JP2007271855A - Cleaning device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning device which separates an agent in waste toner and detects an agent leak in its early stage, and also to provide an image forming apparatus having the cleaning device. <P>SOLUTION: The cleaning device 19 is provided with a cleaning means 19a of scraping toner off an image carrier 40, and a toner conveying means 71 of conveying the scraped waste toner to a waste toner storage section 78, and a reservoir section 78 with a magnet 75 is provided to a portion of the toner conveying means 71. The image forming apparatus 100 having the cleaning device 19 is also provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cleaning device in an image forming apparatus such as a copying machine, a FAX, or a printer, and an image forming apparatus having the cleaning device.

Conventionally, in electrophotographic image formation, a latent image is formed by an electrostatic charge on an image carrier such as a photoconductive material, and charged toner particles are attached to the electrostatic latent image to form a visible image. Forming. The visible image formed by the toner is finally transferred to a transfer medium such as paper, and then fixed to the transfer medium by heat, pressure, solvent gas, or the like, and becomes an output image.
These image forming methods include a so-called two-component development method in which toner particles and carrier particles are agitated and mixed by a method of charging toner particles for visualization, and carrier particles are not used. In other words, the toner particles are roughly classified into so-called one-component development systems in which charge is applied to toner particles. The one-component development method is classified into a magnetic one-component development method and a non-magnetic one-component development method depending on whether or not a magnetic force is used to hold toner particles on the developing roller.
Up to now, in copiers that require high speed and image reproducibility, and multi-function machines based on this, two components are required due to the demands for toner particle charging stability, start-up stability, and long-term image quality stability. Many development methods have been adopted.
However, in the two-component development method, the agent often leaks from the developing device or is discharged together with the toner during development and adheres to the photosensitive member, and is discharged by being mixed with waste toner by the photosensitive member cleaning device. was there. Therefore, when the agent leakage or outflow occurs, not only the photoreceptor is damaged, but also the intermediate transfer belt and the secondary transfer roller which are downstream units are damaged. In addition to causing image quality degradation and abnormal images, the machine will continue to be used while maintaining some sort of machine failure or abnormality. May not be possible, which has been a problem.
In addition, it is necessary for the machine to stop immediately because of an abnormal operation of the machine. However, there is a problem that the service man call is only made when the image output by the user is recognized as an abnormal image. It was.

Patent Document 1 discloses at least a photoconductor, a charger, a developing device, a transfer device for transferring a toner image, and a cleaning device for removing transfer residual toner on the photoconductor for an image forming apparatus. A process cartridge for an image forming apparatus is disclosed in which the cleaning device has a plurality of paths for transporting removed toner. Thus, when performing toner recycling, it is possible to reduce the number of defective images by conveying the toner to be recycled and the toner not to be recycled for different purposes. However, this method can provide a good supply of recycled toner, but it is not sufficient for detection of agent leakage in waste toner.
In Patent Document 2, a cleaning device that collects resin toner remaining on a photoreceptor after transfer to a recording medium as waste toner and stores it in a waste toner storage portion is stored in the waste toner storage portion. Also disclosed is a cleaning device comprising a toner coagulation means for coagulating the waste toner. However, this makes it possible to obtain a recyclable cleaning device that can easily remove the waste toner, but it is not sufficient for detection of agent leakage in the waste toner.

JP 2003-173118 A JP 2000-29363 A

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a cleaning apparatus and an image forming apparatus for separating an agent in waste toner and detecting an agent leakage at an early stage. .

The features of the present invention, which is a means for solving the above problems, are listed below.
The present invention provides a cleaning device including a cleaning unit that scrapes off toner from an image carrier, and a waste toner transport unit that transports scraped waste toner to a waste toner storage unit. It is a cleaning device provided with a storage part provided with a magnet. Here, the storage unit is preferably configured as a separate component from the waste toner transport unit, but may be a part of the waste toner transport unit.
The present invention is characterized in that the storage unit is provided above the waste toner conveying means.
The present invention is characterized in that a sensor is provided in the storage section.
The present invention includes an apparatus for forming an electrostatic latent image for each color on an image carrier, a two-component developing device for converting the electrostatic latent image into a toner image for each color, and a toner image formed on the image carrier. A device that transfers an image to an intermediate image carrier, and a toner image formed on the image carrier is transferred by applying an arbitrary bias to the transfer paper conveyed from the paper feeding device from the transfer device. An image forming apparatus comprising: a paper transfer device that forms an image on paper; and a fixing device that fixes a toner image on the transfer paper downstream. The image forming device includes the cleaning device described above. .

  According to the present invention, it has become possible to provide a cleaning device and an image forming apparatus for separating an agent in waste toner and detecting an agent leakage at an early stage by the means for solving the problem.

  The best mode for carrying out the present invention will be described below with reference to the drawings. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode of the present invention, and does not limit the scope of the claims.

An example of an embodiment of a tandem color image forming apparatus of the present invention will be described with reference to FIG. In the figure, reference numeral 100 is a copying apparatus main body, 200 is a paper feed table on which the copying apparatus is placed, 300 is a scanner mounted on the copying apparatus main body 100, and 400 is an automatic document feeder (ADF) mounted thereon. The copying machine main body 100 is provided with an endless belt-shaped intermediate transfer member 10 at the center. As shown in FIG. 1, in the illustrated example, it is wound around three support rollers 14, 15, 16 and can be rotated and conveyed clockwise in the figure.
In this illustrated example, an intermediate transfer body cleaning device 17 that removes residual toner remaining on the intermediate transfer body 10 after image transfer is provided to the left of the second support roller 15 among the three. Among the three images, four images of yellow, cyan, magenta, and black are formed on the intermediate transfer member 10 stretched between the first support roller 14 and the second support roller 15 along the conveyance direction. The tandem image forming apparatus 20 is configured by arranging the forming units 18 side by side.
An exposure device 21 is further provided on the tandem image forming apparatus 20 as shown in FIG. On the other hand, a secondary transfer device 22 is provided on the side opposite to the tandem image forming apparatus 20 with the intermediate transfer body 10 interposed therebetween. In the illustrated example, the secondary transfer device 22 is configured by spanning a secondary transfer belt 24, which is an endless belt, between two rollers 23, and is pressed against the third support roller 16 via the intermediate transfer body 10. The image on the intermediate transfer body 10 is transferred to a sheet.
A fixing device 25 for fixing the transferred image on the sheet is provided beside the secondary transfer device 22. The fixing device 25 is configured by pressing a pressure roller 27 against a fixing belt 26 that is an endless belt.
The secondary transfer device 22 described above is also provided with a sheet transport function for transporting the image-transferred sheet to the fixing device 25. Of course, a transfer roller or a non-contact charger may be arranged as the secondary transfer device 22, and in such a case, it is difficult to provide this sheet conveyance function together.
In the illustrated example, a sheet reversing device 28 for reversing the sheet so as to record images on both sides of the sheet is provided below the secondary transfer device 22 and the fixing device 25 in parallel with the tandem image forming device 20 described above. Is provided.

When making a copy using this color electrophotographic apparatus, the original is set on the original table 30 of the automatic original conveying apparatus 400. Alternatively, the automatic document feeder 400 is opened, a document is set on the contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed and pressed by it.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the other contact glass 32. At that time, the scanner 300 is immediately driven to travel the first traveling body 33 and the second traveling body 34. Then, the first traveling body 33 emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body 34, and is reflected by the mirror of the second traveling body 34 and passes through the imaging lens 35. The document is placed in the reading sensor 36 and the original content is read.
When a start switch (not shown) is pressed, one of the support rollers 14, 15 and 16 is rotationally driven by a drive motor (not shown), the other two support rollers are driven to rotate, and the intermediate transfer body 10 is rotated and conveyed. To do. At the same time, the individual image forming means 20 rotates the photoconductor 40 to form monochrome images of black, yellow, magenta, and cyan on each photoconductor 40, respectively. Then, along with the conveyance of the intermediate transfer member 10, the single color images are sequentially transferred to form a composite color image on the intermediate transfer member 10.

On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers 42 of the paper feed table 200 is selectively rotated, and the sheet is fed out from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43, and the separation roller 45. Then, the sheets are separated one by one into the paper feed path 46, transported by the transport roller 47, guided to the paper feed path 48 in the copying machine main body 100, and abutted against the registration roller 49 and stopped.
Alternatively, the sheet feed roller 50 is rotated to feed out the sheets on the manual feed tray 51, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped.
Then, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer body 10, the sheet is fed between the intermediate transfer body 10 and the secondary transfer device 22, and transferred by the secondary transfer device 22. A color image is recorded on the sheet.
The image-transferred sheet is conveyed by the secondary transfer device 22 and sent to the fixing device 25. The fixing device 25 applies heat and pressure to fix the transferred image. Are discharged and stacked on the discharge tray 57. Alternatively, it is switched by the switching claw 55 and put into the sheet reversing device 28, where it is reversed and guided again to the transfer position, and the image is recorded also on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56.
On the other hand, the intermediate transfer body 10 after the image transfer is removed by the intermediate transfer body cleaning device 17 to remove residual toner remaining on the intermediate transfer body 10 after the image transfer, so that the tandem image forming apparatus 20 can prepare for another image formation.
Here, the registration roller 49 is generally used while being grounded, but it is also possible to apply a bias for removing paper dust from the sheet.

  FIG. 2 is a diagram illustrating the cleaning device. In addition to the toner T that has not been transferred to the cleaning portion of the photoconductor 40 shown in the cleaning device 19, it leaks from the developing device, the photoconductor charging unit does not operate, only the developing device operates, and vice versa. If the machine is abnormal, such as when a condition occurs, the agent flows out and is scraped off by the cleaning device 19. The spilled agent includes a carrier.

  FIG. 3 shows the flow of waste toner. The cleaned toner is sent out from the waste toner discharge port 70 to the waste toner container 73. At this time, waste toner conveying means 71 for collecting in the waste toner containing portion 73 is installed, and the waste toner sent from the PCU 74 is conveyed through the waste toner conveying means 71 by the screw 71a. If it is found that the waste toner in the waste toner conveying means 71 is mixed with the agent, the machine can be stopped at an early stage.

FIG. 4 is a view showing the storage section 78 of the present invention. As shown in FIG. 4, a small storage portion 78 is provided above a part of the waste toner conveying means 71, and a magnet 75 is disposed on the top surface of the storage portion 78. If the agent has leaked, the agent is attracted to the magnet 72 and enters the reservoir 78.
At this time, by providing an agent detection sensor 76 such as a transmission type sensor on the side surface of the storage unit 78, it is possible to detect the agent leakage at an early stage and to stop the machine. As a result, it is possible to detect in a short time that the agent has been discharged, so that damage to the image forming apparatus 100 can be reduced.

It is a figure which shows an example of embodiment of the tandem type | mold color image forming apparatus of this invention. It is a figure which shows a cleaning apparatus. FIG. 6 is a diagram illustrating a flow of waste toner. It is a figure which shows the storage part of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Intermediate transfer body 14 Support roller 15 Support roller 16 Support roller 17 Intermediate transfer body cleaning device 18 Image forming means 19 Cleaning device 19a Cleaning blade 20 Tandem image forming device 21 Exposure device 22 Secondary transfer device 23 Roller 24 Secondary transfer belt 25 Fixing device 26 Fixing belt 27 Pressure roller 28 Sheet reversing device 30 Document table 32 Contact glass 33 First traveling member 34 Second traveling member 35 Imaging lens 36 Reading sensor 40 Photosensitive member (image carrier)
42 paper feed roller 43 paper bank 44 paper feed cassette 45 separation roller 46 paper feed path 47 transport roller 48 paper feed path 49 registration roller 50 paper feed roller 51 manual tray 52 separation roller 53 manual paper feed path 55 switching claw 56 discharge roller 57 Paper discharge tray 70 Waste toner discharge port 71 Waste toner conveying means 71a Screw 72 Waste toner flow 73 Waste toner container 74 PCU
75 Magnet 76 Agent detection sensor 77 Leaked agent 78 Storage unit 100 Image forming apparatus (copying apparatus main body)
200 Paper feed table 300 Scanner 400 Automatic document feeder (ADF)
T Toner

Claims (4)

Cleaning means for scraping off the toner from the image carrier;
In a cleaning device comprising waste toner transporting means for transporting scraped waste toner to a waste toner container,
The cleaning apparatus according to claim 1, wherein a storage unit including a magnet is provided in a part of the waste toner conveying unit. The cleaning device according to claim 1,
In the cleaning apparatus, the storage unit is provided above the waste toner conveying unit. The cleaning device according to claim 1 or 2,
The cleaning device, wherein the storage unit includes a sensor. An apparatus for creating an electrostatic latent image for each color on an image carrier;
A two-component developer for converting the electrostatic latent image into a toner image for each color;
An apparatus for transferring an image formed on the image carrier to an intermediate image carrier;
A paper transfer device that forms an image on the transfer paper by transferring the toner image formed on the image carrier onto the transfer paper conveyed from the paper supply device by applying an arbitrary bias from the transfer device;
Further, in an image forming apparatus comprising a fixing device for fixing a toner image on a transfer paper downstream.
An image forming apparatus comprising the cleaning device according to claim 1.

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