JP3922840B2 - Seamless belt molding apparatus and seamless belt manufacturing method using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seamless belt used in an electrophotographic copying machine, a laser printer, and the like. More specifically, the present invention relates to a seamless belt forming apparatus for intermediate transfer, paper conveyance, development, or fixing, and uses the same. The present invention relates to an improved seamless belt manufacturing method.
[0002]
[Prior art]
A conventional seamless belt molding apparatus is not shown, but a mold for centrifugally molding a seamless belt is fitted and supported on a cylindrical rotary holder, or a driving roller is fitted on a pair of drive shafts. The lower part of the outer peripheral surface of the mold is held in contact with the drive roller.
[0003]
Examples of related prior art documents of this type include JP-A-3-34817 and JP-A-10-226028.
[0004]
[Problems to be solved by the invention]
In the conventional seamless belt molding apparatus, the mold is fitted and supported on the cantilevered rotating holder as described above, so that the posture of the mold becomes unstable and irregular small vibrations are generated during rotation. The thickness accuracy on the peripheral wall of the belt could not be improved. In addition, when a mold is brought into contact with and supported by a plurality of drive rollers, variations in speed occur between the plurality of drive rollers due to variations in the dimensions of the sprockets and drive rollers used, which may cause the mold to move up and down or cause a slight slip. Will be invited. As a result, there is a problem that chattering occurs when the mold rotates, and the thickness accuracy of the seamless belt varies greatly.
[0005]
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is capable of suppressing the occurrence of chatter during rotation of a mold and effectively suppressing variation in the thickness accuracy of the seamless belt. And a method for producing a seamless belt using the same.
[0006]
[Means for Solving the Problems]
In the present invention, in order to achieve the above object, the liquid material is injected into a rotating cylindrical and horizontally long mold, the liquid material is uniformly leveled on the inner peripheral surface, and the rotating mold is heated from the surroundings. The seamless belt is centrifugally molded,
A pair of lids that are detachably fitted to both ends of the mold, a plurality of driving rollers that contact and support one lower side of the outer peripheral surface of each lid, and the other lower side of the outer peripheral surface of each lid A plurality of driven rollers that support and rotate as the mold rotates,
Applying matte black on the outer peripheral surface of the mold, the center of each lid as an inlet for liquid material,
A plurality of driven rollers can be slid horizontally and horizontally with respect to a plurality of driving rollers, and the outer peripheral surfaces of the plurality of driving rollers and the driven rollers are made of a heat-resistant elastic elastomer having a hardness of 30 ° to 90 ° H. Each is characterized by being coated .
In order to achieve the above object, the present invention is characterized in that a seamless belt is manufactured using the seamless belt molding apparatus according to claim 1.
[0007]
Here, as a constituent resin of the seamless belt in the claims, polyester resins such as PET, PBT, PEN, polyimide resins, polyamideimide resins, polyamide resins, fluororesins, polysulfone, polyethersulfone, Polycarbonate, aramid resin, polyetheretherketone and the like can be mentioned, and among these, PES having excellent creep resistance is preferable. The constituent resin of the seamless belt may be either thermosetting or thermoplastic, and is used after being dissolved in a solvent, but an appropriate one can be selected depending on the production method to be carried out.
[0008]
According to the present invention, the mold is rotated only by the driving roller driven on one side, and the driven roller is rotated following the rotation of the mold. As a result, the driving roller and the driven roller can be rotated at a fixed speed, and the occurrence of speed variations among the plurality of rollers can be suppressed or prevented. Also, because the mold is not supported by the driving roller and the driven roller and not supported by an unstable cantilevered rotating holder, the posture during rotation of the mold for manufacturing a cylindrical molded product such as a seamless belt Is stable.
[0009]
Further, since the elastic elastomer is excellent in heat resistance, it can be used continuously for a long time even if the mold is heated during molding. For example, when silicone rubber or fluororubber is used as the elastic elastomer, continuous use is possible without thermal degradation even at temperatures of 150 ° C. or higher. In addition, since silicone rubber has a small change in physical properties at high temperatures for a long time, the rotation of the mold is stabilized. Further, when the elastic elastomer has a vibration damping function, the elastic elastomer absorbs and attenuates the vibration of the rotating mold.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments.
As shown in FIGS. 1 and 2, the seamless belt molding apparatus according to the present embodiment includes a mold 2 for centrifugally molding the seamless belt 1, a drive device 4 for rotating the mold 2, and the drive device 4. It is comprised from the follower 9 which can contact / separate with respect.
[0011]
The mold 2 is formed in a horizontally long cylindrical shape using various metals, and a polymer material dissolved in a solvent or a liquid material made of a liquid curable material and a conductive filler is injected. The mold 2 has a smooth mirror finish, fluorine finish or silicone resin finish on the inner peripheral surface so that the seamless belt 1 can be easily removed, and a matte black (not shown) is applied to the rough outer peripheral surface. This black color efficiently absorbs heat from the external heater. Ring-shaped lids 3 are detachably fitted to both ends of the mold 2, and liquid material injection ports are perforated at the center of these lids 3.
[0012]
The drive device 4 includes various motors 5 and a drive shaft 6 that is rotated by the rotation of the motor 5, and drive rollers 7 are fitted to both ends of the drive shaft 6, respectively. The roller 7 contacts and supports the lower part of the outer peripheral surface of the lid 3 so as to be slidable. The outer peripheral surface of each drive roller 7 is a heat-resistant and cylindrical elastic elastomer 8, for example, silicone rubber, chloroprene rubber, fluorine rubber, etc. excellent in oil resistance, solvent resistance, chemical resistance, weather resistance, cold resistance, etc. The elastic elastomer 8 comes into contact with the lower part of the outer peripheral surface of the lid 3 and exhibits a damping function. The elastic elastomer 8 has a hardness of 90 ° H or less, preferably about 30 ° H to 90 ° H. This is because if it is less than 30 ° H, the compression set characteristics deteriorate, and if it exceeds 90 ° H, the compression load becomes too high.
[0013]
The driven device 9 includes a free driven shaft 10 that slides in the horizontal horizontal direction of the arrow (left and right in FIG. 1) with respect to the drive shaft 6, and driven rollers 11 are fitted to both ends of the driven shaft 10. The pair of driven rollers 11 contacts and supports the lower part of the outer peripheral surface of the lid 3 so as to be slidable. A cylindrical elastic elastomer 12 having a heat resistance and durability, such as silicone rubber, chloroprene rubber, or fluorine rubber, is endlessly covered on the outer peripheral surface of each driven roller 11, and the elastic elastomer 12 is provided at the lower portion of the outer peripheral surface of the lid 3. Operate vibration control function in contact. The hardness of the elastic elastomer 12 is the same as that of the elastic elastomer 8 of the drive roller 7.
[0014]
Next, the manufacturing method of the seamless belt using the said shaping | molding apparatus is explained in full detail. When forming the seamless belt 1, first, the driving device 4 is driven to rotate the horizontal mold 2, and a liquid material is injected into the injection port of the lid 3 of the mold 2 to inject the inner circumference of the mold 2. The liquid material is uniformly applied to the surface and leveled, and the external belt is heated from the surroundings to promote the reduction of the viscosity of the liquid material and the evaporation of the organic solvent, and the seamless belt 1 is centrifugally formed. At this time, if the solvent is rapidly evaporated and dried by simply heating with an external heater, the state of the outer peripheral surface of the seamless belt 1 deteriorates, so the temperature of the mold 2 is about 120 to 50 ° C. lower than the boiling point of the solvent. Then, the heating temperature is raised after the dry touch state is obtained, and the drying operation is completed.
[0015]
When the seamless belt 1 is centrifugally molded, the seamless belt 1 is air-cooled together with the mold 2. Then, due to the difference in thermal expansion coefficient between the mold 2 and the seamless belt 1, the seamless belt 1 naturally peels from the inner peripheral surface of the mold 2. When the mold 2 and the seamless belt 1 are in strong contact and cannot be peeled off naturally, the seamless belt 1 can be removed from the mold 2 by gradually peeling from the end of the seamless belt 1. After removing the seamless belt 1, the seamless belt 1 can be obtained by cutting the open ends of the seamless belt 1 to a predetermined length.
[0016]
According to the above configuration, the mold 2 is rotated only by the plurality of drive rollers 7 of the driving device 4 and the driven roller 11 is caused to follow the rotation of the mold 2, so that the gap between the plurality of drive rollers 7 and the driven roller 11 is There is no difference in speed. Therefore, it is possible to prevent the die 2 from moving up and down and minute slips with a simple configuration, and to generate chatter when the die 2 rotates, resulting in a large variation in the thickness accuracy of the seamless belt 1. It becomes possible to solve it reliably.
[0017]
Further, since the mold 2 is not fitted and supported on the cantilevered rotary holder, the posture stability of the mold 2 can be greatly expected. Therefore, irregular small vibration does not occur when the mold 2 rotates, and the thickness accuracy of the peripheral wall of the seamless belt 1 can be improved. Furthermore, since the drive device 4 and its power transmission member can be reduced as compared with the conventional case, simplification of the configuration, easy control, and the like can be greatly expected. Furthermore, since the driven device 9 slides toward and away from the drive device 4, the maintenance and replacement of the mold 2 are greatly facilitated, and the mold 2 having a different specification is easily dealt with. It becomes possible.
[0018]
Next, FIG. 3 shows another embodiment of the present invention. In this case, the central portion of the mold 2, the central portion of the driving roller 7 (driving shaft 6), and the central portion of the driven roller 11 ( Let the driven shaft 10) draw a triangle and the angle θ of the base angle on both sides of the lower part of the triangle is less than 45 ° (preferably less than 30 °), in other words, the angle of the apex angle of the triangle is greater than 90 °. Like to do. The other parts are the same as those in the above embodiment, and the description thereof is omitted.
In this embodiment, the same effect as that of the above embodiment can be expected, and the triangle 2 can be set to an obtuse triangle and the mold 2 can be set in a stable state between the driving roller 7 and the driven roller 11. It is clear that the seating is stable, the jumping of the mold 2, the minute slip, and the chattering of the mold 2 can be more effectively suppressed and prevented, and the thickness accuracy of the seamless belt 1 can be remarkably improved. is there.
[0019]
In the above embodiment, the lid 3 is fitted to both ends of the mold 2, but the lid 3 may be fitted only to one end of the mold 2. Further, the driving device 4 may be able to contact and separate from the fixed driven device 9, or both the driving device 4 and the driven device 9 may be slidable in the horizontal and horizontal directions. In addition, a power transmission member such as a plurality of gears or an endless drive belt can be used to transmit power from the motor 5 of the drive device 4 to the drive shaft 6. Furthermore, the driving roller 7 and the driven roller 11 can be brought into contact with the outer peripheral surface of the mold 2, or the driving roller 7 and the driven roller 11 can be formed in a long cylindrical shape.
[0020]
【Example】
Hereinafter, examples, comparative examples, evaluations, and mounting tests of the seamless belt molding apparatus according to the present invention will be sequentially described.
Example First, polyamideimide was dissolved in NMP, carbon was blended, and this was used as a material solution. After adjusting the material solution, the driving device 4 of the embodiment is driven to rotate the mold (inner diameter 200 mm, outer diameter 220 mm, length 400 mm) 2 at a speed of 1,000 rpm. 215 g of the material solution was injected into the injection port of the lid (inner diameter 170 mm, outer diameter 220 mm) 3, and the material solution was uniformly applied and leveled on the inner peripheral surface of the mold 2. Then, the temperature of the material solution was increased to 80 ° C. with a hot air blower to promote the reduction of the viscosity of the material solution and the evaporation of the organic solvent, and this state was maintained for 30 minutes to centrifugally mold the seamless belt 1.
[0021]
After the seamless belt 1 was centrifugally molded, the mold 2 was stopped and the mold 2 was set in an oven at 180 ° C. and taken out after 45 minutes. Then, the mold 2 taken out is left to cool at room temperature, and the seamless belt 1 is removed from the mold 2, and then the seamless belt 1 is cut to a length of 260 mm for intermediate transfer with a thickness of 100 μm. A seamless belt 1 was obtained.
[0022]
The drive device 4 is used in place of the driven device 9 of the comparative example embodiment, and the conventional double-sided drive is used, and a method and device substantially the same as those of the example is used to obtain a seamless belt 1 for intermediate transfer having a thickness of 100 μm. It was.
[0023]
When the thickness of the peripheral wall of the seamless belt 1 obtained in the evaluation examples was measured, it was possible to suppress variations within 4 μm (± 2 μm). On the other hand, when the thickness of the peripheral wall of the seamless belt 1 obtained in the comparative example was measured, a variation of 8 μm (± 4 μm) was confirmed.
The seamless belt 1 obtained in the implementation test example and the seamless belt 1 obtained in the comparative example were each set in a color copier and tested 100 × 3 times. The seamless belt 1 of the example was used. In that case, there was no sheet with color misregistration of 0.03 mm or more. On the other hand, when the seamless belt 1 of the comparative example was used, 147 sheets were color-shifted by 0.03 mm or more.
[0024]
【The invention's effect】
As described above, according to the present invention, the mold is rotated only by the plurality of driving rollers and the driven roller is caused to follow the rotation of the mold, so that a difference in speed occurs between the plurality of driving rollers and the driven roller. There is nothing to do. Therefore, there is an effect that it is possible to suppress or prevent chattering when the mold rotates, and to effectively suppress variation in thickness accuracy of a cylindrical molded product such as a seamless belt. Moreover, since the matte black applied to the outer peripheral surface of the mold efficiently absorbs heat from the surroundings, the efficiency of the molding operation can be improved. Moreover, since the hardness of the elastic elastomer which coat | covers a roller is the range of 30 to 90 degreeH, it can prevent that a compression set characteristic deteriorates or a compression load becomes high too much. In addition, since the drive device and its power transmission member can be reduced as compared with the conventional device, simplification of the configuration, easy control, and the like can be expected. Furthermore, since the driven roller slides toward and away from the drive roller, it is possible to facilitate maintenance of the mold and replacement, and to easily deal with molds of different specifications.
[Brief description of the drawings]
FIG. 1 is a front explanatory view showing an embodiment of a seamless belt molding apparatus and a seamless belt manufacturing method using the same according to the present invention.
FIG. 2 is an explanatory side view showing an embodiment of a seamless belt molding apparatus and a seamless belt manufacturing method using the same according to the present invention.
FIG. 3 is a front explanatory view showing another embodiment of a seamless belt molding apparatus and a seamless belt manufacturing method using the same according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Seamless belt 2 Mold 3 Lid 4 Drive device 5 Motor 6 Drive shaft 7 Drive roller 8 Elastic elastomer 9 Drive device 10 Drive shaft 11 Drive roller 12 Elastic elastomer

Claims (2)

A seamless belt molding device that injects liquid material into a rotating cylindrical, horizontally long mold, uniformly leveles the liquid material on the inner peripheral surface, and heats the rotating mold from the periphery to centrifugally mold the seamless belt. Because
A pair of lids that are detachably fitted to both ends of the mold, a plurality of driving rollers that contact and support one lower side of the outer peripheral surface of each lid, and the other lower side of the outer peripheral surface of each lid A plurality of driven rollers that support and rotate as the mold rotates,
Applying matte black on the outer peripheral surface of the mold, the center of each lid as an inlet for liquid material,
A plurality of driven rollers can be slid horizontally and horizontally with respect to a plurality of driving rollers, and the outer peripheral surfaces of the plurality of driving rollers and the driven rollers are made of a heat-resistant elastic elastomer having a hardness of 30 ° to 90 ° H. A seamless belt molding apparatus characterized in that each is coated . A seamless belt manufacturing method using the seamless belt molding apparatus according to claim 1 to manufacture a seamless belt.

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