JP2001228677A - Color image recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized color image recording device having excellent maintenability that a beautiful color image is obtained with a simple constitution. SOLUTION: Relating to this color image recording device, whole plural image forming unit 1Bk, 1Y, 1M and 1C groups containing toner in different color are turnably moved so that each of them can be successively shifted to the same image forming position 50. The image forming unit forms an image by a signal light 13 at the image forming position 50, and the toner image is transferred on an opposed intermediate transfer 32. Moreover, a discharging lamp 7 for discharging a photoreceptor 9 is disposed on an outside of a supporting body and in the vicinity of the photoreceptor 9 on the transfer position downstream side from the photoreceptor 9 to the intermediate transfer belt 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a color printer,
The present invention relates to a color image recording apparatus applicable to a color copying machine, a color facsimile, and the like.

[0002]

2. Description of the Related Art In general, in order to form a color image by electrophotography, a method of forming a color image by superposing toner images of yellow, magenta, cyan, and black on a transfer member has been adopted. In recent years, in order to reduce the size and simplify maintenance of such an apparatus, a plurality of image forming units are held on a rotating support as shown in JP-A-62-287264, and one exposure is performed. There has been proposed a color electrophotographic apparatus for forming a color image on paper wound on a transfer body while exchanging an image forming unit with the means. Hereinafter, an example of such an apparatus will be described with reference to FIG.

[0003] In FIG. 4, reference numeral 101 denotes four image forming units 102a, 10a, 10a of cyan, magenta, yellow, and black.
The rotary frame 2b, 102c, and 102d is rotatably supported by the support shaft 103 and rotates at the timing of development.

[0004] Each unit containing four color toners has the same configuration, and only the toner is different. The structure of the image forming unit and the image forming process of the image forming unit 102a stopped at the image forming position in FIG. 4 will be described in detail.

The image forming unit 102a has a photosensitive drum 108 made of a sensitized organic photoconductor, a primary charger 110, and a cleaner unit 111. On the other hand, a semiconductor laser (not shown) is provided outside the image forming unit 102a, and the signal light output from the laser is axially moved on the photosensitive drum 108 by a polygon 106 rotated at a constant speed by a motor. And exposure scanning. In FIG. 4, 1
Reference numeral 07 denotes a lens system, and reference numeral 104 denotes a mirror for changing the traveling direction of laser light.

[0006] The signal light output from the semiconductor laser according to the image signal of each color exposes the photosensitive drum 108 uniformly charged by the charger 110 to form an electrostatic latent image.
Thereafter, the electrostatic latent image is developed by the developing device 109 to form a toner image on the photosensitive drum 108. On the other hand, the transfer material is fed by a feed roller 114 and is uniformly wound around the surface of the transfer drum 112. The toner image formed on the photosensitive drum 108 is transferred onto a transfer material wound around the transfer drum 112 by a transfer charger 113 provided inside the transfer drum 112.

After the transfer, the toner remaining on the photosensitive drum 108 is collected by a cleaner unit 111. The photosensitive drum 10 whose surface has been cleaned by the cleaner unit 111
Numeral 8 stops the rotation after the charge is removed by the charge removing lamp 105.

After the above-described image forming operation is completed, the rotating frame 101 is rotated by 90 ° and each unit is rotated by 90 ° so that the unit 10 is located at the lowest image forming position.
In place of 2a, the unit 102b moves and stops and is fixed.

Next, an image is created using the unit 102b. For this, the semiconductor laser is modulated according to the image signal corresponding to the color of the toner of the unit 102b, and the unit 1b is modulated.
02b, a latent image is formed and development is performed.
2 is superimposed and transferred on the toner image already transferred on the transfer material wound around 2. The following process is unit 1
02a.

As described above, the image forming process is performed for each of the four units, and four color toner images are superimposed on the transfer material held on the transfer drum 112 to form a color image. The transfer material on which the color image is formed is separated from the transfer drum 112 by the separation claw 115. Thereafter, the transfer material is conveyed on a conveyance belt 116, where the toner image is fixed by a fixing device 117, and then discharged onto a tray 118.

[0011]

When an image is output by the above-described apparatus, a gap between two adjacent image forming units held on a rotating support and constituting a part of an optical path is large. Since various gaps were opened on the side of the image forming unit group attached to the device, the heat lamp of the fuser and other light from the outside entered the optical path as stray light, By lowering the surface potential, light fog of toner was generated on the background of the image. Furthermore, when the static elimination lamp provided in the rotation center area of the image forming unit group is turned on, a part of the static elimination light also becomes stray light and enters the optical path of the signal light to lower the surface potential of the photoconductor. , And thin toner fog was generated.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a small and excellent color image recording capable of outputting a good color image without causing thin toner fog due to stray light when outputting the image. An apparatus is provided.

[0013]

In order to achieve the above object, a color image recording apparatus according to the present invention comprises a plurality of image forming units having a toner storage section, a photoreceptor, and a developing roller, which are formed in a substantially circular and mutually annular manner. A rotatable member which is detachably assembled adjacent to the photoreceptor, an image forming means for forming an image by scanning signal light on the photoreceptor, and an image formed on the photoreceptor to an intermediate transfer unit. In a color image recording apparatus for transferring to a recording sheet via an accommodated intermediate transfer body, the color image recording apparatus is arranged outside the rotary body and in the vicinity of the photosensitive body at a position downstream of a transfer position from the photosensitive body to the intermediate transfer body. And a charge removing means for removing charge on the surface of the photoreceptor.

According to this configuration, the size of each image forming unit can be reduced by providing only one charge removing means for the photosensitive member outside the rotational movement of the unit and on the main body near the image forming position. In the case where the light elimination means such as an LED or a lamp is used as the elimination means, the penetration of the elimination light into the signal light optical path is reduced as compared with the case where the elimination lamp is provided in the unit rotation center area as in the conventional example. The surface potential of the photosensitive member can be kept constant even when the static elimination lamp is lit, and the temperature of the center of rotation of the image forming unit group is not increased by the lamp, and the stability is good. Can output color images.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention comprises an electrostatic image carrier, each rotating at least, and developing means having developers of different colors, respectively, and different colors on the electrostatic image carrier. A plurality of image forming units, a transfer member capable of forming a color image by superimposing a plurality of color toner images formed by the image forming unit, and the electrostatic image at a single transfer position Transfer means for transferring the toner image on the carrier to the transfer body, exposure means for performing image exposure at a single exposure position associated with the transfer position, each of the plurality of image forming units, Moving means for rotating the entire image forming unit group to sequentially position the image forming unit group corresponding to the exposure position and the transfer position; and supporting the plurality of image forming unit groups and rotating by the moving means. And a gap between two adjacent image forming units of the plurality of image forming unit groups forms at least a facing pair of walls surrounding an optical path of the exposure unit, Further, in the state where the image forming unit group is supported by the support, the end faces forming the optical path walls of the two image forming units are planes substantially parallel to each other.

Further, the present invention comprises an electrostatic image carrier each rotating at least and developing means having developers of different colors, respectively, and a toner image of a different color is provided on the electrostatic image carrier. A plurality of image forming units, a transfer body capable of forming a color image by superimposing a plurality of color toner images formed by the image forming unit, and a single transfer position on the electrostatic image carrier. Transfer means for transferring the toner image to the transfer member, an exposure means for performing image exposure at a single exposure position associated with the transfer position, and each of the plurality of image forming units, at the exposure position Moving means for rotating and moving the entire image forming unit group in order to sequentially position the image forming units corresponding to and corresponding to the transfer position; and supporting and rotating the plurality of image forming unit groups by the moving means. And a support, wherein a gap between two adjacent image forming units of the plurality of image forming unit groups forms at least a facing pair of walls surrounding an optical path of the exposure unit, and The gap between the two image forming units is 20 mm or less when the image forming unit group is supported by the support.

Further, the present invention comprises an electrostatic image carrier each rotating at least, and developing means having developers of different colors, respectively, and a toner image of a different color on the electrostatic image carrier. A plurality of image forming units, a transfer body capable of forming a color image by superimposing a plurality of color toner images formed by the image forming unit, and a single transfer position on the electrostatic image carrier. Transfer means for transferring the toner image to the transfer member, an exposure means for performing image exposure at a single exposure position associated with the transfer position, and each of the plurality of image forming units, at the exposure position Moving means for rotating and moving the entire image forming unit group in order to sequentially position the image forming units corresponding to and corresponding to the transfer position; and supporting and rotating the plurality of image forming unit groups by the moving means. And a support, wherein a gap between two adjacent image forming units of the plurality of image forming unit groups forms at least a facing pair of walls surrounding an optical path of the exposure unit, and The color of the end faces of the at least two image forming units that form the optical path wall is black. Further, the present invention includes an electrostatic image carrier each of which rotates at least, and a developing unit having a developer of a different color, so that toner images of different colors can be formed on the electrostatic image carrier. A plurality of image forming units, a transfer body capable of forming a color image by superimposing a plurality of color toner images formed by the image forming unit, and a toner image on the electrostatic image carrier at a single transfer position Transfer means for transferring to the transfer body, and exposure means for performing image exposure at a single exposure position associated with the transfer position,
Moving means for rotating the entire image forming unit group to sequentially position each of the plurality of image forming units at an image forming position corresponding to the exposure position and corresponding to the transfer position; and A support that supports a unit group and is rotated by the moving unit, wherein two adjacent image forming units of the plurality of image forming unit groups are arranged on a wall surrounding an optical path of the exposure unit. An optical path wall is formed in a direction parallel to a scanning plane of the exposure unit, and a support of the image forming unit forms an optical path wall in a direction perpendicular to the scanning plane of the exposure unit.

Further, the present invention comprises an electrostatic image carrier each rotating at least, and developing means having developers of different colors, respectively, wherein toner images of different colors are formed on the electrostatic image carrier. A plurality of image forming units, a transfer body capable of forming a color image by superimposing a plurality of color toner images formed by the image forming unit, and a single transfer position on the electrostatic image carrier. Transfer means for transferring the toner image to the transfer member, an exposure means for performing image exposure at a single exposure position associated with the transfer position, and each of the plurality of image forming units, at the exposure position Moving means for rotating and moving the entire image forming unit group in order to sequentially position the image forming units corresponding to and corresponding to the transfer position; and supporting and rotating the plurality of image forming unit groups by the moving means. It has a support and, in rotational movement outside of the plurality of image forming unit group, and is characterized by providing a discharging means capable of neutralizing the surface charge of the latent electrostatic image bearing member in the vicinity of the image forming position.

In the structure of the present invention, the gap between the adjacent image forming units is constituted by a substantially parallel plane. By adjusting this plane to be substantially parallel to the scanning plane of the signal light, the gap can be formed without obstructing the optical path. It can be narrow and long. Further, when the gap between the adjacent image forming units is large, the amount of stray light entering the optical path of the signal light also increases, and the surface potential of the photosensitive member is significantly reduced due to the stray light, but the width of the gap is set to 20 mm or less. Thus, stray light that enters the optical path of the signal light can be reduced, and a decrease in the surface potential of the photoconductor due to the stray light can be prevented. Further, by making the portion of the image forming unit that forms the optical path wall black, even when stray light enters the optical path, reflected light of the stray light is weakened, and the influence of the stray light on the surface potential of the photosensitive member can be reduced. . Further, in addition to forming the wall surface parallel to the scanning surface of the signal light as a part of the image forming unit, the wall surface perpendicular to the scanning surface (side wall of the optical path of the signal light) is formed of the image forming unit support. By doing so, it is possible to reduce the penetration of stray light from the unit rotation moving side surface in a state where the image forming unit is mounted on the support. Further, each image forming unit can be miniaturized by providing only one charge removing means for the photoconductor outside the rotational movement of the unit and on the main body near the image forming position. In addition, in the case where a light erasing means such as an LED or a lamp is used as the erasing means, penetration of the erasing light into the signal light optical path is reduced as compared with the case where the erasing lamp is provided in the unit rotation center area as in the conventional example. The surface potential of the photoreceptor can be kept constant even when the static elimination lamp is lit, and the temperature of the rotation center region of the image forming unit group is not increased by the lamp, so that it is stable and good. Can output color images. Hereinafter, the configuration of the color image storage device will be described with reference to the drawings using a color electrophotographic apparatus as an example.

FIG. 1 is an overall configuration diagram of a color electrophotographic apparatus according to an embodiment of the present invention. First, four sets of fan-shaped image forming units 1Bk, 1Y, 1M, and 1C for each color of black, yellow, magenta, and cyan form an image forming unit group in the center, and are arranged in an annular shape as shown in the figure. Have been. Each image forming unit is made of the same constituent members except for the developer contained therein, so that the image forming unit for black will be described for simplification of description, and the other colors will be omitted. Note that, for each color, the same portions are denoted by the same reference numerals, and if it is necessary to distinguish each color, a character indicating each color is denoted by the reference numeral. FIG. 2 shows the details of the black image forming unit 1Bk.

In FIG. 2, reference numeral 9 denotes an organic photoreceptor in which phthalocyanine is dispersed in a polycarbonate binder resin;
0 is a charging roller for negatively charging the photoconductor 9, 13 is a signal light by a laser beam, 14a is a first hopper containing a developer obtained by mixing a carrier and toner, 14b
Is a second hopper containing only toner, 15 is an opening opened for toner supply, 16 is a lid for opening and closing the opening 15, and 17 is an agitator for toner supply, 18a and 18b. Reference numeral denotes an agitator for transporting the developer in the first hopper 14a to the developing portion.

Reference numeral 19 denotes a rotatable developing electrode roller made of aluminum; 20, a non-rotating magnet coaxially fixed inside; 20, an AC high-voltage power supply for applying a voltage to the developing electrode roller 19; Is a magnetic blade that regulates the thickness of the toner layer. The diameter of the photoconductor 9 is 30 m
m, the electrode roller 19 was rotated in the direction of the arrow at a peripheral speed of 60 mm / s, and the electrode roller 19 was 16 mm in diameter and rotated in the direction of the arrow at a peripheral speed of 60 mm / s.

In the first hopper 14a, a two-component developer 26Bk obtained by mixing a ferrite carrier having a particle diameter of 50 .mu.m and a toner 25Bk, the surface of which is coated with a silicone resin, was placed and adhered to the surface of the photoreceptor 9 by magnetic force. The toner used is obtained by dispersing a pigment or the like in a polyester resin and further adding an additive.

In the second hopper 14b, 400 g of toner is hermetically stored at the time of assembling the image forming unit, and it is possible to output 5,000 originals equivalent to 5% of A4 single color without replenishing toner from outside the unit. ing.

Reference numeral 27 denotes a cleaner for cleaning the toner remaining on the surface of the photosensitive member 9 after the transfer. The operation of the image forming unit configured as described above will be described below with reference to FIG.

The photosensitive member 9 is charged with a charging roller 10 at -700 V
Was charged. The photosensitive member 9 was irradiated with signal light 13 by a laser beam to form an electrostatic latent image. At this time, the photosensitive member 9
Had an exposure potential of -100V.

The surface of the photosensitive member 9 is coated with a two-component developer 26B.
k was passed in front of the rotating electrode roller 19.
At this time, when the photosensitive member 9 passes through the uncharged region, the AC voltage (frequency: 750 V0-p (peak-to-peak 1.5 kV)) obtained by superimposing a DC voltage of +100 V is applied to the electrode roller 19 by the AC high-voltage power supply 21. (1.8 kHz). Thereafter, when passing through the surface of the photoconductor 9 on which the electrostatic latent image has been written and charged to -700 V, the electrode roller 19 is superposed with a DC voltage of -400 V by the AC high voltage power supply 21 to 750 V0-p (peak-to-peak). An AC voltage (frequency: 1.8 kHz) with a peak of 1.5 kV was applied. Then
A negative-positive inverted toner image was left only on the image area on the photoreceptor 9.

Thus, a black toner image is obtained on the photoreceptor 9. The image forming unit shown in FIG. 2 is an image forming unit for black, and also shows the vertical position of the image forming unit at the image forming position. In the figure, toner 25Bk
Is stored in the first hopper 14a.
Since the cleaner 27 is located on the lower side of the printer, the toner supply and cleaning can be smoothly performed without providing a feed mechanism or a stirring mechanism for moving the developer or the toner inside the toner hopper 14b or the cleaner. It can be performed. That is, in the toner hopper 14b, the toner is supplied to the vicinity of the opening 15 by the rotation of the unit and its own weight,
In the cleaner, the toner scraped by the blade falls to the bottom of the cleaner by its own weight and separates from the photosensitive member 9.

Further, reference numeral 28 denotes a photoreceptor cover for protecting the photoreceptor 9, and FIG. 2 shows a state in which it is opened for image formation. The photoreceptor cover 28 covers the photoreceptor 9 when the image forming unit is located at a position other than the image forming position 50, and prevents contamination of the photoreceptor 9 and in-machine contamination by toner when the image forming unit rotates. It has become.

Image forming units 1Y, 1 other than black
M and 1C have the same configuration and operate.

Referring again to FIG. 1, the configuration of the printer unit will be described. Image forming unit 1B arranged in an annular shape
k, 1Y, 1M and 1C are supported by a support body 6 and are driven by a moving motor 30 as a moving means controlled by a control circuit 29 as a whole, around a cylindrical fixed and non-rotating shaft 31. Can be rotated in the direction of the arrow. Each image forming unit sequentially has an image forming position 5 facing a transfer roller 33 that supports an intermediate transfer belt 32 described later.
It is moved to 0 and positioned. The image forming position 50 is also an exposure position by the signal light 13. Image forming unit 1B
The support 6 of k, 1Y, 1M, and 1C has means (not shown) for detecting that each image forming unit has moved to the image forming position 50, and each time the movement of each image forming unit is completed. A signal corresponding to the completion of the movement is transmitted to the control circuit 29.

Reference numeral 3 denotes a laser exposure device, which is a signal light 13 of a laser beam modulated by a signal input to a printer unit.
Which is generated by the image forming units 1Bk and 1Bk in FIG.
The light enters the mirror 5 fixed inside the shaft 31 through a transparent window 4 opened in a part of the shaft 31 through the optical path formed between the fan-shaped portions of C, and is reflected to the image forming position 50. The photosensitive member 9 of a certain image forming unit is irradiated to form a latent image.
In the state of FIG. 1, it acts on the image forming unit 1Bk for black.

FIG. 3 is an enlarged view of an optical path portion formed by two adjacent image forming units. Here, the optical path up to the mirror 5 is constituted by two parallel flat end faces of two adjacent fan-shaped image forming units. The optical path formed by the end faces of the unit has a width of 10 mm and a length of 70 m.
m, optical path length from outer periphery of unit to mirror is 100m
m. In addition, the unit end surface forming the optical path is formed in the longitudinal direction over the entire area from the near side to the back side of the support 6, and further, at a portion where the image forming unit and the support 6 are in contact with each other, the end face of the support 6 is formed. The gap is made as small as possible to prevent stray light from entering the gap. The side wall of the optical path is formed by the support 6 of the unit to prevent stray light from entering from the side. Further, the color of the exterior of the image forming unit is black, which weakens the reflected light of the stray light entering the optical path on the wall of the optical path, and prevents the stray light from penetrating deeply and lowering the surface potential of the photoconductor 9. In.

In FIG. 1, 7 is an LED (wavelength 660n).
m), which is located at the image forming position 50;
During the image formation, the surface of the photoconductor 9 after the transfer of the toner image is irradiated to remove the surface charge remaining on the photoconductor 9.

Reference numeral 60 denotes a magnetoresistive toner concentration sensor installed on the shaft 31.
First hopper 1 of the image forming unit when positioned at
4a so that the toner density in the area 4a can be detected.

Reference numeral 32 denotes an intermediate transfer belt having a thickness of 100 μm.
It is made of an endless belt-shaped film made of semiconductive urethane as a base material, and is wound around a transfer roller 33 and a stainless roller 34 formed of urethane foam having a low resistance treatment formed around the film, and can be moved in the direction of the arrow. Has become.

The transfer roller 33 is lightly pressed against the photosensitive member 9 of the unit 1Bk at the image forming position 50 via the intermediate transfer belt 32. The roller 34 includes the intermediate transfer belt 3
A second transfer roller 35 having the same configuration as the above-described transfer roller 33 is lightly pressed to be rotatable and driven via the transfer roller 2.

Intermediate transfer belt 32 and second transfer belt 35
A paper transport path is formed in the pressed nip portion so that the paper is sent from the paper supply unit 36.

Reference numeral 40 denotes a belt cleaner section including a belt cleaner for cleaning the intermediate transfer belt 32.

Reference numeral 44 denotes a fixing unit for fixing the toner image on the sheet after the transfer, and reference numeral 45 denotes a discharge roller for discharging the sheet after the fixing.

The above is the description of the main structure of the color electrophotographic apparatus and the image forming unit of the present invention. Next, the operation of this apparatus when forming a color image will be described.

First, each image forming unit 1Bk, 1Bk
Y, 1M, and 1C are located at positions as shown in FIG. 1, the image forming unit 1Bk for black is positioned at the image forming position 50, and a toner density sensor 60 is provided on a side wall of the image forming unit.
Are located so that they almost touch each other. This position 50 is also a position facing the transfer roller 33. The black signal light is input to the image forming unit 1Bk by the laser exposure device 3, the operation of the image forming unit is started, and an image is formed with black toner. Simultaneously with the start of image formation
The toner concentration sensor 60 starts to detect the toner concentration of the developer in the first hopper 14a, and in response to the detection signal, when the toner in the first hopper 14a runs short, the agitator 17 pushes the lid 16 open to open. Supply toner.

The image forming speed of the image forming unit 1Bk (equal to the peripheral speed of the photosensitive member) and the moving speed of the intermediate transfer belt 32 are set to be the same. By the operation, the black toner image is transferred to the intermediate transfer belt 32. Image forming unit group 1
The entirety of Bk, 1Y, and 1C are driven by the moving motor 30 to rotate integrally in the direction of the arrow in FIG.
The image forming unit 1Y stops at the position where the image forming unit 1Y reaches the image forming position 50 by rotation, and the elephant forming unit 1Y is positioned.
Since the portion other than the photoconductor 9 of the image forming unit 1Y is located inside the rotating arc at the tip of the photoconductor 9, the intermediate transfer belt 32 does not contact the image forming unit 1Y.
As before, the laser exposure apparatus inputs signal light to the image forming unit 1Y using the yellow signal, and the yellow toner image is formed and transferred. At this time, the timing of writing the yellow signal light is controlled such that the next yellow toner image is positionally matched with the black toner image previously transferred onto the intermediate transfer belt 32. During this time, the second transfer roller 35 and the cleaner section 40 are slightly separated from the intermediate transfer belt 32, and do not act on the toner image thereon.

The same operation as described above is performed for magenta and cyan, and the four color toner images are superimposed on the intermediate transfer belt 32 in a position-matched manner to form a color image. After the transfer of the final cyan toner image, the four color toner images are collectively transferred to the sheet sent from the sheet feeding unit 36 at the same time by the action of the second transfer roller 35. The toner image transferred to the paper is fixed by the fixing device 44.
Thereafter, the sheet is discharged out of the apparatus via a discharge roller 45. The transfer residual toner remaining on the intermediate transfer belt 32 is cleaned by the action of the cleaner unit 40 to prepare for the next image formation.

Next, the operation in the single color mode will be described. In the monochrome mode, first, an image forming unit of a predetermined color is moved to the image forming position 50 and positioned. Next, image formation of a predetermined color and transfer to the intermediate transfer belt 32 are performed in the same manner as before. This time, the transfer is continued as it is after the transfer, and the sheet fed from the sheet feeding unit 36 by the next second transfer roller 35 Transfer to

The above is the description of the configuration and operation of the embodiment. According to the present invention, since the image formation of each color is performed at the same image forming position without using a transfer drum having a complicated structure, accurate color registration can be performed with a simple structure, and The forming units are completed independently as one image forming unit for each color, and have excellent maintenance characteristics such as simple configuration and easy replacement of each color. Become.

Further, in the present configuration, the optical path of the signal light composed of two adjacent image forming units can be narrowed, and the device can be made small, and stray light hardly enters the optical path. Further, by setting the color of the exterior of the image forming unit to black in which light is hardly reflected, the influence of stray light on the image can be reduced.

In this configuration, since each of the image forming units 1Bk, 1Y, 1M and 1C including the photoreceptor 9 can be independently adjusted externally, for example, an image forming unit that has already been adjusted at the time of shipment from the factory can be used on site. It can be easily replaced by adjustment.

Since the photosensitive member 9 is covered except during image formation, the photosensitive member 9 is not damaged or stained, and the inside of the apparatus is not stained by scattering of the developer.

Further, in this configuration, since the size of the intermediate transfer member can be reduced, the size of the apparatus can be reduced, and furthermore, the registration position of each color toner image on the intermediate transfer member can be easily and accurately adjusted.

In this embodiment, a color image is formed by superimposing toner images of each color on the intermediate transfer belt 32 as an intermediate transfer member. However, a drum is used as an intermediate transfer member, and a toner image of each color is superimposed thereon. In a configuration in which a color image is formed, a transfer material such as paper is held on an intermediate transfer body such as a drum and a belt, and the toner images of the respective colors are sequentially transferred and superimposed directly on the transfer material to form a color image. Does not change the essence and the function and effect of the present invention.

In the above embodiment, a two-component developing method in which a carrier and a toner are mixed is used as a developing method for an image forming unit. However, even in the case of a one-component developing method using only a toner, the present invention can be applied. The essence and effect do not change.

[0053]

As described above, the present invention does not use a transfer drum having a complicated structure, has a simple structure, and forms images of all colors at the same image forming position.
Accurate color registration can be performed with a simple configuration. By making the optical path of the signal light composed of two adjacent image forming units parallel and narrow, and by making the color of the exterior of the part constituting the optical path black, there is no effect on the image due to stray light, which is favorable. Color images can be obtained. By providing only one discharging lamp for the photoconductor near the image forming position, the size of the image forming unit can be reduced, and the influence of the discharging lamp on the image can be reduced.

[Brief description of the drawings]

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

FIG. 2 is a configuration diagram of an image forming unit used in the color electrophotographic apparatus according to the embodiment of the present invention.

FIG. 3 is a configuration diagram of an optical path of signal light configured by an image forming unit of the color electrophotographic apparatus according to the embodiment of the present invention.

FIG. 4 is a configuration diagram of a conventional color electrophotographic apparatus.

[Explanation of symbols]

 1Bk, 1C, 1M, 1Y Image forming unit 3 Laser exposure device 5 Mirror 6 Support 9 Photoconductor 13 Signal light 28 Photoconductor cover 32 Intermediate transfer belt 33 Transfer roller 35 Second transfer roller 50 Image forming position 60 Toner density sensor

Claims (1)

[Claims] A rotating body having a plurality of image forming units each having a toner storage section, a photoconductor, and a developing roller, which are collectively arranged in a substantially annular shape and adjacent to each other so as to be detachable; An image forming unit that scans a signal light to form an image; and a color image recording apparatus that transfers an image formed on the photoreceptor to recording paper via an intermediate transfer body accommodated in an intermediate transfer unit. Outside the rotating body, and disposed near the photoconductor downstream of the transfer position from the photoconductor to the intermediate transfer body,
A color image recording apparatus comprising a charge removing means for removing charge on the surface of the photoreceptor.