JP2018116174A - Developer conveyance device and development device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer conveyance device and a development device that contribute to a high quality image by sufficiently hindering agglomeration of developer to be supplied.SOLUTION: A developer conveyance device comprising a developer conveyance member rotatable around a rotating shaft and configured to convey developer with the developer conveyance member from a first position where the developer is supplied to a second position in the axial direction of the rotating shaft and inside an internal wall, comprises: a first member located in a position corresponding to the first position in the axial direction and extending in a radial direction from the rotating shaft as viewed from the axial direction; and a second member provided as a weight on an end side of the first member in the radial direction.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a developer conveying device and a developing device, and is suitable for an image forming apparatus such as a laser beam printer (LBP), a digital copying machine, or a multifunction printer.

  Conventionally, in an image forming apparatus using an electrophotographic method, an electrostatic latent image formed on a photosensitive drum is visualized as a toner image using, for example, toner of a two-component developer and visualized using a developing device. The transferred toner image is transferred to the recording material. The toner consumed in the developing device is replenished so as to maintain the weight ratio between the toner of the two-component developer and the magnetic carrier.

  Here, due to factors such as being stored in a high temperature environment for a long period of time or being subjected to slight vibration due to transportation, toners may partially aggregate to form an aggregate of developer for replenishment. When image formation is performed using a developer having a large aggregate size, loading of the developer on the developer carrying member is hindered. Further, when the size of the aggregate is small, the image is crushed or developed as it is in the gap between the developer carrying member and the photosensitive drum, and an image such as a dark streak or dots appears, and the quality of the output image is deteriorated.

  In Patent Document 1, in order to suppress agglomeration of a replenishing developer, a stirring blade is provided in the developing device, and the developer in the developing device and the replenishing developer are rapidly stirred and mixed. It is described that the agglomerates are destroyed by rubbing between the inner wall and the stirring blade.

JP 2014-160163 A

  However, in the configuration in which the agglomerates are destroyed while rubbing the developer container inner wall and the replenishment developer as in Patent Document 1, the developer that has not aggregated is reversed by the heat and shearing force generated by friction. There is a risk of aggregation.

  An object of the present invention is to provide a developer conveying device and a developing device that sufficiently suppress the aggregation of a replenishing developer and contribute to a high-quality image.

  In order to achieve the above object, a developer transport device according to the present invention includes a developer transport member that can rotate around a rotation shaft, and the first position where the developer is replenished in the axial direction of the rotation shaft. A developer conveying device that conveys the developer inside an inner wall with the developer conveying member to a second position, wherein the developer conveying device is located at a position corresponding to the first position in the axial direction, from the axial direction. It has a first member extending in the radial direction from the rotating shaft as viewed, and a second member provided as a weight on the end side in the radial direction of the first member.

  In addition, a developing device according to the present invention includes the developer conveying device.

  According to the present invention, it is possible to provide a developer conveying device and a developing device that contribute to a high-quality image by sufficiently suppressing aggregation of a replenishing developer.

1 is a schematic cross-sectional view illustrating an overall configuration of an image forming apparatus using a developer conveying device according to an embodiment of the present invention. 1 is a schematic cross-sectional view of an image forming unit including a developing device using a developer conveying device according to an embodiment of the present invention. Longitudinal sectional view of a developing device using a developer conveying device according to an embodiment of the present invention Schematic cross-sectional view showing the path from the container for replenishment developer to the developing device Schematic explanatory diagram showing the configuration of the first and second embodiments Explanatory drawing which shows the effect of 1st Embodiment Explanatory drawing which shows the effect of 2nd Embodiment Schematic explanatory drawing showing the configuration of the third embodiment Explanatory drawing which shows the effect of 3rd Embodiment

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

<< First Embodiment >>
(Overall configuration of image forming apparatus)
First, the overall configuration of an image forming apparatus using a developer supply device according to an embodiment of the present invention will be described. FIG. 1 is an overall schematic diagram of an electrophotographic image forming apparatus, and FIG. 2 is a schematic configuration of an image forming unit. The image forming apparatus shown in FIG. 1 is in accordance with image information from a document reading apparatus connected to the image forming apparatus main body (apparatus main body) 100 or a host device such as a personal computer (PC) connected to the apparatus main body 100 so as to be communicable. Then, an image is formed on the recording material. For example, four-color full-color images of yellow (Y), magenta (M), cyan (C), and black (K) are recorded on a recording sheet, a plastic sheet, a cloth, etc. using an electrophotographic image forming means described later. Formed on recording material.

  The image forming apparatus shown in FIG. 1 is a quadruple tandem type, and first, second, third, and fourth image forming units that respectively form yellow, magenta, cyan, and black images as a plurality of image forming units. Part PY, PM, PC, PK. Then, while the intermediate transfer belt 51 (FIG. 2) serving as an intermediate transfer member included in the transfer device 5 moves in the direction of the arrow in FIG. 2 and passes through the image forming units PY to PK, each of the intermediate transfer belts 51 is placed on the intermediate transfer belt 51. In the image forming units PY to PK, images of respective colors are superimposed. A recorded image is obtained by transferring the multiple toner images superimposed on the intermediate transfer belt 51 onto a recording material.

  The configurations of the image forming units PY, PM, PC, and PK are substantially the same except that the development colors are different. Hereinafter, when it is not particularly necessary to distinguish, the subscripts Y, M, C, and K given to the reference numerals to indicate that they belong to any of the image forming units PY to PK are omitted, and the image forming unit P is omitted. The overall explanation is as follows.

  The image forming unit P includes a photosensitive drum 1 formed of a drum-shaped photosensitive member as an electrostatic latent image carrier that carries an electrostatic latent image according to image information. On the outer periphery of the photosensitive drum 1, a charging roller 2 serving as a charging device, an exposure device 3 including a laser exposure optical system, a developing device 4, a transfer device 5, and a cleaning device 7 are provided. Reference numeral 8 denotes a toner cartridge (toner bottle) as a replenishment developer container (replenishment container), which will be further described later with reference to FIG.

  The intermediate transfer belt 51 is wound around a plurality of rollers and rotates in the direction of the arrow in FIG. A primary transfer member is disposed at a position facing each photosensitive drum 1 via the intermediate transfer belt 51. A secondary transfer member is provided at a position facing one of the rollers around which the intermediate transfer belt 51 is wound.

(Operation of image forming apparatus)
At the time of image formation, first, the surface of the rotating photosensitive drum 1 is uniformly charged by the charging roller 2. Next, an electrostatic latent image is formed on the photosensitive drum 1 by scanning and exposing the surface of the charged photosensitive drum 1 according to an image information signal by the exposure device 3. The electrostatic latent image formed on the photosensitive drum 1 is visualized as a toner image by the developer toner using the developing device 4.

  The toner image formed on the photosensitive drum 1 is transferred onto the intermediate transfer belt 51 by the action of the primary transfer bias voltage applied to the primary transfer member at the primary transfer nip where the intermediate transfer belt 51 and the photosensitive drum 1 abut. Primary transcription. For example, when a four-color full-color image is formed, a toner image is transferred from each photosensitive drum 1 onto the intermediate transfer belt 51 sequentially from the image forming unit PY, and the four-color toner images are superimposed on the intermediate transfer belt 51. A multiple toner image is formed.

  On the other hand, the recording material stored in the feeding cassette 9 is moved onto the intermediate transfer belt 51 by a pickup roller, a conveyance roller, a registration roller, and the like at a secondary transfer nip where the intermediate transfer belt 51 and the secondary transfer member abut. The toner image is conveyed in synchronization. The multiple toner images on the intermediate transfer belt 51 are transferred onto the recording material by the action of the secondary transfer bias voltage applied to the secondary transfer member at the secondary transfer nip portion.

  Thereafter, the recording material separated from the intermediate transfer belt 51 is conveyed to the fixing device 6. The toner image transferred onto the recording material is melted and mixed by being heated and pressed by the fixing device 6 and is fixed onto the recording material. Thereafter, the recording material is discharged out of the apparatus.

  Deposits such as toner remaining on the photosensitive drum 1 after the primary transfer process are collected by the cleaning device 7. Thereby, the photosensitive drum 1 is prepared for the next image forming process. Further, deposits such as toner remaining on the intermediate transfer belt 51 after the secondary transfer process are removed by an intermediate transfer body cleaner.

  Note that the image forming apparatus 100 in FIG. 1 may form a single-color or multi-color image using an image forming unit for a desired single color or some of four colors, such as a black single-color image. Is possible.

(Developer)
Next, the configuration of the developing device 4 will be described with reference to FIGS. 2 and 3. In this embodiment, a two-component developer including non-magnetic toner particles (hereinafter referred to as “toner”) and magnetic carrier particles (hereinafter referred to as “magnetic carrier”) is used as the developer. The developing device 4 includes a developing container 41 that stores the two-component developer. In a color image forming apparatus, a two-component developer is widely used because the toner does not need to contain a magnetic material, and the color tone is good.

  The developing container 41 is provided with a developing sleeve 44 as a developer carrying member at a position facing the photosensitive drum 1, and a magnet roll 44 a made up of a magnet as magnetic field generating means that is fixedly disposed in the developing sleeve 44. . Further, a developing blade 42 that forms a thin layer of developer on the surface of the developing sleeve 44, and screw members 41d and 41e that stir and convey the developer in the developing container 41 are disposed.

  The inside of the developing container 41 is divided into a developing chamber 41a and a stirring chamber 41b by a partition wall 41c extending in the vertical direction. A screw member 41d is disposed in the developing chamber 41a, and a screw member 41e is disposed in the stirring chamber 41b. At both ends in the longitudinal direction of the partition wall 41c (left end side and right end side in FIG. 3), delivery portions 41f and 41g (FIG. 3) that allow the developer to pass between the developing chamber 41a and the stirring chamber 41b are provided. ing.

  In the present embodiment, each of the screw members 41d and 41e is formed by providing a spiral blade as a transport unit around the axis (rotation axis) of the magnetic body. In addition to the spiral blades, the screw member 41e is provided with stirring ribs that protrude in the radial direction from the shaft and have a predetermined width in the developer transport direction. The stirring rib stirs the developer as the shaft rotates.

  The screw member 41d stirs and conveys the developer in the developing chamber 41a. The screw member 41e equalizes the toner density under automatic toner replenishment control (hereinafter referred to as “ATR: Automatic Toner Replenisher” control). That is, the toner supplied through the toner replenishing port 43 (FIGS. 3 and 4) and the developer already composed of the toner and the magnetic carrier in the stirring chamber 41b are stirred and transported to uniformize the toner concentration. .

  The screw members 41 d and 41 e are arranged substantially parallel along the rotation axis direction of the developing sleeve 44. The screw member 41 d and the screw member 41 e transport the developer in the opposite directions along the rotation axis direction of the developing sleeve 44. Thus, the developer circulates in the developing container 41 through the delivery portions 41f and 41g by the screw members 41d and 41e. That is, the developer in the developing chamber 41a in which the toner is consumed in the developing process due to the conveying force of the screw members 41d and 41e and the toner density is reduced is transferred to the stirring chamber via one delivery portion 41f (left side in FIG. 3). Move into 41b.

  The toner replenishing port 43 (FIGS. 3 and 4) described above is provided in the uppermost stream portion of the agitating chamber 41b, and is a discharge port of the toner bottle 8 (FIGS. 1 and 4) serving as a replenishing container for storing replenishing toner. A toner hopper 47 is provided as a developer storage unit in a supply path between the toner supply port 43 and the toner supply port 43. The operation of the toner bottle 8 is controlled by the above ATR control according to the image ratio at the time of image formation, the inductance sensor as the toner density sensor, and the density detection result of the patch image by the patch image density detection sensor, and the toner is stirred. Replenish the most upstream part of 41b.

  Then, the developer in the stirring chamber 41b that has been supplied with toner and stirred is moved to the developing chamber 41a through the other delivery portion 41g (right side in FIG. 3). Further, the developing chamber 41a of the developing device 4 is opened at a position corresponding to the developing area facing the photosensitive drum 1, and the developing sleeve 44 is partially exposed to the opening 41j of the developing container 41. It is arranged so that it can rotate. In the present embodiment, the developing sleeve 44 is made of a nonmagnetic material and rotates in the direction of the arrow in FIG. 2 during a developing operation. A magnet roll 44a (FIG. 2) having a plurality of magnetic poles is fixed inside the developing sleeve 44 along the circumferential direction as a magnetic field generating means.

  The two-component developer that is agitated and conveyed by the screw members 41d and 41e and in which the toner adheres to the surface of the magnetic carrier due to frictional charging is attracted to the surface of the developing sleeve 44 by the magnetic field generated by the magnet roll 44a. Form a pool.

  Then, the developer passes through the developer pool by the rotation of the developing sleeve 44, the film thickness is regulated by the developing blade 42, and the portion facing the photosensitive drum 1 in a state where the surface of the developing sleeve 44 is thinly coated. It is conveyed to. In this facing portion, the developer forms chain-shaped magnetic spikes by the magnetic field generated by the magnet roll 44a. In this embodiment, the magnetic spike contacts the photosensitive drum 1, and only the toner is transferred to the electrostatic latent image formed on the surface of the photosensitive drum 1 by the developing bias voltage applied to the developing sleeve 44. A toner image corresponding to the electrostatic latent image is formed on the surface of 1.

  Further, in order to improve the developing efficiency, that is, the application rate of toner to the latent image, a developing bias voltage in which a DC voltage and an AC voltage are superimposed is usually applied to the developing sleeve 44. The developer on the developing sleeve 44 after supplying the toner to the photosensitive drum 1 returns to the developing chamber 41a when the developing sleeve 44 further rotates.

  As described above, in this embodiment, in the developing device 4 using the two-component developer used in the electrophotographic image forming apparatus, the toner and magnetic carrier of the two-component developer contained in the developing device 4 And are triboelectrically charged. Thereafter, the developer is supplied to the photosensitive drum 1 by the developing sleeve 44 to develop the electrostatic latent image on the photosensitive drum 1.

  Further, the toner consumed in the developing device 4 is replenished as follows. That is, a necessary amount of toner is replenished from the toner bottle 8 through the toner hopper 47 so as to maintain T / D (toner / carrier weight ratio) which is a ratio of the toner and the magnetic carrier in the two-component developer. .

(Developer replenishment configuration including developer transport device)
Hereinafter, the replenishment configuration of the developing seat including the developer conveying device according to the present embodiment will be described with reference to FIG. In the present embodiment, the screw member 41e functions as a constituent member of a developer conveying device that conveys the developer inside the inner wall from the first position where the developer is replenished to the second position in the axial direction of the rotation shaft. To do.

  The toner replenishing port 43 corresponding to the first position where the developer is replenished is provided at the upstream end of the screw member 41e in the developing device and at a position away from the developer circulation path. The position is almost nonexistent. However, there is no problem even if the replenishment position is in the developer circulation path, but it is desirable that the toner ratio in the developer is large at a relatively replenishment position.

  In the image forming apparatus 100, the toner bottle 8 is provided above the developing device 41 in the vertical direction. The toner bottle 8 has a discharge port in the depth direction of the image forming apparatus 100, and the toner is transported in the direction of the discharge port along the spiral protrusion inside by rotating the main body of the toner bottle 8. In a region close to the discharge port, the replenishment developer is transported to the discharge port by being gradually measured by the ladder-shaped transport member. Then, the replenishment developer that has reached the discharge port is discharged. The replenishment developer may contain carrier particles.

  The replenishing toner discharged from the toner bottle 8 is temporarily stored in the hopper 47 before reaching the developing device 4. The hopper 47 detects the amount of developer for replenishment inside the hopper 47 by disposing the piezo sensor 47b at a predetermined height. If it is detected from the detection result that the toner bottle is insufficient, the toner bottle 8 is rotated and the toner is supplied into the hopper 47. A replenishment conveyance screw 47a for conveying the toner into the developing device 4 is provided below the hopper 47, and the toner can be quantitatively supplied for every one pitch of the screw.

  When the toner bottle 8 passes through the toner conveyance path from the toner bottle 8 to the toner supply port 43, or when the toner bottle 8 is transported or stored, the temperature and humidity environment may change or the toner may aggregate due to vibration. is there. When the agglomerated toner enters the developing device 4, some agglomerated toner is agitated and destroyed by the developer agitating and conveying member in the developer conveying path, but the agglomerated toner that has not been destroyed is separated from the developing sleeve 44 and the developing blade. The gap formed by 42 is reached.

  Large agglomerated toner clogs the gap and inhibits the coating on the developing sleeve 44 to generate a white streak image. The small agglomerated toner passes through the gap and is developed as a lump in the development nip to become a black spot image, and when it is developed while being crushed, a dark streak image is generated. Factors that cause this aggregation toner include an increase in adhesion of the toner surface due to electrostatic aggregation due to micro-vibration and improvement in low-temperature fixability due to recent energy saving demands.

  In this embodiment, a configuration is proposed in which the aggregated toner is effectively destroyed before reaching the developer circulation path. Conventionally, as a configuration for destroying the aggregated toner, a flexible plastic material mylar or the like is installed on the rotation shaft of the developer conveying member at the position of the toner supply port 43 so that the aggregated toner is placed between the mylar and the container. There is a configuration (second configuration to be described later) that is rubbed and destroyed. However, in this configuration, there is a possibility that small agglomerated toner may be produced by friction by rubbing the toner that has not been agglomerated.

  In this embodiment, a configuration is provided for destroying (suppressing) the aggregated toner supplied from the replenishment upstream side of the developing device 4 without creating new aggregated toner by rubbing as described above. In other words, a configuration in which the friction against the toner in the vicinity of the toner replenishing port 43 of the developing device 4 is minimized and a configuration for suppressing the aggregated toner is provided. Specifically, as shown in FIG. 5, the collision member 48 includes a stirring member 48a that is a first member and a weight member 48b that is a second member.

  More specifically, silicon as a belt-like member (plate-like member) that is a stirring member 48a is located at a position corresponding to the toner replenishing port 43 in the axial direction, and is on the rotating shaft of a screw member 41e as a developer conveying member. One end of the sheet (elastic member) is installed. And the elliptical weight member 48b which is the same lump (elastic member) of the same silicon | silicone is installed in the edge part side (more preferably the edge part most distant from the rotation axis) of the stirring part agent 48a. . That is, the stirring member 48 has one end in the radial direction as viewed from the axial direction of the screw member 41e on the rotating shaft of the screw member 41e and a weight member 48b on the other end side.

  The stirrer 48a is preferably made of a material having some elasticity like the above-described silicon sheet, and the weight member 48b is also preferably a member having elasticity on the surface so as not to be damaged by collision. The total length formed by the stirring member 48a and the weight member 48b is longer than the distance from the rotation axis of the screw member 41e to the container wall (inner wall) when viewed from the axial direction of the screw member 41e. A silicon sheet is configured to bend with elasticity.

  As the screw member 41e rotates, the silicon sheet as the stirring member 48a and the weight member 48b rotate and repeat the behavior of colliding with the container wall and repelling and separating. At this time, the rebounding method changes depending on the angle hitting the container wall and the amount of toner, and the container wall collides with the random position and timing.

  As a result, when the replenishment toner transported from the replenishment transport screw 47a provided below the toner hopper 47 shown in FIG. Is suppressed. That is, the agglomeration is suppressed by the collision energy between the weight member 48b rotating together with the screw member 41e, the container wall, the rotating shaft, and the stirring blade.

  A comparison was made of how many image defects caused by the aggregated toner occur between the configuration of the present embodiment and the conventional configuration. In detail, it compared as follows. First, 10 g of the replenishing toner was left for 1 week in an environment of 45 ° C. and 80% temperature and humidity, and then left overnight at 23 ° C. and 45% of normal temperature and humidity to prepare a replenishing toner containing a large amount of agglomerated toner. This is a toner for comparing the capability of destroying (suppressing) the agglomerated toner between the configuration of the present embodiment and the conventional configuration, and cannot occur at the time of image formation in the actual market.

  Then, a developing device 4 filled with a developer was prepared, and development, charging, transfer high pressure, exposure laser light amount, and the like were set for image formation so that proper image formation was possible. Therefore, 10 g of the replenishing toner containing the agglomerated toner was uniformly mixed with 90 g of normal toner and filled in the hopper 47. Then, a dummy developing device was installed in the image forming apparatus 100, and a replenishment operation was performed in advance to fill the replenishment conveying screw 47a (FIG. 4) with replenishment toner. Then, the developing device 4 for image formation was installed in the main body of the image forming apparatus 100 to perform image formation. The images were A4 paper, 60 hex full-scale halftone images, and 10 sheets were printed at a speed of 60 cpm.

  When the replenishment toner including the agglomerated toner is supplied to the developing container 41, it passes from the toner replenishing port 43 through the stirring chamber 41b and the delivery portion 41g (FIG. 3) to the developing sleeve 44 in about 4.0 [sec]. To reach. Therefore, the aggregated toner appears on the image from the third or fourth sheet. At this time, a streak caused by agglomerated toner has a configuration without agglomerate destruction configuration (first configuration), a conventional Mylar rubbing configuration (second configuration), and a configuration of the present embodiment (third configuration). The number of occurrences of images and potty images was compared. FIG. 6 shows a result of comparison of image defect levels in the first to third configurations.

  In the case of the first configuration, when toner is being conveyed by the screw member 41e of the stirring chamber 41b, the agglomerated toner may be destroyed by the stirring blades of the screw. The agglomerated toner remained until 44 was reached. In the case of the second configuration, white streak images caused by large agglomerated toner such as white streaks disappeared, but the amount of reduction in the number of black streak images and black spotted images caused by small agglomerates became small. .

  Here, in the case of the third configuration of the present embodiment, it was confirmed that the number of black streak images and black spotted images was further reduced as compared with the second configuration. Accordingly, it can be seen that the third configuration has a higher ability to destroy (suppress) the aggregated toner than the first and second configurations.

  As described above, in this embodiment, the aggregate can be suppressed with a configuration having a shorter contact time, instead of destroying the aggregate with a configuration in which force is applied to the developer for a long time, such as friction or rubbing. That is, a toner agglomeration destruction member configured to collide with the inner wall of the developing container 41 is installed in the vicinity of the toner supply port 43 of the developing device 4. As a result, even when toner aggregates are generated in the toner bottle 8, it is possible to destroy the toner aggregates enough to affect the image. Thereby, a high quality image can be obtained over a long period of time.

<< Second Embodiment >>
In this embodiment, basically the same apparatus configuration as that of the first embodiment is used, and a configuration for efficiently destroying (suppressing) the aggregated toner by the collision member 48 is provided. The configuration of the present embodiment (fourth configuration) is the same as that of the first embodiment (FIG. 5) on the drawing.

  In the present embodiment, unlike the first embodiment, the specific gravity (density) of the weight member 48b is made of silicon higher than that of the stirring member 48a with respect to the stirring member 48a in the collision member 48. It is desirable that the specific gravity of the weight member 48b is at least 5% greater than that of the stirring member 48a. As a result, the centrifugal force applied to the weight member 48b by the rotation of the screw member 41e increases the force acting in the circumferential direction at a position away from the rotation axis of the screw member 41e in the radial direction.

  In the first embodiment, since the same density silicon is used for the agitating member 48a and the weight member 48b, the weight member 48b that has once repelled and collided with the container wall has a little time lag until it collides with the container wall again. large. On the other hand, in the present embodiment, the weight member 48b that has once collided and repelled easily jumps in the container wall direction by centrifugal force. Therefore, the number of collisions with the container wall of the developing container 41 per unit time increases, and the aggregated toner can be destroyed (suppressed) at a high frequency.

  The weight member 48b may have, for example, a composite configuration in which a material other than silicon having a certain degree of elasticity or a metal having a higher specific gravity than the silicon is included. The surface hardness of the weight member 48b is necessary to destroy the aggregated toner, but if it is too high, foreign matter may be mixed into the developer due to wear or damage of the wall surface of the developing container 41 or the weight member 48b itself. Because there is not suitable. On the other hand, if the surface hardness of the weight member 48b is too low, collision energy for destroying the aggregated toner cannot be obtained, which is not suitable.

  Here, FIG. 7 shows a result of comparison of image defect levels in the first to fourth configurations. In the same manner as in the first embodiment, image formation was performed by supplying aggregated toner. Similarly, when 10 halftone images were formed, the white streak image with a large lump was the same as in the first embodiment, and the amount of black streak image or black spot image was further reduced.

  As described above, according to the present embodiment, the aggregated toner can be further destroyed (suppressed), and a highly stable and high quality image can be obtained.

<< Third Embodiment >>
The present embodiment is based on the same configuration as that of the second embodiment, and further includes a configuration (fifth configuration) for efficiently destroying the aggregated toner. The configuration of this embodiment is shown in FIG. In this embodiment, two sets of the stirring member 48a and the weight member 48b installed in the second embodiment are installed in the vicinity of the toner supply port 43 of the developing device 4 in the axial direction of the screw member 41e. And each collision member 48 was made into the position which shifted the phase by 180 degrees along the spiral stirring blade. Here, being provided in different phases means being provided in different radial directions when viewed from the axial direction of the screw member 41e.

  At this time, it is desirable that the number of collision members 48 to be installed is two or more (provided a plurality), but if adjacent collision members 48 are too close to each other, there is a possibility that the respective stirring members 48a and weight members 48b may be caught. .

  When a plurality of collision members 48 are arranged across the spiral stirring blades, the distance and phase between the collision members need not be considered. However, when the plurality of collision members 48 are arranged without straddling the spiral stirring blades, the phase is 45 ° or more, or the longitudinal distance (axial direction) of the rotation shaft is set to 1. of the length of the stirring member 48a. It is desirable to separate 5 times or more.

  By using the above-described configuration, the aggregated toner in the replenishment developer can be destroyed (suppressed) at a high frequency before reaching the developer circulation path.

  Here, FIG. 9 shows a result of comparison of image defect levels in the first to fifth configurations. In the same way as in the first and second embodiments, image formation was performed by supplying aggregated toner. Similarly, when 10 halftone images were formed, the white streak image with a large block was the same as in the second embodiment, and the amount of black streak images and black spotted images was further reduced.

  As described above, by using the configuration of the present embodiment, the aggregated toner can be further broken, and a more stable and high-quality image can be obtained. Further, the M / S distribution on the developing sleeve 44 can be stably formed, and a high-quality developing device can be provided.

(Modification)
As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

(Modification 1)
In the above-described embodiment, the toner hopper 47 and the replenishment conveying screw 47a are provided between the toner bottle 8 and the developing device 4, but the present invention is not limited to this. A configuration in which only the replenishment conveyance screw 47a without the toner hopper 47 or a configuration in which the toner hopper 47 and the replenishment conveyance screw 47a are not provided and the toner is directly supplied from the toner bottle 8 to the toner replenishment port 43 is also applicable.

41e ··· Screw member, 43 ·· Toner supply port, 48a · · Stirring member, 48b · · Weight member

Claims (9)

A developer conveying member rotatable around a rotation axis;
A developer conveying device that conveys the developer inside the inner wall by the developer conveying member from a first position where the developer is replenished to a second position in the axial direction of the rotation shaft;
A first member that is in a position corresponding to the first position in the axial direction and extends in a radial direction from the rotating shaft as viewed from the axial direction;
A second member provided as a weight on the end side in the radial direction of the first member;
A developer conveying device comprising:   The developer conveying apparatus according to claim 1, wherein both the first member and the second member are elastic members.   The developer conveying apparatus according to claim 2, wherein the second member has higher hardness and higher specific gravity than the first member.   4. The developer conveying device according to claim 1, wherein a plurality of sets of the first member and the second member are provided in the axial direction. 5.   The developer conveying device according to claim 4, wherein the plurality of sets are provided in different radial directions when viewed from the axial direction.   6. The developer conveying device according to claim 1, wherein a total length formed by the first member and the second member is longer than a distance from the rotation shaft to the inner wall.   The developer conveying device according to claim 1, wherein the developer is a two-component developer including a toner and a magnetic carrier. A storage container for storing a developer for replenishment;
8. The developer conveyance according to claim 1, wherein the developer replenished via a replenishment path from the discharge port of the storage container to the first position is conveyed to the second position. 9. Equipment,
A developer carrying member carrying the developer conveyed by the developer conveying device;
A developing device comprising:   The developing device according to claim 8, further comprising a developer storage unit in the supply path.