JP2004028156A

JP2004028156A - High load transmission v-belt

Info

Publication number: JP2004028156A
Application number: JP2002182479A
Authority: JP
Inventors: Masahiro Inukai; 犬飼　雅弘; Mitsuhiko Takahashi; 高橋　光彦; Sakae Umeda; 梅田　栄; Masahide Fujita; 藤田　昌秀
Original assignee: Bando Chemical Industries Ltd; Daihatsu Motor Co Ltd
Current assignee: Bando Chemical Industries Ltd; Daihatsu Motor Co Ltd
Priority date: 2002-06-24
Filing date: 2002-06-24
Publication date: 2004-01-29
Anticipated expiration: 2022-06-24
Also published as: JP4046557B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high load transmission V-belt comprising a right and a left tension belts and many blocks engaged and fixed on each tension belt 1 capable of increasing a transmission load of the belt without increasing block weight to improve durability strength in high speed travel or high torque transmission by reducing stress concentration to roots and pillars of upper and lower beams of reinforcement members in each block. <P>SOLUTION: This high load transmission V-belt B comprises the right and the left tension belts 1 and 1, and the blocks 7 engaged and fixed on each tension belt 1. A recess 20 is formed roughly at a width center of an upper surface of the upper beam 16 of the reinforcement member 15 in the block 7. Swells 21 and 21 are formed on the upper surface of the upper beam 16 on both sides of the recess 20 to correspond to around a base end of the upper beam 16. Strength of the base end of the upper beam 16 is thus increased while restricting increase of inertial force of the block 7. An arc-shaped surface 23 is formed of a lower surface of the base end of the upper beam 16, an upper surface of a base end of the lower beam 17, and right and left side surfaces of the pillar 18, smoothly continuous roughly in arc form. Stress concentration to the base ends of the upper and the lower beams 16 and 17 is thus avoided, thereby durability strength of the belt B is improved. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、高負荷伝動用Ｖベルトに関し、特に、そのブロックにおける補強部材の強度を高めるための対策に関する技術分野に属する。
【０００２】
【従来の技術】
従来より、多数のブロックと心線及び硬質ゴムからなる張力帯とで構成され、張力帯と各ブロックとの動力授受をブロックと張力帯との係合により行う形式の高負荷伝動用Ｖベルトは知られている。このＶベルトでは、その曲易さを確保するために、各ブロックの張力帯への固定を接着ではなく、物理的な係合状態（噛合状態）により行うようになされている。
【０００３】
ところで、このような高負荷伝動用Ｖベルトでは、その各ブロックを硬質樹脂材料で形成し、その内部に補強のための補強部材が少なくとも張力帯との噛合部及びプーリ溝面との接触部を樹脂部とするように埋設され、この補強部材は張力帯の上下側にそれぞれ位置する上下側ビーム部と、これら上下ビーム部の基端部同士を接続するピラー部とからなっている。
【０００４】
しかし、このベルトによる高負荷伝動時、上記ブロック内の補強部材のうち、張力帯の上側（プーリの半径方向外側）に位置する上ビーム部の基端部（根元部）に繰返し応力が作用すると、その上ビーム部が根元部分から折損することがあり、ベルトによる動力伝達が不可能になる。
【０００５】
そこで、従来、実開平５―３６９２号公報に示されるように、上記ブロックの補強部材においてベルト幅方向に延びる左右の上ビーム部を全体中央部の位置が左右両端部よりも高くなるようにアーチ形状に湾曲させることにより、上ビーム部の根元部に発生する応力を小さくしてその折損を防止することが提案されている。
【０００６】
また、この他、特開２０００―１２０７９６号公報に示されるように、各ブロックにおける補強部材の上側ビーム部を、基端部側の上下中心線とブロックの上側接触部の接触位置よりもプーリ中心側のプーリ溝面とのなすビーム角が９０°以上となる一方、先端部側の上下中心線とブロック側面の上側接触部の接触位置よりもプーリ中心側のプーリ溝面とのなすビーム角が９０°よりも小さくなるように曲がった形状とする（各ブロックにおける補強部材の上側ビーム部の上下中心線と、ブロック側面の上側接触部の接触位置よりもプーリ中心側のプーリ溝面とのなすビーム角を９０°以上とする）ことにより、上側ビーム部の先端部がプーリ溝面からの反力上側に押されることにより生じる曲げモーメントを抑制することが提案されている。
【０００７】
【発明が解決しようとする課題】
しかし、これらの提案例のものにおいては、ベルトの高速走行時或いは高トルク伝動時（低速高負荷時）に、ブロックにおける補強部材の上下ビーム部の各基端部下面とピラー部の左右側面との境界部分に応力集中が生じて、これらの箇所で補強部材が破断し易く、ブロック延いてはベルトの耐久強度が不十分となり、さらなる改良の余地があった。
【０００８】
本発明は斯かる点に鑑みてなされたもので、その目的は、ブロックの補強部材の形状を適正に変えることにより、その上下ビーム部の根元部分やピラー部にかかる応力集中を減少させ、ブロック重量の増加を招くことなくベルトの伝動負荷をさらに増大させて、ベルトの高速走行時や高トルク伝動時の耐久強度を向上させることにある。
【０００９】
【課題を解決するための手段】
上記の目的を達成するために、請求項１の発明では、上下面にそれぞれベルト長さ方向に並ぶ多数の上側被噛合部及び下側被噛合部が上下に対応して設けられた左右１対の張力帯と、ベルト幅方向の左右側面に、上壁面に上記各張力帯の上側被噛合部に噛合する上側噛合部を有する一方、下壁面に張力帯の下側被噛合部に噛合する下側噛合部を有する嵌合溝が設けられ、この嵌合溝の上下両側の側面にそれぞれプーリ溝面に接触する上側及び下側接触部が設けられた多数のブロックとを備え、この各ブロックの嵌合溝に張力帯を嵌合することにより、各ブロックが張力帯に係合固定され、上記各ブロックは、樹脂部内に少なくとも上記上下の噛合部及び接触部が樹脂部で構成されるように埋設された補強部材を備え、この補強部材は、先端側が上記嵌合溝の上側及び下側にそれぞれ位置する上下ビーム部と、該上下ビーム部の左右中央の基端部同士を接続するピラー部とからなる高負荷伝動用Ｖベルトが対象である。
【００１０】
そして、上記補強部材の上ビーム部上面の左右略中央部には凹陥部がピラー部の略真上に対応するように形成され、上記凹陥部の左右両側の上ビーム部上面には、上側に膨出する膨出部が凹陥部に隣接しかつ上ビーム部の基端部付近に対応するように形成されていることを特徴としている。
【００１１】
上記の構成によると、ブロックにおける補強部材の上ビーム部上面に、上側に膨出する膨出部が上ビーム部の基端部付近に対応して形成されているので、その上ビーム部が基端部から先端側に向かって略一定の上下幅に設定されている場合に比べ、上ビーム部の基端部の上下幅が先端側よりも増大して該基端部の強度が大きくなり、このことにより、ベルトの高速走行時や高トルク伝動時（低速高負荷時）に、上ビーム部の基端部が破断するのを抑制することができる。
【００１２】
また、上記補強部材の上ビーム部上面の左右略中央部、つまり上記左右の膨出部間に隣接して挟まれた位置は、上ビーム部の基端部の強度増大に対する寄与が小さく、この部分に凹陥部が形成されているので、この凹陥部の分だけ上ビーム部の上下幅、従って質量が小さくなり、ベルトのプーリ回りの高速走行時のブロックの慣性力の増加を抑えて、プーリに対する入力荷重の増加を小さくすることができる。
【００１３】
請求項２の発明では、上記請求項１の発明の対象と同様の高負荷伝動用Ｖベルトに対し、そのブロックの補強部材の上ビーム部基端部下面と、下ビーム部基端部上面と、ピラー部の左右側面とが略円弧形状に滑らかに連続した円弧状面を形成していることを特徴とする。
【００１４】
こうすれば、補強部材の上ビーム部基端部下面とピラー部の左右側面との境界部分、及び下ビーム部基端部上面とピラー部の左右側面との境界部分の各円弧半径を可及的に大きくして、それら補強部材の上ビーム部基端部及び下ビーム部基端部に対する応力の集中を回避することができ、上下ビーム部の各基端部が破断するのを抑制することができる。
【００１５】
請求項３の発明では、上記請求項１の高負荷伝動用Ｖベルトにおいて、ブロックの補強部材の上ビーム部基端部下面と、下ビーム部基端部上面と、ピラー部の左右側面とが略円弧形状に滑らかに連続している構成とする。このことで、上記請求項１及び２の発明の作用効果が相乗的に得られ、上下ビーム部の各基端部の破断をさらに有効に抑制することができる。
【００１６】
その場合、請求項４の発明では、上記請求項２又は３の高負荷伝動用Ｖベルトにおいて、上記円弧状面における上ビーム部基端部下面とピラー部の左右側面との境界部分、及び下ビーム部基端部上面とピラー部の左右側面との境界部分の半径は、円弧状面の上下方向の内径の０．３〜０．５とする。こうすると、上ビーム部基端部下面及び下ビーム部基端部上面とピラー部の左右側面との境界部分の望ましい円弧半径が得られる。
【００１７】
請求項５の発明では、上記請求項１の発明の対象と同様の高負荷伝動用Ｖベルトに対し、そのブロックの補強部材の下ビーム部は、その先端側に向かうに連れて上側に向かった後に下側に向かうように湾曲している構造とする。このことで、下ビーム部の剛性を高めることができるとともに、下ビーム部下面の先端側を上側に凹陥させて下ビーム部の上下幅つまり質量を小さくでき、ベルトのプーリ回りの高速走行時のブロックの慣性力の増加を抑えて、プーリに対する入力荷重の増加を小さくすることができる。さらに、下ビーム部の湾曲により、その下ビーム部基端部上面の円弧半径を可及的に大きくして下ビーム部基端部に対する応力の集中を回避し、下ビーム部の基端部が破断するのを抑制することができる。
【００１８】
【発明の実施の形態】
図４は本発明の実施形態に係る高負荷伝動用ＶベルトＢを示し、このベルトＢは、左右１対のエンドレスの張力帯１，１と、この張力帯１，１にベルト長手方向に連続的に係合固定された多数のブロック７，７，…とからなる。
【００１９】
上記各張力帯１は、硬質ゴムからなる保形層１ａの内部に、ベルトＢの伸びを抑えるためにアラミド繊維等の高強度高弾性率の複数の心線１ｂ，１ｂ，…（心体）がスパイラルに配置されて埋設されたもので、この各張力帯１の上面には各ブロック７に対応してベルト幅方向に延びる一定ピッチの上側被噛合部としての溝状の上側凹部２，２，…が、また下面には上記上側凹部２，２，…に対応してベルト幅方向に延びる一定ピッチの下側被噛合部としての下側凹部３，３，…がそれぞれ形成されている。張力帯１の上下表面には、その耐摩耗性を向上させる等の目的で帆布４，４が積層一体化されている。
【００２０】
上記保形層１ａをなす硬質ゴムは、例えばメタクリル酸亜鉛によりを強化されたＨ−ＮＢＲゴムに、さらにアラミド繊維、ナイロン繊維等の短繊維により強化することで、耐熱性に優れかつ永久変形し難い硬質ゴムが用いられる。この硬質ゴムの硬さは、ＪＩＳ−Ｃ硬度計で測定したときに７５°以上のゴム硬度が必要である。
【００２１】
一方、上記各ブロック７は、ベルト幅方向左右側面に上記各張力帯１を幅方向から着脱可能に嵌装せしめる切欠き状の嵌合溝８，８を有する。この各嵌合溝８を除いた上下両側の左右側面は、Ｖプーリからなる変速プーリＰ（定速プーリでもよい）のプーリ溝面Ｐ１に当接する上側及び下側接触部１１，１１に構成され、このブロック７の左右の接触部１１，１１同士がなすベルト角度は、プーリＰの左右のプーリ溝面Ｐ１，Ｐ１間の角度と同じとされている。そして、各ブロック７は、ベルト幅方向（左右方向）に延びる上側及び下側ビーム７ａ，７ｂと、該両ビーム７ａ，７ｂの左右中央部同士を上下に接続するピラー７ｃとからなる略Ｈ字状のものに形成されており、各ブロック７の嵌合溝８，８にそれぞれ張力帯１，１を圧入して嵌合することで、ブロック７，７，…が張力帯１，１にベルト長手方向に連続的に一定のピッチで固定されている。
【００２２】
すなわち、上記各ブロック７における各嵌合溝８の上壁面には上記張力帯１上面の各上側凹部２に噛合する上側噛合部としての凸条からなる上側凸部９が、また嵌合溝８の下壁面には張力帯１下面の各下側凹部３に噛合する下側噛合部としての凸条からなる下側凸部１０がそれぞれ互いに平行に配置されて形成されており、この各ブロック７の上下の凸部９，１０をそれぞれ張力帯１の上下の凹部２，３に噛合せしめることで、ブロック７，７，…を張力帯１，１にベルト長手方向に圧入により係合固定し、この係合状態で各張力帯１の外側側面と各ブロック７の左右側面である接触部１１，１１との双方がプーリ溝面Ｐ１に接触するようになされている（尚、各張力帯１の外側側面は必ずしもプーリ溝面Ｐ１に接触させる必要はない）。
【００２３】
図２及び図３に示す如く、上記各ブロック７は、フェノール樹脂等の硬質樹脂材料からなる樹脂部１４を有し、この樹脂部１４の内部には、硬質樹脂よりも高い弾性率材料である軽量アルミニウム合金等からなる補強部材１５がブロック７の略中央に位置するように埋設されている。この補強部材１５は、例えばブロック７の上下の凸部９，１０（張力帯１との噛合部）を含む嵌合溝８の周囲部分と、左右側面にある接触部１１，１１と、ブロック７上面の左右中央部とにおいて硬質樹脂部１４中に埋め込まれてブロック７表面に顕れていないが（つまり、これらの部分は樹脂部１４の硬質樹脂材料で構成されている）、その他の部分ではブロック７表面に露出している（尚、補強部材１５の全体が樹脂部１４から露出されないように、つまり補強部材１５全体を樹脂部１４内に完全に埋め込むようにすることもできる）。
【００２４】
図１に示すように、上記補強部材１５は、ベルト幅方向（左右方向）に延びかつ先端側が上記各嵌合溝８の上下側にそれぞれ位置する上ビーム部１６及び下ビーム部１７と、これら上ビーム部１６の基端部及び下ビーム部１７の基端部同士を上下に一体に接続するピラー部１８とからなっていて、略Ｈ字状に形成されている。
【００２５】
そして、予め、上記硬質ゴムからなる張力帯１の上下の凹部２，３間の噛合厚さ、つまり上側凹部２の底面（詳しくは上側帆布４の上表面）と該上側凹部２に対応する下側凹部３の底面（同下側帆布４の下表面）との間の距離が、ブロック７の噛合隙間、つまり各ブロック７の上側凸部９下端と下側凸部１０上端との間の距離よりも例えば０．０３〜０．１５ｍｍ程度だけ若干大きく設定されており、各ブロック７の張力帯１への組付時に張力帯１がブロック７により厚さ方向に圧縮されて組み付けられ、このことで初期締め代（ブロック７に対する張力帯１の初期圧入代）が設けられている。
【００２６】
また、上記各ブロック７の略下半部、つまりブロック７の上下中央部から下端部までの部分は、ベルト長さ方向に沿った寸法である厚さが下端に向かって次第に小さくなるように所定のテーパ角で傾斜した先細りテーパ状に形成されており、プーリＰにＶベルトＢが巻き付けられたときに、隣接するブロック７，７の下端部同士が互いに接触により干渉しないようになっている。
【００２７】
本発明の特徴は、上記各ブロック７における補強部材１５にある。すなわち、補強部材１５の上記上ビーム部１６上面の左右略中央部には、下側に凹陥した凹陥部２０がピラー部１８の略真上に対応するように形成されている。また、この凹陥部２０の左右両側の上ビーム部１６上面には凹陥部２０に隣接した位置に、上側に円弧状に膨出する左右１対の膨出部２１，２１（山部）が上ビーム部１６の基端部付近に対応するように形成されている。
【００２８】
また、補強部材１５の下ビーム部１７は、その先端側に向かうに連れて上側に向かった後に下側に向かうように、換言すれば先端側の中間部が上側に膨出するように湾曲している。
【００２９】
そして、上記上ビーム部１６基端部下面と、下ビーム部１７基端部上面と、ピラー部１８の左右側面とは略円弧形状に滑らかに連続した円弧状面２３を形成しており（図１では円形状を仮想線にて示している）、この円弧状面２３における上ビーム部１６基端部下面とピラー部１８の左右側面との境界部分２４の半径Ｒｕ、及び下ビーム部１７基端部上面とピラー部１８の左右側面との境界部分２５の半径Ｒｄは、円弧状面２３の上下方向の径Ｄの０．３〜０．５（Ｒｕ＝０．３〜０．５Ｄ、Ｒｄ＝０．３〜０．５Ｄ）、つまり０．３以上でかつ０．５以下とされている。この値が０．３よりも小さいときには、当該境界部分２４，２５に応力が集中して著しい早期破損に繋がる一方、０．５よりも大きいときには、上ビーム部１６と下ビーム部１７との根本部分の曲率が相対的に小さくなり、この部分への応力集中が顕著となる。
【００３０】
したがって、この実施形態においては、ベルトＢの各ブロック７に埋め込まれている補強部材１５のうち、その上ビーム部１６上面に、上側に膨出する左右の膨出部２１，２１が上ビーム部１６の基端部付近に対応して形成されているので、その上ビーム部が基端部から先端側に向かって略一定の上下幅に設定されている場合に比べ、上ビーム部１６の基端部の上下幅が先端側よりも増大して該基端部の強度が大きくなり、このことにより、ベルトＢの高速走行時や高トルク伝動時（低速高負荷時）に、上ビーム部１６の基端部が破断するのを抑制することができる。
【００３１】
また、上記上ビーム部１６上面の左右略中央部、つまり上記左右の膨出部２１，２１間に隣接して挟まれた位置は、上ビーム部１６の基端部の強度増大に対する寄与が小さい部分であり、この部分に凹陥部２０が形成されているので、この凹陥部２０の分だけ上ビーム部１６の上下幅、従って質量が小さくなり、ベルトＢのプーリＰ回りの高速走行時のブロック７の慣性力の増加を抑えて、プーリＰに対する入力荷重の増加を小さくすることができる。
【００３２】
さらに、各ブロック７の補強部材１５の上ビーム部１６基端部下面と、下ビーム部１７基端部上面と、ピラー部１８の左右側面とが略円弧形状に滑らかに連続した円弧状面２３を形成しているので、補強部材１５の上ビーム部１６基端部下面とピラー部１８の左右側面との境界部分２４の円弧半径Ｒｕ、及び下ビーム部１７基端部上面とピラー部１８の左右側面との境界部分２５の円弧半径Ｒｄをいずれも可及的に大きくして、それら補強部材１５の上ビーム部１６基端部及び下ビーム部１７基端部に対する応力の集中を回避することができ、上下ビーム部１６，１７の各基端部が破断するのを抑制することができる。
【００３３】
さらにまた、上記補強部材１５の下ビーム部１７は、その先端側に向かう中間部を上側に膨出させるように湾曲しているので、下ビーム部１７の剛性を高めることができるとともに、下ビーム部１７下面の先端側を上側に凹陥させて下ビーム部１７の上下幅、つまり質量を小さくでき、ベルトＢのプーリＰ回りの高速走行時のブロック７の慣性力の増加を抑えて、プーリＰに対する入力荷重の増加を小さくすることができる。さらに、下ビーム部１７の湾曲により、その下ビーム部１７基端部上面の円弧半径を可及的に大きくして下ビーム部１７基端部に対する応力の集中を回避し、下ビーム部１７の基端部が破断するのを抑制することができる。
【００３４】
尚、上記実施形態では、（ア）補強部材１５の上ビーム部１６上面に凹陥部２０及び膨出部２１，２１が形成されていること、（イ）下ビーム部１７の先端側が湾曲していること、（ウ）上ビーム部１６基端部下面と、下ビーム部１７基端部上面と、ピラー部１８の左右側面とが略円弧形状に滑らかに連続した円弧状面２３を形成していることを全て満たすようになっているが、本発明は上記（ア）〜（ウ）の少なくとも１つを満たすようにすればよく、上記説明したのと同様の作用効果が得られる。
【００３５】
また、上記実施形態では、張力帯１の上面に被噛合部としての上側凹部２を、また各ブロック７の嵌合溝８の上面に上記張力帯１の上側凹部２に噛合する噛合部としての上側凸部９をそれぞれ形成しているが、その他、例えば張力帯１の上面に被噛合部としての上側凸部を、また各ブロック７の嵌合溝８の上面に張力帯１上面の上側凸部に噛合する噛合部としての上側凹部をそれぞれ設けてもよい。さらに、張力帯１の下面に被噛合部としての下側凸部を、また各ブロック７の嵌合溝８の下面に張力帯１下面の下側凸部に噛合する噛合部としての下側凹部をそれぞれ設けることもできる。
【００３６】
【発明の効果】
以上説明したように、請求項１の発明によると、張力帯と、この張力帯に噛合状態により係合固定された多数のブロックとからなる高負荷伝動用Ｖベルトにおいて、そのブロックの樹脂部内に埋設されている補強部材の上ビーム部上面の左右略中央部に凹陥部を形成し、この凹陥部の左右両側の上ビーム部上面で凹陥部に隣接した位置に、上側に膨出する膨出部を上ビーム部の基端部付近に対応するように形成したことにより、ベルトのプーリ回りの高速走行時のブロックの慣性力の増加を抑えてプーリに対する入力荷重の増加を小さくしながら、上ビーム部の基端部の強度を大きくして、ベルトの高速走行時や高トルク伝動時（低速高負荷時）に上ビーム部の基端部が破断するのを抑制し、高負荷伝動用Ｖベルトの耐久強度の向上を図ることができる。
【００３７】
請求項２、３又は４の発明によると、ブロックの補強部材の上ビーム部基端部下面と、下ビーム部基端部上面と、ピラー部の左右側面とが略円弧形状に滑らかに連続した円弧状面を形成するようにしたことにより、補強部材の上ビーム部基端部下面及び下ビーム部基端部上面とピラー部の左右側面との境界部分の円弧半径を可及的に大きくし、上下ビーム部基端部に対する応力の集中を回避して上下ビーム部の各基端部が破断するのを抑制でき、高負荷伝動用Ｖベルトの耐久強度の向上を図ることができる。
【００３８】
請求項５の発明によると、ブロックの補強部材の下ビーム部を、その先端側に向かうに連れて上側に向かった後に下側に向かうように湾曲した構造としたことにより、下ビーム部の剛性を高めることができるとともに、下ビーム部の質量を小さくしてベルトのプーリ回りの高速走行時のブロックの慣性力の増加を抑え、プーリに対する入力荷重の増加を小さくすることができ、さらには下ビーム部基端部上面の円弧半径を可及的に大きくして下ビーム部基端部に対する応力の集中を回避し、下ビーム部の基端部が破断するのを抑制して、高負荷伝動用Ｖベルトの耐久強度の向上を図ることができる。
【図面の簡単な説明】
【図１】補強部材の拡大正面図である。
【図２】ブロックの拡大正面図である。
【図３】ブロックの厚さ方向中央にて切断した状態のベルトの拡大断面図である。
【図４】本発明の実施形態に係る高負荷伝動用Ｖベルトの斜視図である。
【符号の説明】
Ｂ　高負荷伝動用Ｖベルト
１　張力帯
２　上側凹部（上側被噛合部）
３　下側凹部（下側被噛合部）
７　ブロック
８　嵌合溝
９　上側凸部（上側噛合部）
１０　下側凸部（下側噛合部）
１１　接触部
１４　樹脂部
１５　補強部材
１６　上ビーム部
１７　下ビーム部
１８　ピラー部
２０　凹陥部
２１　膨出部
２３　円弧状面
２４　上ビーム部基端部下面とピラー部の左右側面との境界部分
２５　下ビーム部基端部上面とピラー部の左右側面との境界部分
Ｒｕ　上ビーム部基端部下面とピラー部の左右側面との境界部分の半径
Ｒｄ　下ビーム部基端部上面とピラー部の左右側面との境界部分の半径
Ｄ　円弧状面の上下方向の径
Ｐ　変速プーリ
Ｐ１　プーリ溝面[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a high-load transmission V-belt, and particularly to a technical field related to a measure for increasing the strength of a reinforcing member in a block thereof.
[0002]
[Prior art]
2. Description of the Related Art A high-load transmission V-belt of a type that includes a large number of blocks and a tension band made of a core wire and a hard rubber, and transfers power between the tension band and each block by engaging the block with the tension band is known. Are known. In this V-belt, each block is fixed to the tension band in a physically engaged state (engaged state), not by adhesion, in order to ensure its flexibility.
[0003]
By the way, in such a high-load transmission V-belt, each block is formed of a hard resin material, and a reinforcing member for reinforcement has at least a meshing portion with a tension band and a contacting portion with a pulley groove surface. The reinforcing member is buried so as to be a resin portion, and the reinforcing member includes upper and lower beam portions respectively located on the upper and lower sides of the tension band, and pillar portions connecting base ends of the upper and lower beam portions.
[0004]
However, at the time of high-load transmission by this belt, if a repetitive stress acts on the base end portion (root portion) of the upper beam portion located above the tension band (radially outside the pulley) of the reinforcing members in the block. However, the upper beam portion may be broken from the root portion, and power transmission by the belt becomes impossible.
[0005]
Therefore, conventionally, as shown in Japanese Utility Model Laid-Open No. 5-3692, the upper and lower beam portions extending in the belt width direction of the reinforcing member of the block are arched so that the position of the entire central portion is higher than the left and right end portions. It has been proposed to reduce the stress generated at the root portion of the upper beam portion to prevent the upper beam portion from being broken by bending it into a shape.
[0006]
In addition, as shown in Japanese Patent Application Laid-Open No. 2000-120796, the upper beam portion of the reinforcing member in each block is set at a position closer to the pulley center than the contact position between the vertical center line on the base end side and the upper contact portion of the block. The beam angle between the pulley groove surface on the side of the pulley is 90 ° or more, and the beam angle between the pulley groove surface on the center side of the pulley and the contact position of the upper and lower center lines on the tip side and the upper contact portion on the side surface of the block. (Between the vertical center line of the upper beam portion of the reinforcing member in each block and the pulley groove surface closer to the center of the pulley than the contact position of the upper contact portion on the side surface of the block.) By setting the beam angle to 90 ° or more), it is proposed to suppress the bending moment caused by the tip of the upper beam portion being pushed upward by the reaction force from the pulley groove surface.
[0007]
[Problems to be solved by the invention]
However, in these proposals, when the belt is running at high speed or when transmitting high torque (at low speed and high load), the lower surface of each base end of the upper and lower beam portions of the reinforcing member in the block and the left and right side surfaces of the pillar portion The stress concentration occurs at the boundary portion of, and the reinforcing member is easily broken at these locations, and the durability of the block and the belt becomes insufficient, and there is room for further improvement.
[0008]
The present invention has been made in view of such a point, and an object of the present invention is to appropriately change the shape of a reinforcing member of a block to reduce the concentration of stress applied to a root portion and a pillar portion of the upper and lower beam parts, An object of the present invention is to further increase the durability of the belt when the belt is running at high speed or when transmitting high torque, by further increasing the transmission load of the belt without increasing the weight.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, a pair of left and right upper and lower meshed portions are provided on the upper and lower surfaces corresponding to the upper and lower portions, respectively. On the left and right side surfaces in the belt width direction, the upper wall has an upper meshing portion that meshes with the upper meshed portion of each tension band, while the lower wall has a lower meshing portion that meshes with the lower meshed portion of the tension band. A plurality of blocks provided with a fitting groove having a side meshing portion, and upper and lower contact portions respectively contacting the pulley groove surfaces are provided on upper and lower side surfaces of the fitting groove. By fitting the tension band into the fitting groove, each block is engaged and fixed to the tension band, and each block is configured such that at least the upper and lower meshing portions and contact portions are formed of a resin portion in a resin portion. A buried reinforcing member, wherein the reinforcing member Upper and lower beam portion and the high-load drive V-belt comprising a pillar portion connecting the left-right center of the base end portions of the upper and lower beam portions respectively positioned above and below the above-mentioned fitting groove is subject.
[0010]
A concave portion is formed substantially at the center of the upper surface of the upper beam portion of the reinforcing member on the right and left sides so as to correspond to substantially right above the pillar portion. The bulging portion is formed so as to be adjacent to the concave portion and correspond to the vicinity of the base end of the upper beam portion.
[0011]
According to the above configuration, the swelling portion bulging upward is formed on the upper surface of the upper beam portion of the reinforcing member in the block corresponding to the vicinity of the base end of the upper beam portion. Compared to the case where the vertical width is set to be substantially constant from the end toward the distal end, the vertical width of the proximal end of the upper beam portion is larger than that of the distal end, and the strength of the proximal end is increased, Thus, it is possible to prevent the base end of the upper beam portion from being broken at the time of high-speed running of the belt or at the time of high-torque transmission (at low-speed and high-load).
[0012]
In addition, the left and right substantially central portions of the upper surface of the upper beam portion of the reinforcing member, that is, positions sandwiched between the left and right bulging portions have a small contribution to increasing the strength of the base end portion of the upper beam portion. Since the concave portion is formed in the portion, the vertical width of the upper beam portion, and therefore the mass, is reduced by the amount of the concave portion, and the increase in the inertial force of the block at high speed traveling around the belt pulley is suppressed, and the pulley The increase in the input load to the can be reduced.
[0013]
According to the second aspect of the present invention, for the high load transmission V-belt similar to the object of the first aspect of the present invention, the lower end of the upper beam portion and the upper surface of the lower end portion of the reinforcing member of the block are provided. The left and right side surfaces of the pillar portion form an arc-shaped surface that is smoothly continuous in a substantially arc shape.
[0014]
In this case, the arc radii of the boundary between the lower surface of the upper end portion of the reinforcing member and the right and left side surfaces of the pillar portion and the boundary portion between the upper surface of the lower end portion of the lower beam portion and the left and right side surfaces of the pillar portion can be as large as possible. It is possible to avoid concentration of stress on the upper beam base end and the lower beam base of these reinforcing members, and to suppress breakage of each base of the upper and lower beam parts. Can be.
[0015]
According to a third aspect of the present invention, in the high load transmission V-belt of the first aspect, the lower surface of the upper end portion of the upper beam portion, the upper surface of the lower end portion of the lower beam portion, and the left and right side surfaces of the pillar portion are provided. The configuration is such that it is smoothly continuous in a substantially arc shape. Thus, the effects of the first and second aspects of the present invention are synergistically obtained, and breakage of each base end of the upper and lower beam portions can be more effectively suppressed.
[0016]
In this case, according to the invention of claim 4, in the high-load transmission V-belt of claim 2 or 3, the boundary between the lower surface of the base end portion of the upper beam portion and the left and right side surfaces of the pillar portion on the arcuate surface and the lower portion. The radius of the boundary between the upper surface of the base end portion of the beam portion and the left and right side surfaces of the pillar portion is 0.3 to 0.5, which is the inner diameter of the arc-shaped surface in the vertical direction. In this way, a desired arc radius at the boundary between the lower surface of the upper end portion of the upper beam portion and the upper surface of the lower end portion of the lower beam portion and the left and right side surfaces of the pillar portion can be obtained.
[0017]
According to the fifth aspect of the present invention, with respect to the high load transmission V-belt similar to the object of the first aspect of the present invention, the lower beam portion of the reinforcing member of the block is directed upward toward the distal end. Later, the structure is curved downward. As a result, the rigidity of the lower beam portion can be increased, and the lower end of the lower beam portion can be recessed upward to reduce the vertical width or mass of the lower beam portion. The increase in the inertial force of the block can be suppressed, and the increase in the input load to the pulley can be reduced. In addition, due to the curvature of the lower beam portion, the arc radius of the upper surface of the lower beam portion base end portion is made as large as possible to avoid concentration of stress on the lower beam portion base end portion, and the lower beam portion has a base end portion. Breaking can be suppressed.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 4 shows a V-belt B for high-load transmission according to an embodiment of the present invention. The belt B has a pair of left and right endless tension bands 1 and 1 and is continuous with the tension bands 1 and 1 in the belt longitudinal direction. , And a plurality of blocks 7, 7,...
[0019]
Each of the tension belts 1 has a plurality of high-strength and high-modulus core wires 1b, 1b,... (Core body), such as aramid fibers, inside a shape-retaining layer 1a made of hard rubber to suppress the elongation of the belt B. Are arranged spirally and buried. On the upper surface of each tension band 1, groove-shaped upper concave portions 2, 2 serving as upper meshed portions having a constant pitch and extending in the belt width direction corresponding to the respective blocks 7. Are formed on the lower surface of the lower concave portions 3, 3,... Corresponding to the upper concave portions 2, 2,. On the upper and lower surfaces of the tension band 1, canvases 4 and 4 are laminated and integrated for the purpose of improving the wear resistance and the like.
[0020]
The hard rubber forming the shape-retaining layer 1a is excellent in heat resistance and is permanently deformed by, for example, reinforcing H-NBR rubber reinforced with zinc methacrylate with short fibers such as aramid fiber and nylon fiber. Hard rubber that is difficult to use is used. The hardness of the hard rubber requires a rubber hardness of 75 ° or more when measured with a JIS-C hardness tester.
[0021]
On the other hand, each of the blocks 7 has notch-shaped fitting grooves 8, 8 on the left and right side surfaces in the belt width direction for detachably fitting the tension bands 1 from the width direction. The left and right sides of the upper and lower sides excluding the respective fitting grooves 8 are formed as upper and lower contact portions 11, 11 which abut against the pulley groove surface P1 of the speed change pulley P (which may be a constant speed pulley) composed of a V pulley. The belt angle formed between the left and right contact portions 11 of the block 7 is the same as the angle between the left and right pulley groove surfaces P1 and P1 of the pulley P. Each block 7 has an approximately H-shape including upper and lower beams 7a, 7b extending in the belt width direction (left-right direction) and pillars 7c connecting the left and right central portions of both beams 7a, 7b to each other up and down. Are fitted into the fitting grooves 8, 8 of each block 7 by press-fitting and fitting the tension bands 1, 1, respectively, so that the blocks 7, 7,. It is fixed at a constant pitch continuously in the longitudinal direction.
[0022]
That is, on the upper wall surface of each fitting groove 8 in each block 7, there is provided an upper convex portion 9 made of a ridge as an upper meshing portion meshing with each upper concave portion 2 on the upper surface of the tension band 1. On the lower wall surface of the lower surface of the tension band 1, there are formed lower protrusions 10 each of which is formed in parallel with each other and is formed in parallel with each other. Are engaged with the upper and lower concave portions 2 and 3 of the tension band 1 to press-fit the blocks 7, 7,. In this engagement state, both the outer side surface of each tension band 1 and the contact portions 11, 11 which are the left and right side surfaces of each block 7 are brought into contact with the pulley groove surface P1 (note that each tension band 1 has The outer side surface does not necessarily need to contact the pulley groove surface P1).
[0023]
As shown in FIGS. 2 and 3, each of the blocks 7 has a resin portion 14 made of a hard resin material such as a phenol resin, and inside the resin portion 14 is a material having a higher elastic modulus than the hard resin. A reinforcing member 15 made of a lightweight aluminum alloy or the like is embedded so as to be located substantially at the center of the block 7. The reinforcing member 15 includes, for example, a peripheral portion of a fitting groove 8 including upper and lower convex portions 9 and 10 (a mesh portion with the tension band 1) of the block 7, contact portions 11 and 11 on left and right side surfaces, and a block 7. Although it is embedded in the hard resin portion 14 at the left and right central portions of the upper surface and is not visible on the surface of the block 7 (that is, these portions are made of the hard resin material of the resin portion 14), the other portions are blocks. 7 is exposed on the surface (note that the entire reinforcing member 15 is not exposed from the resin portion 14, that is, the entire reinforcing member 15 can be completely embedded in the resin portion 14).
[0024]
As shown in FIG. 1, the reinforcing member 15 includes an upper beam portion 16 and a lower beam portion 17 which extend in a belt width direction (lateral direction) and whose leading ends are respectively located above and below the fitting grooves 8. A pillar portion 18 connects the base end of the upper beam portion 16 and the base end of the lower beam portion 17 together vertically, and is formed in a substantially H shape.
[0025]
The mesh thickness between the upper and lower concave portions 2 and 3 of the tension band 1 made of the hard rubber, that is, the bottom surface of the upper concave portion 2 (specifically, the upper surface of the upper canvas 4) and the lower portion corresponding to the upper concave portion 2 are previously determined. The distance between the bottom of the side recess 3 (the lower surface of the lower canvas 4) is the mesh gap of the blocks 7, that is, the distance between the lower end of the upper protrusion 9 and the upper end of the lower protrusion 10 of each block 7. For example, the tension band 1 is set to be slightly larger than the tension band 1 by about 0.03 to 0.15 mm, and when the blocks 7 are assembled to the tension band 1, the tension bands 1 are compressed in the thickness direction by the blocks 7 and assembled. , An initial tightening allowance (initial press-fit allowance of the tension band 1 to the block 7) is provided.
[0026]
The lower half of each block 7, that is, the portion from the upper and lower center to the lower end of the block 7, has a predetermined thickness such that the thickness along the belt length direction gradually decreases toward the lower end. When the V-belt B is wound around the pulley P, the lower ends of the adjacent blocks 7, 7 do not interfere with each other when the V-belt B is wound around the pulley P.
[0027]
The feature of the present invention resides in the reinforcing member 15 in each block 7 described above. That is, a recess 20 that is recessed downward is formed substantially at the center of the upper surface of the upper beam portion 16 in the left and right direction of the reinforcing member 15 so as to correspond to substantially directly above the pillar portion 18. On the upper surface of the upper beam portion 16 on both the left and right sides of the concave portion 20, a pair of left and right bulges 21, 21 (peaks) bulging upward in an arc shape are located at positions adjacent to the concave portion 20. It is formed so as to correspond to the vicinity of the base end of the beam portion 16.
[0028]
In addition, the lower beam portion 17 of the reinforcing member 15 is curved so as to go upward as it goes toward its distal end and then downward, in other words, so that the intermediate portion at the distal end swells upward. ing.
[0029]
The lower surface of the upper end portion of the upper beam portion 16, the upper surface of the lower end portion of the lower beam portion 17, and the left and right side surfaces of the pillar portion 18 form an arcuate surface 23 that is smoothly continuous in a substantially arcuate shape (FIG. 1, a circular shape is shown by a virtual line), a radius Ru of a boundary portion 24 between the lower surface of the base end portion of the upper beam portion 16 and the left and right side surfaces of the pillar portion 18 in the arcuate surface 23, and a lower beam portion 17 The radius Rd of the boundary portion 25 between the upper surface of the end portion and the left and right side surfaces of the pillar portion 18 is 0.3 to 0.5 (Ru = 0.3 to 0.5D, Rd) of the vertical diameter D of the arcuate surface 23. = 0.3 to 0.5D), that is, 0.3 or more and 0.5 or less. When this value is smaller than 0.3, stress concentrates on the boundary portions 24 and 25, leading to remarkable premature failure. On the other hand, when it is larger than 0.5, the root between the upper beam portion 16 and the lower beam portion 17 is damaged. The curvature of the portion becomes relatively small, and the stress concentration on this portion becomes significant.
[0030]
Therefore, in this embodiment, of the reinforcing members 15 embedded in each block 7 of the belt B, the left and right swelling portions 21 and 21 swelling upward are formed on the upper surface of the upper beam portion 16. 16 is formed corresponding to the vicinity of the base end portion of the upper beam portion 16 as compared with the case where the upper beam portion is set to a substantially constant vertical width from the base end portion to the distal end side. The vertical width of the end portion is larger than that of the front end side, and the strength of the base end portion is increased. As a result, when the belt B runs at a high speed or transmits a high torque (at a low speed and a high load), the upper beam 16 Can be prevented from being broken.
[0031]
The left and right substantially central portions of the upper surface of the upper beam portion 16, that is, positions sandwiched between the left and right bulging portions 21 and 21 have a small contribution to the increase in the strength of the base end portion of the upper beam portion 16. Since the concave portion 20 is formed in this portion, the vertical width of the upper beam portion 16, and hence the mass, is reduced by the amount of the concave portion 20. 7, the increase in the input load to the pulley P can be reduced.
[0032]
Further, an arc-shaped surface 23 in which the lower surface of the upper end of the upper beam portion 16, the upper surface of the base end of the lower beam portion 17, and the left and right side surfaces of the pillar portion 18 smoothly continue in a substantially arc shape. Is formed, the arc radius Ru of the boundary portion 24 between the lower surface of the upper end of the upper beam portion 16 and the left and right side surfaces of the pillar portion 18 and the upper surface of the lower end of the lower beam portion 17 and the pillar portion 18 Enlarging the arc radius Rd of the boundary portion 25 between the left and right side surfaces as much as possible to avoid concentration of stress on the base end portion of the upper beam portion 16 and the base end portion of the lower beam portion 17 of the reinforcing member 15. It can suppress that each base end part of the upper and lower beam parts 16 and 17 breaks.
[0033]
Furthermore, since the lower beam portion 17 of the reinforcing member 15 is curved so as to bulge an intermediate portion toward the distal end side upward, the rigidity of the lower beam portion 17 can be increased, and The lower end of the lower portion 17 is recessed upward to reduce the vertical width of the lower beam portion 17, that is, the mass, and to suppress the increase in the inertial force of the block 7 during high-speed traveling around the pulley P of the belt B, thereby reducing the pulley P. The increase in the input load to the can be reduced. Further, the curvature of the lower beam portion 17 increases the arc radius of the upper surface of the lower end of the lower beam portion 17 as much as possible to avoid concentration of stress on the lower end portion of the lower beam portion 17. Breakage of the base end can be suppressed.
[0034]
In the above embodiment, (a) the concave portion 20 and the bulging portions 21 and 21 are formed on the upper surface of the upper beam portion 16 of the reinforcing member 15, and (a) the distal end side of the lower beam portion 17 is curved. (C) the lower surface of the upper end portion of the upper beam portion 16, the upper surface of the lower end portion of the lower beam portion 17, and the left and right side surfaces of the pillar portion 18 form an arcuate surface 23 that smoothly smoothly continues in a substantially arc shape. However, the present invention should satisfy at least one of the above (A) to (C), and the same operational effects as described above can be obtained.
[0035]
In the above-described embodiment, the upper concave portion 2 as a meshed portion is formed on the upper surface of the tension band 1, and the upper concave portion 2 of the fitting band 8 of each block 7 is formed as a meshing portion that meshes with the upper concave portion 2 of the tension band 1. Each of the upper convex portions 9 is formed. In addition, for example, an upper convex portion as an engaged portion is formed on the upper surface of the tension band 1, and an upper convex portion of the upper surface of the tension band 1 is formed on the upper surface of the fitting groove 8 of each block 7. An upper concave portion may be provided as a meshing portion meshing with the portion. Further, a lower convex portion as a meshed portion is formed on the lower surface of the tension band 1 and a lower concave portion is formed as a meshing portion meshed with the lower convex portion of the lower surface of the tension band 1 on the lower surface of the fitting groove 8 of each block 7. Can also be provided.
[0036]
【The invention's effect】
As described above, according to the first aspect of the present invention, in a high load transmission V-belt including a tension band and a number of blocks engaged and fixed to the tension band in a meshing state, the resin portion of the block includes A recess is formed at approximately the center of the upper surface of the upper beam portion of the buried reinforcing member on the left and right sides, and the bulge bulges upward at a position adjacent to the concave portion on the upper surface of the upper beam portion on the left and right sides of the recess. The upper part is formed so as to correspond to the vicinity of the base end of the upper beam part, so that the increase in the inertial force of the block during high-speed traveling around the belt pulley is suppressed, and the increase in the input load to the pulley is reduced. The strength of the base end of the beam section is increased to prevent the base end of the upper beam section from breaking during high-speed running or high-torque transmission of the belt (at low speed and high load). Improve belt durability Can.
[0037]
According to the invention of claim 2, 3 or 4, the lower surface of the upper end portion of the upper beam portion, the upper surface of the lower end portion of the lower beam portion, and the left and right side surfaces of the pillar portion smoothly continue in a substantially arc shape. By forming the arc-shaped surface, the radius of the arc at the boundary between the lower surface of the upper end of the upper beam portion and the upper surface of the lower end of the lower beam portion and the left and right side surfaces of the pillar portion is made as large as possible. Also, it is possible to avoid concentration of stress on the base end of the upper and lower beam portions, to suppress breakage of each base end of the upper and lower beam portions, and to improve the durability of the high load transmission V-belt.
[0038]
According to the fifth aspect of the invention, the lower beam portion of the reinforcing member of the block has a structure in which the lower beam portion is curved so as to be directed upward and then downwardly toward the distal end thereof, whereby the rigidity of the lower beam portion is reduced. In addition to reducing the mass of the lower beam part, the increase in the inertial force of the block during high-speed running around the belt pulley can be suppressed, and the increase in the input load to the pulley can be reduced. Increase the radius of the arc on the upper surface of the base of the beam as much as possible to avoid concentration of stress on the base of the lower beam, suppress breakage of the base of the lower beam, and transmit high load. The durability of the V-belt for use can be improved.
[Brief description of the drawings]
FIG. 1 is an enlarged front view of a reinforcing member.
FIG. 2 is an enlarged front view of a block.
FIG. 3 is an enlarged cross-sectional view of the belt cut at a center in a thickness direction of the block.
FIG. 4 is a perspective view of a high-load transmission V-belt according to the embodiment of the present invention.
[Explanation of symbols]
B V belt for high load transmission 1 Tension band 2 Upper concave part (Upper meshed part)
3 Lower recess (lower engaged part)
7 Block 8 Fitting groove 9 Upper convex part (Upper mesh part)
10 Lower convex part (lower mesh part)
DESCRIPTION OF SYMBOLS 11 Contact part 14 Resin part 15 Reinforcement member 16 Upper beam part 17 Lower beam part 18 Pillar part 20 Depressed part 21 Swelling part 23 Arc-shaped surface 24 Boundary part 25 between lower surface of base part of upper beam part and left and right side surfaces of pillar part Boundary portion Ru between upper surface of lower beam base end portion and left and right side surfaces of pillar portion Radius Rd of boundary portion between lower surface of upper beam portion base bottom portion and left and right side surfaces of pillar portion Rd Left and right of upper surface of lower beam base end portion and pillar portion Radius D at the boundary with the side surface Diameter in the vertical direction of the arc-shaped surface P Transmission pulley P1 Pulley groove surface

Claims

A pair of left and right tension bands in which a number of upper meshed portions and lower meshed portions arranged in the belt length direction on the upper and lower surfaces are provided corresponding to the upper and lower sides,
On the left and right side surfaces in the belt width direction, the upper wall has an upper meshing portion that meshes with the upper meshed portion of each tension band, while the lower wall has a lower meshing portion that meshes with the lower meshed portion of the tension band. A plurality of blocks provided with a fitting groove, and provided with upper and lower contact portions that respectively contact the pulley groove surfaces on both upper and lower side surfaces of the fitting groove,
By fitting the tension band into the fitting groove of each block, each block is engaged and fixed to the tension band,
Each of the blocks includes a reinforcing member embedded in the resin portion so that at least the upper and lower meshing portions and the contact portion are formed of the resin portion,
The reinforcing member has a high-load transmission V including a vertical beam portion having a distal end positioned above and below the fitting groove, and a pillar portion connecting left and right central base ends of the vertical beam portion. A belt,
A concave portion is formed substantially at the center on the left and right of the upper surface of the upper beam portion of the reinforcing member so as to correspond to substantially directly above the pillar portion,
On the upper surface of the upper beam portion on the left and right sides of the concave portion, a swelling portion bulging upward is formed so as to be adjacent to the concave portion and correspond to near the base end of the upper beam portion. V belt for high load transmission.

A pair of left and right tension bands in which a number of upper meshed portions and lower meshed portions arranged in the belt length direction on the upper and lower surfaces are provided corresponding to the upper and lower sides,
On the left and right side surfaces in the belt width direction, the upper wall has an upper meshing portion that meshes with the upper meshed portion of each tension band, while the lower wall has a lower meshing portion that meshes with the lower meshed portion of the tension band. A plurality of blocks provided with a fitting groove, and provided with upper and lower contact portions that respectively contact the pulley groove surfaces on both upper and lower side surfaces of the fitting groove,
By fitting the tension band into the fitting groove of each block, each block is engaged and fixed to the tension band,
Each of the blocks includes a reinforcing member embedded in the resin portion so that at least the upper and lower meshing portions and the contact portion are formed of the resin portion,
The reinforcing member has a high-load transmission V including a vertical beam portion having a distal end positioned above and below the fitting groove, and a pillar portion connecting left and right central base ends of the vertical beam portion. A belt,
The lower surface of the upper end portion of the upper beam portion, the upper surface of the lower end portion of the lower beam portion, and the right and left side surfaces of the pillar portion form an arc-shaped surface that is smoothly continuous in a substantially arc shape. V belt for high load transmission.

The high load transmission V-belt according to claim 1,
A high-load transmission V-belt, wherein the lower surface of the upper end portion of the upper beam portion, the upper surface of the lower end portion of the lower beam portion, and the left and right side surfaces of the pillar portion are smoothly continuous in a substantially arc shape.

The high load transmission V-belt according to claim 2 or 3,
The boundary between the lower surface of the base end of the upper beam portion and the left and right side surfaces of the pillar portion in the arc-shaped surface,
And a radius of a boundary portion between the upper surface of the lower end of the lower beam portion and the left and right side surfaces of the pillar portion is 0.3 to 0.5 of an inner diameter in a vertical direction of the arc-shaped surface. belt.

A pair of left and right tension bands in which a number of upper meshed portions and lower meshed portions arranged in the belt length direction on the upper and lower surfaces are provided corresponding to the upper and lower sides,
On the left and right side surfaces in the belt width direction, the upper wall surface has an upper meshing portion that meshes with the upper meshing portion of each of the tension bands, while the lower wall surface has a lower meshing portion that meshes with the lower meshing portion of the tension band. A plurality of blocks provided with a fitting groove, and provided with upper and lower contact portions that respectively contact the pulley groove surfaces on both upper and lower side surfaces of the fitting groove,
By fitting the tension band into the fitting groove of each block, each block is engaged and fixed to the tension band,
Each of the blocks includes a reinforcing member embedded in the resin portion so that at least the upper and lower meshing portions and the contact portion are formed of the resin portion,
The reinforcing member has a high-load transmission V including a vertical beam portion having a distal end positioned above and below the fitting groove, and a pillar portion connecting left and right central base ends of the vertical beam portion. A belt,
The high load transmission V-belt, wherein the lower beam portion of the reinforcing member is curved so as to go upward as it goes toward its distal end and then go down.