JP2003292188A - Paper feeding conveying roller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeding conveying roller having high durability while lowering its hardness, capable of stably keeping its coefficient of friction without being affected by paper powder, having high abrasion resistance, and free from noise. <P>SOLUTION: This paper feeding conveying roller used in feeding or conveying sheets has a layer 12 formed on a core metal 11 and composed of a low-foamed elastic body of foaming magnification of 1.05-1.5 times. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding / conveying roll used for various sheet feeding / conveying rolls of various office automation equipment such as copiers, facsimiles and various printers.

[0002]

2. Description of the Related Art Conventionally, rolls for feeding and carrying various OA equipment are required to have a great carrying force and excellent wear resistance. For this reason, EPDM has been conventionally used.
A material having excellent mechanical strength and a high friction coefficient such as (ethylene / propylene / diene rubber) or chlorinated polyethylene rubber, silicone rubber or polyurethane rubber is used as a material for the roll.

Such a paper feeding / conveying roll has a problem that the rate of change in the friction coefficient is large due to the influence of paper dust or the like due to long-term use and the durability is poor, and the friction with the paper or the like at the time of paper feeding. There is a problem in that a so-called squeal phenomenon occurs due to the vibration caused by.

[0004]

Therefore, it has been proposed to prevent squeal by adding a plasticizer or the like to reduce the hardness. However, in such a method of reducing the hardness, compression is performed. Permanent strain decreases, paper feeding capacity decreases,
Also, there arises a problem that wear resistance is lowered and durability is lowered.

On the other hand, it is possible to use a foamed elastic body to reduce the hardness, but there is a problem in terms of durability.

In view of this, in Japanese Patent Laid-Open No. 2001-341862, there are two layers, an inner layer of a foamed elastic body and an outer layer of a non-foamed elastic body.
A paper feed roll formed of a layered structure has been proposed. Since this paper feed roll has a foamed elastic body in the inner layer, it has a lower hardness as a whole than the single-layer structure of a non-foamed elastic body and can secure a large nip amount to obtain stable paper feeding performance and to be durable. Abrasive performance depends on the layer of non-foamed elastomer.

However, this two-layer roll has a problem of higher cost than a single layer. Further, since the surface is a non-foamed elastic body, there remains a problem that the friction coefficient is apt to decrease with time due to the influence of paper powder as described above.

In view of such circumstances, the present invention has a low hardness and an excellent durability, can maintain a stable friction coefficient without being affected by paper dust, and has high wear resistance and An object of the present invention is to provide a paper feed / conveyance roll that does not generate squeal.

[0009]

As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that a roll for feeding and feeding a foamed elastic body having a foaming ratio in a specific range is a non-foamed elastic body. The present invention has been completed by obtaining new knowledge that higher wear resistance can be obtained than that of the sheet feeding / conveying roll.

The first aspect of the present invention is a paper feed / conveyance roll used for feeding or conveying paper sheets,
A sheet feeding / conveying roll comprising a core metal and a layer made of a low-foaming elastic body having a foaming ratio of 1.05 to 1.5.

A second aspect of the present invention is the sheet feeding / conveying roll according to the first aspect, wherein the low expansion elastic body has a foaming ratio of 1.1 to 1.2 times.

According to a third aspect of the present invention, in the first or second aspect, a thin rubber-like elastic layer is provided between the core metal and the layer made of the low foam elastic body. It is located on the paper feed roll.

Here, the low-foaming elastic body of the paper feeding / conveying roll of the present invention can be manufactured from a conventionally selected material selected from various foamed rubbers and foamed thermoplastic elastomers. Specifically, EPDM, NBR, SBR, N
Rubber materials such as R and polyurethane rubber, and thermoplastic elastomer materials such as polyethylene-based or polystyrene-based elastomers can be used.

The expansion ratio of the low expansion elastic body is 1.05 to 1.
It is preferably 5 times, more preferably 1.1 to
It is 1.2 times. The expansion ratio can be adjusted by applying the amount of the foaming agent and applying pressure during foaming.

As described above, when the sheet feeding / conveying roll is formed of the layer made of the low foaming elastic body and the expansion ratio is in the range of 1.05 to 1.5 times as described above, the abrasion resistance is high, Further, such a paper feeding / conveying roll has improved wear resistance as compared with the paper feeding / conveying roll formed of a single layer of a non-foamed elastic body.

The low-foam elastic material may be open-cell or closed-cell.

Further, since the rubber roll of the present invention has a low rubber hardness of 10 ° to 40 ° according to JIS A, a large amount of deformation (nip amount) under a constant pressure load is applied to feed the roll. While maintaining the transport characteristics, it is possible to obtain high vibration absorption performance without lowering durability.
Squeaking can be effectively prevented. Further, since it is a foam, it has a large surface roughness, and a nip amount can be secured even if the base rubber material has a high hardness, which makes it possible to maintain the predetermined paper feed and transport characteristics, and to prevent paper dust and the like adhering to the surface. By entering into the concave portion of the foam, it is possible to suppress the reduction of the friction coefficient due to the paper powder, which has been a problem in the past.

The paper feeding / conveying roll of the present invention can also be used for feeding and conveying paper such as recycled paper containing aluminum oxide, calcium carbonate, titanium oxide, and silica components.
It is needless to say that the paper feeding / conveying roll of the present invention has the same effect as or better than the conventional roll even when paper sheets other than recycled paper are used.

In the paper feed / conveyance roll of the present invention, the layer made of the low-foam elastic material described above may be directly provided on the core metal, but the layer made of the low-foam elastic material and the metal core may be provided. A thin rubber elastic layer may be provided on the cored bar to prevent the slip.

The paper feeding / conveying roll of the present invention can be manufactured by providing a low foaming elastic body on a cored bar or on a thin rubber elastic layer provided on the cored bar.

As for the material of each layer, it is preferable to select a material that allows each layer to be easily joined, and it is preferable to select a material of the same type or a material that is easily compatible with each other. When the thin rubber-like elastic layer is provided on the core metal, it is preferably formed by applying a solution in which a rubber material is dissolved in a solvent.

It should be noted that each layer may be provided with conductivity, and by doing so, it is possible to prevent the generation of static electricity during sheet feeding and conveyance.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to Examples, but these Examples do not limit the scope of the present invention in any way.

FIG. 1 shows a cross section of a sheet feeding / conveying roll according to one embodiment. As shown in FIG. 1A, the sheet feeding / conveying roll 10 includes a cored bar 11 and a low foam elastic body layer 12.

The low expansion elastic layer 12 has an expansion ratio of 1.0.
It is made of a foam having a thickness of 5 to 1.5 times and a thickness of 1 mm or more.

As shown in FIG. 1B, the core metal 11
And the low-foam elastic layer 12 between the thin rubber-like elastic layer 1
The sheet feeding / conveying roll 10 </ b> A having the number 3 may be used.

An example of manufacturing such a sheet feeding / conveying roll 10 will be described with reference to FIG.

As shown in FIG. 2, a cylindrical first mold 2 is provided.
The second mold 22 for closing the bottom surface is set at 1, and the upper end is closed by the third mold 23 with the core metal 11 around which the pre-foaming low foam elastic layer 12a is wound. By performing a heat treatment in this state, the pre-foaming low-foaming elastic body layer 12a is foamed and molded.

After that, the outer peripheral surface was polished to adjust the outer diameter and the center deviation, and the roll 10 was formed.

(Examples 1 to 3) As shown in Table 1 below,
By varying the foaming ratio of the layer made of the low-foaming elastic body, the paper feeding and conveying rolls of Examples 1 to 3 having a thickness of 6 mm, an outer diameter of 25 mm and a width of 20 mm were manufactured. The rubber hardness and the friction coefficient are also shown in Table 1.

(Comparative Example 1) As shown in Table 1 below, a single layer of highly foamed elastic material, having a thickness of 6 mm, an outer diameter of 25 mm and a width of 20.
mm feed rolls were manufactured. The total rubber hardness and friction coefficient are also shown in Table 1.

(Comparative Example 2) As shown in Table 1 below, a non-foamed elastic single layer having a thickness of 6 mm, an outer diameter of 25 mm, and a width of 20 was used.
mm feed rolls were manufactured. The total rubber hardness and friction coefficient are also shown in Table 1.

(Test Example 1) A paper is fed from the roll paper 20 along the surface of the base 30 by the abrasion tester shown in the schematic view of FIG. The amount of wear when the roll 10 is rotated and fed and fed is
The paper feeding / conveying rolls of Examples 1 to 3 and Comparative Examples 1 and 2 were examined. The roll paper 20 is fed at a feed speed of 1 mm / sec, and the paper feed roll 1
The number of revolutions of 0 was set to 250 rpm, and the amount of wear after 30,000 revolutions was examined. The results are shown in Table 1.

From the results shown in Table 1, it was found that the wear amount in Examples 1 to 3 was smaller than that in the Comparative Example, and the paper feeding and conveying roll of the present invention had high wear resistance.

(Test Example 2) Examples 1 to 3 and Comparative Example 1,
150,000 sheets (150K) using 2 paper feed rolls
Was continuously fed and the change in friction coefficient was investigated.

As shown in Table 1, the rolls of Examples 1 to 3 showed less decrease in friction coefficient than the rolls of Comparative Example.

[0037]

[Table 1]

[0038]

As described above, according to the present invention,
(EN) It is possible to provide a paper feeding / conveying roll that has low hardness and excellent durability, can maintain a stable friction coefficient without being affected by paper powder, has high abrasion resistance, and does not cause squeaking. it can.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a sheet feeding / conveying roll according to an embodiment of the present invention.

FIG. 2 is a schematic view showing an example of a manufacturing process of a sheet feeding / conveying roll of the present invention.

FIG. 3 is a schematic view showing an abrasion tester of Test Example 1.

[Explanation of symbols]

10 Paper feed roll 11 core 12 Low foam elastic layer 13 Rubber-like elastic layer 20 roll paper 30 units

Continued front page    F term (reference) 3F049 AA03 CA12 CA15 CA16 LA02                       LA05 LA07 LB03                 3F343 FA02 FA03 FB02 FB03 FC22                       FC23 FC28 JA11 KB16

Claims (3)

[Claims] 1. A paper feeding / conveying roll used for feeding or conveying paper sheets, wherein the expansion ratio is 1.05 on a core metal.
A roll for feeding and feeding a sheet, characterized by comprising a layer made of a low foaming elastic body having a ratio of up to 1.5 times. 2. The sheet feeding / conveying roll according to claim 1, wherein the low expansion elastic body has a foaming ratio of 1.1 to 1.2 times. 3. The sheet feeding / rolling roll according to claim 1, further comprising a thin rubber elastic layer between the core metal and the layer made of the low foam elastic body.