JPH05210290A - Developing device for image forming device - Google Patents

Abstract

PURPOSE:To prevent the overflow of a toner from the side part of a developing device by forming and disposing a sealing member superposed with a sponge-like elastic member and a porous sheet between the outer periphery of a developing sleeve and the end edge in the side wall part of a developer container. CONSTITUTION:The sleeve 2 is mounted into a recessed part formed in the side wall 4 of the developing device. The sealing member 1 is mounted in the spacing part between both. The sealing member 1 consists of an inner member consisting of such a material which is low in friction and does not allow the leakage of the toner on the side in sliding contact with the sleeve 2 and an outer member for stably pressing the inner member to the sleeve 2 by maintaining elasticity over a long period of time. Fluoropores which consist of 'TeflonR' formed porous, etc., are suitable as the inner member. Such a material which maintains the elasticity over a long period of time is suitable as the outer member on the side facing the container side end edge of the developing device. Polyurethane, etc., which are formed like sponge by expanding are utilizable as such material.

Description

Detailed Description of the Invention

[0001]

[Object of the Invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus utilizing an electrostatic transfer process, such as an electrostatic copying machine and a printer.
In particular, it relates to the developing device.

[0002]

2. Description of the Related Art In the developing device of the known image forming apparatus as described above, a cylindrical toner holding member (called a sleeve) made of a non-magnetic material is rotated inside a container for containing toner. The sleeve is freely arranged, toner is attached to the sleeve, and the toner is conveyed to a developing portion where the sleeve and the image carrier face each other, and the toner is attached to the electrostatic latent image on the side of the image carrier to form a toner image. Are usually configured to form

Due to such a structure, the outer periphery of the sleeve in the vicinity of both ends and the edge portion of the developing device container facing the sleeve cannot be in close contact with each other, and toner is prevented from escaping from this gap. Therefore, it is necessary to dispose a seal member in this portion.

FIG. 4 is a perspective view showing the structure of such a seal member. The felt 21 made of fluorocarbon Nomex (trade name) is provided on the surface of the double-sided tape 22 which is rubbed against the sleeve, and the opposite surface is provided on the opposite surface. A wool felt 23 is bonded and configured.

A sleeve 25 is disposed in a substantially semi-circular recess 24 'formed in the side wall 24 of the developing device, as shown in FIG. 5, and the seal member 20 is provided in the gap between the two, and the total thickness of the toner is adjusted. Filling arrangement is performed even to the blade 26 to be regulated.

[0006] However, in the seal member having such a structure, a gap is likely to occur because the thickness of the felt material is varied, and since the seal member is attached to a narrow place, the application method is likely to vary. Therefore, there is a problem that the sealing action is bad, the elasticity of the felt deteriorates due to long-term use, and toner leaks, which contaminates various parts inside the device and toner adheres to the drive gear to cause pitch unevenness. there were.

The present invention has been made to cope with such a situation, in which a sponge-like elastic member and a porous sheet having a smooth surface are superposed and molded into the shape of the above-mentioned gap portion. An object of the present invention is to provide a developing device which is provided with a sealing mechanism that does not deteriorate in characteristics even when used for a long period of time and can always perform a good sealing action.

[0008]

[Constitution of the invention]

In order to achieve the above-mentioned object, the present invention comprises a developer container for containing toner and a developing sleeve supported near the side wall of the container. In the developing device, the outer circumference of the sleeve,
A sealing member made of a porous sheet having a smooth surface that rubs against the sleeve and a sponge-like elastic material that is superposed on the porous sheet is formed and disposed between the end of the side wall portion and the edge of the side wall opposite to the side edge. It is characterized by becoming.

With this configuration, even in the case of fine toner, it is possible to stably prevent the toner from leaking out of the developing device for a long period of time.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a sleeve 2 is mounted in a recess formed in a side wall 4 of a developing device, and a seal member 1 is provided in a gap between the two.
FIG. 3 is a perspective view showing one end portion of the mounted device. A magnet is provided inside the sleeve, and reference numeral 3 is a regulation blade for regulating the toner on the sleeve, 4 is a container of the developing device, 5 is toner, and 6 is a spacer for maintaining the distance between the regulation blade and the sleeve. Shall be shown.

FIG. 2 is a perspective view of the seal member 1. The inner member 1a made of a material having a small friction and preventing toner leakage and the side wall of the container which maintains the elasticity for a long period of time is the side that rubs against the sleeve. And an outer member 1b for stably contacting the inner member 1a with the sleeve 2.

As the inner member 1a, fluoropore (Trade name: Sumitomo Electric Co., Ltd.) or Gore-Tex (Trade name: Dow Chemical Co.) made of Teflon is suitable. Since these materials are Teflon, they have good slidability with respect to the sleeve made of aluminum, stainless steel, etc. By making this into a sponge shape, it is possible to give elasticity, so that the adhesion to the sleeve surface is improved. Good.

The outer member 1b on the side facing the developing device container side edge is preferably made of a material that maintains elasticity over a long period of time. Examples of such materials include polyurethane, EPDM, chloroprene rubber, and silicone rubber. It is also possible to use a sponge-like foam made by foaming. In particular, a sponge based on polyurethane or silicone rubber is suitable because it has a small amount of substance exuding from the inside and the exuding substance does not adversely affect the developer.

The thickness of the inner member 1a is 0.1-2.
It only needs to have a thickness of about 0 mm. Also, the outer member 1b is 6
It is suitable that the mesh is 0 to 150 mesh and the thickness is about 1 to 5 mm.

It is well known that sponges include open cells and closed cells, but in the case of the outer member, closed cells are preferable for maintaining elasticity over a long period of time. Since this one has a high hardness, which one to use may be appropriately selected depending on the condition. Further, even in the case of continuous cells, if the thickness thereof is set to 3 to 5 mm or more, it is possible to avoid the situation that the toner is leached out.

In order to improve the image quality in recent years, the particle size is 4-8.
Fine particles of about μm have come to be used, and such fine toner easily leaks at various parts inside the image forming apparatus, but by using the seal member as described above, It is possible to minimize toner leakage from between the container edge and the sleeve.

FIG. 3 is a perspective view showing another embodiment, in which an elastic blade is used to regulate the amount of toner attached to the sleeve and conveyed.

A blade 8 made of urethane rubber having a thickness of 1.0 mm, which abuts one edge on the surface of the sleeve 1, is attached to a sheet metal 7 attached with a screw 9 at a proper position in the developing device main body. is there.

The sealing member 1 is attached so as to extend from the recessed portion of the edge of the developing device container to the blade 8, and since the blade 8 moves slightly back and forth, the end portion thereof is indicated by reference numeral 10. , A porous polyurethane sheet is attached.

With this structure, it is possible to greatly reduce the escape of toner even in the developing device using the elastic regulating blade.

[0021]

As described above, according to the present invention, in a developing device provided with a developing sleeve internally provided, a porous material is provided between the sleeve and the edge portion of the side wall of the developing device facing the sleeve. By arranging a sealing member in which a Teflon resin made of a material and a sponge-like elastic material are laminated, it is possible to greatly reduce the leakage of toner, and it is possible to stably maintain this leakage prevention action for a long period of time. There is.

[Brief description of drawings]

FIG. 1 is a perspective view of an essential part showing an embodiment of the present invention,

FIG. 2 is a perspective view of a seal member,

FIG. 3 is a perspective view showing another embodiment,

FIG. 4 is an expanded view showing a configuration of a known seal member,

FIG. 5 is a perspective view showing a side wall portion of a developing device container;

FIG. 6 is a perspective view of a main part of a known developing device equipped with a seal member.

[Explanation of symbols]

 1, 20 sealing material 2 sleeve 3 regulating blade 4 developing device side wall 6 spacer 7 sheet metal 8 elastic blade.

[Procedure amendment]

[Submission date] January 6, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Title of invention

[Correction method] Change

[Correction content]

Title: Developing device for image forming apparatus

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Sato 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (1)

[Claims] 1. A developing device comprising a developer container for containing toner and a developing sleeve supported in proximity to a side wall of the container, wherein the sleeve outer periphery and the side wall end edge facing the outer periphery of the sleeve. A developing device for an image forming apparatus, in which a sealing member made of a porous sheet having a smooth surface that rubs against a sleeve and a sponge-like elastic material that is superposed on the sealing sheet is formed and disposed therebetween.