JP6691316B2 - Conveying member, developing device, and image forming apparatus - Google Patents

Description

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

  In Patent Document 1, the object is conveyed in the direction of the rotation axis by the rotation of the rotation axis, which is formed in a spiral shape around the rotation axis, and overlaps with each other in a cross section in a direction orthogonal to the rotation axis. A plurality of spiral blades having a point and each of the spiral blades are divided into an upstream spiral blade and a downstream spiral blade, and the upstream spiral blade and the downstream spiral blade are rotated. Passage of a conveyed object that flows in the conveying direction by passing between a plurality of discontinuous portions arranged so that the phases around the axis are different and the upstream spiral blade and the downstream spiral blade that have been divided A conveying member including a regulating portion that regulates the amount is disclosed.

  In Patent Document 2, a plurality of spiral blades that are formed to extend spirally around a rotation axis and have overlapping portions in a cross section in a direction orthogonal to the rotation axis, and the respective spiral blades are provided. The spiral blade includes a discontinuous portion that is divided into a first spiral blade and a second spiral blade that face each other so as to be discontinuous in the extending direction, and in the discontinuous portion, the first spiral blade is provided. The spiral blade and the second spiral blade are arranged so that the phases around the rotation axis are different, and the spiral blade extends on at least one surface of the spiral blade adjacent in the circumferential direction of the rotation axis. A developer stirring / conveying member having an inclined portion whose inclination changes with respect to the existing direction is disclosed.

  Patent Document 3 discloses a multi-row spiral blade having a plurality of spiral blades spirally wound around a common rotation axis, and the multi-row spiral blade so that the multi-row spiral blade is discontinuous in the axial direction. A discontinuous portion that divides the spiral blade, and in the discontinuous portion, the upstream end and the downstream end of the multi-start spiral blade are arranged and formed so as to have different phases around the rotation axis. A developer stirring and transporting member is disclosed.

JP, 2014-160162, A JP, 2014-134619, A JP, 2010-256429, A

  An object of the present invention is to provide a conveying member, a developing device, and an image forming apparatus that can improve the stirring performance of a developer.

According to a first aspect of the present invention, there is provided a first spiral blade, which is provided in a developing device, is formed in a spiral shape around a rotation axis, and conveys a developer in a rotation axis direction by rotation of the rotation axis; A second spiral blade that is spirally formed around the rotation axis in a phase different from that of the first spiral blade and that conveys the developer in the rotation axis direction by the rotation of the rotation axis ; the first spiral blade, and the first spiral blade. The second spiral blade includes a discontinuous portion that divides each of the first spiral blade and the second spiral blade so that the second spiral blade is discontinuous in the axial direction . The developer having a smaller diameter than the first spiral blade overlapping the first spiral blade on a cross section in a direction orthogonal to the rotation axis and remaining in the discontinuous portion is during one rotation Ri by the rotation of the rotary shaft, it is conveyed by the second helical blade Next a developer, divided into a developer remaining in the discontinuity without being conveyed, the developer has remained the discontinuity without being conveyed, by the second spiral blade by rotation of said rotary shaft It is a conveying member that is mixed and conveyed with the developer that is conveyed to.

  The present invention according to claim 2 is arranged such that the end portion of the spiral blade on the upstream side sandwiches the discontinuous portion and the end portion of the spiral blade on the downstream side has a phase difference of 90 ° around the rotation axis. The transport member according to claim 1.

In the present invention according to claim 3, the upstream spiral blade and the downstream spiral blade, which are close to each other in the axial direction of the rotating shaft with the discontinuous portion interposed therebetween, have the same diameter. It is a transport member.

According to a fourth aspect of the present invention, the first spiral blade and the second spiral blade are arranged so that their phases are different from each other by 180 ° in a cross section in a direction orthogonal to the rotation axis. The transport member according to any one of claims 1 to 3.

According to a fifth aspect of the present invention, a developer holding body that holds a developer and a developer that is conveyed toward the developer holding body are formed in a spiral shape around a rotation axis, and are rotated by the rotation axis. A first spiral blade that conveys the developer in the rotation axis direction, and a spiral shape around the rotation axis in a phase different from that of the first spiral blade. The rotation of the rotation axis causes the developer to rotate in the rotation axis direction. Each of the first spiral blade and the second spiral blade that conveys the second spiral blade, and the first spiral blade and the second spiral blade are discontinuous in the axial direction. The second spiral blade is smaller than the first spiral blade overlapping the first spiral blade on a cross section in a direction orthogonal to the rotation axis. has a diameter, the developer has remained the discontinuities, Ri by the rotation of the rotary shaft During the rotation, the developing agent transported by the second spiral blade, divided into a developer remaining in the discontinuity without being conveyed, the developer has remained the discontinuity without being conveyed , A conveying member that is mixed with a developer to be subsequently conveyed by the second spiral blade by the rotation of the rotating shaft and is conveyed, and a developer provided upstream of the conveying member in the developer conveying direction. And a developer replenishing section that operates.

According to a sixth aspect of the present invention, a developer holding body that holds a developer and a developer that is conveyed toward the developer holding body are formed in a spiral shape around a rotation axis, and are rotated by the rotation of the rotation axis. A first spiral blade that conveys the developer in the rotation axis direction, and a spiral shape around the rotation axis in a phase different from that of the first spiral blade. The rotation of the rotation axis causes the developer to rotate in the rotation axis direction. Each of the first spiral blade and the second spiral blade that conveys the second spiral blade, and the first spiral blade and the second spiral blade are discontinuous in the axial direction. The second spiral blade is smaller than the first spiral blade overlapping the first spiral blade on a cross section in a direction orthogonal to the rotation axis. has a diameter, the developer has remained the discontinuities, Ri by the rotation of the rotary shaft During the rotation, the developing agent transported by the second spiral blade, divided into a developer remaining in the discontinuity without being conveyed, the developer has remained the discontinuity without being conveyed , A conveying member that is mixed with a developer to be subsequently conveyed by the second spiral blade by the rotation of the rotating shaft and is conveyed, and a developer provided upstream of the conveying member in the developer conveying direction. And an image forming unit for forming an image on the supplied recording medium.

According to the present invention according to claims 1 to 4 , the stirring performance of the developer can be improved as compared with the case where the plurality of spiral blades have the same diameter.

According to the fifth aspect of the present invention, it is possible to provide a developing device capable of improving the stirring performance of the circulating developer and the replenished developer as compared with the case where the configuration of the present invention is not provided. it can.

According to the sixth aspect of the present invention, it is possible to provide an image forming apparatus including a developing device having improved developer agitation performance as compared with the case where the configuration of the present invention is not provided.

1 is a cross-sectional view showing an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing a developing device according to an embodiment of the present invention. It is the sectional view on the AA line in FIG. FIG. 3 is a perspective view showing a developer stirring / transporting member according to an embodiment of the present invention. FIG. 5 is a schematic diagram for explaining the configuration of the developer stirring / transporting member shown in FIG. 4. 5A and 5B are schematic diagrams for explaining the configuration of the developer stirring / conveying member shown in FIG. 4, in which FIG. 4A is a schematic diagram showing a rotation direction and an angular region of the developer stirring / conveying member, and FIG. It is a schematic diagram which shows the existence angle area | region of a spiral blade. FIG. 5 is a schematic diagram for explaining a mechanism in which a developer is conveyed by using the developer stirring / conveying member shown in FIG. 4.

Next, one mode for carrying out the present invention will be described with reference to the drawings.
FIG. 1 shows a sectional view of an image forming apparatus 10 as an embodiment of the present invention.

  The image forming apparatus 10 has an image forming apparatus main body 12.

The upper surface of the image forming apparatus main body 12 is used as a discharge unit 14 from which a recording medium having an image formed thereon is discharged.
In the image forming apparatus main body 12, an image forming unit 16 that forms an image to be transferred onto a recording medium, a recording medium supply device 18 that supplies the recording medium to the image forming unit 16, and a supply from the recording medium supply device 18. A transport path 20 for transporting the recorded recording medium to the discharge unit 14 is provided.

  The image forming unit 16 includes, for example, four developer image forming units 22Y, 22M, 22C, 22K, an optical writing device 24, and a transfer device 26.

The developer image forming portions 22Y, 22M, 22C, and 22K form developer images using Y (yellow), M (magenta), C (cyan), and K (black) developers, respectively.
Note that, hereinafter, Y, M, C, and K corresponding to each color may be omitted and generically referred to as the developer forming unit 22. The same applies to other configurations (photoconductor unit 28, developing device 30, etc.) corresponding to each color.

  The developer image forming units 22Y, 22M, 22C, 22K respectively include photoconductor units 28Y, 28M, 28C, 28K and developing devices 30Y, 30M, 30C, 30K.

The photoconductor units 28 are arranged in order of the photoconductor units 28Y, 28M, 28C, and 28K from the rear side (left side in FIG. 1) of the image forming apparatus main body 12.
Each of the photoconductor units 28Y, 28M, 28C, 28K is used as an image forming structure, and each of them has a photoconductor drum 32Y, 32M, 32C, 32K.
The photoconductor drum 32 is used as an image carrier.

  The developing devices 30Y, 30M, 30C, and 30K develop the latent images formed on the corresponding photoconductor drums 32Y, 32M, 32C, and 32K by using the developers of Y, M, C, and K stored therein, respectively. .

  The optical writing device 24 is used as a latent image forming device, and irradiates the photoconductor drum 32 with light to form a latent image on the surface of each of the photoconductor drums 32Y, 32M, 32C, and 32K.

  The transfer device 26 includes an intermediate transfer belt 34 used as a transfer member, primary transfer rolls 36Y, 36M, 36C and 36K used as primary transfer devices, and a secondary transfer roll 38 used as a secondary transfer device. And a cleaning device 40.

  The intermediate transfer belt 34 has an endless shape, and is supported by, for example, five support rolls 34a, 34b, 34c, 34d, and 34e so as to be rotatable in a direction indicated by an arrow in FIG. At least one of the support rolls 34a, 34b, 34c, 34d, and 34e is connected to a motor (not shown), and rotates by receiving drive transmission from this motor, thereby rotationally driving the intermediate transfer belt 34. Let

  The primary transfer rolls 36Y, 36M, 36C, and 36K intermediately transfer the developer images formed on the surfaces of the photoconductor drums 32Y, 32M, 32C, and 32K by the corresponding developing devices 30Y, 30M, 30C, and 30K. Transfer to the belt 34.

  The secondary transfer roll 38 transfers the Y, M, C, and K developer images transferred onto the intermediate transfer belt 34 onto a recording medium.

  The cleaning device 40 scrapes off the toner constituting the developer of each color remaining on the surface of the intermediate transfer belt 34 after the developer image of each color is transferred onto the recording medium by the secondary transfer roll 38. 42. The toner scraped off by the scraping member 42 is collected in the main body of the cleaning device 40.

  Further, in the image forming apparatus main body 12, there is provided a fixing device 44 that fixes the developer image transferred onto the recording medium by the secondary transfer roll 38 onto the recording medium.

  The recording medium supply device 18 extracts the recording medium storage container 46 that stores the recording media in a stacked state and the highest recording medium stored in the recording medium storage container 46, and extracts the extracted recording medium from the image forming unit 16 And a feeding roll 50 that feeds the recording medium fed from the feeding roll 48 and a recording medium, and the recording medium is fed to the image forming unit 16 in a state in which a plurality of recording media overlap each other. And a retard roll 52 for preventing this.

  The transport path 20 includes a main transport path 54 and a reverse transport path 56.

  The main conveyance path 54 conveys the recording medium supplied from the recording medium supply device 18 to the image forming unit 16, and ejects the recording medium on which the image is formed to the ejection unit 14. Along the main transport path 54, a delivery roll 48, a transport roll 50, a retard roll 52, a resist roll 58, a transfer unit 60, a fixing device 44, and a discharge roll 62 in order from the upstream side in the recording medium transport direction. Are arranged.

  The resist roll 58 adjusts the timing (timing) when the recording medium is conveyed to the transfer unit 60. The resist roll 58 temporarily stops the leading end of the recording medium conveyed from the recording medium supply device 18 side, and sends the recording medium toward the transfer unit 60 so as to coincide with the timing of image formation.

  The fixing device 44 has a heating roll 44a and a pressure roll 44b, and heats and pressurizes the recording medium passing between the heating roll 44a and the pressure roll 44b to fix the developer image on the recording medium. To do.

  The discharge roll 62 discharges the recording medium having the developer fixed by the fixing device 44 to the discharge unit 14.

The reverse conveyance path 56 is reversed so that the developer image is transferred to one surface of the recording medium by the transfer unit 60, and then the developer image is transferred to the surface opposite to this surface, and the resist roll 58 is again used. It is used as a transport path for transporting this recording medium toward.
For example, two reversing conveyance rolls 64a and 64b are arranged along the reversing conveyance path 56.

  When performing double-sided printing, the recording medium conveyed from the main conveyance path 54 to the discharge roll 62 is reversed by the discharge roll 62 being reversely rotated with the rear end thereof being sandwiched by the discharge roll 62. It is supplied to the transport path 56. The recording medium supplied to the reverse transport path 56 is transported to a position upstream of the registration roll 58 by the reverse transport rolls 64a and 64b.

Next, the details of the developing device 30 will be described. Note that the developing devices 30Y, 30M, 30C, and 30K have the same configuration although the corresponding colors are different, and will be described below as the developing device 30.
2 shows a sectional view of the developing device 30, and FIG. 3 shows a sectional view taken along the line AA of FIG.

  The developing device 30 is a two-component developing device that develops a latent image using a two-component developer composed of toner and carrier, has a developing device main body 66, and the developer is stored in the developing device main body 66. ing.

  A developing roll 68 used as a developer holder is mounted in the developing device main body 66. The developing roller 68 rotates in the direction of the arrow shown in FIG. 2 to supply the developer held on the surface to the photoconductor drum 32 (see FIG. 1), and to form the latent image formed on the surface of the photoconductor drum 32. develop.

The inside of the developing device main body 66 is partitioned into two spaces by, for example, one partition member 70, and the partitioned spaces serve as developer transport paths 72 and 74, respectively. The developer carrying paths 72, 74 are used as paths for carrying the developer in the developing device main body 66.
In the developer transport paths 72, 74, developer stirring transport members 76, 78 as transport members for transporting the developer while stirring are mounted, respectively.

Here, the developer stirring / conveying member 76 is a supply auger provided on the developing roll 68 side and having a developer supplying function to the developing roll 68 in addition to the toner stirring / mixing function.
The developer stirring / conveying member 78 is an admix (stirring) auger that stirs and mixes the toner replenished with the existing two-component developer.

A developer replenishment port 79 is opened on the upstream side of the developer transport path 74 of the developing device main body 66, and a toner concentration sensor (not shown) is disposed on the downstream side.
The toner T is supplied from the developer replenishing section 81 into the developing device main body 66 through the developer replenishing port 79, and is circulated and conveyed while being agitated and mixed by the developer agitating and conveying members 76 and 78. It

  FIG. 4 is a perspective view of the developer stirring / conveying member 78, and FIG. 5 is a schematic diagram for explaining the configuration of the developer stirring / conveying member 78. FIG. It is the figure approximated to the shape, and (b) is a figure showing the section of the AA line sectional view of (a).

  The developer agitating / conveying member 78 is formed with a shaft 84, which is a rotating shaft, in a spiral shape around the shaft 84, and has a first spiral blade 86 a and a first spiral blade 86 a that have overlapping portions in a cross section orthogonal to the shaft 84. It has a two-row spiral blade consisting of two spiral blades 86b. An upstream side of the developer stirring / transporting member 78 in the developer transporting direction is formed by a single-thread spiral blade 85. The developer stirring / conveying member 78 conveys the developer in the conveying direction by the rotation of the shaft 84.

  The diameter of the second spiral blade 86b is smaller than that of the first spiral blade 86a.

  The first spiral blade 86a and the second spiral blade 86b are formed at the same pitch with respect to the rotary shaft 84, and are arranged so that the phases around the rotary shaft 84 are different from each other by 180 °.

  In the portion where the first spiral blade 86a and the second spiral blade 86b are provided so as to overlap with each other, discontinuous portions FR in which these spiral blades are discontinuous in the axial direction are periodically formed.

  FIG. 6A is a schematic diagram showing the rotation direction and the angular region of the developer stirring and conveying member 78, and FIG. 6B is a schematic diagram showing the existing angular region of the spiral blade along the axial direction. .

  As schematically shown in FIG. 6A, the rotation directions of the first spiral blade 86a and the second spiral blade 86b according to the present embodiment are counterclockwise as viewed from BB in FIG. And the existing regions of the first spiral blade 86a and the second spiral blade 86b are set as shown in FIG. 6 (b). Here, the horizontal axis of FIG. 6B shows the position in the axial direction, and the vertical axis of FIG. 6B shows the first spiral blade when the angle region is set as shown in FIG. 6A. 86a, the existence angle region of the second spiral blade 86b is shown. Of the two spiral blades 86, the thick line in FIG. 6B indicates the first spiral blade 86a, and the thin line indicates the second spiral blade having a 180 ° attachment phase different from that of the first spiral blade 86a. 86b is shown.

  As shown in FIG. 6B, in the discontinuous portion FR (in this example, four positions of X (4), X (8), X (12), and X (16) in the figure), The first spiral blade 86a and the second spiral blade 86b, which face each other across the continuous portion FR, have a phase difference of 90 ° between the upstream end portions 86au and 86bu and the downstream end portions 86ad and 86bd of the first spiral blade 86a and the second spiral blade 86b. It is arranged so that it is displaced. For example, in the discontinuous portion FR (4) at X (4), the upstream side end portion 86au of the first spiral blade 86a is arranged so as to exist at the position of 90 °, whereas the downstream side end portion is arranged. 86ad is arranged at a position of 180 °, and the mounting phase difference between them is set to 90 °. Further, while the upstream end portion 86bu of the second spiral blade 86b is arranged so as to exist at the position of 270 °, the downstream end portion 86bd is arranged at the position of 360 ° (0 °). They are arranged so that the mounting phase difference between them is 90 °. Similarly, in the other discontinuous portions FR (8), FR (12), FR (16), the upstream side end portions 86au, 86bu of the respective spiral blades 86a, 86b facing each other with the discontinuous portion FR interposed therebetween and the downstream side are also provided. It is set and arranged so that the mounting phases of the end portions 86ad and 86bd differ by 90 °.

  Further, the upstream end portion 84au of the first spiral blade 86a and the downstream end portion 86bd of the second spiral blade 86b, which face each other across the discontinuous portion FR, are out of phase with each other by 90 ° (shifted by 90 °). It is arranged like so). For example, in the discontinuous portion FR (4) at X (4), the upstream end portion 86au of the first spiral blade 86a is arranged so as to exist at a position of 90 °, whereas the second spiral blade 86a has the second spiral portion 86au. The downstream end 86bd of the blade 86b is arranged at a position of 0 ° (360 °), and the mounting phase difference between them is set to 90 °. Further, while the upstream end portion 86bu of the second spiral blade 86b is arranged so as to exist at the position of 270 °, the downstream end portion 86ad of the first spiral blade 86a is located at the position of 180 °. And the mounting phase difference between them is set to 90 °. Similarly, in the other discontinuous portions FR (8), FR (12), FR (16), the upstream end portion 86au and the downstream end portion of the spiral blades 86a, 86b that face each other with the discontinuous portion FR in between. 86bd, the upstream side end portion 86bu and the downstream side end portion 86ad are set and arranged so that the mounting phase differs by 90 °.

  That is, spiral blades having the same diameter are set and arranged so as to overlap each other with the mounting phase being different by 90 ° across the discontinuous portion FR, and spiral blades having the same diameter are set and arranged close to each other across the discontinuous portion FR. .

  That is, the developer stirring / conveying member 78 according to the present embodiment has two spiral blades 86a and 86b whose phases are different by 180 °, and the spiral blades 86a and 86b facing each other in the discontinuous portion FR. It is set and arranged so that the phases of the end portions differ by 90 °.

  Compared with the structure in which a plurality of multiple spiral blades are provided and one single spiral blade is provided, the transport surface for transporting the developer is doubled in the cross section orthogonal to the axial direction, and the transport ability of the developer in the axial direction is doubled. Is increased.

Next, the conveyance of the developer by the developer agitating and conveying member 78 will be described based on FIGS. 6 and 7 described above.
FIG. 7 shows that the developer stirring / conveying member 78 is conveyed by the spiral blade in the states of 1/4 rotation, 1/2 rotation, 3/4 rotation, and 1 rotation with respect to the rotation axis direction of the developer stirring / conveying member 78. It is the figure which showed the developed developer typically.
Here, the developer conveyed by each of the first spiral blade 86a and the second spiral blade 86b of the developer stirring / conveying member 78 is transferred from the upstream side in the developer conveying direction (the right end in FIG. 7, X = 0) to D1. , D2, D3, D4.

(1) 1/4 Rotation The developer stirring / conveying member 78 rotates 1/4 rotation, and the developer is conveyed on the upstream side of the first spiral blade 86a on the upstream side in the developer conveying direction of the discontinuous portion FR (4). The agent D1, the developer D2 conveyed by the second spiral blade 86b, and the developer D4 conveyed by the first spiral blade 86a downstream of the discontinuous portion FR (4) in the developer conveying direction are ¼ pitch. Minutes are transported. In the developer D3, a part of the developer conveyed downstream of the first spiral blade 86a on the upstream side in the developer conveying direction of the discontinuous portion FR (4) is on the downstream side of the next second spiral blade 86b. Although transferred to the end portion 86bd and merged with the developer D4, the remaining first spiral blade 86a on the upstream side of the discontinuous portion FR (4) is interrupted at the upstream end portion 86au, and the discontinuous portion FR (4). Remains as the developer D3 without being conveyed.

(2) 1/2 rotation When the developer agitating / conveying member 78 is further rotated 1/4 rotation, the developer D3 remaining in the discontinuous portion FR (4) becomes the upstream side end of the next second spiral blade 86b. Although it is pushed out by the portion 86bu and conveyed, the developer D3 cannot be conveyed entirely because the outer diameter of the second spiral blade 86b is small. Therefore, the developer D3 is divided into the developer D3-1 that is conveyed by the second spiral blade 86b and the developer D3-2 that stays in place. Further, the developer D3-2 staying on the spot is mixed with the developer D2 conveyed to the second spiral blade 86b to become the developer D5 ((D3-2) + D2 = D5). , And remains in the discontinuous portion FR (4) as the developer D5. The developers D1, D3-1, D4 are conveyed by 1/4 pitch, respectively.

(3) 3/4 rotation Further 1/4 rotation, the second spiral blade 86b on the upstream side of the discontinuous portion FR (4) is interrupted at the upstream end portion 86bu, and becomes a discontinuous portion FR (4). The developer D5 remains without being conveyed. The developers D1, D3-1, D4 are conveyed by 1/4 pitch, respectively.

(4) One rotation When the developer D5 is further rotated 1/4 rotation, the downstream end portion 86ad of the first spiral blade 86a on the downstream side of the discontinuous portion FR (4) in the developer transport direction starts 1 /. It is transported for 4 pitches. The developers D1 and D3-1 are also conveyed by 1/4 pitch. The developer D4 remains in the discontinuous portion FR (8) without being conveyed as the developer D4.

  As described above, there is a partial difference in the time for delivering the developer D3 once retained at the discontinuous portion to the downstream spiral blade. As a result, while the developer stirring / conveying member 78 makes one rotation, even a developer located at the same position as the developer D3-1 and the developer D3-2 (D5) can be moved by a 1/2 pitch movement distance. There is a difference. That is, in the developing device, the speed of the developer conveyed by the double spiral blades having different diameters is differentiated to stir the developer, and the toner distribution in the axial direction is made uniform.

  In the present embodiment, the configuration having two spiral blades has been described, but the present invention is not limited to this and can be applied to a configuration having a plurality of spiral blades.

10 Image Forming Apparatus 12 Image Forming Apparatus Main Body 16 Image Forming Section 30 Developing Devices 76, 78 Developer Stirring Conveying Member 81 Developer Replenishing Section 84 Rotating Shaft 86a First Spiral Blade 86b Second Spiral Blade FR Discontinuous Section

Claims (6)

Provided in the developing device,
A first spiral blade that is formed in a spiral shape around a rotation axis and conveys the developer in the rotation axis direction by the rotation of the rotation axis ;
A second spiral blade that is spirally formed around the rotation axis in a phase different from that of the first spiral blade and that conveys the developer in the rotation axis direction by rotation of the rotation axis ;
Comprises a first helical blade and the second helical blade comprises a discontinuity that divides each of said said first spiral blade so that discontinuities in the axial direction the second spiral blade, the ,
The second spiral blade has a diameter smaller than that of the first spiral blade overlapping the first spiral blade on a cross section in a direction orthogonal to the rotation axis,
Developer has remained the discontinuities during one revolution of rotation Ri by the said rotary shaft, and the developer conveyed by the second helical blade remains in the discontinuous portion without being transported The developer, which is separated into the developer and remains in the discontinuous portion without being conveyed, is mixed with the developer to be subsequently conveyed by the second spiral blade by the rotation of the rotating shaft and is conveyed. Element.   2. The conveying member according to claim 1, wherein the end portions of the spiral blades on the upstream side and the end portions of the spiral blades on the downstream side sandwiching the discontinuous portion are arranged so that the phases around the rotation axis are different from each other by 90 °.   The conveying member according to claim 1, wherein the upstream spiral blade and the downstream spiral blade that are close to each other in the axial direction of the rotating shaft with the discontinuous portion interposed therebetween have the same diameter. The first spiral blade and the second spiral blade are arranged such that their phases are different by 180 ° in a cross section in a direction orthogonal to the rotation axis. The transport member described. A developer holder for holding the developer,
A first spiral blade that conveys the developer toward the developer holder, is formed in a spiral shape around a rotation axis, and conveys the developer in the rotation axis direction by the rotation of the rotation axis ; A second spiral blade that is spirally formed around the rotation axis in a phase different from that of the spiral blade and conveys the developer in the rotation axis direction by the rotation of the rotation axis ; the first spiral blade, and the second spiral blade. A spiral blade, and a discontinuity portion that divides each of the first spiral blade and the second spiral blade so as to be discontinuous in the axial direction, and the second spiral blade includes the first spiral blade and the second spiral blade . The developer that has a smaller diameter than the first spiral blade that overlaps the first spiral blade on the cross section in the direction orthogonal to the rotation axis and remains in the discontinuous portion is during the the O Ri 1 rotates in the rotation, the developing carried by the second spiral blade If divided into a developer remaining in the discontinuity without being conveyed, the developer has remained the discontinuity without being conveyed, then conveyed by the second spiral blade by rotation of said rotary shaft A transport member that is mixed with the developer to be transported, and
A developer replenishing section for replenishing the developer, which is provided on the upstream side in the developer conveying direction of the conveying member;
Developing device having. A developer holder that holds the developer, and the developer is conveyed toward the developer holder and is formed in a spiral shape around the rotation axis, and the developer is conveyed in the rotation axis direction by the rotation of the rotation axis. A first spiral blade; and a second spiral blade that is spirally formed around the rotation axis in a phase different from that of the first spiral blade and that conveys the developer in the rotation axis direction by rotation of the rotation axis . comprises a first helical blade and the second helical blade comprises a discontinuity that divides each of said said first spiral blade so that discontinuities in the axial direction the second spiral blade, the The second spiral blade has a diameter smaller than that of the first spiral blade overlapping the first spiral blade on a cross section in a direction orthogonal to the rotation axis, and the discontinuous portion developer which stayed in a, during one rotation Ri by the rotation of said rotary shaft, said second A developer transported by the spiral blade, divided into a developer remaining in the discontinuity without being conveyed, the developer said has remained in the discontinuity without being conveyed, said by the rotation of the rotary shaft first And a developer replenishment section provided on the upstream side of the conveyance member in the developer conveyance direction for replenishing the developer. A developing device,
An image forming unit that forms an image on the supplied recording medium,
An image forming apparatus having.

Images