JP2001318518A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform toner stirring action in a developing device in an excellent state and to prevent deviation in the distribution of toner supplied toward a photoreceptor drum by enhancing the feeding performance of an agitator for stirring and feeding the toner in a toner container. SOLUTION: As for the agitator 12 rotated in the toner container of the developing device and stirring and feeding the toner, additional sheet pieces 17a and 17b are separately attached to both ends of a rotating body 16 in a stirring member 17 constituted by providing many sheet pieces 18 on the rotating body 16, so that toner stirring force inside the toner container can be strong. The stirring force at the side part of the toner container is set to be strong by the additional sheet piece so as to prevent the deviation in the distribution of the toner in the container.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agitator for agitating and feeding toner in a toner container of a developing device, which can perform a good stirring action at both ends of the toner container.

[0002]

2. Description of the Related Art In an image recording apparatus using an electrophotographic system, a toner image is formed on a photosensitive drum, and the toner image transferred onto paper is fixed through a fixing device and discharged as recording paper. I have. In the image forming apparatus, information obtained by reading an image of a document on a photosensitive drum is directly irradiated with reflected light or converted into laser light and irradiated to form an electrostatic latent image, and the electrostatic latent image is formed. Means for visualizing the latent image by attaching toner to the latent image is used. In order to supply the toner to the photosensitive drum, a developing device is disposed. In the developing device, a developing roller disposed to face the photosensitive drum, and a developing device for supplying the toner to the developing roller. Supply means such as an agitator of
Means is provided for supplying an appropriate amount of toner contained in the toner containing section toward the developing roller via the supply roller. In a toner supply unit provided in a general developing device, the toner is sent out while being stirred by an agitator or the like in a toner container. The agitator is configured by attaching a flexible sheet piece to a rotating body. I have. Then, it is possible to prevent the toner from remaining on the wall of the storage section such as the hopper or to prevent the toner from causing a bridging phenomenon inside the container, so that a fixed amount of the toner can be supplied to the developing roller.

[0003]

However, it is necessary to supply a large amount of toner at the center of the developing device to the recording paper created by a general image forming apparatus, but it is necessary to supply a large amount of toner at both sides in the paper moving direction. Since an image is rarely formed, the amount of toner to be supplied tends to be small. Therefore, when the toner is sent out from the toner container of the developing unit by the agitator, the toner remains accumulated at both ends due to a small amount of the toner to be sent out. A problem arises that it is difficult to get rid of it. Further, when the distribution of the toner becomes uneven in the toner container, the amount of the toner supplied to the developing roller is not constant in the length direction of the developing roller, and the amount of the toner to be developed on the photosensitive drum is reduced. There is a possibility that a defect occurs in the image quality of the obtained toner image.

An object of the present invention is to provide a means for improving the stirring performance of the agitator on both sides in the toner container so that the toner can be uniformly supplied to the developing unit.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a developing device for supplying a toner to a developing roller while stirring the toner by an agitator provided inside a toner container. According to the invention of claim 1 of the present invention, a stirring member is provided by connecting a number of flexible sheet pieces to a rotating body of an agitator rotatably disposed inside a toner container, and the stirring member is provided at an end of the stirring member. A plurality of sheet pieces are provided at intervals in the circumferential direction of the rotating body. Therefore, the rotational torque of the agitator does not become excessively large, and the toner agitating property at the end of the toner container can be improved.

According to a second aspect of the present invention, the sheet pieces disposed at both ends of the rotating body of the agitator are attached to the axis of the rotating body so that a component force acts on the toner in the container lateral direction as the rotating body rotates. It is characterized by being mounted diagonally to it. And
Since a component force acting to move the toner in the lateral direction acts in the toner container, the stirring property can be further improved.

According to a third aspect of the present invention, as the sheet pieces disposed at both ends of the rotating body of the agitator, two sheet pieces are attached at an interval of 180 °, and the acting directions of the component forces are opposite to each other. It is characterized by having such a configuration. Therefore, the movement of the toner in the left and right directions at both ends of the toner container is promoted, and the toner stirring action is performed more uniformly.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the apparatus of the present invention will be described with reference to the illustrated example. The example shown in FIG. 1 shows the configuration of an apparatus in which a developing unit and a photosensitive drum are combined, and is configured as an image recording apparatus such as a facsimile machine or an electrophotographic copying machine. In the apparatus shown in the present embodiment, two units of the developing unit 10 and the photosensitive unit 20 are combined and mounted on the image recording apparatus main body.
The developing device unit 10 and the photoreceptor unit 20 are configured as individually detachable units. In the developing unit 10, the toner is sent out by rotating the agitator 12 provided in the toner container 11 containing the toner in the clockwise direction (the direction of the arrow in the figure). Then, the toner container 11
The toner sent out from the agitator 12 through the communication port 11 a is exposed at a position facing the photosensitive drum 21 via the supply roller 13 and the developing roller 14.

In the developing unit 10, the toner sent from the toner container 11 toward the supply roller 13 is supplied between the two rollers by rotating the supply roller 13 and the developing roller 14 in the same direction. And is electrically attached to the surface of the developing roller 14. The toner adhering to the developing roller 14 is formed into a thin layer having a predetermined thickness by the layer thickness regulating member 15, and is exposed at a position corresponding to the photosensitive drum, thereby forming an electrostatic latent image formed on the photosensitive drum. Attached to the image to form a toner image.

In the photoconductor unit 20 arranged with respect to the developing unit 10, a writing device 22, a charging member 23, a memory removing member 24 and a transfer roller 25 are arranged with respect to the photoconductor drum 21. . Then, with the photoconductor unit 20 attached to the image recording unit, the photoconductor drum 21 is positioned with respect to the transfer roller 25 disposed at a fixed position of the main body frame and the developing roller 14 of the developing device 10. You. In the example of the illustrated photoconductor unit 20, unlike a general large-sized image recording apparatus, it is configured as a cleaner-less type apparatus without a cleaning device. In this type of apparatus, after the toner image formed on the photosensitive drum is transferred onto paper, the toner remaining on the drum surface is disturbed by the biased memory removing member 24,
The toner is returned to the developing device, mixed with the newly supplied toner, and reused.

The toner container 11 of the developing unit 10
The agitator 12 provided in the inside, as shown in FIG.
A rotating body 16 having a rectangular cross section is fixed to rotating shafts 16a and 16b projecting from both ends, and a stirring member 17 constituted by arranging a large number of sheet pieces on one surface of the rotating body 16 is attached. The sheet member of the stirring member 17 is formed by connecting a number of flexible plastic sheet members without gaps, and one end of the sheet member is fixedly held to the rotating body 16. The free end is formed so as to be easily bent. By rotating the rotating body 16, the stirring member 17 is moved to the toner container 1.
1 stirs the toner contained in the container 1 and sends it out to the communication port 11 a of the container 11. The sheet piece constituting the stirring member 17 may be formed by providing slits at predetermined intervals on a member such as a thin and elastic film. Examples of the sheet piece include Mylar and Lumirror (both are trade names)
It is possible to use a film-like or sheet-like member as described above, or a plate-like member capable of exhibiting the same elasticity and strength. The toner is stirred inside the toner container 11 and the supply roller 13 is supplied from the communication port 11a. To send out the toner toward.

In the example shown in FIG. 2, an additional sheet piece 17a is provided on the other surface of the end of the rotating body 16 with respect to the stirring member 17 in which a number of sheet pieces are arranged and attached to the rotating body 16. , 17b are additionally arranged, and the rotating body 16
Means for improving the agitating force on the toner at both ends. The additional sheet pieces 17a, 17b
Is attached to the rotating body 16 using a double-sided tape or an adhesive, similarly to the sheet piece of the stirring member 17, using a sheet piece made of the same material as that used as the stirring member 17. Can be. By arranging the additional sheet pieces 17a and 17b only at both ends of the rotation shaft, the toner agitating action at the side portion of the container is more favorably performed than when only the stirring member 17 is provided. be able to.

The example of the agitator 12a shown in FIG. 3 is an additional sheet piece 18, 18a arranged at the end of the rotating body 16.
Is attached at an angle to the longitudinal direction of the shaft. In FIG. 3, the rotating body 16
Although the arrangement state of the additional sheet piece at one end of is shown,
Similarly, by attaching the sheet piece at an angle to the other end of the rotating body 16, the toner can be sufficiently agitated in the toner container. When attaching the additional sheet pieces 18, 18a, the rotating body 16
It is also possible to use means such as forming oblique slits at both ends of the sheet and inserting and fixing a long sheet piece in the slits, but any other fixing means can be used. When the additional sheet piece disposed obliquely is provided, an action (component force) of moving the toner toward the outer wall of the container is applied to the additional sheet piece 18 with respect to the rotation of the rotating body. And other additional sheet pieces 18
In (a), a component force is applied to the inside of the container, so that the toner can be satisfactorily stirred inside the toner container.

In the example of the agitator 12b shown in FIG. 4, additional sheet pieces 19 and 19a are arranged at the end of the rotating body 16 with respect to the stirring member 17, and the same stirring action as in FIG. Is performed. Also in the above embodiment, any fixing means can be used to attach the additional sheet pieces 19 and 19a to the end of the rotating body 16, and the additional sheet pieces 1 attached at an angle can be used.
9 and 19a, the action of moving the toner in the left-right direction with respect to the rotating body 16 is added, and the stirring action of the toner can be favorably performed.

As shown in each of the above-described embodiments, by adding a sheet piece to the stirring member 17 provided on the rotating body 16, compared with the case where the sheet pieces are arranged in a single line, the toner container can be used in the toner container. It is possible to perform the toner agitating action more favorably. Further, by providing each of the additional sheet pieces, the stirring performance of the toner on the side of the container is improved, and the toner that tends to remain in the end of the container is moved toward the center of the container. Can also be performed. Accordingly, the toner sent from the toner container 11 to the supply roller 13 through the communication port 11a is not biased, and the toner supplied from the supply roller 13 is uniformly adhered to the developing roller 14 so that the photosensitive drum Can be made to correspond.

As described above, by constructing the developing device, for example, when a large number of recording papers are continuously formed, the consumption of toner on both sides of the recording paper is small, and the amount of toner consumed at the intermediate part is small. Even when the toner consumption is large, the toner that easily stays on both sides of the toner container can be strongly stirred. Then, the occurrence of bias in the toner distribution inside the toner container of the developing device is eliminated, and the communication port 11 of the toner container is removed.
a, the toner can be sent out evenly.

The agitator 12 provided with the stirring member 17 configured as described above can be arranged in the developing unit 10 shown in FIG.
An image forming apparatus combined with the photoconductor unit 20 combined with 0 can be applied to an image forming apparatus as shown in FIG. In the image forming unit of the image forming apparatus 1 shown in FIG. 5, a sheet feeding unit from the sheet feeding tray 2 is provided at a lower part of the apparatus, and an image forming unit using an electrophotographic method is arranged at an upper part. In the paper feed unit, paper is fed one by one by a paper feed roller 3 disposed on a paper feed tray 2, and is conveyed in a paper conveyance path 4 by conveyance roller devices 5 and 6 to a toner image transfer unit. And send it out. An image forming unit arranged above the image forming apparatus 1 is provided with a combination of a developing unit 10 and a photoconductor unit 20.

In the developing unit 10 arranged in combination with the photoreceptor unit 20, the toner container 1
The toner contained in 1 is sent out to the supply roller 13 while being agitated by the agitator 12, and is rubbed with the supply roller 13 between the developing roller 14 which rotates in the counterclockwise direction in FIG. The toner is charged as a thin layer on the surface of the developing roller 14 while being charged. The toner adhered to the surface of the developing roller 14 is formed as a thin layer having a certain thickness by a blade member, and the toner adheres to the electrostatic latent image of the photosensitive member at a portion where the toner contacts the photosensitive member 21. The image is visualized as a toner image.

A transfer roller 25 for transferring the toner image formed on the photoreceptor 21 to a sheet is disposed on the photoreceptor unit 20 arranged in combination with the developing unit 10. Around the photoconductor 21, a transfer roller 25, a brush-like memory removing member 24, a charging roller 23 and a writing device 22 configured as a brush roller are arranged according to the rotation direction of the photoconductor 22. You. Then, a charging unit 23 is applied to the photoconductor 21.
And the writing means 22 irradiates light of image information to form an electrostatic latent image. The developing roller 1
The toner adhered to the surface of the photoconductor 4 is formed as a thin layer having a certain thickness by a blade member, and the toner is adhered to the electrostatic latent image of the photoconductor at a portion that comes into contact with the photoconductor 21,
It is visualized as a toner image. The toner image formed on the photoconductor is transferred by applying a predetermined voltage to the transfer member when the paper passes between the photoconductor 21 and the transfer member 25.

The sheet carrying the toner image is conveyed toward the fixing device 7, and is heated by a heat roller 7a and a pressure roller 7b.
And is discharged toward the discharge tray by the discharge roller device 8. The image forming apparatus 1
In the writing information supplied to the writing member 22,
Image information from an image reading apparatus (not shown) provided in combination with the image forming apparatus 1 or a digital signal received by facsimile through a telephone line is used to cause the LED element of the writing member 22 to emit light in a dot-like manner. The image information is written on the photoconductor. In the image forming unit of the image forming apparatus 1, after the toner image is transferred from the photoconductor to the paper without providing a cleaning device for the photoconductor 21, the remaining toner memory is disturbed to reduce the adhesive force. It is configured as a so-called cleaner-less type image forming apparatus that is weakened and collected in a developing unit and reused.

[0021]

Since the apparatus of the present invention is constructed as described above, in addition to the stirring member provided on the agitator, a plurality of sheets are provided on the end of the stirring member in the circumferential direction of the rotating body. By providing the pieces at intervals, the rotational torque of the agitator does not become excessively large, and the toner stirring at the end of the toner container can be improved. Further, the additional sheet piece is attached obliquely with respect to the axis of the rotating body so that a component force acts on the toner in the lateral direction of the container with the rotation of the rotating body, so that the toner can be horizontally moved in the toner container. Because the component force acts to move in the direction,
Stirring properties can be further improved. Further, in a case where the additional sheet pieces are attached such that two sheet pieces are attached at an interval of 180 °, and the action directions of the component forces are opposite to each other, the toner at both ends of the toner container is The movement in the left-right direction is promoted, and the stirring action of the toner is performed more uniformly.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a configuration of a developing device.

FIG. 2 is an explanatory diagram showing a configuration of an agitator.

FIG. 3 is an explanatory view showing another configuration of the agitator.

FIG. 4 is an explanatory diagram showing another configuration of the agitator.

FIG. 5 is an explanatory diagram of an example of an image forming apparatus to which the present invention can be applied.

[Explanation of symbols]

1 image forming apparatus, 2 paper cassette, 3
Paper feed roller, 4 paper transport path, 5.6 transport roller device, 7 fixing device, 8 discharge roller device,
Reference Signs List 10 developing device, 11 toner container, 12 agitator, 13 supply roller, 14 developing roller, 16 rotating body, 17 stirring member, 17a-1
8.19 additional sheet pieces, 20 photoreceptor units, 21 photoreceptor drums, 22 writing devices,
23 charging roller, 24 memory removing roller, 2
5 Transfer roller.

Claims (3)

[Claims] 1. A developing device for supplying toner to a developing roller while agitating the toner by an agitator provided inside a toner container, wherein a plurality of rotating bodies of the agitator rotatably arranged inside the toner container are provided. A developing device, wherein a stirring member is provided by connecting flexible sheet pieces, and a plurality of sheet pieces are provided at an end of the stirring member at intervals in a circumferential direction of the rotating body. 2. A sheet piece disposed at each end of a rotating body of the agitator is attached obliquely with respect to the axis of the rotating body so that a component force acts on the toner in a lateral direction of the container as the rotating body rotates. The developing device according to claim 1, wherein: 3. As the sheet pieces disposed at both ends of the rotating body of the agitator, two sheet pieces are attached at an interval of 180 ° so that the acting directions of the component forces are opposite to each other. The developing device according to claim 1, wherein: