JPH11246061A - Core for rubber roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hold stable paper feeding accuracy over a long period of time while dispensing with rubber material fit-in work and preventing air from being sealed at the time of securing the rubber material. SOLUTION: This core 2 for a rubber roller is provided with a hole at its axis center so as to insert a shaft through, and rubber material is integrally secured to the outer peripheral surface of a cylinder 4 through a protruded outer peripheral member 6 concentric with the cylinder 4. The outer peripheral member 6 is an aggregate of T-shaped members erectly provided at nearly equal spaces on the outer peripheral surface of the cylinder 4. It is desirable that the width of each slit 9 formed between the T-shaped outer peripheral members 6 is 1 mm to 5 mm, and it is further desirable that semicircular or elliptic through-space larger than the slit width is formed below the slit 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber roller core mounted on a shaft portion of a paper feed roller or the like. More specifically, the present invention does not require a rubber material fitting operation and fixes a rubber material. The present invention relates to a core for a rubber roller capable of preventing air from being enclosed at the time of cleaning and maintaining stable feeding accuracy for a long period of time.

[0002]

2. Description of the Related Art A conventional rubber roller core has a core 52 inside a rubber roller 50 as shown in an exploded perspective view of FIG.
Is fitted. As shown in FIG. 6, a groove 51 is formed in the outer periphery of the core 52 over the entire circumferential direction.
0 is attached. The rubber roller has a shaft (not shown) fixed to the hole, and a rotational force from a driving means is transmitted to the shaft to rotate, so that a function as a paper feed roller or the like is exhibited.

[0003]

However, since the rubber roller fits the rubber material into the groove on the outer peripheral surface of the cylinder, the rubber material needs to be fitted with the rubber material. And a portion coming out of the groove are required, and the rubber thickness as a whole is formed to be thick. As a result, the temperature dependency of the rubber roller f increases.

[0004] The temperature dependence is such that the rubber shrinkage varies depending on the temperature. Normally, the rubber expands when the temperature increases, and the rubber contracts when the temperature decreases. Therefore, when the temperature is high, the outer diameter of the rubber roller f is reduced. When the temperature is low, the outer diameter of the rubber roller f decreases, and when the temperature is low, the pressure contact force with the paper is small. Indicates that the nip width is too small to feed the paper.

In order to solve the above-mentioned drawbacks of the prior art, the present inventors have made it unnecessary to insert a rubber material, to reduce the thickness of the rubber of the rubber roller, and to process the external dimensions with high precision. For the purpose of providing a possible rubber roller core, a rubber roller core having a through hole that penetrates both ends in the axial direction in a state where the rubber roller is fixed without being opened to the outer periphery has been developed and patent application has been made. (Japanese Unexamined Patent Publication No. Hei 8-208089).

[0006] The present inventors have tried the above invention, and in the course of further research, in the process of firmly integrating the cylinder made of resin and the rubber roller, a slight air intervention between the cylinder and the rubber member. It has been found that the presence of this air causes the outer diameter of the rubber roller to gradually deviate over time, and the paper feeding mechanism using the rubber roller gradually becomes less stable.

It is an object of the present invention to provide a rubber roller core which can prevent even a small amount of air from being interposed between a cylindrical member made of resin and a rubber member formed on the outer periphery thereof. . Another object of the present invention is to provide a rubber roller for paper feeding that can maintain a stable paper feeding function for a long period of time.

[0008]

DISCLOSURE OF THE INVENTION The present invention has been proposed to achieve the above object, and is intended for injection molding rubber around the outer periphery of a columnar member made of resin and fixing and integrating the same. The air interposed between the two is absorbed into a slit-shaped space formed in the outer peripheral member protruding from the outer periphery of the cylindrical member, and the outer diameter of the rubber roller formed on the outer periphery is integrated with high precision. There is an important feature in this point.

That is, according to the present invention, there is provided a rubber roller for providing a hole through which a shaft is inserted in a shaft core, and for fixing and integrating a rubber material on an outer peripheral surface of a cylinder via a projecting outer peripheral member concentric with the cylinder. In the core, the outer peripheral member is an aggregate of T-shaped members erected on the outer peripheral surface of the cylinder at substantially equal intervals, and a core for a rubber roller is provided. Further, according to the present invention, there is provided the rubber roller core, wherein a slit width formed between the T-shaped outer peripheral members is 1 to 3 mm.

Further, according to the present invention, there is provided the rubber roller core, wherein the lower part of the slit is formed in a through space larger than the slit width.

Further, according to the present invention, there is provided the rubber roller core, wherein the through space is formed in a semicircular or elliptical shape.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of a rubber roller according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line XX of FIG. In the figure, a rubber roller 1 has a rubber material 3 fixedly integrated with a rubber roller core 2 by injection molding. The rubber roller core 2 is provided with a hole 5 through which a shaft is inserted into the cylinder 4 at the axis thereof and an outer peripheral surface 7 of the cylinder 4.
Then, an outer peripheral member 6 concentric with the cylinder is protruded, and through this, the cylinder made of resin and the rubber roller are firmly integrated.

The rubber roller core 2 is shown in FIGS.
As shown in FIG. 2, a hole 5 is formed in the axis of the cylinder 4 to form a cylindrical portion 10, and a thin portion 11 extends from the central portion in the axial direction on the outer peripheral surface of the cylindrical portion 10. Further, an annular portion 12 is provided concentrically with the cylindrical portion 10 on the outer peripheral portion 7 of the thin portion 11. The column 4 is made of 66 nylon resin, polybutylene terephthalate, polyacetal resin, polycarbonate resin or the like.

The outer periphery of the annular portion 12, that is, the column 4
The outer peripheral member 6 is provided around the outer peripheral surface 7 concentrically with the cylinder. As shown in FIG. 3, the outer peripheral member 6 is formed as an aggregate of T-shaped members that stand on the outer peripheral surface of the column at substantially equal intervals. The slit 9 formed between the T-shaped outer peripheral members absorbs air interposed between the cylinder and the rubber member,
Prevents air from being trapped in the rubber roller.

Of course, the outer diameter of the rubber roller must not cause a dimensional error due to the presence of the slits 9, so that air absorption is preferably performed and a dimensional error is not caused in the outer diameter of the rubber roller. The width of the slit is slightly different depending on the size of the rubber roller,
It was confirmed that the range was 1 to 5 mm. The width of the outer peripheral member 6 is not particularly limited as long as it is smaller than the width of the column.
It is preferably as narrow as about 1.2 mm. Further, in order to properly absorb air, it is important that a through space 8 larger than the slit width is formed below the slit, and the cross sectional shape of the through space 8 is circular. Is particularly preferable, and it is particularly preferable that the shape is formed in a semicircular or elliptical shape.

It is necessary that the volume of the through space 8 is larger than the volume of the rubber member injection-molded outside the outer peripheral member, so that even if a large amount of air is mixed in the rubber member, All of the air can be absorbed in the through space, and no air remains between the cylinder and the rubber.

When the rubber material 3 is fixed to the rubber roller core 2, the rubber material 3 enters the slit 61 and the through space 62 of the outer peripheral member 6 in close contact. Therefore, the rubber material 3 does not move in the axial direction and the circumferential direction of the rubber roller core 2, and high-precision polishing can be performed. In the rubber roller 1 of the present embodiment, the outer diameter is 15 mm, the thickness of the rubber material 3 is 1.0 mm, and EPDM (ethylene-propylene rubber) having a hardness of 50 degrees Hs (JISA) is used as the material. I have. In addition, the rubber material 3
The thickness of the core is 0.5 by applying an adhesive to the outer diameter of the core.
Since it can be manufactured up to about mm, there is an advantage that the finished outer diameter of the rubber roller 1 can be less dependent on temperature due to the rubber material 3 and the outer diameter can be reduced accordingly.

Therefore, according to the present invention, air does not intervene between the cylinder and the rubber member, so that air is not sealed in the rubber in the molten state and air remains in the rubber roller. In addition, the rubber material fixed to the outer peripheral surface of the cylinder does not move because of the interposition of the outer peripheral member, so that highly accurate polishing can be performed.

In order to manufacture the rubber roller 1 using the core of the present invention, a rubber material such as EPDM may be injection-molded in a state where the core previously formed of resin is set in an injection molding die. . The rubber material is solidified and integrated on the outer peripheral surface 7 of the cylinder 4 to form a rubber roller as a whole, and the surface thereof is polished to manufacture the rubber roller 1.

In the present embodiment, the cylinder temperature is 170 ° C., the mold temperature is 170 ° C., and the curing time is 5 minutes.
Minutes. The number of the T-shaped outer peripheral members 6 is not particularly limited, and although it depends on the size of the rubber roller, usually, about 8 to 16 can achieve the purpose. In the illustrated example, eight examples are shown.

As the rubber material 3, EPDM, styrene
Butadiene rubber, butadiene / acrylonitrile rubber,
Natural rubber, chlorosulfonated polyethylene, silicone rubber, fluorine rubber, chloroprene rubber, polyurethane rubber, polynorbornene, thermoplastic elastomer, and the like can be used, and EPDM is particularly preferably used. The hardness of the rubber material is preferably about 30 to 70 ° according to JISA.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments without departing from the gist of the present invention.

[0023]

As described in detail above, according to the present invention,
Even when air is present in the system during molding, especially when injecting the rubber member, this air is not encapsulated in the molten rubber, and air remains in the rubber roller as the final product. In addition to not impairing the accuracy of the outer diameter of the rubber roller, the rubber material fixed to the outer peripheral surface of the cylinder is integrated with the outer peripheral member in the axial direction and the through space thereof in a tightly entangled state, so that polishing is performed. A rubber roller having high dimensional accuracy can be easily obtained with ease of operation.

[Brief description of the drawings]

FIG. 1 is a side view of a rubber roller according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line XX of FIG.

FIG. 3 is a side view showing the shape of the rubber roller core of the present invention.

FIG. 4 is a sectional view taken along line YY of FIG. 4;

FIG. 5 is an exploded perspective view of a rubber roller using a conventional rubber roller core.

FIG. 6 is a cross-sectional view of a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 rubber roller 2 core for rubber roller 3 rubber material 4 cylinder 5 shaft insertion hole 6 outer peripheral member 7 outer peripheral surface 8 penetration space 9 slit 10 tubular portion 11 thin portion 12 annular portion 50 rubber roller (conventional example) 51 groove portion (conventional example) 52 rubber roller Core (conventional example)

Claims (4)

[Claims] 1. A rubber roller core, wherein a hole through which a shaft is inserted is provided in a shaft core, and a rubber material is fixedly integrated with an outer peripheral surface of a cylinder via a projecting outer peripheral member concentric with the cylinder. Is a set of T-shaped members erected at substantially equal intervals on the outer peripheral surface of a cylinder, and is a core for a rubber roller. 2. The rubber roller core according to claim 1, wherein a slit width formed between the T-shaped outer peripheral members is 1 to 5 mm. 3. The rubber roller core according to claim 1, wherein a lower portion of the slit is formed in a through space larger than a slit width. 4. The rubber roller core according to claim 3, wherein the through space is formed in a semicircular or elliptical shape.