JP2001215772A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive image forming device which can be attached to an optional position without restricting the attaching positions of respective color developing devices and can form on image high in quality. SOLUTION: Plural developing devices 10A, 10B, 10C and 10D storing different color developer, respectively, develop an electrostatic latent image formed on the surface of a photoreceptor 1 so as to form a toner image for discriminating developer color of every color on the surface of the photoreceptor 1. The device is provided with a developer color detecting means 12 near the surface of the photoreceptor 1, and the means 12 detects the color of the toner image for discriminating the developer color of every color formed on the surface of the photoreceptor 1. A developer color information storage means 18 stores the detected color information, and an image printing condition control means 14 controls the image printing condition of the toner image for an image based on previously decided image printing order information and the stored color information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a printer, a facsimile, and a copying machine, and more particularly to an electronic apparatus for developing and visualizing an electrostatic latent image formed on a photosensitive member or an insulator by a developing device. The present invention relates to an image forming apparatus using a photographic method.

[0002]

2. Description of the Related Art In general, an electrophotographic recording apparatus for forming an electrostatic latent image on a photoreceptor or an insulator, developing and visualizing the electrostatic latent image with a developing device using a developing device, and forming an image has a plurality of colors. Multicolor image recording is performed by overlapping. Generally, it is known that full-color image recording can be performed by superimposing three primary colors of cyan, magenta, and yellow in multicolor image recording.

Many current color image recording apparatuses perform full-color image recording by superimposing four color images obtained by adding black to these three primary colors. Black can be expressed by superimposing all three primary colors, but it is frequently used because it records characters and is generally added because it is an important color in image quality.

In such an image forming apparatus using a multi-color developer, the developing device is formed in a cartridge shape detachable from the image forming device for each color. A developing cartridge that allows a user to replace the developing cartridge and facilitates maintenance has been put to practical use.

The mounting position of the developing cartridge in the image forming apparatus is predetermined for each color, and when printing image data of each color, the printing is performed by the developing cartridge at the mounting position corresponding to each color. It is controlled to be performed. Therefore, unless the developing devices for the respective colors are mounted at the correct positions, the correct colors cannot be recorded in the final recorded image.

For example, when a cyan developing cartridge is mounted in a place where a magenta developing cartridge should be mounted, cyan is printed in magenta image data. Therefore, when mounting the developing cartridge to the image forming apparatus, it is necessary for the user to confirm and mount the developing cartridge at a predetermined position.

However, since many developing cartridges have the same appearance for each color, when a user mounts the developing cartridge on the image forming apparatus, the user tends to mistake the mounting position. Therefore, means for preventing such erroneous mounting is required.

[0008] As a general means to prevent erroneous mounting,
Changing the color of the cartridge, engraving on the surface of the cartridge, pasting a seal stating the prescribed items,
In some cases, a user is allowed to identify the type of the developing device, thereby preventing erroneous mounting.

Further, a key having a different shape for each color is mounted on the surface of the cartridge so that the key can be mechanically mounted only at a predetermined position.

The image forming apparatus described in Japanese Patent Application Laid-Open No. 7-152307 is provided with an identification means for electrically identifying a developing cartridge, and a warning is displayed when the cartridge is erroneously mounted by detecting the identification means. Have been.

In the image forming apparatus described in Japanese Patent Application Laid-Open No. H11-161113, the developing cartridge has storage means for storing development color information of a developer contained in the cartridge. There is disclosed a configuration in which developer information is read, a match / mismatch with regular color information is determined, and if there is a mismatch, an image forming operation is prohibited.

[0012]

Of the above-mentioned prior arts, the method of changing the appearance of the developing cartridge every time the color or type of the developer is different is to change the type of the developing device each time the color of the developer is different. The cost of mass production increases.

In a method of mounting a key having a different shape for each color on the surface of the cartridge, the shape of the developing unit housing can be made the same for each color, which does not lead to a large increase in cost, but the user is forced to notice the wrong mounting. Attempts to insert the cartridge into the image forming apparatus may damage the cartridge and the image forming apparatus.

In the method described in Japanese Patent Application Laid-Open No. 7-152307, an erroneous insertion warning is issued only after the cartridge is inserted into the image forming apparatus. For this reason, the user who has issued the warning must re-install the correct developing cartridge, which places a burden on the user and is inefficient.

Similarly, in the system described in Japanese Patent Application Laid-Open No. 11-161113, a warning of erroneous insertion is issued after the cartridge is inserted into the image forming apparatus main body, and the image forming operation is prohibited. The user must reinsert the cartridge into the correct cartridge insertion position.

Further, Japanese Patent Application Laid-Open No. 7-152307 and JP-A-11-16111
In each of the methods described in Japanese Patent Publication No. 3 (1993), it is necessary to attach storage means for developing colors and the like to the developing cartridge, which leads to an increase in the cost of the cartridge.

An object of the present invention is to provide an inexpensive image forming apparatus which can be mounted at an arbitrary position without restricting the mounting position of each color developing device, and which has high image quality.

[0018]

In order to achieve the above object, the image forming apparatus of the present invention is characterized in that a plurality of developing devices each containing a developer of a different color are used, and the surface of the photoreceptor is formed. A developer color detecting means for detecting the color of the formed developer color discriminating toner image for each color is provided near the photoconductor surface.

Specifically, the present invention provides the following devices. According to the present invention, a photoreceptor and a developer of different colors are stored, and an electrostatic latent image formed on the surface of the photoreceptor is developed using the respective developers, and a toner image of each color is formed on the photoreceptor surface. In the image forming apparatus having a plurality of developing devices to form a developer color detecting means for detecting the color of the developer color discriminating toner image for each color formed on the photoconductor surface,
An image forming apparatus provided near the surface of the photoconductor is provided.

The present invention also provides a photosensitive member and a developer of a different color, respectively, and develops an electrostatic latent image formed on the surface of the photosensitive member using each of the developers to form a latent image on the surface of the photosensitive member. In an image forming apparatus having a plurality of developing devices for forming a toner image for each color and an intermediate transfer member onto which the formed toner image for each color is transferred, development for each color transferred to the intermediate transfer member is performed. There is provided an image forming apparatus comprising: a developer color detecting unit for detecting a color of a toner color discriminating toner image near a surface of the intermediate transfer body.

Preferably, developer color information storage means for storing color information of the detected toner color discriminating toner image,
A printing condition control unit that controls printing conditions of the image toner image based on the stored color information and predetermined printing order information.

Preferably, the developer color detecting means is an optical reflection type sensor.

Further, according to the present invention, a photoreceptor and a developer of a different color are respectively stored, and an electrostatic latent image formed on the surface of the photoreceptor is developed using each of the developers to form on the surface of the photoreceptor. In an image forming apparatus having a plurality of developing devices for forming a toner image for each color, a color of a developer color discriminating toner image provided for each color formed on the photoconductor surface is provided near the photoconductor surface. Developer color detecting means for detecting, developer color information storing means for storing the detected color information, and printing of an image toner image based on predetermined printing order information and the stored color information. An image forming apparatus comprising: a printing condition control unit that controls a condition.

Further, according to the present invention, a photoreceptor and a developer of a different color are respectively stored, and an electrostatic latent image formed on the surface of the photoreceptor is developed using each of the developers to form on the surface of the photoreceptor. In an image forming apparatus having a plurality of developing devices for forming toner images of respective colors and an intermediate transfer member to which the formed toner images of respective colors are transferred, the image forming device is provided near the surface of the intermediate transfer member, Developer color detecting means for detecting the color of the developer color discriminating toner image for each color transferred to the surface of the transfer member; developer color information storing means for storing the detected color information; An image forming apparatus comprising: a printing condition control unit configured to control a printing condition of an image toner image based on the printing order information and the stored color information.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows the configuration of an image forming apparatus according to an embodiment of the present invention. In this image forming apparatus, a belt-shaped photoconductor 1 serving as an electrostatic latent image carrier is vertically long, and one side (left side in the figure) of the belt-shaped photoconductor 1 is separated from the belt-shaped photoconductor 1 The transfer drum is an intermediate transfer member
2. A transfer device 5 and a fixing device 4 are arranged, and developing devices 10A, 10B, 10C, and 10D filled with toners of four different colors are arranged on the other side surface (right side in the figure).

The colors of the toner contained in the developing devices 10A, 10B, 10C, and 10D are preferably four colors obtained by adding black to the three primary colors cyan, magenta, and yellow. Black can be expressed by overlapping all three primary colors,
It is frequently used because it records characters, and is generally added because it is an important color in image quality.

The developing devices 10A, 10B, 10C, and 10D are configured to be detachable from the color image recording device, and are used for a long period of time. The door 11 on the front of the image forming apparatus can be opened, and a new developing device can be inserted and replaced.

In the conventional image forming apparatus, the place where the developing device is inserted is predetermined for each color, and it is impossible to mechanically insert the developing device at a position other than the determined position. Is controlled so as to prohibit printing.

However, in the image forming apparatus of the present invention, since the place where the developing device is inserted is not limited by the color, the user can insert the developing device of each color at an arbitrary position.

Below the developing device 10D, a belt-shaped photosensitive member 1 is provided.
An exposure device 9 for forming a latent image is disposed in the image forming apparatus, and a paper feed cassette 8 for storing a recording medium is disposed therebelow.

Around the transfer drum 2, a transfer device 5, a charge removing / separating device 32, and a drum cleaner 3 are arranged. Around the belt-shaped photoconductor 1, a charging device 7, a photoconductor cleaner 6, and a surface of the belt-shaped photoconductor 1 And a developer color detecting means 12 for detecting the color of the developed toner image. The belt-shaped photoconductor 1 stretched in the vertical direction is driven in the direction of arrow Q by a driving device (not shown).

First, the toner color discrimination process according to the present invention will be described with reference to FIGS. FIG.
FIG. 2 is an enlarged schematic view of the periphery of a printing unit of the image forming apparatus of FIG. 1.

The toner color discriminating process is performed when the user turns on the power of the image forming apparatus, or closes the door 11 of the image forming apparatus to be opened / closed when replacing the developing apparatus after the power is turned on. A predetermined discrimination pattern is developed in a predetermined order. In the present embodiment, the developing devices 10A → 10B → 10C → 10D
Are performed in this order, but this order is not particularly limited.

First, the photosensitive layer on the surface of the belt-shaped photosensitive member 1 driven by a driving device (not shown) is uniformly charged by the charging device 7. Next, the exposure device 9 performs exposure of a predetermined determination pattern. In this embodiment, the shape of the discrimination pattern is rectangular as shown in FIG. 3, but the shape of the discrimination pattern is not particularly limited as long as the area can be detected by the developer color detection unit 12.

It is preferable that the discriminating pattern exposure position is exposed at a position corresponding to the position of the developer color detecting means 12 installed near the surface of the belt-shaped photosensitive member 1.

Thereafter, the electrostatic latent image of the discrimination pattern formed on the belt-shaped photoconductor 1 is developed by the developing device 10A, and a discrimination toner image 31 is formed on the belt-shaped photoconductor 1. The discriminating toner image 31 developed by the developing device 10A and formed on the belt-shaped photoconductor 1 is provided by a developer color detection unit 12 provided at a position where the developer color on the belt-shaped photoconductor 1 can be detected. Move to the position.

The developer color detecting means 12 is provided with a discriminating toner image 31 formed on the belt-shaped photosensitive member 1 by the developing device 10A.
And the color of the toner contained in the developing device 10A is determined. In the present embodiment, the developer color detecting means
12 uses an optical reflection type sensor.

The light emitted from the light emitting element of the reflection type sensor is reflected on the discrimination toner image 31 and returns to the light receiving element of the reflection type sensor again, and the color of the discrimination toner image 31 can be detected based on the signal. . The toner color information 30 included in the developing device 10A detected by the developer color detecting unit 12
Is sent to the developer color storage means 18 and stored therein.

The toner image 31 for discrimination on the belt-shaped photoreceptor 1 after the color has been discriminated by the developer color detecting means 12 is
The image is transferred to the surface of the transfer drum 2 and then cleaned by the drum cleaner 3.

In the same process, the color of the toner contained in each developing device is sequentially detected and determined in the order of 10B → 10C → 10D, and stored in the developer color storage means 18. That is, at the stage when all the processes are completed, the developer color storage unit 18
The state in which the developing device of which color is mounted at which position is stored. In this embodiment, the developing device 10A is black, 10B
It is assumed that the user has worn yellow, 10C has magenta, and 10D has cyan.

In the electrophotographic system in which four color images are superimposed using the transfer drum 2 as in this embodiment, the order of the colors superimposed on the transfer drum 2 is determined by the color of the final image after being fixed on the paper. Affect. For example, when a red image is obtained by superimposing yellow and magenta, when a magenta image is superimposed on a yellow image and when a yellow image is superimposed on a magenta image, the hue of the final image after fixing is different. Some differences occur. Therefore, the order in which the toners of the respective colors are superimposed, that is, the order in which development or transfer is performed, must always be performed in a fixed color order.

In the present embodiment, this printing is performed in the order of yellow → magenta → cyan → black, but this order is not particularly limited. Printing condition control means
The order of printing in advance at the factory is RO
M, based on the color information of all the developing devices stored in the developer color storing means 18 and the predetermined printing process sequence information, changes the order of the normal printing process to the developing device 10B → Set 10C → 10D → 10A and shift to the printing standby state.

According to the above-described configuration, there is no restriction on the place where each color developing device is mounted, and the developing device does not require a notation member or a detected member. it can.

Next, a normal printing process of the image forming apparatus of the present invention will be described with reference to FIG.

First, the photosensitive layer on the surface of the belt-shaped photosensitive member 1 driven by a driving device (not shown) is uniformly charged by the charging device 7. Next, a personal computer,
The image and the character information are exposed in dot units by an image scanner or the like, and an electrostatic latent image is formed on the belt-shaped photoconductor 1. Thereafter, the electrostatic latent image on the belt-shaped photoconductor 1 is developed by the developing device 10B to be visualized as a toner image.

The belt-shaped photosensitive member 1 is given a certain potential by a power source (not shown), and the transfer drum 2 is connected to the ground. For this reason, the transfer of the toner image from the belt-shaped photoconductor 1 to the transfer drum 2 is performed by these potential differences.

After the image transfer, the belt-shaped photoreceptor 1 is cleaned by the photoreceptor cleaner 6 to remove the residual toner remaining on the belt-shaped photoreceptor 1 that has not been transferred in the first transfer, so that the next toner image can be formed. State.

The above-described one-cycle operation is performed by a transfer drum.
Each color developing device 10C, 10D, 1
0A, a multi-color toner image is formed on the transfer drum 2 by superimposing a single-color toner image.

On the other hand, a recording medium such as a sheet or an OHP sheet is supplied to the transfer device 5 in a timely manner, and a single-color or plural-color toner image formed on the transfer drum 2 is recorded by the operation of the transfer device 5. Is transferred to

After the transfer of the toner image to the recording medium, the recording medium is peeled off from the transfer drum 2 by the charge removing peeling device 32.
The toner is fused and fixed by the fixing device 4, and is discharged onto the upper surface of the main body.

On the other hand, after the transfer to the recording medium is completed, the remaining toner remaining on the transfer drum 2 without being transferred is transferred to the drum cleaner 3.
, And the next toner image can be superimposed.

Further, the image forming apparatus shown in FIG. 1 simplifies the conveyance path from the supply of the recording medium to the discharge of the recording medium as much as possible, and prevents the recording medium picked from the paper supply cassette 8 from being creased. By increasing the radius of curvature, paper jams during conveyance can be prevented, and reliability can be improved. Further, the processing at the time of paper jam can be easily performed. Further, it can correspond to various types of recording media such as cardboard.

In the present embodiment, the recording medium transport path is arranged in a substantially arc shape, and the transfer drum 2, the belt-shaped photosensitive member 1, the developing devices 10A, 10B, 10C, 10D, the exposure device 9 and the like are transported. By arranging it inside the path, the space is effectively used, the body is reduced in size, the transport path is simplified, and when the recording medium is ejected,
The print surface is discharged downward.

By arranging as described above, the transport path can be simplified, and since most of the units are located inside the main body relative to the transport path, the transport path is closer to the machine frame (outer frame). Since the transport path is easily opened, the processing at the time of paper jam can be easily performed. In addition, discharging the printing surface downward at the time of discharging has an advantage that the printing surface is discharged in a printing order from the printing surface side.

Further, by forming the photoconductor in a belt-like configuration, the developing devices 10A, 10B, 10C, and 10D of a plurality of colors can be arranged in the same shape on the same plane of the belt-shaped photoconductor 1, and Since there is no need to change the developing devices 10A, 10B, 10C, and 10D according to the colors to be developed and to change the developing device shape for each color, it is possible to reduce the size and cost.

Further, by arranging the belt-shaped photosensitive member 1 vertically long, the space occupied by the photosensitive member having the same circumference can be reduced, so that the main body can be downsized and the belt-shaped photosensitive member 1 can be reduced in size. When the photoconductor 1 is replaced, it can be pulled out and replaced as it is, thereby improving maintainability.

When the recording medium is conveyed from the lower part of the main body to the upper part, the transfer drum 2 rotates in the direction of arrow U,
By rotating the belt-shaped photoreceptor 1 in the direction of the arrow Q, each contact operates in the forward direction at each contact point, so that a configuration with good development efficiency and less problems such as vibration can be obtained.

Further, the transfer drum 2 can be driven by the belt-shaped photoreceptor 1 so that a configuration with less color shift can be achieved.

FIG. 5 shows the configuration of an image forming apparatus according to another embodiment of the present invention. The difference between the present image forming apparatus and the image forming apparatus of FIG. 1 is that the developer color detecting means 12 is provided near the surface of the transfer drum 2. Each developing device 1
0A, 10B, 10C and 10D detect the color of the toner contained in
The determination is performed using the discrimination toner image transferred to the intermediate transfer drum 2. Other processes are the same as those of the embodiment described with reference to FIG. 1, and the effects are the same.

In the above embodiment, an example relating to a multicolor image recording apparatus mainly using an electrophotographic process has been described. However, in addition to a multicolor image recording apparatus using an electrophotographic process, a monochromatic ink jet array or the like may be used. Can be applied to a multicolor image forming apparatus that forms a color image by superposing images formed by ink jet heads of respective colors on a sheet or an intermediate image forming body.

[0062]

According to the present invention, since the mounting position of each color developing device is not limited and can be mounted at an arbitrary position, the burden on the user at the time of mounting can be reduced.

Further, even if the user attaches each color developing device to an arbitrary position, development and transfer can always be performed in a fixed color order, so that a stable hue image can be obtained in the final image after fixing. Can be.

Further, it is only necessary to provide one detecting means for detecting the developer color, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is an enlarged view around a printing section of the image forming apparatus of FIG. 1;

FIG. 3 is a diagram illustrating an example of a pattern printed for toner color detection in the image forming apparatus of FIG. 1;

FIG. 4 is a diagram for explaining a normal printing process of the image forming apparatus of FIG. 1;

FIG. 5 is a configuration diagram of an image forming apparatus according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Belt-like photoreceptor, 2 ... Transfer drum, 3 ... Drum cleaner, 4 ... Fixing device, 5 ... Transfer device, 6 ... Photoconductor cleaner, 7 ... Charging device, 8 ... Paper cassette, 9 ... Exposure device,
10 developing device, 11 door, 12 developer color detecting means,
13: development characteristic notation means, 14: printing condition control means, 1
5: developing device mounting position, 16: developing roll, 18: developer color storage means, 30: toner color information, 31: toner image for determination, 32: static elimination device

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 21/00 370 G03G 21/00 370 (72) Inventor Masahiko Saito 1-1-1, Higashitaga-cho, Hitachi City, Ibaraki Prefecture No. 1 F-term in the Office Information Equipment Division of Hitachi, Ltd. (Reference) 2H027 DA50 DD05 DE02 EA20 EB04 EC03 EC06 EC20 ED08 ED24 EE07 EF06 EF09 2H030 AA06 AD12 AD16 BB23 BB33 BB42 2H032 AA05 BA01 BA10 DA47 DA63 DB14 DB15 EA24 GA13

Claims (6)

[Claims] An image forming apparatus comprising: a photosensitive member and a developer of a different color stored therein; an electrostatic latent image formed on the surface of the photosensitive member being developed using the developer; and a toner for each color on the surface of the photosensitive member. An image forming apparatus having a plurality of developing devices for forming an image, wherein a developer color detecting unit for detecting a color of a developer color discriminating toner image for each color formed on the surface of the photoreceptor; An image forming apparatus provided in the vicinity. 2. A photoreceptor and a developer of a different color are stored, respectively, and an electrostatic latent image formed on the surface of the photoreceptor is developed using the respective developers, and a toner of each color is formed on the surface of the photoreceptor. An image forming apparatus comprising: a plurality of developing devices for forming images; and an intermediate transfer member onto which the formed toner image of each color is transferred, wherein a developer color discrimination for each color transferred to the intermediate transfer member is provided. An image forming apparatus, comprising: a developer color detecting unit that detects a color of a toner image near the surface of the intermediate transfer body. 3. A developer color information storage means according to claim 1, wherein said detected color information of said developer color discriminating toner image is stored, and said stored color information and a predetermined print are stored. An image forming apparatus comprising: printing condition control means for controlling printing conditions of an image toner image based on order information. 4. An image forming apparatus according to claim 1, wherein said developer color detecting means is an optical reflection type sensor. 5. A photoreceptor and a developer of a different color are stored, respectively, and an electrostatic latent image formed on the surface of the photoreceptor is developed using the respective developers, and a toner of each color is formed on the surface of the photoreceptor. An image forming apparatus having a plurality of developing devices for forming an image, wherein a developer is provided near the surface of the photoconductor and detects a color of a developer color discriminating toner image for each color formed on the surface of the photoconductor. A color detection unit, a developer color information storage unit that stores the detected color information, and controls a printing condition of an image toner image based on predetermined printing order information and the stored color information. An image forming apparatus comprising: a printing condition control unit. 6. A photosensitive member and a developer of a different color are stored, respectively, and an electrostatic latent image formed on the surface of the photosensitive member is developed using each of the developers, and a toner of each color is formed on the surface of the photosensitive member. In an image forming apparatus having a plurality of developing devices for forming an image and an intermediate transfer member onto which the formed toner image of each color is transferred, the image forming device is provided near the surface of the intermediate transfer member, and provided on the surface of the intermediate transfer member. Developer color detecting means for detecting the color of the transferred developer color discriminating toner image for each color; developer color information storing means for storing the detected color information; and predetermined printing order information. An image forming apparatus comprising: a printing condition control unit configured to control a printing condition of an image toner image based on the stored color information.