JP5227835B2 - Friction transmission belt - Google Patents

Description

  The present invention relates to a friction transmission belt in which a belt body is wound so as to contact a pulley and transmits power.

  In recent years, there has been an increasing need to prevent the generation of abnormal noise in a V-ribbed belt while driving a car. There are many types of abnormal noise of the V-ribbed belt, and one of them is belt slip noise when wet.

In contrast, Patent Document 1, a rib portion which is a friction transmission surface with respect to 100 parts by weight of ethylene -α- olefin elastomer, solubility parameter ^{8.3~10.7 (cal / cm 3) 1} / It is disclosed that the rubber composition is composed of 10 to 25 parts by weight of a plasticizer ² and 60 to 110 parts by weight of an inorganic filler.

  Patent Document 2 discloses that the transmission surface is formed of a rubber composition containing 5 parts by weight or more of a hydrophilic inorganic filler with respect to 100 parts by weight of rubber.

  In Patent Document 3, the compressed rubber layer is composed of 10 to 40 parts by weight of polyamide short fibers, 30 to 60 parts by weight of carbon black with respect to 100 parts by weight of an ethylene-α-olefin elastomer having an ethylene content of 50 to 70% by weight, Tan δ obtained by measuring dynamic viscoelasticity in tensile mode at a frequency of 10 Hz and a temperature of 0 ° C. is 0.080 or more by blending 10 to 60 parts by weight of an inorganic filler composed of metal carbonate and / or metal silicate. It is disclosed to form with a rubber composition.

  Patent Document 4 discloses that a rib portion serving as a friction transmission surface is composed of a rubber composition in which 1 to 25 parts by weight of a surfactant is blended with 100 parts by weight of an ethylene-α-olefin elastomer. Yes.

  Patent Document 5 discloses that the rib portion serving as the friction transmission surface is composed of a rubber composition in which 5 to 25 parts by weight of an ether ester plasticizer is blended with 100 parts by weight of the ethylene-α-olefin elastomer. Has been.

JP 2007-232205 A JP 2007-120526 A JP 2006-64174 A JP 2008-185162 A JP 2008-195914 A

  However, in the configuration of Patent Document 1, there is a problem that abnormal noise is likely to be generated when the plasticizer is bleeded and adhesive wear or water is not applied.

  In the configuration of Patent Document 2, the wettability of the hydrophilic inorganic filler with water is not sufficient, and it cannot be said that the noise suppression effect is sufficient under high load conditions.

  With the configuration of Patent Document 3, a sufficient noise suppression effect cannot be exhibited in a state in which the slip rate is very large as in the case of flooding.

  In patent documents 4 and 5, since the affinity with water on the rubber surface is insufficient, a sufficient noise suppression effect cannot be exhibited.

  An object of the present invention is to obtain a friction transmission belt that exhibits a high noise suppressing effect when wet.

The present invention is a friction transmission belt that is wound so that the belt body comes into contact with the pulley and transmits power,
At least the pulley contact portion of the belt main body is 30-80 of at least one layered silicate selected from smectite group, vermulite group, and kaolin group with respect to 100 parts by mass of raw rubber containing ethylene-α-olefin elastomer. It is formed with the rubber composition mix | blended by mass part.

  According to the present invention, at least the pulley contact portion of the belt main body is at least one layered silicic acid selected from smectite group, vermulite group, and kaolin group with respect to 100 parts by mass of the raw rubber containing ethylene-α-olefin elastomer. Since it is formed with a rubber composition in which 30 to 80 parts by mass of salt is blended, it is possible to obtain a high noise suppressing effect when wet.

It is a perspective view which shows the V-ribbed belt which concerns on embodiment. It is a figure which shows the pulley layout of the belt running test machine for abnormal noise evaluation at the time of flooding. It is a figure which shows the pulley layout of the belt running test machine for heat-resistant durability evaluation. It is a figure which shows the pulley layout of the belt running test machine for abrasion evaluation.

  Hereinafter, embodiments will be described in detail with reference to the drawings.

  FIG. 1 shows a V-ribbed belt B (friction transmission belt) according to this embodiment. The V-ribbed belt B is used, for example, to constitute an auxiliary machine drive belt transmission provided in an engine room of an automobile, and has a belt circumferential length of 700 to 3000 mm, a belt width of 10 to 36 mm, and a belt thickness. 4.0-5.0 mm.

  The V-ribbed belt B includes a V-ribbed belt main body 10 configured as a triple layer of a compression rubber layer 11 on the inner peripheral side of the belt, an intermediate adhesive rubber layer 12 and a back rubber layer 13 on the outer peripheral side of the belt. A core wire 14 is embedded in the layer 12 so as to form a spiral having a pitch in the belt width direction.

  The compressed rubber layer 11 is provided such that a plurality of V ribs 15 constituting a pulley contact portion hang down to the inner peripheral side of the belt. Each of the plurality of V ribs 15 is formed in a ridge having a substantially inverted triangular cross section extending in the belt length direction, and arranged in parallel in the belt width direction. Each V rib 15 is formed, for example, with a rib height of 2.0 to 3.0 mm and a width between base ends of 1.0 to 3.6 mm. Moreover, the number of ribs is 3-6, for example (in FIG. 1, the number of ribs is 6). The compressed rubber layer 11 is formed of a rubber composition obtained by heating and pressurizing an uncrosslinked rubber composition in which various compounding agents are blended and mixed with raw rubber to be crosslinked with a crosslinking agent.

  The raw rubber of the rubber composition that forms the compressed rubber layer 11 contains an ethylene-α-olefin elastomer. Examples of the ethylene-α-olefin elastomer include ethylene-propylene-diene rubber (EPDM), ethylene-propylene copolymer (EPM), ethylene-butene copolymer (EBM), and ethylene-octene copolymer (EOM). The ethylene-α-olefin elastomer contained in the raw rubber may be composed of a single type or may be composed of a blend of a plurality of types. The ethylene content of the ethylene-α-olefin elastomer is, for example, 50 to 80% by mass.

  The content of the ethylene-α-olefin elastomer in the raw rubber is preferably 60% by mass or more, more preferably 80% by mass or more, and 100%, that is, the raw rubber is ethylene-α-. Most preferably, it is composed only of an olefin elastomer. Examples of other rubber included in the raw rubber include chloroprene rubber (CR), chlorosulfonated polyethylene rubber (CSM), hydrogenated acrylonitrile rubber (H-NBR), and the like.

  Examples of the compounding agent include reinforcing materials such as carbon black, layered silicates, vulcanization accelerators, crosslinking agents, anti-aging agents, and softening agents.

  As carbon black, for example, channel black; furnace black such as SAF, ISAF, N-339, HAF, N-351, MAF, FEF, SRF, GPF, ECF, N-234; FT, MT, etc. Thermal black; acetylene black. Silica is also mentioned as a reinforcing agent. The reinforcing agent may be composed of a single species or a plurality of species. The reinforcing material preferably has a blending amount of 30 to 80 parts by mass with respect to 100 parts by mass of the raw rubber from the viewpoint that the balance between wear resistance and flex resistance becomes good.

  The layered silicate is composed of at least one selected from the smectite group, vermulite group, and kaolin group. Therefore, the layered silicate may be composed of a single species of smectite group, vermulite group, and kaolin group, and among smectite group, vermulite group, and kaolin group. It may be composed of any plural kinds, and may be composed of plural kinds selected from at least one kind of smectite group, at least one kind of vermulite group, and at least one kind of kaolin group.

  Examples of the smectite group include montmorillonite, beidellite, saponite, and hectorite. Examples of the vermulite family include 3 octahedral vermulites, 2 octahedral vermulites, and the like. Examples of the kaolin family include kaolinite, dickite, halloysite, lizardite, amesite, and chrysotile. Of these, the layered silicate is preferably a smectite montmorillonite.

  The layered silicate preferably has a particle size of 0.05 to 120 μm, and more preferably 0.5 to 80 μm. The amount of the layered silicate based on 100 parts by mass of the raw rubber is 30 to 80 parts by mass, preferably 30 to 60 parts by mass, and more preferably 30 to 45 parts by mass.

  Thus, in the V-ribbed belt according to the present embodiment, the compressed rubber layer 11 formed with the V-rib 15 constituting the pulley contact portion of the V-ribbed belt main body 10 is added to 100 parts by mass of the raw rubber containing the ethylene-α-olefin elastomer. On the other hand, since it is formed of a rubber composition containing 30 to 80 parts by mass of at least one layered silicate selected from the smectite group, vermulite group, and kaolin group, it has a high noise suppressing effect when exposed to water. Can be obtained.

  Examples of the vulcanization accelerator include metal oxides such as magnesium oxide and zinc oxide (zinc white), fatty acids such as metal carbonates and stearic acid, and derivatives thereof. The vulcanization accelerator may be composed of a single species or a plurality of species. The amount of the vulcanization accelerator based on 100 parts by mass of the raw rubber is, for example, 0.5 to 8 parts by mass.

  Examples of the crosslinking agent include sulfur and organic peroxides. As the crosslinking agent, sulfur may be used, organic peroxide may be used, or both of them may be used in combination. In the case of sulfur, the cross-linking agent is preferably 0.5 to 4.0 parts by mass with respect to 100 parts by mass of the raw rubber, and in the case of organic peroxide, the amount of the cross-linking agent is 100 parts by mass of the raw rubber. .5 to 8 parts by mass.

  Antiaging agents include amine-based, quinoline-based, hydroquinone derivatives, phenol-based, and phosphite-based agents. The anti-aging agent may be composed of a single species or a plurality of species. The amount of the anti-aging agent is, for example, 0 to 8 parts by mass with respect to 100 parts by mass of the raw rubber.

  Examples of the softener include petroleum softeners, mineral oil softeners such as paraffin wax, castor oil, cottonseed oil, sesame oil, rapeseed oil, soybean oil, palm oil, palm oil, fallen raw oil, waxy wax, rosin And vegetable oil-based softeners such as pine oil. The softener may be composed of a single species or a plurality of species. The amount of the softener other than the petroleum softener is 2 to 30 parts by mass with respect to 100 parts by mass of the raw rubber.

  It is preferable that the short fiber 16 is blended in the rubber composition forming the compressed rubber layer 11. It is preferable that the short fiber 16 is provided so as to be oriented in the belt width direction, and a part of the short fiber 16 is exposed and protrudes from the surface of the V rib 15.

  Examples of the short fibers 16 include nylon short fibers, vinylon short fibers, aramid short fibers, polyester short fibers, and cotton short fibers. The short fiber 16 is obtained by, for example, cutting a long fiber that has been subjected to an adhesion treatment to be heated after being immersed in a resorcin / formalin / latex aqueous solution (hereinafter referred to as “RFL aqueous solution”) into a predetermined length along the length direction. Manufactured. For example, the short fibers 16 have a length of 0.2 to 5.0 mm and a fiber diameter of 10 to 50 μm. The amount of the short fiber 16 is 3 to 50 parts by mass with respect to 100 parts by mass of the raw rubber. In addition, the structure by which the short fiber 16 was not planted in the rubber composition, and the short fiber was planted on the V rib 15 surface may be sufficient.

  The rubber composition forming the compressed rubber layer 11 preferably has a mass change rate of 0.1% or more when immersed in water for 1 minute, more preferably 0.2% or more. The rubber composition forming the compressed rubber layer 11 preferably has a mass change rate of not less than 0.3% and more preferably not less than 0.4% when immersed in water for 10 hours. The mass change rate can be calculated by a calculation method according to JIS K6258 by performing a test in which a test piece according to JIS K6258 is immersed in water on both sides for 1 minute or 10 hours.

  The adhesive rubber layer 12 is formed in a band shape having a horizontally long cross section, and is formed to have a thickness of 1.0 to 2.5 mm, for example. The back rubber layer 13 is also formed in a band shape having a horizontally long cross section, and has a thickness of 0.4 to 0.8 mm, for example. The adhesive rubber layer 12 and the back rubber layer 13 are formed of a rubber composition obtained by heating and pressurizing an uncrosslinked rubber composition in which various compounding agents are blended and mixed with raw rubber and then crosslinking with a crosslinking agent. . In addition, instead of the back rubber layer 13, for example, a reinforcing cloth made of a woven fabric, a knitted fabric, a non-woven fabric, or the like formed of yarn such as cotton, polyamide fiber, polyester fiber, or aramid fiber may be provided.

  Examples of the raw rubber for the rubber composition forming the adhesive rubber layer 12 and the back rubber layer 13 include ethylene-α-olefin elastomer, chloroprene rubber (CR), chlorosulfonated polyethylene rubber (CSM), hydrogenated acrylonitrile rubber ( H-NBR) and the like. The raw rubber for the adhesive rubber layer 12 is preferably the same as the raw rubber for the compressed rubber layer 11.

  Examples of the compounding agent include a reinforcing material such as carbon black, a vulcanization accelerator, a crosslinking agent, an anti-aging agent, a softening agent and the like, as in the case of the compressed rubber layer 11.

  The compressed rubber layer 11, the adhesive rubber layer 12, and the back rubber layer 13 may be formed of a rubber composition having a different composition, or may be formed of a rubber composition having the same composition.

  The core wire 14 is composed of twisted yarns such as polyester fiber (PET), polyethylene naphthalate fiber (PEN), aramid fiber, and vinylon fiber. The core wire 14 is subjected to an adhesive treatment that is heated after being immersed in an RFL aqueous solution before molding and / or an adhesive treatment that is dried after being immersed in rubber paste in order to impart adhesion to the V-ribbed belt main body 10. .

  The V-ribbed belt B according to the present embodiment is used by being wound around, for example, a crankshaft pulley, a power steering pulley, an AC generator pulley, a tensioner pulley, a water pump pulley, and an air conditioner pulley in an accessory drive belt transmission. .

  Further, the V-ribbed belt B according to the present embodiment can be manufactured by a known method.

  In this embodiment, the V-ribbed belt B is used. However, the present invention is not limited to this, and a low-edge type V-belt may be used.

(Rubber composition)
The following rubber compositions 1-14 were prepared. The respective configurations are also shown in Tables 1 and 2.

<Rubber composition 1>
EPDM (trade name: EPT3045 manufactured by Mitsui Chemicals) is used as a raw rubber, and 60 parts by weight of HAF carbon black (trade name: Seast SO manufactured by Tokai Carbon Co., Ltd.) and montmorillonite (manufactured by Hojun Co., Ltd.) with respect to 100 parts by weight of the raw rubber. Name: Bengel A) 30 parts by mass, zinc oxide (trade name: Zinc Hana No. 2 manufactured by Sakai Chemical Industry Co., Ltd.) 5 parts by mass, anti-aging agent (trade name: NOCRACK MB manufactured by Ouchi Shinsei Chemical Co., Ltd.) 2 parts by mass, paraffin Oil (made by Idemitsu Kosan Co., Ltd., trade name: Diana Process Oil PS-90), 10 parts by mass, sulfur (trade name: Oil Sulfur, made by Hosoi Chemical Co., Ltd.), 3 parts by mass, vulcanization accelerator (product made by Sanshin Chemical Co., Ltd.) Name: TET, EZ, MSA) 1.4 parts by mass and short fiber (product name: Leona 66, fiber length 1 mm, manufactured by Asahi Kasei Co., Ltd.) 30 parts by mass are mixed for about 5 minutes in a closed kneader. The uncrosslinked rubber composition obtained by kneading was rubber composition 1.

<Rubber composition 2>
An uncrosslinked rubber composition having the same structure as that of the rubber composition 1 except that 30 parts by mass of hectorite (trade name: Smecton HE manufactured by Kunimine Kogyo Co., Ltd.) is mixed with 100 parts by mass of the raw rubber instead of montmorillonite. Composition 2 was obtained.

<Rubber composition 3>
An uncrosslinked rubber composition having the same structure as the rubber composition 1 except that kaolinite (trade name: hard top clay manufactured by Shiroishi Calcium Industry Co., Ltd.) is blended in 30 parts by mass with respect to 100 parts by mass of the raw rubber instead of montmorillonite. Was rubber composition 3.

<Rubber composition 4>
The rubber composition 4 was an uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that the blending amount of montmorillonite was 45 parts by mass with respect to 100 parts by mass of the raw rubber.

<Rubber composition 5>
An uncrosslinked rubber composition having the same structure as that of the rubber composition 1 except that the blending amounts of HAF carbon black and montmorillonite are 55 parts by mass and 45 parts by mass with respect to 100 parts by mass of the raw rubber, respectively. did.

<Rubber composition 6>
An uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that the blending amounts of HAF carbon black and montmorillonite are 60 parts by mass and 60 parts by mass with respect to 100 parts by mass of the raw rubber, respectively. did.

<Rubber composition 7>
An uncrosslinked rubber composition having the same structure as that of the rubber composition 1 except that the blending amounts of HAF carbon black and montmorillonite are 50 parts by mass and 60 parts by mass with respect to 100 parts by mass of the raw rubber, respectively. did.

<Rubber composition 8>
An uncrosslinked rubber composition having the same structure as that of the rubber composition 1 except that the blending amounts of HAF carbon black and montmorillonite are 45 parts by weight and 80 parts by weight with respect to 100 parts by weight of the raw rubber, respectively. did.

<Rubber composition 9>
An uncrosslinked rubber composition having the same structure as the rubber composition 1 except that 30 parts by mass of talc (trade name: Microace P-8, manufactured by Nippon Talc Co., Ltd.) is blended with 100 parts by mass of the raw rubber instead of montmorillonite. Was rubber composition 9.

<Rubber composition 10>
An uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that 30 parts by mass of magnesium oxide (trade name: MgO-EL, manufactured by Kyowa Chemical Industry Co., Ltd.) is blended with 100 parts by mass of the raw rubber instead of montmorillonite. Was rubber composition 10.

<Rubber composition 11>
An uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that 30 parts by mass of zinc powder (product name: zinc powder R, manufactured by Hakusui Tec Co., Ltd.) is blended with 100 parts by mass of the raw rubber instead of montmorillonite. Rubber composition 11 was obtained.

<Rubber composition 12>
An uncrosslinked rubber having the same structure as the rubber composition 1 except that 10 parts by mass of a plasticizer (trade name: Adeka Sizer RS700 manufactured by ADEKA) is blended with 100 parts by mass of the raw rubber instead of montmorillonite and paraffinic oil The composition was rubber composition 12.

<Rubber composition 13>
An uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that 10 parts by mass of a surfactant (trade name: Areflux 54, manufactured by Rhein Chemie Japan) is blended with 100 parts by mass of the raw rubber instead of montmorillonite. The product was designated as a rubber composition 13.

<Rubber composition 14>
Except that 10 parts by mass of water-absorbing resin 1 (trade name: Aqua Keep 10SH-NF, manufactured by Sumitomo Seika Co., Ltd.) instead of montmorillonite was mixed with 100 parts by mass of the raw rubber, the rubber composition 1 had the same composition. The crosslinked rubber composition was designated as rubber composition 14.

<Rubber composition 15>
An uncrosslinked rubber having the same structure as the rubber composition 1 except that 10 parts by mass of water-absorbent resin 2 (product name: Aqua Coke TWB, manufactured by Sumitomo Seika Co., Ltd.) is blended with 100 parts by mass of the raw rubber instead of montmorillonite. The composition was rubber composition 15.

<Rubber composition 16>
The rubber composition 16 was an uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that the blending amount of montmorillonite was 3 parts by mass with respect to 100 parts by mass of the raw rubber.

<Rubber composition 17>
The rubber composition 17 was an uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that the blending amount of montmorillonite was 15 parts by mass with respect to 100 parts by mass of the raw rubber.

<Rubber composition 18>
The rubber composition 18 was an uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that the blending amount of montmorillonite was 25 parts by mass with respect to 100 parts by mass of the raw rubber.

<Rubber composition 19>
The rubber composition 19 was an uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that the blending amount of montmorillonite was 90 parts by mass with respect to 100 parts by mass of the raw rubber.

<Rubber composition 20>
The rubber composition 20 was an uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that montmorillonite was not blended.

<Rubber composition 21>
An uncrosslinked rubber composition having the same configuration as that of the rubber composition 1 except that 30 parts by mass of calcium carbonate (trade name: Shiraka Hana CC manufactured by Shiroishi Calcium Industry Co., Ltd.) is blended with 100 parts by mass of the raw rubber instead of montmorillonite. The rubber composition 21 was obtained.

(V-ribbed belt)
V-ribbed belts in which a compressed rubber layer was formed using rubber compositions 1-8 were designated as Examples 1-8, respectively. Moreover, the V ribbed belt which formed the compression rubber layer using the rubber compositions 9-21 was made into Comparative Examples 1-13, respectively.

  The adhesive rubber layer and the back rubber layer are composed of another EPDM rubber composition, the core wire is composed of a twisted yarn made of polyethylene terephthalate fiber (PET), the belt peripheral length is 1200 mm, the belt width is 21.36 mm, and the belt thickness. The thickness was 4.3 mm, and the number of ribs was six.

(Test evaluation method)
<Mass change rate>
For each of the rubber compositions 1 to 21, a test piece according to JIS K6258 was vulcanized and molded, and a test was conducted in which both sides were immersed in distilled water for 1 minute and 10 hours, and the mass change was made by a calculation method according to JIS K6258. The rate was calculated.

<Evaluation of abnormal noise when wet>
FIG. 2 shows a pulley layout of the belt running test machine 20 for evaluating abnormal noise when wet.

  The wet running noise evaluation belt running test machine 20 includes a drive pulley 21 that is a rib pulley having a pulley diameter of 140 mm, and a first driven pulley 22 that is a rib pulley having a pulley diameter of 75 mm is provided to the right of the drive pulley 21. And a second driven pulley 23, which is a rib pulley having a pulley diameter of 50 mm, is provided above the first driven pulley 22 and diagonally to the right of the drive pulley 21. Further, the drive pulley 21 and the second driven pulley An idler pulley 24, which is a flat pulley having a pulley diameter of 75 mm, is provided in the middle. In this wet running noise evaluation belt running test machine 20, the V rib side of the V-ribbed belt B is in contact with the drive pulley 21, the first and second driven pulleys 22 and 23 which are rib pulleys, and the back side is a flat pulley. It is configured to be wound around in contact with a certain idler pulley 24.

  For each of Examples 1-8 and Comparative Examples 1-13, set the belt running test machine 20 for evaluating abnormal noise when wet, positioning the pulley so that a belt tension of 49 N per rib is applied, A resistance is applied to the alternator to which the second driven pulley 23 is attached so that a current of 60 A flows, and the drive pulley 21 is rotated at a rotation speed of 800 rpm at room temperature, so that the V-ribbed belt B enters the drive pulley 21. Then, water was dropped on the V rib side of the V ribbed belt B at a rate of 1000 ml per minute. And the abnormal noise generation situation during belt running is as follows: A: No abnormal noise is generated. B: A slight noise is generated. C: An abnormal noise occurs. It was evaluated in three stages.

<Heat resistant durability evaluation>
FIG. 3 shows the pulley layout of the belt running test machine 30 for evaluating heat resistance and durability.

  In the belt running test machine 30 for evaluating heat resistance durability, a large-diameter driven pulley 31 and a driving pulley 32, which are rib pulleys each having a pulley diameter of 120 mm, are provided at intervals in the vertical direction. An idler pulley 33 that is a flat pulley having a diameter of 70 mm is provided, and a small-diameter driven pulley 34 that is a rib pulley having a pulley diameter of 55 mm is provided to the right of the idler pulley 33. In the belt running test machine 30 for evaluating heat resistance and durability, the V rib side of the V-ribbed belt B is in contact with the large-diameter driven pulley 31, the driving pulley 32, and the small-diameter driven pulley 34, which are rib pulleys, and the back side is a flat pulley. It is configured to be wound around the idler pulley 33. Each of the idler pulley 33 and the small-diameter driven pulley 34 is positioned so that the winding angle of the V-ribbed belt B is 90 °.

  About each of Examples 1-8 and Comparative Examples 1-13, it sets to the said belt running test machine 30 for heat-resistant durability evaluation, a 11.8 kW rotational load is given to the large diameter driven pulley 31, and belt tension is loaded. In this way, a dead weight of 834N was loaded laterally on the small-diameter driven pulley 34, and the driving pulley 32 was rotated at a rotational speed of 4900 rpm under an ambient temperature of 120 ° C. to run the belt. And the running time until the crack generate | occur | produced in the compression rubber layer of V ribbed belt B and it reached a cord was measured.

<Abrasion evaluation>
FIG. 4 shows a pulley layout of the belt running test machine 40 for evaluating wear.

  The wear test belt running test machine 40 includes a drive pulley 41 and a driven pulley 42 that are rib pulleys having a pulley diameter of 60 mm, which are arranged on the left and right sides. The wear evaluation belt running test machine 40 is configured such that the V rib side of the V-ribbed belt B comes into contact with the drive pulley 41 and the driven pulley 42 which are rib pulleys and is wound around.

  About each of Examples 1-8 and Comparative Examples 1-13, it set to the said belt running test machine 40 for abrasion evaluation, and while giving the rotational load of 3.82 kW to the driven pulley 42, belt tension is loaded. A dead weight of 1177 N was loaded on the side, and the belt was run for 24 hours by rotating the drive pulley 41 at 3500 rpm at room temperature. The change in belt mass obtained by subtracting the belt mass after running the belt from the belt mass before running the belt was divided by the belt mass before running the belt to calculate the wear rate.

(Test evaluation results)
The test results are shown in Tables 3 and 4.

  The rate of mass change after 1 minute of immersion was 0.35% for rubber composition 1 corresponding to Examples 1 to 8, 0.33% for rubber composition 2, 0.21% for rubber composition 3, and rubber. Composition 4 is 0.42%, rubber composition 5 is 0.43%, rubber composition 6 is 0.50%, rubber composition 7 is 0.52%, and rubber composition 8 is 0.59%. In addition, the rubber composition 9 corresponding to Comparative Examples 1 to 13 was 0.10%, the rubber composition 10 was 0.09%, the rubber composition 11 was 0.03%, and the rubber composition 12 was -0.0. 03%, rubber composition 13 is 0.01%, rubber composition 14 is -0.11%, rubber composition 15 is -0.03%, rubber composition 16 is 0.09%, and rubber composition 17 is 0.20%, rubber composition 18 is 0.22%, rubber composition 19 is 0.53%, rubber composition 20 is -0.08%, and rubber composition 21 is- It was .02%.

  The rate of mass change after the immersion time of 10 hours was 0.41% for rubber composition 1 corresponding to Examples 1 to 8, 0.46% for rubber composition 2, 0.26% for rubber composition 3, and rubber. Composition 4 is 0.45%, rubber composition 5 is 0.45%, rubber composition 6 is 0.63%, rubber composition 7 is 0.66%, and rubber composition 8 is 0.78%. Yes, the rubber composition 9 corresponding to Comparative Examples 1 to 13 was 0.25%, the rubber composition 10 was 0.15%, the rubber composition 11 was 0.23%, and the rubber composition 12 was 0.07. %, Rubber composition 13 is 0.09%, rubber composition 14 is 0.31%, rubber composition 15 is 0.56%, rubber composition 16 is 0.15%, and rubber composition 17 is 0.30%. %, Rubber composition 18 is 0.38%, rubber composition 19 is 0.80%, rubber composition 20 is 0.07%, and rubber composition 21 is 0.0%. It was%.

  As for the abnormal noise evaluation when wet, Examples 1 to 8 and Comparative Example 11 were A, Comparative Examples 1 to 7 and Comparative Example 13 were B, and Comparative Examples 8 to 10 and Comparative Example 12 were C.

  Evaluation of heat resistance was 442 hours for Example 1, 412 hours for Example 2, 420 hours for Example 3, 401 hours for Example 4, 425 hours for Example 5, 390 hours for Example 6, and 390 hours for Example 6. 7 for 418 hours and Example 8 for 283 hours, and Comparative Example 1 for 399 hours, Comparative Example 2 for 408 hours, Comparative Example 3 for 448 hours, Comparative Example 4 for 386 hours, Comparative Example 5 for 406 hours, Comparative Example 6 was 432 hours, Comparative Example 7 was 398 hours, Comparative Example 8 was 440 hours, Comparative Example 9 was 440 hours, Comparative Example 10 was 440 hours, Comparative Example 11 was 182 hours, Comparative Example 12 was 445 hours, and Comparative Example 13 was 342 hours.

  Abrasion evaluation was 1.8% in Example 1, 1.9% in Example 2, 1.8% in Example 3, 2.0% in Example 4, 1.8% in Example 5. Example 6 was 2.3%, Example 7 was 1.9%, Example 8 was 2.8%, Comparative Example 1 was 1.8%, Comparative Example 2 was 1.7%, Comparative Example 3 Is 2.0%, Comparative Example 4 is 3.2%, Comparative Example 5 is 3.8%, Comparative Example 6 is 1.8%, Comparative Example 7 is 1.9%, and Comparative Example 8 is 1.5%. Comparative Example 9 was 1.6%, Comparative Example 10 was 1.8%, Comparative Example 11 was 3.5%, Comparative Example 12 was 1.7%, and Comparative Example 13 was 2.6%.

  From the above, it can be seen that Examples 1 to 8 have a higher effect of suppressing the occurrence of abnormal noise when wet compared to Comparative Examples 1 to 13. It can also be seen that Examples 1 to 3 have the same heat resistance and durability as Comparative Examples 1 and 2.

  INDUSTRIAL APPLICABILITY The present invention is useful for a friction transmission belt in which a belt body is wound so as to contact a pulley and transmits power.

10 V-ribbed belt body 11 Compressed rubber layer 12 Adhesive rubber layer 13 Back rubber layer 14 Core wire 15 V-rib

Claims (3)

A friction transmission belt that is wound around the belt body so as to contact the pulley and transmits power;
At least the pulley contact portion of the belt main body is 30-80 of at least one layered silicate selected from smectite group, vermulite group, and kaolin group with respect to 100 parts by mass of raw rubber containing ethylene-α-olefin elastomer. A friction transmission belt characterized in that it is formed of a rubber composition blended in parts by mass. In the friction transmission belt according to claim 1,
A friction transmission belt, wherein the layered silicate contains a smectite montmorillonite. In the friction transmission belt according to claim 1 or 2,
The friction transmission belt, wherein the rubber composition forming the pulley contact portion has a mass change rate of 0.1% or more when immersed in water for 1 minute.

Images