JPH10196738A - V-ribbed belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the wear of rubber so as to prevent the generation of abnormal sound by composing an outer cover canvas rubber complex of outer cover canvas impregnated or coated with particular rubber and an adhesive rubber layer in a V-ribbed belt where a core body is provided between upper rubber and lower rubber and the upper rubber is covered with the outer cover canvas rubber complex. SOLUTION: A v-ribbed belt is constructed in such a manner that a core body 4 is arranged between upper rubber 1 and bottom rubber 2 so as to be extended in a belt longitudinal direction and fixed by adhesive rubber 3, a plurality of grooves 5 V-shaped in section are continuously formed in the bottom rubber 2 and the upper rubber 1 is covered with an outer cover canvas rubber complex 6. In this case, the outer cover canvas rubber complex 6 is composed of outer cover canvas 7 impregnated with rubber, a backside rubber layer 8 coated on the surface of the outer cover canvas 7, a backside rubber layer 9 coated on the surface of the outer cover canvas 7 and an adhesive rubber layer 10 coated on the backside rubber layer 9. The rubber of the backside rubber layer 8 is one where carbon of 40 to 80wt.% is mixed for CR polymer 100wt. part and hardness prescribed by JIS-A standard is 77 to 90 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a V-type belt used as an accessory driving belt for driving an engine accessory such as a generator or a cooling fan of an automobile or an oil pump.
It relates to a ribbed belt.

[0002]

2. Description of the Related Art V-ribbed belts are widely used as accessory driving belts because they have both the flexibility of flat belts and the high power transmission of V-shaped belts. This V
The original use of the ribbed belt was to use the front side of the belt where the ribs were formed around the crank pulley and the auxiliary pulley, but a flat pulley was used as an idler on the back of the belt. As a result, a sufficient driving force has been applied to the auxiliary pulley, or an idler has been applied to the back surface of the belt to change the running direction of the belt so that the belt does not interfere with the engine parts. In recent years, the drive load of alternators and air conditioner pumps has increased due to the luxury orientation of passenger cars.Also, it is called a serpentine drive for the purpose of reducing the number of accessory drive belts and reducing the space for accessories. Multi-axis hanging has been adopted.

In this serpentine drive, all the pulleys connected to each of a large number of auxiliary machines are arranged on the same plane, and one pulley is hung on those pulleys to drive a part of the pulleys rearward. In order to secure a winding angle around each pulley, the belt has a layout with many irregularities. Also, by attaching a crown to the pulley on the back of the belt, the running stability of the belt has been improved by utilizing the behavior that the belt is easily flowed to the side with a high tension. Tension is easily applied to the center.

As described above, in the V-ribbed belt, the conditions of use of the back portion thereof have become more severe in recent years, and the load has been increasing. In particular, the load applied to the outer canvas rubber composite of the V-ribbed belt is large, causing a problem of wear.

On the other hand, Japanese Unexamined Patent Publication (Kokai) No. 6-323368 discloses a belt provided by impregnating rubber into an outer canvas provided on the back side of a V-ribbed belt and further applying rubber to the surface of the outer sail. By forming a back rubber layer forming a back surface, the back rubber layer is made of a rubber composition containing CR (chloroprene) polymer, hard carbon and conductive carbon as main components, whereby the resistance of the back rubber layer is improved. It is described that the wear property is improved.

[0006]

However, as described above, V
When the use conditions of the ribbed belt become severe and the load applied to the rear surface increases, it is necessary to further enhance the wear resistance of the rear surface. That is, as shown in FIG. 6, when the rubber on the back surface of the belt is worn, the abrasion powder generates an adhesive material a in the form of an eraser scum, and the adhesive material a causes a step on the back surface of the belt. For this reason, when the adhesive substance a comes into contact with the flat pulley, an abnormal sound (slapping sound) is generated.

Accordingly, the present invention is to prevent the occurrence of the above-mentioned abnormal noise by preventing an eraser-rubber-like sticky substance from being produced on the back surface of the belt due to the wear of the rubber.

[0008]

According to the present invention, a rubber composition comprising a CR polymer and a relatively large amount of carbon is used for the rubber constituting the back surface of the V-ribbed belt and the hardness of the rubber is increased. Thus, the expected effect can be obtained by suppressing the abrasion of the rubber as described above.

That is, the invention of this application is based on
A bottom rubber, a core body provided between the upper rubber and the bottom rubber, extending in the longitudinal direction of the belt, and fixed by an adhesive rubber; a plurality of V-shaped grooves in the bottom rubber in the longitudinal direction of the belt; In a V-ribbed belt in which the upper rubber is covered with an outer canvas rubber composite while being continuously formed, the outer canvas rubber composite is impregnated or coated with rubber and the rubber is provided on the back surface of the V-ribbed belt. (Exposed on the entire back surface of the belt), and an adhesive rubber layer provided on the back side of the outer fabric and adhering the outer rubber composite to the upper rubber. The rubber forming the back surface of the belt contains 40 to 80 parts by weight of carbon with respect to 100 parts by weight of CR polymer, and has a hardness of 77 to 90 ° specified by JIS-A. Ariko The features.

In the present invention, the addition of carbon to the CR polymer increases the elasticity of the rubber on the back surface of the belt and increases its hardness, and a large load is applied to the back surface of the belt by a flat pulley, so that the back rubber is greatly affected. Even when a shearing force is applied, the rubber is less likely to slip or slip, and even if the slip is slightly generated, the rubber is hard to cause rubber abrasion due to its high rubber hardness.

Here, if the rubber hardness is less than 77 °, the above-mentioned effect of preventing slippage or slip cannot be sufficiently obtained, and if the rubber hardness exceeds 90 °, abnormal heat generation easily occurs on the back surface of the belt. This causes premature belt damage. The reason for setting the carbon content to 40 to 80 parts by weight is that if the amount is small, the rubber hardness cannot be increased, while if the amount is excessive, the rubber hardness is 90 °. This is because it is difficult to suppress the temperature to below, and there is a problem that the scorching of the rubber advances and the processing becomes difficult.

[0012] With regard to the outer cover rubber composite, the outer cover is impregnated with rubber; a back rubber layer applied to the outer surface of the outer cover fabric to form the back surface of the V-ribbed belt; A back rubber layer applied to the back of the canvas, and an adhesive rubber layer provided on the back rubber layer and bonding the outer canvas rubber composite to the upper rubber, the rubber of the back rubber layer Can be obtained by mixing 40 to 80 parts by weight of carbon with respect to 100 parts by weight of CR polymer, and having a hardness of 77 to 90 ° specified by JIS-A.

In this case, the back rubber layer formed by coating the outer canvas comes into contact with the flat pulley. This back rubber layer is obtained by blending a relatively large amount of carbon with CR polymer. Since the rubber hardness is high, high wear resistance can be obtained.

[0014] Further, as for the above-mentioned outer canvas rubber composite, the outer canvas is impregnated with rubber, and the outer canvas rubber composite provided on the back side of the outer canvas is attached to the upper rubber. An adhesive rubber layer to be adhered, wherein the rubber impregnated in the outer sail cloth forms the back surface of the V-ribbed belt, and the impregnated rubber of the outer sail cloth is applied to 100 parts by weight of the CR polymer. 40 to 80 parts by weight of carbon may be blended, and the hardness specified by JIS-A may be 77 to 90 °.

In this case, the impregnated rubber of the outer canvas comes into contact with the flat pulley, and the impregnated rubber also has a rubber hardness obtained by blending a relatively large amount of carbon with the CR polymer as described above. Since they are high, they also have high abrasion resistance. Further, since there is no back rubber layer and the outer cloth impregnated with rubber comes into contact with the pulley, the contact surface between the pulley and rubber is reduced, which is advantageous in preventing the rubber from sticking.

In each of the above inventions, it is preferable that a part of the carbon is made of soft carbon.
That is, if the compounding amount of carbon in the rubber is large, the burning becomes difficult and the processing of the rubber becomes difficult, as described above, and the tendency becomes remarkable particularly when the rubber is composed only of hard carbon or conductive carbon. However, soft carbon is advantageous in preventing a decrease in workability.

[0017]

Therefore, according to the invention of this application, the back rubber layer or the impregnated rubber constituting the outer canvas rubber composite of the V-ribbed belt is composed of 40 to 80 parts by weight of carbon per 100 parts by weight of CR polymer. It is blended and JIS
Since the hardness specified by -A is 77 to 90 °, the abrasion resistance of the back surface of the belt is improved, the generation of an eraser-like sticky substance is suppressed, and the generation of abnormal noise can be prevented. .

Further, according to the method in which soft carbon is partially used, the rubber hardness can be increased by increasing the compounding amount of carbon while avoiding a decrease in the processability of the rubber. This is advantageous in obtaining abrasion resistance.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the V-ribbed belt shown in FIG. 1, 1 is an upper rubber, 2 is a bottom rubber, and both rubbers 1, 2
A core body 4 extending in the longitudinal direction of the belt and fixed by an adhesive rubber 3 is provided therebetween. A plurality of V-shaped cross-section grooves 5 are continuously formed in the bottom rubber 2 in the longitudinal direction of the belt, and the upper rubber 1 is covered with an envelope rubber composite 6.

As shown in FIG. 2, the outer cover fabric rubber composite 6 is composed of an outer cover fabric 7 impregnated with rubber, and a back rubber layer 8 applied to the surface side of the outer cover fabric 7 as a seal for the same. And a backside rubber layer 9 applied to the backside of the outer cover fabric 7 as a texture of the same canvas 7 and an adhesive rubber layer 10 applied to the backside rubber layer 9. Here, as the outer covering cloth 7, a strong cloth such as a cotton cloth is used. The impregnated rubber and the back rubber of the outer sail cloth 7 are preferably configured as follows from the viewpoint of preventing abrasion of the back of the belt and generation of abnormal noise when the belt is used.

That is, the rubber impregnation in the outer cloth 7 is performed by immersing the outer cloth in a rubber paste obtained by dissolving the rubber composition in an organic solvent (for example, toluene).
For the back rubber, a rubber paste is similarly prepared and coated on the outer sail cloth 7 impregnated with the rubber. The basis weight of the back rubber layer 8 is set to 16 to 48 g / m ² . The reason for this is that it is very difficult to control the amount of less than 16 g with the coating. The reason for setting the content to 48 g or less is that if the back surface layer has a large amount of rubber, it is rather easy to wear.

<Relationship Between Rubber of Back Rubber Layer and Belt Performance> As shown in Table 1, a vulcanization test was carried out with rubber compositions A to H having different types and amounts of carbon.
The hardness of the obtained rubber was measured. HAF carbon is hard type furnace black, and FEF carbon is soft type furnace black. In addition, V-ribbed belts (shown in FIG. 1) each having a back rubber layer formed from the rubber compositions A to H were prepared, and an adhesion test and a heat resistance running test on the back of the belt were performed.

FIG. 3 shows an embodiment of the adhesion test. That is,
Test belt 1 for driving pulley 11 and driven pulley 12
3 is hung on the back, a weight DW of 120 kgf is given to the driven pulley 12, and the driving pulley 11 is set at 3500 rpm.
To check the presence or absence of adhesion on the back of the belt. The transmission capacity in this case is 11.2 Ps. The test was performed at room temperature. The pulleys 11 and 12 used were flat crown pulleys shown in FIG. This pulley has a crown center diameter D1 of 70 mm and a crown end diameter D2 of 68 m.
m, the diameter D3 of the flange is 71 mm.

FIG. 5 shows an embodiment of the heat resistant running test. That is, the test belt 13 is hung on the driving pulley 14, the driven pulley 15, and the idlers 16 and 17, and
Give a weight SW of 5 kgf and set the drive pulley 14 to 8
The motor was driven to rotate at 50 rpm, and the running time until the belt was damaged was examined. Test temperature is 85 ± 3 ℃, transmission capacity is 16
The winding angle of the test belt with respect to Ps and each of the idlers 16 and 17 is 90 degrees. The drive and driven pulleys 14 and 15 have a diameter of 120 mm, the idler 16 has a diameter of 55 mm, and the rear idler 17 is a flat crown pulley shown in FIG.

[0025]

[Table 1]

The test results are shown in Table 1. According to the table, the rubber hardness increases as the compounding amount of carbon increases, and the ML value (minimum torque (kg · cm) on the vulcanization curve obtained from the vulcanization test) is also basic. It can be seen that it corresponds to the carbon content. Where t
10 (time until the torque reaches 10% higher than the difference between the minimum torque value ML and the maximum torque value MH in the vulcanization curve) is a comparison between samples C and D,
As is clear from the comparison between the samples B and F, it is found that the use of a large amount of FEF carbon as the soft carbon is shorter even with the same amount of carbon, and is therefore advantageous in workability.

Looking at the adhesion on the back of the belt and the heat resistant running time, when the rubber hardness is low, it is easy to cause sticking, and when the rubber hardness is high, the heat resistant running time is shortened. It is understood that the range of 77 to 90 ° is preferable, and for that purpose, the amount of the carbon is preferably set to about 40 to 80 parts by weight. Note that Sample G could not be used as a belt due to difficulties in processing.

The above embodiment is an example in which the outer fabric rubber composite has a back rubber layer. However, without forming the back rubber layer, the impregnated rubber of the outer fabric forms the belt back surface (impregnated rubber). Is exposed on the back side of the belt), the impregnated rubber has a composition of 40 to 80 parts by weight of carbon and a rubber hardness of 77 to 90 ° as in the case of the back side rubber layer.

[Brief description of the drawings]

FIG. 1 is a sectional view of a V-ribbed belt according to an embodiment of the present invention.

FIG. 2 is an enlarged view of an envelope rubber composite used for the V-ribbed belt.

FIG. 3 is a front view showing a mode of an adhesion test on the back surface of the belt.

FIG. 4 is a cross-sectional view of the flat crown pulley with a part omitted.

FIG. 5 is a front view showing a mode of a heat resistant running test of the belt.

FIG. 6 is a partial cross-sectional perspective view showing a state in which an eraser-slag-like sticky substance is formed on the back surface of the belt by abrasion powder of rubber;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Top rubber 2 Bottom rubber 3 Adhesive rubber 4 Core body 5 V-shaped groove 6 Outer canvas rubber composite 7 Outer canvas impregnated with rubber 8 Back rubber layer 9 Back rubber layer 10 Adhesive rubber layer

Claims (3)

[Claims] An upper rubber, a bottom rubber, and a core provided between the upper rubber and the bottom rubber, extending in a belt longitudinal direction and fixed by an adhesive rubber, wherein the bottom rubber has a plurality of cores. In the V-ribbed belt in which the V-shaped groove is continuously formed in the longitudinal direction of the belt, and the upper rubber is covered with the envelope rubber composite, the envelope rubber composite is impregnated or coated with the rubber. And an outer covering cloth provided so that the rubber forms the back surface of the V-ribbed belt; and an adhesive rubber layer provided on the back side of the outer covering cloth and adhering the outer covering rubber composite to the upper rubber. The rubber forming the back surface of the belt is CR polymer 100
40 to 80 parts by weight of carbon is blended with respect to parts by weight, and the hardness specified by JIS-A is 77 to 90 °.
A V-ribbed belt, characterized in that: 2. The V-ribbed belt according to claim 1, wherein the outer covering rubber composite comprises a rubber-impregnated outer cloth, and a back surface of the V-ribbed belt applied to the surface of the outer cloth. A back rubber layer to be formed, a back rubber layer applied to the back of the outer canvas, and an adhesive rubber layer provided on the back rubber layer and bonding the outer fabric rubber composite to the upper rubber. The rubber of the back rubber layer is characterized in that 40 to 80 parts by weight of carbon is blended with respect to 100 parts by weight of CR polymer, and the hardness specified by JIS-A is 77 to 90 °. V-ribbed belt. 3. The V-ribbed belt according to claim 1, wherein a part of the carbon is made of soft carbon.