JP2012098319A - Developer transport device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simply configured, economically produced developer transport device and an image forming apparatus having the device.SOLUTION: A developer transport device for transporting a developer includes: a reservoir member for reserving the developer; and a transport member accommodated by the reservoir member and having a spiral blade part for transporting the developer by rotating, the developer reserved in the reservoir member. Further, the reservoir member is disposed so that the height from the bottom surface of the image forming apparatus internally having the reservoir member is higher toward downstream, in a transport direction, of the developer transported by the transport member than toward upstream; and the blade part has a first zone and a second zone positioned upstream of the first zone in the transport direction, with at least the blade part in the first zone having at least one cutoff portion for each pitch of the blade part.

Description

  The present invention relates to a developer conveying device that conveys a developer, and an image forming apparatus having the developer conveying device.

  2. Description of the Related Art Conventionally, in a developer conveying apparatus that conveys a developer from a developer container containing a developer to a developing apparatus that visualizes a latent image, two developer conveying members having screw blades are provided, and both developers By conveying the developer in the reverse direction, one that conveys the developer while circulating it, or one that conveys the developer in one direction by providing one developer conveying member having a screw blade ( (See Patent Document 1).

JP 2003-66706 A

  However, the developer conveying device described in Patent Document 1 cannot circulate the developer with one conveying member, and requires two conveying members to circulate the developer, resulting in a complicated structure. In addition, there is a problem that the manufacturing cost of the apparatus increases due to the complicated structure.

  SUMMARY An advantage of some aspects of the invention is that it provides a developer transport device having a simple structure and low manufacturing cost, and an image forming apparatus having the developer transport device.

  The above object is achieved by the following configuration.

1. A developer conveying device for conveying a developer,
A storage member for storing the developer;
A conveyance member having a spiral blade portion that conveys the developer stored in the storage member by being stored in the storage member and rotating;
The storage member has a height on the downstream side relative to a height on the upstream side in the transport direction of the developer transported by the transport member with respect to the height from the bottom surface of the image forming apparatus main body having the storage member inside. Arranged to be high,
The blade portion has a second region located upstream of the first region with respect to the first region and the transport direction,
At least the blade portion of the first region has at least one missing portion for each pitch of the blade portion.

  2. 2. The developer conveying device according to 1 above, wherein the missing portion is a notch or a hole.

  3. 3. The developer conveying apparatus according to claim 1, wherein the size of the missing portion increases gradually or stepwise from an upstream side to a downstream side in the conveying direction.

  4). 4. The developer conveying device according to claim 1, wherein an interval between the missing portions in the conveying direction is equal to a pitch of the blade portions.

  5. 5. The developer conveying device according to any one of claims 1 to 4, wherein the blade portion in the second region has at least one missing portion for each pitch of the blade portion.

  6). The linear distance from the rotation center of the conveying member to the outer periphery of the blade portion gradually or stepwise decreases from the upstream side to the downstream side in the conveying direction. 2. The developer conveying device according to item 1.

  7). 7. The developer conveying device according to any one of 1 to 6, wherein the storage member includes a plurality of the conveying members.

8). A developer conveying device for conveying a developer,
A storage member for storing the developer;
A conveyance member having a spiral blade portion that conveys the developer stored in the storage member by being stored in the storage member and rotating;
The storage member has a height on the downstream side relative to a height on the upstream side in the transport direction of the developer transported by the transport member with respect to the height from the bottom surface of the image forming apparatus main body having the storage member inside. Arranged to be high,
The blade portion has a second region located upstream of the first region with respect to the first region and the transport direction,
At least in the blade portion of the first region, the linear distance from the rotation center of the transport member to the outer periphery of the blade portion is gradually or stepwise decreased from the upstream side to the downstream side in the transport direction. A developer transport device, wherein the developer transport device is formed.

  9. The blade portions of the first region and the second region are gradually or stepwise as the linear distance from the rotation center of the transport member to the outer periphery of the blade portion moves from the upstream side to the downstream side in the transport direction. 9. The developer conveying device as described in 8 above, wherein the developer conveying device is formed to be small.

  10. The developer transport device according to 8 or 9, wherein the storage member includes a plurality of the transport members.

11. A replenishing unit that replenishes the developing unit with developer conveyed by the conveying member;
The replenishment section stores the developer sent from the transport member;
11. The developer conveying device according to any one of 1 to 10 above.

12 A developer container for storing the developer, the developer transport device according to any one of 1 to 11 above, and a developing unit that performs development using the developer replenished from the developer transport device;
An image forming apparatus.

  According to the above invention, it is possible to provide a developer transport device having a simple structure and low manufacturing cost, and an image forming apparatus having the developer transport device.

FIG. 2 is an explanatory diagram of an image forming apparatus. FIG. 2 is an explanatory view (side view) of the developing device. Explanatory drawing (side view) of an intermediate conveyance apparatus. Explanatory drawing (sectional drawing) which looked at the developer conveying apparatus from the side. It is explanatory drawing of the 2nd form of a conveyance member. FIG. 5 is a cross-sectional view of the developer conveying device shown in FIG. 4 as viewed from a first region side of a conveying member. Explanatory drawing (side view) of the image development part 5. FIG. Explanatory drawing (sectional drawing) which looked at the 2nd form of the developer conveying apparatus from the side surface.

  The wording will be described before the description of each component.

  Regarding the developer transport device, the upstream refers to the side on which the developer is transported, and the downstream refers to the side on which the developer is transported.

  FIG. 1 is an explanatory diagram of an image forming apparatus.

  As an example of the image forming apparatus, an image forming apparatus referred to as a tandem type full color copying machine will be described below as an example.

  The automatic document feeder B placed on the upper side of the main body of the image forming apparatus A picks up the documents S stacked on the paper feed tray B1 one by one and conveys them to the document reading area r. The document S in which the image information is read is discharged to the discharge tray B2.

  Hereinafter, the configuration of the main body of the image forming apparatus A excluding the automatic document feeder B will be described.

  The document image reading unit 1 includes a light source 11, a movable scanning unit 12, and an optical system 14 that forms an image of the document image on a line image sensor 13.

  For example, in the case of a stationary optical system type reading operation, the scanning unit 12 is fixed to the document reading area r, and the image of the document S conveyed by the automatic document feeder B is read. In the case of the moving optical system type reading operation, the image of the document S placed on the document image reading unit 1 is read while moving the scanning unit 12.

  The analog signal of the original image photoelectrically converted by the line image sensor 13 is subjected to analog processing, A / D conversion, shading correction, image compression processing, etc., and Y (yellow), M (magenta), C (cyan), This is digital image data for each color of K (black).

  On the drum-shaped photosensitive member 21 (21Y, 21M, 21C, 21K) as the first image carrier, an exposure unit 22 (22Y, 22M, 22C, 22K) that forms a latent image based on digital image data of each color. A developing device 2 (2Y, 2M, 2C, 2K) for developing a latent image corresponding to each color with toner, and a charging unit 24 (24Y, 24M, 24C, 24K) for uniformly charging the photosensitive member 21; A cleaning unit 25 (25Y, 25M, 25C, 25K) for removing toner remaining on the surface of the photosensitive member 21 without being transferred to the intermediate transfer member 26 is disposed.

  FIG. 1 shows a case where the developing device 2 includes a developing unit 5, a developer transport device 6, a developer container holding member 71, and an intermediate transport device 8.

  Further, a semiconductive endless belt-like intermediate transfer member 26 that is rotatably supported by rollers 261, 262, 263, and 264 is disposed facing the photosensitive member 21 (21 Y, 21 M, 21 C, and 21 K). The intermediate transfer member 26 is driven in the direction of arrow a through a roller 263 by a driving device (not shown).

  The toner images of the respective colors carried on the respective photoconductors 21 are sequentially transferred to the intermediate transfer body 26 by pressing of the primary transfer rollers 27 (27Y, 27M, 27C, 27K), and a combined color image is formed. .

  The toner remaining on the intermediate transfer member 26 without being transferred to the recording material is removed by the cleaning unit 28.

  The paper feed unit 3 includes a plurality of paper feed cassettes 31 that are paper storage members, and a recording material P is accommodated inside the paper feed cassette 31.

  Examples of the recording material P include resin sheets and sheet-like paper. Hereinafter, the recording material is referred to as paper P.

  The accommodated paper P is picked up one by one by a paper feed roller 32, conveyed to a transfer area 35 through a plurality of conveyance rollers 33 and a registration roller 34, and intermediate to the paper P conveyed by the pressure of the secondary transfer roller 36. The synthesized toner images on the transfer body are transferred collectively.

  The sheet P on which the toner image has been transferred is separated from the intermediate transfer body 26 by curvature, and the toner image is fixed to the sheet P by the heating and pressing of the heating unit 41 and the pressure unit 42 of the fixing device 4.

  The paper P on which the toner image is fixed is sandwiched between the paper discharge rollers 37 and discharged from the discharge port 38 to the outside of the apparatus.

  The main body of the image forming apparatus A has an operation panel SP that displays various types of information and allows the user to input various types of information according to the display contents.

  The above-described operation is controlled by the control unit C that controls the entire image forming apparatus.

  The tandem full-color copying machine has been described above as an example. Needless to say, the developing unit 2 can be applied to a monochrome copying machine.

  FIG. 2 is an explanatory view (side view) of the developing device.

  The developing device 2 includes at least a developing unit 5 and a developer conveying device 6. Hereinafter, the developing device 2 includes the developer conveying device 6 and the developer in addition to the developing unit 5 and the developer conveying device 6. In the following description, it is assumed that an intermediate conveyance device 8 that conveys the developer G introduced from the developer container 7 to the developer conveyance device 6 is provided between the developer container 7 that stores G.

  In this case, the developer discharge port of the developer container 7 faces the charging port 81 of the intermediate conveyance device 8, and the developer discharge port of the intermediate conveyance device 8 faces the charging port 65 of the developer conveyance device 6. The developer container 7, the developer transport device 6, and the developing unit 5 are arranged so that the developer discharge port of the developer transport device 6 faces the developer charging port of the developing unit 5.

  The developer container 7 is detachably held by a developer container holding member 71 fixed to the casing of the image forming apparatus A (not shown), and is used when the developer G is no longer in the developer container 7. Can be exchanged by a person.

  In the developer container holding member 71, the developer container 7 is rotated by the control unit C, and the developer G stored in the developer container 7 is discharged toward the input port 81 of the intermediate conveyance device 8.

  In the intermediate conveyance device 8, the spiral screw member 82 mounted inside is rotated by the control unit C, conveys the developer G in the direction of arrow b, and falls toward the inlet 65 of the developer conveyance device 6. Let

  The developer transport device 6 transports a developer G introduced by a control member C, which will be described later, and a replenishment unit 9 and the like, and the transported developer G is stored in the developer transport device 6. It falls from the discharge port 66 toward the input port 57 of the developing unit 5.

  In the developing unit 5, the screw 51 mounted inside is rotated by the control unit C, the developer G is agitated, and the developer G charged by the agitation is attached to the developing roller 55 via the paddle 56, and is attached to the photoreceptor 21. The formed latent image is visualized.

  FIG. 3 is an explanatory diagram (side view) of the intermediate transfer device.

  The intermediate conveyance device 8 includes a screw member 82 that is a conveyance member that conveys the developer G, and a cylindrical developer conveyance member that rotatably supports the screw member 82 and serves as a conveyance path for the developer G. 83.

  The developer G introduced into the introduction port 81 from the developer container 7 is conveyed in the direction of the arrow b by the rotation of the screw member 82 and falls from the discharge port 84 toward the introduction port 65 of the developer conveyance device 6.

  The screw member 82 is driven to rotate by a drive unit (not shown) that rotates the screw member 82, and the control unit C (not shown) supplies the developer G from the developer container 7 and the developer. While the shortage information of the developer G is output from the conveying device 6, the drive unit (not shown) is driven to rotate the screw member 82.

  FIG. 4 is an explanatory view (cross-sectional view) of the developer transport device 6 as viewed from the side.

  The developer transport device 6 transports the developer G stored in the developer container 7 toward the developing unit 5. The developer transport device 6 stores at least the developer G and stores the developer G stored in the storage member 62. And a conveying member 63 that conveys the agent G.

  In this case, the developer transported by the transport member 63 is directly fed from the discharge port 66 of the developer transport device 6 (storage member 62) to the input port 57 of the developing unit 5.

  Hereinafter, the developer transport device 6 includes a storage member 62, a transport member 63, and a replenishment unit 9 that stores the developer G transported by the transport member 63 and replenishes the developing unit 5. The case where the developer transported in step 1 is temporarily stored in the replenishing unit 9 and then charged into the charging port 57 of the developing unit 5 from the discharge port 66 of the developer transporting device 6 through the replenishing unit 9 will be described.

  A first developer conveying device 6a, which is a first form of the developer conveying device 6, will be described with reference to FIG.

  Note that the first developer conveying device 6a is also referred to as the developer conveying device 6 when it is not necessary to specify the developer conveying device as the first form and the other forms.

  The developer transport device 6 of the present invention transports the developer G stored in a developer container 7 (not shown) toward the developing unit 5.

  The developer transport device 6 stores the developer G sent from the developer container 7 (not shown) via the intermediate transport device 8, and is stored in the storage member 62 and stored by rotating. Transported by a transport member 63 having a spiral blade 631 that transports the developer G stored in the member 62, a replenishment unit sensor 64 that detects the developer G stored in the storage member 62, and the transport member 63. A replenishment unit 9 that temporarily stores the developed developer G and sequentially replenishes the stored developer G to the developing unit 5.

  The storage member 62 has a height higher than the height h1 on the upstream side in the conveyance direction (arrow c direction) of the developer G conveyed by the conveyance member 63 with respect to the height from the bottom surface L of the main body of the image forming apparatus A. The h2 is arranged to be higher.

  Note that the developer conveying device 6 is suitable when the inclination θ of the storage member 62 due to the difference in height is equal to or greater than the angle at which the developer G in the storage member 62 naturally slides downward due to the earth's attractive force. Available to: That is, the inclination θ is equal to or greater than the angle at which the developer G in the storage member 62 naturally slides downward due to the earth's attractive force.

  In addition, in the case where an oscillating portion (not shown) that applies vibration to the storage member 62 is provided, the inclination θ is equal to or greater than the angle at which the developer G in the storage member 62 slides downward due to vibration and the earth's attractive force. .

  The storage member 62 has a circular cross-sectional shape when the developer conveying device 6 is viewed from the left side of the drawing. The lower half may be a semi-cylindrical shape, and the upper half may be U-shaped with the end of the lower cylinder extending straight upward.

  The blade portion 631 has a first region 637 and a second region 638 located upstream of the first region 637 with respect to the developer G transport direction (arrow c direction).

  The transport member 63 is rotatably supported by the storage member 62 at both ends of the shaft 632 with bearings 633 so that the shaft 632 of the transport member 63 and the lower inner wall 621 of the storage member 62 are parallel to each other.

  Further, a part of the developer G introduced from the introduction port 65 passes through a later-described missing portion 6313 (broken line portion) by its own weight and moves toward the upstream side, and the remaining developer is moved downstream by the conveying member 63. Be transported.

  Then, in order to ensure that the developer G positioned in the second region 638 that has fallen through the free fall and the missing portion 6313 (broken line portion), which will be described later, has fallen toward the upstream side is reliably conveyed toward the downstream side. The conveying member 63 is supported by the storage member 62 so that the gap between the outer periphery 6316 of the blade portion 631 located in the second region 638 and the lower inner wall 621 of the storage member 62 is not in contact with each other. .

  Then, the motor 636 rotates through a gear 634 attached to the shaft 632, a belt 635, and the like.

  The replenishing section 9 includes a screw member 91 having a helical screw blade and a cylindrical member 92 that houses the screw member 91. The screw member 91 is rotationally driven by a drive means (not shown), and stored. The developer G charged from the member 62 is transported and discharged to the charging port 57 of the developing unit 5.

  The control unit C (not shown) rotates the motor 636 when the developer G is being supplied from the intermediate conveyance device 8 to the developer conveyance device 6 and according to information that the developer G in the development unit 5 is insufficient. The developer G stored in the storage member 62 is conveyed in the direction of arrow c.

  Further, the screw member 91 is rotationally driven by driving means (not shown) according to the information that the developer G in the developing unit 5 is insufficient, and the developer G is conveyed and loaded into the developing unit 5.

  Note that the conveying member 63 of the first developer conveying device 6a, which is the first form shown in FIG. 4, has a missing portion 6313 (broken line portion) in the blade portion 631.

  The output of the developer sensor 64 that detects the developer G is input to a control unit C (not shown). When the output of the developer sensor 64 is OFF, that is, when the developer G is insufficient, the control unit C controls the intermediate conveyance device 8. The developer G is supplied to the developer conveying device 6 and the output of the developer sensor 64 is turned on, that is, the operation of the intermediate conveying device 8 is stopped according to the information on the satisfaction of the developer G, and the development to the developer conveying device 6 is performed. Stop charging the agent.

  Hereinafter, the 1st conveyance member 63a which is the 1st form of the conveyance member 63 is demonstrated.

  In the first conveying member 63a, the first region blade portion 6311 that is at least the blade portion 631 located in the first region 637 has at least one missing portion 6313 (broken line portion) for each pitch p1 of the blade portion 631. Yes.

  The size of the missing portion 6313 increases gradually or stepwise from the upstream side to the downstream side in the developer G conveyance direction (arrow c direction).

  The interval in the conveyance direction (arrow c direction) of the developer G at the missing portion 6313 is equal to the pitch p1 of the blade portions 631.

  In addition, the missing portion 6313 is not provided in the second region blade portion 6312 which is the blade portion 631 located in the second region 638.

  The pitch p1 is equal between the first region 637 and the second region 638.

  Note that at least one missing portion may be provided for each pitch p1 in the blade portion 631 located in the second region 638 as well. In this case, the size of the missing portion 6313 provided in the blade portion 631 of the second region 638 is made smaller than the size of the missing portion 6313 provided in the blade portion 631 of the first region 637.

  By providing the blade portion 631 located in the second region 638 with a missing portion smaller than the size of the missing portion 6313 provided in the blade portion 631 of the first region 637, the circulation of the developer G inside the storage member 62 is at the upper end. To the bottom.

  With the configuration described above, the developer G introduced into the developer transport device 6 from the developer container 7 (not shown) via the intermediate transport device 8 is circulated through the storage member 62 by the rotation of the transport member 63, and the arrow c It is transported in the direction.

  As described above, the developer conveying device 6 is installed so that the height on the downstream side is higher than the upstream side, and the missing portion 6313 is provided in the first region blade portion 6311. A part of the developer G transported passes through the missing portion 6313 by the earth's attractive force and falls toward the second region 638.

  At this time, since the size of the missing portion 6313 of the first region blade portion 6311 increases gradually or stepwise from the upstream side toward the downstream side, the developer G falling through the missing portion 6313 falls. The amount is larger on the downstream side than on the upstream side, and as a result, the transport amount of developer G per unit time is smaller on the downstream side than on the upstream side.

  Then, the falling developer G is transported again toward the first region 637 by the rotation of the transport member 63 while being mixed with the newly introduced developer G.

  The conveyance member 63 may be provided with a coil (not shown) in which the shaft 632 side is hollow instead of the blade portion 631 formed in the first region 637. In this case, the diameter of the coil is narrower on the downstream side than on the upstream side.

  As described above, the case where the number of the developer conveying devices 6 is one and one conveying member 63 is installed inside the storage member 62 has been described. However, a plurality of developer conveying devices 6 may be provided. Further, a plurality of conveying members 63 may be provided inside the storage member 62 of one developer conveying device 6.

  When a plurality of conveying members 63, for example, two conveying members 63 are provided, the two conveying members 63 are mounted in parallel to the inside of the storage member 62, rotate in the same direction and in the same direction, and develop. Each agent G is conveyed from the upstream side toward the downstream side.

  Providing a plurality of developer conveying devices 6 or a plurality of conveying members 63 increases the conveying amount of the developer G, and the developing unit 5 requires a large amount of the developer G as in a high-capacity image forming apparatus. Even in this case, the shortage of the developer can be prevented, and the decrease in the image density due to the shortage of the developer can be prevented.

  FIG. 5 is an explanatory diagram of a second form of the conveying member.

  The transport member 63b of the second form has a missing portion 6313 (broken line portion) in the first region blade portion 6311, and the linear distance d1 from the rotation center 639 of the transport member 63b to the outer periphery 6316 of the blade portion 631 is the first. In one region 637, the area decreases gradually or stepwise from the upstream side to the downstream side in the developer G conveyance direction (arrow c direction).

  When the missing portion 6313 is a notch 6314 described later, the linear distance d2 from the rotation center 639 of the conveying member 63 to the notched end 6317 is shorter than the linear distance d1.

  By decreasing the linear distance d1 gradually or stepwise from the upstream side to the downstream side in the conveyance direction (arrow c direction) of the developer G, the developer G has the missing portion 6313, the storage member 62, and the blades. The amount of the developer G that can pass through between the outer periphery 6316 of the part 631 and fall through the part 631 is larger than that of the first conveying member 63a described above.

  Thus, the developer G is not stored or compressed in the vicinity of the discharge port 66 provided in the most downstream portion of the storage member 62 for a long time, and the developer G is fixed in the vicinity of the discharge port 66. The developing unit 5 can be replenished stably without clogging or clogging.

  6 is a cross-sectional view of the developer transport device 6 shown in FIG. 4 as viewed from the first region side of the transport member.

  A transport member 63 is mounted inside the storage member 62, and a spiral blade portion 631 is formed on the shaft 632 of the transport member 63.

  The first region blade portion 6311 (the front side in the drawing) has a missing portion 6313, but the second region blade portion 6312 located behind the first region blade portion 6311 (the back side in the drawing) has no missing portion 6313. .

  FIG. 6A shows a case where the missing portion 6313 of the first region blade portion 6311 (front side in the drawing) is a notch 6314, and FIG. 6B shows the missing portion of the first region blade portion 6311 (front side in the drawing). Reference numeral 6313 denotes the case of the hole 6315.

  In FIG. 6A, the notch 6314 of the first region blade portion 6311 increases gradually or stepwise from the upstream side (the back side in the figure) toward the downstream side (the near side in the figure).

  The notch 6314 only has to pass through the notch 6314 toward the upstream side (the back side in the figure), and the shaft 632 side has an arc shape as shown in the figure. It may be.

  In FIG. 6B, the hole 6315 of the first region blade portion 6311 increases gradually or stepwise from the upstream side (the back side in the figure) toward the downstream side (the near side in the figure).

  The hole 6315 only needs to pass through the hole 6315 toward the upstream side (the back side in the figure), and may be semicircular, circular, elliptical, or polygonal as illustrated. .

  As described above with reference to the drawings, in the developer transport device 6 whose height on the downstream side is higher than that on the upstream side, the spiral blade portion in which the missing portion 6313 is provided inside one storage member 62. By rotating one conveying member 63 having 631, it becomes possible to convey the developer G to the developing unit 5 and circulate inside the developer conveying device 6 with only one conveying member 63. The structure of the agent transport device can be simplified.

  FIG. 7 is an explanatory diagram (side view) of the developing unit 5.

  The developing unit 5 includes a developer container 52 that temporarily stores the developer G, a first screw 53 that is a screw 51 that conveys the developer G in the developer container 52 while stirring, and a second screw 53. A screw 54; a developing roller 55 arranged to rotate opposite to the photosensitive drum 21; and a paddle 56 for sending the developer G conveyed through the second screw 54 toward the developing roller 55. Yes.

  Then, the developer G charged into the charging port 57 from the developer conveying device 6 is stirred and conveyed by the rotation of the first screw 53 and the second screw 54, and the developer G to which electric charge is applied by frictional charging. Is sent out to the developing roller 55 by the paddle 56 for development.

  The control unit C (not shown) rotates the first screw 53 and the second screw 54 at least while the developer G is being fed from the developer transport device 6.

  FIG. 8 is an explanatory view (cross-sectional view) of the second embodiment of the developer conveying device as viewed from the side.

  Hereinafter, a second developer transport device 6b, which is a second form of the developer transport device 6, will be described with reference to FIG.

  The second developer conveying device 6b is the same as the first developer conveying device 6a except that the storage member and the conveying member are different from the first developer conveying device 6a described above. The member 63 ′ will be described.

  The storage member 62 ′ has a height h2 on the downstream side higher than a height h1 on the upstream side in the transport direction (arrow c direction) of the developer G with respect to the height from the bottom surface L of the main body of the image forming apparatus A. The cross-sectional shape of the storage member 62 ′ when the second developer transport device 6b is viewed from the left side of the drawing is circular (the cross-sectional area of the storage member 62 ′ in the first region 637 and the second It is equal to the cross-sectional area of the storage member 62 ′ in the region 638).

  In addition, S1 indicates a cross-sectional area (illustration ellipse) of the storage member 62 'on a surface orthogonal to the transport direction of the developer G.

  S2 indicates the projected sectional area (illustration ellipse) of the second region blade portion 6312 ′, and S3 is the closest to the second region 638 among the first region blade portions 6311 ′ provided in the first region 637. A projected cross-sectional area (illustration ellipse) of the blade portion 631 ′ is shown, and S4 is a blade portion 631 provided at a position farthest from the second region 638 in the first region blade portion 6311 ′ provided in the first region 637. 'Shows the projected cross section (ellipse shown).

  The spiral blade portion 631 ′ formed on the conveying member 63 ′ does not have the aforementioned missing portion.

  In the first region 637, the linear distance d ′ from the rotation center 639 ′ of the transport member 63 ′ to the outer periphery 6316 ′ of the first region blade 6311 ′ is upstream of the transport direction (arrow c direction) of the developer G. It is formed so as to decrease gradually or stepwise from the side toward the downstream side.

  The linear distance d ′ from the rotation center 639 ′ of the conveying member 63 ′ to the outer periphery 6316 ′ of the first region blade portion 6311 ′ in the first region 637 and the second region 638, not only in the first region 637, You may form so that it may become small gradually or in steps as it goes to the downstream from the upstream of the conveyance direction (arrow c direction) of the developer G.

By these, even when the inner diameter D1 of the storage member 62 ′ and the outer shape D2 of the second region blade portion 6312 ′ change very little, even if the difference is very small,
The outer shape D3 of the blade portion 631 ′ closest to the second region 638 among the blade portions 631 ′ of the first region 637 is smaller than the outer shape D2 of the second region blade portion 6312 ′.
In the first region 637, the outer shape of the blade portion 631 ′ located on the downstream side of the blade portion 631 ′ closest to the second region 638 decreases in order, and the blade portion provided at the position farthest from the second region 638. The outer shape D4 of 631 ′ is the smallest.

  In other words, the cross-sectional area S1 of the storage member 62 ′, the projected cross-sectional area S2 of the second region blade portion 6312 ′, the projected cross-sectional area S3 of the first region blade portion 6311 ′ closest to the second region 638, and the second Each blade portion is formed such that the projected cross-sectional area S4 of the first region blade portion 6311 ′ provided at a position farthest from the region 638 has the following relationship.

The area obtained by subtracting the projected sectional area S4 from the sectional area S1 is larger than the area obtained by subtracting the projected sectional area S3 from the sectional area S1,
The area obtained by subtracting the projected sectional area S3 from the sectional area S1 is larger than the area obtained by subtracting the projected sectional area S2 from the sectional area S1.

(Cross-sectional area S1-projected cross-sectional area S4)> (cross-sectional area S1-projected cross-sectional area S3)> (cross-sectional area S1-projected cross-sectional area S2)
Then, in the first region 637, the projection of the blade portion 631 located downstream from the arbitrary position from the cross-sectional area S1 from the area obtained by subtracting the projected cross-sectional area of the blade portion 631 located at an arbitrary position from the cross-sectional area S1. The area obtained by subtracting the cross-sectional area is wider.

  With the above relationship, the amount of developer G that slips through between the inner wall of the storage member 62 ′ installed so that the height on the downstream side is higher than the upstream side and the outer periphery 6316 ′ of the blade portion 631 ′ is More downstream than upstream.

  Therefore, since the developer G can be circulated, the developer G is not stored or compressed in the vicinity of the discharge port 66 provided in the most downstream portion of the storage member 62, and the developer G is developed. The agent G can be stably replenished to the developing unit 5 without being stuck or clogged in the vicinity of the discharge port 66.

  Further, even when the developer G cannot be supplied to the developing unit 5, the developer G can be stored while being circulated inside the storage member 62, and the deterioration of the fixing due to the stagnation of the developer G can be prevented. .

DESCRIPTION OF SYMBOLS 2 Developing apparatus 5 Developing part 6 Developer conveying apparatus 7 Developer container 9 Replenishing part 62 Storage member 63 Conveying member 631 Blade part 637 1st area | region 638 2nd area | region 639 Rotation center 6313 Missing part 6311 1st area | region blade part 6312 2nd Area blade part 6314 Notch 6315 Hole 6316 Outer periphery A Image forming apparatus C Control part G Developer p1 Pitch

Claims (12)

A developer conveying device for conveying a developer,
A storage member for storing the developer;
A conveyance member having a spiral blade portion that conveys the developer stored in the storage member by being stored in the storage member and rotating;
The storage member has a height on the downstream side relative to a height on the upstream side in the transport direction of the developer transported by the transport member with respect to the height from the bottom surface of the image forming apparatus main body having the storage member inside. Arranged to be high,
The blade portion has a second region located upstream of the first region with respect to the first region and the transport direction,
At least the blade portion of the first region has at least one missing portion for each pitch of the blade portion;
A developer conveying device characterized by the above.   The developer conveying apparatus according to claim 1, wherein the missing portion is a notch or a hole.   3. The developer conveying device according to claim 1, wherein the size of the missing portion increases gradually or stepwise from an upstream side to a downstream side in the conveying direction.   4. The developer conveying device according to claim 1, wherein an interval between the missing portions in the conveying direction is equal to a pitch of the blade portions. 5.   5. The developer conveying device according to claim 1, wherein the blade portion of the second region has at least one missing portion for each pitch of the blade portion.   6. The linear distance from the rotation center of the conveying member to the outer periphery of the blade portion gradually or stepwise decreases from the upstream side to the downstream side in the conveying direction. The developer conveying device according to claim 1.   The developer conveying device according to claim 1, wherein the developer conveying device includes a plurality of the conveying members inside the storage member. A developer conveying device for conveying a developer,
A storage member for storing the developer;
A conveyance member having a spiral blade portion that conveys the developer stored in the storage member by being stored in the storage member and rotating;
The storage member has a height on the downstream side relative to a height on the upstream side in the transport direction of the developer transported by the transport member with respect to the height from the bottom surface of the image forming apparatus main body having the storage member inside. Arranged to be high,
The blade portion has a second region located upstream of the first region with respect to the first region and the transport direction,
At least in the blade portion of the first region, the linear distance from the rotation center of the transport member to the outer periphery of the blade portion is gradually or stepwise decreased from the upstream side to the downstream side in the transport direction. Being formed,
A developer conveying device characterized by the above.   The blade portions of the first region and the second region are gradually or stepwise as the linear distance from the rotation center of the transport member to the outer periphery of the blade portion moves from the upstream side to the downstream side in the transport direction. The developer transport device according to claim 8, wherein the developer transport device is formed to be smaller.   The developer transport device according to claim 8, wherein the storage member includes a plurality of the transport members. A replenishing unit that replenishes the developing unit with developer conveyed by the conveying member;
The replenishment section stores the developer sent from the transport member;
The developer conveying device according to claim 1, wherein A developer container for storing a developer, the developer conveying device according to any one of claims 1 to 11, and a developing unit for developing using the developer replenished from the developer conveying device. ,
An image forming apparatus.

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