JPH03153270A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent image irregurality from occurring by providing splashing toner attraction means which are coaxial to a gap regulation member, which are provided to the both side surfaces of the gap regulation member so that the same polarities thereof are faced each other, which remove toner splashing to the circumference of the gap regulation member from the outside circumferential surface and which also attract the toner to the both side surfaces. CONSTITUTION:A pair of hollow disk-like magnets 17 and 18 which are coaxial to a pair of resin regulation members (the rollers) 16 and 16, which have an outside diameter (h) which is shorter than the outside diameters H of the respective rollers 16 and 16, which is provided to the both surfaces of the respective rollers 16 and 16 so that the N poles thereof are faced each other and which attract the toner splashing to the circumferences of the rollers 16 and 16 from a housing are provided. Therefore, the splashing toner is attracted by the both surfaces having high magnetic flux density and prevented from being attached on the outside circumferential surface by repulsive force between the magnets 17 and 18 having the same polarity. Thus, the outside circumferential surfaces of the rollers 16 and 16 are always clean and the irregularity or a lateral line is prevented from occurring on an image.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial Application Field The present invention relates to an image forming apparatus, and more specifically, the MR between the body wall of a photoreceptor drum and the body wall of a developing roller in a housing is This is about copying machines that are regulated by the law.

(B) Prior art As shown in FIG.
The gap between the drum and the developer 0, ie, the distance d between the drum and the developer (hereinafter referred to as the D-S distance) is normally maintained at 0. 2
It is regulated to ~0.5xm. The toner adhering to the photosensitive drum 2 is collected into the cleaning device 7 by the cleaning blade 3.

(c) Problem to be solved by the invention However, the toner scattered from inside the housing 4 is
Since the toner particles may adhere to the outer circumferential surface of the rollers 5 and 6, if this is left unattended, there is a risk that the adhered toner particles will aggregate and adhere to the outer circumferential surface of the rollers 5 and 6. As a result, the D-S distance may vary, causing unevenness in the image, such as horizontal stripes or striped patterns.

(d) Means for solving the problem and its operation This invention comprises a photoreceptor drum, a developing housing, and a device for adsorbing a one-component magnetic toner stored in the housing onto the photoreceptor drum. The developing roller is coaxial with the developing roller and contacts a position corresponding to a non-developing area outside the developing area on the photosensitive drum, and can regulate the gap between the photosensitive drum and the developing roller to a predetermined length. The gap regulating member is coaxial with the gap regulating member, and is provided on both sides of the gap regulating member so that the same polarity faces each other, and removes toner scattered around the gap regulating member from the outer peripheral surface of the gap regulating member. In addition, there is provided an image forming apparatus equipped with scattered toner suction means capable of suctioning toner on both sides. A developing roller that is coaxial with the developing roller and is in contact with a position corresponding to a non-developing area outside the developing area on the photosensitive drum to attract the photosensitive drum and the developing roller. The gap can be regulated to a predetermined length.
The inner wall surface corresponding to the gap regulating member on the body wall of the photoconductor drum and the coaxial annular region within the gap regulating member are provided so that the same polarities face each other, and the body wall of the photoconductor drum and the gap regulation member are provided so that the same polarities face each other. An image forming apparatus is provided that includes a scattered toner removing means capable of removing toner that enters a contact area with a battlement of a member.

That is, the present invention provides an image forming apparatus in which the D-S distance between the photosensitive drum and the developing roller is regulated by a gap regulating member. Disk-shaped magnets are arranged on both sides of the regulation i*tt so that the same polarity faces each other, so that toner can be removed on the outer peripheral surface of the gap regulation member by the repulsion between the magnets of the same polarity, and the toner is not scattered. The toner is attracted to both side surfaces with high magnetic flux density, and the toner is prevented from adhering to the outer peripheral surface.

Also, from another point of view, the coaxial annular region within the gap regulating member and the space between FJU! Magnets are arranged on the inner wall surface of the photoreceptor drum corresponding to the control member so that the same poles face each other, and the repulsive force between the same poles creates a contact area between the body wall of the photoreceptor drum and the body wall of the roller regulating member. This eliminates scattered toner and prevents toner from adhering to the outer peripheral surface.

(e) Examples The present invention will be described in detail below based on examples shown in the drawings. Note that this invention is not limited to this.

1 to 3, the copying machine includes a photoreceptor drum 11 and a magnetic-component toner (
A developing roller 13 for adsorbing toner (hereinafter referred to as toner) onto the body wall of the photoreceptor drum 11, and a position coaxial with the developing roller and corresponding to a non-developing area 15 outside the developing area 14 on the photoreceptor drum 11. The body wall of the photoreceptor drum 11 and the developing roller 1 are respectively provided.
A pair of resin regulating members (hereinafter referred to as rollers) 16.16 capable of regulating the gap d between the body walls of No. 3 to a predetermined length, and coaxial with each of the rollers 16 and 1B, and an outer diameter H of each roller 16°16. Each roller 16.16 has a shorter outer diameter h (h<H) and is provided on both sides of each roller 16.16 so that the N poles face each other.
A scattered toner suction means capable of sucking toner scattered from the housing 12 is provided around the housing 12.

Further, the scattered toner suction means is shown in FIGS. 1(sc) and (b).
As shown in the figure, a pair of hollow disk-shaped magnets 7°18
Consisting of

Since this embodiment has the above configuration, magnetic flux lines (12, to 12.) as shown in FIG. 3 are formed, and the roller 1
6. Magnet on the outer surface of 16! The scattered toner is removed by the repulsive force of 7.18. Therefore, the scattered toner (magnetic material) does not adhere to the outer peripheral surfaces of the rollers 16, 16, but adheres to the magnets 17 and 18 on both sides of the rollers, which have a high magnetic flux density.

As a result, the outer peripheral surfaces of the rollers 16, 16 can always be maintained in a clean state, and it is possible to prevent unevenness in the image and occurrence of adjacent stripes.

Further, FIG. 4.5 shows the inner wall surface corresponding to the pair of rollers 16.16 on the body wall of the photosensitive drum 11 and each roller 16,1.
6 shows a copying machine having a plurality of magnet pairs 20 and 21, each of which is provided in a coaxial annular region within 6 so that the north poles thereof face each other.

As a result, the photoreceptor drum l! A repulsive force acts between the magnet 20 on the side and the magnet 21 on the side of the rollers 16 and 16, and the toner that tries to enter the contact area (pressure contact position) M with the body wall of the photoreceptor drum 11 can be removed. Therefore,
The scattered toner adheres to both sides of the rollers 16.16.

At this time, the photoreceptor drum! If the magnet 20 on the photosensitive drum side is arranged closer to the pressure contact position M of the rollers 16 and 16 than the magnet 21 on the roller side, even if toner enters the pressure contact position M, It adheres to the side of the drum where the magnetic force is strong and can be collected by the cleaning section.

A similar effect can also be obtained by making the magnetic force of the magnet 20 on the drum side stronger than that on the roller side.

Furthermore, as shown in Figure 6, the roller 16 has the same polarity (N pole).
By disposing magnets 30 and 31 facing each other on both sides, and disposing a magnet 33 with an N pole for the pressure contact part M on the inner wall of the drum 11 corresponding to the position of the CFI 6, the pressure contact part M The amount of toner that enters can be further reduced.

(F) Effects of the Invention As described above, according to the present invention, in an image forming apparatus of the type in which the distance between D and S between the photoreceptor drum and the developing roller is regulated by the gap regulating member, the distance between the photosensitive drum and the developing roller is fixed on both sides of the gap regulating member. Disc-shaped magnets are arranged so that the same polarity faces each other, and the scattered toner is attracted to both sides with high magnetic flux density, and the repulsion between the magnets of the same polarity prevents toner from adhering to the outer peripheral surface. .

Further, from another perspective, magnets are provided in a coaxial annular region within the gap regulating member and on the inner wall surface of the photoreceptor drum corresponding to the gap regulating member so that the same poles face each other,
The repulsive force can remove toner that enters the contact area between the body wall of the photosensitive drum and the body wall of the roller regulating member, thereby making it possible to prevent toner from adhering to the outer circumferential surface of the gap regulating member. As a result, the outer circumferential surface of the roller can always be maintained in a clean state, and unevenness and horizontal streaks can be prevented from occurring in the image.

[Brief explanation of the drawing]

FIGS. 1(a) and (b) are a perspective view and an exploded perspective view of a main part showing an embodiment of the first invention of the present application, respectively, and FIGS. 2(a), (b), and (c) are FIG. 3 is a diagram showing the principle of the above embodiment, and FIG. 4 is a diagram showing an embodiment of the second invention of the present application. Explanatory diagram, FIG. 5 is a view taken along the line A-A in FIG. 4, and FIG. 6 is a second view of the present application.
FIG. 7.8 is an explanatory diagram of the main part configuration showing another embodiment of the invention, and FIG. 7.8 is an explanatory diagram of the configuration of a conventional example. ! ! ...Photosensitive drum, 12...Developing housing, 13...Developing roller, 14...Currently 1 m area, 15...
...Non-development area, 16.16...Colo, 17.18...Hollow disk-shaped magnet (scattered toner suction means), 20.21...Magnet pair ( (scattered toner removal means), 30.31... Magnet (scattered toner removal means). Figure 1 (a) Figure 2 (b) Figure 2 6 2 Figure (c) Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. A photosensitive drum, a developing housing, a developing roller for adsorbing the one-component magnetic toner stored in the housing onto the photosensitive drum, and a developing roller coaxially attached to the developing roller. a gap regulating member that comes into contact with a position corresponding to a non-developing area outside the developing area on the photoconductor drum and can regulate the gap between the photoconductor drum and the developing roller to a predetermined length; It is coaxial and is provided on both sides of the gap regulating member so that the same polarity faces each other, and can remove toner scattered around the gap regulating member from the outer peripheral surface of the gap regulating member, and can also attract toner to both sides. An image forming apparatus comprising a scattered toner suction means. 2. A photoreceptor drum, a developing roller for adsorbing the one-component magnetic toner stored in the developer housing onto the photoreceptor drum, and a portion coaxial with the developing roller and outside the development area on the photoreceptor drum. a gap regulating member that contacts a position corresponding to the non-developing area of the photoconductor drum and can regulate the gap between the photoconductor drum and the developing roller to a predetermined length; an inner wall surface corresponding to the gap regulation member of the photoconductor drum body wall; A scattered toner removal device is provided in a coaxial annular region within the gap regulating member so that the same polarities face each other, and is capable of eliminating toner that enters the interface area between the body wall of the photoconductor drum and the body wall of the gap regulating member. An image forming apparatus comprising means.