JP2001124146A - Motive power transmission belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motive power transmission belt for improving the service life by improving bending performance of the belt by laminating extensible/ contractible canvas on a belt back face. SOLUTION: In a V ribbed belt 1 for laminating canvas 5 on a belt back face by arranging a compression rubber layer 4 adjacently to an adhesive rubber layer 3 for embedding a core cord 2 in the belt lengthwise direction, extensible/ contractible cotton yarn 10 for surrounding a core of urethane elastic yarn 13 by cotton yarn 14 as the canvas 5 laminated on the belt back face is used as at least one yarn of the warp 11 and the weft 12, and the extensible/ contractible cotton yarn 10 is arranged in the belt lengthwise direction.

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, and more particularly to a V-ribbed belt, a low-edge V-belt, and the like.
In a power transmission belt such as a flat belt, an elastic canvas is laminated on the back of the belt to improve the flexibility of the belt and improve the life of the belt.

[0002]

2. Description of the Related Art There is a V-ribbed belt as a transmission belt having a canvas. Japanese Patent Application Laid-Open No. Hei 4-151048 discloses a compressed rubber layer having a plurality of ribs extending in parallel with the longitudinal direction of the belt and having a plurality of ribs in a parallel state, a cushion layer having a core wire made of a rope buried thereon, and a back surface thereon Discloses a V-ribbed belt having a structure in which a sewing cloth joined with a sewing machine is adhered to the V-ribbed belt. This canvas is originally provided to maintain the vertical crack resistance of the belt, and is obtained by subjecting a plain woven fabric in which warp and weft yarns are woven to rubberization treatment.

Conventionally, a woven fabric widely used as a back canvas for a V-ribbed belt is a plain woven fabric having a crossing angle of 90 degrees between a warp and a weft, which is mechanically treated, that is, subjected to a tenter treatment so that both yarns are arranged in the longitudinal direction of the belt. Wide angle processing crossed at 120 degrees. The basic construction of this canvas is a canvas in which the number of belt drivings is 10 or more / 10 mm for both warp and weft, and the single yarn tensile force is 9 N or more / 10 cotton fiber yarns.
The plain fabric is forcibly subjected to a wide angle treatment, that is, a tenter treatment, with a spun yarn of 0%, so that the number of belts to be driven is 14 or more / 10 mm for both the warp and the weft.

[0004] In addition, the flexibility of the belt has been improved by arranging a woven fabric having a plurality of cords in the width direction on the back of the belt or using a knitted fabric.

[0005]

However, the canvas subjected to the wide-angle treatment is a plain woven fabric in which the warp and the weft intersect at 90 degrees.
A method of increasing the crossing angle between the warp and the weft by cutting the spliced fabric in the degree direction and joining it together, or performing a tenter treatment on a plain woven fabric in which the warp and the weft cross at 90 degrees, and continuing the woven cloth in the 45 degree direction In each case, it took a lot of time to make a wide angle canvas.

Further, when the cord of the woven fabric is arranged in the width direction of the belt, the rubber oozes out from the gap between the cords, and in a usage mode in which the pulley comes into contact with the back of the belt, a rubber adhesive adheres to the back of the belt. This was a major problem that caused pronunciation. Furthermore, when a knitted fabric is used, there is a problem that the belt performance is reduced because the knitted fabric has lower strength than the woven fabric.

The present invention addresses such a problem. In a power transmission belt such as a ribbed belt, a low-edge V-belt, and a flat belt, an elastic canvas is laminated on the back of the belt to improve the flexibility of the belt. It is another object of the present invention to provide a power transmission belt whose life is improved.

[0008]

That is, according to the first aspect of the present invention, a compression rubber layer is disposed adjacent to an adhesive rubber layer in which a core wire is embedded along the longitudinal direction of the belt, and a canvas is laminated on the back of the belt. In the power transmission belt, a stretchable cotton yarn, in which a cotton yarn is surrounded by a core of urethane elastic yarn, is used as at least one of a warp and a weft as a canvas to be laminated on the back of the belt, and the stretchable cotton yarn is The power transmission belt is arranged in the direction, and the elasticity of the belt is improved, the flexibility is improved, and the life of the belt is improved.

According to the invention of claim 2 of the present application, the power transmission belt comprises an adhesive rubber having a core buried along the belt longitudinal direction, and a compressed rubber layer having at least one rib portion along the belt longitudinal direction. Located on V-ribbed belt.

In the invention of claim 3 of the present application, the canvas is treated only with the resorcinol-formalin-latex liquid, and no rubber adheres to the surface of the canvas, so that the sound produced by the adhesion is produced even when the rear surface is driven. Can be blocked.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A V-ribbed belt 1 shown in FIG.
A core wire 2 made of a high-strength, low-elongation cord made of polyester fiber, aramid fiber, or glass fiber is embedded in an adhesive rubber layer 3, and a compression rubber layer 4 as an elastic layer is provided below the core wire. are doing. The compressed rubber layer 4 is provided with a plurality of ribs 7 having a substantially triangular cross section extending in the longitudinal direction of the belt, and a resorcinol-formalin-latex (RFL) treated canvas 5 is provided on the belt surface.

As shown in FIG. 3, the canvas 5 uses a stretchable cotton yarn 10 surrounding a cotton yarn 14 as a core of a urethane elastic yarn 13 for at least one of a warp yarn and a weft yarn. It is made of canvas woven in 90 ° plain weave, twill weave, satin weave, etc.
Is located. The volume ratio of the cotton yarn 14 and the urethane elastic yarn 13 constituting the elastic cotton yarn 10 is 3 to 5 in the ratio of the urethane elastic yarn 1 to the cotton yarn, and the cotton yarn completely surrounds the urethane elastic yarn. Covering.

A canvas 5 shown in FIG. 4 is used for a power transmission belt according to the present invention, and includes a warp 1 in a belt longitudinal direction.
1 shows a plain fabric using a stretchable cotton yarn 10 surrounding a cotton yarn 14 as a core of a urethane elastic yarn 13 and using a cotton yarn as a weft 12 in a direction perpendicular to this.

Thereafter, the canvas is bonded by RFL treatment to harden the canvas, and wrinkles of the tubular belt canvas are prevented from occurring in the spinning process. In the RFL treatment, the RFL solution is treated with 0.1%.
After soaking for 1 to 20 seconds, 30 to 6 at 100 to 200 ° C
Dry for 00 seconds. Of course, rubber glue can be attached to the RFL-treated canvas.

Subsequently, the width ends of the canvas are abutted irrespective of the front and back, and a sewing machine such as an overlock using a monofilament such as cotton yarn, nylon, vinylon, or polyester, or a multifilament is sewn along the longitudinal direction (a). To form a tubular canvas having one joint portion, and the V-ribbed belt canvas 5.

The RFL solution used here is a mixture of an initial condensate of resorcinol and formalin and a rubber latex. In this case, the molar ratio of resorcinol to formalin should be 1: 0.5 to 3 to obtain an adhesive force. It is suitable for increasing the value. The initial condensate of resorcinol and formalin is
This is mixed with the latex so that the resin content is 10 to 100 parts by weight with respect to 100 parts by weight of the rubber content of the latex, and the total solid content is adjusted to a concentration of 5 to 40%. In some cases, a carbon black liquid is appropriately mixed with the RFL liquid to blacken the treated material. Also, RF
It is advisable to add 0.1 to 1.0% by weight of a known surfactant to the L liquid.

The latex is styrene-butadiene-
Vinylpyridine terpolymer, chlorosulfonated polyethylene, hydrogenated nitrile rubber, epichlorohydrin,
Latex such as natural rubber, SBR, chloroprene rubber, olefin-vinyl ester copolymer, and EPDM.

As the polymer used for the compressed rubber layer 4, hydrogenated nitrile rubber, chloroprene rubber, natural rubber, CSM, ACSM, SBR, ethylene-alpha-olefin elastomer is used, and hydrogenated nitrile rubber is hydrogenated. It is preferably at least 90% in order to exhibit heat resistance and ozone resistance characteristics. Hydrogenated nitrile rubber with a hydrogenation rate of less than 80%
Heat resistance and ozone resistance are extremely reduced. Considering oil resistance and cold resistance, the amount of bound acrylonitrile is 20 to 4
A range of 5% is preferred. Among them, an ethylene-alpha-olefin elastomer having oil resistance and cold resistance is preferable.

A typical example of the ethylene-alpha-olefin elastomer is EPDM, which is an ethylene-propylene-diene monomer. Examples of diene monomers include dicyclopentadiene, methylene norbornene, ethylidene norbornene, 1,4-hexadiene, cyclooctadiene, and the like. In addition, ethylene-propylene rubber (EP
R) can also be used.

For crosslinking of the rubber, sulfur or an organic peroxide is used. Examples of the organic peroxide include dicumyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, and benzoyl peroxide. ,
1,3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3,2,5-dimethyl-2,5-
(Benzoylperoxy) hexane, 2,5-dimethyl-2,5-mono (t-butylperoxy) hexane, and the like. This organic peroxide is used alone or as a mixture in the range of 0.005 to 0.02 mol g per 100 g of the ethylene-alpha-olefin elastomer.

Further, by blending a crosslinking assistant (co-agent), the degree of crosslinking can be increased to prevent problems such as adhesive wear. Examples of the crosslinking aid include TIAC, TAC, 1,2 polybutadiene, metal salts of unsaturated carboxylic acids, oximes, guanidine, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, NN′-m- It is usually used for peroxide crosslinking such as phenylene bismaleimide and sulfur.

If necessary, ordinary rubbers such as carbon black, reinforcing agents such as silica, fillers such as calcium carbonate and talc, plasticizers, stabilizers, processing aids, and coloring agents. What is used in the formulation is used.

Also, short fibers made of nylon 6, nylon 66, polyester, cotton, and aramid are mixed into the compressed rubber layer 4 to improve the lateral pressure resistance of the compressed rubber layer 4 and to be in contact with the pulley. The short fibers protrude from the surface of the compressed rubber layer 4 to reduce the friction coefficient of the compressed rubber layer 4 and reduce noise during belt running. Of these staple fibers, aramid staple fibers having rigidity, strength and abrasion resistance are most effective.

In order for the aramid short fibers to sufficiently exhibit the above-mentioned effects, the fiber length of the aramid fibers should be 1 to 20.
In mm, the amount is 1 to 30 parts by weight per 100 parts by weight of the ethylene-alpha-olefin elastomer. The aramid fiber is an aramid having an aromatic ring in its molecular structure, such as, for example, Conex, Nomex, Kevlar, Technora, Twaron and the like.

When the amount of the aramid short fibers is less than 1 part by weight, the rubber of the compressed rubber layer 4 tends to stick and wears out. On the other hand, when the amount exceeds 30 parts by weight, the short fibers are reduced. It is not evenly dispersed in rubber. However, the addition of this aramid short fiber is not essential, and may be the one to which short fibers made of other materials are added.

As the cord 4, polyester fiber,
Aramid fiber and glass fiber are used, and among them, a cord obtained by twisting a polyester fiber filament group having ethylene-2,6-naphthalate as a main constituent unit and having a total denier of 4,000 to 8,000 is a belt. It is preferable to maintain the strength retention and extend the life of the belt. The twist number of this cord is 10-23 / 10
cm, and the number of twists is 17 to 38/10 cm. If the total denier is less than 4,000, the modulus and strength of the cord become too low, and if it exceeds 8,000, the belt becomes thick and the bending fatigue becomes poor.

The above ethylene-2,6-naphthalate is
Usually, naphthalene-2,6-dicarboxylic acid or an ester-forming derivative thereof is synthesized by condensation polymerization with ethylene glycol under appropriate conditions in the presence of a catalyst. At this time, if one or more appropriate third components are added before the completion of the polymerization of ethylene-2,6-naphthalate, a copolymer polyester is synthesized.

The core 4 is subjected to an adhesive treatment for the purpose of improving the adhesiveness with rubber. As such an adhesive treatment, the fiber is made of resorcin-formalin-latex (RF
L) Generally, after immersion in the liquid, the adhesive layer is uniformly formed on the surface by heating and drying. However, without being limited to this, there is a method of performing a pretreatment with an epoxy or isocyanate compound and then treating with an RFL solution.

The cord subjected to the bonding treatment has a spinning pitch, that is, a core winding pitch of 1.0 to 1.3 m.
By setting m, it is possible to finish the belt with a high modulus. If the length is less than 1.0 mm, the cord cannot ride on the adjacent cord and cannot be wound.
m, the modulus of the belt gradually decreases

On the other hand, the adhesive rubber layer 3 is made of the same kind of rubber as the compressed rubber layer 4 because it has heat resistance. However, short fibers are not mixed in, but if necessary, carbon black, a reinforcing agent such as silica, a filler such as calcium carbonate and talc, a plasticizer, a stabilizer, a processing aid, a normal coloring agent such as a coloring agent. What is used for rubber compounding is used.

A typical method of manufacturing a V-ribbed belt is as follows. First, after wrapping a canvas and an adhesive rubber layer around the peripheral surface of a cylindrical forming drum, a cord made of a rope is spirally spun on this, and then an adhesive rubber layer and a compressed rubber layer are sequentially wound. After obtaining the laminate, it is crosslinked to obtain a sleeve.

Next, the bridging sleeve is hung on a driving roll and a driven roll, and is run under a predetermined tension. Further, the rotated grinding wheel is moved so as to contact the running bridging sleeve, and the bridging sleeve is moved. 3 to 100 on the compressed rubber layer surface
The plurality of groove portions are polished at a time.

The bridging sleeve obtained in this manner is removed from the driving roll and the driven roll, and the bridging sleeve is hung on another driving roll and the driven roll to run, cut into a predetermined width by a cutter, and individually cut. Finish the V-ribbed belt.

Further, in the present invention, in addition to the above-mentioned V-ribbed belt, a low-edge V-belt 8 having canvas attached only to the upper and lower surfaces of the belt as shown in FIG. 2 is also included. The belt 8 has a core wire 2 embedded in an adhesive rubber layer 3 and a compression rubber layer 4 as an elastic body layer below the core wire 2. Cogs may be provided on the compressed rubber layer 4 at predetermined intervals along the longitudinal direction.

[0035]

The present invention will be described in more detail with reference to the following examples. Example 1 In the V-ribbed belt manufactured in this example, a warp (cotton 10 ^S + spandex 155 dtex) as shown in FIG. 4 was used.
/ 1 and wefts (cotton 20 ^S / 2), the warp density of 75 present / 5c
m, a plain weave having a weft density of 75/5 cm and a crossing angle of 90 ° between the warp and the weft was prepared using an RFL solution (vinyl pyridine latex (40%): 244 parts by weight, resorcinol 11 parts by weight: 37% formalin 16.2). Parts by weight: 0.3 parts by weight of sodium hydroxide: 299.5 parts by weight of water: 41% by weight of a carbon dispersion (28%):
The fabric was dried to obtain a treated canvas, cut into a predetermined length in a direction perpendicular to the warp, and subjected to sewing joint to form a cylindrical canvas.

Total densities of 1,000 denier ethylene-2,6-naphthalate fiber (PEN fiber) twisted in a 2 × 3 twist configuration with an upper twist coefficient of 3.0 and a lower twist coefficient of 3.0 as a core wire. A denier 6,000 cord subjected to an adhesive treatment was used.

Table 1 shows the compression rubber and the adhesive rubber layer, respectively.
, Kneaded with a Banbury mixer and then rolled with calender rolls. The compressed rubber layer contains short fibers and is oriented in the belt width direction.

[0038]

[Table 1]

The method of manufacturing the V-ribbed belt is an ordinary method. First, one ply of the above-mentioned tubular canvas is inserted into a drum as a canvas, and then an adhesive rubber layer is wound thereon, and the cord is spun and further compressed. After disposing the rubber layer, a crosslinking jacket is inserted over the compressed rubber layer. Next, the mold was placed in a vulcanizing can and crosslinked, and then the tubular crosslinked sleeve was removed from the mold. The compression rubber layer of the removed sleeve was formed into a rib by a grinder, and cut into individual belts from the formed body. The obtained V-ribbed belt is a K-type 3-ribbed belt having a length of 1,000 mm according to the RMA standard, a rib pitch of 3.56 mm and a rib height of 2.
0 mm, belt thickness 4.3 mm, rib angle 40 °.

The running life of the V-ribbed belt obtained in this manner was evaluated for running life of the belt, time from RFL treatment of the used canvas to finishing into a tubular canvas, canvas strength, elongation at cutting, and the like. Table 2 shows the results. The strength of the canvas and the elongation at the time of cutting were measured for the tensile strength and the elongation in the longitudinal direction of the belt in accordance with JIS L1096 for the RFL-treated canvas.

The running test machine used for the evaluation of the endurance running test includes a driving pulley (120 mm in diameter), a driven pulley (120 mm in diameter), and an idler pulley (85 m in diameter).
m) and a tension pulley (diameter: 45 mm). A belt is hung on each pulley of the testing machine, the ambient temperature is 120 ° C., the number of rotations of the driving pulley is 49.
The driven pulley was driven at 12 horsepower at 00 rpm, and the tension pulley was run with an initial tension of 559 N / 3 rib.

The idler pulley is engaged at the back of the V-ribbed belt 1, and its wrapping angle is about 120 degrees. According to this running test method, the time until cracks occurred in the rib portions of the belt was measured.

Example 2 As cylindrical canvas, warp (cotton 20 ^S / 2) and weft (cotton 1) were used.
0 ^S + spandex 155 dtex) / 1), a plain woven fabric having a warp density of 75 yarns / 5 cm and a weft yarn density of 75 yarns / 5 cm is treated with an RFL liquid, and then cut by rotating the weft yarn by 90 degrees so as to be in the longitudinal direction of the belt. The sewing machine was joined to form a cylindrical canvas. Otherwise, a V-ribbed belt was manufactured in the same manner as in Example 1. The running life of the V-ribbed belt obtained in this manner was evaluated for the running life of the belt, the preparation time of the canvas until RFL processing from a white background canvas into a tubular canvas, the strength of the canvas, the elongation at the time of cutting, and the like. The results are shown in Table 2.

Comparative Example 1 Both warp and weft (cotton 20 ^S / 2), warp density 75
After processing with a plain weave RFL solution having a density of 5/5 cm and a weft density of 75/5 cm and a crossing angle between the warp and the weft of 90 degrees, this plain fabric is cut into a predetermined length in a direction perpendicular to the warp and the sewing machine. Jointed into cylindrical canvas. Otherwise, a V-ribbed belt was manufactured in the same manner as in Example 1. The running life of the belt, the preparation time of the canvas, the strength of the canvas, the elongation at the time of cutting, and the like were evaluated by the durability running test of the V-ribbed belt thus obtained. The results are shown in Table 2.

Comparative Example 2 As shown in FIG. 5, both the warp 11 and the weft 12 (cotton 2
^0S / 2), a warp density of 75 yarns / 5cm, a weft density of 75 yarns / 5cm, and a crossing angle of 90 ° between the warp and the weft is treated with the RFL liquid, and then the plain weave is oriented in the 45 ° direction. This was cut, and the cut length was subjected to a sewing machine joint to form a cylindrical canvas in which the crossing angle between the warp and the weft was 90 degrees. Otherwise, a V-ribbed belt was manufactured in the same manner as in Example 1. The running life of the belt, the preparation time of the canvas, the strength of the canvas, the elongation at the time of cutting, and the like were evaluated by the durability running test of the V-ribbed belt thus obtained. The results are shown in Table 2.

Comparative Example 3 As shown in FIG. 6, both the warp yarn 11 and the weft yarn 12 (cotton 2
0 ^S / 2), a warp density of 75 warp / 5 cm, a plain weave having a weft density of 75 warp / 5 cm and an intersecting angle of 90 ° between the warp and the weft, was subjected to a tenter treatment to make the intersecting angle between the warp and the weft 120 °. A wide-angle canvas was finished, cut into a predetermined length in a direction perpendicular to the longitudinal direction of the canvas, and machine-joined to form a cylindrical canvas with a crossing angle of warp and weft of 120 degrees. Others are Example 1.
A V-ribbed belt was produced in the same manner as in the above. The running life of the belt, the preparation time of the canvas, the strength of the canvas, the elongation at the time of cutting, and the like were evaluated by the durability running test of the V-ribbed belt thus obtained. The results are shown in Table 2.

[0047]

[Table 2]

As is apparent from the results shown in Table 2, in the example, the canvas preparation time can be shortened, and the running time of the belt is not inferior.

[0049]

As described above, according to the present invention, a stretchable cotton yarn in which a urethane elastic yarn is surrounded by a cotton yarn core is used as at least one of a warp yarn and a weft yarn as a canvas laminated on the back of the belt. A power transmission belt in which stretchable cotton yarns are arranged in the longitudinal direction of the belt, the stretchability of the belt is improved, the flexibility is improved, the life of the belt is improved, and the tubular canvas used for the belt is also used. The finish can be completed in a short time, and when rubber is not attached to the surface of the canvas, there is an effect that sound generation due to adhesion can be prevented even when the rear surface is driven.

[Brief description of the drawings]

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

FIG. 2 is a vertical sectional view of a V-belt according to the present invention.

FIG. 3 is a schematic view of a stretchable cotton yarn in which a cotton yarn is surrounded by a core of a urethane elastic yarn.

FIG. 4 is a plan view of a canvas used for the power transmission belt according to the present invention.

FIG. 5 is a plan view of a canvas used in Comparative Example 2.

FIG. 6 is a plan view of a canvas used in Comparative Example 3.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 V-ribbed belt 2 core wire 3 Adhesive rubber layer 4 Compressed rubber layer 5 Canvas 7 Rib part 10 Elastic cotton yarn 11 Warp 12 Weft 13 Urethane elastic yarn 14 Cotton yarn

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // D06M 101: 38 D06M 101: 38 F term (Reference) 4L033 AA02 AA06 AB03 CA12 CA34 4L048 AA08 AA20 AA26 AB12 AB19 BA01 BA02 CA04 CA15 DA38 DA44

Claims (3)

[Claims] 1. A power transmission belt in which a compression rubber layer is disposed adjacent to an adhesive rubber layer in which a cord is embedded along a longitudinal direction of a belt, and a canvas is laminated on the back of the belt. A belt for power transmission, wherein a stretchable cotton yarn surrounding a cotton yarn is used for at least one of a warp and a weft as a core of a urethane elastic yarn, and the stretchable cotton yarn is arranged in the belt longitudinal direction. . 2. The power transmission belt according to claim 1, wherein the power transmission belt is a V-ribbed belt comprising an adhesive rubber having a core buried in the belt longitudinal direction and a compression rubber layer having at least one rib portion along the belt longitudinal direction. A power transmission belt according to claim 1. 3. The power transmission belt according to claim 1, wherein the canvas is treated only with a resorcin-formalin-latex liquid.