JP2004045904A - Toner classifier, and processing cartridge and image forming device having classifier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner classifier in which efficient classification is conducted to prevent the occurrence of clogging regardless of the amount of toner being transported into the classifier and occurrence of failure such as locking or the like is eliminated by surely ejecting unclassified toner out of the classifier, to provide a processing cartridge having the classifier and an image forming device. <P>SOLUTION: A sieve member 11 is provided to classify toner T1 which is transported in from an entrance 11d and out from an exit 11b. Toner T3 which is not classified among the toner T1 is transported out toward the exit 11b, and a flexible member 15 is provided to nonhomogeneously slide and contact with the inner wall of the member 11. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a toner classifier, a process cartridge including the same, and an image forming apparatus, and more particularly, to a copier, a printer, a facsimile using an electrophotographic method, or a composite machine thereof, on an image carrier. The present invention relates to a toner classification device for collecting and recycling residual toner, a process cartridge including the same, and an image forming apparatus.
[0002]
[Prior art]
In recent years, in consideration of effective use of resources, after collecting the remaining toner on the photosensitive drum as an image carrier, the toner is classified into recyclable toner and unrecyclable toner, and the recyclable toner is developed into a developing unit. An image forming apparatus which is used by supplying it to a computer has been actively developed.
[0003]
Specifically, referring to, for example, Japanese Patent Application Laid-Open No. H10-260583, first, the residual toner on the photosensitive drum that has not been transferred to the transfer paper in the transfer unit is collected in the cleaning unit. The residual toner (recovered toner) collected by the cleaning unit is supplied to the toner classification device via the toner transport unit.
In the residual toner, there are paper dust adhered to the photosensitive drum from the transfer paper and agglomerated lump of the toner. If the residual toner including the paper dust and the toner lump is supplied as it is to the developing unit as a recycled toner, an abnormal image such as white spots or black spots is generated. Therefore, the toner is removed by a toner classification device.
[0004]
Here, the toner classification device includes a rotating cylindrical sieve member made of a net-like metal wire or the like. Since the paper dust and the toner lump are larger than the particle diameter of the toner, they cannot pass through the mesh of the sieve member.
In this way, the toner (classified toner) passing through the screen of the sieve member is supplied to the developing unit as recycled toner. On the other hand, the toner that does not pass through the screen of the sieve member is discharged as waste toner from an outlet of the toner classification device and collected in a waste toner container.
[0005]
Further, in such a toner classifying apparatus, a technique of sliding a brush member on a part of an inner wall of a sieve member in order to prevent clogging of toner in a mesh portion of the sieve member is disclosed in, for example, Japanese Patent Application Laid-Open No. H10-260583. And Japanese Patent Laid-Open Publication No. 2000-200020.
[0006]
[Problems to be solved by the invention]
In the above-described conventional toner classification device, it is difficult to prevent clogging and to surely convey the toner toward the outlet of the sieve member regardless of the amount of toner carried into the device.
[0007]
In other words, when an image having a high image ratio is formed on the image carrier of the image forming apparatus, the amount of residual toner collected by the cleaning unit increases in proportion to that, and the amount of toner transferred into the toner classification device also increases. To increase.
At this time, if the amount of the brush that slides on the inner wall is small relative to the amount of the toner carried into the sieve member, the scraping by the brush member becomes insufficient, the mesh portion is clogged with the toner, and the classification performance of the apparatus is reduced. Will decrease.
[0008]
On the other hand, even if the amount of the brush that slides on the inner wall of the sieve member of the brush member is simply increased, since the brush member hinders the toner transportability, the toner stagnates at the entrance side of the sieve member. It will encourage you rather than get clogged. Further, there is a possibility that the toner stagnant on the entrance side may enter between the conveying unit on the entrance side and the rotating sieve member to cause locking.
[0009]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and performs efficient classification by preventing clogging regardless of the amount of toner carried into the apparatus. It is an object of the present invention to provide a toner classifying device that reliably discharges toner to a printer and does not cause a problem such as locking, a process cartridge provided with the same, and an image forming apparatus.
[0010]
[Means for Solving the Problems]
The inventor of the present application has conducted studies to solve the above-mentioned problems, and as a result, has come to know the following matters.
That is, if a flexible member such as a brush member that slides on the inner wall of the sieve member is formed in a helical shape, the amount of the brush that slides on the inner wall can be increased to prevent clogging of the mesh portion, and the toner flowing toward the outlet can be prevented. Transportability can be ensured.
[0011]
Moreover, by intentionally sliding the spiral brush member unevenly against the inner wall of the sieve member, even when a large amount of toner is carried into the sieve member, the uneven sliding contact is made. The portion serves as an escape route for the toner, so that clogging can be prevented.
[0012]
Furthermore, even when the spiral brush member is uniformly slid against the inner wall of the sieve member, the toner conveyance is performed by changing the rotation speed of the brush member according to the amount of toner carried into the sieve member. By adjusting the force, stagnation of the toner on the entrance side can be prevented.
[0013]
The present invention is based on the matters described above, that is, a toner classifying apparatus according to the invention of claim 1 of the present invention, a sieve member for classifying a toner carried in from an inlet until the toner is carried out to an outlet, And a flexible member that transports the unclassified toner among the toner toward the outlet and slidably contacts the inner wall of the sieve member in a non-uniform manner.
[0014]
Further, in the toner classification device according to the second aspect of the invention, in the first aspect of the invention, the sieve member is cylindrical and rotatably formed, and the flexible member is the sieve. The rotatable member is formed so as to be rotatable in the same or opposite direction as the rotation direction of the member, and the center of rotation of the sieve member and the center of rotation of the flexible member do not match.
[0015]
According to a third aspect of the present invention, in the toner classifying apparatus according to the first or second aspect, a shaft portion provided with a transport screw that guides the toner toward the entrance of the sieve member. And a rotating shaft having a shaft provided with the flexible member, the center of rotation of the shaft provided with the transport screw, and the center of rotation of the shaft provided with the flexible member, It is a disagreement.
[0016]
According to a fourth aspect of the present invention, in the toner classification device according to any one of the first to third aspects, the flexible member is formed in a spiral shape with respect to the toner conveying direction. This is a shaped brush member.
[0017]
According to a fifth aspect of the present invention, in the toner classification apparatus according to any one of the first to fourth aspects, the flexible member is formed in a spiral shape with respect to the toner conveying direction. A first brush member formed with a gap, and a second brush member spirally formed so as to fill a part or the entirety of the gap and having a lower bristle height than the first brush member It consists of:
[0018]
According to a sixth aspect of the present invention, in the toner classifying apparatus according to any one of the first to fourth aspects, the flexible member is spirally formed in the toner conveying direction. A brush member is formed with a gap, and the gap on the inlet side is formed to be larger than the gap on the outlet side.
[0019]
According to a seventh aspect of the present invention, there is provided a toner classifying apparatus, comprising: a sieve member for classifying a toner carried in from an inlet until the toner is carried out to an outlet; and conveying the toner not classified among the toners to the outlet. A flexible member slidably in contact with an inner wall of the sieve member, wherein a force of conveying the toner by the flexible member is changed according to an amount of the toner carried in from the entrance.
[0020]
Also, in the toner classification device according to the invention of claim 8, in the invention of claim 7, the sieve member is cylindrical and rotatably formed, and the flexible member is A brush member spirally formed with respect to a toner conveying direction, the brush member being formed so as to be rotatable in the same direction as or a direction opposite to the rotation direction of the sieve member, and in accordance with the amount of toner carried in from the entrance. Thus, the number of rotations of the flexible member is changed.
[0021]
A process cartridge according to a ninth aspect of the present invention includes the toner classification device according to any one of the first to eighth aspects.
[0022]
According to a tenth aspect of the present invention, there is provided a process cartridge according to the ninth aspect, wherein the image carrier, a developing unit for supplying toner onto the image carrier, and a residual member on the image carrier are provided. A cleaning unit that collects toner, the remaining toner collected by the cleaning unit is transported toward the entrance of the toner classification device, and the toner that has been classified by the sieve member of the toner classification device is It is supplied to the developing section.
[0023]
An image forming apparatus according to an eleventh aspect of the present invention includes the toner classification device according to any one of the first to eighth aspects.
[0024]
An image forming apparatus according to a twelfth aspect of the present invention is the image forming apparatus according to the eleventh aspect, wherein the image carrier, a developing unit that supplies toner onto the image carrier, A cleaning unit that collects residual toner, wherein the residual toner collected by the cleaning unit is transported toward the entrance of the toner classification device, and is classified by the sieve member of the toner classification device. Is supplied to the developing section.
[0025]
An image forming apparatus according to a thirteenth aspect of the present invention is the image forming apparatus according to the twelfth aspect, wherein the detecting unit detects an operating rate of a light source that emits light toward the image carrier, and And a control unit that controls the drive unit in accordance with the detection result of the detection unit.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each of the drawings, the same or corresponding portions are denoted by the same reference characters, and description thereof will be appropriately simplified or omitted.
[0027]
Embodiment 1 FIG.
Embodiment 1 will be described in detail with reference to FIGS. FIG. 1 is a schematic sectional view showing the vicinity of the photosensitive drum of the image forming apparatus according to the first embodiment. Then, the toner classification device shown in FIGS. 2 and 3 is installed in the image forming apparatus shown in FIG.
[0028]
In FIG. 1, reference numeral 1 denotes a photosensitive drum as an image carrier, 2 denotes a charging unit that charges the surface of the photosensitive drum 1, and 3 denotes a developing unit that develops a latent image on the photosensitive drum 1 formed by a laser beam L. Reference numeral 4 denotes a transfer unit that transfers an image formed on the photosensitive drum 1 to transfer paper, 5 denotes a cleaning unit that collects residual toner on the photosensitive drum 1 that has not been transferred to the transfer paper, and 6 denotes a cleaning unit 5 A toner transport unit for transporting the residual toner collected in the above to a toner classifying device, 7 a toner classifying device for classifying the residual toner into a recyclable classifying toner and a non-recyclable waste toner, and 8 a toner classifying device. A waste toner path through which the discharged waste toner is conveyed, and reference numeral 9 denotes a waste toner container for collecting the waste toner.
[0029]
The image forming apparatus configured as described above operates as follows.
First, the surface of the photoconductor drum 1 is uniformly charged at a position facing the charging unit 2. Then, the surface of the photosensitive drum 1 charged by the charging unit 2 reaches the irradiation position of the laser beam L by rotating in the direction of the arrow in FIG.
[0030]
On the other hand, image information of a document placed on a document reading unit (not shown) is optically read by the document reading unit. Then, after the optical image information is converted into an electric signal, it is transferred to an optical unit (not shown). Then, a laser beam L based on the image information of the electric signal is emitted from the optical unit toward the charged photosensitive drum 1.
Thus, an electrostatic latent image corresponding to the image information of the document is formed on the photosensitive drum 1.
[0031]
Thereafter, the surface of the photosensitive drum 1 on which the electrostatic latent image is formed reaches a position where the developing unit 3 faces the developing roller 3a. Then, the toner of the two-component developer carried on the developing roller 3a adheres to the electrostatic latent image on the surface of the photosensitive drum 1.
More specifically, fresh toner is supplied from a toner container (not shown) to the toner replenishing unit 3d of the developing unit 3, and classified toner as recycled toner is supplied from the toner classifying device 7. Then, the toner including the recycled toner is appropriately supplied into the developing tank of the developing unit 3 from the toner replenishing unit 3d.
[0032]
Thereafter, the toner replenished in the developing tank is stirred with the carrier by the stirring roller 3c. Then, the developer including the stirred carrier and toner is supplied to the developing roller 3a by the paddle 3b. Then, the toner in the developer supplied to the developing roller 3a adheres to the electrostatic latent image formed on the photosensitive drum 1.
[0033]
Thereafter, the surface of the photosensitive drum 1 developed by the developing unit 3 reaches a position facing the transfer unit 4. Then, the toner corresponding to the image on the photosensitive drum 1 is transferred onto the transfer paper conveyed to the transfer unit 4. At this time, a part of the toner remains on the photosensitive drum 1 as toner not remaining on the transfer paper (remaining toner).
Then, the surface of the photosensitive drum 1 that has passed through the transfer unit 4 reaches the cleaning unit 5. In the cleaning unit 5, the remaining toner on the photosensitive drum 1 is collected by the cleaning blade 5a and the cleaning roller 5b which are in contact with the photosensitive drum 1.
Thereafter, the surface of the photosensitive drum 1 that has passed through the cleaning unit 5 is neutralized by a neutralization unit (not shown), and a series of image forming processes is completed.
[0034]
On the other hand, the residual toner collected by the cleaning unit 5 is transported to the entrance 6a of the toner transport unit 6. Then, the residual toner carried into the inlet 6a is carried toward the outlet 6b by the toner carrying screw of the toner carrying unit 6. After that, the remaining toner is supplied from the outlet 6b of the toner transport unit 6 to the toner classification device 7.
In the toner classification device 7, the recyclable classified toner is supplied to the toner replenishing unit 3 d of the developing unit 3, and the non-recyclable waste toner is discharged to the waste toner container 9 via the waste toner path 8.
[0035]
On the other hand, the transfer paper is fed from a paper feed unit (not shown) toward the transfer paper transport path. Then, the transfer paper that has reached a not-shown registration roller is transported to the transfer unit 4 in order to transfer the toner image formed on the photosensitive drum 1.
Thereafter, the transfer paper to which the toner image has been transferred is conveyed to a fixing unit (not shown), where the image is fixed.
Finally, the transfer paper after fixing passes through a paper discharge unit and is discharged to the outside of the image forming apparatus.
[0036]
Note that the image forming unit that performs the image forming process in the above-described image forming apparatus may be a process cartridge.
That is, two or more individual units among the plurality of individual units constituting the image forming unit are combined as one aggregate, and the aggregate unit is formed so as to be insertable into and removable from the image forming apparatus. For example, the photosensitive drum 1, the charging unit 2, the developing unit 3, the cleaning unit 5, the toner conveying unit 6, and the toner classifying device 7 as a single unit can be configured as one process cartridge.
[0037]
Next, the toner classifying device 7 installed in the above-described image forming apparatus or process cartridge will be described in detail with reference to FIGS.
FIG. 2 is a schematic sectional view showing the toner classification device 7 according to the first embodiment, and FIG. 3 is a schematic perspective view thereof.
[0038]
2 and 3, reference numeral 11 denotes a sieve member for classifying the remaining toner T1 carried in, 11a denotes a mesh portion having meshes formed in a mesh corresponding to the particle size of the toner, and 11b denotes waste toner T3 in the sieve member 11. 11c is a hollow shaft portion of the sieve member 11, 11d is an inlet of the residual toner T1 in the sieve member 11, 12 is a transport screw for guiding the residual toner T1 to the inlet 11d, and 13a is a transport screw 12 provided. The shaft portion of the rotating shaft provided, 13b is the shaft portion of the rotating shaft provided with a brush member, 15 is a brush member as a flexible member, 16 is an inlet side conveying path in which the conveying screw 12 and the like are disposed, 17 Denotes a holding member for accommodating the sieve member 11 and the like.
[0039]
Here, referring to FIGS. 2 and 3, sieve member 11 includes a net portion 11 a, a holding portion made of a resin material holding net portion 11 a, and a shaft portion 11 c integrally formed with the holding portion. And so on. Then, the sieve member 11 rotates in a direction indicated by an arrow in FIG. 3 via a gear (not shown) engaged with the shaft portion 11c.
Referring to FIG. 2, shaft 11c of sieve member 11 is engaged with a bearing provided on holding member 17, and one end of sieve member 11 is rotatably supported. Further, on the inlet 11d side of the sieve member 11, there is provided an opening with which a tubular inlet-side transport path 16 is engaged, and the other end of the sieve member 11 is rotatably supported via a ring member.
[0040]
The mesh portion 11a of the sieve member 11 is formed in a mesh shape using a material such as a metal wire or a resin wire. The mesh number of the mesh portion 11a is, for example, 200 mesh / cm. ² This is set so that the classification toner T2 and the waste toner T3 can be classified.
Referring to FIG. 3, outlet 11b of sieve member 11 is provided with a plurality of openings from which waste toner T3 is discharged.
[0041]
Further, the rotating shafts 13 a and 13 b provided with the brush member 15 and the transport screw 12 are installed on the sieve member 11. Specifically, one ends of the rotating shafts 13 a and 13 b are rotatably supported by the inlet-side transport path 16, and the other end is engaged with the hollow portion of the shaft portion 11 c of the sieve member 11 and is rotatably supported. ing.
[0042]
The conveying screw 12 is provided on the small diameter shaft portion 13a on one side of the rotating shafts 13a and 13b. Then, by the rotation of the transfer screw 12, the residual toner T <b> 1 transferred to the toner classification device is transferred toward the entrance 11 d of the sieve member 11. On the other hand, the brush member 15 is provided spirally in the axial direction on the large diameter shaft portion 13b of the rotating shafts 13a and 13b. That is, the brush member 15 is formed by spirally winding a brush having a predetermined width around the shaft portion 13b.
[0043]
The brush member 15 is, for example, a fur brush made of nylon fiber or the like, and slides on the inner wall of the mesh portion 11a of the sieve member 11, thereby preventing the toner from being clogged on the mesh portion 11a. Further, since the brush member 15 is provided spirally in the axial direction, the brush member 15 conveys the toner from the inlet 11d to the outlet 11b by its rotation.
[0044]
Further, the center of the shaft portion 13a on which the transport screw 12 is installed and the rotation center of the shaft portion 13b on which the brush member 15 is installed do not match. More specifically, the large-diameter shaft portion 13b is eccentric with respect to the small-diameter shaft portion 13a by an eccentric amount G. On the other hand, the rotation center of the shaft portion 11c of the sieve member 11 substantially matches the rotation center of the shaft portion 13a on which the transport screw 12 is installed.
[0045]
Accordingly, the brush member 15 rotates on different rotation axes with respect to the sieve member 11 and the small-diameter shaft portion 13a that rotate on the same rotation axis at different rotation speeds. That is, the brush member 15 conveys the unclassified waste toner T3 toward the outlet 11b while slidingly contacting the inner wall of the sieve member 11 in a non-uniform manner. Focusing on this particular part of the net portion 11a, the contact state of the brush that slides on the part is strongly or weakly contacted (or not contacted) with the rotation cycle of the brush member 15. Or).
[0046]
In this way, the spiral brush member 15 is intentionally slidably and non-uniformly in contact with the inner wall of the mesh portion 11a, so that a large amount of the residual toner T1 is carried into the inside of the sieve member 11 and the predetermined toner conveying force Thus, even if the conveyance of the waste toner T3 cannot catch up, the uneven sliding contact portion serves as an escape route for the toner, and the clogging of the net portion 11a can be prevented.
[0047]
Next, the operation of the thus configured toner classifying apparatus will be described.
Referring to FIGS. 2 and 3, first, the residual toner T1 collected by the above-described cleaning unit 5 is supplied to the entrance-side transport path 16 via the toner transport unit 6. After that, the remaining toner T <b> 1 is guided to the entrance 11 d of the sieve member 11 by the rotation of the transport screw 12. In the sieve member 11, the classifying toner T2 is generated from the residual toner T1 by the rotating mesh portion 11a and the brush member 15 rotating at a different rotation speed from the mesh portion 11a in the mesh portion 11a, The discharge of the toner T3 is performed.
[0048]
More specifically, a part of the residual toner T1 carried in from the entrance 11d passes through the net 11a and is supplied to the developing unit 3 as a recyclable classified toner T2. On the other hand, the paper dust and the toner lump that do not pass through the net portion 11a are conveyed as waste toner T3 toward the outlet 11b by the brush member 15 and collected in the waste toner container 9.
[0049]
As described above, in the first embodiment, the rotation center of the brush member 15 having the toner transporting property and the rotation center of the mesh portion 11a are shifted to make the brush member 15 uneven on the inner wall surface of the mesh portion 11a. In sliding contact. Thus, regardless of the amount of the residual toner T1 carried into the toner classification device 7, the clogging of the net portion 11a is prevented and efficient classification is performed. The stagnation of the waste toner T3 in the classification device 7 can be prevented.
[0050]
In the first embodiment, of the rotating shafts 13a and 13b having the conveying screw 12 and the brush member 15, the shaft portion 13b having the brush member 15 is eccentric, so that the brush member 15 is formed inside the mesh portion 11a. It was made to contact the wall unevenly. On the other hand, by eccentrically rotating the center of rotation of the sieve member 11, the brush member 15 can be brought into nonuniform sliding contact with the inner wall surface of the net portion 11a. In this case, the rotation center of the shaft portion 13b having the brush member 15 coincides with the rotation center of the shaft portion 11b having the transport screw 12. Then, even in these cases, the same effects as in the first embodiment can be obtained.
[0051]
Embodiment 2 FIG.
Embodiment 2 will be described in detail with reference to FIG. FIG. 4 is a schematic front view showing a brush member of the toner classification device according to the second embodiment.
Note that the second embodiment is different from the first embodiment only in the configuration of the brush member. Therefore, in the second embodiment, description and illustration of members common to the first embodiment will be appropriately omitted.
[0052]
In FIG. 4, 13a and 13b are shaft portions of a rotating shaft installed in the toner classification device, 15a is a first brush member spirally formed in the axial direction of the shaft portion 13b, and 15b is a member together with the first brush member 15a. 9 shows a second brush member spirally formed in the axial direction of the shaft portion 13b.
[0053]
Here, the first brush member 15a is formed by winding a brush having a predetermined width spirally around the shaft portion 13b in the axial direction with a gap provided therebetween. The second brush member 15b is obtained by winding a brush having a predetermined width spirally in the axial direction around the shaft portion 13b so as to fill the gap. The bristle height D1 of the first brush member 15a is set to be larger than the bristle height D2 of the second brush member 15b. Therefore, the second brush member 15b comes into sliding contact with the net portion 11a with a smaller force than the first brush member 15a.
[0054]
The transport screw 12 is provided on a part 13a of the rotating shafts 13a and 13b, as in the first embodiment. In the second embodiment, in the rotating shafts 13a and 13b, the rotation center of the shaft portion 13a on which the transport screw 12 is provided, and the shaft on which the first brush member 15a and the second brush member 15b are provided. The center of rotation of the portion 13b matches.
[0055]
The toner classifying apparatus configured as described above operates in the same manner as in the first embodiment.
Specifically, first, the residual toner supplied to the toner classification device is guided to the entrance of the sieve member by the rotation of the transport screw 12. Then, a part of the residual toner carried in from the entrance passes through the mesh part and is supplied to the developing part as classified toner. On the other hand, the waste toner that does not pass through the net portion is conveyed toward the outlet by the first brush member 15a and the second brush member 15b, and is collected in the waste toner container.
[0056]
When focusing on a specific part of the mesh portion, the contact state of the brush that slides on the part is that the first brush member 15a contacts or the second contact member 15b contacts. Become. That is, the two spiral brush members 15a and 15b having different bristle heights D1 and D2 can form an uneven sliding contact state with the inner wall of the net portion.
[0057]
As described above, in the second embodiment, the toner escaping path is secured by the uneven sliding state of the brush members 15a and 15b. Regardless of the amount of residual toner that is carried in, prevent clogging of the mesh part and perform efficient classification, and reliably discharge waste toner to prevent stagnation of waste toner in the toner classification device. Can be.
[0058]
Embodiment 3 FIG.
Embodiment 3 will be described in detail with reference to FIG. FIG. 5 is a schematic front view showing a brush member of the toner classification device according to the third embodiment.
The third embodiment is different from the above embodiments only in the configuration of the brush member.
[0059]
In FIG. 5, 13a is a shaft portion of a rotating shaft on which the conveying screw 12 is installed, 13b is a shaft portion of a rotating shaft on which the brush member 15 is installed, and 15 is a helical gap provided in the toner conveying direction. 4 shows a shaped brush member.
[0060]
Here, the brush member is formed by winding a brush having a predetermined width spirally around the shaft portion 13b in an axial direction with a gap provided therebetween.
The gap formed by the brush member 15 gradually decreases from the inlet side to the outlet side of the toner, and makes a nonuniform sliding contact with the inner wall of the sieve member. That is, the pitch P1 of the brush member 15 on the upstream side of the toner flow path is larger than the pitch P2 on the downstream side.
As a result, the toner conveying force of the brush member 15 is smaller on the downstream side than on the upstream side.
[0061]
Then, the toner classifying device configured as described above operates in the same manner as in each of the above embodiments.
Specifically, first, the residual toner supplied to the toner classification device is guided to the entrance of the sieve member by the rotation of the transport screw 12. Then, a part of the residual toner carried in from the entrance passes through the mesh part and is supplied to the developing part as classified toner. On the other hand, the waste toner that does not pass through the net portion is conveyed toward the outlet by the brush member 15 and collected in the waste toner container.
[0062]
At this time, on the entrance side of the sieve member where the residual toner tends to stagnate, the toner is conveyed toward the exit without stagnation by the large toner conveying force of the brush member 15. On the other hand, at the outlet side of the sieve member, while the toner is being conveyed with a relatively small toner conveying force, the toner is classified over time.
[0063]
As described above, in the third embodiment, the toner conveying force of the brush member 15 is different between the inlet side and the outlet side, so that a large amount of residual toner is carried into the toner classification device. Even if there is, clogging of the net portion due to stagnation of toner on the entrance side can be prevented, and efficient classification can be performed.
[0064]
Embodiment 4 FIG.
Embodiment 4 will be described in detail with reference to FIG. FIG. 6 is a schematic sectional view showing a toner classification device according to the fourth embodiment.
The fourth embodiment differs from the first embodiment in the configuration of the driving unit that drives the rotating shaft and the sieve member and the configuration of the brush member. Therefore, in the fourth embodiment, description and illustration of members common to the first embodiment will be appropriately omitted.
[0065]
In FIG. 6, reference numeral 18 denotes a gear that engages with the shaft portion 11c of the sieve member 11, 20 denotes a gear that engages with the gear 11, 22 denotes a driving unit that drives the sieve member 11, and 23 denotes the transport screw 12 and the brush member 15. A drive unit 25 for driving the rotating shaft 13a is provided, 25 is an optical unit for irradiating the laser beam L in FIG. 1, and 26 is a control unit for controlling the optical unit 25 and the drive units 22 and 23.
[0066]
Here, the control unit 26 changes the number of rotations of the driving unit 23 that rotationally drives the rotating shaft 13 a including the transport screw 12 and the brush member 15. Specifically, the control unit 26 controls the magnitude of the current flowing to the driving unit 23 such as a DC motor to change the rotation speed.
The other drive unit 22 drives the sieve member 11 to rotate at a predetermined rotation speed via the two gears 20 and 18.
[0067]
On the other hand, the optical unit 25 includes a light source such as an LED, and emits the laser beam L described with reference to FIG. Further, the optical unit 25 includes a detection unit that detects the operation rate of the light source, that is, the frequency at which laser light is emitted.
The operating rate of the light source in the optical unit 25 is substantially proportional to the image ratio of the image formed on the photosensitive drum 1 (the ratio of toner occupied per unit area). Further, the amount is substantially proportional to the amount of the residual toner T1 collected from the photosensitive drum 1 and supplied to the toner classification device 7.
[0068]
Then, the toner classifying apparatus and the image forming apparatus configured as described above operate as follows.
First, when the above-described image forming process is performed on the photosensitive drum 1, the detection result of the light source operation rate detected by the detection unit of the optical unit 25 is transferred to the control unit 26. Then, the control section 26 transfers a control signal to the drive section 23 based on the detection result corresponding to the remaining toner amount. Then, the drive unit 23 drives the transport screw 12 and the brush member 15 to rotate based on the control signal.
[0069]
On the other hand, the residual toner T1 supplied to the toner classification device is guided to the inlet 11d of the sieve member 11 by the transport screw 12 rotating at a controlled rotation speed. Then, a part of the residual toner T1 carried in from the entrance 11d passes through the mesh part 11a and is supplied to the developing unit as classified toner T2. On the other hand, the waste toner T3 that does not pass through the net 11a is conveyed toward the outlet 11b by the brush member 15 that rotates at a controlled rotation speed, and is collected in the waste toner container.
[0070]
At this time, the rotation speeds of the brush member 15 and the transport screw 12 are controlled to a relatively low rotation speed when the light source operating rate is low. On the other hand, when the light source operating rate is high, the rotation speeds of the brush member 15 and the transport screw 12 are controlled to be relatively large.
As a result, even when a large amount of the residual toner T1 is carried into the entrance 11d of the sieve member 11, it is detected and the toner conveying force of the brush member 15 is increased.
[0071]
As described above, in the fourth embodiment, since the toner conveying force of the brush member 15 is changed according to the amount of the residual toner T1 carried in from the inlet 11d, a large amount of the residual toner T1 is provided in the toner classification device. Even if is carried in, the mesh 11a can be prevented from being clogged due to stagnation of toner at the entrance 11d, and efficient classification can be performed.
[0072]
In the fourth embodiment, the amount of the residual toner T1 to be carried into the toner classification device is determined by detecting the light source operation rate of the optical unit 25. However, the application of the present invention is not limited to this. For example, a sensor for detecting the remaining toner amount may be provided in the entrance-side transport path 16 of the toner classification device.
[0073]
In the fourth embodiment, two driving units 22 and 23 are provided, and one of the driving units 23 is controlled to change the rotation speed of the brush member 15. On the other hand, a multi-stage gear is installed at the end of the rotating shaft 13a provided with the brush member 15, and the gear ratio is changed by a clutch with a gear group engaged with the multi-stage gear, so that the rotation speed of the brush member 15 is reduced. It can be variable.
[0074]
In each of the above embodiments, the brush member 15 is used as the flexible member that slides on the inner wall of the sieve member 11. However, the present invention is not limited to this, and various flexible members, for example, a polyester film or the like can be used as the flexible member.
[0075]
In each of the above embodiments, the classified toner T2 as the recycled toner is supplied to the toner supply unit 3d of the developing unit 3. However, the present invention is not limited to this. For example, in an image forming apparatus using a one-component developer (toner), the classified toner T2 can be supplied directly from the toner classifying device 7 to the developing unit.
Further, in an image forming apparatus having a toner bank installed at a position distant from the developing unit, the classified toner T2 can be supplied from the toner classifying device 7 to the toner bank.
[0076]
In each of the above-described embodiments, the remaining toner T1 on the photosensitive drum 1 is supplied to the toner classification device 7 to perform classification. On the other hand, in the image forming apparatus that collects the residual toner on the transfer unit constituted by the transfer belt, the residual toner can be supplied to the toner classifying device 7 as in the above embodiments. .
[0077]
Further, in each of the above embodiments, the toner classifying device 7 is installed in the image forming apparatus or the process cartridge. However, the toner classifying apparatus of the present invention is not limited to this, and may be, for example, an apparatus used in a toner mass removing step in a toner manufacturing step.
[0078]
It should be noted that the present invention is not limited to the above-described embodiments, and it is apparent that the embodiments can be appropriately modified in addition to those suggested in the embodiments within the scope of the technical idea of the present invention. It is. Further, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiment, and can be set to numbers, positions, shapes, and the like suitable for carrying out the present invention.
In the description in the specification, “toner not classified” or “waste toner” is defined to include, in a strict sense, foreign substances such as paper powder which are not toner.
[0079]
【The invention's effect】
Since the present invention is configured as described above, regardless of the amount of toner carried into the apparatus, it prevents clogging and performs efficient classification, and reliably discharges unclassified toner to the outside of the apparatus. Thus, it is possible to provide a toner classifying apparatus which does not cause a problem such as locking, and a process cartridge and an image forming apparatus having the same.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing an image forming apparatus according to Embodiment 1 of the present invention.
FIG. 2 is a schematic cross-sectional view illustrating a toner classification device in the image forming apparatus of FIG.
FIG. 3 is a schematic perspective view showing the toner classification device of FIG.
FIG. 4 is a schematic front view showing a toner classification device according to Embodiment 2 of the present invention.
FIG. 5 is a schematic front view showing a toner classification device according to Embodiment 3 of the present invention.
FIG. 6 is a schematic sectional view showing a toner classification device according to Embodiment 4 of the present invention.
[Explanation of symbols]
Reference Signs List 1 photosensitive drum (image carrier), 2 charging unit, 3 developing unit, 4 transfer unit, 5 cleaning unit, 6 toner transport unit, 7 toner classifier, 8 waste toner path, 9 waste toner container, 11 sieve member, 11a mesh portion, 11b outlet, 11c shaft portion, 11d inlet, 12 transport screw, 13a, 13b shaft portion (rotating shaft), 15 brush member (flexible member), 15a first brush member, 15b second brush member, Reference Signs List 16 Inlet side conveyance path, 17 holding member, 18, 20 gear, 22, 23 drive unit, 25 optical unit, 26 control unit, T1 residual toner (recovered toner), T2 classification toner, T3 waste toner, G eccentricity, D1 , D2 Hair height, P1, P2 pitch (gap).

Claims (13)

A sieve member for classifying the toner carried in from the inlet until it is carried out to the outlet,
And a flexible member that conveys the non-classified toner among the toner toward the outlet and slidably contacts the inner wall of the sieve member in a non-uniform manner. The sieve member is cylindrical and rotatably formed,
The flexible member is formed so as to be rotatable in the same or opposite direction as the rotation direction of the sieve member,
The toner classification device according to claim 1, wherein the rotation center of the sieve member and the rotation center of the flexible member do not match. A rotating shaft having a shaft provided with a conveying screw for guiding the toner toward the inlet of the sieve member, and a shaft provided with the flexible member;
3. The toner classification device according to claim 1, wherein the rotation center of the shaft provided with the transport screw and the rotation center of the shaft provided with the flexible member do not match. 4. 4. The toner classification device according to claim 1, wherein the flexible member is a brush member spirally formed in a direction in which the toner is conveyed. 5. The flexible member is formed with a first brush member provided with a gap spirally with respect to the toner conveyance direction, and is formed with a spiral shape so as to partially or entirely fill the gap. The toner classification device according to any one of claims 1 to 4, further comprising a second brush member having a bristle height smaller than that of the first brush member. The flexible member includes a brush member formed with a gap in a spiral shape with respect to the toner conveyance direction,
The toner classification device according to any one of claims 1 to 4, wherein the gap on the inlet side is formed to be larger than the gap on the outlet side. A sieve member for classifying the toner carried in from the inlet until it is carried out to the outlet,
A flexible member that slidably contacts the inner wall of the sieve member while conveying the toner that is not classified among the toner toward the outlet,
The toner classifying device according to claim 1, wherein a conveying force of the toner by the flexible member is changed according to an amount of the toner carried in from the entrance. The sieve member is cylindrical and rotatably formed,
The flexible member is a brush member spirally formed with respect to the toner conveyance direction, and is formed so as to be rotatable in the same direction as the rotation direction of the sieve member or in the opposite direction.
The toner classification device according to claim 7, wherein the number of rotations of the flexible member is changed in accordance with the amount of toner carried in from the entrance. A process cartridge comprising the toner classification device according to claim 1. An image carrier;
A developing unit that supplies toner on the image carrier;
A cleaning unit that collects residual toner on the image carrier,
The residual toner collected by the cleaning unit is conveyed toward the entrance of the toner classification device, and the toner classified by the sieve member of the toner classification device is supplied to the developing unit. The process cartridge according to claim 9, wherein: An image forming apparatus comprising the toner classification device according to claim 1. An image carrier;
A developing unit that supplies toner on the image carrier;
A cleaning unit that collects residual toner on the image carrier,
The residual toner collected by the cleaning unit is conveyed toward the entrance of the toner classification device, and the toner classified by the sieve member of the toner classification device is supplied to the developing unit. The image forming apparatus according to claim 11, wherein A detection unit that detects an operation rate of a light source that emits light toward the image carrier,
A drive unit that drives the flexible member while changing the rotation speed thereof,
The image forming apparatus according to claim 12, further comprising: a control unit that controls the driving unit according to a detection result of the detection unit.

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