JPS59125761A - Developing device - Google Patents

Abstract

PURPOSE:To prevent coagulation of a developer even under a high temperature environment by forming the magnetic line of force of a magnetic pole in a developer regulating area so as to be inclined from the turning direction of a sleeve. CONSTITUTION:A napping regulating plate 26 is arranged with prescribed interval so as to be close to the external periphery of the sleeve 22 and the developer D carried to the sleeve 22 is regulated to a prescribed developing thickness by the fine interval and carried to a developing part. Submagnetic poles 24S, 24N are arranged in the sleeve 22 so as to put the sleeve between these magnetic poles at the positions opposed to the napping regulating plate 26. Since the submagnetic poles 24S, 24N are magnetized with inclination, the magnetic lines of force generated by the submagnetic poles 24S, 24N are inclined from the moving direction of the developer D, i.e. in the arrow direction. If the magnetic developer D is carried to the external periphery by turning the sleeve 22, the developer D is influenced by the inclined magnetic lines of force in accordance with the advancement on the upper part of the submagnetic poles 24S, 24N and changes its nap direction in the arrow direction. The inclined napping of the developer D is abutted to the back of the napping regulating plate 26 and has vertical motion against the carrying direction of the developer D. The movement of the developer D applies shearing force to the coagulated toner coagulated on the back of the napping regulating plate 16 and grinds the coagulated toner, so that the toner is prevented from being stopped up.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a developing device in an electrostatic recording device, such as an electrophotographic copying machine.

More specifically, the present invention relates to a developing device that improves image quality by preventing agglomeration of developer that occurs in a developer thickness regulating portion in a magnetic brush developing device.

In electrostatic recording devices such as electrophotographic copying machines, electrostatic printers, and electrostatic facsimiles, an electrostatic latent image of an image to be recorded is formed on a charge carrier such as a photoreceptor or dielectric, and this electrostatic latent image is is developed into a visible image using a developer containing toner. The device used for this development is the developing device.
Various types of developing devices are currently known. FIG. 1 shows a developing device known as a magnetic brush developing device.

The developing device 1 includes a conductive developer holding member (hereinafter referred to as a sleeve) inside a developing device main body 11 that stores developer.
12 is provided rotatably in the direction of the arrow. Inside the sleeve 12, there is one main magnetic pole 13 and a plurality of sub magnetic poles 1.
4 is fixed to the magnetic pole holder 15 with a slight distance from the sleeve 12. A portion of the sleeve 12 is disposed in the opening 11A of the developing device body 11 close to the rotating drum 2 having a charge carrier 2A made of a photoreceptor or a dielectric on its surface, and this close position is the developing position. At the top of the developing device main body 11, a spike regulating plate 16 is provided that regulates the thickness of the developer layer conveyed to the developing position by the sleeve 12. The agent is applied to a predetermined layer thickness.

In such a developing device, when the sleeve 12 rotates, the developer layer is regulated to have a constant thickness by a spike regulating plate 16.

The developer layer thus conveyed by the sleeve 12 stands up like a bluff when it approaches the position of the main magnetic pole 13. These bluff-like developer spikes dampen the vibrations on the surface of the charge carrier 2A. When an electrostatic latent image is formed on the charge carrier 2A, the toner in the developer is absorbed by the electrostatic latent image by electrostatic attraction, and the electrostatic latent image becomes a visible image.

The developer used in this type of developing device includes magnetic powder such as iron powder (Ki↑Ryan) and colored synthetic resin powder (toner).
There are two-component developers, which consist of a two-component developer, and a one-component developer, which is a synthetic resin powder mixed with a colorant and magnetic powder. - A component type developer does not contain a carrier, so it consists only of particles having a smaller particle size than a two-component type developer. Therefore, the distance between the spike regulating plate 16 and the sleeve sum is selected to be 0.5 m or less, which is conveniently smaller than about 1 to 5 B in the case of a two-component developer. Therefore, the -component type developer has a tendency to clump by itself, and since pressure is applied at the narrow regulating part, it is even more likely to clump.Since the gap between the developing sleeve and the regulating plate is narrow, even a slight clump can cause the clumps to appear in Figure 2. As shown in the figure, there is a problem in that clogging occurs and density unevenness occurs in the vertical direction. If a lump of developer is mixed in, the spike regulating plate 16 and sleeve 12
If there is a blockage between the two, the developer is not conveyed to that area, and development is likely to fail (appears as a white vertical line on the copy). This phenomenon is particularly likely to occur when an insulating toner is used as the developer.

Conventionally, methods have been used to prevent such lumps from forming in the developer, such as scraping off the developer from the developing sleeve or stirring the developer as described above. Countermeasures include removing the developer from the developer container and placing it in a sieve during maintenance, or removing the developer from the recording device and cleaning the developer transport section by hand to remove foreign objects. There is, but like this-
These operations are extremely troublesome, and the biggest advantage of component-based developers, which is maintenance-free, is lost.
There is a problem in that the efficiency of recording work is significantly reduced.

Therefore, a method has been proposed in which the foreign matter is easily removed by throwing a cleaning member at the spike regulating section and operating the cleaning member from the outside (Japanese Patent Application No. 168,069/1982).

However, even with the foreign matter removal method using the cleaning member, there is a problem in determining the timing and frequency of implementing this method, and the operation is cumbersome because it is manually operated by a person.

In view of the above points, the present invention is designed to disintegrate the aggregated developer in the developer thickness regulating section. This was done to prevent agglomeration.

That is, the present invention is for developing an electrostatic latent image surface by conveying developer while attracting it onto the periphery of a rotatable sleeve having a built-in magnetic pole that generates magnetic force, and using a constant amount of developer to develop an electrostatic latent image surface. Provided is a developing device equipped with a regulating member, characterized in that lines of magnetic force of the magnetic poles in a developer regulating region on the sleeve are formed to be inclined with respect to the rotational direction of the sleeve. It is something to do.

According to the present invention, the developer near the spike regulating plate, which is the developer regulating area, can also move in the direction perpendicular (lateral) to the developer conveyance direction, and this movement of the developer causes the spike regulating plate to move. Toner clogging is prevented by applying shear force to the agglomerated developer (toner) stuck on the back surface to crush it. This solves the above-mentioned problem of unevenness in the vertical direction.

The present invention will be specifically explained below with reference to examples shown in 15 drawings.

FIG. 3 is a perspective view showing a sub magnetic pole built into a developer holding member (sleeve) applied to the developing device of the present invention;
Figure 4 is a side view and a front view ω). In these figures, the sub magnetic poles 24S and 24N are magnetized obliquely with respect to the conventional magnetization direction, and have an angle α1.
α, respectively indicate the magnetization angle.

FIG. 5 is a sectional view showing the relationship between the developing roller and the spike regulating plate section in the developer regulating section in a fixed magnet/sleeve rotating type developing device.

Here, the spike regulating plate is provided close to the outer peripheral surface of the sleeve n at a predetermined interval, and the developer layer conveyed to the sleeve 22 is regulated to a predetermined developed thickness by this minute interval. The image is transported to the developing section. On the other hand, inside the sleeve n, the sub-magnetic poles 24S and 24N according to the present invention are disposed with the sleeve η sandwiched between them at a position t that faces the edging regulating plate portion. The setting position of the ear standing regulation plate % is the sub magnetic pole 24.
It is not limited to the central part of 8.24N.

FIG. 6 shows a top view of the developer regulating portion of the sleeve n incorporating the sub magnetic poles 24S and 24Nk according to the present invention. Since the sub-magnetic poles 248.24N are magnetized obliquely as shown in FIGS. 3 and 4, the lines of magnetic force caused by this are oblique to the direction of movement of the developer layer as shown in FIG. It is formed in the direction. When the sleeve ρ is rotated and the magnetic developer (two-component developer or one-component developer) D is conveyed onto its outer peripheral surface, the developer is transferred to the sub magnetic pole 248.2.
4N, the direction of the ear changes in the direction of the arrow in FIG. 6 under the influence of the oblique magnetic field lines.

Here, the spike regulating plate portion fixed approximately in the middle of the sub-magnetic pole 248.24N prevents the developer from rising in the diagonal direction, so that the spike regulating plate hits the back surface of the developer and moves in the developer transport direction. It has a vertical motion. This movement of the developer applies a shearing force to the aggregated toner stuck on the back surface of the spike control plate 16 to break it up, thereby preventing toner clogging.

The above-mentioned magnetization angle α must be set so that the magnetization directions of the sub magnetic poles 248 and 24N are not parallel to each other, and it is particularly desirable that the magnetization angles be in directions that intersect with each other. In addition, the magnetization α is set at 20' to
60' is preferred.

Further, in FIG. 5, magnetic poles with different polarities are arranged in parallel, but magnetic poles with the same polarity may be arranged in parallel. A similar effect can be achieved by using similar diagonally magnetized magnetic poles. Incidentally, the ear standing regulation plate 16 may be made of a magnetic material.

Furthermore, one other magnetic pole, for example, a conveying magnetic pole, may also have a similar configuration (oblique magnetization).

This is particularly effective in promoting uniform charging of toner in a -component magnetic developer. Of course, false and α do not have to be the same. Furthermore, only one of the magnets may be obliquely magnetized.

The above-described embodiments of the present invention relate to a developer regulating section of a fixed magnet/sleeve rotating type developer conveying means.
Same as this! It can also be applied to a type in which the magnet contained in the MK sleeve rotates. FIG. 7 shows a second embodiment of the present invention, FIG. 7(4) is a cross-sectional view of a rotary magnet type developing device, and FIG. 7(B) is a rotatable magnetic roller enclosed in a sleeve 32. FIG. The sleeve 32 may rotate in the same direction as the magnetic roller or in the opposite direction. The magnet groups built into the magnetic port are normally magnetized alternately. These magnets 33N and 338 are each obliquely magnetized, and as shown in FIGS. 3 and 4, the magnets are formed so that their magnetization directions intersect. A magnetic roller composed of a plurality of groups of magnets that are diagonally magnetized and arranged in an NS alternating pattern forms a diagonal magnetic force at as shown by the arrow in FIG. 7 (13).

When this magnetic roller is rotated and the magnetic developer on the outer periphery of the sleeve 32 is conveyed, the developer is influenced by the above-mentioned oblique magnetic field lines, and the direction of the ears of the developer changes as shown in FIG. 7 (J3). Change in the direction of the arrow. When the developer further advances and hits the back surface of the spike regulating plate portion of the developer regulating section, the oblique spikes of the developer begin to move perpendicularly to the conveyance direction. This lateral movement of the developer applies a shearing force to the aggregated toner attached to the back surface of the spike control plate 36 to break it, thereby preventing toner clogging.

FIG. 8 is a side view (4) and a front view (6) showing another embodiment of the magnet forming a part of the magnet-rotating magnetic roller according to the present invention. NS A set of magnets 438 alternately magnetized
．． 43N are each obliquely magnetized, and the lines of magnetic force indicated by the arrows are formed and arranged in parallel as shown in the figure. FIG. 9 shows the formation of the magnetic lines of force of the magnetic rollers that consist of a plurality of sets of these magnets.

Also in the above-mentioned magnet rotating magnetic roller according to the present invention,
The diagonal magnetization is effective in any case, whether it is only the N pole, only the 11-1:S pole, or both magnetic poles. In the case of oblique magnetization of both magnetic poles, either the intersecting arrangement shown in FIG. 4 or the parallel arrangement shown in FIG. 8 is possible, but particularly preferable results were obtained with the former. In addition, if the magnetization angle α is set too large in any case, the ears will become lower, and the developing conditions will become stricter.
°, preferably 20° to 45°. α1 defined in the same way as in FIG. Of course, α does not have to be the same. Furthermore, only one of the magnets may be obliquely magnetized.

In addition, in this method of alternately arranging diagonally magnetized magnets and NSs, the developer reciprocates in the direction perpendicular to its progress, so toner clogging and clogging can be prevented more effectively than in the first embodiment (Fig. 6, etc.). can do.

As described above in detail, in the developing device of the present invention,
By obliquely magnetizing the magnetic poles that generate magnetic force so that the lines of magnetic force intersect or form a flat iK, and by forming the lines of magnetic force at an angle with respect to the developer transport direction, development in the developer thickness regulating section is achieved. By preventing agglomeration of the developer and eliminating problems caused by toner clogging, uniform copied images can be obtained even in the direction transverse to the developer conveyance direction.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a developing device using a magnetic brush, FIG. 2 is a diagram schematically showing developer clogging in the developer regulating section of a conventional developing device, and FIGS. 3 and 4 are in accordance with the present invention. FIGS. 5 and 6 are a perspective view, a side view, a front view, and a sectional view of a developer regulating portion according to the present invention in a magnet surface-shaped developing device, and FIGS.
The figures are a magnetic pole arrangement diagram and a magnetic force line formation diagram according to the present invention in a magnet rotation type developing device. 12, 22, 32, 42...developer holding member (
Sleeve), 16, 26, 36...Standing control plate, 24S, 24N...Sub magnetic pole, 24S, 24N, 33S, 33N, 4
3 S,, 43N...Magnet. Agent Yoshimi Kuwahara $ Figure 4 (A) (8) Hayabusa (A) Figure 7 (E3) Procedural amendment 111',,! Japanese Imperial Year 3JJ231: IRff'+li
Director Kazuo Wakasugi 1 Matters A'1 lj: Showa Kaku I1' - Patent Application No. 1535 υ2 Name of the invention; Nishi-Shinjuku 1, Shinjuku-ku, Tokyo, 26th, 2nd name
(+271 Roku Konishi Photo 2 [Nobuhiko Motomoto 4 agent for representative director of Kaikan Co., Ltd. 191) -: Tokyo 1-l 11! f middle cut II
I] 1; 1r 5 Supplement 11 - Order H A.1 Voluntary amendment 6, "Claims" column in the specification subject to amendment Drawings in the "Detailed description of the invention" column in the description 7. Contents of amendment (1) The scope of claims will be corrected as shown in the attached sheet. (2) In the additional line of page 5 of the statement box, the phrase ``In the developer regulation area on the sleeve'' was replaced with ``A magnet magnetized with steel is placed in the developer regulation area relative to the rotation axis of the sleeve. ” he corrected. (3) Delete "The lines of magnetic force of the magnet are formed obliquely with respect to the direction of rotation of the sleeve" from the first line to the second line of page 6. (4) Page 7, lines 15 to 16 [As shown, in the direction of movement of the developer layer, in other words, in the direction of the arrow.”
The statement has been corrected to read, ``Put it against the developer support surface of the sleeve η, in other words, do not pierce the rotating shaft of the sleeve η.'' (5) Delete "in the direction of the arrow in Figure 6" in the first line of page 8. (6) Page 8, line 1, next to ``change'' [This situation is shown in Figure 6. If a stably magnetized magnet is placed near the developer regulating plate 26 as shown in FIG. 5, the direction of the lines of magnetic force will change between 24N and 248. As a result, the magnetic brush ear changes its shape from being tilted to one side to being tilted to the other side as it passes through these magnet ears, and the developer is distributed approximately as shown by the arrow in Figure 6. Do the moves. ”2 join. (In addition, after “Moyoi” on page 11, page 10 of the same document, add “Also, the ear standing regulation plate 36 may be made of magnetic material.”) Warning (8) Amend Figure 7 (B) as shown in the attached sheet. Attachment Claim 1: A developing device in which a regulating member is provided for conveying developer while adsorbing it onto a rotating sleeve having a built-in magnetic force generating portion, and developing a fixed amount of developer on an electrostatic latent image surface. 1. The developing device according to claim 1, wherein a magnet is disposed in the developer regulation area in a manner that is magnetized with respect to the rotating shaft of the rotary sleeve. Developing device according to range 1. Line 7 (δ

Claims (1)

[Claims] A developing device is provided with a regulating member for conveying developer while adsorbing it onto a rotating sleeve having a built-in magnetic force generator, and developing a fixed amount of developer on an electrostatic latent image surface.
A developing device characterized in that lines of magnetic force of the magnetic force generating section in a developer regulating area on the rotary sleeve are inclined with respect to the rotational direction of the rotary sleeve and formed at a temperature of .degree.