JP2001296713A - Color image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color image forming device realizing miniaturization and high image quality by arranging a destaticizing means for destaticizing a photoreceptor with destaticizing light on the downstream side from the photoreceptor of each image forming unit in a transfer paper carrying direction and enhancing light utilization efficiency. SOLUTION: In this color image forming device 1, the photoreceptors 31Y to 31Bk of the respective image forming units 30Y, 30M, 30C and 30Bk are destaticized by reflecting the destaticizing light emitted from destaticizing parts 34Y to 34Bk disposed on the more downstream side than the photoreceptors 31Y to 31Bk in the transfer paper 11 carrying direction by transfer paper 11 and the inclined surface 35Yb to 35Bkb of cleaning cases 35Ya to 35Bka and irradiating the photoreceptors 31Y to 31Bk with the destaticizing light. Therefore, the photoreceptor drums 31Y to 31Bk are efficiently irradiated with the destaticizing light emitted from the destaticizing parts 34Y to 34Bk, so that they are destaticized, and the device 1 is miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color image forming apparatus, and more particularly, to a small-sized color image forming apparatus having good image quality.

[0002]

2. Description of the Related Art Recently, demands for full-color image formation have been increasing, and at the same time, there has been a strong demand for high-speed image formation. As a color image forming apparatus that meets such demands, there is a so-called tandem type color image forming apparatus in which a plurality of electrophotographic writing units and image forming units are juxtaposed to form a color image by superimposing images. A device is used.
This tandem type color image forming apparatus has high productivity because each color image is formed independently compared to a color image forming apparatus which sequentially forms and transfers each color image with a single photoconductor. Is the feature.

On the other hand, in recent years, there has been an increasing demand for miniaturization of various devices, and there is also a demand for miniaturization of color image forming apparatuses for forming full-color images.

Therefore, conventionally, a latent image holding member, electrostatic latent image forming means for forming an electrostatic latent image on the surface of the latent image holding member, and a developing device for forming a toner image by attaching toner to the electrostatic latent image surface Means, and a plurality of image forming units having a transfer means for transferring the toner image to a transfer material are continuously arranged, and the toner image formed for each of the image forming units is transferred onto a transfer material surface to be conveyed. And a substantially transparent endless film formed of a dielectric or a resistor having a resistance value of 10 ⁹ Ω · cm or more, and a transfer electric field. A color image forming apparatus has been proposed, wherein a light-emitting body for erasing the charge on the surface of the electrostatic holding member after transfer is provided inside the endless film. That (see Japanese Patent Laid-Open No. 5-53450).

That is, in this color image forming apparatus, the transfer means is constituted by an endless film made of a dielectric or a resistor having a high resistance value and an electric field means for forming a transfer electric field. A luminous body for erasing the charge on the surface of the holding member is provided, and a cleaning unit for cleaning the electrostatic holding member is omitted, thereby achieving miniaturization.

Further, the applicant of the present invention discloses a transfer belt made of a dielectric material which moves in contact with a plurality of photoreceptors in a sequential manner and which is conveyed by the transfer belt. In a transfer apparatus of an image recording apparatus that performs image recording by successively superimposing and transferring images on paper, a conductive member is disposed in proximity to the back surface of the transfer belt from immediately after the most upstream transfer position to a transfer end position. A transfer device is proposed, in which a conductive member is disposed between photoconductors at a predetermined distance from the surface of the transfer belt on the transfer paper transport side of the transfer belt, and is patented. (Patent No. 28
No. 31682).

That is, in this transfer device, in addition to the electric field stabilizing plate on the back side of the transfer belt, a conductive member is further disposed between the photosensitive members on the front side of the transfer belt, and the transfer belt and the back side of the transfer belt are provided. Even if a discharge or disturbance of the electric field occurs between the electric field stabilizing plate and the electric field stabilizing plate on the side, the conductive member disposed opposite to the toner on the transfer paper conveyed to the transfer belt causes a vertical An electric field is generated to stabilize the electric field, prevent image disturbance, and improve image quality.

[0008]

However, in the color image forming apparatus described in the above-mentioned publication, improvements in improving the size of the color image forming apparatus at a low cost and with good image quality are still required. Needed.

That is, if it is attempted to reduce the size of a tandem type color image forming apparatus, the tandem type color image forming apparatus requires at least four image forming units. By doing so, the size of the entire apparatus has been reduced conventionally. When the size of the photoconductor is reduced, it is necessary to similarly reduce the size of the image forming unit disposed around the photoconductor. However, in practice, it is difficult to reduce the size similarly. For example, with respect to a shaft object such as a roller, if the shaft diameter is reduced, bending occurs in the axial direction, and it is difficult to reduce the diameter to a certain value or less. Similarly, miniaturization of other components of the image forming unit is naturally limited.

In the color image forming apparatus, it is required to reduce the size and cost. However, the cost of the color image forming apparatus can be reduced only by reducing the cost of the apparatus body (reducing the initial cost). Rather, it is necessary to reduce the cost of replacement units and consumables generated by using the apparatus (reducing the running cost).

In the color image forming apparatus described in JP-A-5-53450, the transfer means is constituted by an endless film made of a dielectric or a resistor having a high resistance value and an electric field means for forming a transfer electric field. In addition, a luminous body for erasing charges on the surface of the electrostatic holding body after transfer is provided inside the endless film, and a cleaning unit for cleaning the electrostatic holding body is omitted, thereby achieving miniaturization.

However, the transfer unit is generally treated as a replacement unit because its component life is shorter than the life of the main body of the color image forming apparatus. Since the luminous body for erasing the electric charges, that is, the static elimination lamp is provided in the transfer belt which is an endless film, there is a problem that the running cost is high. In addition, since the static elimination lamp is not generally handled as a replacement part, there is a problem in that if it is replaced together with the transfer unit, wasteful costs are incurred and running costs are further increased.

[0013] The applicant of the present invention is disclosed in Japanese Patent No. 283168.
In the transfer device proposed in Japanese Patent Publication No. 2 (1999), an electric field stabilizing plate and a conductive member are interposed between a transfer belt to stabilize the electric field and prevent image disturbance. Is desirably conductive between the conductive members,
A good way to do this is to drop it to ground. The publication discloses that the conductive member is a cleaning unit and at least the bottom of the housing is formed of a conductive material.

However, since the cleaning unit of the color image forming apparatus is usually formed by resin molding, a separate member is provided as a conductive member, or
Although the housing is formed of a conductive resin, the cost may be high. Further, usually, an image forming unit having a cleaning unit or the like often performs attachment / detachment work from the main body, including replacement work based on life.
In this operation, the conductive member provided on the bottom surface of the cleaning unit may be touched and become dirty, and since the conductive member is provided on the bottom surface of the cleaning unit, dirt is hardly found, and an appropriate cleaning operation is not performed. There was a fear.

According to the first aspect of the present invention, there is provided an image forming unit case which has a photosensitive member for forming a toner image of each color of a color image in a main body housing and which is held in a guide rail. A plurality of image forming units are arranged along a conveyor belt that conveys the transfer paper, and static elimination means that emits static elimination light downstream of the photosensitive member of each image forming unit in the direction of conveyance of the transfer paper by the conveyor belt is provided. When each of the photosensitive members on the upstream side in the transport direction of the transfer paper is neutralized with the neutralizing light emitted from each of the neutralizing means,
By subjecting at least a portion of the image forming unit case irradiated with static elimination light emitted from each static elimination unit to a reflection function process of reflecting the static elimination light to the photosensitive member on the upstream side in the transfer paper transport direction of each static elimination unit. By using the static elimination light from the static elimination means arranged downstream of each image forming unit in the direction of transfer of the transfer paper for static elimination of the photoconductor using the image forming unit case, the degree of freedom of the layout of the image forming unit is improved. It is an object of the present invention to provide a color image forming apparatus capable of improving the image quality while reducing the size of the image forming unit as well as reducing the size of the entire apparatus.

According to a second aspect of the present invention, there is provided a color image forming apparatus comprising: a plurality of image forming units disposed along a transport belt; An electric field stabilizer is disposed on the opposite side of the electric field stabilizer, an insulating member is disposed on the side of the conveyance belt of the electric field stabilizer, and at least a portion of the guide rail holding each image forming unit case facing the conveyance belt has a predetermined shape. The electric field stabilizer is formed of a conductive member and functions as an electric field stabilizer. An insulating member is provided on a surface of the electric field stabilizer on the side of the conveyor belt. By applying an anti-reflection function process to prevent the reflection of the neutralization light emitted from the surface, the electric field acting on the transfer paper is stabilized, and the insulating member for stabilizing the electric field reflects the neutralization light, and each neutralization is performed. A color image forming apparatus capable of preventing static elimination light emitted from a stage from being incident on a photoreceptor other than a photoreceptor to be neutralized by the static elimination means, and further improving image quality while reducing the size of the entire apparatus. It is intended to provide.

According to a third aspect of the present invention, the static elimination means is disposed so as to enter an opening formed in the guide rail.
In the color image forming apparatus, the static elimination light from the static elimination unit is
By having a light-shielding mechanism for preventing each static elimination means from entering the photosensitive member on the downstream side in the transport direction of the transfer paper by passing between the guide rail and the image forming unit case, the static elimination means is provided in the guide rail. To further improve the degree of freedom of the layout of the image forming unit, and removes the charge to be removed by the charge removing unit by passing the charge removing light emitted from the charge removing unit between the guide rail and the image forming unit case. It is an object of the present invention to provide a color image forming apparatus capable of preventing light from being incident on a photoreceptor other than the body and further improving the image quality while further reducing the size of the entire apparatus.

According to a fourth aspect of the present invention, the light-shielding mechanism is configured such that at least a portion of the guide rail on the downstream side in the transport direction of the transfer paper from the static elimination means attached to the guide rail protrudes toward the image forming unit case. With the protruding structure that prevents the passage of the light, the static elimination light emitted from the static elimination means can pass between the guide rail and the imaging unit case without changing the shape of the guide rail without using any special member. Provided is a color image forming apparatus capable of preventing the light from passing through to a photoreceptor other than the photoreceptor to be neutralized by the static elimination means and further improving the image quality at a lower cost while further miniaturizing the entire apparatus. It is intended to be.

[0019]

According to a first aspect of the present invention, there is provided a color image forming apparatus, wherein a photoreceptor for forming a toner image of each color of a color image is formed in a main body housing, and is held in a guide rail. A plurality of image forming units respectively housed in the formed image forming unit case are arranged along a conveying belt that conveys the transfer paper, and the transfer paper is conveyed by the conveying belt rather than the photoconductor of each image forming unit. In the color image forming apparatus, a static elimination unit that emits static elimination light is disposed downstream in the direction, and the static elimination light emitted from each static elimination unit neutralizes each of the photoconductors on the upstream side in the transport direction of the transfer paper. In the image forming unit case, at least a portion irradiated with the static elimination light emitted from each of the static elimination units is configured to transfer the static elimination light upstream of each of the static elimination units in the transfer paper transport direction. Wherein by reflection function processing to reflect the photoreceptor is applied, it has achieved the above objects of.

According to the above configuration, a plurality of photoconductors, each of which forms a toner image of a separated color of a color image, are housed in the main body housing, and each of the plurality of photoconductors is housed in an imaging unit case held in a guide rail. The image forming units are arranged along a transport belt that transports the transfer paper, and static elimination means that emits static elimination light downstream of the photosensitive member of each of the image forming units in the direction of transport of the transfer paper by the transport belt are provided. ,
When neutralizing each photosensitive member on the upstream side in the transport direction of the transfer paper with the neutralizing light emitted from each of the neutralizing means, at least a portion of the image forming unit case to which the neutralizing light emitted from each neutralizing means is irradiated, Since the reflection processing is performed to reflect the static elimination light to the photosensitive member on the upstream side of the transfer paper transport direction of each static elimination means, the charge from the static elimination means arranged downstream of each image forming unit in the transport direction of the transfer paper is applied. The static elimination light can be used for static elimination of the photoreceptor by using the imaging unit case, so that the degree of freedom of the layout of the imaging unit can be improved, and the image forming unit can be downsized to make the entire apparatus compact. While improving the image quality.

In this case, for example, as described in claim 2, the color image forming apparatus is provided between the photosensitive members of the plurality of image forming units disposed along the transport belt. An electric field stabilizer is disposed on the opposite side of the image forming unit with the conveyance belt therebetween, and an insulating member is disposed on the conveyance belt side of the electric field stabilizer, and holds each of the image forming unit cases. At least a portion of the guide rail facing the transport belt is formed of a predetermined conductive member to function as an electric field stabilizer, and an insulating member is disposed on a surface of the electric field stabilizer plate on the transport belt side. At least the surface of each of the insulating members on the side of the conveyor belt may be subjected to an anti-reflection function process for preventing reflection of static elimination light emitted from the static elimination means.

According to the above configuration, the color image forming apparatus is arranged between the photosensitive members of the plurality of image forming units disposed along the transport belt and opposite to the image forming unit with the transport belt therebetween. An electric field stabilizer is disposed on the side of the electric field stabilizer, an insulating member is disposed on the side of the electric belt which is on the conveyor belt, and at least a portion of the guide rail holding each image forming unit case facing the conveyor belt has a predetermined conductivity. It is formed of a member and functions as an electric field stabilizing plate. An insulating member is provided on a surface of the electric field stabilizing plate on the side of the conveyor belt. Since the anti-reflection function processing for preventing the reflection of the neutralized light is performed, the electric field acting on the transfer paper can be stabilized, and the insulating member for stabilizing the electric field reflects the neutralizing light. The static elimination light emitted from each static elimination unit can be prevented from being incident on a photoreceptor other than the photoreceptor to be neutralized by the static elimination unit, and the image quality can be further improved while miniaturizing the entire apparatus. it can.

Further, for example, as set forth in claim 3, the charge removing means is disposed so as to enter an opening formed in the guide rail, and the color image forming apparatus is provided with the charge removing means. Has a light blocking mechanism for preventing the charge removing light from passing through the guide rail and the image forming unit case and entering the photosensitive member on the downstream side in the transfer paper transport direction of each of the charge removing means. It may be something.

According to the above arrangement, the static elimination means is disposed so as to enter the opening formed in the guide rail, and the color image forming apparatus is arranged such that the static elimination light from the static elimination means forms an image with the guide rail. A light-shielding mechanism is provided to prevent the charge removing means from entering the photosensitive member on the downstream side in the transport direction of the transfer paper of each of the charge removing units. The degree of freedom of the layout of the image unit can be further improved, and static elimination light emitted from the static elimination means passes between the guide rail and the image forming unit case, except for the photosensitive member other than the photosensitive member to be neutralized by the static elimination means. It is possible to prevent the light from being incident on the photoreceptor, and it is possible to further improve the image quality while further reducing the size of the entire apparatus.

Further, for example, as described in claim 4, the light shielding mechanism is configured such that at least a part of the guide rail on the downstream side in the transport direction of the transfer paper from the static elimination means attached to the guide rail has A projecting structure that projects in the direction of the image forming unit case and blocks the passage of the charge removing light may be used.

According to the above configuration, at least a portion of the guide rail on the downstream side in the transporting direction of the transfer sheet from the static elimination means attached to the guide rail projects in the direction of the image forming unit case to pass the static elimination light. Since the protruding structure is used to block the light, the static elimination light emitted from the static elimination means passes between the guide rail and the image forming unit case without changing the shape of the guide rail without using a special member or the like. It is possible to prevent the static elimination means from being incident on a photoreceptor other than the photoreceptor to be neutralized, thereby further improving the image quality at a lower price while further miniaturizing the entire apparatus.

[0027]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIG. 1 is a view showing a first embodiment of the color image forming apparatus of the present invention. FIG. 1 is a diagram showing a color image to which the first embodiment of the color image forming apparatus of the present invention is applied. FIG. 1 is a schematic front view of a forming apparatus. The color image forming apparatus 1 of the present embodiment is applied to a two-component developing type color image forming apparatus.

In FIG. 1, the color image forming apparatus 1
In the main body housing 2, a paper feeding unit 10, optical writing units 20 Y, 20 M, 20 C, 20 Bk for each color of yellow (Y), magenta (M), cyan (C), and black (Bk),
Image forming units 30Y, 30M, 30C, 30B for each color
1, the transfer unit 40, the fixing unit 50, the image disorder prevention mechanism 60, and the like are housed therein.

In the color image forming apparatus 1, a paper feed unit 10 is provided at the lowermost part in the main body housing 2, and an image forming unit for each color is provided above the transfer unit 40 along a transfer unit 40 provided in a vertical direction. 30Y, 30M, 30C, and 30Bk and optical writing units 20Y, 20M, 20C, and 20Bk are provided, and a fixing unit 50 is provided above the units.

The paper supply unit 10 is provided with a plurality of recording papers (transfer papers).
Paper cassette 12 for accommodating cartridge 11 and feed roller 1
3, a registration roller pair 14, a pre-transfer guide plate 15, and the like.

The feeding roller 13 feeds out the recording paper 11 in the recording paper cassette 12 one by one to the registration roller pair 14, and the registration roller pair 14 feeds the recording paper 11 sent out by the feeding roller 13. After the timing is adjusted, the recording paper 11 is conveyed to the transfer unit 40 while being guided by the pre-transfer guide plate 15.

The transfer unit 40 includes a transfer belt (transport belt) 41, a driving roller 42, a driven roller 43, transfer members 44Y, 44M, 44C, 44Bk, and a suction roller 4.
5, transfer cleaning member 46, transfer neutralizing section 47, switching roller 48, separation member 49, and transfer unit case 40
The transfer belt 41 is formed in an endless belt shape, and is stretched between a driving roller 42 and a driven roller 43. Along this transfer belt 41, the optical writing units 20Y, 20M, 2M for the respective colors of yellow (Y), magenta (M), cyan (C) and black (Bk).
0C, 20Bk and image forming units 30Y, 30M, 30
C and 30Bk are provided. The transfer belt 41 is, for example, a seamless belt of PVDF (polyvinylidene fluoride), which is a fluororesin, and has light transmittance. Further, as the transfer belt 41, an OPH sheet which partially reflects light but has light transmittance may be used, or a polyester film or the like may be used.

The transfer unit 40 rotates the transfer belt 41 clockwise in FIG. 1 by rotating the drive roller 42 by a drive mechanism such as a motor (not shown). The recording paper 11 sent from the printer 14 is electrostatically adsorbed on the transfer belt 41 by an adsorption roller 45. That is, the suction roller 45 abuts on the transfer belt 41 at the driven roller 43 and electrostatically attracts the recording paper 11 guided and sent out from the registration roller pair 14 by the pre-transfer guide plate 15 to the transfer belt 41. The pre-transfer guide plate 15 guides the recording paper 11 so that the leading end of the recording paper 11 is conveyed between the suction roller 45 and the transfer belt 41 without colliding with the suction roller 45.

The transfer belt 41 applies the recording paper 11 electrostatically attracted by the attraction roller 45 to each of the image forming units 30Y and 3Y.
0M, 30C, and 30Bk sequentially, and the transfer unit 4
Numeral 0 denotes toner images of the respective image forming units 30Y, 30M, 30C, and 30Bk on the recording paper 11 that is attracted to and conveyed to the transfer belt 41.
4Bk, the recording paper 11 on which the toner image has been transferred is conveyed to the drive roller 42, and the transfer belt 41 is separated by the curvature separation by the drive roller 42 and the separation member 49.
And is sent to the fixing unit 50. When the curvature separation by the drive roller 42 is sufficient, the separation member 49 is unnecessary.

The transfer belt 41 that has conveyed the recording paper 11 between the drive rollers 42 is further driven to rotate, the surface of the transfer belt 41 is cleaned cleanly by the transfer cleaning member 46, and the charge is removed by the transfer charge removing unit 47.

The switching roller 48 is used for the color image forming apparatus 1.
The position of the transfer belt 41 is changed in accordance with the full-color mode and the monochrome mode provided in the image forming apparatus.
Y, 30M, 30C, 30Bk photosensitive drums 31Y,
In the monochrome mode, the transfer belt 41 is brought into contact with only the photosensitive drum 31Bk of the black (Bk) image forming unit 30Bk.

A transfer unit cover 2a is provided on the main body housing 2 of the transfer unit 40. The transfer unit cover 2a is connected to a driven roller 43 via a hinge (not shown).
It is attached to the main body casing 2 so as to be openable and closable in a direction indicated by an arrow A in FIG. The transfer unit cover 2a can be pulled up in the upper right direction indicated by an arrow B in FIG. 1, or can be opened to a horizontal position and pulled in the horizontal direction, or can be pulled forward in FIG. It is attached detachably from the housing 2.

The fixing section 50 includes a fixing roller section 51 heated to a predetermined fixing temperature, a pressing roller 52 pressed against the fixing roller section 51 with a predetermined pressing force, and a discharge roller pair 53.
The recording paper 11 conveyed between the fixing roller unit 51 and the pressure roller 52 is heated and pressed to fix the toner image on the recording paper 11 to the recording paper 11 and to form a discharge roller pair. Send to 53. The discharge roller pair 53 discharges the fixed recording paper 11 onto the discharge tray 3.

Each of the image forming units 30Y, 30M, 30
C, 30Bk are photosensitive drums 31Y, 31M, 31 that are driven to rotate counterclockwise in FIG. 1 by a driving mechanism (not shown).
C, 31Bk, charging units 32Y, 32M, 32C, 32B
k, developing units 33Y, 33M, 33C, 33Bk, static elimination units 34Y, 34M, 34C, 34Bk, cleaning units 35Y, 35M, 35C, 35Bk, etc., and a charging unit 32Y, 32M, 32C, 32Bk, a developing unit 33
Y, 33M, 33C, 33Bk and cleaning unit 35
Y, 35M, 35C, 35Bk are the photosensitive drums 31
Y, 31M, 31C, and 31Bk. Each image forming unit 30Y, 30M, 30C, 30Bk
The guide rail 36Y, as shown in FIG.
The guide rails 36Y, 36M, 36C, 36Bk are detachably mounted in 36M, 36C, 36Bk.
Is attached to the main body housing 2 so as to be slidable in the front or rear direction on the paper of FIGS. 1 and 2. Therefore, each image forming unit 30Y, 30M, 30C, 30Bk
The guide rails 36Y, 36M, 36C, and 36Bk can be pulled out and taken out of the main housing 2, and can be mounted on the main housing 2. Then, the image forming units 30Y, 30M, 30C, 3
The optical writing unit 20 for each color is located at a position corresponding to 0Bk.
Y, 20M, 20C, and 20Bk are provided.

Image forming units 30Y, 30M, 30C, 3
0Bk uniformly charges the photosensitive drums 31Y, 31M, 31C, and 31Bk by the charging units 32Y, 32M, 32C, and 32Bk, and the optical writing units 20Y, 20M, and 20B.
C, photosensitive drum 31 uniformly charged by 20Bk
The Y, 31M, 31C, and 31Bk are irradiated with a laser modulated by image data of each color to form an electrostatic latent image on the photosensitive drums 31Y, 31M, 31C, and 31Bk of each color. The developing units 33Y, 33M, 33C, and 33Bk are provided with the photosensitive drums 31Y, 31M, and 31 on which the electrostatic latent images are formed by the optical writing units 20Y, 20M, 20C, and 20Bk.
The toner of each color is supplied to C and 31Bk to form a toner image of each color.

The transfer members 44Y and 44 of the transfer unit 40
M, 44C and 44Bk are the photosensitive drums 31Y and 31
When the recording paper 11 is conveyed by the transfer belt 41 between the recording paper 11 and M, 31C, and 31Bk, a transfer electric field is applied, and the toner images of the respective colors on the photosensitive drums 31Y, 31M, 31C, and 31Bk are recorded on the recording paper 11. Transfer to

Static eliminator (static elimination means) 34Y, 34M, 34
C and 34Bk transfer the charge removing light to the photosensitive drums 31Y and 31B.
M, 31C, and 31Bk to irradiate the photosensitive drum 31
Y, 31M, 31C, and 31Bk are neutralized, and for example, a neutralization lamp or the like is used. As the static elimination units 34Y, 34M, 34C and 34Bk using the static elimination lamp, for example, an extremely small chip-shaped LED (Light Em
Itting Diode) in the longitudinal direction (photosensitive drum 31Y, 31
M, 31C, and 31Bk) are used.

The cleaning units 35Y, 35M, 35C,
35Bk is the photosensitive drum 31 whose transfer has been completed and whose charge has been removed.
Y, 31M, 31C, and 31Bk, and removes residual toner on the photosensitive drum 3.
1Y, 31M, 31C, and 31Bk are charging units 32Y, 3
It is uniformly charged by 2M, 32C, and 32Bk and is again provided for image formation.

As shown in FIG. 2, the charge removing units 34Y, 34M and 34C are connected to the adjacent image forming units 30M and 30M.
C, 30Bk, which are attached to the image forming units 30M, 30C, 30Bk on the downstream side in the conveying direction of the recording paper 11, and the charge removing section 34Bk
At a position downstream of the recording paper 11 in the transport direction of the recording paper 11, the recording paper 11 is attached to a case or a main body frame or the like of the imaging unit 30 </ b> Bk (not shown).

The image disturbance preventing mechanism 60 includes a conductive member (electric field stabilizer) 6 disposed inside the transfer belt 41.
1α, 61β, 61γ and the conductive members 61α, 61
Insulating member 6 disposed on the transfer belt 41 side of β, 61γ
2α, 62β, 62γ and image forming units 30Y, 30
Guide rails 36Y, 36M, 36 as conductive members (electric field stabilizers) disposed on the M, 30C, 30Bk side
C, 36Bk and the corresponding guide rails 36M, 36C, 36
An insulating member 63α disposed on the Bk transfer belt 41 side;
63β and 63γ.

The conductive members 61α, 61β, and 61γ are located between the photosensitive drums 31Y, 31M, 31C, and 31Bk of the image forming units 30Y, 30M, 30C, and 30Bk and the photosensitive drums 31Y, 31M, 31C, and 31Bk. Are arranged inside the transfer belt 41 over a predetermined area of the transfer belt 41, for example, a thin sheet metal is used. Insulation member 6
2α, 62β, and 62γ are formed of, for example, a black polyester film sheet sandwiching a flame-retardant material, and are attached to the surface of the conductive members 61α, 61β, and 61γ on the transfer belt 41 side with a double-sided tape or the like, or It is fixed with an adhesive. The conductive members 61α, 61β, and 61γ are connected and wired to the ground of the main body casing 2 together with the necessary members of the transfer unit 40.

Guide rails 36Y, 36M, 36C, 3
6Bk is, as described above, the image forming units 30Y and 30B.
M, 30C, and 30Bk, are formed of a conductive material, for example, a sheet metal, and are grounded to the main body housing 2 by screwing or the like, so that the image forming units 30Y and 30B
It functions as a conductive member (electric field stabilizer) on the M, 30C, 30Bk side. Transfer belt 41 of guide rails 36Y, 36M, 36C, 36Bk as this conductive member
On the side surface, insulating members 63α, 63β, 63γ are stuck with a double-sided tape or the like, or bonded and fixed with an adhesive. As the insulating members 63α, 63β, 63γ, for example, a flame-retardant material is sandwiched. It is formed of a black polyester film sheet.

The conductive members 61α, 61β, 61γ,
The image disturbance prevention mechanism 60 including the insulating members 62α, 62β, and 62γ, the guide rails 36Y, 36M, 36C, and 36Bk as the conductive members and the insulating members 63α, 63β, and 63γ is provided on the front side and the back side of the transfer belt 41. Between the toner and the conductive member 6
A vertical electric field is generated between 1α, 61β, 61γ and the guide rails 36Y, 36M, 36C, 36Bk as conductive members, and a force for moving the toner in a horizontal direction, that is, a direction parallel to the transfer belt 41 is generated. Prevent occurrence,
The electric field between the front side and the back side of the transfer belt 41 is stabilized to prevent image disturbance.

As shown in FIGS. 2 and 3 for the charge eliminating units 34M and 34Y, the charge eliminating units 34Y, 34M and 34C are provided with the image forming units 30M and 30C on the downstream side in the transport direction of the recording paper 11.
C, 30Bk guide rails 36M, 36C, 36Bk
Are attached to the insulating members 63α, 63β, and 63γ attached to the transfer belt 41 in a state of emitting static elimination light in a direction substantially parallel to the transfer belt 41. Further, the charge elimination unit 34Bk is larger than the cleaning unit 35Bk in the recording paper 1B.
At a position on the downstream side in the transport direction of the transfer belt 41, the static elimination light is attached to a case or a main body frame (not shown) of the image forming unit 30 </ b> Bk in a direction substantially parallel to the transfer belt 41.

The image forming units 30Y, 30M, 3
0C, 30Bk cleaning sections 35Y, 35M, 35
C, 35Bk are the cleaning cases 35Ya,
The surface of the transfer belt 41 side of 5Ma, 35Ca, and 35Bka is gradually inclined from the downstream side in the transport direction of the recording paper 11 to the upstream side by the necessary space of the cleaning units 35Y, 35M, 35C, and 35Bk. Inclined surface 35Yb, 35Mb, 35Cb, 35B
kb.

Therefore, the insulating members 63α, 63
neutralization units 34Y, 34M, 3 attached to β, 63γ
4C and the static elimination light emitted in a direction substantially parallel to the transfer belt 41 from the static elimination unit 34Bk is projected onto the inclined surface 3 of the cleaning cases 35Ya, 35Ma, 35Ca, and 35Bka.
Collision with 5Yb, 35Mb, 35Cb, 35Bkb,
Directly, the photosensitive drums 31Y, 31M, 31C, 31
Bk is not irradiated.

Therefore, the color image forming apparatus 1 according to the present embodiment includes the cleaning cases 35Ya, 35Ma,
35Ca, 35Bka inclined surfaces 35Yb, 35Mb, 3
5Cb and 35Bkb are replaced with the cleaning case 35Y of FIG.
The surface has a light reflection function so as to highlight the inclined surface 35Yb of FIG. Inclined surface 35Yb, 35M
b, 35Cb, and 35Bkb, for example, in order to provide the light reflecting function to the inclined surfaces 35Yb, 35Mb,
5Cb, 35Bkb, a method of resin molding with a color capable of reflecting light, for example, a white-based color, the inclined surfaces 35Yb, 35Mb,
Only the 35Cb and 35Bkb portions are resin-molded with a white color and the cleaning cases 35Ya, 35Ma, 35Ca, 3
Resin molding of other parts of 5Bka with normal black 2
A color molding method, or a cleaning case 35Ya,
35Ma, 35Ca, and 35Bka are resin-molded in normal black, and the inclined surfaces 35Yb, 35Mb, 35Cb, 35
For Bkb, various methods such as a method of attaching a white-colored separate member such as a milky-white mylar sheet or a white-colored synthetic paper coated on paper, or a method of applying a white-colored paint can be used.

In this way, the cleaning case 35
Slope 35Y of Ya, 35Ma, 35Ca, 35Bka
Assuming that b, 35Mb, 35Cb, and 35Bkb are light reflecting surfaces, the static elimination light emitted from the static elimination unit 34M in FIG. 2 is indicated by a dashed line, and the static elimination units 34Y, 34M, 34C, and 34B.
The static elimination light emitted from Bk is inclined 35Yb, 35M
b, 35Cb, and 35Bkb, and the reflected light is reflected by the recording paper 11 conveyed on the transfer belt 41,
Further, the cleaning cases 35Ya, 35Ma, 35
The reflection that the light is reflected by Ca and 35Bka is sequentially performed, and the photosensitive drums 31Y, 31M, 31C, and 3C on the upstream side are reflected.
1Bk, and the photosensitive drums 31Y, 31M, 31
C, 31Bk is neutralized. In FIG. 2, the static elimination light is indicated by a dashed line, but this expression is exaggerated, and the static elimination light is not actually a single line, but has an overall spread. proceed.

Next, the operation of the present embodiment will be described. In the color image forming apparatus 1 of the present embodiment, the charge removing units 34Y, 34M, 34C, and 34Bk that emit the charge removing light include the recording paper 1.
Image forming units 30M, 30C, 30 on the downstream side in one transport direction
Attaching to the Bk guide rails 36M, 36C, 36Bk and the main body housing 2, etc.
Transfer belt 4 of Ya, 35Ma, 35Ca, 35Bka
One side inclined surface 35Yb, 35Mb, 35Cb, 35Bk
By using b as a light reflecting surface, the color image forming apparatus 1 is reduced in size and the use efficiency of the charge removing light is improved.

That is, the color image forming apparatus 1 separates the recording paper 11 one by one from the paper supply unit 10, conveys the recording paper 11 to the transfer unit 40, and makes the transfer belt 41 of the transfer unit 40 electrostatically adsorb by the adsorption roller 45. Then, the sheet is sequentially conveyed to each of the image forming units 30Y, 30M, 30C, and 30Bk by the transfer belt 41.

Each of the image forming units 30Y, 30M, 30C,
30Bk is a charging unit 32Y, 32M, 32C, 32Bk
The photosensitive drums 31Y, 31M, 31C, 31Bk
Are uniformly charged, and the optical writing units 20Y, 20M,
Photoconductor drum 3 uniformly charged by 0C and 20Bk
A laser modulated by image data of each color is applied to 1Y, 31M, 31C and 31Bk to form an electrostatic latent image on the photosensitive drums 31Y, 31M, 31C and 31Bk of each color. Imaging units 30Y, 30M, 30C, 30B
k denotes the photosensitive drums 31Y and 31 on which the electrostatic latent images are formed.
M, 31C, and 31Bk have developing units 33Y, 33M, and 33
C and 33Bk, respectively, to supply toner of each color to form a toner image of each color.
4Y, 44M, 44C, 44Bk, and the photosensitive drum 31
The toner images of each color on Y, 31M, 31C, and 31Bk are sequentially transferred onto the recording paper 11 conveyed on the transfer belt 41 between the photosensitive drums 31Y, 31M, 31C, and 31Bk, and transferred in color. Is formed.

The color image forming apparatus 1 conveys the recording paper 11 on which the color toner image has been transferred to the drive roller 42 by the transfer belt 41, and separates the curvature by the drive roller 42 and the transfer belt by the separating member 49. The sheet is separated from the sheet 41 and sent to the fixing section 50.

In the color image forming apparatus 1, the fixing unit 50
The recording paper 11 conveyed between the fixing roller unit 51 and the pressure roller 52 is heated and pressed to fix the toner image on the recording paper 11 to the recording paper 11, and the toner image is fixed by the discharge roller pair 53. The completed recording paper 11 is transferred to the discharge tray 3
Discharge up.

On the other hand, as described above, the color image forming apparatus 1 includes the image forming units 30Y, 30M, 30C, 30C.
Bk photoconductor drums 31Y, 31M, 31C, 31Bk
From the transfer member 4 of the fixing unit 40
4Y, 44M, 44C, and 44Bk, the image is transferred onto the transfer belt 41, and the image forming units 30 are sequentially transferred by the transfer belt 41.
Y, 30M, 30C, and 30Bk, but the conductive members 61α and 61
β, 61γ and insulating members 62α, 62 disposed on the transfer belt 41 side of the conductive members 61α, 61β, 61γ.
β, 62γ and image forming units 30Y, 30M, 30C,
Consisting of guide rails 36Y, 36M, 36C, 36Bk as conductive members disposed on the 30Bk side, and insulating members 63α, 63β, 63γ disposed on the transfer belt 41 side of the guide rails 36M, 36C, 36Bk. Since the image disturbance prevention mechanism 60 is provided, a vertical electric field is generated between the toner and the conductive members 61α, 61β, 61γ and the guide rails 36Y, 36M, 36C, 36Bk as the conductive members. To prevent the generation of a force for moving the toner in the horizontal direction, that is, the direction parallel to the transfer belt 41, stabilize the electric field between the front side and the back side of the transfer belt 41, and prevent the occurrence of image disorder. I do. Therefore, image quality can be improved.

The static elimination units 34Y, 34M, 34C are:
As shown for the charge removing units 34M and 34Y in FIGS. 2 and 3, the image forming unit 30 on the downstream side in the transport direction of the recording paper 11 is used.
M, 30C, 30Bk guide rails 36M, 36C,
Insulating members 63α, 63β, 6 attached to 36Bk
3γ is attached to the transfer belt 41 in a state where the discharge light is emitted in a direction substantially parallel to the transfer belt 41. The discharge unit 34Bk is located at a position downstream of the cleaning unit 35Bk in the transport direction of the recording paper 11 and forms an image (not shown). The unit 30Bk is attached to a case or a main body frame of the unit 30Bk in a state of emitting static elimination light in a direction substantially parallel to the transfer belt 41. Further, as the static elimination units 34Y, 34M, 34C, and 34Bk,
An extremely small static elimination lamp using an LED or the like is used.

The image forming units 30Y, 30M, 3
0C, 30Bk cleaning sections 35Y, 35M, 35
C, 35Bk are the cleaning cases 35Ya,
The surface of the transfer belt 41 side of 5Ma, 35Ca, and 35Bka is gradually inclined from the downstream side in the transport direction of the recording paper 11 to the upstream side by the necessary space of the cleaning units 35Y, 35M, 35C, and 35Bk. Inclined surface 35Yb, 35Mb, 35Cb, 35B
kb, but this cleaning case 35Y
a, 35Ma, 35Ca, 35B inclined surface 35Y
b, 35Mb, 35Cb, and 35Bkb are light reflection surfaces having a light reflection function as highlighted by oblique lines on the inclined surface 35Yb of the cleaning case 35Ya in FIG.

Accordingly, as shown by the dashed line in FIG. 2, the static elimination light emitted from the static eliminator 34M is indicated by a dashed line.
The static elimination light emitted from 34M, 34C, 34Bk is reflected by the inclined surfaces 35Yb, 35Mb, 35Cb, 35Bkb, and the reflected light is reflected by the recording paper 11 conveyed on the transfer belt 41. 35
The reflection that the light is reflected by Ya, 35Ma, 35Ca, and 35Bka is sequentially performed, and the photosensitive drum 31 on the upstream side is reflected.
The photosensitive drums 31Y, 31M, 31C, and 31Bk are irradiated with light to irradiate the photosensitive drums 31Y, 31M, 31C, and 31Bk.

As a result, the charge removing units 34Y, 34M, 34
C, 34Bk can be reduced in size, and the image forming units 30Y, 30M, 30C, 30Bk have a high degree of freedom in layout and can be reduced in size, so that the color image forming apparatus 1 can be reduced in size. . The static elimination light emitted from the static elimination units 34Y, 34M, 34C, and 34Bk is efficiently transferred to the photosensitive drums 31Y, 31M, 31C, and 31B.
k, the photosensitive drums 31Y, 31M, 31C,
31Bk can be neutralized, and the static elimination units 34Y and 34Y
M, 34C, and 34Bk can be further reduced in size, and the color image forming apparatus 1 can be further reduced in size.

Further, the color image forming apparatus 1 of the present embodiment is provided with an image disorder prevention mechanism 60, and the insulating members 62α, 62β, 62γ of the image disorder prevention mechanism 60 are provided.
If the surfaces of the insulating members 62α, 62β, and 62γ do not have light reflectivity, for example, if they are applied to a black color or are formed of a black material, the insulating members 62α, 62β, and 62γ shown in FIG. As indicated by the dashed line, the lightning unit 34
The static elimination light emitted from Y, 34M, 34C, and 34Bk is irregularly reflected by the recording paper 11 conveyed on the transfer belt 41 and the insulating members 63α, 63β, and 63γ on the image forming units 30Y, 30M, 30C, and 30Bk side. Through the transfer belt 41 having a light transmitting property, and insulating members 63α, 63
Irregularly reflected between β, 63γ and the insulating members 62α, 62β, 62γ, the photosensitive drums 31M, 3M, 3B, 3C of the image forming units 30M, 30C, 30Bk on the downstream side in the transport direction of the recording paper 11
Irradiation to 1C and 31Bk can be prevented, and the image quality can be further improved.

FIGS. 5 and 6 show a second embodiment of the color image forming apparatus of the present invention. FIG. 1 shows the second embodiment of the color image forming apparatus of the present invention. FIG. 1 is a schematic front view of a color image forming apparatus 100 according to the present invention.

The present embodiment is applied to a one-component developing type color image forming apparatus, and is different from the two-component developing type color image forming apparatus 1 of the first embodiment. The only difference is that the mounting positions of the developing unit and the neutralizing unit of the unit are different.

Therefore, in the description of the present embodiment,
The same components as those of the color image forming apparatus 1 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

5 and 6, a color image forming apparatus 100 is a color image forming apparatus 1 according to the first embodiment.
Similarly to the above, inside the main body casing 2, the paper supply unit 10, the optical writing units 20Y, 20M, and 2M for each color of yellow (Y), magenta (M), cyan (C), and black (Bk).
0C, 20Bk, a transfer unit 40, a fixing unit 50, an image disorder prevention mechanism 60, and the like are housed. A paper discharge tray 3 (not shown) is formed at an upper part of the main body housing 2, and an image forming unit for each color is formed. 101Y, 101M, 101C, 1
01Bk is housed in the main body housing 2.

The image forming units 101Y, 101M, 101
C, 101Bk are the same photosensitive drums 31Y, 31M, 31C, 31Bk, and charging unit 32 as in the first embodiment.
Y, 32M, 32C, 32Bk, static elimination units 34Y, 34
M, 34C, 34Bk and cleaning units 35Y, 35
M, 35C, 35Bk, etc., as well as developing units 102Y, 102M, 102C, 102Bk, charging units 32Y, 32M, 32C, 32Bk, developing units 102Y, 102M, 102C, 102Bk, and cleaning unit 35Y, 35M, 35C, and 35Bk are disposed around the photosensitive drums 31Y, 31M, 31C, and 31Bk.

Each image forming unit 101Y, 101M, 10
As shown in FIG. 5, the image forming units 1C and 101Bk are detachably mounted on guide rails 103Y, 103M, 103C and 103Bk.
01Y, 101M, 101C, and 101Bk, optical writing units 20Y, 20M, 20
C and 20Bk are provided.

Then, the developing units 102Y, 102M, 10M
2C and 102Bk are developing unit cases 104Y, 104M, 104C and 1
04Bk, the developing rollers 105Y, 105M, 105
C, 105Bk, thin layer blades 106Y, 106M, 1
06C, 106Bk, supply rollers 107Y, 107M,
107C, 107Bk, scraping roller 108Y, 1
08M, 108C, 108Bk and agitator 109
Y, 109M, 109C, 109Bk and a developer (not shown) are stored, and the scraping rollers 108Y,
8M, 108C, and 108Bk are not necessarily necessary parts, but scraping rollers 108Y, 108M,
8C and 108Bk, in particular, as shown in FIGS.
Each of M, 104C, and 104Bk has a shape on the transfer belt 41 side protruding in the direction of the transfer belt 41. Therefore, as in the first embodiment, the static elimination unit 34
The guide rails 103Y, 103M, 103C, and 103Bk for providing Y, 34M, 34C, and 34Bk cannot have the bent shape as in the first embodiment.

Therefore, the charge removing units 34Y, 34M, 34C
The guide rails 103M, 103C, 103Bk are enlarged as shown in FIG.
At the transfer belt 41 side of the recording paper 11 and the opening 103Ma, 103Ca, 103B
ka is formed and the openings 103Ma, 103Ca, 1
The recording paper 11 is disposed obliquely in the direction of the transfer belt 41 in the upstream direction in the transport direction of the recording paper 11 so as to penetrate into 03Bka. Further, the charge removing section 34Bk is provided with a cleaning section 35B.
At a position downstream of the recording paper 11 in the conveyance direction of the recording paper 11, the static elimination light is applied to the case or the body frame of the image forming unit 30 </ b> Bk (not shown) in the upstream direction of the conveyance of the recording paper 11 in the direction of the transfer belt 41. It is attached in a state where it is emitted obliquely.

Therefore, in the color image forming apparatus 100 of the present embodiment, as shown in FIG. 5, the static elimination light of the static elimination unit 34M is indicated by a dashed line, and the static elimination units 34Y, 34M, 34C, and 34 are used.
The static elimination light emitted from Bk is reflected on the surface of the recording paper 11 conveyed on the transfer belt 41, and the cleaning cases 35Ya, 35Ma, 35Ca, and 3C of the image forming units 101Y, 101M, 101C, and 101Bk.
The reflection between 5Bka and the recording paper 11 is repeated, so that the recording paper 1 is higher than the static elimination units 34Y, 34M, 34C, and 34Bk.
The photosensitive drum 31 disposed downstream of the first conveying direction
The photosensitive drums 31Y, 31M, 31C, and 31Bk can be neutralized by irradiating the photosensitive drums 31Y, 31M, 31C, and 31Bk. In this case, each cleaning case 35Y
a, 35Ma, 35Ca, 35B inclined surface 35Y
Assuming that b, 35Mb, 35Cb, and 35Bkb are light reflecting surfaces as in the case of the first embodiment, the static elimination unit 34Y,
It is possible to further improve the light use efficiency of the static elimination light emitted from 34M, 34C, and 34Bk.

As a result, the image forming units 101Y and 101Y
The degree of freedom of M, 101C, and 101Bk can be further improved, the size can be reduced, and the color image forming apparatus 100 can be reduced in size and the image quality can be improved.

In the color image forming apparatus 100 of the present embodiment, the guide rails 103M, 103C,
103Bk has openings 103Ma, 103Ca, 103B
After opening ka, the openings 103Ma, 103Ca, 1
Since the static elimination units 34Y, 34M, and 34C are provided in 03Bka, the leakage neutralization light leaking from the rear side of the static elimination units 34Y, 34M, and 34C is indicated by an arrow H in FIG. As shown by the guide rail 103M,
103C, 103Bk and developing unit cases 104M, 104
C, 104Bk, and passes through the neutralization units 34Y, 3Y.
The photosensitive drums 31M, 31C, and 31Bk may be irradiated on the downstream side of the recording paper 11 in the conveyance direction of the recording paper 11 with respect to the recording drums 4M and 34C, and may deteriorate the image.

Therefore, as shown in FIG.
Y, 34M, and 34C are covered with shielding sheets (light shielding mechanisms) 110Y, 110M, and 110C.
The leakage neutralization light may be shielded.

By doing so, the charge removing units 34Y and 34Y
The shielding sheets 110Y, 110M, and 110C can prevent the photosensitive drums 31M, 31C, and 31Bk on the downstream side in the transport direction of the recording paper 11 from being irradiated with the leakage neutralization light from the M and 34C, thereby improving image quality. Can be done.

As shown in FIG. 8, the charge removing section 34Y,
Guide rail 10 to which 34M and 34C are attached
The static elimination units 34Y and 34 of 3M, 103C and 103Bk
M, 34C and the photosensitive drums 31M, 31C,
31Bk, guide rails 103M, 103C,
A diaphragm (light blocking mechanism) 111 that projects inward from 103Bk
M, 111C, and 111Bk may be formed.

In this manner, without providing a separate member as a light-shielding mechanism, the leakage neutralization light from the neutralization units 34Y, 34M, and 34C is transferred to the guide rails 103M, 103C, and 103Bk in the downstream direction of the recording paper 11 in the transport direction. The photosensitive drums 31M, 31C, and 31Bk pass between the unit cases 104M, 104C, and 104Bk and are located downstream of the charge removing units 34Y, 34M, and 34C in the transport direction of the recording paper 11.
To the apertures 111M, 111C, 111
Bk can be prevented, and image quality can be improved.

As described above, the invention made by the present inventor has been specifically described based on the preferred embodiments. However, the present invention is not limited to the above, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

[0082]

According to the color image forming apparatus of the first aspect of the present invention, the photoconductors for forming the toner images of the separated colors of the color image are provided in the main body housing, and are held in the guide rails. A plurality of image forming units housed in the image forming unit case are arranged along a transport belt that transports the transfer paper, and are removed from a photosensitive member of each of the image forming units on the downstream side in the transport paper transport direction by the transport belt. A static elimination unit for emitting light is provided, and when the static elimination light emitted from each of the static elimination units is used to neutralize each of the photoconductors on the upstream side in the conveyance direction of the transfer sheet, the static elimination light is emitted from at least each of the static elimination units of the imaging unit case. To the part to be irradiated with the static elimination light
Since the reflection processing is performed to reflect the static elimination light to the photoreceptor on the upstream side in the transport direction of the transfer paper of each static elimination means, the static elimination means disposed on the downstream side in the transport direction of the transfer paper from each image forming unit. The static elimination light can be used for static elimination of the photoreceptor by using the imaging unit case, and the degree of freedom of the layout of the imaging unit can be improved. The image quality can be improved while reducing the size.

According to the color image forming apparatus of the present invention, the color image forming apparatus is transported between the photosensitive members of a plurality of image forming units disposed along the transport belt. An electric field stabilizer is disposed on the opposite side of the image forming unit with the belt interposed therebetween, an insulating member is disposed on the side of the electric field stabilizer on the conveying belt, and at least the conveying belt of the guide rail holding each image forming unit case. The surface facing portion is formed of a predetermined conductive member to function as an electric field stabilizer, and an insulating member is provided on a surface of the electric field stabilizer plate on the side of the conveyor belt, and at least the conveyor belt of each insulating member is provided. The surface on the side is subjected to an anti-reflection function treatment for preventing reflection of the neutralizing light emitted from the neutralizing means, so that the electric field acting on the transfer paper can be stabilized and the electric field can be stabilized. The insulating member reflects discharging light,
The static elimination light emitted from each static elimination unit can be prevented from being incident on a photoreceptor other than the photoreceptor to be neutralized by the static elimination unit, and the image quality can be further improved while miniaturizing the entire apparatus. it can.

According to the color image forming apparatus of the present invention, the static elimination means is disposed so as to enter the opening formed in the guide rail, and the color image forming apparatus is connected to the color image forming apparatus. A light-blocking mechanism is provided to prevent the neutralizing light from passing between the guide rail and the image forming unit case and entering the photosensitive member on the downstream side in the transport direction of the transfer paper of each neutralizing means. And the degree of freedom of the layout of the image forming unit can be further improved, and the static elimination light emitted from the static elimination means passes between the guide rail and the image forming unit case to eliminate the static elimination. It is possible to prevent light from being incident on a photoreceptor other than the photoreceptor to be neutralized by the means, and to further improve the image quality while further miniaturizing the entire apparatus.

According to the color image forming apparatus of the present invention, at least a part of the guide rail on the downstream side in the transporting direction of the transfer paper from the static elimination means attached to the guide rail is formed in the image forming unit. Since the projecting structure protrudes in the direction of the case to block the passage of static elimination light, the static elimination light emitted from the static elimination means interacts with the guide rail only by changing the shape of the guide rail without using any special member. It is possible to prevent the light passing through the space between the image unit cases from being incident on a photoreceptor other than the photoreceptor to be neutralized by the static elimination means, thereby further improving the image quality at a lower cost while further miniaturizing the entire apparatus. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a color image forming apparatus according to a first embodiment of the present invention;

FIG. 2 is a front enlarged schematic configuration diagram of an image forming unit and a transfer unit of the color image forming apparatus of FIG. 1;

3 is a front enlarged configuration diagram of a magenta image forming unit of the color image forming apparatus of FIG. 1;

FIG. 4 is an enlarged front view of a cyan image forming unit showing a state in which static elimination light of the color image forming apparatus of FIG. 1 leaks to a downstream side of a recording sheet;

FIG. 5 is an enlarged front schematic configuration view of a main part of a color image forming apparatus to which a second embodiment of the color image forming apparatus of the present invention is applied.

FIG. 6 is an enlarged front view of a magenta image forming unit of the color image forming apparatus of FIG. 5;

FIG. 7 is a front enlarged configuration diagram of a magenta image forming unit that shields a static electricity removing light by attaching a shielding sheet to a static electricity removing unit of the color image forming apparatus of FIG. 5;

FIG. 8 is an enlarged front view of a magenta image forming unit for forming a diaphragm on a guide rail of the color image forming apparatus shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Color image forming apparatus 2 Main body housing 2a Transfer part cover 3 Paper discharge tray 10 Paper supply part 11 Recording paper 12 Recording paper cassette 13 Feeding roller 14 Registration roller pair 15 Pre-transfer guide plate 20Y, 20M, 20C, 20Bk Optical writing Units 30Y, 30M, 30C, 30Bk Image forming units 31Y, 31M, 31C, 31Bk Photoconductor drums 32Y, 32M, 32C, 32Bk Charging units 33Y, 33M, 33C, 33Bk Developing units 34Y, 34M, 34C, 34Bk Static eliminating units 35Y, 35M, 35C, 35Bk Cleaning section 35Ya, 35Ma, 35Ca, 35Bka Cleaning case 35Yb, 35Mb, 35Cb, 35Bkb Inclined surface 36Y, 36M, 36C, 36Bk Guide rail 40 Transfer unit 41 Transfer belt 42 Drive low 43 Followed Rollers 44Y, 44M, 44C, 44Bk Transfer Member 45 Suction Roller 46 Transfer Cleaning Member 47 Transfer Elimination Unit 48 Switching Roller 49 Separation Member 40a Transfer Unit Case 50 Fixing Unit 51 Fixing Roller Unit 52 Pressure Roller 53 Discharge Roller pair 60 Image Disturbance prevention mechanism 61α, 61β, 61γ Conductive member 62α, 62β, 62γ Insulating member 63α, 63β, 63γ Insulating member 100 Color image forming apparatus 101Y, 101M, 101C, 101Bk Image forming unit 102Y, 102M, 102C, 102Bk Developing unit 103Y , 103M, 103C, 103Bk Guide rails 103Ya, 103Ma, 103Ca, 103Bka
Opening 104Y, 104M, 104C, 104Bk Developing unit case 105Y, 105M, 105C, 105Bk Developing rollers 106Y, 106M, 106C, 106Bk Thin layer blades 107Y, 107M, 107C, 107Bk Supply rollers 108Y, 108M, 108C, 108Bk Scraping rollers 109Y, 109M, 109C, 109Bk Agitator 110Y, 110M, 110C Shielding sheet 111M, 111C, 111Bk Aperture unit

Claims (4)

[Claims] A plurality of image forming units each having a photosensitive member for forming a toner image of each color of a color image in a main body housing and housed in an image forming unit case held in a guide rail. Discharging means are arranged along a transport belt that transports the transfer paper, and static elimination means that emits static elimination light on the downstream side in the transport direction of the transfer paper by the transport belt from the photoreceptor of each image forming unit are provided, respectively. A color image forming apparatus configured to neutralize each of the photoconductors on an upstream side in a transport direction of the transfer sheet with the static elimination light emitted from each of the static elimination units, wherein the image forming unit case emits light from at least each of the static elimination units; The portion irradiated with the neutralization light is subjected to a reflection function process for reflecting the neutralization light to the photosensitive member on the upstream side in the transfer paper transport direction of the neutralization means. Color image forming apparatus according to. 2. The image forming apparatus according to claim 1, wherein the color image forming apparatus includes the plurality of image forming units disposed along the transport belt and the image forming unit sandwiching the transport belt between the photosensitive members. An electric field stabilizer is disposed on the side opposite to the unit, an insulating member is disposed on the side of the electric belt on the side of the transport belt, and at least faces the transport belt of the guide rail holding each of the image forming unit cases. The portion is formed of a predetermined conductive member to function as an electric field stabilizer, and an insulating member is disposed on the surface of the electric field stabilizer plate on the side of the conveyor belt, and at least a portion of each of the insulating members on the side of the conveyor belt. 2. The color image forming apparatus according to claim 1, wherein the surface has been subjected to an anti-reflection function processing for preventing reflection of the charge removing light emitted from the charge removing unit. 3. The color image forming apparatus according to claim 2, wherein said static eliminator is disposed so as to penetrate into an opening formed in said guide rail. 2. The image forming apparatus according to claim 1, further comprising a light-blocking mechanism that prevents the charge removing unit from entering the photosensitive member downstream of the transfer sheet in the conveyance direction of the transfer sheet through an image unit case. 3. The color image forming apparatus according to 2. 4. The light-shielding mechanism according to claim 1, wherein at least a part of the guide rail on the downstream side in the transport direction of the transfer sheet from the static elimination means attached to the guide rail projects toward the image forming unit case. 4. A color image forming apparatus according to claim 3, wherein said color image forming apparatus has a protruding structure for preventing the passage of a color image.