This application is based on and claims priority pursuant to 35 U.S.C. §119 to Japanese Patent Application No. 2011-192183, filed on Sep. 3, 2011, the entire contents of which are incorporated herein by reference.
1. Field
The exemplary embodiments described herein relate to a paper edge cleaner for an image forming apparatus such as a copier, a printer, a facsimile machine, a printer, etc. and to an image forming apparatus that has a paper edge cleaner.
2. Description of the Related Art
An electrophotographic image-forming apparatus makes a copy or a print by transferring a toner image to paper, and fixes the toner image on the paper using heat and pressure. Many types of paper can be used. Moreover, a high image quality and a uniform glossiness are required for a full-color image, such as a photograph or a computer graphics image.
Uniform glossiness is prevented by a cutting burr that is made on a paper edge when the paper is cut, because the burr damages a fixing member in a fixing unit. When a plurality of same size papers are continuously used, the cutting burr on the edge of the paper contacts a same place on the fixing member and damages a surface on the fixing member at a fixing nip. Such damage causes an uneven glossiness line and a poor image. To solve this problem, applications JPH10-218459 and JP2005-179041 describe crushing the burr at the paper edge by a strong pressure provided by a pair of rollers.
However, the above-described rollers for crushing the burr have the following problems. Such rollers need a high pressure to crush the cutting burr on the paper. Therefore, such a roller system requires a big roller and a strong frame to maintain the high pressure, along with a strong driving source. This makes the apparatus bigger. Moreover, in this system, an impulsive sound occurs when the paper passes through the rollers.
An exemplary embodiment provides a paper edge cleaner, comprising: a paper guide; a paper-carrying roller to transport a paper along the paper guide; a first grinder to grind both sides of the paper parallel to a direction of paper movement at a first surface; and a first support to support the paper when contacted by the first grinder.
Another exemplary embodiment provides an image forming method, comprising: feeding paper from a paper feeding unit; transporting the paper along a paper guide; grinding, using a grinder, both sides of the paper parallel to a direction of paper movement at a first surface, wherein the grinding step includes supporting the paper when contacted by the grinder; and forming an image on the paper grinded in the grinding step.
Another exemplary embodiment provides an image forming apparatus, comprising: a paper feeder to feed paper; an image forming device to form an image on the paper; and a paper edge cleaner provided between the paper feeder and the image forming device, the paper edge cleaner including a paper guide; a paper-carrying roller to transport the paper along the paper guide; a first grinder to grind both sides of the paper parallel to a direction of paper movement at a first surface; and a first support to support the paper when contacted by the first grinder.
A more complete appreciation of the exemplary embodiments described herein and many of the attendant advantages thereof will be more readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
The image forming apparatus has a internal paper-eject structure that includes output paper tray 2 provided between an image scanner 5 and an image forming unit in a machine body 1. An openable and closable auto-document feeder (ADF) 3 is provided on the machine body 1. ADF 3 includes a document-setting board 3a and a document-carrying belt 3b. The image forming apparatus includes a contact glass 4 under the ADF.
The image scanner 5 under the contact glass 4 has an optical system including a light source and an imaging element. A document is set on the contact glass by a user or is fed to the contact glass by the ADF 3, where an image on the document is read by the scanner. The image forming apparatus includes an intermediate transfer belt 9 in a middle of the machine body 1, as shown in
Each image forming unit includes a charger to charge a surface of each photoconductor 6Y, 6C, 6M, and 6K, and developing units 7Y, 7C, 7M, and 7K to develop each electrostatic latent image on the surface of each photoconductor that is formed by a writing unit. Primary transfer rollers 8Y, 8C, 8M, and 8K face each photoconductor 6Y, 6C, 6M, and 6K across the intermediate transfer belt 9.
There are two feeding paper trays 15 in a lower part of the machine body 1 that accommodate paper P as a recording medium. Further, there are corresponding paper feeding rollers 17 as paper feeding means to feed paper P from each paper feeding tray 15, several pairs of carrying rollers 18, and a registration roller 11 in the machine body 1. Further, the image forming apparatus includes a secondary transfer roller 10 contacting the intermediate transfer roller 9, and a fixing unit 12 over the secondary transfer roller 10.
The thin solid line in
A paper edge cleaner 20 is provided between the registration roller 11 and the secondary transfer roller 10 in the paper carrying path 13. Details of the paper edge cleaner are described below. Toner bottles 16Y, 16C, 16M, and 16K supply color toner to each developing unit 7Y, 7C, 7M, and 7K under the output paper tray 2 in the machine body 1.
The image forming apparatus 100 prints an image on paper P based on original document image data read by the image scanner 5 or print data sent from a host apparatus, such as a personal computer connected to a network. Each color toner image is formed on each respective photoconductor 6Y, 6C, 6M, and 6K in each corresponding image forming unit. Each color toner image is transferred to the intermediate transfer belt 9 sequentially and superimposed thereon. Then, a full color toner image is formed on the intermediate transfer belt. The full color toner image is carried to the secondary transfer unit in which the secondary transfer roller 10 faces the intermediate transfer belt 9.
Further, paper P in one of feeding paper trays 15 is carried to the registration roller 11 by the paper feeding roller 17 and pairs of carrying rollers 18. The paper is then sent by the registration roller 11 to meet the transferred toner image on the intermediate transfer belt 9 at the secondary transfer roller. After a paper edge cleaner removes cutting burr from the paper, the toner image on the intermediate transfer belt 9 is transferred to the paper P by the secondary transfer roller 10.
The paper P with the transferred toner image is carried to a fixing unit 12. The toner image is fixed by heat and pressure in the fixing unit 12. Thus, the paper with the fixed toner image is outputted to the output paper tray 2 by the pair of outputting paper rollers 14. When another toner image is formed on the other side of the paper, the paper with the fixed toner image on one side is carried to the paper path 19 for double-face printing, is held by the registration roller 11, and another toner image is transferred to the other side of the paper. The toner image is fixed in the fixing unit 12 and is output to the output paper tray 2.
Details of a first embodiment of the paper edge cleaner 20 between the registration roller 11 and the secondary transfer roller 10 on the paper carrying path 13 is explained below with reference to
The first embodiment is explained with reference to
In the following explanation, “upstream” means upstream in the paper P movement, e.g., the left side in
The pair of carrying rollers 41 includes two carrying rollers 41 a fixed at an interval on the same axis 41c shown in
The pair of carrying rollers 42 include two carrying rollers 42a fixed at an interval on the same axis 42c shown in
Rails 30 shown in
A pair of elastic grinding plates 32 as a paper edge cleaner are provided in the paper carrying path 13 inside of the base units 31. Each elastic grinding plate has a SUS plate spring 32a attached to a grinding sheet 32b as a lapping film. To avoid getting the tip of the paper hung up on the elastic grinding plates 32, an upstream side of the plate spring 32a has a beveled form, as shown in
Facing members 33 are provided in the rails 30 under the pairs of guide plates 21, 22 to face each base unit 31 at a predetermined distance. A pair of supporting rollers is supported rotatable between a base unit 31 and a facing member 33. Each supporting roller supports the paper P pressed against the elastic grinding plate 32 to keep the paper P in the paper carrying path 13. The supporting rollers have an elastic layer. The supporting rollers are supported by a plastic axis, and are driven by the paper P to rotate.
In the first embodiment, a controller receives print information, identifies a width and type of the paper, drives base units 31 symmetrically along the rails 30 in a direction of the arrow B shown in
The registration roller 11 shown in
After a tip of the paper P is pinched by the pair of carrying rollers 42, the paper P is carried in a direction of the arrow A by the pair of carrying rollers 42. When the paper type identified by the controller does not need grinding of the edge of the paper, cams 51,52 shown in
Because the grinding sheets 32b on the elastic grinding plates 32 grind both sides of the paper carried to the secondary transfer, the cutting burr of the paper can be removed. Therefore, in the image forming apparatus 100 having this paper edge cleaner, because the side of the paper does not cause damage to a surface of the fixing member, a poor image, e.g., having an uneven glossiness line, is prevented.
In the first embodiment, a tip of the paper does not get hung up on the elastic grinding plates 32 because the upstream side of the plate spring 32a has a beveled form that increases in width gradually from upstream to downstream, and bends down gradually to contact the paper carrying path. However, it is acceptable that the plate spring 32a at least bends down gradually to contact the paper carrying path, without having the beveled form.
A second embodiment of the paper edge cleaner is explained with reference to
A difference between the first embodiment and the second embodiment is the paper edge cleaners that are set inside of the base units 31. A pair of grinding rollers 36 serving as the paper edge cleaner is attached as shown in
Each grinding roller 36 has a conical shape whose top is located in the paper carrying path 13, and whose bottom is supported rotatably at an axis 36b in each base unit 31. A conical surface of the grinding rollers is covered by fine abrasives 36a. Both sides of the paper carried along the paper path 13 are pinched by the pair of grinding rollers 36 and the supporting rollers 34 and are grinded.
In the second embodiment, a controller receives print information, identifies a width and type of the paper, drives base units 31 symmetrically along the rails 30 in a direction of the arrow B shown in
The paper P is carried by the pair of paper carrying rollers 41 in a direction of the arrow A shown in
It is preferable that the grinding rollers 36 have an amount of rotational load and skid on the paper P to grind it. The second embodiment has the same effect as the first embodiment. An alternative embodiment for thick papers and paper that does not need grinding can be similarly provided.
A third embodiment of the paper edge cleaner is explained with reference to
A difference between the first embodiment and the third embodiment is two pairs of elastic grinding plates 32X, 32Y along the paper carrying path 13 in the large space 24 between the upstream pair of guide plates 21 and the downstream pair of guide plates 22, as shown in
A pair of elastic grinding plates 32X is provided on one side of the paper carrying path 13 inside of the base units 31A facing each other to contact with a surface on the one side of the paper. Another pair of elastic grinding plates 32Y is provided on an opposite side of the paper carrying path 13 inside of the base units 31B, facing each other to contact with another surface on the opposite side of the paper. Further, there is a pair of short guide plates 23 in a middle of the space 24, as shown in
In the third embodiment, a controller receives print information, identifies a width and type of the paper, drives base units 31A, 31B symmetrically along the rails 30 in a direction of the arrow B shown in
The paper P is carried by the pair of paper carrying rollers 41 in a direction of the arrow A shown in
The exemplary paper edge cleaner according to the third embodiment can remove cutting burr on surfaces on both sides of the paper because it grinds the paper surfaces in the paper carrying path 13. Thus, this embodiment has the same effect as the other embodiments described above. The above modifications for the paper type also apply to this embodiment. Either the elastic grinding plates 32X or the elastic grinding plates 32Y or both can be replaced by the grinding rollers similar to the grinding rollers 36 in the second embodiment shown in
A fourth embodiment of the paper edge cleaner is explained with reference to
A difference between the first embodiment and the fourth embodiment is two pairs of the elastic grinding plates 32R, 32F along the paper carrying path 13 in the large space 24 between the upstream pair of guide plates 21 and the downstream pair of guide plates 22, as shown in
Rough grinding sheets 32c are attached to the plate springs 32a of the upstream elastic grinding plates 32R. Fine grinding sheets 32d are attached to the plate springs 32a of the downstream elastic grinding plates 32F. Further, there is a pair of short guide plates 23 in the middle of the space 24, as shown in
In the fourth embodiment, a controller receives print information, identifies a width and type of the paper, drives base units 31A, 31B symmetrically along the rails 30 in a direction of the arrow B shown in
The paper P is carried by the pair of paper carrying rollers 41 in the direction of the arrow A shown in
Next, the paper P is carried to the grinding plate 32F. Both sides of the paper P are pinched by the elastic grinding plates 32F and the supporting rollers 34 and moved between them. The edges on both sides of the paper P are grinded by the fine grinding sheet 32d. Therefore, smaller cutting burrs on the edges are removed. Thus, the edges on both sides of the paper P become smooth.
In this embodiment, larger cutting burrs can be removed by the rough grinding sheets 32c of the upstream elastic grinding plates 32R. Further, smaller cutting burrs can be removed by the fine grinding sheets 32d of the downstream elastic grinding plates 32F. Thus, the paper edges become smoother.
The effect of this embodiment is similar to the effect of the other embodiments described above. The above modifications for the paper type also apply to this embodiment. Further, either the elastic grinding plates 32R or the elastic grinding plates 32F or both can be replaced by the grinding rollers such as the grinding rollers 36 used in the second embodiment, as shown in
It is preferable that some pairs of the paper edge cleaner are provided in the direction of the paper movement. Especially, it is preferable that each paper edge cleaner have a different surface roughness in the direction of the paper movement. Further, it is more preferable that downstream paper edge cleaners have finer grinding surfaces.
A fifth embodiment of the paper edge cleaner is explained with reference to
A difference between the first embodiment and the fifth embodiment is pairs of rotatable paper dust-cleaning brushes 37 facing each other across the paper carrying path 13 inside of the base unit 31 as a paper dust cleaner.
The paper dust-cleaning brushes are provided inside of the base unit 31 downstream from the elastic grinding plates 32 including the plate springs 32a and the grinding sheets 32b. Air suction ports 38 connected with an air suction pump are provided near bases of the paper dust-cleaning brushes to suction paper dust present in the paper dust-cleaning brushes.
In the fifth embodiment, the grinding sheets 32b of the elastic grinding plates 32 grind edges on both sides of the paper carried along the paper carrying path 13, and remove cutting burr in a manner similar to the first embodiment. The paper dust cleaning brushes 37 contact both surfaces at both edges of the paper P and clean paper dust residing there. The paper dust is suctioned to the air suction port 38 by the air suction pump. As a result, skidding of the paper movement and contamination by paper dust are prevented.
The exemplary paper edge cleaner according to this embodiment has paper dust cleaning brushes 37 downstream of the paper movement from the base units 31 of the first embodiment. Similarly, the paper dust-cleaning brush can be provided downstream of the paper movement from the base units 31 of the second to fourth embodiments. The paper dust-cleaning brushes may be provided not only in the base units 31, but also in another part independently downstream of the paper movement from the base units attached to the paper edge cleaners.
The image forming apparatus 100 has a paper edge cleaner 20 in various embodiments between the registration roller 11 and the secondary transfer roller 10 in the paper carrying path 13. However, the location of the paper edge cleaner is not limited to this. The paper edge cleaner 20 can be set anywhere between the paper feeding device to feed the paper (paper feeding roller 17 in
The image forming apparatus is not limited to a tandem-type, intermediate-transfer, full-color apparatus. Other embodiments in other color printers can include a direct transfer system or another intermediate transfer system, black and white printers, copiers or fax machines including a scanner, and one of the above printers and multi-functional digital machines.
Numerous additional modifications and variations of the disclosed exemplary embodiments are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the embodiments may be practiced otherwise than as specifically described herein.
Number | Date | Country | Kind |
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2011-192183 | Sep 2011 | JP | national |