JP2005308994A - Cleaning apparatus, transfer apparatus and image forming apparatus equipped with the cleaning apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a failure caused by such a failure that paper powder is held in a cleaning member by removing the paper powder before the paper powder on a secondary transfer material reaches the cleaning member. <P>SOLUTION: The apparatus is provided with an endless intermediate transfer belt 10 transported with rotation while being trained about a plurality of rollers, and a secondary transfer body 74 for transferring the toner image transferred to the belt 10 to a transfer material P in a mass and transporting the material P, and in the apparatus, a cleaning member 71 coming in contact with the surface of the secondary transfer body 74 is arranged, and also, a roller type brush member 73 is freely rotatably arranged in contact with the surface of the secondary transfer body 74 on the upstream side of the cleaning member 71 in the rotating direction of the secondary transfer body 74, and the bite quantity A of the brush member 73 into the secondary transfer body 74 is controlled to be ≥1 mm. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cleaning device that removes toner, paper dust, and the like adhering to a secondary transfer member, and a transfer device and an image forming apparatus having the cleaning device.

In general, the secondary transfer member that transfers the toner image transferred to the intermediate transfer member to the transfer material in a batch is in contact with the intermediate transfer member, so that the transfer material such as transfer paper is not placed on the portion or between the sheets. Then, the background dirt toner and the process pattern on the intermediate transfer member are transferred and the surface thereof becomes dirty. For this reason, a cleaning member such as a cleaning blade is brought into contact with the surface of the secondary transfer member to clean the attached toner, and the toner is scraped off. As described above, normally, the toner is removed by the cleaning member, so that no trouble occurs in the transfer and separation processes.
In Patent Document 1, a cleaning member that contacts the surface of a transfer conveyance belt serving as a transfer member, and a paper member on the transfer conveyance belt that is disposed on the upstream side of the cleaning member and contacts the surface of the transfer conveyance belt are removed. A cleaning device is described.

JP-A-9-160399

  In the removal of foreign matter by the cleaning member, paper dust may be squeezed between the cleaning member and a member (secondary transfer member) that contacts the cleaning member, resulting in a toner cleaning failure. Such a phenomenon occurs particularly when the cleaning member is a blade member that is in sliding contact with the secondary transfer member. As a cause of the generation of paper dust, in recent years, recycled paper is used as a transfer material in consideration of the environment and the like, but there are increasing opportunities. In the case of recycled paper, the amount of paper dust generated is larger than so-called high-quality paper and plain paper. Normally, paper dust should be scraped off by the cleaning member in the same manner as the toner. However, since the paper dust is fibrous, it often gets caught between the secondary transfer member and the cleaning member. A gap is formed between the next transfer member and the cleaning member, and the toner slips through. Further, when the paper dust is collected, the toner stays in that portion, and there is a situation where cleaning cannot be performed.

  In such a state, since the toner remains on the secondary transfer member, the toner is transferred to the back of the transfer material in the next transfer process, causing back contamination. Further, if toner remains on the secondary transfer body, the toner is interposed between the secondary transfer body and the transfer material, so that the adsorption force between the two is reduced, and the transfer material from the intermediate transfer body is removed. Separation failure is likely to occur. When the state where the paper dust is stagnated continues, the secondary transfer body is rubbed with toner, and the toner adheres to the secondary transfer body and causes filming. In this filling state, even if paper dust is removed, it becomes difficult to clean the toner, resulting in backside contamination and poor separation, and the secondary transfer member must be replaced.

  As a method for removing paper dust, there is a method in which the secondary transfer member is reversed at regular intervals and the paper dust is shifted and dropped. However, in the case of an image forming apparatus that performs an image forming operation at high speed, cleaning is performed during continuous copying. There is no time to put in the reverse rotation of the paper, and paper dust is collected. In addition, the continuous copying increases the temperature in the apparatus and easily causes toner filming.

  In the cleaning device described in Patent Document 1, it is described that paper dust is removed by a brush member disposed upstream of the cleaning member, but the amount of biting of the brush member with respect to the object to be cleaned is not defined. In addition, when acrylic resin is used as the material of the brush member, the outer diameter of the brush is reduced over time, and the amount of brush biting into the object to be contacted is reduced, so that the paper dust removal effect is reduced and the cleaning member is reduced. And paper dust is sandwiched between the contact object and the contact object.

  The present invention has been made in view of the above circumstances, and is caused by removing paper dust before the paper dust on the secondary transfer body reaches the cleaning member and swallowing the paper dust into the cleaning member. It is an object of the present invention to provide a cleaning device that can prevent the above, a transfer device including the same, and an image forming apparatus.

  In order to achieve the above-mentioned target, a cleaning device for cleaning the surface of a secondary transfer body that transfers the toner image transferred to the intermediate transfer body according to the present invention to a transfer material and conveys it onto the surface of the secondary transfer body. A secondary transfer body having a cleaning member in contact with and a roller-like brush member rotatably disposed upstream of the cleaning member in the transport direction of the secondary transfer body and in contact with the surface of the secondary transfer body The amount of biting of the brush member with respect to is set to 1 mm or more.

  An endless intermediate transfer member that is stretched and rotated by a plurality of rollers and transferred by an image forming unit according to the present invention, and a toner image transferred to the intermediate transfer member are used as a transfer material. A transfer device having a secondary transfer body that is transferred in a batch and transported has a cleaning device having the above characteristics as a cleaning device that cleans the surface of the secondary transfer body.

  An endless intermediate transfer member stretched around a plurality of rollers and rotated and conveyed, an image forming unit arranged along the intermediate transfer member to form a toner image, and the image transferred to the intermediate transfer member An image forming apparatus having a secondary transfer body that collectively transfers a toner image onto a transfer material and conveys the toner image has the cleaning device as a cleaning device that cleans the surface of the secondary transfer body.

  When the paper dust removed from the secondary transfer member by the brush member accumulates on the brush member, it returns to the secondary transfer member and is sandwiched between the cleaning member in the same manner as when there is no brush member. Providing the flicker member so as to come into contact is preferable in that the paper powder adhering to the brush member by scraping from the secondary transfer member can be removed.

  If the material of the brush member is made of polyester resin, the amount of change in the outer diameter of the brush member over time is reduced compared with the case of acrylic resin, the amount of brush biting into the secondary transfer body is stabilized, and the paper dust removal effect is maintained. This is preferable.

  When a cleaning bias is applied to the brush member, it can be mechanically scraped by the rotation of the brush member, and the paper dust can be attracted to the rotating brush member by the electrostatic action of the bias. Since it can improve, it is preferable.

  According to the present invention, by providing a roller-shaped brush member that is rotatable upstream of the cleaning member in the conveyance direction of the secondary transfer member, paper dust on the secondary transfer member is removed before reaching the cleaning member. Trouble that occurs when paper dust is squeezed between the cleaning member and the secondary transfer body, that is, toner filming, transfer paper back contamination and separation failure, and the life of the secondary transfer body Can be prevented. By making the amount of biting at the tip of the brush member relative to the secondary transfer member 1 mm or more, the effect of removing paper dust can be extended.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an electrophotographic color copying machine as an image forming apparatus of a tandem type indirect transfer system according to an embodiment of the present invention. In the figure, reference numeral 100 denotes a copying machine main body as an image forming apparatus main body, 200 denotes a paper feed table on which the copying machine main body 100 is placed, 300 denotes a scanner as an image reading apparatus mounted on the copying machine main body 100, and 400 denotes This is an automatic document feeder (hereinafter referred to as “ADF”) mounted on the scanner 300.

  The copying machine main body 100 is provided with an intermediate transfer belt 10 serving as an endless belt-like intermediate transfer member at the center thereof. The intermediate transfer belt 10 is wound around three support rollers 14, 15, and 16, and is rotated and conveyed clockwise in the drawing by receiving a driving force from a driving source (not shown).

  In the present embodiment, of the three rollers 14, 15, and 16, an intermediate transfer member cleaning device 17 that removes residual toner remaining on the intermediate transfer belt 10 after image transfer is provided on the left side of the roller 16 in the drawing. It is arranged. On the intermediate transfer belt 10 stretched between the first support roller 14 and the second support roller 15, four image forming units 18 of black, yellow, magenta, and cyan are arranged along the transport direction. Are arranged side by side, and these image forming units 18 constitute a tandem image forming unit 20. An exposure device 21 is provided on the tandem image forming unit 20.

  A secondary transfer device 22 is provided on the opposite side of the intermediate transfer belt 10 from the tandem image forming unit 20. The secondary transfer device 22 is configured by spanning an endless secondary transfer belt 24 as a secondary transfer member between two rollers 23. The secondary transfer belt 24 is disposed so as to be pressed against the third support roller 16 via the intermediate transfer belt 10, and transfers the toner image on the intermediate transfer belt 10 onto a transfer sheet P as a transfer material. A fixing device 25 for fixing the transfer image on the transfer paper P is provided beside the secondary transfer device 22. The fixing device 25 is configured by pressing a pressure roller 27 as a pressure member against a fixing belt 26 serving as an endless belt-shaped fixing member heated by heat from a heat source (not shown).

  The secondary transfer device 22 also has a paper transport function for transporting the transfer paper P after image transfer to the fixing device 25. Of course, the secondary transfer member is not limited to a belt-like member, and may be a transfer roller formed of a roller member. However, when the secondary transfer member is constituted by a roller member, it is difficult to provide a sheet conveying function to the fixing device 25 together. In the present embodiment, the transfer device 11 is configured by the secondary transfer device including the secondary transfer belt 22 and the intermediate transfer belt 10.

Below the secondary transfer device 22 and the fixing device 25, a sheet reversing device 28 for reversing the transfer paper P in order to record images on both sides of the transfer paper P in parallel with the tandem image forming unit 20 described above. Image formation by the provided color copier will be described. When making a copy using the color copying machine having the above configuration, first, a document (not shown) is set on the document table 30 of the ADF 400. Alternatively, the ADF 400 is opened, a document (not shown) is set on the contact glass 32 of the scanner 300, and the ADF 400 is closed and pressed by it.

  Next, when a start switch (not shown) is pressed, when the document is set on the ADF 400, the document is transported by the ADF 400 and moved onto the contact glass 32, and then the scanner 300 is driven, and the first traveling body of the scanner is included. 33 and the second traveling body 34 travel.

  When a document is set on the contact glass 32, the scanner 300 is immediately driven, and the first traveling body 33 and the second traveling body 34 travel. At this time, the first traveling body 33 emits light from a light source (not shown) and further reflects the reflected light from the document surface toward the second traveling body 34. The reflected light is further reflected by the mirror of the second traveling body 34 and enters the reading sensor 36 through the imaging lens 35. Thereby, the content of the original is read.

  When the start switch is pressed, one of the support rollers 14, 15 and 16 is rotationally driven by a drive motor (not shown), and the other two support rollers are driven to rotate, and the intermediate transfer belt 10 is rotated and conveyed clockwise. The At the same time, in each image forming unit 8, drum-shaped photoconductors 40Y, 40C, 40M, and 40K as image carriers provided in each image forming unit are rotated, and yellow, cyan, A magenta and black monochrome image is formed. As the intermediate transfer belt 10 is rotated and conveyed, the single color images are arranged inside the intermediate transfer belt 10 and from the primary transfer rollers 62. The image is sequentially transferred onto the surface of the intermediate transfer belt 10 by the primary transfer bias, and a composite color image is formed on the intermediate transfer belt 10.

  When the start switch is pressed, one of the plurality of paper feed rollers 42 provided on the paper feed table 200 is selectively rotated, and the transfer paper P is fed from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43. It is paid out. The fed transfer paper P is separated one by one by the separation roller 45 and introduced into the paper feed path 46, and is conveyed by the conveyance roller 47 and guided to the paper feed path 48 in the copying machine main body 100. It is abutted against the registration roller 49 and stopped. When the manual feed tray 51 provided on the right side wall portion of the copying machine main body 10 is used, the paper feed roller 50 disposed in the vicinity of the tray is rotated, and the transfer paper P on the manual feed tray 51 is fed out. At the same time, the transferred transfer paper P is separated one by one by the separation roller 52 and then introduced into the manual paper feed path 53 and similarly abutted against the registration roller 49 and stopped.

  Thereafter, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer belt 10, and the transfer paper is fed between the intermediate transfer belt 10 and the secondary transfer device 22, and transferred by the secondary transfer device 22. As a result, the color image is secondarily transferred onto the transfer paper P.

  After the image transfer, the transfer paper P is conveyed by the secondary transfer device 22 and sent to the fixing device 25, and heat and pressure are applied by the fixing device 25 to fix the transferred image. By switching, the paper is discharged out of the copying machine main body by the discharge roller 56 and stacked on the paper discharge tray 57 disposed on the left side wall portion of the copying machine main body. On the other hand, in the case of double-sided copying, the transfer paper P on which an image is transferred on one side is introduced into the sheet reversing device 28 by the switching of the switching claw 55 and reversed, and then again the intermediate transfer belt 10 and the secondary transfer belt 24. Are guided to the secondary transfer position where they come into contact with each other, and an image is also recorded on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56.

  On the other hand, the residual toner remaining on the intermediate transfer belt 10 after the image transfer is removed from the intermediate transfer belt 10 after the image transfer by the intermediate transfer body cleaning device 17 to prepare for the image formation again by the tandem image forming unit 20.

  Since the secondary transfer belt 24 is in contact with the intermediate transfer belt 10, the background stain toner and the process pattern on the intermediate transfer belt 10 are transferred between portions where the transfer material such as transfer paper is not placed or between the sheets. In this embodiment, the cleaning device 70 for cleaning the surface of the secondary transfer belt 24 is provided. The cleaning device 70 includes a resin-made secondary transfer cleaning blade 71 serving as a cleaning member that contacts the surface of the secondary transfer belt, and an upstream side of the secondary transfer cleaning blade 71 in the transport direction of the secondary transfer belt 24. It has a roller-like brush member 73 that is rotatably arranged and contacts the surface of the secondary transfer belt 24, and a flicker member 72 that contacts the brush member 73. The brush member 73 is driven to rotate clockwise in this embodiment by a drive motor (not shown), but may be driven to rotate by sliding contact with the secondary transfer belt 24.

  For this reason, the toner on the secondary transfer belt 24 is basically scraped off by the secondary transfer cleaning blade 71, but the paper dust on the secondary transfer belt 24 reaches before the secondary transfer cleaning blade 71. The occurrence of toner filming, which is a problem caused by scraping and removing by the rotation of the brush member 73 and the paper powder being squeezed between the secondary transfer cleaning blade 71 and the secondary transfer belt 24; It is possible to prevent the transfer paper from being stained and poorly separated, and the life of the secondary transfer belt 24 from being reduced. Further, since the flicker member 72 is in contact with the brush member 73, the paper dust adhered to the brush member 73 by scraping from the secondary transfer belt 24 can be removed.

  2 uses a secondary transfer roller 74 as a secondary transfer body in place of the secondary transfer belt 24 shown in FIG. The secondary transfer roller 74 has a structure in which a surface of a fluororesin is coated on the surface of a cylindrical elastic rubber. The secondary transfer roller 74 is rotatably supported by a shaft and is in contact with the intermediate transfer belt 10 at a position facing the support roller 16. A secondary transfer cleaning blade 71 is in contact with the surface of the secondary transfer roller 74. According to such a configuration, since the surface of the secondary transfer roller 74 is coated with the fluororesin, the adhesion force of the toner becomes small and the frictional force with the secondary cleaning blade 71 can be weakened. Further, since the secondary transfer roller 74 is in contact with the intermediate transfer belt 10, the scumming toner and the process pattern on the intermediate transfer belt 10 are transferred between portions where the transfer paper P does not come and between the papers. These are basically removed from the secondary transfer roller 74 by the secondary transfer cleaning blade 71.

  A brush member 73 is disposed on the upstream side of the secondary transfer cleaning blade 71 in the rotational direction of the secondary transfer roller 74 so as to contact the surface of the secondary transfer roller 74. A flicker member 72 is in contact with the brush member 73. The brush member 73 is in contact with the tip of the brush member 73 and the secondary transfer roller 74 with a predetermined biting amount A, and prevents paper dust from being caught in the secondary transfer cleaning blade 71. In the present embodiment, the brush member 73 is biased to further improve the paper dust removal effect and toner removal effect.

  The brush member 73 is made of a polyester resin material so that the outer diameter hardly changes. The roller-like brush member 73 made of polyester resin is characterized in that its outer diameter hardly changes over time. A recovery coil 75 extending in the apparatus depth direction is disposed below the brush member 73. These secondary transfer roller 74, brush member 73, secondary transfer cleaning blade 71, flicker member 72, and recovery coil 75 are housed in a casing 76.

As the brush member 73 in this embodiment, a diameter of 16 mm, an acrylic carbon material of 6.25 D / F, 50,000 pieces / inch ² , E + 7Ω is used, and the same rotation direction as the secondary transfer roller 74 (counter direction) It is rotating at. In this embodiment, the transfer device 22 is configured by the intermediate transfer belt 10, the secondary transfer roller 74, and the like.

  For this reason, the paper powder and toner on the secondary transfer roller 74 scraped off by the brush roller 73 are blown off by the brush member 73 coming into contact with the flicker member 72 made of resin, and are disposed below the brush member 73. The collecting coil 74 is transported to the back side of the apparatus and is transported to a waste toner bottle (not shown).

  Here, FIG. 3 shows the result of passing 50,000 sheets of recycled paper that easily generates paper dust by applying the transfer device 22 of FIG. 2 to the image forming apparatus of FIG. In FIG. 3, the amount of biting A into the secondary transfer roller 74 of the brush member was changed and measured. For reference, the measurement was also performed without the brush member 73.

  When the amount of biting A into the secondary transfer roller 74 by the brush member 73 is less than 1 mm, a cleaning failure has occurred due to paper dust being sandwiched between the secondary transfer cleaning blade 71, but the biting into the secondary transfer roller 74 has occurred. When the amount A was 1 mm or more, cleaning failure did not occur even when 50,000 sheets were passed, and the secondary transfer cleaning blade 71 had almost no paper dust, and the paper dust removal effect by the brush member 73 was obtained.

1 is a diagram illustrating an internal configuration of an image forming apparatus according to an embodiment of the present invention. It is an enlarged view which shows one structural example and the effect | action of a cleaning apparatus. It is a figure which shows the cleaning characteristic by the cleaning apparatus concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Intermediate transfer body 11, 22 Transfer device 18 Image forming unit 24, 74 Secondary transfer body 70 Cleaning device 71 Cleaning member 72 Flicker member 73 Roller-shaped brush member A Biting amount P Transfer material

Claims (6)

In a cleaning device for cleaning the surface of a secondary transfer body that collectively transfers and conveys a toner image transferred to an intermediate transfer body to a transfer material,
The cleaning device is disposed rotatably on the upstream surface of the cleaning member in the transport direction of the secondary transfer body and a cleaning member that contacts the surface of the secondary transfer body, and is disposed on the surface of the secondary transfer body. A cleaning device comprising a roller-shaped brush member in contact with the brush member, wherein an amount of biting of the brush member with respect to the secondary transfer member is 1 mm or more. The cleaning device according to claim 1.
A cleaning device comprising a flicker member in contact with the brush member. The cleaning device according to claim 1 or 2,
The brush member is made of polyester resin. The cleaning device according to claim 1, 2 or 3,
A cleaning device, wherein a cleaning bias is applied to the brush member. An endless intermediate transfer member, which is stretched around a plurality of rollers and rotated and conveyed to transfer toner formed by an image forming unit, and a toner image transferred to the intermediate transfer member are collectively transferred to a transfer material. In a transfer device having a secondary transfer member to be conveyed,
5. A transfer device comprising the cleaning device according to claim 1 as a cleaning device for cleaning a surface of the secondary transfer member. An endless intermediate transfer member that is stretched around a plurality of rollers and rotated and conveyed, an image forming unit that is disposed along the intermediate transfer member to form a toner image, and a toner image transferred to the intermediate transfer member In an image forming apparatus having a secondary transfer body that is collectively transferred to a transfer material and conveyed,
5. An image forming apparatus comprising the cleaning device according to claim 1 as a cleaning device for cleaning a surface of the secondary transfer member.

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