JPH02163769A - Color image forming device - Google Patents

Abstract

PURPOSE:To attain high picture quality copying continuously within a practical cost range by employing a process cartridge for color image formation, and replacing a cartridge type developing device according to toner consumption. CONSTITUTION:The image carrier 120, electrostatic charger 121, Y developing device 152, M developing device 126, C developing device 127, and cleaning device 129 of the color image forming device are incorporated in the process cartridge 130. Developing devices 125 - 127 are unitized and put in respective toner chambers 155 - 157 replaceably, and rest detectors 165, 166, and 167 are arranged in the respective chambers. A CPU 215 makes an LED display device illuminate according to the toner rest amounts and copy quantities of the respective chambers to indicate the replacement of a specific developing device. Consequently, the cost is prevented from increasing and high picture quality can be maintained for a long period.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color process cartridge that is detachable from an apparatus main body and is disposable depending on the usage limit, and particularly relates to the process cartridge 7: The present invention also relates to a color image forming apparatus in which a plurality of developing devices incorporated in the process cartridge are individually replaceable in response to toner consumption.

[Conventional technology]

In conventional electrophotographic copying machines and the like, the image forming means involved in image formation wears out and deteriorates as it is used, and reaches the limit of its use at a slow speed. Generally, on the user side, it is difficult to judge the usage limit of the image forming means, so that an unreasonable copying operation exceeding the limit is performed. As a result, the copy quality is always unstable, the service work on the manufacturer's side becomes complicated, and it becomes difficult to maintain quality assurance.

Furthermore, there are also disadvantages such as a shortened lifespan due to overuse of copying machines and the like.

Therefore, the image forming means that is subject to consumption and deterioration, such as an image bearing member, a developing device, a cleaning device, etc., is configured as a process cartridge, and is removably incorporated into the main body of the cartridge device. A method of withdrawing the cartridge and disposing of it on the basis of the amount etc. has been proposed, for example, in Japanese Patent Application Laid-Open No. 58-202459 and Japanese Patent Application Laid-Open No. 59-34548. On the other hand, JP-A-58-72159 discloses a color copying machine having a process cartridge incorporating an image carrier, a charger, a plurality of developing devices, a cleaning device, etc., and the copying machine also includes the process cartridge. It is said that the process cartridge can be replaced with a process cartridge containing only a black and white developer. Regarding the developer used, a two-component developer consisting of a non-magnetic toner and a magnetic carrier is more likely to cause turbidity of the colorant in the toner than a one-component developer containing a magnetic material in the toner. It is excellent in terms of its clear color tone.

[Problem that the invention seeks to solve]

By the way, a color process cartridge that includes multiple developing units has a more complex structure and is more expensive than a monochrome process cartridge that includes only black and white developing units. Disposable process cartridges are expensive and impractical in terms of cost.

Furthermore, in the case of color process cartridges, the amount of toner consumed varies depending on the developing device, so it is difficult to determine which developing device's toner capacity should be used as a reference. If you discard the developing device based on the one that consumed toner first,
This increases the cost and makes it impractical.

[Means to solve the problem]

(Objective of the Invention) An object of the present invention is to make it possible to replace the plurality of developing units incorporated in a color process cartridge individually as toner is consumed, so that the color process cartridge can be manufactured within a practically allowable cost range. It is an object of the present invention to provide a color image forming device that is disposable, economical, and guarantees copy quality.

(Structure of the Invention) The above object is to provide a color image forming apparatus having a process cartridge incorporating at least an image bearing drum and a plurality of developing devices, in which the plurality of developing devices are individually replaced as toner is consumed. This is achieved by a color image forming apparatus that uses

(Specific Structure and Effects of the Invention) The color image forming apparatus of the present invention includes a process cartridge that integrally incorporates an image bearing drum, a group of color developing devices, a cleaning device, a charger, a static eliminator, etc. as necessary. is removably inserted into the main body of the apparatus, and the developer group is replaced individually as toner is consumed to make copies. The developer used in the present invention may be a one-component developer containing a magnetic toner as a main component or a two-component developer containing a non-magnetic toner and a magnetic carrier. However, the two-component developer is preferred in order to enhance the vivid color tone of the colorant contained in the toner. Further, each developing device of the developing device group incorporated in the process cartridge is provided with a toner chamber for replenishing toner, and toner is replenished within the developing device to continue development. However, the replenishment toner in the developing chamber is limited and is consumed in the process of continuing copying, and the Il image is interrupted.

The developing device group in the color cartridge has a small developer capacity due to space constraints, and for example, about 300 to 500 g is accommodated, and the toner chamber only accommodates about 50 to 100 g of toner. Therefore, in a normal T-bi, the toner in the toner chamber is consumed after copying about 1,000 to 3,000 A4 size sheets. Furthermore, the consumption of toner in the toner chamber varies depending on each developing device. For example, for the three colors of yellow (Y), magenta (M), and cyan (C), consumption of toner in the toner chamber varies depending on the type of document, but in general, M toner and C Toner consumption is relatively high. Y) Toner consumption is low.

In the present invention, the presence or absence of toner in the toner chamber is detected by, for example, an optical detection device, a magnetic detection device, or a detection device (LTD) that uses vibration waveforms of an electrostrictive member, and the developing units are individually replaced based on the signal. That's what I do.

The developing devices may be replaced by pulling out the cartridge from the machine and replacing the developing devices individually, or by forming a group of developing devices into a unit, pulling out the unit from the cartridge, and then replacing the developing devices individually. Alternatively, the developing devices may be replaced individually from the cartridges that remain attached to the machine.

The color image forming apparatus of the present invention may be of either an analog type or a digital type, or may be of a transfer type in which a toner image is transferred onto a transfer material each time using a transfer drum, or a color image forming apparatus using a transfer drum may be used. It is also possible to use a method in which toner images of each color are superimposed on an image carrier and then transferred all at once onto a transfer material.

In addition to the three-color full-color cartridge 4 of Y, M, and C, as shown in FIG.
C, black (BK) 4-color full-color cartridge 4a
s Red (R), Blue CB) two-color functional color cartridge 4b, R, BK two-color functional color cartridge 4csB, BK two-color functional color cartridge 4d, R, B, B K
It may be a three-color functional color cartridge 4e or the like. Further, as a spare for the full-color cartridge 4, for example, a cartridge 4f containing only a black developer may be provided. Note that 1 in FIG. 1 is an image carrier drum rotating in the direction of the arrow, 2 is a charger, 3.3a, 3b, 3c,
3d and 3f are each developer group, 6 is Y, 7 is M, and 8 is C1.
9, 9' are BK developing units, 10i1R, 11 are B developing units, 1
2 is a cleaning device, and 13 is a static eliminator.

Further, the color image forming apparatus of the present invention may have a taram shell structure, in which case it has advantages such as easy insertion and removal of the process cartridge from the machine body, easy jam removal, and easy parts replacement. In addition, when using a clamshell structure,
There is also the advantage that there is no need for gaps for parts replacement, making the device more compact.

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the embodiments of the present invention are not limited thereto.

(Embodiment 1) FIG. 2 is a diagram explaining this embodiment, in which lOO represents a color original, 101 represents an original table, 102 represents an optical system for image exposure, and the optical system is a light source 103. Reflection mirror 104
107, a lens 108, a filter group 109 of B, G, and R, and a filter detection device 11.0.

Note that the light source 103' and the reflecting mirrors 104' to 106'
indicates the positions of the optical system light source and reflection mirror after they have been moved. In this case, a process cartridge 1.30 incorporating an image carrier drum +20, a charger 121, a Y developer 125, an M developer 126, a C developer 127, a pre-cleaning static eliminator 128, and a cleaning device 129 is installed in the machine. It is. The process cartridge 130 is slidably suspended by guide rails 138 and 139 of suspension devices 135 and 136 fixed to the upper housing. Reference numeral 140 denotes a transfer drum; 141 fixes the leading edge of the transfer material to the transfer drum 140; a gripper 142 presses the transfer material against the transfer drum by the action of a solenoid 143 and winds it around the transfer drum in cooperation with the action of an adsorption charger 144; 145 is a transfer device, 146 and 147 are static eliminators, and 148 is a transfer material separation claw.

150 and 151 are cleaning devices for the surface of the transfer drum after separating the transfer material, and 152 is the gripper 15.
154 is the separation claw 148;
It is a cam that does the talent of 〉゛・off.

160 is a hollow shaft of the image carrier drum 120 that rotates in the direction of the arrow, and 161 is a toner receiver of the cleaning device 129, which is connected to a pipe 162 containing a coil spring 163 for transporting waste toner. The waste toner thus scraped off by the cleaning device +29 was continuously collected into the image carrier drum 120, and when the process cartridge was replaced, the waste toner was disposed of outside the machine.

Next, the Y developing device 125, the M developing device 126, and the C developing device 1
27 are Y toner chamber 155, M toner chamber 156,
It has C toner chambers 157, each of which contains 70 g of replenishment toner, and is integrated into a unit that can be inserted into and removed from the cartridge 130. Further, remaining toner amount detectors 165, 166, 167 are arranged in the toner chambers 155, 156, 157, respectively, to detect the remaining amount of toner in each toner chamber. copy 200
At the 0th sheet, the signal from the M developer 126 causes the CP
216b in the LED display device 216 via U215
is turned on, and then, at the 2010th sheet, the LED display device 216c is turned on in response to a signal from the C developing device +27, warning that the toner consumption of both developing devices has occurred. Then, when the developer unit 122 was pulled out and the M developer and C'fJl developer were replaced to continue color copying, the toner consumption of the Y developer 125 was displayed on the display device 216a at the 3000th sheet.
was displayed and warned, the unit 122 was pulled out and the Y developing device 125 was replaced. The toner remaining amount detection device is a detection device (LTD) that uses vibration of an electrostrictive member, and its details are disclosed in Japanese Patent Laid-Open No. 55-3 proposed earlier by the present applicant.
It is described in No. 6874. In this way, copies were made by replacing the TA imager, but for example, the carrier,
The life of the cartridge is due to fatigue of the image carrier, cleaning member, etc.

In this embodiment, the lifespan of the cartridge 130 is determined. ; An IC memory that stores the limit number of copies is installed, and the signal from the IC memory is compared with the signal from the counter 211 that counts the number of transfer sheets using the signal obtained from the transfer paper detector 210 via the CPU 215, and the cartridge 1 is
The cartridge was replaced at a usage limit of 30, in this example 50,000 color copies.

Reference numeral 271 denotes a supplying means for the transfer material 170, in which the transfer material 170 fed by the paper feed roll 173 from the A4 horizontal size cassette 172 is transferred to the transfer drum by the paper feed guide 177 via the transport rolls 174, 175 and the timing roll 176. 140. The transfer drum 140
Okay, said gripper 14L presser 142, adsorption electrode 1
The transfer material 170 is wrapped and fixed by the action of the transfer pole 145, and the image bearing drum 120 and the transfer drum 140 are rotated by the action of the transfer pole 145, so that a Y toner image, an M toner image, and a C toner image are sequentially layered and transferred. be done. The transfer material 170 carrying the toner images of each color is connected to the removal electrodes 146 and 14.
7, the transfer material 170 is separated by a separating claw 148, and then transported to a fixing device 181 by a transport bell H, 80.
It was ejected to 3.

Next, the specific structure of the clamshell will be explained. 190 is a locking member between 1 on the lower casing of the aircraft and the upper casing;
300 is a release position regulating member. Hold the handle 185,
With axis P as the rotation axis, 1 is placed on the lower casing while the upper casing is opened. Locking member 1 supported by
Push up the knob 191 of 90 against the spring 192. As a result, the operator 193 rotates clockwise around the shaft 194, pushes down the top end of the interlock 195, and rotates the interlock 195 counterclockwise around the shaft 196 against the spring 197. .

In this way, the lower rear end of the moeki interlocking member 195 is disengaged from the locking tool 198, and the upper housing can be opened upward by the handle, and the spring 201 of the position regulating member 200 is released.
It opens slowly due to the spring pressure.

The position regulating member 200 is a ring body 202, one end of which is rotatably supported by a shaft 2 provided in the lower housing.
and a ring body 204-, one end of which is rotatably supported by a shaft 203 provided in the upper housing, and the ring body 202-
and the other end of the ring body 204 is a shaft 305 that is not supported by the housing.
are coupled together so that they can rotate about a common axis. Further, a spring 206 is provided between the shafts 201 and 203,
The closing and opening of the casing is gently operated by the buffering action based on the spring pressure of the spring 206. When the position regulating member 200 is closed on the housing, the position regulating member 200 is
02 and 204 are folded, but as the upper housing is opened, they stand up against the spring pressure of the spring 206, and when opened (opening angle 20a), both rings extend linearly. At the same time as stopping the opening of 2 on the upper case,
2 is supported on the upper casing.

When the lid is closed, the ring bodies 202 and 204 of the position regulating member 200 are folded through a process reverse to that described above.

On the other hand, when the lid is closed, the locking member 190 is automatically engaged with the locking tool 198 by the action of the spring 207 as the lower end of the interlock is kicked by the shoulder on the upper surface of the locking tool 198 and rotates.

Furthermore, the process cartridge 130 is
The alignment between the transfer drum 140 and the transfer drum 140 was automatically achieved.

The developer used in this example is as follows.

Carrier: A coated carrier was obtained by coating a core material of ferrite particles with an average particle size of 50 μm with styrene acrylic ci:1)ST resin to a thickness of 1 μm.

Toner: Polyester tree Mr UXK-120PJ (
(manufactured by Kako Co., Ltd.) 100 parts by weight Quinoline yellow coloring pigment 1.0 parts by weight Polypropylene "Viscol 660PJ (manufactured by Sanyo Kasei Co., Ltd.) 4-layer i
The average particle size is 11 by mixing, cooling, crushing, and classifying
It was made into a μm toner. A developer of this example was obtained by mixing 7 parts by weight of toner per 1 part of the carrier 100tj.

Using an OPC photoreceptor as an image carrier, 50,000 color copies were continuously made as described above using the color image forming apparatus having the above configuration and replacing each developer. the result,
High quality color images were continuously obtained.

(Embodiment 2) FIG. 3 shows a digital color image forming apparatus for explaining this embodiment. 424, a developer unit 422 integrally incorporating a BK developer 425;
A process cartridge 430 that encloses a charger 421 and a cleaning device 429 is removably incorporated into the machine body. Each of the developing devices includes a toner chamber 426 for replenishing toner,
427 and 428 are provided, and a remaining toner amount detection member LTD436 is provided in each toner chamber.

437 and 438 are installed, and the remaining amount of toner in the toner chamber is detected by the detection member during copying, and the CPU 5
50 through LED 551 (551a, 551b, 5
51c) was lit and a warning was issued, and the corresponding developer was replaced.

The cleaning device 429 also includes a screw conveyor 530 for collecting waste toner into a collection box 531.
are combined.

A color original 300 placed on an original platen 301 is read by the reading system described below, and an image is formed by writing onto an image carrier drum 400 using a laser beam modulated by the obtained reading signal. In the reading system, 310 is a document scanning unit, in which reflected light from a light source 320 is reflected by a reflection mirror 322, and red (R) is reflected by a color separation prism 323.
, cyan (C), and converted into two systems of electrical signals, R and C, by a photoelectric conversion device 324 consisting of a 2fi CCD. These signals were each amplified by an amplifier II 325, converted into digital signals by an A/D converter 1S 326, and outputted to the image processing device 340. In the image processing device 340, the two systems of R and C digital signals are processed in a color separation information generating section and separated into three colors, R, B, and BK, and recording signals of the three colors are obtained. , of which only the R signal was extracted and output to the laser scanner 350.

351 is a polycon mirror, and 352 is an f-θ lens.

In the scanner 350, a laser beam is modulated by an R recording signal, and the R recording signal is written on an image carrier drum 400 made of an OPC photoreceptor that has been uniformly charged by a charger 421, thereby forming an electrostatic latent image. Ta.

This electrostatic latent image was reversely developed in a non-contact manner by the R developing device 423 to form an R toner image on the image carrier.

Next, a cleaning device 429, a transfer 1 separator 500.
501 etc. is released, the image carrier is rotated, and an electrostatic latent image is formed by laser exposure based on the next B recording signal.
A B toner image was formed superimposed on the toner image. Further, in the same manner, laser exposure based on the BK recording signal and development using a BK developer were performed to form a BK l-toner image superimposed on the R toner image and the B toner image. These superimposed toner images are transferred from a cassette 510 to a delivery roll 511, a conveyance roll 512, and a timing roll 5.
The images were transferred all at once onto the horizontally fed A4 size transfer material conveyed by 13 by the transfer pole 500, separated by the separation pole 501, and conveyed to the fixing device 515 by the conveyor bell 1-514.

After being heated and fixed with a heat roll, the paper was discharged onto a paper discharge tray 517 by a discharge roll 516, and a desired full-color image was obtained.

The process cartridge 430 is suspended by cartridge suspension devices f 480 and 481, and the protrusions 485 and 48 are attached to the guides 111483 and 484.
6 was mated and slid to be inserted and removed from the aircraft.

Further, the following developer was used in this example.

Carrier: 1 μm of styrene-acrylic (1:1) #R resin in the core material of copper-zinc ferrite particles with an average particle size of 40 μm.
Coded carrier coated with m thickness.

Toner: Polyester resin r UXK-120PJ (manufactured by Kakosha) + 00! ! Volume: Borizlovirene "Viscol 660PJ (manufactured by Sanyo Chemical Co., Ltd.) 41i: Colored pigment Pigment Red
10 parts by weight or more were mixed in a Henshil mixer, thoroughly mixed with three rolls at 140°C, cooled in air, coarsely pulverized, finely pulverized with a jet mill, and classified to obtain R colored particles with an average particle size of 1111 m. I got it. In addition, colored particles of B and BK were obtained by using phthalocyanpur carbon black instead of pigment red as a coloring agent.

R developer, B developer, and BK developer were obtained by mixing 7 parts by weight of toner per 100 parts by weight of the carrier.
;.

Loading each developer into the color image forming apparatus shown in FIG. 3,
A functional color image was formed by horizontally feeding an A4 size sheet as a transfer paper. In this example, an OPC photoconductor is used.
When copying 000 sheets, a toner consumption signal is output from the LTD438 of the BK developer 425, and the LTD
ED551c has occurred and a warning has been output, so stop copying, pull out the developer unit 422, and close the developer unit 422.
5 exchanges were made. After that, when I continued copying, the result was 300.
At the 0th sheet, a signal is output from the LTD 436 of the R developer 423, and the LED 551a lights up, and then at the 3100th sheet, a signal is output from the LTD 437 of the B developer 424, and the LED 551a lights up.
51b turned on and issued a warning, copying was stopped, the developer unit 422 was pulled out, and the developers 423 and 424 were replaced. After that, I made a large number of color copies in succession while replacing each developing device.

On the other hand, on the w#4 machine 301, there is a functional color image 300 and R, B, BK color patches (
2X 25cm square) 302 is provided to copy the toner image, and the toner image is transferred to the sensor 540 (540R, 540B, 540
BK) is used to detect the density of each color, and the signal is used to detect the density of each color.
It was compared to the reference value from the reference density memory via the PU550.

When the continuous copying reaches 60,000 sheets, the standard density is 0.6.
The cartridge 430 was replaced.

As a result of creating a large number of color copies as described above, stable high image quality was obtained.

An advantage of this embodiment is that since the superimposed toner images of each color are transferred at once, a transfer drum is not required, and the device can be made smaller and lighter.

In addition, since the developing device is replaced as the toner in the developing device is consumed, both the toner and carrier are updated, and stable color copying is maintained at all times.Also, since it is a digital method, it is easy to control the image quality, and the image quality can be easily controlled at all times. It has the advantage of providing high image quality. In this way, a cartridge for color copying was achieved within a practical cost range, and the quality of color copies was guaranteed.

〔Effect of the invention〕

As is clear from the above description, according to the color@image forming apparatus of the present invention, a process cartridge for color image formation is adopted, and a plurality of developing devices in the cartridge can be replaced according to toner consumption. Therefore, effects such as the ability to continuously obtain high-quality color copies within a practical cost range can be achieved.

[Brief explanation of the drawing]

Figure 1 shows examples of various color cartridges; Figure 2 shows examples of various color cartridges;
Figures 1 and 13 are cross-sectional views of a color image forming apparatus for explaining an embodiment. 1.120,400... Image carrier drum 3.3a, 3
b, 3c, 3d, 3e, 3f - developer group 4.4a, 4b
, 4c, 4d, 4e, 4f, 130, 43f)...Process cartridge 6.7, 8, 9, 10, 11, 125, 126, 127
, 423, 424, 425... 2nd development 155.156.157.426, 427.428...
・Toner chamber 165.166.167.436,437,
438...LTD215.550-CPU
216,551--LEDtf [Konica Co., Ltd. Figure 2

Claims (1)

[Claims] A color image forming apparatus having a process cartridge incorporating at least an image bearing drum and a plurality of developing devices, wherein the plurality of developing devices are individually replaceable as toner is consumed. Image forming device.