JPH10236672A - Core for rubber roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow omitting the rubber material fitting operation, lessen the thickness of a rubber material, decrease the temperature dependency, and stabilize a nipping width. SOLUTION: A hole 6 to admit insertion of a shaft 5 is provided at the axis of a column 4, and it is arranged so that a rubber material 3 can be secured to the peripheral surface 7 of the column 4, and a plurality of grooves 8 are provided at the column periphery 7 stretching approx. in the axial direction. Because the rubber material 3 attached to the column periphery 7 will never move owing to the grooves 8, the polishing operation can be performed easily and the thickness be lessened as thin as possible, and as a whole the temperature dependency due to the rubber material 3, and it is possible to stabilize a nipping width.

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 core of a paper feed roller or the like. More specifically, the present invention does not require a rubber material to be fitted, and reduces the rubber thickness. The present invention relates to a rubber roller core that can be made thinner to improve paper feeding accuracy.

[0002]

2. Description of the Related Art A conventional rubber roller core a is shown in FIGS.
As shown in the figure, a hole c for inserting the shaft into the cylinder b is provided in the shaft core, and the rubber material d can be fixed to the outer peripheral surface of the cylinder b. That is, the core a for the rubber roller is
A groove e is provided on the outer peripheral surface of the rubber roller d, and a rubber material d is fitted into the groove e to form a rubber roller f. The rubber roller f has a shaft (not shown) fixed to the hole c, and a rotation force from a driving unit is transmitted to the shaft so that the rubber roller f rotates, thereby exhibiting a function as a paper feed roller or the like. .

[0003]

However, since the rubber roller f fits the rubber material d into the groove e on the outer peripheral surface of the cylinder b, the rubber material d needs to be fitted into the groove e. Requires a portion buried in the groove e and a portion coming out of the groove e, and the rubber thickness as a whole is inevitably thick. As a result, the rubber roller f
Has a high temperature dependency.

[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.

Accordingly, an object of the present invention is to provide a rubber roller core which can eliminate the need for a rubber material fitting operation, reduce the thickness of the rubber material, reduce the temperature dependency, and stabilize the nip width. It is in.

[0006]

Means for Solving the Problems The present invention has been proposed to achieve the above object, and has the following structure. That is, according to the present invention, in a rubber roller core in which a hole through which a shaft is inserted into a cylinder is provided in a shaft core and a rubber material can be fixed to an outer peripheral surface of the cylinder, a plurality of concave stripes are substantially formed on the outer peripheral surface of the cylinder. A rubber roller core provided in the axial direction is provided.

Further, according to the present invention, there is provided the above-mentioned rubber roller core, wherein the concave streak is provided with a cutout in a range of an angle of 5 to 150 degrees from the center of the circular hole.

[0008]

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 II-II of FIG. In the figure, a rubber roller 1 has a rubber material 3 fixed to a rubber roller core 2. The rubber roller core 2 has a hole 6 through which the shaft 5 is inserted into the cylinder 4, and the rubber material 3 can be fixed to the outer peripheral surface 7 of the cylinder 4. 8 is provided in the axial direction.

The rubber roller core 2 is shown in FIGS.
As shown in FIG. 1, a hole 6 is formed in the axis of the cylinder 4 to form a cylindrical portion 10, and a thin portion 11 extends from the axial center portion 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 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
As described above, a plurality of concave stripes 8 are provided in the outer peripheral surface 7 in the axial direction. As shown in FIG. 4, the plurality of concave streaks 8 have circular holes 13 formed in the outer periphery of the annular portion 12 at constant intervals in the axial direction over the entire circumference. As shown in FIG. The notch 14 is provided within an angle range of α to β = 5 to 150 degrees.
The number of the concave stripes 8 is usually 5 or more, and when it is less than 6, the occurrence of the flow mark after molding tends to increase. The shape of the concave stripe 8 may be not only a perfect circle like the circular hole 13 but also an ellipse or an ellipse.

When the rubber material 3 is fixed to the rubber roller core 2, the rubber material 3 enters each of the concave streaks 8 in a state of being in close contact therewith. 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 this embodiment, the outer diameter is 15 mm, the thickness of the rubber material 3 is 1.0 mm, and the hardness is Hs (JI
SA) 50 ° EPDM (ethylene-propylene rubber) is used. The thickness of the rubber material 3 is 0.5 m
m, which can be reduced to one-eighth the thickness of the conventional example of 4 mm, and the finished outer diameter of the rubber roller 1 is temperature-dependent due to the rubber material 3. Of course, there is an advantage that the outer diameter dimension itself can be reduced.

Therefore, according to the present invention, since the rubber material fixed to the outer peripheral surface of the cylinder does not move due to the plurality of recesses in the axial direction, it can be easily polished or the like and can be made as thin as possible. As a whole, the temperature dependency of the rubber material is reduced, and the nip width can be stabilized. In addition, as defined in claim 2, a circular hole is formed in the entire peripheral edge of the cylinder in the axial direction, and the circular hole is formed in 5 to 15 holes.
By forming a ridge by notching within the range of an angle of 0 degrees, the rubber material fixed to the outer peripheral surface of the cylinder does not move due to the ridge of the above shape, and is processed by polishing or the like. This also has the effect of making it easier.

Hereinafter, a method for manufacturing the rubber roller 1 will be described. A rubber roller core 2 having a plurality of concave stripes 8 shown in FIGS. 4 and 5 is molded, and a rubber material 3 is integrated with the rubber roller core 2 by injection molding. That is, the rubber roller core 2 is set in the mold. Next, the rubber material 3 in the heat-melted state is mainly contained in the plurality of concave stripes 8.
Is injected. As a result, the EPDM in the heated and fluidized state is solidified in the plurality of recesses 8 and the outer periphery of the annular portion 12, that is, the outer peripheral surface 7 of the cylinder 4, and the surface of the EPDM is polished to manufacture the rubber roller 1.

The above injection molding is performed by
The test was performed under the conditions of a cylinder temperature of 170 ° C., a mold temperature of 170 ° C., and a curing time of 5 minutes. Therefore, the rubber material 3 can be fixed to the rubber roller core 2 without using an adhesive, so that the fitting operation is eliminated, and the rubber material 3 has a plurality of concave stripes 8.
It is possible to obtain the rubber roller 1 having a high-precision outer diameter without moving when polishing the surface and polishing the surface.

In the above-described embodiment, a description has been given of an embodiment in which the concave streak 8 is formed by making the notch 14 into the circular hole 13 within a range of an angle of 5 to 150 degrees. However, the present invention is not limited thereto. However, the shape of the concave stripe 8 may be any shape as long as the rubber material 3 does not move in the thrust and circumferential direction or drop off when the rubber material 3 is fixed to the rubber roller core 2. Holes, zigzag grooves and the like may be used. The number of the circular holes 13 is 24. In this case, the rubber material 3 has a hardness of about 90 ° according to JISA.
When the number of the circular holes 13 is about 8, JISA50 °
It is preferable to use one having a degree of hardness. That is, when the number of the circular holes 13 is small, a material having a low hardness and high fluidity may be used, and when the number of the holes 13 is large, a material having a high hardness and low fluidity may be used.

The material of the rubber material 3 is not limited to the above, but includes styrene / butadiene rubber, butadiene / acrylonitrile rubber, natural rubber, chlorosulfonated polyethylene, silicone rubber, fluorine rubber, chloroprene rubber, urethane Rubber, polynorbornene, thermoplastic elastomer and the like can be used.

[0017]

Next, as an example, a change in the outer diameter dimension due to a temperature difference between the rubber roller 1 and the conventional rubber roller in the above configuration is measured.

<Embodiment 1> A rubber roller 1 is shown in FIGS. 1 and 2. The material of the rubber roller core 2 is 66 nylon resin, and the material of the rubber material 3 is JIS A hardness 50 °.
EPDM, whose outer diameter is 20 ° C.
5 mm, 0 ° C, 10 ° C, 20 ° C, 30 ° C, 40 ° C,
The outer diameter is measured at 50 ° C.

Comparative Example 1 A rubber roller is shown in FIGS. 7 and 8, and other conditions and a measuring method are the same as those in Example 1. FIG. 6 shows the result. According to FIG. 6, the change in the outer diameter of the rubber roller is 0.001 m in the first embodiment.
m / ° C., and 0.004 mm / ° C. in Comparative Example 1, giving a four-fold difference.

Although the embodiment of the present invention has been described above, the present invention is not limited to this embodiment without departing from the gist of the present invention.

[0021]

As described in detail above, according to the present invention,
The rubber material fixed to the outer peripheral surface of the cylinder does not move or fall off due to the plurality of axially extending ridges, so it can be thinned as much as possible by polishing etc., and the temperature dependency due to the rubber material is reduced as a whole I do. Therefore, according to the rubber roller core, the outer diameter of the rubber roller is less changed by temperature and the nip width is stable, so that the paper can be fed stably and reliably even when used as a paper feed roller or the like. Also,
According to the invention of claim 2, since a circular hole is formed in the entire peripheral edge of the cylinder in the axial direction, and the circular hole is formed with a notch within an angle of 5 to 150 degrees, a concave streak is formed. The rubber material fixed to the outer peripheral surface of the cylinder does not move due to the above-described concave streak, and has an effect that the processing is facilitated.

[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 the line II-II of FIG.

FIG. 3 is a cross-sectional view illustrating a concave streak.

FIG. 4 is a side view of a rubber roller core showing an embodiment of the present invention.

FIG. 5 is a sectional view taken along line VV in FIG. 4;

FIG. 6 is a characteristic diagram showing a temperature change of an outer diameter dimension of a rubber roller.

FIG. 7 is a perspective view showing a conventional example.

FIG. 8 is a sectional view showing a conventional example.

DESCRIPTION OF SYMBOLS 1, f rubber roller 2, a rubber roller core 3, d rubber material 4, b cylinder 5 shaft 6, c hole 7 outer peripheral surface 8 concave streak 10 cylindrical part 11 thin part 12 annular part 13 circular hole 14 Notch e groove

Claims (2)

[Claims] 1. A rubber roller core, wherein a hole through which a shaft is inserted into a cylinder is provided in a shaft core, and a rubber material can be fixed to an outer peripheral surface of the cylinder. A core for a rubber roller, wherein the core is provided. 2. The rubber roller core according to claim 1, wherein the recess has a cutout in the circular hole within a range of 5 to 150 degrees from the center thereof.