JP2022085864A - Joined v-belt - Google Patents

Abstract

To provide a joined V-belt which can effectively suppress a circular cut even in a high-load environment, its manufacturing method and a round-cut suppression method.SOLUTION: In a joined V-belt 10 which includes a plurality of V-belt parts V aligned in a belt width direction, and a cable tie T for connecting external peripheral faces of the plurality of V-belt parts V, and in which each of the V-belt parts V includes a core body layer 6 including a core body 5, an elongation layer 4 laminated on a belt external peripheral side of the core body layer 6, and a compression rubber layer 7 laminated on a belt internal peripheral side of the core body layer 6, a connection reinforcing layer 1 including a fiber structure 2 is used in the cable tie T, the fiber structure 2 includes a plurality of first stringlike bodies 2a at least extending in the belt width direction, and the first stringlike bodies 2a are arranged with at least intervals in a belt length direction. The adjacent first stringlike bodies may be arranged with a clearance of 0.5 to 7.5 mm in the belt length direction.SELECTED DRAWING: Figure 1

Description

The present invention is a coupled V-belt (multi-V-belt, banded belt) in which a plurality of V-belts are wound around a pulley or the like and used simultaneously in a high-load, long-span (long distance between shafts) layout such as a large-scale agricultural machine. ), Its manufacturing method, and a method for suppressing vertical tearing.

The V-belt that transmits power by friction transmission includes a low edge (Raw-EDGE) type (low edge V-belt) that is a rubber layer with an exposed friction transmission surface (V-shaped side surface), and the friction transmission surface is covered with a cover cloth. There is a broken type (wrapped V-belt), and it is used properly according to the application because of the difference in the surface texture (friction coefficient between the rubber layer and the cover cloth) of the friction transmission surface. These V-belts are used in a wide range of fields such as large automobiles such as trucks and buses and industrial machines, and are used at high loads due to an increase in transmission capacity and an increase in the size of equipment. Thin V-ribbed belts are widely used in applications that do not require such a large transmission capacity, such as for driving auxiliary equipment in ordinary automobiles, but in high-load applications where the transmission capacity is insufficient for V-ribbed belts, large Vs are used. A belt is used. Belts used in high-load environments, such as large V-belts, are required to have high rigidity (side pressure resistance) in the width direction of the belt in order to prevent buckling deformation (dishing), so that they can withstand high loads. Material selection and product design different from V-ribbed belts are required.

These V-belts are used by only one in the case of applications where power can be transmitted by themselves, but in an environment where the power to be transmitted is larger, for example, in a large-scale agricultural machine used in Europe and the United States. , It becomes necessary to use a plurality of V-belts at the same time.

However, when a plurality of V-belts are wound around a pulley of a rotating device in a state of being arranged in parallel, a tension difference may occur between the belts and stable power transmission may be impaired. Further, the adjacent belts may come into contact with each other, and the contact may cause the inner peripheral side and the outer peripheral side of the belt to be inverted so as to be turned over and overturned. In addition, in the layout of large-scale agricultural machines used in Europe and the United States, the distance between the pulleys around which the V-belt is wound is very long, so the V-belt tends to swing significantly during running, and more than one. If the belt length is not uniform, it may be vibrated.

Therefore, in such a usage environment, a coupled V-belt configured by connecting a plurality of annular V-belt portions having the same or corresponding configurations as the above-mentioned V-belt is used. The coupled V-belt is configured as a V-belt in which a plurality of the V-belt portions are arranged in parallel and the outer peripheral side of each V-belt portion is connected and connected by a connecting member (tie band) such as a reinforcing cloth.

As such a bonded V-belt, for example, Japanese Patent Application Laid-Open No. 47-34432 (Patent Document 1) provides a bonded V-belt provided with a connecting band provided with a woven fabric layer having threads crossed in an oblique direction with respect to the longitudinal direction of the belt. Is disclosed. It is also described that the load transmission capacity is high because it acts as the tension of the thread when the load is transmitted between the belt bodies, and that the crossover angle of the thread may be in the range of 90 or 95 to 155 °. There is.

Japanese Patent Application Laid-Open No. 55-45082 (Patent Document 2) discloses a configuration including a connecting member in which at least two layers of rubber-attached bamboo blind records are cross-laminated. Further, the crossover angle may be 95 to 150 °, and it is described that the elasticity in the vertical direction, the elasticity in the horizontal direction, and the rigidity can be improved.

Japanese Patent Application Laid-Open No. 55-135244 (Patent Document 3) discloses a bonded V-belt connected and integrated by a stretchable canvas with rubber. Further, the warp and weft of the elastic canvas may be a woolly-processed crimped nylon yarn, and the crimped nylon yarn may be arranged at an angle of 0 to 40 ° with respect to the longitudinal direction of the belt. It is stated that.

Tokukousho 47-34432 Akira 55-45082 JP-A-55-135244

In the bonded V-belt, it is an issue to improve the durability of the bonded member. A tensile force in the belt width direction and a shear force in the belt length direction act on the coupling member of the coupling V-belt. In addition, foreign matter such as pebbles may get caught between the belt and the pulley, causing damage to the coupling member. As a result, a crack occurs in the connecting member, and the crack propagates in the belt length direction, so that the connection of each V-belt portion is lost, and a phenomenon called ring splitting (vertical tearing) in which the crack is divided into individual V-belts occurs. May occur.

However, the configuration described in the above patent document is not sufficiently effective in suppressing the looping of the coupled V-belt in recent years in which the transmission capacity continues to increase, and further improvement has been sought.

Therefore, an object of the present invention is to provide a coupled V-belt capable of effectively suppressing ring breakage even in a high load environment, a method for manufacturing the same, and a method for suppressing ring breakage.

As a result of diligent studies to achieve the above object, the present inventor forms a bonded V-belt by a tie band containing a specific fiber structure and arranging the fiber structure in a specific direction with respect to the belt. Then, they found that the ring breakage could be effectively suppressed even in a high load environment, and completed the present invention.

That is, the coupled V-belt of the present invention includes a plurality of V-belt portions (base belts) arranged in the belt width direction and a tie band for connecting the outer peripheral surfaces of the plurality of V-belt portions; each V-belt. A bonded V-belt including a core body layer including a core body, an extension layer laminated on the outer peripheral side of the belt of the core body layer, and a compressed rubber layer laminated on the inner peripheral side of the belt of the core body layer. And
The tie band has a connecting reinforcing layer containing a fiber structure (fiber aggregate); the fiber structure includes a plurality of first filaments extending at least in the width direction of the belt; the first filaments. However, they are arranged at least at intervals in the length direction of the belt. The first filaments adjacent to each other may be arranged with a gap of about 0.5 to 7.5 mm in the belt length direction.

The density of the first thread-like body may be about 5 to 50 lines / 50 mm (for example, 10 to 39 lines / 50 mm), and the fineness of the first thread-like body may be about 100 to 1000 dtex. good. The cover factor of the first filamentous body may be about 150 to 1200 (lines / 50 mm) × (dtex) ^1/2 . Further, the connecting reinforcing layer may further contain a rubber component, and the rubber component may be interposed between the first thread-like bodies adjacent to each other in the belt length direction. The first thread-like body may be a non-twisted yarn having a twist number of less than 1 time / 100 mm (0 times / 100 mm or more and less than 1 time / 100 mm) or a sweet twisted yarn having a twist number of 1 to 29 times / 100 mm. good. The first filament may contain synthetic fibers and / or inorganic fibers, wherein the synthetic fibers are at least one selected from polypropylene-based fibers, polyvinyl alcohol-based fibers, polyester-based fibers and polyamide-based fibers. It may contain synthetic fibers. The fiber structure may be a net that extends in a direction intersecting the belt width direction and includes at least a plurality of second filaments connected to the first filament. The tie band may be laminated on the outer peripheral side of the connecting reinforcing layer and may further have a protective layer containing a cloth.

The present invention is a method for manufacturing the bonded V-belt by connecting the outer peripheral surfaces of a plurality of V-belts arranged in the belt width direction to a tie band having the connecting reinforcing layer, and a plurality of Vs in the tie band. It includes a method of connecting the belt portions to suppress the ring breakage of the obtained coupled V-belt.

Since the bonded V-belt of the present invention contains a specific fiber structure and is formed by a tie band in which the fiber structure is arranged in a specific direction with respect to the belt, a high load environment, for example, a large transmission capacity is formed. Even if it is used for applications that require, it is possible to effectively suppress ring breakage.

FIG. 1 is a schematic cross-sectional perspective view showing a partial notch showing an example of the coupled V-belt of the present invention. FIG. 2 is a schematic cross-sectional view of an example of a V-belt portion constituting the coupled V-belt of the present invention. FIG. 3 is a schematic cross-sectional view for explaining a process of connecting a plurality of uncrosslinked V-belt portions with a tie band. FIG. 4 is a schematic diagram for explaining a method of measuring the friction coefficient of the V-belt portion of the coupled V-belt obtained in the examples. FIG. 5 is a schematic cross-sectional view for explaining a running test of the coupled V-belts obtained in Examples and Comparative Examples.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings, if necessary. In the following description, the same reference numerals may be given to elements (or members) having the same or common functions.

As an example of the coupled V-belt of the present invention, FIG. 1 shows a schematic cross-sectional perspective view of a partially cutout of the wound coupled V-belt. As shown in FIG. 1, the coupled V-belt 10 includes three V-belt portions V arranged in parallel in the belt width direction (B direction in FIG. 1) at intervals. Each outer peripheral surface of the V-belt portion V is a plurality of first thread-like bodies (thread bodies) extending in the belt width direction at intervals in the belt length direction (circumferential length direction, A direction in FIG. 1). The fiber structure 2 formed of 2a and a plurality of second thread-like bodies (thread bodies) 2b extending in the belt length direction at intervals in the belt width direction is contained in the rubber component (crosslinked rubber composition). It is connected by a tie band (bonding member) T having an embedded connecting reinforcing layer 1 and a protective layer 3 laminated on the connecting reinforcing layer 1 and formed of a cloth.

As with the conventional wrapped V-belt, each V-belt portion V has an stretch layer (stretch rubber layer) 4 and a core 5 [in this example, cores arranged at predetermined intervals in the belt width direction] from the outer peripheral side of the belt. A core layer (adhesive rubber layer) 6 in which a wire (twisted cord) is embedded in a crosslinked rubber composition, an endless belt body in which a compressed rubber layer 7 is sequentially laminated, and a belt circumference around the belt body. It is formed of an outer cover 8 (woven fabric, knitted fabric, non-woven fabric, etc.) covering the entire length in the direction.

In this example, the fiber structure 2 in the connecting reinforcing layer 1 has a net (net or net-like structure) having a structure in which warps (second filaments 2b) are alternately arranged above and below the wefts (first filaments 2a). (Structure), and the intersections (contact points or intersections) between the warp (second thread-like body 2b) and the weft (first thread-like body 2a) are bonded (bonded or bonded) with a resin. Further, in this example, the wefts (first filamentous body 2a) adjacent to each other are arranged with a gap of about 0.5 to 7.5 mm in the belt length direction. Further, the warp (second filament 2b) and warp (first filament 2a) in this example are both polyethylene terephthalate (PET) fibers (non-twisted yarn, mulch) having a fineness (total fineness) of 100 to 1000 dtex. It is a filament yarn), and the density (thread density) of each yarn is adjusted to 10 to 39 yarns / 50 mm.

In the conventional combined V-belt, as a tie band (bonding member) in order to achieve both improvement in flexibility in the belt length direction and elasticity in the belt width direction (improvement in ease of fitting to the pulley). Normally, a canvas or Suda record in which threads (thread-like bodies) are arranged diagonally (bias) with respect to the width of the belt is used. From the viewpoint of the mechanical characteristics of the band, the yarns are generally arranged at a high density (for example, a yarn density of about 70 to 80 threads / 50 mm) with almost no gaps.

On the other hand, in the coupled V-belt 10 of the present invention as described above, the wefts (first filamentous body 2a) extending in the belt width direction are arranged at a low density as the tie band T for connecting the back surfaces of the V-belt portions V. Surprisingly, it is possible to effectively suppress ring breakage (vertical tearing) despite the use of the fiber structure (net or net-like structure) 2. The reason why the ring breakage can be suppressed in this way is not clear, but since the warp and weft (first thread-like body 2a) is arranged so as to extend parallel to the belt width direction, resistance to the tensile force acting in the belt width direction It is considered that not only the force is improved and the cutting of the yarn is suppressed, but also the configuration in which the weft (first filamentous body 2a) is arranged at a low density at intervals has a great influence. More specifically, it was thought that a higher yarn density, such as a tie band in a conventional bonded V-belt, can improve the mechanical properties of the tie band and is less likely to cause ring breakage. When this occurs, stress is concentrated on the thread adjacent to the cut thread, and defects (or cracks) are likely to propagate (or grow) continuously, so by arranging the threads at high density instead. It was found that there was a tendency for the ring to break. That is, in the case where the threads extending in the width direction are arranged with a predetermined gap (or when the density of the threads is low) as in the present invention, even if the warp and weft (first thread-like body 2a) is cut, Since the distance between the cut weft and the adjacent weft is large, it becomes difficult for stress to concentrate on the adjacent weft, the propagation of cracks is suppressed, and the loop breakage is effective even though the yarn density is low. It is presumed that it can be suppressed. Further, in this example, since the rubber component (crosslinked rubber composition) is present between the adjacent weft threads (first filamentous body 2a), the stress is dispersed in the rubber component, and the defect is more difficult to propagate. At the same time, it is considered that the peeling of the fiber structure (net or net-like structure) 2 can be effectively suppressed.

The fiber structure (net or net-like structure) in the connecting reinforcing layer 1 is formed by laminating the protective layer 3 formed of a cloth on the connecting reinforcing layer 1 to form a tie band (bonding member) T. It is possible to effectively prevent 2 from being damaged by foreign matter from the back surface of the belt.

[Tie band (bonding member)]
The tie band in the bonded V-belt of the present invention may have at least a connecting reinforcing layer containing a specific fiber structure, and if necessary, includes a protective layer laminated on the outer peripheral side of the connecting reinforcing layer. May be.

[Connecting reinforcement layer]
(Fiber structure)
The fibrous structure in the connecting reinforcing layer contains a plurality of first filaments (threads) extending at least in the width direction of the belt, and the first filaments are at least spaced in the length direction of the belt. It is arranged.

In the present application, the first filamentous body (thread body) may extend substantially parallel to the belt width direction, and the angle formed by the extending direction of the first filamentous body (thread body) and the belt width direction. However, it means that it is, for example, about 10 ° or less (for example, 0 to 5 °), preferably 3 ° or less (for example, 0 to 1 °, particularly about 0 °).

Further, in the present application, the first filamentous body (thread body) extending at least in the belt width direction is not necessarily in the belt width direction as long as it can exhibit a resistance force against a tensile force acting in the belt width direction and suppress ring breakage. It does not have to extend in a straight line, and at the intersection (intersection or intersection) of the warp and the weft, for example, when the fiber structure is a woven fabric formed of the warp and the weft. It may have a curved portion that is partially bent or curved (for example, curved in a wavy shape in the belt thickness direction). The first filament is preferably formed by extending linearly over the entire belt width (or tie band width) by 50% or more, preferably 90% or more, and more preferably substantially the entire width. When the ratio of the straight portion is in such a range, the rigidity in the belt width direction is less likely to decrease, and it seems that it is easy to suppress the cutting of the yarn due to wear or the like at the intersection.

The thread density of the first thread-like body (the number of threads per 50 mm in the belt length direction) may be, for example, about 5 to 50 threads / 50 mm (for example, 8 to 45 threads / 50 mm), but as a conventional tie band. It can be selected from a range of low density, for example, 10 to 39 lines / 50 mm (for example, 12 to 35 lines / 50 mm, preferably 20 to 32 lines / 50 mm), preferably 15 to 30 lines / 50 mm, as compared with the sail cloth or Suda record. It may be about 50 mm (for example, 18 to 27 lines / 50 mm), more preferably about 20 to 25 lines / 50 mm. The range may be the range of the average value of the yarn densities. When the lower limit of the density of the first filamentous body is in such a range, the effect of increasing the rigidity (resistance to tensile force) in the belt width direction can be sufficiently obtained, and it becomes easy to suppress the ring breakage, and the first. When the upper limit of the density of the thread-like body is in such a range, even if the first thread-like body is cut, it becomes difficult for the defect (crack or cut) to propagate continuously in the belt length direction. There is a tendency to suppress ring breakage, and in particular, when the connecting reinforcing layer contains a rubber component (crosslinked rubber composition), the rubber component easily enters between the adjacent first filaments, and the vicinity of the defective portion. It seems that the stress acting on the rubber component is dispersed in the rubber component, the defect is more difficult to propagate, and the peeling of the fiber structure can be effectively suppressed.

The fineness of the first filamentous body (total fineness in the case of a multifilament yarn or the like) can be selected from the range of, for example, about 100 to 1000 dtex (for example, 200 to 900 dtex), preferably 300 to 800 dtex (for example, 400 to 700 dtex). More preferably, it may be about 500 to 600 dtex. When the lower limit of the fineness of the first filamentous body is in such a range, the effect of increasing the rigidity in the belt width direction (resistance to tensile force) can be sufficiently obtained, and it becomes easy to suppress the ring breakage. When the upper limit value of the fineness of the filamentous body is in such a range, the distance between the adjacent first filamentous bodies can be adjusted to an appropriate range, and it becomes easy to suppress the ring breakage.

From the viewpoint of effectively suppressing ring breakage, it is preferable that the first filaments adjacent to each other are arranged with a predetermined gap in the belt length direction. The gap between the first filaments adjacent to each other (the shortest distance in the belt length direction between the first filaments) is selected from the range of, for example, about 0.5 to 7.5 mm (for example, 0.8 to 6 mm). It may be preferably 1 to 5 mm (for example, 1.1 to 4.5 mm), more preferably 1.2 to 4 mm (for example, 1.3 to 3.5 mm), and particularly preferably 1.4 to 3 mm (for example, 1. It may be about 4 to 2.5 mm, particularly 1.4 to 2.1 mm). The range may be the range of the average value of the gap. When the upper limit of the gap between the first filaments is in such a range, the effect of increasing the rigidity (resistance to tensile force) in the belt width direction can be sufficiently obtained, and it becomes easy to suppress the ring breakage. When the lower limit of the density of the filament 1 is in such a range, even if the first filament is cut, it becomes difficult for the defect (crack or cut) to propagate continuously in the belt length direction. , There is a tendency to suppress ring breakage, and in particular, when the connecting reinforcing layer contains a rubber component (crosslinked rubber composition), the rubber component easily enters between the adjacent first filaments, and the defective portion. It seems that the stress acting on the vicinity and the like is dispersed in the rubber component, the defects are more difficult to propagate, and the peeling of the fiber structure can be effectively suppressed.

In the present application, the "gap" of threads (thread-like bodies) extending in the same direction in the fiber structure and adjacent to each other is the distance (shortest distance) from the surface of one thread to the surface of the other thread. means.

The first filament may have a predetermined cover factor (or coverage, hereinafter also referred to as CF) from the viewpoint of effectively suppressing ring breakage. The cover factor (CF) is an index showing the fineness of the thread (first filament) in the fiber structure [or how much the thread (first filament) covers the plane of the fiber structure]. Therefore, in the present application, it is expressed by the following formula.

CF = n × (N) ^1/2

[In the formula, n indicates the thread density [book / 50 mm] of the thread (first thread-like body), and N indicates the fineness (total fineness) [dtex] of the thread (first thread-like body). ]

The CF [unit: (book / 50 mm) × (dtex) ^1/2 ] of the first filament may be selected from the range of, for example, about 150 to 1200 (for example, 180 to 1100), preferably 200 to 1000. It may be (for example, 300 to 900), more preferably 400 to 800 (for example, 450 to 750), and particularly about 500 to 720. When the lower limit of CF of the first filamentous body is in such a range, the effect of increasing the rigidity (resistance to tensile force) in the belt width direction can be sufficiently obtained, and it becomes easy to suppress the ring breakage, and the first. When the upper limit of the density of the thread-like body is in such a range, even if the first thread-like body is cut, it becomes difficult for the defect (crack or cut) to propagate continuously in the belt length direction. There is a tendency to suppress ring breakage, and in particular, when the connecting reinforcing layer contains a rubber component (crosslinked rubber composition), the rubber component easily enters between the adjacent first filaments, and the vicinity of the defective portion. It seems that the stress acting on the rubber component is dispersed in the rubber component, the defect is more difficult to propagate, and the peeling of the fiber structure can be effectively suppressed.

The first filamentous yarn may be, for example, a spun yarn, a filament yarn, a composite yarn, etc., preferably a filament yarn (monofilament yarn, multifilament yarn, etc.), and more preferably a multifilament yarn.

When the first filamentous body is a multifilament yarn, the multifilament yarn may contain, for example, about 10 to 1000 filaments (for example, 30 to 700), and 50 to 500 yarns (for example, 60 to 300). ) May be contained, preferably 70 to 200 filaments (for example, 80 to 150), and more preferably 85 to 120 filaments (for example, 90 to 110).

The first thread-like body may be untwisted yarn or twisted yarn, but is preferably untwisted yarn or sweet-twisted yarn having a twist number of 1 to 29 times / 100 mm from the viewpoint of increasing the rigidity in the belt width direction. , Especially, non-twisted yarn is preferable. In a filamentous body having such a small number of twists, the adhesive component and the rubber component (crosslinked rubber composition), which will be described later, can easily permeate between the fibers, effectively improving the adhesiveness and suppressing the peeling of the fiber structure. Easy to do.

In the present application, the untwisted yarn means a yarn having a number of twists of 0 times / 100 mm or more (that is, including a yarn that is not twisted at all) and a yarn that is less than 1 time / 100 mm and is substantially untwisted.

The average diameter (diameter) of the first filamentous body may be, for example, about 0.01 to 3 mm (for example, 0.05 to 1 mm), preferably 0.08 to 0.5 mm (for example, 0.1 to 0). .4 mm), more preferably about 0.15 to 0.3 mm (for example, 0.2 to 0.25 mm).

The material of the first filament is not particularly limited, and for example, polyolefin fibers (polyethylene fibers, polypropylene fibers, etc.), vinyl alcohol fibers (polyvinyl alcohol fibers, ethylene-vinyl alcohol copolymer fibers, vinylon fibers, etc.), etc. ), Polyester fiber (polyalkylene allylate fiber, etc.), Polyamide fiber (polyamide 6 fiber, polyamide 66 fiber, aliphatic polyamide fiber such as polyamide 46 fiber, aramid fiber, etc.), Polyparaphenylene benzobisoxazole (PBO) Synthetic fibers such as fibers; Cellular fibers (cellulose fibers derived from natural plants, animals, bacteria, algae, etc .; cellulose ester fibers, fibers of cellulose derivatives such as regenerated cellulose fibers, etc.), natural fibers such as wool; carbon fibers, Inorganic fibers such as glass fiber and metal fiber can be used. These fibers may be single yarns used alone, or may be composite yarns (mixed yarns) in which two or more kinds are combined.

Among these fibers, from the viewpoint of excellent formability (productivity), fibers having high heat resistance, for example, the shape (or mechanical strength) as a filamentous body without being completely melted at the crosslinking temperature in the crosslinking step. It is preferable to include fibers that can be held to some extent [for example, fibers that are made of a material having a melting point or a softening point of 160 ° C. or higher (for example, about 170 to 200 ° C.)]. Examples of such highly heat-resistant fibers include inorganic fibers, polypropylene fibers (polypropylene fibers and the like), polyvinyl alcohol fibers, polyester fibers and at least one type of synthetic fibers selected from polyamide fibers. Be done. Therefore, the first filamentous body preferably contains these highly heat-resistant fibers (the synthetic fiber and / or the inorganic fiber), and more preferably the synthetic fiber (for example, a polyester fiber, an aramid fiber, or the like, a polyamide fiber). Fibers, etc.), especially polyester fibers are preferred.

The polyester fiber may be a polyalkylene allylate fiber. Examples of the polyalkylene allylate fiber include poly C _2-4 alkylene-C _8-14 allylate fiber such as polyethylene terephthalate (PET) fiber and polyethylene naphthalate (PEN) fiber.

The proportion of highly heat-resistant fibers (for example, polyester fibers, especially polyester fibers such as polyamide fibers such as aramid fibers) in the first filamentous body is, for example, 50% by mass or more (for example, 70 to 90% by mass). It may be preferably 90% by mass or more, and more preferably substantially 100% by mass. Within such a range, not only the effect of suppressing ring breakage but also the formability (productivity) tends to be improved.

The fiber structure may be formed in a substantially flat shape (sheet shape) and may include at least the first thread-like body, for example, a fiber in a suda record or a UD prepreg in which the thread is unidirectionally formed. Although it may be an aligned fiber structure, it is possible to stabilize the arrangement of a plurality of first filaments and efficiently orient them in the width direction of the belt, and to improve formability (handleability or productivity). , In addition to the first filament, a fibrous structure further comprising a plurality of second filaments that are at least connected (joined or interlaced) with the first filament and extend in a direction intersecting the belt width direction. Is preferable.

The thread density of the second thread-like body extending in a predetermined direction [direction in which the second thread-like bodies extending in the same direction are lined up (direction orthogonal to the extension direction of the second thread-like body, preferably belt width direction) per 50 mm. The number of threads] may be, for example, about 5 to 50 threads / 50 mm (for example, 8 to 45 threads / 50 mm), and has a higher density than the first thread-like body (for example, the spacing between the second thread-like bodies). It may be arranged without opening), but from the viewpoint of improving the flexibility of the belt, the thread density of the second thread-like body is as low as that of the first thread-like body (particularly, the thread density of the second thread-like body is that of the first thread-like body). The thread density is preferably less than or equal to), and can be selected from a range of, for example, about 10 to 39 threads / 50 mm (for example, 12 to 35 threads / 50 mm), and preferably 15 to 30 threads / 50 mm (for example, 18 to 27 threads / 50 mm). More preferably, it may be about 20 to 25 lines / 50 mm. The range may be the range of the average value of the yarn densities. When the lower limit of the density of the second filament is in such a range, the orientation and formability of the first filament in the belt width direction can be easily improved, and the upper limit of the density of the second filament can be improved. In such a range, not only is it easy to suppress the cutting of the thread at the contact point (intersection point or intersection point) with the first filamentous body, but also when the connecting reinforcing layer contains a rubber component (crosslinked rubber composition). The rubber component easily enters between the adjacent threads, and it seems that the peeling of the fiber structure can be effectively suppressed.

The fineness of the second filament (total fineness in the case of a multifilament yarn or the like) can be selected from the range of, for example, about 100 to 1000 dtex (for example, 200 to 900 dtex), preferably 300 to 800 dtex (for example, 400 to 700 dtex). More preferably, it may be about 500 to 600 dtex.

The arrangement form of the second filaments is not particularly limited, but from the viewpoint of improving the flexibility, formability, durability, etc. of the belt, the second filaments adjacent to each other are orthogonal to each other in the extending direction (for example,). , It is preferable to provide a predetermined gap in the belt width direction). The gap between the second filaments adjacent to each other (for example, the shortest distance in the belt width direction between the second filaments) is selected from the range of, for example, about 0.1 to 30 mm (for example, 0.3 to 20 mm). It may be selected from a range of, for example, about 0.5 to 10 mm (for example, 0.8 to 7.5 mm), preferably 1 to 5 mm (for example, 1.2 to 3 mm), and more preferably 1.3. It may be about 2.5 mm (for example, 1.4 to 2.1 mm). The range may be the range of the average value of the gap. When the upper limit value of the gap of the second thread-like body is in such a range, it becomes easy to improve the orientation and formability of the first thread-like body in the belt width direction, and the lower limit value of the gap of the second thread-like body is easy to improve. In such a range, not only is it easy to suppress the cutting of the thread at the contact point (intersection point or intersection point) with the first filamentous body, but also when the connecting reinforcing layer contains a rubber component (crosslinked rubber composition). The rubber component easily enters between the adjacent threads, and it seems that the peeling of the fiber structure can be effectively suppressed.

The second filament has no particular limitation on a predetermined cover factor (CF) [unit: (book / 50 mm) × (dtex) ^1/2 ], and is selected from a range of, for example, about 10 to 1500 (for example, 100 to 1300). It may be selected from the range of, for example, about 150 to 1200 (for example, 180 to 1100), and preferably 200 to 1000 (for example, 300) from the viewpoint of improving the flexibility, formability, durability and the like of the belt. ~ 900), more preferably 400 to 800 (for example, 450 to 750), and particularly preferably about 500 to 720. When the lower limit of CF of the second filament is in such a range, the orientation and formability of the first filament in the belt width direction can be easily improved, and the upper limit of CF of the second filament can be improved. In such a range, not only is it easy to suppress the cutting of the thread at the contact point (intersection point or intersection point) with the first filamentous body, but also when the connecting reinforcing layer contains a rubber component (crosslinked rubber composition). The rubber component easily enters between the adjacent threads, and it seems that the peeling of the fiber structure can be effectively suppressed.

The second filamentous yarn may be, for example, a spun yarn, a filament yarn, a composite yarn, etc., preferably a filament yarn (monofilament yarn, multifilament yarn, etc.), and more preferably a multifilament yarn.

When the second filamentous body is a multifilament yarn, the multifilament yarn may contain, for example, about 10 to 1000 filaments (for example, 30 to 700), and 50 to 500 yarns (for example, 60 to 300). ) May be contained, preferably 70 to 200 filaments (for example, 80 to 150), and more preferably 85 to 120 filaments (for example, 90 to 110).

The second filament may also be untwisted or twisted, but like the first filament, the number of twists is 0 times / 100 mm or more and less than 1 time / 100 mm, or the number of twists is 1 to 1. A sweet twisted yarn of 29 times / 100 mm is preferable, and a non-twisted yarn is particularly preferable. In a filamentous body having such a small number of twists, the adhesive component and the rubber component (crosslinked rubber composition), which will be described later, can easily permeate between the fibers, effectively improving the adhesiveness and suppressing the peeling of the fiber structure. Easy to do.

The average diameter (diameter) of the second filament may be, for example, about 0.01 to 3 mm (for example, 0.05 to 1 mm), preferably 0.08 to 0.5 mm (for example, 0.1 to 0). .4 mm), more preferably about 0.15 to 0.3 mm (for example, 0.2 to 0.25 mm).

The material of the second filamentous body is not particularly limited, and is the same as the preferred embodiment of the material of the first filamentous body, for example. Further, the proportion of fibers having high heat resistance (for example, polyester fibers, polyamide fibers such as aramid fibers, particularly polyester fibers) in the second filament is, for example, 50% by mass or more (for example, 70 to 70 to). 90% by mass), preferably 90% by mass or more, and more preferably substantially 100% by mass. Within such a range, the moldability (productivity) tends to be improved.

The second filament is not particularly limited as long as it extends in the direction intersecting the belt width direction, and may be formed extending in the belt (tie band) thickness direction, for example, but is formed in the back surface direction (tie band) of the belt. It is preferable to extend in the plane direction). The crossing angle between the second filament and the first filament may be, for example, about 20 to 160 ° (for example, 30 to 150 °), preferably 45 to 135 ° (for example, 60 to 120 °). More preferably, it is 75 to 105 ° (for example, 80 to 100 °, particularly a substantially right angle).

Further, the second thread-like body may be formed extending not only in a specific direction but also in a plurality of directions as long as it intersects in the belt width direction. That is, the fiber structure may be a multi-axis fiber structure formed of threads having three or more axes, such as a triaxial woven fabric, a triaxial net, and a honeycomb net (honeycomb mesh). From the point of view of availability or productivity, a biaxial fiber formed by a first filament extending in the belt width direction and a second filament extending in a specific one direction (preferably in the belt length direction). Structures (such as suda records, woven fabrics, or nets formed of warp and weft) are preferred.

In a suda record, woven fabric, or net formed of warp and weft, either the warp or weft may be used as the first thread-like body, and from the viewpoint of productivity, the weft is directed toward the belt width. It is preferable to use the filamentous body of 1. Further, when a net is formed by using the weft as the first thread and the warp as the second thread, the structure of the net is such as the fiber structure 2 shown in FIG. 1 in each weft 2a extending in the belt width direction. On the other hand, the structure may be such that the warps 2b arranged at intervals in the belt width direction are arranged alternately in the upper and lower parts; However, the former structure shown in FIG. 1 is preferable from the viewpoint of improving the flexibility of the belt.

As the fiber structure, a woven fabric or a net (net-like structure or mesh) formed by a first thread-like body and a second thread-like body is preferable, and among them, the strength of the tie band (bonding member) (machine). The net is more preferable in that it is easy to improve the characteristics). In particular, if the net is formed without weaving threads or tying threads (forming knots) (non-interlaced nets having no woven structure or knots), the serpentine of the thread-like body (or the above-mentioned song). It is easy to suppress the decrease in rigidity due to the portion), and there is a tendency that cutting due to wear or the like at the contact point (intersection point) between the first filamentous body and the second filamentous body can be suppressed. Typical nets include "Clenette (registered trademark)" manufactured by Kurabo Industries Ltd. and "Sof (registered trademark)" manufactured by Sumika Sekisui Film Co., Ltd.

Further, in the fiber structure (woven fabric or net, particularly the non-intersecting net), the contact point (intersection point) between the first filamentous body and the second filamentous body is bonded (bonded or bonded). preferable. When the contacts are connected, the relative arrangement such as the spacing between the filaments can be stabilized and the belt can be efficiently oriented in the width direction, and the formability can be improved. The form of bonding of the contacts is not particularly limited and may be fused by heat fusion or the like, but an adhesive (resin or the like) can be easily bonded regardless of the material of the thread and can improve productivity. It is preferable that they are bonded with. The adhesive is not particularly limited, and a conventional adhesive can be used, and may be the same as the adhesive component used for the adhesive treatment of the fiber structure described later.

The fiber structure is subjected to a conventional adhesive treatment (or surface treatment) [for example, treatment with a treatment liquid containing an adhesive component] in order to improve the adhesiveness with a rubber component (crosslinked rubber composition) or the like. You may. Examples of the adhesive component (or surface treatment agent) used in the adhesive treatment include isocyanate (polyisocyanate compound), epoxy resin (epoxy compound), silane coupling agent, amino resin, rubber latex or rubber glue, and resorcin (R). An RFL solution containing formaldehyde (F) and rubber or latex (L) [for example, resorcin (R) and formaldehyde (F) form a condensate (RF condensate), and the rubber component, for example, vinylpyridine-. RFL liquid containing styrene-butadiene copolymer rubber] and the like. These may be used alone or in combination of two or more, and may be sequentially treated with the same or different adhesive components multiple times. Among them, an adhesive component containing a rubber component of the same type (preferably the same) as the rubber component in the connecting reinforcing layer such as rubber latex (chloroprene latex or the like) is preferable.

The basis weight (weight) of the fiber structure is, for example, 10 to 120 g / m ² (for example, 20 to 100 g / m ² ), preferably 30 to 90 g / m ² (40 to 80 g / m ² ), and more preferably. It may be about 50 to 70 g / m ² . The average thickness of the fiber structure may be, for example, 0.1 to 1 mm, preferably 0.2 to 0.5 mm, and more preferably 0.25 to 0.3 mm.

Further, the connecting reinforcing layer may be provided with a plurality of layers (for example, 2 to 3 layers) of substantially flat (sheet-shaped) fiber structures as described above, but the flexibility and production of the belt may be provided. From the viewpoint of sex and the like, it is preferably one layer.

(Crosslinked rubber composition (rubber component))
The connecting reinforcing layer may contain at least a fiber structure, but it is preferable that the connecting reinforcing layer further contains a rubber component (crosslinked rubber composition), and it is particularly preferable that the fiber structure is embedded in the rubber component. When the rubber component intervenes between the filaments constituting the fiber structure, the peeling of the fiber structure can be effectively suppressed, and in particular, the rubber component intervenes between the first filaments adjacent to each other in the belt length direction. , The stress is dispersed in the rubber component, and it seems that the defect is more difficult to propagate.

The rubber hardness Hs of the crosslinked rubber composition forming the connecting reinforcing layer is, for example, 56 to 64 °, preferably 58 to 62 °, and more preferably 59 to 61 °. If the rubber hardness is too small, the durability may decrease, and conversely, if the rubber hardness is too large, the flexibility may decrease.

In the present application, the rubber hardness of each rubber layer was measured using a durometer A type hardness tester according to JIS K6253 (2012) (vulverized rubber and thermoplastic rubber-how to determine the hardness-). It indicates a value Hs (JIS A) and may be simply described as rubber hardness.

The tensile elastic modulus (modulus) of the crosslinked rubber composition forming the connecting reinforcing layer is, for example, 10 to 25 MPa, preferably 15 to 20 MPa, and more preferably 16 to 18 MPa. If the tensile modulus is too small, the durability may decrease, and if it is too large, the flexibility may decrease.

In the present application, the tensile elastic modulus (modulus) of each rubber layer can be measured by a method according to JIS K6251 (2017).

The rubber component constituting the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be selected from known vulverable or crosslinkable rubbers and / or elastomers, for example, diene rubber [natural rubber, isoprene rubber, Butadiene rubber, chloroprene rubber (CR), styrene butadiene rubber (SBR), vinylpyridine-styrene-butadiene copolymer rubber, acrylonitrile butadiene rubber (nitrile rubber); hydride nitrile rubber (hydride nitrile rubber and unsaturated carboxylate metal) (Including mixed polymer with salt), etc.], olefin rubber [for example, ethylene-α-olefin rubber (ethylene-α-olefin elastomer), polyoctenylene rubber, ethylene- Vinyl acetate copolymer rubber, chlorosulfonated polyethylene rubber, alkylated chlorosulfonated polyethylene rubber, etc.], epichlorohydrin rubber, acrylic rubber, silicone rubber, urethane rubber, fluororubber, etc. can be exemplified. These rubber components can be used alone or in combination of two or more.

Of these, ethylene-α-olefin elastomer [ethylene-propylene copolymer (EPM), ethylene-propylene-diene ternary copolymer (EPDM), etc.) are used because the vulcanizing agent and vulcanization accelerator are easily diffused. Ethylene-α-olefin rubber] and chloroprene rubber are widely used, and especially when used in a high load environment, they have an excellent balance of mechanical strength, weather resistance, heat resistance, cold resistance, oil resistance, adhesiveness, etc. , Chloroprene rubber, EPDM are preferred. Further, chloroprene rubber is particularly preferable because it is excellent in wear resistance in addition to the above-mentioned characteristics. The chloroprene rubber may be a sulfur-modified type or a non-sulfur-modified type.

When the rubber component contains chloroprene rubber, the proportion of chloroprene rubber in the rubber component may be, for example, 50% by mass or more (particularly about 80 to 100% by mass), and 100% by mass (only chloroprene rubber) is particularly preferable.

The crosslinked rubber composition of the connecting reinforcing layer may further contain a filler in addition to the rubber component. Examples of the filler include carbon black, silica, clay, calcium carbonate, talc, mica and the like. The filler often contains a reinforcing filler, and such a reinforcing filler may be carbon black, reinforcing silica, or the like. In addition, the reinforcing property of silica is usually smaller than the reinforcing property of carbon black. These fillers can be used alone or in combination of two or more. Among these fillers, it is preferable to contain a reinforcing filler, and it is particularly preferable to contain carbon black.

The average particle size (number average primary particle size) of carbon black is, for example, 5 to 200 nm, preferably 10 to 150 nm, more preferably about 15 to 100 nm, and even if the particle size is small, the reinforcing effect is high. It may be, for example, 5 to 38 nm, preferably 10 to 35 nm, and more preferably about 15 to 30 nm. Examples of the carbon black having a small particle size include SAF, ISAF-HM, ISAF-LM, HAF-LS, HAF, HAF-HS and the like. These carbon blacks can be used alone or in combination of two or more.

The ratio of the filler (particularly carbon black) is, for example, 1 to 100 parts by mass, preferably 10 to 70 parts by mass, and more preferably 20 to 60 parts by mass (particularly 30 to 50 parts by mass) with respect to 100 parts by mass of the rubber component. It may be a degree. If the proportion of the filler is too small, the elastic modulus may be insufficient and the durability may be lowered, and if it is too large, the elastic modulus may be too high and the flexibility may be lowered.

The crosslinked rubber composition of the connecting reinforcing layer may contain other additives such as short fibers (eg, polyolefin fibers, polyamide fibers, polyalkylene allylate fibers, polyvinyl alcohol fibers, polyparaphenylene benzobis) as required. Synthetic fibers such as oxazole (PBO) fibers; natural fibers such as cotton, linen and wool; inorganic fibers such as carbon fibers), vulcanizing agents or cross-linking agents, co-crosslinking agents (crosslinking aids or co-vulcanizing agents co- agent) [eg, polyfunctional (iso) cyanurate, polydiene, metal salts of unsaturated carboxylic acids, oximes, guanidines, polyfunctional (meth) acrylates, bismaleimides, etc.], vulcanization aids or cross-linking aids, Vulcanization accelerator or crosslink accelerator, vulcanization retarder or crosslink retarder, metal oxide (calcium oxide, barium oxide, iron oxide, copper oxide, titanium oxide, aluminum oxide, etc.), softener (paraffin oil, naphthen type) Oils such as oils), processing agents or processing aids, adhesion improvers [eg, resorcin-formaldehyde cocondensates (RF condensates), amino resins (condensations of nitrogen-containing cyclic compounds and formaldehyde, eg) Hexamethylol melamine, melamine resin such as hexaalkoxymethyl melamine (hexamethoxymethyl melamine, hexabutoxymethyl melamine, etc.), urea resin such as methylol urea, benzoguanamine resin such as methylol benzoguanamine resin, etc.), vulcanized products thereof (resolcin- Melamine-formaldehyde cocondensate, etc.)], anti-aging agents (antioxidants, heat anti-aging agents, bending crack inhibitors, ozone deterioration inhibitors, etc.), colorants, tackifiers, plasticizers, lubricants, cups, etc. It may contain a ring agent (silane coupling agent, etc.), a stabilizer (ultraviolet absorber, heat stabilizer, etc.), a flame retardant, an antistatic agent, and the like. The metal oxide may act as a cross-linking agent. Further, in the adhesiveness improving agent, the resorcin-formaldehyde cocondensate and the amino resin may be an initial condensate (prepolymer) of a nitrogen-containing cyclic compound such as resorcin and / or melamine and formaldehyde.

These other additives can also be used alone or in combination of two or more. Of these, the connecting reinforcing layer contains, in addition to the rubber component, a vulcanization agent or a cross-linking agent, a vulcanization accelerator or a cross-linking accelerator, a processing agent or a processing aid, an antiaging agent, and a plasticizer. preferable.

As the vulcanizing agent or the cross-linking agent, conventional components can be used depending on the type of rubber component. For example, the metal oxide cross-linking agent (magnesium oxide, zinc oxide, lead oxide, etc.) and organic peroxide (diacylper) can be used. Oxides, peroxyesters, dialkyl peroxides, etc.), sulfur-based vulcanizers, etc. can be exemplified. Examples of the sulfur-based sulfurizing agent include powdered sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, highly dispersible sulfur, and sulfur chloride (sulfur monochloride, sulfur dichloride, etc.). These cross-linking agents or vulcanizing agents can be used alone or in combination of two or more. When the rubber component is chloroprene rubber, a metal oxide (magnesium oxide, zinc oxide, etc.) may be used as a vulcanizing agent or a cross-linking agent. The metal oxide may be used in combination with another vulcanizing agent (sulfur-based vulcanizing agent, etc.), and the metal oxide and / or the sulfur-based vulcanizing agent may be used alone or with a vulcanization accelerator. It may be used in combination.

The ratio of the vulcanizing agent or the cross-linking agent can be selected from the range of, for example, about 1 to 20 parts by mass with respect to 100 parts by mass of the rubber component in terms of solid content, depending on the type of the vulcanizing agent or the cross-linking agent and the rubber component. .. For example, the ratio of the metal oxide as a cross-linking agent is, for example, 1 to 20 parts by mass, preferably 3 to 17 parts by mass, and more preferably 5 to 15 parts by mass (particularly 7 to 13) with respect to 100 parts by mass of the rubber component. By mass). When the metal oxide and the sulfur-based vulcanizer are combined, the ratio of the sulfur-based vulcanizer is, for example, 0.1 to 50 parts by mass, preferably 1 to 30 parts by mass with respect to 100 parts by mass of the metal oxide. More preferably, it is about 3 to 10 parts by mass. The ratio of the organic peroxide is, for example, 1 to 8 parts by mass, preferably 1.5 to 5 parts by mass, and more preferably 2 to 4.5 parts by mass with respect to 100 parts by mass of the rubber component.

Examples of the vulcanization accelerator or the cross-linking accelerator include thiuram-based accelerators [eg, tetramethylthiuram monosulfide (TMTM), tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide (TETD), tetrabutylthium). -Disulfide (TBTD), dipentamethylene thiuram tetrasulfide (DPTT), N, N'-dimethyl-N, N'-diphenylthium disulfide, etc.], thiazol-based accelerators [eg, 2-mercaptobenzothiazo] -L, 2-mercaptobenzothiazol zinc salt, 2-mercaptothiazolin, dibenzothiadyl-disulfide, 2- (4'-morpholinodithio) benzothiazole, etc.], sulfur amide-based accelerator [eg, N -Cyclohexyl-2-benzothiadylsulfenamide (CBS), N, N'-dicyclohexyl-2-benzothiadylsulfenamide, etc.], guanidines (diphenylguanidine, dio-tolylguanidine, etc.), ureas Alternatively, thiourea-based accelerators (eg, ethylenethiourea, etc.), dithiocarbamates, xanthogenates, etc. may be mentioned. These vulcanization accelerators can be used alone or in combination of two or more. Among these vulcanization accelerators, TMTD, DPTT, CBS and the like are widely used.

The ratio of the vulture accelerator or the cross-linking accelerator is, for example, 0.1 to 15 parts by mass, preferably 0.3 to 10 parts by mass (for example, 0.5 to 0.5 to 5 parts by mass) with respect to 100 parts by mass of the rubber component in terms of solid content. 5 parts by mass), more preferably about 0.5 to 3 parts by mass (particularly 0.5 to 1.5 parts by mass).

Examples of the processing agent or processing aid include fatty acids such as stearic acid, fatty acid metal salts such as stearic acid metal salts, fatty acid amides such as stearic acid amide, waxes, paraffins and the like.

The ratio of the processing agent or processing aid (such as stearic acid) is, for example, 10 parts by mass or less (for example, 0 to 10 parts by mass), preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the rubber component in terms of solid content. It is about 1 to 3 parts by mass (for example, 0.5 to 3 parts by mass), more preferably 1 to 3 parts by mass (particularly 1.5 to 2.5 parts by mass).

The ratio of the anti-aging agent is, for example, 0.5 to 15 parts by mass, preferably 1 to 10 parts by mass, and more preferably 2.5 to 7.5 parts by mass with respect to 100 parts by mass of the rubber component in terms of solid content. (Especially 3 to 7 parts by mass).

Examples of the plasticizer include an aliphatic carboxylic acid-based plasticizer (adipic acid ester-based plasticizer, sebacic acid ester-based plasticizer, etc.) and an aromatic carboxylic acid ester-based plasticizer (phthalic acid ester-based plasticizer, trimellitic acid). Ester-based plasticizers, etc.), oxycarboxylic acid ester-based plasticizers, phosphoric acid ester-based plasticizers, ether-based plasticizers, ether ester-based plasticizers, and the like. These plasticizers can be used alone or in combination of two or more. Of these, ether ester-based plasticizers are preferable.

The ratio of the plasticizer is, for example, 1 to 30 parts by mass, preferably 3 to 20 parts by mass, and more preferably 3 to 10 parts by mass (particularly 3 to 8 parts by mass) with respect to 100 parts by mass of the rubber component.

The average thickness of the connecting reinforcing layer is, for example, 0.1 to 2 mm, preferably 0.3 to 1.5 mm, and more preferably about 0.5 to 1 mm. If the thickness of the connecting reinforcing layer is too thin, the effect of suppressing ring breakage may decrease, and if it is too thick, the bending fatigue resistance (flexibility) of the belt may decrease.

Further, the tie band (bonding member) may be provided with a plurality of connecting reinforcing layers (for example, 2 to 3 layers) as described above, if necessary, but from the viewpoint of belt flexibility and productivity. , Preferably one layer.

[Protective layer]
The tie band (bonding member) may be formed only by the connecting reinforcing layer, but it is connected because damage to the fiber structure in the connecting reinforcing layer (for example, damage caused by foreign matter from the back surface of the belt) can be effectively suppressed. A protective layer laminated on the reinforcing layer (the outer peripheral surface side of the belt or the outermost layer) may be provided.

The protective layer is a rubber sheet (preferably rubber containing at least short fibers) of a conventional crosslinked rubber composition [for example, a composition containing a rubber component exemplified as a crosslinked rubber composition which may be contained in the connecting reinforcing layer]. It may be formed of a rubber sheet of the composition) or may be formed of a conventional cloth. These protective layers may be used alone or in combination of two or more. Of these protective layers, a protective layer made of cloth is preferable.

Examples of the cloth include woven cloth, knitted cloth (weft knitted cloth, warp knitted cloth), and cloth materials such as non-woven fabric. Of these, woven fabrics woven in the form of plain weave, twill weave, red weave, etc., woven fabrics woven at a wide angle where the crossing angle between the warp and weft yarns exceeds 90 ° and 120 ° or less are preferable. Weave cloth that is widely used as a cover cloth for transmission belts for general industry and agricultural machinery [plain weave cloth with a right angle of intersection between warp and weft, and cross angle between warp and weft exceeds 90 ° and 120 °. Plain weave cloth (wide-angle woven cloth) having a wide angle of the following degree] is particularly preferable.

When the protective layer contains a cloth (particularly a woven cloth), the threads constituting the cloth are arranged so as to be diagonal to the belt width direction (for example, an angle of about 15 ° or more with respect to the belt width direction). In particular, when the fabric is a woven fabric composed of warps and wefts, the direction in which the warps and wefts extend is substantially bilaterally symmetrical with respect to the belt length direction (division of the intersection angle of the warps and wefts into two equal parts). It is preferable to arrange the wires so that they are substantially parallel to the length of the belt). When the protective layer arranged in this way is combined with the connecting reinforcing layer, the fiber structure is effectively protected to suppress ring breakage, and the elasticity in the belt length direction is secured to vibrate, overturn, and detach the belt. It is easy to suppress such things, and the durability of the belt can be further improved, and there is a tendency that the belt can be transmitted more efficiently.

Examples of the fibers constituting the fabric include polyolefin fibers (polyethylene fibers, polypropylene fibers, etc.), polyamide fibers (polyamide 6 fibers, polyamide 66 fibers, polyamide 46 fibers, aramid fibers, etc.), and polyester fibers (poly). Synthetic fibers such as alkylene allylate fibers), vinyl alcohol fibers (polyvinyl alcohol fibers, ethylene-vinyl alcohol copolymer fibers, vinylon fibers, etc.), polyparaphenylene benzobisoxazole (PBO) fibers; cellulose fibers (cellulose) (Fibers, fibers of cellulose derivatives, etc.), natural fibers such as wool; inorganic fibers such as carbon fibers are widely used. These fibers may be single yarns used alone, or may be composite yarns (blended yarns, etc.) in which two or more kinds are combined.

Among these fibers, a blended yarn of a polyester fiber and a cellulosic fiber is preferable from the viewpoint of excellent mechanical properties and economic efficiency.

The polyester fiber may be a polyalkylene allylate fiber. Examples of the polyalkylene allylate fiber include poly C _2-4 alkylene-C _8-14 allylate fiber such as polyethylene terephthalate (PET) fiber and polyethylene naphthalate (PEN) fiber. These polyester fibers can also be used alone or in combination of two or more.

Cellulose-based fibers include cellulosic fibers (cellulose fibers derived from plants, animals, bacteria, etc.) and fibers of cellulose derivatives. Examples of cellulose fibers include wood pulp (coniferous tree, broadleaf tree pulp, etc.), bamboo fiber, sugar cane fiber, seed hair fiber (cotton fiber (cotton linter), capoc, etc.), ginseng fiber (hemp, kozo, mitsumata, etc.), Cellulose fibers derived from natural plants (pulp fibers) such as leaf fibers (Manila hemp, New Zealand hemp, etc.); cellulose fibers derived from animals such as squirrel cellulose; bacterial cellulose fibers; cellulose of algae and the like can be exemplified. Examples of the fibers of the cellulose derivative include cellulose ester fibers; regenerated cellulose fibers (rayon, cupra, lyocell, etc.). These cellulosic fibers can also be used alone or in combination of two or more. Of these, cotton fibers are preferred.

The mass ratio of the polyester fiber to the cellulosic fiber is, for example, the former / the latter = 90/10 to 10/90, preferably 80/20 to 20/80, and more preferably 70/30 to 30/70 (particularly 60 /). It is about 40 to 40/60).

The average fineness of the threads constituting the woven fabric is, for example, 5 to 30 counts, preferably 10 to 25 counts, and more preferably 10 to 20 counts.

The basis weight of the fabric (raw material fabric) is, for example, 100 to 500 g / m ² , preferably 200 to 400 g / m ² , and more preferably 250 to 350 g / m ² .

The average thickness of the cloth (raw material cloth) is, for example, 0.1 to 1.5 mm, preferably 0.2 to 1 mm, and more preferably about 0.3 to 0.7 mm.

When the cloth (raw material cloth) is a woven cloth, the thread density (density of warp and weft) of the cloth is, for example, 60 to 100 threads / 50 mm, preferably 70 to 90 threads / 50 mm, and more preferably 75 to 85 threads / 50 mm. Degree.

The protective layer may be a woven fabric to which a rubber component (rubber composition) is attached in order to improve the adhesiveness with the connecting reinforcing layer. The cloth to which the rubber component is attached is, for example, a cloth that has been subjected to an adhesive treatment such as a treatment of soaking (immersing) a rubber glue in which a rubber composition is dissolved in a solvent, or a treatment of friction (rubbing) a solid rubber composition. There may be. The adhesive treatment may be performed by treating at least one surface of the fabric, preferably at least the surface in contact with the connecting reinforcing layer, and particularly preferably both sides.

The rubber hardness Hs of the rubber composition used for the adhesive treatment of the protective layer is, for example, 50 to 60 °, preferably 52 to 56 °, and more preferably 53 to 55 °. If the rubber hardness is too small, the durability may decrease, and conversely, if the rubber hardness is too large, the flexibility may decrease.

The tensile elastic modulus (modulus) of the rubber composition used for the adhesive treatment of the protective layer is, for example, about 5 to 20 MPa, preferably 10 to 15 MPa, and more preferably about 11 to 13 MPa. If the tensile modulus is too small, the durability may decrease, and if it is too large, the flexibility may decrease.

The rubber component in the rubber composition used for the adhesive treatment of the protective layer is the same as the rubber component exemplified as the crosslinked rubber composition of the connecting reinforcing layer, including preferable embodiments.

The rubber composition used for the adhesive treatment of the protective layer may further contain a filler in addition to the rubber component. As the filler, the filler exemplified as the crosslinked rubber composition of the connecting reinforcing layer can be used. These fillers can be used alone or in combination of two or more. Among these fillers, it is preferable to contain a reinforcing filler, and it is particularly preferable to contain carbon black.

The ratio of the filler (particularly carbon black) is, for example, 5 to 80 parts by mass, preferably 10 to 75 parts by mass, and more preferably 30 to 70 parts by mass (particularly 40 to 60 parts by mass) with respect to 100 parts by mass of the rubber component. Degree. If the proportion of the filler is too small, the elastic modulus may be insufficient and the durability may be lowered, and if it is too large, the elastic modulus may be too high and the flexibility may be lowered.

The rubber composition used for the adhesive treatment of the protective layer may contain other additives, for example, other additives exemplified as the crosslinked rubber composition of the connecting reinforcing layer, if necessary. These other additives can also be used alone or in combination of two or more. Of these, the rubber composition used for the adhesive treatment of the protective layer contains a vulcanization agent or a cross-linking agent, a vulcanization accelerator or a cross-linking accelerator, a processing agent or a processing aid, an antiaging agent, and a plasticizer. preferable.

The proportions of the vulcanizing agent or the cross-linking agent, the vulcanization accelerator or the cross-linking accelerator, and the anti-aging agent are the same including the range exemplified as the cross-linked rubber composition of the connecting reinforcing layer and the preferable embodiment, respectively.

The ratio of the processing agent or processing aid (such as stearic acid) is, for example, 10 parts by mass or less (for example, 0 to 5 parts by mass), preferably 0.1 to 3 parts by mass, relative to 100 parts by mass of the rubber component in terms of solid content. It is about 0.3 to 2 parts by mass (particularly 0.5 to 1.5 parts by mass) by mass.

The ratio of the plasticizer (ether ester-based plasticizer, etc.) is, for example, 3 to 50 parts by mass, preferably 5 to 40 parts by mass, and more preferably 10 to 30 parts by mass (particularly 15 to 15 to 30 parts by mass) with respect to 100 parts by mass of the rubber component. About 25 parts by mass).

The average thickness of the protective layer is, for example, 0.4 to 2 mm, preferably 0.5 to 1.4 mm, and more preferably about 0.6 to 1.2 mm. If the thickness of the protective layer is too thin, the effect of suppressing damage to the fiber structure may be reduced, and if it is too thick, the flexibility of the belt may be reduced.

Further, the direction of the threads constituting the cloth (or the direction of the cloth) is not particularly limited, but it is preferable to arrange the threads diagonally with respect to the belt width direction.

The tie band (bonding member) may be provided with a plurality of layers (for example, 2 to 3 layers) as described above, if necessary, but is preferably one layer.

[V-belt part]
The V-belt portion connected to the tie band (coupling member) is not particularly limited, and in addition to the V-belt portion shown in FIG. 1, a conventional V-belt portion, that is, a core body including a core body (core wire) is included. It includes a layer (adhesive rubber layer), an stretch layer (stretch rubber layer) laminated on the outer peripheral side of the belt of the core body layer, and a compressed rubber layer laminated on the inner peripheral side of the belt of the core body layer, and is endless. It suffices to have a V-shaped cross section. The left and right sides of the V-shaped cross section are friction transmission surfaces, and in the V-shaped cross section, the side with a wide belt width is the outer peripheral side, and the side with a narrow belt width is the inner peripheral side.

Conventional V-belts include, for example, a wrapped V-belt in which the entire surface of the belt including the friction transmission surface is covered with an outer cover cloth (cover cloth), and a low-edge V-belt in which the transmission surface is not covered. (Including low-edge cogged V-belt) and the like. In applications such as agricultural machinery, the belt and the entire transmission mechanism are easily damaged by the high coefficient of friction of the transmission surface and the stress or impact caused by the entrainment of waste straw, stones, wood, etc., so the transmission surface can be used as a V-belt. Wrapped V-belts, which have a low coefficient of friction and can alleviate stress or impact with moderate slippage, are often used. In such a high load application, high rigidity (side pressure resistance) in the belt width direction is also required in order to prevent buckling deformation (dishes). Therefore, for the V-belt portion, for example, Japanese Patent Application Laid-Open No. 2020-3061. The wrapped V-belt portion having excellent lateral pressure resistance, that is, the compressed rubber layer has a laminated structure including two types of compressed rubber layers having different rubber hardness, and the rubber hardness of each layer is adjusted. It may be a department or the like. When the V-belt portion having excellent lateral pressure resistance is combined with the tie band, the ring breakage suppressing effect can be further improved.

Specifically, FIG. 2 shows a schematic cross-sectional view of an example of the V-belt portion constituting the coupled V-belt of the present invention (a drawing in which the tie band is omitted and only the V-belt portion is close-up). In the wrapped V-belt portion V1 shown in FIG. 2, from the outer peripheral side of the belt, the stretch rubber layer 14, the core body 15 is embedded in the vulture rubber composition, and the core body layer (adhesive rubber layer) 16 and the first compressed rubber layer are formed. An endless belt body in which 17a and a second compressed rubber layer 17b are sequentially laminated, and an outer cover cloth 18 (woven fabric, knitted fabric, non-woven fabric, etc.) that covers the circumference of the belt body over the entire length in the circumferential direction of the belt. , The second compressed rubber layer 17b and the reinforcing cloth layer 19 interposed between the outer cloth 18.

In this example, the core layer 16 is formed of a vulcanized rubber composition in which the core 15 is embedded, but the core layer is arranged at the interface between the stretched rubber layer and the compressed rubber layer. It may be formed only by the core body. In the present application, when the core body layer is formed only of the core body, the core bodies arranged at intervals in the belt body are referred to as a core body layer, and in such a core body layer, the core body is stretched. Not only the form arranged at the interface between the rubber layer and the compressed rubber layer, but also a part or all of the core body arranged at the interface between the stretched rubber layer and the compressed rubber layer is the stretched rubber layer or the stretched rubber layer in the manufacturing process. The form embedded in the compressed rubber layer is also included.

The components and materials of each component of the V-belt portion [first compressed rubber layer, second compressed rubber layer, stretched rubber layer, core body layer (adhesive rubber layer, core body), outer cover cloth, reinforcing cloth layer, etc.] (Rubber composition, core cord, cloth, etc.) and their ratio, thickness and characteristics of each layer (hardness Hs of each rubber layer and its relationship, tensile elastic modulus (modulus), etc.), and combinations thereof are special. It is the same including the examples and preferable embodiments described in Japanese Patent Publication No. 2020-3061.

[Compressed rubber layer]
The compressed rubber layer is a crosslinked rubber composition conventionally used as a rubber composition of a V-belt [for example, a composition containing a rubber component exemplified as a crosslinked rubber composition which may be contained in the connecting reinforcing layer, etc. ] May be formed.

The compressed rubber layer constituting each V-belt portion may be one layer as shown in FIG. 1, but the first compressed rubber layer laminated on the outer peripheral side of the belt and the rubber than the first compressed rubber layer. It is preferable to have a laminated structure having two or more layers including a second compressed rubber layer laminated on the inner peripheral side of the belt, which has a low hardness, and the rubber hardness of the stretched rubber layer is higher than the rubber hardness of the second compressed rubber layer. By adjusting the rubber hardness of the first compressed rubber layer to be higher than the rubber hardness of the stretchable rubber layer, the lateral pressure resistance of the bonded V-belt can be improved.

The compressed rubber layer may include a first compressed rubber layer and a second compressed rubber layer, and may have a laminated structure of three or more layers. However, from the viewpoint of lateral pressure resistance and productivity, the first compression is performed. A two-layer structure including a rubber layer and a second compressed rubber layer is preferable.

The rubber hardness of the first compressed rubber layer is equal to or higher than the rubber hardness of the stretched rubber layer, and the difference in rubber hardness Hs (JIS A) between the first compressed rubber layer and the stretched rubber layer (rubber hardness of the first compressed rubber layer- The rubber hardness of the stretched rubber layer) may be 0 ° or more. The rubber hardness of the first compressed rubber layer is preferably higher than the rubber hardness of the stretched rubber layer. The difference in rubber hardness Hs (JIS A) between the first compressed rubber layer and the stretched rubber layer can be selected from, for example, in the range of 0 to 10 ° from the viewpoint of achieving both lateral pressure resistance and flexibility of the belt. From the viewpoint of improving the side pressure resistance of the belt, it is preferably 0 to 7 °, more preferably 0 to 5 ° (for example, 0 to 4 °), and further preferably 0 to 3 ° (particularly 0 to 1 °). .. If the difference in rubber hardness between the two layers is too large, the rubber hardness of the stretched rubber layer decreases, which may reduce the lateral pressure resistance.

The rubber hardness Hs of the first compressed rubber layer can be selected from, for example, in the range of about 80 to 100 °, preferably 85 to 95 °, more preferably 87 to 93 °, still more preferably 88 to 92 ° (particularly 89 to 91 °). °). If the rubber hardness is too small, the lateral pressure resistance may decrease, and if it is too large, the fit and flexibility with the pulley groove may decrease.

The rubber hardness Hs of the second compressed rubber layer is lower than the rubber hardness of either the first compressed rubber layer or the stretched rubber layer, and the difference in the rubber hardness Hs between the first compressed rubber layer and the second compressed rubber layer (first). The rubber hardness of the compressed rubber layer − the rubber hardness of the second compressed rubber layer) may be, for example, 1 ° or more (particularly 5 ° or more), preferably 5 to 30 ° (for example, 7 to 27 °), and more preferably. It is about 10 to 25 ° (for example, 12 to 20 °), more preferably 14 to 20 ° (for example, 15 to 19 °), and most preferably about 14 to 17 ° (particularly 15 to 17 °). The difference in rubber hardness Hs between the stretched rubber layer and the second compressed rubber layer (rubber hardness of the stretched rubber layer-rubber hardness of the second compressed rubber layer) is also the rubber hardness between the first compressed rubber layer and the second compressed rubber layer. It can be selected from the same range as the difference in Hs. If the difference in rubber hardness between the second compressed rubber layer and the first compressed rubber layer or the stretchable rubber layer is too small, the flexibility may decrease.

The rubber hardness Hs of the second compressed rubber layer can be selected from, for example, in the range of about 60 to 90 °, preferably 65 to 80 °, more preferably 68 to 76 °, still more preferably 70 to 74 °, and most preferably 71. It is about 73 °. If the rubber hardness is too small, the lateral pressure resistance may decrease, and if it is too large, the flexibility may decrease.

The tensile elastic modulus (modulus) of the first compressed rubber layer is, for example, about 25 to 50 MPa, preferably 25 to 40 MPa, and more preferably 26 to 35 MPa (particularly 28 to 32 MPa) in the belt width direction. If the tensile modulus is too small, the lateral pressure resistance may decrease, and if it is too large, the flexibility may decrease.

The tensile elastic modulus (modulus) of the second compressed rubber layer is, for example, 12 to 20 MPa, preferably 13 to 18 MPa, and more preferably 14 to 17 MPa in the belt width direction. If the tensile modulus is too small, the lateral pressure resistance may decrease, and if it is too large, the flexibility may decrease.

The average thickness of the entire compressed rubber layer is, for example, 1 to 12 mm, preferably 2 to 10 mm, more preferably 2.5 to 9 mm (particularly 3 to 5 mm).

The average thickness of the first compressed rubber layer can be selected from the range of, for example, about 95 to 30% with respect to the average thickness of the entire compressed rubber layer, preferably 90 to 50%, more preferably 85 to 55%, still more preferably. Is about 80 to 60% (particularly 75 to 70%). This ratio may be the ratio when the compressed rubber layer is composed of only the first compressed rubber layer and the second compressed rubber layer (that is, L2 / L1 in FIG. 2). If the thickness ratio of the first compressed rubber layer is too small, the lateral pressure resistance may decrease, and conversely, if it is too large, the flexibility may decrease.

The compressed rubber layer may further include other compressed rubber layers having different rubber hardness in addition to the first compressed rubber layer and the second compressed rubber layer. The other compressed rubber layer may be a single layer or a plurality of layers. Further, the other compressed rubber layer may be laminated on either the upper or lower surface of the first compressed rubber layer or the lower surface of the second compressed rubber layer. The average thickness of the other compressed rubber layers may be, for example, 30% or less, preferably 10% or less, and more preferably 5% or less with respect to the average thickness of the entire compressed rubber layer. That is, the compressed rubber layer preferably includes the first compressed rubber layer and the second compressed rubber layer as the main layers, and the total average thickness of the first compressed rubber layer and the second compressed rubber layer is the compressed rubber layer. For example, it may be 70% or more, preferably 90% or more, more preferably 95% or more with respect to the total average thickness, and the compressed rubber layer is from only the first compressed rubber layer and the second compressed rubber layer. Is particularly preferable.

The compressed rubber layer may be formed of a crosslinked rubber composition conventionally used as a rubber composition of a V-belt. The crosslinked rubber composition may be a crosslinked rubber composition containing a rubber component, and by appropriately adjusting the composition of the composition, each layer constituting the compressed rubber layer, particularly the first compressed rubber layer and the second compressed rubber. The rubber hardness of the layer can be adjusted. The method for adjusting the rubber hardness and the like is not particularly limited, and the composition and / or type of the components constituting the composition may be changed and adjusted, and from the viewpoint of convenience and the like, the ratio of the short fibers and the filler and / Alternatively, it is preferable to change the type for adjustment.

(1st compression rubber layer)
The rubber component constituting the crosslinked rubber composition forming the first compressed rubber layer is the same as the rubber component exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer, including preferable embodiments. , Chloroprene rubber is particularly preferred.

When the rubber component contains chloroprene rubber, the proportion of chloroprene rubber in the rubber component may be, for example, 50% by mass or more (particularly about 80 to 100% by mass), and 100% by mass (only chloroprene rubber) is particularly preferable.

The crosslinked rubber composition forming the first compressed rubber layer may further contain staple fibers in addition to the rubber component. Examples of the short fibers include the material of the first filament and the fibers exemplified as the fibers constituting the fabric of the protective layer. These staple fibers can be used alone or in combination of two or more. Among these short fibers, rigid, high-strength and modulus fibers such as polyester fibers (particularly polyethylene terephthalate fibers and polyethylene naphthalate fibers) and polyamide fibers (particularly aramid fibers) are preferable. Aramid fibers also have high wear resistance. Therefore, the staple fibers preferably contain at least total aromatic polyamide fibers such as aramid fibers. Aramid fiber is a commercial product with trade names such as "Conex (registered trademark)", "Nomex (registered trademark)", "Kevlar (registered trademark)", "Technora (registered trademark)", and "Twaron (registered trademark)". May be.

The average fiber diameter of the short fibers is, for example, 2 μm or more, preferably about 5 to 100 μm. The average length of the short fibers is, for example, about 1 to 20 mm, preferably about 1.5 to 10 mm.

From the viewpoint of dispersibility and adhesiveness of the short fibers in the rubber composition, the short fibers are subjected to a conventional adhesive treatment (or surface treatment) [for example, an adhesive treatment of the fiber structure exemplified in the section of the connecting reinforcing layer]. May be applied.

The staple fibers may be oriented in the belt width direction and embedded in the compressed rubber layer in order to suppress the compression deformation of the belt due to the pressure from the pulley.

The ratio of the short fibers is, for example, about 5 to 50 parts by mass, preferably about 10 to 30 parts by mass with respect to 100 parts by mass of the rubber component. If the proportion of the short fibers is too small, the rubber hardness of the first compressed rubber layer may decrease, and if it is too large, the flexibility may decrease.

The crosslinked rubber composition forming the first compressed rubber layer may further contain a filler in addition to the rubber component. Examples of the filler include the same fillers as those exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer, including preferable embodiments, and in order to improve lateral pressure resistance, a reinforcing filler may be used. It is preferable to contain carbon black, and it is particularly preferable to contain carbon black.

Since deterioration of workability can be suppressed even if a large amount of carbon black is blended, the mechanical properties (elastic modulus) of the first compressed rubber layer can be improved. Further, carbon black can reduce the coefficient of friction of the first compressed rubber layer and can improve the wear resistance of the first compressed rubber layer.

The ratio of the filler (particularly carbon black) may be, for example, about 10 to 100 parts by mass, preferably about 20 to 80 parts by mass with respect to 100 parts by mass of the rubber component. If the proportion of the filler is too small, the elastic modulus may be insufficient and the lateral pressure resistance and durability may be lowered, and if it is too large, the elastic modulus may be too high and the flexibility may be lowered.

The proportion of carbon black may be, for example, 50% by mass or more, preferably 90% by mass or more, or 100% by mass, based on the total amount of the filler. If the ratio of carbon black to the entire filler is too small, the rubber hardness of the first compressed rubber layer may decrease.

The crosslinked rubber composition forming the first compressed rubber layer may contain other additives, for example, the connecting reinforcing layer, if necessary, in addition to the rubber component, the filler, and the short fibers. It may contain other additives and the like exemplified in the section of article.

The ratio of the vulcanizing agent can be selected from the range of, for example, about 1 to 20 parts by mass with respect to 100 parts by mass of the rubber component in terms of solid content, depending on the type of the vulcanizing agent and the rubber component. For example, the ratio of the metal oxide as a vulcanizing agent is, for example, about 1 to 20 parts by mass, preferably about 3 to 17 parts by mass with respect to 100 parts by mass of the rubber component. When the metal oxide and the sulfur-based vulcanizer are combined, the ratio of the sulfur-based vulcanizer is, for example, about 0.1 to 50 parts by mass, preferably about 1 to 30 parts by mass with respect to 100 parts by mass of the metal oxide. Is. The ratio of the organic peroxide is, for example, about 1 to 8 parts by mass, preferably about 1.5 to 5 parts by mass with respect to 100 parts by mass of the rubber component.

Examples of the co-crosslinking agent (cross-linking aid or co-vulcanizing agent co-agent) include known cross-linking aids, for example, co-crosslinking agents exemplified as other additives of the cross-linked rubber composition in the connecting reinforcing layer. , Can be used alone or in combination of two or more. Among these cross-linking aids, polyfunctional (iso) cyanurate, polyfunctional (meth) acrylate, and bismaleimides (alene bismaleimide such as N, N'-m-phenylenedimaleimide or aromatic bismaleimide) are preferable. Bismaleimides are often used. By adding a cross-linking aid (for example, bismaleimides), the degree of cross-linking can be increased and adhesive wear can be prevented.

The ratio of the co-crosslinking agent (crosslinking aid) such as bismaleimides is, for example, about 0.1 to 10 parts by mass, preferably about 0.5 to 8 parts by mass with respect to 100 parts by mass of the rubber component in terms of solid content. Is.

The ratio of the vulcanization accelerator is, for example, about 0.1 to 15 parts by mass, preferably about 0.3 to 10 parts by mass with respect to 100 parts by mass of the rubber component in terms of solid content.

The ratio of the softener (oils such as naphthenic oil) is, for example, about 1 to 30 parts by mass, preferably about 3 to 20 parts by mass with respect to 100 parts by mass of the rubber component in terms of solid content.

The ratio of the processing agent or processing aid (such as stearic acid) is, for example, 10 parts by mass or less (for example, 0 to 10 parts by mass), preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the rubber component in terms of solid content. It is about a mass part.

The ratio of the adhesiveness improving agent (resorcin-formaldehyde cocondensate, hexamethoxymethylmelamine, etc.) is, for example, 0.1 to 20 parts by mass, preferably 0.3, based on 100 parts by mass of the rubber component in terms of solid content. It is about 5 parts by mass.

The ratio of the anti-aging agent is, for example, about 0.5 to 15 parts by mass, preferably about 1 to 10 parts by mass with respect to 100 parts by mass of the rubber component in terms of solid content.

(Second compressed rubber layer)
As the rubber component constituting the crosslinked rubber composition forming the second compressed rubber layer, the rubber component exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, including preferred embodiments. This is the same as the first compressed rubber layer.

The crosslinked rubber composition of the second compressed rubber layer may further contain a filler in addition to the rubber component. As the filler, the filler exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and the preferred embodiment and the ratio of carbon black in the filler are the same as those of the filler of the first compressed rubber layer. ..

In the second compressed rubber layer, the ratio of the filler (particularly carbon black) may be, for example, about 5 to 80 parts by mass, preferably about 10 to 60 parts by mass with respect to 100 parts by mass of the rubber component. If the proportion of the filler is too small, the elastic modulus may be insufficient and the lateral pressure resistance and durability may be lowered, and if it is too large, the elastic modulus may be too high and the flexibility may be lowered.

The vulcanized rubber composition of the second compressed rubber layer may further contain a plasticizer in addition to the rubber component. Examples of the plasticizer include the plasticizer exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer. These plasticizers can be used alone or in combination of two or more. Of these, ether ester-based plasticizers are preferable.

The ratio of the plasticizer is, for example, about 1 to 30 parts by mass, preferably about 3 to 20 parts by mass with respect to 100 parts by mass of the rubber component.

The crosslinked rubber composition of the second compressed rubber layer may further contain staple fibers and other additives in addition to the rubber component. As the short fibers, the short fibers exemplified as the short fibers of the first compressed rubber layer can be used, and as other additives, those exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer, etc. Additives are available. Of these, the second compressed rubber layer preferably contains a vulcanizing agent or a cross-linking agent, a vulcanization accelerator, a processing agent or a processing aid, and an antiaging agent in addition to the rubber component.

The ratio of the metal oxide as the vulcanizing agent is, for example, about 1 to 20 parts by mass, preferably about 3 to 17 parts by mass with respect to 100 parts by mass of the rubber component.

The ratio of the vulcanization accelerator is, for example, about 0.1 to 15 parts by mass, preferably about 0.3 to 10 parts by mass with respect to 100 parts by mass of the rubber component in terms of solid content.

The ratio of the processing agent or processing aid (such as stearic acid) is, for example, 10 parts by mass or less (for example, 0 to 5 parts by mass), preferably about 0.1 to 3 parts by mass, with respect to 100 parts by mass of the rubber component. ..

The ratio of the antiaging agent is, for example, 0.5 to 15 parts by mass, preferably about 1 to 10 parts by mass with respect to 100 parts by mass of the rubber component.

[Stretch layer (stretch rubber layer)]
The stretchable layer may be formed of a cloth (for example, the cloth exemplified for the protective layer) or the like, but a stretchable rubber layer is preferable. As described above, the rubber hardness of the stretched rubber layer is preferably higher than the rubber hardness of the second compressed rubber layer and less than or equal to the rubber hardness of the first compressed rubber layer.

The rubber hardness Hs of the stretched rubber layer can be selected from, for example, in the range of about 75 to 95 °, for example, 80 to 94 ° (for example, 83 to 93 °), preferably 86 to 92 °, and more preferably 87 to 91 ° (particularly). 89-91 °). If the rubber hardness is too small, the lateral pressure resistance may decrease, and if it is too large, the flexibility may decrease.

The tensile elastic modulus (modulus) of the stretched rubber layer is, for example, about 25 to 50 MPa, preferably 25 to 40 MPa, and more preferably 26 to 35 MPa (particularly 28 to 32 MPa) in the belt width direction. If the tensile modulus is too small, the lateral pressure resistance may decrease, and if it is too large, the flexibility may decrease.

The average thickness of the stretched rubber layer may be, for example, 0.5 to 10 mm (for example, 0.5 to 1.5 mm), preferably about 0.6 to 5 mm.

The stretchable rubber layer may be formed of a crosslinked rubber composition conventionally used as a rubber composition of a V-belt. The crosslinked rubber composition may be a crosslinked rubber composition containing a rubber component, and the rubber hardness of the stretched rubber layer can be adjusted by appropriately adjusting the composition of the composition. The method for adjusting the rubber hardness and the like is not particularly limited, and the composition and / or type of the components constituting the composition may be changed and adjusted, and from the viewpoint of convenience and the like, the ratio of the short fibers and the filler and / Alternatively, it is preferable to change the type for adjustment.

As the rubber component constituting the crosslinked rubber composition forming the stretchable rubber layer, the rubber component exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and a preferred embodiment is the first compressed rubber. Similar to the rubber component of the layer.

The vulcanized rubber composition of the stretched rubber layer may further contain staple fibers in addition to the rubber component. As the short fibers, the short fibers exemplified in the section of the first compressed rubber layer can be used, and the preferred embodiment and the ratio to the rubber component are the same as those of the first compressed rubber layer.

The vulcanized rubber composition of the stretched rubber layer may further contain a filler. As the filler, the filler exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and the preferred embodiment and the ratio of carbon black in the filler are the same as those of the filler of the first compressed rubber layer. ..

In the stretched rubber layer, the ratio of the filler (particularly carbon black) may be, for example, about 5 to 100 parts by mass, preferably about 10 to 80 parts by mass with respect to 100 parts by mass of the rubber component. If the proportion of the filler is too small, the elastic modulus may be insufficient and the lateral pressure resistance and durability may be lowered, and if it is too large, the elastic modulus may be too high and the flexibility may be lowered.

The crosslinked rubber composition of the stretchable rubber layer may further contain other additives in addition to the rubber component. As the other additive, other additives exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and the preferred embodiment and the ratio to the rubber component are the same as those of the first compressed rubber layer. be.

[Core layer (adhesive rubber layer)]
The core layer may include the core, and may be a core layer formed only of the core as described above. However, peeling between layers can be suppressed and belt durability can be improved. Therefore, it is preferable that the core body layer (adhesive rubber layer) is formed of the crosslinked rubber composition in which the core body is embedded. The core layer formed of the crosslinked rubber composition in which the core is embedded is usually referred to as an adhesive rubber layer, and the core is embedded in the layer formed of the crosslinked rubber composition containing a rubber component. There is. The adhesive rubber layer is interposed between the stretch rubber layer and the compressed rubber layer (particularly the first compressed rubber layer) to bond the stretch rubber layer and the compressed rubber layer, and a core body is embedded in the adhesive rubber layer. ing.

The average thickness of the adhesive rubber layer is, for example, 0.2 to 5 mm, preferably about 0.3 to 3 mm.

(Crosslinked rubber composition)
The rubber hardness Hs of the crosslinked rubber composition forming the adhesive rubber layer is, for example, 72 to 80 °, preferably 73 to 78 °, and more preferably about 75 to 77 °. If the rubber hardness is too small, the lateral pressure resistance may decrease, and if it is too large, the crosslinked rubber composition around the core becomes rigid and the core becomes difficult to bend, and the adhesive rubber layer generates heat. Deterioration (cracking), bending fatigue of the core body, etc. may occur, and the core body may peel off.

As the rubber component constituting the crosslinked rubber composition forming the adhesive rubber layer, the rubber component exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and a preferred embodiment is the first compressed rubber. Similar to the rubber component of the layer.

The crosslinked rubber composition of the adhesive rubber layer may further contain a filler in addition to the rubber component. As the filler, the filler exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and the preferred embodiment and the ratio of carbon black in the filler are the same as those of the first compressed rubber layer.

In the adhesive rubber layer, the ratio of the filler may be, for example, about 1 to 100 parts by mass, preferably about 10 to 80 parts by mass with respect to 100 parts by mass of the rubber component. The ratio of carbon black may be, for example, about 1 to 50 parts by mass, preferably about 10 to 45 parts by mass with respect to 100 parts by mass of the rubber component.

The crosslinked rubber composition of the adhesive rubber layer may further contain a plasticizer in addition to the rubber component. As the plasticizer, the plasticizer exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and the preferred embodiment and the ratio to the rubber component are the same as those of the plasticizer of the second compressed rubber layer. ..

The vulcanized rubber composition of the adhesive rubber layer may further contain staple fibers and other additives in addition to the rubber component. As the short fibers, the short fibers exemplified in the section of the first compressed rubber layer can be used, and as other additives, the additives exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer. Can be used. Of these, the adhesive rubber layer preferably contains a vulcanization agent or a cross-linking agent, a vulcanization accelerator, a processing agent or a processing aid, and an antiaging agent in addition to the rubber component. The ratio of these additives to the rubber component is the same as that of the second compressed rubber layer.

(Core body)
The core body included in the core body layer is usually a core wire (twisted cord) arranged at predetermined intervals in the belt width direction. The core wires are arranged so as to extend in the length direction of the belt, and are usually arranged so as to extend in parallel at a predetermined pitch parallel to the length direction of the belt. When the core body is embedded in the adhesive rubber layer, it is sufficient that a part of the core body is embedded in the adhesive rubber layer, and the core wire is embedded in the adhesive rubber layer from the viewpoint of improving durability (core wire). The form in which the entire surface is completely embedded in the adhesive rubber layer) is preferable. As the core body, a core wire is preferable.

Examples of the fiber constituting the core wire include the fiber exemplified as the material of the first filamentous body, and can be used alone or in combination of two or more. Among these fibers, polyester fibers (particularly polyethylene terephthalate fibers and polyethylene naphthalate fibers) and polyamide fibers (particularly aramid fibers) are preferable from the viewpoint of high modulus.

The thread constituting the core wire may be a multifilament thread. The fineness of the multifilament yarn may be, for example, about 2000 to 10000 dtex (particularly 4000 to 8000 dtex). The multifilament yarn may contain, for example, about 100 to 5000 filaments, and preferably may contain about 500 to 4000 filaments.

As the core wire, a twisted cord using a multifilament yarn (for example, various twists, one twist, rung twist, etc.) can be usually used. The average wire diameter (diameter of the twisted cord) of the core wire may be, for example, 0.5 to 3 mm, preferably about 0.6 to 2.5 mm.

When the core wire is embedded in the adhesive rubber layer, a conventional adhesive treatment (surface treatment) [for example, a fiber structure of a connecting reinforcing layer] is used in order to improve the adhesiveness with the crosslinked rubber composition forming the adhesive rubber layer. The treatment exemplified as the body adhesion treatment] may be performed. The adhesion treatment may be performed alone or in combination of two or more, or may be sequentially treated with the same or different surface treatment agents a plurality of times. The core wire is preferably bonded with at least an RFL solution.

[Outer cloth]
The outer cover cloth (cover cloth) is made of a conventional cloth. Examples of the fabric include the fabrics exemplified in the section of the protective layer, among these, woven fabrics such as plain weave, twill weave, and Akiko weave, and woven fabrics having an intersection angle of more than 90 ° and about 120 ° or less. Woven fabrics such as knitted fabrics are preferable, and are widely used as cover fabrics for transmission belts for general industrial use and agricultural machinery. Woven cloth (wide angle cloth)] is particularly preferable. Further, in applications where durability is required, a wide-angle canvas may be used.

The composition of the fabric, that is, the type and fineness of the fibers constituting the fabric, the basis weight, the average thickness, the thread density, and the like are the same, including the examples and preferred embodiments of the section of the protective layer.

The outer cover may be a single layer or a multi-layer (for example, 2 to 5 layers, preferably about 2 to 4 layers), but from the viewpoint of productivity and the like, it may be a single layer (1 ply) or 2 layers. A layer (2 plies) is preferred.

The outer cover cloth may be a cloth to which a rubber component is attached in order to improve the adhesiveness with the belt body. The outer cloth to which the rubber component is attached is a cloth that has been subjected to an adhesive treatment such as a treatment of soaking (immersing) a rubber glue in which a rubber composition is dissolved in a solvent, or a treatment of friction (rubbing) of a solid rubber composition. May be. The bonding treatment may be performed by treating at least one surface of the fabric, and it is preferable to treat at least the surface in contact with the belt body.

As the rubber component constituting the rubber composition to be adhered to the outer cover, the rubber component exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and a preferred embodiment is the first compressed rubber layer. It is the same as the rubber component.

The rubber composition to be adhered to the outer cover cloth may further contain a filler in addition to the rubber component. As the filler, the filler exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and the preferred embodiment and the ratio of carbon black in the filler are the same as those of the filler of the first compressed rubber layer. ..

In the rubber composition to be adhered to the outer cover, the ratio of the filler (particularly carbon black) is, for example, about 5 to 80 parts by mass, preferably about 10 to 75 parts by mass with respect to 100 parts by mass of the rubber component.

The rubber composition to be adhered to the outer cover may further contain a plasticizer in addition to the rubber component. As the plasticizer, the plasticizer exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer can be used, and the preferred embodiment is the same as the plasticizer of the second compressed rubber layer.

In the rubber composition to be adhered to the outer cover, the proportion of the plasticizer is, for example, about 3 to 50 parts by mass, preferably about 5 to 40 parts by mass with respect to 100 parts by mass of the rubber component.

The rubber composition adhered to the outer cover may further contain staple fibers and other additives in addition to the rubber component. As the short fibers, the short fibers exemplified in the section of the first compressed rubber layer can be used, and as other additives, the addition exemplified in the section of the crosslinked rubber composition which may be contained in the connecting reinforcing layer. Agents are available. Of these, the rubber composition to be adhered to the outer cover preferably contains a vulcanization agent or a cross-linking agent, a vulcanization accelerator, a processing agent or a processing aid, and an antiaging agent in addition to the rubber component. The ratio of these additives to the rubber component is the same as that of the second compressed rubber layer.

The coefficient of friction of the outer cover, which is the transmission surface, is, for example, 0.9 to 1, preferably 0.91 to 0.96, and more preferably 0.92 to 0.95. In the present application, the coefficient of friction can be measured by the method described in Examples described later.

The average thickness of the outer cover (in the case of multiple layers, the average thickness of each layer) is, for example, about 0.4 to 2 mm, preferably about 0.5 to 1.4 mm. If the thickness of the outer cover is too thin, the wear resistance may be lowered, and if it is too thick, the flexibility of the belt may be lowered.

[Reinforcing cloth layer]
If necessary, each V-belt portion is placed on the inner peripheral surface (inner peripheral side surface) of the compressed rubber layer [when the V-belt portion is a wrapped V-belt, the inside of the compressed rubber layer is as shown in FIG. Between the peripheral surface and the outer cover] may further include a reinforcing cloth layer, and may or may not include the reinforcing cloth layer.

The reinforcing cloth layer is formed of a conventional cloth as in the case of the outer cloth. As the woven fabric, the woven fabric exemplified in the section of the protective layer can be used, and the preferred embodiment is the same as that of the protective layer and the outer cover.

The reinforcing cloth layer may be a cloth to which a rubber component is attached in order to improve the adhesiveness with the compressed rubber layer and the outer cover cloth. The cloth to which the rubber component is attached is, for example, a cloth that has been subjected to an adhesive treatment such as a treatment of soaking (immersing) a rubber glue in which a rubber composition is dissolved in a solvent, or a treatment of friction (rubbing) a solid rubber composition. There may be. As the rubber composition, the rubber composition exemplified as the rubber composition of the outer cover can be used, and the preferred embodiment is the same as that of the outer cover. The adhesive treatment may be performed by treating at least one surface of the fabric, preferably at least the surface in contact with the compressed rubber layer, and particularly preferably both sides.

The average thickness of the reinforcing cloth layer is, for example, 0.4 to 2 mm, preferably about 0.5 to 1.4 mm. If the thickness of the reinforcing cloth layer is too thin, the effect of improving the wear resistance may be reduced, and if it is too thick, the flexibility of the belt may be reduced.

[Manufacturing method of bonded V-belt]
The bonded V-belt of the present invention is obtained through a step of manufacturing an uncrosslinked V-belt portion (belt main body portion) by a conventional method and then connecting a plurality of obtained uncrosslinked V-belt portions with a tie band. Be done.

First, as a typical method for producing an uncrosslinked tie band (tie band precursor), a fiber structure bonded by using an uncrosslinked holding rubber sheet for a connecting reinforcing layer obtained by rolling treatment is used. An uncrosslinked connecting reinforcing layer precursor is prepared by laminating on both sides of the above, and if necessary, the uncrosslinked protective layer cloth is further laminated on one surface of the connecting reinforcing layer precursor. Tie band can be prepared. At the time of laminating, the directions of the fibers constituting the fiber structure (first thread-like body) in the connecting reinforcing layer precursor and the cloth for the protective layer may be adjusted respectively. Further, the connecting reinforcing layer precursor may be used as the tie band precursor without laminating the protective layer fabric.

Further, as a method for manufacturing the uncrosslinked V-belt portion, for example, it can be manufactured by the method described in JP-A-6-137381 and WO2015 / 104778 pamphlet. Specific examples of the method for manufacturing the uncrosslinked wrapped V-belt portion include an adhesive-treated reinforcing cloth, an uncrosslinked second compressed rubber layer sheet and a first compressed rubber layer sheet obtained by rolling. After cutting the laminate and setting it in the mantle, the uncrosslinked adhesive rubber layer sheet is wound on the first compressed rubber layer sheet, and then the core body is wound on the wound adhesive rubber layer sheet. Further, a winding step of winding an uncrosslinked stretch rubber layer sheet on the wound core, a cutting step of cutting (ring-cutting) the obtained annular laminate on the mantle, and a pair of pulleys for the cut annular laminate. The uncrosslinked wrapped V-belt is subjected to a skiving process in which the rubber is cut into a V shape while being rotated, and a cover winding process is performed in which the obtained uncrosslinked rubber body is covered with an outer cover precursor. You can get a part.

The above is an example of a method for manufacturing an uncrosslinked wrapped V-belt portion, but the fabric for reinforcing cloth is not always necessary, and the compressed rubber layer may be one layer or three or more layers. When the V-belt portion is a low-edge V-belt or a low-edge cogged V-belt, it can be manufactured by a conventional manufacturing method of these V-belts. For example, when the V-belt portion is a low-edge V-belt, it may be manufactured in the same manner as described above in the method for manufacturing the uncrosslinked wrapped V-belt portion, except that the cover winding process of covering with the outer cloth precursor is not performed. When the V-belt portion is a low-edge cogged V-belt, a cog portion may be provided on the inner peripheral surface side of the compressed rubber layer sheet (if necessary, a laminate with the reinforcing cloth) by a mold or the like.

A typical process of connecting a plurality of uncrosslinked V-belt portions with a tie band will be described with reference to FIG. A plurality of uncrosslinked V-belt portions V1 are fitted into a groove portion having an inverted trapezoidal cross section formed in a cylindrical or annular lower cross-linking mold 21, and then a tie band T is set on the radially outer portion thereof. Will be done. In the tie band set, the tie band T is wound along the circumferential direction around a plurality of uncrosslinked wrapped V-belt portions V1 arranged in the width direction, and a plurality of uncrosslinked wrapped V-belt portions V1. The tie band T is set against the above. At this time, the tie band T is set so that the first filamentous body forming the fiber structure in the connecting reinforcing layer precursor extends in the belt width direction. The tie band T set in this way and a plurality of uncrosslinked V-belt portions V1 are sandwiched between the upper cross-linking mold 22 and the lower cross-linking mold 21 and cross-linked while being pressurized. It is used for (vulcanization process). By this cross-linking step (vulcanization step), a cross-linked sleeve in which a plurality of wrapped V-belt portions V1 are connected by a tie band T is formed. The crosslinked sleeve thus formed is cut to a predetermined width to form a coupled V-belt having a predetermined number of V-belt portions.

In the crosslinking step, the crosslinking temperature can be selected according to the type of rubber component, and is, for example, about 120 to 200 ° C, preferably about 150 to 180 ° C. The sheets for each rubber layer containing the staple fibers can be arranged (oriented) in the rolling direction by a method of rolling with a calendar roll or the like.

The protective layer, the connecting reinforcing layer, and the V-belt portion are bonded to each other by a rubber component (rubber composition) and / or an adhesive component on their surfaces (joining interface). For example, as a tie band precursor, a protective layer precursor formed of a cloth subjected to a friction (rubbing) treatment of a solid rubber composition and an uncrosslinked holding rubber for a connecting reinforcing layer obtained by rolling treatment. When a laminate with an uncrosslinked connecting reinforcing layer precursor in which a fiber structure is embedded (or sandwiched) in a sheet is used, the friction rubber composition and the sandwiching rubber composition for the connecting reinforcing layer are crosslinked with the protective layer. The connecting reinforcing layers are bonded to each other. Similarly, in the step of setting the tie band precursor to the uncrosslinked V-belt portion, a plurality of uncrosslinked V-belt portions are mutually connected via the tie band precursor (connecting reinforcing layer precursor) as the connecting portion. Includes an uncrosslinked belt binding step to bond. In this step, for example, the connecting reinforcing layer and the V-belt portion are brought together by the reaction between the sandwiching rubber composition for the connecting reinforcing layer on the peripheral side of the tie band precursor body and the rubber composition on the outer peripheral side of the uncrosslinked V-belt portion. Be combined. The form of the outer peripheral side of the uncrosslinked V-belt portion may be appropriately selected according to the V-belt portion as long as it can be bonded to the tie band precursor (connecting reinforcing layer precursor). For example, the rubber composition is subjected to friction treatment. It may be an outer coat precursor or an stretched layer formed of a stretched cloth or the like, or it may be an uncrosslinked rubber sheet for a stretched rubber layer or the like. The uncrosslinked belt coupling step is not limited to this method, and the connecting reinforcing layer precursor may be wound alone, and the uncrosslinked rubber is further placed on the connected reinforcing layer precursor wound alone (outer peripheral side). A tie band precursor may be formed by winding a protective layer precursor formed of a sheet.

In the coupled V-belt of the present invention, the number of V-belt portions is not limited to the three in FIG. 1, and may be two or more, for example, 2 to 10, preferably 2 to 8, and more preferably 2. ~ 6 pieces. The adjacent V-belt portions may be arranged in parallel in the longitudinal direction, and are not limited to the mode in which they are arranged at intervals as shown in FIG. 1, and may be arranged without intervals. From the viewpoint of productivity and the like, it is preferable to arrange the adjacent wrapped V-belt portions at intervals. The distance between the adjacent V-belts is, for example, 1.7 to 4.3 mm, preferably 2 to 4.1 mm, and more preferably 2.3 to 3.9 mm. The tie band is not limited to the mode in which each V-belt portion can be connected by contacting and integrating with the entire outer peripheral surface of each V-belt portion as shown in FIG. 1, and the outer peripheral surface of the V-belt portion is not limited. May have a region that does not come into contact with the tie band. From the viewpoint of belt durability, it is preferable that the entire outer peripheral surface of each V-belt portion is in contact with the tie band and integrated.

Since the coupled V-belt of the present invention is suitable for high-load applications, it is suitable for machines with high horsepower, and the load (reference transmission capacity) applied to one V-belt portion may be 10 PS or more. It may be preferably 20 PS or more, more preferably 22 PS or more (for example, about 22 to 30 PS).

Further, when the coupled V-belt is a wrapped coupled V-belt, it is preferable to use it in a layout with a high load and a long span (long distance between axes) such as a large-scale agricultural machine. Since the coupled V-belt is suitable for a long span layout, the maximum span length (distance between the axes of the pulley and the pulley) may be 1000 mm or more, for example, about 2000 to 5000 mm.

The total length of the bonded V-belt may be, for example, 200 inches (508 cm) or more, for example, 220 to 500 inches, or 30 to 200 inches.

The width of the outer peripheral surface of the belt of each V-belt portion may be, for example, 15 to 35 mm (particularly 16 to 25 mm), and the thickness of each V-belt portion may be, for example, 10 to 20 mm (particularly 10 to 15 mm). good.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. The raw materials for the rubber composition, the method for preparing the rubber composition, the fiber material used, the method for measuring or evaluating each physical property, and the like are shown below.

[Raw material for rubber composition]
Chloroprene rubber: "PM-40" manufactured by DENKA Co., Ltd.
Magnesium oxide: "Kyowa Mag 30" manufactured by Kyowa Chemical Industry Co., Ltd.
Stearic acid: "Stearic acid camellia" manufactured by NOF CORPORATION
Anti-aging agent: "Non-flex OD-3" manufactured by Seiko Kagaku Co., Ltd.
Carbon Black: "Seast 3" manufactured by Tokai Carbon Co., Ltd.
Silica: Evonik Japan Co., Ltd., "ULTRASIL (registered trademark) VN3", BET specific surface area 175 m ² / g
Plasticizer: "RS-700" manufactured by ADEKA CORPORATION
Vulcanization accelerator (or cross-linking accelerator): "Noxeller TT" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.
Zinc oxide: "Zinc oxide 3 types" manufactured by Shodo Chemical Industry Co., Ltd.
Naphthenic oil: "NS-900" manufactured by Idemitsu Kosan Co., Ltd.
N, N'-m-Fenirange Maleimide: "Balknock PM" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.
Aramid short fiber: "Conex short fiber" manufactured by Teijin Corporation, average fiber length 3 mm, average fiber diameter 14 μm, RFL solution (2.6 parts of resorcin, 1.4 parts of 37% formalin, vinylpyridine-styrene-butadiene) Short fiber with a solid content adhesion rate of 6% by mass, which has been bonded with polymer latex (17.2 parts manufactured by Nippon Zeon Co., Ltd., 78.8 parts water).

[Core line]
Aramid fiber twisted cord, average wire diameter 1.985 mm.

[Adhesive rubber layer, friction rubber, rubber composition for holding rubber of fiber structure]
The rubber compositions A or C having the formulations shown in Table 1 are kneaded with a Banbury mixer, and the kneaded rubber is passed through a calendar roll to form an uncrosslinked rolled rubber sheet having a predetermined thickness, which is a sheet for an adhesive rubber layer and a rubber for holding a fiber structure. Sheet (sheet for connecting reinforcing layer) was produced. Further, the rubber composition B shown in Table 1 was rubber-kneaded with a Banbury mixer to prepare a lumpy uncrosslinked rubber composition for friction. Table 1 also shows the results of measuring the hardness and tensile elastic modulus of the crosslinked product of each rubber composition.

[Rubber Composition for First Compressed Rubber Layer, Second Compressed Rubber Layer and Stretched Rubber Layer]
The rubber compositions D to E having the formulations shown in Tables 2 and 3 are kneaded with a Banbury mixer, and the kneaded rubber is passed through a calendar roll to form an uncrosslinked rolled rubber sheet having a predetermined thickness. 2 A sheet for a compressed rubber layer and a sheet for an stretchable rubber layer were prepared, respectively. The results of measuring the hardness and tensile elastic modulus of the crosslinked product of each rubber composition are also shown in Tables 2 and 3.

[Rubber hardness Hs of crosslinked rubber]
Each rubber layer sheet was press-crosslinked at a temperature of 160 ° C. and a time of 30 minutes to prepare a crosslinked rubber sheet (100 mm × 100 mm × 2 mm thickness). Using a laminate of three crosslinked rubber sheets as a sample, the hardness was measured using a durometer A type hardness tester according to JIS K6253 (2012). For the lumpy uncrosslinked rubber composition B for friction, a test piece was sampled from the lumpy rubber and passed through a calendar roll to prepare an uncrosslinked rolled rubber sheet having a predetermined thickness.

[Tension modulus of crosslinked rubber (modulus)]
Using the crosslinked rubber sheet prepared for measuring the rubber hardness Hs of the crosslinked rubber as a sample, a test piece punched into a dumbbell shape (No. 5 type) was prepared according to JIS K6251 (2017). In the sample containing the staple fibers, the samples were punched out in a dumbbell shape so that the arrangement direction (columnar direction) of the staple fibers was the tensile direction. Then, both ends of the test piece were grasped by chucks (grabbers), and when the test piece was pulled at a speed of 500 mm / min, the tensile stress (tensile elastic modulus) until the test piece was cut was measured.

[Reinforcing cloth layer, outer cover cloth and woven cloth for protective layer]
Woven fabric of a blended yarn of polyester fiber and cotton (polyester fiber / cotton = 50/50 mass ratio) (120 ° wide angle weave, fineness of 20th warp and 20th weft, warp and weft density 75 / Using the rubber composition B in Table 1, the rubber composition B and the woven fabric are simultaneously passed between rolls having different surface speeds of the calendar rolls (50 mm, grain amount 280 g / m ² , average thickness 0.50 mm). , Friction treatment (performed once for each of the front and back of the woven fabric) by rubbing the rubber composition B between the weaves of the woven fabric to prepare the reinforcing cloth precursor, the outer coat precursor and the protective layer precursor. did.

[Preparation of uncrosslinked wrapped V-belt]
After cutting and placing a laminate of the reinforcing cloth precursor, the sheet for the second compressed rubber layer shown in Table 3, and the sheet for the first compressed rubber layer shown in Table 2 on the outer peripheral surface of the cylindrical drum. , The adhesive rubber layer sheet, the core wire, and the stretch rubber layer sheet shown in Table 2 are sequentially laminated and attached, and the reinforcing cloth precursor, the uncrosslinked rubber layer, and the core wire are laminated in a tubular shape. A cross-linked sleeve was formed. The obtained uncrosslinked sleeve was cut in the circumferential direction in a state of being arranged on the outer periphery of the cylindrical drum to form an annular uncrosslinked rubber belt. In the first compressed rubber layer and the stretchable rubber layer containing the staple fibers, the staple fibers were arranged in the belt width direction. Further, the sheets for each rubber layer are provided so that the stretched rubber layer thickness, the first compressed rubber layer thickness L2 and the compressed rubber layer thickness L1 (all of which are the thicknesses after cross-linking) in the bonded V-belt have the average thickness shown in Table 4. The thickness was adjusted.

Next, the uncrosslinked rubber belt was removed from the drum, and both side surfaces of the uncrosslinked rubber belt were cut (skipped) at a predetermined angle to form a cross-sectional shape of the uncrosslinked rubber belt into a V-shaped cross section. As shown in FIG. 2, an uncrosslinked rubber belt having a V-shaped cross section (stretch rubber layer 14, adhesive rubber layer 16 in which a core body (core wire) 15 is embedded, first compressed rubber layer 17a, second compressed rubber layer 17b). , The belt made of the reinforcing cloth layer 19) was subjected to a cover winding treatment in which the periphery thereof was covered with the outer cover 18 precursor to form an uncrosslinked wrapped V-belt portion.

[Example 1]
(Preparation of Linked Reinforcing Layer Precursor 1)
Fibrous structure having the structure shown in Table 5 (net for connecting reinforcing layer) [Kurabo Co., Ltd. "Clenette (registered trademark)" (warp and weft: PET multifilament yarn (non-twisted yarn), structure: in FIG. 1 As shown, a TRT structure in which warps are arranged alternately above and below the warps, contacts of the warps and wefts: bonded with a resin), which has been bonded with chloroprene latex] on both sides of the rubber composition C in Table 1. The formed fiber structure sandwiching rubber sheets were laminated, passed through a roll, and crimped to prepare a connecting reinforcing layer precursor 1 in which the net was sandwiched between the sandwiching rubbers.

(Preparation of bonded V-belt)
After fitting the obtained six uncrosslinked wrapped V-belt portions into the annular groove portion formed in the lower cross-linking mold, the connecting reinforcing layer precursor 1 and the connecting reinforcing layer precursor 1 are formed on the radially outer portion thereof. The protective layer precursor laminated on the connecting reinforcing layer precursor 1 was set as a tie band precursor. That is, in the set of tie band precursors, the connecting reinforcing layer precursor 1 and the protective layer precursor are provided along the circumferential direction (belt length direction) of the six uncrosslinked wrapped V-belts arranged in the width direction. The tie band precursor was set on the six uncrosslinked wrapped V-belts, which were wound in order. In the connecting reinforcing layer precursor 1, the warp threads of the connecting reinforcing layer net shown in Table 5 are substantially parallel to the belt length direction, and the weft threads (first filamentous body) are substantially parallel to the belt width direction. Arranged. Further, in the protective layer precursor laminated on the connecting reinforcing layer precursor 1, the direction of the yarn constituting the woven fabric is oblique with respect to the belt width direction (both the warp and the weft are 30 with respect to the belt width direction, respectively). °, that is, both threads are symmetrical with respect to the belt length direction).

The tie band precursor and the six uncrosslinked wrapped V-belts set in this way are sandwiched between the upper cross-linking mold and the lower cross-linking mold and pressurized to 1.2 MPa, and the cross-linking temperature is 160 ° C. Six wrapped V-belts (RMA B type, cross-sectional dimensions: width 16.5 mm x thickness 11 mm, belt length 71 inches, average thickness of outer cover 1.2 mm) are connected by a tie band. A bonded crosslinked belt was obtained. The obtained crosslinked belt was cut to produce a coupled V-belt having three wrapped V-belt portions (wrapped coupled V-belt).

The wrapped coupling belt obtained in Example 1 was cut into three wrapped V-belts, and the coefficient of friction of the wrapped V-belt alone was measured by the method described later and found to be 0.93.

[Examples 2 to 6 and Reference Examples 1 to 2]
(Preparation of connecting reinforcing layer precursors 2 to 8)
The connecting reinforcing layer precursors 2 to 8 were prepared in the same manner as in Example 1 except that the fibrous structure (net for connecting reinforcing layer) in the connecting reinforcing layer precursor 1 was changed as shown in Table 5. ..

(Preparation of bonded V-belt)
Bonded V-belts (wrapped coupling having three wrapped V-belt portions) in the same manner as in Example 1 except that the obtained connecting reinforcing layer precursors 2 to 8 were used instead of the connecting reinforcing layer precursor 1. V-belt) was prepared.

[Comparative Example 1]
(Preparation of Linked Reinforcing Layer Precursor 9)
The woven fabric for the protective layer was used instead of the fibrous structure (net for the connecting reinforcing layer) in the connecting reinforcing layer precursor 1. That is, a woven fabric of a blended yarn of polyester fiber and cotton (polyester fiber / cotton = 50/50 mass ratio) (120 ° wide angle weave, fineness of 20th warp and 20th weft, warp and weft density 75). A sheet for holding a fiber structure holding rubber formed of the rubber composition C in Table 1 is laminated on both sides of a book / 50 mm, a grain amount of 280 g / m ² , and an average thickness of 0.50 mm), and the woven fabric is held by the holding rubber. A connecting reinforcing layer precursor 9 sandwiched between the two was prepared.

(Preparation of bonded V-belt)
Instead of the connecting reinforcing layer precursor 1 of the first embodiment, the connecting reinforcing layer precursor 9 is used, and the direction of the threads constituting the woven fabric in the connecting reinforcing layer precursor 9 is the same as that of the protective layer precursor. That is, except that they are arranged so as to be diagonal to the belt width direction (both warp and weft are 30 ° with respect to the belt width direction, that is, both threads are symmetrical with respect to the belt length direction). Manufactured a coupled V-belt having three wrapped V-belt portions in the same manner as in Example 1.

[Belt friction coefficient]
As shown in FIG. 4, the coefficient of friction of the belt is such that one end of the cut belt 31 is fixed to the load cell 32, a load 33 of 3 kgf is placed on the other end, and the winding angle of the belt around the pulley 34 is adjusted. The belt 31 was wound around the pulley 34 at 45 °. Then, the belt 31 on the load cell 32 side was pulled at a speed of 30 mm / sec for about 15 seconds, and the average friction coefficient of the friction transmission surface was measured. At the time of measurement, the pulley 34 was fixed so as not to rotate.

[Running test]
Using a tester with a two-axis layout consisting of a drive pulley and a driven pulley, the time until a crack was generated in the ring break or the coupling member was compared. As shown in FIG. 5, the drive pulley and the driven pulley used a pulley having a narrower groove width in the center than usual. When such a pulley is used, the central V-belt portion protrudes in the outer peripheral direction when it is hung on the pulley, so that a strong tensile force acts on the tie band (coupling member) in the belt width direction. The outer diameter (diameter) of the drive pulley and the driven pulley was 146 mm, the rotation speed of the drive pulley was 1750 rpm, the load of the driven pulley was 22.5 kW, the shaft load was 300 kgf, and the test temperature (atmospheric temperature) was 25 ° C.

Table 5 shows the results of running evaluation of the obtained wrapped coupled V-belt.

In Table 5, the warp and weft (first thread-like body) and warp and warp (second thread-like body) thread densities and gaps (shortest distance between adjacent threads) are all average values. Further, the thickness of the fiber structure, the thickness of the connecting reinforcing layer and the thickness of the protective layer are all average thicknesses.

As is clear from the results in Table 5, Comparative Example 1 in which the threads were arranged diagonally crossed with respect to the belt width direction (the fiber structure does not have the first thread-like body) was measured in 90 hours in the running test. A ring break occurred. On the other hand, in Example 1 in which the yarn (warp and weft) was arranged in the belt width direction (the fiber structure has the first filamentous body), a crack was confirmed in the tie band (bonding member) after 500 hours, but the ring was formed. No break occurred.

In Examples 2 to 3, the warp and weft (first thread-like body) and warp threads (second thread-like body) of Example 1 have a large thread density [or a small thread gap, or a cover factor (CF). This is an example of [larger]. In Example 2, the ring breakage did not occur even after 500 hours had passed as in Example 1, whereas in Example 3, the ring breakage occurred in 384 hours, and the durability was slightly lowered (however, it was acceptable). Was within range). It is presumed that this result is because the density of the yarn is too high [or the gap between the yarns is too small or the CF is too large], so that cracks (or defects) are easily propagated.

Example 4 and Reference Example 1 are examples in which the density of the yarn is smaller than that of Example 1 [or the gap between the yarns is larger or the CF is smaller], contrary to Examples 2 and 3. In Example 4, ring breakage occurred in 312 hours, and the durability was slightly lower than that in Example 1, but it was within the permissible range. In Reference Example 1, in which the yarn density was further reduced as compared with Example 4, ring breakage occurred in a relatively short time (120 hours), and the durability was low. Therefore, if the density of the yarn is too small [or the gap between the yarns is too large or the CF is too small], the strength (or rigidity) of the connecting reinforcing layer is reduced even though the effect of suppressing the propagation of cracks is high. It is considered that a sufficient reinforcing effect cannot be obtained.

Reference Example 1 was an example in which the densities of both the weft and warp yarns were changed to be smaller [or the gap between the yarns was larger or the CF was smaller] than in Example 1, whereas Example 5 and Example 1 were changed. Reference example 2 is an example in which only one of the threads is changed. In Example 5 in which only the warp was changed [the weft (first filament) is the same as in Example 1], ring breakage did not occur even after 500 hours had elapsed as in Example 1. On the other hand, in Reference Example 2 in which only the weft was changed [the warp (second filament) is the same as in Example 1], the ring breakage occurred in 96 hours, and the durability was greatly reduced. From this, the aspect of the warp (second filament) does not have much influence on the suppression of ring breakage, and it is important to adjust the density [or the gap or CF] of the weft (first filament). It turned out.

In Example 6, the material of the fiber structure was changed from PET to aramid, but as in Example 1, no ring breakage occurred even after 500 hours had passed.

Among Examples 1 to 2 and 5 to 6 in which the ring breakage did not occur even after the lapse of 500 hours, in Example 5 in which the warps were arranged in a slightly sparse state, the shape of the fiber structure was formed when the bonding belt was manufactured. Since it is easily broken and the handleability is slightly inferior, Examples 1 to 2 and 6 are preferable, and Example 1 is particularly preferable from the viewpoint of moldability and productivity.

The combined V-belt of the present invention can be used for general industrial machines such as compressors, generators and pumps, and agricultural machines such as combiners, rice transplanters and mowing machines, and can effectively suppress ring breakage in a high load environment. It can be suitably used for high-load machines used. High-load machines include, for example, large agricultural machines used in Europe and the United States (for example, tillers, vegetable transplanters, transplanters, binders, combines, vegetable harvesters, grain removers, bean cutters, corn harvesters, horse bells). Examples include high-load machines used in high-load, long-span layouts such as harvesters (harvesters, beet harvesters, etc.).

T ... Tie band (joining member)
1 ... Connecting reinforcement layer 2 ... Fiber structure (net, net-like structure)
2a ... First thread-like body (warp and weft)
2b ... Second filament (warp)
3 ... Protective layer V, V1 ... V belt part 4, 14 ... Stretch layer (stretch rubber layer)
5,15 ... Core body (core wire)
6, 16 ... Core layer (adhesive rubber layer)
7 ... Compressed rubber layer 8,18 ... Outer cloth (cover cloth)
10 ... Bonded V-belt 17a ... First compression rubber layer 17b ... Second compression rubber layer 19 ... Reinforcing cloth layer

Claims (10)

Includes a plurality of V-belts arranged in the belt width direction and a tie band for connecting the outer peripheral surfaces of the plurality of V-belts; each V-belt includes a core layer including a core and the core. A bonded V-belt including an stretch layer laminated on the outer peripheral side of the belt of the body layer and a compressed rubber layer laminated on the inner peripheral side of the belt of the core body layer.
The tie band has a connecting reinforcing layer containing a fibrous structure; the fibrous structure comprises a plurality of first filaments extending at least in the belt width direction; the first filaments are belt length. Arranged at least spaced in the direction,
A bonded V-belt in which the first filaments adjacent to each other are arranged with a gap of 0.5 to 7.5 mm in the belt length direction. The bonded V-belt according to claim 1, wherein the density of the first filament is 5 to 50 lines / 50 mm, and the fineness of the first filament is 100 to 1000 dtex. The coupled V-belt according to claim 1 or 2, wherein the cover factor of the first filament is 150 to 1200 (lines / 50 mm) × (dtex) ^1/2 . The bond V according to any one of claims 1 to 3, wherein the connecting reinforcing layer further contains a rubber component; the rubber component is interposed between the first filaments adjacent to each other in the belt length direction. belt. The bond V according to any one of claims 1 to 4, wherein the first filament is a non-twisted yarn having a twist number of 1 time / less than 100 mm or a sweet twisted yarn having a twist number of 1 to 29 times / 100 mm. belt. The first filament contains synthetic fibers and / or inorganic fibers, and the synthetic fibers include at least one synthetic fiber selected from polypropylene-based fibers, polyvinyl alcohol-based fibers, polyester-based fibers and polyamide-based fibers. The coupled V-belt according to any one of claims 1 to 5. One of claims 1 to 6, wherein the fiber structure is a net including a plurality of second filaments extending in a direction intersecting the belt width direction and at least connected to the first filaments. The combined V-belt according to. The bonded V-belt according to any one of claims 1 to 7, wherein the tie band is laminated on the outer peripheral side of the connecting reinforcing layer and further has a protective layer including a cloth. The method according to any one of claims 1 to 8, wherein the outer peripheral surfaces of a plurality of V-belts arranged in the belt width direction are connected to a tie band having the connecting reinforcing layer. A method for suppressing ring breakage of the obtained coupled V-belt by connecting a plurality of V-belt portions with the tie band according to any one of claims 1 to 8.

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