JPS60142369A - Developing device of electrophotographic copying machine - Google Patents

Abstract

PURPOSE:To forming ruggedness in an optional shape, provide developer conveying force, and use a rigid nonmagnetic sleeve by forming a nonmagnetic sleeve of stainless steel by etching, etc. CONSTITUTION:A magnet roller on which a pattern is drawn is dipped in an etching solution, e.g. ferric chloride solution. When a linear part B is drawn in ink and etched, a part A in a diamond shape is dipped to form a recessed part and line parts form projection parts. The depth of the projections and recesses is adjusted according to the density of the solution, dipping treatment time, temperature, pressure, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developing device for an electrophotographic copying machine, and particularly to a sleeve for a mag roll thereof.

[Prior art]

An electrophotographic copying machine applies toner to an electrical latent image formed on the surface of a photosensitive drum, develops it, transfers it to paper, and then heats and fixes it to make a copy. In this case, in order to obtain a good quality copy with uniform density, it is necessary to uniformly supply toner to the electrical latent image regardless of its physical location.

FIG. 1 shows a conventional developing device. In the figure, reference numeral 1 denotes a toner cartridge, from which toner is supplied via a dispense roller 2 into a developing device 3. This toner is mixed with a carrier to form a developer 8, which is mixed by a blender 4, frictionally charged by "τ", and supplied to a mag 1 call 6 by a paddle wheel 5.

The developer on the mag roll 6 is adjusted to a substantially uniform thickness by the trimmer 7, toner is attached to the latent image on the photosensitive drum 9, and the latent image is developed.

In this case, the mag roll 6 includes, for example, a cylindrical magnet 10 made of ferrite, a nonmagnetic sleeve 11, and a shaft 12.
has. The non-magnetic sleeve 11 is made of a non-magnetic material such as 8β, and has irregularities formed on its surface to facilitate conveyance of the developer.

These irregularities were formed by Zand blasting, or as shown in Figure 2 (by extruding or drawing aluminum to form single letter-shaped irregularities, by other means such as knurling, or by thermal spraying of stainless steel. Figure 3). is a cross-sectional view of the mag roll, and the unevenness of the non-magnetic sleeve is omitted.

Such processing means can be applied when the material of the non-magnetic sleeve is a relatively soft material such as /11. The drawback is that the surface sprayed shape cannot be freely determined, the uneven shape is only linear, and the depth of the unevenness can only be about 80 μm.

However, recently, it has become necessary to use paper for drawings that is larger than the A3 84-size paper (for example, A2 or larger), and the size of the photosensitive drum has also increased due to the dirt. , and the length of the macrol becomes large.

When the length of the mag roll becomes large like this, if the non-magnetic sleeve is made of AA as in the past, it is soft and lacks mechanical strength, so a hard non-magnetic sleeve such as stainless steel must be used. No.

However, since stainless steel is hard, even if the surface is sandblasted, only grooves with a depth of about 8 to 10 μm can be obtained, which is not sufficient surface roughness, and the required surface roughness is 0, 2 to 10 μm.
Since it is not possible to obtain grooves with a depth of about 0.3 mm, there is a problem in that the developer conveying force is insufficient and it is difficult to provide copies of poor quality.

In addition, in the case of stainless steel, processing by drawing is also difficult in terms of manufacturing.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a developing device for an electrophotographic copying machine equipped with a non-magnetic sleeve having grooves formed on its surface by etching so that a hard non-magnetic sleeve such as stainless steel can be used. It is in.

[Structure of the invention]

In order to achieve such an object, in the present invention, a non-magnetic sleeve such as stainless steel is processed by etching to form irregularities of an arbitrary shape, thereby imparting developer conveying power.

Etching processing can easily form irregularities in a shape suitable for developer transport, so it is not only possible to provide high-quality copies, but also to make hard materials such as stainless steel. Since irregularities of an appropriate shape and depth can be easily formed on the surface, it is possible to provide high-quality copies even on large sheets of paper.

〔Example〕

An embodiment of the present invention will be described based on FIG.

In FIG. 4, 20 is a mag roll, which includes a stainless steel mag roll sleeve 21 and a cylindrical maknet 23.
The surface of the mag roll sleeve 21 is an etched surface 22 which will be described later. Magroll 20 is
It functions similarly to the Mac I call 6 shown in FIG. 1, and is placed within the developing unit.

Etching of the magroll sleeve 21 is performed as follows.

First, +ff should be processed on the surface of the Magroll sleeve.
Draw with Samwo ink. In this case, the Magroll sleeve with the pattern drawn on the convex portions with ink is immersed in etching solution /& (ferric chloride solution) for about 60 minutes.

Therefore, if the linear part B shown in FIG. 4(b) is drawn with ink and etched, the diamond-shaped part A will be digested and become four parts, and the line part will become a convex part, resulting in diamond-shaped etching. .

The depth of this unevenness is preferably about 0.05 to 0.5 mm,
This depth can be adjusted by adjusting the concentration of the solution, the immersion treatment time, temperature and pressure, etc.

Of course, the pattern on the surface may be, for example, round or square as shown in FIGS. 5(a) and 5(b), or an etched pattern in the form of a single letter or any other appropriate pattern may be used.

In the present invention, even if the magroll sleeve is made of stainless steel, it is possible to easily form irregularities of any shape and depth on its surface. Since it is possible to maintain good 1i1 feeding performance and to optimize the spiked state of the developer, it is possible to provide high-quality copies.

In the above description, an example was explained in which stainless steel was used as the magroll sleeve, but the material is not limited to stainless steel as long as its mechanical strength is satisfactory, and Aβ metal can also be used. Even when other materials are used, it is possible to easily form irregularities of an appropriate pattern and depth by etching the surface. Therefore, the cost is low, mass production is possible, and mag rolls having the desired surface shape can be provided for any material.As a result, high-quality copies can be provided at low cost even when using large-sized paper. be able to.

〔Effect of the invention〕

According to the present invention, even when a hard material such as stainless steel with high mechanical strength is used for the mag roll sleeve, the surface thereof has a plurality of shapes suitable for conveying the developer and has an appropriate depth. Since a mag roll with an uneven surface formed by etching is used, it is possible to make high-quality copies even in a copying machine for large sheets of paper.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a developing device, FIG. 2 is a block diagram of a conventional mag roll, FIG. 4 is a mag roll used in the present invention, and FIG. 5 is an example of a pattern of a mag roll sleeve. ■-Toner cartridge 2-Dispense roller 3-Developer 4-Blesseder 5-Paddle wheel 6-Magerol 7-Trimmer 8-Developer 9-Photosensitive drum 10-Cylindrical magnet 11-Nonmagnetic sleeve 12-Shaft 20- Mag roll 21 - Mag roll sleeve 22 - Etched surface 23 - Cylindrical magnet Patent applicant Fuji Xerox Co., Ltd. Representative patent attorney Akira Yamatani Sakae Procedural amendment (method) April 2, 1980 2, Title of invention Electronic photograph Developing device 3 of a copying machine and its relationship to the case to be amended Patent applicant address: 3-3-5 Akasaka, Minato-ku, Tokyo Name: Fuji Xerox Co., Ltd. Representative Yotabe Kobayashi 4 Agent address: Chiyoda-ku, Tokyo Kanda Awajicho 1-19-8-6,
? The number of inventions increases due to lli positive No 7,? ili
Positive object Field formula for a brief explanation of drawings in the specification l't・
1) fX Correction details 1, "Figure 1, Figure 4, page 8, line 3 of the specification" is corrected to read, "Figure 3 is a cross-sectional view of the mag roll, Figure 4."that's all

Claims (1)

[Claims] In an electrophotographic copying machine that is equipped with a photoreceptor on which a latent image is formed and a mag roll that supplies developer to the latent image, the mag roll is formed into a cylindrical non-magnetic sleeve whose surface has been roughened by an etching means. Alternatively, a developing device for an electrophotographic copying machine characterized by being arranged outside a square magnet.