JP4022357B2 - Image forming apparatus and image forming apparatus unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus such as a copying machine, a facsimile machine, and a printer. More specifically, the present invention relates to an agent carrier that carries an agent and a conveyance unit that conveys the agent while stirring the agent in the axial direction of the agent carrier. The present invention relates to an image forming apparatus including an agent transporting unit having both ends supported by bearings in a container.
[0002]
[Prior art]
In recent years, there has been a trend toward smaller and faster image forming apparatuses. Accordingly, in the developing device provided in the image forming apparatus, a larger amount of developer is circulated at high speed in the developing container which is a limited space, and the toner is quickly charged to the developer carrying member. Is required to supply.
[0003]
Conventionally, as this type of developing device, for example, a first developer conveying member that conveys toner from a toner container to a developing position that faces a developer carrying member, and a conveying direction of the first developer conveying member There has been proposed a developing device in which a second developer conveying member that conveys toner in a direction opposite to that of the developing device is arranged in parallel. In the proposed developing device, when supplying the developer to the developer carrying member while charging the toner, each of the first and second developer conveying members is disposed around the first developer conveying member. Since the developer is circulated in the formed developer storage space, it is possible to prevent the toner from shifting in the longitudinal direction in the developing device.
[0004]
[Problems to be solved by the invention]
However, when the developer is circulated at high speed in a small space such as a developer container, the developer is located in the vicinity of a bearing portion that supports the developer transport means on the downstream side in the developer transport direction of the developer transport means. The pressure of the developer conveyed by the conveying means is intensely applied. Further, since the developer conveying means rotates at a high speed, frictional heat is generated at the rubbing portion between the developer conveying means and the bearing portion.
[0005]
Usually, a rubber seal member such as a V ring or a G ring or a magnet ring is attached to the bearing portion of the developer conveying means (including the developer agitating means) in order to prevent toner from entering the bearing portion. ing. However, these normally provided seal members and the like cannot resist the pressure of the developer conveyed by the developer conveying means as described above, and the toner enters the bearing and melts and adheres due to frictional heat. There is a fear. Then, the torque of the developer conveying member is increased, and there is a possibility that the developer conveying member may be locked in some cases.
[0006]
Note that the developer pressure rise in the bearing portion of the developer conveying means and the problems associated therewith are not only due to the case where the developer is conveyed toward the bearing portion by the developer conveying means, but, for example, in the axial direction Even the one that conveys the developer around can be caused by the downsizing of the developer storage space. Furthermore, it may occur not only in the developing apparatus but also in a container of a cleaning apparatus that transports a cleaning agent, which often uses a carrier component of the developer, by an agent carrier. Furthermore, the developing device and the cleaning device may be configured as a single unit or a unit with a latent image carrier such as a photosensitive member and detachable from the image forming apparatus main body. When using the image forming apparatus main body, the above problems may occur.
[0007]
The present invention has been made in view of the above-described problems, and the object of the present invention is to prevent toner from entering the bearing portion of the agent conveying member in the container, and to prevent torque increase and locking of the agent conveying member. Another object of the present invention is to provide an image forming apparatus and a unit for the image forming apparatus that can be used.
[0008]
[Means for Solving the Problems]
To achieve the above object, according to the invention of claim 1, agent dosage carrying body stirred you conveyed while agent transport unit in the axial direction of the bearing to carrier, agent agent accommodated in the accommodation section A shaft portion that is rotatably supported by a bearing portion at both ends in the rotation axis direction in the container, and a screw portion that is a conveyance portion that is spirally projected from the shaft portion. In the image forming apparatus included in the means, a small chamber for accommodating the end of the screw portion on the downstream side in the agent conveying direction of the agent conveying means and a partition wall for partitioning the agent accommodating portion are provided in the container, and the shaft A small hole is provided in the partition wall that allows the part to pass through without rubbing, and a reverse transport section that transports the agent in a direction opposite to the screw section is provided at a location between the bearing section and the partition wall in the bearing section. Providing the small hole and the bearing portion to face each other through the space of the small chamber, One, by the partition wall, is characterized in that so as to at least partially restrict the movement of the agent toward the said bearing portion from the screw portion.
[0009]
In this image forming apparatus, the movement of the agent conveyed by the screw portion of the agent conveying means in the agent accommodating portion in the developing container to the bearing portion side is partially restricted by the partition wall before reaching the bearing portion. Is done. Therefore, the pressure of the conveyed agent is not directly applied to the bearing portion. Therefore, it is possible to prevent the agent from entering the bearing portion due to the pressure of the conveyed agent.
[0011]
Further, in this image forming apparatus, the agent conveyed by the screw portion of the agent conveying means in the developing container is pressed against the partition wall before reaching the bearing portion, and the movement to the bearing portion side is restricted. And the space which does not receive the pressure of the conveyed agent directly between a partition wall and a bearing part is made. Therefore, the agent can be prevented from entering the bearing portion due to the pressure of the conveyed agent, and a good sliding state at the bearing portion can be maintained. Since a small hole is formed in the partition wall so as not to rub against the shaft of the agent conveying means, there is no fear that the toner melts and adheres to the small hole due to frictional heat. In this image forming apparatus, the agent movement restricting means for restricting the agent movement can be easily realized at a low cost.
[0013]
Further, in this image forming apparatus, a part of the agent conveyed by the screw portion of the agent conveying means passes through the small hole of the partition wall and enters the space between the partition wall and the bearing portion. The reverse conveying portion provided in the space is conveyed in the direction opposite to the agent conveying direction of the screw portion and is again scraped out from the small hole toward the agent containing portion . Therefore, the agent does not stay in the space between the partition wall and the bearing portion. As a result, the good sliding state of the bearing portion can be maintained more reliably.
[0014]
Further, the invention of claim 2, the image forming apparatus according to claim 1, said inverse transport unit is characterized in being constituted by a screw or spiral grooves.
[0015]
In this image forming apparatus, the agent can be conveyed in the direction opposite to the agent conveying direction by configuring the reverse conveying unit with a screw or a spiral groove.
[0016]
The invention of claim 3 is agent comprises a carrier to carrier, and a stirring you conveyed while agent transport unit in the axial direction of the agent carrier accommodating a dosage in the developer container, and the container The agent conveying means has a shaft portion that is rotatably supported by the bearing portion at both ends in the rotation axis direction, and a screw portion that is a conveying portion that spirally projects from the shaft portion, In the image forming apparatus unit that is detachable from the forming apparatus main body, a small chamber that accommodates an end of the screw portion on the downstream side in the agent conveying direction of the agent conveying means in the container, and the agent accommodating portion A partition wall for partitioning is provided, a small hole is provided in the partition wall for allowing the shaft portion to pass through without rubbing, and a reverse transport portion for transporting the agent in a direction opposite to the screw portion is provided between the bearing portion and the bearing portion in the bearing portion. The small hole and the bearing portion are provided at a location between the partition wall and the small chamber. They are opposed to each other via a space, and by the partition wall, is characterized in that so as to at least partially restrict the movement of the agent toward the said bearing portion from the screw portion.
[0017]
According to a fourth aspect of the present invention, in the image forming apparatus unit of the third aspect , the agent is a developer, and the agent carrier has a developing function.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is applied to an electrophotographic copying machine (hereinafter simply referred to as a copying machine) will be described. FIG. 1 is a schematic configuration diagram of a copying machine according to the present embodiment. As shown in the figure, this copying machine supplies a scanner unit 100 that reads image information of an original, an image forming unit 200 that forms an image on a transfer sheet P as a recording member, and supplies the transfer sheet P to the image forming unit 200. And a sheet feeding unit 300 for performing the above.
[0019]
The scanner unit 100 reads image information of a document placed on a contact glass (not shown) by the light receiving device 101 and sends the read image information to the control unit.
[0020]
Based on the image information received from the scanner unit 100, the control unit controls a laser diode, a polygon mirror, and the like (not shown) disposed in the laser writing unit 201 of the image forming unit 200 to perform the photosensitive unit 202. Laser writing light L is irradiated toward the body drum 1. By this irradiation, an electrostatic latent image is formed on the surface of the photosensitive drum 1, and this latent image is developed into a toner image through a predetermined development process. In addition to the laser writing unit 201 and the photosensitive unit 202, the image forming unit 200 serves as an openable / closable door that can be opened and closed in the direction of the arrow in the drawing centering on the transfer device 203, the fixing device 204, the paper discharge device 205, and the rotation shaft 206. Door 209, door 209 as an opening / closing door that can be opened and closed in the front-rear direction in FIG. The development process will be described later in detail.
[0021]
The paper feed unit 300 includes four paper feed cassettes 301a, b, c, d as four recording member supply devices, four registration rollers 302a, b, c, d, and four paper transport roller pairs 303a, b, c, d. Etc. Each of the four paper feed cassettes 301a, b, c, and d is configured to mount and store the transfer paper P, and is configured to be detachable from the copying machine main body in the front-rear direction in the drawing. Each of the registration rollers 302a, b, c, and d discharges only one sheet of transfer paper P placed on the paper feed cassettes 301a, b, c, and d, and is conveyed by a pair of conveyance rollers 303a, b, c, and d. Send to the configured paper transport path.
[0022]
When the control unit receives the image information from the scanner unit 100, the control unit causes the laser writing as described above or the development process to form a toner image on the photosensitive drum 1, and in accordance with the image information. One of the four registration rollers 302 is operated to feed the transfer paper P having a size. By this operation, one transfer paper P is discharged from one of the four paper feed cassettes 301, passes through the paper transport roller pair 303, and is transported to the transfer position between the photosensitive unit 202 and the transfer device 203. Is done. At this transfer position, a transfer roller to which a transfer bias is applied by a bias applying means (not shown) is in contact with the photosensitive drum 1 to form a nip. The toner image developed on the photosensitive drum 1 is superimposed on the transfer paper P sandwiched between the nips. Then, the image is transferred onto the transfer paper P under the influence of the transfer electric field formed in the nip by the transfer bias and the contact pressure between the photosensitive drum 1 and the transfer roller.
[0023]
The transfer paper P onto which the toner image has been transferred in this manner is sent into the fixing device 204, and the toner image is fixed by the synergistic action of applying pressure and heating between the pressure roller 211 and the heating roller 212. I'm damned. Then, after being discharged from the transfer device 203, it is discharged out of the apparatus via a pair of paper discharge rollers of the paper discharge device 205.
[0024]
Next, the development process in this copying machine will be described in detail. FIG. 2 is a schematic configuration diagram showing a photoconductor unit of the copying machine. As shown in the figure, the photosensitive unit 202 includes a latent image forming unit 2, a developing unit 3 as a developing device, and a cleaning unit 4. The developing unit 3 includes an agent carrying unit 5 having a developing roller 7 as a developer carrying member, and an agent containing unit 6 containing a developer.
[0025]
The latent image forming unit 2 is rotatably mounted with the above-described photosensitive drum 1 serving as a latent image carrier. The photosensitive drum 1 is driven to rotate counterclockwise in the drawing by a drive system (not shown). The Further, the latent image forming unit 2 includes a charging roller 8 as a charging device, a static elimination lamp 9 and the like around the photosensitive drum 1.
[0026]
The surface of the photosensitive drum 1 is first charged by contact with the charging roller 8 after being neutralized by irradiating the neutralizing light from the neutralizing lamp 9 in accordance with the counterclockwise rotation driving in the figure. Next, as described above, the laser writing light L is emitted from the laser writing unit 201. The surface of the photosensitive drum 1 carries an electrostatic latent image by this irradiation. As will be described later, when the electrostatic latent image passes through a position (development position) facing the agent carrier 5 as the photosensitive drum 1 rotates, toner as an image forming substance is attached to the electrostatic latent image. Developed into an image.
[0027]
The agent storage unit 6 includes a storage unit casing 10 as a developer container, a first transport screw 11 and a second transport screw 12 as developer transport members, and a toner concentration sensor 13. An opening portion that opens toward the developing roller 7 of the agent carrying portion 5 is formed in the accommodating portion casing 10, and the second conveying screw 12 is disposed to face the developing roller 7.
[0028]
The toner concentration sensor 13 is a magnetic permeability sensor that magnetically detects the toner concentration (mixing ratio of toner and carrier) of the developer in the developer storage space on the first conveying screw 11 side in the developer in the storage casing 10. The output voltage value is changed according to the toner concentration in the developer.
[0029]
FIG. 3 is a perspective view showing a main part of the agent container 6. The 1st conveyance screw 11 and the 2nd conveyance screw 12 are arrange | positioned so that a mutually parallel positional relationship may be maintained, and are rotationally driven by the drive system which is not shown in figure. As will be described later, the first conveying screw 11 and the second conveying screw 12 are respectively composed of shaft portions 11a and 12a and helical screw portions 11b and 12b as conveying portions for conveying the developer while stirring. Has been.
[0030]
A partition wall 10a configured integrally with the housing casing 10 is provided between the first conveying screw 11 and the second conveying screw 12, and thus includes toner (powder) and magnetic carrier (particles). A developer accommodating space for accommodating a two-component developer (hereinafter referred to as a developer) is individually secured around both. Openings 10b and 10c are formed in the vicinity of both ends of the conveying screw 11 on the partition wall 10a so that two adjacent developer storage spaces on the partition wall 10a communicate with each other.
[0031]
First, toner is introduced into a developer storage space in which the first conveying screw 11 is stored from a toner supply device (not shown) through a first toner receiving port 14 by toner density control. Then, after the toner comes into contact with the developer around the first conveying screw 11, the toner is conveyed in the direction of arrow A while being mixed and stirred with the developer as the first conveying screw 11 rotates. . During the conveyance, the toner is rubbed with the magnetic carrier, the first conveyance screw 11 and the like, and is charged to, for example, a negative polarity. The developer transported to the side surface portion X by the first transport screw 11 is second transported through the opening 10b between the first transport screw 11 and the second transport screw 12, as shown by the arrow B direction. It is delivered to the developer storage space on the screw 12 side. Then, this is conveyed in the direction of arrow C by the rotation of the second conveying screw 12. This conveyance further promotes charging of the toner in the developer.
[0032]
As shown in FIG. 2, the developer in the agent storage unit 6 is carried on the developing roller 7 of the adjacent agent carrying unit 5. The developing roller 7 is composed of, for example, a magnet roller (not shown) having five magnetic poles and a cylindrical nonmagnetic pipe covering the same, and only the nonmagnetic pipe is driven to rotate clockwise in the figure by a driving system (not shown). It has become so. This non-magnetic pipe draws and carries the developer conveyed in the direction of arrow C by the second conveying screw 12 with its rotation by the magnetic force generated by the magnet roller. Thus, in the agent carrying part 5, the developer is carried on the developing roller 7 as the nonmagnetic pipe rotates.
[0033]
The thickness of the developer carried on the developing roller 7 is regulated by a flexible developing doctor 15 that contacts the developing roller 7. The developer on the developing roller 7 whose layer thickness is regulated by the developing doctor 15 is conveyed to a developing position that is a position facing the photosensitive drum 1. A developing bias is applied to the developing roller 7 by a bias applying means (not shown), thereby causing a potential difference between the photosensitive drum 1 and the developing roller 7. A developing electric field is formed between the photosensitive drum 1 and the developing roller 7 by this potential difference.
[0034]
When the developer conveyed to the development position as described above is affected by the development electric field, the electrostatic adhesion state between the toner and the magnetic carrier is released, and the toner is transferred onto the photosensitive drum 1. Adhere to the electrostatic latent image. However, an effective developing electric field does not act between the non-image portion on the photosensitive drum 1 and the developer on the developing roller 7, and toner does not adhere to the non-image portion. Thus, the toner adheres only to the electrostatic latent image, so that the electrostatic latent image is developed.
[0035]
The developing doctor 15 described above regulates the developer layer thickness on the developing roller 7 to stabilize the image density by keeping the amount of the developer conveyed to the developing position constant. It also plays a role of promoting frictional charging of the toner in the developer by applying pressure accompanying regulation.
[0036]
The developer that has passed through the developing position is taken into the agent carrier 5 again as the developing roller 7 rotates, and then contacts the developer around the second conveying screw 12 and is collected in the agent container 6. Is done. The developer collected in this manner and the developer not carried on the developing roller 7 are conveyed to the side surface portion Y by the rotation of the second conveying screw 12. Then, as indicated by the arrow D direction, the developer is returned to the developer storage space on the first conveying screw 11 side through the opening 10c between the first conveying screw 11 and the second conveying screw 12.
[0037]
The developer returned to the developer storage space on the first conveying screw 11 side is in a state in which the toner concentration is lowered than usual because the toner is consumed with the development. Therefore, the control unit detects the toner concentration of the developer stored in the developer storage space on the first conveying screw 11 side based on the output voltage value from the toner concentration sensor 13. Based on the detection result, a necessary amount of toner is supplied from the toner cartridge 210 into the agent container 6 via the first toner receiving port 14 by a toner supply device (not shown), and the developer in the agent container 6 is supplied. The toner density is kept almost constant.
[0038]
The toner image developed on the photosensitive drum 1 is conveyed to a transfer position that is opposed to the transfer roller (see FIG. 1) of the transfer device 203 as the photosensitive drum 1 rotates, and the transfer paper is transferred as described above. Transferred to P. Then, the transfer sheet P electrostatically attached to the photosensitive drum 1 is separated from the photosensitive drum 1 by discharging from the transfer position or by the separation claw 16 and then conveyed to the fixing device 204 described above.
[0039]
The residual toner remaining on the surface of the photosensitive drum 1 after passing through the transfer position is mechanically affected by the cleaning blade 17 when conveyed to a position facing the cleaning unit 4 shown in FIG. Scratched from the surface. Then, after being collected in the casing of the cleaning unit 4 to be collected toner, it is conveyed to the front side in the figure by a discharge screw 18 that is rotationally driven by a drive system (not shown). Here, the discharge screw 18 is driven by a gear (not shown) using the photosensitive drum 1 as a drive source.
[0040]
FIG. 4 is a perspective view showing a schematic configuration of the photoreceptor unit. As shown in FIG. 4, the photosensitive unit 202 includes a collection path 19 as a transport path extending in a diagonal direction from the lower left to the upper right in the drawing. The recovered toner that has fallen from the conveyance path discharge port 18a by the discharge screw 18 is facilitated by the swing of the swing member 20, and falls along the recovery path 19 in the direction of arrow E in the figure. The recovered toner falling along the recovery path 19 is conveyed into the agent storage unit 6 via the second toner receiving port 21 provided in the agent storage unit 6 as indicated by an arrow F direction in FIG. Is done. Then, the developer is returned to the developer storage space on the first conveying screw 11 side and reused for development.
[0041]
As shown in FIG. 2, the photoconductor unit 202 is provided with a seal member 22 between the agent carrying part 5 and the agent containing part 6 in an initial state immediately after shipment from the factory. The communication space between the carrier 5 and the agent container 6 is blocked. The photoconductor unit 202 includes a photoconductor shutter 23 that can be opened and closed. The photoreceptor shutter 23 covers and protects the photoreceptor drum 1 when the photoreceptor unit 202 is detached from the apparatus main body.
[0042]
By the way, as shown in FIG. 3, the developer conveyed in the direction of arrow A by the first conveying screw 11 is pressed against the side surface portion X of the developing casing 10 on the downstream side in the developer conveying direction with a very strong force. Become. Similarly, the developer transported in the direction of arrow C by the second transport screw 12 is pressed against the surface measurement portion Y of the developing casing 10 on the downstream side in the developer transport direction with a very strong force.
[0043]
FIG. 5 is a cross-sectional view illustrating the configuration of the conveyance screw end on the downstream side in the developer conveyance direction. Here, the first conveying screw will be described. As shown in FIG. 5, the first conveying screw 11 has a shaft portion 11 a and a spiral screw portion 11 b as a conveying portion, and both ends of the shaft portion 11 a are installed on side surfaces of the developing casing 10. Each part 24 is rotatably supported. A rubber G-ring 25 is press-fitted into the bearing portion 24 to prevent the developer from entering the sliding portion between the shaft portion 11 a and the bearing portion 24. In addition, about the member provided in the bearing part 24, not only the G ring 25 but all conventionally well-known things, such as a magnet ring, can be used.
[0044]
However, when the developer is circulated at high speed in the developing casing 10, the pressure of the developer conveyed by the screw portion 11 b is intensely applied to the side surface portion X. For this reason, the bearing portion 24 provided on the side surface portion X cannot withstand the pressure of the developer only by the conventionally used G ring 25. As a result, the developer may enter the bearing portion 24 and the toner may be melted and fixed by frictional heat. Therefore, in the present embodiment, the developer movement that partially restricts the movement of the developer toward the bearing portion 24 between the end portion 11c of the screw portion 11b and the bearing portion 24 on the downstream side in the developer transport direction. As a restricting means, a partition wall 26 for partitioning a space between the end portion 11c and the bearing portion 24 is provided.
[0045]
In this partition wall 26, the shaft portion 11a passes, but a small hole 26a is formed so that the shaft portion 11a does not rub. Further, a reverse conveying portion 11d is formed by a spiral groove on the shaft portion 11a between the partition wall 26 and the bearing portion 24. The reverse transport unit 11d transports the developer in the small chamber R, which is a space between the partition wall 26 and the bearing portion 24, in the direction opposite to the developer transport direction.
[0046]
In addition, although the reverse conveyance part 11d demonstrated the 1st conveyance screw 11 which comprises a spiral groove here, for example, a reverse conveyance part may be comprised with a screw and a developer is made into the developer conveyance direction of a conveyance part. Should just be comprised by the shape which can be conveyed in the opposite direction.
[0047]
The developer in the developing casing 10 conveyed by the screw portion 11b of the first conveying screw 11 is conveyed in the direction of arrow A in the drawing by the screw portion 11b as shown in FIG. The developer transported by the screw part 11b is once pressed against the partition wall 26 on the downstream side in the developer transport direction and is restricted from moving to the bearing part side, and as shown by the arrow B direction, It flows to the opening 10b side. Therefore, a space that is not directly affected by the circulation of the developer is formed in the small chamber R between the partition wall 26 and the bearing portion 24. Therefore, the pressure of the developer conveyed by the screw portion 11 b is not directly applied to the bearing portion 24, and the developer can be prevented from entering the bearing portion 24. As a result, it is possible to prevent an increase in torque and a lock due to toner adhering to the bearing portion 24.
[0048]
Further, a part of the developer pressed against the partition wall 26 passes through the small hole 26a and enters the small chamber R as indicated by the arrow G. However, the reverse conveyance provided in the shaft portion 11a in the small chamber R is performed. The portion 11d is scraped out again to the screw portion 11b side as indicated by the arrow H through the small hole 26a of the partition wall 26. Therefore, the developer does not stay in the small chamber R, and the good sliding state can be maintained in the bearing portion 24 more reliably.
[0049]
In this embodiment, the copying machine using a two-component developer composed of toner and a magnetic carrier has been described. However, the present invention can also be applied to an image forming apparatus using a one-component developer composed only of toner. is there.
[0050]
Also, a dry development type copying machine using a two-component developer composed of toner and a magnetic carrier has been described. However, a wet development type image forming apparatus using a liquid developer composed of toner and a liquid carrier is also described in the present invention. Applicable.
[0051]
Further, the copying machine configured to directly transfer the toner image on the photosensitive drum 1 onto the transfer paper P has been described. However, the present invention can also be applied to an image forming apparatus that transfers an image via an intermediate transfer member.
[0052]
Further, although the copying machine including only one developing unit 5 as the developing device has been described, the present invention can also be applied to an image forming apparatus including a plurality of developing devices such as a revolver developing unit.
[0053]
【The invention's effect】
According to the first to fourth aspects of the present invention, the partition that partially regulates the movement of the agent toward the bearing portion between the end portion of the screw portion and the bearing portion on the downstream side in the agent conveyance direction of the agent conveyance means. Since the wall is provided, it is possible to prevent the agent from entering the bearing portion, and there is an excellent effect that it is possible to prevent a torque increase and a lock due to toner adhesion.
[0054]
In addition , there is an excellent effect that the agent movement regulating means can be easily realized at low cost.
[0055]
Further, since there is no staying agent space between the specification outright wall and the bearing portion, an excellent effect that it is possible to maintain more certainly good sliding condition of the bearing portion.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a copier according to an embodiment.
FIG. 2 is a schematic configuration diagram showing a photoreceptor unit of the copier.
FIG. 3 is a perspective view showing a main part of an agent container of the photoreceptor unit.
FIG. 4 is a perspective view showing the photoreceptor unit.
FIG. 5 is a schematic configuration diagram showing an end of a first conveying screw of the same agent container.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Photoconductor drum 2 Latent image formation part 3 Developing part 4 Cleaning part 5 Agent carrying part 6 Agent accommodating part 7 Developing roller 10 Accommodating part casing 11 1st conveying screw 11a Shaft part 11b Screw part 11c End part 11d Reverse conveying part 12 1st 2 Conveying screw 24 Bearing 25 G ring 26 Partition wall 26a Small hole

Claims (4)

Agent and carrying a dosage carrying body, developer container accommodating a dosage and a stirring you conveyed while agent transport unit in the axial direction of the agent bearing member, both end portions of the rotational axis direction, respectively in the container In the image forming apparatus having in the agent conveying means a shaft portion rotatably supported by the bearing portion and a screw portion that is a conveying portion that is spirally provided on the shaft portion .
In the container, a small chamber for accommodating the end of the screw portion on the downstream side of the agent conveying direction of the agent conveying means and a partition wall for partitioning the agent accommodating portion are provided, and the shaft portion is penetrated without rubbing. A small hole is provided in the partition wall, and a reverse conveying portion that conveys the agent in a direction opposite to the screw portion is provided at a position of the bearing portion between the bearing portion and the partition wall, and the small hole and the bearing are provided. a Department is opposed through the space of the small chamber, and a feature that by the partition wall, and from the screw portion so as to at least partially restrict the movement of the agent toward the said bearing portion Image forming apparatus . The image forming apparatus according to claim 1 .
The image forming apparatus according to claim 1, wherein the reverse conveying unit includes a screw or a spiral groove. Agent and carrying a dosage carrying body, developer container accommodating a dosage and a stirring you conveyed while agent transport unit in the axial direction of the agent bearing member, both end portions of the rotational axis direction, respectively in the container The agent conveying means has a shaft portion that is rotatably supported by the bearing portion and a screw portion that is a conveying portion that spirally projects from the shaft portion, and is detachable from the image forming apparatus main body. In the image forming apparatus unit,
In the container, a small chamber for accommodating the end of the screw portion on the downstream side of the agent conveying direction of the agent conveying means and a partition wall for partitioning the agent accommodating portion are provided, and the shaft portion is penetrated without rubbing. A small hole is provided in the partition wall, and a reverse conveying portion that conveys the agent in a direction opposite to the screw portion is provided at a position of the bearing portion between the bearing portion and the partition wall, and the small hole and the bearing are provided. a Department is opposed through the space of the small chamber, and a feature that by the partition wall, and from the screw portion so as to at least partially restrict the movement of the agent toward the said bearing portion A unit for an image forming apparatus. The image forming apparatus unit according to claim 3 .
An image forming unit, wherein the agent is a developer, and the agent carrier has a developing function.

Images