JP2008032983A - Toner conveying device, developing device, and image forming apparatus provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently stir a toner and to improve the removal effect of the toner by toner removing members in constitution in which a spiral member is provided with the toner removing members. <P>SOLUTION: The toner conveying device includes a container 22 storing the toner, the spiral member 23, and a plurality of the toner removing members 36. The spiral member 23 comprises a rotatable shaft 32 disposed within the container 22 and blades 30 disposed on the peripheral surface of the shaft 32 and conveys the toner in an axial direction by rotating. The plurality of the toner removing members 36 are so disposed as to be contactable with the blade surfaces of the spiral member 23 and remove the toner sticking to the spiral member 23 by making elastic deformation due to the rotation of the spiral member 23. Then, the blades 30 are intermittently provided in the axial direction with a plurality of toner stagnating parts to make toner conveyance speed lower as compared with other portions. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a toner transport device, and more particularly to a toner transport device capable of suppressing aggregation of toner being transported. The present invention also relates to a developing device that performs development using a one-component toner (hereinafter sometimes simply referred to as “toner”), and in particular, a developing device that can suppress toner aggregation in the developing device, and The present invention relates to an image forming apparatus including the same.

  In general, image forming apparatuses such as electrophotographic developing printers, facsimiles, and copying machines are provided with a developing device that accommodates toner. By this developing device, a toner image is formed on the surface of the photoreceptor on which the electrostatic latent image based on the image data is formed.

  Here, the developing device is provided with a container for storing the toner, a developing roller rotatably provided in the container, a toner conveying member, and the like, but when the fluidity of the toner in the container is reduced, The toner transportability is lowered and the toner tends to stay in the container. As a result, the toner staying in the container aggregates due to long-term use, and the aggregated toner adheres to the toner conveying member having spiral blades. When the toner adheres to the toner conveying member in this way, there is a problem that even if the toner is stirred by the toner stirring member in the container, the aggregation state is not improved and an abnormal image such as a toner fog is generated. Such a problem is also a problem that occurs in a toner recycling mechanism in which, for example, toner remaining on the photosensitive member is removed by a cleaning device and then returned to the developing device via the transport device and reused. .

  Therefore, various image forming apparatuses for improving the above problems have been proposed. For example, in the apparatus disclosed in Japanese Patent Application Laid-Open No. 2004-177754, a rotationally propelled conveying means for returning the toner removed by the cleaning apparatus to the developing apparatus is shown. In this apparatus, the aggregation remaining in the recycled toner is shown. A toner breaking member for breaking the toner is provided. This toner breaker member is made of an elastic PET film sheet, and has a tongue piece that is deformed by applying a force from the outside when the rotationally propelling conveying means having a spiral shape is rotated. The aggregated toner is broken by the toner breaking member having the tongue piece.

However, in the above-described conventional image forming apparatus, the toner breaking member moves only in the traveling direction of the spiral blades of the rotationally propelled conveying means (that is, elastically deforms only in the longitudinal direction of the axis of the rotationally propelled conveying means). Therefore, the toner adhering to the spiral blades and shafts of the rotationally propelled conveying means cannot be scraped off sufficiently. As a result, the generation of aggregated toner cannot be sufficiently suppressed.
JP 2004-177754 A

  In order to solve the conventional problems as described above, the present applicant has already filed a toner conveying device that can effectively suppress the generation of aggregated toner (Japanese Patent Application No. 2005-089217). An example in which this toner conveying device is used in a developing device is shown in FIGS.

  FIG. 1 shows a photoreceptor 101 and a developing device 102 of an image forming apparatus. The developing device 102 includes a container 103, a developing roller 104, and first and second spiral members 105 and 106. Each spiral member 105, 106 includes rotatable shafts 105a, 106a and blades 105b, 106b provided on the peripheral surfaces of the shafts 105a, 106a. By rotating, the toner is conveyed in the longitudinal direction of each shaft. To do. A partition member 107 is provided between the first spiral member 105 and the second spiral member 106.

  A support member 110 is provided on the inner wall of the upper portion of the container 103. To the support member 110, toner removing members 111 and 112 for removing toner attached to the spiral members 105 and 106 are provided. Yes. As shown in FIGS. 1 and 2, each toner removing member 111, 112 is formed of an elastic metal wire, and its tip is provided so as to contact the surface of the corresponding spiral member 105, 106. ing. In FIG. 2, the first spiral member 105 and the toner removing member 111 provided corresponding to the first spiral member 105 are illustrated. The toner removing member 111 includes a plurality of toner removing members. Only one of these is shown and the others are omitted.

  In the configuration as described above, the toner attached to the spiral members 105 and 106 is removed by the toner removing member as follows.

  That is, as the spiral members 105 and 106 rotate, the spiral blades 105b and 106b apparently move in the longitudinal direction of the shafts 105a and 106a. Then, the lower end portions including the tip portions of the toner removing members 111 and 112 that are in contact with the spiral members 105 and 106 are pressed against the blades 105b and 106b while being elastically deformed by receiving the force from the blades 105b and 106b. By such contact of the toner removing members 111 and 112, the toner adhering to the spiral members 105 and 106 is scraped off.

  In the above configuration, the toner removal effect may not be sufficiently obtained depending on the shape and pitch of the blades of the spiral member and the mounting position and shape of the toner removal member. That is, the toner removing member 111 is elastically deformed as the spiral member 105 rotates, and the toner scraping portion on the tip side of the toner removing member 111 moves over the blade and moves to the opposite side as shown in FIG. May end up. Further, as shown in FIGS. 3A to 3D, when the spiral pitch of the blades is small, the moving stroke of the toner removing member 111 in the X direction (axial direction) is shortened, and the toner removing member 111 is removed. Movement is almost only in the Z direction in the figure. As a result, the toner adhering to the surface of the blade is scraped off in a circumferential shape, and the toner accumulates in the portion that is not scraped off. In this case, the toner conveying ability is lowered, and the toner cannot be sufficiently stirred in the container.

  An object of the present invention is to efficiently stir toner and improve the toner removing effect of the toner removing member in a configuration in which the toner removing member is provided on the toner conveying member.

  According to a first aspect of the present invention, a toner conveying device includes a container for storing toner, a conveying member, and a plurality of toner removing members. The conveyance member includes a rotatable shaft provided in the container and a toner conveyance unit provided on the peripheral surface of the shaft, and conveys the toner in the axial direction by rotating. The plurality of toner removing members are provided so as to be able to come into contact with at least the surface of the toner conveying portion of the conveying member, and are elastically deformed by the rotation of the conveying member to remove toner attached to the conveying member. The toner conveying portion of the conveying member is intermittently provided with a plurality of toner retaining portions that reduce the toner conveying speed as compared with other portions along the axial direction.

  In this toner conveying device, the conveying member rotates in the container, and thereby the toner is conveyed along the axial direction of the conveying member. Here, the plurality of toner removing members are provided so as to contact at least the surface of the toner conveying portion of the conveying member, and the toner adhered to the conveying member is removed by the plurality of toner removing members. Further, the toner transported by the transport member is retained due to a decrease in toner transport speed by a plurality of toner retaining portions provided intermittently in the axial direction. Then, the following toner collides with the staying toner, and the toner is mixed, so that the toner is efficiently stirred.

  According to a second aspect of the present invention, there is provided the toner conveying device according to the first aspect, wherein the toner conveying portion of the conveying member is an axially continuous or discontinuous blade formed on the peripheral surface of the shaft so as to protrude outward. The blade has at least a part thereof a large conveying force portion having a large toner conveying force and a small conveying force portion having a toner conveying force smaller than that of the large conveying force portion.

  In this conveying member, the small conveying force portion has a smaller toner conveying force than the large conveying force portion. Therefore, the toner moving speed is reduced in the small conveying force portion. That is, this small transport force portion functions as a toner retention portion. In addition, the toner removing member removes toner while being in contact with the large conveying force portion and the small conveying force portion of the blade, but in the small conveying force portion, the toner removing member is compared with the case where the toner removing member is in contact with the conventional blade. The elastic deformation is released as soon as possible.

  More specifically, in a conventional conveying member formed by blades of the same diameter, the toner removing member will continue to be elastically deformed in the axial direction until its tip is removed from the outer diameter of the blade. Depending on the case, as described above, the tip end side moves over the blade and moves to the opposite side. However, in the conveying member of the present invention, for example, in the small conveying force portion, when the outer diameter of the blade is made smaller than that of the other part to reduce the conveying force, all of the toner removal member comes into contact with the small diameter portion. Compared with the case of the same diameter, the contact of the toner removing member with the blade is released earlier, and the elastic deformation is released. For this reason, it is possible to prevent the front end side of the toner removing member from moving over the blades to the opposite side.

  According to a third aspect of the present invention, in the toner conveying device according to the second aspect, the toner conveying portion of the conveying member has a spirally formed blade, and the blade has a plurality of defective portions partially missing. In this case, the missing portion functions as a small conveying force portion in the blade of claim 2.

  According to a fourth aspect of the present invention, in the toner conveying device according to the second aspect, the toner conveying portion of the conveying member is a plurality of semicircular blades. In this case, the plurality of blades are formed in a semicircular shape, and the portion where the semicircle is formed functions as a large conveying force portion of the blade in the apparatus of claim 2, and the portion where the semicircle is not formed It functions as a small conveying force part of the blade.

  According to a fifth aspect of the present invention, in the toner conveying device according to the second aspect, the toner conveying portion of the conveying member is a circular blade provided eccentrically with respect to the shaft. In this case, the circular blade is provided eccentric to the shaft, and a portion of the circular blade that protrudes outward from the shaft functions as a large conveying force portion of the blade in the apparatus of claim 2. The part on the opposite side functions as a small conveying force part.

  According to a sixth aspect of the present invention, in the toner conveying apparatus according to the first to fifth aspects, the plurality of toner removing members are formed of a metal wire that can be elastically deformed.

  In this case, as compared with the PET film sheet of the prior art, durability against the force applied when the conveying member rotates is improved, so that the life of the toner removing member can be extended.

  According to a seventh aspect of the present invention, in the toner conveying device according to any one of the first to sixth aspects, the toner removing member extends from the side away from the axis of the conveying member so as to approach the axis and can contact the surface of the conveying member. It has a toner scraping part.

  In this case, when the conveying member rotates, the toner scraping portion of the toner removing member is in contact with the surface of the conveying member, so that the tip side moves together with the toner in the toner conveying direction. While the scraping portion is twisted and elastically deformed, the toner adhering to the surface of the conveying member is scraped off. Here, it is possible to realize an elastically deformable toner removing member with a simple configuration.

  According to an eighth aspect of the present invention, in the apparatus of the seventh aspect, the shape of the toner scraping portion is substantially elliptical.

  According to a ninth aspect of the present invention, there is provided a toner conveying device according to any one of the first to eighth aspects, further comprising a support member disposed along the axial direction of the conveying member, wherein the toner removing member is a blade adjacent to the conveying member. And a plurality of toner scraping portions that can be brought into contact with the surface of the conveying member, and a support portion that supports the plurality of toner scraping portions on the support member.

  According to a tenth aspect of the present invention, there is provided a developing device for forming a toner image on an image carrier provided in an image forming portion of an image forming apparatus, a container for storing toner, an image supported and supported in the container. A developing roller for supplying toner to the carrier, a conveying member, and a plurality of toner removing members are provided. The conveyance member includes a rotatable shaft provided in the container and a toner conveyance unit provided on the peripheral surface of the shaft, and conveys the toner in the axial direction by rotating. The plurality of toner removing members are provided so as to be able to come into contact with at least the surface of the toner conveying portion of the conveying member, and are elastically deformed by the rotation of the conveying member to remove toner attached to the conveying member. The toner conveying portion of the conveying member is intermittently provided with a plurality of toner retaining portions that reduce the toner conveying speed as compared with other portions along the axial direction.

  An image forming apparatus according to an eleventh aspect includes a paper storage unit that stores paper, a paper feed unit that feeds paper from the paper storage unit, a paper transport unit that transports paper from the paper feed unit, and a paper transport unit An image forming unit that forms a toner image on the conveyed paper; and a fixing unit that fixes the toner image on the paper formed by the image forming unit. The image forming unit includes an image carrier on which an electrostatic latent image is formed on the surface based on image information, and a developing device for forming a toner image on the image carrier. The developing device includes a container for storing toner, a developing roller supported in the container for supplying toner to the image carrier, a conveying member, and a plurality of toner removing members. The conveyance member includes a rotatable shaft provided in the container and a toner conveyance unit provided on the peripheral surface of the shaft, and conveys the toner in the axial direction by rotating. The plurality of toner removing members are provided so as to be able to come into contact with at least the surface of the toner conveying portion of the conveying member, and are elastically deformed by the rotation of the conveying member to remove toner attached to the conveying member. The toner conveying portion of the conveying member is provided with a toner retaining portion that intermittently decreases the toner conveying speed as compared with other portions along the axial direction.

  In the present invention as described above, in the configuration in which the toner removing member is provided on the toner conveying member, the toner can be efficiently stirred and the toner removing effect by the toner removing member can be improved.

[overall structure]
FIG. 4 shows an image forming apparatus according to an embodiment of the present invention. The image forming apparatus 1 includes a sheet feeding unit 2 disposed at a lower portion of the image forming apparatus main body 1 a, a sheet conveying unit 3 disposed on the side and above the sheet feeding unit 2, and an upper side of the sheet conveying unit 3. An image forming unit 4 disposed on the image forming unit 4, a fixing unit 5 disposed on the discharge side of the image forming unit 4, and an image reading unit 6 disposed above the image forming unit 4 and the fixing unit 5. Yes.

  The paper feed unit 2 includes a plurality of paper feed cassettes 7 in which paper 9 is accommodated, and the paper 9 is fed from the selected paper feed cassette 7 among the plurality of paper feed cassettes 7 by the rotation of the paper feed roller 8. The paper 9 is sent to the paper transport unit 3 side, and the paper 9 is surely fed to the paper transport unit 3 one by one. These four paper feed cassettes 7 are detachable from the image forming apparatus main body 1a.

  The paper 9 fed to the paper transport unit 3 is transported toward the image forming unit 4 via the paper supply path 10. The image forming unit 4 forms a predetermined toner image on a sheet 9 by an electrophotographic process, and includes a photoconductor 11 that is rotatably supported in a predetermined direction (the direction of an arrow X in the drawing). In addition, a charging device 12, an exposure device 13, a developing device 14, a transfer device 15, a cleaning device 16, and a charge eliminating device 17 are provided around the photoconductor 11 along the rotation direction.

  The sheet 9 on which the toner image is transferred by the image forming unit 4 is conveyed from the image forming unit 4 to the fixing unit 5. The fixing unit 5 includes a heating roller 18 and a pressure roller 19, and the toner image is fixed on the paper 9 by both rollers 18 and 19. Next, the sheet 9 on which the image is formed in the fixing unit 5 from the image forming unit 4 is discharged onto the discharge tray 21 by the discharge roller pair 20.

[Developer]
FIG. 5 shows the developing device 14. The developing device 14 includes a container 22 that receives toner supply and stores toner. The container 22 has a stirring chamber 22a for stirring the toner and a developing chamber 22b in which a developing roller 27 described later for guiding the toner onto the surface of the photoreceptor 11 is installed. Further, the developing device 14 includes a first spiral member 23 and a second spiral member 24 as conveying members. Further, a partition member 34 is provided between the first spiral member 23 and the second spiral member 24 so as to allow the stirring chamber 22a and the developing chamber 22b to communicate with each other. Yes. The partition member 34 is formed by extending the bottom surface of the container 22 upward.

  An opening 22c is formed on the photosensitive body 11 side of the container 22 along the longitudinal direction of the container 22, and a developing roller 27 including a fixed magnet roller and a nonmagnetic developing sleeve is provided in the opening 22c portion. Yes. The developing sleeve includes a fixed magnet roller and is rotatably supported to guide the toner stored in the container 22 onto the surface of the photoreceptor 11.

  Further, a magnetic blade 28 and a magnetic seal member (not shown) are provided inside the container 22. The magnetic blade 28 is made of a plate-like magnetic body, and is arranged so that the tip is close to the surface of the developing roller 27. The magnetic seal member is provided at the end of the developing roller 27 in the longitudinal direction.

  A toner replenishing hole 22d is opened on the upper surface of the container 22 above the first spiral member 23, and toner can be charged by the toner cartridge through the toner replenishing hole 22d. The charged toner is transported while being stirred in the stirring chamber 22a from one end side to the other end side by the first spiral member 23, and then transported to the developing chamber 22b. The toner conveyed to the developing chamber 22 b is conveyed while being stirred in the reverse direction in the developing chamber 22 b by the second spiral member 24, and is guided to the developing roller 27. The thickness of the toner guided to the developing roller 27 is regulated by a magnetic blade 28 that acts as a toner layer thickness regulating member. Thereafter, the toner carried on the surface of the developing roller 27 is guided to the developing position, that is, on the surface of the photoreceptor 11.

  The developing roller 27 is set to a predetermined peripheral speed, and is set to rotate in the same direction between the drum and the roller with respect to the rotation direction X of the photoconductor 11. Further, the developing roller 27 is arranged at a predetermined distance from the photoconductor 11.

[Spiral material]
The first spiral member 23 and the second spiral member 24 are disposed substantially in parallel. The first spiral member 23 includes a shaft 32 that is a rotatable first shaft provided in the stirring chamber 22a, and a spiral blade 30 provided on the peripheral surface of the shaft 32, and an arrow A in the drawing. , The toner is conveyed in the longitudinal direction of the shaft 32. Further, the developing device 14 includes a second spiral member 24. The second spiral member 24 is provided in the developing chamber 22 b, and a shaft 33, which is a rotatable second shaft disposed substantially parallel to the shaft 32, and a spiral blade 31 provided on the peripheral surface of the shaft 33. The toner is conveyed in the longitudinal direction of the shaft 33 by rotating in the direction of arrow B in the figure.

  FIG. 6 shows a partial external perspective view of the first spiral member 23. Since the basic configuration of the first spiral member 23 and the second spiral member 24 is the same, the first spiral member 23 will be described in detail below.

  As described above, the first spiral member 23 includes the shaft 32 and the spiral blade 30. Unlike the conventional spiral member, the spiral blade 30 is not formed with continuous blades. In other words, the blade 30 is formed with a plurality of defective portions intermittently formed in the axial direction.

  More specifically, referring to FIG. 6, the spiral blade 30 includes a portion 30 a formed without a defect continuously over one cycle (range of 360 degrees), followed by a half cycle (180 degrees). The range 30) is formed by repeating the configuration of a missing part 30b, a part 30a continuously formed over one cycle following the missing part 30b, and a subsequent missing part 30b. As described above, the spiral blade 30 is formed by repeatedly forming the large-diameter portion (large conveying force portion) 30a that is not missing and the missing small-diameter portion (small conveying force portion) 30b. In the missing small-diameter portion 30b, the toner conveyance capability is reduced as compared with the large-diameter portion 30a, and the toner moving speed is reduced in this portion. That is, the small-diameter portion 30b with missing blades becomes a toner retaining portion where toner stays. As a result, the spiral member 23 intermittently moves a plurality of toner retaining portions that reduce the toner conveyance speed along the axial direction. Will have.

[Toner removing member]
As shown in FIGS. 5 and 7, in the present embodiment, toner removing members 36 and 37 for removing toner attached to both spiral members 23 and 24 are provided. FIG. 7 schematically shows the toner removal member and the spiral member. Since both the toner removing members 36 and 37 have basically the same structure, the toner removing member 36 provided on the first spiral member 23 side will be described below.

  The toner removing member 36 is formed of an elastic metal wire (for example, SUS304). The toner removing member 36 is provided in the container 22 so that at least a part of the distal end side contacts the surface of the first spiral member 23, and a proximal end side is provided on a support member 38 attached in the container 22. It becomes the structure supported. Further, as shown in FIG. 7, the toner removing member 36 is provided with a twisted portion 36 a, and the surface of the first spiral member 23 in the direction orthogonal to the longitudinal direction of the shaft 32 of the first spiral member 23. The contact portion 36b (hereinafter referred to as “toner scraping portion 36b”) is formed to have a substantially elliptical shape when viewed from the front. The elliptical toner scraping portion 36b is formed to extend from the support member 38 so as to approach the shaft 32, and the virtual plane of the toner scraping portion 36b is parallel to the shaft 32 of the first spiral member 23. Is arranged. In FIG. 7, only the toner removing member 36 is shown, but the toner removing member 37 has the same shape as the toner removing member 36.

[Remove toner]
Next, taking the toner removing member 36 as an example, the process of removing the toner attached to the first spiral member 23 will be described with reference to FIGS. In FIG. 8, for convenience of explanation, only one of the plurality of toner removing members 36 is shown, and the others are omitted.

  First, when the first spiral member 23 rotates, the spiral blade 30 apparently moves in the direction of the arrow C in the drawing of the shaft 32 with the rotation. Then, the toner adhering to the surface of the shaft 32 is scraped and removed by the tip of the toner scraping portion 36b that contacts the shaft 32 of the first spiral member 23, and the side portion of the toner scraping portion 36b is a blade. The toner adhering to the blade 30 is scraped off by contacting the surface of the blade 30 (FIG. 8A). At this time, the toner removing member 36 receives a force from the blade 30 and elastically deforms in the direction of arrow C (FIGS. 1A and 1B).

  Further, as the rotation of the first spiral member 23 proceeds, the spiral blade 30 apparently moves further in the direction of the arrow C. At this time, the tip of the toner removing member 36 reaches the small diameter part (deletion part) 30 b formed on the blade 30, and thus the toner scraping part 36 b of the toner removing member 36 is separated from the blade 30. As a result, the elastic deformation of the toner removing member 36 is released, and the end side of the toner removing member 36 moves in the direction D opposite to the arrow C ((d) in the figure). Thereafter, the same operation as described above is repeated ((e) and (f) in the figure).

  As described above, since the small-diameter portion 30b is formed on the blade 30 of the first spiral member 23, the degree of elastic deformation of the toner removing member 36 is compared with the case where the conventional small-diameter portion is not formed. Become smaller. For this reason, stress on the toner removing member 36 can be reduced, and the toner removing member 36 can be prevented from being excessively elastically deformed and the toner scraping portion 36b moving to the opposite side of the shaft 32. .

[Toner transport]
Here, paying attention to toner conveyance, since the small-diameter portion 30b is formed in the blade 30 of the first spiral member 23, the toner conveyance force in this portion is reduced. That is, the toner conveyance speed is reduced at the small diameter portion 30b, and the toner is temporarily retained. On the other hand, from the rear side, the next toner is conveyed by the large-diameter portion 30a with a normal conveyance force (conveyance speed). Accordingly, the toner staying in the small diameter portion 30b collides with the toner from the rear, and both are mixed. For this reason, the toner is sufficiently stirred, and the toner can be transported in the form of powder. In this manner, by forming the small diameter portion (toner retention portion) 30b in the spiral member, it is possible to improve the toner stirring performance and transport performance.

[Other Embodiments]
(A) Other embodiment about the blade | wing of a spiral member is shown in FIG.

  The spiral member 40 shown in FIG. 1A has a shaft 41 and a spiral blade 42. The blade 42 of the spiral member 40 has a large diameter portion 40a on one side of the shaft 41 and a small diameter portion 40b on the other side.

  The spiral member 44 shown in FIG. 6B has a shaft 45 and a spiral blade 46, and the blade 46 is formed in a substantially semicircular shape. It has a large diameter part and a small diameter part on the other side.

  The spiral member 48 shown in FIG. 6C includes a shaft 49 and a spiral blade 50 having a circular shape in the axial direction and provided eccentric to the shaft 49. Thus, by providing the axially circular blade 50 eccentrically with respect to the shaft 49, the blade 50 has a large diameter portion on one side of the shaft 49 and a small diameter portion on the other side. become.

  The spiral member 52 shown in FIG. 4D has a shaft 53 and a spiral blade 54. The vane 54 has a substantially circular large-diameter portion on one side of the shaft 53, and the other side has a small-diameter portion missing over an angular range of about 120 °.

  The spiral member 56 shown in FIG. 5E includes a shaft 57 and a spiral blade 58 having an elliptical shape when viewed in the axial direction and having the center aligned with the shaft 57. Also according to such an embodiment, the blades 58 have a large diameter portion on one side of the shaft 57 and a small diameter portion on the other side.

  (B) In each of the above embodiments, the spiral member has an example of having a spiral blade, but the blade of the spiral member of the present invention is not limited to a spiral shape. That is, the blades only need to constitute a large conveyance force portion having a large toner conveyance force and a small conveyance force portion having a toner conveyance force smaller than that of the large conveyance force portion, as shown in FIGS. A simple configuration may be used. In the examples shown in these drawings, the large conveyance force portion and the small conveyance force portion are not continuous and are configured independently. Further, in order to convey the toner, a plane for energizing the toner of each blade is disposed to be inclined with respect to the axial direction of the rotation shaft.

  In the blade shown in FIG. 10A, the large conveyance force portion 61 occupying an area of 180 degrees with respect to the shaft 60 and the small conveyance force portion 62 occupying an area of 90 degrees are axial directions of the shaft 60. And are alternately arranged. In addition, the figure on the left side of Fig.10 (a) is a side view of a conveyance screw.

  The large conveyance force unit 61 energizes and conveys toner in the right direction when the shaft 60 rotates clockwise in the side view. Further, the small conveying force unit 62 also energizes and conveys toner in the right direction. However, the large conveyance force unit 61 and the small conveyance force unit 62 have different conveyance forces. For example, when the shaft 60 is 0 ° to 180 °, the large conveyance force portion 61 has a higher toner conveyance force and a higher toner conveyance speed. Subsequently, since the small conveyance force unit 62 conveys the toner from 180 ° to 270 °, the conveyance force is lower than the conveyance force of the large conveyance force unit 61 and the conveyance speed is slow. From 270 ° to 360 °, the toner is not conveyed because the blade is missing. Even with such a configuration, since the toner conveyance force varies depending on the rotation angle of the shaft, a portion where the moving speed of the toner is fast and a portion where the toner is moving are generated. It is possible to prevent deterioration.

  Further, the blade shown in FIG. 10B has a large conveyance force portion 65 that occupies an area of 180 degrees with respect to the shaft 64, a small conveyance force portion 66 that occupies an area of 90 degrees, and 90 degrees. And a small transporting force portion 67 that occupies the same area.

  In this case, the large conveyance force portion 65 and the small conveyance force portions 66 and 67 urge the toner in the right direction and convey it. However, since the transport force of the large transport force unit 65 and the small transport force units 66 and 67 are different, the toner transport force varies depending on the angle of the shaft 64, and further, the transport by the large transport force unit 65 is changed to the small transport force unit 66. The toner transfer is temporarily stopped when shifting to the conveyance of the toner. Even with such a configuration, since the toner conveyance force varies depending on the rotation angle of the shaft, a portion where the toner conveyance speed is fast and a portion where the toner conveyance speed is low are generated, thereby realizing efficient stirring and prevention of toner deterioration. Can do.

  Further, in the blade shown in FIG. 10C, the large conveying force portion 70 occupying an area of 180 degrees with respect to the shaft 69 and the small conveying force portion 71 occupying an area of 90 degrees are alternately arranged. Has been.

  The large conveyance force unit 70 energizes and conveys toner in the right direction when the shaft 69 rotates clockwise in a side view. Further, the small conveyance force unit 71 energizes and conveys toner in the left direction. In this configuration, the urging direction is opposite, but the toner is conveyed in one direction because the toner conveying force by the large conveying force unit 70 is larger. Even with such a configuration, since the toner conveyance force varies depending on the rotation angle of the shaft, a portion where the toner conveyance speed is fast and a portion where the toner conveyance speed is low are generated, thereby realizing efficient stirring and prevention of toner deterioration. Can do.

  In the blade shown in FIG. 11A, two first and second large conveying force portions 73 and 74 occupying an area of 180 degrees with respect to the shaft 72 are arranged at the arrangement point 75 on the shaft. The toner is inclined with respect to the direction and is arranged to urge and convey the toner in the same direction by rotation.

  In the above configuration, the toner conveying force of the blades can be considered to be the same regardless of the rotation angle of the shaft 72. However, considering the position of the toner, the blades are changed according to the rotation angle of the shaft 72. The conveying force is different. That is, for example, the toner is moved to the right side of the drawing by the first large transport force unit 73. Subsequently, when the role of toner conveyance is changed to the second large conveyance force unit 74, the point 76 at which the second large conveyance force unit 74 starts conveyance by urging and the first large conveyance force unit 73 finishes conveyance. Since the point 77 is different, the second large transport force unit 74 is initially idle. (However, since there is actually toner transferred from the reverse direction of the transfer, there is no complete idling.) Even with such a configuration, the toner conveying force varies depending on the rotation angle of the shaft, so the toner A part having a high conveyance speed and a part having a low conveyance speed are generated, and efficient stirring and prevention of toner deterioration can be realized.

  Further, in the blade shown in FIG. 10B, the four first to fourth small conveying force portions 82 to 85 occupying an area corresponding to 90 degrees with respect to the shaft 81 are arranged on the shaft 81. , 87 have an inclination with respect to the axial direction and are arranged to convey toner in the same direction by rotation. Even in such a configuration, similarly to FIG. 10A, since the toner conveyance force varies depending on the rotation angle of the shaft, a portion where the toner conveyance speed is fast and a portion where the toner conveyance speed is low are generated. It is possible to prevent deterioration.

  Further, in the blade shown in FIG. 10C, the large conveying force portion 91 occupying an area of 180 degrees with respect to the shaft 90 is inclined with respect to the axial direction, and conveys toner in the same direction by rotation. It is arranged to do. In this configuration, for example, when the shaft 90 is 0 to 180 degrees, the large conveyance force unit 91 conveys the toner. On the other hand, since the blades are missing from the subsequent 180 degrees to 360 degrees, the toner is not conveyed. Even with such a configuration, since the toner conveyance force varies depending on the rotation angle of the shaft, a portion where the toner conveyance speed is fast and a portion where the toner conveyance speed is low are generated, thereby realizing efficient stirring and prevention of toner deterioration. Can do.

  (C) In the above embodiment, the toner removing member is applied to the toner conveying member of the developing device. However, the toner removing member may be applied to other toner conveying members such as a toner conveying member of the cleaning device.

  (D) In the above-described embodiment, a digital copying machine is shown as an example of an image forming apparatus, but other image forming apparatuses such as a facsimile and a printer may be used.

The figure which shows the image development apparatus as background art. The figure for demonstrating the problem of the toner removal member in background art. The figure for demonstrating the problem of the toner removal member in background art. 1 is a schematic diagram illustrating an overall configuration of an image forming apparatus in which an embodiment of the present invention is employed. FIG. 3 is a cross-sectional view of a developing device of the image forming apparatus. FIG. 3 is a partial external perspective view of a toner removing member provided in the developing device. FIG. 3 is a schematic diagram of the toner removing member. The figure which shows the effect | action of the said toner removal member. The figure which shows other embodiment. The figure which shows other embodiment. The figure which shows other embodiment.

Explanation of symbols

11 Photosensitive member 14 Developing device 22 Container 23, 24 Spiral member 30, 31 Blade 30b Defect portion 32, 33 Shaft 36, 37 Toner removing member 36b Toner scraping portion

Claims (11)

A container for storing toner;
A rotatable member provided in the container, and a toner conveying unit provided on a peripheral surface of the shaft, and a conveying member that conveys the toner in an axial direction by rotating;
A plurality of toner removing members provided so as to be able to contact at least the surface of the toner conveying portion of the conveying member, and elastically deforming by the rotation of the conveying member to remove the toner adhering to the conveying member;
With
The toner conveying portion of the conveying member is intermittently provided with a plurality of toner retaining portions that reduce the toner conveying speed as compared with other portions along the axial direction.
Toner transport device. The toner conveying portion of the conveying member is an axially continuous or discontinuous blade formed to protrude on the outer peripheral side on the peripheral surface of the shaft,
2. The blade according to claim 1, wherein at least part of the blade includes a large conveyance force portion having a large toner conveyance force and a small conveyance force portion having a toner conveyance force smaller than that of the large conveyance force portion. Toner transport device. The toner conveying portion of the conveying member has a spirally formed blade,
The blade has a plurality of deficient portions partially missing,
The toner conveying device according to claim 2.   The toner conveying device according to claim 2, wherein the toner conveying portion of the conveying member is a plurality of semicircular blades.   The toner conveying device according to claim 2, wherein the toner conveying portion of the conveying member is a circular blade provided eccentric to the shaft.   The toner conveying device according to claim 1, wherein the plurality of toner removing members are formed of an elastically deformable metal wire.   The toner removal member has a toner scraping portion that extends so as to approach the shaft from a side away from the shaft of the transport member and can come into contact with the surface of the transport member. The toner conveying device according to 1.   The toner conveying device according to claim 7, wherein the toner scraping portion has a substantially elliptical shape. A support member disposed along the axial direction of the transport member;
The toner removing member is inserted between adjacent blades of the spiral member and supports a plurality of toner scraping portions that can come into contact with the surface of the conveying member, and supports the plurality of toner scraping portions on the support member. Having a support part,
The toner conveying device according to claim 1. A developing device for forming a toner image on an image carrier provided in an image forming unit of an image forming apparatus,
A container for storing toner;
A developing roller supported in the container and for supplying toner to the image carrier;
A rotatable member provided in the container, and a toner conveying unit provided on a peripheral surface of the shaft, and a conveying member that conveys the toner in an axial direction by rotating;
A plurality of toner removing members provided so as to be able to contact at least the surface of the toner conveying portion of the conveying member, and elastically deforming by the rotation of the conveying member to remove the toner adhering to the conveying member;
With
The toner conveying portion of the conveying member is intermittently provided with a plurality of toner retaining portions that reduce the toner conveying speed as compared with other portions along the axial direction.
Development device. A paper storage unit for storing paper, and a paper feeding unit for feeding out the paper from the paper storage unit;
A paper transport unit for transporting paper from the paper feed unit;
An image forming unit that forms a toner image on a sheet conveyed from the sheet conveying unit;
A fixing unit for fixing a toner image on a sheet formed by the image forming unit;
With
The image forming unit includes an image carrier on which an electrostatic latent image is formed on the surface based on image information, and a developing device for forming a toner image on the image carrier,
The developing device includes:
A container for storing toner;
A developing roller supported in the container and for supplying toner to the image carrier;
A rotatable member provided in the container, and a toner conveying unit provided on a peripheral surface of the shaft, and a conveying member that conveys the toner in an axial direction by rotating;
A plurality of toner removing members provided so as to be able to contact at least the surface of the toner conveying portion of the conveying member, and elastically deforming by the rotation of the conveying member to remove the toner adhering to the conveying member;
With
The toner conveying portion of the conveying member is intermittently provided with a plurality of toner retaining portions that reduce the toner conveying speed as compared with other portions along the axial direction.
Image forming apparatus.

Images