JP2004279919A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color image forming apparatus in which a space inside the image forming apparatus is efficiently utilized to downsize the apparatus by providing a waste toner recovery container in the surplus space generated in the image forming apparatus, and the maintainability is not impaired due to the installation of the waste toner recovery container. <P>SOLUTION: In the color image forming apparatus, toner images formed by plural image forming engines are primarily transferred to an intermediate transfer belt in multiplex, thereafter, the multiplex transferred toner image is secondarily transferred from the intermediate transfer belt to a recording sheet, besides, the recording sheet with the transferred toner image is carried to a fixing unit by a sheet carrying belt. In the apparatus, the waste toner recovery container for recovering the waste toner discharged from cleaners for the image forming engines and the intermediate transfer belt and for storing the toner altogether is provided to be housed in a triangular space formed by the intermediate transfer belt and the sheet carrying means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a color image forming apparatus including a plurality of image forming engines and transferring a toner image formed by the image forming engines to a recording sheet via an intermediate transfer belt, such as a color electrophotographic copying machine or a color laser beam printer. More particularly, the present invention relates to an improvement for saving space of the image forming apparatus.
[0002]
[Prior art]
[Patent Document 1] Japanese Patent Application Laid-Open No. 10-63158
[Patent Document 2] Japanese Patent Application Laid-Open No. 2002-148888
[0003]
In an image forming apparatus such as an electrophotographic copying machine or a laser beam printer, a toner image developed on a photosensitive drum is transferred to a recording sheet, and then residual toner attached to the photosensitive drum is removed by a cleaner. The removed residual toner is collected as waste toner in a collection container in the image forming apparatus. This collection container is a consumable part, and is generally replaced with an empty collection container when the waste toner becomes full.
[0004]
On the other hand, in recent years, a so-called tandem color image is obtained in which a multicolor toner image formed by a plurality of image forming engines is primarily transferred to an intermediate transfer belt, and then a secondary image is transferred from the intermediate transfer belt to a recording sheet to obtain a color image. Image forming apparatuses have also appeared. In the case of this tandem type color image forming apparatus, since there is a photosensitive drum and a drum cleaner for cleaning the photosensitive drum for each of the yellow, cyan, magenta and black image forming engines, the drum cleaners of the four image forming engines are used. It becomes necessary to collect waste toner. After the secondary transfer of the toner image from the intermediate transfer belt to the recording sheet, it is necessary to clean the toner attached to the intermediate transfer belt, and a cleaner is provided for the intermediate transfer belt. ing. Therefore, in the case of a tandem type color image forming apparatus, it is necessary to collect waste toner from at least five cleaners. In recent years, so-called rejection of a deteriorated developer while replenishing a new two-component developer in order to omit the replacement operation of the deteriorated developer in a developing device using a two-component developer composed of a toner and a carrier is omitted. A trickle development system has appeared. Therefore, when this developing method is adopted, it is necessary to collect the deteriorated developer discharged from the developing device of each color.
[0005]
As described above, the waste toner collection box is a consumable item and must be replaced when it is full.Therefore, if a collection box is provided for each cleaner, it takes time and effort to replace it. In addition, since there is a difference in the amount of waste toner collected between the cleaners, the collection box needs to be replaced at various times, which makes the replacement operation very complicated. For this reason, for example, in a color image forming apparatus disclosed in JP-A-10-63158 and JP-A-2002-148883, one collection container having a certain capacity is provided, and a drum cleaner and a belt cleaner are used. The waste toner is conveyed to the collection container, and the waste toner discharged from the cleaner is collectively stored and stored.
[0006]
[Problems to be solved by the invention]
However, in the case of a tandem type color image forming apparatus having a plurality of image forming engines, since the waste toner is discharged from the plurality of cleaners and the developing devices as described above, it is necessary to reduce the frequency of replacing the collecting container. Then, the collecting container for collectively storing the waste toner must have a certain large volume, and there is a problem that the space occupied by the collecting container in the image forming apparatus increases. Therefore, the size of the apparatus itself is increased depending on the location of the collection container in the image forming apparatus.
[0007]
Further, in the color image forming apparatus disclosed in Japanese Patent Application Laid-Open No. 2002-148888, the collection container is provided so as to cover the front side of the image forming apparatus in consideration of the convenience of the replacement operation of the collection container. Actually, since it is provided adjacent to the intermediate transfer belt in the width direction, for example, when replacing the intermediate transfer belt, it is necessary to remove the waste toner collecting container, and the maintenance work of the apparatus is required. It was complicated.
[0008]
SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and an object of the present invention is to provide a waste toner collecting container in a surplus space generated in an image forming apparatus so that the space in the apparatus can be efficiently used. It is another object of the present invention to provide a color image forming apparatus in which the size of the apparatus is reduced and the maintenance performance is not impaired by the installation of the waste toner collecting container.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a color image forming apparatus according to the present invention includes a plurality of image forming engines for forming a toner image corresponding to image information on a photosensitive drum, and a plurality of image forming engines that are wound around a plurality of transport rolls. An intermediate transfer belt on which the toner image is primarily transferred from the image forming engine; a secondary transfer means for secondary-transferring the toner image multiplex-transferred onto the intermediate transfer belt to a recording sheet; A sheet conveying means for conveying the recording sheet peeled off from the intermediate transfer belt, a fixing device for receiving the recording sheet from the sheet conveying means and heating and fixing the toner image to the recording sheet; A belt cleaner for cleaning the surface of the intermediate transfer belt after the transfer, a waste toner discharged from each of the image forming engines and a waste toner discharged from the belt cleaner; A waste toner collecting container for collecting and collectively storing the waste toner, wherein a predetermined peel angle is given between the recording sheet passing through the secondary transfer means and the surface of the intermediate transfer belt. The waste toner collecting container is accommodated in a triangular space sandwiched between the intermediate transfer belt and the sheet conveying means, assuming an image forming apparatus in which a triangular space is formed between the sheet conveying means and the sheet conveying means. It is characterized by the following.
[0010]
In the image forming apparatus configured such that the toner image primarily transferred from the image forming engine to the intermediate transfer belt is secondarily transferred to the recording sheet, the recording sheet that has passed through the secondary transfer unit is surely transferred from the intermediate transfer belt to the intermediate transfer belt. In order to separate the recording sheet after passing through the secondary transfer unit, it is necessary to provide a certain degree of separation angle between the recording sheet after passing through the secondary transfer unit and the surface of the intermediate transfer belt. Inevitably, a triangular space is formed between the sheet conveying means and the intermediate transfer belt opposed thereto. In the present invention, the waste toner collecting container is accommodated in this triangular space sandwiched between the intermediate transfer belt and the sheet conveying means, and the inevitably generated triangular space is effectively used, so that the device in the image forming apparatus can be used. In order to save space.
[0011]
Here, from the viewpoint of reducing the replacement frequency of the waste toner collecting container, it is necessary to be able to collect the waste toner by effectively utilizing the volume of the waste toner collecting container. Preferably, a waste toner receiving port is provided at the uppermost part of the waste toner collecting container, and a bottom portion of the waste toner collecting container immediately below the receiving port is formed on a downward slope toward the secondary transfer means. With this configuration, the waste toner can be filled into every corner of the waste toner collecting container arranged in the triangular space, and the volume of the collecting container can be effectively used.
[0012]
Further, the toner image secondarily transferred to the recording sheet is not yet fixed, and the recording sheet on which the toner image is secondarily transferred is sent to the fixing device via the sheet conveying means. , And must be provided at a position close to the intermediate transfer belt. For this reason, when no device is provided in the triangular space, there is a concern that the heat generated in the fixing device may adversely affect the intermediate transfer belt made of a resin film. Therefore, from such a viewpoint, it is preferable that the waste toner collecting container provided in the triangular space is provided so as to separate the intermediate transfer belt and the fixing device. By disposing the waste toner collecting container in this way, it is possible to positively prevent the heat generated in the fixing device from being conducted to the intermediate transfer belt. Even if the waste toner collecting container is heated by being adjacent to the fixing device, what is contained in the collecting container is the toner to be discarded, and there is no problem.
[0013]
On the other hand, waste toner discharged from each image forming engine and belt cleaner is sent to the receiving port of the waste toner collection container via a transport path such as a pipe or tube. Since they are provided adjacent to each other, it is also possible to integrally form the casing holding the belt cleaner with the waste toner collecting container. With this configuration, it is possible to further save space in the image forming apparatus.
[0014]
Further, from the viewpoint of facilitating replacement of the waste toner collection container and facilitating maintenance of devices adjacent to the waste toner collection container such as an intermediate transfer belt, the waste toner collection container is Along the width direction of the intermediate transfer belt, the intermediate transfer belt is configured to be able to be drawn out of the triangular space between the intermediate transfer belt and the sheet conveying means, and without changing the arrangement positions of the intermediate transfer belt and the sheet conveying means. It is preferable that they can be exchanged independently. With such a configuration, by pulling out the waste toner collecting container from the triangular space, the waste toner collecting container can be easily replaced without touching the adjacent intermediate transfer belt or sheet conveying means, Further, even when the maintenance of the intermediate transfer belt and the sheet conveying means is performed, it is not necessary to touch the waste toner collecting container housed in the triangular space at all, and the maintenance operation can be easily performed. .
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the color image forming apparatus of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic diagram showing a configuration of a color laser beam printer to which the present invention is applied. This laser beam printer includes four image forming engines 10Y, 10M, 10C, and 10Bk that form toner images for each of the colors of yellow, magenta, cyan, and black, and the toner images are primarily transferred from each image forming engine. The image forming apparatus includes an intermediate transfer belt 20, and is configured to secondarily transfer a toner image multiplex-transferred onto the intermediate transfer belt 20 to a recording sheet P to form a full-color image.
[0016]
The intermediate transfer belt 20 is formed in an endless shape and is wrapped around three belt transport rolls 21 to 23 including a drive roll 21. Each of the color image forming engines 10Y, 10M, It is configured to receive the primary transfer of the toner image formed at 10C and 10Bk. Further, a secondary transfer roll 30 is disposed at a position facing the belt transport roll 23 with the intermediate transfer belt 20 interposed therebetween, and the recording sheet P is placed between the transfer roll 30 and the intermediate transfer belt 20 that are pressed against each other. The intermediate transfer belt 20 is inserted to receive the secondary transfer of the toner image from the intermediate transfer belt 20. That is, the belt transport roll 23 functions as a backup roll of the transfer roll 30, and the transfer roll 30 and the belt transport roll 23 constitute a secondary transfer unit.
[0017]
The intermediate transfer belt 20 is stretched around three belt transport rolls 21 to 23, and a substantially horizontal image receiving span is formed between the belt transport rolls 21 and 22. A third belt transport roll 23 facing the next transfer roll 30 is provided, and is stretched in an inverted triangular shape as a whole.
[0018]
On the image receiving span of the intermediate transfer belt 20, the above-described four image forming engines 10Y, 10M, 10C, and 10Bk are arranged in parallel, and the toner images formed in accordance with the image information of each color are intermediately transferred. The primary transfer is performed on the belt 20. These four image forming engines are arranged in the order of yellow 10Y, magenta 10M, cyan 10C, and black 10Bk along the rotation direction of the intermediate transfer belt 20, and form the black image which will be used most frequently. The image engine 10Bk is arranged closest to the secondary transfer section. Each of the image forming engines 10Y, 10M, 10C, and 10Bk includes a raster scanning unit 12 that exposes the photosensitive drum 11 included in each image forming engine in accordance with image information. The laser light Bm modulated accordingly exposes the photosensitive drums 11 of the image forming engines 10Y, 10M, 10C and 10Bk.
[0019]
Each of the image forming engines 10Y, 10M, 10C, and 10Bk includes a photosensitive drum 11, a charger 13 that charges the photosensitive drum 11 to a uniform background potential, and a photosensitive drum that is exposed by the laser beam Bm. A developing unit 14 for developing the electrostatic latent image formed on the body drum 11 to form a toner image, and residual toner and paper dust from the surface of the photosensitive drum 11 after transferring the toner image to the intermediate transfer belt 20. And a pre-cleaning charge remover 16 that removes residual toner prior to cleaning by the drum cleaner, and forms a toner image on the photosensitive drum 11 in accordance with image information of each color. Is configured to obtain.
[0020]
The developing device 14 is of a type using a two-component developer in which a toner and a carrier are mixed. In order to omit maintenance of replacement of the developer due to aging, the toner and the carrier are not supplied from a replenishment cartridge (not shown). A so-called trickle developing method is used in which the mixed developer is supplied and the deteriorated developer is automatically discharged. The residual toner removed by each drum cleaner 15 is discharged as waste toner by an auger (not shown). The deteriorated developer discharged from each developing device 14 and the waste toner discharged from the drum cleaner 15 are transported to the collecting container 1 described below via the transport pipe 2 provided along the image receiving span of the intermediate transfer belt 20. It is configured to be dropped into the collection container 1.
[0021]
Primary transfer rolls 17Y, 17M, 17C, and 17Bk are arranged at positions facing the photosensitive drums 11 of the image forming engines 10Y, 10M, 10C, and 10Bk so as to sandwich the intermediate transfer belt 20. By applying a predetermined transfer bias voltage to the photosensitive drums 17Y, 17M, 17C, and 17Bk, an electric field is formed between the photosensitive drum 11 and the transfer rolls 17Y, 17M, 17C, and 17Bk. The charged toner image is transferred to the intermediate transfer belt 20 by Coulomb force.
[0022]
Therefore, in forming a full-color image by the color laser beam printer, first, the raster scanning unit 12 causes the photosensitive drums 11 of the image forming engines 10Y, 10M, 10C, and 10Bk to move at predetermined timing in accordance with the image information of each color. Exposure is performed, whereby a toner image corresponding to image information is formed on the photosensitive drum 11 of each of the image forming engines 10Y, 10M, 10C, and 10Bk. The toner images formed by the respective image forming engines 10Y, 10M, 10C, and 10Bk are sequentially transferred to the rotating intermediate transfer belt 20, and on the intermediate transfer belt 20, a multi-toner image in which the toner images of the respective colors overlap is formed. It is formed.
[0023]
On the other hand, after the recording sheet P is pulled out one by one from the paper feed cassette 40 by the paper feed roll 41, the intermediate transfer belt 20 and the secondary transfer roll 30 pass through a predetermined sheet feed path 46 shown by a broken line in the drawing. Is fed to the secondary transfer section in contact with. A registration roll 42 is provided in front of the secondary transfer unit. The entry timing of the recording sheet P into the secondary transfer unit is controlled by the registration roll 42, and the recording sheet P is primarily transferred onto the intermediate transfer belt 20. Alignment with the toner image is performed.
[0024]
The backup roll 23 facing the secondary transfer roll 30 with the intermediate transfer belt 20 interposed therebetween is formed by covering the surface of an insulating roll with a semiconductive sheet, and a predetermined transfer bias voltage is applied to the surface. Conductive contact roll 50 is in contact therewith. Accordingly, when a transfer bias voltage having the same polarity as that of the toner image is applied to the contact roll 50 and a charge is applied to the surface of the backup roll 23, the transfer roll 30 located on the back side of the recording sheet P and the intermediate transfer A transfer electric field is formed between the intermediate transfer belt 20 and the backup roll 23 located on the back side of the belt 20, and the toner image held on the intermediate transfer belt 20 is electrostatically transferred to the recording sheet P.
[0025]
After the recording sheet P on which the secondary transfer of the toner image has been performed is separated from the intermediate transfer belt 20, the recording sheet P is conveyed to a fixing device 44 by two sheet conveying belts 43 arranged in series. As shown in FIG. 2, a static elimination member 60 is provided downstream of the secondary transfer roll 30 along the transport direction of the recording sheet P, and a sheet guide plate 61 is provided so as to be continuous with the static elimination member 60. The recording sheet P peeled off from the intermediate transfer belt 20 passes over the charge removing member 60 and the sheet guide plate 61 and reaches the sheet conveying belt 43. In order to separate the recording sheet P from the intermediate transfer belt 20 and prevent the separated recording sheet P from re-adhering to the intermediate transfer belt 20, the intermediate transfer belt 20 and the recording sheet P after passing through the secondary transfer unit are separated. A certain degree of separation angle α is given between the sheet P and the conveyance path of P, and a triangular space is formed between the sheet conveyance belt 43 and the intermediate transfer belt 20 opposed thereto. I have.
[0026]
After the toner image is fixed on the recording sheet P by the fixing device 44, the recording sheet P is discharged to the discharge tray 45, whereby the formation of the full-color image on the recording sheet P is completed. Further, in this printer, in order to enable a so-called face-down discharge in which the image surface of the recording sheet P faces downward, an inverter passage 47 for inverting the front and back of the recording sheet P is provided between the fixing device 44 and the discharge tray 45. Is formed. Further, the inverter passage 47 is connected to the above-described sheet feeding passage 46 by a sheet re-sending passage 48, and the recording sheet P turned upside down in the inverter passage 47 is again sent to the secondary transfer portion, so that the recording sheet P It is possible to form a recorded image on both sides.
[0027]
Further, the surface area of the intermediate transfer belt 20 after the secondary transfer of the toner image to the recording sheet P is cleaned by the belt cleaner 26, and then the image receiving span in which the image forming engines 10Y, 10M, 10C, and 10Bk are arranged again. The next toner image is primarily transferred to these surface areas by these image forming engines. The belt cleaner 26 is provided on the front side of the belt transport roll 21 with respect to the rotation direction of the intermediate transfer belt 20 and includes a cleaning blade that slides on the surface of the intermediate transfer belt 20. The transfer residual toner, paper dust, and the like are scraped off from the surface of the device, and are dropped into a waste toner collecting container 1 described later.
[0028]
The color laser beam printer of this embodiment thus configured is a so-called tandem type provided with four image forming engines 10Y, 10M, 10C, and 10Bk. Each image forming engine includes a developing unit 14 and a drum cleaner 15. Therefore, the total amount of the deteriorated developer discharged from each of the developing devices 14 and the total amount of the waste toner discharged from each of the drum cleaners 15 are large, and the collection container for storing the deteriorated developer and the waste toner is large. Is needed. Further, the printer of the present embodiment is also provided with a belt cleaner 26 for cleaning the intermediate transfer belt 20, and also requires a collection container for storing the waste toner discharged from the belt cleaner 26. The container for collecting the waste toner discharged from the belt cleaner 26 can be the same as the container for collecting the waste toner and the like discharged from each image forming engine. In this case, the frequency of replacing the collection container is reduced. In view of this, a larger collection container is required. However, the location of such a large collection container in the printer housing poses a problem, and depending on the installation location, the size of the printer housing may be increased.
[0029]
Therefore, in the color laser beam printer of the present embodiment, the waste toner collecting container 1 is provided in a triangular space formed between the sheet conveying belt 43 and the intermediate transfer belt 20, and the image forming engines 10Y, All of the deteriorated developer and waste toner conveyed from the 10M, 10C, and 10Bk developing units 14 and the drum cleaner 15 and the waste toner discharged from the belt cleaner 26 are collectively dropped into the toner collection container 1. It is composed.
[0030]
In order to reliably separate the recording sheet P that has passed through the secondary transfer portion from the intermediate transfer belt 20, the recording sheet P is located between the conveyance path of the recording sheet P located downstream of the secondary transfer portion and the surface of the intermediate transfer belt 20. Is provided with a predetermined peeling angle α, and a triangular space tends to be unavoidably formed between the sheet conveying belt 43 and the intermediate transfer belt 20 opposed thereto. Therefore, if the waste toner collecting container 1 is accommodated in this triangular space, the excess space in the printer housing is effectively used, and the large collecting container 1 can be provided without increasing the size of the printer housing. It becomes possible.
[0031]
On the other hand, since the fixing device 44 that generates a large amount of heat energy is disposed downstream of the sheet conveying belt 43, the heat energy generated by the fixing device 44 is It is important to design so as not to transmit to the image forming engines 10Y, 10M, 10C and 10Bk. For this reason, conventionally, measures such as forming an air flow around the fixing device 44 for discharging the high-temperature atmosphere to the outside of the printer housing are required, and the layout of each device in the printer housing is complicated. I was doing it. However, when the waste toner collecting container 1 is provided in the triangular space, the collecting container 1 can be provided so as to shield the intermediate transfer belt 20 from the fixing device 44. It is possible to effectively prevent the heat energy of the fixing device 44 from being transmitted to the intermediate transfer belt 20 and the image forming engines 10Y, 10M, 10C, and 10Bk. Further, even if the collection container 1 is used as a heat insulating material, the collection container 1 only contains waste toner and deteriorated developer, so that there is no problem even if the contents are deteriorated by high temperature. Never.
[0032]
The collection container 1 is provided with two waste toner receiving ports 3 at the top of the collection container 1, one of which carries the deteriorated developer and the waste toner from each of the image forming engines 10Y, 10M, 10C, and 10K. One end of the transfer pipe 2 is connected. The other receiving port 3 is connected to a belt cleaner 26, so that the waste toner scraped off from the intermediate transfer belt 20 is dropped into the collection container 1. In order to allow the waste toner and the like dropped into the collection container 1 from the receiving port 3 to slide down by its own weight to the deepest part of the collection container 1, specifically, to an acute end near the secondary transfer portion, The bottom portion 4 of the collection container immediately below these receiving ports 3 is formed on a downwardly inclined surface that becomes deeper as approaching the secondary transfer portion. Is effectively used, and the filling rate of the waste toner and the deteriorated developer into the collection container 1 can be increased.
[0033]
Further, a rail (not shown) extending along the width direction of the intermediate transfer belt 20 is provided in the printer housing, and a sliding member (not shown) which engages with the rail is provided outside the collection container 1. Zu) is fixed. As a result, the collection container 1 can be freely pulled out from the triangular space between the sheet conveying belt 43 and the intermediate transfer belt 20 along the width direction of the intermediate transfer belt 20. Is configured to be easily performed. Further, since the collection container 1 is accommodated in a triangular space formed between the intermediate transfer belt 20 and the sheet conveyance belt 43, the collection container 1 is placed in the width direction of the intermediate transfer belt 20. The waste toner collecting container 1 is independently pulled out to the front side (front side in the drawing) of the printer housing without touching these devices without interfering with the sheet feeding belt 20 or the sheet conveying belt 43, and the replacement operation is performed. It is possible to easily perform such replacement work of the collection container 1.
[0034]
As described above, according to the color laser beam printer of the present embodiment, the color laser beam printer is formed between the sheet conveying means 43 for conveying the recording sheet P after passing through the secondary transfer section and the surface of the intermediate transfer belt 20 facing the sheet conveying means 43. A waste toner collecting container 1 is provided in the triangular space using the triangular space, and the toner is discharged from the drum cleaners 15 of the image forming engines 10Y, 10M, 10C, and 10Bk, the developing device 14, and the belt cleaner 26. Since the waste toner and the deteriorated developer are configured to be collectively stored in the collection container 1, the large-capacity collection container 1 can be stored in the printer housing without having to secure a space for installing the collection container 1 in the printer housing. The printer can be housed in the body, and the size of the printer housing itself can be reduced.
[0035]
FIG. 3 shows a second embodiment of a color laser beam printer to which the present invention is applied. In this embodiment, the housing of the belt cleaner 26 is formed integrally with the waste toner collecting container 1, and the waste toner scraped off from the surface of the intermediate transfer belt 20 by the cleaning blade of the belt cleaner 26 is placed in the collecting container 1. It was configured to collect directly. Therefore, by replacing the collection container 1, the belt cleaner 26 is also replaced, and the cleaning blade, which is worn or sagged due to use over time, is replaced with a new cleaning blade together with the collection container 1 in one replacement operation. It becomes possible to exchange. The other configuration is the same as that of the first embodiment, and the detailed description is omitted.
[0036]
【The invention's effect】
As described above, according to the color image forming apparatus of the present invention, the waste toner collecting container is accommodated in the triangular space sandwiched between the intermediate transfer belt and the sheet conveying means, and the above-described problem has occurred. By effectively utilizing the triangular space, it is possible to efficiently use the space in the device and to reduce the size of the device. Further, since the waste toner collecting container provided in the triangular space does not interfere with the intermediate transfer belt in the width direction at all, the installation of the waste toner collecting container enables the peripheral toner such as the intermediate transfer belt to be installed. The maintainability is not impaired at all.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a first embodiment of a color laser beam printer to which the present invention is applied.
FIG. 2 is an enlarged view showing the vicinity of a secondary transfer portion of the printer according to the embodiment.
FIG. 3 is a schematic configuration diagram showing a second embodiment of a color laser beam printer to which the present invention is applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Collection container, 10Y, 10M, 10C, 10Bk ... Image forming engine, 14 ... Developing device, 15 ... Drum cleaner, 20 ... Intermediate transfer belt, 26 ... Belt cleaner, 30 ... Secondary transfer roll, 43 ... Sheet conveyance belt , 44 ... Fusing unit

Claims (6)

A plurality of image forming engines for forming toner images corresponding to the image information on the photosensitive drums, an intermediate transfer belt which is wound around a plurality of transport rolls and to which the toner image is primarily transferred from each image forming engine; Secondary transfer means for secondary-transferring the toner images multiplex-transferred onto the intermediate transfer belt to a recording sheet, and sheet conveying means for conveying the recording sheet peeled off from the intermediate transfer belt through the secondary transfer means And a fixing device that receives the recording sheet from the sheet conveying means and heat-fixes the toner image to the recording sheet, and a belt cleaner that cleans the surface of the intermediate transfer belt that has completed the secondary transfer of the toner image. A waste toner collection container that collects and collectively stores waste toner discharged from each of the image forming engines and waste toner discharged from the belt cleaner,
A predetermined peel angle is provided between the recording sheet that has passed through the secondary transfer unit and the surface of the intermediate transfer belt, and a triangular space is formed between the intermediate transfer belt and the sheet conveying unit that faces the intermediate transfer belt. In the formed image forming apparatus,
A color image forming apparatus, wherein the waste toner collecting container is accommodated in a triangular space sandwiched between the intermediate transfer belt and sheet conveying means. The waste toner collecting container is provided with a waste toner receiving port at the uppermost portion thereof, and a bottom portion of the waste toner collecting container immediately below the receiving port is formed on a downward slope toward the secondary transfer means. The color image forming apparatus according to claim 1. 2. The color image forming apparatus according to claim 1, wherein the waste toner collecting container is provided at a position separating the intermediate transfer belt and a fixing device. 2. The color image forming apparatus according to claim 1, wherein the housing holding the belt cleaner is provided integrally with a waste toner collecting container. The image forming engine includes a developing device for developing the electrostatic latent image formed on the photosensitive drum with toner, and a drum cleaner for cleaning the surface of the photosensitive drum after the primary transfer of the toner image. 2. The color image forming apparatus according to claim 1, wherein the deteriorated developer and the collected toner in the drum cleaner are discharged as waste toner to the waste toner collecting container. The waste toner collecting container is configured to be able to be drawn out of the triangular space between the intermediate transfer belt and the sheet conveying means along the width direction of the intermediate transfer belt, and to dispose the arrangement position of the intermediate transfer belt and the sheet conveying means. 2. The color image forming apparatus according to claim 1, wherein the color image forming apparatus can be exchanged independently without being changed.

Images