JP4387561B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is, for example, an image forming apparatus having a cleaning apparatus of a mobile body such as the transport member and the intermediate transfer body of an electrophotographic method or a transfer material. The image forming apparatus of an electrostatic recording method that is a printer or copier About.
[0002]
[Prior art]
Conventionally, various types of color image forming apparatuses have been proposed. One of them is provided with an image forming unit for each developer of different colors, and each image forming unit forms a visible image of each color on a photosensitive drum as an image carrier by a well-known image forming process. There is an electrophotographic color image forming apparatus in which a color image is obtained by sequentially transferring to a transfer material supplied from the outside and then fixing in a batch.
[0003]
In this case, the transfer material is placed on a moving body that moves in an endless manner, that is, on a conveyor belt, and is sequentially conveyed to each image forming unit, and the visible images formed on the respective photosensitive drums are sequentially transferred.
[0004]
Further, in order to clean dirt on the conveyor belt, for example, fog toner or paper dust, the corners of a plate-like viscoelastic body are pressed against the conveyor belt as a cleaning member to remove the dirt on the conveyor belt, Prevents dirt on the back of the transfer material.
[0005]
Furthermore, when a transfer material is jammed, such as when a transfer material is jammed, an image forming process is performed in a state where the transfer material is not placed and the toner is transferred onto the conveyance belt. The toner is being cleaned.
[0006]
[Problems to be solved by the invention]
Moreover, in the said conventional structure, the mechanism for obtaining sufficient pressing force is provided when cleaning by pressing the corner | angular part of a plate-shaped viscoelastic body to a conveyance belt as a cleaning member. Further, since the cleaning member needs to clean the conveying belt evenly over the entire width, the cleaning member is configured to press the cleaning member evenly against the conveying belt as much as possible. An example of the conventional configuration is shown in FIG.
[0007]
The cleaning device 200 is supported by a blade support member 220 such that a cleaner blade 202 as a cleaning member made of a plate-like viscoelastic body comes into contact with the conveyance belt 223. The cleaner blade 202 is supported so as to be rotatable about a rotation shaft 213 attached to the blade support member 220 by a rotation angle β. Further, the swinging member 212 that holds the blade support member 220 and the rotating shaft 213 is urged by the spring 210 by the swinging angle α with the swinging shaft 211 as the swing center, so that the cleaner blade 202 is transported by the conveyor belt 223. Is pressurized against.
[0008]
In the cleaning device 200 described above, in order to sufficiently clean the conveyor belt 223, a sufficient pressing force must be applied to the cleaner blade 202. Therefore, since a strong force acts on the tip of the rotating shaft 213 at the time of pressing, a highly rigid structure that can withstand it must be adopted, and a configuration using a highly rigid member, for example, a thick material, Equipment weight increases. Moreover, in order to implement | achieve a function part structure in a comparatively small space, the process with high difficulty had to be implemented, and there existed a problem that a process cost became high.
[0009]
Further, since the cleaner blade 202 is rotatably supported, there are problems that the cleaner blade 202 vibrates and stable cleaning becomes difficult or noise is generated depending on conditions.
[0010]
Furthermore, when the toner / paper dust cleaned by the cleaner blade 202 continues to stay in the pressurizing mechanism portion of the cleaning device 100 when used for a long period of time, the cleaner blade 202 rotates around the rotation shaft 213. There is a problem in that the function to be moved is hindered, the uniform pressing to the conveyor belt 223 cannot be realized, and the surface of the conveyor belt 223 becomes insufficiently cleaned.
[0011]
The above-described problem is that an image forming apparatus provided with an intermediate transfer unit, that is, an image formed on a photosensitive drum by a plurality of image forming units is once transferred onto an intermediate transfer member, and further transferred onto a transfer sheet at once. In the image forming apparatus of this type, the intermediate transfer member and the cleaning device also exist similarly.
[0012]
Further, it also exists in a cleaning device for a photosensitive drum or a photosensitive belt as an image carrier on which a toner image is formed.
[0013]
Accordingly, a main object of the present invention is to provide an image forming apparatus including a cleaning device that can apply a uniform pressing force to a moving body with a simple and low-cost configuration and has a high rigidity against the pressing force. It is.
[0014]
Another object of the present invention is to provide an image forming apparatus having a cleaning device provided with a cleaning member which is simple and low-cost and hardly generates vibration.
[0015]
Another object of the present invention is to provide an image forming apparatus provided with a cleaning device having a simple and low-cost configuration and in which an object to be cleaned does not stay.
[0016]
The above object is achieved by the image forming apparatus according to the present invention. In summary, the present invention comprises a movable image carrier;
A cleaning blade that has an elastic body that contacts the image carrier and a support plate that supports the elastic body, and removes toner on the image carrier;
An L-shaped support member having a bottom portion and an extending portion provided to extend upward from the bottom portion, and having a substantially L-shaped section in the longitudinal direction of the cleaning blade;
A support portion that is provided on a surface of the extension portion inside the L-shaped support member at a substantially center of the extension portion in the longitudinal direction of the cleaning blade, and supports the support plate;
In an image forming apparatus having
The gap between the extended portion and the support plate is below the contact portion between the elastic body and the image carrier so that the end of the cleaning blade can swing along the bottom side. On the side,
The bottom portion is a central portion of the bottom portion in the longitudinal direction of the cleaning blade, and is opposed to the first opening provided between the support plate and the extending portion, and the bottom portion of the bottom portion in the longitudinal direction of the cleaning blade. An image forming apparatus comprising: a second opening formed at a position farther from the extending portion than the first opening in a direction perpendicular to the longitudinal direction of the cleaning blade .
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter will be described in more detail with reference to an image forming equipment according to the present invention with reference to the drawings.
[0023]
Example 1
A first embodiment of the present invention will be described with reference to FIGS.
[0024]
First, the image forming apparatus of this embodiment will be described with reference to FIG. The image forming apparatus according to the present exemplary embodiment includes first, second, third, and fourth image forming units Pa, Pb, Pc, and Pd in the apparatus main body 10. The present invention can also be applied to an image forming apparatus including one or more arbitrary number of image forming units.
[0025]
The first to fourth image forming portions Pa to Pd are juxtaposed along the transfer material conveyance direction of the conveyance belt 20 which is a moving body for conveying the transfer material.
[0026]
The conveyor belt 20 is made of a dielectric sheet, is stretched around a drive roller 23, a driven roller 21, a separation roller 22, and an adjustment roller 24, and is driven to rotate in the direction of arrow A.
[0027]
A sheet feeding device 11 is provided on the right side of the apparatus main body 10 in the drawing, and a transfer material discharge port 12 is provided on the left side. The paper feeding device 11 places the transfer material 13 on the conveying belt 20 from the driven roller 21 side. A fixing device 14 is disposed adjacent to the transfer paper discharge port 12.
[0028]
The fixing device 14 receives the transfer material 13 fed from the separation roller 22 side, fixes the visible image transferred onto the transfer material 6 in each of the image forming portions Pa to Pd, and forms a permanent image.
[0029]
The driven roller 21 is disposed in the vicinity of the sheet feeding device 11, and the separation roller 22 is disposed in the vicinity of the fixing device 14, and the transfer material conveying surface (mounting surface) by the conveying belt 20 by both the rollers 21 and 22. Is forming. A driving roller 23 connected to a driving source (not shown) is disposed below the separation roller 22 in the drawing, and is brought into contact with the conveying belt 20 from the inside below the driven roller 21 in the drawing to pull the conveying belt 20. An adjustment roller 24 that freely adjusts the force is provided.
[0030]
The transport belt 20, the rollers 21 to 24, and a frame (not shown) that supports these are configured as a transport unit 20A that can be integrally removed from the apparatus main body.
[0031]
Each of the image forming portions Pa, Pb, Pc, and Pd has substantially the same configuration, and as is well known, the photosensitive drums 1a, 1b, 1c, and 1d, which are image carriers that are rotationally driven in the direction of the arrows in the drawing, are known. In the periphery of the photosensitive drums 1a to 1d, the chargers 2a, 2b, 2c and 2d for uniformly charging the photosensitive drums 1a to 1d and the photosensitive drums 1a to 1d are formed. On the developing units 3a, 3b, 3c, and 3d for developing the electrostatic latent image, the transfer chargers 4a, 4b, 4c, and 4d for transferring the developed developed image to the transfer material 13, and the photosensitive drums 1a to 1d. Drum cleaning devices 5a, 5b, 5c and 5d for removing the remaining toner are sequentially arranged in the rotation direction of the photosensitive drums 1a to 1d. Further, exposure devices 6a, 6b, 6c, and 6d are provided above the respective photosensitive drums 1a to 1d in the drawing.
[0032]
Yellow toner is supplied to the developing device 3a of the first image forming unit Pa, and magenta toner is supplied to the developing device 3c of the third image forming unit Pc. The cyan toner is stored in the developing unit 3d of the fourth image forming unit Pd.
[0033]
Further, the pixel signal corresponding to the yellow component image of the color image corresponds to the exposure device 6a of the first image forming unit Pa, and the magenta component image of the color image corresponds to the exposure device 6b of the second image forming unit Pb. The pixel signal corresponds to the cyan component image of the color image in the exposure device 6c of the third image forming unit Pc, and the black component image of the color image in the exposure device 6d of the fourth image forming unit Pd. Pixel signals corresponding to are respectively input. By receiving the electric digital pixel signals and modulating the light corresponding to the signals, the charging units 2a to 2d and the developing units 3a to 3d in the rotation direction of the photosensitive drums 1a to 1d are used. The surfaces of the photosensitive drums 1a to 1d are exposed in the drum bus direction.
[0034]
In the color image forming apparatus configured as described above, a cut sheet-like material is used as the transfer material 13, and the transfer material 13 moves in the paper feed guide of the paper feed device 11 and is sent out onto the transport belt 20. The driving roller 23 is also driven in the direction of arrow A in synchronization with this, and the transfer material 13 is placed on the conveying belt 20.
[0035]
Thereafter, a yellow image is formed on the photosensitive drum 1a of the first image forming unit Pa, a magenta image is formed on the photosensitive drum 1b of the second image forming unit Pb, and the photosensitive drum 1c of the third image forming unit Pc. A yellow image is formed on the photosensitive drum 1d and a black image is formed on the photosensitive drum 1d of the fourth image forming unit Pd. Since the principle of image formation in these image forming portions Pa to Pd is already known as the Carlson process, description thereof is omitted.
[0036]
The transfer material 13 is sequentially conveyed through the lower portions of the photosensitive drums 1a to 1d in the first to fourth image forming portions Pa to Pd by the movement of the conveying belt 20, and is conveyed toward the fixing device 14 to be first. ~ Transfer chargers 4a, 4b, 4c, and 4d of the fourth image forming sections Pa to Pd transfer the visible images of the respective colors formed in the respective image forming sections Pa to Pd sequentially on the transfer material 13 As a result, a color image is synthesized.
[0037]
After passing through the fourth image forming portion Pd, the transfer material 13 is separated from the conveyance belt 20 through a separation roller 22 having a small curvature that realizes separation from the conveyance belt 20 by using the elastic force of the transfer material 13. The The transfer material 13 separated from the conveying belt 20 is sent to a fixing device 14, and the developed images of the respective colors transferred in the fixing device 14 are fused and fixed, and then discharged from the transfer material discharge port 12, and one image. The formation cycle ends.
[0038]
In the present embodiment, a static elimination cleaning device 100 is attached to the drive roller 23 as a cleaning device for grounding the transfer material surface potential with respect to the conveyor belt 20 and cleaning dirt adhering to the transfer material placement surface. Has been.
[0039]
The neutralization cleaning apparatus 100 includes a fur brush 101 as a neutralization member having a neutralization function, a plate-like viscoelastic cleaner blade (hereinafter simply referred to as “cleaner blade”) 102 as a cleaning member, and a fur brush 101 and a cleaner blade 102. And a container 103 for storing the contaminated material generated by cleaning.
[0040]
Contaminants such as toner on the conveyor belt 20 are neutralized by the fur brush 101 and the electrical coupling force is reduced, so that the conveyor belt 20 is pressed by the drive roller 23 and the cleaner blade 102 at a predetermined contact angle and pressure. By being pinched by the pressure, it is mechanically removed from the conveyor belt 20 as an object to be cleaned.
[0041]
Further, as described above, by installing the static elimination cleaning device 100 with respect to the driving roller 23, the pressing force of the cleaner blade 102 has an effect of pressing the conveying belt 20 against the driving roller 23, and the driving roller 23 and the conveying belt are effective. Since the frictional force between 20 is assisted, the margin of the driving torque of the conveyor belt 20 can be indirectly increased.
[0042]
Next, features of the present invention will be described in detail with reference to FIGS.
[0043]
As shown in FIGS. 2 and 3, a cleaner blade 102 as a cleaning member is a viscoelastic body including a support plate 102a having a substantially L-shaped cross section and a plate-like viscoelastic body 102b attached to the support plate 102a. The edge of the viscoelastic body 102b, which is a plate-like member, presses the conveyance belt 20 wound around the drive roller 23, thereby removing toner and the like on the conveyance belt 20.
[0044]
In the cleaner blade 102, a support plate 102a is fastened and supported to a blade holder 112 as a support member by a screw 113 as a fastener and a corrugated washer 114 as an elastic seat member.
[0045]
Like the support plate 102a, the blade holder 112 has a substantially L-shaped cross section, and includes a bottom portion 112a, an extending portion 112b extending upward from the bottom portion 112a, and a standing portion extending upward at both longitudinal ends of the bottom portion 112a. 112c. A tension spring 110 as an elastic member is locked to one end of the standing portion 112c, specifically, one end far from the transport belt 20. The other end of the tension spring 110 is locked to the frame body 120 of the static elimination cleaning apparatus 100. The blade holder 112 is attached to the rotating shaft 111. Specifically, it is fastened by a screw 122 at a position away from the extending portion 112b of the bottom side portion 112a.
[0046]
In the above-described configuration, the function of pressing the cleaner blade 102 against the conveyor belt 20 is achieved by swinging the blade holder 112 by the tension spring 110 around the rotation shaft 111 at the swing angle α during pressurization. Realized.
[0047]
More specifically, as best shown in FIG. 3, a protrusion 115 protruding toward the cleaner blade 102 is provided at the center in the longitudinal direction of the blade holder 112. Cleaner blade 102 at the site (engaging portion) corresponding to the convex portion 115 is elastically coupled to the blade holder 112 through a corrugated washer 114 by a screw 113. A screw receiving portion 116 as a fastener receiving portion is provided on the upper portion of the convex portion 115.
[0048]
With such a configuration, the cleaner blade 102 linearly abuts against the conveyor belt 20 while having a swing angle β around the convex portion 115, that is, the screw receiving portion 116, and always has an equal force. Act.
[0049]
As described above, the cleaner blade 102 and blade holder 112 while sandwiched between the corrugated washer 114 is elastically coupled by a screw 113. Here, the screw 113 of the present embodiment includes a head portion 113a and a shaft portion, and the shaft portion has a so-called stepped screw structure having a reduced diameter portion 113b and an enlarged diameter portion 113c having different diameters. The diameter-reduced portion 113b on the distal end side is a screw fastening portion, and the diameter-expanded portion 113c is cylindrical. By engaging the cylindrical enlarged diameter portion 113c with the screw receiving portion 116 of the blade holder 112, the cleaner blade 102 is accurately held with respect to the blade holder 112. Then, sandwiched corrugated washer 114 in a predetermined gap formed between the head 113a and the cleaning blade 102 of the screw 113, the upper protrusion 115 of the blade holder central portion of the cleaner blade 102 in its elastic deformation force That is, it is elastically supported by the screw receiving portion 116.
[0050]
The cleaner blade 102 that is elastically supported can swing on the blade holder 112 with a swing angle β, and can apply a uniform pressing force to the direction of the drive roller 23.
[0051]
Further, the cleaning blade 102 and the blade holder 112 can be easily attached and detached.
[0052]
A mode in which the cleaner blade 102 is attached to the blade holder 112 will be further described with reference to FIGS. 3 and 4.
[0053]
The blade holder 112 is provided with five notches, that is, square holes S1, S2, S3, S4, and S5, which are long in the longitudinal direction in the bottom side portion 112a. Specifically, the two square holes S1 and S5 on the end side are arranged linearly, and the three square holes S2 to S4 on the center side are arranged linearly. Moreover, each square hole S1-S5 has length L1, L2, L3, L4, L5, respectively. The convex portion 115 is formed adjacent to the central square hole S3.
[0054]
The cleaner blade 102 realizes its function with the blade length Lc.
[0055]
The total length of the lengths L1 to L5 of the five square holes S1 to S5 is substantially equal to or longer than the length Lc of the cleaner blade 102. That is, the following formula (1) is satisfied.
[0056]
L1 + L2 + L3 + L4 + L5 ≧ Lc (1)
That is, there is a high probability that the toner that falls from the cleaner blade 102 falls into the portions L1 to L5 having a longer length. Accordingly, the toner or the like removed from the conveying belt 20 by the cleaner blade 102 can be dropped and discharged below the blade holder 112 without staying on the blade holder 112.
[0057]
At this time, toner or the like falls into the square holes S1 to S5 as spaces and is discharged, and in addition to the action of the cleaning blade 102 within the swing angle β, the cleaner blade 102 and the blade holder 112 are moved. The toner accumulated in the meantime can be positively discharged from the square holes S1 to S5 of the blade holder 112, and the retention of the toner or the like can be more effectively prevented.
[0058]
As described above, according to the present embodiment, the cleaning blade 102, the blade holder 112, and the tension spring 110, the swingable pressure support means that supports and pressurizes the cleaning blade 102, and the screw 113, a corrugated washer 114, a screw receiving portion 116 of the blade holder 112, and the like, and at a substantially central portion in the longitudinal direction of the blade holder 112, the cleaning blade 102 is linearly pressurized and swingably supported in a swingable manner. By having the support means, a uniform pressing force can be applied to the conveyor belt 20 with a simple and low-cost configuration, and a cleaning device having high rigidity against the pressing force can be obtained.
[0059]
In addition, since the moment of inertia around the rotating shaft that swingably supports the mechanism including the pressure support means is small, it is possible to set a configuration in which the natural frequency is high and a large amount of vibration is unlikely to occur.
[0060]
Example 2
Next, a second embodiment of the present invention will be described with reference to FIG.
[0061]
The image forming apparatus according to the present exemplary embodiment includes a so-called intermediate transfer body as a moving body that is rotationally driven by a driving roller 23 and performs endless circulation movement, and includes first to fourth image forming portions Pa to Pb, a paper feeding device. 13, the fixing device 14, and other components other than those related to the intermediate transfer member are the same as those in the first embodiment.
[0062]
A color toner image is formed on the intermediate transfer member 30 by the first to fourth image forming units Pa to Pd, and the transfer material 13 fed from the sheet feeding device 11 via the sheet feeding guide 32 is The color toner images are collectively transferred by the transfer charger 31, and the transfer material 13 is conveyed to the fixing device 14 to melt and fix the color toner image.
[0063]
Also for such an intermediate transfer member 30, the above-described configuration including the plate-like elastic body cleaner blade 102 simply configured to remove waste toner and the like remaining on the surface of the intermediate transfer member has the same configuration as in the first embodiment. Since the surface of the intermediate transfer body can be cleaned using the static elimination cleaning apparatus 100, the same effect as that shown in the first embodiment can be obtained.
[0064]
Example 3
As a third embodiment, the present invention is applied to a cleaning device for cleaning an image carrier of an image forming unit for forming an image, that is, a photosensitive belt as a moving member. That is, the same effect can be obtained by adopting the same configuration as in the first embodiment.
[0065]
Example 4
As a fourth embodiment, the present invention is applied to a cleaning device for cleaning an image carrier of an image forming unit for forming an image, that is, a photosensitive drum as a moving body. That is, the same effect can be obtained by adopting the same configuration as in the first embodiment.
[0066]
【The invention's effect】
As is clear from the above description , according to the present invention, a uniform pressing force can be applied to the moving body with a simple and low-cost configuration, and high rigidity against the pressing force can be obtained, and the weight of the apparatus is light. Can contribute to In addition, vibration is difficult to occur, and therefore generation of noise can be prevented.
[0067]
In addition, since the support member of the cleaning blade has a plurality of notches, it is possible to prevent the object to be cleaned from staying with a simple and low-cost configuration, and thus it is possible to ensure the oscillation of the pressure support means for a long time. Good cleaning can be performed.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an embodiment of an image forming apparatus according to the present invention.
FIG. 2 is a side view showing a main part of the cleaning device.
3 is an exploded perspective view showing a main part of the cleaning device in FIG. 2. FIG.
4 is an enlarged view of a main part showing a main part of the cleaning device of FIG. 3;
FIG. 5 is a configuration diagram showing another embodiment of the image forming apparatus according to the present invention.
FIG. 6 is a side view showing an example of a conventional cleaning device.
[Explanation of symbols]
20 Conveyor belt (moving body)
30 Intermediate transfer member (moving member)
100 Static elimination cleaning device (cleaning device)
102 Cleaner blade (cleaning member)
112 Blade holder 113 Screw (fastener)
114 Corrugated washer (elastic seat member)
115 Convex part 116 Screw receiving part (fastener receiving part)
S1-S5 Square hole (notch)

Claims (1)

A movable image carrier;
A cleaning blade that has an elastic body that contacts the image carrier and a support plate that supports the elastic body, and removes toner on the image carrier;
An L-shaped support member having a bottom portion and an extending portion provided to extend upward from the bottom portion, and having a substantially L-shaped section in the longitudinal direction of the cleaning blade;
A support portion that is provided on a surface of the extension portion inside the L-shaped support member at a substantially center of the extension portion in the longitudinal direction of the cleaning blade, and supports the support plate;
In an image forming apparatus having
The gap between the extended portion and the support plate is below the contact portion between the elastic body and the image carrier so that the end of the cleaning blade can swing along the bottom side. On the side,
The bottom portion is a central portion of the bottom portion in the longitudinal direction of the cleaning blade, and is opposed to the first opening provided between the support plate and the extending portion, and the bottom portion of the bottom portion in the longitudinal direction of the cleaning blade. An image forming apparatus comprising: a second opening formed at a position away from the extending portion from the first opening in a direction perpendicular to the longitudinal direction of the cleaning blade .

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