JP7380138B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus that forms an image on paper.

In an image forming apparatus, a charged photoreceptor is exposed to light based on image data to form an electrostatic latent image, and a developing unit is used to attach toner to the photoreceptor, thereby converting the electrostatic latent image into a toner image. Develop as. This toner image is then transferred to a transfer belt, and the toner image transferred to the transfer belt is transferred to a recording medium such as paper (hereinafter referred to as paper). Then, the fixing roller heats and presses the paper onto which the toner image has been transferred, thereby fixing the toner image onto the paper.

Such an image forming apparatus is provided with a cleaning device that uses a blade to remove toner remaining on the surface of an image bearing member such as a photoreceptor or an intermediate transfer belt. The toner collected by the cleaning device, so-called waste toner, is conveyed to a discharge duct and discharged into the discharge duct. The waste toner discharged into the discharge duct is collected by the toner collecting section.

As a conventional toner collecting section, for example, there is one described in Patent Document 1. Patent Document 1 describes a cyclone section that centrifugally separates toner from toner-containing air, a collection section that collects the toner separated by the cyclone section, and a system that allows the air after the toner has been separated by the cyclone section to pass through. A technology including a filter section is described. Further, the technique described in Patent Document 1 includes a fan that generates a flow of toner-containing air.

JP2017-90645A

In recent years, waste toner has increased as productivity has improved, so there is a need to increase the suction power of the toner collecting section. However, since the cyclone portion is formed by overlapping a plurality of covers, when the suction force is increased, there is a risk that toner may leak out from the gaps created between the covers.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide an image forming apparatus that can prevent toner from leaking out from gaps between covers.

In order to solve the above problems and achieve the objects of the present invention, an image forming apparatus of the present invention includes an image forming section that forms an image on paper, and a toner collecting section that collects toner scattered around the image forming section. It has a section and a. The toner collecting section includes a cyclone section, a filter, a toner collecting section, a collecting section main body, and a suction fan. The cyclone section centrifugally separates the toner from the air containing the toner and causes it to fall. The filter passes the air discharged from the cyclone section. The toner collecting section collects the toner separated by the cyclone section. The collecting section main body is formed with a cyclone section, a toner collecting section, and a filter installation section in which a filter is installed. A suction fan sucks air.
The collection section main body includes a first cover and a second cover that overlaps with the first cover to form a cyclone section, a toner collection section, and a filter installation section. The first cover and the second cover have joint portions that overlap each other, and the joint portions are formed with stepped portions that fit into each other.

According to the image forming apparatus having the above configuration, it is possible to prevent toner from leaking out from the gaps between the parts.

1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. 1 is a perspective view showing a toner collecting section in an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a front view showing a first cover in an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a front view showing a second cover in the image forming apparatus according to the embodiment of the present invention. It is a perspective view showing the cylindrical part of the cyclone part in the first cover concerning the example of an embodiment of the present invention. It is a front view showing the cylindrical part of the cyclone part in the first cover concerning the example of an embodiment of the present invention. It is a perspective view showing the conical part of the cyclone part in the 1st cover concerning the example of an embodiment of the present invention. It is a perspective view showing the cylindrical part of the cyclone part in the second cover concerning the example of an embodiment of the present invention. It is a sectional view showing a cyclone part concerning an example of an embodiment of the present invention. FIG. 9 is an enlarged view of the main part of FIG. 9; FIG. 1 is a perspective view showing a dustproof tape according to an embodiment of the present invention. This figure shows the operation of the toner when it rotates around the cyclone part. FIG. 12A shows a conventional toner collecting part without a stepped part, and FIG. 12B shows a toner collecting part according to an embodiment of the present invention. FIG.

Embodiments for implementing the image forming apparatus of the present invention will be described below with reference to FIGS. 1 to 12. Note that common members in each figure are given the same reference numerals. Furthermore, the present invention is not limited to the following embodiments.

1. Embodiment 1-1. Configuration of Image Forming Apparatus First, the overall configuration of an image forming apparatus according to an embodiment of the present invention (hereinafter referred to as "this example") will be described. FIG. 1 is a schematic configuration diagram of an image forming apparatus 1 of this example.

The image forming apparatus 1 of this example forms an image on paper using an electrophotographic method, and superimposes toner of four colors: yellow (Y), magenta (M), cyan (C), and black (Bk). This is a tandem type color image forming apparatus.

As shown in FIG. 1, the image forming apparatus 1 includes a document transport section 10, a paper storage section 20, an image reading section 30, an image forming section 40, an intermediate transfer belt 50, a secondary transfer section 70, A fixing section 80 is provided. The image forming apparatus 1 also includes a discharge duct 90 and a toner collection section 100.

The document transport section 10 includes a document feed table 11 on which a document is set, and a plurality of rollers 12 . The originals G set on the original feeding table 11 of the original transporting section 10 are transported one by one to the reading position of the image reading section 30 by a plurality of rollers 12 . The image reading unit 30 reads the image of the original G transported by the original transport unit 10 or the original placed on the original platen 13, and generates an image signal.

The paper storage section 20 is arranged at the lower part of the main body of the apparatus, and a plurality of paper storage sections 20 are provided depending on the size of the paper S. This paper S is fed by the paper feed section 21 and sent to the conveyance section 23, and then conveyed by the conveyance section 23 to the secondary transfer section 70, which is a transfer position. In other words, the transport unit 23 functions to transport the paper S fed from the paper feed unit 21 to the secondary transfer unit 70, and forms a transport path for transporting the paper S. Further, a manual feed section 22 is provided near the paper storage section 20. From this manual feed section 22, paper of a size not stored in the paper storage section 20, tag paper with a tag, special paper such as an OHP sheet is sent to the transfer position.

An image forming section 40 and an intermediate transfer belt 50 are arranged between the image reading section 30 and the paper storage section 20. The image forming section 40 includes four image forming units 40Y, 40M, 40C, and 40K to form toner images of yellow (Y), magenta (M), cyan (C), and black (Bk). .

The first image forming unit 40Y forms a yellow toner image, and the second image forming unit 40M forms a magenta toner image. Further, the third image forming unit 40C forms a cyan toner image, and the fourth image forming unit 40K forms a black toner image. Since these four image forming units 40Y, 40M, 40C, and 40K each have the same configuration, the first image forming unit 40Y will be described here.

The first image forming unit 40Y includes a drum-shaped photoreceptor 41 as an image carrier, a charging section 42 arranged around the photoreceptor 41, an exposing section 43, a developing section 44, and a cleaning section 45. have. The photoreceptor 41 is rotated counterclockwise by a drive motor (not shown). The charging unit 42 charges the photoreceptor 41 to uniformly charge the surface of the photoreceptor 41. The exposure unit 43 performs exposure scanning on the surface of the photoreceptor 41 based on the image data read from the document G to form an electrostatic latent image on the photoreceptor 41 .

The developing section 44 attaches yellow toner to the electrostatic latent image formed on the photoreceptor 41, which is an image carrier. As a result, a yellow toner image is formed on the surface of the photoreceptor 41. Note that the developing section 44 of the second image forming unit 40M attaches magenta toner to the photoreceptor 41, and the developing section 44 of the third image forming unit 40C attaches cyan toner to the photoreceptor 41. Then, the developing section 44 of the fourth image forming unit 40K attaches black toner to the photoreceptor 41.

The toner adhering to the photoreceptor 41 is transferred to an intermediate transfer belt 50, which is an example of an image carrier. The cleaning unit 45 removes toner remaining on the surface of the photoreceptor 41 after being transferred to the intermediate transfer belt 50 .

A discharge duct 90 is arranged on the back side of the apparatus main body of the four image forming units 40Y, 40M, 40C, and 40K. The toner scattered by the four image forming units 40Y, 40M, 40C, and 40K is then discharged to the discharge duct 90. A toner collecting section 100 is arranged vertically below the discharge duct 90. The detailed configuration of the toner collecting section 100 will be described later.

The intermediate transfer belt 50 is formed in an endless shape and rotates clockwise in the opposite direction to the rotation direction of the photoreceptor 41 by a drive motor (not shown). A primary transfer section 51 is provided on the intermediate transfer belt 50 at a position facing the photoreceptor 41 of each image forming unit 40Y, 40M, 40C, and 40K. The primary transfer section 51 transfers the toner image formed on the photoreceptor 41 onto the intermediate transfer belt 50 by applying a polarity opposite to that of the toner to the intermediate transfer belt 50 .

As the intermediate transfer belt 50 rotates, toner images formed by the four image forming units 40Y, 40M, 40C, and 40K are sequentially transferred onto the surface of the intermediate transfer belt 50. As a result, yellow, magenta, cyan, and black toner images are superimposed on the intermediate transfer belt 50 to form a color image.

A secondary transfer section 70 including a secondary transfer roller is arranged near the intermediate transfer belt 50 and downstream of the conveyance section 23 . The secondary transfer section 70 transfers the color image formed on the intermediate transfer belt 50 onto the paper S sent by the transport section 23 .

The cleaning unit 52 removes toner remaining on the surface of the intermediate transfer belt 50 after being transferred to the paper S. Furthermore, a fixing section 80 is provided on the paper S discharge side of the secondary transfer section 70 . The fixing unit 80 fixes the toner image transferred to the paper S by heating and applying pressure.

The fixing section 80 has a pair of rollers. In the fixing unit 80, the paper S having an unfixed toner image is held between a pair of rollers and heated under pressure to fix the toner image on the summary S.

A switching gate 24 is arranged downstream of the fixing section 80. The switching gate 24 switches the conveyance path of the sheet S that has passed through the fixing section 80. That is, the switching gate 24 causes the paper S to advance straight when performing face-up paper ejection in single-sided image formation. Thereby, the paper S is ejected by the pair of paper ejection rollers 25. Further, the switching gate 24 guides the paper S downward when performing face-down paper ejection in which the image forming surface faces downward in single-sided image formation, and when performing double-sided image formation.

When performing face-down paper ejection, the paper S is guided downward by the switching gate 24, and then reversed and transported upward by the paper reversing conveyance section 26. Thereby, the paper S is ejected by the pair of paper ejection rollers 25. When double-sided image formation is performed, the paper S is guided downward by the switching gate 24, then turned upside down by the paper reversing transport section 26, and sent again to the transfer position by the paper refeed path 27.

Furthermore, a post-processing device that folds the paper S, performs stapling processing, etc. on the paper S may be arranged downstream of the pair of paper ejection rollers 25.

1-2. Example of Configuration of Toner Collection Unit Next, the configuration of the toner collection unit 100 will be described with reference to FIGS. 2 to 5.
FIG. 2 is a perspective view showing the toner collecting section 100.

As shown in FIG. 2, the toner collecting section 100 includes a hollow collecting section main body 110, a suction fan 120, and a plurality of filters 130 (see FIG. 3). The collection unit main body 110 has a first cover 140 and a second cover 150. Moreover, the collection part main body 110 is formed by overlapping the first cover 140 and the second cover 150 and fixing the first cover 140 and the second cover 150 with a plurality of fixing screws.

The collection unit main body 110 is provided with a cyclone unit 210, a filter installation unit 220, a toner recovery unit 230, and a communication path 240. A suction port 112 is formed in the side surface 111 of the collection section main body 110 on the filter installation section 220 side. A suction fan 120 is installed in this suction port 112 . That is, in the toner collecting section 100 of this example, the suction fan 120 is directly attached to the side surface 111 of the collecting section main body 110 without using a duct or the like.

3 is a front view showing the first cover 140, and FIG. 4 is a front view showing the second cover 150.
As shown in FIGS. 3 and 4, the cyclone section 210 is arranged on the opposite side of the side surface section 111 of the collection section main body 110 where the suction port 112 is formed. The cyclone section 210 has a cylindrical section 211 and a hollow conical section 212 continuous to the cylindrical section 211. The cylindrical portion 211 and the conical portion 212 are arranged so that their axial directions are parallel to the vertical direction (the direction in which gravity acts).

The cylindrical part 211 is formed at the upper part of the cyclone part 210, and the conical part 212 is formed at the lower part of the cyclone part 210. Further, the inner diameter of the conical portion 212 decreases continuously as it goes downward in the vertical direction. In other words, the inner diameter of the conical portion 212 continues to decrease as the distance from the cylindrical portion 211 increases.

Furthermore, an attachment port 213 is formed at the upper end of the cylindrical portion 211 . Further, a cyclone outlet 214 is formed at the lower part of the cyclone section 210, that is, at the lower end of the conical section 212. Further, the cylindrical portion 211 of the first cover 140 has an inlet port 141 formed therein.

The suction port 141 communicates with the exhaust duct 90. Then, air containing toner flows into the cyclone section 210 from the discharge duct 90 through the suction port 141. Then, the air containing toner swirls along the inner periphery of the cylindrical portion 211 and the conical portion 212 of the cyclone portion 210. As a result, a swirling flow in which air swirls is generated inside the cyclone section 210.

The toner in the swirling flow moves in the radial direction due to the centrifugal force exerted by the circular motion of the object. Therefore, most of the toner is separated from the air. Furthermore, a conical part 212 whose inner diameter is narrowed is formed at the lower part of the cyclone part 210. This conical portion 212 increases the swirling speed of the swirling flow and increases the centrifugal force acting on the object. As a result, toner can be efficiently separated from air.

Further, the attachment port 213 in the cyclone section 210 communicates with the communication path 240. An inner cylinder 215 is attached to the attachment port 213. The inner cylinder 215 is formed into a substantially cylindrical shape. The axial direction of this inner cylinder 215 coincides with the axial direction of the cyclone section 210.

An outer flange portion 215b is formed at the upper end of the inner cylinder 215 in the vertical direction. The outer flange portion 215b fits into the outer edge of the attachment port 213. Further, the cylindrical hole 215a of the inner cylinder 215 communicates with the communication path 240. Air from which the toner has been separated passes through the cylindrical hole 215a and the communication path 240.

A toner recovery section 230 is provided below the cyclone section 210. The toner collecting section 230 is formed into a hollow, substantially rectangular parallelepiped shape. The toner collection section 230 and the cyclone section 210 communicate with each other via the cyclone discharge port 214. The toner collecting section 230 stores the toner separated from the air by the cyclone section 210.

Further, a winding prevention section 250 is arranged at the cyclone outlet 214. The winding prevention section 250 has a main body 251 and a fixing piece 252. The main body 251 is formed into a substantially circular flat plate shape. The diameter of the main body 251 is formed to be slightly smaller than the diameter of the cyclone outlet 214. Therefore, a predetermined gap is formed between the outer edge of the main body 251 and the peripheral edge of the cyclone outlet 214. The toner separated by the cyclone section 210 is collected from this gap into a toner collection section.

A fixing piece 252 is provided on the bottom surface of the main body 251 in the vertical direction. The fixing piece 252 is fixed to the inner wall surfaces of the first cover 140 and the second cover 150. Thereby, the main body 251 is placed at the cyclone outlet 214.

Furthermore, a filter installation section 220 is formed on the side of the cyclone section 210. The filter installation part 220 is formed into a hollow, substantially rectangular parallelepiped shape. Moreover, the upper part of the filter installation part 220 communicates with the communication path 240. Thereby, the cyclone section 210 and the filter installation section 220 are connected via the communication path 240.

A filter 130 is installed in the filter installation section 220 . As the filter 130, for example, a toner dustproof filter or an ozone catalyst filter is applied. The filter 130 collects a small amount of toner contained in the air discharged from the cyclone section 210. This cleans the air that has passed through the filter 130. In order to increase the air purification effect, it is preferable to arrange a plurality of filters 130 one on top of the other in the direction in which the air passes.

Further, a suction port 112 is opened in the side surface 111 of the filter installation part 220 on the opposite side from the cyclone part 210. The suction port 112 faces the conical portion 212 of the cyclone section 210 via a first suction side joint 145 of the first cover 140 and a second suction side joint 155 of the second cover 150, which will be described later. Then, air in the filter installation section 220, the communication path 240, and the cyclone section 210 is sucked by the suction fan 120 through the suction port 112.

In this way, by directly attaching the suction fan 120 to the collection section main body 110, suction resistance received from the duct or the like can be reduced. As a result, the suction force at the toner collecting section 100 can be improved without increasing the performance of the suction fan 120.

However, by directly attaching the suction fan 120 to the collection unit main body 110, there is a risk that toner may be directly suctioned from the mating surface of the first cover 140 and the second cover 150 in the cyclone unit 210.

Further, as shown in FIG. 3, the first cover 140 is formed with a first suction side joint part 145 and a first outer joint part 146. The first suction side joint part 145 is formed between the cyclone part 210 and the filter installation part 220. The first outer joint portion 146 is formed at the end opposite to the filter installation portion 220 with the cyclone portion 210 interposed therebetween.

A plurality of fixing holes 147 are provided in the first suction side joint part 145 and the first outer joint part 146. The plurality of fixing holes 147 are formed at regular intervals along the axial direction (vertical direction) of the cyclone section 210. Further, the fixing hole 147 is also formed at a corner of the cyclone portion 210 on the upper end portion 210a side in the vertical direction (see FIG. 6).

Similarly, as shown in FIG. 4, the second cover 150 is formed with a second suction side joint part 155 and a second outer joint part 156. The second suction side joint part 155 is formed between the cyclone part 210 and the filter installation part 220. The second outer joint portion 156 is formed at the end opposite to the filter installation portion 220 with the cyclone portion 210 interposed therebetween.

Furthermore, a plurality of fixing holes 157 are provided in the second suction side joint part 155 and the second outer joint part 156. The plurality of fixing holes 157 are formed at regular intervals along the axial direction (vertical direction) of the cyclone section 210. Furthermore, the fixing hole 157 is also formed at a corner of the cyclone portion 210 on the upper end portion 210a side in the vertical direction.

The first suction side joint part 145 of the first cover 140 and the second suction side joint part 155 of the second cover 150 overlap, and the first outer joint part 146 of the first cover 140 and the second outer joint part of the second cover 150 overlap. 156 overlap. As a result, a cyclone section 210 is formed. Then, by fastening and fixing the fixing screws into the fixing holes 147 and 157, the first cover 140 and the second cover 150 are fixed together.

Moreover, by arranging the fixing holes 147 and 157 into which the fixing screws are screwed together at equal intervals, the first suction side joint part 145 and the second suction side joint part 155 can be overlapped in a well-balanced manner. This makes it possible to reduce the gap created between the first suction side joint part 145 and the second suction side joint part 155, and toner can be prevented from leaking to the outside of the cyclone part 210 from this gap.

Here, toner tends to accumulate at the corners of the upper end 210a of the cyclone section 210. Therefore, in this example, by arranging the fixing holes 147 and 157 at the corners of the upper end 210a of the cyclone section 210, the gap between the corners of the upper end 210a of the cyclone section 210 can be reduced. This makes it possible to prevent toner from leaking to the outside of the cyclone section 210 from locations where toner tends to accumulate.

Furthermore, a conical part 212 whose inner diameter is narrowed is formed at the lower part of the cyclone part 210. Therefore, the widthwise length h2 of the lower end portions of the first suction side joint portion 145 and the second suction side joint portion 155 is longer than the widthwise length h1 of the upper end portion. That is, the area where the first suction side joint part 145 and the second suction side joint part 155 overlap (ground contact area) is set to be larger in the lower conical part 212 than in the upper cylindrical part 211 in the vertical direction. Here, the larger the overlapping area between parts, the more difficult it is for dust (toner) to leak to the outside. That is, the area around the conical portion 212 in the cyclone portion 210 is configured to prevent toner from leaking.

As described above, the suction fan 120 is disposed at a position facing the conical portion 212 where toner is unlikely to leak. This can prevent toner from leaking from the mating surfaces of the first cover 140 and the second cover 150 in the cyclone section 210.

In addition, in this example, by providing the conical part 212 in the cyclone part 210, the ground contact area of the first suction side joint part 145 and the second suction side joint part 155, which are greatly affected by the suction fan 120, is increased. has been described, but is not limited to this. For example, the cyclone section 210 may not include the conical section 212 whose inner diameter narrows. Then, the ground contact area of the first cover 140 and the second cover 150 that is more affected by the suction fan 120, that is, the part that faces the suction port 112, may be made larger than other parts.

FIG. 5 is a perspective view showing the cylindrical portion 211 of the cyclone portion 210 in the first cover 140, and FIG. 6 is a front view. Further, FIG. 7 is a perspective view showing the conical part 212 of the cyclone part 210 in the first cover 140.

As shown in FIGS. 5 to 7, a first suction side stepped portion 148 is formed at a corner of the first suction side joint portion 145 on the inner wall surface side of the cyclone portion 210. As shown in FIGS. Further, a first outer stepped portion 149 is formed at a corner of the first outer joint portion 146 on the inner wall surface side of the cyclone portion 210 . The first suction side stepped portion 148 is a recessed portion recessed in a direction opposite to the direction in which the first suction side joint portion 145 overlaps the second suction side joint portion 155 . Furthermore, the first outer step portion 149 is a convex portion that protrudes from the first outer joint portion 146 in a direction in which it overlaps with the second outer joint portion 156 .

As shown in FIG. 6, the upper end 148a of the first suction side step 148 and the upper end 149a of the first outer step 149 are located below the upper end 210a of the cyclone section 210. Further, as shown in FIGS. 5 and 7, the first suction side step part 148 and the first outer step part 149 extend from the cylindrical part 211 of the cyclone part 210 to the lower end of the conical part 212, that is, the cyclone outlet 214. There is.

FIG. 8 is a perspective view showing the cylindrical part 211 of the cyclone part 210 in the second cover 150.
As shown in FIGS. 4 and 8, a second suction side stepped portion 158 is formed at a corner of the second suction side joint portion 155 on the inner wall surface side of the cyclone portion 210. As shown in FIGS. Further, a second outer step portion 159 is formed at a corner of the second outer joint portion 156 on the inner wall surface side of the cyclone portion 210 . As shown in FIG. 8 , the second suction side stepped portion 158 is a convex portion that protrudes from the second suction side joint portion 155 in a direction in which it overlaps with the first suction side joint portion 145 . Further, the second outer step portion 159 is a recessed portion recessed from the second outer joint portion 156 in a direction opposite to the first outer joint portion 146 .

Further, the second suction side step portion 158 and the second outer step portion 159 extend from the vicinity of the upper end portion 210a of the cyclone portion 210 to the conical portion 212, similarly to the first suction side step portion 148 and the first outer step portion 149. It extends to the lower end, ie, to the cyclone outlet 214.

FIG. 9 is a sectional view showing the cyclone section 210, and FIG. 10 is an enlarged view showing the main part of FIG.
As shown in FIG. 9, when the first cover 140 and the second cover 150 are overlapped, the first suction side joint part 145 and the second suction side joint part 155 overlap, and the first outer joint part 146 and the second outer joint part 155 overlap. The joints 156 overlap. Further, as shown in FIG. 10, the second suction side step portion 158 fits into the first suction side step portion 148. Further, the first outer step portion 149 fits into the second outer step portion 159.

Here, in order to smoothly fit the first suction side step part 148 and the second suction side step part 158, and the first outer step part 149 and the second outer step part 159, each step part 148, 149, 158 , 159 are provided with gaps at their upper ends. Here, if the upper end portions of each of the stepped portions 148, 149, 158, and 159 are aligned with the upper end portion 210a of the cyclone portion 210, a gap may occur in the upper end portion 210a of the cyclone portion 210, and toner may leak out. .

As described above, the upper end portions of each of the step portions 148, 149, 158, and 159 are arranged below the upper end portion 210a of the cyclone portion 210. Thereby, the gap between the mating surfaces at the upper end 210a of the cyclone section 210 can be reduced. Note that the upper end portions of the stepped portions 148, 149, 158, and 159 do not need to coincide with the upper end portion 210a of the cyclone portion 210, and may be located above the upper end portion 210a of the cyclone portion 210.

Further, as shown in FIG. 3, a dustproof tape 160 is attached to the first suction side joint portion 145. The dustproof tape 160 is interposed between the first suction side joint 145 and the second suction side joint 155 .

FIG. 11 is a perspective view showing the dustproof tape 160.
As shown in FIGS. 3 and 11, the dustproof tape 160 is formed into a substantially flat plate shape. Further, the dustproof tape 160 has a main surface portion 161, a fixing portion 162, and a wide portion 164.

The main surface portion 161 extends continuously from the upper end to the lower end of the first suction side joint portion 145 and the second suction side joint portion 155. A wide portion 164 is formed at the lower end of the main surface portion 161 . The wide portion 164 is formed to have a longer length in the width direction than other portions, corresponding to the shapes of the lower end portions of the first suction side joint portion 145 and the second suction side joint portion 155.

The fixing parts 162 are formed at equal intervals in the vertical direction of the main surface part 161. Further, the fixing part 162 is formed at a position facing the fixing hole 147 provided in the first suction side joint part 145. The fixing portion 162 has an insertion hole 163 through which a fixing screw is inserted. Therefore, the dustproof tape 160 surrounds the fixing screw.

Furthermore, by interposing the dustproof tape 160 between the first suction side joint 145 and the second suction side joint 155, toner can be cyclopedically removed from the gap between the first suction side joint 145 and the second suction side joint 155. Leakage to the outside of the portion 210 can be more effectively prevented.

The dustproof tape 160 is not limited to the example shown in FIG. 11. For example, the shape may have a uniform length in the width direction from the upper end of the main surface portion 161 to the wide portion 164, and various other shapes may be applied. Note that the dustproof tape 160 is a tape that is continuous from the upper end 210a to the lower end of the cyclone section 210 in the vertical direction.

2. Operation Example of Toner Collection Unit Next, an operation example of the toner collection unit 100 having the above-described configuration will be described.
First, as shown in FIGS. 3 and 9, air containing toner is fed into the cyclone section 210 from the suction port 141. The cyclone section 210 swirls the fed air containing toner within the cyclone section 210 to generate a swirling flow. As a result, most of the toner in the air containing toner is separated from the air (centrifuged).

The separated toner falls below the cyclone section 210 due to its own weight, passes through the gap formed between the main body 251 of the anti-rolling section 250 and the peripheral edge of the cyclone discharge port 214, and enters the toner collection section 230. to fall.

On the other hand, air flows into the communication path 240 through the cylindrical hole 215a of the inner cylinder 215 provided in the cyclone section 210. Then, the air flows into the internal space of the filter installation section 220 via the communication path 240 and passes through the filter 130 installed in the filter installation section 220. The filter 130 collects a small amount of toner contained in the air discharged from the cyclone section 210. The air that has passed through the filter 130 is sucked into the suction fan 120 through the suction port 112 and flows out of the collection unit main body 110 .

FIG. 12 shows the operation when toner rotates in the cyclone section 210. FIG. 12A shows a conventional toner collecting section without a stepped section, and FIG. 12B shows the toner collecting section 100 of this example. FIG.
As shown in FIG. 12A, the toner T1 is sucked into the gap between the first cover 140A and the second cover 150A by the suction fan while rotating inside the cyclone section 210A. Therefore, in the toner collecting section that does not have a stepped portion, the toner T1 enters the gap between the first cover 140A and the second cover 150A.

As shown in FIG. 12B, in the toner collecting section 100 of this example, the first cover 140 is provided with a first suction side step part 148 and the first outer step part 149, and the second cover 150 is provided with a first suction side step part 149. 148, and a second outer step portion 159 into which the first outer step portion 149 fits. As a result, the suction force from the suction fan 120 is inhibited by the first suction side step portion 148 and the second suction side step portion 158 . As a result, toner T1 can be prevented from entering the gap between the first cover 140 and the second cover 150.

Further, as shown in FIGS. 9, 10, and 12B, the upstream side in the turning direction of the first suction side step part 148 and the second suction side step part 158 is a convex part, and the downstream side is a concave part. Further, the second suction side step portion 158 protrudes substantially parallel to the turning direction. Therefore, in order for the toner T1 to enter between the first suction side step portion 148 and the second suction side step portion 158, it is necessary to move against the rotation direction within the cyclone portion 210. Thereby, even if the suction fan 120 is installed in the collection unit main body 110 and the suction power is increased, leakage from the gap between the first cover 140 and the second cover 150 can be prevented.

Further, as shown in FIGS. 4 and 7, the first suction side stepped portion 148 and the second suction side stepped portion 158 extend to the conical portion 212, which is greatly influenced by the suction fan 120. Thereby, it is possible to prevent the toner T1 from leaking to the outside from a location that is greatly affected by the suction fan 120.

Note that the second suction side step portion 158 and the first outer step portion 149, which are convex portions, are located on the inner side of the cyclone portion 210 in the radial direction than the first suction side step portion 148 and the second outer step portion 159 that fit together. Preferably, it protrudes toward the target. This makes it difficult for the toner T1 to enter the gap between the first suction side step part 148 and the second suction side step part 158 and the gap between the first outer step part 149 and the second outer step part 159.

The embodiments of the image forming apparatus have been described above, including their effects. However, the image forming apparatus of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the invention as set forth in the claims.

In the embodiment described above, a color image is formed using four sets of image forming units 40Y, 40M, 40C, and 40K, but the image forming apparatus according to the present invention uses one image forming unit. It is also possible to use a configuration in which a monochromatic image is formed. Further, the image forming apparatus is not limited to a copying machine, but may be a printer, a facsimile machine, or a multifunctional device having multiple functions.

Furthermore, in the above-described embodiment, an example was described in which the suction fan 120 was attached to the side surface portion 111 of the collection section main body 110, but the present invention is not limited to this. For example, the suction fan 120 and the collection section main body 110 may be connected via a suction duct, and the suction fan 120 may be arranged at a position away from the collection section main body 110.

In addition, although words such as "parallel" and "orthogonal" are used in this specification, these do not mean strictly "parallel" and "orthogonal", but include "parallel" and "orthogonal". , and may also be in a "substantially parallel" or "substantially orthogonal" state within the range where the function can be achieved.

DESCRIPTION OF SYMBOLS 1... Image forming apparatus, 10... Original conveyance part, 11... Original paper feeding table, 13... Original table, 20... Paper storage part, 21... Paper feeding part, 30... Image reading part, 40... Image forming part, 50... Intermediate transfer belt, 51... Primary transfer section, 70... Secondary transfer section, 80... Fixing section, 90... Discharge duct, 100... Toner collection section, 110... Collection section main body, 111... Side surface section, 112... Suction Port, 120... Suction fan, 130... Filter, 140... First cover, 141... Suction port, 145... First suction side joint, 146... First outer joint, 147, 157... Fixing hole, 148... First Suction side step portion, 148a, 149a...Top end portion, 149...First outer step portion, 150...Second cover, 155...Second suction side joint portion, 156...Second outer joint portion, 158...Second suction side step portion Part, 159... Second outer step part, 160... Dustproof tape, 161... Main surface part, 162... Fixing part, 163... Insertion hole, 164... Wide part, 210... Cyclone part, 210a... Upper end part, 211... Cylindrical part, 212...Conical part, 213...Mounting port, 214...Cyclone discharge port, 215...Inner cylinder, 215a...Cylinder hole, 215b...Outer flange part, 220...Filter installation part, 230...Toner collection part, 240...Communication path, 250... ...Win up prevention part, T1...Toner

Claims (9)

an image forming unit that forms an image on paper;
a toner collecting section that collects toner scattered around the image forming section;
The toner collecting section includes:
a cyclone unit that centrifugally separates the toner from the air containing the toner and drops the toner;
a filter that passes air discharged from the cyclone section;
a toner collection unit that collects the toner separated by the cyclone unit;
a collection unit main body in which the cyclone unit, the toner collection unit, and a filter installation unit for installing the filter are formed;
a suction fan that sucks the air;
The collection unit main body is
a first cover;
a second cover that overlaps with the first cover to form the cyclone section, the toner collection section, and the filter installation section;
The first cover and the second cover have joint portions that overlap each other,
A stepped portion that fits into each other is formed in the joint portion ,
A first suction side joint part is formed between the cyclone part and the filter installation part in the first cover,
A second suction side joint part that overlaps with the first suction side joint part is formed between the cyclone part and the filter installation part in the second cover,
The step portion is formed at a corner of the first suction side joint portion and the second suction side joint portion on the inner wall surface side of the cyclone portion,
A dustproof tape is interposed between the first suction side joint and the second suction side joint.
The dustproof tape has a fixing part formed with an insertion hole through which a fixing screw is inserted.
Image forming device. The image forming apparatus according to claim 1, wherein an upper end of the stepped portion in the vertical direction is arranged at a position that does not coincide with an upper end of the cyclone portion in the vertical direction. The image forming apparatus according to claim 2 , wherein the upper end portion of the stepped portion is located lower in the vertical direction than the upper end portion of the cyclone portion. The image forming apparatus according to claim 2 , wherein the upper end portion of the stepped portion is located above the upper end portion of the cyclone portion in the vertical direction. The image forming apparatus according to claim 2, wherein the step portion extends to a lower end of the cyclone portion in the vertical direction. A first suction side stepped portion including a recess is formed in the first suction side joint portion,
The image forming apparatus according to claim 1 , wherein the second suction side joint portion is formed with a second suction side step portion including a convex portion that fits into the first suction side step portion. The image forming apparatus according to claim 6 , wherein the first suction side step portion is disposed downstream of the second suction side step portion in a swirling direction in which the air swirls inside the cyclone portion. A first outer joint part is formed at an end of the first cover opposite to the filter installation part with the cyclone part in between,
A second outer joint part that overlaps with the first outer joint part is formed at an end of the second cover opposite to the filter installation part with the cyclone part in between,
The image forming apparatus according to claim 1 , wherein the stepped portion is formed at a corner of the first outer joint portion and the second outer joint portion on the inner wall surface side of the cyclone portion. The image according to claim 1 , wherein the first suction side joint part and the second suction side joint part are formed with fixing holes into which fixing screws are screwed at equal intervals along the vertical direction of the cyclone part. Forming device.

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