JPH08146701A - Image forming device - Google Patents

Abstract

PURPOSE: To prevent the occurrence of a failure such as a miscopy by automatically deciding a cartridge to be in a developing position, for automatically detecting the fact that the cartride not to be in an exchange position is therein as soon as possible, in a rotary developing device. CONSTITUTION: In this image forming device constituted in such a manner that the rotary developing device having plural toner cartidges 23 which house the toner are annularly arrayed around a fitting part is arranged in the vicinity of a latent image carrier and rotated around the fitting part, to displace the arbitrary toner cartridge 23 to a developing position facing the latent image carrier and attain development and each toner cartridge 23 is freely attachably/ detachably arranged in the fitting part, at least, a part of the case of the cartridge 23 is made of a light transmissible material and a control part discriminating whether an abnormal operation in a cartridge switching operation in printing sequence is present or not, based on the color detected by a cartridge color detecting means 24 detecting the color of the toner housed in the cartridge 23 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner cartridge of a developing device used in an electrophotographic image forming apparatus such as a copying machine, a printer, a facsimile or the like, which can detect the toner cartridge type and toner color with a simple structure. Specifically, a rotary developing device, which is formed by arranging a plurality of toner cartridges containing a powder developer in a ring shape around a rotation shaft, is arranged in the vicinity of a latent image carrier, and the rotation type developing device is rotated about the rotation shaft. By rotating the developing device to displace an arbitrary toner cartridge to a developing position facing the latent image carrier to perform development, the color of the toner cartridge located in the housing of the image forming apparatus, and The present invention relates to an image forming apparatus capable of automatically detecting a remaining amount with high accuracy.

[0002]

2. Description of the Related Art In an image forming apparatus utilizing an electrophotographic process such as a copying machine, a printer and a facsimile machine, a photoconductor (latent image carrier) in which image information such as reflected light of a document is uniformly charged in advance. An electrostatic latent image is formed by irradiating the electrostatic latent image onto the recording paper, and a toner image obtained by adhering toner to the electrostatic latent image from a developing device is transferred onto the recording paper and then fixed to form an image. Is going. Traditionally,
Each latent image formed by exposing the latent image carrier surface with the color-separated light image is developed with a complementary color toner of the color-separated light,
A full-color image forming apparatus that adopts a method of transferring multiple toner images obtained by superimposing them on the same transfer paper, or an image to be reproduced in different colors is separately exposed on the latent image carrier, and each latent image formed is exposed. 2. Description of the Related Art There is known a multicolor image forming apparatus or the like that develops images with developers of different colors, and superimposes a plurality of obtained toner images on the same transfer paper. These image forming apparatuses require a plurality of developing devices for developing a plurality of colors. However, if the developing devices are individually configured and arranged side by side around the latent image carrier, the size of the device increases. There was a drawback.

Therefore, conventionally, a rotary member is disposed so as to be close to the latent image carrier, and a plurality of developing devices are sequentially assembled in an annular shape along the circumferential direction with respect to the rotary member, so that each developing device is mounted. A rotary developing device has been developed in which a latent image on a latent image carrier is developed with toner of each color by sequentially conveying the latent image carrier to a developing position facing the latent image carrier. As such a rotary type developing device, an actual developing machine 62
In Japanese Patent Laid-Open No. 116263, a color mark representing the color of the developer accommodated in each unit is attached to the surface of the case of each of the plurality of developing units, and the color mark is attached to the developing unit. A configuration in which a light transmitting portion is provided in the main body of the image forming apparatus is disclosed. However, when the color mark is attached, it is impossible to visually check the inside of the case of the developing unit from the outside of the machine, and the case of the developing unit is opened after opening the door of the casing of the image forming apparatus. Therefore, it is impossible to know the remaining amount simply and quickly.

In Japanese Patent Laid-Open No. 62-67571, the side wall of the toner hopper is made of a transparent plate coated with an antistatic agent so that the remaining toner consumption can be visually confirmed. A configuration is disclosed in which toner can be replenished and a clear copy of an image with no decrease in density is always obtained. However, this conventional example is not related to the rotary type developing device, and further, since consideration is not given to providing a light-transmitting portion or the like on the housing side of the image forming apparatus so that it can be seen from outside the machine, the remaining amount is In order to know, the complicated work of opening the doors and the like of the housing one by one was required.

In each of the above-mentioned conventional examples, since the color and the remaining amount of toner are visually confirmed, not only the confirmation work is complicated, but also misidentification due to a mistake is likely to occur.
There was a problem of lack of reliability. From such a point, as in the technique described in Japanese Patent Laid-Open No. 60-52878, the developing unit is provided with an identification protrusion, and the identification protrusion is detected by a photocoupler to automatically detect the color of the development unit. A method has also been proposed, but in this method, it is necessary to separately prepare the identification protrusion for each color toner cartridge, or in the cartridge of the type that refills the toner for reuse of the container, refilling At times, there was a problem such as making a mistake in the combination of the cartridge and the toner color.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and a plurality of toner cartridges containing toners of different colors are annularly arranged on the outer periphery of a developing device and each toner cartridge is rotated by the rotation of the developing device. In an electrophotographic image forming apparatus having a structure for selectively moving to and stopping at a developing position (a position facing a photosensitive member), two side walls and an inside of a cartridge made of a light-transmissive material are opposed to each other. The light emitting portion and the light receiving portion are arranged so as to face each other across the accommodation space, and R, G,
Since the toner color accommodated is determined based on the spectral distribution of the received light obtained when the detection light of B is emitted, the cartridge that should be in the developing position can be automatically determined. An object of the present invention is to provide an image forming apparatus that can automatically and quickly detect that a cartridge that should not be in the replacement position is in the replacement position, and that can prevent problems such as miscopy from occurring. Further, it is possible to promptly notify the operator of the occurrence of an abnormality in the cartridge switching operation to prompt an appropriate recovery operation. The color detection of the cartridge can be realized without making a substantial physical modification to the cartridge. Further, although the light emitting section constituting the cartridge color detecting means has a light source of a plurality of wavelengths, since the respective light sources are arranged at one point as much as possible, it is possible to eliminate the variation in the optical path of each detection light and improve the reliability of detection. . If a single light source such as a white sphere is used and a filter having different spectral characteristics is used to irradiate detection light having wavelengths of R, G, and B colors, variations in the optical path can be completely eliminated. it can. Further, in a light source using a plurality of LEDs, the LEDs are arranged in the horizontal direction so as to be parallel to the upper surface of the toner in the cartridge, so that the toner end can be detected with high reliability.

[0007]

In order to achieve the above object, the present invention provides a rotary developing device in which a plurality of toner cartridges containing toner are annularly arranged around a mounting portion in the vicinity of a latent image carrier. By rotating the rotary developing device about the mounting portion, any toner cartridge is displaced to a developing position facing the latent image carrier to perform development, and each toner cartridge is attached to or detached from the mounting portion. In the freely arranged image forming apparatus, at least a part of the case of the toner cartridge is made of a light transmissive material, and based on the color detected by the cartridge color detecting means for detecting the color of the toner stored in the toner cartridge. And a control unit for determining whether or not there is an abnormal operation of the cartridge switching operation on the print sequence. When the control section finds an abnormal operation of the cartridge switching operation on the print sequence based on the toner color detected by the cartridge color detecting means,
It is characterized by executing a display mode for displaying an abnormal message on the display means.

The cartridge color detecting means includes at least two light emitting portions having different spectral characteristics for identifying the spectral characteristics of each color toner, and a light receiving portion for receiving light emitted from each light emitting portion. The control unit is characterized in that the color of the toner is determined based on a change in the amount of light having different spectral characteristics received by the light receiving unit. The light emitting portion and the light receiving portion forming the cartridge color detecting means are respectively disposed outside the light transmissive side walls of the toner cartridge which face each other, and at least a part of the light emitted from the light emitting portion is provided on the outer wall of the cartridge. It is characterized in that the light is received by the light receiving portion by transmitting the light inside the wall.

The plurality of light emitting portions having different spectral characteristics, which constitute the cartridge color detecting means, are concentrated at one point as much as possible. The cartridge color detecting means includes a light emitting section which is a single light source, a light receiving section which receives light from the light emitting section, and a filter which is interposed between the light emitting section and the light receiving section. It is characterized in that it comprises a filter portion having a spectral characteristic, and is configured so that each filter portion can be selectively switched and arranged on the optical path. The filter is supported by a movable member, and is configured to move each filter portion onto the optical path by operating the movable member.

The plurality of light emitting portions having different spectral characteristics are arranged in a concentrated manner as much as possible and are arranged in the horizontal direction. The plurality of filters having different spectral characteristics are arranged on the transparent side wall of the toner cartridge, and the filter located on the optical path of the detection light from the light emitting unit can be changed by moving the toner cartridge. It is characterized by being. The cartridge color detecting means is provided with a function of detecting the toner end in the cartridge.

[0011]

First, since the color of the toner in the transparent cartridge is detected by the cartridge color detecting means to determine the abnormal operation of the cartridge switching operation in the print sequence, the switching operation of the developing unit is performed. Anomalies can be detected early and damage to other parts can be prevented. When the cartridge color is detected by the cartridge color detecting means and an abnormal operation of the cartridge switching operation in the print sequence is confirmed, the display means has a display mode for displaying an abnormal message. Notify the user of the occurrence and enable proper recovery operation. The cartridge color detection means uses light having at least two spectral characteristics capable of identifying the spectral characteristics of each toner, and determines the difference in the spectral characteristics of the toner by the change in the light amount of the spectral characteristics of the light receiving unit. By doing so, it is possible to identify the toner color without physically modifying the cartridge.

The light emitting portion and the light receiving portion of the cartridge color detecting means are arranged at the end portion of the cartridge, and at least a part of the light emitted from the light emitting portion is guided to the inside of the wall thickness of the bottom plate of the cartridge and then received. Therefore, the toner color can be identified without physically modifying the cartridge. As the light emitting parts, LEDs having different spectral characteristics are arranged so as to be concentrated at one point as much as possible, so that the light emitting sources of a plurality of wavelengths are integrated and the variation in the optical path of the detection light can be reduced. Since the light from a single light source is transmitted by sequentially switching filters having different spectral characteristics, it is possible to reduce variations in the optical path of the light.

Since LEDs of a single light source having different spectral characteristics are arranged side by side in the horizontal direction as much as possible, by arranging light emitting sources of a plurality of wavelengths horizontally, it is possible to reduce variations in the optical path of light. The toner end can be detected accurately. Since the filter is attached to the movable member, and the emitted detection light is sequentially switched and transmitted, the variation in the optical path of the light can be reduced. Since the plurality of filters are attached to the side wall of the toner cartridge with the positions thereof shifted, the spectral characteristics of the transmitted light can be changed by displacing the toner cartridge by a predetermined angle, and variations in the optical path of the light can be reduced. Since the cartridge color detecting means also has a cartridge toner end detecting function, the function can be improved with a simple configuration.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings. FIG. 1 is a schematic diagram showing the overall configuration of an embodiment of a color image forming apparatus to which the present invention is applied. Reference numeral 1 is a flexible belt-shaped photoreceptor as a belt-shaped image carrier, and the belt-shaped photoreceptor Reference numeral 1 is stretched endlessly by rotating rollers 2 and 3, and is rotated clockwise by driving the rotating rollers. Reference numeral 4 is a charging member serving as a charging means, 5 is a laser writing system unit serving as an image exposing means, and 6 to 9 are a plurality of developing means, that is, developing devices each containing a developer of a specific color. The laser writing system unit 5 is housed in a holding housing having a slit-shaped exposure opening on the upper surface and incorporated in the apparatus body. As the laser optical system 5, in addition to the optical system shown in the figure, an optical system in which a light emitting section and a converging optical transmission body are integrated can be used. The charging member 4, the laser writing unit 5D, and the photoconductor cleaning device 15 are provided on one roller 2 of the plurality of rollers 2 and 3 around which the belt-shaped photoconductor 1 is installed.

The developing units 6, 7, 8 and 9 contain, for example, yellow, magenta, cyan, and black developers, respectively, and each developing unit has the belt-shaped photosensitive member when it is in a predetermined developing position. Each developing sleeve 6a, 7a, 8a, 9 for applying a developer in close proximity to or in contact with the body 1
a has a function of developing an electrostatic latent image on the photosensitive belt 1 by a non-contact developing method or a contact developing method. Reference numeral 10 denotes an intermediate transfer belt as a transfer image carrier. The intermediate transfer belt 10 is stretched endlessly by rotating rollers 11 and 12 and is conveyed counterclockwise by driving the rotating rollers. The belt-shaped photoreceptor 1 and the intermediate transfer belt 10 are in contact with each other at a position corresponding to the outer peripheral surface of the rotating roller 3, and the first visible image on the belt-shaped photoreceptor 1 is provided in the intermediate transfer belt. Bias roller 13
Is transferred onto the intermediate transfer belt 10. Then, by repeating the same process, the second-time visible image, the third-time visible image, and the fourth-time visible image are overlapped on the intermediate transfer belt 10, and no positional deviation occurs. Thus, the image is transferred onto the intermediate transfer belt 10. Reference numeral 14
Is a transfer roller 14, and the proper position of the intermediate transfer belt 10,
For example, it is arranged in the outer peripheral position of the roller 11 so as to be freely contactable and separable. Reference numeral 15 is a cleaning blade as a cleaning device for the belt-shaped photoreceptor 1, 16 is a cleaning device for the intermediate transfer belt 10, and the blade 16A of the cleaning device 16 is located at a position apart from the surface of the intermediate transfer belt 10 during image formation. The surface of the intermediate transfer belt 10 is pressed against the surface of the intermediate transfer belt 10 as shown in the figure only during cleaning after the image transfer.

A color image forming process by the color image forming apparatus is performed as follows. First, the formation of a multicolor image by the apparatus of this embodiment is performed by inputting a color signal output from an image reading apparatus separate from the image forming apparatus into a laser optical system of the image forming apparatus. Is performed according to the following imaging system. That is, after the photoelectric conversion data obtained by scanning the original image with the image sensor by the color image data input section equipped with the image sensor is digitized, the image data processing section performs arithmetic processing to obtain the required image. Data is created and is temporarily stored in the image memory. The image memory is then
It is taken out at the time of recording and is output to the recording unit, for example, the color image forming apparatus shown in FIG.

When a color signal output from an image reading apparatus separate from the image forming apparatus is input to the laser writing system unit 5, the laser writing system 5 produces a laser beam generated by a semiconductor laser (not shown). Is rotated and scanned by the polygon mirror 5B rotated by the drive motor 5A, the optical path is bent by the mirror 5F through the fθ lens 5C, and the charge is removed in advance by the charge removal lamp 21 and then uniformly by the charging member (charging means) 4. The charged surface of the belt-shaped photoreceptor 1 is exposed to light and an electrostatic latent image is formed. Here, the image pattern to be exposed is a monochromatic image pattern when the desired full-color image is separated into yellow, magenta, cyan, and black. Each electrostatic latent image formed corresponding to each color is developed by a rotary developing device with a yellow, magenta, cyan, and black developing device, and each color is visualized and monochromatic to form a monochromatic image. It
The monochromatic image formed on the belt-shaped photoreceptor 1 is transferred onto the intermediate transfer belt 10 which rotates counterclockwise while contacting the belt-shaped photoreceptor 1. Subsequently, the yellow, magenta, cyan, and black single-color images formed on the photoconductor belt 1 are sequentially superposed on the surface of the intermediate transfer belt 10. The images of yellow, magenta, cyan, and black superimposed on the intermediate transfer belt 10 are fed from the paper feed table 17 to the paper feed roller 1.
8, the transfer roller 14 transfers the transfer paper P onto the transfer paper P that has been conveyed to the transfer portion via the registration roller 19. After the transfer is completed, the transfer paper P is fixed by the fixing device 20 to complete a full-color image. The intermediate transfer belt and the photoreceptor belt are seamless.

Next, FIG. 2 shows a perspective view of the rotary developing device mounted in the present color image forming apparatus. This rotary developing device is configured to switch the color to be developed between black, yellow, magenta, and cyan by rotating, and cartridges 23K, 23Y, and 23 of each color
The toner in M and 23C is detected by the detection sensor 24. Each of the developing devices 6, 7, 8 and 9 described above has 9
The cartridges are arranged at 0 degree intervals, and each cartridge is annularly arranged at the outer peripheral position of the mounting portion at one end of the rod-shaped portion (rotating shaft). The cartridges of the respective colors correspond to the developing devices of the respective colors and communicate with each other.

FIG. 3 (a) is a schematic structural explanatory view of an example of the cartridge color detecting means, and FIG. 3 (b) is a schematic view showing a transmission state of detection light. Detection sensor (cartridge color detection means)
24 has a structure in which a light emitting portion 25 and a light receiving portion 26 are arranged so as to face each other at two free ends of a U-shaped support member 24a, and both wall surfaces 2 of the cartridge 23 that face each other are opposed to each other.
It is attached so as to sandwich 3a and 23b. The detection sensor 24 can also be used for detecting the toner end, and in this case, the toner surface 27 is detected by the detection sensor 2.
The light emitting unit 25
Since the light from the light reaches the light receiving unit 26, the toner end can be detected.

As the material of the cartridge 23 of this embodiment, PC (polycarbonate) having high light transmittance is used. Since the light emitting portion 25 and the light receiving portion 26 are arranged at positions near the end portions of the wall surface, as shown in FIG. 3 (b), the light from the light emitting portion 25 is the light 28a which goes straight to the light receiving portion 26 and the cartridge bottom plate ( Light 28b is transmitted through the inside of the wall thickness of the outer wall 23c and enters the light receiving portion 26. The light 28b
The outer wall through which is passed is not limited to the bottom plate, and may be another side wall.

FIGS. 4 (a), (b), (c) and (d) are diagrams showing the spectral distributions of the toners of the respective colors and the detection light. FIG.
(b) shows the spectral distribution of magenta, and (c) shows the spectral distribution of cyan toner. In this embodiment, yellow, magenta, and cyan are used as color toners, and black toner is further added.
It has a color configuration. As is clear from FIG. 3A, the yellow toner well absorbs blue (B) light, but reflects green (G) red (R) light. Similarly, (b)
The magenta toner shown in (G) absorbs light well (B),
The (R) light is reflected, the cyan toner shown in (c) absorbs the (R) light well, and the (G) light is reflected. For this reason,
For example, when the detection sensor 24 is used to detect the yellow toner cartridge 23Y, first, the light emitting unit 25 is used.
When the amount of toner is sufficient when blue light is emitted from one of the LEDs that make up (when at least the top surface of the toner is located above the optical path connecting the light emitting unit and the light receiving unit). Most of the emitted blue light is absorbed by the toner, and the only blue light that can reach the light receiving unit 26 is the light 28b that passes through the inside of the cartridge bottom plate 23c (translucency). However, since the blue light is easily absorbed by the yellow toner that is in contact with the translucent bottom plate 23c, the blue light is attenuated while being transmitted through the cartridge bottom plate, and does not reach the light receiving unit 26.

Next, if the amount of toner is sufficient and the green light is emitted from the other LEDs constituting the light emitting section 25, the yellow toner in the cartridge will reflect the green light, so that it will propagate in the bottom plate 23c. The green light that arrives reaches the light receiving unit 26 with almost no attenuation. Red light is not attenuated at all, and light receiving section 2
Reach 6. Therefore, it is possible to determine that the toner cartridge is yellow toner based on the received light amounts of the three color lights. Similarly, the magenta toner attenuates only the green light and the cyan toner attenuates only the red light, so that the toner color can be determined based on the kind of the light that causes the attenuation. As shown in (d), in the case of black toner, all three colors are attenuated, so if all three colors are attenuated, it is determined to be black. When the toner is exhausted, all the three colors of light reach the light receiving portion directly, and therefore all three colors should not be attenuated. If all three colors are not attenuated, it is determined as toner end.

In FIG. 2, the cartridge 23Y at the detection position by the detection sensor 24 is not at the developing position (position facing the belt-shaped photosensitive member 1 in FIG. 1) but in the developing position in FIG. The cartridge 2
It is 3K. Strictly speaking, the developing position is not the cartridge 23K but the developing device (black developing device) at the same circumferential position as the cartridge 23, but in the sense that it is at the position corresponding to the developing position. In the cartridge. In FIG. 2, reference numeral 6a indicates that
It is a developing roller of a black developing device.

Therefore, the detection sensor 24 does not directly detect the toner color of the cartridge at the developing position, but the detected cartridge is provided on the assumption that the cartridge next to the detected cartridge is at the developing position. It is determined that the cartridge located at the rear (or front) position in the rotational direction by one unit is at the developing position. It is the CPU, R that makes various judgments based on the above detection results.
A control unit (not shown) including an OM, a RAM, an I / O port, and the like.

FIG. 5 shows a print sequence. In step 100, the black toner cartridge 23K is set at the developing position by operating a key on an operation unit (not shown). At this time, the yellow cartridge 23Y should be located at a position corresponding to the detection sensor 24, and color detection is performed at this position (step 101). If there is no abnormality in color detection (such as when a cartridge other than yellow is detected), the black cartridge 2 is placed at the developing position.
Since 3K is positioned, the black plate surface is printed with the black toner from the black cartridge 23K in step 102. Next, in step 103, the cyan toner cartridge is moved to the developing position. At this time, the sensor 24 detects the color of the adjacent black cartridge. If there is no abnormality in the color detection in step 104 (if a black cartridge is detected), it means that the cyan cartridge is located at the developing position, so the cyan plate surface is printed in step 105.
Next, in step 106, the magenta toner cartridge is set to the developing position, and the sensor 24 detects the color of the adjacent cyan cartridge. If there is no abnormality in the color detection in step 107, the magenta printing plate is printed in step 108. Next, in step 109, the yellow toner cartridge is set at the developing position, and the sensor 24 detects the color of the adjacent magenta cartridge. Step 1
If there is no abnormality in the color detection of 10, the yellow plate is printed in step 111.

FIG. 6 shows a color detection sequence. Here, it is assumed that various displays on the display unit such as the operation unit of the image forming apparatus are controlled based on control signals from the control unit. That is, in step 200, the toner color of the cartridge at the detection position is detected, and in step 20
In step 1, it is determined whether or not the toner color is the toner color of the cartridge that should have been originally set at the detection position. If there is no color consistency, a message of sequence abnormality is displayed on the display panel in step 202. To do. Step 2
If the color matching is completed in 01, it is determined in step 203 whether the toner is out. If it is toner end, a toner end message is displayed on the display panel in step 204. If it is not the toner end, the color detection routine is ended.

FIG. 7 shows a detection timing chart. First, the stepping motor is driven to set the black toner cartridge to the developing position for black printing. When set, emit red light. The light emission is 38 KHz burst light for 4 ms.
Then, after stopping for 4 ms, green light is emitted. Similarly, after 4 ms, blue light is emitted. The light receiving section 26 detects this light, and the control section makes color judgment based on the above-mentioned criteria. When the process of the next color plate is started, the stepping motor is driven to set the toner cartridge of the relevant color to the developing position. In this case as well, color detection is similarly performed using red light, green light, and blue light.

FIG. 8 shows a block diagram of the detection circuit of the present invention. The square wave oscillating circuit 30 generates a square wave of 38 KHz, and the following AND gate 31a constitutes a control unit C.
LED driver 32 by R gate signal from PU41
Perform R gate. Similarly, the LED driver 32G, 3 is generated by the G gate signal and the B gate signal from the CPU 41.
2B is selected and driven. The light emitted from each of the LEDs 33R, 33G, and 33B (having different spectral characteristics) forming the light emitting unit 25 passes through the toner cartridge 23, at least a part of which is made of a transparent material, and the light receiving sensor 34 (the light receiving unit 26). ). Light receiving sensor 3
The signal that enters 4 and is photoelectrically converted is amplified by the amplifier 35,
After the limit is adjusted by the limiter 36, only the 38 KHz signal is selected by the pan pass filter 37. After that, the signal is demodulated by the demodulator 38, integrated by the integrator 39, and then, when the signal becomes equal to or higher than a predetermined threshold level according to the comparison judgment in the comparator 40, it becomes High.
The h signal is output. The output signal is input to the CPU 41 and used for discrimination. When an abnormality occurs, such as when the detected toner color is different from the expected color, a display is made on the display unit 42. The LEDs 33R, 33 having different spectral characteristics
G and 33B are arranged so as to concentrate on one point as much as possible in order to prevent variations in the optical path.

FIG. 9 is a structural explanatory view of an embodiment of the cartridge color detecting means (detection sensor) used in the present invention.
A characteristic is that a filter 50 is arranged in the optical path of the light emitting part 25 and the light receiving part 26 which are arranged opposite to each other with the cartridge 23 sandwiched between them. It is a disk-shaped filter that rotates while being supported by its part.
Three filters 52R, 52G, 52B having R, G, B and spectral characteristics for each color are arranged at 0 degree intervals,
By rotating the shaft 51a rotated by the motor 51, the filters located on the optical path can be sequentially switched. Note that white light is used as a light source forming the light emitting unit 25. According to this embodiment, the light emitting unit 25 is used as a single light source, and the light from this light source is transmitted through filters having different spectral characteristics, so that R,
Since the G and B detection lights are obtained, not only the toner color detection capability similar to that of the above-described embodiment is exhibited, but also the single light source can prevent the occurrence of the variation of the optical path. The disc-shaped frame that supports the filter constitutes a movable member.

FIG. 10 shows another embodiment of the light emitting section, in which R, G, and B filter seals 60R, 60B are provided at appropriate positions on the side plate 23a of the toner cartridge 23 made of a light transmitting material.
60G and 60B are attached, and the rotation angle of the cartridge is adjusted so that each filter seal can be sequentially positioned on the optical path of the detection light from the light emitting unit 25 as a single light source by the rotation of the developing device. By sequentially changing the amount by a minute, the light source light is narrowed down by the aperture 65 while the filter seals for the respective colors are sequentially stopped on the optical path, and then transmitted through the respective filters to be detected by the light receiving unit 26. White light is used as the light source 25. The data processing procedure after light reception is the same as that in the above-mentioned embodiment.

FIG. 11 is a diagram showing a main part of another embodiment of the light emitting section, in which the light emitting elements inside the LEDs constituting the light emitting section 25 are R, G, B light emitting elements 70R, 70G, 7 respectively.
There are 0B, and by making these selectively emit light,
Detect the toner color of the cartridge. The detection procedure is the same as in each of the above embodiments.

FIG. 12 is a schematic view showing an embodiment of an arrangement example of LEDs constituting the light emitting section. By arranging the single color R, G, B light emitting LEDs 70R, 70G, 70B in one point as much as possible and aligning them in the horizontal direction, it is possible to form a row parallel to the upper surface of the toner T in the cartridge 23. Therefore, the remaining amount can be accurately detected.

[0033]

As described above, according to the present invention, a plurality of toner cartridges accommodating toners of different colors are annularly arranged on the outer periphery of the developing device, and the developing device is rotated to move the toner cartridges to the developing position ( In an electrophotographic image forming apparatus having a structure for selectively moving and stopping at a position facing a photoconductor), two side walls facing each other of a cartridge made of a light-transmissive material and an accommodation space inside Across the
Since the light emitting portion and the light receiving portion are arranged so as to face each other and the toner color accommodated is determined based on the spectral distribution of the received light obtained when the detection light of R, G, B is emitted, it is at the developing position. You can automatically determine which cartridge should be,
As a result, it is possible to automatically and promptly detect that the cartridge, which should not be in the exchange position, is in the exchange position, and it is possible to prevent a problem such as a miscopy from occurring.

Further, it is possible to promptly notify the operator of the occurrence of an abnormality in the cartridge switching operation to prompt an appropriate recovery operation. The color detection of the cartridge can be realized without making a substantial physical modification to the cartridge. Further, although the light emitting section constituting the cartridge color detecting means has a light source of a plurality of wavelengths, since the respective light sources are arranged at one point as much as possible, it is possible to eliminate the variation in the optical path of each detection light and improve the reliability of detection. . In addition, by using a single light source such as a white sphere and using filters having different spectral characteristics, R,
By irradiating the detection light having the wavelength of each color of G and B, the variation of the optical path can be completely eliminated. Further, in a light source using a plurality of LEDs, the LEDs are arranged in the horizontal direction so as to be parallel to the upper surface of the toner in the cartridge, so that the toner end can be detected with high reliability.

[Brief description of drawings]

FIG. 1 is an overall configuration explanatory diagram of an example of an image forming apparatus to which the present invention is applied.

FIG. 2 is a perspective view showing the configuration of an example of a rotary developing device to which the detection sensor of the present invention is applied.

3A is a perspective view showing a configuration of an example of a cartridge color detection unit, and FIG. 3B is a sectional view showing a detection state.

FIG. 4A, FIG. 4B, FIG. 4C, and FIG. 4D are diagrams showing the spectral distribution of detection light for each color toner.

FIG. 5 is a flowchart showing a print sequence.

FIG. 6 is a diagram showing a color detection sequence.

FIG. 7 is a detection timing chart.

FIG. 8 is a diagram showing a circuit configuration of an example of a cartridge color detection unit of the present invention.

FIG. 9 is a structural explanatory view of another embodiment of the cartridge color detecting means of the present invention.

FIG. 10 is a structural explanatory view of another embodiment of the cartridge color detecting means of the present invention.

FIG. 11 is a structural explanatory view of another embodiment of the cartridge color detecting means of the present invention.

FIG. 12 is a structural explanatory view of another embodiment of the cartridge color detecting means of the present invention.

[Explanation of symbols]

1 photoconductor belt, 2, 3 rotation roller, 4 charging roller, 5 laser writing system unit, 5A drive motor, 5B polygon mirror, 5C fθ lens, 5D
Laser writing, 6 Y developing unit, 7 M developing unit, 8 C developing unit, 9 black developing unit, 1
0 intermediate transfer belt, 11, 12 rotating roller, 13
Bias roller, 14 Transfer roller 15 Cleaning device for photoconductor belt, 16 Cleaning blade for intermediate transfer belt, 16A Cleaning blade, 16B
Cleaning blade support member, 17 paper feed table, 18
Paper feed roller, 19 upper registration roller, 20 fixing device, 23, 23K, 23Y, 23M, 23C toner cartridge, 23a, 23b wall surface, 24 detection sensor (cartridge color detection means), 24a support member, 25
Light emitting part, 26 Light receiving part, 27 Toner surface, 28a, 2
8b light, 30 square wave oscillator circuit, 31 AND gate, 32 LED driver, 33 LED, 34 light receiving sensor, 35 amplifier, 36 limiter, 37 bandpass filter, 39 integrator, 40 comparator, 41 C
PU, 42 display unit, 50 filter, 51 motor,
52 filter, 60 filter seal.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location G03G 21/00 370 (72) Inventor Kenji Shinohara 1-3-6 Nakamagome, Ota-ku, Tokyo Stocks Inside Ricoh Company (72) Inventor Yutaka Shio 10-3 Kitamura, Tottori City, Tottori Prefecture Inside Ricoh Micro Electronics Co., Ltd.

Claims (10)

[Claims] 1. A rotary developing device, in which a plurality of toner cartridges containing toner are annularly arranged around a mounting portion, is arranged near a latent image carrier, and the rotary developing device is centered around the mounting portion. In an image forming apparatus in which an arbitrary toner cartridge is rotated to displace to a developing position facing the latent image carrier to perform development, and each toner cartridge is detachably arranged in the mounting portion, At least a part of the case of the toner cartridge is made of a light-transmitting material, and the abnormality of the cartridge switching operation in the print sequence is based on the color detected by the cartridge color detecting means for detecting the color of the toner stored in the toner cartridge. An image forming apparatus having a control unit for determining whether or not there is an operation. 2. The control unit causes the display unit to display an abnormal message when an abnormal operation of the cartridge switching operation in the print sequence is found based on the toner color detected by the cartridge color detection unit. The image forming apparatus according to claim 1. 3. The cartridge color detecting means includes at least two light emitting portions having different spectral characteristics for identifying the spectral characteristics of the toner of each color, and a light receiving portion for receiving light emitted from each light emitting portion. 2. The control unit determines the toner color based on a change in the amount of light having different spectral characteristics received by the light receiving unit.
Or the image forming apparatus according to 2. 4. The light emitting portion and the light receiving portion which constitute the cartridge color detecting means are arranged outside the light transmitting side walls of the toner cartridge which face each other, and at least one of the light emitted from the light emitting portion is disposed. 4. The image forming apparatus according to claim 3, wherein the light receiving portion receives light by allowing the portion to pass through inside the outer wall of the cartridge. 5. The plurality of light emitting portions having different spectral characteristics, which constitute the cartridge color detecting means, are centrally arranged at one point as much as possible.
Alternatively, the image forming apparatus according to item 4. 6. The cartridge color detecting means comprises a light emitting portion which is a single light source, a light receiving portion which receives light from the light emitting portion, and a filter which is interposed between the light emitting portion and the light receiving portion. 2. The filter is composed of filter portions having different spectral characteristics, and each filter portion is configured to be selectively switched on the optical path.
Or the image forming apparatus according to 2. 7. The image according to claim 6, wherein the filter is supported by a movable member, and the filter member is configured to be moved to the optical path by operating the movable member. Forming equipment. 8. The plurality of light emitting portions having different spectral characteristics are arranged as concentrated as possible and arranged in the horizontal direction.
Alternatively, the image forming apparatus according to item 7. 9. A plurality of the filters having different spectral characteristics are arranged on a light-transmitting side wall of the toner cartridge, and the filter is positioned on the optical path of the detection light from the light emitting portion by moving the toner cartridge. 7. The image forming apparatus according to claim 6, wherein the image forming apparatus is configured to be changeable. 10. The image forming apparatus according to claim 1, wherein the cartridge color detection unit has a function of detecting a toner end in the cartridge.