JP2004252086A - Transfer conveying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately ensure positioning among a driving roller, a cleaning roller and cleaning blades and to upgrade cleaning quality, by supporting such principal components of a cleaning section by a positioning lateral plate and attaching the lateral plate to transfer casing molded from resin. <P>SOLUTION: A belt driving roller 21, a cleaning roller 25 and cleaning blades 26, 28 are attached to a positioning lateral plate 33 being separated from the transfer casing 35 made of resin, and this lateral plate 33 is attached to transfer casing 35 made of resin. Thus, members to which relative positional accuracy is important can be accurately attached, and the following problem is dissolved: cleaning blades and a transfer belt or a cleaning roller to be accurately positioned are liable to fluctuate in accuracy, whereby satisfactory quality cannot be ensured. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
[Industrial applications]
The present invention relates to an image forming apparatus such as a copying machine, a facsimile, and a printer, and more particularly, moves a transfer position facing an image carrier that carries a toner image while forming a nip with the image carrier. The present invention relates to an image forming apparatus including a transfer belt and employing a transfer device that electrostatically transfers a toner image on an image carrier to the transfer belt.
[0002]
[Prior art]
Generally, a casing of a transfer device, a so-called casing, is often made of an insulator (hereinafter simply referred to as a resin) such as a synthetic resin. This has a complicated shape, and is not suitable for manufacturing with a metal material such as a sheet metal. In addition, since a high-voltage circuit is operated in a transfer process, there is a danger of a leak or the like, and it may be difficult to handle without an insulator. In general, the casing is usually provided with a shape for holding the built-in component, which also serves to simplify the component configuration. However, with the recent improvement in image quality, the toner particle size has become smaller, and the quality required for cleaning has also become higher.
[0003]
Although the cleaning roller in this configuration also follows this flow, there is a problem that components cannot be mounted with high accuracy when positioned in the resin casing. In other words, the resin component has to be compromised to some extent in the molding dimensional accuracy, is likely to contract due to heat (dimensional variation), is insufficient in rigidity, and is liable to be deformed such as warpage. Therefore, the accuracy of the cleaning blade and the transfer belt or the cleaning roller, which should be positioned with high precision, tends to vary, and sufficient quality may not be secured. In order to solve the problem, there is an example in which a plurality of cleaning blades are devised so as to be attached based on one point of a resin casing. (See, for example, Patent Document 1).
[0004]
[Patent Document 1]
JP-A-2002-328534 (page 5, FIG. 5)
[0005]
[Problems to be solved by the invention]
Since the relative positional relationship between the cleaning blade and the transfer belt or the cleaning roller is important for the cleaning means, it is still insufficient to increase the accuracy of only the position of the cleaning blade.
In the present invention, the transfer roller is formed by providing a positioning side plate at both ends of the main part of the cleaning unit with respect to the transfer casing molded of resin, supporting the positioning side plate, and assembling the side plate to the transfer casing. It is another object of the present invention to accurately maintain the positioning between the respective components of the cleaning roller and the cleaning blades and improve the cleaning quality.
[0006]
[Means for Solving the Problems]
According to the first aspect of the present invention, there is provided a transfer / conveying apparatus which is mounted on an image forming apparatus, and transfers a visible image on an image carrier of the image forming apparatus onto a recording material and conveys the recording material. A transfer belt stretched between a drive roller and a driven roller, a cleaning unit for cleaning the transfer belt, and a positioning side plate fixed to the housing; The cleaning unit is positioned and fixed to the positioning side plate.
[0007]
According to a second aspect of the present invention, in the transfer / transport apparatus according to the first aspect, the cleaning unit electrically connects the first cleaning blade abutted on the transfer belt and the transfer belt abutted on the transfer belt. And a second cleaning blade which is in contact with the cleaning roller.
According to a third aspect of the present invention, in the transfer conveyance device according to the second aspect, the first cleaning blade is fixed so as to abut on the transfer belt using only elastic deformation of the blade. The second cleaning blade is configured to be pressed against the cleaning roller by a pressing member such as a spring.
[0008]
According to a fourth aspect of the present invention, in the transfer / transport apparatus according to any one of the first to third aspects, the positioning side plate is a side plate formed of a sheet metal member.
According to a fifth aspect of the present invention, in the transfer / transport apparatus according to any one of the first to fourth aspects, the positioning side plate is positioned on the housing at a bearing position of the drive roller.
According to a sixth aspect of the present invention, in the transfer / transport apparatus according to any one of the first to fourth aspects, the positioning side plate is attached to a member on the image forming apparatus main body side by a jig simulating the image forming apparatus. It is characterized by being positioned.
According to a seventh aspect of the present invention, there is provided an image forming apparatus using the transfer transport device according to any one of the first to sixth aspects.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described according to an embodiment in which the present invention is applied to a digital copying machine (hereinafter, referred to as a copying machine) which is an image forming apparatus.
FIG. 1 is a schematic configuration diagram of a copying machine according to an embodiment of the present invention.
In the drawing, reference numeral 1 denotes an automatic document feeder (ARDF), 2 denotes a contact glass as a document table, 3 denotes a light source, 4, 5, and 6 mirrors, and 7 denotes an image forming lens and a CCD including an image sensor. An image optical system, 8 is a writing unit, 9 is a rotary polygon mirror for scanning, 10 is a scanning optical system such as an fθ lens, 11, 12, and 13 are mirrors, 14 is a photosensitive drum as an image carrier, and 15 is a charged drum. Reference numeral 16 denotes a developing device, 100 denotes a transfer device using a transfer / conveyance belt, 33 denotes a cleaning device, 30 denotes a fixing device, and 20 denotes a paper feed unit.
[0010]
First, the configuration and operation of the entire copying machine will be described with reference to FIG.
The document reading unit forms an image of the document on the contact glass 2 on the CCD by the light source 3, the mirrors 4, 5, 6 and the image forming optical system 7, reads the image in units of pixels, and converts it into a digitized image signal. . This image signal is sent to the writing unit 8 or stored in a pixel memory (not shown). The writing unit 8 scans a laser beam from a laser diode (not shown) according to the read image signal, and writes an image on the photosensitive drum 14 via the mirrors 11 to 13.
[0011]
After the photosensitive drum 14 is uniformly charged by the charging device 15, the photosensitive drum 14 is irradiated with the laser beam from the writing unit 8 to form an electrostatic latent image. This electrostatic latent image is developed by the developing device 16 to form a toner image as a visible image. On the other hand, the transfer paper is fed from the paper feeding unit 20 and is conveyed to a transfer position where the photosensitive drum 14 and the transfer device 100 are opposed to each other. The transfer device 100 electrostatically transfers the toner image formed on the photosensitive drum 14 to a transfer member. The transfer device 100 will be described with reference to FIG.
[0012]
Next, the transfer paper is sent to the fixing device 30, and an image is obtained by fixing the toner on the transfer body. On the other hand, the residual toner on the photosensitive drum 14 is removed by the cleaning device 33. Although not shown in the copying machine of the present embodiment, a duplex unit may be installed between the transfer device 100 and the paper feeding unit 20. When the duplex unit is provided, it is possible to form an image on both sides of the sheet by reversing the sheet printed on one side and re-feeding the sheet.
[0013]
FIG. 2 is a schematic side view of the transfer device according to the present invention.
In the figure, reference numeral 21 denotes a driving roller, 22 denotes a driven roller, 23 denotes a bias roller, 24 denotes a transfer belt, 25 denotes a cleaning roller, 26 denotes a first cleaning blade, 28 denotes a second cleaning blade, and 33 denotes a positioning plate. , 34 indicate a waste toner conveying screw, and 35 indicates a transfer casing.
The transfer process operation of the present apparatus is basically the same as a normally used process as in Patent Document 1. The different points of the present invention are described below.
[0014]
The transfer casing 35 forming the outer shape of the normal transfer unit is made of an insulator such as a resin. However, as described above, resin products may not be able to guarantee sufficient quality. Also in the present invention, the outer shape and the like of the transfer casing 35 are made of resin, but the main parts of the cleaning unit are supported at both ends by positioning side plates 33 separate from the transfer casing 35, and this side plate is It is configured to be assembled to the transfer casing 35.
[0015]
The driving roller 21, the cleaning roller 25, the first cleaning blade 26, and the second cleaning blade 28 are positioned on the positioning side plate 33, and the positioning between the respective components is ensured with the accuracy of the positioning side plate 33 itself. It has become so. The material of the positioning side plate 33 is preferably a metal material.
However, depending on the type of the resin, if the molding size is not large, some accuracy can be ensured, so that it can be used as a positioning side plate.
[0016]
3 to 5 show detailed views of the transfer device. 3 is a sectional view, FIG. 4 is a top view, and FIG. 5 is an exploded perspective view.
In these figures, reference numerals 27 and 29 denote cleaning holders, 30 denotes a support plate, 31 denotes a spring, 32 denotes a pin, 36 denotes a bearing, 37 denotes a fulcrum pin, 38 denotes a reference boss, 39 denotes a drive shaft hole, and 40 denotes a cleaning roller. Each shows a shaft hole.
[0017]
The first cleaning blade 26 is hot-melt bonded to the cleaning holder 27 and the second cleaning blade 28 is hot-melt bonded to the cleaning holder 29, and are mounted on the main body. At the ends of the cleaning holders 27 and 29, a mounting reference hole and a screw fixing hole are provided.
The positioning side plates 33 are formed as a pair, and are fixed to the inner wall of the transfer casing 35 with screws or the like.
[0018]
The first cleaning blade 26 has a mounting reference hole of the holder fitted to a blade mounting reference boss 38 provided at a cut-and-bent portion of the positioning side plate 33, and is fixed with screws. The shaft of the drive roller 21 is fitted into and supported by a drive shaft hole 39 provided in the positioning side plate 33 via a bearing (not shown). With this configuration, the first cleaning blade 26 and the driving roller 21 can be assembled with high precision via the positioning side plate 33. The first cleaning blade 26 comes into contact with the transfer belt 24 in a predetermined elastically deformed state, that is, at a normal force N ₁ and a contact angle β ₁ to perform cleaning.
[0019]
On the other hand, the second cleaning blade 28 is fixed to the support plate 30 by fitting the reference boss similarly to the above, and is rotatably supported by a fulcrum pin 37 caulked to the positioning side plate 33. The cleaning roller 25 is also supported via a bearing 36 in a cleaning roller shaft hole 40 provided in the positioning side plate 33. In order to apply a bias voltage to the cleaning roller 25, the bearing 36 uses an insulating material such as a resin to prevent leakage to the positioning side plate 33. The assembling precision is configured such that good quality can be obtained as described above.
Further, in this configuration, since the nip deviation between the cleaning roller 25 and the transfer belt 24 can be expected to be minimized, a difference in the left and right circumferential lengths of the transfer belt due to the nip difference does not occur, and the cause of the belt deviation does not occur. .
[0020]
Above, the second cleaning blade 28 is pressurized by the spring 31 from the lower surface of the support plate 30, it is brought into contact with the contact angle beta ₂ in the cleaning roller 25. With this configuration, the followability of the first blade with respect to the blade contact is further improved, and the first blade is provided with a performance capable of dealing with even small-diameter particles. With the first blade 26, relatively large particles such as paper dust are scraped off, and with the second blade, finer particles such as small particle size toner can be cleaned, and the function is differentiated. In addition, the configuration is such that the cleaning performance is ensured while the contact pressure is reduced, and high durability is aimed at.
[0021]
The spring 31 is assembled so that a pressure is applied between the support plate 30 and the pin 32 by using a pin 32 caulked at a cut and bent portion provided on the positioning side plate 33 as a guide. In this configuration, since the blade 28 is almost directly pressed through the support plate 30, the responsivity is higher than that of a conventional method in which a torsion spring is provided on the blade rotation shaft (corresponding to the fulcrum pin 37) and pressed. excellent, minimize micro-vibration caused by friction of the contact blades 28, the adhesion to the cleaning roller 25, i.e., increasing the contact force N _2, enhanced cleaning quality.
[0022]
In addition, since the cleaning roller 25, the support plate 30 (blade 28), and the pin 32 are positioned on the positioning side plate 33, the mounting length of the spring can be accurately controlled, and therefore, the contact condition (normal force N, contact force The angle β) can be managed with high accuracy.
The springs 31 are arranged symmetrically to each other and are configured to be pressurized at both ends, so that the contact pressure deviation due to the deflection of the support plate 30 and the cleaning holder 29 can be minimized, and good cleaning performance over the entire width is achieved. It is supposed to be secured.
[0023]
The transfer casing 35 is attached to the main body of the image forming apparatus according to a predetermined attachment position. There are two methods. One of the methods is a method based on the mounting hole of the drive roller 21 of the transfer casing 35 as a reference. A bearing (not shown) for the drive roller 21 is fitted into the mounting hole, and a drive shaft hole 39 of the positioning side plate 33 is fitted into the bearing, and the mounting is fixed to the transfer casing 35 by a screw hole provided in the positioning side plate 33. .
[0024]
The other one is that when the positioning side plate 33 is attached to the transfer casing 35, first, the transfer casing 35 is attached to a virtual main body as a jig so that the positioning side plate 33 is at a predetermined position with respect to the jig. After positioning, it is fixed to the transfer casing 35. Therefore, even if the transfer casing 35 is deformed as a finished product, if it is within the tolerance, the cleaning unit can maintain not only the mutual accuracy but also high accuracy for members other than the transfer conveyance device. Can be maintained.
[0025]
In the present invention, the cleaning blades 26 and 28 and the cleaning holders 27 and 29 are made of the same component, and can be used for both the first and second types only by changing the mounting direction. Then, the cleaning blade can be made up of one kind of component, and it is possible to prevent replacement mistakes at the time of regular replacement. Furthermore, by setting the contact conditions (N: normal force, β: contact angle) to be the same, the degree of deterioration of parts can be managed to the same degree, the replacement interval can be made at the same time, and the number of service maintenances can be reduced. It has the effect of being able to do things.
[0026]
6 and 7 are diagrams showing the configuration of an image forming apparatus to which the present invention can be applied.
Until now, the present invention has been described by applying the present invention to the image forming apparatus having a one-drum configuration shown in FIG. 1, but the present invention is not limited to this.
FIG. 6 is a diagram illustrating an example of a direct-type color image forming apparatus of a plurality of drums (so-called multi-drum) type, and FIG. As shown in these drawings, in an image forming apparatus having a structure in which a cleaning unit is provided around a driving roller of a transfer belt, the present invention is applicable to both a direct type and an indirect type, and a single drum type and a multi-drum type. Can be applied as it is.
[0027]
【The invention's effect】
According to the present invention, even if a synthetic resin molded product is used for the transfer casing, the cleaning means can be accurately assembled to the drive roller because the separate positioning side plate is used.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a copying machine according to an embodiment of the present invention.
FIG. 2 is a schematic side view of a transfer device according to the present invention.
FIG. 3 is a sectional view of a transfer device.
FIG. 4 is a top view of the transfer device.
FIG. 5 is an exploded perspective view of the transfer device.
FIG. 6 is a diagram illustrating a configuration of an image forming apparatus to which the present invention can be applied.
FIG. 7 is a diagram illustrating a configuration of an image forming apparatus to which the present invention can be applied.
[Explanation of symbols]
Reference numeral 21 Drive roller 22 Follower roller 23 Bias roller 24 Transfer belt 25 Cleaning roller 26 First cleaning blade 27 Cleaning holder 28 Second cleaning blade 29 Cleaning holder 30 Support plate 31 Spring 32 Pin 33 Positioning side plate 34 Waste toner transport screw 35 Transfer casing 36 Bearing 37 Support pin 38 Reference boss 39 Drive shaft hole 40 Cleaning roller shaft hole

Claims (7)

A transfer / conveyance device mounted on an image forming apparatus, which transfers a visible image on an image carrier of the image forming apparatus onto a recording material and conveys the recording material, comprising a housing, a driving roller and a driven roller. A transfer belt having a transfer belt stretched therebetween, a cleaning unit for cleaning the transfer belt, and a positioning side plate fixed to the housing, wherein the driving roller and the cleaning unit are positioned relative to each other; A transfer / conveying device which is positioned and fixed to a side plate. 2. The transfer conveyance device according to claim 1, wherein the cleaning unit includes a first cleaning blade that is in contact with the transfer belt, and a cleaning roller that is in contact with the transfer belt and electrically cleans the transfer belt. 3. And a second cleaning blade abutting on the cleaning roller. 3. The transfer conveyance device according to claim 2, wherein the first cleaning blade is fixed to contact the transfer belt using only elastic deformation of the blade, and the second cleaning blade includes: A transfer member configured to be pressed against the cleaning roller by a pressing member such as a spring. 4. The transfer conveyance device according to claim 1, wherein the positioning side plate is a side plate formed of a sheet metal member. 5. The transfer / transport apparatus according to claim 1, wherein the positioning side plate is positioned on the housing at a bearing position of the drive roller. 5. The transfer conveyance device according to claim 1, wherein the positioning side plate is positioned with respect to a member on the image forming apparatus main body side by a jig simulating the image forming apparatus. 6. Transfer transfer device. An image forming apparatus using the transfer / conveying apparatus according to claim 1.

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