JP2004053865A - Full-color image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a full color image forming apparatus which securely feeds a printing medium from a sheet feeding position to a fixing device, and which facilitates the process when the paper jamming occurs. <P>SOLUTION: In the full color image forming apparatus according to the present invention, a lower paper guide member means is provided to a lower case of an intermediate transfer body unit equipped with a plurality of rollers which winds and supports an intermediate transfer belt. An upper paper guide member means is provided to an upper case of the intermediate transfer body unit. A transfer means is provided in the position facing the intermediate transfer body unit. A paper guide member is provided in printing medium feeding position before and behind the transfer means and on the side of the intermediate transfer body unit. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a full-color image forming apparatus including an intermediate transfer unit.
[0002]
[Prior art]
A conventional image forming apparatus will be described with reference to FIG. A full-color image forming apparatus for superimposing colors using toners of a plurality of colors includes a plurality of developing devices 4 for storing toners colored in yellow (Y), magenta (M), cyan (C), and black (K). The photosensitive member 1 is charged by the charger 2, then an electrostatic latent image is formed by the exposure device 3, and the toner of each color is attached to the electrostatic latent image on the photosensitive member 1 by the developing device 4. A toner image is formed, and a toner image of each color on a photosensitive member is sequentially transferred to an intermediate transfer drum 14 serving as an intermediate transfer member to form a full-color toner image. Then, the print medium is supplied between the transfer means 15 and the intermediate transfer drum 14 to transfer the toner image onto the print medium, and the fixing device 11 fixes the toner on the print medium to obtain a print image. The toner remaining on the intermediate transfer drum 14 is cleaned by the cleaner 12, and the next printing is performed.
[0003]
In a conventional full-color image forming apparatus, a guide for guiding a print medium is attached to an apparatus frame, and an intermediate transfer drum 14 as an intermediate transfer body is disposed in a central portion of the apparatus. Alternatively, the intermediate transfer drum 14 is mounted from an axial opening of the intermediate transfer body. For this reason, when the printing medium such as paper is jammed halfway, the intermediate transfer drum 14 and the like need to be detached when removing and restoring.
[0004]
[Problems to be solved by the invention]
In a conventional electrophotographic image forming apparatus, when a printing medium is clogged in a path from paper feeding to fixing, it is necessary to attach and detach components such as the intermediate transfer drum 14, which is troublesome. Further, in a conventional electrophotographic image forming apparatus, a guide for guiding a print medium is attached to an apparatus frame, and the number of parts is large.
[0005]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a full-color image forming apparatus capable of reliably feeding a print medium from a paper feeding position to a fixing device and easily processing even when a paper jam or the like occurs.
[0006]
[Means for Solving the Problems]
In the full-color image forming apparatus of the present invention, a transfer unit is provided at a position facing the intermediate transfer unit, and a paper guide member is provided on the side of the intermediate transfer unit at a printing medium transport position before and after the transfer unit.
[0007]
A full-color image forming apparatus according to the present invention includes a photoconductor, a charger for charging the photoconductor, an exposure device for forming an electrostatic latent image on the charged photoconductor, and a toner image formed from the electrostatic latent image. A belt-shaped full-color toner image formed by sequentially superimposing a plurality of yellow, magenta, cyan, and black color toner images and four developing units each containing four color toners of yellow, magenta, cyan, and black. An intermediate transfer body unit formed on the intermediate transfer body, a transfer unit for transferring a full-color toner image to a print medium, and a fixing device for fixing the toner to the print medium, wherein the intermediate transfer body unit includes an intermediate transfer belt. And a lower case. The lower case has a lower paper guide member.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0009]
(Example 1)
FIG. 1 shows a full-color image forming apparatus of the present embodiment. 1, the same reference numerals as those in FIG. 2 denote the same components. The full-color image forming apparatus according to the present embodiment includes a belt-shaped photosensitive member 1 and an intermediate transfer unit 5 having a belt-shaped intermediate transfer member, and includes yellow (Y), magenta (M), and cyan (C). ), Black (K), a multi-rotation type full-color image forming apparatus that forms a toner image on a photoreceptor and transfers the toner image to an intermediate transfer member, and superimposes a plurality of color toner images on the intermediate transfer member to obtain a multicolor print image. It is.
[0010]
In the full-color image forming apparatus of the present embodiment, the first transfer is performed between the belt-shaped photoreceptor 1 and the intermediate transfer member, and a paper, an OHP sheet, or the like is provided between the intermediate transfer member and the transfer roller serving as the transfer unit 10. The second transfer is performed by moving the print medium. In the full-color image forming apparatus of this embodiment, in order to increase the nip in order to perform good transfer in the first transfer, the intermediate transfer member is pushed into the belt-shaped photosensitive member 1 supported by a plurality of shafts. To
[0011]
As shown in FIG. 3, the intermediate transfer body unit 5 of the full-color image forming apparatus according to the present embodiment includes a transfer roller including a first roller 17 having a large diameter and a second roller 18 having a smaller diameter than the first roller 17. The first roller 17 and the second roller 18 are supported by a side plate 19. In FIG. 3, a U-shaped notch formed on the second roller side of the side plate 19 is a guide groove serving as a positioning alignment unit 20 for positioning the intermediate transfer body unit 5 and the transfer roller of the transfer unit 10.
[0012]
In the full-color image forming apparatus of the present embodiment, an opening is provided in the vertical direction with respect to the transfer belt 16 with which the transfer roller of the intermediate transfer body unit 5 comes in contact in order to replace and remove the transfer means 10 and the intermediate transfer body unit 5. And an opening cover 13 that can be opened and closed at the opening. The provision of the opening and the opening cover 13 can normally cover the intermediate transfer member, and can prevent entry of dust and generation of scratches. At this time, the removal of the intermediate transfer body unit 5 is the direction A indicated by the arrow in FIG. 1 and is the direction in which components such as the transfer roller of the transfer unit 10 are arranged. In order to remove the intermediate transfer body unit 5 in the direction A, a certain direction of the transfer means 10 must be set to the opening of the main body. This portion is a position through which a print medium such as paper passes, and the components are The direction is relatively small and the opening is easily formed.
[0013]
In order to reduce the size of the image forming apparatus, in the conventional full-color image forming apparatus shown in FIG. 2, the distance between the storage container 8 for storing the print medium and the fixing device 11 for fixing the toner is short. On the other hand, in the full-color image forming apparatus of the present embodiment shown in FIG. 1, the fixing device 11 is shifted upward in the intermediate transfer process device to secure an interval between the storage container and the fixing device, thereby providing a path along which the print medium moves. Since the opening of the image forming apparatus is disposed and the intermediate transfer body unit 5 can be attached and detached substantially perpendicularly to the moving direction of the print medium, the intermediate transfer body can be easily taken out.
[0014]
As shown in FIG. 1, in the present embodiment, the storage container 8 is disposed below the image forming apparatus, and the fixing device 11 is disposed above the print medium feeding device 9 so that the intermediate transfer body unit is disposed substantially horizontally. Since the intermediate transfer unit 5 can be detached, the intermediate transfer unit 5 weighing about 5 to 6 kg can be easily taken out.
[0015]
FIG. 4 shows the details of the intermediate transfer unit 5. As shown in FIG. 4, a first roller 17 and a second roller 18 that support the transfer belt 16 are supported by a side plate 19, and further, the side plate 19, the first roller 17, the second roller 18 Is provided with a lower case 22 for supporting the lower case. The lower case 22 is made by injection molding a synthetic resin to reduce weight and labor. In this lower case 22, a lower paper guide member 21 is arranged as shown in FIG.
[0016]
The lower paper guide member 21 is disposed below the second roller 18 of the lower case 22, through which paper as a print medium or an OHP sheet passes and is sandwiched between the second roller 18 and the transfer roller. Go. The lower paper guide member 21 has a fin shape integrally molded with the lower case 22, and is arranged at least at three positions on both sides corresponding to the width of the print medium and at the center.
[0017]
The fin-shaped members of the lower paper guide member 21 are arranged in parallel with each other, and each fin-shaped member extends along the sheet conveyance direction as shown in FIG. As shown in FIG. 4, the lower paper guide member 21 has a shape in which a distal end portion of a fin-shaped member is notched in a concave shape. The lower paper guide member 21 is arranged at a position where the main body is fed, and may be installed closer to the paper feeder 9 than the transfer roller. Since the transfer roller and the second roller 18 (small roller) of the intermediate transfer body unit 5 are nipped in parallel, when paper as a print medium enters the nip portion, the paper is fed simultaneously with the entry. There must be. Therefore, the curved surface surrounding the leading end of the fin-shaped member of the lower paper guide member 21 has a value such that there is no unevenness or substantially no unevenness in the direction along the axis of the transfer roller, and It does not bend in the direction perpendicular to the transport direction. In the present embodiment, the lower paper guide member 21 is formed integrally with the lower case 22. However, the lower paper guide member 21 is formed separately from the lower case 22, and a reinforcing member of a metal plate such as an iron plate is provided on the back thereof. It may be arranged and attached to the lower case 22.
[0018]
The bottom shape of the lower case 22 is determined according to the shape of the lower inner surface of the frame of the full-color image forming apparatus. However, if the flat surface is horizontal unless there is a special reason, when the intermediate transfer body unit 5 is detached from the main body, it is attached to the main body. It can be placed in almost the same direction as at the time, and maintenance is improved.
[0019]
(Example 2)
This embodiment is the same as the first embodiment except that the upper paper guide member 24 is disposed above the lower paper guide member 21 in the intermediate transfer body unit 5 as shown in FIG. In the present embodiment, the upper paper guide member 24 is provided so that the print medium such as paper that has passed through the transfer roller is not fed straight upward and the print medium is fixed to the transfer belt 16 even when the paper falls down to the transfer belt 16 side. I will guide you surely. In this embodiment, the upper case 23 to which the upper paper guide member 24 is attached is fixed to the side plate 19 of the intermediate transfer body unit 5. The upper paper guide member 24 includes a fin-shaped member integrally formed with the upper case 23, and is disposed at least at three places, namely, on both sides corresponding to the width of the print medium and at the center. Further, as shown in FIG. 5, the upper paper guide member 24 has a shape in which a tip portion of a fin-shaped member is cut out in a concave shape. The number of fin-shaped members arranged on the upper paper guide member 24 may be equal to or different from the number of fin-shaped members arranged on the lower paper guide member 21.
[0020]
In this embodiment, the curved surface surrounding the leading end of the fin of the upper paper guide member 24 has a value such that there is no unevenness or substantially no unevenness in the direction along the axis of the transfer roller, and It does not bend in the direction perpendicular to the transport direction. In this embodiment, the upper paper guide member 24 is formed integrally with the upper case 23. However, the upper paper guide member 24 is formed separately from the upper case 23, and a metal plate such as an iron plate is disposed as a reinforcing member on the back thereof. Then, it may be attached to the upper case 23. Further, in the present embodiment, as shown in FIG. 1, the second roller 7 of the intermediate transfer body unit 5 protrudes from both the lower paper guide member 21 and the upper paper guide member 24, and is transferred to a print medium. And it can be easily transported to the fixing device 11.
[0021]
Thus, in this embodiment, since the lower paper guide member 21 and the upper paper guide member 24 shown in FIG. 5 are provided, the paper can be stably guided from the paper feed position to the fixing device 11. Further, since the transfer means 10 using a transfer roller or the like is opened apart from the intermediate transfer body unit 5, processing such as paper jam can be easily performed.
[0022]
In the present embodiment, the upper paper guide member 24 and the lower paper guide member 21 are provided in the intermediate transfer body unit 5. Needless to say, the paper can be stably guided to the container 11.
[0023]
【The invention's effect】
According to the present invention, since the intermediate transfer body unit of the full-color image forming apparatus includes the paper guide member, the print medium is hardly clogged, and even if it occurs, the print medium can be easily removed.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a full-color image forming apparatus according to a first embodiment.
FIG. 2 is an explanatory diagram of a conventional full-color image forming apparatus.
FIG. 3 is an explanatory diagram of an intermediate transfer body unit according to the first embodiment.
FIG. 4 is an explanatory diagram of a lower paper guide member according to the first embodiment.
FIG. 5 is an explanatory diagram of an upper paper guide member according to the second embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Photoreceptor, 2 ... Charger, 3 ... Exposure apparatus, 4 ... Developing device, 5 ... Intermediate transfer body unit, 6, 17 ... 1st roller, 7, 18 ... 2nd roller, 8 ... Storage container, Reference numeral 9: paper feeder, 10, 15: transfer means, 11: fixing device, 12: cleaner, 13: opening cover, 14: intermediate transfer drum, 16: transfer belt, 19: side plate, 20: positioning and aligning means, 21 ... lower paper guide member, 22 ... lower case, 23 ... upper case, 24 ... upper paper guide member.

Claims (7)

A photoconductor, a charger for charging the photoconductor, an exposure device for forming an electrostatic latent image on the charged photoconductor, and yellow, magenta, cyan, and black for converting the electrostatic latent image into a toner image Four developing units each containing a color toner, and an intermediate transfer unit for forming a full-color toner image on a belt-shaped intermediate transfer member by sequentially superimposing the four color toner images of yellow, magenta, cyan and black A full-color image forming apparatus comprising: a transfer unit that transfers a full-color toner image to a print medium; and a fixing device that fixes the toner on the print medium.
A full-color image forming apparatus, wherein the intermediate transfer body unit includes a plurality of rollers for winding and supporting an intermediate transfer belt, and a lower case, and the lower case includes a lower paper guide member. A photoconductor, a charger for charging the photoconductor, an exposure device for forming an electrostatic latent image on the charged photoconductor, and yellow, magenta, cyan, and black for converting the electrostatic latent image into a toner image An intermediate transfer unit for forming a full-color toner image on a belt-like intermediate transfer member by sequentially superimposing four developing units each containing a color toner and the four color toner images of yellow, magenta, cyan and black. A full-color image forming apparatus comprising: a transfer unit that transfers a full-color toner image to a print medium; and a fixing device that fixes the toner on the print medium.
A full-color image forming apparatus, wherein the intermediate transfer unit includes a plurality of rollers for winding and supporting an intermediate transfer belt, and an upper case, and the upper case includes an upper paper guide member. 2. The full-color image forming apparatus according to claim 1, wherein the lower paper guide member is a plurality of fin-shaped members, and the fin-shaped members are arranged in parallel with each other, and the fin-shaped members are arranged along a conveying direction of a print medium. A full-color image forming apparatus, wherein a fin-shaped member extends. 4. The full-color image forming apparatus according to claim 3, wherein the fin-shaped member has a shape in which a tip portion is concavely notched. The full-color image forming apparatus according to claim 1, wherein the intermediate transfer body unit includes an upper case, and the upper case includes an upper paper guide member. 6. The full-color image forming apparatus according to claim 5, wherein the roller that winds and supports the intermediate transfer belt protrudes toward the transfer unit from either the lower paper guide member or the upper paper guide member. Full color image forming device. 2. The full-color image forming apparatus according to claim 1, wherein an opening is disposed in a conveyance path of the print medium, and the intermediate transfer body unit can be detached from the opening.

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