JP2000291743A - Transmission belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission belt having excellent abrasion resistance of aramid fiber and excellent durability in a reinforcing cloth used for a power transmission belt and required to have elasticity. A plurality of blocks (8, 8, ...) are locked and fixed at a predetermined pitch and at a predetermined interval in a belt length direction on a pair of endless tension bands (1, 1) on both sides.
In the belt, each tension band 1 is embedded in a shape-retaining rubber 2, and is buried in the shape-retaining rubber 2 at a predetermined pitch and a predetermined interval in the width direction of the tension band 1, and has a length of the tension band 1. , An upper reinforcing cloth 4 covering the upper surface of the shape-retaining rubber 2, and a lower reinforcing cloth 5 covering the lower surface of the shape-retaining rubber 2. At least one of the upper reinforcing cloth 4 and the lower reinforcing cloth 5 is a stretchable cloth made of only aromatic polyamide fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission belt provided with a reinforcing cloth subjected to an adhesive treatment on a belt surface. The technical field of the high load transmission V-belt used in a belt transmission such as a belt-type continuously variable transmission in a general-purpose agricultural machine or an automobile has a reinforcing cloth on an upper surface or a lower surface of a tension band.

[0002]

2. Description of the Related Art In recent years, belt type continuously variable transmissions have been developed as transmissions for agricultural machines such as combines and tractors, automobiles, and the like, from the viewpoint of improving operability during shifting and improving fuel consumption rate. Is underway. As a high-load transmission V-belt used in this type of transmission, for example, one described in Japanese Patent Application Laid-Open No. 60-49151 is known.

In this device, a large number of blocks are locked and fixed at a predetermined pitch and at a predetermined interval in a belt length direction in a pair of endless tension bands on both sides, as shown in FIG. On the upper and lower surfaces of each of the tension bands A, a number of upper surface grooves a and lower surface grooves b provided so as to extend in the belt width direction are respectively provided in the belt length direction (the left-right direction in the figure).
Are arranged at predetermined pitches and at predetermined intervals.
On both sides of each of the blocks B, a slit-shaped fitting portion c penetrating in the belt length direction is provided so as to extend in the belt width direction, and an upper edge d of the fitting portion c is provided.
Are engaged with the upper surface groove a of each of the tension bands A, and the lower edge portion e is engaged with the lower surface groove b.
Are locked and fixed to both tension bands A, A. And FIG.
As exemplified in the above, each of the tension bands A has a shape retaining layer f,
A core wire g is buried in the shape-retaining layer f so as to extend in the belt length direction, and upper and lower surfaces of the shape-retaining layer f are covered with an upper reinforcing cloth k and a lower reinforcing cloth i, respectively, as reinforcing cloth. ,
Thus, high load transmission can be endured.

That is, in the traveling of the V-belt,
When the belt B is wound around the pulley and bends along the groove of the pulley, each block B is fixed by both tension bands A, A so as not to swing in a plane perpendicular to the belt width direction, so that high load transmission is achieved. Making it possible.

At this time, the upper reinforcing cloth k applies the force F ₁ of each block B to swing to the upper edge d of the fitting portion c.
Will be received repeatedly. Furthermore, the upper reinforcing fabric k is bent along the groove of the pulley, when leaving from the pulley, receive the pressing force F ₂ from said upper edge d.

The fixing of each block B by each tension band A is mainly performed by the lower surface groove b. That is, since the lower reinforcing cloth i suppresses the deformation of the shape retaining layer f, the shape retaining action of each tension band A is enhanced, and each block B can be fixed so as not to swing each block B. In other words, in order to obtain a fixing force F ₃ required for each block B will be joining the compressive force F ₄ of equality amounts to the lower surface groove b of each tension band A.

A plain weave, a twill weave, and a satin weave which have been stretched in the longitudinal direction of the tension band so as to form the upper groove a and the lower groove b of the tension band with high precision as the upper reinforcing cloth k and the lower reinforcing cloth i. Nylon reinforced cloth is used.

[0008]

However, as described above, the upper reinforcing cloth k and the lower reinforcing cloth i are used under severe conditions, and when the V-belt is used under a higher load, The conventional nylon reinforced cloth cannot sufficiently cope with wear resistance, strength and the like.

In such a case, it is conceivable to use a woven fabric of aromatic polyamide fibers (hereinafter referred to as "aramid fibers") having excellent abrasion resistance and high strength properties as a reinforcing cloth. Since the fiber cannot be stretched like a fiber, the reinforcing cloth is given elasticity by using a woven fabric in which a yarn in which an elastic yarn such as a urethane fiber is covered with an aramid fiber is a yarn extending in the longitudinal direction of the tension band.

However, in the above-described reinforcing cloth using aramid fiber, the elastic yarn such as urethane fiber is broken at an early stage by the running of the belt and falls off from the woven fabric, and the aramid fiber is free from being adhered to the rubber layer. As a result, the filaments of the aramid fibers are subjected to not only friction but also torsion and bending deformation. However, since aramid fibers exhibit extremely weak properties against these deformations, the reinforcing cloth using the above-mentioned aramid fibers breaks down quickly without exhibiting the excellent wear resistance of the aramid fibers. Will be done.

The present invention has been made in view of the above points, and an object of the present invention is to provide a reinforcing cloth used for a power transmission belt to exhibit the excellent abrasion resistance of aramid fiber and improve durability. It is to obtain an excellent transmission belt.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention uses an elastic fabric made of only aramid fiber as a reinforcing fabric for a belt.

[0013] Specifically, the invention of claim 1 is a power transmission belt provided with a reinforcing cloth subjected to an adhesive treatment on a belt surface, wherein the reinforcing cloth is a stretchable cloth made of only aromatic polyamide fibers. It is a transmission belt.

In the above configuration, the reinforcing cloth is made of only aramid fiber, and the entire aramid fiber is fixed to the belt body. Therefore, the elastic yarn is damaged by the belt running and falls off from the woven fabric, as in the case of using a reinforcing cloth in which the elastic yarn is covered with aramid fiber and the woven fabric is provided with elasticity. The fiber is in a free state, and there is no possibility that the filament of the aramid fiber is subjected to deformation such as twisting or bending due to contact with a pulley or the like and is not broken. Therefore, the excellent wear resistance of the aramid fiber as the reinforcing cloth for the power transmission belt can be exhibited, and the durability of the power transmission belt can be improved.

Further, since the aramid fiber reinforcing cloth has elasticity, even if a complicated surface shape exists in the length direction or width direction of the power transmission belt, the surface is covered with the reinforcing cloth and the precision is improved. Can form its shape well,
Its surface can be reinforced with aramid fibers having high strength properties.

According to a second aspect of the present invention, in the transmission belt according to the first aspect, the stretchable fabric is a knit.

In the above structure, the knitted fabric forms the fabric by connecting the loops formed by the yarns in the vertical and horizontal directions. And since the yarn which forms the loop has a bend, the knitted fabric has elasticity. Therefore,
2. The method according to claim 1, wherein the reinforcing cloth of the transmission belt is made of a knit.
The operation of the described invention will be specifically carried out.

According to a third aspect of the present invention, there is provided an endless tension band in which a number of locking portions corresponding to the upper and lower surfaces are provided at predetermined pitches and at predetermined intervals in the belt length direction. An upper surface of the tension band, comprising: a plurality of blocks having an engagement portion that engages with the locking portion, the blocks being fixed to the tension band at predetermined pitches and at predetermined intervals in the belt length direction. And a high-load transmission V-belt having a lower surface covered with a reinforcing cloth by an adhesive treatment, wherein at least one of the upper-side reinforcing cloth and the lower-side reinforcing cloth of the tension band is the length of the tension band. A high-load transmission V-belt, characterized in that the V-belt is a stretchable fabric made of only an aromatic polyamide fiber that stretches in the vertical direction.

With the above configuration, when a reinforcing cloth made of only aramid fiber is used as the upper reinforcing cloth, the entire aramid fiber is fixed to the upper surface of the tension band. Therefore, the elastic yarn is damaged by the belt running and falls off from the woven fabric, as in the case of using an upper reinforcing cloth that imparts elasticity to the woven fabric using a yarn obtained by covering the elastic yarn with aramid fiber,
The aramid fiber is in a free state, and the filament of the aramid fiber is not broken by twisting or bending deformation due to the force of the block to swing or the pressing force received from the block. Therefore, the excellent abrasion resistance of the aramid fiber as the upper reinforcing cloth of the tension band can be exhibited, and the durability of the high load transmission V-belt can be improved.

Similarly, when a reinforcing cloth made of only aramid fiber is used for the lower reinforcing cloth, the entire aramid fiber is fixed to the lower surface of the tension band. Therefore, the aramid fiber is in a free state, and the filament of the aramid fiber is not subjected to twisting or bending deformation due to the action of the compressive force from the block and is not broken. Therefore, the excellent abrasion resistance of the aramid fiber as the lower reinforcing cloth of the tension band can be exhibited, and the durability of the V belt for high load transmission can be improved.

Further, since the aramid fiber reinforcing cloth has elasticity in the length direction of the tension band, the upper surface or the lower surface of the tension band is covered with the reinforcing cloth and the shape of the upper surface groove or the lower surface groove is accurately formed. The upper surface or the lower surface of the tension band can be reinforced by aramid fiber having high strength properties.

According to a fourth aspect of the present invention, there is provided the V-belt for high load transmission according to the third aspect, wherein the stretchable fabric is a knitted fabric.

In the above construction, the knitted fabric forms the fabric by connecting the loops formed by the yarns in the vertical and horizontal directions. And since the thread which comprises a loop has a bend, a knitted fabric will have elasticity. Therefore,
By using the upper reinforcing cloth or the lower reinforcing cloth of the tension band as a knit, the operation of the invention according to claim 3 can be specifically performed.

[0024]

As described above, according to the first and second aspects of the present invention, the reinforcing cloth is made of only aramid fiber, and the entire aramid fiber is fixed to the belt body. Therefore, the aramid fiber is in a free state, and there is no possibility that the filament of the aramid fiber is broken by twisting or bending deformation. Therefore, the excellent wear resistance of the aramid fiber as the reinforcing cloth of the power transmission belt can be exhibited, and the durability of the power transmission belt can be improved. In addition, since the aramid fiber reinforcing cloth has elasticity, even if there is a complicated surface shape in the length or width direction of the power transmission belt, the surface is covered with the reinforcing cloth and the shape is accurately adjusted. It can be formed and its surface can be reinforced by aramid fibers with high strength properties.

According to the third and fourth aspects of the present invention, when a reinforcing cloth made of only aramid fiber is used as the upper reinforcing cloth, the entire aramid fiber is fixed to the surface of the tension band. . Therefore, the aramid fiber is in a free state, and there is no possibility that the filament is broken by twisting or bending deformation. Therefore, the excellent abrasion resistance of the aramid fiber as the upper reinforcing cloth of the tension band can be exhibited, and the durability of the V-belt for high load transmission can be improved. Similarly, when a reinforcing cloth made of only aramid fiber is used for the lower reinforcing cloth, the entire aramid fiber is fixed to the surface of the tension band. Therefore, there is no possibility that the aramid fiber is in a free state and is broken by twisting or bending deformation of the filament. Therefore, the excellent abrasion resistance of the aramid fiber as the lower reinforcing cloth of the tension band can be exhibited, and the durability of the V belt for high load transmission can be improved. Further, since the reinforcing cloth of aramid fiber has elasticity in the length direction of the tension band, it is possible to form the shape of the upper surface groove or the lower surface groove accurately while covering the upper surface or the lower surface of the tension band with the reinforcing cloth. The upper or lower surface of the tension band can be reinforced with aramid fiber having high strength properties.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 shows a V-belt A for high load transmission according to Embodiment 1 of the present invention. Although not shown, the V-belt A is used when constructing a belt-type continuously variable transmission that is wound around two drive pulleys on the driving side and the driven side, each of which includes a fixed sheave and a movable sheave. A large number of blocks 8, 8,... Are locked and fixed at a predetermined pitch and at a predetermined interval in the belt length direction on a pair of endless tension bands 1, 1 on both sides.

Each of the tension bands 1 is embedded in a shape-retaining rubber 2, and is buried in the shape-retaining rubber 2 at a predetermined pitch and at a predetermined interval in the width direction of the tension band 1. ., An upper reinforcing cloth 4 covering the upper surface of the shape-retaining rubber 2, and a lower reinforcing cloth 5 covering the lower surface of the shape-retaining rubber 2.

The shape-retaining rubber 2 is made of a rubber composition containing hydrogenated nitrile rubber (H-NBR) as a main component, and the cord 3 is made of resorcinol-formalin latex (R).
FL) A braided cord made of aramid fiber that has been subjected to an adhesive treatment with a solution.

The upper reinforcing cloth 4 is a flat knitted fabric made of only aramid fiber (trade name: Tecnora, Technora). The stitch structure has a wale density of 65 sh.
ot / 5cm, and course density is 56 shot / 5c
m. The thickness of the yarn used is 2 in cotton count.
It is 0th.

In the bonding treatment of the upper reinforcing cloth 4, a soaking treatment of a rubber paste containing hydrogenated nitrile rubber (H-NBR) as a main component is performed. The surface corresponding to the surface of the tension band is coated with a rubber paste obtained by adding carbon fiber to the rubber paste. By providing the coating layer on the surface of the upper reinforcing cloth 4 in this manner, the force of each block 8 to swing is effectively dispersed, and the upper reinforcing cloth 4 is less likely to be worn.

The lower reinforcing cloth 5 is a woven fabric having the same structure as the upper reinforcing cloth 5.

The bonding treatment of the lower reinforcing cloth 5 is carried out by immersing the resin in a resorcinol-formalin latex (RFL) solution in which the latex component is hydrogenated nitrile rubber (H-NBR) and heating it, and treating the hydrogenated nitrile rubber (H-NBR) NBR) as a main component is soaked with a rubber paste. In addition, processing with rubber glue is performed only soaking processing,
No coating treatment is performed. When the surface corresponding to the tension band surface side of the lower reinforcing cloth 5 is coated with rubber glue,
This is because the coating layer serves as a cushion, and when the lower reinforcing cloth 5 receives a compressive force from each block 8, the compressive force is absorbed and the tension conversion rate of the belt decreases.

On the upper surface of each tension band 1, a number of upper surface grooves 6, 6,...
On the lower surface, a plurality of lower grooves 7, 7,... Each having an arc-shaped cross section corresponding to the upper grooves 6, 6,. Further, they are provided so as to extend in the belt width direction at predetermined intervals. In addition, the upper surface groove 6 and the lower surface groove 7 are formed by press-fitting rubber together with a reinforcing cloth into a mold provided with a ridge corresponding to each groove shape on the surface. At this time,
Since the upper reinforcing cloth 4 and the lower reinforcing cloth 5 extend in the longitudinal direction of the tension band 1, the shapes of the upper surface groove 6 and the lower surface groove 7 are formed with high precision.

On the other hand, each of the blocks 8 has a substantially inverted trapezoidal plate shape, and both side surfaces thereof are slidable contact portions 9 and 9 which slidably contact the groove surface of the speed change pulley. On both sides of each block 8, slit-shaped fitting portions 10, 10 penetrating in the belt length direction and extending in the belt width direction are provided in a state opened to the side. I have. The upper edge portion of each fitting portion 10 has a convex cross section projecting downward, and is formed as a downward protruding ridge 11 as an engaging portion that engages with the upper surface groove 6 of the tension band 1. ing. The lower edge of each of the fitting portions 10 has an arc-shaped cross section that protrudes upward, and has an upwardly projecting ridge 12 as an engaging portion that engages with the lower surface groove 7 of the tension band 1. Have been.

Next, the operation and effect will be described.

In the V belt A, a reinforcing cloth made of only aramid fiber is used for the upper reinforcing cloth 4, and the entire aramid fiber is fixed to the upper surface of the tension band 1. Therefore, the elastic yarn is damaged by the belt running and falls off from the woven fabric, as in the case of using a reinforcing cloth in which the elastic yarn is covered with aramid fiber and the woven fabric is provided with elasticity. There is no possibility that the filaments of the aramid fiber are twisted or bent and broken by the action of the force of the block 8 swinging or the pressing force received from the block 8 due to the free state of the fiber. Similarly, in the V-belt A, the lower reinforcing cloth 5 is made of a knitted fabric made of only aramid fiber, and the entire aramid fiber is fixed to the lower surface of the tension band 1. Accordingly, the aramid fiber is in a free state, and the filament of the aramid fiber is not broken by twisting or bending deformation by the action of the compressive force from the block 8. Therefore, the abrasion resistance of the aramid fiber as the upper reinforcing cloth 4 and the lower reinforcing cloth 5 of the tension band 1 can be exhibited, and the V-belt A has excellent durability even under the use condition of higher load than before. It will be.

Further, since the aramid fiber reinforcing cloth has elasticity in the length direction of the tension band 1, the shapes of the upper surface groove 6 and the lower surface groove 7 can be formed accurately while covering the upper surface and the lower surface of the tension band. The upper and lower surfaces of the tension band are reinforced by aramid fibers having high strength properties.

<Examples> -Examples- The V belt A according to the first embodiment was used as an example.

Comparative Example 1 An aramid fiber woven fabric obtained by imparting elasticity to a woven fabric using a yarn obtained by covering a urethane elastic yarn with an aramid fiber (trade name of Teijin Corp .: Technora) is used as the upper and lower reinforcing fabric and is woven. A V-belt P having the same configuration as the V-belt A was prepared except that the direction in which the cloth had elasticity was used as the length direction of the tension band. The woven structure of the reinforcing cloth is a 2/2 twill weave. The yarn extending in the length direction of the tension band is a covering yarn obtained by winding aramid fiber (trade name: Tecnora, Inc., Technora) of 200 de around 420 de spandex, and the yarn density is 100 yarns / 5 cm. And the yarn extending in the width direction of the tension band is cotton count 20.
It is a count of aramid fiber (trade name of Teijin Corp .: Technora), and the yarn density is 70 yarns / 5 cm.

Comparative Example 2 Nylon fiber woven fabric obtained by imparting elasticity to a woven fabric using wooly-processed nylon (nylon 6.6) fiber yarns was used as an upper and lower reinforcing fabric, and the elasticity of the woven fabric was measured. A V-belt Q having the same configuration as that of the V-belt A except that the direction of the tension belt was used for the length direction of the tension belt was prepared. The woven structure of the reinforcing cloth is a 2/2 twill weave. The thread extending in the length direction of the tension band is a 210 de wooly-processed nylon fiber, and the thread density is 10%.
It is 0 / 5cm. The yarn extending in the width direction of the tension band is a 210-de nylon fiber, and the yarn density is 100%.
Book / 5 cm.

-Running Test- A running test was performed on each of the V belts A, P, and Q. That is, as shown in FIG.
Is wound between a drive pulley 22 having a pulley diameter of 120 mm and a driven pulley 23 having a pulley diameter of 60 mm, and a tension DW (DW = 150 kg) is applied to the drive pulley 22 to apply tension to the V belt 23. The drive pulley 22 is moved to the driven pulley 21 without applying a load to the driven pulley 22 at 6000r.
The V-belt 23 was rotated at a speed of pm, and the degree of wear of the upper and lower reinforcing cloths of each V-belt 23 at the time when 500 hours had elapsed was examined.
The ambient temperature was set at 90 ° C.

Table 1 shows the results of the running test.

[0044]

[Table 1]

As can be seen from the description in Table 1, the V-belt A according to the example has better wear resistance than the V-belt P according to the comparative example 1. Here, Example and Comparative Example 1 are common in that aramid fibers are used as upper and lower reinforcing cloths. However, in the example, while the constituent materials are all aramid fibers,
Comparative Example 1 is different in that a yarn in which a urethane elastic yarn is covered with an aramid fiber is used as a yarn extending in the length direction of the tension band of the woven fabric as a constituent material. In other words, the reason why Comparative Example 1 is inferior in abrasion resistance to that of Example is that the urethane elastic yarn breaks down early and falls off the woven fabric due to the belt running, the aramid fiber filaments are in a free state, and the aramid fiber filaments are The reason for this is that the block is subjected to deformation such as torsion or bending by the action of the compressive force or the like exerted by the block and is broken. Therefore, it was confirmed that the excellent abrasion resistance of the aramid fiber can be exhibited by using all the constituent materials of the upper and lower reinforcing cloths with the aramid fiber.

The V-belt A according to the embodiment is the same as that of the comparative example 2.
Is superior in wear resistance to the V-belt Q according to the above. Here, in the example, the constituent materials of the upper and lower reinforcing cloths are all aramid fibers, whereas in the comparative example 2, they are nylon fibers. Therefore,
It was confirmed that the fiber properties of aramid fiber, which is superior in abrasion resistance to nylon fiber, were reflected in the belt performance.

The V-belt Q according to Comparative Example 2 has better wear resistance than the V-belt P according to Comparative Example 1. That is, in Comparative Example 1, although aramid fibers are used as constituent materials of the upper and lower reinforcing cloths, the wear resistance is inferior to Comparative Example 2 in which nylon fibers are used. This is comparative example 1.
However, the urethane elastic yarn breaks down early due to the belt running and falls off the woven fabric, the aramid fiber is in a free state, and the aramid fiber filament is subjected to deformation such as twisting or bending by the action of the compressive force exerted by the block. This is because, without demonstrating the excellent abrasion resistance of the aramid fiber, it will be destroyed at an early stage.

(Embodiment 2) FIG. 3 shows a toothed belt B according to an embodiment of the present invention. The toothed belt B includes tooth rubber 31 arranged at equal pitches inside the belt, back rubber 32 outside the belt, a core wire 33 embedded in the belt longitudinal direction,
It comprises a tooth cloth 31 and a reinforcing cloth 34 covering the tooth bottom 32.

Here, a rubber compound mainly composed of hydrogenated nitrile rubber (H-NBR) is used as the tooth rubber 31 and the back rubber 32. Further, as the core wire 33, a glass core wire subjected to an adhesive treatment by RFL is used.
The reinforcing cloth 34 is a flat knitted knit made of only aramid fiber and has been subjected to an adhesive treatment with RFL and rubber glue. The knitted reinforcing cloth 34 composed of only aramid fiber has a wale density of 65 sho.
t / 5 cm, and course density is 56 shot / 5 cm
And the belt length direction is the direction of the course. The yarn used is cotton count 20.
It is count.

Next, the operation and effect will be described.

In the toothed belt B, the reinforcing cloth 34 is made of only aramid fiber, and the entire aramid fiber is fixed to the tooth rubber surface and the bottom layer of the toothed belt B. Therefore, the elastic yarn is damaged by the belt running and falls off from the woven fabric, as in the case of using a reinforcing cloth in which the elastic yarn is covered with aramid fiber and the woven fabric is provided with elasticity. The fiber is in a free state, and there is no possibility that the filament of the aramid fiber is subjected to deformation such as twisting or bending due to contact with a pulley or the like and is not broken. Therefore,
The excellent wear resistance of the aramid fiber as the reinforcing cloth 34 can be exhibited, and the toothed belt B has excellent durability.

Since the aramid fiber reinforcing cloth 34 has elasticity, the tooth shape is formed with high accuracy while covering the belt surface, and the belt surface is reinforced by the aramid fiber reinforcing cloth to cause chipping or the like. Is prevented.

(Other Embodiments) In Embodiments 1 and 2, para-aramid fibers are used as aramid fibers. However, the present invention is not limited to this, and meta-aramid fibers may be used. .

Further, in Embodiments 1 and 2, the knitting structure is a flat knitting which is a weft knitting, but is not particularly limited thereto, and may be a rubber knitting, a pearl knitting, or other variable knitting. Alternatively, it may be a warp knit. In addition, it is preferable that the direction in which the knitted material is rich in expansion and contraction, such as the direction of a rubber knitting course, be taken in the length direction of the tension belt or the toothed belt. As a result, the groove shape of the tension band or the tooth shape of the toothed belt is accurately formed. When the surface of a transmission belt having a complicated shape in the belt width direction, such as a poly V-ribbed belt, is covered with a reinforcing cloth, it is desirable that the direction in which the knitted fabric is expanded and contracted is set in the belt width direction.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a part of a high-load transmission V-belt according to a first embodiment of the present invention.

FIG. 2 is a schematic view showing a procedure of a durability test of a high-load transmission V-belt.

FIG. 3 is a perspective view showing a part of a toothed belt B according to Embodiment 2 of the present invention.

FIG. 4 is a side view showing a state of a block force applied to a lower surface groove of the tension band.

FIG. 5 is a side view showing a configuration of a conventional tension band.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 tension band 2 shape-retaining rubber 3 core wire 4 upper reinforcing cloth 5 lower reinforcing cloth 6 upper groove 7 lower groove 8 block 9 sliding contact part 10 fitting part 11 downward protrusion 12 upward protrusion 21 driven pulley 22 drive pulley 23 V Belt 31 Tooth rubber part 32 Back rubber part 33 Core wire 34 Reinforcement cloth a Upper surface groove b Lower surface groove c Fitting part d Upper edge e Lower edge f f Shape-retaining layer g Core i Lower reinforcement cloth k Upper reinforcement cloth

Claims (4)

[Claims] 1. A power transmission belt provided with an adhesive-treated reinforcing cloth on a belt surface, wherein the reinforcing cloth is a stretchable cloth made of only aromatic polyamide fibers. 2. The transmission belt according to claim 1, wherein the elastic fabric is a knit. 3. An endless tension band provided on the upper and lower surfaces with a plurality of locking portions corresponding to the upper and lower sides at a predetermined pitch and a predetermined interval in the belt length direction. A plurality of blocks having an engaging portion that engages with each other and fixedly fixed to the tension band at a predetermined pitch and at a predetermined interval in the belt length direction, and reinforcing the upper surface and the lower surface of the tension band. A high-load transmission V-belt in which a cloth is coated by an adhesive treatment, wherein at least one of the reinforcing cloth on the upper surface and the reinforcing cloth on the lower surface of the tension band expands and contracts in the length direction of the tension band. A high-load transmission V-belt, which is a stretchable fabric made of only aromatic polyamide fibers. 4. The high-load transmission V-belt according to claim 3, wherein the stretchable cloth is a knit.
belt.