JP2004239314A

JP2004239314A - V-ribbed belt, V-ribbed pulley, and belt transmission using them

Info

Publication number: JP2004239314A
Application number: JP2003027224A
Authority: JP
Inventors: Takehiro Hayashi; 丈浩林; Takahiro Tsutsumi; 孝裕堤; Hiroaki Imahari; 宏彰今治
Original assignee: Honda Motor Co Ltd; Bando Chemical Industries Ltd
Current assignee: Honda Motor Co Ltd; Bando Chemical Industries Ltd
Priority date: 2003-02-04
Filing date: 2003-02-04
Publication date: 2004-08-26
Anticipated expiration: 2023-02-04
Also published as: JP4250430B2

Abstract

【課題】心線が埋設されたベルト本体の下面にベルト長さ方向に延びかつベルト幅方向に並ぶ複数のリブ部を一体的に形成してなるＶリブドベルトと、外周面に複数のリブ溝が形成され、このリブ溝にそれぞれ上記Ｖリブドベルトのリブ部が係合することで、そのベルトが巻き掛けられるＶリブドプーリとを備えるベルト伝動装置において、Ｖリブドベルト及びＶリブドプーリ間のミスアラインメント発生時に、Ｖリブドベルトの反り変形によるベルト伝動装置の異音の発生を防止する。
【解決手段】ＶリブドベルトＢのリブ部１４，１４，…のうち、ベルト幅方向両端に位置する各端リブ部１４ａと、この各端リブ部１４ａに隣接する中間リブ部１４との間のリブピッチＰｒ´を基準リブピッチＰｒよりも小さくする。
【選択図】図１A V-ribbed belt integrally formed with a plurality of rib portions extending in a belt length direction and arranged in a belt width direction on a lower surface of a belt body in which a core wire is embedded, and a plurality of rib grooves on an outer peripheral surface. When the rib portion of the V-ribbed belt is engaged with each of the rib grooves, a V-ribbed pulley on which the belt is wound is provided. It is possible to prevent the belt transmission from generating abnormal noise due to the warped deformation of the ribbed belt.
The rib pitch between each end rib portion (14a) located at both ends in the belt width direction of the rib portions (14, 14, ...) of a V-ribbed belt (B) and an intermediate rib portion (14) adjacent to each end rib portion (14a). Pr ′ is made smaller than the reference rib pitch Pr.
[Selection diagram] Fig. 1

Description

【０００１】
【発明の属する技術分野】
本発明は、Ｖリブドベルト、Ｖリブドプーリ及びそれらを用いたベルト伝動装置に関する技術分野に属する。
【０００２】
【従来の技術】
従来より、心線が埋設されたベルト本体の下面にベルト長さ方向に延びかつベルト幅方向に並ぶ複数のリブ部を一体的に形成してなるＶリブドベルトと、外周面に複数のリブ溝が形成され、このリブ溝にそれぞれ上記Ｖリブドベルトのリブ部が係合することで、そのベルトが巻き掛けられるＶリブドプーリとを備えるベルト伝動装置は知られている。このＶリブドベルトは高伝動能力を有しかつ長寿命であることから、例えばエンジンの補機駆動用ベルトとしてＶベルトに代わり広く用いられている。
【０００３】
図８に示すように、このようなＶリブドベルトａは、通常、ベルト本体ｂと、このベルト本体ｂの上面（背面）側に一体的に接着された背面帆布層ｃとを備え、上記ベルト本体ｂのベルト厚さ方向中心には、略ベルト長さ方向に延びかつベルト幅方向に所定ピッチをあけて並ぶように螺旋状に巻かれた心線ｄ，ｄ，…が埋設されている。また、ベルト本体ｂの下面（底面）側にはリブゴム層ｅが形成され、このリブゴム層ｅの下面側にはそれぞれベルト長さ方向に延びる複数のリブ部ｆ，ｆ，…がベルト幅方向に所定の基準リブピッチで並んだ状態で一体的に設けられている。
【０００４】
ところで、このようなＶリブドベルト及びこのＶリブドベルトが巻き掛けられるＶリブドプーリを備えるベルト伝動装置においては、製作誤差等の理由によりＶリブドプーリとＶリブドベルトとの間で、Ｖリブドプーリの軸方向（ベルト幅方向）にミスアラインメントが生じたとき、ベルトに滑りが生じて異音が発生するという問題がある。
【０００５】
そこで、従来、Ｖリブドベルトの全てのリブ部のリブピッチをＶリブドプーリのリブ溝ピッチに対して小さく設定して、リブ部のリブ面とリブ溝面との面圧を増加させ、スリップを防止することが提案されている（例えば、特許文献１参照）。
【０００６】
しかし、全てのリブピッチをリブ溝ピッチよりも小さくすると、リブ部の数が増えたときに、ベルト幅方向でピッチの誤差が蓄積し、複数のリブ部のうち一部のリブ部にのみ偏摩耗が起こり、かえって異音が発生するおそれがある。
【０００７】
また、従来、Ｖリブドベルトの全てのリブ部における幅方向側面たるリブ面の、リブ幅中央を通る平面とのなす傾斜角度（以下、リブ角度という）をリブ溝の側面のリブ溝幅中央を通る平面とのなす傾斜角度（以下、リブ溝角度という）よりも大きくすることも知られている（例えば、特許文献２又は３参照）。
【０００８】
【特許文献１】
特開２００２−３９２９１号公報
【特許文献２】
実開昭６３−１４７９５１号公報
【特許文献３】
特開２０００−７４１５３号公報
【０００９】
【発明が解決しようとする課題】
ところで、上記リブ角度をリブ溝角度よりも大きくするものでも、図８に示すように、Ｖリブドベルトａの上記リブ部ｆ，ｆ，…のうち、ベルト幅方向両端に位置する端リブ部ｇ，ｇの片側はフリーで他のリブ部ｆとの連続による干渉がないため、他のリブ部ｆ，ｆ，…よりも変形を起こしやすい。例えば、ＶリブドベルトａがＶリブドプーリｈに巻き付いたときに、端リブ部ｇ，ｇがベルト背面側に向かって変形する反りが発生し、この反りの発生に伴い、ベルト張力がベルト幅方向で増大するので、このベルト張力により、端リブ部ｇ，ｇを押し戻そうとするラジアル方向の力が働いて端リブ部ｇ，ｇが溝ｉ内にスリップして入る。このことで、Ｖリブドプーリｈの半径方向に滑りと密着とを交互に繰り返すスティックスリップ現象が生じ、この滑りにより、ベルト伝動装置に異音が発生するという問題がある。
【００１０】
本発明は斯かる点に鑑みてなされたものであり、その目的とするところは、Ｖリブドベルトの端リブ部又はこの端リブ部が係合するＶリブドプーリの端リブ溝の形状を工夫することにより、Ｖリブドベルトの反り変形による異音の発生を防止することにある。
【００１１】
【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、心線が埋設されたベルト本体の下面に、ベルト長さ方向に延びかつベルト幅方向に並ぶ複数のリブ部を一体的に形成してなるＶリブドベルトにおいて、リブ部がＶリブドプーリのリブ溝に係合したときに、ベルト幅方向両端に位置する端リブ部におけるベルト幅方向端側の外側リブ面と、この外側リブ面が当接するＶリブドプーリのリブ溝面との面圧が、他のリブ面とリブ溝面との面圧よりも低く設定されるようにする。
【００１２】
上記の構成によると、端リブ部の外側リブ面とリブ溝面との面圧が他のリブ面とリブ溝面との面圧よりも低く設定されているため、Ｖリブドベルトの端リブ部の変形を防止し、この端リブ部を押し戻そうとするラジアル方向の力を抑えることができる。従って、Ｖリブドプーリの半径方向に滑りと密着とを交互に繰り返すというスティックスリップ現象が防がれ、ＶリブドプーリとＶリブドベルトとの間でミスアラインメントが生じていても異音の発生が抑えられる。
【００１３】
請求項２の発明では、端リブ部と、この端リブ部に隣接する中間リブ部との間のリブピッチが基準リブピッチよりも小さくなるようにする。また、請求項３の発明では、端リブ部と、この端リブ部に隣接する中間リブ部との間のリブピッチが基準リブピッチと同じであり、端リブ部においてこの端リブ部に隣接する中間リブ部のリブ幅中央位置から基準リブピッチだけ離れた位置を通る平面に対する外側リブ面の距離が、この平面に対するベルト幅方向中央側の内側リブ面の距離よりも小さくなるようにする。さらに、請求項４の発明では、端リブ部の外側リブ面とこの端リブ部のリブ幅中央を通る平面とのなす傾斜角度が他のリブ面よりも小さくなるようにする。
【００１４】
上記の構成によると、いずれの発明においても、Ｖリブドベルトの両端の端リブ部の外側リブ面と、これに当接するＶリブドプーリのリブ溝面との間隔のみを他のリブ面とリブ溝面との間隔よりも大きくなるようにしているため、端リブ部以外の他のリブ面とリブ溝面との位置関係は変わらず、両者の当接に悪影響を及ぼすことなく端リブ部の外側リブ面とリブ溝面との面圧を、他のリブ部のリブ面とリブ溝面との面圧よりも低くすることができる。従って、本発明の作用効果が顕著に発揮されるＶリブドベルトが得られる。
【００１５】
請求項５の発明では、外周面に、内周方向に延びかつプーリ幅方向に並ぶ複数のリブ溝を形成してなるＶリブドプーリにおいて、リブ溝にＶリブドベルトのリブ部が係合したときに、プーリ幅方向両端に位置する端リブ溝におけるプーリ幅方向端側の外側溝面と、この外側溝面が当接するＶリブドベルトのリブ部のリブ面との面圧が、他のリブ溝面とリブ面との面圧よりも低く設定されるようにする。
【００１６】
上記の構成によると、Ｖリブドプーリの端リブ溝の外側溝面と、Ｖリブドベルトのリブ部のリブ面との面圧が他のリブ溝面とリブ面との面圧よりも低くされているため、請求項１の発明と同様の作用効果が得られるＶリブドプーリが得られる。
【００１７】
請求項６の発明では、端リブ溝と、この端リブ溝に隣接する中間リブ溝との間のリブ溝ピッチが基準リブ溝ピッチよりも大きくなるようにする。また、請求項７の発明では、端リブ溝と、この端リブ溝に隣接する中間リブ溝との間のリブ溝ピッチが基準リブ溝ピッチと同じであり、端リブ溝において該端リブ溝に隣接する中間リブ溝のリブ溝幅中央位置から上記基準リブ溝ピッチだけ離れた位置を通る平面に対するリブ溝の外側溝面の距離が、ベルト幅方向中央側のリブ溝の内側溝面よりも大きくなるようにする。さらに、請求項８の発明では、端リブ溝の外側溝面のリブ溝幅中央を通る平面とのなす傾斜角度が他のリブ溝のリブ溝面よりも大きくなるようにする。
【００１８】
上記の構成によると、いずれの発明においても、Ｖリブドプーリの両端における端リブ溝の外側溝面と、これに当接するリブ部の外側リブ面との間隔のみを他の内側溝面とリブ面との間隔よりも大きくしているため、他の内側溝面とリブ面との当接に悪影響を及ぼすことなく、端リブ溝の外側溝面と、端リブ部のリブ面との面圧を、他のリブ溝面とリブ面との面圧よりも低くすることができる。従って、本発明の作用効果が顕著に発揮されるＶリブドプーリが得られる。
【００１９】
請求項９の発明では、心線が埋設されたベルト本体の下面にベルト長さ方向に延びかつベルト幅方向に並ぶ複数のリブ部を一体的に形成してなるＶリブドベルトと、このＶリブドベルトが巻き掛けられるＶリブドプーリとを備えるベルト伝動装置において、Ｖリブドベルトのリブ部がプーリのリブ溝に係合したとき、ベルト幅方向両端に位置する端リブ部におけるベルト幅方向端側の外側リブ面と、プーリ幅方向両端に位置する端リブ溝において、外側リブ面が当接する外側溝面との面圧が、他のリブ面とリブ溝面との面圧よりも低く設定されるようにする。
【００２０】
上記の構成によると、Ｖリブドベルトの端リブ部又はＶリブドプーリの端リブ溝の少なくとも一方の形状を工夫することで、Ｖリブドベルトの外側リブ面と、この外側リブ面が当接するＶリブドプーリの端リブ溝の外側溝面との面圧が、他のリブ部のリブ面とリブ溝面との面圧よりも低くなる。従って、本発明の作用効果が顕著に発揮されるベルト伝動装置が得られる。
【００２１】
【発明の実施の形態】
（実施形態１）
以下、本発明の実施形態を図面に基づいて詳細に説明する。図２は本発明の実施形態１に係るベルト伝動装置１を示し、このベルト伝動装置１は、詳細は図示しないが、例えば自動車に搭載されるエンジンによりその補機を駆動するもので、図外のエンジンのクランク軸に取り付けられた駆動プーリ２と、オートテンショナ９に設けられるテンションプーリ３と、図示しない補機の回転軸に取り付けられた第１及び第２補機プーリ４，５とを有する。上記駆動プーリ２と、第１及び第２補機プーリ４，５とはいずれもＶリブドプーリからなる一方、テンションプーリ３は平プーリからなる。これらのプーリ２〜５間にＶリブドベルトＢが巻き掛けられており、自動車エンジンの運転に伴う駆動プーリ２の回転によりＶリブドベルトＢを駆動プーリ２→テンションプーリ３→第１補機プーリ４→第２補機プーリ５→駆動プーリ２の順に図２で時計回り方向に走行させて、各補機を駆動するようにしている。
【００２２】
上記ＶリブドベルトＢは、図１に示すように、ベルト本体１０と、このベルト本体１０の上面（背面）側に一体的に形成された背面帆布層１１とを備え、上記ベルト本体１０のベルト厚さ方向中心には、略ベルト長さ方向に延びかつベルト幅方向に所定ピッチをあけて並ぶように螺旋状に巻かれた心線１２，１２，…が埋設されている。また、ベルト本体１０の下面（底面）側にはリブゴム層１３が形成され、このリブゴム層１３の下面側にはそれぞれベルト長さ方向に延びる複数のリブ部１４，１４，…がベルト幅方向に並んだ状態で一体的に設けられている。この各リブ部１４を含むリブゴム層１３には、補強等の目的で短繊維（図示せず）がベルト幅方向に配向された状態で含有されている。
【００２３】
そして、上記リブゴム層１３の各リブ部１４がベルト伝動装置１の上記各Ｖリブドプーリ（駆動プーリ２、第１及び第２補機プーリ４，５）に当接して動力伝達の主体となる一方、ベルト背面がフラットなテンションプーリ３に当接するように巻き掛けられて動力伝達の一端を担っている。
【００２４】
以下、上記Ｖリブドプーリの中で、特にＶリブドベルトＢとのミスアラインメントが現れやすい第１補機プーリ４について記載する。
【００２５】
本発明の特徴として、上記ＶリブドベルトＢにおいて、ベルト幅方向両端に位置する各端リブ部１４ａ及びこの端リブ部１４ａに隣接する中間リブ部としてのリブ部１４間のリブピッチＰｒ´のみが他のリブ部１４，１４同士間のリブピッチである基準リブピッチＰｒよりも小さくされている（Ｐｒ´＜Ｐｒ）。
【００２６】
一方、上記第１補機プーリ４は、上記リブ部１４，１４，…の基準リブピッチＰｒに対応するように、全てこの基準リブピッチＰｒと同じ間隔のリブ溝ピッチＰｇでその外周面に、内周方向に延びかつプーリ幅方向に並ぶ複数のリブ溝２０，２０，…を有している。
【００２７】
そして、上記ＶリブドベルトＢが第１補機プーリ４に巻き掛けられ、各リブ部１４が第１補機プーリ４のリブ溝２０に係合したときには、各端リブ部１４ａにおけるベルト幅方向端側の外側リブ面１４ｂと、この外側リブ面１４ｂが当接する第１補機プーリ４のリブ溝２０の外側溝面２０ａとの面圧が、他の内側リブ面１４ｃとリブ溝２０の内側溝面２０ｂとの面圧よりも低くなるように構成されている。
【００２８】
次に、本発明の実施形態１に係るＶリブドベルトＢ及びそれを備えるベルト伝動装置１の作動を説明する。自動車エンジンの運転により駆動プーリ２が回転し、その駆動力がＶリブドベルトＢを介して第１補機プーリ４に伝達されて補機が駆動される。
【００２９】
このとき、通常、図２に示すように、テンションプーリ３と第１補機プーリ４との間には、製造誤差等の要因により、第１補機プーリ４の幅方向中央とベルト駆動ラインｘとがずれるというミスアラインメントｙが生じる。このミスアラインメントｙが大きくなると、ＶリブドベルトＢと第１補機プーリ４との間で異音が発生しようとする。
【００３０】
つまり、従来、Ｖリブドベルトの各端リブ部の片側はフリーで他のリブ部との連続による干渉がないため、他のリブ部よりも変形を起こしやすい。このことで、端リブ部がベルト背面側に向かって変形する反りが発生し、この反りの発生に伴い、ベルト張力がベルト幅方向で増大するので、このベルト張力により、端リブ部を押し戻そうとするラジアル方向の力が働いて端リブ部内にスリップして入る。また、特に各リブ部に短繊維が含まれている場合には、各端リブ部の外側リブ面から突出している短繊維がこのスリップにより摩耗してしまい、外側リブ面の摩擦係数が増加して引っかかりやすくなる。このことで、Ｖリブドプーリの半径方向に滑りと密着とを交互に繰り返すスティックスリップ現象が生じ、この滑りにより、ベルト伝動装置に異音を発生させようとする。
【００３１】
しかし、本発明の実施形態１に係るＶリブドベルトＢによると、各端リブ部１４ａと、この端リブ部１４ａに隣接する中間のリブ部１４との間のリブピッチＰｒ´が基準リブピッチＰｒよりも小さいため、端リブ部１４ａの外側リブ面１４ｂと、これに当接するリブ溝２０の外側溝面２０ａとの間隔のみが他の各リブ部１４の内側リブ面１４ｃとリブ溝２０の内側溝面２０ｂとの間隔よりも大きくなる。
【００３２】
このため、各端リブ部１４ａの外側リブ面１４ｂにおけるリブ溝２０の外側溝面２０ａに対する局所的な当たりが防がれるとともに、各端リブ部１４ａの外側リブ面１４ｂとリブ溝２０の外側溝面２０ａとの面圧が他の内側リブ面１４ｃとリブ溝２０の内側溝面２０ｂとの面圧よりも低くなる。
【００３３】
このことで、ＶリブドベルトＢの各端リブ部１４ａの変形を防止し、端リブ部１４ａを押し戻そうとするラジアル方向の力を抑えることができる。従って、第１補機プーリ４の半径方向に滑りと密着とを交互に繰り返すスティックスリップ現象が防がれる。
【００３４】
また、端リブ部１４ｂ以外の他の各リブ部１４の内側リブ面１４ｃと各リブ溝２０の内側溝面２０ｂとの位置関係は変わらないため、全リブピッチを基準リブピッチＰｒよりも小さくする場合のように、ピッチ誤差がベルト幅方向に重なった部分の第１補機プーリとＶリブドベルトとの間の面圧に偏りが生じて偏摩耗が発生するようなことはない。
【００３５】
従って、第１補機プーリ４とＶリブドベルトＢとの間でミスアラインメントｙが生じていても異音の発生が抑えられる。
【００３６】
（実施形態２）
図３は本発明の実施形態２を示し（尚、以下の各実施形態では、図１と同じ部分については同じ符号を付してその詳細な説明は省略する）、ＶリブドベルトＢの端リブ部１４ａ，１４ａの形状が異なる点で上記実施形態１と異なる。
【００３７】
具体的には、各端リブ部１４ａと、この端リブ部１４ａに隣接する中間リブ部としてのリブ部１４との間のリブピッチＰｒ´が基準リブピッチＰｒと等しくなっている（Ｐｒ´＝Ｐｒ）。一方、上記各端リブ部１４ａにおいて、この端リブ部１４ａに隣接するリブ部１４のリブ幅中央位置から上記基準リブピッチＰｒだけ離れた位置を通る平面Ａに対する外側リブ面１４ｂの距離が、ベルト幅方向中央側の内側リブ面１４ｃの平面Ａからの距離よりも小さくなっている。
【００３８】
つまり、外側リブ面１４ｂの端リブ部１４ａの平面Ａとの傾斜角度θｒ´は他の各中間リブ部１４の内側リブ面１４ｃの傾斜角度（以下、基準リブ角度という）θｒと同じであるが（θｒ´＝θｒ）、例えばベルト背面側のリブ面の頂点に着目すると、上記平面Ａから外側リブ面１４ｂのリブ面頂点までのベルト幅方向の距離ｚが、平面Ａから内側リブ面１４ｃのベルト背面側のリブ面頂点までのベルト幅方向の距離Ｐｒ／２よりも小さくなっている（ｚ＜Ｐｒ／２）。
【００３９】
従って、本実施形態２においても、上記実施形態１と同様に、ＶリブドベルトＢの端リブ部１４ａの外側リブ面１４ｂと、これに当接するリブ溝２０の外側溝面２０ａとの間隔のみが他の内側リブ面１４ｃとリブ溝２０の内側溝面２０ｂとの間隔よりも大きくなり、他の内側リブ面１４ｃとリブ溝２０の内側溝面２０ｂとの当接に悪影響を及ぼすことなく、本発明の作用効果が得られるＶリブドベルトＢが得られる。
【００４０】
（実施形態３）
図４は本発明の実施形態３を示し、ＶリブドベルトＢの端リブ部１４ａ，１４ａの形状が異なる点で上記実施形態１と異なる。
【００４１】
すなわち、各端リブ部１４ａのリブピッチＰｒ´は基準リブピッチＰｒと等しいが（Ｐｒ´＝Ｐｒ）、外側リブ面１４ｂの端リブ部１４ａのリブ幅中央を通る平面との傾斜角度（以下、端リブ角度という）θｒ´が他のリブ部１４の基準リブ角度θｒよりも小さくなっている（θｒ´＜θｒ）。
【００４２】
従って、本実施形態３においても、上記実施形態１と同様に、ＶリブドベルトＢの端リブ部１４ａの外側リブ面１４ｂと、これに当接するリブ溝２０の外側溝面２０ａとの間隔のみが他の内側リブ面１４ｃとリブ溝２０の内側溝面２０ｂとの間隔よりも大きくなり、他の内側リブ面１４ｃとリブ溝２０の内側溝面２０ｂとの当接に悪影響を及ぼすことなく、本発明の作用効果が発揮されるＶリブドベルトＢが得られる。
【００４３】
（実施形態４）
図５は本発明の実施形態４を示し、ＶリブドベルトＢの端リブ部１４ａ，１４ａ及び第１補機プーリ４の両端の端リブ溝２０ｃ，２０ｃの形状が異なる点で上記実施形態１と異なる。
【００４４】
すなわち、ＶリブドベルトＢの各リブ部１４，１４間のリブピッチが全て基準リブピッチＰｒと等しい一方、第１補機プーリ４の各端リブ溝２０ｃと、この各端リブ溝２０ｃに隣接する中間リブ溝としてのリブ溝２０との間のリブ溝ピッチＰｇ´が他のリブ溝２０，２０間の基準リブ溝ピッチＰｇよりも大きくなっている（Ｐｇ´＞Ｐｇ）。
【００４５】
従って、本実施形態４においては、第１補機プーリ４側のリブ溝ピッチＰｇ´のみを基準リブ溝ピッチＰｇよりも大きくすることで、リブ溝２０，２０，…にＶリブドベルトＢのリブ部１４，１４，…が係合したときに、第１補機プーリ４の端リブ溝２０ｃの外側溝面２０ａと、これに当接するＶリブドベルトＢの端リブ部１４ａの外側リブ面１４ｂとの間隔のみが他の内側リブ面１４ｃとリブ溝２０の内側溝面２０ｂとの間隔よりも大きくなっている。このことで、外側溝面２０ａと外側リブ面１４ｂとの面圧が他の内側溝面２０ｂと内側リブ面１４ｃとの面圧よりも低くなっているため、実施形態１の発明と同様の作用効果が得られる第１補機プーリ４が得られる。
【００４６】
（実施形態５）
図６は本発明の実施形態５を示し、ＶリブドベルトＢの端リブ部１４ａ，１４ａ及び第１補機プーリ４の両端の端リブ溝２０ｃ，２０ｃの形状が異なる点で上記実施形態１と異なる。
【００４７】
すなわち、第１補機プーリ４の各端リブ溝２０ｃと、この端リブ溝２０ｃに隣接する中間のリブ溝２０との間のリブ溝ピッチＰｇ´が基準リブ溝ピッチＰｇと同じとなっている（Ｐｇ´＝Ｐｇ）。そして、各端リブ溝２０ｃにおいて、この端リブ溝２０ｃに隣接するリブ溝２０のリブ溝幅中央位置から基準リブ溝ピッチＰｇだけ離れた位置を通る平面Ａ´に対する端リブ溝２０ｃの外側溝面２０ａの距離が、ベルト幅方向中央側のリブ溝２０の内側溝面２０ｂの平面Ａ´からの距離よりも大きくなっている。
【００４８】
つまり、端リブ溝２０ｃの外側溝面２０ａの平面Ａ´との傾斜角度（以下、端リブ溝角度という）θｇ´は他の各中間のリブ溝２０の内側溝面２０ｂの傾斜角度（以下、基準リブ溝角度という）θｇと同じであるが（θｇ´＝θｇ）、例えばベルト背面側の溝側面の頂点に着目すると、上記平面Ａ´から外側溝面２０ａの頂点までのベルト幅方向の距離ｗが、平面Ａ´からベルト幅方向中央側のリブ溝２０の内側溝面２０ｂの頂点までのベルト幅方向の距離Ｐｇ／２よりも大きくなっている（ｗ＞Ｐｇ／２）。
【００４９】
従って、本実施形態５においては、第１補機プーリ４の端リブ溝２０ｃの外側溝面２０ａのみを平面Ａ´から遠ざけることで、外側溝面２０ａと、リブ部１４の外側リブ面１４ｂとの面圧が他のリブ溝２０の内側溝面２０ｂと内側リブ面１４ｃとの面圧よりも低くなっているため、実施形態１の発明と同様の作用効果が得られる第１補機プーリ４が得られる。
【００５０】
（実施形態６）
図７は本発明の実施形態６を示し、ＶリブドベルトＢの端リブ部１４ａ，１４ａ及び第１補機プーリ４の両端の端リブ溝２０ｃ，２０ｃの形状が異なる点で上記実施形態１と異なる。
【００５１】
すなわち、端リブ溝２０ｃの外側溝面２０ａにおける端リブ溝２０ｃのリブ溝幅中央を通る平面との傾斜角度（以下、端リブ溝角度という）θｇ´が他のリブ溝２０の基準リブ溝角度θｇよりも大きくなっている（θｇ´＞θｇ）。
【００５２】
従って、本実施形態６おいては、端リブ溝２０ｃの端リブ溝角度θｇ´のみを基準リブ溝角度θｇよりも大きくすることで、端リブ溝２０ｃの外側溝面２０ａと、リブ部１４の外側リブ面１４ｂとの面圧が他のリブ溝２０の内側溝面２０ｂと内側リブ面１４ｃとの面圧よりも低くなっているため、実施形態１の発明と同様の作用効果が得られる第１補機プーリ４が得られる。
【００５３】
尚、上記各実施形態では、Ｖリブドプーリとして、第１補機プーリ４についてのみ述べたが、他のＶリブドプーリに本発明が適用できるのは勿論のことである。
【００５４】
また、上記各実施形態では、ＶリブドベルトＢ又は第１補機プーリ４のどちらか一方の形状について述べているが、上記実施形態１〜３のいずれか１つのＶリブドベルトＢ又は上記実施形態４〜６のいずれか１つの第１補機プーリ４の少なくとも１つを備えるベルト伝動装置であれば、本発明が適用できる。
【００５５】
【発明の効果】
以上説明したように、請求項１の発明のＶリブドベルトによると、リブ部がＶリブドプーリのリブ溝に係合したときに、端リブ部におけるベルト幅方向端側の外側リブ面と、この外側リブ面が当接するＶリブドプーリのリブ溝面との面圧を、他のリブ部のリブ面とリブ溝面との面圧よりも低く設定したことにより、Ｖリブドプーリとの間でミスアラインメントが生じていてもＶリブドベルトの反り変形を抑制して、異音の発生が抑えられる。
【００５６】
請求項２の発明では、端リブ部と、この端リブ部に隣接する中間リブ部との間のリブピッチを基準リブピッチよりも小さくした。また、請求項３の発明では、端リブ部と、この端リブ部に隣接する中間リブ部との間のリブピッチを基準リブピッチと同じとし、端リブ部において、この端リブ部に隣接する中間リブ部のリブ幅中央位置から基準リブピッチだけ離れた位置を通る平面に対する外側リブ面の距離を、この平面に対するベルト幅方向中央側の内側リブ面の距離よりも小さくした。さらに、請求項４の発明では、端リブ部の外側リブ面と端リブ部のリブ幅中央を通る平面とのなす傾斜角度を他のリブ面よりも小さくした。これらの発明によると、本発明の作用効果が顕著に発揮されるＶリブドベルトが得られる。
【００５７】
請求項５の発明のＶリブドプーリによると、リブ溝にＶリブドベルトのリブ部が係合したときに、プーリ幅方向両端に位置する端リブ溝におけるプーリ幅方向端側の外側溝面と、この外側溝面が当接するＶリブドベルトのリブ部のリブ面との面圧を、他のリブ溝面とリブ面との面圧よりも低く設定したことにより、Ｖリブドベルトとの間でミスアラインメントが生じていてもＶリブドベルトの反り変形が抑制され、異音の発生が抑えられる。
【００５８】
請求項６の発明では、端リブ溝と、この端リブ溝に隣接する中間リブ溝との間のリブ溝ピッチを基準リブ溝ピッチよりも大きくした。また、請求項７の発明では、端リブ溝と、この端リブ溝に隣接する中間リブ溝との間のリブ溝ピッチを基準リブ溝ピッチと同じとし、端リブ溝においてこの端リブ溝に隣接する中間リブ溝のリブ溝幅中央位置から上記リブ溝ピッチだけ離れた位置を通る平面に対するリブ溝の外側溝面の距離を、この平面に対するベルト幅方向中央側のリブ溝の内側溝面よりも大きくした。さらに、請求項８の発明では、端リブ溝の外側溝面と端リブ溝のリブ溝幅中央を通る平面とのなす傾斜角度を他のリブ溝面よりも大きくした。これらの発明によると、本発明の作用効果が顕著に発揮されるＶリブドプーリが得られる。
【００５９】
請求項９の発明のベルト伝動装置によると、Ｖリブドベルトのリブ部がプーリのリブ溝に係合したとき、ベルト幅方向両端に位置する端リブ部におけるベルト幅方向端側の外側リブ面と、プーリ幅方向両端に位置する端リブ溝において、外側リブ面が当接する外側溝面との面圧を、他のリブ面とリブ溝面との面圧よりも低く設定したことにより、本発明の作用効果が顕著に発揮されるベルト伝動装置が得られる。
【図面の簡単な説明】
【図１】実施形態１に係るＶリブドベルトとＶリブドプーリとの関係を表す断面図である。
【図２】本発明の実施形態１に係るＶリブドベルト及びＶリブドプーリを用いたベルト伝動装置の全体図である。
【図３】実施形態２を示す図１相当図である。
【図４】実施形態３を示す図１相当図である。
【図５】実施形態４を示す図１相当図である。
【図６】実施形態５を示す図１相当図である。
【図７】実施形態６を示す図１相当図である。
【図８】従来例に係るＶリブドベルトとＶリブドプーリとの関係を表す断面図である。
【符号の説明】
ＢＶリブドベルト
Ｐｒ基準リブピッチ
Ｐｒ´ リブピッチ
Ｐｇ基準リブ溝ピッチ
Ｐｇ´ リブ溝ピッチ
１ベルト伝動装置
４第１補機プーリ（Ｖリブドプーリ）
１０ベルト本体
１２心線
１４リブ部
１４ａ端リブ部
１４ｂ外側リブ面
１４ｃ内側リブ面
２０リブ溝
２０ａ外側溝面
２０ｂ内側溝面
２０ｃ端リブ溝[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention belongs to the technical field of a V-ribbed belt, a V-ribbed pulley, and a belt transmission using the same.
[0002]
[Prior art]
Conventionally, a V-ribbed belt integrally formed with a plurality of rib portions extending in a belt length direction and arranged in a belt width direction on a lower surface of a belt body in which a core wire is embedded, and a plurality of rib grooves on an outer peripheral surface are provided. There is known a belt transmission device including a V-ribbed pulley around which the belt is wound by engaging the rib portions of the V-ribbed belt with the rib grooves. This V-ribbed belt has a high transmission capacity and a long life, and is widely used instead of a V-belt, for example, as a belt for driving an auxiliary machine of an engine.
[0003]
As shown in FIG. 8, such a V-ribbed belt a generally includes a belt body b and a back canvas layer c integrally bonded to an upper surface (back surface) of the belt body b. At the center of the belt thickness direction b, core wires d, d,..., which extend substantially in the belt length direction and are spirally wound so as to be arranged at a predetermined pitch in the belt width direction, are embedded. A rib rubber layer e is formed on the lower surface (bottom surface) side of the belt body b, and a plurality of rib portions f, f,... Extending in the belt length direction are formed on the lower surface side of the rib rubber layer e in the belt width direction. They are integrally provided in a state of being arranged at a predetermined reference rib pitch.
[0004]
By the way, in a belt transmission device including such a V-ribbed belt and a V-ribbed pulley around which the V-ribbed belt is wound, an axial direction of the V-ribbed pulley (belt width direction) is formed between the V-ribbed pulley and the V-ribbed belt due to a manufacturing error or the like. When the misalignment occurs in (1), there is a problem that the belt slips and abnormal noise is generated.
[0005]
Therefore, conventionally, the rib pitch of all the rib portions of the V-ribbed belt is set to be smaller than the rib groove pitch of the V-ribbed pulley, so that the surface pressure between the rib surfaces of the rib portions and the rib groove surface is increased to prevent slip. Has been proposed (for example, see Patent Document 1).
[0006]
However, if all the rib pitches are smaller than the rib groove pitch, when the number of rib portions increases, pitch errors accumulate in the belt width direction, and uneven wear occurs only in some of the plurality of rib portions. This may cause abnormal noise.
[0007]
Conventionally, an inclination angle (hereinafter, referred to as a rib angle) between a rib surface as a width side surface of all the rib portions of the V-ribbed belt and a plane passing through the center of the rib width passes through the center of the rib groove width on the side surface of the rib groove. It is also known to make the angle larger than the inclination angle with the plane (hereinafter, referred to as a rib groove angle) (for example, see Patent Documents 2 and 3).
[0008]
[Patent Document 1]
JP-A-2002-39291
[Patent Document 2]
JP-A-63-147951
[Patent Document 3]
JP 2000-74153 A
[0009]
[Problems to be solved by the invention]
By the way, even if the rib angle is larger than the rib groove angle, as shown in FIG. 8, among the rib portions f, f,... Of the V-ribbed belt a, the end rib portions g, Since one side of g is free and does not interfere with the other ribs f due to continuity, it is easier to deform than the other ribs f, f,. For example, when the V-ribbed belt a is wound around the V-ribbed pulley h, a warp occurs in which the end ribs g, g are deformed toward the back side of the belt, and the belt tension increases in the belt width direction due to the warpage. Therefore, due to the belt tension, a radial force for pushing back the end ribs g, g acts to cause the end ribs g, g to slip into the groove i. This causes a stick-slip phenomenon in which the V-ribbed pulley h alternately slides and adheres in the radial direction, and this slip causes a problem that abnormal noise is generated in the belt transmission device.
[0010]
The present invention has been made in view of such a point, and an object thereof is to improve the shape of an end rib portion of a V-ribbed belt or an end rib groove of a V-ribbed pulley with which the end rib portion engages. And V-ribbed belts to prevent generation of abnormal noise due to warpage deformation.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, in the invention of claim 1, a plurality of rib portions extending in the belt length direction and arranged in the belt width direction are integrally formed on the lower surface of the belt main body in which the cords are embedded. In the V-ribbed belt, when the rib portion engages with the rib groove of the V-ribbed pulley, the outer rib surface on the belt width direction end side of the end rib portion located at both ends in the belt width direction comes into contact with the outer rib surface. The surface pressure on the rib groove surface of the V-ribbed pulley is set lower than the surface pressure on the other rib surface and the rib groove surface.
[0012]
According to the above configuration, the surface pressure between the outer rib surface and the rib groove surface of the end rib portion is set lower than the surface pressure between the other rib surface and the rib groove surface. Deformation can be prevented, and a radial force for pushing back the end rib can be suppressed. Therefore, the stick-slip phenomenon of alternately repeating sliding and contact in the radial direction of the V-ribbed pulley is prevented, and generation of abnormal noise is suppressed even if misalignment occurs between the V-ribbed pulley and the V-ribbed belt.
[0013]
According to the second aspect of the present invention, the rib pitch between the end rib and the intermediate rib adjacent to the end rib is made smaller than the reference rib pitch. According to the third aspect of the present invention, the rib pitch between the end rib and the intermediate rib adjacent to the end rib is the same as the reference rib pitch, and the intermediate rib adjacent to the end rib at the end rib is provided. The distance between the outer rib surface and a plane passing through a position separated from the center position of the rib width by the reference rib pitch is smaller than the distance between the inner rib surface on the center side in the belt width direction and the plane. Further, in the invention according to claim 4, the inclination angle between the outer rib surface of the end rib portion and a plane passing through the center of the rib width of the end rib portion is made smaller than the other rib surfaces.
[0014]
According to the above configuration, in any of the inventions, only the distance between the outer rib surface of the end rib portion at each end of the V-ribbed belt and the rib groove surface of the V-ribbed pulley abutting on the other rib surface and the rib groove surface. Is larger than the distance between the ribs, so that the positional relationship between the rib surface other than the end ribs and the rib groove surface does not change, and the outer rib surfaces of the end ribs do not adversely affect the contact between them. The surface pressure between the rib surface and the rib groove surface can be made lower than the surface pressure between the rib surface of the other rib portion and the rib groove surface. Therefore, a V-ribbed belt in which the effects of the present invention are remarkably exhibited can be obtained.
[0015]
In the V-ribbed pulley having a plurality of rib grooves extending in the inner circumferential direction and arranged in the pulley width direction on the outer peripheral surface, when the rib portion of the V-ribbed belt is engaged with the rib groove, The surface pressure between the outer groove surface on the pulley width direction end side of the end rib grooves located at both ends in the pulley width direction and the rib surface of the rib portion of the V-ribbed belt with which the outer groove surface abuts is different from that of the other rib groove surfaces. The surface pressure is set lower than the surface pressure.
[0016]
According to the above configuration, the surface pressure of the outer groove surface of the end rib groove of the V-ribbed pulley and the surface pressure of the rib surface of the rib portion of the V-ribbed belt are lower than the surface pressure of the other rib groove surface and the rib surface. Thus, a V-ribbed pulley having the same functions and effects as those of the first aspect can be obtained.
[0017]
In the invention according to claim 6, the rib groove pitch between the end rib groove and the intermediate rib groove adjacent to the end rib groove is set to be larger than the reference rib groove pitch. In the invention of claim 7, the pitch of the rib groove between the end rib groove and the intermediate rib groove adjacent to the end rib groove is the same as the reference rib groove pitch. The distance between the outer groove surface of the rib groove and the inner groove surface of the rib groove on the center side in the belt width direction with respect to a plane passing through a position separated by the reference rib groove pitch from the center position of the rib groove width of the adjacent intermediate rib groove is larger. To be. Further, in the invention of claim 8, the inclination angle between the outer groove surface of the end rib groove and the plane passing through the center of the rib groove width is made larger than the rib groove surfaces of the other rib grooves.
[0018]
According to the above configuration, in any of the inventions, only the gap between the outer groove surface of the end rib groove at each end of the V-ribbed pulley and the outer rib surface of the rib portion abutting on the other groove surface is different from the other inner groove surface and the rib surface. The gap between the outer rib surface of the end rib groove and the surface pressure of the rib surface of the end rib portion without adversely affecting the contact between the other inner groove surface and the rib surface. The surface pressure between the other rib groove surface and the rib surface can be made lower. Therefore, a V-ribbed pulley in which the effects of the present invention are remarkably exhibited can be obtained.
[0019]
According to the ninth aspect of the present invention, a V-ribbed belt is formed by integrally forming a plurality of rib portions extending in a belt length direction and arranged in a belt width direction on a lower surface of a belt main body in which a core wire is embedded, In a belt transmission having a V-ribbed pulley to be wound around, when a rib portion of the V-ribbed belt is engaged with a rib groove of the pulley, an outer rib surface on an end side in the belt width direction at an end rib portion located at both ends in the belt width direction is provided. In the end rib grooves located at both ends in the pulley width direction, the surface pressure of the outer groove surface with which the outer rib surface abuts is set lower than the surface pressure of the other rib surface and the rib groove surface.
[0020]
According to the above configuration, by devising at least one of the end rib portion of the V-ribbed belt and the end rib groove of the V-ribbed pulley, the outer rib surface of the V-ribbed belt and the end rib of the V-ribbed pulley with which the outer rib surface abuts. The surface pressure of the outer groove surface of the groove is lower than the surface pressure of the rib surface of the other rib portion and the rib groove surface. Therefore, a belt transmission in which the effects of the present invention are remarkably exhibited can be obtained.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
(Embodiment 1)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 2 shows a belt transmission 1 according to the first embodiment of the present invention. Although not shown in detail, the belt transmission 1 drives its accessories by, for example, an engine mounted on an automobile. A drive pulley 2 attached to a crankshaft of the engine, a tension pulley 3 provided to an auto tensioner 9, and first and second auxiliary pulleys 4 and 5 attached to a rotating shaft of an auxiliary machine (not shown). . The drive pulley 2 and the first and second auxiliary pulleys 4 and 5 are both V-ribbed pulleys, while the tension pulley 3 is a flat pulley. A V-ribbed belt B is wound around these pulleys 2 to 5, and the V-ribbed belt B is rotated by the rotation of the driving pulley 2 in association with the operation of the automobile engine. The driving pulley 2 → the tension pulley 3 → the first auxiliary pulley 4 → the Each auxiliary machine is driven by traveling in the clockwise direction in FIG. 2 in the order of 2 auxiliary machine pulleys 5 → drive pulley 2.
[0022]
As shown in FIG. 1, the V-ribbed belt B includes a belt main body 10 and a back canvas layer 11 integrally formed on the upper (back) side of the belt main body 10. At the center in the longitudinal direction, core wires 12, 12,..., Which are spirally wound so as to extend substantially in the belt length direction and to be arranged at a predetermined pitch in the belt width direction, are embedded. Further, a rib rubber layer 13 is formed on the lower surface (bottom surface) side of the belt main body 10, and a plurality of rib portions 14, 14, ... each extending in the belt length direction are formed on the lower surface side of the rib rubber layer 13 in the belt width direction. They are provided integrally in a line. The rib rubber layer 13 including the respective rib portions 14 contains short fibers (not shown) in a state oriented in the belt width direction for the purpose of reinforcement or the like.
[0023]
Each rib portion 14 of the rib rubber layer 13 comes into contact with each of the V-ribbed pulleys (the driving pulley 2, the first and second auxiliary pulleys 4, 5) of the belt transmission device 1 to become a main body of power transmission, The back surface of the belt is wound around the flat tension pulley 3 so as to be in contact with the tension pulley 3 and serves as one end of power transmission.
[0024]
Hereinafter, among the V-ribbed pulleys, the first auxiliary pulley 4 in which misalignment with the V-ribbed belt B is particularly likely to occur will be described.
[0025]
As a feature of the present invention, in the V-ribbed belt B, only the ribs Pr 'between the end ribs 14a located at both ends in the belt width direction and the ribs 14 as intermediate ribs adjacent to the end ribs 14a are different from each other. The reference rib pitch Pr, which is the rib pitch between the rib portions 14, 14, is smaller (Pr ′ <Pr).
[0026]
On the other hand, the first auxiliary pulley 4 has a rib groove pitch Pg having the same interval as the reference rib pitch Pr on its outer peripheral surface so as to correspond to the reference rib pitch Pr of the rib portions 14, 14,. , And a plurality of rib grooves 20, 20,...
[0027]
When the V-ribbed belt B is wound around the first auxiliary pulley 4, and each rib portion 14 is engaged with the rib groove 20 of the first auxiliary pulley 4, the end side of each end rib portion 14a in the belt width direction. The surface pressure between the outer rib surface 14b of the first auxiliary pulley 4 and the outer groove surface 20a of the rib groove 20 of the first auxiliary pulley 4 against which the outer rib surface 14b abuts is increased by the other inner rib surface 14c and the inner groove surface of the rib groove 20. It is configured to be lower than the surface pressure with 20b.
[0028]
Next, the operation of the V-ribbed belt B according to the first embodiment of the present invention and the belt transmission 1 including the same will be described. The driving pulley 2 is rotated by the operation of the automobile engine, and the driving force is transmitted to the first auxiliary pulley 4 via the V-ribbed belt B to drive the auxiliary machine.
[0029]
At this time, as shown in FIG. 2, between the tension pulley 3 and the first auxiliary pulley 4, the center of the first auxiliary pulley 4 in the width direction and the belt drive line x are usually generated due to factors such as manufacturing errors. A misalignment y that is out of alignment occurs. When the misalignment y increases, an abnormal noise tends to occur between the V-ribbed belt B and the first auxiliary pulley 4.
[0030]
That is, conventionally, one side of each end rib portion of the V-ribbed belt is free and has no interference due to continuity with other rib portions, and thus is more easily deformed than the other rib portions. As a result, a warp occurs in which the end ribs are deformed toward the back side of the belt, and the belt tension increases in the belt width direction with the occurrence of the warp, so that the end ribs are pushed back by the belt tension. The radial force to be applied acts and slips into the end rib portion. In particular, when short fibers are contained in each rib portion, the short fibers protruding from the outer rib surface of each end rib portion are worn by this slip, and the friction coefficient of the outer rib surface increases. It is easy to get caught. As a result, a stick-slip phenomenon occurs in which the V-ribbed pulley alternately slides and adheres in the radial direction, and the slip attempts to generate abnormal noise in the belt transmission device.
[0031]
However, according to the V-ribbed belt B according to the first embodiment of the present invention, the rib pitch Pr 'between each end rib portion 14a and the intermediate rib portion 14 adjacent to the end rib portion 14a is smaller than the reference rib pitch Pr. Therefore, only the distance between the outer rib surface 14b of the end rib portion 14a and the outer groove surface 20a of the rib groove 20 abutting on the inner rib surface 14c of each of the other rib portions 14 and the inner groove surface 20b of the rib groove 20 are different. Is larger than the interval.
[0032]
For this reason, local contact of the outer rib surface 14b of each end rib portion 14a with the outer groove surface 20a of the rib groove 20 is prevented, and the outer rib surface 14b of each end rib portion 14a and the outer groove of the rib groove 20 are prevented. The surface pressure on the surface 20a is lower than the surface pressure on the other inner rib surface 14c and the inner groove surface 20b of the rib groove 20.
[0033]
Thus, deformation of each end rib portion 14a of the V-ribbed belt B can be prevented, and a radial force for pushing back the end rib portion 14a can be suppressed. Therefore, the stick-slip phenomenon in which the first auxiliary pulley 4 alternately slides and adheres in the radial direction alternately is prevented.
[0034]
Further, since the positional relationship between the inner rib surface 14c of each rib portion 14 other than the end rib portion 14b and the inner groove surface 20b of each rib groove 20 does not change, the case where the total rib pitch is smaller than the reference rib pitch Pr As described above, there is no unevenness in the surface pressure between the first auxiliary pulley and the V-ribbed belt in the portion where the pitch error overlaps in the belt width direction, and uneven wear does not occur.
[0035]
Therefore, even if misalignment y occurs between the first auxiliary pulley 4 and the V-ribbed belt B, generation of abnormal noise is suppressed.
[0036]
(Embodiment 2)
FIG. 3 shows a second embodiment of the present invention (in the following embodiments, the same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted). It differs from the first embodiment in that the shapes of 14a and 14a are different.
[0037]
Specifically, the rib pitch Pr 'between each end rib portion 14a and the rib portion 14 as an intermediate rib portion adjacent to the end rib portion 14a is equal to the reference rib pitch Pr (Pr' = Pr). . On the other hand, in each of the end ribs 14a, the distance between the outer rib surface 14b and the plane A passing through a position separated by the reference rib pitch Pr from the center position of the rib width of the rib 14 adjacent to the end rib 14a is the belt width. The distance from the plane A of the inner rib surface 14c at the center in the direction is smaller than the distance.
[0038]
That is, the inclination angle θr ′ of the outer rib surface 14b with respect to the plane A of the end rib portion 14a is the same as the inclination angle (hereinafter referred to as the reference rib angle) θr of the inner rib surface 14c of each of the other intermediate rib portions 14. (Θr ′ = θr), for example, focusing on the apex of the rib surface on the back side of the belt, the distance z in the belt width direction from the plane A to the apex of the rib surface of the outer rib surface 14b is equal to the distance z from the plane A to the inner rib surface 14c. It is smaller than the distance Pr / 2 in the belt width direction to the top of the rib surface on the back side of the belt (z <Pr / 2).
[0039]
Therefore, also in the second embodiment, similarly to the first embodiment, only the interval between the outer rib surface 14b of the end rib portion 14a of the V-ribbed belt B and the outer groove surface 20a of the rib groove 20 abutting on the other rib surface is different. The distance between the inner rib surface 14c and the inner groove surface 20b of the rib groove 20 is larger than the distance between the inner rib surface 14c and the inner groove surface 20b of the rib groove 20 without adversely affecting the contact between the other inner rib surface 14c and the inner groove surface 20b of the rib groove 20. Is obtained.
[0040]
(Embodiment 3)
FIG. 4 shows a third embodiment of the present invention, which differs from the first embodiment in that the shapes of the end ribs 14a, 14a of the V-ribbed belt B are different.
[0041]
That is, the rib pitch Pr 'of each end rib portion 14a is equal to the reference rib pitch Pr (Pr' = Pr), but the inclination angle of the end rib portion 14a of the outer rib surface 14b with respect to a plane passing through the center of the rib width (hereinafter, referred to as end rib). Θr ′) is smaller than the reference rib angle θr of the other rib portion 14 (θr ′ <θr).
[0042]
Therefore, also in the third embodiment, similarly to the first embodiment, only the distance between the outer rib surface 14b of the end rib portion 14a of the V-ribbed belt B and the outer groove surface 20a of the rib groove 20 abutting on this is different. The distance between the inner rib surface 14c and the inner groove surface 20b of the rib groove 20 is larger than the distance between the inner rib surface 14c and the inner groove surface 20b of the rib groove 20 without adversely affecting the contact between the other inner rib surface 14c and the inner groove surface 20b of the rib groove 20. V-ribbed belt B which exerts the effect of (1) is obtained.
[0043]
(Embodiment 4)
FIG. 5 shows a fourth embodiment of the present invention, which differs from the first embodiment in that the shapes of the end rib portions 14a, 14a of the V-ribbed belt B and the end rib grooves 20c, 20c at both ends of the first auxiliary pulley 4 are different. .
[0044]
That is, while the rib pitch between the rib portions 14 of the V-ribbed belt B is all equal to the reference rib pitch Pr, each end rib groove 20c of the first auxiliary pulley 4 and the intermediate rib groove adjacent to each end rib groove 20c are provided. The rib groove pitch Pg ′ between the rib grooves 20 is larger than the reference rib groove pitch Pg between the other rib grooves 20, 20 (Pg ′> Pg).
[0045]
Therefore, in the fourth embodiment, by setting only the rib groove pitch Pg ′ on the first auxiliary pulley 4 side to be larger than the reference rib groove pitch Pg, the rib portions of the V-ribbed belt B are formed in the rib grooves 20, 20,. Are engaged, the distance between the outer groove surface 20a of the end rib groove 20c of the first auxiliary pulley 4 and the outer rib surface 14b of the end rib portion 14a of the V-ribbed belt B which comes into contact therewith. Only the distance between the other inner rib surface 14c and the inner groove surface 20b of the rib groove 20 is larger. As a result, the surface pressure between the outer groove surface 20a and the outer rib surface 14b is lower than the surface pressure between the other inner groove surface 20b and the inner rib surface 14c. The first auxiliary pulley 4 with which the effect is obtained is obtained.
[0046]
(Embodiment 5)
FIG. 6 shows a fifth embodiment of the present invention, which differs from the first embodiment in that the shapes of the end rib portions 14a, 14a of the V-ribbed belt B and the end rib grooves 20c, 20c at both ends of the first auxiliary pulley 4 are different. .
[0047]
That is, the rib groove pitch Pg ′ between each end rib groove 20c of the first auxiliary pulley 4 and the intermediate rib groove 20 adjacent to the end rib groove 20c is the same as the reference rib groove pitch Pg. (Pg '= Pg). In each end rib groove 20c, an outer groove surface of the end rib groove 20c with respect to a plane A 'passing through a position separated by a reference rib groove pitch Pg from a center position of the rib groove width of the rib groove 20 adjacent to the end rib groove 20c. The distance 20a is larger than the distance from the plane A 'of the inner groove surface 20b of the rib groove 20 on the center side in the belt width direction.
[0048]
That is, the inclination angle (hereinafter, referred to as an end rib groove angle) θg ′ of the outer groove surface 20a of the end rib groove 20c with the plane A ′ is the inclination angle of the inner groove surface 20b of each of the other intermediate rib grooves 20 (hereinafter, referred to as “the end rib groove angle”). Although it is the same as θg (referred to as a reference rib groove angle) (θg ′ = θg), for example, when focusing on the apex of the groove side surface on the back side of the belt, the distance in the belt width direction from the plane A ′ to the apex of the outer groove surface 20a w is larger than the distance Pg / 2 in the belt width direction from the plane A ′ to the top of the inner groove surface 20b of the rib groove 20 on the center side in the belt width direction (w> Pg / 2).
[0049]
Therefore, in the fifth embodiment, only the outer groove surface 20a of the end rib groove 20c of the first auxiliary pulley 4 is kept away from the plane A ′, so that the outer groove surface 20a and the outer rib surface 14b of the rib portion 14 are separated. Is lower than the surface pressures of the inner groove surface 20b and the inner rib surface 14c of the other rib groove 20, so that the first auxiliary pulley 4 having the same operation and effect as the invention of the first embodiment can be obtained. Is obtained.
[0050]
(Embodiment 6)
FIG. 7 shows a sixth embodiment of the present invention, which differs from the first embodiment in that the end rib portions 14a, 14a of the V-ribbed belt B and the end rib grooves 20c, 20c at both ends of the first auxiliary pulley 4 are different. .
[0051]
That is, the inclination angle (hereinafter referred to as an end rib groove angle) θg ′ between the outer groove surface 20a of the end rib groove 20c and a plane passing through the center of the rib groove width of the end rib groove 20c is the reference rib groove angle of the other rib groove 20. It is larger than θg (θg ′> θg).
[0052]
Therefore, in the sixth embodiment, by setting only the end rib groove angle θg ′ of the end rib groove 20 c to be larger than the reference rib groove angle θg, the outer groove surface 20 a of the end rib groove 20 c and the rib portion 14 are formed. Since the surface pressure with the outer rib surface 14b is lower than the surface pressure with the inner groove surface 20b and the inner rib surface 14c of the other rib groove 20, the same operation and effect as the invention of the first embodiment can be obtained. One auxiliary pulley 4 is obtained.
[0053]
In each of the above embodiments, only the first auxiliary pulley 4 has been described as the V-ribbed pulley, but the present invention can of course be applied to other V-ribbed pulleys.
[0054]
Further, in each of the above embodiments, the shape of one of the V-ribbed belt B and the first auxiliary pulley 4 has been described, but any one of the V-ribbed belts B of the first to third embodiments or the fourth to fourth embodiments. The present invention can be applied to any belt transmission device provided with at least one of the first auxiliary pulleys 4 in any one of the first to sixth embodiments.
[0055]
【The invention's effect】
As described above, according to the V-ribbed belt of the first aspect of the invention, when the rib portion engages with the rib groove of the V-ribbed pulley, the outer rib surface on the end side in the belt width direction at the end rib portion and the outer rib. Since the surface pressure of the rib groove surface of the V-ribbed pulley with which the surface abuts is set lower than the surface pressure of the rib surface of the other rib portion and the rib groove surface, misalignment occurs between the V-ribbed pulley and the rib surface. Even so, warpage deformation of the V-ribbed belt is suppressed, and generation of abnormal noise is suppressed.
[0056]
In the invention according to claim 2, the rib pitch between the end rib portion and the intermediate rib portion adjacent to the end rib portion is smaller than the reference rib pitch. According to the third aspect of the present invention, the rib pitch between the end rib portion and the intermediate rib portion adjacent to the end rib portion is the same as the reference rib pitch, and the intermediate rib portion adjacent to the end rib portion at the end rib portion is provided. The distance of the outer rib surface to a plane passing through a position separated by the reference rib pitch from the center position of the rib width of the portion is smaller than the distance of the inner rib surface on the center side in the belt width direction to this plane. Further, in the invention of claim 4, the inclination angle between the outer rib surface of the end rib portion and a plane passing through the center of the rib width of the end rib portion is smaller than the other rib surfaces. According to these inventions, a V-ribbed belt in which the effects of the present invention are remarkably exhibited can be obtained.
[0057]
According to the V-ribbed pulley of the fifth aspect, when the rib portion of the V-ribbed belt is engaged with the rib groove, the outer groove surface on the pulley width direction end side in the end rib groove located at both ends in the pulley width direction and the outer groove surface. Since the surface pressure at the rib surface of the rib portion of the V-ribbed belt with which the side groove surface abuts is set lower than the surface pressure at the other rib groove surface and the rib surface, misalignment occurs with the V-ribbed belt. However, warpage deformation of the V-ribbed belt is suppressed, and generation of abnormal noise is suppressed.
[0058]
In the invention according to claim 6, the rib groove pitch between the end rib groove and the intermediate rib groove adjacent to the end rib groove is made larger than the reference rib groove pitch. In the invention according to claim 7, the pitch of the rib groove between the end rib groove and the intermediate rib groove adjacent to the end rib groove is the same as the reference rib groove pitch, and the end rib groove is adjacent to the end rib groove. The distance between the outer groove surface of the rib groove with respect to a plane passing through a position separated by the rib groove pitch from the center position of the rib groove width of the intermediate rib groove is larger than the inner groove surface of the rib groove on the center side in the belt width direction with respect to this plane. I made it bigger. Further, in the invention of claim 8, the inclination angle between the outer groove surface of the end rib groove and a plane passing through the center of the rib groove width of the end rib groove is made larger than the other rib groove surfaces. According to these inventions, a V-ribbed pulley in which the effects of the present invention are remarkably exhibited can be obtained.
[0059]
According to the belt transmission device of the ninth aspect, when the rib portion of the V-ribbed belt is engaged with the rib groove of the pulley, an outer rib surface at an end side in the belt width direction at an end rib portion located at both ends in the belt width direction; In the end rib grooves located at both ends in the pulley width direction, the surface pressure of the outer groove surface with which the outer rib surface abuts is set lower than the surface pressure of the other rib surface and the rib groove surface. It is possible to obtain a belt transmission in which the effect is remarkably exhibited.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a relationship between a V-ribbed belt and a V-ribbed pulley according to a first embodiment.
FIG. 2 is an overall view of a belt transmission using a V-ribbed belt and a V-ribbed pulley according to Embodiment 1 of the present invention.
FIG. 3 is a diagram corresponding to FIG. 1 showing a second embodiment.
FIG. 4 is a diagram corresponding to FIG. 1 showing a third embodiment.
FIG. 5 is a view corresponding to FIG. 1 showing a fourth embodiment.
FIG. 6 is a view corresponding to FIG. 1 showing a fifth embodiment.
FIG. 7 is a view corresponding to FIG. 1 showing a sixth embodiment.
FIG. 8 is a cross-sectional view illustrating a relationship between a V-ribbed belt and a V-ribbed pulley according to a conventional example.
[Explanation of symbols]
B V-ribbed belt
Pr Reference rib pitch
Pr 'rib pitch
Pg Standard rib groove pitch
Pg 'rib groove pitch
1 Belt transmission
4 First auxiliary pulley (V-ribbed pulley)
10 Belt body
12 core wire
14 rib
14a End rib
14b Outer rib surface
14c inner rib surface
20 rib groove
20a Outer groove surface
20b Inner groove surface
20c end rib groove

Claims

In a V-ribbed belt, a plurality of rib portions extending in a belt length direction and arranged in a belt width direction are integrally formed on a lower surface of a belt body in which a core wire is embedded,
When the rib portion engages with the rib groove of the V-ribbed pulley, the outer rib surface on the end side in the belt width direction at the end rib portion located at both ends in the belt width direction, and the rib groove of the V-ribbed pulley with which the outer rib surface abuts A V-ribbed belt characterized in that the surface pressure on the surface is set lower than the surface pressure on the other rib surface and the rib groove surface.

The V-ribbed belt according to claim 1,
A ribbed belt, wherein a rib pitch between an end rib portion and an intermediate rib portion adjacent to the end rib portion is smaller than a reference rib pitch.

The V-ribbed belt according to claim 1,
The rib pitch between the end rib portion and the intermediate rib portion adjacent to the end rib portion is the same as the reference rib pitch,
In the end rib portion, the distance between the outer rib surface and a plane passing through a position separated by the reference rib pitch from the center position of the rib width of the intermediate rib portion adjacent to the end rib portion is an inner rib on the center side in the belt width direction with respect to the plane. V-ribbed belt characterized by being smaller than the distance of the surface.

The V-ribbed belt according to claim 1,
A V-ribbed belt, wherein an inclination angle between an outer rib surface of an end rib portion and a plane passing through a center of a rib width of the end rib portion is smaller than other rib surfaces.

In a V-ribbed pulley having a plurality of rib grooves formed on an outer peripheral surface and extending in an inner peripheral direction and aligned in a pulley width direction,
When the rib portion of the V-ribbed belt is engaged with the rib groove, the outer groove surface on the pulley width direction end side of the end rib groove located at both ends in the pulley width direction, and the rib portion of the V-ribbed belt contacting the outer groove surface Wherein the surface pressure of the rib surface is set lower than the surface pressure of the other rib groove surface and the rib surface.

The V-ribbed pulley according to claim 5,
A V-ribbed pulley wherein a rib groove pitch between an end rib groove and an intermediate rib groove adjacent to the end rib groove is larger than a reference rib groove pitch.

The V-ribbed pulley according to claim 5,
The end rib groove, the rib groove pitch between the intermediate rib groove adjacent to the end rib groove is the same as the reference rib groove pitch,
In the end rib groove, the distance between the outer groove surface of the rib groove and a plane passing through a position separated by the reference rib groove pitch from the center position of the rib groove width of the intermediate rib groove adjacent to the end rib groove is a belt width relative to the plane. A V-ribbed pulley, which is larger than the inner groove surface of the rib groove on the center side in the direction.

The V-ribbed pulley according to claim 5,
A V-ribbed pulley, wherein an inclination angle between an outer groove surface of the end rib groove and a plane passing through a center of a rib groove width of the end rib groove is larger than other rib groove surfaces.

A V-ribbed belt integrally formed with a plurality of rib portions extending in the belt length direction and arranged in the belt width direction on a lower surface of the belt body in which the core wire is embedded, and a rib groove around which the V-ribbed belt is wound. A belt transmission having a V-ribbed pulley having
When the rib portion of the V-ribbed belt is engaged with the rib groove of the V-ribbed pulley, an outer rib surface at an end side in the belt width direction at an end rib portion located at both ends in the belt width direction, and an end rib groove located at both ends in the pulley width direction. , Wherein the surface pressure of the outer groove surface with which the outer rib surface abuts is set lower than the surface pressure of the other rib surface with the rib groove surface.