JP2005156917A - Intermediate transfer unit for image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intermediate transfer unit, in which a recovery bottle is disposed in an area where a setting space is sufficiently obtained, and a large capacity recovery bottle provided integrally with the intermediate transfer unit is realized, thereby eliminating the need for replacement for only the recovery bottle, the frequency of the replacement of the large capacity recovery bottle along with the intermediate transfer unit is reduced, and a simple structure for protecting an intermediate transfer belt, when temporarily placing the intermediate transfer unit is provided, thereby improving operability. <P>SOLUTION: The large capacity recovery bottle is disposed integrally with the intermediate transfer unit on the transfer side of the intermediate transfer belt and opposite an image carrier, as viewed from the intermediate transfer belt, which is an area where the large capacity recovery bottle does not interfere with components such as a cleaning member and a second transfer roller. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a configuration of an intermediate transfer unit in an image forming apparatus using an electrophotographic system, such as a computer printer or a copying machine.

  In an image forming apparatus using an electrophotographic system, an image is formed by electrostatically adsorbing powdered toner. Among them, the method using the intermediate transfer member first transfers the toner image formed following the electrostatic latent image from the image carrier to the intermediate transfer member, and then the recording material such as paper or plastic sheet from the intermediate transfer member. Since the toner image is transferred, the image is finally formed on the recording medium.

  In the image forming apparatus having a toner transfer process, a mechanism for cleaning and collecting the transfer residual toner is necessary, and a cleaning member such as a rubber blade is brought into contact with the intermediate transfer member, so that the transfer residual toner is scraped off. A cleaning method is generally employed, and the transfer residual toner scraped off is accumulated and recovered in a recovery bottle or the like. When the recovery bottle becomes full of the transfer residual toner, the recovery bottle is replaced.

  In recent years, for the purpose of improving operability, in order to reduce the frequency of replacing the collection bottle or to eliminate the replacement work, it is required to increase the capacity of the collection bottle. 5 and 6 are a sectional view and a plan view showing an example of the configuration of an intermediate transfer unit and a recovery bottle of a conventional image forming apparatus. The conventional recovery bottle 7 is provided in the vicinity of the cleaning member 1f because it is scraped off by the cleaning member 1f and then accumulates and recovers the transfer residual toner 5 transferred by the transfer means 8 by free fall. When considering the recovery bottle 7 that does not interfere with the traveling path of the recording medium 6 as a component such as the cleaning member 1 f and the second transfer roller 3, it is difficult to secure a space other than increasing the size of the image forming apparatus itself. Therefore, it was difficult to increase the capacity of the recovery bottle 7.

  Further, in the operation of replacing the collection bottle 7 that is full of the transfer residual toner 5, there is a problem that the transfer residual toner 5 scatters from the connection port and stains the image forming apparatus and the replacement operator with the transfer residual toner 5. there were.

  Japanese Patent Application Laid-Open No. 2002-62776 proposes a configuration in which a recovery bottle is provided inside the intermediate transfer belt of the intermediate transfer unit in order to reduce the size of the image forming apparatus while securing the installation space of the recovery bottle. In view of the downsizing of the image forming apparatus, the intermediate transfer unit is also downsized, and the arrangement of the first transfer roller and the like, there is a limit to securing the recovery bottle space inside the intermediate transfer belt, There is an upper limit to increasing the capacity of the collection bottle.

  In order to protect the surface of the intermediate transfer belt from scratches when temporarily placing the intermediate transfer unit during maintenance, a protective cover for the intermediate transfer belt is required, or the intermediate transfer unit Since a dedicated stand is required, the configuration is complicated, leading to an increase in cost.

  Therefore, a collection bottle is placed in an area where sufficient installation space can be secured, and a large-capacity collection bottle that can accumulate and collect the amount of residual toner that is expected to be collected during the lifetime of the intermediate transfer belt is integrated with the intermediate transfer unit. In addition, it is necessary to simply provide a structure for protecting the intermediate transfer belt when the intermediate transfer unit is temporarily placed during maintenance.

  As described above, in the conventional image forming apparatus, it is difficult to increase the capacity of the collection bottle when considering the downsizing of the image forming apparatus. Also, when replacing the collection bottle, the image forming apparatus or the replacement operator is not used. There is a problem that the toner is soiled with the transfer residual toner.

  Furthermore, considering the temporary placement of the intermediate transfer unit during maintenance, etc., providing a configuration for protecting the intermediate transfer belt has led to an increase in cost.

  An object of the present invention is to arrange a collection bottle in an area where a sufficient installation space can be secured, and to realize a large-capacity collection bottle integrally provided in the intermediate transfer unit. The operability is reduced because the replacement frequency of the large-capacity collection bottle that is exchanged with the intermediate transfer unit is reduced, and the intermediate transfer belt is protected when the intermediate transfer unit is temporarily placed. Is to provide an improved intermediate transfer unit.

  The above-described problem is that the intermediate transfer unit is located on the transfer surface side of the intermediate transfer belt and on the opposite side of the image carrier as viewed from the intermediate transfer belt, which is an area that does not interfere with components such as the cleaning member and the second transfer roller. This is achieved by providing a large-capacity recovery bottle integrally.

  Also, an opening serving as an entrance for the transfer residual toner to be recovered is provided above the large-capacity recovery bottle, and the transfer residual toner scraped off by the cleaning member and temporarily accumulated in the toner collecting container is Since the first conveying means and the second conveying means for conveying to the opening of the recovery bottle are provided, the transfer residual toner can be efficiently deposited in the space in the large-capacity recovery bottle by free fall.

  According to the present invention, it is possible to realize a large-capacity recovery bottle having a predetermined capacity capable of accumulating and recovering a transfer residual toner amount expected to be recovered during the lifetime of the intermediate transfer belt, and integrated with the intermediate transfer unit. Large capacity recovery bottles can be provided.

  Therefore, there is no need to replace only the recovery bottle, so there is no problem that the transfer residual toner is scattered from the connection port, and the operability is improved because the frequency of replacement of the recovery bottle to be replaced with the intermediate transfer unit is reduced. Furthermore, when the intermediate transfer unit is temporarily placed, a configuration for protecting the intermediate transfer belt from the large-capacity recovery bottle covering the intermediate transfer belt can be easily realized.

(Example 1)
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  First, the configuration of the image forming apparatus and the intermediate transfer member unit will be described.

  The image forming apparatus mainly includes an intermediate transfer unit 1, a developing device 2, an image carrier 2a, a second transfer roller 3, and a motor 4. The intermediate transfer unit 1 mainly includes an intermediate transfer belt 1a, The driving roller 1b, the driven roller 1c, the frame 1d, the first transfer roller 1e, the cleaning member 1f, the toner collecting container 1g, the large-capacity collection bottle 1h, the first conveying unit 1k, and the second conveying unit 1m are included.

  In the developing device 2, there is an image carrier 2a (four in this embodiment) that carries toner in accordance with the electrostatic latent image and rotates in the direction A in the figure, and the image carrier 2a rotates in the direction B in the figure. Is disposed adjacent to the intermediate transfer belt 1a. As viewed from the image carrier 2a, a second transfer roller 3 that rotates in the C direction in the figure is disposed adjacent to the intermediate transfer belt 1a downstream of the intermediate transfer belt 1a in the rotation direction.

  A drive roller 1b, a driven roller 1c, and a first transfer roller 1e are provided inside the intermediate transfer belt 1a. The drive roller 1b is connected to the motor 4 when the intermediate transfer unit 1 is attached to the image forming apparatus. In this position, the driven roller 1c faces the second transfer roller 3, and the first transfer roller 1e (four in this embodiment) faces each image carrier 2a via the intermediate transfer belt 1a. Thus, they are arranged at positions where they abut against the image carrier 2a, and are rotatably supported by the frame 1d.

  The cleaning member 1f is disposed upstream of the first transfer roller 1e and downstream of the driven roller 1c in the rotational direction of the intermediate transfer belt 1a, and is in contact with the intermediate transfer belt 1a.

  The large-capacity recovery bottle 1h has an opening F on the upper side, is an area on the transfer surface side of the intermediate transfer belt 1a, and an area that does not interfere with components such as the cleaning member 1f and the second transfer roller 3. Since it is disposed on the opposite side of the image carrier 2a as viewed from the belt 1a and is fixed to the frame 1d with screws or the like, it is detachably attached to the intermediate transfer unit 1. The large-capacity recovery bottle 1h has a capacity capable of accumulating and recovering the amount of transfer residual toner 5 that is expected to be recovered during the lifetime of the intermediate transfer belt 1a.

  Immediately below the cleaning member 1f, there is provided a toner collecting container 1g in which the transfer residual toner 5 that has been scraped off is temporarily accumulated, and a screw or the like rotates in the toner collecting container 1g to rotate the toner collecting container. A first conveying means 1k for conveying the untransferred toner 5 to 1 g of one end E is provided. Further, in the next process of the first conveying means 1k, a belt with ribs or the like rotates to pump up the transfer residual toner 5, so that the transfer residual toner 5 is transferred upward to the opening F of the large-capacity recovery bottle 1h. A second conveying means 1m for conveying is provided. In this embodiment, since the ribbed belt as the second conveying means 1m also serves as power transmission to the screw as the first conveying means 1k, the first conveying means 1k and the second conveying means 1m are interlocked. To operate.

  Next, operations of the image forming apparatus and the intermediate transfer unit will be described.

  In the developing device 2, the toner image formed on the surface of the image carrier 2 a following the electrostatic latent image has a potential difference between the image carrier 2 a and the intermediate transfer belt 1 a, and the electrostatic attraction force has a large or small difference. Therefore, the image is transferred to the intermediate transfer belt 1a. Thereafter, the intermediate transfer belt 1 a rotates in the B direction in the drawing, and the formed toner image is conveyed to a contact point with the second transfer roller 3. Here, when a recording medium 6 such as paper or a plastic sheet is sandwiched and conveyed between the intermediate transfer belt 1 a and the second transfer roller 3, a potential difference is generated between the intermediate transfer belt 1 a and the second transfer roller 3. Since the difference is provided in the electrostatic attraction force, the toner image is transferred to the surface of the recording medium 6 and a toner image is formed on the recording medium 6.

  At this time, not all toner images forming an image on the surface of the intermediate transfer belt 1a have the same level of electrostatic attraction, and the toner image is transferred from the intermediate transfer belt 1a to the recording medium 6. In this case, there is a case where the residual toner 5 is not transferred but remains adsorbed to the intermediate transfer belt 1a. Since the intermediate transfer belt 1a sequentially repeats the image transfer process from the developing device 2a and the image transfer process to the recording medium 6, the image transfer process to the recording medium 6 and the image transfer process from the developing apparatus 2 are performed. The transfer residual toner 5 needs to be removed from the surface of the intermediate transfer belt 1a between the toner and the transfer residual toner 5 on the surface of the intermediate transfer belt 1a by the cleaning member 1f, so that the intermediate transfer belt 1a is cleaned. I do.

  When the motor 4 is driven, the driving roller 1b rotates, the intermediate transfer belt 1a is conveyed, and the first conveying unit 1k and the second conveying unit 1m are also operated. The transfer residual toner 5 scraped off by the cleaning member 1f is first temporarily accumulated in the toner collecting container 1g, and one end portion in the toner collecting container 1g is rotated by the rotation of the screw as the first conveying means 1k. To E. Thereafter, the ribbed belt as the second conveying means 1m rotates in the direction D in the drawing, whereby the transfer residual toner 5 is continuously drawn up and conveyed upward from the portion E in the drawing. The transfer residual toner 5 conveyed upward falls at the opening F of the large-capacity recovery bottle 1h, and is deposited and collected in the large-capacity recovery bottle 1h by free-falling.

  Here, the opening F is provided above the large-capacity recovery bottle 1h, and the transfer residual toner 5 deposited in the free fall in the large-capacity recovery bottle 1h is recovered at a high filling rate. The capacity of 1h can be used effectively. Since there are no components such as the cleaning member 1f and the second transfer roller 3 around the large-capacity recovery bottle 1h, the transfer in which the capacity of the large-capacity recovery bottle 1h is predicted to be recovered during the lifetime of the intermediate transfer belt 1a. Since the capacity of the remaining toner 5 or more is set to a capacity that can be accumulated and recovered, the replacement work frequency of the large capacity recovery bottle 1h can be reduced.

  In this embodiment, for example, when the life of the intermediate transfer belt 1a is 500 hours and the amount of residual toner 5 recovered from the intermediate transfer belt 1a in 500 hours is 2000 cc, the capacity of the large-capacity recovery bottle 1h Is 2000 cc or more.

  Since the life of the large-capacity recovery bottle 1h is longer than that of the intermediate transfer belt 1a, the large-capacity recovery bottle 1h can be integrally provided in the intermediate transfer unit 1 without any harmful effects, and only the large-capacity recovery bottle 1h is replaced. There is no work to do.

  Further, when the intermediate transfer unit 1 is temporarily placed during replacement work or the like, since the large-capacity recovery bottle 1h covers the intermediate transfer belt 1a, the intermediate transfer belt 1a is protected with a simple configuration. be able to.

1 is a cross-sectional view showing main parts of an image forming apparatus and an intermediate transfer unit according to a first embodiment of the present invention. FIG. 3 is a cross-sectional view illustrating a main part of the intermediate transfer unit according to the first embodiment of the present invention. FIG. 3 is a plan view showing a main part of the intermediate transfer unit according to the first embodiment of the present invention. FIG. 3 is a perspective view showing a state where the intermediate transfer unit according to the first embodiment of the present invention is temporarily placed. It is sectional drawing which shows the principal part of the intermediate transfer unit in a prior art, and a collection | recovery bottle. It is a top view which shows the principal part of the intermediate transfer unit and collection | recovery bottle in a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Intermediate transfer unit 1a Intermediate transfer belt 1b Drive roller 1c Driven roller 1d Frame 1e First transfer roller 1f Cleaning member 1g Toner collection container 1h Large-capacity collection bottle 1k First transport unit 1m Second transport unit 2 Developing device 2a Image carrier 3 Second transfer roller 4 Motor 5 Transfer residual toner 6 Recording medium 7 Collection bottle 8 Conveying means A, B, C, D Rotation direction E, F part

Claims (3)

One or a plurality of image carriers that form a toner image on the surface following the electrostatic latent image;
An endless belt-like intermediate transfer belt that is adjacent to the image carrier and carries a toner image transferred from the image carrier on its surface, a driving roller that stretches the intermediate transfer belt, and drives and conveys the intermediate transfer belt; A first transfer roller disposed on the inner side of the intermediate transfer belt corresponding to the image carrier, a cleaning member for scraping off and cleaning the transfer residual toner on the surface of the intermediate transfer belt, and scraped off. An intermediate transfer unit comprising a toner collecting container in which transfer residual toner temporarily accumulates;
A collection bottle in which the transfer residual toner cleaned by the cleaning member is collected and accumulated;
In an image forming apparatus comprising a second transfer roller that collectively transfers a toner image formed on the intermediate transfer belt to a recording material such as paper or a plastic sheet,
The collection bottle is provided integrally with the intermediate transfer unit, and is disposed on the transfer surface side of the intermediate transfer belt and on the opposite side of the image carrier as viewed from the intermediate transfer belt. An intermediate transfer unit for an image forming apparatus.   The collection bottle has at least one opening portion serving as an entrance for the collected transfer residual toner, and has a first conveyance unit configured to convey the transfer residual toner in the toner collection container in a substantially horizontal direction; The transfer residual toner is conveyed to the opening of the recovery bottle by providing a second conveyance unit that conveys the transfer residual toner conveyed by the first conveyance unit upward. Intermediate transfer unit. The intermediate transfer unit according to claim 1, wherein the recovery bottle has a capacity capable of accumulating and recovering a transfer residual toner amount that is expected to be recovered during the lifetime of the intermediate transfer belt.

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