JPH01266565A - Image forming device - Google Patents

Abstract

PURPOSE:To effectively replenish developer by driving an information means at the time of outputting a detection signal showing that the residual of developer in 1st and 2nd developer replenishment means becomes 1st and 2nd reference amount from 1st and 2nd developer residual detection means. CONSTITUTION:The information means is driven when the detection signal showing that the developer residual in the developer replenishment means 2Y, 2M, 2C and 2BK becomes the 2nd reference amount is outputted from any one of the 2nd developer residual detection means S2y, S2m, S2c and S2bk provided in the 2nd developer replenishment means 2Y, 2M, 2C and 2BK. The information means 30Y, 30M, 30C and 30BK are driven also when the detection signal showing that the developer residual in the developer replenishment means 1Y, 1M, 1C and 1BK becomes the 1st reference amount is outputted from the 1st developer residual detection means S1y, S1m, S1c and S1bk provided in the developer replenishment means 1Y, 1M, 1C and 1BK. Thus, the developer can be effectively replenished.

Description

DETAILED DESCRIPTION OF THE INVENTION 1.1 The present invention generally relates to an image forming apparatus, and particularly relates to a recording device constituting an output section of a facsimile machine, a computer, etc., including a multicolor electrophotographic copying device equipped with a plurality of developing units. etc,
DESCRIPTION OF THE PREFERRED EMBODIMENTS In this specification regarding color image forming apparatuses such as various color printers, a multicolor electrophotographic copying apparatus will be described as a color image forming apparatus.

This type of multicolor electrophotographic copying apparatus has a structure that allows development of two colors, color copies of three or more colors, or full color copies, for example. Therefore,
The multicolor electrophotographic copying apparatus usually includes a photoreceptor drum formed with a fairly large diameter and serving as an image carrier within the main body of the apparatus;
A configuration having an image forming section including various devices including three to four developing units disposed along the outer circumferential surface of the photosensitive drum in close proximity to the outer circumferential surface of the photosensitive drum. It becomes. Each of the developing devices listed in E contains separate developers such as yellow Y, magenta M, cyan C, and black BK. This system converts the electrostatic latent image of original image information into a visible image. In the multicolor electrophotographic copying apparatus having the above-mentioned configuration, four developing units must be disposed near the outer peripheral surface of the photoreceptor drum. Compared to monochromatic electrophotographic copying machines that only require one developer installed nearby, the internal space required for installing the developer is 4.
In addition, the diameter of the photoreceptor drum must be made considerably larger than that of a monochrome copying device, so that it is possible to avoid increasing the size of the entire device and increasing costs due to the increase in size. Therefore, as a measure to avoid increasing the size of such an apparatus, a multicolor electrophotographic copying apparatus equipped with a so-called rotary developing device was proposed (Japanese Patent Publication No. 50-93437). The outline of this proposal is that a one-rotation type developing device, that is, a roughly cylindrical housing that holds four developing devices and is rotatably supported, is placed near the outer peripheral surface of the photosensitive drum. The static latent image formed on the photosensitive drum is sequentially developed by the rotation of the housing with a developing device that comes to a developing position facing the outer circumferential surface of the photosensitive drum. For details, please refer to the above-mentioned bulletin).

The conventional rotary developing device of JJI@ as mentioned above is a
The multicolor electrophotographic copying apparatus equipped with the present invention will be described in more detail below. That is, the conventional rotation: &, itJ
, in a multicolor electrophotographic copying device equipped with an image rate 4,
In the developing step of visualizing the M electrostatic latent image formed on the photoreceptor drum, the rotary developing device is configured such that when the amount of developer remaining in each of the developing devices becomes low, it can be replenished. A plurality of large-capacity hoppers capable of storing a large amount of developer are installed outside the apparatus in accordance with the number of developing units provided in the rotary developing apparatus. By installing the hopper as described above, even when a large number of copies are required, the device can be driven continuously for a long period of time, and the Even if it becomes necessary to replenish developer from each hopper, the developer can be replenished with almost no manual intervention.

-,
By the way, in the conventional multicolor electrophotographic copying apparatus described above, one toner sensor is provided as a developer remaining amount detection means for detecting the amount of developer remaining in each of the plurality of hoppers. When the sensor detects that each of the hoppers is empty, it is configured to display a predetermined warning on a display, etc. disposed in the device in order to notify a service person, a user, etc. has been done.

That is, the above-mentioned multicolor electrophotographic copying apparatus is an apparatus that employs four color developers, for example, yellow toner, magenta toner, cyan toner, and black toner, and uses these four color developers to form a multicolor image. In this case, the toner sensor is installed in each of the four hoppers that individually store developer for the four colors, and the toner sensor detects when the remaining amount of developer in each hopper is exhausted. Each display is designed to display a warning when a detection signal indicating that something has happened is output.

In the multicolor electrophotographic copying apparatus described above, for example, the yellow toner remains in an amount that reaches a position slightly higher than the level of the toner sensor in the hopper that stores the yellow toner, and If it is assumed that when the magenta toner remains in the magenta toner-dedicated hopper in an amount slightly larger than the remaining amount of the yellow toner, and the yellow toner and magenta toner are consumed in approximately the same amount, one image will be generated. During printing, a warning message indicating that the yellow toner has run out is first displayed on the display, so the drive of the copying device must be stopped and the yellow toner dedicated hopper must be refilled with yellow toner. become. However, when an operator or the like resumes driving the copying machine after replenishing the yellow toner, a warning message indicating that the magenta toner has run out appears on the display after only a few copies have been made. Therefore, it is necessary to stop the driving of the copying apparatus and replenish the magenta toner-dedicated hopper with magenta toner. - Since the above-mentioned situation can naturally be assumed for cyan toner and black toner, for example, when continuous copying work is required, the drive of the copying machine must be stopped many times to replenish toner. As a result, work efficiency becomes extremely poor.

Therefore, in view of this fact, when a detection signal indicating that the developer is running out is output from the toner sensor of the hopper storing the developer of the different colors, and the above-mentioned display displays a warning message due to this, In addition to replenishing the toner in this hopper, it was considered that other hoppers would also be refilled with toner in anticipation, but the amount of toner stored in the toner cartridge may be insufficient due to the toner in the hopper being clogged. If the volume is larger than the empty space, there is a problem in that toner overflows from the hopper, contaminating not only the copying apparatus but also the operator.

Therefore, the present invention was devised in order to improve the above-mentioned problems, and its purpose is to efficiently replenish toner to a plurality of hoppers, and to An object of the present invention is to provide an image forming apparatus in which the apparatus, an operator, and the like are not contaminated by toner when replenishing a hopper with toner.

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The above object is achieved by an image forming apparatus according to the present invention. In summary, the present invention includes an image carrier, a plurality of developing means containing a developer for visualizing an electrostatic latent image formed on the image carrier, and a plurality of developing means for each of the developing means. In the image forming apparatus, the image forming apparatus includes a plurality of developer replenishing means provided corresponding to each of the developing means for replenishing the developer. a first developer remaining amount detection means for detecting whether or not the developer remaining amount in the means has reached a preset first reference amount; a second developer remaining amount detecting means for detecting whether a second reference amount has reached a second reference amount that is smaller than the set first reference amount; A notification means is provided for notifying the developer remaining amount status in each of the developer replenishment means based on a drive command signal generated by signal processing according to the detection signal, and is provided in each of the developer replenishment means. When a detection signal indicating that the remaining amount of developer in the developer replenishing means has reached the second reference acid is output from any one of the second remaining developer amount detecting means, the notifying means At the same time, the remaining amount of developer in the developer replenishing means is determined from a first developer remaining amount detection means provided in a developer replenishing means different from the developer replenishing means. The image forming apparatus is characterized in that the notifying means is driven even when a detection signal indicating that a reference amount of 1 has been reached is output.

IL example An embodiment of the present invention will be described below with reference to one drawing.

FIG. 2 shows an image forming bag d according to an embodiment of the present invention.The outline of an image forming apparatus according to an embodiment of the present invention is as follows. That is, in FIG. 2, the image forming apparatus main body (hereinafter simply referred to as "apparatus main body")! A transfer material conveyance system I is provided in an area extending from one side of the apparatus main body 100 (right side in FIG. 2) to approximately the center of the apparatus main body lOO.
A latent image forming section II is provided at approximately the center of the image forming apparatus 0, close to the transfer drum 9 constituting the transfer material conveyance system. Furthermore, a developing means, ie, a rotary developing device Mm, is disposed in the vicinity of the latent image forming portion (3), and developer replenishing means, ie, hoppers 2Y, 2M, which will be described later, are provided in the vicinity of the rotary developing device m. A developer replenishing device 2 made of 2C12BK is provided. To explain the above-mentioned configuration in more detail, the transfer material conveyance system I includes a transfer material supply tray 101 that is detachable from an opening formed on one side (right side in FIG. 2) of the apparatus main body lOO. .102
, paper feed rollers 103 and 104 disposed approximately directly above the trays 101 and 102, and these paper feed rollers 10.
3. The paper feed guides 5a and 5b are arranged close to the paper feed roller 6 and are arranged close to the paper feed roller 6, and the paper feed guides 5a and 5b are arranged near the distribution paper guide 5b, and are arranged near the outer peripheral surface from the upstream side to the downstream side in the rotational direction. A contact roller 8, a gripper 7, a charger 1 for separating the transfer material
4. A transfer drum 9 which is rotatable in the direction of the arrow in FIG. 1 and has a separation claw 15 and a transfer charger 101 and a transfer material separation charger 13 on the inner circumferential side; Conveyor belt means 16 provided in close proximity to the claws 15
and an apparatus main body 100 disposed close to the terminal end side of the conveyor belt means 16 in the transport direction and extending outside the apparatus main body 100.
It consists of a discharge tray 10 that is detachable from the tray and a fixing layer 17 that is adjacent thereto.

The latent image forming section (2) includes an image carrier, that is, a photosensitive drum 3, which is disposed so that its outer circumferential surface is in contact with the outer circumferential surface of the transfer drum 9, and is rotatable in the direction of the arrow in FIG. 2; A static eliminating charger 1 is disposed near the outer peripheral surface of the drum 3 in the direction of rotation of the photoreceptor drum 3 from the upstream side to the downstream side.
1. A cleaning means 12, a charger 4, and an image exposure means such as a laser beam scanner and an image exposure reflection means such as a polygon mirror for forming an electrostatic latent image on the outer peripheral surface of the photosensitive drum 3. are doing. The rotary developing device ■ has a rotatable housing (hereinafter referred to as "rotating body").
1, and the photosensitive drum 3 mounted in the rotating body 1, respectively.
A yellow developer IY, a magenta developer 1M, and a cyan developer are configured to visualize (that is, develop) an electrostatic latent image formed on the outer peripheral surface of the photoreceptor drum 3 at a position facing the outer peripheral surface of the photoreceptor drum 3. It has a developer tC and a black developer IBK. The developer replenishing device @2 includes a yellow hopper 2Y, a magenta hopper 2M, and a yellow hopper 2Y, a magenta hopper 2M, which are arranged adjacent to the phase V and hold developer for each color supplied from the outside.
It is equipped with a cyan hopper 2C and a black hopper T52BK.

First, the entire sequence of the image forming apparatus having the above-described configuration will be briefly described using a full color mode as an example. When the photoreceptor drum 3 described above rotates in the direction of the arrow in FIG. 2, the photoreceptor on the photoreceptor drum 3 is uniformly charged by the primary charger 4. - When the photoreceptor is uniformly charged by the charger 4, image exposure is performed by the laser beam E modulated by the yellow image signal of the original (not shown), and the electrostatic charge is generated on the photoreceptor drum 3. A latent image is formed, and the electrostatic latent image is developed by the yellow developing device IY, which has been placed in advance at a developing position by the rotation of the rotating body 1.

On the other hand, paper feed guide 5a, paper feed roller 6, paper feed guide 5b
The transfer material conveyed via the gripper 7 is held by the gripper 7 at a predetermined timing.

It is electrostatically wound around the transfer drum 9 by the contact roller 8 and the electrode facing the corresponding contact roller 8 . The transfer drum 9 rotates in the direction of the arrow in FIG.
The image is transferred by the transfer charger 10 at the portion where the outer peripheral surface of the image is in contact with the outer circumferential surface of the image data. The transfer drum 9 continues to rotate once and prepares for transferring the primary color (magenta in FIG. 2).

On the other hand, the photosensitive drum 3 is neutralized by the neutralizing charger 11, cleaned by the cleaning means 12, charged again by the primary charger 4, and subjected to image exposure as described above with the next magenta image signal. . The rotary developing device 1 rotates while an electrostatic latent image based on a magenta image signal is formed on the photosensitive drum 3 by the image exposure, and fixes the magenta developing device IM at the predetermined developing position described above. Following the prescribed magenta development, the above-described process is also carried out for cyan and black, respectively, and when the transfer of the four colors is completed, the four-color developed image formed on the transfer material is Each charger 13
．． 14, the transfer material is released from gripping by the gripper 7, and the transfer material is separated from the transfer drum 9 by a separating claw 15 and sent to the fixing device 17 by the conveyor belt 1B, where a series of full-color prints are carried out. The sequence is completed and the required full-color print image is formed.

Furthermore, according to the present invention, the remaining amount of toner in each of the four hoppers 2Y, 2M, and 2C128K shown in FIG. 2, as shown in FIG. A first developer remaining amount detecting means, that is, toner sensor S1y, Sim, Slc, and 5lbk, which detects whether or not the remaining amount of developer has reached a preset first reference amount; second developer remaining amount detection means, that is, toner sensors S2y, S2m, S2c, 52bk, for detecting whether or not the remaining amount of toner has reached a second reference amount that is smaller than the first reference amount set in advance; The operation section of the image forming apparatus main body 100, in which various operation switches are provided, includes the toner sensors 5ly-3lbk and 52y-32bk.
Based on the drive command signal generated by signal processing according to the detection signal outputted from each of the hoppers 2Y,
Notification means, ie, warning lamps 30Y and 30M, which notify the remaining amount of toner in 2M and 2C52BK.

30C1308K is provided.

The above configuration will be described in more detail as follows. That is, in this embodiment, the hoppers 2Y, 2M,
The toner sensors Sly, Sin, Slc, 5 are set to have a substantially concave shape and a substantially concave volume.
lbk is arranged in each of the hoppers so that the volume of the toner accommodating space created in each hopper when each of the toner sensors 5ty to 3lbk detects that there is no toner replenishes toner to each of these hoppers. It is assumed that the position is set so that the capacity is larger than the capacity of the toner cartridge to be used. On the other hand, each of the toner sensors 52y-52
bk in each of the hoppers is set at a position such that the actual amount of toner remaining in each hopper is almost zero when each of the toner sensors 327-32bk detects that there is no toner. shall be In this embodiment, each of the toner sensors 5ty-3lbk and each toner sensor s27N52bk detects that the toner to be detected is caused by some reason (for example, the amount of toner remaining in each hopper due to toner consumption decreases). When it becomes undetectable (for example, when the level decreases to a level lower than the set point), a signal of logic level "H" is output.

Furthermore, in this embodiment, each of the above-mentioned toner sensors Sl
yN5lbk, the logic level of the detection signal output from 52y-32bk, respectively, and the respective warning lamps 30Y, 3.
The relationship between turning on/off the 0M and 30C1308 is set as shown in FIG. 1 above. That is, the first
As is clear from the figure, when the remaining amount of yellow toner stored in the hopper 2Y is so small that it cannot reach the arrangement position of the toner sensor S2v, let alone the arrangement position of the toner sensor Sly, the above-mentioned IB from both toner sensors
The logic level of the input detection signal is H'', and the warning lamp 30Y corresponding to the hopper 2Y reads the logic level H signal output from each toner sensor 317, 327 and performs image formation for signal processing. Based on a drive command signal from a control unit (not shown) of the apparatus, the yellow toner is turned on to notify the operator, etc. that there is no yellow toner.It is stored in the hopper 2M, which is disposed adjacent to the hopper 2Y. Although the remaining amount of magenta toner exceeds the installation position of the toner sensor 52m,
When the toner sensor Sim has not reached the installation position, only the detection signal output from the toner sensor S1m has a logic level "H". When only the logic level of the detection signal output from the toner sensor S1m is "H", as is clear from the figure, a considerable amount of magenta toner still remains in the hopper 2M. Since the volume of the toner storage space created in the hopper 2M is sufficiently larger than the volume of the toner cartridge that replenishes the hopper 2M with magenta toner,
Even if the magenta toner is replenished from the toner cartridge, the magenta toner will not overflow from the hopper 2M. Therefore, in this case as well, the control unit (not shown) outputs a drive command signal and the warning lamp 30M also lights up. on the other hand,
a hopper 2C disposed adjacent to the hopper 2M;
Regarding the remaining amount of cyan toner and black toner respectively stored in the hopper 28K, the toner sensor Slc,
Since the amount sufficiently exceeds the installation position of 5lbk, the toner sensors Slc, 5lbk, S2c, 52b
A detection signal of logic level ~H'' is not output from any of the control units (not shown), and a drive command signal is not output from the control unit (not shown) to the warning lamps 30C, 308K. lamp 30g
, 308 are all kept in the off state.

Therefore, the operator only needs to replenish yellow toner and magenta toner to hopper 2Y and hopper 2M, respectively, in response to the lighting of warning lamps 30Y and 30M. Even if the magenta toner is replenished, the replenished magenta toner will not overflow from the hopper 2M.

Next, each of the above-mentioned toner sensors 5ty-Slbk, S2Y
When N52bk detects the amount of toner remaining in each hopper 2Y to 2BK, the warning lamps 30Y and 30M are activated.
, 30C1308K will be described with reference to the flowchart shown in FIG. 3.

Regarding any of the aforementioned hoppers 2Y to 28, the control unit (not shown) controls each of the warning lamps 30Y to 308 in response to the detection signals output from the toner sensors 5ly-5lbk and 52y-32bk.
Since the process of turning on/off K is the same, the hopper 2Y will be explained. The control unit (
The arithmetic processing means (not shown) first checks whether a detection signal of logic level "H" is output from the toner sensor S2y, and outputs a detection signal of logic level "H" from the toner sensor S2Y. When it is recognized that there is no yellow toner remaining in the hopper 2Y, the image forming sequence continues as it is assuming that a considerable amount of yellow toner still remains in the hopper 2Y, while a detection signal of logic level "H" is output from the toner sensor S2y. When it is recognized that the toner sensor S2Y is being outputted, the process moves to step 303 (step 301).When it is confirmed in step 301 that the detection signal of logic level "H" is outputted from the toner sensor S2Y, the toner sensor Sly It is checked whether a detection signal of logic level #H# is output, and the toner sensor Sly
When it is recognized that a detection signal of logic level "H" is output from the hopper 2Y (step 303), a drive command signal is sent to turn on the warning lamp 30Y, assuming that there is almost no yellow toner left in the hopper 2Y. At the same time, the process moves to step 307 (step 313
), On the other hand, when it is recognized in step 303 that the detection signal of logic level "H" is not output from the toner sensor S1y, the toner sensors S1y, S
2y has occurred, or only the toner around the toner sensor 527 is carried out and a toner cavity is formed around the toner sensor 323F, which is a so-called toner crosslinking state. For example, the warning lamp 30
In order to make Y blink or display an abnormality on a display unit (not shown) provided separately from the warning lamp 30Y, a drive command signal is output to these means, and the process moves to step 307. (Step 305). When the processing operation shown in Step 305 or Step 313 is completed, it is determined whether the logic level of the detection signal output from the toner sensor Sim of the hopper 2M dedicated to magenta toner is 'H'. When it is recognized that a detection signal of logic level "H" is output from the toner sensor Sim (step 30
7) A drive command signal is output to turn on the warning lamp 30M (step 315). In this way, the toner sensor Slc of the hopper 2C dedicated to cyan toner and the toner sensor 5 of the hopper 2BK dedicated to black toner
The logic level of the detection signal output from each lbk is '''
Step 309 to check whether the level is "H".
311), when it is recognized that the logic level of the detection signal is "H", the warning lamp 30C1308K
A drive command signal is outputted to turn on the respective lights (steps 317 and 319).

In this way, when the execution of the program set for hopper 2Y described above is completed, the programs set for hoppers 2M, 2C, and 2BK will be sequentially executed using the same processing procedure as the above program. .

As explained above, according to the image forming apparatus according to one embodiment of the present invention, it is possible to detect whether or not a plurality of hoppers can be replenished with toner at the same time. replenishment work can be concentrated at the same time,
Therefore, it is possible to reduce the downtime of the main body of the image forming tank 1, and it is also possible to significantly reduce the number of times the operator has to perform toner replenishment work for each of the hoppers. Furthermore, even if a malfunction that adversely affects image formation occurs, such as caking of the toner stored in each hopper or malfunction or malfunction of each toner sensor, these malfunctions will not occur. can now be detected before image formation.
The image forming apparatus according to this embodiment can stably produce high-quality, high-quality images.

As described above, according to the present invention, it is possible to efficiently replenish developer to a plurality of developer replenishing means, and when replenishing developer to the developer replenishing means, It is possible to provide an image forming apparatus in which the image forming apparatus, an operator, etc. are not contaminated by the developer.

[Brief explanation of the drawing]

FIG. 1 shows the storage status of each color toner stored in a plurality of hoppers included in an image forming apparatus according to an embodiment of the present invention, and a plurality of toner sensors disposed in each of these hoppers. It is a diagram showing the relationship between the detection signal inputted from the hopper and the lighting/extinguishing status of a plurality of warning lamps provided corresponding to each of the hoppers. 2 is a vertical sectional view showing the overall configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a diagram showing a flowchart for controlling lighting/extinguishing of a warning lamp provided in an image forming apparatus according to an embodiment of the present invention. IY, LM, Ic, IBK: To developer 2Y, 2M, 2C, 28: Hopper 3: Photosensitive drum 30Y, 30M, 30C130BK: Warning lamp sty
, S is, S lc, S lbk: Toner sensor S 21, S 2s, S 2c, S 2bk
Agent Patent Attorney Akira Kurahashi Figure 3

Claims (1)

[Scope of Claims] 1) An image carrier, a plurality of developing means containing a developer for visualizing the electrostatic latent image formed on the image carrier, and each of the developing means an image forming apparatus comprising a plurality of developer replenishing means provided corresponding to each of the developing means for replenishing developer;
Each of the developer replenishing means includes a first remaining amount of developer detecting means for detecting whether the remaining amount of developer in each of the developer replenishing means has reached a preset first reference amount; and second developer remaining amount detection means for detecting whether the amount of developer remaining in each developer replenishment means has reached a second reference amount that is smaller than the preset first reference amount. , notification means for notifying the state of the amount of developer remaining in each of the developer replenishing means based on a drive command signal generated by signal processing according to the detection signal output from each of the developer remaining amount detection means; established,
Any one of the second remaining developer amount detection means provided in each of the developer replenishing means indicates that the remaining amount of developer in the developer replenishing means has reached the second reference amount. The notification means is driven when the detection signal is output, and the developer is supplied from a first developer remaining amount detection means provided in a developer replenishment means different from the developer replenishment means. An image forming apparatus characterized in that the notifying means is driven also when a detection signal indicating that the amount of developer remaining in the replenishing means has reached the first reference 1 is output. 2) The first and second developer remaining amount detecting means are configured so that the developer remaining amount in the developer replenishing means in which each of the developer remaining amount detecting means is provided is determined based on the first and second standards. 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is configured to output a detection signal of logic level "H" when detecting that the amount has not been reached. 3) The first reference amount of the developer remaining in the developer replenishing means, which is to be detected by the first remaining developer amount detection means, is determined by the first reference amount of developer remaining in the developer replenishing means. Level “H”
The volume of the space in which the developer can be accommodated in the developer replenishing means when the detection signal '' is output is set to be larger than the volume of the toner cartridge that replenishes the developer with respect to the developer replenishing means. The second reference amount of the developer remaining in the developer replenishing means is detected by the second remaining developer amount detecting means, and the second reference amount of the developer remaining in the developer supplying means is detected by the second remaining developer amount detecting means. Claim 1 or 2 is characterized in that the amount of developer remaining in the developer replenishing means is set to approximately zero when a detection signal of level "H" is output. 4) A process of detecting the amount of developer remaining in each of the developer replenishing means, performing signal processing, and driving the notification means using a drive command signal generated by the signal processing. When performing the execution, it is first determined whether the logic level of the detection signal output from the second developer remaining amount detection means is "H", and the logic level of the detection signal is "H". In some cases, it is determined whether or not the logic level of the detection signal output from the second developer remaining amount detection means is "H", and as a result of the determination, the logic level of the detection signal is "H". The image forming apparatus according to any one of claims 1 to 3, wherein the image forming apparatus outputs an abnormality display when it recognizes that the error occurs.