JP2007155992A - Recovered toner classifier and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recovered toner classifier which enhances efficiency of passing through meshes to prevent the deterioration with time of a filter function by generating an electric field which positively charges recovered toner to guide the recovered toner out of a filter; and also to provide an image forming apparatus. <P>SOLUTION: In the recovered toner classifier used to recycle toner in the image forming apparatus, a plurality of netlike members different by mesh size are arranged in series so that the mesh size increases in a toner conveyance direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a recycled (collected) toner classifying device, and more particularly to a collected toner classifying device and an image forming apparatus having a function of removing fine powder toner in the toner from the collected toner.

In a collected toner classification device using a conventional filter, only a certain amount of toner or paper dust is removed by a single filter, and fine powder toner is recycled without being removed.
However, fine powder toner is easy to film on a charge imparting member such as a carrier and a photosensitive member, so that it may cause early deterioration of the developer or the toner coating on the carrier may be substantially increased. The toner in the agent will be in an over shape, causing toner scattering and background contamination, and causing various problems such as charging roller contamination due to poor cleaning performance. It is desirable.

  Conventionally, a plurality of mesh-shaped separation means with different eyes are arranged vertically on the toner disposal path, and the toner is transferred from the rough-eye separation means to the fine-eye separation means, and there is no toner charging means or the like and recycling. There has been proposed a method that does not have a function of selecting a suitable toner (see, for example, Patent Document 1).

  In addition, a method has been proposed in which a vibration tank is provided in a conveyance path for returning the collected toner to the developing unit to remove a non-reusable derivative (for example, see Patent Document 2).

  In addition, a method has been proposed in which a cylindrical filter means for passing toner to be reused is rotated, and a fiber or resin brush is applied to the inside and outside of the filter means to prevent toner adhesion (for example, Patent Documents). 3).

In addition, a recycled toner classification device using a mesh is specifically disclosed (for example, see Patent Documents 4 and 5).
Japanese Patent No. 3570706 JP-A-10-133533 JP 2001-51570 A JP 2003-287958 A JP 2001-175137 A

  However, in the recycled toner classifying apparatus using the conventional filter, there is a problem that the toner passing efficiency of the mesh of the filter is poor and a lot of toner is thrown away without being recycled.

  The present invention has been made in view of the above-described circumstances, and positively charges the toner, generates an electric field that induces the toner to the outside of the filter, increases the efficiency of passing the toner through the mesh, and adheres to the filter. The toner is physically removed, and the fine toner is first removed by a filter with the first mesh that has a plurality of mesh size filters arranged in series, and problems such as image deterioration due to the fine powder toner are removed. It is an object of the present invention to provide a recovered toner classifying device and an image forming apparatus that can increase the recovery efficiency and prevent deterioration of the filter function with time.

  In order to solve the above-described problem, the invention according to claim 1 is a recovery toner classifying device for recycling and using toner of an image forming apparatus, wherein a plurality of mesh members having different meshes are arranged in the toner transport direction. The meshes are arranged in series so that the meshes become larger in order.

  According to a second aspect of the present invention, in the collected toner classifying device according to the first aspect, the smallest mesh member located in the uppermost stream in the toner conveying direction has conductivity, and the mesh A conductive member is provided outside the member, and a voltage is applied between the conductive member and the mesh member.

  According to a third aspect of the present invention, in the collected toner classifying apparatus according to the first or second aspect, a toner charge accelerating member is provided in the mesh member to charge the toner.

  According to a fourth aspect of the present invention, in the collected toner classifying device according to the third aspect, a conductive member is provided outside the mesh member, and a voltage is applied between the conductive member and the mesh. Features.

  According to a fifth aspect of the present invention, there is provided the collected toner classifying device according to any one of the first to fourth aspects, wherein in the collected toner classifying device, at least one mesh member of the mesh member in the toner conveyance direction is provided. A non-conductive brush is provided on the outside so as to contact the mesh.

  According to a sixth aspect of the present invention, there is provided an image forming apparatus having the collected toner classifying device according to any one of the first to fifth aspects.

  According to the present invention, in a collected toner classification device for recycling and using toner of an image forming apparatus, a plurality of mesh members having different meshes are provided in series so that the meshes increase in order in the toner conveyance direction. The recovered toner classifier can remove fine toner and toner that has agglomerated to a large particle size, sharpening the particle size distribution of recycled toner and preventing image deterioration. It becomes possible.

  In addition, the recovered toner classification device is characterized in that a metal plate is provided outside the fine powder waste filter and a voltage is applied between the metal plate and the mesh. As a result of this friction, the charged toner can easily move out of the mesh, and the fine toner removal efficiency can be increased.

  Furthermore, a recovered toner classifying device having a fur brush or a blade in the recovery filter and charging the toner can charge a large amount of toner and increase the recycling toner recovery efficiency.

  Further, since the non-conductive brush is provided outside the collection filter so as to be in contact with the mesh, the collection filter is not clogged and the collection filter does not deteriorate with time.

Hereinafter, a collected toner classification device of the present invention will be described in detail based on an embodiment with reference to the drawings.
FIG. 1 is an explanatory diagram for explaining the flow of toner recycling in an embodiment of the toner classifying apparatus according to the present invention.
In the image forming apparatus, toner moves from the developing unit 1 to the electrostatic image carrier drum 2 in accordance with the latent image, and the toner on the drum is transferred to paper or an intermediate transfer belt. At this time, some toner remains on the drum without being transferred. The toner remaining on the drum is collected by the cleaning unit 3. In the image forming apparatus according to the present invention that performs toner recycling, the toner collected by the cleaning unit is used for recycling.

This also applies to other conventional image forming apparatuses that perform toner recycling.
The flow of toner recycling according to the present invention will be described in detail with reference to FIG.
The toner 4 on the drum 2 collected by the cleaning unit 3 is conveyed to a collected toner classifying device 5 surrounded by a one-dot chain line.
Here, the toner 4 is classified into three: a fine powder toner 6 (fine powder waste toner) classified by the fine powder waste filter 10, a collected toner 7 classified by the collection filter 11, and a large particle size waste toner 8. . The collected toner 7 is transported to the developing device and recycled. Other fine powder waste toner 6 and large particle size waste toner 8 are conveyed to a waste toner tank 9 and discarded.

Details of the collected toner classifier 5 are shown in FIGS.
FIG. 2 is a front view of the collected toner classifier, and FIGS. 3 and 4 are cross-sectional views taken along lines III-III and IV-IV in FIG. 2, respectively.
The fine powder waste toner 6 is classified by the fine powder waste filter 10 of FIG. 2 and discarded as waste toner, and the recovered toner 7 passes through the recovery filter 11 and is recycled.

3 and FIG. 4 includes a fur brush 13 as a charge accelerating member, a non-conductive brush roller 14, and a conductive member 15 for forming a toner discharge accelerating electric field.
The toner collected in the meshes of the fine powder disposal filter 10 and the collection filter 11 passes through each mesh by mesh eyes so that when the collection filter 11 rotates, the toner is conveyed in the direction from left to right on the paper surface. However, the toner that has been transported into the collection filter 11 is always transported in the direction from the left to the right of the paper as the rotary classifier rotates.

  The toner conveyed to the collected toner classifier first enters the fine powder disposal filter 10. Here, the toner is frictionally charged by the fur brush 13, and the pulverized toner having a diameter smaller than that of the pulverized waste filter 10 receives a force due to an electric field toward the conductive member outside the pulverized waste filter 10, Move to. The fine toner adhering to the conductive member is discarded. As described above, after the frictional charging, the fine powder toner is classified and repeatedly attracted by the electric field force to the conductive member many times, and the toner in which the fine powder toner is gradually decreased moves toward the recovery filter 11. The toner conveyed into the collection filter 11 is also moved to the conductive member in the same manner as in the fine powder disposal filter 10.

  However, the toner transferred to the conductive member here is a toner component that is recovered rather than discarded, and the recovered toner component is recycled to the developing unit. The remaining components of the toner conveyed to the outside of the recovery filter 11 after repeating the act of frictionally charging in this way and repeating the action that the toner smaller than the mesh of the recovery filter 11 passes through the recovery filter 11. Are also discarded.

FIG. 5 shows the classification effect of the recovered toner classification apparatus of the present invention.
When the recovered toner classifying apparatus of the present invention is used, the amount of fine powder toner is smaller than that of the conventional particle size distribution of only the recovery filter, the particle size distribution becomes sharp, and high recycling efficiency can be obtained.

  Further, since the non-conductive brush roller is installed in the collected toner classifying device of the present invention, the filter did not deteriorate with time. In addition, although the collection | recovery toner classification apparatus of this invention was demonstrated as a structure which has two filters, a fine powder waste filter and a collection filter, the number of these filters does not need to be limited. That is, in the present invention, it is important that the mesh of the filter is arranged in series continuously from small to large in the moving direction of the collected toner, and at least one of the plurality of filters is used. Can be provided with a non-conductive brush on the outside so as to contact the mesh.

  The above-described embodiment shows an example of a preferred embodiment of the present invention, and the present invention is not limited thereto, and various modifications can be made without departing from the scope of the invention. is there.

FIG. 4 is an explanatory diagram for describing a flow of toner recycling in an embodiment of the toner classification device according to the present invention. It is a front view of a collected toner classification device. It is sectional drawing along the III-III line of FIG. It is sectional drawing along the IV-IV line of FIG. It is a figure which shows the effect of the classification | category of the collection | recovery toner classification apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Developing unit 2 Electrostatic image carrier drum 3 Cleaning unit 4 Toner 5 Collected toner classification device 6 Fine powder toner (fine powder waste toner)
7 Collected toner 8 Large particle size waste toner 9 Waste toner tank 11 Collection filter 13 Fur brush 14 Non-conductive brush roller 15 Conductive member

Claims (6)

  In a collected toner classification device for recycling and using toner of an image forming apparatus, a plurality of mesh members having different meshes are arranged in series so that the meshes increase in order with respect to the toner conveying direction. A collected toner classification device.   The mesh member with the smallest mesh located in the uppermost stream in the toner conveying direction has conductivity, and a conductive member is provided outside the mesh member, and the conductive member and the mesh member are disposed between the conductive member and the mesh member. The recovered toner classifier according to claim 1, wherein a voltage is applied.   3. The collected toner classifying apparatus according to claim 1, wherein a toner charge accelerating member is provided in the mesh member to charge the toner.   4. The collected toner classification device according to claim 3, wherein a conductive member is provided outside the mesh member, and a voltage is applied between the conductive member and the mesh.   5. The collected toner classification device according to claim 1, wherein a non-conductive brush is provided outside the at least one mesh member in the toner conveying direction so as to be in contact with the mesh.   An image forming apparatus comprising the collected toner classifying device according to claim 1.

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