WO2018139578A1

WO2018139578A1 - Transmission v-belt and manufacturing method therefor

Info

Publication number: WO2018139578A1
Application number: PCT/JP2018/002458
Authority: WO
Inventors: 浩平 ▲濱▼本; 西村　年弘
Original assignee: 三ツ星ベルト株式会社
Priority date: 2017-01-26
Filing date: 2018-01-26
Publication date: 2018-08-02

Abstract

Provided is a transmission V-belt with a V-shaped cross section orthogonal to a belt circumferential direction, the belt having a friction transmission surface on both sides thereof in the belt width direction. The belt comprises: a rubber layer composed of a rubber composition; core fibers embedded in the rubber layer along the belt circumferential direction; and at least one reinforcing layer embedded in the rubber layer. The reinforcing layer includes a plurality of reinforcing fiber filaments having the same length as the belt width and does not include fibers crossing the belt width direction, or when such fibers are included, the weight, per unit area, of the fibers crossing the belt width direction is 30% or less of the weight of the reinforcing fiber filaments. The reinforcing layer has a structure in which the reinforcing fiber filaments are spread in a sheet shape, while being aligned in the belt with direction, and bonded in a non-twisted state. The reinforcing layer has a thickness of 0.05-0.5 mm.

Description

Transmission V-belt and manufacturing method thereof

The present invention relates to a transmission V-belt having a V-shaped cross section perpendicular to the belt circumferential direction and having friction transmission surfaces on both sides in the belt width direction, and a method for manufacturing the same.

The transmission V-belt includes a low-edge V-belt whose friction transmission surface is rubber, and a wrapped V-belt whose friction transmission surface is covered with a cover cloth. Depending on the application, it is properly used depending on the difference (coefficient of friction, etc.). These power transmission V-belts are used in a wide range of fields such as automobiles, agricultural machinery, and industrial machinery.

In recent years, automobile engines are required to be small and have high output. For this reason, transmission V-belts used in automobiles are required to have improved flexibility so as to cope with the downsizing of pulleys, and to improve side pressure resistance so that power can be transmitted with a high load.

Also, the agricultural machinery has been enlarged to accommodate large-scale agriculture. The belt mechanism of a large agricultural machine is continuously operated for a long time with high load and high tension. Moreover, the belt mechanism of a large agricultural machine has many multi-axis layouts. For this reason, transmission V-belts used for large-scale agricultural machines are required to have improved side pressure resistance and to have good flexibility that can be applied to multi-axis layouts.

As described above, the transmission V-belt is required to have both high side pressure resistance and high flexibility. Insufficient lateral pressure resistance causes the belt to fall into the pulley and cause buckling deformation called dishing, resulting in heat generation of the belt and separation between belt components, resulting in a reduction in belt life. Further, when the flexibility is lowered, heat generated by the bending when the belt is wound around or separated from the pulley is increased, and the constituent members of the belt such as rubber are thermally deteriorated, leading to a reduction in belt life.

Therefore, various methods have been proposed as means for improving the lateral pressure resistance while maintaining good flexibility. For example, in Patent Document 1, short fibers oriented in the belt width direction are embedded in a dispersed manner in the compressed rubber layer of the belt. Further, in Patent Document 2, a transverse cord is embedded in the compressed rubber layer. The horizontal blind cord is a cord in which aramid fibers or the like are arranged along the belt width direction and connected with fine yarns. Moreover, in patent document 3, the reinforcement layer which consists of fiber reinforced resin is embed | buried under the compression rubber layer. This reinforcing layer includes carbon fibers oriented in the belt width direction.

Japanese Patent Publication No. 5-63656 Japanese Patent Publication No.59-7859 Japanese Unexamined Patent Publication No. 2010-196889

However, the transmission V-belts as in Patent Documents 1 to 3 have problems such as a decrease in flexibility, insufficient side pressure resistance, and an increase in belt temperature.

In the method of blending short fibers as in Patent Document 1, the orientation of the short fibers is likely to be disturbed, and it is difficult to sufficiently enhance the orientation in the belt width direction. If the orientation in the belt width direction is low, sufficient lateral pressure resistance cannot be ensured. If the amount of short fibers can be increased, the amount of short fibers oriented in the belt width direction can be secured even if the orientation is disturbed, but the amount of short fibers is limited from the viewpoint of workability. Further, when the orientation of the short fibers is disturbed, the flexibility of the belt is lowered by the short fibers oriented in the belt circumferential direction. When the flexibility is lowered, heat generation due to the bending is likely to occur, so the belt temperature during running increases, and the life of the belt is shortened due to thermal deterioration of the rubber.

Moreover, the horizontal cord disclosed in Patent Document 2 uses a twisted cord in which fibers are twisted as a cord arranged along the belt width direction. If there is a twist, stretchability is imparted, and thus the lateral pressure resistance tends to be reduced. In addition, the filaments that are spiraled by twisting are not strictly oriented in the belt width direction, and thus the side pressure resistance is not sufficiently improved. Further, the twisted cord tends to generate heat due to friction between fibers when the belt is bent. As a result, the belt temperature during running increases, and the belt life may be shortened due to thermal deterioration of the rubber. Moreover, since a twisted cord is used, the thickness of the reinforcing layer is increased, and the flexibility may be lowered.

Further, in the method of embedding a reinforcing layer made of fiber reinforced resin in the compressed rubber layer as in Patent Document 3, the orientation in the belt width direction can be improved and the lateral pressure resistance is improved as compared with the case where short fibers are blended. it can. However, Patent Document 3 does not describe whether the fiber constituting the fiber reinforced resin has a twist. Therefore, in Patent Document 3, it is unclear whether heat generation due to friction between fibers of the fiber reinforced resin is difficult to occur. Moreover, in patent document 3, nothing is prescribed | regulated about the thickness of a reinforcement layer.

An object of the present invention is to provide a transmission V-belt that can improve the lateral pressure resistance while suppressing the heat generation of the belt and a decrease in flexibility, and a method for manufacturing the same.

The transmission V-belt according to the first aspect of the present invention is a transmission V-belt having a V-shaped cross section perpendicular to the belt circumferential direction and having friction transmission surfaces on both sides in the belt width direction. A rubber layer, a core wire embedded in the rubber layer along the circumferential direction of the belt, and at least one reinforcing layer embedded in the rubber layer, wherein the reinforcing layer has the same length as the belt width. A plurality of reinforcing fiber filaments having no or no fibers crossing in the belt width direction, or when included, the weight per unit area of the fibers crossing in the belt width direction is 30% or less of the reinforcing fiber filaments And the reinforcing layer has a structure in which the reinforcing fiber filaments are untwisted and bonded in a sheet shape while being oriented in the belt width direction, and the thickness of the reinforcing layer is 0.05. ~ 0.5mm , Drive V-belt.

According to this configuration, a large number of reinforcing fiber filaments are embedded in the rubber layer as a reinforcing layer in a state where the reinforcing fiber filaments are expanded in a sheet shape while being oriented in the belt width direction. Therefore, the side pressure resistance of the transmission V-belt can be improved as compared with a case where no reinforcing layer is provided or short fibers oriented in the belt width direction are embedded in the rubber layer in a dispersed manner. Furthermore, since a large number of reinforcing fiber filaments constituting the reinforcing layer are spread and joined in a sheet shape, disorder of the orientation of the reinforcing fiber filaments can be prevented. Thereby, the side pressure resistance can be improved more reliably. By improving the lateral pressure resistance, the life of the transmission V-belt can be extended.
In addition, the reinforcing layer does not contain any fiber that intersects the belt width direction, or contains only 30% or less of the weight per unit area of the reinforcing fiber filament. Therefore, it is possible to ensure substantially the same flexibility as when no reinforcing layer is provided. That is, it is possible to suppress a decrease in the flexibility of the transmission V-belt. Moreover, the reinforcing fiber filament is embedded in a non-twisted state, whereby the thickness of the reinforcing layer can be reduced while ensuring high lateral pressure resistance. Thereby, the fall of a flexibility can be suppressed more. In the present invention, “non-twisted” means that the number of twists is 1/10 cm or less.
Further, since the reinforcing fiber filament is embedded in a non-twisted state, heat generation due to friction between the fibers hardly occurs during bending. Further, by suppressing the lowering of the flexibility, it is possible to suppress the heat generation of the belt due to the bending when the belt is wound around or separated from the pulley. Therefore, an increase in belt temperature during traveling can be suppressed. By suppressing the increase in belt temperature, the transmission V-belt can be extended.
The thickness of the reinforcing layer is 0.05 to 0.5 mm. If the thickness of the reinforcing layer exceeds 0.5 mm, the flexibility may be reduced, and heat generation of the belt due to the bending may increase. In the present invention, by reducing the thickness of the reinforcing layer to 0.5 mm or less, it is possible to reliably suppress a decrease in flexibility and heat generation of the belt. Further, if the thickness of the reinforcing layer is less than 0.05 mm, sufficient lateral pressure resistance may not be ensured. In the present invention, since the effect of improving the side pressure resistance by the untwisted reinforcing fiber filament is high, sufficient side pressure resistance can be ensured even if the reinforcing layer is as thin as 0.05 to 0.5 mm. In the present invention, the “thickness of the reinforcing layer” refers to the thickness of each reinforcing layer even when there are a plurality of reinforcing layers.
Further, since the reinforcing fiber filaments are spread and bonded in a sheet shape and do not come apart, handling of the reinforcing layer is easy during belt manufacture. Specifically, it is possible to easily perform an operation of winding a sheet serving as a reinforcing layer on unvulcanized rubber and an operation of applying an adhesive treatment such as an RFL process or a rubber paste process to the reinforcing layer.

In the transmission V-belt of the second aspect, the tensile elastic modulus of the reinforcing fiber filament is 200 to 600 GPa in the first aspect.

When the tensile elastic modulus of the reinforcing fiber filament is less than 200 GPa, sufficient lateral pressure resistance may not be ensured. In the present invention, when the tensile elastic modulus of the reinforcing fiber filament is 200 GPa or more, sufficient lateral pressure resistance can be ensured while reducing the thickness of the reinforcing layer and suppressing a decrease in flexibility.
On the other hand, if the tensile elastic modulus of the reinforcing fiber filament exceeds 600 GPa, it becomes difficult for the reinforcing fiber filament to follow the deformation of the belt, it becomes easy to peel between the reinforcing layer and the rubber composition, and the belt life is shortened. In the present invention, when the tensile elastic modulus of the reinforcing fiber filament is 600 GPa or less, peeling between the reinforcing layer and the rubber composition can be suppressed, and the belt can have a longer life.

In the transmission V-belt of the third aspect, in the first or second aspect, the thermal conductivity of the reinforcing fiber filament is 5.0 W / (m · K) or more.

According to this configuration, heat generated in the belt due to bending and friction can be efficiently diffused into the air and pulley through the reinforcing fiber filament having high thermal conductivity. Thereby, an increase in belt temperature can be suppressed, and the life of the transmission V-belt can be further extended.

In the transmission V-belt of the fourth aspect, in any one of the first to third aspects, the reinforcing fiber filament is a carbon fiber.

According to this configuration, since the reinforcing fiber filament is a carbon fiber, the tensile elastic modulus of the reinforcing fiber filament can be within the range of the second invention. Therefore, the same effect as the second invention can be obtained. Moreover, since the reinforcing fiber filament is a carbon fiber, the thermal conductivity of the reinforcing fiber filament can be within the numerical range of the third invention. Therefore, the same effect as the third invention can be obtained.

In the fifth aspect of the transmission V-belt, in any of the first to fourth aspects, one reinforcing layer is embedded on each side of the core wire in the rubber layer.

According to this configuration, the side pressure resistance can be further improved by the presence of the reinforcing layers on both sides of the core wire. Therefore, even if the transmission V-belt is used under a high load condition, the life can be extended.

In the transmission V-belt according to a sixth aspect, in any one of the first to fifth aspects, the rubber layer is different from an adhesive rubber layer in which at least a part of the core wire is embedded, and the adhesive rubber layer. A compressed rubber layer made of a rubber composition and provided on the inner peripheral side of the adhesive rubber layer, and a stretched rubber made of a rubber composition different from the adhesive rubber layer and provided on the outer peripheral side of the adhesive rubber layer The reinforcing layer is embedded between at least one of the adhesive rubber layer and the compressed rubber layer and between the adhesive rubber layer and the stretched rubber layer.

According to this configuration, the reinforcing layer is in contact with the adhesive rubber layer in which the core wire is embedded. That is, the reinforcing layer is embedded at a position close to the core wire. The transmission V-belt is required to have higher lateral pressure resistance as it is closer to the core wire in the belt thickness direction. Therefore, by embedding the reinforcing layer at a position close to the core wire, sufficient lateral pressure resistance can be ensured by the thinner reinforcing layer. Since the thickness of the reinforcing layer is thin, a decrease in flexibility can be further suppressed.
Further, when the reinforcing layer is embedded in the compressed rubber layer (or the stretched rubber layer), it is necessary to dispose the reinforcing layer between the two rubber sheets forming the compressed rubber layer (or the stretched rubber layer) at the time of manufacture. is there. In the present invention, since the reinforcing layer is embedded between the compressed rubber layer or the stretched rubber layer and the adhesive rubber layer, the belt is manufactured as compared with the case where the reinforcing layer is embedded in the compressed rubber layer or the stretched rubber layer. Can reduce the man-hours required.

In the transmission V-belt according to a seventh aspect, in any one of the first to fifth aspects, the rubber layer is different from the adhesive rubber layer in which at least a part of the core wire is embedded, and the adhesive rubber layer A compressed rubber layer made of a rubber composition and provided on the inner peripheral side of the adhesive rubber layer, and a stretched rubber made of a rubber composition different from the adhesive rubber layer and provided on the outer peripheral side of the adhesive rubber layer The reinforcing layer is embedded in at least one of the compressed rubber layer and the stretched rubber layer.

構成 According to this configuration, buckling deformation due to dishing is reduced, and heat generation of the belt and separation between components can be suppressed. Therefore, the life of the transmission V-belt can be further extended.

The transmission V-belt according to an eighth aspect is any one of the first to fifth aspects, wherein the rubber layer is composed of a compressed rubber layer and a rubber composition different from the compressed rubber layer, and the compressed rubber layer The stretched rubber layer provided on the belt outer peripheral side, and the core wire is embedded between the compressed rubber layer and the stretched rubber layer, in the compressed rubber layer, or in the stretched rubber layer. The reinforcing layer is embedded in at least one of the compressed rubber layer, the stretched rubber layer, and the compressed rubber layer and the stretched rubber layer.

According to this configuration, since it is not necessary to provide an adhesive rubber layer, it is possible to reduce the man-hours required for belt manufacture.

The transmission V-belt of the ninth aspect is any one of the sixth to eighth aspects, wherein the core wire is not embedded in the compressed rubber layer, and the compressed rubber layer includes short fibers. The amount of the short fibers in the compressed rubber layer is 0.1 to 10 parts by mass with respect to 100 parts by mass of the rubber component.

When the blending amount of the short fibers blended in the compressed rubber layer exceeds 10 parts by mass with respect to 100 parts by mass of the rubber component, the flexibility decreases and the adhesiveness between the compressed rubber layer and the adjacent layer decreases. Therefore, cracks are likely to occur in the rubber. In the present invention, the blending amount of the short fibers blended in the compressed rubber layer is 10 parts by mass or less with respect to 100 parts by mass of the rubber component, so that a decrease in flexibility and adhesiveness can be minimized. Generation of cracks can be suppressed. Therefore, the life of the transmission V-belt can be further extended.
Moreover, when the compounding quantity of the short fiber mix | blended with a compression rubber layer is less than 0.1 mass part with respect to 100 mass parts of rubber components, side pressure resistance may be insufficient and a belt life may become short. In the present invention, since the effect of improving the side pressure resistance by the reinforcing layer is high, the amount of the short fiber blended in the compressed rubber layer is as small as 0.1 to 10 parts by mass with respect to 100 parts by mass of the rubber component. Even if it is, sufficient lateral pressure resistance can be secured.

A transmission V-belt according to a tenth aspect is the transmission V-belt according to any one of the sixth to ninth aspects, wherein the reinforcing layer is embedded in or in contact with the compressed rubber layer. When the layer includes chloroprene rubber and the reinforcing layer is in contact with the adhesive rubber layer, the adhesive rubber layer includes chloroprene rubber.

According to this configuration, the compression rubber layer (and the adhesive rubber layer) includes chloroprene rubber having a good balance of physical properties such as heat resistance, wear resistance, and weather resistance, thereby improving the durability of the transmission V-belt. . Moreover, since the adhesive force between the reinforcing layer and the compressed rubber layer (and the adhesive force between the reinforcing layer and the adhesive rubber layer) can be improved and peeling between them can be suppressed, the transmission V-belt Longer life can be achieved. Furthermore, since chloroprene rubber is relatively inexpensive, it is excellent in economic efficiency.

The transmission V-belt according to an eleventh aspect is the transmission V-belt according to any one of the first to tenth aspects, wherein the reinforcing layer is composed of one or a plurality of laminated unidirectional fiber sheets, The sheet has a structure in which the reinforcing fiber filaments are bonded to each other by a thermosetting resin.

According to this configuration, the adhesiveness between the reinforcing fiber filament and the rubber composition is improved by the thermosetting resin, so that the life of the transmission V-belt can be extended.

The transmission V-belt according to a twelfth aspect is the transmission V-belt according to any one of the first to tenth aspects, wherein the reinforcing layer comprises one or a plurality of laminated unidirectional fiber sheets, and the unidirectional fiber The sheet has a structure in which the reinforcing fiber filaments are bonded to each other by an auxiliary yarn that intersects the belt width direction and has a weight per unit area of 30% or less of the reinforcing fiber filaments.

When reinforcing fiber filaments are bonded with a resin, the flexibility of the belt may be lowered depending on the type and thickness of the resin. In this aspect, since the reinforcing fiber filaments are bound by the auxiliary yarn, it is easy to suppress a decrease in flexibility. Also, compared to the case where reinforcing fiber filaments are bonded with resin, the unidirectional fiber sheet is torn when a strong force is applied to the unidirectional fiber sheet in the belt circumferential direction during adhesion processing or molding. Hateful.
In the present invention, “reinforcing fiber filaments are joined together by auxiliary yarn” means, for example, that a unidirectional fiber sheet is woven by a fiber bundle made of a plurality of reinforcing fiber filaments and auxiliary yarns. Including cases.

In the transmission V-belt of the thirteenth aspect according to the eleventh or twelfth aspect, the basis weight amount of the unidirectional fiber sheet including the thermosetting resin or the auxiliary yarn is 50 to 400 g / m ² .

If the basis weight of the unidirectional fiber sheet is less than 50 g / m ² , the number of unidirectional fiber sheets constituting the reinforcing layer necessary to ensure sufficient lateral pressure resistance increases, and the number of man-hours required for belt manufacture Will increase. In the present invention, since the basis weight of the unidirectional fiber sheet is 50 g / m ² or more, sufficient lateral pressure resistance can be ensured by the reinforcing layer composed of one or a small number of unidirectional fiber sheets.
Further, when the basis weight of the unidirectional fiber sheet exceeds 400 g / m ² , even if the reinforcing layer is composed of one unidirectional fiber sheet, the reinforcing layer becomes too thick and bent. May decrease. In this invention, since the fabric weight of a unidirectional fiber sheet is 400 g / m < ² > or less, the fall of a flexibility can be suppressed.

A method for manufacturing a transmission V-belt according to a fourteenth aspect of the present invention is a method for manufacturing the transmission V-belt according to the first aspect, wherein the reinforcing fiber filaments are bonded to each other or laminated. After laminating a plurality of the unidirectional fiber sheets thus formed as one reinforcing layer on a first unvulcanized rubber layer that forms a part of the rubber layer, another portion of the rubber layer is formed thereon. A laminating step of laminating a second unvulcanized rubber layer to form a rubber layer, and a vulcanizing step of vulcanizing the first unvulcanized rubber layer and the second unvulcanized rubber layer to form the rubber layer. Including.

According to this method, the conventional method of manufacturing a conventional transmission V-belt can be used as it is, and the manufacturing process can be prevented from becoming complicated. Furthermore, it is possible to embed a reinforcing layer at an arbitrary position from the belt inner surface side to the outer surface side, and it is possible to reinforce a place where the side pressure resistance is particularly desired to be enhanced.

According to a fifteenth aspect of the invention, in the fourteenth aspect, the unidirectional fiber sheet is manufactured by at least one of RFL treatment, rubber paste treatment, and resin impregnation treatment before the lamination step. Adhesive components are adhered to the surface.

According to this method, since the adhesive force between the reinforcing fiber filament and the rubber composition is increased, peeling between the reinforcing layer and the rubber layer can be prevented, and the power transmission V-belt can have a longer life.
In addition, since the reinforcing fiber filaments are more firmly bonded to each other by the adhesive component, it is possible to more reliably prevent the disorder of the orientation of the reinforcing fiber filaments.

In the present invention, the cross section perpendicular to the belt circumferential direction being V-shaped means that two side surfaces are arranged on two straight lines forming a V shape in the cross section perpendicular to the belt circumferential direction. . The cross section perpendicular to the belt circumferential direction of the transmission V-belt of the present invention may be rectangular, hexagonal or otherwise as long as it is V-shaped. In the present specification, 1 to 10 means 1 or more and 10 or less. This definition also applies to numerical values other than 1 and 10.

FIG. 1 is a cross-sectional view of a transmission V-belt according to an embodiment of the present invention. FIG. 2 is a cross-sectional perspective view of the belt main body of the transmission V-belt. FIG. 3 is a cross-sectional view of the reinforcing layer. FIG. 4 is a perspective view for explaining the manufacturing procedure of the transmission V-belt. FIG. 5 is a cross-sectional view of the V-belt for transmission in the middle of manufacturing. (A) and (b) of Drawing 6 is a top view of a unidirectional fiber sheet of a modification. FIG. 7 is a cross-sectional perspective view of a transmission V-belt according to a modified example. FIG. 8A is a cross-sectional view in the process of manufacturing the transmission V-belt of the modified example, and FIG. 8B is a cross-sectional view of the transmission V-belt. FIG. 9A is a cross-sectional view in the middle of manufacturing the transmission V-belt of the modified example, and FIG. 9B is a cross-sectional view of the transmission V-belt. FIG. 10A is a cross-sectional view in the process of manufacturing the transmission V-belt of the modified example, and FIG. 10B is a cross-sectional view of the transmission V-belt. FIG. 11A is a cross-sectional view in the middle of manufacturing a transmission V-belt of a modified example, and FIG. 11B is a cross-sectional view of the transmission V-belt. FIG. 12 is a cross-sectional perspective view of a transmission V-belt of a modified example. FIG. 13 is a diagram illustrating a side pressure resistance test. FIG. 14 is a diagram for explaining the flexibility test.

Next, the transmission V-belt 1 according to the embodiment of the present invention will be described. In the following description, the belt circumferential direction (belt longitudinal direction), the belt width direction, the belt thickness direction, the belt outer circumferential side, and the belt inner circumferential side are directions shown in FIG. As shown in FIG. 1, the transmission V-belt 1 has a V-shaped cross section perpendicular to the belt circumferential direction. The belt inner peripheral side is the narrow side, and the belt outer peripheral side is the wide side. The transmission V-belt 1 is annular and is used by being wound around at least two pulleys 100 (drive pulley and driven pulley) having a V-shaped groove 101 (hereinafter referred to as V-groove 101). The transmission V-belt 1 has

friction transmission surfaces

1a and 1b on both sides in the belt width direction. The

friction transmission surfaces

1 a and 1 b are in contact with the V groove 101 of the pulley 100. Power is transmitted between the transmission V-belt 1 and the pulley 100 by the frictional force due to this contact.

The transmission V-belt 1 is a wrapped V-belt, and has a belt body 2 and a cover cloth 3 that covers the entire circumference of the belt body 2. The cover cloth 3 is a woven cloth woven with warps and wefts made of synthetic fibers such as polyester, polyamide, aramid, and vinylon, and natural fibers such as cotton.

As shown in FIG. 2, the belt main body 2 includes a rubber layer 4, a core wire 5 embedded in the rubber layer 4, and two reinforcing layers 6 embedded in the rubber layer 4. The two reinforcing layers 6 are embedded on both sides of the core wire 5 in the rubber layer 4. The rubber layer 4 includes an adhesive rubber layer 7 in which a core wire 5 is embedded, a compression rubber layer 8, and an extension rubber layer 9. The compression rubber layer 8 is provided on the belt inner peripheral side of the adhesive rubber layer 7. The compressed rubber layer 8 is compressed in the belt circumferential direction when the transmission V-belt 1 is wound around the pulley 100 and traveled. The stretch rubber layer 9 is provided on the belt outer peripheral side of the adhesive rubber layer 7. The stretch rubber layer 9 is stretched in the belt circumferential direction when the transmission V-belt 1 is wound around the pulley 100 and traveled. The thickness of the compressed rubber layer 8 is larger than the thickness of the stretched rubber layer 9. The two reinforcing layers 6 are provided between the adhesive rubber layer 7 and the compressed rubber layer 8 and between the adhesive rubber layer 7 and the stretched rubber layer 9, respectively. That is, the two reinforcing layers 6 are embedded at positions close to the core wire 5 of the rubber layer 4.

The adhesive rubber layer 7, the compressed rubber layer 8, and the stretch rubber layer 9 are composed of a rubber composition. The rubber composition constituting the adhesive rubber layer 7 is different from the rubber composition constituting the compressed rubber layer 8 and the rubber composition constituting the stretched rubber layer 9. The rubber composition constituting the adhesive rubber layer 7 has higher adhesion to the core wire 5 and the reinforcing layer 6 than the rubber composition constituting the compressed rubber layer 8 and the rubber composition constituting the stretched rubber layer 9. The rubber composition constituting the stretched rubber layer 9 and the rubber composition constituting the compressed rubber layer 8 may be the same or different.

As the rubber component of the rubber composition, vulcanizable or crosslinkable rubber is used. Specifically, for example, diene rubber (natural rubber, isoprene rubber, butadiene rubber, chloroprene rubber, styrene butadiene rubber, acrylonitrile butadiene rubber, hydrogenated nitrile rubber, etc.), ethylene-α-olefin elastomer, chlorosulfonated polyethylene rubber Alkylated chlorosulfonated polyethylene rubber, epichlorohydrin rubber, acrylic rubber, silicone rubber, urethane rubber, fluororubber, and the like. These rubber components can be used alone or in combination of two or more. The compressed rubber layer 8 and the adhesive rubber layer 7 preferably contain chloroprene rubber.

The rubber composition may include a vulcanizing agent or a crosslinking agent, a co-crosslinking agent, a vulcanization aid, a vulcanization accelerator, a vulcanization retarder, a metal oxide (zinc oxide, magnesium oxide, calcium oxide, Barium oxide, iron oxide, copper oxide, titanium oxide, aluminum oxide, etc.), reinforcing agent (carbon black, silicon oxide such as hydrous silica), short fiber, filler (clay, calcium carbonate, talc, mica, etc.), softening Agents (paraffin oil, oils such as naphthenic oil), processing agents or processing aids (stearic acid, metal stearate, wax, paraffin, etc.), anti-aging agents (antioxidants, thermal anti-aging agents, bending) Anti-cracking agent, anti-ozone degradation agent, etc.), colorant, tackifier, plasticizer, coupling agent (silane coupling agent, etc.), stabilizer (ultraviolet absorber, heat stabilizer, etc.), flame retardant, antistatic It may be blended agent. In addition, you may mix | blend a metal oxide as a crosslinking agent.

The rubber composition constituting the compressed rubber layer 8 may contain short fibers. The amount of short fibers in the compressed rubber layer 8 is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the rubber component. The rubber composition constituting the stretched rubber layer 9 may contain short fibers. The rubber composition constituting the adhesive rubber layer 7 does not contain short fibers.

The core wire 5 extends in the belt circumferential direction and is buried with a certain interval in the belt width direction. The core wire 5 is made of a twisted cord (multi-twisted, single-twisted, rung-twisted, etc.) using a multifilament yarn. The material of the core wire 5 is, for example, a synthetic fiber such as an aramid fiber or an inorganic fiber such as a carbon fiber. The core 5 may be subjected to an adhesion treatment with an RFL solution or the like for the purpose of enhancing the adhesion with the adhesive rubber layer 7.

The reinforcing layer 6 is composed of a single unidirectional fiber sheet 10. The reinforcing layer 6 may be composed of a plurality of unidirectional fiber sheets 10 stacked in the belt thickness direction. As shown in FIG. 3, the unidirectional fiber sheet 10 has a large number of reinforcing fiber filaments 11 extending in a sheet shape while being oriented in the belt width direction. For example, the density in the belt circumferential direction of the fiber reinforcing filaments 11 in the unidirectional fiber sheet 10 may be about 1 × 10 ⁹ to 1 × 10 ¹¹ pieces / 5 cm. Each reinforcing fiber filament 11 has the same length as the belt width. The reinforcing fiber filament 11 is arranged in a non-twisted state.

The reinforcing fiber filaments 11 are bonded together by a thermosetting resin 12. The thermosetting resin 12 is impregnated in the reinforcing fiber filament 11. As the thermosetting resin 12, for example, an epoxy resin, a phenol resin, a melamine resin, a urea resin, a polyurethane resin, or the like can be used, and among them, an epoxy resin is preferable. The reinforcing layer 6 does not include fibers that intersect in the belt width direction.

The reinforcing layer 6 has a thickness of 0.05 to 0.5 mm. 1 and 2 show the thickness of the reinforcing layer 6 in an exaggerated manner. The thickness of the reinforcing layer 6 includes the thickness of the thermosetting resin 12 that covers the periphery of the reinforcing fiber filament 11. The basis weight of the unidirectional fiber sheet 10 including the thermosetting resin 12 is preferably 50 to 400 g / m ² . The thickness of the reinforcing fiber filament 11 is not particularly limited, but is, for example, about 0.1 to 50 μm, and preferably about 5 to 25 μm. If the fiber diameter is too thin, handling becomes difficult, and if it is too thick, the flexibility of the belt may be lowered. The tensile elastic modulus (Young's modulus) of the reinforcing fiber filament 11 is preferably 200 to 600 GPa. The thermal conductivity of the reinforcing fiber filament 11 is preferably 5.0 W / (m · K) or more. The upper limit of the thermal conductivity of the reinforcing fiber filament 11 is not particularly limited, but may be about 20 W / (m · K).

The type of fiber of the reinforcing fiber filament 11 is not particularly limited, and examples thereof include carbon fiber, glass fiber, aramid fiber, polyamide fiber, and polyester fiber. Of these, carbon fibers are particularly preferred because of their high tensile modulus and thermal conductivity. The type of fiber of the reinforcing fiber filament 11 constituting the unidirectional fiber sheet 10 may be one type or plural types. Specific examples of the unidirectional fiber sheet 10 include “Toray Capri Preg” manufactured by Toray Industries, Inc. and “Pyrofil” manufactured by Mitsubishi Rayon Co., Ltd., for example. The configuration of the two reinforcing layers 6 may be the same or different.

The adhesion component (not shown) may adhere to the reinforcement layer 6 by the adhesion process for improving adhesiveness with the surrounding rubber layer 4 (adhesive rubber layer 7). Even without performing the adhesion treatment, the thermosetting resin 12 covering the surface of the reinforcing fiber filament 11 can ensure the adhesion to the rubber layer 4, but in order to further improve the adhesion, the adhesion treatment may be performed. preferable. Examples of the bonding process include an RFL process and a rubber paste process (soaking process). In the RFL treatment, the unidirectional fiber sheet 10 or the unidirectional fiber sheet 10 before forming the unidirectional fiber sheet 10 is dipped in the RFL solution and then heat-treated, so that the unidirectional fiber sheet 10 or the unidirectional fiber sheet is treated. 10 is a process of adhering an adhesive component to the reinforcing fiber filament 11 before the formation of 10. The RFL liquid is a mixture of resorcin and formalin condensate in latex. Styrene / butadiene / vinylpyridine terpolymer, hydrogenated nitrile rubber, chlorosulfonated polyethylene, epichlorohydrin, etc. are used as latex. It is done. In the rubber paste treatment, an unvulcanized rubber composition dissolved in a solvent to form a rubber paste is applied to the surface of the unidirectional fiber sheet 10, and then the solvent is evaporated to remove the unidirectional fiber sheet 10. This is a treatment for forming a film (adhesive component) of the unvulcanized rubber composition on the surface. The rubber paste treatment may be performed after the adhesion treatment using the RFL liquid.

Next, the manufacturing procedure of the transmission V-belt 1 will be described with reference to FIGS.
First, as shown in FIG. 4, an unvulcanized rubber sheet 118 constituting the compressed rubber layer 8 is wound around a cylindrical molding drum M. Further, the unidirectional fiber sheet 10 is wound so that the direction of the reinforcing fiber filament 11 is substantially parallel to the central axis direction of the forming drum M. The width of the unidirectional fiber sheet 10 to be wound (the length in the direction of the central axis of the forming drum M) is substantially the same as the width of the unvulcanized rubber sheet 118. The reinforcing fiber filament 11 of the unidirectional fiber sheet 10 is impregnated with a semi-cured thermosetting resin 12. The unidirectional fiber sheet 10 may be subjected to adhesion treatment such as RFL treatment or rubber paste treatment. In the case where the reinforcing layer 6 is constituted by a plurality of unidirectional fiber sheets 10, either of the following two methods may be adopted. The first method is a method in which a plurality of unidirectional fiber sheets 10 having the same width as the rubber sheet 118 and substantially the same length as the belt circumference are wound one by one. The second method is a method of winding a plurality of long unidirectional fiber sheets 10 having the same width as the rubber sheet 118 and a plurality of times the circumference of the belt.

Subsequently, an unvulcanized rubber sheet 117A (see FIG. 5) constituting a part of the adhesive rubber layer 7 is wound. Thereafter, one core wire 5 is wound in a spiral shape. Alternatively, a plurality of core wires 5 are wound at predetermined intervals. Next, after winding the unvulcanized rubber sheet 117 </ b> B (see FIG. 5) constituting the remaining portion of the adhesive rubber layer 7, the unidirectional fiber sheet 10 is wound as before. Thereafter, an unvulcanized rubber sheet 119 (see FIG. 5) constituting the stretched rubber layer 9 is wound to form an unvulcanized belt sleeve. At the time of vulcanization, the thermosetting resin 12 impregnated in the reinforcing fiber filament 11 is completely cured.

Next, the unvulcanized belt sleeve is cut into a predetermined width and cut so as to have a V-shaped cross section, and processed into an unvulcanized belt body 2. Thereafter, the belt body 2 is covered with the cover cloth 3 that has been subjected to the friction treatment to form an unvulcanized belt. Then, the unvulcanized belt is fitted into a molding die and heated and pressed to vulcanize (or crosslink). Thus, the transmission V-belt 1 is formed. The friction treatment uses a calender roll, and the unvulcanized rubber composition and the cover cloth 3 are simultaneously passed between rolls rotating at different surface speeds, so that the unvulcanized rubber is covered between the fibers of the cover cloth 3. This is a process of rubbing the rubber composition.

In the manufacturing procedure described above, the components are wound around the forming drum M in order from the components on the inner peripheral side of the transmission V-belt 1, but are wound around the molding die in order from the components on the outer peripheral side of the transmission V-belt 1. Also good.

According to the transmission V-belt 1 of the present embodiment, the following effects can be obtained.
In the transmission V-belt 1 of the present embodiment, a large number of reinforcing fiber filaments 11 are embedded in the rubber layer 4 as the reinforcing layer 6 in a state where the reinforcing fiber filaments 11 are spread in a sheet shape while being oriented in the belt width direction. Therefore, the lateral pressure resistance of the transmission V-belt 1 can be improved as compared with the case where the reinforcing layer 6 is not provided or the short fibers oriented in the belt width direction are embedded in the rubber layer 4 in a dispersed manner. Furthermore, since the many reinforcing fiber filaments 11 constituting the reinforcing layer 6 are spread and joined in a sheet shape, disorder of the orientation of the reinforcing fiber filaments 11 can be prevented. Thereby, the side pressure resistance can be improved more reliably. The life of the transmission V-belt 1 can be extended by improving the lateral pressure resistance.

Further, the reinforcing layer 6 does not contain any fiber that intersects the belt width direction. Therefore, substantially the same flexibility as when the reinforcing layer 6 is not provided can be secured. That is, it is possible to suppress a decrease in flexibility of the transmission V-belt 1. In addition, since the reinforcing fiber filament 11 is embedded in a non-twisted state, the thickness of the reinforcing layer 6 can be reduced while ensuring high lateral pressure resistance. Thereby, the fall of a flexibility can be suppressed more.
In addition, since the reinforcing fiber filament 11 is embedded in a non-twisted state, heat generation due to friction between fibers hardly occurs during bending. Further, by suppressing the lowering of the flexibility, it is possible to suppress the heat generation of the belt due to the bending when the belt is wound around or separated from the pulley. Therefore, an increase in belt temperature during traveling can be suppressed. By suppressing the increase in belt temperature, the transmission V-belt 1 can have a longer life.

The thickness of the reinforcing layer 6 is 0.05 to 0.5 mm, preferably 0.05 to 0.3 mm, more preferably 0.05 to 0.2 mm (especially 0.08 to 0.15 mm). When the thickness of the reinforcing layer 6 exceeds 0.5 mm, the flexibility is lowered, and the belt heat generation due to the bending may increase. By setting the thickness of the reinforcing layer 6 to 0.5 mm or less, it is possible to reliably suppress a decrease in flexibility and heat generation of the belt. Further, if the thickness of the reinforcing layer 6 is less than 0.05 mm, sufficient lateral pressure resistance may not be ensured. In this embodiment, since the effect of improving the lateral pressure resistance by the untwisted reinforcing fiber filament 11 is high, sufficient lateral pressure resistance is ensured even when the reinforcing layer 6 is as thin as 0.05 to 0.5 mm. it can.

Further, since the reinforcing fiber filaments 11 are spread and joined in a sheet shape and do not come apart, the handling of the reinforcing layer 6 is easy during belt manufacture. Specifically, the work of winding the unidirectional fiber sheet 10 for forming the reinforcing layer 6 on the unvulcanized rubber, or the adhesion of the reinforcing layer 6 (unidirectional fiber sheet 10) such as RFL treatment or rubber paste treatment. It is possible to easily perform the process of performing the processing.

If the tensile elastic modulus of the reinforcing fiber filament 11 is less than 200 GPa, sufficient lateral pressure resistance may not be ensured. The tensile elastic modulus of the reinforcing fiber filament 11 is preferably 200 GPa or more. As a result, sufficient lateral pressure resistance can be secured while reducing the thickness of the reinforcing layer 6 and suppressing a decrease in flexibility.
If the tensile elastic modulus of the reinforcing fiber filament 11 exceeds 600 GPa, it becomes difficult for the reinforcing fiber filament 11 to follow the deformation of the belt, it becomes easy to peel between the reinforcing layer 6 and the rubber composition, and the belt life is shortened. Become. The tensile elastic modulus of the reinforcing fiber filament 11 is preferably 600 GPa or less. Thereby, peeling between the reinforcing layer 6 and the rubber composition can be suppressed, and the life of the belt can be extended.

The thermal conductivity of the reinforcing fiber filament 11 is preferably 5.0 W / (m · K) or more. Thereby, the heat generated in the belt due to bending and friction can be efficiently diffused into the air and pulley through the reinforcing fiber filament 11 having high thermal conductivity. Therefore, an increase in belt temperature can be suppressed and the transmission V-belt 1 can have a longer life.

The reinforcing fiber filament 11 is preferably a carbon fiber. Thereby, the tensile elastic modulus of the reinforcing fiber filament 11 can be 200 to 600 GPa. Further, the thermal conductivity of the reinforcing fiber filament 11 can be set to 5.0 W / (m · K) or more.

Further, in this embodiment, the presence of the reinforcing layers 6 on both sides (belt outer peripheral side and belt inner peripheral side) of the core wire 5 can further improve the lateral pressure resistance. Therefore, even if the transmission V-belt 1 is used under a high load condition, the life can be extended.

In the present embodiment, the reinforcing layer 6 is in contact with the adhesive rubber layer 7 in which the core wire 5 is embedded. That is, the reinforcing layer 6 is embedded at a position close to the core wire 5. As the transmission V-belt 1 is closer to the core wire 5 in the belt thickness direction, higher lateral pressure resistance is required. Therefore, by embedding the reinforcing layer 6 at a position close to the core wire 5, sufficient lateral pressure resistance can be ensured by the thinner reinforcing layer 6. Since the thickness of the reinforcing layer 6 is thin, a decrease in flexibility can be further suppressed.
When the reinforcing layer 6 is embedded in the compressed rubber layer 8 (or the stretched rubber layer 9), the reinforcing layer is interposed between the two rubber sheets forming the compressed rubber layer 8 (or the stretched rubber layer 9) at the time of manufacture. 6 must be arranged. In the present embodiment, since the reinforcing layer 6 is embedded between the compressed rubber layer 8 and the adhesive rubber layer 7 and between the stretched rubber layer 9 and the adhesive rubber layer 7, the reinforcing layer 6 is compressed rubber layer. Compared to the case where the belt 8 or the stretched rubber layer 9 is embedded, the number of man-hours for manufacturing the belt can be reduced.

When the blending amount of the short fibers blended in the compressed rubber layer 8 exceeds 10 parts by mass with respect to 100 parts by mass of the rubber component, the flexibility is lowered and the adhesiveness between the compressed rubber layer 8 and the adjacent layer is reduced. Since it falls, it becomes easy to produce a crack in rubber. The blending amount of the short fibers blended in the compressed rubber layer 8 is preferably 10 parts by mass or less with respect to 100 parts by mass of the rubber component. Thereby, the fall of a flexibility and adhesiveness can be suppressed to the minimum, and generation | occurrence | production of a crack can be suppressed. Therefore, the life of the transmission V-belt 1 can be further extended.
Moreover, when the compounding quantity of the short fiber mix | blended with the compression rubber layer 8 is less than 0.1 mass part with respect to 100 mass parts of rubber components, side pressure resistance may be insufficient and a belt life may become short. The blending amount of the short fibers blended in the compressed rubber layer 8 is preferably 0.1 to 10 parts by weight, particularly preferably 0.1 to 5 parts by weight or less with respect to 100 parts by weight of the rubber component. Since the effect of improving the side pressure resistance by the reinforcing layer 6 is high, the amount of the short fibers blended in the compressed rubber layer 8 is as small as 0.1 to 10 parts by mass with respect to 100 parts by mass of the rubber component. However, sufficient lateral pressure resistance can be secured.

The compressed rubber layer 8 and the adhesive rubber layer 7 preferably contain chloroprene rubber. When the compression rubber layer 8 and the adhesive rubber layer 7 contain chloroprene rubber having a good balance of physical properties such as heat resistance, wear resistance, and weather resistance, the durability of the transmission V-belt 1 can be improved. Further, since the adhesive force between the reinforcing layer 6 and the compressed rubber layer 8 and the adhesive force between the reinforcing layer 6 and the adhesive rubber layer 7 are improved, and peeling between them can be suppressed, The life of the V belt 1 can be further extended. Furthermore, since chloroprene rubber is relatively inexpensive, it is excellent in economic efficiency.

The reinforcing layer 6 is composed of one or a plurality of laminated unidirectional fiber sheets 10. The unidirectional fiber sheet 10 has a structure in which reinforcing fiber filaments 11 are bonded to each other by a thermosetting resin. Therefore, since the adhesiveness between the reinforcing fiber filament 11 and the rubber composition is improved by the thermosetting resin, the power transmission V-belt 1 can have a longer life.

When the configuration of the unidirectional fiber sheet 10 is the same, the side pressure resistance can be improved as the number of the unidirectional fiber sheets 10 constituting the reinforcing layer 6 increases. Moreover, when the structure of the unidirectional fiber sheet 10 is the same, the fall of a flexibility can be suppressed, so that there are few number of the unidirectional fiber sheets 10 which comprise the reinforcement layer 6. FIG.

When the basis weight of the unidirectional fiber sheet 10 is less than 50 g / m ² , the number of unidirectional fiber sheets constituting the reinforcing layer 6 necessary to ensure sufficient lateral pressure resistance increases, which is useful for belt production. Such man-hours increase. The basis weight of the unidirectional fiber sheet 10 is preferably 50 g / m ² or more. Thereby, sufficient lateral pressure resistance can be secured by the reinforcing layer 6 constituted by one or a small number of unidirectional fiber sheets 10.
When the basis weight of the unidirectional fiber sheet 10 exceeds 400 g / m ² , the reinforcing layer 6 is thick even if the reinforcing layer 6 is composed of one unidirectional fiber sheet 10. In some cases, the flexibility may decrease. The basis weight of the unidirectional fiber sheet 10 is preferably 400 g / m ² or less, more preferably 200 g / m ² or less (particularly 100 g / m ² or less). Thereby, the fall of a flexibility can be suppressed.

The method for manufacturing the transmission V-belt 1 includes a rubber layer 4 having one reinforcing fiber 6 as a single reinforcing layer 6 or a single laminated fiber sheet 10 having a structure in which reinforcing fiber filaments 11 are joined together. A lamination step of laminating

unvulcanized rubber sheets

117A, 117B, and 119 that form other portions of the rubber layer 4 after being laminated on a part of the unvulcanized rubber sheet 118; And vulcanizing the

sheets

118, 117A, 117B, 119 to form the rubber layer 4.

According to this method, the conventional method of manufacturing a conventional transmission V-belt can be used as it is, and the manufacturing process can be prevented from becoming complicated. Furthermore, it becomes possible to embed the reinforcing layer 6 at an arbitrary position from the belt inner surface side to the outer surface side, and it is possible to reinforce a place where the side pressure resistance is particularly enhanced.

Prior to the lamination step, it is preferable to adhere the adhesive component to the unidirectional fiber sheet 10 by RFL treatment or rubber paste treatment.
According to this method, since the adhesive force between the reinforcing fiber filament 11 and the rubber composition is increased, peeling between the reinforcing layer 6 and the rubber layer 4 can be prevented, and the transmission V-belt 1 can have a longer life.
In addition, since the reinforcing fiber filaments 11 are more firmly bonded to each other by the adhesive component, it is possible to more reliably prevent the disorder of the orientation of the reinforcing fiber filaments 11.

The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. Hereinafter, modified examples of the present invention will be described. The above-mentioned embodiment and these modified examples can be implemented in combination as appropriate.

<Modification 1>
The unidirectional fiber sheet 10 of the said embodiment is the structure by which reinforcement fiber filaments 11 were couple | bonded with the thermosetting resin. However, the unidirectional fiber sheet of the present invention may have a configuration in which reinforcing fiber filaments are bonded to each other by means other than a thermosetting resin.

For example, in the unidirectional fiber sheet, the reinforcing fiber filaments along the belt width direction are bonded to each other by an auxiliary thread that intersects the belt width direction and has a weight per unit area of 30% or less of the reinforcing fiber filament. May be. Specifically, for example, a fiber bundle 213 composed of a plurality of reinforcing fiber filaments and an auxiliary yarn 214 intersect each other in a plain weave like a unidirectional fiber sheet 210 shown in FIG. Good. Further, for example, as shown in FIG. 6B, a unidirectional fiber sheet 310 woven with a fiber bundle 313 composed of a plurality of reinforcing fiber filaments and auxiliary yarns 314 may be used.
The auxiliary yarns may be along the belt circumferential direction as in the

auxiliary yarns

214 and 314 shown in FIGS. 6A and 6B, and are inclined with respect to the belt circumferential direction and the belt width direction. Also good. The fineness of the auxiliary yarn is preferably smaller than the fineness of the fiber bundle of the reinforcing fiber filament. The type of fiber of the auxiliary yarn is not particularly limited, and may be the same as or different from the type of fiber of the reinforcing fiber filament. The auxiliary yarn may be a twisted yarn or a non-twisted yarn.
The weight per unit area of the auxiliary yarn included in the reinforcing layer is 30% or less of the weight per unit area of the reinforcing fiber filament included in the reinforcing layer. Therefore, it is possible to suppress a decrease in flexibility as in the above embodiment. From the viewpoint of suppressing a decrease in flexibility, the weight per unit area of the auxiliary yarn is preferably 20% or less of the weight per unit area of the reinforcing fiber filament, and more preferably 10% or less. The lower limit of the weight per unit area of the auxiliary yarn is not particularly limited, but may be about 0.1% of the weight per unit area of the reinforcing fiber filament.
When the reinforcing fiber filaments are bonded with resin as in the above embodiment, the flexibility of the belt may be lowered depending on the type and thickness of the resin. When reinforcing fiber filaments are joined with auxiliary yarns, it is easy to suppress a decrease in flexibility. Also, compared to the case where reinforcing fiber filaments are bonded with resin, the unidirectional fiber sheet is torn when a strong force is applied to the unidirectional fiber sheet in the belt circumferential direction during adhesion processing or molding. Hateful.

When the reinforcing fiber filaments are bonded together by means other than thermosetting resin, the thickness of the reinforcing layer, the basis weight of the unidirectional fiber sheet, and the properties of the reinforcing fiber filament (thickness, tensile elastic modulus, thermal conductivity) The preferred range and specific examples of the material of the reinforcing fiber filament are the same as in the above embodiment. The basis weight of the unidirectional fiber sheet in which the reinforcing fiber filaments are bonded by means other than the thermosetting resin is a basis weight including means (for example, auxiliary yarn) for bonding the reinforcing fiber filaments. As a specific example of the unidirectional fiber sheet in which the reinforcing fiber filaments are bonded to each other by means other than the thermosetting resin, there is, for example, “Fibra sheet” manufactured by Fivex Corporation. The unidirectional fiber sheet in which the reinforcing fiber filaments are bonded together by means other than the thermosetting resin may form a reinforcing layer with only one sheet, or a plurality of laminated layers constitute the reinforcing layer. Also good.

When the reinforcing fiber filaments are bonded to each other by the auxiliary yarn, the unidirectional fiber sheet (reinforcing layer) is preferably subjected to an adhesive treatment such as RFL treatment, rubber paste treatment, resin impregnation treatment, or the like. The resin impregnation treatment is a treatment in which the unidirectional fiber sheet is impregnated with a resin solution such as an isocyanate solution or an epoxy solution. After the resin impregnation treatment, an RFL treatment or a rubber paste treatment may be performed. By performing the adhesion treatment, the adhesion with the rubber layer can be enhanced.

<Modification 2>
In the above embodiment, two reinforcing layers 6 are provided, but the number of reinforcing layers provided on the transmission V-belt of the present invention may be one or three or more. When there is one reinforcing layer, it may be embedded on either the inner belt side or the outer belt side of the core. When there are a plurality of reinforcing layers, two or more reinforcing layers may be embedded on the inner peripheral side of the belt from the core wire. Moreover, when there are a plurality of reinforcing layers, two or more reinforcing layers may be embedded on the outer peripheral side of the belt from the core wire.

<Modification 3>
In the above embodiment, the reinforcing layer 6 is embedded between the compressed rubber layer 8 and the adhesive rubber layer 7. However, as shown in FIG. 7, for example, the reinforcing layer 406 may be embedded in the compressed rubber layer 408. . The reinforcing layer 406 is constituted by three laminated unidirectional fiber sheets 10. In the above embodiment, the reinforcing layer 6 is embedded between the stretch rubber layer 9 and the adhesive rubber layer 7. However, the reinforcement layer may be embedded in the stretch rubber layer. In terms of improving the lateral pressure resistance, the reinforcing layer is preferably embedded in the vicinity of the core wire, but the reinforcing layer may be embedded away from the core wire. For example, as shown in FIG. 7, a reinforcing layer 406 may be embedded in the center of the compressed rubber layer 408 in the belt thickness direction. Further, for example, a reinforcing layer may be embedded on the inner peripheral side of the belt from the substantially center of the compressed rubber layer in the belt thickness direction. By embedding the reinforcing layer in the compressed rubber layer or the stretched rubber layer, buckling deformation due to dishing is reduced, and it is possible to suppress heat generation of the belt and separation between constituent members. Therefore, the life of the transmission V-belt can be further extended. If the reinforcing layer is embedded in the center of the belt in the thickness direction of the compressed rubber layer or closer to the inner circumference of the belt than the center, the amount of rubber that is compressed during buckling deformation increases, and the elastic repulsion increases and buckling occurs. Deformation can be suppressed.

<Modification 4>
In the present invention, when the rubber layer is composed of an adhesive rubber layer, a compressed rubber layer, and an extended rubber layer, only a part of the core wire may be embedded in the adhesive rubber layer.
For example, the core wire 5 may be embedded between the adhesive rubber layer 507 and the stretch rubber layer 509 as in the transmission V-belt 501 shown in FIG. In FIG. 8B, the reinforcing layer 6 is embedded between the compressed rubber layer 8 and the adhesive rubber layer 507. The reinforcing layer 6 may be embedded anywhere except between the adhesive rubber layer 507 and the stretched rubber layer 509. FIG. 8A shows a state in which the constituent elements of the belt main body are wound around the forming drum M in the manufacturing process of the transmission V-belt 501. The core wire 5 is disposed between an unvulcanized rubber sheet 519 that forms the stretched rubber layer 509 and an unvulcanized rubber sheet 517 that forms the adhesive rubber layer 507.
Moreover, although illustration is abbreviate | omitted, a core wire may be embed | buried between an adhesive rubber layer and a compression rubber layer. In this case, the reinforcing layer may be embedded anywhere except between the adhesive rubber layer and the compressed rubber layer.

<Modification 5>
In the present invention, the rubber layer may not have an adhesive rubber layer. The rubber layer may be composed only of a compressed rubber layer and an extended rubber layer made of a rubber composition different from the compressed rubber layer. In this modified example, the core wire is not embedded in the adhesive rubber layer.
For example, like the transmission V belt 601 shown in FIG. 9B, the core wire 5 may be embedded between the compression rubber layer 608 and the stretch rubber layer 609. In FIG. 9B, two reinforcing layers 6 are embedded in the compressed rubber layer 608 and the stretched rubber layer 609, respectively. FIG. 9A shows a state in which the constituent elements of the belt main body are wound around the forming drum M in the manufacturing process of the transmission V-belt 601. One of the two reinforcing layers 6 is disposed between two

unvulcanized rubber sheets

618A and 618B that form the compressed rubber layer 608. The other reinforcing layer 6 is disposed between two

unvulcanized rubber sheets

619A and 619B forming the stretched rubber layer 609.
For example, the core wire 5 may be embedded in the compression rubber layer 708 like a transmission V-belt 701 shown in FIG. In FIG. 10B, two reinforcing layers 6 are embedded between the compressed rubber layer 708 and the compressed rubber layer 708 and the stretched rubber layer 9, respectively. The reinforcing layer may be embedded in the stretch rubber layer 9 or in the compressed rubber layer 708. FIG. 10A shows a state in which the constituent elements of the belt main body are wound around the forming drum M in the manufacturing process of the transmission V-belt 701. The compressed rubber layer 708 is formed by three

unvulcanized rubber sheets

718A, 718B, 718C.
Further, although not shown, the core wire may be embedded in the stretched rubber layer. In this case, the reinforcing layer may be embedded in the stretched rubber layer, may be embedded in the compressed rubber layer, or may be embedded between the compressed rubber layer and the stretched rubber layer.
When the adhesive rubber layer is not provided, the man-hour for manufacturing the belt can be reduced.

<Modification 6>
When the adhesive rubber layer is not provided and the reinforcing layer is embedded in the vicinity of the core wire, if the reinforcing layer is subjected to an adhesive treatment such as RFL treatment, resin impregnation treatment, rubber paste treatment, etc. It is not necessary to interpose a rubber sheet between the layer and the core wire. The transmission V belt shown in FIG. 11B is an example. As shown in FIGS. 11A and 11B, the belt body of the transmission V-belt 801 includes an unvulcanized rubber sheet 818 that forms the compressed rubber layer 8, the reinforcing layer 6, the core wire 5, and the stretched rubber. The unvulcanized rubber sheet 819 forming the layer 809 is wound around the molding drum M in order.

<Modification 7>
The transmission V-belt of the present invention may be a low-edge V-belt whose friction transmission surface is not covered with a cover cloth. The cover cloth may not be provided at all, and the cover cloth may be provided only on at least one of the outer peripheral surface and the inner peripheral surface.

<Modification 8>
The transmission V-belt of the present invention may be a cog belt having a plurality of cogs arranged in the belt circumferential direction on at least one of the belt inner circumferential surface and the belt outer circumferential surface. FIG. 12 shows an example. The belt main body 902 of the cog belt (transmission V-belt) 901 in FIG. 12 has a cog 902a only on the inner peripheral surface. In FIG. 12, the reinforcing layer 906 is embedded in the compressed rubber layer 908. When the reinforcing layer is embedded in the vicinity of the core wire in the cog belt, the reinforcing layer may be embedded along the core wire without following the unevenness of the cog. On the other hand, when the reinforcing layer is embedded in the cog belt at a position close to the cog, for example, as shown in FIG. 12, the reinforcing layer 906 may be arranged along the unevenness of the cog 902a. Cog molding is performed by fitting an unvulcanized belt sleeve or unvulcanized belt body to a molding matrix (mold or rubber mold) in which irregularities are formed, in the same manner as a general cog belt. be able to.

Tests for demonstrating the effects of the present invention were conducted on the V-belts for transmission of the examples and comparative examples of the present invention. Table 1 shows the configurations of the transmission V-belts of Examples 1 to 7 and Comparative Examples 1 to 4. The transmission V-belts of Examples 1 to 6 and Comparative Examples 1 to 4 were wrapped V-belts having a belt type B defined in JIS K6323 (2008), a nominal number of 60, and a circumference of 1524 mm. The transmission V-belt of Example 7 was a low-edge V-belt having a belt type defined by JISK6323 (2008), type B, nominal number 60, and circumference of 1524 mm. That is, the friction transmission surface of the transmission V-belt of Example 7 is not covered with the cover cloth.

Among the embedding positions of the reinforcing layer in Table 1, “upper core” means a state where the reinforcing layer is embedded between the adhesive rubber layer and the stretch rubber layer. “Below the core wire” means a state in which the reinforcing layer is embedded between the adhesive rubber layer and the compressed rubber layer. “In the compressed rubber” means a state in which the reinforcing layer is embedded in the compressed rubber layer.

Each reinforcing layer of Examples 1 to 3, 5 to 7 was composed of one unidirectional fiber sheet. As the unidirectional fiber sheets of Examples 1 to 3, 5 to 7, unidirectional carbon fiber sheets in which carbon fiber filaments oriented in one direction were bonded with a thermosetting resin were used. The basis weight of the unidirectional fiber sheet of Example 3 was twice (100 g / m ² ) the basis weight of the unidirectional fiber sheets of Examples 1, 2, and 5-7. The reinforcing layer of Example 4 was composed of two laminated unidirectional fiber sheets. The unidirectional fiber sheet of Example 4 was the same as the unidirectional fiber sheets of Examples 1, 2, 5-7. The thicknesses of the reinforcing layers in Examples 1, 2, and 5 to 7 were 0.1 mm, and the thicknesses of the reinforcing layers in Examples 3 and 4 were 0.2 mm. The unidirectional fiber sheets of Examples 1 to 7 were subjected to RFL treatment.

In the transmission V-belts of Comparative Examples 1 and 4, no reinforcing layer was embedded. In the transmission V belts of Comparative Examples 2 and 3, a single cord was used as a reinforcing layer. The braided cord of Comparative Example 2 has a configuration in which twisted cords (1670 dtex / 1 × 2) of aramid fibers oriented in one direction are connected by cotton thin yarn (count 20S / 1). The density of the aramid fiber twist cord was 50/5 cm, and the density of the fine yarn was 4/5 cm. The thickness of the reinforcing layer of Comparative Example 2 (the thickness of the tinted cord) was 0.7 mm. The interdigital cord of Comparative Example 3 has a configuration in which twisted cords (1100 dtex / 1 × 2) of PET fibers oriented in one direction are connected by cotton thin yarn (count 20S / 1). In Comparative Examples 2 and 3, the density of the twisted cord was 50 / 5cm, and the density of the fine yarn was 4 / 5cm. The thickness of the reinforcing layer of Comparative Example 3 (the thickness of the tinted cord) was 0.6 mm. In both Comparative Examples 2 and 3, the cord was subjected to RFL treatment. In both Comparative Examples 2 and 3, the interlaced cords were arranged so that the twisted cords were oriented in the belt width direction.

As shown in Table 1, the configurations of the stretched rubber layer and the compressed rubber layer in Examples 1 to 7 and Comparative Examples 1 to 3 were all the same. The stretched rubber layer and the compressed rubber layer of Comparative Example 4 were configured to include more short fibers than the stretched rubber layer and the compressed rubber layer of Example 1 and the like. The structures of the adhesive rubber layers and the core wires in Examples 1 to 7 and Comparative Examples 1 to 4 were all the same. For the core wire, an aramid cord having a total fineness of 4400 dtex, in which a filament of an aramid fiber having a fineness of 1100 dtex was twisted (S twist) and four of them were aligned and twisted (Z twist), was used. The cover fabrics of Examples 1 to 6 and Comparative Examples 1 to 4 were woven fabrics plain woven with a mixed yarn of cotton and polyethylene terephthalate (PET) fibers. The compositions of rubber composition A and rubber composition B in Table 1 are as shown in Table 2.

Details of each component in Table 2 are as follows.
・ Chloroprene rubber: “PM-40” manufactured by Denka Co., Ltd.
・ Polyamide short fiber: “66 nylon” manufactured by Asahi Kasei Corporation
・ Carbon black: “Seast 3” manufactured by Tokai Carbon Co., Ltd.
・ Silica: “Nippil VN3” manufactured by Tosoh Silica Corporation
・ Naphthenic oil: “NS-900” manufactured by Idemitsu Kosan Co., Ltd.
Resorcin / formaldehyde condensate: less than 20% resorcinol, less than 0.1% formalin Anti-aging agent: “Nonflex OD3” manufactured by Seiko Chemical Co., Ltd.
・ Vulcanization accelerator DM: Di-2-benzothiazolyl disulfide ・ Vulcanization accelerator TMTD: Tetramethylthiuram disulfide

[Side pressure resistance test]
Using the transmission V-belts of Examples 1 to 7 and Comparative Examples 1 to 4, a side pressure resistance test was performed. First, the transmission V-belt was cut to prepare a side pressure resistance evaluation sample S having a belt circumferential length of 70 mm. Then, as shown in FIG. 13, the sample S is sandwiched vertically between the

jigs

51 and 52 so that the friction transmission surface of the side pressure resistance evaluation sample S is in contact with the two

metal jigs

51 and 52. It is. The position of the upper jig 51 in a state where the sample S is sandwiched without being pressed by the two jigs is defined as an initial position. Using an autograph (“AGS-J10kN” manufactured by Shimadzu Corporation), the upper jig 51 is lowered at a speed of 5 mm / min, and the moving distance from the initial position of the upper jig 51 is 1.4 mm. The compressive force at the time of was measured. It can be determined that the higher the measured compression force, the higher the lateral pressure resistance. Table 3 shows the measurement results.

[Flexibility test]
Using the transmission V belts of Examples 1 to 7 and Comparative Examples 1 to 4, a flexibility test was performed. As shown in FIG. 14, the transmission V-belt B was disposed between two metal plates 61 and 62 arranged vertically with an interval of 180 mm. The position of the upper metal plate 61 at this time is set as the initial position. When the upper metal plate 61 is lowered at a speed of 50 mm / min using an autograph (“AGS-J10kN” manufactured by Shimadzu Corporation), and the moving distance from the initial position of the upper metal plate 61 is 100 mm The compressive force of was measured. It can be determined that the lower the measured compressive force, the better the flexibility. Table 3 shows the measurement results.

[Durability test]
Using the transmission V belts of Examples 1 to 7 and Comparative Examples 1 to 4, a durability running test was performed to evaluate the belt temperature and the belt life. The endurance running test was conducted using a two-axis running test machine comprising a driving pulley having a diameter of 129 mm and a driven pulley having a diameter of 129 mm. A transmission V belt is hung on these two pulleys, the axial load of the driven pulley is constant at 120 kgf, the rotational speed of the driving pulley is 1800 rpm, a load of 8 kW is applied to the driven pulley, and the atmosphere is 25 ° C. The belt was run until it was damaged. The belt temperature during running was measured every 24 hours. Table 3 shows the maximum temperature, the running life time, and the failure mode among the measured belt temperatures.

As shown in Table 3, Examples 1 to 7 in which a unidirectional fiber sheet was embedded as a reinforcing layer improved the lateral pressure resistance as compared with Comparative Example 1 in which no reinforcing layer was provided, and was comparable to Comparative Example 1. Good flexibility was maintained. Since the lateral pressure resistance could be improved, sufficient lateral pressure resistance could be secured even when the amount of short fibers in the rubber composition was as small as 5 parts by mass with respect to 100 parts by mass of the rubber component. Comparing Example 1 and Example 2, Example 1 in which the reinforcing layers are provided on both sides of the core wire greatly reduces the flexibility compared to Example 2 in which the reinforcing layer is provided only on one side of the core wire. The side pressure resistance was improved. Of Examples 1, 3, and 4 in which unidirectional carbon fiber sheets are embedded on both sides of the core wire, Example 3 using a unidirectional carbon fiber sheet having a basis weight of 100 g / m ² and a basis weight of 50 g / example were laminating two unidirectional carbon fiber sheets in m ² 4 has a high lateral pressure resistance than example 1 was used without laminating the unidirectional carbon fiber sheet having a basis weight 50 g / m ^2, The running life has been improved. In Examples 5 and 6 in which the reinforcing layer was embedded in the compressed rubber layer, lateral pressure resistance and running life were similar to those in Example 1 in which the reinforcing layer was embedded on both sides of the core wire. Further, from the comparison between Example 1 and Example 7, it was confirmed that the low-edge V belt can obtain the same effect as the wrapped V belt. In Comparative Examples 2 and 3 in which the brazing cord was embedded as a reinforcing layer, the side pressure resistance was improved as compared with Comparative Example 1, but the flexibility was lower than that of Comparative Example 1 and Examples 1 to 5. The decrease in the flexibility of Comparative Examples 2 and 3 is considered to be caused by the fact that the thickness of the reinforcing layer exceeds 0.5 mm and the fine yarns are arranged so as to intersect the belt width direction. In Comparative Example 4 containing a large amount of short fibers, although the lateral pressure resistance is improved as compared with Comparative Example 1, the short fibers are low in orientation compared to the unidirectional carbon fiber sheet, and the flexibility is low. The running life did not improve much.

When the belt temperature was compared, in Examples 1 to 7 and Comparative Example 1, the belt temperature was kept low, but in Comparative Examples 2 to 4, the belt temperature was high. In Comparative Examples 2 and 3, the reinforcing layer is composed of a twisted cord, and thus it is considered that the twisted cord generates a lot of frictional heat at the time of bending, leading to an increase in the belt temperature. Furthermore, in Comparative Examples 2 and 3, it was considered that the increase in belt temperature was due to the fact that the thickness of the reinforcing layer decreased the flexibility so that heat generation due to the bending was likely to occur. Further, in Comparative Example 4, since a large amount of short fibers were blended, the flexibility was lowered and heat generation due to the bending was likely to occur, which is considered to have led to an increase in the belt temperature. On the other hand, in Examples 1 to 7, it is considered that heat generation was suppressed by embedding a thin reinforcing layer composed of untwisted reinforcing fiber filaments. Further, in Examples 1 to 7, it is considered that the use of carbon fibers having high thermal conductivity also had an effect of radiating the generated heat.

Comparing the running life, Comparative Example 1 was the shortest, and Examples 1 to 7 were longer than Comparative Examples 1 to 4. In Comparative Example 1 in which no reinforcing layer was provided, delamination occurred between the core wire and the rubber composition. This is considered to be because the belt was deformed by the side pressure from the pulley because the side pressure resistance is low by not providing the reinforcing layer.
In Comparative Examples 2 and 3 in which a reinforcing layer composed of twisted cords was embedded, and in Comparative Example 4 in which a large amount of short fibers were blended, rubber cracks occurred. In Comparative Examples 2 to 4, since the belt temperature increased as described above, it is considered that the deterioration of the rubber due to heat was promoted, leading to a rubber crack.
In Examples 1 and 3 to 7 in which the reinforcing layers were provided in two or more places, the running life was longer than that in Example 2 in which the reinforcing layers were provided only in one place. This is considered to be because the side pressure resistance of Examples 1 and 3 to 7 was higher than that of Example 2.
In Examples 1 to 7, damage due to delamination did not occur. In Examples 1 to 7, it is considered that the adhesion between the rubber composition and the reinforcing layer was good because the adhesive component was adhered to the reinforcing layer by the RFL treatment.

Although the invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the invention.
This application is based on Japanese Patent Application No. 2017-011806 filed on Jan. 26, 2017 and Japanese Patent Application No. 2018-004453 filed on Jan. 15, 2018, the contents of which are incorporated herein by reference.

1,501,601,701,801,901 Transmission V-

belt

1a, 1b Friction transmission surface 4 Rubber layer 5 Core wire 6,406,906 Reinforcement layer 7,507 Adhesive rubber layer 8,408,608,708,908

Compression Rubber layer

9, 509, 609, 809

Stretched rubber layer

10, 210, 310 Unidirectional fiber sheet 11 Reinforcing fiber filament 12

Thermoplastic resin

214, 314 Auxiliary yarn

Claims

A transmission V-belt having a V-shaped cross section perpendicular to the belt circumferential direction and having friction transmission surfaces on both sides in the belt width direction,
A rubber layer comprising a rubber composition;
A core wire embedded along the circumferential direction of the belt in the rubber layer;
And at least one reinforcing layer embedded in the rubber layer,
The reinforcing layer includes a plurality of reinforcing fiber filaments having the same length as the belt width, and does not include a fiber that intersects the belt width direction or, when included, per unit area of the fibers that intersect the belt width direction. The weight is 30% or less of the reinforcing fiber filament,
The reinforcing layer has a structure in which the reinforcing fiber filaments are spread and bonded in a sheet shape while being oriented in the belt width direction in an untwisted state,
A transmission V-belt in which the thickness of the reinforcing layer is 0.05 mm to 0.5 mm.
In the transmission V belt according to claim 1,
The tensile elastic modulus of the reinforcing fiber filament is 200 to 600 GPa.
The transmission V-belt according to claim 1 or 2,
The reinforcing fiber filament has a thermal conductivity of 5.0 W / (m · K) or more.
The transmission V-belt according to any one of claims 1 to 3,
The reinforcing fiber filament is a carbon fiber.
The transmission V-belt according to any one of claims 1 to 4,
One reinforcing layer is embedded on each side of the core wire in the rubber layer.
The transmission V-belt according to any one of claims 1 to 5,
The rubber layer is
An adhesive rubber layer in which at least a part of the core wire is embedded;
Composed of a rubber composition different from the adhesive rubber layer, and a compressed rubber layer provided on the belt inner peripheral side of the adhesive rubber layer;
It is composed of a rubber composition different from the adhesive rubber layer, and has an extended rubber layer provided on the belt outer peripheral side of the adhesive rubber layer,
The reinforcing layer is embedded between at least one of the adhesive rubber layer and the compressed rubber layer and between the adhesive rubber layer and the stretched rubber layer.
The transmission V-belt according to any one of claims 1 to 5,
The rubber layer is
An adhesive rubber layer in which at least a part of the core wire is embedded;
Composed of a rubber composition different from the adhesive rubber layer, and a compressed rubber layer provided on the belt inner peripheral side of the adhesive rubber layer;
It is composed of a rubber composition different from the adhesive rubber layer, and has an extended rubber layer provided on the belt outer peripheral side of the adhesive rubber layer,
The reinforcing layer is embedded in at least one of the compressed rubber layer and the stretched rubber layer.
The transmission V-belt according to any one of claims 1 to 5,
The rubber layer is
A compressed rubber layer;
It is composed of a rubber composition different from the compressed rubber layer, and has an extended rubber layer provided on the belt outer peripheral side of the compressed rubber layer,
The core wire is embedded between the compressed rubber layer and the stretched rubber layer, the compressed rubber layer, or the stretched rubber layer,
The reinforcing layer is embedded in at least one of the compressed rubber layer, the stretched rubber layer, and the compressed rubber layer and the stretched rubber layer.
The transmission V-belt according to any one of claims 6 to 8,
The cord is not embedded in the compressed rubber layer, the compressed rubber layer contains short fibers, and the amount of the short fibers in the compressed rubber layer is 0.1 parts by mass with respect to 100 parts by mass of the rubber component. ~ 10 parts by mass.
The transmission V-belt according to any one of claims 6 to 9,
The reinforcing layer is embedded in or in contact with the compressed rubber layer;
The compressed rubber layer comprises chloroprene rubber;
When the reinforcing layer is in contact with the adhesive rubber layer, the adhesive rubber layer contains chloroprene rubber.
The transmission V-belt according to any one of claims 1 to 10,
The reinforcing layer is composed of one sheet or a plurality of laminated unidirectional fiber sheets,
The unidirectional fiber sheet has a structure in which the reinforcing fiber filaments are bonded together by a thermosetting resin.
The transmission V-belt according to any one of claims 1 to 10,
The reinforcing layer is composed of one sheet or a plurality of laminated unidirectional fiber sheets,
The unidirectional fiber sheet has a structure in which the reinforcing fiber filaments are bonded to each other by an auxiliary yarn that intersects the belt width direction and has a weight per unit area of 30% or less of the reinforcing fiber filaments.
The transmission V-belt according to claim 11 or 12,
The basis weight of the unidirectional fiber sheet including the thermosetting resin or the auxiliary yarn is 50 to 400 g / m 2 .
A method for manufacturing the transmission V-belt according to claim 1,
A first unvulcanized rubber forming a part of the rubber layer by using one or a plurality of laminated unidirectional fiber sheets having a structure in which the reinforcing fiber filaments are bonded as one reinforcing layer Laminating a layer, and then laminating a second unvulcanized rubber layer that forms another part of the rubber layer from above,
And a vulcanizing step of vulcanizing the first unvulcanized rubber layer and the second unvulcanized rubber layer to form the rubber layer.
In the manufacturing method of the transmission V belt of Claim 14,
Prior to the laminating step, an adhesive component is attached to the unidirectional fiber sheet by at least one of RFL treatment, rubber paste treatment, and resin impregnation treatment.