JPH0795210B2 - Non-magnetic one-component developing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a one-component developing device for an electronic copying machine, and more particularly, to a developer layer having a predetermined thickness by means of a regulating member for regulating the developer supplied onto a developer carrier. The present invention relates to a non-magnetic one-component developing device which is visualized by forming this developer layer on an electrostatic latent image on a photoconductor.

[Conventional technology]

Conventionally, in electronic copying machines, there are a cascade developing method using a two-component developer, a magnetic brush developing method, a liquid developing method, etc., but it is necessary to replace the carrier in order to prevent deterioration of charging characteristics due to long-term use, There is a drawback that maintenance of the toner concentration requires labor. In recent years, a one-component developing method using a carrier-free one-component developer for the purpose of reducing the frequency of developer exchange and downsizing of the apparatus has been widely used, and particularly high transparency non-magnetic one-component developing method. The agent has been used with good results in color development. However, the development with this non-magnetic one-component developer is not always satisfactory in terms of the developer transportability and stable transport over a long period of time.

The electronic copying machine usually has a structure as shown in the third section. Around the photosensitive drum 15, a charging corotron 16, an exposure lamp 17, a light focusing optical system 18, a developing device 19,
A transfer corotron 20, a peeling corotron 21, a static eliminator 22, and a cleaning device are sequentially arranged. Further, the paper transport system includes a paper feed cassette 28 for containing paper, a paper feed roll 29 for feeding the paper 30 from the paper feed cassette, and a photosensitive drum 15.
Paper in time with the toner image formed on the paper
A timing roll 12 is provided for feeding the 30 toward the image transfer portion. Then, in order to fix the toner image transferred onto the transfer paper by the transfer unit, a fixing device 27 having a heat fixing roll 25 is provided after the transfer process, and the fixing device 27 is ejected for accommodating a copy following the fixing device. A tray 13 is provided.

In such a copying machine, the photoconductor drum 15 rotates in the direction of the arrow, and the surface of the photoconductor drum is charged with a charging corotron before the exposure lamp 17 irradiates the image information placed on the document table 14. Evenly charged by 16. Then, the original image on the original table is irradiated with light from an exposure lamp, and the reflected light of the image is irradiated onto the surface of the photosensitive drum via the light focusing optical system 18 to form an electrostatic latent image. After that, toner is supplied from the developing device 19 to visualize the electrostatic latent image as a toner image. The toner image on the photosensitive drum thus visualized is transferred by the action of the transfer corotron 20 to the paper 30 that is fed in with timing of rotation of the drum. Then, the paper is peeled off from the surface of the photoconductor drum by removing the electric charge by the peeling corotron 21, and the fixing device 27
Once transported to. The paper that has reached the fixing device is sandwiched between the heating roll 25 and the pressure roll 26 provided so as to face the heating roll, and is heated and pressed,
The toner is melted and the toner is fixed to the sheet, and the desired copy or object is obtained and discharged to the discharge tray 31. After the image transfer is completed, the charge remaining on the toner remaining on the surface of the photosensitive drum is removed by the static eliminator 22, and then the surface of the photosensitive drum is cleaned by the cleaning blade 24 of the cleaning device 23. Then, the next copy cycle starts.

As a non-magnetic one-component developing device for the above electronic copying machine, a device as shown in FIG. 2 is conventionally known. In FIG. 2, a developer 6 is housed in a hopper, a developer carrier 1 facing the photoconductor 11, a developer supply member 2 for supplying the developer to the developer carrier 1, and a carrier Is provided with a regulating member 4 for regulating the developer layer and applying a charge of a predetermined polarity to the developer. The developer in the hopper is supplied onto the developer supply member 2 by the rotation of the developer stirring / supply member 8. The developer carrier 1 and the developer supply member 2 rotate in the directions of arrows A and B, respectively, and rotate in the same direction at their contact portions, and the developer 6 moves from the developer supply member 2 to the developer carrier 1. Transferred. The regulating member 4 contacts the carrier 1 with a uniform pressure across its axial direction, and the action of the regulating member 4 causes the developer 6 to form a developer layer 7 having a predetermined uniform thickness on the carrier. At the same time, the developer is charged. The uniform developer layer 7 pushes up the regulating member by mechanical force, and the developer carrier 1 and the regulating member 4
And is conveyed to a position facing the photoconductor 11 and electrostatically adheres to the latent image on the photoconductor for development.

[Problems to be Solved by the Invention]

In such a conventional non-magnetic one-component developing device, the amount of the developer deposited in the vicinity of the developer carrying member 1 depends on whether the developer is full or small in the hopper. However, there is a drawback that the thickness of the developer layer on the developer carrying member changes and the image quality of the copy obtained after development changes. In the former case where the developer is filled in the hopper, the space formed by the developer carrying member 1, the regulating member 4 and the developer supplying member 2 is excessively filled with the developer. There has been a problem that the smooth flow of the developer in the developing machine is obstructed, satisfactory development is not performed, and the image density is lowered and the image quality of a copy to be obtained is deteriorated.

[Means / actions for solving problems]

According to the present invention, in order to visualize an electrostatic latent image on an electrostatic latent image carrier, a developer supply member and a developer carrier which are in pressure contact with each other while rotating are provided, and further, the developer carrier is further provided. A first space portion having a regulating member for contacting the body to form a thin layer of the developer on the developer carrier and for imparting an electric charge to the developer by frictional charging; the first space portion and the opening; A non-magnetic one-component developing device having a second space portion having a member for storing the developer and conveying the developer to the first space portion, the developer filling amount in the first space portion. In order to control the development, a developing member is provided in the first space portion, the rotating member forming a developer circulation flow for returning the developer conveyed from the second space portion to the first space portion to the second space portion. Depending on the device, regardless of the amount of developer present in the hopper, By stabilizing the developer filling amount in the space and stabilizing the formation of the developer layer on the developer carrier, the above problems are solved and the image quality maintenance of the obtained copy is improved. Can be achieved.

That is, as shown in FIG. 1, a developer supply member 2 and a developer carrier 1 which are in pressure contact with each other while rotating are provided, and further a thin layer of the developer is developed by contacting the developer carrier. In a first space portion having a developing member 4 formed on the agent carrier and imparting an electric charge to the developer by frictional charging,
The rotating member 9 is provided to control excessive filling of the developer supplied from the hopper by the developer stirring / supplying member 8 into the first space by the rotating member. Further, of the developer supplied onto the developer carrying member 1, the excess developer regulated by the regulating member 4 is sequentially deposited in the first space portion, and when a certain amount or more is deposited, it is deposited on the rotating member 9. Therefore, the developer in the first space can be circulated to the hopper side. Thus the first
The amount of the developer filled in the space can be controlled, and the stable developer layer 7 can be formed on the developer carrier 1.

Hereinafter, the present invention will be described more specifically with reference to FIG. In FIG. 1, there is provided a member for storing the developer connected to the first space of the developing device with an opening by means such as a cartridge (not shown) and for transporting the developer to the first space. The developer 6 is supplied into the second space portion, that is, the hopper, and this developer is further supplied onto the developer supply member 2 by the rotation of the developer stirring / supply member 8 and the developer supply member 2 Height difference of about 200μ formed on the surface
It is filled in the concave portion of the uneven portion of m and is transferred onto the developer carrying member by pressure contact between the developer supply member and the developer carrying member.
The developer supplied onto the developer carrier 1 is given a predetermined charge by frictional charging with the regulating member 4 which is in pressure contact with the carrier, and at the same time a predetermined developer supply amount (0.3 to 1.0 mg / cm ² )
Is formed on the developer carrying member 1 and is conveyed toward the electrostatic latent image 5 on the photoconductor 11. An alternating alternating voltage, which is a direct current, is applied to a developing electrode (not shown) of a developer carrier having a coating layer such as a phenol resin to form a peripheral electric field on the electrostatic latent image portion on the photoconductor. Then, the developer in the developer layer 7 that is being sent is electrostatically adsorbed to the latent image for development.

In this way, the developer 6 in the hopper is sequentially conveyed onto the developer supplying member 2 by the rotation of the developer stirring / supplying member 8, and on the other hand, among the developers transferred onto the developer carrying member 1, Since the excess developer regulated by the regulation member 4 is fed, the developer is gradually accumulated in the first space formed by the developer carrying member, the regulation member and the developer supply member. However, by the rotating member 9 according to the present invention provided in the first space, the developer 6 accumulated in the first space is discharged to the hopper side and filled in the first space. The amount of developer is controlled to an appropriate amount. Usually, the amount of the developer existing in the hopper is gradually consumed as the developing work is continued, and therefore, there is a marked difference immediately after the developer is reinforced in the hopper and immediately before the developer needs to be replenished. . Therefore, the amount of the developer supplied to the developer supply member 2 also largely changes due to the rotation of the developer stirring / supply member 8, and stable development cannot be continued. However, according to the present invention, the rotating member 9 has a function of discharging the developer accumulated in the first space portion from the first space portion, and the developer amount in the first space portion is always an appropriate amount. Therefore, the developer layer 7 having a stable layer thickness can be always formed on the developer carrier 1 without being affected by the amount of the developer remaining in the hopper.

Factors that control the filling amount of the developer in the first space formed by the developer supply member, the regulating member, and the developer carrier include the rotation direction of the rotating member, the number of rotations, and the surface roughness of the member. The desired filling amount can be set each time by appropriately adjusting the levels of these three factors. The rotating member can be rotated by appropriately supporting the member on a developing machine and rotating the shaft by a motor (not shown) or the like.

In one example of the embodiment of the present invention, the rotation direction of the rotating member is opposite to the developer supplying member, the rotation speed is the same 196.7 rpm as the supplying member, when the surface roughness is 3.2ν, the diameter is 6 mm, Development was continued for 100 hours (process speed 100mm / Sec, equivalent to 50000 copies), but a developer layer of uniform thickness was always formed on the developer carrier without being affected by the amount of developer in the hopper. Was done.

〔The invention's effect〕

According to the present invention, a developer supply member and a developer carrier which are in pressure contact with each other while rotating are provided, and a thin layer of the developer is formed on the developer carrier by contacting the developer carrier. In addition, by providing a rotating member for controlling the developer filling amount in the first space portion in the first space portion having a regulating member for applying an electric charge to the developer by frictional charging, the first space is provided. Always stabilize the developer filling amount in the section,
Since a stable developer layer can be formed on the developer carrying member, a high-quality copy can be obtained without causing a decrease in density even in a copying operation for a long time.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a non-magnetic one-component developing device of the present invention, and FIG. 2 is a diagram showing a conventional non-magnetic one-component developing device,
FIG. 3 is a diagram showing an outline of the electronic copying machine. 1 ... Developer carrier, 2 ... Developer supply member, 3 ... Developer, 4 ... Regulator member, 5 ... Electrostatic latent image, 6 ... Developer, 7 ... Developer layer, 8 ...... Developer stirring / supplying member, 9
...... Rotating member, 10 ...... hopper, 11 …… photosensitive member.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takayuki Sunaga 2274 Hongo, Ebina City, Kanagawa Fuji Xerox Co., Ltd. Ebina Works (56) Reference JP-A-56-107274 (JP, A) JP-A-61- 129668 (JP, A) JP 57-37376 (JP, A) JP 62-136677 (JP, A) Actually opened 63-96566 (JP, U) JP 56-43813 (JP, Y2)

Claims (1)

[Claims] 1. A developer supply member and a developer carrier which are in pressure contact with each other while rotating in order to visualize an electrostatic latent image on the electrostatic latent image carrier, and further include a developer carrier. A first space portion having a regulating member for forming a thin layer of the developer on the developer carrier by contacting with the developer and for imparting electric charge to the developer by frictional charging; and the first space portion and the opening portion. In a non-magnetic one-component developing device provided with a second space portion having a member for storing the connected developer and transporting the developer to the first space portion, the developer filling amount in the first space portion is In order to control the developing device, a rotating member is provided in the first space portion to create a developer circulating flow for returning the developer transported from the second space portion to the first space portion to the second space portion. .