JP3757107B2

JP3757107B2 - Grommet

Info

Publication number: JP3757107B2
Application number: JP2000331366A
Authority: JP
Inventors: 裕幸片山
Original assignee: Yazaki Corp
Current assignee: Yazaki Corp
Priority date: 2000-10-30
Filing date: 2000-10-30
Publication date: 2006-03-22
Anticipated expiration: 2020-10-30
Also published as: JP2002142336A

Description

【０００１】
【発明の属する技術分野】
本発明は、内部に空気層（閉空間）を作り遮音効果を高めるタイプのグロメットに関する。
【０００２】
【従来の技術】
この種のグロメットとして、特開平９−２８９７２３号公報に記載のものが知られている。図３は同公報に記載されたグロメットの構成及びパネルに対する組み付け手順を示す断面図である。
【０００３】
このグロメットＧ１は、パネルＰの貫通孔Ｐａの周縁に対する嵌着溝（嵌着部）２を外周に有する大径筒部１と、パネル貫通孔Ｐａを貫通する電線（ワイヤーハーネス）Ｗが内部に通される小径筒部３と、小径筒部３の軸線方向中間部と大径筒部１の先端部とをつなぐことで大径筒部１と小径筒部３間の空間を塞ぎ、且つ、自身の弾性変形により大径筒部１に対する小径筒部３の軸線方向の変位を可能にする遮蔽壁４と、この遮蔽壁４よりも小径筒部３３の基端３ｂ側に配されて小径筒部３の外周より半径方向外方に垂直に突設された環状の遮音壁５と、大径筒部１の基端部内周に設けられた環状の係合凸部９とを備えている。
【０００４】
このグロメットＧ１を使用する場合には、まず、図３（ａ）に示すように、電線Ｗを小径筒部１の中に通した後、電線Ｗをパネル貫通孔Ｐａに貫通させる。そして、図３（ｂ）に示すように、電線Ｗを引っ張ることで小径筒部３の先端３ａをパネル貫通孔Ｐａに通すと共に、遮蔽壁４に連結した大径筒部１をパネル貫通孔Ｐａの周縁に当てる。その状態で更に電線Ｗを引っ張ると、図３（ｃ）に示すように、小径筒部３に内周部が引っ張られた形で遮蔽壁４が軸線方向に伸び、その遮蔽壁４に引っ張られながら、大径筒部１の嵌着溝２がパネル貫通孔Ｐａの周縁に嵌着する。その際、遮蔽壁４の変形により、大径筒部１に対して小径筒部３が先方に変位することになるので、それに伴って、小径筒部３の基端３ｂ側外周に形成してある遮音壁５の外周端５ａが、大径筒部１の内周に形成してある環状の係合凸部９を乗り越えて大径筒部１の内部に入り込む。
【０００５】
次いで、このように遮音壁５が大径筒部１の内部に入り込み、且つ、大径筒部１の嵌着溝２がパネル貫通孔Ｐａの周縁に嵌着したら、電線Ｗの引っ張り力を解除する。そうすると、遮蔽壁４の復元作用により、図３（ｄ）に示すように、小径筒部３が元の位置に向けて戻り、遮音壁５の外周端５ａが大径筒部１の内周の環状の係合凸部９に係合して、遮音壁５と遮蔽壁４との間に空気を閉じ込めた閉空間７が形成される。それにより、グロメットＧ１の遮音性が高められる。
【０００６】
【発明が解決しようとする課題】
ところで、図３に示した従来のグロメットＧ１は、大径筒部１の内周に環状の係合凸部９を設け、小径筒部３に軸線方向と直交する方向に突設した遮音壁５の外周端５ａを、その係合凸部９に引っ掛けることで、遮音のための閉空間７を形成するようにしているが、図３（ｄ）の閉空間７を備えた最終形状を保つためには、係合凸部９と遮音壁５とに、ある程度の剛性を持たせなくてはならない。
【０００７】
その理由は、上記のグロメットＧ１では、遮音性を保持するために遮蔽壁４の復元力によって遮音壁５を係合凸部９に密着させる構成にしているので、その復元力に打ち勝つように、遮音壁５と係合凸部９の係合状態を保っておかなければならないからである。
【０００８】
また、もう一つの理由は、図３（ｄ）の使用状態において、電線Ｗに対して横方向の力が働き、大径筒部１に対して小径筒部３が傾くような場合にも、遮音壁５が大径筒部１から外れないようにしておく必要があるからである。
【０００９】
従って、遮音壁５と係合凸部９の剛性を高くしているがゆえに、図３（ｂ）から（ｃ）に移行する過程において、つまり、係合凸部９を乗り越えて遮音壁５を大径筒部１の内部に挿入する過程において、大きな力が必要であり、大径筒部１の内部に遮音壁５を挿入しにくいという問題があった。
【００１０】
また、反対に、挿入力を小さくするために、係合凸部９や遮音壁５の剛性を落とすことも考えられるが、そうすると、係合凸部９と遮音壁５の係合が外れやすくなってしまい、外れた場合には空気層がなくなり、遮音性が保てなくなるおそれが出てくる。
【００１１】
また、図３（ｄ）の最終形状において、遮蔽壁４の復元力によって遮音壁５を係合凸部９に圧接させている（密着度を確実に保つため）ので、小径筒部３が初期位置まで完全には戻らず、図３（ａ）のパネルＰへの組み付け前と、図３（ｄ）のパネルＰに組み付けた後とで、嵌着溝２からグロメットＧ１の先端までの寸法が変わってしまうという問題もあった。つまり、組み付け前は寸法ａであったものが、組み付け後はもっと長い寸法ｂになってしまう。そうすると、予定していた位置に電線Ｗを正確に組み付けられないことになる。
【００１２】
本発明は、上記事情を考慮し、以下の課題を解決し得るグロメットを提供することを目的とする。
【００１３】
（１）小さな挿入力で遮音壁を小径筒部内に挿入することができて、遮音のための空気層（閉空間）を作ることができる。
【００１４】
（２）いったん遮音壁を小径筒部内に挿入したら、遮音壁が外れないようにすることができて、それにより確実な遮音性を保つことができる。
【００１５】
（３）パネル貫通孔にセットする前と後とで大径筒部に対する小径筒部の位置が大きく変化せず、電線の保持位置を予定通りの位置に設定することができる。
【００１６】
【課題を解決するための手段】
請求項１の発明は、パネル貫通孔の周縁に対する嵌着部を有する大径筒部と、パネル貫通孔を貫通する電線が内部に通される小径筒部と、前記小径筒部の軸線方向中間部と前記大径筒部とをつなぐことで大径筒部と小径筒部間の空間を塞ぎ、且つ、前記小径筒部の基端方向に向けて縮径する円錐壁形状に形成され、自身の外周部を支点としてその円錐壁形状の向きが逆になるように反転する自身の弾性変形により大径筒部に対する小径筒部の軸線方向の変位を可能にする遮蔽壁と、該遮蔽壁よりも小径筒部の基端側に配され、小径筒部の基端の延長方向に向けて拡径する円錐壁形状に形成されて内周端が小径筒部の外周に接合され、且つ、大径筒部に対して小径筒部をその先端方向に変位させたとき、自由端として延出する外周端が大径筒部の内周に摺接し、その状態から前記変位を解除したとき、外周端が大径筒部の内周に係合することで、前記遮蔽壁の復元作用により自身の内周部を支点にして前記初期形状と逆向きの円錐壁形状に反転し、それにより前記遮蔽壁との間に閉空間を形成する遮音壁とを備え、前記遮音壁の外周端に、大径筒部の内周に面接触することで摩擦係合する筒部を設け、この筒部の基部に、前記大径筒部に対し小径筒部が傾いたときの大径筒部の内周に対する遮音壁の外周端の変位を吸収する柔軟な変位吸収部を設けたことを特徴としている。
【００１７】
このグロメットを使用する場合には、まず、電線を小径筒部の中に通した後、電線をパネル貫通孔に貫通させる。そして、電線を引っ張ることで小径筒部の先端をパネル貫通孔に通すと共に、遮蔽壁に連結した大径筒部をパネル貫通孔の周縁に当てる。その状態で更に電線を引っ張ると、小径筒部に内周部が引っ張られた形で遮蔽壁が軸線方向に変形し、その遮蔽壁に引っ張られながら、大径筒部の嵌着部がパネル貫通孔の周縁に嵌着する。その際、遮蔽壁の変形により、大径筒部に対して小径筒部が先方に変位することになるので、それに伴って、小径筒部の基端側外周に形成してある遮音壁の外周端から筒部までが、大径筒部の内周に摺接しながら入り込む。このとき、遮音壁は、大径筒部内に入り込む方向に窄まった円錐壁形状をなしている（つまり、遮音壁の円錐壁形状の向きが大径筒部内に入り込む方向に対し順方向となっている）ので、引っ掛かり抵抗をあまり生じずに、小さな力で容易に大径筒部内に入り込ませることができる。
【００１８】
このように遮音壁が大径筒部の内周に入り込み、且つ、大径筒部の嵌着部がパネル貫通孔の周縁に嵌着したら、電線の引っ張り力を解除する。そうすると、遮蔽壁自身の復元作用により小径筒部が元の位置に戻り、それに伴って外周端が大径筒部に密着して拘束されている遮音壁は、自身の内周部を支点にして反転し、前記の初期形状と逆向きの円錐壁形状となって、遮蔽壁との間に閉じた空間を形成する。この際、遮音壁の外周端に延設した筒部が、大径筒部の内周に密着状態で摩擦係合することになるので、高い気密性が保たれる。そして、この空間が外部と遮断された空気層として機能することで、グロメットの遮音性が高められる。
【００１９】
このような使用状態において、遮音壁の外周端が大径筒部から外れるには、遮音壁が初期の円錐壁形状に反転して戻る必要があるが、いったん反転して係合した遮音壁は、外周端が大径筒部に拘束されている状態では元の円錐壁形状には戻りにくくなるので、簡単に外れなくなる。従って、確実に空気層を維持することができ、高い遮音性を確保できる。
【００２０】
また、遮音壁の形状設定によって簡単に外れにくくなることにより、反対に遮音壁の剛性を低く設定することが可能となり、そうすることで、遮音壁を大径筒部の内周にいっそう入り込ませやすくなる。つまり、小さな力でグロメットを組み付けることができるようになる。
【００２１】
また、実際の使用条件によっては、電線に横方向の力が作用することなどによって、大径筒部に対して小径筒部が傾くような場合があるが、大径筒部の内周に摩擦係合している筒部の基部には、遮音壁の外周端と大径筒部の内周との間の変位を吸収する変位吸収部があるので、その部分により傾きによる変位が吸収され、筒部と大径筒部の摩擦係合状態が維持され、閉空間が気密に保たれる。従って、遮音壁の剛性を落とした場合にも、遮音壁が外れる問題が起こらない。
【００２２】
言い換えると、遮音壁の剛性を落とすことによって、大径筒部に対する小径筒部の傾きを許せるようになるが、つまり、パネルに固定した大径筒部に対して積極的に電線を傾かせることができるようになるが、その場合であっても、遮音壁が大径筒部から外れにくくなり、遮音性を維持することができるようになる。
【００２３】
この点、図３の従来のグロメットの場合、遮音壁５と係合凸部９の剛性が高いために、電線Ｗを大径筒部１に対して傾かせることは難しく、無理に電線Ｗを傾かせると、遮音壁５と係合凸部９に大きな力が作用して係合が外れやすくなる。また、電線Ｗにも無理な力が作用することになり、好ましくない。
【００２４】
それに対し、この発明のグロメットは、パネルに対して電線を傾けて配索するような場合にも柔軟に対応することができるという長所がある。
【００２５】
また、初期形状から反転した後の遮音壁は、小径筒部の初期位置への戻り方向に窄まった円錐壁形状となる（つまり、反転後の遮音壁の円錐壁形状の向きが小径筒部の初期位置への戻り方向に対し順方向となる）ので、遮音壁による突き返し抵抗をほとんど受けることなく、小径筒部が元に位置に戻ることができる。従って、小径筒部が初期位置へ正しく戻ることで、パネルにセットする前と後のグロメット寸法に大きな変化を生じなくなる。しかも、反転して初期形状とは逆向きの円錐壁形状になった遮音壁は、自身の戻り力により大径筒部の内周面に対して密着するので、閉空間の気密性が確実に保たれる。また、このグロメットでは、電線を引っ張ることで反転した遮蔽壁が初期形状に戻るときの強い反転復元力で、小径筒部を初期位置に戻す。従って、小径筒部の引っ張り力を解除すると、強い力で小径筒部が初期位置に戻るのに引きずられて、遮音壁も一気に反転して閉空間を形成する。つまり、遮蔽壁の強い反転復元力を遮音壁を反転させる力として利用するので、ある程度まで電線を引っ張って力を加えた後は、電線の引っ張りを解除しさえすれば、自動的に正しい状態に組み付けが行われる。
【００２６】
請求項２の発明は、請求項１記載のグロメットであって、前記変位吸収部を、筒部及び遮音壁よりも肉厚の薄い薄肉筒部で構成したことを特徴としている。
【００２７】
このグロメットでは、筒部の基部に肉厚を薄くした部分を意図的に設けることにより、大径筒部に対し小径筒部が傾いた場合の遮音壁の変位を吸収することができる。
【００３０】
請求項３の発明は、請求項１または２記載のグロメットであって、前記小径筒部の基端部に、小径筒部よりも径大とされ、小径筒部に通される電線の隙間を埋めるための止水材の充填用カップ部が設けられていることを特徴としている。
【００３１】
このグロメットでは、充填用カップに溶融した止水材を入れることで、電線間の隙間を封じることができ、止水性を高めることができる。
【００３２】
請求項４の発明は、請求項１〜３のいずれかに記載のグロメットであって、前記筒部が、円筒形状に形成されていることを特徴としている。
【００３３】
このグロメットでは、電線を引っ張ることで反転した遮蔽壁が初期状態に戻るとき、遮音壁の外周端に延設された円筒形状の筒部が大径筒部の内周に均一に密着する。
【００３４】
請求項５の発明は、請求項１〜３のいずれかに記載のグロメットであって、前記筒部が、一方の開口縁が前記遮音壁の外周端に連結されて、他方の開口面積が一方の開口面積に対して大きくなっている円錐筒形状に形成されていることを特徴としている。
【００３５】
このグロメットでは、電線が引っ張られて遮音壁と共に筒部が大径筒部の内周に入り込むとき、筒部の遮音壁の外周端から外側に配置された部分が大径筒部の内周に沿って撓む。このため、電線を引っ張ることで反転した遮蔽壁が初期状態に戻るとき、筒部の撓んだ部分が自身の弾性により大径筒部の内周に密着する。
【００３６】
【発明の実施の形態】
以下、本発明の実施形態を図面に基づいて説明する。
【００３７】
図１（ａ）〜（ｃ）は、第１実施形態のグロメットＧ２の構成と同グロメットＧ２をパネルＰに取り付けるまでの手順を示す断面図である。
【００３８】
このグロメットＧ２は、パネルＰの貫通孔Ｐａの周縁に対する嵌着溝（嵌着部）３２を外周に有する大径筒部３１と、この大径筒部３１の内部に同芯に配され且つパネル貫通孔Ｐａを貫通する電線（ワイヤーハーネス）Ｗが内部に通される小径筒部３３と、小径筒部３３の軸線方向の先端３３ａと基端３３ｂの中間部と大径筒部３１の先端部とをつなぐことで大径筒部３１と小径筒部３３間の空間を塞ぎ、且つ、自身の弾性変形により大径筒部３１に対する小径筒部３３の軸線方向の変位を可能にする遮蔽壁３４と、この遮蔽壁３４よりも小径筒部３３の基端３３ｂ側に配され、小径筒部３３の基端３３ｂの延長方向に向けて拡径する円錐壁形状に形成されて、内周端３５ｂが小径筒部３３の外周に接合された遮音壁３５とを備える。
【００３９】
遮音壁３５は、大径筒部３１に対して小径筒部３３をその先端３３ａ方向に変位させたとき、自由端として延出する外周端３５ａが大径筒部３１の内周に摺接し、その状態から前記変位を解除したとき、外周端３５ａが大径筒部３１の内周に摩擦係合することで、自身の内周端３５ｂを支点にして初期形状と逆向きの円錐壁形状に反転し、それにより遮蔽壁３４との間に閉空間３７を形成するものである。
【００４０】
遮音壁３５の外周端３５ａには、大径筒部３１の内周３１ａに面接触することで摩擦係合する円筒形状の筒部４５が設けられ、この筒部４５の基部には、大径筒部３１に対し小径筒部３３が傾いたときの大径筒部３１の内周３１ａに対する遮音壁３５の外周端３５ａの変位を吸収する薄肉筒部よりなる所定長さの変位吸収部４６が設けられている。
【００４１】
筒部４５と変位吸収部４６は、遮音壁３５の外周端３５ａから、小径筒部３３の基端３３ｂの延長方向に延ばして形成されている。筒部４５の外径Ｄ２と小径筒部３１の内径Ｄ１の関係はＤ１＜Ｄ２となっている。
【００４２】
また、遮蔽壁３４は、小径筒部３３の基端３３ｂ方向に向けて縮径する円錐壁形状に形成され、且つ、自身の外周部を支点としてその円錐壁形状の向きが逆になるように反転することで、小径筒部３３の変位を許容するものとされており、この遮蔽壁３４が初期形状へ戻ろうとする復元力により、小径筒部３３を初期位置に戻して、遮音壁３５を反転させるようになっている。
【００４３】
また、小径筒部３３の基端部には、小径筒部３３よりも径大とされ、小径筒部３３に通される電線Ｗの隙間を埋める止水材Ｓを充填するための充填用カップ部３８が設けられている。
【００４４】
次に作用を説明する。
【００４５】
このグロメットＧ２を使用する場合には、まず、図１（ａ）に示すように、電線Ｗを小径筒部３３の中に通した後、溶融状態の止水材Ｓを充填用カップ部３８に充填（この工程では充填用カップ部３８を上に向ける）して、電線Ｗの隙間に止水材Ｓを行き渡らせ、硬化した止水材Ｓにより電線Ｗの隙間を埋める。そしてこの状態のグロメットＧ２付き電線Ｗの先端を、パネルＰの貫通孔Ｐａに貫通させる。次いで、電線Ｗを力Ｆで引っ張ることで、小径筒部３３の先端３３ａをパネル貫通孔Ｐａに通すと共に、遮蔽壁３４に連結した大径筒部３１をパネル貫通孔Ｐａの周縁に当てる。
【００４６】
その状態で更に電線Ｗを引っ張ると、図１（ｂ）に示すように、小径筒部３３に内周部が引っ張られた形で遮蔽壁３４が軸線方向に変形し、その遮蔽壁３４に引っ張られながら、大径筒部３１の嵌着溝３２がパネル貫通孔Ｐａの周縁に嵌着する。その際、遮蔽壁３４の変形により、大径筒部３１に対して小径筒部３３が先方に変位することになるので、それに伴って、小径筒部３３の基端３３ｂ側外周に形成してある遮音壁３５の外周端３５ａから筒部４５までが、大径筒部３１の内周に摺接しながら入り込む。
【００４７】
このとき、遮音壁３５は、大径筒部３１内に入り込む方向に窄まった円錐壁形状をなしている（つまり、遮音壁３５の円錐壁形状の向きが大径筒部３１内に入り込む方向に順方向となっている）ので、引っ掛かり抵抗をあまり生じずに、小さな力で容易に大径筒部３１内に入り込ませることができる。
【００４８】
このように遮音壁３５が大径筒部３１の内周に入り込み、且つ、大径筒部３１の嵌着溝３２がパネル貫通孔Ｐａの周縁に嵌着したら、電線Ｗの引っ張り力を解除する。そうすると、図１（ｃ）に示すように、遮蔽壁３４の復元作用により小径筒部３３が元の位置に戻ることで、筒部４５及び変位吸収部４６が大径筒部３１の内周３１ａに摩擦係合して外周端３５ａが大径筒部３１に拘束された状態にある遮音壁３５は、自身の内周端３５ｂを支点にして反転し、前記の初期形状と逆向きの円錐壁形状となって、遮蔽壁３４との間に閉空間３７を形成する。そして、この閉空間３７が外部と遮断された空気層として機能することで、グロメットＧ１１の遮音性が高められる。
【００４９】
この場合、特に遮音壁３５の外周端３５ａにある筒部４５及び薄肉円筒状の変位吸収部４６によって、遮音壁３５と大径筒部３１の密着面積が増えると共に、筒部４５が円筒形状となっているため大径筒部３１の内周３１ａに均一に密着するので、閉空間３７の気密性が高くなって、遮音性が高まる。
【００５０】
このように大径筒部３１内に入り込んで遮蔽壁３４との間に閉空間（空気層）３７を形成する遮音壁３５を、外に広がる円錐壁形状に形成しているので、大径筒部３１内に入り込ませるときに小さな力で入れることができる。また、図１（ｃ）に示すように、大径筒部３１内に入り込んで小径筒部３３が元に戻ったときには、反対向きの円錐壁形状に反転するように構成しているので、反転後は大径筒部３１から簡単に外れないようにすることができる。
【００５１】
即ち、図１（ｃ）に示す使用状態において、遮音壁３５の外周端３５ａが大径筒部３１から外れるには、遮音壁３５が初期の円錐壁形状に反転して戻る必要があるが、いったん反転して係合した遮音壁３５は、元の円錐壁形状には戻りにくくなるので、簡単に外れなくなる。従って、確実に空気層（閉空間３７）を維持することができ、高い遮音性を確保できる。
【００５２】
また、いったん反転すると外れにくくなることから、遮音壁３５の剛性を落として柔軟性を有するように薄肉に形成することが可能となり、剛性を落とすことにより、いっそう遮音壁３５を大径筒部３１内に入れやすくなる。従って、遮音壁３５を定位置に組み付けやすく、しかも、いったん組み付けると遮音壁３５が外れにくいグロメットとなる。
【００５３】
また、図１（ｃ）に示すように、遮音壁３５が初期形状から反転した後は、小径筒部３３の戻り方向に窄まった円錐壁形状になるので、小径筒部３３の戻りを妨げることがなく、小径筒部３３が初期位置へ正しく戻ることにより、パネルＰにセットする前と後でのグロメットＧ２の寸法変化をなくせる。即ち、図１（ａ）のパネルＰへの組み付け前と、図１（ｃ）のパネルＰに組み付けた後とで、嵌着溝３２からグロメットＧ２の先端までの寸法ｃ、ｄの寸法がほとんど変わらなくなる。従って、予定していた位置に、電線Ｗを正確に組み付けられるようになる。
【００５４】
また、遮音壁３５の剛性を落とすことにより、遮音壁３５の突っ張り抵抗が小さくなるので、図２に示すように、パネルＰに固定した大径筒部３１に対して電線Ｗ及び小径筒部３３を容易に傾けることができるようになる。
【００５５】
しかも、このように小径筒部３３と電線Ｗを傾けた場合でも、遮音壁３５の外周端３５ａと大径筒部３１の内周３１ａ間の変位が、筒部４５の基部に設けた薄肉筒状の変位吸収部４６によって吸収されるので、大径筒部３１の内周３１ａに対する筒部４５の密着状態が解消されることはなく、常に密着状態を保つことができて、十分な遮音性を確保することができる。
【００５６】
また、遮音壁３５は小径筒部３３の外周に一体化してあり、しかも外向きに開いた円錐壁形状に形成してあるので、小径筒部３３の基端３３ｂ側に止水材Ｓの充填用カップ部３８を設ける場合にも、金型による成形を容易に実現することができる。
【００５７】
しかも、反転して初期形状とは逆向きの円錐壁形状になった遮音壁３５は、自身の戻り力により大径筒部３１の内周３１ａに対して密着係合するので、閉空間３７の気密性が確実に保たれる。
【００５８】
また、このグロメットＧ２の場合、遮蔽壁３４の形状を遮音壁３５と逆向きの円錐壁形状に形成しており、図１（ｂ）のように電線Ｗを引っ張ることで反転した遮蔽壁３４が図１（ｃ）のように初期形状に戻るときの強い反転復元力で、小径筒部３３を初期位置に戻すようにしているので、小径筒部３３の引っ張り力を解除すると、強い力で小径筒部３３が初期位置に戻るのに引きずられて、遮音壁３５も一気に反転して閉空間３７を形成するようになる。つまり、遮蔽壁３４の強い反転復元力を、遮音壁３５を反転させる力として有効に利用することができるようにしているので、ある程度まで電線Ｗを引っ張って力を加えた後は、電線Ｗの引っ張りを解除しさえすれば、自動的に正しい状態にグロメットＧ２を組み付けることができる。
【００５９】
また、グロメットＧ２では、筒部４５が円筒形状に形成されているため、筒部４５の大径筒部３１の内周３１ａへの摩擦係合時に筒部４５が内周３１ａに均一に密着する。このため、大径筒部３１の内周３１ａと筒部４５とを確実に密着させることができ、閉空間３７の気密性を高くして、遮音性を高めることができる。
【００６０】
なお、上記実施形態では、小径筒部３３の基端部に充填用カップ部３８を設けているが、充填用カップ部３８は省略してもよい。
【００６１】
以上、実施形態について説明したが、本発明はこれに限定されるものではなく、構成の要旨に付随する各種の変更が可能である。
【００６２】
以下、本発明にかかるグロメットの変形例を説明する。この変形例の上記実施形態と相違する部分は、筒部が円錐形状に形成されていることである。
【００６３】
筒部は、一方の開口の開口縁が遮音壁３５の外周端３５ａに変位吸収部４６を介して一体成形されて連結されている。この筒部は、他方の開口面積が一方の開口面積に対して大きく形成されており、全体として肉厚が一定の円錐形状となっている。
【００６４】
上述の筒部を有したグロメットでは、上記実施形態と同様にパネルＰへの嵌着され、電線Ｗが引っ張られると遮音壁３５の外周端３５ａから筒部までが、大径筒部３１の内周３１ａに摺接しながら入り込む。このとき、筒部は、遮音壁３５の外周端３５ａから外側に配置された部分が大径筒部３１の内周３１ａに沿って内側に撓んだ状態となっている。
【００６５】
そして、電線Ｗの引っ張り力が解除されると、筒部は、大径筒部３１の内周３１ａに沿って撓んだ部分が自身の弾性により大径筒部３１の内周３１ａに当接して密着し、変位吸収部４６と共に大径筒部３１の内周３１ａに摩擦係合する。
【００６６】
上述したグロメットの変形例では、筒部の大径筒部３１の内周３１ａへの摩擦係合時に筒部の遮音壁３５の外周端３５ａから外側に配置された部分が自身の弾性により大径筒部３１の内周３１ａに当接して密着する。このため、大径筒部３１の内周３１ａと筒部との密着性が向上して遮音壁３５と遮蔽壁３４との間に形成された閉空間の気密性が高くなり、遮音性が高めることができる。
【００６７】
【発明の効果】
以上説明したように、請求項１の発明によれば、大径筒部内に入り込んで遮蔽壁との間に閉空間（空気層）を形成する遮音壁を、外に広がる円錐壁形状に形成したので、大径筒部内に入り込ませるときに小さな力で入れることができる。また、大径筒部内に入り込んで小径筒部が元に戻ったときには反対向きの円錐壁形状に反転するように構成しているので、反転後は大径筒部から外れにくくすることができる。即ち、初期形状から反転させるときには若干の力が必要になるが、いったん反転すると、外周端が大径筒部に拘束された状態では反転状態から元に戻りにくくなるので、前記閉空間を確実に保持することができ、高い遮音性を維持することができる。また、いったん反転すると外れにくくなることから、遮音壁の剛性を落とすことも可能となり、剛性を落とすことにより、いっそう遮音壁を大径筒部内に入れやすくなる。従って、遮音壁を定位置に組み付けやすく、しかもいったん組み付けると遮音壁が外れにくいグロメットを提供することができる。
【００６８】
また、遮音壁が初期形状から反転した後は、小径筒部の戻り方向に窄まった円錐壁形状になるので、小径筒部の戻りを妨げることがなく、小径筒部が初期位置へ正しく戻ることにより、パネルにセットする前と後でのグロメット寸法の変化をなくせる。従って、予測した位置に電線を正しくセットできる。
【００６９】
また、遮音壁の剛性を落とすことにより、遮音壁の突っ張り抵抗が小さくなるので、パネルに固定した大径筒部に対して電線及び小径筒部を容易に傾けることができるようになる。しかも、そのように電線及び小径筒部を傾けた場合でも、遮音壁の外周端と大径筒部の内周間の変位を、筒部の基部に設けた変位吸収部によって吸収できるので、大径筒部の内周に対する筒部の密着状態を確実に維持することができ、十分な遮音性を確保することができる。また、遮蔽壁の反転復元力を利用して遮音壁を反転させるようにしているので、組み付けが簡単、確実にできる。
【００７０】
請求項２の発明によれば、筒部の基部に肉厚を薄くした部分を意図的に設けることで、変位吸収部を形成することができるので、簡単に実現可能である。
【００７２】
請求項３の発明によれば、止水材の使用により、電線間の隙間を封じることができ、止水性を高めることができる。
【００７３】
請求項４の発明によれば、筒部を円筒形状とすることで大径筒部の内周に均一に密着させることができ、遮音壁と遮蔽壁との間に形成された閉空間の気密性を高くし、遮音性を高めることができる。
【００７４】
請求項５の発明によれば、筒部を円錐筒形状とすることで、筒部の遮音壁の外周端から外側に配置された部分を自身の弾性により大径筒部の内周に密着させる。このため、大径筒部の内周と筒部との密着性が向上し、遮音壁と遮蔽壁との間に形成された閉空間の気密性をより高くし、遮音性をより高めることができる。
【図面の簡単な説明】
【図１】（ａ）〜（ｃ）は、本発明の実施形態のグロメットの構成及び同グロメットのパネルへの組み付け手順を示す断面図である。
【図２】本発明の実施形態のグロメットの作用説明のための断面図である。
【図３】（ａ）〜（ｄ）は従来のグロメットのパネルへの組み付け手順を示す断面図である。
【符号の説明】
Ｇ２グロメット
３１大径筒部
３１ａ内周
３２嵌着溝（嵌着部）
３３小径筒部
３３ａ先端
３３ｂ基端
３４遮蔽壁
３５遮音壁
３５ａ外周端
３５ｂ内周端
３８充填用カップ部
４５筒部
４６変位吸収部
Ｓ止水材
Ｗ電線
Ｐａパネル貫通孔[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a grommet of a type that enhances the sound insulation effect by creating an air layer (closed space) inside.
[0002]
[Prior art]
As this type of grommet, a grommet described in JP-A-9-289723 is known. FIG. 3 is a cross-sectional view showing the structure of the grommet and the assembly procedure for the panel described in the publication.
[0003]
The grommet G1 includes a large-diameter cylindrical portion 1 having a fitting groove (fitting portion) 2 with respect to the periphery of the through hole Pa of the panel P and an electric wire (wire harness) W penetrating the panel through hole Pa inside. The space between the large-diameter cylindrical portion 1 and the small-diameter cylindrical portion 3 is closed by connecting the small-diameter cylindrical portion 3 that is passed through, the axially intermediate portion of the small-diameter cylindrical portion 3 and the tip of the large-diameter cylindrical portion 1; A shielding wall 4 that enables displacement of the small-diameter cylindrical portion 3 in the axial direction relative to the large-diameter cylindrical portion 1 by its own elastic deformation, and a small-diameter cylinder disposed on the proximal end 3b side of the small-diameter cylindrical portion 33 with respect to the shielding wall 4 An annular sound insulation wall 5 projecting perpendicularly outward in the radial direction from the outer periphery of the portion 3 and an annular engagement convex portion 9 provided on the inner periphery of the base end portion of the large-diameter cylindrical portion 1 are provided.
[0004]
When using this grommet G1, first, as shown in FIG. 3A, after passing the electric wire W through the small diameter cylindrical portion 1, the electric wire W is passed through the panel through hole Pa. And as shown in FIG.3 (b), while pulling the electric wire W, while passing the front-end | tip 3a of the small diameter cylinder part 3 through the panel through-hole Pa, the large diameter cylinder part 1 connected with the shielding wall 4 is made into panel through-hole Pa. Hit the edge of the. When the electric wire W is further pulled in this state, as shown in FIG. 3C, the shielding wall 4 extends in the axial direction in such a manner that the inner peripheral portion is pulled by the small diameter cylindrical portion 3, and is pulled by the shielding wall 4. However, the fitting groove 2 of the large diameter cylindrical portion 1 is fitted to the peripheral edge of the panel through hole Pa. At this time, the deformation of the shielding wall 4 causes the small-diameter cylindrical portion 3 to be displaced forward with respect to the large-diameter cylindrical portion 1, and accordingly, the small-diameter cylindrical portion 3 is formed on the outer periphery on the base end 3b side. An outer peripheral end 5 a of a certain sound insulating wall 5 gets over the annular engagement convex portion 9 formed on the inner periphery of the large diameter cylindrical portion 1 and enters the large diameter cylindrical portion 1.
[0005]
Next, when the sound insulating wall 5 enters the inside of the large-diameter cylindrical portion 1 and the fitting groove 2 of the large-diameter cylindrical portion 1 is fitted to the peripheral edge of the panel through hole Pa, the tensile force of the electric wire W is released. . Then, due to the restoring action of the shielding wall 4, the small-diameter cylindrical portion 3 returns toward the original position as shown in FIG. 3D, and the outer peripheral end 5 a of the sound-insulating wall 5 is annular on the inner periphery of the large-diameter cylindrical portion 1. A closed space 7 in which air is confined between the sound insulating wall 5 and the shielding wall 4 is formed by engaging with the engaging convex portion 9. Thereby, the sound insulation of grommet G1 is improved.
[0006]
[Problems to be solved by the invention]
By the way, the conventional grommet G1 shown in FIG. 3 is provided with an annular engaging convex portion 9 on the inner periphery of the large-diameter cylindrical portion 1, and the sound-insulating wall 5 protruding from the small-diameter cylindrical portion 3 in a direction perpendicular to the axial direction. A closed space 7 for sound insulation is formed by hooking the outer peripheral end 5a to the engaging convex portion 9, but in order to maintain the final shape provided with the closed space 7 of FIG. The engagement convex portion 9 and the sound insulation wall 5 must have a certain degree of rigidity.
[0007]
The reason is that in the grommet G1 described above, the sound insulating wall 5 is brought into close contact with the engaging convex portion 9 by the restoring force of the shielding wall 4 in order to maintain the sound insulating property, so that the sound insulating wall is overcome to overcome the restoring force. This is because the engagement state between the engagement protrusion 5 and the engagement protrusion 9 must be maintained.
[0008]
Another reason is that in the state of use of FIG. 3 (d), a lateral force acts on the electric wire W, and the small diameter cylindrical portion 3 is inclined with respect to the large diameter cylindrical portion 1. This is because it is necessary to prevent the sound insulating wall 5 from being detached from the large diameter cylindrical portion 1.
[0009]
Therefore, since the rigidity of the sound insulating wall 5 and the engaging convex portion 9 is increased, in the process of shifting from FIG. 3B to FIG. 3C, that is, over the engaging convex portion 9, the sound insulating wall 5 has a large diameter. In the process of inserting into the cylindrical portion 1, a large force is required, and there is a problem that it is difficult to insert the sound insulating wall 5 into the large diameter cylindrical portion 1.
[0010]
On the other hand, in order to reduce the insertion force, it is conceivable to reduce the rigidity of the engaging convex portion 9 and the sound insulating wall 5, but in this case, the engaging convex portion 9 and the sound insulating wall 5 are easily disengaged. When it comes off, the air layer disappears, and there is a possibility that the sound insulation cannot be maintained.
[0011]
Further, in the final shape of FIG. 3 (d), the sound insulating wall 5 is pressed against the engaging convex portion 9 by the restoring force of the shielding wall 4 (in order to ensure the close contact), so that the small diameter cylindrical portion 3 is in the initial position. The dimension from the fitting groove 2 to the tip of the grommet G1 changes before and after the assembly to the panel P in FIG. 3 (a) and after the assembly to the panel P in FIG. 3 (d). There was also a problem of end up. That is, the dimension a before assembly becomes a dimension b longer after assembly. If it does so, the electric wire W cannot be assembled | attached correctly to the position which was planned.
[0012]
In view of the above circumstances, an object of the present invention is to provide a grommet that can solve the following problems.
[0013]
(1) The sound insulation wall can be inserted into the small diameter cylindrical portion with a small insertion force, and an air layer (closed space) for sound insulation can be created.
[0014]
(2) Once the sound insulating wall is inserted into the small-diameter cylindrical portion, the sound insulating wall can be prevented from being detached, and thereby reliable sound insulating properties can be maintained.
[0015]
(3) The position of the small-diameter cylindrical portion with respect to the large-diameter cylindrical portion does not change greatly before and after being set in the panel through hole, and the holding position of the electric wire can be set to a planned position.
[0016]
[Means for Solving the Problems]
  The invention according to claim 1 is a large-diameter cylindrical portion having a fitting portion with respect to a peripheral edge of the panel through-hole, a small-diameter cylindrical portion through which an electric wire penetrating the panel through-hole is passed, and an intermediate in the axial direction of the small-diameter cylindrical portion. The space between the large-diameter cylinder part and the small-diameter cylinder part by connecting the part and the large-diameter cylinder part, andIt is formed in a conical wall shape that is reduced in diameter toward the proximal direction of the small-diameter cylindrical portion, and is inverted so that the direction of the conical wall shape is reversed with its outer periphery as a fulcrum.A shielding wall that enables the axial displacement of the small-diameter cylindrical portion relative to the large-diameter cylindrical portion by its own elastic deformation, and an extension of the proximal end of the small-diameter cylindrical portion that is disposed on the proximal end side of the small-diameter cylindrical portion relative to the shielding wall Freely when the inner peripheral end is joined to the outer periphery of the small-diameter cylindrical portion and the small-diameter cylindrical portion is displaced in the tip direction with respect to the large-diameter cylindrical portion. When the outer peripheral end extending as an end is in sliding contact with the inner periphery of the large-diameter cylindrical portion and the displacement is released from that state, the outer peripheral end is engaged with the inner periphery of the large-diameter cylindrical portion,Due to the restoring action of the shielding wallA sound insulation wall that reverses to a conical wall shape opposite to the initial shape with the inner periphery of the sound wall as a fulcrum, thereby forming a closed space between the sound insulation wall and a large outer peripheral end of the sound insulation wall is provided. A cylindrical portion that frictionally engages by contacting the inner periphery of the diameter cylindrical portion is provided, and the inner periphery of the large diameter cylindrical portion when the small diameter cylindrical portion is inclined with respect to the large diameter cylindrical portion at the base of the cylindrical portion. It is characterized by providing a flexible displacement absorbing portion that absorbs the displacement of the outer peripheral edge of the sound insulation wall with respect to the sound insulation wall.
[0017]
When using this grommet, first, the electric wire is passed through the small diameter cylindrical portion, and then the electric wire is passed through the panel through hole. And while pulling an electric wire, while passing the front-end | tip of a small diameter cylinder part through a panel through-hole, the large diameter cylinder part connected with the shielding wall is applied to the periphery of a panel through-hole. When the electric wire is further pulled in this state, the shielding wall is deformed in the axial direction in such a way that the inner peripheral part is pulled by the small diameter cylindrical part, and the fitting part of the large diameter cylindrical part penetrates the panel while being pulled by the shielding wall. Fits to the periphery of the hole. At that time, the deformation of the shielding wall causes the small-diameter cylindrical portion to be displaced forward with respect to the large-diameter cylindrical portion, and accordingly, the outer peripheral end of the sound insulating wall formed on the outer periphery on the proximal end side of the small-diameter cylindrical portion. To the cylindrical portion enters while sliding in contact with the inner periphery of the large-diameter cylindrical portion. At this time, the sound insulation wall has a conical wall shape constricted in a direction entering the large diameter cylindrical portion (that is, the direction of the cone wall shape of the sound insulation wall is a forward direction with respect to the direction entering the large diameter cylindrical portion. Therefore, it is possible to easily enter the large-diameter cylindrical portion with a small force without causing much catching resistance.
[0018]
When the sound insulation wall enters the inner periphery of the large-diameter cylindrical portion and the fitting portion of the large-diameter cylindrical portion is fitted to the peripheral edge of the panel through hole, the pulling force of the electric wire is released. Then, the small-diameter cylindrical part returns to its original position due to the restoring action of the shielding wall itself, and the sound-insulating wall whose outer peripheral end is in close contact with and constrained to the large-diameter cylindrical part is inverted with its inner peripheral part as a fulcrum. Then, a conical wall shape opposite to the initial shape is formed, and a closed space is formed between the shielding wall. At this time, since the cylindrical portion extended to the outer peripheral end of the sound insulating wall is frictionally engaged with the inner periphery of the large-diameter cylindrical portion in a close contact state, high airtightness is maintained. And since this space functions as an air layer blocked from the outside, the sound insulation of the grommet is enhanced.
[0019]
In such a state of use, in order for the outer peripheral end of the sound insulating wall to be detached from the large-diameter cylindrical portion, the sound insulating wall needs to be reversed and returned to the initial conical wall shape. However, it is difficult to return to the original conical wall shape when it is constrained by the large-diameter cylindrical portion. Therefore, the air layer can be reliably maintained and high sound insulation can be secured.
[0020]
In addition, since it becomes difficult to easily come off by setting the shape of the sound insulating wall, it is possible to set the sound insulating wall to be low in rigidity, which makes it easier for the sound insulating wall to enter the inner periphery of the large-diameter cylindrical portion. That is, the grommet can be assembled with a small force.
[0021]
Also, depending on the actual usage conditions, there may be a case where the small-diameter cylindrical portion is inclined with respect to the large-diameter cylindrical portion due to a lateral force acting on the electric wire. At the base of the engaged cylindrical part, there is a displacement absorbing part that absorbs the displacement between the outer peripheral end of the sound insulation wall and the inner periphery of the large diameter cylindrical part. The friction engagement state between the portion and the large-diameter cylindrical portion is maintained, and the closed space is kept airtight. Therefore, even when the rigidity of the sound insulation wall is reduced, the problem of the sound insulation wall coming off does not occur.
[0022]
In other words, by reducing the rigidity of the sound insulation wall, the inclination of the small diameter cylindrical portion relative to the large diameter cylindrical portion can be allowed, that is, the electric wire can be actively inclined with respect to the large diameter cylindrical portion fixed to the panel. Even in such a case, the sound insulation wall is less likely to be detached from the large-diameter cylindrical portion, and the sound insulation can be maintained.
[0023]
In this regard, in the case of the conventional grommet shown in FIG. 3, it is difficult to incline the electric wire W with respect to the large-diameter cylindrical portion 1 because the sound insulation wall 5 and the engaging convex portion 9 have high rigidity. If it is allowed, a large force acts on the sound insulating wall 5 and the engaging convex portion 9 and the engagement is easily released. Further, an unreasonable force acts on the electric wire W, which is not preferable.
[0024]
On the other hand, the grommet of the present invention has an advantage that it can flexibly cope with the case where the electric wire is inclined with respect to the panel.
[0025]
  In addition, the sound insulation wall after reversing from the initial shape has a conical wall shape constricted in the return direction to the initial position of the small diameter cylindrical portion (that is, the direction of the conical wall shape of the sound insulation wall after reversal is the initial of the small diameter cylindrical portion. Therefore, the small-diameter cylindrical portion can return to the original position with almost no back-up resistance by the sound insulation wall. Accordingly, when the small-diameter cylindrical portion is correctly returned to the initial position, the grommet dimensions before and after being set on the panel are not greatly changed. In addition, the sound insulation wall that is inverted and has a conical wall shape opposite to the initial shape is in close contact with the inner peripheral surface of the large-diameter cylindrical portion by its own return force, so that the airtightness of the closed space is reliably maintained. Be drunk.Further, in this grommet, the small-diameter cylindrical portion is returned to the initial position with a strong reverse restoring force when the shielding wall inverted by pulling the electric wire returns to the initial shape. Therefore, when the pulling force of the small-diameter cylindrical portion is released, the small-diameter cylindrical portion is dragged to return to the initial position with a strong force, and the sound insulating wall is reversed at a stretch to form a closed space. In other words, since the strong reversal restoring force of the shielding wall is used as the force to reverse the sound insulation wall, after applying the force by pulling the wire to some extent, it is automatically assembled in the correct state as long as the wire is released. Is done.
[0026]
A second aspect of the present invention is the grommet according to the first aspect, characterized in that the displacement absorbing portion is formed of a thin-walled cylindrical portion that is thinner than the cylindrical portion and the sound insulation wall.
[0027]
In this grommet, the displacement of the sound insulating wall when the small-diameter cylindrical portion is inclined with respect to the large-diameter cylindrical portion can be absorbed by intentionally providing a thinned portion at the base of the cylindrical portion.
[0030]
  Claim 3The invention ofClaim 1 or 2In the grommet described above, a base portion of the small-diameter cylindrical portion has a diameter larger than that of the small-diameter cylindrical portion, and a cup portion for filling a water-stopping material for filling a gap between electric wires passed through the small-diameter cylindrical portion. It is characterized by being provided.
[0031]
In this grommet, a gap between the electric wires can be sealed by adding a molten water-stopping material to the filling cup, and water-stopping can be increased.
[0032]
  Claim 4The invention ofClaims 1-3The grommet according to any one of the above, wherein the cylindrical portion is formed in a cylindrical shape.
[0033]
In this grommet, when the shielding wall inverted by pulling the electric wire returns to the initial state, the cylindrical cylindrical portion extended to the outer peripheral end of the sound insulating wall is in close contact with the inner periphery of the large-diameter cylindrical portion.
[0034]
  Claim 5The invention ofClaims 1-3The grommet according to any one of the above, wherein the cylindrical portion has a conical cylindrical shape in which one opening edge is connected to the outer peripheral end of the sound insulating wall and the other opening area is larger than the one opening area. It is characterized by being formed.
[0035]
In this grommet, when the electric wire is pulled and the cylinder part enters the inner periphery of the large-diameter cylindrical part together with the sound-insulating wall, the portion arranged on the outer side from the outer peripheral end of the cylindrical sound-insulating wall is along the inner periphery of the large-diameter cylindrical part. Bend. For this reason, when the shielding wall inverted by pulling the electric wire returns to the initial state, the bent portion of the cylindrical portion is in close contact with the inner periphery of the large-diameter cylindrical portion by its own elasticity.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0037]
FIGS. 1A to 1C are cross-sectional views showing the configuration of the grommet G2 of the first embodiment and the procedure until the grommet G2 is attached to the panel P. FIG.
[0038]
The grommet G2 has a large-diameter cylindrical portion 31 having a fitting groove (fitting portion) 32 with respect to the periphery of the through hole Pa of the panel P on the outer periphery, and is arranged concentrically inside the large-diameter cylindrical portion 31 and the panel. A small-diameter cylindrical portion 33 through which an electric wire (wire harness) W penetrating through the through-hole Pa passes, an intermediate portion between the axial end tip 33a and the base end 33b of the small-diameter cylindrical portion 33, and a distal end portion of the large-diameter cylindrical portion 31 Are connected to each other to block the space between the large-diameter cylindrical portion 31 and the small-diameter cylindrical portion 33 and to allow the small-diameter cylindrical portion 33 to be displaced in the axial direction with respect to the large-diameter cylindrical portion 31 by its own elastic deformation. The inner peripheral end 35b is formed in the shape of a conical wall that is arranged on the base end 33b side of the small-diameter cylindrical portion 33 with respect to the shielding wall 34 and expands in the extending direction of the base end 33b of the small-diameter cylindrical portion 33. Includes a sound insulation wall 35 joined to the outer periphery of the small diameter cylindrical portion 33.
[0039]
When the small-diameter cylindrical portion 33 is displaced in the direction of its tip 33a with respect to the large-diameter cylindrical portion 31, the sound insulating wall 35 is in sliding contact with the inner periphery of the large-diameter cylindrical portion 31, and the outer peripheral end 35a extends as a free end. When the displacement is released from the state, the outer peripheral end 35a is frictionally engaged with the inner periphery of the large-diameter cylindrical portion 31 so that the inner peripheral end 35b is used as a fulcrum and the cone shape is reversed to the initial shape. Thus, a closed space 37 is formed between the shield wall 34 and the shield wall 34.
[0040]
The outer peripheral end 35 a of the sound insulating wall 35 is provided with a cylindrical tube portion 45 that frictionally engages by surface contact with the inner periphery 31 a of the large-diameter tube portion 31. A displacement absorbing portion 46 having a predetermined length is formed of a thin cylindrical portion that absorbs the displacement of the outer peripheral end 35a of the sound insulating wall 35 with respect to the inner periphery 31a of the large diameter cylindrical portion 31 when the small diameter cylindrical portion 33 is inclined with respect to the portion 31. ing.
[0041]
The cylindrical portion 45 and the displacement absorbing portion 46 are formed to extend from the outer peripheral end 35 a of the sound insulating wall 35 in the extending direction of the base end 33 b of the small diameter cylindrical portion 33. The relationship between the outer diameter D2 of the cylindrical portion 45 and the inner diameter D1 of the small diameter cylindrical portion 31 is D1 <D2.
[0042]
Further, the shielding wall 34 is formed in a conical wall shape that is reduced in diameter toward the base end 33b of the small-diameter cylindrical portion 33, and the direction of the conical wall shape is reversed with its outer periphery as a fulcrum. By reversing, the displacement of the small-diameter cylindrical portion 33 is allowed, and by the restoring force that the shielding wall 34 tries to return to the initial shape, the small-diameter cylindrical portion 33 is returned to the initial position, and the sound insulating wall 35 is inverted. It is supposed to let you.
[0043]
Further, a filling cup for filling a base end portion of the small-diameter cylindrical portion 33 with a water stop material S that has a larger diameter than the small-diameter cylindrical portion 33 and fills a gap between the electric wires W that pass through the small-diameter cylindrical portion 33. A portion 38 is provided.
[0044]
Next, the operation will be described.
[0045]
When using this grommet G2, first, as shown in FIG. 1 (a), after passing the electric wire W through the small-diameter cylindrical portion 33, the molten water-stopping material S is put into the filling cup portion 38. Filling (in this step, the filling cup portion 38 is directed upward), the water-stopping material S is spread over the gaps of the electric wires W, and the gaps of the electric wires W are filled with the hardened water-stopping materials S. And the front-end | tip of the electric wire W with the grommet G2 of this state is penetrated to the through-hole Pa of the panel P. FIG. Next, by pulling the electric wire W with the force F, the tip 33a of the small diameter cylindrical portion 33 is passed through the panel through hole Pa, and the large diameter cylindrical portion 31 connected to the shielding wall 34 is applied to the peripheral edge of the panel through hole Pa.
[0046]
When the electric wire W is further pulled in this state, as shown in FIG. 1B, the shielding wall 34 is deformed in the axial direction so that the inner peripheral portion is pulled by the small-diameter cylindrical portion 33, and the shielding wall 34 is pulled. The fitting groove 32 of the large diameter cylindrical portion 31 is fitted to the peripheral edge of the panel through hole Pa. At that time, due to the deformation of the shielding wall 34, the small-diameter cylindrical portion 33 is displaced forward with respect to the large-diameter cylindrical portion 31, and accordingly, the small-diameter cylindrical portion 33 is formed on the outer periphery on the base end 33b side. A part from the outer peripheral end 35 a of the sound insulating wall 35 to the cylindrical part 45 enters the inner periphery of the large-diameter cylindrical part 31 while sliding.
[0047]
At this time, the sound insulating wall 35 has a conical wall shape constricted in the direction of entering the large diameter cylindrical portion 31 (that is, the direction of the conical wall shape of the sound insulating wall 35 is in the direction of entering the large diameter cylindrical portion 31). Therefore, it is possible to easily enter the large-diameter cylindrical portion 31 with a small force without causing much catching resistance.
[0048]
Thus, when the sound insulation wall 35 enters the inner periphery of the large-diameter cylindrical portion 31 and the fitting groove 32 of the large-diameter cylindrical portion 31 is fitted to the periphery of the panel through hole Pa, the pulling force of the electric wire W is released. Then, as shown in FIG. 1C, the cylindrical portion 45 and the displacement absorbing portion 46 return to the inner circumference 31 a of the large-diameter cylindrical portion 31 by returning the small-diameter cylindrical portion 33 to the original position by the restoring action of the shielding wall 34. The sound insulation wall 35 in the state in which the outer peripheral end 35a is constrained by the large-diameter cylindrical portion 31 by being frictionally engaged with the inner peripheral end 35b is inverted with its own inner peripheral end 35b as a fulcrum, and the conical wall shape is opposite to the initial shape. Thus, a closed space 37 is formed with the shielding wall 34. And the sound insulation of the grommet G11 is improved because this closed space 37 functions as an air layer cut off from the outside.
[0049]
In this case, in particular, the cylindrical portion 45 and the thin cylindrical displacement absorbing portion 46 at the outer peripheral end 35a of the sound insulating wall 35 increase the contact area between the sound insulating wall 35 and the large diameter cylindrical portion 31, and the cylindrical portion 45 has a cylindrical shape. Therefore, since it adheres uniformly to the inner periphery 31a of the large-diameter cylindrical portion 31, the airtightness of the closed space 37 is increased and the sound insulation is improved.
[0050]
In this way, the sound insulating wall 35 that enters the large diameter cylindrical portion 31 and forms a closed space (air layer) 37 with the shielding wall 34 is formed in a conical wall shape that spreads outside, so the large diameter cylindrical portion It is possible to enter with a small force when entering the 31. Further, as shown in FIG. 1 (c), when the small-diameter cylindrical portion 33 enters the large-diameter cylindrical portion 31 and returns to the original shape, it is configured to reverse to the opposite conical wall shape. Thereafter, it can be prevented from easily coming off from the large-diameter cylindrical portion 31.
[0051]
That is, in the use state shown in FIG. 1C, in order for the outer peripheral end 35a of the sound insulation wall 35 to be detached from the large diameter cylindrical portion 31, the sound insulation wall 35 needs to be reversed and returned to the initial conical wall shape. The sound insulation wall 35 engaged in this way is difficult to return to the original conical wall shape, and therefore cannot be easily detached. Therefore, the air layer (closed space 37) can be reliably maintained, and high sound insulation can be secured.
[0052]
In addition, since it becomes difficult to come off once reversed, it is possible to reduce the rigidity of the sound insulation wall 35 and to make it thin so as to have flexibility. By reducing the rigidity, the sound insulation wall 35 is further inserted into the large-diameter cylindrical portion 31. Easy to put. Therefore, the sound insulating wall 35 is easy to be assembled at a fixed position, and the sound insulating wall 35 becomes a grommet that is difficult to come off once assembled.
[0053]
Further, as shown in FIG. 1C, after the sound insulation wall 35 is reversed from the initial shape, it becomes a conical wall shape constricted in the return direction of the small diameter cylindrical portion 33, so that the small diameter cylindrical portion 33 is prevented from returning. The small-diameter cylindrical portion 33 is correctly returned to the initial position, so that the dimensional change of the grommet G2 before and after being set on the panel P can be eliminated. That is, the dimensions c and d from the fitting groove 32 to the tip of the grommet G2 are almost the same before and after assembling to the panel P of FIG. 1 (a) and after assembling to the panel P of FIG. 1 (c). It will not change. Therefore, the electric wire W can be correctly assembled at the planned position.
[0054]
Further, since the tension resistance of the sound insulation wall 35 is reduced by reducing the rigidity of the sound insulation wall 35, the electric wire W and the small diameter tube portion 33 can be easily attached to the large diameter tube portion 31 fixed to the panel P as shown in FIG. To be able to lean on.
[0055]
Moreover, even when the small-diameter cylindrical portion 33 and the electric wire W are inclined in this way, the displacement between the outer peripheral end 35a of the sound insulating wall 35 and the inner peripheral portion 31a of the large-diameter cylindrical portion 31 is a thin-walled cylindrical shape provided at the base of the cylindrical portion 45. Therefore, the close contact state of the tube portion 45 with respect to the inner periphery 31a of the large diameter tube portion 31 is not canceled, and the close contact state can always be maintained, and sufficient sound insulation is provided. Can be secured.
[0056]
Further, since the sound insulating wall 35 is integrated with the outer periphery of the small diameter cylindrical portion 33 and is formed in a conical wall shape opened outward, the water blocking material S is filled on the base end 33b side of the small diameter cylindrical portion 33. Even when the cup portion 38 is provided, molding by a mold can be easily realized.
[0057]
In addition, the sound insulation wall 35 that is inverted and has a conical wall shape opposite to the initial shape is brought into close contact with the inner periphery 31a of the large-diameter cylindrical portion 31 by its own return force. Sex is surely maintained.
[0058]
Further, in the case of this grommet G2, the shape of the shielding wall 34 is formed in a conical wall shape opposite to the sound insulation wall 35, and the shielding wall 34 inverted by pulling the electric wire W as shown in FIG. Since the small diameter cylindrical portion 33 is returned to the initial position with a strong reverse restoring force when returning to the initial shape as in 1 (c), the small diameter cylinder is released with a strong force when the pulling force of the small diameter cylindrical portion 33 is released. As the portion 33 returns to the initial position, the sound insulation wall 35 is also reversed at a stretch to form a closed space 37. That is, since the strong reversal restoring force of the shielding wall 34 can be effectively used as the force for reversing the sound insulation wall 35, after the wire W is pulled to a certain extent and the force is applied, the wire W is pulled. It is possible to automatically attach the grommet G2 to the correct state as long as it is released.
[0059]
Moreover, in the grommet G2, since the cylinder part 45 is formed in the cylindrical shape, the cylinder part 45 adheres to the inner periphery 31a uniformly at the time of friction engagement with the inner periphery 31a of the large diameter cylinder part 31 of the cylinder part 45. . For this reason, the inner periphery 31a of the large diameter cylinder part 31 and the cylinder part 45 can be made to adhere | attach reliably, the airtightness of the closed space 37 can be made high, and sound insulation can be improved.
[0060]
In the above-described embodiment, the filling cup portion 38 is provided at the proximal end portion of the small-diameter cylindrical portion 33, but the filling cup portion 38 may be omitted.
[0061]
Although the embodiment has been described above, the present invention is not limited to this, and various modifications accompanying the gist of the configuration are possible.
[0062]
Hereinafter, modifications of the grommet according to the present invention will be described. The part different from the above embodiment of this modification is that the cylindrical part is formed in a conical shape.
[0063]
The opening edge of one opening of the tube portion is integrally formed and connected to the outer peripheral end 35 a of the sound insulating wall 35 via the displacement absorbing portion 46. The cylindrical portion is formed so that the other opening area is larger than the one opening area, and has a constant conical shape as a whole.
[0064]
In the grommet having the above-described cylinder portion, when fitted to the panel P as in the above-described embodiment and the electric wire W is pulled, the outer periphery end 35a of the sound insulation wall 35 to the cylinder portion is the inner periphery of the large-diameter cylinder portion 31. It enters while sliding on 31a. At this time, the cylindrical portion is in a state in which a portion arranged outside from the outer peripheral end 35 a of the sound insulating wall 35 is bent inward along the inner periphery 31 a of the large-diameter cylindrical portion 31.
[0065]
When the pulling force of the electric wire W is released, the portion of the cylindrical portion that is bent along the inner periphery 31a of the large-diameter cylindrical portion 31 comes into contact with the inner periphery 31a of the large-diameter cylindrical portion 31 due to its own elasticity. Then, the displacement absorbing portion 46 is frictionally engaged with the inner periphery 31 a of the large diameter cylindrical portion 31.
[0066]
In the above-described modification of the grommet, the portion arranged outside from the outer peripheral end 35a of the sound insulating wall 35 of the cylindrical portion at the time of frictional engagement with the inner periphery 31a of the large diameter cylindrical portion 31 of the cylindrical portion is the large diameter cylinder due to its own elasticity. The inner periphery 31a of the part 31 is in contact with and closely contacts. For this reason, the adhesion between the inner periphery 31a of the large-diameter cylindrical portion 31 and the cylindrical portion is improved, the airtightness of the closed space formed between the sound insulating wall 35 and the shielding wall 34 is increased, and the sound insulating property is improved. Can do.
[0067]
【The invention's effect】
As described above, according to the first aspect of the present invention, the sound insulating wall that enters the large-diameter cylindrical portion and forms a closed space (air layer) with the shielding wall is formed in a conical wall shape that spreads outward. When entering the large-diameter cylindrical portion, it can be inserted with a small force. Moreover, since it is comprised so that it may invert into a conical wall shape of the opposite direction when it enters in a large diameter cylinder part and a small diameter cylinder part returns, it can make it difficult to remove | deviate from a large diameter cylinder part after inversion. That is, a slight force is required when reversing from the initial shape, but once the reversal occurs, it becomes difficult to return from the reversed state when the outer peripheral end is constrained by the large-diameter cylindrical portion. It can hold | maintain and can maintain high sound insulation. Moreover, since it becomes difficult to come off once reversed, it becomes possible to reduce the rigidity of the sound insulation wall, and it becomes easier to put the sound insulation wall into the large-diameter cylindrical portion by reducing the rigidity. Accordingly, it is possible to provide a grommet that is easy to assemble the sound insulating wall at a fixed position and that is difficult to remove once the sound insulating wall is assembled.
[0068]
In addition, after the sound insulation wall is reversed from the initial shape, it becomes a conical wall shape that is narrowed in the return direction of the small diameter cylindrical portion, so that the small diameter cylindrical portion returns correctly to the initial position without hindering the return of the small diameter cylindrical portion. This eliminates the change in grommet dimensions before and after setting on the panel. Therefore, the electric wire can be set correctly at the predicted position.
[0069]
  Moreover, since the tension resistance of the sound insulating wall is reduced by reducing the rigidity of the sound insulating wall, the electric wire and the small diameter cylindrical portion can be easily inclined with respect to the large diameter cylindrical portion fixed to the panel. Moreover, even when the electric wire and the small-diameter cylindrical portion are inclined as described above, the displacement between the outer peripheral end of the sound insulating wall and the inner periphery of the large-diameter cylindrical portion can be absorbed by the displacement absorbing portion provided at the base portion of the cylindrical portion. It is possible to reliably maintain the close contact state of the tubular portion with respect to the inner periphery of the tubular portion, and it is possible to ensure sufficient sound insulation.In addition, since the sound insulation wall is reversed using the reversal restoring force of the shield wall, the assembly can be performed easily and reliably.
[0070]
According to the second aspect of the present invention, since the displacement absorbing portion can be formed by intentionally providing the thinned portion at the base portion of the cylindrical portion, this can be easily realized.
[0072]
  Claim 3According to the invention, by using the water-stopping material, the gap between the electric wires can be sealed and the water-stopping property can be increased.
[0073]
  Claim 4According to the invention, the cylindrical portion is formed into a cylindrical shape, so that the cylindrical portion can be uniformly adhered to the inner periphery of the large-diameter cylindrical portion, and the airtightness of the closed space formed between the sound insulating wall and the shielding wall is increased. Sound insulation can be improved.
[0074]
  Claim 5According to this invention, by making the cylinder part into a conical cylinder shape, the part arranged outside from the outer peripheral end of the sound insulation wall of the cylinder part is brought into close contact with the inner periphery of the large-diameter cylinder part by its own elasticity. For this reason, the adhesion between the inner periphery of the large-diameter cylindrical portion and the cylindrical portion is improved, the airtightness of the closed space formed between the sound insulating wall and the shielding wall can be further increased, and the sound insulating property can be further increased. .
[Brief description of the drawings]
FIGS. 1A to 1C are cross-sectional views showing a structure of a grommet according to an embodiment of the present invention and a procedure for assembling the grommet to a panel.
FIG. 2 is a cross-sectional view for explaining the operation of the grommet according to the embodiment of the present invention.
FIGS. 3A to 3D are cross-sectional views showing a procedure for assembling a conventional grommet to a panel.
[Explanation of symbols]
G2 Grommet
31 Large diameter tube
31a Inner circumference
32 Insertion groove (insertion part)
33 Small diameter tube
33a Tip
33b Base end
34 Shielding wall
35 Sound insulation wall
35a Outer edge
35b Inner edge
38 Cup part for filling
45 Tube
46 Displacement absorber
S Water stop material
W electric wire
Pa Panel through hole

Claims

パネル貫通孔の周縁に対する嵌着部を有する大径筒部と、
パネル貫通孔を貫通する電線が内部に通される小径筒部と、
前記小径筒部の軸線方向中間部と前記大径筒部とをつなぐことで大径筒部と小径筒部間の空間を塞ぎ、且つ、前記小径筒部の基端方向に向けて縮径する円錐壁形状に形成され、自身の外周部を支点としてその円錐壁形状の向きが逆になるように反転する自身の弾性変形により大径筒部に対する小径筒部の軸線方向の変位を可能にする遮蔽壁と、
該遮蔽壁よりも小径筒部の基端側に配され、小径筒部の基端の延長方向に向けて拡径する円錐壁形状に形成されて内周端が小径筒部の外周に接合され、且つ、大径筒部に対して小径筒部をその先端方向に変位させたとき、自由端として延出する外周端が大径筒部の内周に摺接し、その状態から前記変位を解除したとき、外周端が大径筒部の内周に係合することで、前記遮蔽壁の復元作用により自身の内周部を支点にして前記初期形状と逆向きの円錐壁形状に反転し、それにより前記遮蔽壁との間に閉空間を形成する遮音壁とを備え、
前記遮音壁の外周端に、大径筒部の内周に面接触することで摩擦係合する筒部を設け、
この筒部の基部に、前記大径筒部に対し小径筒部が傾いたときの大径筒部の内周に対する遮音壁の外周端の変位を吸収する柔軟な変位吸収部を設けたことを特徴とするグロメット。A large-diameter cylindrical portion having a fitting portion with respect to the peripheral edge of the panel through hole;
A small-diameter cylindrical portion through which the electric wire penetrating the panel through-hole is passed,
The space between the large-diameter cylindrical portion and the small-diameter cylindrical portion is closed by connecting the intermediate portion in the axial direction of the small-diameter cylindrical portion and the large-diameter cylindrical portion, and the diameter is reduced toward the proximal direction of the small-diameter cylindrical portion. It is formed in a conical wall shape and allows its axial displacement of the small-diameter cylindrical portion relative to the large-diameter cylindrical portion by its own elastic deformation that reverses so that the direction of the conical wall shape is reversed with its outer periphery as a fulcrum. A shielding wall;
It is arranged on the base end side of the small-diameter cylindrical portion with respect to the shielding wall, is formed in a conical wall shape that expands in the extending direction of the base end of the small-diameter cylindrical portion, and the inner peripheral end is joined to the outer periphery of the small-diameter cylindrical portion. When the small-diameter cylindrical portion is displaced in the distal direction with respect to the large-diameter cylindrical portion, the outer peripheral end extending as a free end slides on the inner periphery of the large-diameter cylindrical portion, and the displacement is released from that state. When the outer peripheral end engages with the inner periphery of the large-diameter cylindrical portion, the restoring action of the shielding wall reverses to the conical wall shape opposite to the initial shape with its inner peripheral portion as a fulcrum, A sound insulation wall thereby forming a closed space with the shielding wall;
Provided at the outer peripheral end of the sound insulation wall is a cylindrical portion that frictionally engages by surface contact with the inner periphery of the large diameter cylindrical portion;
A flexible displacement absorbing portion that absorbs the displacement of the outer peripheral end of the sound insulating wall with respect to the inner periphery of the large-diameter cylindrical portion when the small-diameter cylindrical portion is inclined with respect to the large-diameter cylindrical portion is provided at the base of the cylindrical portion. Grommet.

請求項１記載のグロメットであって、
前記変位吸収部を、筒部及び遮音壁よりも肉厚の薄い薄肉筒部で構成したことを特徴とするグロメット。The grommet according to claim 1,
The grommet characterized in that the displacement absorbing portion is composed of a thin-walled tubular portion that is thinner than the tubular portion and the sound insulation wall.

請求項１または２記載のグロメットであって、
前記小径筒部の基端部に、小径筒部よりも径大とされ、小径筒部に通される電線の隙間を埋めるための止水材の充填用カップ部が設けられていることを特徴とするグロメット。The grommet according to claim 1 or 2, wherein
The base end portion of the small-diameter cylindrical portion is provided with a water-filling-filling cup portion that is larger in diameter than the small-diameter cylindrical portion and fills the gap between the wires passed through the small-diameter cylindrical portion. Grommet.

請求項１〜３のいずれかに記載のグロメットであって、
前記筒部が、円筒形状に形成されていることを特徴とするグロメット。The grommet according to any one of claims 1 to 3,
The grommet characterized in that the cylindrical portion is formed in a cylindrical shape .

請求項１〜３のいずれかに記載のグロメットであって、
前記筒部が、一方の開口縁が前記遮音壁の外周端に連結されて、他方の開口面積が一方の開口面積に対して大きくなっている円錐筒形状に形成されていることを特徴とするグロメット。The grommet according to any one of claims 1 to 3 ,
The grommet is characterized in that the cylindrical portion is formed in a conical cylindrical shape in which one opening edge is connected to the outer peripheral end of the sound insulation wall and the other opening area is larger than the one opening area. .