JP2003270878A - Developing device and image forming device - Google Patents

Abstract

(57) [Summary] [Problem] To make it possible to set a consumption amount corresponding to an actual usage state of toner when forcibly consuming toner, thereby forcing forced consumption corresponding to a progress state of toner deterioration. Provided is a developing device capable of preventing occurrence of abnormal image density and background stain. SOLUTION: When the number of pixels used when forming an electrostatic latent image is equal to or less than a predetermined toner consumption amount, a forced consumption means for forcibly consuming toner corresponding to a difference from the predetermined toner consumption amount. 13, the forcible consuming means 13 comprises:
When the toner is forcibly consumed, the forcible consumption is corrected in accordance with the number of prints executed until the toner replenishment is started, and the toner corresponding to the forcible consumption after the correction is applied to the latent image carrier. It is characterized in that it is supplied to a non-image forming area.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device and an image forming apparatus, and more particularly to a structure for preventing an abnormal image from being generated due to deterioration of a developer.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a printing machine, a developing process for visualizing an electrostatic latent image formed on a latent image carrier is set. There is. In the development process, a two-component developer composed of a carrier and toner attached to the carrier or a one-component developer composed of only the toner without a carrier is used. As a developing method for supplying an image, a contact method in which a developer is brought into contact with the surface of a latent image carrier to adsorb toner by an electrostatic force between the latent image carrier and a toner is generated by an electric field action formed by a developing bias. There is a non-contact method of flying and adsorbing onto an electrostatic latent image.

In the developing process, when the charge amount of the toner and the electrostatic amount of the electrostatic latent image are balanced due to the electrostatic relationship between the electrostatic latent image and the electrostatic latent image, more toner adheres to the electrostatic latent image. Instead, it is not consumed and is collected in the developing device in a so-called unused state.

In the toner collected in the developing device,
The following problems may occur. The toner is agitated and mixed in the developing device until it is supplied to the electrostatic latent image, or the surface of the developing roller which is arranged to face the latent image carrier in the developing device and is arranged in the vicinity of this surface. It becomes charged due to friction between the blade and the blade. In particular,
In the developing method using a one-component developer, the toner layer may be formed into a uniform thin layer on the surface of the developing roller composed of a metal roller or the like, and then the toner may fly to the electrostatic latent image. In this case, the characteristics of the toner are deteriorated, particularly the charging characteristics are deteriorated due to friction between the toners generated on the surface of the developing roller or the blade for thinning, or by stirring and mixing in the conveying and stirring process. Sometimes.

Deterioration of toner characteristics, particularly deterioration of charging characteristics, is caused by an external additive contained in the developer, that is, an additive used for adjusting fluidity and triboelectric charge amount, and for improving cleaning property. It is considered that it is buried in the toner by stirring or stirring. As the external additive, fine powder of colloidal silica (SiO ₂ ), titanium oxide, alumina, fatty acid metal or the like is added to the toner surface for use.

Toner may be replenished for the purpose of optimizing the density as the developing density decreases, but unconsumed toner (hereinafter referred to as unconsumed toner) remaining in the developing apparatus when new toner is introduced into the developing apparatus. , For the sake of convenience, the residual toner is charged to the opposite polarity due to friction between the two, and when they are combined, they are attracted by the background potential of the latent image carrier and cause background stains. There is. Further, in the non-contact developing method utilizing the flying of toner, the charge amount of the residual toner increases due to friction and agitation with the lapse of time, and if it remains adsorbed on the surface of the developing roller, the flying property is impaired. As a result, it may not be possible to obtain an appropriate image density.

Conventionally, in order to prevent a decrease in image density due to toner deterioration, the printing rate is calculated for each image formation, and when the printing rate is smaller than a predetermined printing rate, in other words, the toner is When the amount of toner consumption is low and the amount of residual toner is high, a checkerboard-shaped image is obtained before the next image formation so that the amount of toner consumption can be obtained according to the printing rate, and is collected by the cleaning device without executing the transfer process. A method of forcibly consuming the toner is proposed (for example, Japanese Patent No. 029648).

[0008]

In the above-mentioned method, the amount of developer supplied is controlled by performing dummy printing by forcibly supplying the developer, regardless of the printing rate during normal image forming processing. The amount of developer consumed can be optimized.

However, the relationship between the amount of image and the amount of developer consumed depends on the mechanical gap of the developing gap, the charging device, the exposure device, etc., which affects the toner supply amount, the temperature and humidity, and the sensitivity of the latent image carrier. It often changes due to deterioration over time, and it is difficult to use a fixed relationship as a reference. Therefore, when the image amount, that is, the compulsory consumption of the printing rate at a fixed value, is not constant, the number of image formations up to the toner end, that is, the number of sheets of recording paper, and the cumulative drive time of the developing device are not constant. The degree of progress of toner deterioration changes. Therefore,
If the compulsory consumption amount is set to be large, there arises a problem that the toner yield is lowered. Moreover, in the above-mentioned proposed method, since the forced consumption operation is performed for each sheet of paper, the time required for the forced consumption operation is required for each sheet, which inevitably reduces the number of image formations, that is, the number of prints. As a result, the image forming efficiency may be reduced.

In view of the above problems in stabilizing the toner consumption amount, it is an object of the present invention to make it possible to set the consumption amount corresponding to the actual usage state of the toner when the toner is forcibly consumed. It is an object of the present invention to provide a developing device and an image forming apparatus that can perform forced consumption corresponding to the progress of deterioration to prevent the occurrence of abnormal image density and background stain due to suppression of toner deterioration. In particular, the forced consumption amount can be corrected according to the usage status of the toner based on the number of prints until the toner end is detected or the driving time of the developing device until the toner end is detected. The purpose is to make it possible.

[0011]

The invention according to claim 1 is
In a developing device that performs visible image processing of an electrostatic latent image by supplying toner carried by a developing roller to the electrostatic latent image formed on the latent image carrier, the electrostatic latent image is formed. When the number of pixels used when the toner consumption is equal to or less than the predetermined toner consumption amount, a forced consumption unit for forcibly consuming the toner corresponding to the difference from the predetermined toner consumption amount is provided, and the forced consumption unit is the toner At the time of the forced consumption of the toner, the forced consumption amount is corrected according to the number of prints executed until the start of the replenishment of the toner, and the toner corresponding to the corrected forced consumption amount is stored on the latent image carrier. It is characterized in that it is supplied to the image forming area.

According to the second aspect of the invention, the visible image processing of the electrostatic latent image is performed by supplying the toner carried by the developing roller to the electrostatic latent image formed on the latent image carrier. In the developing device, when the number of pixels used to form the electrostatic latent image is equal to or less than a predetermined toner consumption amount, the toner corresponding to the difference from the predetermined toner consumption amount is forcibly consumed and the toner is forcibly consumed. The forcible consumption means corrects the forcible consumption amount in accordance with the development drive time that is driven until the start of replenishment of the toner during the forcible consumption of the toner, and the forcible consumption amount after the correction is obtained. It is characterized in that a corresponding toner is supplied to the non-image forming area on the latent image carrier.

The invention according to claim 3 is the invention according to claim 1 or 2.
In addition to the invention described above, the toner is composed of a non-magnetic one-component toner, and the developing roller is configured to fly and supply the toner in a non-contact state with the latent image carrier. It is characterized by

An invention according to claim 4 is characterized in that the developing device according to any one of claims 1 to 3 is used for an image forming apparatus.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing an image forming apparatus in which the developing apparatus according to the present embodiment is used, and the image forming apparatus 1 shown in the figure has a configuration capable of forming a two-color image by reversal development. In FIG. 1, an image forming apparatus 1 is provided with a drum-shaped photoconductor (hereinafter, referred to as a photoconductor drum) 2 as a latent image carrier rotatably. A first image forming unit A and a second image forming unit B that perform image forming processing in the rotation process of the body drum 2, and images formed by these image forming units are recorded on recording paper fed from a paper feeding unit (not shown). A transfer device 3 for transferring and a cleaning device 4 for removing residual toner remaining on the photosensitive drum 2 are arranged.

The first image forming section A includes a first charging device A.
1, a first writing device A2 (only an optical path is shown for convenience) and a first developing device A3 are provided, and a second charging device B1 and a second writing device B2 (in the second image forming unit B). For convenience, only the optical path is shown) and a second developing device B3 is provided. In FIG. 1, reference numeral 5 indicates a charge eliminating lamp for removing residual charges on the photosensitive drum 1.

The photoconductor drum 2 has a conductive substrate on which a base layer, a charge generation layer, a charge transport layer, and the like are sequentially laminated, and a driving unit (not shown) rotates at a speed of 200 mm / sec in a fixed direction, in FIG. , It is designed to rotate clockwise.

Although not shown in detail, the first developing device A3 has a structure using a two-component developer having a well-known structure composed of a magnetic carrier and toner, and the magnetic brush developer is a photoreceptor. Photosensitive drum 2 in contact with drum 2
A developer is supplied to the electrostatic latent image formed on.

In the case of this embodiment, the second developing device B3 is
The first developing device A3 is configured to be capable of supplying the developers of different colors while not damaging the visible image formed on the photoconductor drum 2, and therefore, in a state of not being in contact with the photoconductor drum 2. A one-component non-contact developing system capable of flying a non-magnetic toner which is a one-component developer is used. The detailed structure of the second developing device B3 is shown in FIG. In FIG. 2, the second developing device B3 includes a developing roller 7 that faces the photoconductor drum 2 inside the developing housing 6, and the developing roller 7 has a peripheral surface that is a bead blasted conductor or surface. The thinning blade 8 in which the dielectric portion and the conductive portion are arranged in a minute area to form a float electrode and which is arranged in contact with the peripheral surface 8
The toner passing therethrough in cooperation with is thinned in a state of being pushed into the surface of the developing roller 7, and is triboelectrically charged between the roller surface and the blade.

Spacers 7A for setting a predetermined gap between the developing roller 7 and the surface of the photosensitive drum 2 are provided at both ends of the developing roller 7 in the axial direction. The toner is made to fly toward the photosensitive drum 2. Since the toner is a non-magnetic material and magnetic force is not used, the toner is supplied to the surface of the developing roller 7 by the supply roller 9 which is arranged in the vicinity of the developing roller 7 and contacts the peripheral surface of the developing roller 7. Has become.

The second developing device B3 is provided with a replenishing section 10 capable of supplying new toner toward the supply roller 9. Inside the replenishing section 10, an agitator 11 for frictionally charging the toner by stirring is provided. It is arranged. The replenishment unit 10 is provided with a toner end sensor 12 capable of detecting a toner end state in which the toner in the replenishment unit 10 is exhausted. The toner end sensor 12 uses a piezoelectric vibration method in this embodiment. It is said to have been configured. The toner end sensor 12 is electrically connected to the compulsory consumption means 13 described later.

FIG. 3 is a block diagram showing the configuration of a control section (hereinafter, the control section 13 is replaced with the forced consumption means) which is a main part of the toner forced consumption means. In FIG. A main part 13 is composed of a microcomputer, and a toner end sensor 12, a number counter 14 capable of counting the number of recording sheets passed, and a second developing device B3 on the input side via an I / O interface (not shown). A timer counter 15 capable of measuring the drive time of the second developing device B3, means for detecting the pixel amount as write data, and in this case, a drive section 16 of the write means are connected. Further, the operation panel 17 is connected to the input side, and the output side of the second charging device B1 and the second writing device B2 related to the image forming process using the second developing device B3 except the transfer device 3. The drive units (the second image forming unit B is shown in FIG. 3 for convenience) are respectively connected. Although not shown in detail, the operation panel 17 is capable of designating a recording paper size to be printed. When the size is input, the control unit 1 sets the recording paper length, that is, paper length data (L). Will be saved.

The control unit 13 forming the compulsory consumption means registers the pixel amount corresponding to the image formed on the photosensitive drum 2, and when the pixel amount of the image to be formed has not reached the specified amount, That is, when the amount is less than or equal to the specified pixel amount, a function is provided to forcibly consume the toner corresponding to the difference between the specified pixel amount and the pixel amount corresponding to the image formed at this stage. That is, when the pixel amount (image amount) of the image formed at the present stage is less than the prescribed pixel amount (image amount), the toner consumption amount at the present stage for the prescribed image amount is insufficient. The amount (difference) that is present is regarded as the toner that has not contributed to the development, and is forcibly consumed as the toner that does not contribute to the development and remains in the second developing device B3. This prevents the residual toner from being deteriorated due to stirring and friction. In the present embodiment, the compulsory consumption process is executed after the image forming process using the first and second image forming units A and B, that is, after the printing is completed, and in this process, the second writing device B2 causes the photoconductor drum. An image pattern for compulsory consumption is formed in the non-image forming area in 2 by a pattern such as dots, solids or lines.

FIG. 4 shows a flow chart for explaining the processing contents on the premise of the forced consumption mode in the control unit 13. In FIG. 4, when the image forming apparatus 1 is started, initialization of stored data is executed (ST1), and when a print command is executed on an operation panel (not shown) (ST2), a color image is displayed. The amount (Pi) is input from the drive unit 16 of the writing device and stored in the pixel amount counter B (ST3). The image amount (Pi) saved in step ST3 is the pixel amount Pi and the paper length L.
This value corresponds to the value at the time of printing for the target (for convenience, shows the state input in the step indicated by reference numeral ST3 ′).

When the pixel amount (Pi) and the paper length (L) are input, when the control unit 13 uses the pixel amount (Pi) to set the pixel amount corresponding to the unit paper length to P, it becomes a formation target. The image consumption amount (Pc) is calculated (ST4), and when there is a difference between the prescribed image amount (P) and the toner consumption amount (Pc) of the image to be formed ( ST5),
After the formation of the image with the difference is completed, the consumption pattern is formed for the non-image forming area of the photosensitive drum 2 (S).
T6). This consumption pattern is the second pattern except for the transfer device 3.
The image forming unit B is formed by using each device. As a result, when the amount of toner consumed in the image to be written is smaller than the specified consumption amount, the difference from the specified consumption amount is forcibly consumed, and deteriorated toner is generated in the developing device. Is suppressed. When the forced consumption of toner is completed, the image amount stored in the counter is reset from the counter B (ST7).

The above is the forced consumption mode presupposed by the control unit 13 in the present embodiment, and the forced consumption amount in the presumed forced consumption mode is corrected in accordance with the actual toner consumption state. ing. This will be described below. In the present embodiment, the control unit 13 executes the following control. (1) When the toner is forcibly consumed, the forcible consumption amount is corrected according to the number of prints executed until the toner supply is started, in other words, until the toner end is reached, and the correction is performed. The toner corresponding to the later forced consumption is supplied to the non-image forming area on the latent image carrier. (2) When the toner is forcibly consumed, the forcible consumption is corrected in accordance with the developing drive time that is driven until the toner supply is started, in other words, until the toner end is reached. The toner corresponding to the corrected compulsory consumption amount is supplied to the non-image forming area on the latent image carrier.

The control mentioned in (1) is shown in FIG. 5 and the subsequent figures, the same processing contents as those shown in FIG. 4 are designated by the same reference numerals, and the description of steps other than the necessary steps is omitted. In FIG. 5, when the print command is executed (ST2), the number counter 14 based on the command (displayed as the number counter A for convenience in FIG. 5) counts up (ST8), and the consumption amount and the specified image amount are increased. When there is a difference between and, the forced consumption is executed as in the case shown in FIG. 4 (ST6).

When the forced consumption ends, it is judged whether or not there is a signal from the toner end sensor 12 (ST9). If the toner end signal is not input, the above processing is continued and the toner end signal is input. In this case, the value of the sheet counter (counter A) 14 is read (ST
10). When the number of sheets (N) from the sheet number counter 14 is read, a value obtained by multiplying the prescribed image amount (P) used up to the toner end by the value of (N / N _STD ) is added to the new prescribed image amount (P). () Is corrected (ST11), the value of the sheet counter (counter A) 14 is cleared, the toner end sensor 12 is also reset (ST12), and the printing operation is restarted.

The above-mentioned N _STD is a specified value of the number of prints until the toner end, which is experimentally obtained. The present inventor conducted various experiments by changing the number of prints until the toner end, and obtained the results shown in FIG. FIG. 6 shows the number of prints up to the toner end and the rank of the granular stain after toner replenishment. When the number of prints of rank 4 or higher is a good image, the toner end is reached when the number is 2500.
_It is sufficient to set the _STD .

Next, the control described in (2) will be described with reference to FIG. In the flowcharts shown in FIG. 7 and subsequent figures, the same processes as those shown in FIG. 5 are designated by the same reference numerals. When the print command is executed in FIG. 7 (ST2), the driving time (T) of the developing device based on the command is integrated and stored in the timer counter 15 (in FIG. 7, represented as a driving time counter C for convenience). (S
In T13), if there is a difference between the consumption amount and the specified image amount (ST5), forced consumption is executed as in the case shown in FIG. 4 (ST6).

When the forced consumption ends, it is determined whether or not there is a signal from the toner end sensor 12 (ST9). If the toner end signal is not input, the above processing is continued and the toner end signal is input. In this case, the integrated value of the timer counter 15 (counter C) is read (ST14). When the integrated value (T) of the driving time from the timer counter 15 (counter C) is read, the specified image amount (P) used up to the toner end is compared with that in FIG.
As in the case shown in, the value related to the driving time (N /
N _STD ) is multiplied and corrected as a new prescribed image increase amount (P ′) (ST15). When the process of step ST15 ends, the integrated value of the timer counter 15 (counter C) is cleared, and the toner end sensor 12 is also reset (ST16).

In the present embodiment, the prescribed image amount (P ') newly set by correction from the preset prescribed image amount (P) is not set one by one at the time of printing for each sheet, but is set to a prescribed value. It is also possible to carry out every time the image is formed. FIG. 8 shows this case. In FIG. 8, when a print command is executed (ST2), the number-of-prints counter 14 (counter A) shown in FIG. 5 is counted up (ST8), and the timer counter 14 (shown in FIG. The cumulative time (T) of the drive time counter C) and the paper length data are loaded, and the paper length is integrated based on the number of loadings (ST1).
3, ST17 to ST18). Since the image amount (Pi) is captured in accordance with the capture of the paper length, the control unit 1
In the case of No. 3, when the specified image amount is calculated from the integrated value of both (for convenience, the specified image amount integrated is indicated by the symbol Pim),
An image amount (Pim ') corresponding to the accumulated image information (sheet length, image amount) is obtained (ST17).

At the time when the image amount (Pim ') is obtained,
When the count value from the number of sheets counter (counter A) is compared with a predetermined value (m) and reaches a predetermined value, that is, when the number of times of printing is added to the predetermined number of times, the image amount (Pi
n ′) and the sheet length (Ln), the consumption amount is calculated by the same procedure as described in FIG. 4 (ST4). When the consumption amount is smaller than the image amount in comparison with the image amount, (ST9) After the formation of the image with the difference, the consumption pattern is formed for the non-image forming area of the photosensitive drum 2 (ST6).

At the time of forming the consumption pattern, the toner end is discriminated (ST9), and the prescribed image amount (P) is set as the correction value (P ') according to the result (ST15), and the sheet number counter 14 (counter). The reset of A) and the toner end reset are respectively performed, and the image forming process is restarted (ST16).

The present inventor conducted an experiment on the number of prints up to the toner end for the case where the conventionally known forced consumption amount is fixed, as opposed to the case where the toner forced consumption amount is corrected based on the above control. Then, the results shown in FIG. 9 were obtained. FIG. 9 shows 10 ° C. as the environmental condition of the experiment.
% RH, 23 ° C 60% RH, 30 ° C 90% RH 3
The state is set. As is clear from FIG. 9, when the forced consumption amount is set to a fixed value, the number of prints changes, whereas when the above control is performed, the number of prints can be kept constant.

[0036]

According to the inventions of claims 1 and 2,
When the toner is forcibly consumed, the consumption amount corresponding to the actual usage state of the toner can be set so that the forcible consumption corresponding to the progress of the toner deterioration is performed, and the image density is abnormal due to the suppression of the toner deterioration. It is possible to prevent the occurrence of stains on the skin and the background. Particularly, in the invention described in claim 1, the forced consumption amount is corrected based on the number of prints until the toner end is detected and toner supply is started. In the invention described in claim 2, the toner end is detected. Since the forced consumption amount can be corrected based on the drive time of the developing device until the toner replenishment is started, it is a situation that actually corresponds to the occurrence of toner yield and background stain that occur when the forced consumption amount is fixed. Can be prevented. Moreover, since the correction time of the forcible consumption amount is based on the time until the toner replenishment is started, it is possible to eliminate the forcible consumption time required for each sheet and prevent the image forming efficiency from being lowered.

According to the third aspect of the present invention, the forced consumption amount can be corrected in the non-contact developing method using the one-component non-magnetic toner in which the background stain due to the flying of the toner is apt to be noticeable. It is possible to reliably prevent the deterioration and the background stain.

According to the fourth aspect of the invention, when the deterioration of the toner due to the forcible consumption is prevented, the forcible consumption amount can be set according to the actual usage state of the toner.
It is possible to prevent a decrease in image density, a background stain, and a decrease in image forming efficiency that are likely to occur when the actual consumption amount is not supported.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining a configuration of an image forming apparatus including a developing device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining one of the developing devices according to the embodiment of the present invention.

FIG. 3 is a block diagram for explaining a configuration of toner forcible consumption means for the developing device shown in FIG.

FIG. 4 is a flow chart for explaining the action at the time of forced consumption by the forced consumption means shown in FIG.

5 is a flow chart for explaining one of the actions of the forced consumption means shown in FIG.

FIG. 6 is a diagram showing an experimental result for determining the number of prints up to the toner end used to obtain the action shown in FIG.

FIG. 7 is a flow chart for explaining another operation of the forced consumption means shown in FIG.

FIG. 8 is a flowchart illustrating a case where forced consumption is executed by setting a predetermined time interval in the operation of the forced consumption means shown in FIG.

9 is a diagram showing a change in the number of printed sheets when the action of the forced consumption means shown in FIG. 3 is not used.

[Explanation of symbols]

1 Image forming device 2 Photoconductor drum that is a latent image carrier 7 developing roller 12 Toner end sensor 13 Control unit that constitutes the compulsory consumption means 14 Sheet counter 15 timer counter 16 Drive unit of writing device capable of outputting image amount A First image forming unit A3 First developing device B Second image forming unit B3 Second developing device

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Junichi Misawa             713 Tsuruga Sone, Yashio City, Saitama Prefecture F term (reference) 2H027 DA01 DA38 DA45 DB01 DD02                       DE03 DE07 DE10 EA06 EC06                       EC10 EC11 EC14 EC19 ED10                       EE02 EF09                 2H077 AD06 AD13 AD35 AE03 AE04                       DA13 DA16 DA20 DA22 DA75                       DA78 DA87 DB02 DB22 EA03                       EA14 EA15 EA16 GA14 GA17

Claims (4)

[Claims] 1. A developing device for performing visible image processing on an electrostatic latent image by supplying toner carried on a developing roller to the electrostatic latent image formed on a latent image carrier. When the number of pixels used when forming the electro-latent image is less than or equal to a predetermined toner consumption amount, a compulsory consuming unit for forcibly consuming the toner corresponding to the difference from the predetermined toner consumption amount is provided, When the toner is forcibly consumed, the consuming unit corrects the forcible consumption amount in accordance with the number of prints executed before the start of replenishment of the toner, and the toner corresponding to the after-corrected forcible consumption amount is used as the latent image. A developing device which supplies the toner to a non-image forming area on a carrier. 2. A developing device for performing visible image processing of an electrostatic latent image by supplying toner carried on a developing roller to the electrostatic latent image formed on a latent image carrier. When the number of pixels used when forming the electro-latent image is less than or equal to a predetermined toner consumption amount, a compulsory consuming unit for forcibly consuming the toner corresponding to the difference from the predetermined toner consumption amount is provided, When the toner is forcibly consumed, the consuming unit corrects the forcible consumption amount in accordance with the development drive time that is driven until the start of replenishment of the toner, and the toner corresponding to the corrected forcible consumption amount is replaced by the latent image. A developing device comprising: supplying to a non-image forming area on an image carrier. 3. The developing device according to claim 1, wherein the toner is composed of a non-magnetic one-component toner, and the developing roller is in the non-contact state with the latent image carrier. A developing device characterized in that the developing device is configured to fly and supply. 4. An image forming apparatus using the developing device according to any one of claims 1 to 3.