JPH01179178A - Toner supplying device - Google Patents

Abstract

PURPOSE:To stably replenish a toner layer by performing plating to both end peripheral surface parts and/or both ends of a toner control member of a toner carrier and forming a prescribed gap between the image area of the toner carrier and the toner control member. CONSTITUTION:To both ends of a toner supply roll 17 of a toner cartridge 13, plating 20 is performed to prescribed thickness by an electroless nickel plating method, a metafleon plating method, etc. A toner control plate 19 is allowed to abut on the surface of this plating 20 by a spring 18. In such a way, an image forming part being in the center of the toner supply roll 17 is not brought into contact with the control plate 19 and a gap of prescribed thickness (b) is formed. Accordingly, the toner replenishment quantity from the roll 17 becomes constant, and the toner can be replenished stably.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a toner supply device that supplies toner directly to a photoreceptor or to a developing roller in an electrophotographic copying machine or an electrostatic copying machine.

Conventional Technology To form an image using a copying machine such as an electrophotographic copying machine or a printer, the surface of a photoreceptor, which is an image carrier, is first uniformly charged and then exposed to light based on a pattern corresponding to the image or data output. to form an electrostatic latent image. Next, a developing device supplies toner to the surface of the photoreceptor having this electrostatic latent image to create a phenomenon (visualization), and then the obtained toner image is transferred to a transfer material such as paper.

Such a developing device includes a developing device in which a magnetic brush of a two-component developer consisting of toner and a magnetic carrier is formed on the surface of a developer conveying member to uniformly charge and supply toner, or a developing device with a one-component developer consisting only of toner. There is a developing device that charges the toner by supplying developer to the surface of a developer conveying member and regulating the layer thickness and charge of the toner with a layer thickness regulating blade. In order to obtain high-quality images using these devices, it is important to supply a uniform thin layer of charged toner to the surface of the photoreceptor, and to this end, it is important to supply a uniform thin layer of charged toner to the surface of the developing roller.
It is necessary to form a neutral layer.

Problems to be Solved by the Invention However, in conventional developing devices, the uniform supply of developer to the photoreceptor or developing roller is not always sufficient, and it has not yet been possible to stably obtain a thin layer of well-charged toner. do not have.

In other words, in order to replenish toner in a conventional device, a thin plate is brought into contact with the surface of a toner carrier such as a developing roller or a toner supply roller while maintaining a certain angle and pressure, and a certain amount of toner is replenished depending on the balance. ing. However, such a method tends to cause abrasion due to contact (roller surface, thin plate) and toner fusion due to frictional heat, and lacks stability and durability.

Therefore, it has been proposed to eliminate contact between the developing roller and the regulating member at the toner regulating portion by providing convex portions at both ends of the developing roller and bringing the regulating member into contact with the protrusions.

However, with the method of forming a convex part at the end of the developing roller with various materials to keep the gap between the roller surface and the toner regulating member stable and constant, the convex part or the regulating member wears out due to friction, resulting in poor performance over a long period of time. You cannot drive safely. For example, with a Teflon resin spacer inserted at the end between the developing sleeve and the regulating member, the gap setting value is large, so although it can be used in parts with a wide tolerance range or in low speed ranges, It cannot be used when regulating toner or in high-speed rotating parts.

The present inventor has discovered that these problems can be solved by plating both end portions of the toner carrier, and has completed the present invention.

SUMMARY OF THE INVENTION The present invention has a toner carrier and a toner regulating member in close proximity to the toner carrier, holds a constant thickness of toner on the surface of the toner carrier, and directly or indirectly prevents an electrostatic latent image. A toner supplying device for performing development, characterized in that at least one of the circumferential surfaces at both ends of the toner carrier and both ends of the toner regulating member is plated, so that the central image area of the toner carrier and the toner regulating member are not in contact with each other. The present invention provides a toner supply device that provides a toner supply device.

Next, the present invention will be explained in more detail based on examples.

FIG. 1 is a sectional view showing an embodiment of the toner supply device of the present invention in a developing device using a two-component developer;
The figure is a sectional view showing the relationship between the toner supply roller and the toner regulating plate in a section perpendicular to this.

As shown in FIGS. 1 and 2, a developing device 1 of the present invention
Reference numeral 1 denotes a developing roller 12 which is close to a photoreceptor lOO which is an electrostatic latent image carrier, has an internal magnet 12a and supplies toner with a magnetic brush on its surface, a toner cartridge 13 which supplies toner to the roller, and a developing roller 12. It consists of a developer regulating plate 14 that regulates the height of the magnetic brush on the roller 12. The toner cartridge 13 has a toner hopper 15
A frame 16 forming a frame 16, a toner supply roller 17 rotatably provided at the bottom of the frame, and a toner regulating plate 19 pressed down by a spring 18 from the side of the cartridge 13 against the upper surface of the toner supply roller 17. have

Plating 20 is applied to a constant thickness on both ends (only one in the figure) of the toner supply roller 17, and a toner regulating plate 19 is in contact with the plating surface. Therefore, as shown in FIG.
A gap b is set without contacting the gap 9.

This gap is set so that the necessary developer is replenished during development. Note that the contact pressure of the regulating plate 19 is such that the regulating plate 19 is not pushed up by the developer passing through the gap b (5 to 109/mm).1. : Set.

As shown in the figure, the contact portion between the toner supply roller 17 and the regulation plate 19 is housed within the frame 16 so that the developer does not directly flow into the contact portion. By doing so, it is possible to prevent the developer from flowing into the contact portion between the toner supply roller 17 and the regulating plate 19, and it is possible to prevent problems such as toner fusion.

Although various types of plating may be used for plating the end portion of the toner supply roller, electroless nickel plating is preferred because the thickness of the resulting plating is very uniform and the processing accuracy of the substrate can be maintained. In addition, from the viewpoint of wear resistance, Metaflon plating (manufactured by San-Phase Rust Co., Ltd.), in which nickel as a matrix metal and fluorine-based polymer fine particles are eutectoid, is preferable. Such plating has both the excellent slipperiness of Teflon coating and the hardness of nickel. Furthermore, if a wide gap is required, another plating (metaflon plating) may be applied on top of the electroless nickel plating to form a two-layer structure.

In this embodiment, the N1 pole of the internal magnet 12a is the main developing pole, and N is the pole for scraping the toner from the toner supply roller 17. The developer regulated by the developer regulating plate 14 is stirred as shown by the arrow. That is, the toner supplied from the toner supply roller is mixed and stirred in this portion, and becomes a stable developer.

The vicinity of the phenomenon roller 12 and toner supply roller 17 is as follows:
The toner mixing ratio is set to be constant using v6 and AC voltage. (2) Depending on the value, a balance between the amount of toner supplied to the developer and the amount of toner recovered from the developer (2) can be obtained.

FIG. 3 is a sectional view showing another embodiment of the apparatus of the present invention using a one-component developer consisting only of toner.

In FIG. 3, the developing device 21 is close to the photoreceptor 100 and develops the latent image on the photoreceptor 100 by a jumping phenomenon.

The toner cartridge 23 has a frame 26 forming a toner hopper 25, a toner supply roller 27 which is a developing roller rotatably provided at the bottom of the frame, and a top surface of the toner supply roller 27.
Toner regulating plate 29 pressed down by spring 28 from the side of
has.

Note that the one-component phenomenon device of the present invention has a toner supply roller (
FEED that brings the developing roller) 27 into contact with the photoreceptor 100
It may be a developing type.

According to the developing device of the present invention, Metaflon plating is applied to the gap adjusting portions between the regulation plates at both ends of the toner supply roller, so that (1) the amount of toner supplied from the toner supply roller is reduced; This makes it possible to supply a stable thin layer of toner.

(2) The thickness of the film in the gap adjustment part is stabilized by using plating.Compared to the case where films made of metal, resin, etc. are used, variations in thickness are extremely small and production stability is excellent.

(3) It has excellent hardness, heat resistance, self-lubrication, non-adhesiveness, and abrasion resistance, so it has excellent durability and stability at high speeds.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the device of the present invention applied to a developing device using a two-component developer, Fig. 2 is a sectional view from the front, and Fig. 3 is a sectional view showing the device of the present invention applied to a developing device using a two-component developer. FIG. 3 is a cross-sectional view showing the application to a developing device to be used. The main symbols in the figure are as follows. 12: Developing roller, 13.23: Toner cartridge,
17.27: l-ner supply roller, 19.29+) toner regulation plate, 20: plating. Patent applicant Minolta Camera Co., Ltd.

Claims (3)

[Claims] (1) In a toner supply device that has a toner carrier and a toner regulating member adjacent to the toner carrier, holds a constant layer of toner on the surface of the toner carrier, and directly or indirectly develops an electrostatic latent image. 2. A toner supply device, characterized in that at least one of the circumferential surfaces at both ends of the toner carrier and both ends of the toner regulating member is plated so that the central image area of the toner carrier and the toner regulating member are not in contact with each other. (2) The developing device according to item 1 above, wherein the plating is a fluorine-based polymer-containing nickel composite plating. (3) The developing device according to item 2 above, wherein the fluoropolymer-containing nickel composite plating contains polytetrafluoroethylene resin particles or fluorinated graphite particles.