JPH10293463A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device capable of extremely restraining the interference of a unit other than a developing device in an image forming device and making developer exchanging work easy. SOLUTION: This device is provided with a developer container in which developer is stored and which is constituted so that the developer may be stirred and carried in the width direction of an image forming area. In such a case, a developer exchanging tank 10 is attachably/detachably attached to the outside of the image forming area on the extention of a path where the developer is stirred and carried. Then, the tank 10 is provided with carrying members 20 and 21 which can be coupled with developer carrying members 7 and 8 in the developer container 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile, and a printer, and more particularly to a developing apparatus in an electrophotographic image forming apparatus for forming an image using a two-component developer including a carrier and a toner. It is about.

[0002]

2. Description of the Related Art Hitherto, a two-component developer comprising carrier particles and toner particles which adhere to the carrier particles in a triboelectric manner has been widely used. When development is repeatedly performed using such a two-component developer, even if replenishment of an amount of fresh toner equivalent to the consumption is required, for example, it is tens of thousands to hundreds of thousands in terms of the number of images formed. It reaches the end of its life as a developer. When an image is formed using a developer that has reached the end of its life, image quality is degraded, or toner is scattered and contaminates the inside of the apparatus main body, and an abnormal image is generated due to the contamination.

Therefore, the developer whose life has expired must be replaced. Conventionally, the developing unit itself is periodically replaced as it is, or the developing unit is removed from the main body of the image forming apparatus, the lid of the toner supply unit is removed, and the deteriorated developer in the developing chamber is extracted from the opening portion of the developing unit. Things were going to be replaced. Such a developer replacement operation is left to a manual operation by a specialized maintenance worker, but is also a complicated operation for the expert.

For example, in a developing device disclosed in Japanese Patent Application Laid-Open No. 4-37781, a developing tank in which a developing roller and a stirring roller are rotatably mounted and a developer supply mechanism is provided above the developing tank. A developer discharge port is formed at the bottom of the tank, a lid that allows the discharge port to be opened and closed is provided, and a developer collecting scraping section is formed on the lid, and the lid is used as a discharge port when the developer is replaced. Switching control is performed between a developer recovery position in which the scraping portion is opened to abut the developing roller and a developer stirring position in which the discharge port is closed during the developing operation and the flow of the developer is regulated by the scraping portion. A developing roller provided in a container provided with an exchange control unit or in a container containing a two-component developer disclosed in JP-A-7-110623;
A developing device provided with at least a plurality of developer stirring / conveying members parallel to the developing roller, wherein the developer stirring / conveying member agitates and conveys the two-component developer to supply the developing roller to the developing roller; A configuration in which a discharge port for discharging used developer is provided at at least one end of both ends of the bottom of the container has also been proposed from the viewpoint of facilitating the developer replacement work as described above. .

[0005]

However, in both of the above proposals, when the developer is replaced, a container for collecting used developer is attached to the lower portion of the developing device, while a container for replenishing new developer is provided. It requires a complicated operation of attaching it to the upper part of the developing device. Further, the container to be used also protrudes and is attached to the upper and lower spaces of the developing device, so that interference with other units in the image forming apparatus is inevitable. In a recent image forming apparatus which is downsized for saving space, the existence of such a container poses a problem in itself.

Accordingly, it is an object of the present invention to provide a developing device capable of minimizing the interference of units other than the developing device in the image forming apparatus, and in which the operation of replacing the developer is easy.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided a developing apparatus comprising a developing container for containing a developer and stirring and transporting the developer in a width direction of an image forming area. A developer exchange tank is detachably attached to the outside of the image forming area on the extension of the stirring and conveyance of the developer, and the developer exchange tank is provided with a transport unit connectable to the developer transport unit in the developer container. It was solved by configuring.

It is advantageous if the transport means provided in the developer exchange tank is driven by the developer transport means in the developer container. Further, if a lid member for opening and closing the developer container side end surface of the developer exchange tank is detachably provided, or a lid member for opening and closing the developer exchange tank side end surface of the developer container is detachably provided,
It is suitable. It is even better if an opening for supplying toner is provided on the upper surface of the developer exchange tank.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described based on an embodiment shown in the drawings. Of course, the following examples illustrate the present invention and do not limit the technical scope of the present invention.

FIG. 1 shows a schematic configuration around a photosensitive drum of an image forming apparatus using a developing device according to the present invention. The developing device 2 transports a developer 6 in the developing device 3 to a developing nip area 4 facing the photosensitive drum 1 by a developing roller 3.
The toner is made to adhere to the electrostatic latent image formed on the photosensitive drum 1 so as to be visualized. The toner image is transferred onto a transfer sheet in a transfer area 18 where the photosensitive drum 1 and the transfer device 17 face each other, and becomes an image on the transfer sheet.

In a developing container 5 which supports the developing roller 3 and stores the developer, in addition to the developing roller, a first developer conveying member 7 and a second developer conveying member which are parallel to the developing roller. 8 are arranged. The second developer transporting member 8 disposed apart from the developing roller 3 allows the toner replenished into the developing container 5 from a toner replenishing device (not shown) to have a uniform concentration in the developer without unevenness. Further, the developer is conveyed, for example, from the near side to the far side of the paper while stirring to raise the charge amount of the toner by frictional charging. The first developer conveying member 7 arranged near the developing roller 3 includes:
While supplying the developer having the uniform toner concentration as described above to the developing roller 3, the developer is conveyed from the back side to the front side. Due to the rotation of the developing roller 3 and the movement of the first developer transport member 7, the developer which has been used for development and whose toner concentration has been reduced is also gradually transported to the near side. A partition plate 9 is provided between the two developer conveying members 7 and 8 so that the developers conveyed by the respective conveying members do not mix with each other. The partition plate does not extend, and forms a distribution path that allows the transported developer to be delivered to the other transport member.

As can be understood from FIG. 2, which is a plan view of the developing device according to the present invention, the lower side of the image forming area (A) in the axial direction of the photosensitive drum (in front of the sheet of FIG. 1). A developer replacement tank 10 is disposed outside the developing container 5. The developer replacement tank 10 is detachable from the developing container 5,
In addition, the third and fourth developer conveying members 20 and 21 are arranged in portions that are located in the extended regions of the first and second developer conveying members 7 and 8 when the developing device is mounted on the developing container 5. The third developer conveying member 20 is connected to the first developer conveying member 7 through the joint 23.
And the fourth developer conveying member 21 is also fitted with the second developer conveying member 8 via the joint 23,
The rotation of the first and second developer conveying members 7 and 8 is transmitted to the third and fourth developer conveying members 20 and 21, and the developer is moved in the same direction as the first and second developer conveying members 7 and 8, respectively. Can be transported. Developer transport member 2 in developer replacement tank 10
The developing container sides 0 and 21 are supported by a conveying member supporting member 22 protruding from the tank bottom plate. As shown in FIG. 3, a lid member 12 for shielding a space other than the conveying member supporting portion of the opening 11 communicating with the developing container side is arranged to be removable from above the tank. When the developer replacement tank 10 is mounted on the developing container 5, the lid member 12 is removed, and the opening 11 opens the developing container 5 and the tank 1.
0, the developer conveyed by the first developer conveying member 7 is transferred to the third developer conveying member 20, and the fourth developer conveying member 21 transfers the developer to the second developer conveying member 8. The developer is transferred to the developer, and a developer circulation path is formed as a whole. A partition plate 25 corresponding to the partition plate 9 of the developing container is also disposed between the third and fourth developer conveying members 20 and 21, and is disposed at the lowermost position in FIG. (Corresponding to the side) does not reach the partition plate 25, thereby securing a developer circulation path. A toner supply port 24 is opened on the upper surface of the developer replacement tank 10. Through this, the toner discharged from a toner supply device (not shown) is supplied to the developing device. The toner replenishment area is provided at a position farthest from the image forming area, so that the toner and the developer can be mixed before being used for image formation.
Stirring will be sufficient.

On the other hand, on the side of the developing container 5, as shown in FIGS. 2 and 4, the tank-side end portions of the first and second developer conveying members 7, 8 project from the lower case of the developing container. 13 supported. A partition member 14 for shielding the container opening surface other than the support member 13
Are arranged to be removable from above the developing container 5 (FIG. 4).

When the image forming operation is not being performed, the lid member 12 is attached to the developer replacement tank 10 and the developer container 5 is replaced.
Then, the developer replacement tank 10 is detached from the developing container 5 and removed, and the developer replacement tank 10 containing the new developer is mounted on the support tray 16 of the developing device. The lid member 1 is connected to the developing container 5.
2. It is performed by extracting the partition member 14. In order to prevent the developer from leaking out of the developing device and scattering during the image forming operation, as shown in FIG. 5, the opening formed by removing the lid member 12 and the partition member 14 is closed. The seal member 15 is attached. In the illustration in FIG. 2, the partition plate 9 extends almost to the boundary with the developer replacement tank 10, but if the partition plate 9 is arranged so that a blank portion remains between the boundary and the boundary. In addition, the developer can be replaced without stopping the operation of the image forming apparatus.

[0015]

According to the present invention, a developer exchange tank is detachably mounted outside the image forming area on the extension of the stirring and transport of the developer, and the developer in the developer container is provided in the developer exchange tank. Since the transfer means is provided with a transfer means which can be connected to the transfer means, interference of units other than the developing device in the image forming apparatus can be suppressed, and the operation of replacing the developer can be performed smoothly. By the presence of the transport means in the tank, it is possible to mount the tank for replacing the developer even during a normal image forming operation, and by adjusting the control of the developer transport, it is possible to install the tank in the tank. It is possible to freely change the amount of the developer for replacement.

If the transfer means provided in the developer exchange tank is driven by the developer transfer means in the developing container, it is not necessary to provide a separate drive device for the transfer means. Can be simplified. Also, if a lid member for opening and closing the developer container-side end surface of the developer exchange tank is detachably provided, or a lid member for opening and closing the developer exchange tank-side end surface of the developer container is detachably provided, when the tank is removed. In addition, the leakage of the developer from the developing container or the tank can be avoided, and the replacement operation becomes easy. Further, if an opening for supplying toner is provided on the upper surface of the developer exchange tank, the supplied toner can be sufficiently mixed and agitated with the developer before reaching the image forming area, and the charge amount of the toner can be increased. Can be sufficiently started, and the image quality can be maintained satisfactorily.

[Brief description of the drawings]

FIG. 1 is a schematic diagram around a developing device and a photoconductor.

FIG. 2 is a schematic plan view of a developing device portion.

FIG. 3 is a schematic perspective view of a developer replacement tank.

FIG. 4 is a schematic perspective view illustrating a state in which a developer replacement tank is removed from a developing device.

FIG. 5 is a schematic perspective view illustrating a state in which a developer replacement tank is mounted on a developing device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor drum 3 developing roller 5 developing container 7 first developer transport member 8 second developer transport member 9 partition plate 10 developer replacement tank 20 third developer transport member 21 fourth developer transport member 25 partition plate

Claims (5)

[Claims] 1. A developing device comprising a developing container for accommodating a developer and agitating and transporting the developer in a width direction of an image forming area, wherein the developing device includes a developing container outside the image forming area when the agitating and transporting of the developer is extended. A developer exchange tank is detachably attached to the developer exchange tank, and the developer exchange tank is provided with a transport unit connectable to the developer transport unit in the developing container. 2. The developing device according to claim 1, wherein said transport means provided in a developer exchange tank is driven by a developer transport means in a developing container. 3. The developing device according to claim 1, wherein a lid member that opens and closes an end surface of the developer exchange tank on the side of the developing container is detachably provided. 4. The developing device according to claim 1, wherein a lid member that opens and closes an end surface of the developing container on a developer exchange tank side is detachably provided. 5. An apparatus according to claim 1, wherein an opening for supplying toner is provided on an upper surface of said developer exchange tank.
The developing device according to claim 1.