JP2017053936A - Developing device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a waste developer from being dropped out of a conveying path while reducing cost and space.SOLUTION: A developing device 4 comprises: a conveying tube 440 that stores a developer and includes a discharge port 426 discharging the developer to the downstream of a developer conveying direction W; a stirring and conveying member 420 that is arranged inside the conveying tube 440 and conveys the developer through a rotational operation; and a shutter member 430 that is provided in an outer peripheral surface of the conveying tube 440 to open/close the discharge port 426 according to an attachment/detachment operation to/from a recovery part 200. The conveying tube 440 includes a recessed part 428 in which the conveying tube 440 is recessed in a peripheral part of the discharge port 426 on the downstream in the developer conveying direction W. The recessed part 428 has a function to prevent a waste developer from being dropped out of a conveying path during an operation to close the shutter member 430.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a developing device and an image forming apparatus.

  Conventionally, image forming apparatuses such as printers and copiers employing an electrophotographic system have been widely used. In an image forming apparatus, generally, a latent image carried on a photoconductor is developed into a toner image by a developing device, the developed toner image is transferred onto a sheet via an intermediate transfer belt, and then the transferred toner image is fixed to a fixing device. The image forming process is performed through a series of processes such as fixing to a sheet.

  As a developing method for forming a toner image on a photoreceptor, there is a two-component developing method using toner and a carrier as main components of a developer. In the development method of the two-component development method, the toner is consumed by the development process, while the carrier is not consumed and remains in the developing device. Therefore, mechanical stress and thermal stress due to contact with the toner are accumulated in the carrier. Therefore, there is a trickle development system in which a carrier is periodically replaced by discharging a developer containing a deteriorated carrier (hereinafter referred to as a waste developer) while supplying a new developer (toner and carrier). Widely adopted.

  FIG. 10 shows an example of the configuration of a conventional developing device 500. As illustrated in FIG. 10, the developing device 500 includes a transport pipe 510 that stores the developer, a transport member 520 that stirs and transports the developer, a discharge port 530 that discharges the waste developer A, and a discharge port. And a shutter member 540 that opens and closes 530.

  When the developing device 500 is attached to the collection unit that collects the waste developer A, the shutter member 540 is opened, the discharge port 530 is opened (exposed), and the waste developer A is discharged from the discharge port 530 to the collection unit. At this time, if the discharge amount of the waste developer A is small, the waste developer A is discharged in the vertical direction, and if the discharge amount of the waste developer A is large, it is also discharged downstream in the transport direction W of the developer. In such a case, the waste developer A adheres to the vicinity of the discharge port 530 (shaded portion B), and the attached waste developer A is scraped off during the closing operation of the shutter member 540 and falls into the transport path. There was a case.

  Therefore, various techniques have been proposed to deal with the problems described above. For example, Patent Document 1 discloses an image forming apparatus that includes a wiping member that wipes off toner adhering to the outer peripheral surface of a shutter member, and a cleaning member that cleans the contact surface of the wiping member. Patent Document 2 discloses an image forming apparatus including a cleaning member that performs cleaning by contacting a toner container. Patent Document 3 discloses an image forming apparatus including a cleaning member that performs cleaning by contacting a toner storage container when the toner storage container is attached or detached. Patent Document 4 discloses a toner removing device including a cleaning member that removes toner adhering to a shutter member by rotation.

JP-A-2015-87447 JP 2013-167800 A JP 2014-21246 A JP-A-5-35093

  However, in the image forming apparatuses described in Patent Documents 1 to 4 described above, the developer attached near the discharge port is removed using a wiping member or a cleaning member that wipes off the toner. There is a problem that the cost is excessive. Furthermore, there is a problem that a space for installing a wiping member, a cleaning member, and the like is separately required, and the space of the apparatus cannot be saved.

  Accordingly, the present invention has been made in view of the above problems, and a developing device capable of preventing waste developer from falling off the conveyance path while reducing cost and saving space, and An object is to provide an image forming apparatus.

  In order to solve the above problems, a developing device according to the present invention is a developing device that can be attached to a collecting unit that collects a developer, and stores the developer and is downstream in the transport direction of the developer. A developing device main body having a discharge port for discharging the developer, a conveying member provided in the developing device main body for conveying the developer by a rotating operation, and provided on a peripheral surface of the developing device main body, A shutter member that opens and closes the discharge port in accordance with an attaching / detaching operation with respect to the collection unit, and the developing device main body has the developing device main body at a peripheral portion at least downstream of the discharge port in the developer transport direction. It has a depressed recess.

  An image forming apparatus according to the present invention includes the above developing device.

  According to the present invention, since the waste developer is attached to the concave portion provided in the peripheral portion of the discharge port, it is possible to prevent the waste developer from being scraped off by the closing operation of the shutter member. As a result, it is possible to prevent the waste developer from falling out of the conveyance path while reducing the cost and space.

1 is a diagram illustrating a configuration example of an image forming apparatus according to an embodiment of the present invention. It is sectional drawing which shows the structural example of a developing device. (A) is sectional drawing which shows the structural example of the side surface of the developing device in the state where the shutter member was closed, (B) is a figure which shows the principal part. (A) is sectional drawing which shows the structural example of the side surface of the developing device of the state in which the shutter member was opened, (B) is a figure which shows the principal part. It is sectional drawing which shows the structural example of the conveyance pipe of a developing device. It is sectional drawing which shows the state which mounted | wore the collection | recovery part with the image development apparatus. It is a figure which shows the modification of the recessed part of a developing device. It is a figure which shows the modification of the recessed part of a developing device. It is a figure which shows the modification of the conveying member of a developing device. It is a figure for demonstrating the problem of the conventional developing apparatus.

  Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, the dimension ratio of drawing is expanded on account of description and may differ from an actual ratio.

[Configuration Example of Image Forming Apparatus 100]
FIG. 1 shows an example of the configuration of an image forming apparatus 100 according to the present invention. As shown in FIG. 1, the image forming apparatus 100 is called a tandem type image forming apparatus, and includes an automatic document feeder 80 and an apparatus main body 102. The automatic document conveyance unit 80 is attached to the upper part of the apparatus main body 102 and sends out the paper set on the conveyance table to the image reading unit 90 of the apparatus main body 102 by a conveyance roller or the like.

  The apparatus main body 102 includes an operation display unit 70, an image reading unit 90, an image forming unit 10, an intermediate transfer belt 8, a paper feeding unit 20, a registration roller pair 32, a fixing unit 44, and automatic paper reverse conveyance. And a unit 60 (Auto Duplex Unit: hereinafter referred to as ADU).

  The operation display unit 70 includes a touch panel in which a display unit and an input unit are combined, and a plurality of operation keys including a start key and a determination key provided in a peripheral part of the touch panel. The operation display unit 70 displays a menu screen or the like on the screen, or receives information related to image forming conditions input by a touch operation on the menu screen or an operation of an operation key.

  The image reading unit 90 scans and exposes the document placed on the document table or the document transported by the automatic document transport unit 80 by the optical system of the scanning exposure device, and the image of the scanned document is CCD (Charge Coupled Device). ) Photoelectric conversion is performed by an image sensor to generate an image information signal. The image information signal is output to the image forming unit 10 after being subjected to analog processing, analog / digital (hereinafter referred to as A / D) conversion processing, pseudo correction, image compression processing, and the like by an image processing unit (not shown).

  The image forming unit 10 forms an image by electrophotography, and includes an image forming unit 10Y that forms a yellow (Y) image, an image forming unit 10M that forms a magenta (M) image, The image forming unit 10C forms a cyan (C) color image, and the image forming unit 10K forms a black (K) color image. In this example, common function names, for example, Y, M, C, and K indicating colors to be formed are added to the back of the reference numeral 10.

  The image forming unit 10Y includes a photosensitive drum 1Y, a charger 2Y, an exposure device (optical writing unit) 3Y, a developing device 4Y, and a cleaning unit 6Y arranged around the photosensitive drum 1Y. The image forming unit 10M includes a photosensitive drum 1M, a charger 2M, an exposure device 3M, a developing device 4M, and a cleaning unit 6M disposed around the photosensitive drum 1M. The image forming unit 10C includes a photosensitive drum 1C, a charger 2C, an exposure device 3C, a developing device 4C, and a cleaning unit 6C arranged around the photosensitive drum 1C. The image forming unit 10K includes a photosensitive drum 1K, a charger 2K, an exposure device 3K, a developing device 4K, and a cleaning unit 6K disposed around the photosensitive drum 1K.

  Respective photosensitive drums (image carriers) 1Y, 1M, 1C, and 1K in image forming units 10Y, 10M, 10C, and 10K, chargers 2Y, 2M, 2C, and 2K, exposure devices 3Y, 3M, 3C, and 3K, development The devices 4Y, 4M, 4C, and 4K, the cleaning units 6Y, 6M, 6C, and 6K, and the primary transfer rollers 7Y, 7M, 7C, and 7K have a common configuration. In the following description, Y, M, C, and K are not used unless particularly distinguished.

  The charger 2 charges the surface of the photosensitive drum 1 almost uniformly. The exposure device 3 is composed of, for example, an LPH (LED Print Head) having an LED array and an imaging lens, or a polygon mirror type laser exposure scanning device, and the photosensitive drum 1 is irradiated with laser light based on an image information signal. Scan to form an electrostatic latent image. The developing device 4 develops the electrostatic latent image formed on the photosensitive drum 1 with toner. As a result, a toner image which is a visible image is formed on the photosensitive drum 1.

  The intermediate transfer belt 8 is stretched by a plurality of rollers and is rotatably supported. Along with the rotation of the intermediate transfer belt 8, the primary transfer roller 7 and the photosensitive drum 1 rotate, and a predetermined voltage is applied between the primary transfer roller 7 and the photosensitive drum 1, whereby the photosensitive member. The toner image formed on the drum 1 is transferred onto the intermediate transfer belt 8 (primary transfer).

  The paper feed unit 20 has a plurality of paper feed trays 20A and 20B in which paper P such as A3 and A4 is accommodated. The paper P transported by the transport rollers 22, 24, 26, 28, etc. from the respective paper feed trays 20A, 20B is transported to the registration roller pair 32. Note that the number of paper feed trays is not limited to two. Further, a single or a plurality of large-capacity paper feeders that can accommodate a large-capacity paper P may be connected as necessary.

  The registration roller pair 32 corrects the bending (for example, skew) of the paper P with respect to the paper transport direction D by forming a loop by abutting the front end of the paper by the transport of the paper P by the loop roller pair 30. The paper P in which the bending of the paper P is corrected is conveyed to the secondary transfer roller 34 at a predetermined timing. In the secondary transfer roller 34, the Y, M, C, and K color toner images transferred onto the intermediate transfer belt 8 are collectively transferred onto the surface of the paper P conveyed by the resist roller pair 32 ( Secondary transfer). The second-transferred sheet P is conveyed to the fixing unit 44 on the downstream side in the sheet conveying direction D.

  The fixing unit 44 includes a pressure roller, a heating roller, a fixing belt, and the like. The fixing unit 44 fixes the toner image on the surface of the paper P to the paper P by performing pressure and heat treatment on the paper P on which the toner image has been transferred by the secondary transfer roller 34.

  The transport path switching unit 48 performs control to switch the transport path of the paper P to the paper discharge path side or the ADU 60 side based on the selected printing mode (single-sided printing mode, double-sided printing mode, etc.). The paper P on which single-sided printing has been completed in the single-sided printing mode or the paper P on which double-sided printing has been completed in the double-sided printing mode is discharged onto the paper discharge tray by the paper discharge roller 46.

  Further, when an image is formed on the back side of the paper P in the duplex printing mode, the paper P on which the image is formed on the front side is conveyed to the ADU 60 via the conveyance roller 62 and the like. In the switchback path of the ADU 60, the reverse rotation control of the ADU roller 64 causes the rear end of the paper P to be transported to the U-turn path section, and is reversed by the transport rollers 66 and 68 provided in the U-turn path section. In this state, the paper is fed again to the secondary transfer roller 34.

[Configuration Example of Developing Device 4]
FIG. 2 shows an example of the configuration of the developing device 4. The developing device 4 employs a trickle developing system that replenishes toner consumed in image formation and replaces the carrier in the developing device 4 little by little. As the trickle mechanism, a known circulation overflow type or liquid level overflow type can be applied. As shown in FIG. 2, the developing device 4 includes a developing device main body 400, a toner supply unit 404, a carrier supply unit 406, stirring and conveying members 410 and 420, and a developing roller 450.

  The developing device main body 400 is a container for storing a two-component developer composed of toner and carrier. The developing device main body 400 has a replenishment port 404a for replenishing toner and a replenishment port 406a for replenishing carriers above the developer stirring path 412. The toner replenished from the toner supply unit 404 is supplied into the developing device main body 400 through the replenishing port 404a. The carrier supplied from the carrier supply unit 406 is supplied into the developing device main body 400 through the supply port 406a.

  The developing device main body 400 is partitioned by a partition wall 402 into a developer stirring path 412 and a developer supply path 422. The developer stirring path 412 and the developer supply path 422 communicate with each other at the end in the path direction so that the developer can circulate (not shown). Further, the developer conveyance direction of the developer stirring path 412 and the developer conveyance direction of the developer supply path 422 are opposite to each other.

  The agitating / conveying member 410 is constituted by a screw and is disposed in the developer agitating path 412. The agitating and conveying member 410 is rotated by driving of a drive motor (not shown), and conveys the developer in one direction while agitating the developer. The developer transported by the stirring transport member 410 is transported to the developer supply path 422.

  The agitating / conveying member 420 is constituted by a screw and is disposed in the developer supply path 422. The agitating / conveying member 420 is rotated by driving of a drive motor (not shown) to convey the developer in one direction while stirring the developer, and supplies the developer to the developing roller 450 in this conveying process. Further, the waste developer that has become surplus as the toner is supplied from the toner supply unit passes through a discharge port 426 formed on the downstream side in the transport direction of the developer supply path 422 of the developing device main body 400. It is discharged to a collection unit to be described later. The agitating and conveying member 420 is an example of a conveying member in the present disclosure.

  The developing roller 450 is a so-called magnet roller having a magnet body that is fixed so as not to rotate and a cylindrical conveyance sleeve that is rotatably arranged around the magnet body. The developing roller 450 supplies a developer to the photosensitive drum 1 on which the electrostatic latent image is formed.

[Configuration example of main part of developing device 4]
FIG. 3A is an example of the configuration of the developing device 4 in a state where the shutter member 430 is closed, and FIG. 3B is a diagram illustrating the main part thereof. FIG. 4A is an example of the configuration of the developing device 4 in a state where the shutter member 430 is opened, and FIG. 4B is a diagram illustrating the main part thereof. FIG. 5 shows an example of a cross-sectional configuration of the transport pipe 440 of the developing device 4. In this example, the downstream side in the developer transport direction W is referred to as the leading end of the transport pipe 440, and the upstream side in the developer transport direction W is referred to as the rear end of the transport pipe 440.

  As shown in FIG. 3A, FIG. 3B, FIG. 4A, and FIG. 4B, the developing device main body 400 includes a transport pipe 440, an agitation transport member 420, a support portion 424, A discharge port 426, a recess 428, a shutter member 430, and seal members 432 and 434 are provided.

  The transport pipe 440 constitutes a part (developer supply path 422) of the developing device main body 400 shown in FIG. 2, for example, and is made of a cylindrical shape (pipe shape) and an uncharged material. The transport pipe 440 is attached to and detached from the insertion port 212 of the collection unit 200 that collects the waste developer described later. Further, the transport pipe 440 extends to the downstream side in the developer transport direction W from the discharge port 426. A portion extending from the discharge port 426 of the transport pipe 440 functions as a guide for the shutter member 430 rather than a portion for transporting the developer.

  The agitating and conveying member 420 is disposed inside the conveying tube 440, and has a shaft 420a extending along the developer supply path 422 and a blade 420b formed in a spiral shape on the shaft 420a. The shaft 420a extends from the discharge port 426 to the downstream portion in the developer transport direction W, and the tip of the shaft 420a is rotatably supported by the support portion 424. The blade 420 b is formed on the upstream side in the developer transport direction W from the discharge port 426.

  The discharge port 426 discharges the waste developer to the outside (collecting unit 200), and is on the lower surface side of the transport pipe 440 and transports the developer as shown in FIG. 3A and FIG. It is formed at the most downstream part in the direction W. The discharge port 426 is configured by, for example, an opening having a rectangular shape when seen in a plan view. In this example, the discharge port 426 is formed in a rectangular shape having a long side in the circumferential direction of the transport pipe 440, but is not limited to this shape.

  The concave portion 428 prevents the waste developer from dripping out of the conveyance path, and the peripheral portion of the discharge port 426 on the downstream side in the conveyance direction W of the developer is slightly recessed from the plane portion of the conveyance tube 440. It is formed with. The length in the width direction (long side) orthogonal to the conveyance direction W of the recess 428 is selected to be substantially the same as the length of the discharge port 426 in the width direction orthogonal to the conveyance direction W, for example. The length of the concave portion 428 in the transport direction W is selected such that the concave portion 428 is covered (does not protrude) by the shutter member 430 when the shutter member 430 is in the closed position. Thereby, leakage of the waste developer from the recess 428 can be prevented. Note that the recesses 428 may be formed on both ends of the discharge port 426 in the direction orthogonal to the transport direction W.

  The depth (indentation amount) H of the recess 428 is selected to be at least twice the outer diameter of at least one of the toner and carrier constituting the developer. The toner and carrier do not have two layers unless they are charged. Therefore, by setting the depth H of the concave portion 428 to be at least twice the outer diameter of the toner and the carrier, even when the carrier or the like adheres to the concave portion 428, the carrier or the like does not protrude (does not protrude) from the concave portion 428. can do. Further, even if the toner and the carrier adhere to form two layers, the depth H described above can surely prevent the toner and the carrier from protruding from the recess 428. For example, in the case of a carrier coated with a resin, the outer diameter of the carrier is, for example, 50 μm to 150 μm. Therefore, the depth H of the recess 248 may be selected to be twice that, for example, 100 μm to 300 μm.

  The shutter member 430 is a cylindrical member that is formed along the outer peripheral surface of the transport pipe 440 and is made of a material that is not charged. The outlet 426 is opened and closed by sliding as a guide. The shutter member 430 is cut out at portions corresponding to the discharge port 426 and the recess 428 so that the discharge port 426 and the recess 428 are exposed when the shutter member 430 is moved to a position where the discharge port 426 is closed. In addition, the shutter member 430 is biased by a spring (not shown) on the distal end side of the transport pipe 440, and a position where the discharge port 426 is closed is a normal position.

  The seal member 432 is a member for preventing leakage of the developer, and is integrally formed inside the seal member 432 at the distal end portion of the shutter member 430. Since the seal member 432 overlaps the discharge port 426 and the recess 428 in the movable region of the shutter member 430, the seal member 432 is formed along the peripheral surface other than the discharge port 426 and the recess 428 of the transport pipe 440. As a result, the gap between the inner peripheral surface of the shutter member 430 and the outer peripheral surface of the transport tube 440 is sealed by the seal member 432.

  The seal member 434 is a member for preventing leakage of the developer, and is integrally formed inside the seal member 434 at the rear end portion of the shutter member 430. Since the seal member 434 does not overlap the discharge port 426 and the recess 428 in the movable region of the shutter member 430, the seal member 434 is formed in a ring shape (annular shape) over the entire circumference of the transport pipe 440. As a result, the gap between the inner peripheral surface of the shutter member 430 and the outer peripheral surface of the transport tube 440 is sealed by the seal member 434.

[Configuration Example of Collection Unit 200]
FIG. 6 shows a state where the transport pipe 440 of the developing device 4 is attached to the collection unit 200. The collection unit 200 collects the waste developer discharged from the discharge port 426 of the developing device 4. As shown in FIG. 6, the collection unit 200 includes a collection unit main body 210 formed of an elongated box. The collection unit main body 210 has an insertion port 212 having a shape corresponding to the outer diameter of the transport pipe 440 on the surface into which the developing device 4 is inserted. A ring-shaped seal member 214 is provided on the inner periphery of the insertion port 212. When the conveyance tube 440 of the developing device 4 is inserted into the insertion port 212 of the collection unit 200, the gap between the conveyance tube 440 and the collection unit main body 210 at the periphery of the insertion port 212 is sealed by the seal member 214.

[Operation example when attaching / detaching the developing device 4 to / from the collecting unit 200]
Next, an example of the operation when the developing device 4 is attached to and detached from the collection unit 200 will be described with reference to FIGS. 3 (A), 3 (B), 4 (A), 4 (B), and 6. FIG. To do. When the operation of inserting the developing device 4 into the collecting unit 200 is started, a projection (not shown) provided on the shutter member 430 of the developing device 4 is caught (engaged) with the engaged portion of the collecting unit main body 210. The transport pipe 440 other than the shutter member 430 moves toward the inside of the collection unit main body 210. Accordingly, the shutter member 430 is opened, and the discharge port 426 is opened (see FIG. 3B). The waste developer in the transport pipe 440 is discharged from the discharge port 426 and recovered by the recovery unit 200.

  On the other hand, when the operation of pulling out the developing device 4 from the collection unit 200 is started, the shutter member 430 is moved to the direction of the conveyance tube 440 by the bias of a spring (not shown) as the conveyance tube 440 moves away from the collection unit 200. Return to the initial position (see FIG. 3A). As a result, the shutter member 430 is closed and the discharge port 426 is closed. At this time, since the concave portion 248 is provided in the transport pipe 440, the waste developer attached to the concave portion 248 is not worn out by the closing operation of the shutter member 430.

  As described above, according to the present embodiment, for example, even when the amount of waste developer discharged is large, the waste developer can be attached to the recess 248 provided in the peripheral portion of the discharge port 426. Thereby, in the closing operation of the shutter member 430 when the developing device 4 is pulled out from the collection unit 200, the waste developer is scraped off by the shutter member 430 and falls outside the conveyance path, or the seal member of the collection unit 200 It can be prevented from adhering to 214.

  Further, according to the present embodiment, by providing the recess 428 in the transport pipe 440, it is possible to prevent the waste developer from falling out of the transport path without using a wiping member, a cleaning member, or the like. Thereby, in the image forming apparatus 100, it is possible to achieve low cost and space saving.

  Further, according to the present embodiment, since the discharge port 426 is formed on the lower surface of the transport pipe 440, the developer can be efficiently dropped into the collection unit 200.

  Furthermore, according to the present embodiment, the tip end portion of the shaft 420a of the stirring and conveying member 420 extends to the downstream side in the transport direction W from the discharge port 426, and the tip portion of the shaft 420a is supported by the support portion 424. ing. Further, the rear end portion of the shaft 420a is also supported by a support portion (not shown). Thereby, since the eccentricity at the time of rotation of the stirring conveyance member 420 can be reliably prevented, the accuracy of the developer conveyance position can be maintained.

[Modification Example of Recess 428 (Part 1)]
FIG. 7 shows an example of a modification of the recess 428. Note that detailed descriptions of components having substantially the same functional configuration as those of the above-described embodiment are omitted. As shown in FIG. 7, the stepped portion 428 a that connects the plane of the recess 428 and the plane of the transfer tube 440 is formed by an inclined surface. Thereby, when the shutter member 430 is opened and closed, the stepped portion 428a serves as a guide, and the edge of the shutter member 430 can be prevented from being caught by the stepped portion 428a. As a result, a smooth opening / closing operation of the shutter member 430 can be realized.

[Modification Example of Recess 428 (Part 2)]
FIG. 8 shows an example of a modified example of the recess 428 and shows an example of the configuration of the side surface of the transfer tube 440. Note that detailed descriptions of components having substantially the same functional configuration as those of the above-described embodiment are omitted. As shown in FIG. 8, the concave portion 428 includes a plurality of groove portions (slits) 428 b, and these groove portions 428 b are formed in the peripheral portion of the discharge port 426 on the downstream side in the developer transport direction W. The plurality of groove portions 428b are formed at predetermined intervals along a side perpendicular to the conveyance direction W of the discharge port 426, and one side of the groove portion 428b is formed in parallel with the conveyance direction W. Further, the portion of the transport pipe 440 between the adjacent grooves 428 b and 428 b functions as a guide for the shutter member 430. Thereby, according to this example, it is possible to achieve both the function of preventing the waste developer from falling off by the recess 428 and the guide function during the opening / closing operation of the shutter member 430.

[Modification of Stirring Conveying Member 420]
FIG. 9 shows an example of a modified example of the stirring and conveying member 420. Detailed descriptions of components having substantially the same functional configuration as those of the above-described embodiment are omitted. As shown in FIG. 9, the stirring and conveying member 420 includes a shaft 420a and a blade 420b formed in a spiral shape on the shaft 420a. In this example, the blade 420b is formed up to the upper position where the discharge port 426 is formed, that is, the most downstream portion 422a in the developer transport direction W. Thus, the developer conveying force can be improved while preventing the waste developer attached to the periphery of the discharge port 426 from dropping out of the conveying path by the recess 428.

  It should be noted that the technical scope of the present invention is not limited to the above-described embodiments, and includes those in which various modifications are made to the above-described embodiments without departing from the spirit of the present invention. For example, in the above-described embodiment, the developing device 4 is configured to be attached to and detached from the collection unit 200, but the present invention is not limited to this. For example, the collection unit 200 may be configured to be attached to and detached from the developing device 4.

4 Developing Device 400 Developing Device Main Body 402 Partition 420 Stirring conveying member (conveying member)
422 Developer supply path 424 Support portion 426 Discharge port 428 Recess 430 Shutter member 432 Seal member 434 Seal member 440 Conveying tube 450 Developing roller

Claims (10)

A developing device that can be attached to a collecting unit for collecting a developer,
A developing device main body containing the developer and having a discharge port for discharging the developer on the downstream side in the transport direction of the developer;
A conveying member provided in the developing device main body, for conveying the developer by a rotating operation;
A shutter member that is provided on a peripheral surface of the developing device main body and opens and closes the discharge port according to an attaching / detaching operation with respect to the recovery unit
The developing device main body has a concave portion in which the developing device main body is recessed at least in the peripheral portion of the discharge port on the downstream side in the transport direction of the developer. The developing device according to claim 1, wherein a step portion between the concave portion and the developing device main body is formed by an inclined surface. The developing device according to claim 1, wherein the discharge port is formed on a lower surface of the developing device main body. A seal member provided inside the shutter member;
The developing device according to any one of claims 1 to 3, wherein the seal member is provided at a position that does not overlap the discharge port and the concave portion of the developing device main body. The developing device according to claim 4, wherein the seal member is provided over the entire circumference of the developing device main body. The developing device according to claim 1, wherein a depth of the concave portion of the developing device main body is twice or more an outer diameter of a toner or a carrier constituting the developer. . The developing device according to any one of claims 1 to 6, wherein the developing device main body and the shutter member are materials that are not charged. The developing device according to claim 1, wherein the concave portion includes a plurality of groove portions. The transport member has a shaft extending along the developer transport direction, and a blade formed in a spiral shape on the shaft,
The shaft extends downstream from the discharge port in the transport direction of the developer, and a tip portion of the shaft is rotatably supported by a support portion constituting the developing device main body.
The developing device according to claim 1, wherein the blade extends to a position where the discharge port is formed.   An image forming apparatus comprising the developing device according to claim 1.

Images