JPH02188772A - Color image forming device - Google Patents

Abstract

PURPOSE:To obtain a color copy without color slurring which has high image quality by constituting an image forming process cartridge and a transfer process cartridge so that they can be freely inserted in and drawn from a device main body, mutually opposing the arrangement of the respective process cartridges with respect to the device main body and making it in a lateral direction. CONSTITUTION:An image carrier drum 111, a developing device group for color 115-117, a cleaning device 121, an electrostatic charger 112, a destaticizer 121 or the like are integrally contained in the image forming process cartridge 110. A transfer drum 151, a paper supplying cassette 160, a fixing unit 171, a means for supplying and ejecting paper to them or the like are integrally contained in the transfer process cartridge 150. Then, an image exposure device, the image forming process cartridge 110, the transfer process cartridge 150 or the like are set so that they can be inserted in and drawn from the device main body and arranged in the lateral direction. Thus, the positions of the image carrier drum 111 and the transfer drum 151 are easily decided. Simultaneously, positional deviation during copying operation is prevented from occurring and the copy having the high image quality is stably obtained.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention is a compact type having an image forming process cartridge and a transfer process cartridge that can be inserted into and removed from an apparatus main body and are disposable depending on the usage limit. The present invention relates to a color image forming apparatus.

[Conventional technology]

There have been very few conventional monochrome or color copying machines in which the image carrier drum and the transfer drum are disposed horizontally to each other, except in special cases, and these machines have not been put to practical use.

As the special case, for example, Japanese Patent Application Laid-Open No. 58-585
Japanese Patent No. 58 discloses a color image forming apparatus in which an ion flow control screen drum, an image carrier drum, a transfer drum, and a paper conveying means are arranged horizontally with respect to the main body of the apparatus. In this case, it is considered that the horizontal arrangement was adopted because it was necessary to incorporate the three drums into the main body of the apparatus without difficulty, and because of the process of forming an image using an ion flow control screen. However, the horizontal position arrangement has the following advantages, and is particularly advantageous in color image forming apparatuses.

(1) Since the transfer drums can be arranged horizontally, a plurality of developing devices can be arranged with sufficient margin.

(2) The paper conveying means can be arranged with sufficient margin, for example, the paper can be conveyed horizontally.

(3) It becomes easy to set the position of the transfer drum, and the set position is less likely to fluctuate during copying operations.

(4) The optical system is disposed on the image forming section with sufficient space.

On the other hand, in the field of copying machines and the like, a technique has been proposed in which an image forming device is integrated into a cartridge.

For example, JP-A No. 58-202459 and JP-A No. 5
In order to ensure the quality of copied images in a black-and-white copying machine, Japanese Patent No. 9-34548 proposes a technique in which an image forming device is made into a cartridge and the cartridge is made disposable depending on the usage limit. There is also an example of applying this technology to a color copying machine, for example, in Japanese Patent Application Laid-Open No. 58-72159
A color process cartridge has been proposed that includes an image carrier drum, a charger, a plurality of color developing devices, a cleaning device, etc., and is configured to be freely inserted into and removed from an apparatus main body.

[Problem to be solved by the invention]

However, in the color image forming apparatus described in Japanese Unexamined Patent Publication No. 58-72159, since the process cartridge is disposed above the transfer drum, it is difficult to set the position of the image carrier drum with respect to the transfer drum. The setting position is likely to fluctuate during insertion/removal or copying operations, resulting in poor transfer and color shift in the copied image. In addition, since the developing section is large, the conveyance path for the transfer paper becomes narrow, which tends to cause poor conveyance of the transfer paper.Also, since the developing section and the paper conveyance path are close to each other, toner tends to adhere to the transfer paper, and the copied image may become contaminated.

In addition, the space in which the exposure system is installed becomes too small, which tends to result in an unreasonable configuration. In particular, in the case of a digital system, the exposure system is composed of a reading system and a writing system with complicated circuit configurations, which tends to result in an unreasonable design.

[Means to solve the problem]

(Object of the Invention) The object of the present invention is to develop a color image forming device into a cartridge, a paper transport mechanism including a transfer drum into a cartridge, and a stable arrangement of an exposure system, an image forming device, and a paper transport transfer mechanism. , thereby making it easier to replace parts of the device, clearing jams, etc., and more stably ensuring the quality of color copies.

(Structure of the Invention) A color image forming apparatus having a plurality of developing devices, a transfer drum, and a paper conveyance means on the outer periphery of an image bearing drum, an image forming process cartridge including the image bearing drum and a plurality of developing devices; A color image, characterized in that a transfer drum and a transfer process cartridge including a paper conveyance means are configured to be freely inserted into and removed from an apparatus main body, and each of the process cartridges is arranged in a horizontal position with respect to the apparatus main body so as to face each other. Forming device.

(Specific structure of the invention and its operation) The color image forming apparatus of the present invention is an apparatus that performs image formation using a transfer method each time using a transfer drum, and the entire apparatus includes an image exposure system, an image forming equipment system, It is divided into three systems: the paper conveyance system including the transfer drum, and among these, the image forming system and the paper conveyance system including the transfer drum are each made into a cartridge, which can be inserted into and removed from the main body of the apparatus and placed in a horizontal position. It is said that

Incidentally, the cartridges are tentatively named an image forming process cartridge and a transfer process cartridge, but it is preferable that both of them be able to be inserted into and removed from the apparatus main body in the lateral direction. In this way, in the color image forming apparatus of the present invention, the image exposure device, the image forming process cartridge, the transfer process cartridge, etc. are arranged in a stable horizontal position, and the positioning of the image bearing drum and the transfer drum is easy, and it is possible to easily align the image bearing drum and the transfer drum during the copying operation. High-quality copies can be stably obtained without causing any misalignment.

The image forming process cartridge of the present invention integrally includes an image bearing drum, a group of color developing devices, a rinsing device, a charger, a static eliminator, etc., and the transfer process cartridge includes a transfer drum, a supply A paper cassette, a fixing device, a means for supplying and discharging paper therefor, and the like are integrally included.

The image forming process cartridge is replaced according to the lifespan of the cartridge, but it is expensive because it includes a group of color developing units, and it is usually replaced based on the lifespan of the image carrier. is preferred. Therefore, during that time, it is necessary to replenish toner to the developing device and continue copying.

Therefore, each developing device may be provided with a toner chamber for replenishing toner, and when the toner in the toner chamber is consumed, the cartridge may be pulled out and the developing device replaced. Alternatively, the developing devices may be integrated into a unit. Alternatively, the cartridge may be replaced and the cartridge reinstalled to continue copying.

Alternatively, toner may be replenished by inserting and removing a cylinder for toner replenishment into each developing device. In addition, to dispose of the waste toner collected in the cleaning device, the waste toner is conveyed to the hollow rotating shaft of the image carrier drum using a spring coil, and the waste toner of the image carrying drum is conveyed through a toner drop hole provided in the hollow rotating shaft. The waste toner may be collected within the drum or by inserting and removing a toner collecting cylinder into the cleaning device. Copying continues by replenishing the toner, replacing the developing device, collecting waste toner, etc., but the cartridge is replaced when the image bearing drum reaches the end of its lifespan, which is approximately 50,000 to 80,000 copies.

On the other hand, the transfer process cartridge is inserted into and removed from the machine body when replacing parts due to deterioration of equipment such as the transfer drum and fixing device, or when dealing with jams.

The image forming process cartridge and the transfer process cartridge are installed in a horizontal position with respect to the main body of the apparatus so that the image bearing drum and the transfer drum included in each cartridge are disposed facing each other. It is preferable that the image forming process cartridge and the transfer process cartridge are installed by sliding horizontally from the side of the apparatus main body. However, in some cases, the apparatus main body has a thalamusiel structure in which the upper housing containing the exposure system can be opened relative to the lower housing, and when the upper housing is opened, the cartridge is vertically dropped into the lower housing and installed. You can do it like this.

Next, as an image forming process cartridge to be incorporated into the color image forming apparatus of the present invention, as shown in FIG.
In addition to the three-color full-color cartridge 4 of Y (yellow), 2M (magenta), and C (cyan), for example, Y, M, and C
, BK (black) may be used. Furthermore, for example, two of red (R) and blue (B)
Color functional color cartridge 4b, R, B
K two-color functional color cartridge 4c1
It may also be a cartridge 48 for functional colors of two colors, B and BK, and a cartridge 48 for functional colors of three colors, R, B, and BK. Further, as a spare for the full color or functional color cartridge, a cartridge 4f or 4g for only a black and white developer may be provided.

In FIG. 1, 1 is an image carrier drum that rotates in the direction of the arrow, 2 is a charger, and 3.3 a, 3 b, and 3 c.

3d, 3e, 3f, 3g are each developer group, 5 is a Y developer,
6 is an M developer, 7 is a C developer, 8.8', 8'' is a BK developer, 5a to 10a are toner supply chambers built into each of the above-mentioned developers, and 8b is a multi-toner for BK) toner. 11 is a cleaning device, 12 is a cleaning blade, 13 is a pre-cleaning static eliminator, and 14 is a pre-transfer charger.

Next, the color image forming apparatus of the present invention may be an analog type apparatus with a simple image exposure system, or may be a digital type apparatus that allows easy image quality conversion and adjustment and image editing. .

〔Example〕

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) FIGS. 2A and 2B are a cross-sectional view and a side view of an analog color image forming apparatus for explaining this embodiment. In the figure, 100 is a color original, 101 is an original platen, 102
represents an optical system for image exposure, and this optical system includes a light source 103
, reflective mirrors 104 and 105, lens 106, B
, G, R, and Nd switching filters 107. The main body of the apparatus includes an image carrier drum ill.

A developing unit 1-114 consisting of a charger 112, a Y developer 115, an M developer 116, and a C developer 117, a pre-transfer charger 118, and a pre-cleaning static eliminator 121. An imaging process cartridge 110 having a cleaning device 121 including a cleaning blade 122 is incorporated. The Y developer 115 is provided with a Y toner chamber 115a and a Y toner remaining amount detector 115b, and the M developer 115 is provided with a Y toner chamber 115a and a Y toner remaining amount detector 115b.
16 is provided with an M toner chamber 116a and an M toner remaining amount detector 116b, and the C developing device 117 is provided with an M toner chamber 116a and an M toner remaining amount detector 116b.
17a and a C toner remaining amount detector 117b are provided.

The process cartridge 110 is inserted from the right side of the drawing in a horizontal position using a handle 125, and is inserted into the bottom plate 126 of the main body of the apparatus.
and abutting members 130 and 13 extending from the top plate 128
It is mounted in contact with one side of 1. Note that 127 is a guide rail provided on the bottom plate 126, and the cartridge 110 is mounted by sliding on the guide rail 127. After the cartridge is installed, the locking member 1
32, it is firmly set in the main body of the device. Locking member 1
32 has a support member 133 fixed to the device main body, a shaft 134 passing through the support member 133, and a locking metal fitting 136 that rotates integrally with the support member 133.
6 is rotated downward in the drawing, the action of the spring 135 pushes the cartridge 110 to the left in the drawing.

Next, the transfer process cartridge 150 integrally includes a transfer drum 151, a paper feed cassette 160, a fixing device 171, and a transfer paper conveyance means.

The transfer process cartridge 150 is inserted in a horizontal position from the left side of the drawing by a handle 165, and the abutment members 130 and 1 are inserted in the same manner as in the case of the image forming process cartridge.
It is mounted in contact with the other surface of 31.

After the cartridge 150 is installed in the apparatus main body, it is firmly set in the apparatus main body by the locking member 166 in the same manner as described above.

Note that the paper discharge tray 172 is attached after the cartridge 150 is attached to the main body of the apparatus, and is removed before the cartridge is pulled out. Further, it is preferable that the paper feed cassette is also inserted and removed in the same manner as the paper discharge tray 172. In this example, a color image was formed using the color image forming apparatus shown in FIG. 2 in the following manner. As the original platen 101 moves in the direction a, the original 100 is irradiated with light by the light source 103, and the reflection mirror 104, lens 106, reflection mirror 105, and B, G are irradiated with light.

An image carrier il consisting of a positively charged OPC photoreceptor rotates in the direction of the arrow through an R, Nd color separation filter 107.
Colored electrostatic latent images were formed on the 1. First, in the first rotation of the image bearing drum 111, the color separation filter 107
The B filter is selected as a filter, and the document scanning light is image-exposed on the image carrier through the B filter to form an electrostatic latent image, and a two-component negative toner is developed by the Y developer 115 of the developer unit 110. Regularly developed by contact method with agent
A toner image was formed. This Y toner image was transferred onto an A4-sized horizontally fed transfer sheet that was conveyed from the paper feed cassette 160 to the transfer drum 151 via the L roll 1611 and the timing roll 162. Here, the leading edge of the transfer paper supplied to the transfer drum 151 is fixed to the transfer drum 151 by the gripper 151, and the transfer paper is fixed to the transfer drum 151 by the gripper 151.
The transfer paper is wound up sequentially as the transfer paper 51 rotates, but due to the cooperative action of the pusher 152, which has the function of pressing the transfer paper against the transfer drum by the action of a solenoid, and the adsorption electrode 157, the transfer paper is evenly and tightly rolled onto the transfer drum. wrapped around me
.

Next, in the next rotation of the image bearing drum Ill, the G filter is selected as the color separation filter 107 and imagewise exposed, and the obtained electrostatic latent image is developed by the M developer 116 to form an M toner image. Ta.

This M toner image was superimposed and transferred onto the Y toner image on the transfer paper conveyed by the rotation of the transfer drum. Further, in the same manner, the R filter is selected and exposed, and developed by the C developing device 117 to form a C toner image, which is then deposited on the Y toner image and M toner image on the transfer paper conveyed by the rotation of the transfer drum. They are transferred in layers, and Y,
Three color toner images of M and C were formed. The transfer paper carrying the three-color toner image was neutralized by a static eliminator 154, separated by a separator 156, conveyed to a fixing device 171 by a conveyor belt 170, and discharged to a paper discharge tray 172 after fixing.

In addition, in the cleaning device 121, each time a toner image of each color is transferred, residual toner on the image carrier Ill after transfer is neutralized by a static eliminator 121 and scraped off by a blade 122, and the scraped waste toner is sent to a waste toner supplement. It is collected in the collection cylinder 123,
When replacing the developing unit (14), which will be described later, it is pulled out and disposed of outside the apparatus, and replaced with a new cylinder.

In addition, each developer in the developer unit l14 has 100
gram of replenishment toner was sealed in each toner chamber, but at the 4000th color copy, the remaining toner amount detector 116b of the M developing device 116 issued a warning that the toner was consumed. At this point, copying is stopped, the cartridge 110 is pulled out, the developer unit 114 is replaced, and the cartridge 110 is replaced again.
10 and continued copying.

- An operation panel 140 shown in FIG. 3 is provided on the upper part of the main body of the blade device, and a large number of keys are arranged to display various usage limit numbers of copies of the image forming cartridge. In this embodiment, r7. Qx 100OOJ key is pressed, 700
It was specified that 00 copies were the maximum number of copies. Further, a counter 142 receives a signal from a detection device 141 provided in the process of transporting the transfer paper, and counts the number of copies.
The signal is sent to the old CP 43 and the panel 14
It was compared with the specified usage limit number starting from 0. Copying continues by repeating the replacement of the developer unit, and when the counter reaches the specified number of copies, 70,000, copying is stopped.

In this example, although the process cartridge 11O was inserted and removed every time the developing unit was replaced, there was no problem in positioning it with the transfer drum, and a high-resolution color image without color turbidity was obtained from beginning to end. Furthermore, although a transfer paper jam occurred twice during the copying operation, the jam was easily cleared by inserting and removing the transfer paper processing unit 150, and there was no kinks in alignment with the image forming process cartridge 110, and the transfer The wrapping and fixing of the transfer paper on the drum 151 was accurate, and there were very few troubles in conveying the paper.

In this embodiment, instead of the full-color image forming process cartridge 110, a cartridge exclusively for black-and-white copying as shown in FIG. It is also possible to make an I copy every revolution of the drum. In that case as well, the use limit number of copies exclusively for black-and-white copying is designated on the panel 140.

(Embodiment 2) FIG. 2 is a sectional view of a digital color image forming apparatus for explaining this embodiment. In the figure, 200 is a functional color original, 201 is an original platen, the original is read by the following reading system, and a semiconductor laser beam modulated by the obtained reading signal is applied to an image carrier drum in an image forming process cartridge (described later). 300 and image formation was performed. In the reading system, 210 is a document scanning unit, in which the reflected light from a light source 220 is reflected by a reflection mirror 222, and a color separation prism 223 separates red (R), red (R),
The color was separated into cyan (C) and converted into two systems of electrical signals, R and C, by a photoelectric conversion device 224 consisting of two CCDs. These signals were each amplified by an amplifier 225, converted into a digital signal by an A/D converter 226, and outputted to the image processing device 240. In the image processing device 240, the two systems of R and C digital signals are processed in a color separation information generating section and separated into three colors of R, B, and BK to obtain recording signals of the three colors. The recording signals were output to a laser scanner 250 for each color, and were sequentially written on an image carrier drum 300 made of a negatively charged OPC photoreceptor by modulating a semiconductor laser beam. Note that 251 is a polygon mirror, and 252 is an f-θ lens.

In the color image forming apparatus of this embodiment, unlike the analog system of the first embodiment, the image forming process was a digital system. That is, in Example 1, image exposure using color-separated light of B, G, and R, regular contact-type development using each developing device for Y, M, and C, and transfer onto a transfer paper for each development are performed, and the image is transferred onto the transfer paper after each development. Three-color toner images of Y, M, and C were formed and fixed to form a full-color image, but in this example, toner images of R, B,
Writing with a laser beam modulated by a BK digital recording signal, non-contact reversal development using each developing device for R, B, and BK, and transfer onto a transfer paper for each development are performed, and R, B, A three-color toner image of B and K is formed and fixed to form a functional color image.

However, the device configuration and functions of the image forming section other than the reading and writing systems are completely the same as in Embodiment I, and the image forming process cartridge and the transfer process cartridge are
Both screws were placed horizontally on the main body of the device and could be inserted and removed from the side. Although detailed explanation is omitted, the names of each part are as follows.

310 is an image forming process cartridge, and the cartridge 310 includes chargers 311. A developer unit 314 that integrates an R developer 315, a B developer 316, and a BK developer 317, an image carrier drum 300, and a pre-transfer charger 31
8. A cleaning device 321 having a static eliminator 321, a blade 322, and a waste toner collection cylinder 323 is incorporated.

In addition, approximately 100 pieces of R toner for replenishment are stored in the R developing device 315.
A toner chamber 315a that encloses the toner g and a remaining amount detector 315b that detects the remaining amount of toner in the toner chamber are built-in.

Similarly, the B developing device and the BK developing device are also connected to the B toner chamber 31.
It has a 6a% B toner remaining amount detector 316b, a BK toner chamber 317a, and a B K toner remaining amount detector 317b.

Next, 350 is a transfer process cartridge, and this cartridge 350 includes a gripper 3511 and a transfer paper presser 35.
2. Transfer drum 3511 having transfer pole 353, static eliminator 354, separation claw 356, adsorption electrode 357, etc. Paper feed cassette 3601 Supply roller 1611 Timing roller 362
, a paper conveying means including a transfer paper conveying belt 370 after separation, and a fixing device 371 are incorporated. Note that the paper feed cassette 360 and the paper discharge tray 372 can be inserted into and removed from the transfer process cartridge 350, and when the cartridge 350 is inserted and removed, the cartridge 350 is operated with the cassette removed.

Furthermore, the handles 325 and 365 are used when the image forming process cartridge 310 and the transfer process cartridge 350 are inserted and removed, and the locking members 332 and 366 are used after the image forming process cartridge 310 and the transfer process cartridge 350 are installed in the apparatus main body. This is to securely lock the

In this embodiment, a functional color original 200 is placed on the original table 201, and the original scanning units 210 to 2
Scanning exposure is performed while running at 10', color separation prism 223 separates this into R and C, photoelectric conversion is performed at 244, amplification is performed at 225, A/D conversion is performed at 226, and output to image processing device 240. The three-color recording signals of R, B, and BK were color-separated. During the first rotation of the image forming drum 300, the R recording signal is taken out, the laser beam of the laser scanner 250 is modulated, the R recording signal is written on the image bearing drum 300, and the R developing device 315 conducts non-contact reversal development to form an R) toner image. was formed and transferred onto A4 size horizontally fed transfer paper P fed via the transfer drum 351.

Thereafter, two of the image bearing drum 300 and the transfer drum 351
In the rotation and the third rotation, writing based on the B recording signal, development/transfer by the B developing device 316, writing based on the BK recording signal, and writing based on the BK recording signal in the same manner as described above.
7 is developed and transferred, and R, B, B are printed on the transfer paper.
The toner images of each color of K are transferred onto the transfer drum 35 in an overlapping manner.
1, are separated and conveyed by a separator 356, and fixed.
, BK functional color copies were obtained.

While copying continued, at 4,000 copies, a toner consumption warning was issued from the toner remaining amount detector 316b of the B developer 316, so the copying was stopped, the cartridge 310 was pulled out, the developer unit 314 was replaced, and the copying was continued.

On the other hand, the key r7.5x 100OOJ on the panel 340 in FIG. 3 provided on the top surface of the apparatus was pressed, and the maximum number of copies of 75,000 copies for the image forming process cartridge 310 was designated. A counter 342 that counts the number of copies based on the signal from the transfer paper detection sensor 341 during copying.
A signal from the panel 34 is output to the CPU 343 and
The number of copies is compared with the copy limit signal from 0, and the number of copies is 7 while copying is continuing due to repeated replacement of the developer unit.
Copying stopped when it reached 5000 sheets. During this period, color copies continued to have high image quality from start to finish, and several paper feed jams that occurred during copying were eliminated very easily by inserting and removing the transfer process cartridge 350. In addition, there was no difficulty in positioning due to insertion and removal of the image forming process cartridge 310 and the transfer process cartridge 350, and no color shift occurred in the color image.

〔Effect of the invention〕

As is clear from the above description, according to the color image forming apparatus of the present invention, the apparatus is divided into three parts: an image exposure system, an image forming process cartridge, and a transfer process cartridge. It was considered easy to replace. In addition, since each of the cartridges is arranged horizontally and inserted and removed horizontally from the side of the apparatus using a butting method, the alignment between the image bearing drum and the transfer drum is always maintained accurately.151, 351...Transfer There were no problems with positioning during the copying operation, and high-quality color copies with no color shift were always obtained.

[Brief explanation of the drawing]

Claims (1)

[Claims] In a color image forming apparatus having a plurality of developing devices, a transfer drum, and a paper conveying means on the outer periphery of an image bearing drum, an image forming process cartridge including the image bearing drum and a plurality of developing devices, and the transfer drum and paper conveying means. 1. A color image forming apparatus, characterized in that a transfer process cartridge including means is configured to be freely inserted into and removed from an apparatus main body, and each of the process cartridges is arranged in a lateral position with respect to the apparatus main body so as to face each other.