Toner recovery device and image forming apparatus having the same

Abstract

The present invention provides a toner recovery device and an image forming apparatus including the toner recovery device. The toner recovery device includes a toner recovery container, a toner conveyance passage, a side wall portion, a detection recess, and a detection sensor. The toner conveyance passage includes a first inclined portion inclined downward and a second inclined portion inclined downward. The first inclined portion is provided directly below the toner recovery port and extends leftward in the left-right direction orthogonal to the up-down direction. The second inclined portion is connected to the lower end portion of the first inclined portion and extends forward in the front-rear direction orthogonal to the up-down direction and the left-right direction, and the left-side end portion on the left side abuts against the inner wall surface on the left side of the toner recovery container. The detection recess has an opening between the upper end portion of the side wall portion and the inner wall surface of the toner recovery container.

Description

Technical Field

[0001] The present invention relates to a toner recovery device and an image forming apparatus including the toner recovery device. Background Art

[0002] The present invention relates to a toner recovery device and an image forming apparatus including the toner recovery device.

[0003] In an image forming apparatus (such as a copying machine, a printer, a FAX, etc.) using an electrophotographic method, a general process is as follows: an electrostatic latent image formed on an image carrier such as a photosensitive drum is visualized by toner (powder-like developer) in a developing device, and the toner image is directly transferred or transferred via an intermediate transfer member to a recording medium, and then fixed. A cleaning device is mounted in such an image forming apparatus, and the cleaning device is used to remove residual toner on the surface of the image carrier / intermediate transfer member. The residual toner removed by the cleaning device is transported and stored in a toner recovery container as waste toner. The toner recovery container is replaceable, and an installer (user / maintenance operator, etc.) can replace it appropriately.

[0004] A waste toner transport unit for transporting waste toner is provided in the cleaning device. The waste toner transport unit is provided with a toner transport passage and a screw conveyor for transporting toner. An opening is formed at the downstream end of the toner transport passage. The opening and a toner recovery port formed at the upper part of the toner recovery container are arranged side by side in the vertical direction. The waste toner in the toner transport passage is transported by the screw conveyor to the opening, and is put into the toner recovery container through the toner recovery port from the opening. The process of removing the residual toner on the image carrier continues during image formation in the image forming apparatus. In the process of removing the residual toner, the waste toner is sequentially put into the toner recovery container.

[0005] In addition, there is a toner recovery device including a detection sensor capable of detecting the amount of waste toner in the toner recovery container.

[0006] Such a detection sensor is arranged around the toner recovery port in order to detect a state where the waste toner in the toner recovery container is sufficiently stored. The detection sensor is an optical sensor such as a light interrupter, and includes a light emitting part for emitting light and a light receiving part for receiving the light emitted from the light emitting part. The light emitting part and the light receiving part are arranged to sandwich the toner recovery container from both sides in the width direction (a direction orthogonal to the vertical direction) of the toner recovery container at a specified position in the vertical direction of the toner recovery container. The detection sensor is connected to a control part provided at an arbitrary position in the image forming apparatus, detects whether there is waste toner between the light emitting part and the light receiving part (the above-mentioned specified position) based on the light receiving state of the light receiving part, and sends the detection result to the control part.

[0007] The waste toner gradually accumulates in the toner recovery container. When it reaches the above-mentioned specified position, the light emitted by the light-emitting part is blocked by the waste toner, and the light-receiving state of the light-receiving part changes. If this detection result is sent to the control part, the control part displays the replacement time of the toner recovery container on the operation screen of the image forming apparatus or the like. SUMMARY OF THE INVENTION

[0008] An object of the present invention is to provide a toner recovery device that can suppress false detection of a detection sensor and appropriately replace a toner recovery container, and an image forming apparatus including the toner recovery device.

[0009] The toner recovery device of the present invention includes: a toner recovery container formed with a toner recovery port into which waste toner on a toner carrier is input, and capable of storing the waste toner input from the toner recovery port therein; a toner conveying passage including a first inclined portion inclined downward and a second inclined portion inclined downward, the first inclined portion being provided directly below the toner recovery port and extending to the left in the left-right direction orthogonal to the up-down direction, the second inclined portion being connected to the lower end portion of the first inclined portion and extending forward in the front-rear direction orthogonal to the up-down direction and the left-right direction, and the left side end portion thereof abutting against the inner wall surface on the left side of the toner recovery container, the toner conveying passage conveying the waste toner input from the toner recovery port along the first inclined portion and the second inclined portion toward the bottom of the toner recovery container; a side wall portion standing up from the side end portion on the right side of the second inclined portion; a detection recess having an opening between the upper end portion of the side wall portion and the inner wall surface of the toner recovery container and communicating with the rear side of the second inclined portion; and a detection sensor for detecting whether there is waste toner at a specified position in the up-down direction inside the detection recess.

[0010] In addition, the image forming apparatus of the present invention includes: an image forming unit having a toner carrier and forming an image on a recording medium; a waste toner conveying unit for conveying waste toner on the toner carrier to the toner recovery port; and the toner recovery device having the above-described configuration for recovering the waste toner conveyed by the waste toner conveying unit.

[0011] According to the toner recovery device of the present invention, the first inclined portion is disposed directly below the toner recovery port, and the second inclined portion is connected to the lower end portion of the first inclined portion. Therefore, the waste toner input from the toner recovery port is conveyed to the bottom of the toner recovery container in a manner of sliding on the first inclined portion and the second inclined portion. Thus, it is possible to suppress the situation where the waste toner accumulates concentratedly directly below the toner recovery port, and thereby it is possible to effectively store the waste toner in the storage space within the toner recovery container.

[0012] In addition, a side wall portion is provided at the right side end portion of the second inclined portion, and an opening portion of the detection recess is formed between the upper end portion of the side wall portion and the inner wall surface of the toner recovery container. Therefore, the entry of the waste toner input from the toner recovery port into the detection recess is blocked by the side wall portion. Thus, the waste toner is not easily attached to the inner wall surface around the detection sensor within the detection recess, and thereby it is possible to suppress false detection of the detection sensor.

[0013] In addition, according to the configuration of the present invention, if the waste toner stored in the toner recovery container exceeds a specified amount, the waste toner accumulates to the lower end portion of the second inclined portion, and the newly input waste toner accumulates on the second inclined portion. Since the waste toner accumulated on the second inclined portion reaches the upper end portion of the side wall portion and is about to pass through the opening portion in a manner of crossing over the upper end portion of the side wall portion, the waste toner is about to enter the detection recess. Therefore, until the waste toner stored in the toner recovery container exceeds a specified amount (the amount at which the waste toner on the second inclined portion reaches the upper end of the side wall portion), the waste toner does not enter the detection recess. That is, it is possible to suppress the situation where the detection sensor falsely detects that the toner recovery container is in a full state when there is a large amount of remaining storage space for waste toner in the toner recovery container.

[0014] Therefore, it is possible to provide a toner recovery device that can suppress false detection of the detection sensor and can appropriately replace the toner recovery container.

[0015] In addition, according to the image forming apparatus of the present invention, an image forming apparatus that can replace the toner recovery container at an appropriate timing can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic cross-sectional view of an image forming apparatus 100 equipped with the toner recovery device 21 of the present invention.

[0017] Figure 2 It is a perspective view showing the toner recovery device 21 of the present invention and the waste toner conveyance unit 25.

[0018] Figure 3 It is a front sectional view showing the internal structure of the toner recovery device 21 of the present invention (using Figure 1(Cross-sectional view taken along line A-A′).

[0019] Figure 4 is taken along line B-B′ Figure 3 and is a cross-sectional view of the toner recovery device 21 of the present invention shown in the figure.

[0020] Figure 5 is taken along line C-C′ Figure 3 and is a cross-sectional view of the toner recovery device 21 of the present invention shown in the figure.

[0021] Figure 6 is taken along Figure 5 line D-D′ shown in the figure and is a cross-sectional view of the toner recovery container 23.

[0022] Figure 7 is a cross-sectional view of the toner recovery container 23 showing a state in which waste toner is stored.

[0023] Figure 8 is taken along line E-E′ Figure 7 and is a cross-sectional view of the toner recovery container 23 shown in the figure.

[0024] Figure 9 is a cross-sectional view showing a state in which waste toner is stored in the detection recess 29. Detailed Embodiments

[0025] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 is a schematic cross-sectional view of an image forming apparatus 100 loaded with the toner recovery device 21 of the present invention. Inside the main body of the image forming apparatus 100 (here, a color printer), four image forming units Pa, Pb, Pc, and Pd are sequentially provided from the upstream side in the conveyance direction ( Figure 1 the right side in the figure). The image forming units Pa to Pd correspond to images of four different colors (magenta, cyan, yellow, and black), and images of each color are sequentially formed through the processes of charging, exposure, development, and transfer.

[0026] Photosensitive drums (toner image carriers) 1a to 1d that carry visible images (toner images) of each color are rotatably provided in the image forming units Pa to Pd. In addition, an intermediate transfer belt 8 is provided adjacent to the image forming units Pa to Pd. In addition, a secondary transfer roller 9 is provided adjacent to the intermediate transfer belt 8.

[0027] The intermediate transfer belt 8 is made of a thin sheet of dielectric resin and is formed into a ring by overlapping both ends thereof, or is a seamless belt. The intermediate transfer belt 8 is hung on a driven roller 10, a driving roller 11, and a tension roller 20, and rotates together with the rotation of the driving roller 11.

[0028] The secondary transfer roller 9 is opposed to the driving roller 11 with the intermediate transfer belt 8 therebetween. A nip portion (secondary transfer nip portion) is formed between the intermediate transfer belt 8 and the secondary transfer roller 9. Further, a blade-shaped belt cleaner 19 is disposed at a position on the downstream side of the secondary transfer roller 9 with respect to the rotation direction of the intermediate transfer belt 8, and the belt cleaner 19 is for removing toner remaining on the surface of the intermediate transfer belt 8.

[0029] A paper cassette 16 is provided at the lower part of the image forming apparatus 100. Sheets S are stored in the paper cassette 16. The sheets S in the paper cassette 16 are conveyed to the secondary transfer nip portion via a paper feed roller 12a and registration rollers 12b.

[0030] Next, the image forming units Pa to Pd will be described. A charger 2a to 2d, an exposure unit 4, a developing unit 3a to 3d, and a cleaning unit 5a to 5d are provided around and below the photosensitive drums 1a to 1d.

[0031] The chargers 2a to 2d charge the photosensitive drums 1a to 1d. The exposure unit 4 exposes each photosensitive drum 1a to 1d with image information. The developing units 3a to 3d form a toner image on the photosensitive drums 1a to 1d. The developing units 3a to 3d include developing rollers (developer carriers) opposed to the photosensitive drums 1a to 1d. Toner cartridges (not shown) are respectively provided in the developing units 3a to 3d, and the toner cartridges are filled with toner of respective colors of magenta, cyan, yellow, and black in a predetermined amount. The cleaning units 5a to 5d remove the developer (toner) remaining on the photosensitive drums 1a to 1d.

[0032] If the user instructs to start forming an image, first, the chargers 2a to 2d uniformly charge the surfaces of the photosensitive drums 1a to 1d. Next, light irradiation is performed by the exposure unit 4, and an electrostatic latent image corresponding to the image signal is formed on the photosensitive drums 1a to 1d. Next, toner in the toner cartridges is supplied from the developing rollers of the developing units 3a to 3d to the photosensitive drums 1a to 1d, and the toner electrostatically adheres to the photosensitive drums 1a to 1d. Thus, a toner image corresponding to the electrostatic latent image is formed.

[0033] Then, after an electric field is applied to the intermediate transfer belt 8 at a predetermined transfer voltage, the toner images on the photosensitive drums 1a to 1d are primarily transferred onto the intermediate transfer belt 8 by the primary transfer rollers 6a to 6d. The four-color toner images after the primary transfer are formed in a predetermined positional relationship for forming a predetermined full-color image. Then, the toner remaining on the surfaces of the photosensitive drums 1a to 1d is removed by the cleaning units 5a to 5d to prepare for continuously forming a new electrostatic latent image.

[0034] If the intermediate transfer belt 8 starts to rotate clockwise, the sheet S is conveyed from the alignment roller 12b toward the secondary transfer nip portion at a prescribed timing. Then, the full-color image is secondarily transferred from the intermediate transfer belt 8 to the surface of the sheet S by the secondary transfer roller 9. The sheet S on which the toner image has been transferred is conveyed toward the fixing unit 7.

[0035] When the sheet S conveyed to the fixing unit 7 passes through the nip portion (fixing nip portion) of the fixing roller pair 13, it is heated and pressed. Then, the toner image after the secondary transfer is fixed on the surface of the sheet S, and a prescribed full-color image is formed. The sheet S on which the full-color image is formed is distributed in the conveying direction by the branch portion 14 that branches in multiple directions. When an image is formed only on one side of the sheet S, the sheet S is directly discharged to the discharge tray 17 by the discharge roller 15.

[0036] On the other hand, when an image is to be formed on both sides of the sheet S, a part of the sheet S that has passed through the fixing unit 7 is temporarily projected from the discharge roller 15 to the outside of the apparatus. In this state, by rotating the discharge roller 15 in the reverse direction, the sheet S is distributed to the sheet conveyance path 18 in a state where the image surface (the surface on which the image is formed) is turned over by the branch portion 14, and is conveyed again toward the secondary transfer nip portion. Then, the next image formed on the intermediate transfer belt 8 is transferred by the secondary transfer roller 9 to the surface of the sheet S on which the image has not yet been formed, is conveyed to the fixing unit 7, and after the toner image is fixed, is discharged to the discharge tray 17.

[0037] A toner recovery device 21 is disposed at the lower part of the apparatus. The toner recovery device 21 recovers and stores the waste toner scraped by the cleaning units 5a to 5d and the belt cleaner 19. The toner recovery device 21 is connected to the cleaning units 5a to 5d and the belt cleaner 19 via a waste toner conveyance unit 25 (waste toner conveyance portion).

[0038] The waste toner conveyance unit 25 includes a spiral conveyor 24 inside, and a discharge port 32 is formed (see Figure 2 ). The spiral conveyor 24 conveys the waste toner. The discharge port 32 is located at the downstream end portion of the waste toner conveyance unit 25 with respect to the conveyance direction of the waste toner. The waste toner conveyance unit 25 conveys the waste toner generated in the cleaning units 5a to 5d and the belt cleaner 19 toward the toner recovery device 21 through the discharge port 32.

[0039] Figure 2 is a perspective view showing the toner recovery device 21 and the waste toner conveyance unit 25 of the present invention. Figure 3 is a main cross-sectional view showing the internal structure of the toner recovery device 21 of the present invention (a cross-sectional view taken along the line A - A' of Figure 1 ). Figure 4 is taken along the line B - B' Figure 3Cross-sectional view of the toner recovery device 21 of the present invention as shown. Figure 5 It is cut along the line C-C'. Figure 3 Cross-sectional view of the toner recovery device 21 of the present invention as shown.

[0040] In addition, hereinafter, among the directions orthogonal to the vertical direction ( Figure 1 , Figure 2 , Figure 3 , Figure 5 the direction of the arrow Z-Z' as shown), the direction along the width direction of the image forming apparatus 100 is defined as the left-right direction ( Figure 1 , Figure 2 , Figure 4 , Figure 5 the direction of the arrow X-X' as shown). In addition, the direction orthogonal to the vertical direction and the left-right direction is defined as the front-rear direction ( Figure 2 , Figure 3 , Figure 4 the direction of the arrow Y-Y' as shown). Further, one of the front-rear directions (the arrow Y direction shown in each figure) is referred to as "front", and the other (the arrow Y' direction shown in each figure) is referred to as "rear". In addition, one of the left-right directions (the arrow X direction shown in each figure) is referred to as "left", and the other (the arrow X' direction shown in each figure) is referred to as "right".

[0041] As Figure 1 , Figure 2 , Figure 3 shown, the toner recovery device 21 includes a toner recovery container 23, a toner transport passage 27, a side wall portion 28, a detection recess 29, and a detection sensor 30. The toner recovery container 23 is a bottomed container capable of storing therein the waste toner transported by the waste toner transport unit 25. A toner recovery port 31 is formed on the upper surface of the toner recovery container 23. The toner recovery port 31 is a through hole that penetrates a part of the upper surface of the toner recovery container 23 in the vertical direction. The toner recovery port 31 is disposed below the discharge port 32 of the waste toner transport unit 25. The toner recovery port 31 receives the waste toner discharged from the discharge port 32 and drops the waste toner into the toner recovery container 23.

[0042] The toner transport passage 27 is disposed below the toner recovery port 31 and transports the waste toner dropped from the toner recovery port 31 into the toner recovery container 23. The toner transport passage 27 includes a first inclined portion 33 provided directly below the toner recovery port 31 and a second inclined portion 34 connected to the first inclined portion 33.

[0043] As Figure 4 , Figure 5 shown, the first inclined portion 33 is inclined toward the left in the left-right direction (Figure 4 , Figure 5 A plate-like body that slopes downward in the X direction of the arrow Figure 4 . The waste toner introduced from the toner recovery port 31 lands on the first inclined portion 33 and slides down to the lower end portion of the first inclined portion 33. The inclination angle of the first inclined portion 33 (the slope of the first inclined portion 33 with respect to the horizontal plane) is larger than the angle of repose of the waste toner.

[0044] As Figure 3 , Figure 4 shown, the second inclined portion 34 is a plate-like body that slopes downward in the forward direction of the front-rear direction ( Figure 3 , Figure 4 the Y direction of the arrow). The upper end portion of the second inclined portion 34 is connected to the inner wall surface on the rear side of the toner recovery container 23 and extends forward from the upper end portion to the lower end portion. The inclination angle of the second inclined portion 34 (the slope of the second inclined portion 34 with respect to the horizontal plane) is larger than the angle of repose of the waste toner. The upper end portion of the second inclined portion 34 is connected to the lower end portion of the first inclined portion 33. The waste toner that slides leftward on the first inclined portion 33 slides forward on the second inclined portion 34 and falls from the lower end portion of the second inclined portion 34 toward the bottom 35 of the toner recovery container 23.

[0045] Figure 6 is a cross-sectional view of the toner recovery container 23 cut along the D-D' line shown in Figure 5 . As Figure 5 , Figure 6 shown, the side wall portion 28 is formed to stand up from the side end portion on the right side of the second inclined portion 34. The side wall portion 28 extends along the conveying direction of the waste toner from the upper end portion to the lower end portion of the second inclined portion 34 (see Figure 5 ).

[0046] The side wall portion 28 includes a third inclined portion 36 that is connected to the side end portion on the right side of the second inclined portion 34. The third inclined portion 36 slopes downward and to the left from the upper end (the vertex of the side wall portion 28).

[0047] The waste toner that slides on the second inclined portion 34 passes through the area surrounded by the second inclined portion 34, the inner wall surface on the left side of the toner recovery container 23, and the third inclined portion 36. The cross-sectional area of the area surrounded by the side wall portion 28, the second inclined portion 34, and the toner recovery container 23 is substantially equal to the area of the toner conveying space in the cross-section orthogonal to the axis of the screw conveyor 24 (the space divided by the screw blade and the rotating shaft of the screw conveyor 24 and used to convey the waste toner by the rotation of the screw blade).

[0048] As Figure 6As shown, the detection recess 29 has an opening 38 between the vertex of the side wall portion 28 and the inner wall surface on the right side (in the direction of arrow X') of the toner recovery container 23, and is recessed rearward (in the direction of arrow Y') from the opening 38. The detection recess 29 communicates with the internal space of the toner recovery container 23 via the opening 38. The waste toner inside the toner recovery container 23 enters the detection recess 29 from the opening 38 and accumulates therein.

[0049] As Figure 6 shown, the detection sensor 30 is an optical sensor such as an optical interrupter, and includes a light emitting portion 39 that emits light and a light receiving portion 40 that receives the light emitted from the light emitting portion 39. The detection sensor 30 is disposed outside the toner recovery container 23 and is disposed so as to overlap the detection recess 29 in the front-rear direction. The light emitting portion 39 and the light receiving portion 40 are disposed so as to sandwich the detection recess 29 in the left-right direction. The detection sensor 30 is connected to a control portion (not shown) provided at a predetermined position within the image forming apparatus 100. The detection result of the detection sensor 30 is sent to the control portion.

[0050] The detection sensor 30 detects whether there is waste toner between the light emitting portion 39 and the light receiving portion 40 based on the light receiving state of the light receiving portion 40. Specifically, the light receiving state of the light receiving portion 40 in a state where there is no waste toner between the light emitting portion 39 and the light receiving portion 40 ( Figure 6 the state shown) is taken as the reference state. If waste toner accumulates between the light emitting portion 39 and the light receiving portion 40 (see Figure 9 ), the light emitted from the light emitting portion 39 is blocked by the waste toner, causing the light receiving state to change from the above-mentioned reference state. This detection result is sent to the control portion, and the control portion displays on the operation screen of the image forming apparatus 100, etc., the case where a predetermined amount of waste toner has been stored in the toner recovery container 23.

[0051] As described above, the waste toner introduced from the toner recovery port 31 is conveyed by the toner conveying passage 27 toward the bottom 35 of the toner recovery container 23 in such a manner that it slides on the first inclined portion 33 and the second inclined portion 34. Here, a side wall portion 28 is provided at the right-side end portion of the second inclined portion 34. Therefore, the entry of the waste toner introduced from the toner recovery port 31 into the detection recess 29 is blocked by the side wall portion 28, and it is conveyed toward the bottom 35 of the toner recovery container 23 while passing through the second inclined portion 34.

[0052] Figure 7 is a cross-sectional view of the toner recovery container 23 showing a state in which waste toner is stored. Figure 8 is a cross-sectional view of the toner recovery container 23 taken along the line E-E' Figure 7 shown. Figure 9It is a cross-sectional view showing a state in which waste toner is stored in the detection recess 29.

[0053] As Figure 7 shown, if the storage amount of waste toner in the toner recovery container 23 increases and the waste toner accumulates above the lower end of the second inclined portion 34, the waste toner continues to accumulate in the toner conveyance passage 27. As described above, the entry of the waste toner in the toner conveyance passage 27 into the detection recess 29 is blocked by the side wall portion 28. However, as Figure 9 shown, if the storage amount of waste toner in the toner recovery container 23 reaches a specified level or more and the amount of waste toner in the toner conveyance passage 27 exceeds a certain amount, the waste toner will cross over the side wall portion 28 and enter the detection recess 29 from the opening portion 38 and be stored in the detection recess 29.

[0054] The storage of the waste toner in the detection recess 29 gradually accumulates from the bottom to the top as the storage amount of the waste toner in the toner recovery container 23 increases. When the waste toner accumulates to a specified position in the detection recess 29 in the vertical direction, the light emitted from the light emitting portion 39 is blocked, and the light receiving state of the light receiving portion 40 changes. Thereby, the control unit displays on the operation screen of the image forming apparatus or the like the situation where a specified amount of waste toner has been stored in the toner recovery container 23.

[0055] As described above, the entry of the waste toner introduced from the toner recovery port 31 into the detection recess 29 is blocked by the side wall portion 28 and gradually accumulates in the toner recovery container 23. Therefore, it is possible to suppress the waste toner from adhering to the periphery of the detection sensor 30 in the detection recess 29 and causing a false detection by the detection sensor 30. In addition, since the entry of the waste toner toward the opening portion 38 is blocked by the side wall portion 28 until the storage amount of the waste toner in the toner recovery container 23 reaches a specified level or more (at least the storage amount at the lower end of the second inclined portion 34), it is possible to suppress the detection sensor 30 from detecting the waste toner in a state where the waste toner has not been sufficiently stored in the toner recovery container 23. Therefore, the replacement of the toner recovery container 23 can be effectively performed.

[0056] In addition, as described above, the third inclined portion 36 is formed on the side wall portion 28. Therefore, even if the waste toner that enters from the first inclined portion 33 toward the second inclined portion 34 collides with the side wall portion 28, it is likely to fall along the third inclined portion 36 toward the second inclined portion 34, so that the waste toner can be prevented from being fixedly attached to the side wall portion 28. In addition, since the waste toner slides down from the third inclined portion 36, the waste toner in the toner conveyance passage 27 is likely to concentrate on the second inclined portion 34. Then, when a predetermined amount of waste toner has been stored in the toner recovery container 23, the waste toner gradually accumulates from the second inclined portion 34 at the bottom in the toner conveyance passage 27. Therefore, the so-called dead space where the waste toner has not yet accumulated can be reduced, and the waste toner can be effectively stored in the toner recovery container 23.

[0057] In addition, as described above, the inclination angles of the first inclined portion 33 and the second inclined portion 34 are set to be larger than the angle of repose of the waste toner. Therefore, the waste toner that falls onto the first inclined portion 33 and the second inclined portion 34 is not retained at the falling position but is conveyed toward the downstream side of the toner conveyance passage 27. Therefore, it is possible to prevent the situation where the toner conveyance passage 27 is blocked due to the waste toner adhering to the first inclined portion 33 or the second inclined portion 34 and the waste toner cannot be stored in the toner recovery container 23.

[0058] In addition, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, the present invention is not limited to Figure 1 the tandem type color image forming apparatus shown, and of course can be applied to various image forming apparatuses having a waste toner recovery mechanism such as a rotary color copying machine, a printer, a black-and-white copying machine, a black-and-white printer, a digital multifunction machine, and a facsimile machine.

[0059] By loading the toner recovery device of the present invention, the image forming apparatus can replace the toner recovery container at an appropriate timing, thereby reducing the replacement frequency of the toner recovery container and suppressing the backflow of the waste toner.

Claims

1. A toner recycling device, characterized in that Comprising: A toner recovery container, formed with a toner recovery port for introducing waste toner on a toner carrier, and capable of accommodating the introduced waste toner therein; A toner conveyance passage, including a first inclined portion inclined downward and a second inclined portion inclined downward. The first inclined portion is provided directly below the toner recovery port and extends leftward in the left - right direction orthogonal to the up - down direction. The second inclined portion is connected to the lower end portion of the first inclined portion and extends forward in the front - rear direction orthogonal to the up - down direction and the left - right direction, and the left - hand side end portion of the second inclined portion abuts against the left - hand inner wall surface of the toner recovery container. The toner conveyance passage conveys the waste toner introduced from the toner recovery port along the first inclined portion and the second inclined portion toward the bottom of the toner recovery container; A side wall portion, connected to the right - hand side end portion of the second inclined portion and rising upward in the up - down direction from the right - hand side end portion of the second inclined portion; A detection recess, having an opening between the upper end portion of the side wall portion and the right - hand inner wall surface of the toner recovery container, and extending rearward in the front - rear direction from the opening and communicating with the rear side of the second inclined portion; And A detection sensor, detecting whether there is waste toner at a specified position in the up - down direction inside the detection recess, The detection sensor is an optical sensor, which has a light - emitting portion disposed on one side and a light - receiving portion disposed on the other side with the detection recess therebetween in the left - right direction, and detects whether there is waste toner between the light - emitting portion and the light - receiving portion based on the light - receiving state of the light - receiving portion.

2. The toner recovery device according to claim 1, wherein: The side wall portion has a third inclined portion, which inclines downward to the left from the upper end of the side wall portion.

3. The toner recovery device according to claim 1 or 2, wherein: The inclination angles of the first inclined portion and the second inclined portion are larger than the angle of repose of the waste toner.

4. An image forming apparatus, characterized in that Comprising: An image forming portion, having a toner carrier and forming an image on a recording medium; A waste toner conveyance portion, conveying the waste toner on the toner carrier to the toner recovery port; And The toner recovery device according to any one of claims 1 to 3, recovering the waste toner conveyed by the waste toner conveyance portion.

Images