JP2010151966A - Powder conveying apparatus, process unit, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a powder conveying apparatus for preventing retaining of powder in a powder delivery section between conveying means for conveying powder such as toner. <P>SOLUTION: This powder conveying apparatus includes a first powder conveying means 31 for conveying powder in one direction A, and a second powder conveying means 32 for receiving the powder from the first powder conveying means 31 and conveying powder in a direction B crossing the powder conveying direction A of the first powder conveying means 31. A stirring member 37 for stirring the powder is arranged in the powder delivery section D for delivering powder from the first powder conveying means 31 to the second powder conveying means 32. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a powder conveyance device, a process unit including the powder conveyance device, and an image forming apparatus.

  In image forming apparatuses such as copiers, printers, facsimiles, or multifunction peripherals thereof, toner remaining on the surface of an image carrier such as a photoconductor and an intermediate transfer belt is removed by a cleaning device, and then the toner is collected in a toner recovery unit. Many toner conveying means for conveying are used.

For example, the image forming apparatuses described in Patent Document 1 and Patent Document 2 include a transport screw and a transport belt as the toner transport unit. Specifically, the toner removed from the image carrier is conveyed in the axial direction by a conveying screw, and the toner is transferred to the conveying belt at the end of the conveying screw. Then, the toner is transported to the toner collecting unit by the transport belt.
JP 2007-206391 A Japanese Utility Model Publication No. 4-116867

  However, since the conveying belt is configured to convey the toner delivered from the conveying screw in a direction crossing the conveying direction by the conveying screw, the toner is likely to stay in the toner delivering portion. When the toner stays in the toner transfer portion and the staying toner is exposed to a high temperature and high humidity environment and solidifies, there is a problem that clogging (blocking phenomenon) occurs in the toner transport path and causes a transport failure.

  Further, when the toner stays in the transport path further, the transport screw is pressed by the staying toner, and the transport function of the transport screw is lowered. Further, since the conveying screw is bent due to the pressing force of the staying toner, the conveying screw may come into contact with the peripheral member and be damaged. It is also conceivable that toner leaks from the case forming the conveyance path.

  SUMMARY OF THE INVENTION In view of such circumstances, the present invention provides a powder conveying apparatus for preventing powder from staying in a powder delivery section between conveying means for conveying powder such as toner, a process unit using the same, and An image forming apparatus is to be provided.

  The first aspect of the present invention is the first powder conveying means for conveying the powder in one direction, and the powder conveying direction of the first powder conveying means when the powder is delivered from the first powder conveying means. In a powder conveying apparatus comprising a second powder conveying means for conveying powder in a direction intersecting with the powder, a powder delivery section for delivering powder from the first powder conveying means to the second powder conveying means Further, a stirring member for stirring the powder is provided.

  When the powder is conveyed by the first powder conveying means and the second powder conveying means, the powder is agitated by the agitating member, so that the powder can be smoothly conveyed without staying in the powder delivery portion. it can.

  According to a second aspect of the present invention, in the powder conveying device according to the first aspect, the stirring member has a rotating rotating portion and a plurality of convex portions disposed on the outer periphery of the rotating portion.

  By rotating the rotating part, the powder can be stirred by a plurality of convex parts.

  According to a third aspect of the present invention, in the powder conveying device according to the second aspect, the rotating portion is configured to be rotatable around an axis parallel to the powder conveying direction, and the rotating portion rotates at the convex portion. The powder feed surface is configured by inclining the surface facing forward in the direction so as to face the downstream side with respect to the powder transport direction.

  By rotating the rotating portion, the powder can be stirred by the plurality of convex portions, and the powder can be transported to the downstream side in the powder transport direction by the powder feeding surface formed on the convex portions. Thus, since powder can be conveyed, stirring, it becomes possible to prevent the retention of the powder in a powder delivery part more effectively.

  According to a fourth aspect of the present invention, in the powder conveying apparatus according to the third aspect, an inclination angle of the powder feeding surface with respect to the powder conveying direction is set to 5 ° or more and 30 ° or less.

  By setting the inclination angle of the powder feed surface with respect to the powder conveyance direction as described above, the powder stirring function and the powder conveyance function can be satisfactorily exhibited.

  Invention of Claim 5 is the powder conveying apparatus of any one of Claim 2-4, The area of the end surface of the powder conveyance direction downstream of the said convex part is the powder conveyance direction of the said convex part. It is larger than the area of the upstream end face.

  Thus, by setting the area of the end face of the convex portion, it is possible to suppress the powder from moving (reversely flowing) in the direction opposite to the powder conveyance direction.

  Invention of Claim 6 is the powder conveying apparatus of Claim 5, The height of the end surface of the powder conveyance direction downstream of the said convex part is made into the height of the end surface of the powder conveyance direction upstream of the said convex part. It is higher than that.

  Thus, by setting the height of the end face of the convex portion, it is possible to suppress the powder from moving (reversely flowing) in the direction opposite to the powder conveyance direction.

  A seventh aspect of the invention is the powder conveying apparatus according to any one of the second to sixth aspects, wherein at least one of the first powder conveying means and the second powder conveying means is a plurality of rotatable. An endless transport belt stretched by a support member, wherein the rotating portion of the stirring member is attached to one of the support members, and the rotating portion rotates integrally with the support member. It is a thing.

  Thereby, a support member and a rotation part can share a drive part, and it becomes possible to reduce a number of parts.

  The invention according to claim 8 is the powder conveying apparatus according to any one of claims 2 to 7, wherein the rotating portion and the convex portion are integrally configured.

  Since the rotating part and the convex part are integrally configured, such as part loss due to insufficient fixing when these are fixed to each other by another member, and decrease in powder transportability due to occurrence of sticking agent residue at the time of fixing, etc. Problems can be prevented.

  A ninth aspect of the present invention is the powder conveying apparatus according to any one of the second to eighth aspects, wherein the rotating portion and the convex portion are made of resin.

  Further, since the rotating part and the convex part are made of a resin, it is possible to make the corrosion difficult to occur. Thereby, the stirring function etc. of a stirring member can be maintained favorable.

  A tenth aspect of the present invention is the powder conveyance device according to any one of the second to ninth aspects, wherein the first powder conveyance unit is formed in a spiral shape for conveying the powder in the axial direction while rotating. It is a conveyance member, Comprising: The largest outer diameter part of the said convex part of the said stirring member is enlarged in the radial direction rather than the largest outer diameter part of the said conveyance member.

  By making the maximum outer diameter portion of the convex portion larger in the radial direction than the maximum outer diameter portion of the conveying member, the region where the powder can be stirred by the stirring member and the region where the powder can be conveyed by the first powder conveying means And the powder can be sufficiently stirred.

  An eleventh aspect of the invention is the powder conveying apparatus according to any one of the first to tenth aspects, wherein the first powder conveying means and the second powder conveying means are each formed in a spiral shape. A conveyor belt or a conveyor belt having a plurality of irregularities formed on the outer peripheral surface thereof, wherein the spirally formed portion of the first powder conveying means or the pitch of the irregularities is determined by the second powder conveying means. The part formed in the spiral shape or longer than the pitch of the unevenness.

  Thereby, the powder conveyance amount by the first powder conveyance means can be made smaller than the powder conveyance amount by the second powder conveyance means, and the retention of the powder in the powder delivery portion is effectively prevented. It is possible.

  A twelfth aspect of the present invention is the powder conveying apparatus according to any one of the first to eleventh aspects, wherein the first powder conveying means and the second powder conveying means are driven by the same drive unit. It is configured to convey powder.

  Thereby, the first powder conveying means and the second powder conveying means can share the drive unit, and the number of parts can be reduced.

  A thirteenth aspect of the present invention is the powder conveying apparatus according to any one of the first to twelfth aspects, wherein the powder is toner.

  The powder conveying device of the present invention can be applied to a toner conveying device that conveys toner.

  According to a fourteenth aspect of the present invention, in the process unit configured to be detachable from the image forming apparatus main body, the powder conveying apparatus according to any one of the first to thirteenth aspects is provided.

  It is possible to provide a process unit including the powder conveyance device according to any one of claims 1 to 13.

  A fifteenth aspect of the invention is an image forming apparatus provided with the process unit of the fourteenth aspect.

  An image forming apparatus including the process unit according to claim 14 can be provided.

  A sixteenth aspect of the present invention is the image forming apparatus according to the fifteenth aspect, comprising a plurality of the process units.

  An image forming apparatus including a plurality of process units according to claim 14 can be provided.

  According to the present invention, it is possible to prevent the powder from staying in the powder delivery section and prevent clogging (blocking phenomenon) of the powder in the conveyance path. Thereby, the conveyance property of powder can be maintained favorable and stably. Further, by preventing the powder from staying, it is possible to prevent the powder from leaking from the case forming the conveyance path. Moreover, since it is possible to prevent the conveying member from being pressed by the retained powder, it is possible to prevent deterioration of the conveying function due to the bending of the conveying member, breakage of the conveying member, and the like.

  FIG. 1 is a cross-sectional view showing an outline of a color image forming apparatus of the present invention. The main part of the image forming apparatus will be described below with reference to FIG. The image forming apparatus includes four process units 1K, 1C, 1M, and 1Y for forming images with developers of black, cyan, magenta, and yellow corresponding to color separation components of a color image. These process units 1K, 1C, 1M, and 1Y are detachably attached to the main body of the image forming apparatus, so that consumable parts can be replaced at a time.

  The process units 1K, 1C, 1M, and 1Y have the same configuration except that they store different color toners. Therefore, the configuration of one process unit will be described as an example. The symbols K, C, M, and Y that indicate the color distinction are omitted. The process unit 1 includes a photosensitive member 2 as an image carrier that carries an electrostatic latent image, a charging roller 3 as a charging unit that charges the surface of the photosensitive member 2, and an electrostatic latent image on the surface of the photosensitive member 2. A developing device 4 for supplying toner to form a toner image and a cleaning blade 5 as a cleaning unit for removing residual toner adhering to the surface of the photoreceptor 2 are provided.

  The image forming apparatus according to the present invention also uses an exposure device 7 that forms an electrostatic latent image on the surface of each photoconductor 2 and an image formed by the process units 1K, 1C, 1M, and 1Y on a recording medium such as paper. An intermediate transfer unit 8 for transferring, a fixing device 9 for fixing an image on the recording medium, and a recording medium supply unit 6 for supplying the recording medium are provided.

  The intermediate transfer unit 8 includes an intermediate transfer belt 12 formed of an endless belt that is stretched over a driving roller 10 and a driven roller 11. Four primary transfer rollers 13 are disposed on the inner peripheral surface of the intermediate transfer belt 12 as primary transfer means. Each primary transfer roller 13 is in pressure contact with the inner peripheral surface of the intermediate transfer belt 12 at a position facing each photoconductor 2. By this pressure contact, each photoreceptor 2 is pressed against the outer peripheral surface of the intermediate transfer belt 12, and a primary transfer nip is formed at the pressure contact portion.

  Further, a secondary transfer roller 14 as a secondary transfer unit is disposed opposite to the driving roller 10 that stretches the intermediate transfer belt 12. The secondary transfer roller 14 is in pressure contact with the outer peripheral surface of the intermediate transfer belt 12, and a secondary transfer nip is formed at the pressure contact portion. A belt cleaning device 21 for cleaning the surface of the intermediate transfer belt 12 is disposed on the outer periphery of the intermediate transfer belt 12.

  The fixing device 9 includes, for example, a fixing roller 9a having a heating source such as a heater and a pressure roller 9b in pressure contact with the fixing roller 9a. A fixing nip is formed at a pressure contact portion where the fixing roller 9a and the pressure roller 9b are in pressure contact with each other.

  The recording medium supply unit 6 includes a recording medium storage unit 16 that can store a large number of paper sheets as recording media, a supply roller 17 that feeds the recording medium from the recording medium storage unit 16, and the like. On the way from the supply roller 17 to the secondary transfer nip between the secondary transfer roller 14 and the driving roller 10, a pair of registration rollers 18 are provided for temporarily stopping the recording medium.

  Further, a pair of discharge rollers 20 for discharging the recording medium to the outside is disposed above the fixing device 9 in the drawing. The recording medium discharged by these discharge rollers 20 is configured to be stacked on a stock unit 19 formed by recessing the upper cover of the image forming apparatus main body inward.

The basic operation of the image forming apparatus will be described below with reference to FIG.
In one image forming unit 1K, the charging roller 3 charges the surface of the photoreceptor 2 to a uniform high potential. Based on the image data, the exposure device 7 irradiates the surface of the photoreceptor 2 with the laser beam L1, and the potential of the irradiated portion is lowered to form an electrostatic latent image. The toner charged by the developing device 4 is electrostatically transferred to the portion of the surface of the photoreceptor 2 where the electrostatic latent image is formed, and a toner image is formed (visualized). Similarly, toner images of the respective colors are formed on the photoreceptor 2 in the other process units 1C, 1M, and 1Y.

  The toner images formed on the respective photoreceptors 2 are sequentially superimposed and transferred onto the intermediate transfer belt 12 that circulates in the primary transfer nip. After the transfer, the residual toner adhering to the surface of each photoconductor 2 is removed by the cleaning blade 5.

  On the other hand, the recording medium accommodated in the recording medium accommodating portion 16 is sent out by the supply roller 17. The sent recording medium is temporarily stopped by the registration roller 18. Then, after the toner image is transferred to the intermediate transfer belt 12 as described above, the driving of the registration roller 18 is resumed, and the recording medium is transferred to the secondary transfer roller in synchronization with the toner image on the intermediate transfer belt 12. 14 to the secondary transfer nip between the drive roller 10 and the drive roller 10. Then, the toner image on the intermediate transfer belt 12 is transferred to the recording medium sent to the secondary transfer nip.

  The recording medium to which the toner image is transferred is conveyed to the fixing device 9. The recording medium sent to the fixing device 9 is sandwiched and heated and pressed by a fixing nip between the fixing roller 9a and the pressure roller 9b, and the toner image is fixed on the recording medium. Thereafter, the recording medium is discharged to the stock unit 19 by the discharge roller 20.

FIG. 2 is a schematic configuration diagram of the process unit 1 (1K, 1C, 1M, 1Y).
As shown in FIG. 2, the developing device 4 includes a developing container 23 that stores toner. The developing container 23 includes an unused toner storage unit 24 filled with unused toner, and a waste toner recovery unit 25 that stores used waste toner, and the unused toner storage unit 24 and the waste toner recovery unit 25. The space is isolated by a flexible partition member 26. Further, an agitator 30 for agitating the unused toner is disposed in the unused toner container 24.

  The partition member 26 is, for example, a plastic sheet-like member, and can be displaced to the unused toner storage unit 24 side and the waste toner collection unit 25 side. When the unused toner in the unused toner storage unit 24 decreases and the waste toner is collected in the waste toner collection unit 25, the partition member 23 is gradually pushed down by the weight of the collected waste toner. ing.

  A developing roller 27 that supplies toner to the photosensitive member 2, a toner supply roller 28 that supplies toner to the developing roller 27, and a developing roller 27 are carried in the opening of the developing container 23 facing the photosensitive member 2. A regulating blade 29 for forming toner in a uniform thin layer is provided.

  Further, as shown in FIG. 3, the process unit 1 includes a toner conveying device (powder conveying device) 22 for conveying the waste toner to the waste toner collecting unit 25. The toner conveying device 22 includes a conveying coil 31 disposed in the lower part of the process unit 1, a conveying belt 32 disposed in the vertical direction of the process unit 1, and an upper part of the process unit 1 in the figure. A conveying screw 33 is provided.

  In FIG. 2, a toner receiver 38 having an opening 38 a facing the cleaning blade 5 is disposed below the cleaning blade 5. The toner receiving portion 38 is disposed in the axial direction of the photosensitive member 2, and the transport coil 31 is accommodated in the toner receiving portion 38.

  As shown in FIG. 2, the conveying screw 33 is accommodated in the waste toner collecting unit 25. Further, a stirring screw 34 is disposed in the waste toner collecting unit 25 in parallel with the conveying screw 33.

  The conveyor belt 32 is constituted by an endless belt having a plurality of uneven portions formed on the outer peripheral surface. As shown in FIG. 3, the conveyance belt 32 is disposed in an annular path 39 formed in the case 101 that constitutes the process unit 1. Two support members 35 and 36 that rotate in the upper and lower portions of the annular path 39 in the figure are disposed, and the conveyor belt 32 is supported by these support members 35 and 36.

  As shown in FIG. 3, an opening 39 a formed by cutting out a part of the peripheral wall portion is provided in the upper portion of the peripheral wall portion forming the annular path 39. A toner receiver 40 is disposed below the opening 39a. The toner receiving portion 40 accommodates one end portion of the conveying screw 33 exposed from a waste toner collecting portion 25 (not shown).

  In the embodiment shown in FIG. 3, of the two support members 35 and 36 that support the transport belt 32, the lower support member 35 in the figure is connected to one end of the transport coil 31, and the upper support member in the figure. 36 is connected to one end of the stirring screw 34. Further, an end (not shown) of the stirring screw 34 is connected to the drive unit. When the agitating screw 34 is rotated by driving the drive unit, the conveyor belt 32 travels around via the upper support member 36 and the conveyor coil 31 rotates via the lower support member 35. ing. Further, the conveying screw 33 is interlocked and connected to the drive unit of the stirring screw 34 via a gear or the like. That is, the conveyance coil 31, the conveyance belt 32, the conveyance screw 33, and the stirring screw 34 share one drive unit, thereby reducing the number of parts. Note that these common driving units may be arranged at other positions. For example, it is also possible to provide a gear at an end (not shown) of the transport coil 31 and connect the gear and the driving unit of the photosensitive member.

  FIG. 4 shows a state in which the front side of the case 101 (see FIG. 3) in which the annular path 39 and the like are formed is closed by another case 102. In the lower part of the figure of the case 102 as the closing member, an inlet 41 for carrying toner is formed. On the other hand, an outlet 42 for carrying out the toner is formed in the upper portion of the case 102 in the figure. One end of the transport coil 31 is inserted into the inlet 41 and one end of the transport screw 33 is inserted into the outlet 42. Although not shown in FIG. 4, the photoreceptor 2, the developing device 4, and the like are disposed on the front side of the case 102 in the drawing.

  The toner transport path by the toner transport device 22 will be described. First, as shown in FIG. 2, the toner removed from the surface of the photoreceptor 2 by the cleaning blade 5 falls into the toner receiving portion 38 and is stored. The As the transport coil 31 rotates, the toner in the toner receiver 38 is transported in the direction of arrow A in FIG. The toner conveyed by the conveyance coil 31 is carried in from the inlet 41 of the case 102 shown in FIG. 4 and is delivered to the conveyance belt 32 at the terminal end of the conveyance coil 31. As the conveyor belt 32 runs around, the toner is conveyed in the direction of arrow B in FIG. Then, the toner falls at an opening 39 a provided in the upper portion of the annular path 39, and the toner is transferred to the toner receiving portion 40. Thereafter, the toner in the toner receiver 40 is transported in the direction of arrow C in FIG. 3 by the rotating transport screw 33, and the toner passes through the outlet 42 of the case 102 shown in FIG. Be contained.

  In the configuration of the present invention, the toner conveyance direction (direction of arrow A in FIG. 3) by the conveyance coil 31 and the toner conveyance direction (direction of arrow B in FIG. 3) by the conveyance belt 32 intersect (or are orthogonal to) each other. Yes. Two powder conveyance paths (toner receiving portion 38 and annular path 39) connected in such a position where the toner conveyance direction changes from a certain direction to a direction intersecting (or orthogonal) with it, that is, a direction intersecting each other. In the vicinity of the connecting portion between the two), toner is liable to stay. Therefore, in the present invention, as shown in FIG. 3, a stirring member 37 that stirs the toner is disposed in a toner transfer portion (powder transfer portion) D that transfers toner from the transfer coil 31 to the transfer belt 32. .

  As shown in FIG. 5, the stirring member 37 has a rotating part 43 that rotates, and a plurality of convex parts 44 that are disposed on the outer periphery of the rotating part 43. In this case, the plurality of convex portions 44 are arranged at a predetermined pitch in the circumferential direction of the rotating portion 43. The rotation unit 43 is attached to a support member 35 that supports the conveyance belt 32, and the rotation unit 43 is configured to rotate integrally with the support member 35. That is, the stirring member 37 shares the drive unit with the conveying belt 32 and the like, and has a configuration in which the number of parts is reduced. In addition, the transfer coil 31 is attached to the side opposite to the side attached to the support member 35 of the rotating portion 43. Therefore, as the rotating unit 43 rotates, the transport coil 31 also rotates integrally. The stirring member 37 is not limited to the case where the stirring member 37 is configured integrally with the support member 35 of the transport belt 32. For example, the stirring member 37 can be disposed on the outer peripheral side of the conveyor belt 32.

  FIG. 6 is an enlarged view of the stirring member 37. In FIG. 6, an arrow E is the toner transport direction (powder transport direction). That is, the left side of the figure is the upstream side in the toner conveyance direction E, and the right side of the figure is the downstream side in the toner conveyance direction E. The rotating portion 43 of the stirring member 37 is rotatable in the direction of arrow F around an axis M that is parallel to the toner transport direction E.

  In FIG. 6, a surface 44 a that faces the front in the rotation direction F of each convex portion 44 is configured as a toner feeding surface (powder feeding surface) that feeds toner downstream in the toner transport direction E. That is, the stirring member 37 has both a toner stirring function and a toner transport function. Specifically, the toner feeding surface 44a of the convex portion 44 is disposed to be inclined with respect to the toner conveying direction E so as to face the downstream side. Further, in order to satisfactorily exert the toner stirring function and the toner transport function, the inclination angle θ1 of the toner feed surface 44a with respect to the toner transport direction E is preferably set to 5 ° or more and 30 ° or less.

  Further, the area of the end surface 44b on the downstream side in the toner conveying direction E of the convex portion 44 (hereinafter referred to as the downstream end surface 44b) is the end surface 44c on the upstream side in the toner conveying direction E of the convex portion 44 (hereinafter referred to as the upstream end surface 44c). It is made larger than the area. In this embodiment, the height H1 of the downstream end surface 44b of the convex portion 44 is set to be greater than the height H2 of the upstream end surface 44c. Thus, by setting the height and area of each of the downstream end surface 44b and the upstream end surface 44c of the convex portion 44, the toner is prevented from moving (reversely flowing) in the direction opposite to the toner transport direction E. . In addition, the width of the downstream end surface 44b of the convex portion 44 may be made larger than the width of the upstream end surface 44c to suppress the back flow of the toner.

  Further, the outer diameter surface 44 d of each convex portion 44 is disposed so as to be inclined by an angle θ2 with respect to a straight line N parallel to the axis M of the rotating portion 43. That is, the outer diameter surface 44d is formed in a tapered shape from the upstream end surface 44c to the downstream end surface 44b. As described above, the outer diameter surface 44d is tapered, so that a decrease in toner transportability due to the interference of the toner with the outer diameter surface 44d of the convex portion 44 is suppressed.

  As shown in FIG. 6, the maximum outer diameter portion 44 e of each convex portion 44 is made to be larger than the maximum outer diameter portion 31 e of the transfer coil 31 by a dimension G in the radial direction. As a result, the region in which the toner can be stirred by the stirring member 37 can be made larger than the region in which the toner can be transported by the transport coil 31, and the toner can be sufficiently stirred.

  In the embodiment of the present invention, the rotating portion 43 and the convex portion 44 are integrally formed. The rotating portion 43 and the plurality of convex portions 44 may be configured as separate members, and the stirring member 37 may be manufactured by fixing them by adhesion or the like. However, if the fixing process is insufficient, the convex portions 44 and the like If these parts are lost or if adhesive residue or the like is generated, there is a possibility that the toner transportability may decrease due to the adhesive residue or the like. For this reason, it is desirable that the rotating portion 43 and the convex portion 44 be integrally formed in order to prevent a drop in the toner conveyance performance due to a defect in the above-described components or an adhesive residue. In addition, various materials can be applied as the material of the rotating portion 43 and the convex portion 44. By applying a resin material as the material, it is possible to make the material less susceptible to corrosion.

  FIG. 7 shows another embodiment of the stirring member 37. The agitating member 37 shown in FIG. 7 is disposed in the toner delivery part D that delivers toner from the transport coil 31 to the transport belt 32 in the same manner as described above. The agitating member 37 has a rotating portion 43 and two convex portions 44 that are integrally attached to the outer peripheral surface of the rotating portion 43, and the rotating portion 43 is configured integrally with a support member 35 that supports the conveyance belt 32. Yes. A surface 44 a facing the front in the rotation direction F of the rotation portion 43 in the convex portion 44 shown in FIG. 7 is disposed so as to be orthogonal to the rotation direction F. On the other hand, a surface 44f facing the rear in the rotation direction F of the rotating portion 43 in the convex portion 44 is formed as a curved surface having an arcuate cross section. In this embodiment, the end surface 44b on the downstream side in the toner transport direction E of the convex portion 44 and the end surface 44c on the upstream side in the toner transport direction E of the convex portion 44 are formed in the same shape.

  Note that the configuration of the stirring member 37 is not limited to the above-described embodiment, and it is needless to say that various changes can be made without departing from the gist of the present invention.

  As described above, the stirrer 37 is provided in the toner transfer portion D between the transfer coil 31 and the transfer belt 32, so that the toner can be prevented from staying in the toner transfer portion D. . Specifically, when the toner is transported by the transport coil 31, the transport belt 32, and the like, the stirring member 37 rotates, whereby the toner is stirred by the plurality of convex portions 44. Therefore, the toner does not stay in the toner delivery portion D. Smoothly transported.

  As described above, according to the present invention, it is possible to prevent the toner from staying in the toner delivery part D, and thus it is possible to prevent clogging (blocking phenomenon) of the toner in the conveyance path. Further, the toner transportability can be maintained well and stably. Further, by preventing the toner from staying, it is possible to prevent the toner from leaking from the case forming the conveyance path. In addition, since the conveyance member can be prevented from being pressed by the staying toner, it is possible to prevent a decrease in the conveyance function due to the bending of the conveyance member, breakage of the conveyance member, or the like.

  Further, since the convex portion 44 has the toner feeding surface 44a (see FIG. 6) inclined with respect to the toner conveyance direction E, the toner can be conveyed while stirring, and the toner stays in the toner delivery portion D. It becomes possible to prevent more effectively.

  In addition, by setting the toner conveyance amount (per unit time) by the conveyance coil 31 to be smaller than the toner conveyance amount (per unit time) by the conveyance belt 32, toner retention in the toner delivery unit D can be effectively performed. Can be prevented. Specifically, by setting the pitch of the spirally formed portion of the transport coil 31 to be longer than the pitch of the irregularities on the outer peripheral surface of the transport belt 32, the toner transport amount by the transport coil 31 is changed to the toner by the transport belt 32. It can be set smaller than the transport amount.

  In the embodiment of the present invention, the transport coil 31 is the first toner transport unit (first powder transport unit), and the transport belt 32 is the second toner transport unit (second powder transport unit). In the toner delivery part D between the conveying means and the second toner conveying means, a stirring member 37 is provided. However, the present invention is not limited to this embodiment. For example, the first toner conveying means and the second toner conveying means can be arbitrarily selected from the above-described conveying coil 31, conveying belt 32, conveying screw 33, or other toner conveying means. Therefore, the agitating member 37 may be disposed in the toner delivery section I between the conveyance belt 32 and the conveyance screw 33 in FIG.

  In the above-described embodiment, the case where the configuration of the present invention is applied to a toner transport device that transports toner is taken as an example. However, the configuration of the present invention is also applied to a powder transport device that transports powder other than toner. Applicable.

1 is a schematic configuration diagram of an image forming apparatus of the present invention. FIG. 2 is a schematic configuration diagram of a process unit provided in the image forming apparatus. It is a perspective view of the process unit. It is a perspective view of the process unit. It is a perspective view which expands and shows the principal part of the said process unit. It is an enlarged view of the stirring member arrange | positioned at the said process unit. It is a perspective view which shows other embodiment of the said stirring member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Process unit 31 Conveying coil 31e Maximum outer diameter part 32 Conveying belt 35 Support member 36 Support member 37 Stirring member 43 Rotating part 44 Convex part 44a Toner feeding surface 44b Downstream end surface 44c Upstream end surface 44e Maximum outer diameter part D Toner delivery part E Toner Transport direction F Rotation direction

Claims (16)

A first powder conveying means for conveying the powder in one direction, and a powder delivered from the first powder conveying means to cross the powder conveying direction of the first powder conveying means. In the powder conveying apparatus provided with the second powder conveying means for conveying
An apparatus for conveying powder, characterized in that an agitating member for agitating the powder is disposed in a powder delivery section for delivering powder from the first powder conveying means to the second powder conveying means.   The powder conveying apparatus according to claim 1, wherein the stirring member has a rotating part that rotates and a plurality of convex parts that are disposed on an outer periphery of the rotating part.   The rotating part is configured to be rotatable around an axis parallel to the powder conveying direction, and a surface of the convex part that faces forward in the rotating direction of the rotating part faces downstream of the powder conveying direction. The powder conveying apparatus according to claim 2, wherein the powder feeding surface is configured to be inclined as described above.   The powder conveying apparatus according to claim 3, wherein an inclination angle of the powder feeding surface with respect to a powder conveying direction is set to 5 ° or more and 30 ° or less.   The powder conveyance device according to any one of claims 2 to 4, wherein an area of an end surface of the convex portion on the downstream side in the powder conveyance direction is larger than an area of an end surface of the convex portion on the upstream side in the powder conveyance direction. .   The powder conveyance device according to claim 5, wherein the height of the end surface of the convex portion on the downstream side in the powder conveyance direction is higher than the height of the end surface on the upstream side of the convex portion in the powder conveyance direction.   At least one of the first powder conveying means and the second powder conveying means is an endless conveying belt stretched by a plurality of rotatable support members, and the rotating portion of the stirring member is The powder conveying apparatus according to any one of claims 2 to 6, wherein the powder conveying apparatus is attached to one of the support members and configured so that the rotating portion rotates integrally with the support member.   The powder conveying apparatus according to any one of claims 2 to 7, wherein the rotating portion and the convex portion are integrally formed.   The powder conveying apparatus according to any one of claims 2 to 8, wherein the rotating part and the convex part are made of resin.   A conveying member formed in a spiral shape for conveying the powder in the axial direction while the first powder conveying means rotates, wherein a maximum outer diameter portion of the convex portion of the stirring member is set to a maximum of the conveying member. The powder conveying apparatus according to any one of claims 2 to 9, wherein the powder conveying apparatus is larger in the radial direction than the outer diameter portion.   The first powder conveying means and the second powder conveying means are respectively a conveying member formed in a spiral shape or a conveying belt having a plurality of irregularities formed on the outer peripheral surface, and the first powder conveying means The pitch of the spirally formed part or the unevenness of the means is longer than the spirally formed part of the second powder conveying means or the unevenness pitch. The powder conveying apparatus as described in the item.   12. The powder conveyance according to claim 1, wherein the first powder conveyance unit and the second powder conveyance unit are configured to convey powder by being driven by the same driving unit. apparatus.   The powder conveyance device according to claim 1, wherein the powder is toner. In the process unit configured to be detachable from the image forming apparatus main body,
A process unit comprising the powder conveyance device according to any one of claims 1 to 13.   An image forming apparatus comprising the process unit according to claim 14.   The image forming apparatus according to claim 15, comprising a plurality of the process units.

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