JP2007148058A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily set an intermediate transfer belt of a transfer unit and an image carrier of an imaging cartridge at proper positions, in an image forming apparatus equipped with the transfer unit provided with the intermediate transfer belt and the imaging cartridge, provided with the image carrier where a toner image to be transferred to the intermediate transfer belt is formed. <P>SOLUTION: The image forming apparatus, equipped with the transfer unit 10 provided with at least the endless intermediate transfer belt 13 driven by a rotary roller 12 in a housing 11 and the imaging cartridge 20 provided with at least the image carrier 22, where the toner image to be transferred to the intermediate transfer belt is formed, is provided with guiding sections 15 and 16 for loading the imaging cartridge in the transfer unit so that the image carrier faces the intermediate transfer belt. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a copying machine or a printer, and in particular, a transfer unit in which an endless intermediate transfer belt driven by at least a rotating roller is provided in a housing, and at least transferred to the intermediate transfer belt. An image forming apparatus including an imaging cartridge provided with an image carrier on which a toner image to be formed is provided, characterized in that positioning of the intermediate transfer belt and the image carrier can be performed easily and appropriately It is.

  Conventionally, various types of image forming apparatuses such as copying machines and printers have been used.

  In recent years, as an image forming apparatus for forming a full-color image, toner images having different colors are formed on a plurality of image carriers, and the toner images formed on the image carriers are transferred to an intermediate transfer belt. A full-color toner image is formed on the intermediate transfer belt, and the full-color toner image thus formed on the intermediate transfer belt is transferred onto a recording paper or the like.

  Further, in the image forming apparatus as described above, in order to be able to easily set each of the image carrier and the intermediate transfer belt in the image forming apparatus, and to easily replace them, The intermediate transfer belt and the image carrier are each unitized, for example, a transfer unit in which an endless intermediate transfer belt driven by at least a rotating roller is provided in a housing, and the intermediate transfer An imaging cartridge provided with an image carrier provided with an image carrier for transferring a toner image onto a belt is used (for example, see Patent Document 1).

  Here, in the image forming apparatus using the transfer unit and the imaging cartridge as described above, when the transfer unit and the imaging cartridge are set in the image forming apparatus, the transfer unit and the imaging cartridge are The image forming apparatus is mounted on each mounting portion provided in the image forming apparatus.

However, when the transfer unit and the imaging cartridge are mounted on the respective mounting portions provided in the image forming apparatus as described above, even if a slight shift occurs in each mounting position, the transfer unit There is a problem that the positional relationship between the intermediate transfer belt provided on the image transfer member and the image carrier provided on the imaging cartridge is shifted, and satisfactory image formation cannot be performed. In addition, when the mounting portions for mounting the transfer unit and the imaging cartridge are separately provided in the image forming apparatus as described above, there is a problem that the cost increases and the apparatus becomes large.
JP 2001-356546 A

  The present invention is provided with a transfer unit in which an endless intermediate transfer belt driven by at least a rotating roller is provided in a housing, and an image carrier on which at least a toner image to be transferred to the intermediate transfer belt is formed. An object of the present invention is to solve the above problems in an image forming apparatus including an imaging cartridge.

  That is, according to the present invention, in the image forming apparatus as described above, the intermediate transfer belt provided in the transfer unit and the image carrier provided in the imaging cartridge can be easily set at appropriate positions. An object of the present invention is to reduce the manufacturing cost of an image forming apparatus without increasing the size.

  In the present invention, in order to solve the above-described problems, a transfer unit in which an endless intermediate transfer belt driven at least by a rotating roller is provided in a housing, and a toner image to be transferred to at least the intermediate transfer belt. In an image forming apparatus comprising an imaging cartridge provided with an image carrier on which an image is formed, the image carrier provided on the imaging cartridge is opposed to an intermediate transfer belt provided on the transfer unit. Thus, a mounting guide portion for mounting the imaging cartridge to the transfer unit is provided.

  Here, in the image forming apparatus described above, toner images having different colors are formed on a plurality of image carriers, and the toner images formed on the image carriers are transferred to intermediate transfer belts. In the case of forming a full-color image by forming a full-color toner image, the transfer unit is provided with a plurality of mounting guide portions for mounting the imaging cartridge.

  In the present invention, a transfer unit in which an endless intermediate transfer belt driven by at least a rotating roller is provided in a housing, and an image carrier on which at least a toner image to be transferred to the intermediate transfer belt is formed are provided. In the image forming apparatus having the imaging cartridge, the mounting guide portion for mounting the imaging cartridge is provided in the transfer unit, so that the transfer unit and the imaging cartridge are directly positioned by the mounting guide portion. The imaging cartridge is mounted in an appropriate position with respect to the transfer unit, and the image carrier provided in the imaging cartridge is easily placed in an appropriate position so as to face the intermediate transfer belt provided in the transfer unit. To be set accurately , Good image formation is allow stable.

  In the image forming apparatus of the present invention, the imaging cartridge provided with the image carrier is mounted on the mounting guide portion of the transfer unit provided with the intermediate transfer belt as described above. In addition, it is not necessary to provide separate mounting portions for mounting the transfer unit and the imaging cartridge in the image forming apparatus, thereby reducing the manufacturing cost and increasing the size of the apparatus.

  In the image forming apparatus of the present invention, when a plurality of mounting guide portions for mounting the imaging cartridge is provided in the transfer unit, an image carrier provided in each imaging cartridge is provided in the middle of the transfer unit. It can be easily set at an appropriate position with respect to the transfer belt, and good full-color image formation can be stably performed.

  Hereinafter, an image forming apparatus according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings. The image forming apparatus according to the present invention is not limited to the one shown in the following embodiment, and can be implemented with appropriate modifications within a range not changing the gist thereof.

(Embodiment 1)
In the image forming apparatus according to the first embodiment, as shown in FIGS. 1 and 2, as the transfer unit 10, the front side and the back side of the longitudinal direction end face and the bottom face of the housing 11 with the bottom face open are provided. A pair of rotating rollers 12 is provided between the side plates 11 a, and an endless intermediate transfer belt 13 is provided so as to span the pair of rotating rollers 12. One end side of the intermediate transfer belt 13 is connected to the housing 11. A plurality of (four in the example shown in the figure) primary transfer rollers 14 are provided on the lower belt 13a of the intermediate transfer belt 13 at appropriate intervals in the longitudinal direction while projecting from the opened end face. I try to use something.

  In the transfer unit 10, the mounting guide portion for mounting the imaging cartridge 20 serves as a pair of opposing saddle-like shapes along a direction orthogonal to the driving direction of the intermediate transfer belt 13. A plurality (four in the example shown in the figure) is provided so as to correspond to the primary transfer roller 14 so as to span the lower portions of the side plate 11a on the front side and the back side of the housing 11 in the housing 11. Yes.

  On the other hand, in the imaging cartridge 20 mounted on the transfer unit 10, as shown in FIGS. 3 and 4, a cylindrical image carrier 21 on which a toner image to be transferred to the intermediate transfer belt 13 is formed. And a charging roller 22 for charging the surface of the image carrier 21 in the imaging cartridge 20. The charging roller 22 charges the surface of the image carrier 21 in the imaging cartridge 20. A cleaning brush 23 that removes toner remaining on the surface of the image carrier 21 and a static elimination lamp 24 that neutralizes the surface of the image carrier 21 are provided.

  In the imaging cartridge 20, a side opening 20 b is formed on the side of the developing device 30 that supplies toner to the image carrier 21 so that the developing roller 31 can face the image carrier 21. On the upper surface of the imaging cartridge 20, an engaging portion 25 that is engaged with a pair of opposing hook-shaped engaging portions 15 provided on the housing 11 of the transfer unit 10 protrudes on both sides. Provided.

  In the image forming apparatus according to the first embodiment, as shown in FIG. 5, the engaging portion 25 provided so as to protrude on both sides of the imaging cartridge 20 is provided in the housing 11 of the transfer unit 10. The image carrier 21 provided in the imaging cartridge 20 is inserted along the pair of opposing hook-shaped locking portions 15, and the lower side of the intermediate transfer belt 13 provided in the transfer unit 10. The imaging cartridge 20 is mounted on the transfer unit 10 so as to face the primary transfer roller 14 via the belt 13a. Further, the developing device 30 is provided so that the developing roller 31 in the developing device 30 faces the image carrier 21 through the side opening 20 b provided in the imaging cartridge 20.

  Here, in the image forming apparatus according to the first embodiment, as shown in FIG. 6, each of the engaging portions in a pair of opposing hooks provided in the housing 11 of the transfer unit 10 as described above. 15 is mounted with the above-described imaging cartridge 20, and an image carrier 21 provided in each imaging cartridge 20 is connected to each primary transfer roller 14 via a belt 13 a below the intermediate transfer belt 13 provided in the transfer unit 10. And a developing device 30 in which toner of different colors is accommodated for each imaging cartridge 20, and a developing roller 31 in each developing device 30 is connected to an image carrier 21 provided in each imaging cartridge 20. Try to face each other.

  In the image forming apparatus according to the first embodiment, when forming a full-color image, the image carrier 21 is rotated in each imaging cartridge 20, and the surface of the image carrier 21 is charged by the charging roller 22. Then, the surface of the image carrier 21 charged in this way is exposed according to image information by the exposure device 4 provided in the image forming apparatus, and an electrostatic latent image is formed on the surface of the image carrier 21. Form. Then, toners of different colors are supplied from the developing rollers 31 provided in the developing devices 30 to the image carriers 21 in the imaging cartridges 20 on which the electrostatic latent images are formed in this way. Toner images having different colors are formed on the surface of the image carrier 21 in the cartridge 20.

  Next, the toner images having different colors formed on the surface of the image carrier 21 in each imaging cartridge 20 are sequentially applied to the intermediate transfer belt 13 by the primary transfer roller 14 provided in the transfer unit 10. And a full-color toner image is formed on the intermediate transfer belt 13. On the other hand, in each of the imaging cartridges 20 described above, after the toner remaining on the surface of the image carrier 21 is removed by the cleaning brush 23, the surface of the image carrier 21 is neutralized by the static elimination lamp 24, and then again. The surface of the image carrier 21 is charged by the charging roller 22 described above.

  In the image forming apparatus, the recording medium 6 accommodated in the paper feed tray 5 is guided between the intermediate transfer belt 13 on which the full-color toner image is formed and the secondary transfer roller 7 as described above. The full color toner image formed on the intermediate transfer belt 13 is transferred to the recording medium 6 by the secondary transfer roller 7, and the full color toner image transferred to the recording medium 6 is transferred to the recording medium 6 by the fixing device 8. The image is fixed and discharged from the image forming apparatus.

  In the image forming apparatus according to this embodiment, the charging roller 22 is used as a charging device for charging the image carrier 21 as the imaging cartridge 20, and the cleaning device removes the toner remaining on the surface of the image carrier 21. Although the cleaning brush 23 is used, the charging device for charging the image carrier 21 and the cleaning device for removing the toner remaining on the surface of the image carrier 21 are not limited to the above. For example, FIG. As shown, a scorotron charging device 22 a is used as a charging device for charging the image carrier 21, or a cleaning blade 23 a is used as a cleaning device for removing toner remaining on the surface of the image carrier 21. It is also possible to make it press-contact with.

(Embodiment 2)
In the image forming apparatus according to the second embodiment, as shown in FIG. 8, as the transfer unit 10, the front and back side plates 11 a are disposed at both ends in the longitudinal direction of the housing 11 in which the end face and the top face in the longitudinal direction are opened. A pair of rotating rollers 12 is provided between them, and an endless intermediate transfer belt 13 is provided so as to span the pair of rotating rollers 12. One end of the intermediate transfer belt 13 is opened on the housing 11. The intermediate transfer belt 13 is provided with a plurality of (four in the example shown in the figure) primary transfer rollers 14 provided at appropriate intervals in the longitudinal direction below the upper belt 13b of the intermediate transfer belt 13. Like that.

  Further, in the transfer unit 10 described above, guide grooves 16 extending downward from the upper surfaces of the housing 11 opened on the side plates 11a on the front side and the rear side are provided as mounting guide portions for mounting the imaging cartridge 20, respectively. A plurality (four in the example shown in the figure) are provided so as to correspond to the primary transfer roller 14 with an appropriate interval in the longitudinal direction, and the developing device 30 with an appropriate interval with these guide grooves 16. Similarly, a plurality of (four in the example shown in the figure) second guide grooves 17 for attaching the toner to the transfer unit 10 are provided.

  On the other hand, in the imaging cartridge 20 mounted on the transfer unit 10, as shown in FIGS. 9 and 10, a cylindrical image carrier 21 on which a toner image to be transferred to the intermediate transfer belt 13 is formed. Is rotatably provided so as to protrude downward from the corner of the bottom thereof, and in the imaging cartridge 20, a scorotron charging device 22a for charging the surface of the image carrier 21 and an image carrier 21 are provided. A cleaning blade 23 a that removes toner remaining on the surface of the image carrier 21 by being pressed against the surface of the image carrier 21, and a static elimination lamp 24 that neutralizes the surface of the image carrier 21 are provided.

  Further, in this imaging cartridge 20, the protruding portion 26 to be inserted into the guide groove 16 provided in the side plate 11a on the front side and the back side of the transfer unit 10 is protruded to the front side and the back side. Provided.

  Also in the developing device 30, as shown in FIG. 11, the locking protrusion 32 that is inserted into the second guide groove 17 provided in the side plate 11 a on the front side and the back side of the transfer unit 10. Is provided so as to protrude from the front side and the back side.

  In the image forming apparatus according to the second embodiment, as shown in FIG. 12, each imaging cartridge 20 is placed in each guide groove 16 provided in the side plate 11a on the front side and the back side of the transfer unit 10. The above-described protrusions 26 provided on the image cartridges 20 are inserted, the respective imaging cartridges 20 are lowered along the guide grooves 16 and guided into the housing 11 of the transfer unit 10, and the image carriers 21 provided on the respective imaging cartridges 20. However, each imaging cartridge 20 is mounted on the transfer unit 10 so as to face each primary transfer roller 14 via the belt 13b on the upper side of the intermediate transfer belt 13 provided in the transfer unit 10.

  Further, the locking protrusions 32 provided in the developing device 30 are inserted into the second guide grooves 17 provided in the side plates 11a on the front side and the back side of the transfer unit 10, respectively. The developing device 30 is lowered along the second guide groove 17 and guided into the housing 11 of the transfer unit 10, and the developing roller 31 provided in each developing device 30 is an image carrier provided in each imaging cartridge 20. Each developing device 30 is set in the housing 11 of the transfer unit 10 so as to face the 21.

  Here, in forming a full-color image using the image forming apparatus according to the second embodiment, the image carrier 21 is rotated in each imaging cartridge 20, and the surface of the image carrier 21 is placed on the scorotron charging device 22a. Then, the surface of each image carrier 21 charged as described above is exposed according to the image information by an exposure device (not shown) provided above the transfer unit 10, An electrostatic latent image is formed on the surface of the image carrier 21. Then, toners of different colors are supplied from the developing rollers 31 provided in the developing devices 30 to the image carriers 21 in the imaging cartridges 20 on which the electrostatic latent images are formed in this way. Toner images having different colors are formed on the surface of the image carrier 21 in the cartridge 20.

  Next, the toner images having different colors formed on the surface of the image carrier 21 in each imaging cartridge 20 are sequentially applied to the intermediate transfer belt 13 by the primary transfer roller 14 provided in the transfer unit 10. And a full-color toner image is formed on the intermediate transfer belt 13. On the other hand, in each of the imaging cartridges 20 described above, after the toner remaining on the surface of the image carrier 21 is removed by the cleaning blade 23a, the surface of the image carrier 21 is neutralized by the static elimination lamp 24, and then again. The surface of the image carrier 21 is charged by the scorotron charging device 22a.

  Thereafter, although not shown, like the image forming apparatus of the first embodiment, the recording medium 6 accommodated in the paper feed tray 5 is transferred to the intermediate transfer belt on which the full-color toner image is formed as described above. 13 and the secondary transfer roller 7, the full color toner image formed on the intermediate transfer belt 13 is transferred to the recording medium 6 by the secondary transfer roller 7, and the full color transferred to the recording medium 6 is transferred. The toner image is fixed on the recording medium 6 by the fixing device 8 and discharged from the image forming apparatus.

  In the image forming apparatus according to the second embodiment, when the developing roller 31 provided in the developing device 30 is set so as to appropriately face the image carrier 21 provided in the imaging cartridge 20, as described above. A second guide groove 17 is provided in the front plate 11a on the front side and the back side of the transfer unit 10, and a locking projection 32 provided in the developing device 30 is inserted into the second guide groove 17 to thereby develop the developing device. 30 is set at a predetermined position, but the method of setting the developing roller 31 provided in the developing device 30 so as to appropriately face the image carrier 21 provided in the imaging cartridge 20 is particularly the above-described method. It is not limited to such a method. For example, as shown in FIG. 13, a mounting portion 27 for mounting the developing device 30 on the imaging cartridge 20 itself is provided, and a locking groove 28 is formed in the mounting portion 27, and the developing device 30 is formed in the locking groove 28. It is also possible to set the developing device 30 at a predetermined position by inserting the locking protrusion 32 provided on the surface.

  In each of the image forming apparatuses in the first and second embodiments, the imaging cartridge 20 provided with the image carrier 11 and the developing device 30 are provided separately. However, the developing device is an image carrier or the like. It is also possible to use an integrated imaging cartridge.

1 is a schematic front view of a transfer unit used in an image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is an explanatory sectional view of the transfer unit shown in FIG. 1. FIG. 2 is a schematic front view of an imaging cartridge used in the image forming apparatus according to the first embodiment. FIG. 4 is an explanatory cross-sectional view of the imaging cartridge shown in FIG. 3. FIG. 3 is a partial explanatory view showing a state in which an imaging cartridge is mounted on a transfer unit when performing image formation using the image forming apparatus according to the first embodiment. FIG. 2 is a schematic explanatory diagram illustrating a state in which image formation is performed using the image forming apparatus according to the first embodiment. FIG. 5 is a cross-sectional explanatory view illustrating a modification example of an imaging cartridge used in the image forming apparatus according to the first embodiment. FIG. 6 is a cross-sectional explanatory view of a transfer unit used in an image forming apparatus according to Embodiment 2 of the present invention. FIG. 6 is a schematic front view of an imaging cartridge used in the image forming apparatus according to the second embodiment. FIG. 10 is an explanatory cross-sectional view of the imaging cartridge shown in FIG. 9. FIG. 6 is a schematic front view of a developing device used in the image forming apparatus according to the second embodiment. FIG. 10 is a cross-sectional explanatory view showing a state where an imaging cartridge and a developing device are mounted on a transfer unit when performing image formation using the image forming apparatus according to the second embodiment. FIG. 10 is a schematic explanatory diagram of a modification in which the developing device is attached to the imaging cartridge in the image forming apparatus according to the second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 4 Exposure device 5 Paper feed tray 6 Recording medium 7 Secondary transfer roller 8 Fixing device 10 Transfer unit 11 Housing 11a Side plate 12 Rotating roller 13 Intermediate transfer belt 13a Lower belt 13b Upper belt 14 Primary transfer roller 15 Locking portion ( Mounting guide)
16 Guide groove (Mounting guide part)
Reference Signs List 17 Second guide groove 20 Imaging cartridge 20a Top opening 20b Side opening 21 Image carrier 22 Charging roller 22a Scorotron charging device 23 Cleaning brush 23a Cleaning blade 24 Static elimination lamp 25 Engaging portion 26 Protruding portion 27 Mounting portion 28 Engagement Stop groove 30 Developing device 31 Developing roller 32 Locking protrusion

Claims (4)

  A transfer unit provided with at least an endless intermediate transfer belt driven by a rotating roller in a housing, and an imaging cartridge provided with at least an image carrier on which a toner image to be transferred to the intermediate transfer belt is formed In the image forming apparatus provided, a mounting guide portion for mounting the imaging cartridge on the transfer unit is provided so that the image carrier provided on the imaging cartridge faces the intermediate transfer belt provided on the transfer unit. An image forming apparatus.   2. The image forming apparatus according to claim 1, wherein a plurality of mounting guide portions for mounting the imaging cartridge on the transfer unit are provided.   3. The image forming apparatus according to claim 1, wherein a locking portion for locking the imaging cartridge to the housing of the transfer unit is orthogonal to a driving direction of the intermediate transfer belt as a mounting guide portion in the transfer unit. An image forming apparatus characterized in that an engaging portion that is engaged with the engaging portion is formed on the imaging cartridge while being formed along the direction in which the image forming cartridge is formed.   3. The image forming apparatus according to claim 1, wherein a guide groove for guiding the imaging cartridge is formed in a housing of the transfer unit as a mounting guide portion in the transfer unit. An image forming apparatus, comprising: a protrusion inserted into the guide groove.

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