JP3487962B2 - Manufacturing method of electrophotographic photosensitive drum - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to a process for the preparation of electronic photosensitive drum.

[0002]

BACKGROUND ART Conventionally, an electrophotographic photosensitive drum to precisely rotate within such printers (hereinafter, simply drum gutter
There is a case. ) In the field of producing, connecting the rotation center axis relative to the outer diameter of the drum <br/> member, fitted to both ends of the drum members, the center of the shaft hole of the two flanges are bonded It is necessary to manufacture a drum with a center line as close as possible and with reduced run-out.

[0003] In this case, conventionally, first, the drum member, or subjected to ironing the extruded tube of aluminum, or a drawn tube is pulled out of the extruded tube, further cutting the drawn tube, the machining such as polishing was added, as a basic Increase the accuracy of. On the other hand, the flange is obtained by injection molding of a resin, or after molding a metal such as aluminum by die-casting, and then performing a cutting process to improve the accuracy of the fitting portion. also the fitting outer diameter of the flange is greater than the fitting inner diameter of the drum member as improved methods for runout, a method of forcibly press-fitting the flange into the drum member came taken.

[0004]

However, since each member requires high dimensional accuracy, there is a problem that the improvement of the rotational runout by such a method leads to a large cost increase. Moreover, since the two members are manufactured independently and then fitted and adhered to each other, there is a limit to improvement in accuracy after fitting and adhesion.

The inventor of the present invention first provided a gap in the fitting portion of two members for the purpose of manufacturing the electrophotographic photosensitive drum as a measure for improving the accuracy of the above-mentioned fitting and bonding, and applied an adhesive to the drum portion. After the flange is inserted into the material, a method of holding the relative position of the adhesive so as not to move until the adhesive is substantially cured (see Japanese Patent Application Laid-Open No. 4-251279) or a quick-hardening adhesive. Method in which an elastic adhesive is used in combination (JP-A-6-2822)
No. 04), etc. have been proposed.

However, in the former case, it is necessary to avoid vibration and displacement during curing of the adhesive and it is necessary to take some time in the bonding process. In the latter case, heating is required to cure the elastic adhesive. , If the fast-curing adhesive that has already hardened is inelastic, the thermal expansion of the flange and the adhesive is larger than that of the aluminum base that is the drum member, so that the above-mentioned concentricity that was maintained during fitting was It could have been damaged.

Further, when the drum member and the flange having a large difference in thermal expansion coefficient between the materials are fitted and adhered to each other, and a heating process is performed, deformation due to thermal expansion causes a material having a low thermal deformation temperature. There was a technical problem in that creep was caused in the steel and it remained as a permanent strain after cooling, resulting in an increase in rotational runout.

[0008]

As a result of earnest research to solve the above-mentioned problems, the present inventor has provided a gap in the fitting portion between the drum member and the flange, and the rotation of the flange is prevented by rotating the drum member in the gap. The present invention has been completed by discovering that the above-mentioned problem can be solved by introducing an elastic piece capable of fixing the both, applying an elastic adhesive, and then fitting the two together.

That is, an object of the present invention is to provide a method for manufacturing an electrophotographic photosensitive drum, which can be applied to the electrophotographic photosensitive layer after the drum member and the flange have been fitted and adhered to each other in advance. It is a thing. It is another object of the present invention to provide a method for producing a drum which does not impair the rotation accuracy due to thermal expansion, thermal deformation, etc. when the electrophotographic photosensitive layer is heated and dried after being applied. Furthermore, the present invention can easily and accurately perform the photosensitive layer of the electrophotographic photosensitive drum and the shaft for driving the photosensitive drum without using a conductive member such as a conductive elastic spring such as phosphor bronze that is difficult to assemble. It is an object of the present invention to provide an inexpensive electrophotographic photosensitive drum manufacturing method capable of ensuring continuity between the electrophotographic photosensitive drum and the adhesive curing step and the photosensitive layer coating film drying step in common. Is.

Further , according to the present invention, an end portion of the drum member and a flange, which is a support member having an outer diameter of a fitting portion smaller than an inner diameter of the end portion of the drum member, are attached to the inner diameter of the end portion of the drum member. An elastic piece having a wall thickness larger than 1/2 of the outer diameter difference of the fitting portion of the flange is adhered and fixed to the flange fitting portion at appropriate intervals in the circumferential direction, and then an elastic adhesive is applied. The present invention is directed to a method of manufacturing an electrophotographic photosensitive drum, which comprises fitting and press-fitting, then applying a coating film required for the electrophotographic photosensitive member to the drum member, and heating and drying.

[0011] The following is a description of the present onset Akira in detail. The drum member in the present invention is not particularly limited, but examples thereof include a pipe material having a not so high accuracy, an aluminum extruded pipe, a drawn pipe, a resin pipe, a paper pipe, etc., and an electrophotographic photosensitive drum etc. that has been used once and reproduced. To be done. As the flange as the supporting member, a resin-made one, a metal-made one, or the like, which is given conductivity by a ground terminal or the like and has a heat deformation temperature of 100 ° C. or more, can be applied.

As a method of applying the photosensitive layer to the drum member in the present invention, a method of spin-coating while holding the drum member horizontally, such as spray coating, nozzle coating, curtain coating, can be preferably used. As the elastic piece that is adhesively fixed to the flange, a conductive rubber sheet piece is preferable. At this time, it is preferable to use a conductive adhesive as the attaching adhesive for fixing the adhesive.

The thickness of the elastic piece needs to be thicker than 1/2 of the difference between the inner diameter of the end of the drum member and the outer diameter of the fitting portion of the flange, and preferably 1/2 of the difference. ~ 1 times the thickness. The concrete difference is usually 0.9 to 4.0.
mm is about 30 to 200 μm from 1/2 of this difference
It is preferably thick. After the elastic adhesive is cured and as the elastic modulus of the conductive rubber, it is preferable that the elastic rubber has a somewhat soft rubber elasticity, and the Young's modulus is 5 × 10 ^{5 to} 5 × 1.
0 ⁶ N / m ² is preferred. If the elastic modulus is too large, the thermal expansion that occurs during the heating process may not be absorbed and the conductive flange may creep.If the elastic modulus is too small, spin coating before the elastic adhesive after curing is cured At times, since the contact area between the inner surface of the work and the flange fitting portion is small, it is chucked by the flange hole, and it becomes impossible to accurately transfer the drum driving force transmitted from the rotating shaft to the outer surface of the work, which is the drum member. there is a possibility.

As the elastic adhesive applied to the flange before fitting, known adhesives having elasticity such as silicone type and epoxy modified silicone type are preferable. As the elastic body, a material that loses elasticity when heated and easily causes creep due to stress generated by expansion is not preferable, and a conductive elastic body such as a conductive silicone rubber sheet is preferable.

The rubber sheet pieces are bonded and fixed at intervals in the circumferential direction of the flange, but they are arranged at equal intervals, and in that case, the area ratio of the portion covered with the sheet piece and the other portion is 1: 4 to. A range of 4: 1 is preferred. The above-mentioned elastic adhesive is applied to a portion which is not covered with the sheet piece, and fitted and adhered.

When the flange is made of a resin that is made conductive by a ground terminal or the like, a volume change due to crystallization, which is a kind of thermal deformation, occurs in the heating process after fitting,
The rotational run-out accuracy around the flange hole before the heating step may be significantly impaired after the heating step. Therefore,
It is desirable to perform sufficient heat treatment before mating to advance crystallization.

When a polyethylene terephthalate resin which is made conductive with conductive carbon is used for the flange, there is a relation between the heat treatment temperature for crystallization and the decrease in accuracy after heat processing, and at 120 to 170 ° C. for 1 hour or more, Preferably 15
By using a material that has been subjected to a heat treatment at 0 to 165 ° C. for 1 to 5 hours, it is possible to suppress the rotational runout change before and after the drying step after coating, which is usually performed at 100 to 130 ° C., to 30 μm or less.

Next, the bonding operation will be concretely described with reference to the accompanying drawings. FIG. 1 shows a flange and an embodiment of the present invention.
It is a perspective view of a drum member. In the figure, 1 is a flange body,
Reference numeral 2 is a flange hole portion, 3 is a flange fitting portion, and 4 is a conductive elastic sheet piece that is adhesively fixed to the flange. FIG. 2 is a schematic view of the bonding device. In the figure, 6 is a work which is a drum member.

First, as shown in FIG. 1, the flange 1 in which the conductive elastic sheet piece 4 is bonded and fixed to the fitting portion 3 of the flange body 1 and the inner expansion collet chuck 7 and the flange hole 2 in the bonding device of FIG. Insert and hold in to set. The V block 8 and the flange fitting system 14 are installed on the table 5 shown in FIG. 2, and the work 6 is placed on the V block 8 and fixed by the presser 15. An inner expansion collet chuck 7 is rotatably fixed to a bearing 9 at the base thereof in the flange fitting system.
Gear 10 is set at the end, and timing belt 11
And is connected to the motor 12. The discharge port of the adhesive supply dispenser 13 is close to the flange body 1.

The flange body 1 is slowly rotated by the motor 12, and the adhesive is supplied from the dispenser 13 to the portion where the conductive elastic sheet piece 4 is not fixed by adhesion. When the supply of the adhesive is finished, the rotation of the flange 1 is stopped, the flange fitting system 14 on the base 5 is pushed forward by the force of an air cylinder (not shown), etc. 3 is pressed into the end opening of the work 6.

After that, the presser 15 is removed, the V block 8 is lowered, the work 6 having the flange fitted thereto is removed from the bonding device, and set in the coating device. Although the example in which the bonding device and the coating device are different devices has been described above, it is also possible to devise the device so that the flange bonding and the next coating can be continuously performed by the same device. For a drum with poor accuracy in which the flanges are fitted and bonded by such a method, the outer diameter accuracy with the shaft hole of the flange as the central axis is corrected by the method previously proposed by the present inventor (Japanese Patent Application No. 6-259429). In the case of performing, the precision of the flange fitting portion does not need to be extremely high as in the conventional case, and thus the cost is low .

[0022]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples as long as the gist thereof is not exceeded. Example 1 Fitting part outer diameter 25.1 mmφ, width 10 mm, hole diameter 6.0 m
mφ conductive polyethylene terephthalate resin flange (made by Asahi Polyslide Company, trade name Elena) with a 1.0 mm thick piece of conductive silicone rubber sheet (made by Irumagawa Rubber Co., Ltd.) at the fitting part using an elastic adhesive (cemedine Company E
P001) was thinly applied and fixed by adhesion. The rubber sheet piece was 6 mm × 8 mm, and the fitting tip portion was tapered.
After adhering the rubber sheet, the flange was heat-treated at 160 ° C. for 2 hours in an oven.

Aluminum extruded tube with an outer diameter of 29.50 mm
A Φ, an inner diameter of 27.00 mm Φ, and a length of 260 mm were prepared, set on the V block 8, and lightly fixed with the presser foot 15. After heat treatment, use 2 flanges to expand the collet chuck 7,
7 rpm, 16 rpm using motors 12 and 12
To rotate the flange. The ejection time of the dispenser 13 was calculated in advance from the set angle, the size of the rubber sheet piece, and the rotation speed, and the adhesive was ejected mainly where the rubber sheet piece was not adhered. After the discharge, the rotation of the flange was stopped, the flange fitting system 14 was advanced by an air cylinder, and the flange was press-fitted into the extruded pipe. The whole gripping system was released, the extruded tube was taken out, and set on the outer diameter correction device to correct the outer diameter accuracy.

There was no abnormality in the flange fitting, and the total shake before correction measured by the laser length measuring machine was 150 μm, but after correction it became 30 μm. Then, after coating with a conductive layer, a blocking layer, a charge generation layer, and a charge transfer layer, 1
It was dried at 30 ° C. for 30 minutes. When the total shake after drying was measured by the same laser length measuring device, it was 40 μm.

Example 2 A rubber sheet piece was bonded and fixed to a flange in the same manner as in Example 1, then set in a flange bonding apparatus without any heat treatment and press-fitted into an extruded tube. The outer diameter was corrected in the same manner as in Example 1. The total shake before and after correction is 130 μm and 20 μm, respectively.
Met. After applying the same four layers as in Example 1, drying was performed under the same conditions. The total shake after drying was 120 μm.

Example 3 A mirror cut tube having an outer diameter of 30.0 mmφ and an inner diameter of a brazing part of 28.5 mmφ was fitted with an outer diameter of 26.6 mmφ and a width of 10 mm.
After the conductive silicone rubber sheet piece was bonded to the same conductive flange as in Example 1 having a hole diameter of 6 mmφ, the flange was fitted and bonded to the cutting pipe. Then, the charge generation layer and the charge transfer layer were applied by nozzle ejection and blade smoothing, and dried. When the flange was fitted and adhered to the cutting tube, the flange hole was held and rotated by the inner expanding collet chuck, and the total runout was measured, resulting in 40 μm. The same measurement after coating and drying revealed a value of 45 μm.

Comparative Example In the same cutting pipe, a flange having the same conditions except that the outer diameter of the fitting portion was changed to 28.6φ was press-fitted without a conductive silicone rubber piece, and a charge generation layer was formed as in the example. Charge transfer layer,
It was applied and dried. Similarly, as a result of measuring the total shake, the value before coating was 30 μm, while the value after drying was 100 μm.

[0028]

According to the present invention, to produce fitted flange and an electrophotographic photosensitive drum <br/> member and the drum rotation supporting member, an electrophotographic photosensitive drum formed by adhering very advantageously The resulting drum has high concentricity accuracy. Further , according to the present invention, the electrophotographic photosensitive drum can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a perspective view illustrating an embodiment of the present invention.

FIG. 2 is a schematic view of an example of a bonding device used for carrying out the present invention.

[Explanation of symbols]

1 Flange body 2 Flange hole 3 Flange fitting 4 Conductive elastic piece 6 work

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-88595 (JP, A) JP-A-1-319782 (JP, A) JP-A-6-282204 (JP, A) JP-A-6- 256534 (JP, A) JP-A-4-106578 (JP, A) JP-A-7-13468 (JP, A) JP-A-5-150462 (JP, A) Actual development 1-136959 (JP, U) 59-116629 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 21/00 350 G03G 15/00 550 B29C 65/48 B29L 31:32

Claims (3)

(57) [Claims] 1. A end of the electrophotographic photosensitive drum member and the electrostatic
The flange and a support member having a diameter smaller than the fitting the outer diameter of the end portion of the slave photosensitive drum member, said electrophotographic
An elastic piece having a wall thickness larger than ½ of the difference between the inner diameter of the end portion of the photosensitive drum member and the outer diameter of the fitting portion of the flange is provided at the flange fitting portion at appropriate intervals in the circumferential direction. after bonded, fitting by applying an elastic adhesive, press-fitted, and then the electrostatic
A method for producing an electrophotographic photosensitive drum, which comprises applying a coating film required for an electrophotographic photosensitive member to a subphotographic photosensitive drum member, followed by heating and drying. 2. The thickness of the elastic body is 1 / the difference between the inner diameter of the end portion of the electrophotographic photosensitive drum member and the outer diameter of the fitting portion of the flange.
The production method according to claim 1, wherein the production method is 2 to 1. 3. A method according to claim 1 or 2, wherein the elastic body piece is conductive silicone rubber sheet pieces.