of missing dots D _L is output. You may do so. If the print data of the dummy image has been output to the exposure device 17, the process of step S22 is performed, and the process proceeds to step S20.

Next, a fourth embodiment will be described.
It is known that, in an image forming apparatus, when an abnormality such as a recording paper jam occurs, the fixing device 25 becomes dirty with the toner unfixed recording paper sandwiched by the fixing device 25. Therefore, it is also known that, upon recovery from an abnormality, a sheet on which a toner image has not been transferred is passed through the fixing device 27 to remove stains from the sheet (for example, Japanese Patent Laid-Open No. 7-98556).

Therefore, in the fourth embodiment, in order to reduce the load on the cleaner device 22, a dummy image is formed by dispersing a plurality of inter-images as in the first or second embodiment. At the same time, in the recording paper discharge mode in which an error occurs during the printing and the recovery process is performed, the dummy image is printed intensively on the recording paper conveyed to remove the stain of the fixing device 25.

In FIG. 7, in step S30, it is determined whether or not a recording paper discharge (auto-purge) mode after occurrence of an abnormality. This determination can be made, for example, based on the state of a flag set when the recording paper discharge mode is discharged in another processing routine (not shown). If it is determined that the automatic purge mode, the process proceeds to step S31, the image counter counter value C _i is the threshold I _TH
It is determined whether or not has been reached. If it is not determined that the imaging is minimal, the process proceeds to step S32, where the counter value C _p , the counter value C _d and the counter value C _i are cleared, and the process proceeds to step S30. On the other hand, if it is determined that the imaging is extremely small, the process proceeds to step S33, and it is determined whether the discharged recording paper has passed a predetermined position upstream of the transfer unit 21. This position can be determined by the output signal of the registration sensor.

If it is determined that the recording paper has reached the predetermined position, in step S34, the number of dots of the dummy image to be printed on the recording paper is determined. This number of dots count value C _d of the dot counter 16 for the number of dots D _S corresponding to the standard image coverage
Is calculated as the number D _L of insufficient dots.

[0042] Since it is preferable to calculate the standard shortage dots based on the number of D _S dots D _L for the number that is printed by the time this calculation, the number of standard dots for one print D it is preferable to a value obtained by multiplying the number of prints C _P to _S and the standard number of dots D _S here.

In step S35, print data of the dummy image is output to the exposing device 17 by the number of dots corresponding to the calculated number D _L of insufficient dots. In step S36, it is determined whether or not the auto-purge mode has ended. If it is determined that the auto-purge mode has ended, in step S32, the counter values C _p , C _d and C _i are cleared. Proceed to step S30.

Next, a CPU for executing the above operation
The functions of the nineteen main parts will be described with reference to a block diagram. FIG.
In the image counter 28, the dot counter 16
Counting the count-up signal outputted every predetermined number of dots counted from then, the counter value C _i is the toner supply instruction unit 2
9 and the minimum imaging determination unit 31. Toner supply command unit 29 outputs a toner replenishment command to the developing device 2 when the counter value C _i has reached the reference value.

The print quantity determination unit 30 outputs to the very small imaging determination unit 31 a detection signal when the counter value C _P of the print number counter 14 reaches the n sheets. Very small imaging determination unit 31, the detection signal is input from the print count determination unit 30, depending on whether the counter value C _i of the image counter 28 reaches the threshold I _TH, the image to be printed or a very small imaging Determine whether or not.
Then, when it is determined that the imaging is the minimal imaging, the determination result is input to the dummy image creating unit 15.
The dummy image creation unit 15 outputs print data for forming a dummy image to the exposure unit 17 in response to the inter-image detection by the inter-image detection unit 32.

[0046] In the dummy image creation unit 15, providing the missing dot number calculating section 33 for the case of creating an image corresponding to the missing dot D _L. Insufficient dot number calculation unit 33 supplies to the dummy image creating unit 15 calculates the difference between the counter value C _d and the standard dot number D _S dot counter 16. When an image corresponding to the number D _L of insufficient dots is created, the detection signal of the print number determination unit 30 is unnecessary for the determination by the minimal imaging determination unit 31.

In order to form a dummy image on recording paper, a paper hole processing unit 34 is provided. When the minimal image determination signal is input from the minimal imaging determination unit 31, the paper hole processing unit 34 makes a paper hole request and outputs a response signal to the dummy image creating unit 15 and the tray driving unit 35. The dummy image creation section 15 outputs print data of the dummy image to the exposure device 17 based on the timing at which the recording paper fed from the paper feed tray passes through the registration sensor. Further, an auto-purge determining unit 36 is provided, and when the execution of the auto-purge is detected, the print data of the dummy image can be output to the exposure unit 17.

[0048]

As is apparent from the above description, according to the first to seventh aspects of the present invention, a toner image can be discharged by forming a dummy image at the time of minimal imaging printing. Can be prevented from accumulating on the toner. Therefore, it is possible to prevent contamination due to a decrease in the developing bias. In particular, according to the fourth to sixth aspects of the present invention, since the dummy image is printed not on the photosensitive member but on the recording paper, the load on the cleaner for cleaning the toner on the photosensitive member can be reduced. As a result, it is possible to prevent contamination due to scattering of toner from the cleaner device.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a main part of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a main configuration of a control device of the image forming apparatus according to the embodiment of the present invention.

FIG. 3 is a diagram illustrating a recording paper conveyance system of the image forming apparatus according to the embodiment of the present invention.

FIG. 4 is a flowchart of the first embodiment.

FIG. 5 is a flowchart of the second embodiment.

FIG. 6 is a flowchart of a third embodiment.

FIG. 7 is a flowchart of a fourth embodiment.

FIG. 8 is a cross-sectional view illustrating a configuration of a main part of the developing device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Photoreceptor, 2 ... Developing device, 3 ... Developing roll, 10
... Printing part, 14 ... Print number counter, 15 ... Dummy image creation part, 16 ... Dot counter, 17 ...
Exposure unit, 28 ... Image counter, 30 ... Print number judgment unit, 31 ... Minimum imaging judgment unit, 33 ...
Insufficient dot calculation unit

Claims (7)

[Claims] An image forming apparatus configured to replenish toner when the amount of print data reaches a reference value to adjust the density of a printed image, a counting means for counting the amount of print data, When the print data amount is smaller than a threshold value, the print data is determined to be minimal imaging; and a dummy image is generated in response to a minimal imaging determination output by the minimal imaging determination unit. And a dummy image creating means for outputting print data of the dummy image to the image writing means as an inter image. 2. The image forming apparatus according to claim 1, further comprising print number detection means, wherein the minimum imaging determination means makes a determination every predetermined number of prints. 3. An insufficient data amount calculating means for calculating a difference between the amount of print data counted by the counting means and a standard print data amount as an insufficient data amount; 3. The image forming apparatus according to claim 1, wherein a dummy image corresponding to the insufficient data amount is created and output. 4. A recording paper feeding means, and a paper hole requesting means for requesting a paper hole from a print data generating means for generating print data, wherein a paper hole is generated by the request of the paper hole requesting means. 3. The image forming apparatus according to claim 1, wherein the recording paper is pulled out from the recording paper feeding means and a dummy image is printed. 5. An insufficient data amount calculating means for calculating a difference between the amount of print data counted by said counting means and a standard print data amount as an insufficient data amount, wherein said dummy image creating means comprises: 5. The image forming apparatus according to claim 4, wherein the image forming apparatus is configured to create a dummy image corresponding to the amount. 6. An image forming apparatus having an operation mode for discharging recording paper remaining on a recording paper conveyance path at the time of recovery from occurrence of an abnormality, comprising: an amount of print data counted by said counting means; A shortage data amount calculation unit that calculates a difference in print data amount as a shortage data amount, wherein the dummy image creation unit is configured to create a dummy image for the shortage data amount, and the operation mode 3. The image forming apparatus according to claim 1, wherein when the occurrence occurs, the dummy image creating unit is energized to print the dummy image on the recording paper remaining on the conveyance path. 7. A dot counter for counting the number of print data, counting a number of dots of the print data, and outputting a count-up every time a predetermined number of dots is reached, and counting the number of times of the count-up. 7. The image forming apparatus according to claim 1, further comprising an image counter that outputs a count result as the amount of the print data.