JP3596407B2

JP3596407B2 - Grommet, panel mounting method and mounting structure of the grommet

Info

Publication number: JP3596407B2
Application number: JP2000038802A
Authority: JP
Inventors: 善己内田
Original assignee: Sumitomo Wiring Systems Ltd
Current assignee: Sumitomo Wiring Systems Ltd
Priority date: 2000-02-16
Filing date: 2000-02-16
Publication date: 2004-12-02
Anticipated expiration: 2020-02-16
Also published as: JP2001231135A

Description

【０００１】
本発明は自動車用ワイヤハーネスに取り付けて車体パネルの貫通穴に装着するグロメットおよび、該グロメットのパネルへの取付方法とパネル取付構造に関するものである。
【０００２】
【発明の属する技術分野】
従来より、自動車のエンジンルームから車室内へとワイヤハーネスを配索する場合、図８および図９に示すように、ワイヤハーネスＷ／Ｈにゴムあるいはエラストマー製のグロメット１を外嵌している。このグロメット１を取り付けたワイヤハーネスＷ／Ｈを、エンジンルーム（Ｘ）と車室（Ｙ）とを仕切る車体パネル２の貫通穴３に通して、上記グロメット１を貫通穴３の周縁に装着して、エンジンルーム側から車室へ貫通孔３を通して水や埃等が浸入することを防止する防水性、防塵性を持たせている。
【０００３】
上記グロメット１はワイヤハーネスＷ／Ｈを密嵌状態で挿通させる小径筒部１ａと、該小径筒部１ａの一端より円錐筒形状に連続する拡径筒部１ｂを備え、該拡径筒部１ｂの外周面に車体係止用の凹部１ｃを環状に設けている。この凹部１ｃを車体パネル２の貫通穴３に嵌合して、グロメット１を車体パネル２に取り付けており、この取付時における係止力を高めるため、車体係止用凹部１ｃを設けた部分は厚肉とすると共に凹部１ｃを深くしている。
【０００４】
上記グロメット１は、従来、図９に示すように、エンジンルーム（Ｘ）から貫通穴３を通して車室（Ｙ）へと、拡径筒部１ｂ側から挿入し、貫通穴３の内径Ｄよりも大きい凹部１ｃを挟む両側外周部を押し潰しながら、グロメット１の全体を車室（Ｙ）へと一旦押し込んでいる。その後、ワイヤハーネスＷ／Ｈをエンジンルーム（Ｘ）側から引き戻して凹部１ｃを貫通穴３に嵌合して、グロメット１を車体パネル２に取り付けている。即ち、エンジンルーム（Ｘ）から車室（Ｙ）へと一旦押し込んだ後にエンジンルームへと引き戻す２動作でグロメット１の車体パネル２への取付を行っている。このように一旦押し込んだ後に再度引き戻して凹部１ｃを車体パネル２に嵌合させているのは、突出量の大きな周壁１ｅより押し込むと、突出量の小さい周壁１ｆとの間の凹部１ｃに貫通穴３の周縁を節度感良く確実に嵌合できないことによる。
【０００５】
【発明が解決しようとする課題】
近時、自動車に搭載する部品の急増に伴い、上記グロメット１を取り付ける車体パネル２の両側近傍にも部品が配置されている。前記のように、グロメット１を車体パネル２に取り付ける時、まず、エンジンルーム側から車室内にグロメット１の全体を押し込むが、車室内において押し込まれたグロメットを受け入れるスペースを確保することが困難になってきている。また、グロメットを車室内に押し込んだ後にエンジンルーム側に引き戻しているが、エンジンルーム側においても、ワイヤハーネスＷ／Ｈを持ってエンジンルーム側へ引き戻す作業ができるスペースがなくなってきている。また、スペースの減少に伴い従来のグロメットは、それ自体の長さを短くすることが要望されている。
【０００６】
本発明は上記した問題に鑑みてなされたもので、エンジンルーム側からの押し込みの１動作でグロメットを車体パネルの貫通孔に確実に挿入係止できる構成とし、かつ、グロメット自体の長さも短くできるようにしたグロメットを提供することを課題としている。
【０００７】
【課題を解決するための手段】
上記課題を解決するため、本発明は、自動車用ワイヤハーネスに外装した状態で車体パネルの貫通穴に挿入係止するグロメットであって、
ゴムまたはエラストマーからの成型品からなり、ワイヤハーネスを密嵌状態で挿通させる小径筒部と、該小径筒部の一端より連続する大径筒部とを備え、該大径筒部より上記貫通穴に挿入するようにしており、
上記大径筒部は貫通穴挿入側先端より折り返して内筒と外筒とからなる二重筒形状とし、
上記内筒外周面より第１環状突起と第２環状突起とを突設し、外筒内周面に形成する係止溝内に上記第１環状突起と第２環状突起とを挿入係止して、内筒と外筒とを折り返し状態で保持すると共に、記第１環状突起と第２環状突起との間にＶ形状の密閉された空間と、貫通孔挿入端側の内筒と外筒との間に密閉された空間との２つの密閉空間を形成し、
かつ、上記外筒の上記係止溝を形成した位置の外周面に車体係止用の凹部を形成し、該凹部の貫通穴挿入側の前側壁を後側壁側へと傾斜させて突出させると共にその突出高さを低くして、凹部内に倒れ込めるように設定していることを特徴とするグロメットを提供している。
【０００８】
上記のように、本発明のグロメットでは、車体係止用の凹部の貫通穴挿入側の側壁を傾斜させると共に高さを低くし、かつ、凹部の内方側に係止溝を設けて内方への変形可能としていることより、貫通穴への挿入時に側壁が押圧されると内方へ変形すると共に凹部に倒れ込んで、貫通穴を通過させることができる。通過後には側壁が原状に復帰して突出し、他方の側壁との間の凹部に車体パネルを嵌合して、グロメットを押し込みだけの１動作でパネルに取り付けることができる。このように、押し込み時の操作力をさほど要求されず、パネルの取付作業性を改善することができる。さらに、グロメットには内筒と外筒との間に密閉された空間が形成されているため、該空間で振動音等の騒音を低減でき、遮音性能も高めることができる。
【０００９】
具体的には、エンジンルーム側から車室側へと車体パネルに設けたバーリング付きの貫通穴に、グロメットを押し込みだけの１動作で取り付けている。よって、エンジンルーム側および車室側のいずれにもスペースがない場合であっても、車体パネルへのグロメットの取付作業を問題なく行うことができる。
【００１０】
上記環状突起は、内筒外周面の小径筒部側に近接した位置より突設し、該内筒の先端から折り返して形成する外筒に車体係止用の凹部を設け、該凹部の内周側に形成した形成溝に上記環状突起を挿入係止して外筒を保持するため、車体係止用の凹部は小径筒部に近接した位置となり、グロメットの軸線方向の全長を短くすることができる。
【００１１】
また、上記貫通穴挿入側先端の密閉空間を囲む内筒と外筒の肉厚を薄くすると共に、該薄肉な部分に連続して上記車体係止用の凹部の傾斜した前側壁を突設する一方、後側壁は厚肉としている。該構成とすることにより、パネル貫通穴への挿入力をより小さくできると共に、貫通穴への挿入後の係止力を強くすることができる。また、上記厚肉とした後側壁の先端より傾斜した側壁へと突出するリップを設けておくと、該リップが車体パネルに密着して、防水性能を高めることができる。
【００１２】
上記環状突起のうち、小径筒部側の第１環状突起を小径筒部側へと傾斜させて形成している。なお、環状突起は上記のように分割することが好ましいが、分割せずに１つの環状突起としておいてもよい。
【００１３】
上記のように環状突起を分割すると、その間に密閉空間を形成でき、この空間でも伝導される騒音を低減でき、貫通孔挿入側の密閉空間と合わせて２つの密閉空間を形成できることより遮音性能を高めることができる。また、グロメットを車体パネルの貫通孔に挿入係止する操作時において、第１と第２の環状突起の間の空間に車体係止用の凹部底面が凹部の底面が入り込むように変形させることができ、この点からもグロメットの貫通孔への挿入力を低くすることができる。また、小径筒部側の第１環状突起を傾斜させているため、小径筒部側への引っ張り力が作用した時に、第１環状突起が軸線直角方向に変位し、外筒側の係止溝から離脱せず、外筒を折り返し状態に確実に保持しておくことができる。
【００１４】
上記グロメットが取り付けられる車体パネルには、グロメット挿入側と反対側の一面にサイレンサー部材が取り付けられていると共に、該サイレンサー部材の表面に表皮が貼着されている。サイレンサー部材には車体パネルの貫通穴と連通する貫通穴が形成されていると共に表皮には一回り小さい貫通穴が形成されており、該表皮の貫通孔の周縁は、グロメットの大径筒部先端の密閉空間を囲む外筒に撓んだ状態で圧接され、より遮音性能を高めることができる。
【００１５】
上記表皮には、通常、貫通孔の周縁から放射状にスリットをいれてグロメットの外周面に密着させるようにしているが、該表皮の貫通穴周縁と接する部分のグロメットは、薄肉の外筒と内筒で密閉空間を囲む構成としているため、グロメット自体も可撓性を備え、表皮にスリットを形成しなくとも、グロメットを表皮の貫通孔に通して表皮をグロメット外周面に密着させることができる。このように、表皮にスリットを設けない構成とすると、遮音性能をより高めることができる。
【００１６】
【発明の実施の形態】
以下、本発明の実施形態を図面を参照して説明する。
図１乃至図５は第１実施形態を示し、グロメット１０はゴムまたはエラストマーからなり、ワイヤハーネスＷ／Ｈを密嵌状態で挿通させる小径筒部１１と、小径筒部１１の一端より連続する大径筒部１２とを備えた形状からなり、該大径筒部１２は図１に示すように、内筒１４と外筒１５とからなる二重筒構造としているが、成形時には、図２に示すように小径筒部１１に内筒１４を連続させ、該内筒１４の先端に外筒１５を連続させ、外筒１５を折り返して内筒１４と形成させて、大径筒部１２を図１に示すような二重筒形状としている。
【００１７】
小径筒部１１の一端外周より径方向に突出させた閉鎖壁部１３の外周より上記内筒１４を設け、該内筒１４の小径筒部側の後端に近接した位置に、第１環状突起１８と第２環状突起１９とをＶ形状の空間２０をあけて突設している。後端側の第１環状突起１８は軸線Ｌに対して後方に傾斜させている。第２環状突起１９の前端面１９ａは基部１９ａを前方へと傾斜させると共に、突出部１９ｂを軸直角方向としている。これら第１環状突起１８の後端位置から第２環状突起１９の前端位置までの長さをＬ１としている。
【００１８】
図２に示す成形状態で、内筒１４の前端から薄肉筒部２１を前方へと延在させ、該薄肉筒部２１の前端を後方へと折り返して、厚肉とした車体係止部２２を設けている。上記薄肉筒部２１は、その長さ方向の略中央部が折り返して、図１に示す形状としており、薄肉筒部２１の後側部分が内筒１４の前部薄肉部分２１ａとなり、薄肉筒部２１の前側部分が外筒１５の前部薄肉部分２１ｂとなり、その間に空間２４が形成されることとなる。また、薄肉筒部２１と内筒１４との連続部の内面にはリブ２９を設けている。
【００１９】
上記外筒１５の前部薄肉部分２１ｂに連続する車体係止部２２には、その内周面に係止溝２６を設けている。該係止溝２６は図１に示す折り返し状態で上記第１環状突起１８と第２環状突起１９と対応した位置となり、その前後方向の長さをＬ２とし、Ｌ２≦Ｌ１に設定している。上記係止溝２６内に第１環状突起１８と第２環状突起１９とを圧入して、第１環状突起１８の先端面１８ａを係止溝２６の溝底面２６ａに圧接すると共に、係止溝２６の後端面２６ｂに第１環状突起の先端エッジ１８ｂを係止している。また、第２環状突起１９の先端面１９ｃを溝底面２６ａに圧接すると共に、係止溝２６の前端面２６ｃに突出部１９ｂを圧接している。このように、第１、第２環状突起１８、１９を係止溝２６に圧入することにより、内筒１４の外側に折り返し状態で外筒１５を固定することができる。
【００２０】
上記のように第１環状突起１８と第２環状突起１９を係止溝２６内に挿入して圧接することにより、第１環状突起１８と第２環状突起１９との間の空間２０が密閉さえると共に、薄肉部分２１を折り返して形成した上記空間２４も密閉されることとなる。
【００２１】
上記外筒１５を構成する車体係止部２２の外周面には、凹部２８を形成し、貫通孔挿入側となる凹部の前側壁３０を他側の後壁壁３１側へと傾斜させ、かつ、該前側壁３０の突出高さを後側壁３１よりも低くして、凹部２８内に倒れ込めるように設定している。また、凹部２８の底面２８ａは略山形状として、その前後両側を側壁側へ若干切り込むように形成している。
【００２２】
このように、本グロメット１０は、車体係止部２２を小径筒部１１に近接した位置に設け、大径筒部１２の長さを従来のグロメットと比較して略２／３〜１／２程度と短くしている。
【００２３】
上記形状としたグロメット１０は、図３に示すように、小径筒部１１を拡げ治具（図示せず）を用いて拡げた状態でワイヤハーネスＷ／Ｈを貫通させ、大径筒部１２の前端開口より引き出し、小径筒部１１の先端とワイヤハーネスＷ／Ｈとにテープ３５を巻き付けて固定している。その後、グロメット１０の内部に２液シール剤を充填しており、その際にリブ２９はシール剤の剥がれを防止する作用をする。なお、シール剤は充填しなくともよい。
【００２４】
グロメット１０を取り付けたワイヤハーネスＷ／Ｈを自動車に配索する時、図４（Ａ）（Ｂ）（Ｃ）に示すように、エンジンルーム（Ｘ）から車体パネル２の貫通穴３を通して車室（Ｙ）へと貫通させる。該貫通穴３の周縁にはバーリング３ａがエンジンルーム（Ｘ）に向かって突出している。また、車体パネル２の室内側には、サイレンサー４０が取り付けられ、該サイレンサー４０に貫通穴３と略同径の貫通穴４１があけられている。サイレンサー４０の表面にはさらに樹脂シート等からなる表皮４２が取り付けられており、該表皮４２は貫通穴４１より一回り小さい貫通穴４３があけられている。この貫通穴４３の周縁には、従来は放射状にスリットが設けられているが、本発明のグロメット１０を取り付ける表皮４２はスリットを設けていない。
【００２５】
ワイヤハーネスＷ／Ｈに取り付けたグロメット１０は、図示のように、密閉空間２４を囲む薄肉部分２１ａ、２１ｂからなる大径筒部前端Ｆより、車体パネルの貫通穴３へと押し込んで挿入していく。この挿入時、前端Ｆの直径Ｄ１は車体パネル２の貫通穴３およびサイレインサー４０の貫通穴４１の直径Ｄ２よりも小さいために簡単に挿通する。サイレインサー４０の表皮４２の貫通穴４３の直径Ｄ３はグロメット１０の前端直径Ｄ１よりも小さく設定しているため、表皮の貫通穴周縁がグロメット１０の外筒の薄肉部分２１ｂの外周面に前方へ撓みながら密着する。このとき、薄肉部分２１ｂの内部は空間２４であるため薄肉部分２１ｂも容易に撓むことができ、表皮の貫通穴周縁にスリットを入れていなくても、貫通穴周縁をグロメット外周面に変形させて密着させることができる。
【００２６】
一方、貫通穴３よりエンジンルーム（Ｘ）側に突出しているバーリング３ａが車体係止部２２の傾斜した前側壁３０に達すると、バーリング３ａにより前側壁３０を内側へと押さえる。グロメット１０をされに押し込んでいくことにより、図４（Ｂ）に示すように、バーリング３ａに押されて前側壁３０が後方の凹部２８内に倒れ込む。この時、凹部２８の底面２８ａは第１環状突起１８と第２環状突起１９の間の空間２０へと割り込むように変形し、前側壁３０の小径化を促進する。このようにして、バーリング３ａが前側壁３０を低い操作力で乗り越えさせることができ、大きな操作力を要せずに、貫通穴３およびバーリング３ａに前側壁３０を通すことができる。
【００２７】
前側壁３０がバーリング３ａの先端より外れると、前側壁３０は原状に復帰して外方に突出した状態となり、バーリング３ａおよび貫通穴３の周縁のパネル２は前側壁３０と後側壁３１との間に嵌まり込んだ状態となり、凹部２８に係止される。このとき、前側壁３０は後側壁３１側へと傾斜させているため、パネル２の室内面側に密着する。
【００２８】
上記のように、ワイヤハーネスＷ／Ｈに取り付けたグロメット１０をエンジンルーム側から押し込むだけの１動作でグロメット１０を貫通穴３に通して係止することができる。よって、従来の押し引きの２動作と比較してグロメットの取付作業が簡単になると共に、車室内およびエンジンルーム側にスペースが無くともグロメットの取付を問題なく行うことができる。
【００２９】
また、グロメット１０には密閉された２つの空間２０、２４があるため、エンジンルーム側から室内側へと侵入する騒音が空間２０、２４で減衰され、遮音性能を高めることができる。また、サイレインサー４０の表皮４２の貫通穴周縁にスリットを入れていないことにより、スリットを通して音が漏れることも防止でき、より遮音性能を高めることができる。
【００３０】
上記グロメット１０を車体パネル２に取り付けた状態で、ワイヤハーネスＷ／Ｈにエンジンルーム（Ｘ）側へ引っ張る時あるいは引っ張り方向の外力が作用した時、図５（Ａ）に示すように、第１環状突起１８がグロメット１０に対して軸直角方向となる。よって、内筒１４と外筒１５との係止保持力がより高まるため、防水機能を保持できると共に、係止溝２６と環状突起１８、１９とが離脱することを防止でき、車体パネル２からグロメット１０が抜けるのを確実に防止できる。
【００３１】
また、グロメット１０を図５（Ｂ）で示すように、エンジンルーム側の他部品との関係より３０度程度曲げてグロメット１０を貫通穴３に挿入せざるを得ない場合もある。その場合、図示の上側では第２環状突起１９が係止溝２６の前端面２６ｃに当接係止されると共に、下側では第１環状突起１８が係止溝２６の後側面２６ｂに当接係止される。よって、グロメットが傾いても防水性能を確保できると共に、環状突起１８、１９が係止溝２６から外れることはない。
【００３２】
図６は第１実施形態の変形例を示し、下記の点を変えている。
▲１▼係止溝２６の前端面２６ｃ’を後方へ傾斜させたテーパ面としている。このように、テーパ面とすることにより、押し込み時における係止突起１９’を移動を防止している。
▲２▼係止突起１９’の前端面１９ｂ’に段差を付けずに大きな円弧形状に連続させている。このように連続させて凹みを無くしていることにより係止突起１９’の強度を保持している。
【００３３】
図７（Ａ）（Ｂ）は参考実施形態をしめす。該参考実施形態のグロメット１０’では、内筒１４に設ける環状突起を分割せずに１つの環状突起５０から形成している。さらに、外筒１５の車体係止凹部２８の後側壁３１に前方へ突出するリップ５１を設けている。該リップ５１の先端は前側壁３０よりも更に前方まで突出させ、グロメット１０’を車体パネル２に取り付けた状態で、車体パネルのエンジンルーム側の面にリップ５１を圧接させるようにしている。他の構成は第１実施形態と同様であるため、同一符号を付して説明を省略する。
【００３４】
【発明の効果】
以上の説明より明らかなように、本発明に係わるグロメットでは、車体係止用の凹部の貫通孔挿入側の前側壁の高さを低くすると共に後側壁へと傾斜させ、該前側壁から車体パネルの貫通穴に押し込むと、前側壁が容易に縮径して貫通穴を通り、グロメットのパネル取付作業を容易とすることができる。このように、グロメットを押し込むだけの１動作で車体パネルの貫通穴に係止できることより、グロメット取付位置の近傍にスペースがない場合においても、グロメットの取付をスムーズに行うことができる。また、グロメットを押し込むだけでよいため、グロメットの取付作業性を改善することができる。
【００３５】
また、貫通孔挿入側の先端に薄肉部で囲まれた密閉空間を設けているため、遮音性能を高めることができる。特に、第１環状突起と第２環状突起との間にも密閉空間を設けると、グロメット内部に２つの密閉空間を形成できるため、遮音性能に優れたグロメットとすることができる。
【００３６】
さらに、大径筒部を折り返して形成し、車体係止部を小径筒部に近接した位置に配置しているため、グロメットの全長を短くできる。よって、グロメットの配置スペースを小さくできる。かつ、グロメットが少し斜めに車体パネルに取り付けられても防水性能を確保することができる利点等、種々の利点を有するものである。
【図面の簡単な説明】
【図１】本発明の第１実施形態のグロメットの断面図である。
【図２】上記グロメットの成形時の断面図である。
【図３】上記グロメットにワイヤハーネスを取り付けた状態の断面図である。
【図４】（Ａ）（Ｂ）（Ｃ）は上記ワイヤハーネスに取り付けたグロメットを車体パネルの貫通穴に通して係止する工程を示す図面である。
【図５】（Ａ）はグロメットがエンジンルーム側に引っ張られた時の断面図、（Ｂ）はグロメットが若干曲げられて取り付けられた時の断面図である。
【図６】第１実施形態の変形例を示す断面図である。
【図７】参考実施形態を示し、（Ａ）は第２実施形態のグロメットの断面図、（Ｂ）は成形時の断面図である。
【図８】従来のグロメットを示す断面図である。
【図９】（Ａ）乃至（Ｃ）は従来のグロメットを車体パネルの貫通穴に挿入係止する工程を示す図面である。
【符号の説明】
２車体パネル
３貫通穴
３ａバーリング
１０グロメット
１１小径筒部
１２大径筒部
１４内筒
１５外筒
１８第１環状突起
１９第２環状突起
２０密閉空間
２１（２１ａ、２１ｂ）薄肉部分
２２車体係止部
２４密閉空間
２６係止溝
２８凹部
３０傾斜した前側壁
３１後側壁
４０サイレンサー
４２表皮
Ｗ／Ｈワイヤハーネス[0001]
The present invention relates to a grommet which is attached to a wire harness for an automobile and is attached to a through hole of a vehicle body panel, a method of attaching the grommet to a panel, and a panel attachment structure.
[0002]
TECHNICAL FIELD OF THE INVENTION
2. Description of the Related Art Conventionally, when a wire harness is routed from an engine room of an automobile to a vehicle interior, a grommet 1 made of rubber or an elastomer is externally fitted to the wire harness W / H as shown in FIGS. The wire harness W / H to which the grommet 1 is attached passes through the through hole 3 of the vehicle body panel 2 that separates the engine room (X) and the vehicle room (Y), and the grommet 1 is attached to the periphery of the through hole 3. In addition, waterproof and dustproof properties are provided to prevent water, dust and the like from entering the vehicle compartment from the engine room side through the through holes 3.
[0003]
The grommet 1 includes a small-diameter tube portion 1a through which the wire harness W / H is inserted in a tightly-fitted state, and a large-diameter tube portion 1b continuous from one end of the small-diameter tube portion 1a in a conical tube shape. A concave portion 1c for locking the vehicle body is provided in an annular shape on the outer peripheral surface of the vehicle. The recess 1c is fitted into the through hole 3 of the vehicle body panel 2, and the grommet 1 is mounted on the vehicle body panel 2. In order to increase the locking force at the time of mounting, the portion provided with the vehicle body locking recess 1c The recess 1c is made thicker and deeper.
[0004]
Conventionally, as shown in FIG. 9, the grommet 1 is inserted from the engine room (X) through the through hole 3 into the vehicle interior (Y) from the side of the large-diameter tube portion 1 b, The entire grommet 1 is once pushed into the vehicle interior (Y) while crushing both outer peripheral portions sandwiching the large concave portion 1c. Thereafter, the wire harness W / H is pulled back from the engine room (X) side, the concave portion 1c is fitted in the through hole 3, and the grommet 1 is mounted on the vehicle body panel 2. That is, the grommet 1 is mounted on the vehicle body panel 2 by two operations of once pushing the engine from the engine room (X) into the vehicle room (Y) and then returning the grommet 1 to the engine room. The reason why the recess 1c is fitted to the vehicle body panel 2 by being pushed in once and then pulled back again because the recess 1c is pushed in from the peripheral wall 1e having a large protrusion amount is formed in the concave portion 1c between the peripheral wall 1f having a small protrusion amount. This is because the periphery of No. 3 cannot be securely fitted with a sense of moderation.
[0005]
[Problems to be solved by the invention]
Recently, with the rapid increase in the number of components mounted on an automobile, components are also arranged near both sides of the vehicle body panel 2 on which the grommet 1 is mounted. As described above, when attaching the grommet 1 to the vehicle body panel 2, first, the entire grommet 1 is pushed into the vehicle interior from the engine room side, but it is difficult to secure a space for receiving the grommet pushed in the vehicle interior. Is coming. Further, although the grommet is pushed back into the vehicle compartment and then pulled back to the engine room side, there is no longer any space on the engine room side where it is possible to carry the wire harness W / H back to the engine room side. In addition, as the space is reduced, the conventional grommet has been demanded to reduce its length.
[0006]
The present invention has been made in view of the above-described problem, and has a configuration in which a grommet can be reliably inserted and locked in a through hole of a vehicle body panel by one operation of pushing from the engine room side, and the length of the grommet itself can be shortened. It is an object to provide such a grommet.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is a grommet that is inserted and locked in a through hole of a vehicle body panel in a state where the grommet is mounted on an automobile wire harness,
A small-diameter cylindrical portion made of a molded product made of rubber or elastomer, through which the wire harness is inserted in a tightly fitted state, and a large-diameter cylindrical portion continuous from one end of the small-diameter cylindrical portion, wherein the large-diameter cylindrical portion has a through hole. To be inserted into
The large-diameter cylindrical portion is folded from the end of the through-hole insertion side to form a double cylindrical shape including an inner cylinder and an outer cylinder,
A first annular projection and a second annular projection are protruded from the outer peripheral surface of the inner cylinder, and the first annular projection and the second annular projection are inserted and locked in locking grooves formed on the inner peripheral surface of the outer cylinder. The inner cylinder and the outer cylinder are held in a folded state, and a V-shaped sealed space is provided between the first annular projection and the second annular projection, and the inner cylinder and the outer cylinder at the through-hole insertion end side. To form two sealed spaces with a closed space,
In addition, a concave portion for locking the vehicle body is formed on the outer peripheral surface of the outer cylinder at a position where the locking groove is formed, and the front side wall of the concave portion on the side where the through hole is inserted is inclined and protruded toward the rear side wall, and The grommet is characterized in that its protruding height is set low so that it can fall down into the recess.
[0008]
As described above, in the grommet of the present invention, the side wall on the through hole insertion side of the vehicle body locking recess is inclined and the height is reduced, and the locking groove is provided on the inner side of the recess to form When the side wall is pressed at the time of insertion into the through hole, the side wall is deformed inward and falls down into the concave portion so that it can pass through the through hole. After passing, the side wall returns to its original shape and protrudes, and the vehicle body panel is fitted into the recess between the other side wall, and the grommet can be attached to the panel by one operation of pushing in only. As described above, the operation force at the time of pushing is not so required, and the workability of mounting the panel can be improved. Furthermore, since a closed space is formed between the inner cylinder and the outer cylinder in the grommet, noise such as vibration noise can be reduced in the space, and sound insulation performance can be improved.
[0009]
Specifically, the grommet is attached to the through-hole with burring provided in the vehicle body panel from the engine room side to the vehicle room side by one operation of only pushing the grommet. Therefore, even when there is no space on either the engine room side or the vehicle room side, the work of attaching the grommet to the vehicle body panel can be performed without any problem.
[0010]
The annular projection is provided so as to protrude from a position close to the small-diameter cylindrical portion of the outer peripheral surface of the inner cylinder, and a concave portion for locking the vehicle body is provided on an outer cylinder formed by folding back from a tip of the inner cylinder. Since the annular projection is inserted and locked in the formed groove formed on the side and the outer cylinder is held, the concave portion for locking the vehicle body is located at a position close to the small-diameter cylindrical portion, and the overall length of the grommet in the axial direction can be shortened. it can.
[0011]
Further, the thickness of the inner cylinder and the outer cylinder surrounding the sealed space at the end of the through hole insertion side is reduced, and the slanted front side wall of the vehicle body locking recess is continuously provided to the thin portion. On the other hand, the rear wall is thick. With this configuration, the insertion force into the panel through hole can be further reduced, and the locking force after insertion into the through hole can be increased. In addition, if a lip is provided that protrudes from the tip of the thick rear wall to the side wall that is inclined, the lip comes into close contact with the vehicle body panel, and the waterproof performance can be enhanced.
[0012]
Of the annular projections , the first annular projection on the small-diameter cylindrical portion side is formed so as to be inclined toward the small-diameter cylindrical portion. The annular projection is preferably divided as described above, but may be divided into one annular projection without being divided.
[0013]
When the annular projection is divided as described above, a closed space can be formed between the annular protrusions, and the conducted noise can also be reduced in this space, and two closed spaces can be formed together with the closed space on the through hole insertion side, so that the sound insulation performance is improved. Can be enhanced. Also, during the operation of inserting and locking the grommet into the through hole of the vehicle body panel, the bottom surface of the concave portion for locking the vehicle body may be deformed so that the bottom surface of the concave portion enters the space between the first and second annular protrusions. This also makes it possible to reduce the insertion force of the grommet into the through hole. Further, since the first annular projection on the small-diameter cylindrical portion side is inclined, when a pulling force acts on the small-diameter cylindrical portion side, the first annular projection is displaced in a direction perpendicular to the axis, and the locking groove on the outer cylinder side is formed. , And the outer cylinder can be securely held in the folded state.
[0014]
A silencer member is attached to one surface of the vehicle body panel to which the grommet is attached, the surface being opposite to the grommet insertion side, and a skin is attached to the surface of the silencer member. A through hole communicating with the through hole of the vehicle body panel is formed in the silencer member, and a slightly smaller through hole is formed in the skin, and the periphery of the through hole in the skin is the tip of the large-diameter cylindrical portion of the grommet. Is pressed against the outer cylinder surrounding the closed space in a bent state, so that the sound insulation performance can be further improved.
[0015]
Usually, the outer skin is radially slit from the periphery of the through-hole so as to be in close contact with the outer peripheral surface of the grommet, but the grommet in contact with the outer periphery of the through-hole of the skin has a thin outer cylinder and an inner cylinder. Since the closed space is surrounded by the cylinder, the grommet itself has flexibility, and the grommet can be passed through the through-hole of the skin and the skin can be brought into close contact with the outer peripheral surface of the grommet without forming a slit in the skin. As described above, when the skin is not provided with the slit, the sound insulation performance can be further improved.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIGS. 1 to 5 show a first embodiment, in which a grommet 10 is made of rubber or an elastomer, and has a small-diameter tube portion 11 through which a wire harness W / H is inserted in a tightly-fitted state, and a large-diameter tube connected from one end of the small-diameter tube portion 11. The large-diameter cylindrical portion 12 has a double cylindrical structure including an inner cylinder 14 and an outer cylinder 15 as shown in FIG. As shown, the inner cylinder 14 is connected to the small-diameter tube 11, the outer tube 15 is connected to the end of the inner tube 14, and the outer tube 15 is turned back to form the inner tube 14. It has a double cylindrical shape as shown in FIG.
[0017]
The inner cylinder 14 is provided from an outer periphery of a closed wall portion 13 protruding in a radial direction from an outer periphery of one end of the small-diameter cylinder portion 11, and a first annular projection is provided at a position close to a rear end of the inner cylinder 14 on the small-diameter cylinder portion side. The projection 18 and the second annular projection 19 are provided with a V-shaped space 20 therebetween. The first annular projection 18 on the rear end side is inclined rearward with respect to the axis L. The front end face 19a of the second annular projection 19 has the base 19a inclined forward and the projection 19b is oriented perpendicular to the axis. The length from the rear end position of the first annular projection 18 to the front end position of the second annular projection 19 is L1.
[0018]
In the molded state shown in FIG. 2, the thin-walled cylinder portion 21 is extended forward from the front end of the inner cylinder 14, and the front end of the thin-walled cylinder portion 21 is folded back to form the thick vehicle body locking portion 22. Provided. The thin tube portion 21 has a shape shown in FIG. 1 in which a substantially central portion in the length direction is turned back, and a rear portion of the thin tube portion 21 becomes a front thin portion 21a of the inner tube 14 and a thin tube portion. The front side portion 21 becomes the front thin portion 21b of the outer cylinder 15, and a space 24 is formed therebetween. A rib 29 is provided on an inner surface of a continuous portion between the thin tube portion 21 and the inner tube 14.
[0019]
A locking groove 26 is provided in the inner peripheral surface of the vehicle body locking portion 22 which is continuous with the front thin portion 21b of the outer cylinder 15. The locking groove 26 is located at a position corresponding to the first annular projection 18 and the second annular projection 19 in the folded state shown in FIG. 1, and the length in the front-rear direction is L2, and L2 ≦ L1. The first annular projection 18 and the second annular projection 19 are press-fitted into the locking groove 26 to press the distal end surface 18a of the first annular projection 18 against the groove bottom surface 26a of the locking groove 26, and The front end edge 18b of the first annular projection is engaged with the rear end surface 26b of the first projection 26. The distal end surface 19c of the second annular projection 19 is pressed against the groove bottom surface 26a, and the protruding portion 19b is pressed against the front end surface 26c of the locking groove 26. As described above, by pressing the first and second annular projections 18 and 19 into the locking grooves 26, the outer cylinder 15 can be fixed in a folded state outside the inner cylinder 14.
[0020]
As described above, the space 20 between the first annular projection 18 and the second annular projection 19 is sealed by inserting the first annular projection 18 and the second annular projection 19 into the locking groove 26 and pressing them together. At the same time, the space 24 formed by folding the thin portion 21 is also sealed.
[0021]
A concave portion 28 is formed on the outer peripheral surface of the vehicle body locking portion 22 constituting the outer cylinder 15, and a front wall 30 of the concave portion which is a through hole insertion side is inclined toward the other rear wall wall 31 side, and The height of the front side wall 30 is set lower than that of the rear side wall 31 so that the front side wall 30 can fall into the recess 28. The bottom surface 28a of the concave portion 28 is formed in a substantially mountain shape so that both front and rear sides are slightly cut into the side wall side.
[0022]
As described above, the grommet 10 has the vehicle body locking portion 22 provided at a position close to the small-diameter cylindrical portion 11, and the length of the large-diameter cylindrical portion 12 is approximately ／ to して as compared with the conventional grommet. It is as short as possible.
[0023]
As shown in FIG. 3, the grommet 10 having the above-described shape allows the wire harness W / H to penetrate in a state where the small-diameter cylindrical portion 11 is expanded using a jig (not shown), and the large-diameter cylindrical portion 12 is formed. The tape 35 is pulled out from the front end opening, and is fixed by winding a tape 35 around the tip of the small-diameter cylindrical portion 11 and the wire harness W / H. Thereafter, the grommet 10 is filled with a two-liquid sealant, and at this time, the rib 29 acts to prevent the sealant from peeling off. Note that the sealant does not have to be filled.
[0024]
When wiring the wire harness W / H to which the grommet 10 is attached to a vehicle, as shown in FIGS. 4 (A), 4 (B), and 4 (C), the vehicle room (X) passes through the through hole 3 of the vehicle body panel 2 and the vehicle compartment. (Y). A burring 3 a protrudes toward the engine room (X) from the periphery of the through hole 3. A silencer 40 is attached to the indoor side of the vehicle body panel 2, and a through hole 41 having substantially the same diameter as the through hole 3 is formed in the silencer 40. A skin 42 made of a resin sheet or the like is further attached to the surface of the silencer 40, and the skin 42 is provided with a through hole 43 that is slightly smaller than the through hole 41. Conventionally, a slit is provided radially on the periphery of the through hole 43, but the skin 42 on which the grommet 10 of the present invention is mounted is not provided with a slit.
[0025]
The grommet 10 attached to the wire harness W / H is pushed into the through hole 3 of the vehicle body panel from the large-diameter cylindrical portion front end F composed of the thin portions 21a and 21b surrounding the closed space 24 as shown in the drawing. Go. During this insertion, the diameter D1 of the front end F is smaller than the diameter D2 of the through hole 3 of the vehicle body panel 2 and the through hole 41 of the silencer 40, so that the front end F can be easily inserted. Since the diameter D3 of the through hole 43 of the skin 42 of the silencer 40 is set smaller than the front end diameter D1 of the grommet 10, the periphery of the through hole of the skin bends forward to the outer peripheral surface of the thin portion 21b of the outer cylinder of the grommet 10. While sticking. At this time, since the inside of the thin portion 21b is the space 24, the thin portion 21b can also be easily bent. Can be brought into close contact.
[0026]
On the other hand, when the burring 3a projecting from the through hole 3 toward the engine room (X) reaches the inclined front wall 30 of the vehicle body locking portion 22, the burring 3a presses the front wall 30 inward. When the grommet 10 is pushed in, the front wall 30 is pushed down by the burring 3 a and falls into the rear recess 28 as shown in FIG. 4B. At this time, the bottom surface 28 a of the concave portion 28 is deformed so as to cut into the space 20 between the first annular projection 18 and the second annular projection 19, thereby promoting the reduction of the diameter of the front side wall 30. In this manner, the burring 3a can get over the front wall 30 with a low operation force, and the front wall 30 can be passed through the through hole 3 and the burring 3a without requiring a large operation force.
[0027]
When the front side wall 30 comes off from the tip of the burring 3a, the front side wall 30 returns to its original state and projects outward. It is in a state of being fitted in between, and is locked in the concave portion 28. At this time, since the front wall 30 is inclined toward the rear wall 31, the front wall 30 is in close contact with the indoor surface side of the panel 2.
[0028]
As described above, the grommet 10 attached to the wire harness W / H can be locked by passing the grommet 10 through the through hole 3 by one operation of simply pushing the grommet 10 from the engine room side. Therefore, the grommet mounting operation is simplified as compared with the conventional push-pull operation, and the grommet can be mounted without any problem even if there is no space in the vehicle interior and the engine room.
[0029]
Further, since the grommet 10 has the two closed spaces 20 and 24, noise that enters from the engine room side to the room side is attenuated in the spaces 20 and 24, and the sound insulation performance can be improved. Further, since no slit is formed in the periphery of the through hole of the skin 42 of the silencer 40, sound can be prevented from leaking through the slit, and the sound insulation performance can be further improved.
[0030]
With the grommet 10 attached to the vehicle body panel 2, when the wire harness W / H is pulled toward the engine room (X) or when an external force acts in the pulling direction, as shown in FIG. The annular projection 18 is in a direction perpendicular to the axis with respect to the grommet 10. Therefore, since the locking and holding force between the inner cylinder 14 and the outer cylinder 15 is further increased, the waterproof function can be maintained, and the locking groove 26 and the annular projections 18 and 19 can be prevented from being separated from the vehicle body panel 2. The grommet 10 can be reliably prevented from coming off.
[0031]
Further, as shown in FIG. 5B, the grommet 10 may be forced to be bent by about 30 degrees in relation to the other parts on the engine room side and the grommet 10 must be inserted into the through hole 3. In this case, on the upper side of the drawing, the second annular projection 19 abuts and locks on the front end surface 26c of the locking groove 26, and on the lower side, the first annular projection 18 abuts on the rear side surface 26b of the locking groove 26. Locked. Therefore, even if the grommet is inclined, waterproof performance can be ensured, and the annular projections 18 and 19 do not come off from the locking groove 26.
[0032]
FIG. 6 shows a modification of the first embodiment, with the following changes.
{Circle around (1)} The front end surface 26c 'of the locking groove 26 is a tapered surface inclined backward. The tapered surface prevents the locking projection 19 'from moving when pushed.
{Circle around (2)} The front end face 19b 'of the locking projection 19' is continued in a large arc shape without any step. The strength of the locking projections 19 'is maintained by eliminating the dents continuously.
[0033]
7A and 7B show a reference embodiment. In the grommet 10 'of the reference embodiment, the annular projection provided on the inner cylinder 14 is formed from one annular projection 50 without being divided. Further, a lip 51 is provided on the rear side wall 31 of the vehicle body engaging concave portion 28 of the outer cylinder 15 to protrude forward. The tip of the lip 51 protrudes further forward than the front side wall 30 so that the lip 51 is pressed against the surface of the vehicle body panel on the engine room side with the grommet 10 ′ attached to the vehicle body panel 2. The other configuration is the same as that of the first embodiment.
[0034]
【The invention's effect】
As is apparent from the above description, in the grommet according to the present invention, the height of the front side wall of the through hole insertion side of the vehicle body locking recess is reduced and inclined toward the rear side wall. When pressed into the through hole, the front side wall is easily reduced in diameter and passes through the through hole, thereby facilitating the panel mounting operation of the grommet. As described above, since the grommet can be locked in the through hole of the vehicle body panel by only one operation of pushing the grommet, the grommet can be smoothly mounted even when there is no space near the grommet mounting position. Further, since it is only necessary to push the grommet, the workability of mounting the grommet can be improved.
[0035]
In addition, since a closed space surrounded by a thin portion is provided at the end of the through hole insertion side, sound insulation performance can be improved. In particular, if a closed space is provided between the first annular protrusion and the second annular protrusion, two closed spaces can be formed inside the grommet, so that a grommet having excellent sound insulation performance can be obtained.
[0036]
Furthermore, since the large-diameter cylindrical portion is formed by folding back, and the vehicle body locking portion is disposed at a position close to the small-diameter cylindrical portion, the total length of the grommet can be shortened. Therefore, the grommet arrangement space can be reduced. In addition, there are various advantages such as an advantage that waterproof performance can be ensured even when the grommet is attached to the vehicle body panel slightly obliquely.
[Brief description of the drawings]
FIG. 1 is a sectional view of a grommet according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view of the grommet during molding.
FIG. 3 is a sectional view showing a state where a wire harness is attached to the grommet.
FIGS. 4A, 4B, and 4C are views showing a step of locking a grommet attached to the wire harness through a through hole of a vehicle body panel.
5A is a cross-sectional view when the grommet is pulled toward the engine room, and FIG. 5B is a cross-sectional view when the grommet is slightly bent and attached.
FIG. 6 is a cross-sectional view showing a modification of the first embodiment.
7A and 7B show a reference embodiment, wherein FIG. 7A is a cross-sectional view of the grommet of the second embodiment, and FIG.
FIG. 8 is a sectional view showing a conventional grommet.
FIGS. 9A to 9C are views showing a process of inserting and locking a conventional grommet into a through hole of a vehicle body panel.
[Explanation of symbols]
2 Body panel 3 Through-hole 3a Burring 10 Grommet 11 Small-diameter cylindrical part 12 Large-diameter cylindrical part 14 Inner cylinder 15 Outer cylinder 18 First annular projection 19 Second annular projection 20 Sealed space 21 (21a, 21b) Thin part 22 Car body locking Part 24 closed space 26 locking groove 28 concave part 30 inclined front side wall 31 rear side wall 40 silencer 42 skin W / H wire harness

Claims

A grommet that is inserted and locked into a through hole of a vehicle body panel in a state where the grommet is mounted on an automobile wire harness,
A small-diameter cylindrical portion made of a molded product of rubber or elastomer, through which the wire harness is inserted in a tightly fitted state, and a large-diameter cylindrical portion continuous from one end of the small-diameter cylindrical portion, wherein the through-hole is formed from the large-diameter cylindrical portion. To be inserted into
The large-diameter cylindrical portion is folded from the end of the through-hole insertion side to form a double cylindrical shape including an inner cylinder and an outer cylinder,
A first annular projection and a second annular projection are protruded from the outer peripheral surface of the inner cylinder, and the first annular projection and the second annular projection are inserted and locked in locking grooves formed on the inner peripheral surface of the outer cylinder. The inner cylinder and the outer cylinder are held in a folded state, and a V-shaped sealed space is provided between the first annular projection and the second annular projection, and the inner cylinder and the outer cylinder on the through-hole insertion end side. To form two sealed spaces with a closed space,
In addition, a concave portion for locking the vehicle body is formed on the outer peripheral surface of the outer cylinder at a position where the locking groove is formed, and the front side wall of the concave portion on the side where the through hole is inserted is inclined and protruded toward the rear side wall. A grommet characterized in that its protruding height is set low so that it can fall down into a recess.

The thickness of the inner cylinder and the outer cylinder surrounding the closed space at the end of the through hole insertion side is reduced, and the inclined side wall of the vehicle body locking concave portion is continuously provided to the thin portion, while The grommet according to claim 1, wherein the side wall is thick.

Grommet according to claim 1 or claim 2 are formed by inclining the first annular protrusion of the small-diameter cylindrical portion side to the small diameter cylinder portion of the annular projection.

The annular projection is provided so as to protrude from a position close to the small-diameter tube portion side of the outer peripheral surface of the inner cylinder, a concave portion for engaging the vehicle body of the outer tube is provided at a position close to the small-diameter tube portion, and the entire length of the grommet in the axial direction is provided. The grommet according to any one of claims 1 to 3, wherein is set shorter.

The grommet according to any one of claims 1 to 4, which is externally fitted and fixed to the wire harness, is pushed into the through-hole with burring of the vehicle body panel from the side of the large-diameter cylindrical portion to lock the vehicle body. The inclined side wall of the concave portion is passed through the through hole while being tilted into the concave portion by the burring. A grommet installation method that attaches the grommet to the vehicle body panel with only one push-in operation.

A structure in which a grommet is attached to a vehicle body panel by the method according to claim 5,
A silencer member is attached to one surface of the vehicle body panel opposite to the grommet insertion side, and a skin is adhered to the surface of the silencer member, and the silencer member has a through hole communicating with a through hole of the vehicle body panel. Is formed and a slightly smaller through hole is formed in the epidermis,
A grommet panel mounting structure in which a peripheral edge of a through hole of the skin is pressed against an outer cylinder surrounding a sealed space at a tip end of a large-diameter cylindrical portion of the grommet.