Waste toner recovery device and image forming apparatus

Abstract

The present invention provides a waste toner recovery device and an image forming apparatus. The waste toner recovery device comprises: a recovery container having an inlet for storing waste powder, the inlet receiving waste powder including either used toner or developer discharged from an image forming unit; and a conveying unit swingably cantilevered within the recovery container, comprising a first conveying portion for conveying the waste powder brought in from the inlet within the recovery container with a first conveying force, and a second conveying portion for conveying the waste powder brought in from the inlet with a second conveying force less than the first conveying force.

Description

Technical Field

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

[0002] A waste colorant collection box is known, which is installed in an image forming device and collects and stores waste colorant discharged from the image forming device, including either used colorant or developer, wherein the waste colorant collection box is composed of the following parts: a box body, which is formed with a plurality of waste colorant collection ports and stores the waste colorant dropped from each collection port in an internal space; and a pair of conveying components, which are arranged along the upper limit of the waste colorant storage in the box body and parallel to each other along the collection ports and are driven to rotate, and convey the waste colorant dropped from each collection port into the box body by rotation, and the pair of conveying components make the conveying directions of the waste colorant in the box body different from each other (Japanese Patent Laid-Open No. 2008-112193). Summary of the Invention

[0003] The present invention provides a waste toner recovery device and an image forming apparatus, which can efficiently accumulate waste toner in a recovery container by accumulating waste powder in the waste toner recovery device on the upper surface of the recovery container.

[0004] According to a first aspect of the present invention, there is provided a waste toner recovery device, wherein the waste toner recovery device comprises:

[0005] a recovery container having a delivery port for receiving the waste powder, the delivery port receiving the waste powder including either used toner or developer discharged from the image forming unit; and

[0006] The conveying unit is supported by a swingable cantilever inside the recovery container, and includes a first conveying portion for conveying the waste powder brought in from the carrying-in port within the recovery container with a first conveying force, and a second conveying portion for conveying the waste powder brought in from the carrying-in port with a second conveying force smaller than the first conveying force.

[0007] According to a second aspect of the present invention, there is provided a waste toner recovery device comprising:

[0008] a recovery container having a delivery port for receiving the waste powder, the delivery port receiving the waste powder including either used toner or developer discharged from the image forming unit; and

[0009] The conveying unit is cantilever-supported in a swingable manner inside the recovery container, and includes a first conveying portion that conveys the received waste powder with a first conveying force inside the recovery container and stacks it at a first stacking profile, and a second conveying portion that conveys the waste powder with a second conveying force that is smaller than the first conveying force and stacks it at a second stacking profile that is higher than the first stacking profile.

[0010] According to the third aspect of the present invention, the conveying unit includes a spiral blade and is rotationally driven to convey the waste powder.

[0011] According to a fourth aspect of the present invention, the pitch of the spiral blades of the first conveying portion is wider than the pitch of the spiral blades of the second conveying portion.

[0012] According to the fifth aspect of the present invention, the pitch of the spiral blades of the first conveying portion is at least twice as wide as the pitch of the spiral blades of the second conveying portion.

[0013] According to a sixth aspect of the present invention, the first transport portion is formed within a range from the cantilevered base end of the transport unit to a position below the carry-in port.

[0014] According to a seventh aspect of the present invention, the transport unit includes a shaft, and the spiral blade is integrally formed with the shaft with a gap therebetween.

[0015] According to an eighth aspect of the present invention, the transport unit is formed of synthetic resin.

[0016] According to a ninth aspect of the present invention, the waste toner collecting device further includes a detecting unit configured to detect whether the waste powder accumulated in the second accumulation profile in the collection container has reached a predetermined height.

[0017] According to the 10th embodiment of the present invention, in the waste colorant recovery device, the detection unit is arranged at a height at which the waste powder reaches when the recovery container is approximately filled with the waste powder, and the height is the height at which the waste powder reaches when the waste powder stacked in the first stacking profile approximately reaches the carrying-in port.

[0018] According to the 11th embodiment of the present invention, an image forming apparatus is provided, wherein the image forming apparatus comprises: a first conveying unit that conveys waste powder recovered from an image forming unit that forms a colorant image; and a second conveying unit that conveys the waste powder so that the waste powder falls toward the waste colorant recovery device.

[0019] (Effect)

[0020] According to the first and eleventh aspects, the waste powder in the waste toner collecting device can be accumulated on the upper surface of the collecting container.

[0021] According to the second aspect, the waste powder in the waste toner collecting device can be accumulated on the upper surface of the collecting container except for the waste powder delivery port.

[0022] According to the third aspect, waste powder can be efficiently conveyed.

[0023] According to the fourth aspect, the accumulation profile of the waste powder in the recovery container can be flattened.

[0024] According to the fifth aspect, the accumulation profile of the waste powder in the recovery container can be flattened.

[0025] According to the sixth aspect, accumulation of waste powder near the delivery port can be promoted.

[0026] According to the seventh aspect, the transport unit can be reduced in weight.

[0027] According to the eighth aspect, the transport unit can be reduced in weight.

[0028] According to the ninth aspect, the height of the waste powder deposited in the second deposit profile can be detected.

[0029] According to the tenth aspect, it is possible to prevent the waste powder accumulated in the first accumulation profile from clogging the transfer port. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic cross-sectional view showing an example of a schematic structure of an image forming apparatus.

[0031] Figure 2 A diagram illustrating the configuration of a photoreceptor unit and a developing device.

[0032] Figure 3 It is a cross-sectional schematic diagram showing the structure of the cleaning device.

[0033] Figure 4 It is a side view showing the overall structure of the waste toner collecting device.

[0034] Figure 5 This is a diagram showing a waste toner collection path on the back side of the image forming apparatus.

[0035] Figure 6 FIG. 1 is a diagram showing a conveying auger of a waste toner collecting device.

[0036] Figure 7 A diagram illustrating the waste toner conveying operation of the conveying auger.

[0037] Figure 8 This is a diagram for explaining the relationship between the conveying auger and the accumulation profile of the waste powder stored in the recovery container.

[0038] Figure 9 This is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container and the position of the transport auger.

[0039] Figure 10 This is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container and the position of the transport auger.

[0040] Figure 11 This is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container and the position of the transport auger.

[0041] Figure 12 This is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container and the position of the transport auger.

[0042] Figure 13 This is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container and the position of the transport auger.

[0043] Figure 14 This is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container having the transport auger of Comparative Example 1 and the position of the transport auger.

[0044] Figure 15 This is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container having the transport auger of Comparative Example 2 and the position of the transport auger. DETAILED DESCRIPTION

[0045] Next, the present invention will be described in further detail with reference to the accompanying drawings by way of embodiments and specific examples, but the present invention is not limited to these embodiments and specific examples.

[0046] In the description using the following drawings, it should be noted that the drawings are schematic and the ratios of dimensions and the like may differ from actual ones. For ease of understanding, illustration of components other than those necessary for the description is omitted as appropriate.

[0047] In order to facilitate understanding of the following description, in the drawings, the front-back direction is referred to as the X-axis direction, the left-right direction is referred to as the Y-axis direction, and the up-down direction is referred to as the Z-axis direction.

[0048] (1) Overall structure and operation of image forming apparatus

[0049] (1.1) Overall structure of image forming apparatus

[0050] Figure 1 It is a schematic cross-sectional view showing an example of a schematic configuration of the image forming apparatus 1 according to the present embodiment.

[0051] The image forming apparatus 1 includes an image forming unit 10 , a paper feeder 20 installed below the image forming unit 10 , and a paper discharger 30 provided at one end of the image forming unit 10 for discharging printed paper.

[0052] The image forming unit 10 is configured to include a system control device (not shown), an exposure device 12, a photosensitive unit 13 as an image forming unit, a developing device 14, a transfer device 15, paper conveying devices 16a, 16b, 16c and a fixing device 17, and forms a colorant image on a recording medium fed from a paper feeding device 20.

[0053] The paper feeding device 20 supplies recording media to the image forming unit 10. Specifically, the paper feeding device 20 includes a plurality of paper loading sections 21 and 22 for storing recording media of different types (e.g., material, thickness, paper size, and paper texture), and supplies the image forming unit 10 with a recording medium fed from any of the plurality of paper loading sections 21 and 22.

[0054] The paper discharge unit 30 discharges the recording medium on which the image has been output by the image forming unit 10. To this end, the paper discharge unit 30 includes a paper storage portion for discharging the recording medium after image output. Furthermore, the paper discharge unit 30 may also perform post-processing such as cutting or stapling the stack of paper output from the image forming unit 10.

[0055] (1.2) Structure and Operation of Image Forming Unit

[0056] In an image forming device 1 having such a structure, the recording medium fed out from the paper loading sections 21, 22 is fed into the image forming section 10 in correspondence with the timing of image formation. The paper loading sections 21, 22 refer to the paper loading sections 21, 22 designated for each sheet of paper to be printed in a print job.

[0057] The photoreceptor units 13 (Y, M, C, K: hereinafter referred to as the photoreceptor units 13 unless otherwise specified) include rotatably driven photoreceptor drums 31, each of which is arranged below the exposure device 12. Along the rotational direction of the photoreceptor drums 31 are arranged the charger 32, the exposure device 12, the developing device 14, the primary transfer roller 52, and the cleaning device 33.

[0058] The developing device 14 includes a developing housing 41 that contains a developer. A developing roller 42 is disposed within the developing housing 41 and faces the photosensitive drum 31. A developer having a limited layer thickness is supplied to the developing roller 42, forming a toner image on the photosensitive drum 31.

[0059] Each developing device 14 (Y, M, C, K: hereinafter referred to as the developing device 14 unless otherwise required) is constructed in roughly the same manner except for the developer contained in the developing housing 41, and forms yellow (Y), magenta (M), cyan (C), and black (K) colorant images, respectively.

[0060] A replaceable toner cartridge T containing developer (toner containing carrier) is mounted above the developing device 14. A toner cartridge guide (not shown) is provided to supply developer from each toner cartridge T (Y, M, C, K) to the developing device 14.

[0061] The surface of the rotating photosensitive drum 31 is charged by the charger 32, and an electrostatic latent image is formed by latent image forming light emitted from the exposure device 12. The electrostatic latent image formed on the photosensitive drum 31 is developed into a toner image by the developing roller 42.

[0062] The transfer device 15 is composed of an intermediate transfer belt 51 as an image holder for the colorant images of various colors formed on the photosensitive drums 131 of the photosensitive units 13, which are multi-transferred, a primary transfer roller 52 that sequentially transfers (primary transfer) the colorant images of various colors formed by the photosensitive units 13 onto the intermediate transfer belt 51, and a secondary transfer roller 53 that transfers (secondary transfer) the colorant images of various colors transferred overlappingly onto the intermediate transfer belt 51 together onto a recording medium.

[0063] The color toner images formed on the photosensitive drum 31 of each photosensitive unit 13 are electrostatically transferred (primary transfer) in sequence to the intermediate transfer belt 51 by the primary transfer roller 52 to which a prescribed transfer voltage is applied, thereby forming an overlapping colorant image formed by overlapping color toners of each color. The prescribed transfer voltage is applied from a power supply device (not shown) controlled by a system control device.

[0064] The superimposed toner images on the intermediate transfer belt 51 are conveyed to the secondary transfer portion TR as the intermediate transfer belt 51 moves. In the secondary transfer portion TR, the secondary transfer roller 53 is arranged in pressure contact with the backup roller 65 with the intermediate transfer belt 51 interposed therebetween.

[0065] When the superimposed toner images are conveyed to the secondary transfer section TR, paper is fed from the paper feed device 20 to the secondary transfer section TR at that time. Then, a predetermined secondary transfer voltage is applied from a power supply device controlled by the system control device to the backup roller 65, which faces the secondary transfer roller 53 across the intermediate transfer belt 51. This transfers the multiple toner images on the intermediate transfer belt 51 onto the paper simultaneously.

[0066] The residual toner on the intermediate transfer belt 51 after the multiple toner images have been transferred is removed by the cleaning device 70 and collected in the waste toner collecting device 100 .

[0067] The residual toner on the surface of the photosensitive drum 31 is removed by the cleaning device 33 and recovered in the waste toner recovery device 100. The surface of the photosensitive drum 31 is charged again by the charger 32.

[0068] The fixing device 17 includes an endless fixing belt 17a that rotates in one direction and a pressure roller 17b that contacts the peripheral surface of the fixing belt 17a and rotates in one direction. A fixing area is formed by pressure contact between the fixing belt 17a and the pressure roller 17b.

[0069] The recording medium to which the toner image has been transferred in the transfer device 15 is conveyed via the paper conveying device 16a to the fixing area of ​​the fixing device 17, while the toner image is not yet fixed. The toner image on the recording medium conveyed to the fixing device 17 is fixed by the action of heat and pressure by a pair of fixing belts 17a and a pressure roller 17b.

[0070] The recording medium on which fixing has been completed is fed to the paper discharge unit 30 via the paper transport device 16 b .

[0071] When outputting images on both sides of a recording medium, the front and back sides of the recording medium are reversed by the paper transport device 16c and fed again to the secondary transfer section TR in the image forming section 10. After the toner image is transferred and the transferred image is fixed, the recording medium is fed to the paper discharge section 30. The recording medium fed to the paper discharge section 30 undergoes subsequent processing such as cutting or stapling (stapling) as needed, and is then discharged to the paper discharge storage section.

[0072] (2) Waste toner recovery path

[0073] Figure 2 1 is a diagram illustrating the structure of the photosensitive body unit 13 and the developing device 14. Figure 3 is a schematic cross-sectional view showing the structure of the cleaning device, Figure 4 is a side view showing the overall structure of the waste toner recovery device 100, Figure 5 FIG. 1 is a diagram showing a waste toner collection path on the back side of the image forming apparatus 1. Figure 6FIG. 1 is a diagram showing the conveying auger 110 of the waste toner collecting device 100 .

[0074] Hereinafter, the configuration of the waste toner collection path and the waste toner collection device in the image forming apparatus 1 will be described with reference to the drawings.

[0075] (2.1) Discharge of waste toner and waste developer

[0076] After the toner image is primarily transferred to the intermediate transfer belt 51, Figure 2 The cleaning device 33 of the photoreceptor unit 13 shown cleans the waste powder collected on the photoreceptor drum 31. The waste powder includes residual developer (toner and external additives) and foreign matter such as paper dust attached to the photoreceptor drum 31 from the recording medium.

[0077] The cleaning brush 33A is in contact with the surface of the photosensitive drum 31. Figure 2 The photosensitive drum 31 rotates counterclockwise as shown by the arrow B in the middle (the photosensitive drum 31 rotates counterclockwise as shown by the arrow B in the middle Figure 2 The drum 31 is rotated clockwise as shown by the arrow A in the middle), so that the recovered matter on the photosensitive drum 31 floats up so that it can be easily removed.

[0078] The cleaning blade 33B scrapes off the recovered matter on the photoconductive drum 31 that has been lifted up by the cleaning brush 33A, thereby removing the recovered matter.

[0079] Furthermore, the toner recovery auger 33C is provided below the cleaning device 33 and rotates along the rotation axis toward the outside of the cleaning device 33 (the waste toner conveying portion 80, see FIG. Figure 4 ) transports the toner removed by the cleaning blade 33B and the toner removed from the cleaning brush 33A by the flicker bar 33Aa and stored in the cleaning device 33.

[0080] In the developing device 14, the developer (toner containing a carrier) supplied to the developing housing 41 is stirred by the stirring auger 43 in the developing housing 41 and is then conveyed to the developing roller 42 by the supply auger 44. A portion of the developer is then discharged as waste powder (hereinafter referred to as developer) to the outside of the developing device 14 (the waste toner conveying section 80, see FIG. 1 ). Figure 3 ).

[0081] In this manner, by supplying new developer into the developing housing 41 and discharging excess developer, it is possible to perform development using the newly supplied developer without continuously using the developer containing the deteriorated carrier.

[0082] (2.2) Recovering Waste Toner from the Transfer Device 15

[0083] A cleaning device 70 is provided on the intermediate transfer belt 51 of the transfer device 15 at a location downstream of the secondary transfer portion TR in the moving direction of the intermediate transfer belt 51 .

[0084] like Figure 3 As shown, the cleaning device 70 is composed of a housing 71, a cleaning brush 72, a cleaning blade 73, a waste toner conveying auger 74 and a film 75, and collects the untransferred toner remaining on the intermediate transfer belt 51 after the secondary transfer.

[0085] The cleaning brush 72 is in contact with the surface of the intermediate transfer belt 51. Figure 3 The intermediate transfer belt 51 rotates clockwise as shown by the arrow B in the middle (the intermediate transfer belt 51 rotates clockwise as shown by the arrow B in the middle Figure 3 The intermediate transfer belt 51 moves as shown by the arrow A in the middle, so that the recovered materials (residual toner and paper dust, etc.) on the intermediate transfer belt 51 float up to facilitate their removal.

[0086] The cleaning blade 73 scrapes off the recovered matter on the intermediate transfer belt 51 that has floated up by the cleaning brush 72 , and removes the recovered matter.

[0087] A conveying path 71a is formed in the housing 71. The conveying path 71a is formed to intersect the moving direction of the intermediate transfer belt 51 and extends from the front side to the back side (Y direction) of the apparatus body. A waste toner conveying auger 74 is disposed inside the conveying path 71a.

[0088] The waste toner conveying auger 74 conveys the recovered material removed from the intermediate transfer belt 51 by the cleaning brush 72 and the cleaning blade 73 toward a waste toner dropping path 220 to be described later.

[0089] (2.3) Waste toner conveying unit

[0090] A waste toner conveying unit 80 is provided on the rear side of the image forming apparatus 1 . The waste toner conveying unit 80 conveys waste toner and waste developer (hereinafter referred to as waste powder) as recovered materials collected from the photoreceptor unit 13 and the developing device 14 .

[0091] The waste toner conveying section 80 is configured to extend horizontally (in the X direction) along each photoreceptor unit 13 (Y, M, C, K) and each developing device 14 (Y, M, C, K), and each photoreceptor unit 13 (Y, M, C, K) and each developing device 14 (Y, M, C, K) are configured along the intermediate transfer belt 51.

[0092] The waste toner conveying unit 80 is composed of a conveying pipe 81 which is hollow as a whole and contains waste powder inside, and a waste toner conveying auger 82 which conveys the waste powder.

[0093] A receiving port 81a and a receiving port 81b are formed on the conveying pipe 81, wherein the receiving port 81a receives the waste colorant discharged from the colorant recovery screw conveyor 33C (Y, M, C, K) of each photosensitive unit 13 (Y, M, C, K), and the receiving port 81b receives the developer of each developing device 14 (Y, M, C, K).

[0094] The waste toner conveying auger 82 has a spiral blade formed around a rotation axis, receives a rotational force from a driving source (not shown) and rotates along the inner wall of the conveying pipe 81, thereby conveying the waste toner (received from the receiving ports 81a and 81b) in the conveying pipe 81. Figure 5 X direction: refer to arrow R1).

[0095] The waste powder conveyed by the waste toner conveying auger 82 in the conveying pipe 81 falls toward the waste toner falling path 90 when reaching the discharge port 81 c .

[0096] (2.4) Waste toner drop path

[0097] A waste toner drop path 90 is provided on the rear side of the image forming apparatus 1 . The waste toner drop path 90 receives waste powder discharged from the waste toner conveying unit 80 and the cleaning device 70 and drops the waste powder while stirring it toward the waste toner collecting device 100 (−Z direction).

[0098] The waste toner drop path 90 is composed of the following components: a tubular component 91; a vibrator 92, which moves forward and backward in the internal space of the tubular component 91 in a manner of vibrating in the up and down directions, so that the waste powder attached to the inner wall is shattered; and a driving source (not shown) which transmits the driving force for moving the vibrator 92 forward and backward. The waste toner drop path 90 is arranged in a substantially vertical direction relative to the discharge outlet 81c of the waste toner conveying section 80 and the discharge outlet 71B of the cleaning device 70.

[0099] The waste toner drop path 90 causes the waste powder received from the waste toner conveying unit 80 and the cleaning device 70 to drop toward the waste toner collecting device 100 while being vibrated by the vibrator 92 ( Figure 6 Refer to arrow R).

[0100] (2.5) Waste toner recovery device

[0101] The waste toner recovery device 100 includes a recovery container 101, which has a space inside for storing waste developer and waste toner and other waste powders. A handle 102 is formed on the front surface side (-Y direction) of the recovery container 101, and the handle 102 is used to move the device body (refer to FIG. Figure 1) When the waste toner collecting device 100 is attached and detached. In addition, a handle (recess) 103 is formed on the upper side of the center portion of the collecting container 101 to facilitate carrying the waste toner collecting device 100.

[0102] An insertion port 104 is provided on the upper side of the back side (Y direction) of the recovery container 101. The insertion port 104 can be used to receive the transport pipe 93 (see FIG. Figure 4 ) is inserted. A rotatable conveying auger 94 is provided within a conveying pipe 93 of the waste toner drop path 90. Furthermore, the conveying pipe 93 and the conveying auger 94 are used to convey the waste powder that falls from the waste toner drop path 90. A discharge port 95 is provided at the lower end of the conveying pipe 93 for discharging the conveyed waste powder.

[0103] A transfer port 105 is provided at the lower inner portion of the insertion port 104 of the recovery container 101. This transfer port 105 opens upward and receives waste powder discharged from the discharge port 95 of the conveying tube 93. Furthermore, a shutter (not shown) is provided within the insertion port 104. This shutter opens the transfer port 105 when the conveying tube 93 is inserted into the insertion port 104 and closes the transfer port 105 when the conveying tube 93 is removed from the insertion port 104 (when the recovery device 60 is removed from the device body). The shutter is biased toward the rear side (Y direction) by a coil spring (not shown) and is pressed inward by the conveying tube 93, thereby opening the transfer port 105.

[0104] A rotatably mounted coupling member 107 is mounted on the substantially central side of the back side (Y direction) of the recovery container 101 . A transport auger 110 as a transport unit is mounted on the coupling member 107 and extends within the recovery container 101 .

[0105] The conveying auger 110 is made of a synthetic resin such as POM. A spiral blade 112 is integrally formed on a shaft 111 with a gap therebetween. This makes the conveying auger 110 lighter than metal. The conveying auger 110 thus formed rotates in conjunction with the rotation of the coupling member 107, which is driven by a drive system (not shown) of the device body.

[0106] In addition, in this embodiment, the conveying screw auger 110 extends to the substantially central portion of the recovery container 101, and the end portion not attached to the coupling member 107 becomes a free end. Figure 5 As shown by the arrow in , the conveying auger 110 is cantilever-supported in a manner that the head thereof can swing freely.

[0107] Furthermore, the spiral blade 112 of the conveying auger 110 includes a first conveying portion 112A that conveys with a first conveying force and a second conveying portion 112B that conveys with a second conveying force that is smaller than the first conveying force. Figure 6 As shown, the pitch of the spiral blades 112 of the first conveying portion 112A (see Figure 6 The pitch (P1, P2) of the spiral blades 112 of the second conveying section 112B is wider than the pitch (P1) of the first conveying section 112A. More specifically, the pitch (P2) of the spiral blades 112 is at least twice as wide as the pitch (P1) of the second conveying section 112B. The functions of the first conveying section 112A and the second conveying section 112B will be described later.

[0108] A fullness detection sensor SNR (not shown) serving as a detection unit is mounted on the device body, corresponding to the side of the recovery container 101. This fullness detection sensor SNR detects whether the waste powder stored in the recovery container 101 has reached a predetermined height. In this embodiment, the fullness detection sensor SNR is an optical sensor that can directly detect the accumulated amount. A detection window 108 is provided in the recovery container 101, through which the optical detection sensor SNR detects the accumulated amount. The fullness detection sensor SNR is not limited to an optical sensor; a magnetic permeability sensor that utilizes the magnetism of the carrier contained in the waste developer to detect the level may also be used.

[0109] (3) Waste powder recovery

[0110] Figure 7 1 is a diagram for explaining the waste toner conveying function of the conveying auger 110. Figure 8 1 is a diagram for explaining the relationship between the conveying auger 110 and the accumulation profile of the waste powder stored in the recovery container 101. Figures 9 to 13 1 is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container 101 and the position of the conveying auger 110. Figure 14 1 is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container 101 having the transport auger 110A of Comparative Example 1 and the position of the transport auger 110A. Figure 15 This is a diagram for explaining the relationship between the amount of waste powder stored in the recovery container 101 having the transport auger 110B of Comparative Example 2 and the position of the transport auger 110B.

[0111] Hereinafter, the collection of waste powder in the waste toner collecting device 100 will be described with reference to the drawings.

[0112] (3.1) Conveying function of the conveying auger

[0113] like Figure 7 As shown in (a) and (b), it is known that the spiral blades 112 of the conveying screw conveyor 110 vary in magnitude of the axial conveying force F1 and the radial discharge force F2 depending on the pitch P thereof. Figure 7 As shown in (a), when the pitch P1 of the spiral blades is wide, the surface 112Aa of the spiral blades tends to be at an acute angle ( Figure 7 (b) is θ1), so the conveying force F1 is small, and the discharge force F2 in the direction intersecting the relative movement direction of the spiral blade becomes large. On the other hand, Figure 7 As shown in (b), when the pitch P2 of the spiral blades is narrow, the surface 112Ba of the spiral blades tends to be obtuse angled with respect to the axial direction ( Figure 7 θ2 in (a), the conveying force F1 is large, and the discharge force F2 in the direction intersecting the relative movement direction of the spiral blade is small.

[0114] And, as Figure 8 As shown, in the conveying auger 110, the first conveying portion 112A having a wide pitch P1 of spiral blades is provided within a range including a position below the carrying-in port 105 ( Figure 8 A second conveying portion 112B having a narrower pitch P2 of spiral blades is provided at the distal end of the conveying auger 110 following the first conveying portion 112A.

[0115] As a result, the first conveying portion 112A having a wider pitch P1 between spiral blades has a greater effect of discharging waste powder in a direction intersecting the axial direction, thereby causing the waste powder to accumulate on the back side (Y direction) of the recovery container 101, and the second conveying portion 112B having a narrower pitch P2 between spiral blades has a greater effect of conveying waste powder in the axial direction, thereby conveying the waste powder toward the front surface side (-Y direction) of the recovery container 101 and causing it to accumulate.

[0116] Therefore, if Figure 8 As schematically shown in FIG, the first conveying portion 112A of the conveying auger 110 deposits the waste powder dropped from the inlet 105 on the back side (Y direction) of the recovery container 101 in a first accumulation profile ( Figure 8 In addition, the second conveying unit 112B conveys the waste powder dropped from the inlet 105 toward the front surface side (-Y direction) of the recovery container 101 and stacks it in the second stacking profile ( Figure 8 (indicated by double-dashed lines in the figure) accumulation.

[0117] In this way, the conveying screw conveyor 110 has a first conveying part 112A that stacks the waste powder received from the import port 105 in a first stacking profile, and a second conveying part 112B that stacks the waste powder received from the import port 105 in a second stacking profile. By appropriately changing the respective spacings P1 and P2 of the first conveying part 112A and the second conveying part 112B, the first stacking profile and the second stacking profile can be combined to maximize the storage capacity of the recovery container 101.

[0118] (3.2) Waste powder recovery

[0119] Next, refer to Figures 9 to 15 , the waste powder recovery operation in the waste toner recovery device 100 will be described.

[0120] Figure 14 The waste powder collection state in the collection container 101 of the transport auger 110A of Comparative Example 1 is shown. The spiral blades 112 of the transport auger 110A are formed with a uniform pitch from the base end to the free end. Specifically, the spiral blades have a wide pitch P1 from the base end to the tip end, similar to the first transport portion 112A of the transport auger 110 of this embodiment.

[0121] When waste powder is loaded from the loading port 105 into the recovery container 101 equipped with such a conveying auger 110A, the waste powder first accumulates on the bottom (the bottom of the back side) of the recovery container 101 directly below the loading port 105. Then, when a certain amount of waste powder accumulates in the recovery container 101, the waste powder on the upper side is conveyed toward the front side (-Y direction) of the recovery container 101 by the rotating conveying auger 110A, and is also accumulated on the front side (-Y direction) of the recovery container 101.

[0122] Then, the conveying auger 110A is lifted up around the mounting position of the coupling member 107 due to the pressure from the waste powder accumulated in the recovery container 101, and moves upward. Figure 14 At the position shown, the waste powder is transported toward the front surface side (−Y direction) of the recovery container 101 and accumulated in the recovery container 101 .

[0123] Here, the spiral blades 112 of the conveying auger 110A are formed with a uniform, wide pitch P1 from the base end to the free end. Therefore, the axial conveying force F1 is relatively small compared to the discharge force F2 in the direction intersecting the axial direction. Furthermore, the waste powder accumulates on the upper surface of the recovery container 101 as a first accumulation profile on the back side (Y direction) of the recovery container 101, but is not sufficiently accumulated as a second accumulation profile on the front side (-Y direction) of the recovery container 101. Consequently, the waste powder storage capacity of the recovery container 101 cannot be maximized.

[0124] Figure 15 The waste powder storage state in the collection container 101 with the transport auger 110B of Comparative Example 2 is shown. The spiral blades 112 of the transport auger 110B are formed with a uniform pitch from the base end to the free end. Specifically, the spiral blades have a narrower pitch P2 from the base end to the tip end, similar to the second transport portion 112B of the transport auger 110 in this embodiment.

[0125] When waste powder is loaded from the loading port 105 into the recovery container 101 equipped with such a conveying auger 110B, the waste powder first accumulates on the bottom (the bottom of the back side) of the recovery container 101 directly below the loading port 105. Then, when a certain amount of waste powder accumulates in the recovery container 101, the waste powder on the upper side is conveyed toward the front side (-Y direction) of the recovery container 101 by the rotating conveying auger 110B, and is also accumulated on the front side (-Y direction) of the recovery container 101.

[0126] The spiral blades 112 of the conveying auger 110B are formed with a uniform, narrow pitch P2 from the base end to the free end. Therefore, the conveying force F1 in the axial direction is greater than the discharge force F2 in the direction intersecting the axial direction. Consequently, the waste powder is sufficiently accumulated on the front surface (-Y direction) of the recovery container 101 as the second accumulation profile. However, it is not sufficiently accumulated on the upper surface of the recovery container 101 as the first accumulation profile on the back side (Y direction) of the recovery container 101, resulting in failure to maximize the waste powder storage capacity.

[0127] Figure 9 The figure shows the initial stage, i.e., the state at which waste powder begins to be collected in the collection container 101. At this time, the tip (free end) of the conveying auger 110 hangs downward due to its own weight and adheres to the bottom of the collection container 101. The waste powder brought into the collection container 101 through the inlet 105 first accumulates at the bottom (the back side) of the collection container 101 directly below the inlet 105.

[0128] When a certain amount of waste powder accumulates in the recovery container 101 , the waste powder on the upper side is conveyed toward the front side (−Y direction) of the recovery container 101 by the rotating conveying auger 110 . Figure 10 The status at this time is shown. Figure 10 By conveying the waste powder using the conveying auger 110, the height of the waste powder in the recovery container 101 is made uniform. In addition, by conveying the waste powder in the recovery container 101, the bulk density of the waste powder can be increased.

[0129] Furthermore, since the conveying screw auger 110 is subjected to pressure from the waste powder accumulated in the recovery container 101, the conveying screw auger 110 is lifted up with respect to the mounting position of the coupling member 107 as the center. Figure 9 Specifically, the transport auger 110 is moved to an upper position by the swinging of the transport auger 110 so that the transport auger 110 is positioned at substantially the same angle as the upper surface of the waste powder accumulated in the recovery container 101 .

[0130] Figure 11 The waste powder is further conveyed into the recovery container 101. At this time, the conveying auger 110 moves to the upper surface of the accumulated waste powder, which becomes substantially horizontal, and the waste powder begins to accumulate in the second accumulation profile in the recovery container 101.

[0131] Figure 12 The waste powder is further conveyed into the collection container 101, and the collection container 101 is nearly full. At this point, because the conveying auger 110 has moved to the upper surface of the accumulated waste powder, the free end portion is higher than the coupling member 107. Within the collection container 101, the waste powder is accumulated in the first accumulation profile on the back side (Y direction) of the collection container 101. The waste powder is then conveyed by the second conveying portion 112B of the conveying auger 110 toward the front side (-Y direction) of the collection container 101, where it is accumulated in the second accumulation profile.

[0132] Figure 13The waste powder is further conveyed into the recovery container 101, and the free end of the conveying screw 110 swings to a position in contact with the upper surface of the recovery container 101. When the free end of the conveying screw 110 contacts the upper surface of the recovery container 101, the conveying screw 110 is double-supported between the free end and the base end mounted on the coupling member 107, and the conveying force of the spiral blade of the second conveying portion 112B increases. As a result, the waste powder further accumulates on the front surface side (-Y direction) of the recovery container 101, filling the detection window 108. As a result, the waste powder is roughly evenly stored on the upper surface of the recovery container 101 from the back side (Y direction) to the front side (-Y direction), and fullness is detected.

[0133] Thus, in this embodiment, the conveying auger 110 is swingably arranged on the coupling member 107, and the coupling member 107 is rotatably attached to the recovery container 101. Thus, the conveying auger 110 can follow the accumulation height of the waste powder in the recovery container 101 and move to a height equal to or slightly higher than the accumulation height of the waste powder.

[0134] The spiral blade of the conveying auger 110 includes a first conveying portion 112A that conveys with a first conveying force and a second conveying portion 112B that conveys with a second conveying force that is smaller than the first conveying force. Thus, the first conveying portion 112A deposits the waste powder received from the delivery port 105 at a first accumulation profile, while the second conveying portion 112B deposits the waste powder at a second accumulation profile while conveying the waste powder toward the front surface (-Y direction) of the recovery container 101. This maximizes the amount of waste powder stored in the recovery container 101.

Claims

1. A waste toner recovery device comprising: a recovery container having a delivery port for receiving waste powder, the delivery port receiving waste powder including either or both of used toner and developer discharged from the image forming unit; and A conveying unit, the base end of which is cantilevered and supported inside the recovery container so that the conveying unit can swing freely, comprising a first conveying portion for conveying the received waste powder with a first conveying force inside the recovery container and stacking it at a first stacking profile, and a second conveying portion for conveying the waste powder with a second conveying force smaller than the first conveying force and stacking it at a second stacking profile higher than the first stacking profile. As the waste powder accumulates, when the free end of the conveying unit contacts the upper surface of the recovery container, the conveying unit enters a double-supported state in which both the base end and the free end are supported, and the conveying force of the second conveying unit increases.

2. The waste toner recovery device according to claim 1, wherein: The conveying unit includes a spiral blade and is driven to rotate to convey the waste powder.

3. The waste toner recovery device according to claim 2, wherein: The pitch of the spiral blades of the first conveying unit is wider than the pitch of the spiral blades of the second conveying unit.

4. The waste toner recovery device according to claim 3, wherein: The pitch of the spiral blades of the first conveying portion is at least twice as wide as the pitch of the spiral blades of the second conveying portion.

5. The waste toner recovery device according to any one of claims 1 to 4, wherein: The first transport portion is formed within a range from the base end of the transport unit supported by the cantilever to a position below the carry-in port.

6. The waste toner recovery device according to claim 2, wherein: The conveying unit includes a shaft, and the spiral blade is integrally formed with the shaft with a gap therebetween.

7. The waste toner recovery device according to any one of claims 1 to 4, wherein: The conveying unit is formed using synthetic resin.

8. The waste toner recovery device according to claim 1, wherein: The waste toner collecting device further includes a detection unit configured to detect whether the waste powder accumulated in the second accumulation profile in the collection container has reached a predetermined height.

9. The waste toner recovery device according to claim 8, wherein: The detection unit is disposed at a height at which the waste powder reaches when the recovery container is filled with the waste powder, and the height at which the waste powder reaches when the waste powder accumulated in the first accumulation profile reaches the transfer port.

10. An image forming apparatus comprising: a first conveying unit that conveys waste powder collected from an image forming unit that forms a toner image; and A second conveying unit is configured to convey the waste powder so that the waste powder falls toward the waste toner collecting device according to any one of claims 1 to 9.

Images