JP2957314B2 - Industrial belt - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an industrial belt,
In particular, the present invention relates to improvement of a reinforcing member (tensile member) embedded in a belt body.

[0002]

2. Description of the Related Art Conventionally, industrial belts such as transmission belts such as toothed belts, V-belts, flat belts and ribbed belts and transport belts have high strength, high elastic modulus, high dimensional stability and high dimensional stability. Since properties such as adhesiveness are required, a reinforcing cord made of fiber and a reinforcing body such as a cloth-like material are embedded in the belt body to satisfy these properties. As the reinforcing member, a twisted yarn obtained by twisting a plurality of yarns is generally used, and the type thereof can be classified into a twisted yarn, a single twisted yarn, a Lang twisted yarn, and the like according to a twisting method. At present, among the above-mentioned twisted yarns, variously twisted yarns are most frequently used for the reinforcing member of the industrial belt.

However, in the industrial belt in which the reinforcing body is formed by the twisted yarn, a portion where the monofilaments come into strong contact with each other at a deep angle occurs in the twisted yarn. There is a problem that the strength is reduced and the bending fatigue resistance is deteriorated.

Therefore, as an industrial belt improved in the above-mentioned problem (bending fatigue resistance), a belt made of a single-twisted yarn or a lang-twisted yarn has been proposed (JP-A-59-19744). reference).

[0005]

However, as described above, in the industrial belt in which the reinforcing member is constituted by the single twist yarn or the Lang twist yarn, stretching and dipping are performed in comparison with the structure in which the reinforcing member is constituted by the twist yarn. Later, the tensile modulus tends to decrease, and the dimensional stability tends to decrease.

[0006] Further, since the single twist yarn and the Lang twist yarn are twisted in only one direction, the untwisted yarn and the twisted yarn are liable to be untwisted and to be easily frayed at the ends, and are difficult to be processed. There is also a problem that fraying is likely to occur on the surface.

Furthermore, in the case of an industrial belt using a single-twisted yarn or a rung-yarn as a reinforcing body, the single-twisted yarn or the like has a twisting direction as described above. There is also a problem that uneven wear easily occurs. On the other hand, as disclosed in, for example, JP-A-56-103008, by using an alternate arrangement of S-twisted and Z-twisted single-twisted yarns as a reinforcing body,
Conveyor belts that eliminate uneven wear have been proposed. However, in this case, since two cords (single twisted yarn) are arranged in a belt in parallel and spirally,
There are a total of four cord cut surfaces on the left and right belt end faces, which lowers the belt strength maintenance rate and is difficult to adopt.

[0008] By the way, braids have been used since ancient times. Of these braids, the round braid has the property of being particularly superior in bending fatigue resistance due to its structural characteristics, and is also better in terms of dimensional stability than twisted yarn, so it is used for industrial applications. It is preferable to use it as a reinforcing member for a belt because both physical properties such as bending fatigue resistance and dimensional stability can be improved.

In addition, in the case where the round braid is used as a reinforcing member of an industrial belt, twisting the driven yarn constituting the round braid improves the aligned state of the driven yarn. The strength of the braid is improved, and the life of the industrial belt can be extended. And, at this time, if the twisting direction of the left-turned driving yarn and the right-turning driving yarn of the round-dried braid are made the same, the round-braided braid may have directionality, and thus the directionality is generated. In the case of an industrial belt using a round braided braid as a reinforcing body, there may be cases where it is not sufficiently satisfactory in terms of bending fatigue resistance. It is necessary to orient.

[0010] Unless the braiding angle (braid angle) of the driving thread of the round braid is set to an appropriate value, sufficient bending fatigue properties cannot be obtained. That is, when the braid angle is large, the alignment becomes poor, while when the braid angle is large, the wear between the filaments becomes large.

Further, if the number of the driving yarns is not appropriate, the strength per sectional area is not high.

It has also been found that an ideal cord can be obtained in terms of bending fatigue resistance and dimensional stability by introducing a core thread having an appropriate thickness into the center portion of a round braid.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to construct a reinforcing body by using an ancient round braid instead of a twisted yarn, and to improve the number of twists of a driven yarn, An object of the present invention is to provide an industrial belt which has sufficient bending fatigue resistance and dimensional stability and has a long service life by appropriately setting the direction, the braid angle, the number of fibers to be driven, and the thickness of the core yarn.

[0014]

In order to achieve the above object, a first solution of the present invention is to provide an industrial belt in which a reinforcing member made of fiber is buried in a belt main body, wherein the reinforcing member is made of four to four. A round braid having a hollow portion formed into a cylindrical shape by an even number of eight yarns, and a core thread provided in the hollow portion of the round braid. Further, the twist coefficient K of the yarn constituting the round braid is set to 194 ± 155 in the following equation.

[0015]

(Equation 2)

T: the number of twists per 10 cm D: the number of deniers Further, the round braid is composed of a right-turning yarn and a left-turning yarn in which the twisting direction is set to be opposite to the S twist and the Z twist. .
Furthermore, the braid angle of the round braid is set to 15 ° ± 5 °.

According to a second aspect of the present invention, in the first aspect, the round braid is formed by cylindrically braiding four round braids, and the round braid comprises a round braid. The ratio of the denier number of the core yarn to the denier number of 2.5 to 7.
That is, it is set to 5%.

According to a third aspect of the present invention, in the first aspect, the round braid is formed by cylindrically braiding the six braids, and the round braid is formed. The ratio of the denier number of the core yarn to the denier number is 7.5 to 2
That is, it was set to 4.0%.

According to a fourth aspect of the present invention, in the first aspect, the round braid is formed by cylindrically braiding with eight threads, and the round braid is formed. The ratio of the denier number of the core yarn to the denier number of
That is, it is set to 3.0%.

[0020]

According to the present invention according to the first to fourth aspects of the present invention, the reinforcing member made of fibers embedded in the belt body is
A rounded braid having a hollow portion cylindrically braided with 4 to 8 even-numbered yarns, and a core thread provided at the center of the rounded braid; Is 194 ± 155 in the following equation.
Is set to

[0021]

(Equation 3)

T: the number of twists per 10 cm D: the number of deniers The above-mentioned round braid is composed of a right-turning yarn and a left-turning yarn in which the twist direction is set to be opposite to S twist or Z twist. In addition, the braid angle of the round braid is set to 15 ° ± 5 °. In addition, the ratio of the denier number of the core yarn to the denier number of the yarns forming the round braid is 2.5 to 2.5 when the round braid is braided with four yarns.
7.5%, if braided with 6 yarns, 7.
When it is braided with eight yarns, it is set to 14.0 to 43.0%, respectively.

As a result, a uniform stress is applied to the monofilament constituting the yarn as a structural characteristic of the round braid, and the directionality of the driven yarn is not canceled out by the S twist and the Z twist. The abrasion resistance between them is reduced, and the bending fatigue resistance is greatly improved.

[0024] Further, the yarns can be aligned well by the appropriate number of twists of the driving yarn, the perfect circular shape can be maintained by the core yarn having an appropriate thickness, and the dimensional stability can be improved.
Further, by setting the number of the driven yarns to 4 to 8, the strength per cross-sectional area is increased.

[0025]

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

FIG. 3 shows a toothed belt A as an industrial belt according to an embodiment of the present invention. The toothed belt A has a back rubber layer 1, a reinforcing member 2 made of fibers embedded in the back rubber layer 1, and one side (lower side in FIG. 3) of the back rubber layer 1 having the same shape as the back rubber layer 1. A belt body 4 comprising a tooth rubber layer 3 integrally formed of rubber material is provided, and a tooth cloth 5 is integrally attached to the surface of the tooth rubber layer 3 of the belt body 4. Have been.

As a feature of the present invention, the reinforcing member 2 has an even number of 4 to 8 (four in this embodiment) as shown in FIG. 1 and FIG. With a plurality of round braids 7, 7,... Having a hollow portion 8 assembled in a cylindrical shape at 6,..., And a core thread 9 inserted and arranged in the central portion 8 of each round braid 7. The yarn 6 constituting the round braid 7 has a twist coefficient K set to 194 ± 155 in the following equation.

[0028]

(Equation 4)

T: the number of twists per 10 cm D: the number of deniers The thread 6 constituting the round braid 7 is a rightward thread in which the twist direction is set to be opposite to the S twist and the Z twist. And a transflective yarn, and the braid angle of the round braid 7 is set to 15 ° ± 5 °. In addition, the ratio of the denier number of the core thread 9 to the denier number of the yarn 6 constituting the round braid 7 is 2.5 to 2.5 when the round braid 7 is braided with four yarns 6. 7.5%, 7.5 to 24.0% when braided with six yarns 6, 14.0 to braid with eight yarns 6. 43.0%
Are set respectively.

As the type of the yarn 6, inorganic fibers, organic fibers, metal fibers and the like are used, and further, any of spun yarns composed of long fibers and short fibers or mixed yarns thereof may be used. In short, it may be appropriately selected according to the required performance of the toothed belt A. The number of threads 6 constituting the round braid 7 is not limited as long as it is an even number of 4 or more and 8 or less. The reason why the number of drivings is set to an even number of 4 or more and 8 or less in order to not decrease the strength per cross-sectional area, as shown in the data of FIG. 4, when the number of drivings exceeds 8 This is because the strength drops sharply. Also, it is necessary to form a symmetrical cylindrical hollow portion 8 inside the braid. The data in FIG. 4 uses Kevlar 29 (trade name, manufactured by DuPont) 1500 de as the driving yarn 6,
This is a value obtained without inserting the core thread 9. Furthermore, the total denier number, monofilament denier number, and the like of the yarn 6 may be appropriately selected according to the required performance of the toothed belt A. As the type of the core yarn 9, a fiber of the same type or different material and composition as the yarn 6 is used according to the use and purpose.

Further, the twist coefficient K of the yarn 6 constituting the round braid 7 is set to 194 ± 155 based on the data shown in FIG. In other words, the data in FIG. 5 uses four-stroke Kevlar 29 (trade name, manufactured by DuPont) as the driving yarn 6, and sets the twisting direction to S-turning yarn and S-twisting to right-turning yarn. And when the braid angle is 20 °, the number of twists of the leftward and rightward yarns is 0 to 20 respectively.
It is a value obtained by changing the amount in the range of times / 10 cm. As is clear from this data, the belt strength retention rate changed with the number of twists peaking at 5/10 cm, and an excellent belt strength retention rate was obtained when the number of twists was 5 ± 4 times / 10 cm.
This value corresponds to a twist coefficient K = 194 ± 155.

Further, the braid angle of the round braid 7 is set at 15 ° ±
The setting of 5 ° is based on the data in FIG. In other words, the data of FIG. 6 uses four-stroke Kevlar 29 (trade name, manufactured by DuPont) as the driving yarn 6 and has a twisting direction of 5 times / cm with S-twist on the reversing yarn, and the right direction. The value is obtained by varying the braid angle to 5 to 30 ° when the translucent yarn is wound 5 times / cm each with Z twist and the core yarn 9 is made of Tetron 300de. As is clear from this data, the braid angle is 10
At 20 °, an excellent belt strength retention rate was obtained.

Further, the ratio of the denier number of the core thread 9 to the denier number of the yarns 6 constituting the round braid 7 is set to 2 when the round braid 7 is braided with four yarns 6. .
13. When the yarn is braided with six yarns 6, the ratio is 7.5 to 24.0%. When the yarn is braided with eight yarns 6, 14. The setting of 0 to 43.0% is based on the data of FIG. That is, the data of FIG.
(Dupont Co., Ltd.) Use 1500 hits with 4 shots,
When the braid angle is set to 5 to 30 ° and the twist direction is 5 times / cm for S-twisting on the left-turning yarn and 5 times / cm for Z-twisting on the right-turning yarn, This is a value obtained by varying the denier number of the yarn 9 in the range of 0 to 1000 de. As is apparent from this data, when the denier number of the core yarn 9 is 150 to 450 de, an excellent belt strength retention rate was obtained. In this case, the ratio of the denier of the core thread 9 to the denier of the driving thread 6 is 2.5 to 2.5%.
7.5%. Similarly, in the case of the braided braid 7 having six driving yarns 6, the denier of the core yarn 9 is 700 to 2200d.
In the case of e, an excellent belt strength retention rate was obtained. At this time, the ratio of the denier number of the core yarn 9 to the denier number of the driven yarn 6 was 7.5 to 24.0%. Further, in the case of the braided braid 7 having eight driving yarns 6, when the denier number of the core yarn 9 is 1700 to 5200 de, an excellent belt strength retention rate is obtained, and the core with respect to the denier number of the driving yarn 6 at this time is obtained. The ratio of the denier number of the yarn 9 is 14.0 to 43.0%.
Met.

The round braid 7 assembled as described above is, for example, an epoxy resin, an isocyanate compound, an ethylene urea compound and a resorcinol-formalin latex (RAL) before being embedded in the backing rubber layer 1. An adhesive treatment or a stretching treatment is performed by a combination of adhesives made of the above. As a method of treating the adhesive, a dipping method is preferable because the adhesive must be uniformly impregnated from the surface to the inside of the round braid 7 constituting the reinforcing member 2.

The bending fatigue test of the toothed belt A for obtaining the data shown in FIGS. 5 to 7 was performed under the following conditions and procedures.

[Structure of Toothed Belt A of Example of the Present Invention] The round braid 7 constituting the reinforcing member 2 is a Kevlar 29 (trade name, manufactured by DuPont) four-stroke 1500 de (total denier number: 6000 de). The core yarn 9 of 50 to 1000 de made of Tetron is inserted and arranged in the hollow portion 8 of the thread, and the driving thread 6 constituting the round braid 7 is 0 to 20 times / 1.
A twist of 0 cm was applied, and a braid angle of 5 to 30 ° was used. The round braid 7 is first immersed in an isocyanate compound adhesive to form a sub-coat layer, and then resorcinol-formalin latex (R)
AL) to form a second coat layer
Then, it was immersed in CR glue rubber to form a top coat layer. During the bonding process, a stretching process was performed at the same time. The stretched braided braids 7, 7,... Are arranged spirally on the back rubber layer 1 made of CR rubber, and the rubber braided braid 7 is buried thereon. A plurality of round braided braids 7, 7,... Are formed by forming a vulcanized rubber layer 3 and forming and vulcanizing the surface of the tooth rubber layer 3 with a nylon cloth 5 attached to the surface thereof. The toothed belt A in which the reinforcing body 2 in which the core thread 9 is inserted and arranged in each hollow portion 8 is embedded in the belt body 4 was obtained. At the time of the adhesive treatment, the adhesive is uniformly impregnated from the surface of the round braid 7 to the inside.

[Bending Fatigue Test Procedure] As shown in FIG. 8, four large pulleys 10, 10,... And four small pulleys 11, 1 arranged between adjacent large pulleys 10, 10 are shown.
A belt bending tester provided with 1, 2,... Is provided, and the toothed belt is stretched over large and small pulleys 10, 11 of the belt bending tester, and a predetermined tension is applied to the toothed belt by weights 12. I ran at. Each of the small pulleys 1
The diameter of 1 is 30 mm. Also, the toothed belt makes one round and passes through each of the four small pulleys 11, 11,... Once, that is, the number of times of bending of the belt by each small pulley 11 is four times. In the data of FIGS. 5 to 7, the belt strength maintenance ratio is defined as the number of bending times of 1 × 10
⁸

As described above, in this embodiment, the round braid 7
The core yarn 9 is inserted into the central portion 8 of the yarn, and the twist coefficient K of the yarn 6 constituting the rounded braid 7 is specified as described above, and the yarn 6 is changed to a rightward yarn and a leftward yarn. And the respective twist directions are set in the opposite directions to S twist and Z twist, and the braid angle is set to 15 ° ± 5 °. Further, the ratio of the denier number of the core yarn 9 to the denier number of the yarn 6 constituting the round braid 7 was appropriately set according to the number of the yarns 6 constituting the round braid 7.

As a result, as a structural characteristic of the braided braid 7, a uniform stress is applied to the monofilament constituting the yarn 6, and the directionality of the driven yarn 6 can be eliminated by the S twist and the Z twist. Further, the abrasion between the filaments can be reduced, whereby the bending fatigue resistance can be greatly improved.

In addition, the yarns 6 can be better aligned by appropriate number of twists of the driving yarns 6, and
The core thread 6 of appropriate thickness can maintain a perfect circle,
The dimensional stability can be improved. Further, by setting the number of the driving yarns 6 to 4 to 8, the strength per cross-sectional area can be increased.

In the above embodiment, the toothed belt A is shown as an industrial belt. However, the present invention is not limited to this. For example, a transmission belt such as a V-belt, a flat belt, a ribbed belt, or a transport belt may be used. It goes without saying that it is good.

[0042]

As described above, according to the first to fourth aspects of the present invention, the reinforcing member is formed in a hollow portion of a round braid in which 4 to 8 even number of yarns are cylindrically assembled. And the twist coefficient K of the yarn constituting the above-mentioned braided braid.
Is set to 194 ± 155 in the following equation,

[0043]

(Equation 5)

T: the number of twists per 10 cm D: the number of deniers and the twist direction of the yarn constituting the braided braid is S twist and Z twist
It is composed of right-shifting yarn and left-turning yarn set in the opposite direction to the twist, and furthermore, the braid angle of the round braid is 15 ° ± 5.
° and the ratio of the denier number of the core yarn to the denier number of the yarns constituting the round braid is 2.5 to 7 when the round braid is braided with four yarns. .
7.5% when braided with 6 yarns to 5%
24.0%, 1 when braided with 8 yarns
Since each is set to 4.0 to 43.0%, dimensional stability can be further improved in addition to bending fatigue resistance.

[Brief description of the drawings]

FIG. 1 is an enlarged longitudinal side view of a round braid.

FIG. 2 is an enlarged front view of a round braid.

FIG. 3 is a vertical sectional front view of the toothed belt.

FIG. 4 is a data diagram showing the strength per cord cross-sectional area of a round braid.

FIG. 5 is a data diagram showing a relationship between the number of twists of a yarn and a belt strength maintenance rate.

FIG. 6 is a data diagram showing a relationship between a braid angle of a yarn and a belt strength maintaining ratio.

FIG. 7 is a data diagram showing the relationship between the denier number of the core yarn and the belt strength maintaining ratio.

FIG. 8 is a schematic configuration diagram of a belt bending tester.

[Explanation of symbols]

 2 Reinforcement 4 Belt body 6 Thread 7 Round braid 8 Hollow 9 Core thread A Toothed belt (industrial belt)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-244849 (JP, A) JP-A 48-6448 (JP, U) JP-A 60-19843 (JP, U) JP-A 244848 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16G 1/00-5/00 D04C 1/00-7/00 D07B 1/00-9/00

Claims (4)

(57) [Claims] An industrial belt in which a reinforcing member made of fiber is embedded in a belt body, wherein the reinforcing member has a hollow portion formed in a cylindrical shape by an even number of 4 to 8 yarns. And a core yarn provided in the hollow portion of the round braid. The yarn constituting the round braid has a twist coefficient K of 194 ± 155 in the following equation.
Is set to T: number of twists per 10 cm D: number of deniers, consisting of rightward and leftward yarns in which the twist direction is set in the opposite direction between S-twist and Z-twist, and furthermore, the braid angle of a braided braid Is set to 15 ° ± 5 °. 2. A round-braided braid is formed of four yarns in a cylindrical shape, and the ratio of the denier number of the core yarn to the denier number of the yarns constituting the round-braided braid is 2.5 to 2.5. 7.5
The industrial belt according to claim 1, wherein the ratio is set to%. 3. The round-braided braid is braided in a cylindrical shape with six yarns, and the ratio of the denier number of the core yarn to the denier number of the yarns constituting the round-braided braid is 7.5 to 7.5. 24.
2. The industrial belt according to claim 1, wherein the value is set to 0%. 4. The round-braided braid is cylindrically braided with eight yarns, and the ratio of the denier number of the core yarn to the denier number of the yarns constituting the round-braided braid is 14.0 to 4.0. 4
2. The industrial belt according to claim 1, wherein the setting is 3.0%.