JPS60230169A - Image forming device - Google Patents

Abstract

PURPOSE:To easily detect the color of a formed image, and to prevent image formation in the absence of a developing device and improve operativity by identifying the color of a developing device mounted on an image forming device body and displaying the color of the formed image according to the identified color, and turning off the color display unless no developing device is mounted on the main device. CONSTITUTION:When the power source is turned on after the developing device is set in the image forming body. The color display device 157 on a display panel turns on. Then when a color selection key 156 is pressed, the color (red) of the developing device is selected and a color display device 158 corresponding to the selected color turns on. When the selection switch 156 is pressed again, a copy mode of another color (black) is selected. Whether the developing device is fitted or not is detected from whether a developing device connector is connected or not to send a developing device presence/absence signal and developing device identification (including the color of the developing device) to a computer, and the color of a developer is displayed with the output corresponding to said output signals only when the developing device is set.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an image forming apparatus such as a color copying machine capable of making color copies of a plurality of colors.

[Technical Background of the Invention and Problems Therewith] In recent years, for example, copying machines have become more and more colored, and two-color color copying machines that can obtain images in colors other than black have been put into practical use.

However, in conventional color copying machines of this type, multiple cartridges that integrate a developing device and a photoreceptor are prepared and selectively replaced, which has the problem of being extremely troublesome to operate. .

Recently, a color copying machine has been developed which is equipped with a plurality of developing devices each capable of developing different colors, and which is capable of making color copies of various colors by switching between the developing devices. However, with conventional copying machines, there was no means to notify the user of the color of the image being obtained, so it was not possible to know the color of the image that was being obtained, which not only made copying errors more likely to occur, but also caused problems during operation. There were also problems such as being inferior in gender.

[Object of the Invention] The present invention has been made in view of the above-mentioned circumstances, and its purpose is to select from a plurality of developing devices each capable of developing a different color and install it in the main body of an image forming apparatus. death,
In an image forming apparatus that can form an image of a desired color on an image forming medium using the installed developing device, it is possible to easily know the color of the image to be formed, and it is possible to easily determine the color of the formed image without using the developing device. An object of the present invention is to provide an image forming apparatus that can prevent image formation and improve operability.

[Summary of the Invention] In order to achieve the above object, the present invention selects from among a plurality of developing devices each capable of developing different colors, and installs the developed device in the main body of an image forming apparatus. In an image forming apparatus that can be used to form an image of a desired color on an image forming medium, the color of the developing device installed in the main body of the image forming apparatus is identified, and the color of the image to be formed is determined according to the identification result. At the same time, it is also detected whether or not the developing device is attached to the main body of the image forming apparatus, and when the developing device is not attached, the above-mentioned color is not displayed.

[Embodiment/Example of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a two-color copying machine as an example of an image forming apparatus according to the present invention. That is, 1 is a main body of a copying machine, and on the upper surface of this main body 1, a document table □2 is provided which can freely move back and forth in the left-right direction (in the direction of arrow a in the figure). Further, a paper feed cassette 3 is attached to the right side of the main body 1, and a paper discharge tray 4 is attached to the left side. and,
The cassette cover 5 of the paper feed cassette 3 serves as a manual feeding table 6 for manually feeding paper P2 as appropriate. Further, a photosensitive drum 7 is disposed approximately in the center of the main body 1. Around this photoreceptor drum 7,
A charger 8 for charging, an optical system 9, a two-color developing device 1.0 (described later), a charger 11 for transfer, a charger 12 for stripping, a cleaning device 13, a static elimination lamp 14, and the like are arranged in this order. Further, in the lower part of the main body 1, a sheet P1 automatically taken out from the sheet feed cassette 3 via the sheet feed roller 15 or a sheet P2 manually fed from the manual feed table 6 is placed between the photoreceptor drum 7 and the charged sheet for transfer. Image forming section 1 between the container 11
A paper conveyance path 17 is formed which leads to the paper discharge tray 4 via the paper discharge tray 4 . A registration roller 18 is disposed on the upstream side of the image transfer section 16 of the paper conveyance path 17, and a heat roller 19 and a paper discharge roller 20 as a fixing device are disposed on the downstream side.

Here, the optical system 9 has an exposure lamp 22 whose back portion is surrounded by a reflector 21, mirrors 23 to 26, and a lens 27.

The photosensitive drum 7 is driven by a drive mechanism (not shown) in the direction indicated by the arrow in the drawing in synchronization with the document table 2. First, the exposure lamp 2 is uniformly charged by the charging device 8.
The image of the document uniformly irradiated with light by the optical system 9 is formed on the photoreceptor drum 7 to form an electrostatic latent image. The formed electrostatic latent image is developed into a developer image by the developing device 10 and sent to the transfer charger 11 side. On the other hand, the automatically or manually fed paper P1 or P2 is fed by a registration roller 18, and a developer image previously formed on the photosensitive drum 7 is transferred by a transfer charger 11.

The paper PI (P2) to which this developer image has been transferred is peeled off from the photoreceptor drum 7 by a peeling charger 12, passes through a paper conveyance path 17, and is guided to a heat roller 19, where the transferred image is melted. After being fixed, the paper is discharged to the paper discharge tray 4 by the paper discharge roller 20.

On the other hand, after the developer image is transferred onto the paper PI (P2), the residual toner remaining on the photosensitive drum 7 is removed by the cleaning device 13. l! The remaining image on the photosensitive drum 7 is erased by the static eliminating lamp 14, and the photosensitive drum 7 is prepared for the next copying operation.

In the main body 1, an upper frame and a lower frame (not shown) are pivotally supported at one end via a support shaft (not shown), and the other ends of both frames are rotated at a desired angle, for example, about 30 degrees. It is configured so that it can be opened to Each device such as a charging device 8, an optical system 9, an exposure lamp 22, a developing device 10, a cleaning device 13, and a static elimination lamp 14 are attached to the upper frame around the photosensitive drum 7 by appropriate means. Furthermore, the document table 2 and paper feed roller 15 are also attached to the upper frame, and the upper unit 1
It constitutes A. Further, each mechanism such as a paper feed cassette 3, a transfer charger 11, a peeling charger 12, a heat roller 19, a paper discharge roller 201, a paper discharge tray 4, a main motor 28, etc. are mounted on the lower frame by appropriate means. It is attached to constitute a lower unit 1B. and,
After the front cover of the main body 1 is rotated and removed, it is configured so that it can be opened and closed almost along the paper transport path 17 of the paper PI (P2) via a housing opening/closing device (not shown).

Also, what about 29? lII! This is a blade solenoid that brings the cleaning blade 30 of the device 13 into and out of contact with the photoreceptor drum 7.

Next, details of the developing device 10 will be explained. Second
As detailed in the figure, the first developing roller 311 and the second developing roller 311
These developing rollers 311, 3
12 selectively drives black or one other color,
For example, color development such as red, yellow, blue, and green can be performed.

That is, the developing device 110 is divided into two parts: a first developing device 321 including a first developing roller 31 and a second developing device 322 including a second developing roller 312;
Both the second developing devices 32s and 322 are detachable from the main body 1. In this case, the first developing device 321 in the upper stage
is configured to be easily attached and detached so that the user can pull it out upward in the figure, and the second developing unit 322 in the lower stage is easily visible relative to the main body 1 when a service person performs maintenance or inspection. It is structured so that it can be removed. The frequently used black developer is used in the second developing device 322 in the lower stage, and the color developer is used in the first developing device 321 in the upper stage.

The first developing device 321 includes a developing mechanism section 331 and a developer replenishing section 341. The developing mechanism section 33
1 is provided at the sliding contact portion between the developing roller 311 and the photosensitive drum 7 of the developer magnetic brush 351 formed on the surface of the developing roller 311, that is, upstream of the developing position 365, and A doctor 371 that regulates the thickness of the brush 351 and a developer magnetic brush 35 provided on the surface of the developing roller 311 on the downstream side of the developing position 1361.
1 and guides it to the developer storage section 381.
91 and a developer agitating body 401 accommodated in the developer accommodating portion 381 are housed in a casing 411. A developer concentration detector 421 is attached to the casing 411 at a position above the developing roller 311, which detects the developer concentration by magnetically detecting changes in the magnetic permeability of the developer G1. ing.

Also, the developing roller 31! is a magnetic roll 431 whose center is located on a straight line L2 drawn through the rotation center of the photoreceptor drum 7 and at an angle α (approximately 51°) with respect to the horizontal line L1; The sleeve 441 is fitted onto the sleeve 431 and rotates clockwise in the figure. The magnetic roll 431 has five magnetic pole parts 451 to 491, of which magnetic pole parts 451.47
s and 49s are north poles, and magnetic pole parts 46t and 48t are south poles, the angle θ1 between the magnetic pole parts 451 and 461 is about 50°, and the angle θ2 between the magnetic pole parts 461 and 471 is about 71°. °, the angle θ3 between the magnetic pole parts 471 and 481 is approximately 6
0°, and the angle θ4 of the layer between the magnetic pole parts 481 and 491 is approximately 60°.
' respectively.

Further, the developer replenishment section 341 includes a developer replenishment port 501.
A hopper 511 facing the developer storage section 381 of the developing mechanism section 331, and a developer replenishment roller 5 disposed within the hopper 511 and closing the developer replenishment port 501.
21, and the developer G on the developer supply roller 521 side.
The configuration includes a pair of stirring rollers 531 and 531 that stir the developer G1 in the hopper 511 so as to convey the developer G1.

Further, the second developing device 322 is similar to the first developing device 322 described above.
It has almost the same basic configuration as 1, and the developer supply section 34
2, the shape of the hopper 512, the arrangement structure of the magnetic poles of the magnetic roll 432 of the developing roller 312, the mounting position of the developer concentration detector 422, and the accompanying narrow width (approximately 50 #I1
The difference is that a scraper 54 having an inclination of approximately 20 degrees is added. Therefore, other identical components will be designated by symbols with the suffix character changed from "!" to "2", and detailed explanations will be omitted. Note that the magnetic roll 432 of the developing roller 312 has four magnetic pole parts 452 to 4.
82, of which the magnetic pole parts 452 and 472 are N poles,
The magnetic pole parts 462 and 482 are S poles, and the magnetic pole parts 45
The angle θ5 between 2 and 462 is about 78°, and the magnetic pole part 462
The angle θ6 between the magnetic pole portions 472 and 472 is approximately 70°, and the angle θ7 between the magnetic pole portions 472 and 482 is approximately 80°. Further, the magnetic roll 432 is provided such that its center is located on a straight line L:I that passes through the rotation center of the photosensitive drum 7 and forms an angle β (approximately 1°) with respect to the horizontal line L1. .

On the other hand, each of the magnetic rolls 431 and 432 of the first developing device 321 and the second developing device 322 is configured to be able to rotate at a rotation angle of approximately 25 degrees. Along with the displacement operation, the developing row 5311.3
Developer magnetic brushes 3, 51, 352 can be formed on the surface of 12 or removed. Then, the magnetic rolls 431 and 432 of the first developing device 321 and the second developing device 322 are connected to magnetic roll driving means, which will be described later.
By switching to a predetermined position, the first developing unit 3
2! Alternatively, the developer magnetic brush 35 is applied only to the surface of one of the developing rollers 311 and 312 of the second developing device 322.
s, 352 are to be formed.

That is, when operating the first developing device 321 side,
As shown in FIG. 2, the magnetic roll 4 on the first developing device 321 side
31 with the magnetic pole part 471 facing the development position 361, and a doctor 37 placed approximately halfway between the magnetic pole parts 451 and 461.
1 is positioned, and the magnetic roll 432 on the second developing device 322 side is set so that the magnetic pole portion 452 faces the doctor 372. The developer magnetic brush 351 is formed only on the surface of the developing roller 311 on the first developing device 321 side.

In addition, when operating the second developing device 322 side, the third developing device 322 side is operated.
As shown in the figure, a magnetic roll 431 on the side of the first developing device 321
Rotate about 25 degrees clockwise from the position shown in FIG. 2 to make the magnetic pole part 451 face the doctor 375, and move the magnetic roll 432 on the second developing unit 322 counterclockwise from the position shown in FIG. The doctor 372 is rotated approximately 25 degrees in the direction so that the doctor 372 is located approximately midway between the magnetic pole portions 452 and 462. The developer magnetic brush 352 is formed only on the surface of the developing roller 312 on the second developing device 322 side.

In addition, the magnetic pole parts 45 and 45 of the magnetic rolls 431 and 432
The reason why the developer magnetic brushes 3, 51, 352 are not formed on the surfaces of the developing rollers 311, 312 when the magnetic brushes 3, 51, and 352 are not formed on the surfaces of the developing rollers 311, 312 is that when the magnetic brushes 3, 51, and 352 are opposed to the doctor blades 371 and 372 made of non-magnetic material, the magnetic pole portions 45x and 452 are This is because the power to adsorb the developers Gs and G2 is weak because the density is in a slender state, and therefore it can be easily regulated by the doctor blades 371 and 372, and even when the sleeves 441 and 442 rotate, the developer Gt will not be absorbed.

G2 never passes through the doctor part 371 and 372.

By the way, each drive unit of the first developing device 321, that is, the sleeve 441 of the developing roller 311, the developer stirring body 405,
A driving force is transmitted to the developer replenishing roller 521 via a first driving force transmission system 61, which will be described later. Further, driving force is transmitted to each drive unit of the second developing device 322, that is, the sleeve 442 of the developing roller 312, and the developer stirring body 402 via a second driving force transmission system 62, which will be described later. . The first and second drive transmission systems 61.
Reference numeral 62 has a configuration as shown in FIGS. 4 to 6, and a rotatable motor 63 serving as a common driving source rotates forward or reverse to operate the first and second developing units 32s.
, 322, only one of the drive systems is selectively operated.

Hereinafter, the driving force transmission system will be explained in detail with reference to FIGS. 4 to 6. The first driving force transmission system 61 includes an intermediate gear 65 that meshes with a drive gear 64, a first driven gear 66 that meshes with this intermediate gear 65, an intermediate gear 67 that meshes with this driven gear 66, and an intermediate gear 67 that meshes with this driven gear 66. 2nd meshing with 67
It has a driven gear 68. Further, the second driving force transmission system 62 includes a third driven gear 69 that meshes with the driving gear 64.
, an intermediate gear 70 that meshes with this driven gear 69 , and a fourth driven gear 71 that meshes with this intermediate gear 70 . Then, when the driving gear 64 rotates normally, that is, in the six directions shown by the solid line arrows in FIG.
When the gears 9 to 71 rotate in the direction of the solid line arrows, and the drive teeth 1!64 rotate in the reverse direction, that is, in the direction of the broken line arrow B in FIG. Each of the gears 69 to 71 of the driving force transmission system 62 rotates in the direction of the dashed arrow.

Further, the first driven gear 66 is connected to the drive shaft 721 that is integrated with the sleeve 441 of the first phenomenon roller 311, and the second driven gear 68
are attached to the drive shaft 731 of the developer stirring body 401 via one-way clutches 74 and 74, respectively, and the drive shafts 721 and 731 have gears 66 and 68 that rotate in the direction of the solid line arrow, that is, drive gears. The driving force is transmitted only when 64 rotates in the normal direction, and the rotation occurs in the direction of the dashed line arrow. Further, the third driven gear 69 is connected to the drive shaft 722 that is integrated with the sleeve 442 of the second developing roller 312, and the fourth driven gear 71 is connected to the drive shaft 722 of the developer agitator 402.
2 through one-way clutches 75, 75, and each of the drive shafts 72' 2, 732 is connected to a gear 6.
9.71 respectively rotate in the direction of the dashed arrow, that is, the driving force is transmitted only when the drive gear 64 is reversed, and one point m
It is designed to rotate in the direction of the ll arrow.

Further, the driving gear 64 has a bearing 7 as shown in FIG.
The drive shaft 78 of the reversible motor 63 is rotatably supported via the gear mechanism 77.
It is attached to a rotating shaft 79 that interlocks with the. That is,
A gear 80 is attached to the rotating shaft 79, and this gear 80 is mounted on a support shaft 83, which is installed between a motor mounting frame 81 and a stay 82 integrated therewith, through bearings 84 and 84.

It meshes with a gear 85 which is rotatably attached. A gear 86 having a larger diameter than the gear 85 is integrally formed with the gear 85, and the gear 86 meshes with a gear 87 attached to the drive shaft 78 of the motor 63.

Thus, the rotation of the drive shaft 78 of the reversible motor 63 in both forward and reverse directions is transmitted to the rotation shaft 79 via the gears 87, 86, 85, 80, and thereby the first and second developing devices 321
322 can be selectively operated simply by switching the reversible motor 63 between forward and reverse rotation.

Note that switching between forward and reverse rotation of the reversible motor 63 is performed by pressing a color selection key on the operation panel, which will be described later, and at this time, the non-operating magnetic roll 43 * , 432 so that the magnetic pole portions 45s, 452 of the doctors 37s, 372 are switched to face the doctors 37s, 372.

Further, an intermediate gear 65 that meshes with the driving gear 64 and the first driven gear 66 is rotatably attached to a support shaft 89 via a bearing 88.

The support shaft 89 is a bearing 76°76 that pivotally supports the rotating shaft 79.
The drive gear 64 and the first driven gear 64 are attached to an arm 91 that can swing around a housing 90 that holds the drive gear 64 and the first driven gear 64. [It is designed so that its position can be changed so that it can reliably mesh with 1l166.

Further, one stirring roller 531 of the first developing device 321 is
It is intermittently driven via a first operating mechanism 921 shown in FIG. 4, and the other stirring roller 5531 and developer supply roller 521 are simultaneously driven in conjunction with the movement of the stirring roller 531. It looks like this.

That is, one stirring roller 531 of the first developing device 321
A ratchet gear 941 is attached to one end of the shaft 931, and this ratchet gear 941 is attached to a solenoid 95.
It is intermittently driven by a predetermined amount via a ratchet pawl 971 attached to a swinging arm 961 that rotates and displaces in conjunction with the on and off operations of 1. Further, sprockets (not shown) are fitted to the shafts 931.98 of the stirring rollers 531, 531 and the shaft 991 of the developer replenishing roller 521, respectively, and an endless chain (not shown) is strung around them. The stirring roller 53 is connected via this driving force transmission system (not shown).

531 and the developer supply roller 52 are driven together.

Further, the stirring roller 532 and the developer replenishing roller 522 of the second developing device 322 are simultaneously driven intermittently through a second operating mechanism 922 having the same configuration as the first operating mechanism 921 and a driving force transmission system having approximately the same configuration. It is now possible to do so. Note that the same constituent parts as the first actuation mechanism 921 are given the reference numerals with the suffix character changed from "ENG" to "2", and detailed explanation thereof will be omitted.

Next, the structure of the magnetic roll driving means 1001 (1002) for rotationally displacing the magnetic roll 431 (432) in order to form or remove the developer magnetic brush 351 (352) on the surface of the developing roller 311 (312). will be explained with reference to FIGS. 7 to 9(a) and (b). The shaft 1011 (101) of the magnetic roll 431 (432)
2) One end is attached to the bearing 1 attached to the frame 102.
03, and a lever 10 is attached to the tip of the shaft.
4 is installed. The tip of this lever 104 is connected to an arm 106 rotatably attached via a support shaft 105.
It is in a state where it is engaged with the engagement groove 107 of. moreover,
Support part 1 formed at the lower part of the pivot end side of the arm 106
08 is connected to the plunger 110 of the solenoid 109, and one end of a tension spring 112 is connected to a support portion 111 formed at the upper portion of the pivot end side.

Therefore, when the solenoid 109 is off, the arm 106 is moved to the eighth position by the urging force of the tension spring 112.
The magnetic pole portion 45s (452) is moved to the position indicated by the two-dot chain line in the figure, that is, as shown in FIG. 9(a), with the doctor 371 (3
The lever 104 is held in a position facing the lever 72). Therefore, when the solenoid 109 is off, the developer magnetic brush 35N <352 ) is not formed on the surface of the developing roller 311 (312). Further, when the solenoid 109 is in the ON state, the arm 106 is moved to the position shown by the solid line in FIG. 8 due to the biasing force of the tension spring 112, that is, the position shown in FIG.
As shown in , the magnetic pole part 451 (452) is
The lever 104 is rotated to a position facing (372). Therefore, solenoid 1
09, a developer magnetic brush 351 (352) is formed on the surface of the developing row 5311 (312).

By the way, as shown in FIGS. 2 and 3, the doctor 372 described above includes a doctor body 1132 made of a non-magnetic material, and a magnetic body 114 made of a band-shaped iron plate provided along the longitudinal direction of this doctor body 1132. , doctor body 113
A magnetic body 1152 consisting of an iron plate provided at both ends of the magnetic body 1152.
1152 (only one is shown). The magnetic material 114, 1152, 1152 has a magnetic pole portion 452 facing the doctor 372 and the developing roller 3.
When removing the developer G2 on the surface of the magnetic pole part 4
The configuration is such that lines of magnetic force are formed between the developer G2 and the developer G2 to more reliably prevent the developer G2 from being taken out. Also, Doctor 3
71 has a structure including a doctor body 1131 made of a non-magnetic material and magnetic bodies 1151 and 1151 (only one shown) made of iron plates provided at both ends of this doctor body 1131, and is similar to the doctor body 1131 described above. Similarly to the case of No. 372, removal of the developer Gl is prevented. This doctor 371 is not provided with a magnetic body along the longitudinal direction of the doctor main body 1131 like the doctor 372 described above, and the magnetic pole portion 451 of the developing roller 311 and the 11-pole portion of the developing roller 312 facing the doctor 371 are not provided. 482 to prevent the developer G1 from being taken out.

Further, a magnetic plate 116 is provided between the developing roller 311 and the developing roller 312, as shown in FIGS. 2 and 3, and the magnetic flux density and polarity of the other magnetic roller 431 (432) The influence of distribution is weakened, and a good developer conveyance operation can be performed.

Note that 1172 shown in FIGS. 2 and 3 is a developer remaining amount detection device that detects when the amount of developer G2 in the hopper 512 of the second developing device 322 has fallen below a predetermined value. A configuration in which a permanent magnet 120 attached to an actuator 119 integrated with a detection lever 118 that rotates according to the amount of rotation is activated when it approaches a reed switch 121 as a detector provided outside the hopper 512. It has become. Further, although not shown, a developer remaining amount detecting device 1171 having a configuration similar to the developer remaining amount detecting device 1172 is provided for the hopper 511 of the first developing device 321 as well.

Further, as shown in FIGS. 2, 3, and 10, a hopper cover 131 that forms part of the upper surface of the main body 1 is provided on the upper surface side of the developing device 10 so as to be openable and closable. Lid body 1331 opens and closes the top opening 1321 for replenishing developer of the first developing device 321 and the top opening 132 of the second developing device 322 for replenishing developer.
A lid body 1332 that opens and closes 2 is exposed.

By opening the lids 1331 and 1332, the developer G1. G2 can be easily replenished from the top side. In addition, the lid bodies 133r, 133
2 has a color display section 134t.

1342 is provided, and the developer G housed inside.
1. The color of G2 can be easily distinguished, and developer of a different color is not mixed in by mistake.

Further, 135 shown in FIGS. 2 and 3 is a cover opening/closing detection device for detecting opening/closing of the hopper cover 131, and a permanent magnet 13 attached to the tip of the hopper cover 131
6, and a reed switch 137 as a detector which is provided on the main body 1 side and turns on when the magnet 136 approaches when the hopper cover 131 is closed.

Further, as shown in FIGS. 10 and 11(a) and (b), the hoppers 511 of the first and second developing devices 32r and 322
, 512 and the lid body 1331.
．． On both sides of 1332, cumulative time meters 1391 and 139 are used as life indicators to display the developer life.
2, and a developer-free indicator 140 that indicates that the amount of developer in the hoppers 511 and 512 has fallen below a predetermined amount!
, 1402 are provided. The above cumulative time meter 1391
1392 indicates the life of the developer by measuring the amount of rotation (time) of the sleeves 441 and 442 that constitute the developing rows 5311 and 312, for example. I am using an electrolytic type integrating time meter (trade name: FC timer).

On the other hand, the first developing device 32 containing the color developer Gl is a cartridge type that can be attached to and detached from the main body 1, and can be pulled up with the handle 141 (see FIG. 10) in an upright position. It can be easily removed and removed. That is, the developer supply section 34 of the first developing device 321
Positioning members 142 and 142 (only one is shown) are attached to both the front and rear walls of 1, and these positioning members 1
42. The handle 141 is attached to 142 via the support shafts 143, 143.
Both end support portions 144, 144 are rotatably pivoted. The support portions 144 and 144 of the handle 141 have hooks 145 that are rotatable about the support shaft 143, as shown in FIGS. 12 and 13(a), (b), and (c), respectively.
is integrally attached, and is configured to engage with a locking pin 146 provided on the main body 1 side to prevent upward movement. Furthermore, the engagement groove 147 as a first positioning part and the end face 148 as a second positioning part formed on the lower end side of the positioning member 142 engage with the positioning pins 149 and 150 provided on the main body 1 side. The first developing device 321 can be held in a predetermined position by making contact with the first developing device 321. Then, when the handle 141 is erected, the seven grips 14 are opened as shown in FIG. 13(a).
When the engagement between the hook 145 and the locking pin 146 is released and the handle 141 is brought down to a substantially horizontal position, the hook 145 becomes engaged with the locking pin 146 as shown in FIG. By pushing it further, the hook 145 and the locking bottle 146 are surely engaged to press the first developing device 321 downward, as shown in FIG. 13(C). Therefore, if the handle 141 is in an upright state, the device 321 can be attached and detached in the first state, and the first developing device 321 can be attached and detached.
By folding down the handle 141 after inserting the first developing device 321, the first developing device 321 can be fixed, making the operation extremely easy.

Next, the developing operation of the developing device 10 will be explained. First, when the first developer 321 side is selected to operate using the color selection key, the magnetic rolls 43s and 432 are moved to #I2.
When the state shown in the figure is reached, the reversible motor 63 rotates forward, and the sleeve 441 of the first developing roller 311 rotates clockwise in the state shown in FIG. 2, forming a developer magnetic brush 351 on the surface of the sleeve 441. . Then, the static latent image formed in advance on the photoreceptor drum 7 is developed with the color developer G1. In this way, as soon as the development of the electrostatic latent image is completed, the magnetic roll 431 is rotated by about 25 degrees so that the magnetic pole part 451 faces the doctor 371, and thus the developer magnetic brush 351 is transferred onto the sleeve 441. The cutting process is stopped, and in this state, the sleeve 441 further rotates by a predetermined amount until it reaches 1! Edging magnetic brush 3
51 is removed. Note that at this time, the second developing roller 31
2 also does not have a developer magnetic brush 352 formed thereon.

Next, even if one of the developing devices 321 and 322 is selected, problems such as color mixing will not occur.

Further, when the second developing device 322 is selected for black color development, the magnetic rolls 43s and 432 enter the state shown in FIG. rotates clockwise in the state shown in FIG. - forming an agent magnetic brush 352; After developing the electrostatic latent image on the photoreceptor drum 7 to black in the same manner as described above,
The developing operation ends with the developer magnetic brush 352 removed from the surface of the sleeve 442.

Note that the developer stirring body 401 (402) and the stirring roller 53 of the developing device 321 (322) in the developing operation state
1 (532) is always operating, and the developer replenishment roller 52r (522) is the developer concentration detector 421.
The developer Gl (02) is appropriately replenished by a control signal based on the output signal of (422), thereby maintaining a good developing operation.

FIG. 14 shows the operation panel, including a copy key 151 for executing a copy operation, an interrupt key 152 for specifying an interrupt mode for interrupt copying, and an interrupt key 152 for specifying an interrupt mode for interrupt copying. 153, a numeric keypad 154 for setting the number of copies, a number display section 155 for displaying the number of copies, a color selection key 1561 for selecting the copy color (for example, black, red, blue, green), and a selected color. Color display units 157 to 160 to display, ff to display operating status, etc. Display section 161; degree setting section 162 for setting copy density;
etc. are provided for each. The liquid crystal display section 161
, 163 is a symbol for indicating that copying is possible, 164 is a symbol for indicating that copying is not possible, and 165 is a symbol for indicating that copying is not possible.
is currently 11188! This is a symbol for indicating that there is no developer left in the hopper of f10. Note that the color selection by the color selection key 156 can be alternately selected each time the color selection key 156 is pressed. That is, for example, the first Tja imager 32! If the color is red and the second developing device 322 is black, then tal
! At the time of input, the automatic copying mode is set to black copying mode, the second developing device 322 is selected, and the color display 157 lights up. When the color selection key 156 is pressed in this state, the red copy mode is entered, the first developing device 321 is selected, and the color display 158
lights up. If the color selection key 156 is pressed again in this state, the black copy mode is set again. In this way, each time the color selection key 156 is pressed, the black copy mode and the red copy mode can be selected alternately.

FIG. 15 shows the overall control circuit.

That is, 171 is a microcomputer (hereinafter simply referred to as microcomputer) as a main control unit, and controls the tqm of the entire copying machine. Inputs to the microcomputer 171 include input switches 173 such as various keys on the operation panel, various other switches necessary for the copying operation, sensors 174, and the developing device 321 through the input interface circuit 172. The developer 11 degree detector 421, the developer amount detector 117t, and the developer 1 of the second developer 11322
Once detector 422 and developer remaining fII detector 117
2. The cover open detection device 135 and the like are connected.

Further, a storage device 175 is connected to the microcomputer 171, and this storage device 175 is backed up by a backup power source 1176 such as a battery. On the other hand, an output interface circuit 177 is connected to the output of the microcomputer 171.
The display W1178 such as various indicators and display parts of the operation panel, each pole position switching solenoid 109, 10 of the first developer 321 and second developer 322
9. The reversible motor 63 and the first developing device 321
Total time meter 1391. An integrated time meter 1392 of the second developer 322, a developing bias power source 179, a charging power source 180 of the charging charger @8, a transfer power source 181 of the transfer charger 11, and a stripping charger 1112 of the stripping charger 11. 11
1[182, the static elimination lamp 14, the developing device absent indicator 140r, 1402, the main motor 28, other various solenoids l1i183, the original platen driving device 184 that drives the original platen 2, the exposure lamp IIJl! N185 etc. are connected once. Above exposure lamp control circuit 1
Reference numeral 85 controls the exposure lamp 22 in accordance with an output signal from the automatic exposure sensor 186 that detects light from the exposure lamp 22 and a signal from the microcomputer 171.

Note that the first developing device 321 and the second developing device 322 each have a developing device presence/absence signal generating means 18 that indicates the presence or absence of the developing device.
71.1872 and identification information generating means 188s and 1882 for generating an identification code unique to the developer (which also represents the color of the stored developer), and signals and identification codes from these are also input to the input interface circuit 172. is inputted to the microcomputer 171 via. The developer presence/absence signal generation means 187r, 1872 and the identification information generation means 188r, 1882 utilize a developer connector for electrically connecting the developer to the control circuit, as shown in FIG. 16, for example. Each of them is designed to generate a signal and an identification code. That is, 191 is the above-mentioned connector, which is composed of a jack 192 and a plug 193. The jack 192 is provided on the developing device side, and the plug 193 is connected to the control circuit shown in FIG. 15 via a cable. In the jack 192, a terminal 1941 is set as a common terminal, and a developing device presence/absence signal is generated by connecting this terminal 1941 and a terminal 194s, and also connecting the terminal 1941 and terminals 1942 to 1944 according to the developing device. By doing this, a 3-bit identification code is generated. on the other hand.

In the plug 193, a terminal 195 is grounded on the control circuit side, and terminals 1952 to 195i are connected to the input interface circuit 172. Therefore, when the jack 192 and the plug 193 are connected, the respective terminals are connected correspondingly, and thus three pits are identified according to the connection state of the terminals from the terminals 1952 to 1954 of the plug 193 to the terminals of the weft jack 192. A code is obtained, and a developing device presence signal is obtained from the terminal 195s. Therefore, jack 192 and plug 193
If not connected, terminal 195 of plug 193
Since the developing device presence signal cannot be obtained from s, it can be determined that there is no developing device (the developing device is not installed).

Further, the storage device 175 is, for example, 0MO8RAM.
(Random Access Memory), which is used as a counter to count the number of copies (number of copying operations).
The details will be explained below.

That is, in this embodiment, for example, a plurality of sheet number counters for each developing type are provided to count the number of sheets for each developing device, and one total sheet number counter is provided for counting the total number of sheets. They are selected by addressing according to the device's identification code, and count data is stored in each one. The count data of each sheet number counter is composed of, for example, 4 bits x 5, and is stored in a BCD code. Further, the count data of the total number counter is composed of, for example, 4 bits x 6, and is stored in a BCD code.

Next, the operation in the above configuration will be explained. First, the operation when the power is turned on will be explained using the flowchart shown in FIG. When the power is turned on, the process proceeds to step A1. In step A1, the second developing device 322 containing black developer as a reference color is selected, and the automatic exposure mode is selected, and the process proceeds to step A2. In step A2, the heater lamp of the heat roller 19 is turned on, and the process proceeds to step A3. In step A3, the pole position switching solenoid 109 of the second developing device 322 is turned off and the reversible motor 63 is reversed, and the process proceeds to step A4. In step A4, the reversible motor 63 is stopped, and the process proceeds to step A5.

In step A5, the pole position switching solenoid 109 of the first developing device 321 is turned off, and the reversible motor 63 is turned off.
Turn forward and proceed to step 86. In step 80, the reversible motor 63 is stopped, and the process proceeds to step A7. In step A7, the main motor 28 is turned on for a certain period of time,
Proceed to step A8. In step 88, it is checked whether or not the warming up of the heat roller 19 has been completed, and if it has been completed, the symbol 163 for displaying copy permission on the operation panel is lit to enter the standby state, and step A9
accepts key operations on the operation panel.

Next, the process proceeds to step A10, and it is checked whether or not the interrupt key 152 is turned on. If it is not turned on, the process proceeds to step A11, and if it is turned on, the process proceeds to step AI2. In step A12, it is checked whether or not the current mode is interrupt mode, and if the mode is not interrupt mode, the process advances to step A13. In step A13, the copy conditions immediately before the interrupt key 152 is turned on, that is, copy density, copy color, and set number of copies, are saved, and the second developer 322 containing black developer and the automatic exposure mode are saved. Then, set the set number of copies to "1", set the interrupt mode, and proceed to step A14. In this manner, when the interrupt mode is set, the immediately preceding copying conditions are saved and the copying mode is switched to black as the reference color. Next, in step A14, the interrupt indicator 153 on the operation panel is turned on, and the process proceeds to step A11. on the other hand,
If the interrupt mode is selected in step A12, the process proceeds to step A15. In step A15, step A
The copying conditions saved in step A13 are restored, and the selection of the developing device and exposure mode is returned to the selection state immediately before the start of the interrupt mode, the interrupt mode is canceled, and the process proceeds to step A16. In step A16, the interrupt indicator 153 on the operation panel is turned off, and the process proceeds to step A11.

In step A11, it is checked whether or not the second developing device 322 is installed based on the developing device presence/absence signal from the second developing device 322, and if it is not installed, the process advances to step A17. In step A17, it is checked whether or not the first developing device 32 is installed based on the developing device presence/absence signal from the first developing device 321. If it is not installed, step A17 is performed.
Proceed to step 18. In step A18, the color indicators 157 to 160 and the copy permission display symbol 163 on the operation panel are displayed.
turn off and return to standby mode.

In this way, the first developing device 321 and the second developing device 32
2 is not installed at all, color indicators 157 to 16
This prohibits the display of colors based on 0. On the other hand, in step A11, if the second developing device 322 is installed, the process advances to step A19. In step A19, it is checked whether the first developing device 321 is installed, and if it is installed, the process advances to step A20. In step A20, it is checked whether the color selection key 156 is turned on, and if it is turned on, the process advances to step A21. In step A21, it is checked whether the second developing device 322 is currently selected, and if it is not selected, the process advances to step A22. In step A22, the second developing device 32
Select 2 and proceed to step A23. Above step A1
9, if the first developing device 321 is not installed, step A20. Jump A21 and step A2
Proceed to step 2. Further, if the color selection key 156 is not turned on in step A20, step A21.
Jump to A22 and proceed to step A23. On the other hand, if the first developing device 32t is installed in step A17, or if the second developing device 32t is installed in step A21,
If the developing device 322 has been selected, the process advances to step A24. In step A24, the first developing device 321 is selected, and the process proceeds to step A23. In this way, the first developing device 32
If either the second developing device 322 or the second developing device 322 is not installed, selection of that developing device is prohibited. In step A23, the color of the selected developer is displayed.

That is, the color of the stored developer is determined based on the identification code output from the selected developer, and a color indicator on the operation panel corresponding to the determined color is turned on. For example, if the discrimination color is black, the color display 157 is turned on, and if the discrimination color is red, the color display 158 is turned on.

After color display is performed in this way, the process advances to step A25. In step A25, the developer remaining amount detection device 1171.117
2, the first and second developing units 321 and 322
It is checked which of the developing devices is out of developer or not, and if neither is out of developer, the process advances to step A26. In step A26, the first and second developing devices 32r, 3
22 developer-free indicators 140s and 1402 are turned off, and the process proceeds to step A27. On the other hand, the above step A25
If either developing device is out of developer, the process advances to step A28. In step A28, it is checked whether the hopper cover 131 of the developing device M1o is closed or not based on the signal from the cover opening/closing detection device 135. If it is closed, the process proceeds to step A26, and if it is not closed, the process proceeds to step A29.

In step A29, the developer empty indicator 1401 or 1402 of the corresponding developing device (developing device without developer) is turned on, and the process proceeds to step A27. In this way, the first and second
When the developers Gs and G2 run out in the hoppers 51s and 512 of the developing devices 321 and 322, the upper opening 1
This is to light up the developer-free indicators 140r and 1402 provided in the vicinity of 321 and 1322. At this time,
If the hopper cover 131 is closed, the no-developer indicators 1401 and 1402 are not lit, but are lit only when the hopper cover 131 is opened. In step A27, it is checked whether the developing device selected at this time is out of developer, and if not, the process proceeds to step A30. In step A30, the symbol 165 for displaying the absence of developer on the operation panel is turned off, and the process proceeds to step A31. on the other hand,
In step A27, if the selected developing device is out of developer, the process advances to step A32. Step A
32, symbol 1 for displaying no developer on the operation panel
65 is turned on, and the process proceeds to step A31. in this way,
This is displayed on the operation panel only when the selected developing device runs out of developer.

In step A31, it is checked whether there is any abnormality in the copying machine, and if there is an abnormality, the abnormality processing is performed, and if there is no abnormality, the process advances to step A33.

In step A33, it is checked whether the mode is a manual paper feed mode using the manual feed table 6, and if it is not the manual paper feed mode, the process proceeds to step A34.

In step A34, it is checked whether or not there is paper P1 in the paper feed cassette 3. If there is not, the process returns to the standby state, and if there is, the process proceeds to step A35. On the other hand, the above step A
33, if it is manual paper feeding mode, step A3
4 and proceed to step A35. Step A3
In step 5, it is checked whether the developer has been attached or detached based on the developer presence/absence signals from the first and second developer units 321 and 322, and if the developer has been attached or detached, the process advances to step A36. Step A
At step 36, it is checked based on the signal from the cover opening/closing detection device 135 whether or not the developing device is securely attached. In this case, the cover opening/closing detection device 135
If it detects that it is closed, it is determined that it is attached. When it is determined that the developing device is attached, the process advances to step A37. Step A
At step 37, the developer on the sleeve of the detached developing device is removed by performing the above-described operations, and the developing device returns to the standby state. In this way, when a developing device is attached or detached while the power is on, the device operates to remove the developer on the sleeve of the detached developing device after the developing device is securely attached. It is. On the other hand, if the developing device is not attached or detached in step A35, the process advances to step A38. In step A38, it is checked whether or not the copy key 151 on the operation panel is turned on. If it is turned on, the process proceeds to a copying operation to be described later. If it is not turned on, the process proceeds to step A39. In step A39, it is checked whether or not any key operation has been performed on the operation panel for a certain period of time. If any operation has been performed, the process returns to the standby state, and if no operation has been performed, the process advances to step A40. In step A40, it is checked whether or not the current mode is interrupt mode, and if the mode is not interrupt mode, the process proceeds to step A41. In step A41, the second developing device 322 containing the black developer and the automatic exposure mode are selected, the set number of copies is set to "1", and the process returns to the standby state. In this way, if no operation is performed for a certain period of time after the normal copying operation is completed, the mode is switched to the black copying mode as the reference color and the automatic exposure mode. On the other hand, in step A40, if it is the interrupt mode, the process advances to step A42. In step A42,
The copying conditions saved when setting the interrupt mode are restored, the interrupt display 153 on the operation panel is turned off, and the standby state is returned. In this way, if no operation is performed for a certain period of time after interrupt copying is performed in interrupt mode, the state is returned to the state immediately before starting interrupt mode.

Next, the copying operation will be explained using the flowchart shown in FIG. 18.≦When the copying key 151 on the operation panel is turned on, the process proceeds to step B1.

In step B1, the pole position switching solenoid 109 of the selected developing device is turned on, and the process proceeds to step B2. In step B2, the reversible motor 63 is rotated in the direction of the selected developing device, and the process proceeds to step B3. In step B3, the blade solenoid 29 of the cleaning device 13, the static elimination lamp 14, the main motor 28, the transfer power source 181 (transfer charger 11), and the peeling charger! l! 182 (stripping charger 12) and developing bias voltage III 79 are turned on, respectively, and the process proceeds to step B4. In step B4, the paper feeding operation from the paper feeding cassette 3 is started, and the process proceeds to step B5. In step B5, it is checked whether or not the document table 2 is in the normal position. If it is not in the normal position, the process proceeds to step B6 and is returned to the normal position. When the document table 2 is returned to the normal position, the process proceeds to step B7. In step B7, the exposure lamp 22 is turned on, and the process proceeds to step B8. In step B8, the charging power source 18
0 (charger 8) is turned on to start charging the photosensitive drum 7, and at the same time, the document table 2 is moved forward to start scanning the document, and the process proceeds to step 6 B9. In step B9,
Rotate the registration roller 18 to transfer the paper P1 to the image transfer section 1.
6 and proceeds to step 810.

In step 810, the sheet number display section 15 on the operation panel
5 is subtracted by "1", and the storage device 17
The total sheet number counter in 5 and the sheet number counter of the selected developing device are each incremented by 1, and step B11
Proceed to. In step B11, the charging power source 180 is turned off to stop charging the photosensitive drum 7, and the process proceeds to step 812. In step 812, the exposure lamp 22 is turned off,
Proceed to step Bi3. In step 813, the original platen 2
is moved backwards and the process proceeds to step 814. In step B14, it is checked whether the document table 2 has returned to the normal position, and if it has returned to the normal position, the process proceeds to step B15. In step B15, the rotation of the registration roller 18 is stopped, and the backward movement of the document table 2 is also stopped, and the process proceeds to step 816. In step 816, it is checked whether or not the set number of copies have been completed, and if so, the process advances to step 817. In step B17, it is checked based on the signal from the developer concentration detector of the selected developer whether the developer concentration in the selected developer is at least the lower limit concentration level, and if it is at least the lower limit concentration level, step 818 If the concentration level is not higher than the lower limit concentration level, the process advances to step B19. Step B19
Then, it is checked whether or not the developer has been continuously replenished for a certain period of time. If not, the process returns to step 817 and the above operation is repeated, and when the developer has been continuously replenished for a certain period of time, the process proceeds to step 818. In other words, in automatic developer concentration control, there is an appropriate concentration level and a lower limit concentration level for not changing the flow characteristics of the developer. The drive·
Then, the developer continues to be replenished. Step 818
Then, the pole position switching solenoid 109 is turned off and the process proceeds to step B20. In step 820, the reversible motor 63 is stopped, and the process proceeds to step 821. Step B21
In this case, the blade solenoid 29, the main motor 28, the static elimination lamp 14, the transfer power source 181, and the peeling power source 11118.
2 and the developing bias power supply 179 are respectively turned off to return to the standby state.

On the other hand, if the set number of copies have not been completed in step 816, the process advances to step B22. Step B
In step B22, the life of the developer is checked by checking whether the value of the sheet number counter for each development type in the storage device 175 is a predetermined value set in advance, and if the life has not expired, step B23 Proceed to. In step B23, it is checked whether there is a color change request by checking whether a color change request flag, which will be described later, is set to 1'', and if there is no color change request (flag - ○).
Returning to step B4, the above-described operations are repeated, and if there is a color change request (flag-1), the process proceeds to step B24.

In step 824, the selection of the developing device is changed, and the process proceeds to step B25.

In step B25, the pole position switching solenoid of the previously selected developer is turned off, and the process proceeds to step 826. In step 826, the reversible motor 63 is stopped, and the process returns to step B1 to repeat the above-described operation. In this manner, when there is a request to change the selection of a developer during a copying operation, the developer to be used is switched at least after the development of the image being copied is completed. On the other hand, the step 82
In step 2, if the life of the developer is reached, step 82
Proceed to step 7. In step 827, it is checked whether there is another developer of the same color. If not, the process returns to step B4 and the above-described operation is repeated. If there is another developer of the same color, the process advances to step 828. In step 828, the developer of the same color is selected, and the process proceeds to step B25. In this way, when the developer in the developing device you are using reaches the end of its life,
If there is another developing device, that is, a developing device containing developer of the same color, switching to that developing device is performed preferentially.

Next, interrupt processing will be explained using the flowchart shown in FIG. This interrupt processing is set to be repeated at regular intervals. Once the interrupt processing is started, the process advances to step C1.

In step C1, it is checked whether the reversible motor 63 is rotating (the developing device is in operation), and if it is rotating, the process advances to step C2. In step C2, the integrated time meter 1391 or 1392 of the selected developing device is energized, and the process proceeds to step C3. In step C3, the A flag is "1"
It is checked whether it is "1" or not, and if it is not "1", the process advances to step C4. In step C4, timer A starts counting, and the process proceeds to step C5. In step C5, it is checked whether or not the timer A has counted 58 eO, and if it has counted 5 seconds, the process proceeds to step C6.

In step C6, the A flag is set to "1", and the process proceeds to step C7. In step C5 above, 5 se
If c has not been counted, the process jumps to step C6 and proceeds to step C7. On the other hand, if the flag is set to "1" in step C3, the process proceeds to step C8. In step C8, it is checked whether the developer concentration of the selected developer is lower than a predetermined value, based on the signal from the developer concentration detector 421 or 422 of the selected developer. If so, proceed to step C9.

In step C9, a developer replenishment operation is performed by driving the developer replenishment roller 521 or 522 of the selected developing device, and the process proceeds to step C7. Step C8 above
If the value is higher than the predetermined value, the process jumps to step C9 and proceeds to step C7. In this manner, after the start of the copying operation, a predetermined period of time (for example, approximately se
From c onwards, the concentration is checked based on the output of the developer concentration detectors 42s and 422. In step C7, the color selection key 15 on the operation panel is
6 is turned on, and if it is turned on, the process advances to step C10. In step C10, the color change request flag is set to 1", and the process proceeds to step C11. In step C7, if the color selection key 156 is not turned on, step C10 is jumped to, and step C
Proceed to step 11.

On the other hand, in step C1, the reversible motor 6
If 3 is not rotating, the process advances to step CI2. In step C12, the flag is set to 0'', timer A is reset, and power is turned off to the totalizing time meter 1391 or 1392, and the process proceeds to step C11. In step C11, a display request for the total number of copies (operation (entered in code using the numeric keypad 154 on the panel) is checked, and if there is a display request, step C1
Proceed to step 3. In step C13, the contents of the total number counter in the storage device 175 are transferred to the number display section 15 on the operation panel.
5 and proceeds to step c14. Above step C1
1, if there is no request to display the total number of copies, the process advances to step C15. In step C15, the first developing device 32
1 to display the number of copies made (numeric keypad 154)
If there is a display request, the process advances to step C16.

In step C16, the first developing device 3 in the storage device 175
The contents of the sheet number counter corresponding to No. 21 are displayed in the sheet number display section 155.
is displayed, and the process proceeds to step C14.

In step C15, if there is no display request, the process advances to step C17. In step C17, the second developing device 3
22 to display the number of copies made (numeric keypad 15)
4), and if there is a display request, the process advances to step 018. In step 018, the contents of the sheet number counter corresponding to the second developing device 322 in the storage device 175 are displayed on the sheet number display section 155, and the process proceeds to step C14. In step C17, if there is no display request, the process advances to step C19.

In step C19, the normal number of copies is displayed on the sheet number display section 155, and the process proceeds to step C14. In step C14, a request for clearing the number of copies for each developer (on the numeric keypad 154)
If there is no clear request, the interrupt process ends here, and if there is a clear request, the process proceeds to step C20. In step C20, the contents of the sheet number counter corresponding to the designated developer in the storage device 175 are cleared, and the interrupt processing is ended.

With the configuration described above, a color display is provided near the color selection key on the operation panel, and the result of color selection using the color selection key is displayed on the color display, so the user can Colors can be easily known, thereby preventing copying errors and improving operability.

Furthermore, since the color display does not display when the developer is not installed, it is easy to see that the developer is not installed, and the mistake of copying without the developer is eliminated. It also improves operability.

In the above embodiment, a case was explained in which the present invention is applied to a monochromatic color copying machine, but the present invention is not limited to this. The present invention can be applied to any image forming apparatus that forms an image using a developing device.

[Effects of the Invention] As detailed above, according to the present invention, a plurality of developing devices capable of developing different colors are selected from among a plurality of developing devices, and the installed developing device is installed in the main body of the image forming apparatus. In an image forming apparatus that can form an image of a desired color on an image forming medium using At the same time, it detects whether or not the developing device is installed in the image forming apparatus main body, and the above color is not displayed when the developing device is not installed, so the color of the image formed can be changed. It is possible to provide an image forming apparatus in which the image forming apparatus can be easily determined, image formation without a developing device can be prevented, and operability can be improved.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a schematic configuration diagram of a color copying machine, Fig. 2 is a schematic vertical side view of a developing device, and Fig. 3 shows different operating states of the developing device. 4 to 6 show the configuration of the driving force transmission system, FIG. 4 is a front view showing the meshing state of the gear group, and FIG. 5 is a cross-sectional view showing the developed state. 6 is a sectional view showing the state of driving force transmission to the drive gear, FIG. 7 is a partially sectional plan view of the magnetic roll driving means, and FIG. 8 is a side view of the magnetic roll driving means. 9 is an explanatory diagram showing the operating state of the magnetic roll driving means, FIG. 10 is a schematic perspective view of the developing device section, FIG. 11 is a plan view showing the top surface of each developing device, and FIG.
Figure 2 is a front view showing the fixing bridge and structure of the developer, Figure 13 is an explanatory diagram showing the relationship between the handle and the hook, Figure 14 is a plan view of the operation panel, and Figure 15 is the overall control. FIG. 16 is a block diagram schematically showing the circuit; FIG.
FIG. 7 is a flowchart for explaining the operation when the power is turned on, FIG. 18 is a flowchart for explaining the copying operation, and FIG. 19 is a flowchart for explaining the interrupt processing operation. Pl, P2... Paper, 1... Copying machine body, 2...
Document table, 7... Photosensitive drum, 10... Developing device,
321° 322...Developer, 156...Color selection key, 157-160...Color display, 171...Microcomputer, 187s. 1872...Developer presence/absence signal generation means, 1881°1
882...Identification information generation means. Applicant's agent Patent attorney Takehiko Suzue Figure 7 Figure 8 Figure 1 υ Figure 9 (a) (b) Figure 11 (a) (b) Figure 16 Figure 17 Figure 17 (C) Figure 18 Figure (a) Figure 17 (d) Figure 18 Figure 19 (a)

Claims (4)

[Claims] (1) Select from a plurality of developing devices, each capable of developing a different color, and install it in the main body of the image forming apparatus, and use this installed developing device to form an image of a desired color on the image forming medium. In an image forming apparatus capable of performing image forming apparatus, an identification means for identifying the color of a developing device installed in the main body of the image forming apparatus, a display means for displaying the color of an image formed according to the identification result of the identification means, and a developing device. a detection means for detecting whether or not a developing device is attached to the main body of the image forming apparatus; and a control means for prohibiting the display means from displaying colors when the detection means detects that the developing device is not attached. An image forming apparatus comprising: (2) Multiple developing devices can be attached to the image forming device main body,
2. The image forming apparatus according to claim 1, wherein a display means displays the color of the developing device to be used from among the plurality of installed developing devices. (3) The control means, when the detection means detects that the developing unit is not installed, prohibits the display means from displaying colors and at the same time prohibits the image forming operation. The image forming apparatus according to scope 1. (4) The image forming apparatus according to claim 1, wherein the display means is provided in an operation section for performing an image forming operation.