JP3843288B2

JP3843288B2 - Pipe fitting

Info

Publication number: JP3843288B2
Application number: JP2002117723A
Authority: JP
Inventors: 智史井上; 秋生保田; 知広中村
Original assignee: Sekisui Chemical Co Ltd; Inoue Sudare Co Ltd; Higashio Mech Co Ltd
Current assignee: Sekisui Chemical Co Ltd; Inoue Sudare Co Ltd; Higashio Mech Co Ltd
Priority date: 2002-04-19
Filing date: 2002-04-19
Publication date: 2006-11-08
Anticipated expiration: 2022-04-19
Also published as: JP2003314763A

Description

【０００１】
【発明の属する技術分野】
本発明は、管継手に関する。
【０００２】
【従来の技術】
合成樹脂材から成る給水・給湯用等のパイプを接続するための管継手は、従来、パイプの端部に挿入される挿入筒部を有する継手本体と、該挿入筒部に外嵌されたパイプの端部を弾発的な締付力で締め付けるためのスリット付きの締付環体と、該締付環体の弾発力に抗して該締付環体を拡径するように上記スリットに離脱可能に挟持されると共に挿入されるパイプの先端部に当接して離脱する拡径片と、上記締付環体を覆うように上記継手本体に螺着される筒状カバー部材と、を備えていた。
【０００３】
【発明が解決しようとする課題】
しかしながら、従来の管継手では、継手本体と締付環体・拡径片とは、筒状カバー部材を介して、一体状に固定されているため、パイプ接続前において、継手本体の向きを回転にて変えなければ、締付環体・拡径片の向きを変えることができず、継手本体の配設位置によっては、拡径片が飛ぶことを目視で確認しながらパイプを接続することができず、パイプの接続不良（未達）が発生する虞れがあった。
【０００４】
また、パイプ接続後において、離脱した拡径片は、自重で、筒状カバー部材内部の下方に位置するため、継手本体の配設位置によっては、離脱した拡径片を上方から目視で確認することができず、パイプ接続確認のチェックを容易に行うことができなかった。
【０００５】
そこで、本発明は、拡径片が飛んだか否かを、外部の如何なる位置からでも、目視で確認でき、パイプ接続不良（未達）を防止することができる管継手を提供することを目的とする。
【０００６】
【課題を解決するための手段】
上述の目的を達成するために、本発明に係る管継手は、被接続用のパイプの端部に挿入される挿入筒部を有する継手本体と、上記挿入筒部に外嵌された上記パイプの端部を弾発的な締付力で締め付けるためのスリット付きの締付環体と、該締付環体の弾発力に抗して該締付環体を拡径するように上記スリットに離脱可能に差し込まれて挟持されると共に挿入される上記パイプの先端部に当接して離脱する拡径片と、該拡径片を挟持している上記締付環体を包囲すると共に上記継手本体に回転自在に外嵌される透明な筒状カバー部材と、を備えているものである。
【０００７】
また、拡径片を挟持している締付環体が、筒状カバー部材の内部に、軸方向位置決め機構を介して、軸心方向への動きを抑制され、筒状カバー部材と共に軸心廻りに回転するように設けられている。また、筒状カバー部材の内周面に、締付環体から離脱した拡径片が該筒状カバー部材と連れ廻って回転するように、複数の小突起部を設けている。また、拡径片が目立つ色彩を有している。
【０００８】
また、締付環体の両側端縁部が、スリット側へ次第に深くなる複数の谷部を連設状に有している。また、締付環体のスリットの両側端部の一方の間隙部にて上記拡径片を挟持するように組付けられると共に、該一方の間隙部の幅寸法が、側端方向へ次第に減少するように形成されている。
【０００９】
また、拡径片は、該拡径片が締付環体に挟圧された状態にて、スリットに保持される挟持部と、締付環体の軸心方向外方へ突設されると共に締付環体の側端縁部に当接して挟持位置を規制する規制部と、締付環体の内径方向へ突設されて締付環体の内周面に接触すると共に挿入されるパイプの先端部に当接する押圧部と、を有している。
【００１０】
また、挟持部の両側縁部が、規制部に連設される盗み部と、該盗み部に連設される頂部を有し、該頂部が、締付環体のスリットを形成する両端縁部に点又は線状に接触している。また、押圧部は、その内径方向端部が挿入されるパイプ側へ折り曲げられている折曲部を有している。
【００１１】
また、拡径片が、縦断面に於て、規制部が締付環体の側端縁部に接触する部分となると共に拡径片の揺動中心となる支点と、パイプが最初に押圧部に接触する部分となる力点と、挟持部と締付環体とが接触する作用点と、を有し、支点と力点との距離が、支点と作用点との距離の３倍〜10倍に設定されている。
【００１２】
【発明の実施の形態】
以下、実施の形態を示す図面に基づき、本発明を詳説する。
【００１３】
図１に、本発明に係る管継手の実施の一形態であってパイプの未接続状態の縦断面図を示し、図２に、パイプを接続した状態の縦断面図を示し、本管継手Ｊは、被接続用のパイプ１の端部に挿入される継手本体２と、継手本体２に外嵌されたパイプ１の端部を締め付けるためのスリット30付きの締付環体３と、締付環体３のスリット30に離脱可能に挟持されると共に挿入されるパイプ１の先端部に当接して離脱する拡径片４と、締付環体３を包囲すると共に継手本体２に回転自在に外嵌される透明な筒状カバー部材５と、を備えている。
【００１４】
パイプ１は、給水、給湯用等に用いられ、例えば、架橋ポリエチレン又はポリブテン等の合成樹脂材から成る。
【００１５】
継手本体２は、金属製であり、その一端側に、パイプ１の端部に挿入される挿入筒部20を有し、挿入筒部20の外周面には、パイプ１を抜け止め状態に掛止するための複数の環状抜止突条部が同心円状に並設されると共に、（Ｏリング等の）シール部材21が装着される環状嵌込溝22…が設けられている。また、継手本体２の他端側には、例えば、（図示省略の）接続対象となる部材に、螺合する雄ネジ23が形成されている。
【００１６】
締付環体３は、炭素鋼やバネ鋼等から成り、軸心方向のスリット（切割部）30を有し、挿入筒部20に外嵌されたパイプ１の端部をパイプ接続状態で弾発的な締付力で締め付ける。
【００１７】
拡径片４は、炭素鋼等の高剛性な鋼材からなり、図１に示す初期状態（パイプ未接続状態）にて、締付環体３の弾発力に抗して、締付環体３のスリット30に離脱可能に挟圧され、締付環体３を、パイプ１の挿入が可能な程度に拡径している。さらに、拡径片４は、図１から図２のように、挿入されるパイプ１により、挟持されているスリット30から軸心方向外方へ押し出されて、離脱し、締付環体３の縮径を可能とし、締付環体３の弾発付勢力にて、パイプ１を締め付ける。
【００１８】
筒状カバー部材５は、透明樹脂材からなり、例えば、線膨張係数が（金属に近い程に）小さく、強度、耐熱性、耐薬品性に優れたポリサルフォン（ＰＳＦ）の材質からなる。
【００１９】
筒状カバー部材５は、拡径部５ａと縮径部５ｂとから成り、縮径部５ｂの内周面６に設けられた突条部８が、挿入筒部20の基端部（他端部）に設けられた凹周溝24に抜け止め状に嵌め込まれ、筒状カバー部材５が継手本体２に回転自在となる。そして、拡径部５ａの内周面６と、挿入筒部20の外周面と、の間には、拡径状態の締付環体３とパイプ１との挿入を可能にする程度の間隙部が設けられている。なお、縮径部５ｂに凹周溝を設け、挿入筒部20に突条部を設けてもよい。
【００２０】
拡径部５ａの開口側には、内鍔部９ａを有する抜止カバー９が外嵌状に取り付けられている。即ち、拡径部５ａの外周面に設けられた凹周溝10に、抜止カバー９の内周面に設けられた突条部11が、抜け止め状に嵌め込まれている。また、金属製の抜止カバー９は、筒状カバー部材５に（冷間）圧入されており、抜止カバー９は、筒状カバー部材５に対して空転しない。なお、抜止カバー９を筒状カバー部材５に螺着するようにしてもよい。
【００２１】
この抜止カバー９により、本管継手Ｊに接続されたパイプ１に、引抜力が掛かっても、締付環体３等が、抜止カバー９の内鍔部９ａに当接して動きを抑制される。また、抜止カバー９を掴持して回動させても、筒状カバー部材５を共に回動させることができる。即ち、筒状カバー部材５と継手本体２との回転摩擦抵抗力よりも、抜止カバー９の筒状カバー部材５への圧接力が大きい。
【００２２】
そして、本管継手Ｊの組立は、筒状カバー部材５の内部に、拡径片４にて拡径された締付環体３等を装着した後に、抜止カバー９を筒状カバー部材５に圧着してから、筒状カバー部材５を継手本体２に取り付ける。
【００２３】
拡径片４を挟持している締付環体３は、筒状カバー部材５の内部に、軸方向位置決め機構Ｋを介して、軸心方向への動きを抑制され、筒状カバー部材５と共に軸心廻りに回転するように設けられている。
【００２４】
具体的に述べると、拡径した締付環体３は、筒状カバー部材５の内周面６に突設された複数の小突起部７…と、抜止カバー９の内鍔部９ａと、の間に配設されると共に、締付環体３と内鍔部９ａとの間に配設された（発泡ポリエチレン等からなる）弾性スペーサ12、及び、（金属製の）バネリング13によって、弾発的に位置決めされている。即ち、軸方向位置決め機構Ｋは、小突起部７…、弾性スペーサ12、バネリング13、内鍔部９ａから構成される。
【００２５】
従って、この軸方向位置決め機構Ｋにより、締付環体３が筒状カバー部材５と連れ廻って回転することができる。要するに、パイプ１を接続する前に、筒状カバー部材５を回転させて、拡径片４を見やすい位置に向けることができ、パイプ１を挿入しつつ、拡径片４が飛ぶのを目視で確認でき、確実にパイプ１を接続することができる。
【００２６】
小突起部７は、図１〜図３に示すように、拡径部５ａの内周面６に周方向に等間隔に、複数個（本実施の形態では５個）設けられており、締付環体３から離脱した拡径片４が筒状カバー部材５と連れ廻って回転するように構成されている。即ち、離脱した拡径片４は、筒状カバー部材５の内周面６と、継手本体２の外周面と、隣り合う２つの小突起部７，７と、縮径している締付環体３と、締め付けられているパイプ１と、から形成される所定の共連れ用空間14に、常時、配置される。
【００２７】
従って、この共連れ用空間14により、図３（イ）に示すように、継手本体２が床面Ｆの直近にある場合で、離脱した拡径片４が、筒状カバー部材５の内部の下方位置にあって（即ち、下方の共連れ用空間14内にあって）、外部から目視できないときは、筒状カバー部材５を矢印方向に回転させることで、小突起部７，７にて、拡径片４をかきあげ、図３（ロ）に示すように、拡径片４を上方位置に持ってくることができ、外部から拡径片４を容易に目視できる。
【００２８】
また、図４（イ）に示すように、継手本体２がコーナー部（角部）Ｃに近接している場合で、離脱した拡径片４が、筒状カバー部材５の内部のコーナー部Ｃ側にあって、外部から目視できないときは、筒状カバー部材５を矢印方向に回転させることで、小突起部７，７にて、拡径片４をかきあげ、図４（ロ）に示すように、拡径片４をコーナー部Ｃと反対側に持ってくることができ、外部から拡径片４を容易に目視できる。
【００２９】
要するに、図３と図４に示すように、パイプ１を接続した後に、筒状カバー部材５を回転させて、離脱した拡径片４を見やすい位置に向けることができ、拡径片４が飛んでいることを目視で確認でき、パイプ１が確実に接続しているのをチェックすることができる。一方、筒状カバー部材５を回転させても、離脱した拡径片４を発見することができないときは、拡径片４が飛んでおらず、パイプ１が確実に接続していないことが判る。
【００３０】
なお、拡径片４が目立つ色彩を有するようにすれば、拡径片４の発見が容易となり、パイプ１の接続のチェックを円滑に行うことができる。なお、目立つ色彩とは、拡径片４以外の他の部材の色彩と比較して、使用者にとって際立って目をひく（赤色、黄色等の）色彩をいう。
【００３１】
ここで、締付環体３は、自由状態（縮径状態）を表す図５と図６、及び、拡径状態を表す図11と図12に示すように、その両側端縁部31，31が、スリット30側へ次第に深くなる複数の谷部32…を連設状に有している。要するに、左右の谷部32，32の底部における締付環体３の左右幅寸法を、スリット30側へ小さくなるようにすることで、締付環体３の拡径のときに、締付環体３のスリット30側も十分に弾性変形させることができ、（自由状態真円状の）締付環体３を真円状に拡径することができる。なお、谷部32…以外の部位における締付環体３の幅寸法は、一定に設定されている。
【００３２】
従って、拡径している締付環体３を真円状とすることで、その締付環体３内にパイプ１を挿入する際に、パイプ１が締付環体３に接触することなく、パイプ１を円滑に挿入することができる。
【００３３】
なお、締付環体３の側端縁部31，31における谷部32…の形成位置は、（図１に示すように、）パイプ１を締付環体３内へ挿入していくときに、側端縁部31の谷部32…以外の部位で、締付環体３が全ての小突起部７…に接触するように、設定されている。従って、パイプ１の挿入時（即ち、パイプ１が拡径片４を押圧したとき）における締付環体３の姿勢を、継手本体２の軸心と同心状となるように保持することができ、パイプ１により拡径片４を確実に離脱させることができる。
【００３４】
スリット30は、一方の端縁部34に形成された突部35が、他方の端縁部34に形成された凹部36に嵌合するように、凹凸嵌合状に形成されている。スリット30をこのような形状にすることにより、パイプ１に対する締付力を周方向に途切れることなく連続的に作用させることができ、パイプ１を閉ループ状に万遍なく押圧することができ、軸心方向の流体漏れを防止してシール性が向上する。
【００３５】
スリット30の両側端部の一方の間隙部30ａにて拡径片４を挟持するように組付けられ、その一方の間隙部30ａの幅寸法が、側端方向へ次第に減少するように形成されている。即ち、図７に示すように、間隙部30ａを形成する端縁部34，34の成す角度θが、1.5 °〜６°（好ましくは、２°〜４°）に設定されており、間隙部30ａにて挟持する拡径片４を、締付環体３の中央側（突部35側）へ、引き寄せることができる。
【００３６】
拡径片４は、図８と図９に示すように、平面視略山形状の規制部41と、規制部41に連設されて側面視Ｌ字状に折り曲げられた挟持部40と、挟持部40に連設されて背面視略円弧状の押圧部42と、からなり、図10に示すように、プレス加工にて形成された平板状の中間製品を、挟持部40の部位にて側面視Ｌ字状に折り曲げることで成形される。
【００３７】
挟持部40の両側縁部43，43は、夫々、規制部41に連設される盗み部44と、盗み部44に連設される頂部45と、頂部45に連設されるテーパ部47と、テーパ部47と押圧部42との間に配設される盗み部48と、を有している。このテーパ部47は、挟持部40の幅寸法が、規制部41から押圧部42へ次第に縮小するように形成されている。
【００３８】
規制部41は、挟持部40の左右幅よりも、左右へ突出した顎部（耳部）41ａ，41ａを有している。押圧部42は、その先端縁部の左右両端部が、平面視、規制部41と反対方向へ、折り曲げられている折曲部46，46を有し、さらに、押圧部42は、挟持部40の左右幅よりも、左右へ突出した膝部42ａ，42ａを有している。
【００３９】
図11〜図14に、拡径片４が締付環体３に挟圧された状態を示し、挟持部40は、スリット30に保持され、規制部41は、締付環体３の軸心方向外方へ突設されると共に締付環体３の側端縁部31に当接して挟持位置を規制し、押圧部42は、締付環体３の内径方向へ突設されて締付環体３の内周面33に接触すると共に挿入されるパイプ１の先端部に当接する。また、挟持部40の両側縁部43，43の頂部45，45が、締付環体３のスリット30を形成する両端縁部34，34に点又は線状に接触している。
【００４０】
このとき、図13に示すように、拡径片４は、（図７にて既述したように）幅寸法が減少しているスリット30の間隙部30ａにより、スリット30内部側へ引き込まれるが、規制部41の顎部41ａ，41ａにより、締付環体３の側端縁部31に引っ掛かっている。
【００４１】
また、図14に示すように、締付環体３の端縁部34，34の相互間隔寸法は、横断面、外径側へ次第に増大するように形成されているため、拡径片４は、締付環体３の外径側へ押し出されるが、押圧部42の膝部42ａ，42ａにより、締付環体３の内周面33に引っ掛かっている。
【００４２】
従って、拡径片４に掛かる軸心方向内方への引張力、及び、外径方向への押出力により、拡径片４の姿勢を保持することができる。要するに、作業中における締付環体３の落下等で拡径片４が容易に外れることがない。なお、挟持部40の盗み部44，48により、締付環体３の端縁部34，34の側端縁部及び内径側縁部が、拡径片４に接触するのを防止し、拡径片４を確実に保持することができる。
【００４３】
また、図14に示すように、円弧状の押圧部42は、継手本体２の挿入筒部20に、接近した状態で沿って配設されるため、パイプ１の先端面への接触面積が大きくなり、パイプ１が拡径片４を確実に押圧することができる。
【００４４】
次に、本管継手Ｊによるパイプ１の接続の作用（機能）を説明する。即ち、図１に示すように、パイプ１を本管継手Ｊに挿入していくと、図15（イ）に示すように、パイプ１の先端が、拡径片４の押圧部42の折曲部46に力点Ｐにて接触して、拡径片４を押圧し、拡径片４が、支点Ｓを中心として揺動（回動）しながら、挟持部40と締付環体３（端縁部34）とが接触する作用点Ｎが、締付環体３から抜け出るように移動する。なお、力点Ｐとは、パイプ１が最初に押圧部42に接触する部分をいい、支点Ｓとは、規制部41（顎部41ａ）が締付環体３の側端縁部31に接触する（引っ掛かる）部分をいい、作用点Ｎとは、挟持部40が締付環体３に特に強く保持されている部分をいう。
【００４５】
このとき、支点Ｓと力点Ｐとの距離Ｒが、支点Ｓと作用点Ｎとの距離ｒに比べて十分に長いため、テコの原理にて、パイプ１の小さな押圧力で、締付環体３に強力な締付力で締め付けられている拡径片４を、容易に動かすことができる。即ち、押圧部42の内径方向端部に、挿入されるパイプ１側へ折り曲げられている折曲部46を設けているため、拡径片４が回転し始めるまでの初動に必要な力を一番遠い部分で働かせることができる。
【００４６】
また、支点Ｓと力点Ｐとの距離Ｒは、支点Ｓと作用点Ｎとの距離ｒの３倍〜10倍に設定するのが好ましく、拡径片４を適度の大きさに形成でき、パイプ１の押圧力を小さくできる。即ち、距離Ｒを距離ｒの３倍未満に設定すると、パイプ１の押圧力を大きくする必要があり、プラスチック製のパイプ１の先端面が変形するだけで拡径片４が離脱しない虞れがあり、他方、距離Ｒを距離ｒの10倍を越えて設定すると、拡径片４が必要以上に大きくなり、筒状カバー部材５が無駄に大きくなる。
【００４７】
そして、拡径片４が回転していくと、図15（ロ）に示すように、パイプ１の先端が、（当初）力点Ｐから最終力点Ｑへ変移して、最終力点Ｑにて拡径片４を押圧していき、図15（ハ）に示すように、拡径片４を締付環体３から離脱させ、図２に示すように、パイプ１を締付環体３にて締め付けて、パイプ１を継手本体２に接続することができる。なお、図15（ロ）に示す支点Ｓと最終力点Ｑとの距離Ｔが、図15（イ）に示す支点Ｓと力点Ｐとの距離Ｒに比べて小さくなり、回転モーメントが小さくなっているが、一般に、動摩擦係数は静止摩擦係数よりも小さいため、拡径片４が一旦動き始めると、後は、小さな力で拡径片４を十分に動かすことができるので問題はない。
【００４８】
上述のように構成された締付環体３及び拡径片４によれば、落下などの衝撃では拡径片４が締付環体３から容易に離脱しないが、パイプ１の挿入による小さな押圧力で拡径片４を締付環体３から容易に離脱させるようにすることができる。即ち、相反する要望を同時に満たすことができる。
【００４９】
なお、本発明は上述の実施の形態に限定されず、例えば、締付環体３及び拡径片４の形状等は、本実施の形態に限らず、種々設計変更可能である。
【００５０】
【発明の効果】
本発明は上述の如く構成されるので、次に記載する効果を奏する。
【００５１】
（請求項１によれば、）透明な筒状カバー部材５を回転させることで、拡径片４を見やすい位置に向けることができ、外部の如何なる位置からでも、拡径片４が飛んでいるか否かを目視で間違いなくチェックでき、パイプ接続不良を防止することができる。
【００５２】
（請求項２によれば、）パイプ挿入接続前において、筒状カバー部材５を、予め、軸心廻りに回転させて、拡径片４を所望の見やすい位置に配置することができ、拡径片４が飛ぶことを目視で確認しながら、パイプ１を挿入することができ、パイプ１の接続不良を防止することができる。
（請求項３によれば、）パイプ挿入接続後において、筒状カバー部材５を、軸心廻りに回転させて、拡径片４が飛んでいるか否かを目視で確認することができ、パイプ１の接続不良を防止することができる。要するに、パイプ接続施工後のチェックが容易となる。
（請求項４によれば、）パイプ接続前、及び、パイプ接続後において、拡径片４を見つけやすくなり、パイプ接続不良を一層確実に防止することができる。
【００５３】
（請求項５によれば、）締付環体３を真円状に拡径することができるため、拡径している締付環体３内に、パイプ１を円滑に挿入することができ、パイプ接続作業を容易に行うことができる。
（請求項６によれば、）締付環体３の締付力により、拡径片４を締付環体３側へ引き寄せることができ、拡径片４を締付環体３に確実に組付けることができると共に、拡径片４の組付姿勢を保持することができる。
【００５４】
（請求項７によれば、）拡径片４は、規制部41により、締付環体３の軸心方向の挟持姿勢を保持されると共に、押圧部42により、締付環体３の径方向の挟持姿勢を保持され、作業中の落下等の衝撃に対しても、拡径片４は締付環体３から容易に外れることがなく、パイプ１接続前に、拡径片４が不意に離脱することを防止することができる。
【００５５】
（請求項８によれば、）拡径片４の締付環体３による挟持姿勢を一層安定させることができると共に、パイプ１の押圧による拡径片４の離脱を容易にすることができる。即ち、作業中の落下等の衝撃に対しての拡径片４の離脱を防止すると共に、パイプ１の接続作業が良好なものとなる。
（請求項９によれば、）回転モーメントを大きくすることができるため、軽い力でパイプ１を挿入しても、確実に、拡径片４を離脱することができる。また、パイプ１を早めに拡径片４に当接させることができる。
【００５６】
（請求項10によれば、）拡径片４等の部材を大きくすることなく、回転モーメントを大きくすることができるため、管継手のコンパクト化を図ることができると共に、プラスチック製の（軟らかい）パイプ１の先端をもって拡径片４を飛び出させる（離脱させる）ことが可能となって、パイプ１の接続作業を確実かつ迅速に行い得る。
【図面の簡単な説明】
【図１】本発明の実施の一形態を示す縦断面図である。
【図２】パイプを挿入した状態を示す縦断面図である。
【図３】作用説明を兼ねた横断面図である。
【図４】作用説明を兼ねた横断面図である。
【図５】締付環体の側面図である。
【図６】図５のＡ−Ａ断面図である。
【図７】締付環体の要部拡大図である。
【図８】拡径片の平面図である。
【図９】拡径片の背面図である。
【図１０】拡径片の展開図である。
【図１１】拡径片を挟圧した状態の締付環体の側面図である。
【図１２】図11のＢ−Ｂ断面図である。
【図１３】締付環体に挟持されている拡径片の作用説明図である。
【図１４】締付環体に挟持されている拡径片の作用説明図である。
【図１５】拡径片の離脱状態を示す作用説明図である。
【符号の説明】
１パイプ
２継手本体
３締付環体
４拡径片
５筒状カバー部材
６内周面
７小突起部
20 挿入筒部
30 スリット
30ａ間隙部
31 側端縁部
32 谷部
33 内周面
34 端縁部
40 挟持部
41 規制部
42 押圧部
43 側縁部
44 盗み部
45 頂部
46 折曲部
Ｋ軸方向位置決め機構
Ｓ支点
Ｐ力点
Ｎ作用点
Ｒ距離
ｒ距離[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pipe joint.
[0002]
[Prior art]
A pipe joint for connecting pipes for water supply and hot water supply made of a synthetic resin material has conventionally been a joint body having an insertion cylinder part inserted into an end part of the pipe, and a pipe externally fitted to the insertion cylinder part A tightening ring with a slit for tightening the end of the ring with a resilient tightening force, and the slit so as to expand the diameter of the tightening ring against the resilient force of the tightening ring A diameter-enlarging piece that is releasably sandwiched and abutted against the tip of the inserted pipe, and a cylindrical cover member that is screwed to the joint body so as to cover the fastening ring. I was prepared.
[0003]
[Problems to be solved by the invention]
However, in the conventional pipe joint, the joint body and the tightening ring / expanded diameter piece are integrally fixed via the cylindrical cover member, so the direction of the joint body is rotated before connecting the pipe. The direction of the tightening ring / expanded piece cannot be changed unless it is changed in, and depending on the position of the joint body, the pipe can be connected while visually confirming that the expanded piece is flying. There was a risk that a pipe connection failure (not reached) could occur.
[0004]
Further, after the pipe is connected, the detached diameter-expanding piece is located under the inside weight of the cylindrical cover member by its own weight, so that depending on the position of the joint body, the detached diameter-expanding piece is visually confirmed from above. It was not possible to check the pipe connection easily.
[0005]
Accordingly, an object of the present invention is to provide a pipe joint that can visually check whether or not the diameter-expanded piece has been blown from any external position, and can prevent poor pipe connection (not achieved). To do.
[0006]
[Means for Solving the Problems]
In order to achieve the above-described object, a pipe joint according to the present invention includes a joint main body having an insertion cylinder portion inserted into an end portion of a pipe to be connected, and the pipe externally fitted to the insertion cylinder portion. A tightening ring with a slit for tightening the end with a resilient tightening force, and a slit in the slit so as to expand the diameter of the tightening ring against the elastic force of the tightening ring. A diameter-enlarging piece that is releasably inserted and clamped and inserted and abuts on the tip of the pipe, and surrounds the tightening ring that clamps the diameter-expanding piece, and the joint body And a transparent cylindrical cover member that is rotatably fitted to the housing.
[0007]
Further, the fastening ring holding the diameter-expanding piece is restrained from moving in the axial direction through the axial positioning mechanism inside the cylindrical cover member, and rotates around the axial center together with the cylindrical cover member. It is provided to rotate. In addition, a plurality of small protrusions are provided on the inner peripheral surface of the cylindrical cover member so that the diameter-expanded piece detached from the fastening ring rotates along with the cylindrical cover member. Moreover, the diameter-expanded piece has a conspicuous color.
[0008]
Further, both side edge portions of the tightening ring have a plurality of valley portions that are gradually deepened toward the slit side in a continuous manner. Further, it is assembled so that the above-mentioned diameter-expanding piece is sandwiched by one gap portion at both end portions of the slit of the tightening ring, and the width dimension of the one gap portion gradually decreases in the side end direction. It is formed as follows.
[0009]
Further, the diameter-expanding piece projects in the axial direction of the clamping ring and the clamping part held by the slit in a state in which the diameter-enlarging piece is clamped by the clamping ring. A restricting portion that abuts the side edge of the tightening ring and restricts the clamping position, and a pipe that protrudes in the inner diameter direction of the tightening ring and contacts the inner peripheral surface of the tightening ring and is inserted And a pressing portion that abuts on the front end portion.
[0010]
Further, both side edges of the clamping part have a stealing part connected to the restricting part and a top part connected to the stealing part, and the top parts form both end edges that form slits of the tightening ring. In contact with dots or lines. Moreover, the press part has the bending part currently bent to the pipe side in which the inner diameter direction edge part is inserted.
[0011]
Further, in the longitudinal section, the diameter-expanding piece becomes a portion where the restricting portion comes into contact with the side edge of the tightening ring and the fulcrum that becomes the swing center of the diameter-expanding piece, and the pipe is the pressing portion first. And a point of action where the clamping part and the tightening ring contact each other, and the distance between the fulcrum and the point of force is 3 to 10 times the distance between the fulcrum and the point of action. Is set.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments.
[0013]
FIG. 1 is a longitudinal sectional view of a pipe joint according to an embodiment of the present invention in a pipe unconnected state, and FIG. 2 is a longitudinal sectional view of a pipe connected state. Includes a joint body 2 inserted into the end of the pipe 1 to be connected, a tightening ring 3 with a slit 30 for tightening the end of the pipe 1 fitted on the joint body 2, and a tightening A diameter-enlarging piece 4 that is detachably held in the slit 30 of the ring body 3 and abuts on the tip of the inserted pipe 1 and surrounds the tightening ring body 3 and is rotatable to the joint body 2. And a transparent tubular cover member 5 to be externally fitted.
[0014]
The pipe 1 is used for water supply, hot water supply, etc., and is made of, for example, a synthetic resin material such as crosslinked polyethylene or polybutene.
[0015]
The joint body 2 is made of metal, and has an insertion tube portion 20 inserted into the end portion of the pipe 1 on one end side thereof. The pipe 1 is hooked on the outer peripheral surface of the insertion tube portion 20. A plurality of annular retaining protrusions for stopping are arranged concentrically in parallel, and annular fitting grooves 22 in which a seal member 21 (such as an O-ring) is mounted are provided. Further, on the other end side of the joint body 2, for example, a male screw 23 that is screwed into a member to be connected (not shown) is formed.
[0016]
The tightening ring 3 is made of carbon steel, spring steel or the like, has a slit (cut portion) 30 in the axial direction, and elastically connects the end portion of the pipe 1 fitted to the insertion tube portion 20 in a pipe connection state. Tighten with spontaneous tightening force.
[0017]
The diameter-expanding piece 4 is made of a highly rigid steel material such as carbon steel, and is fastened against the elastic force of the fastening ring 3 in the initial state shown in FIG. The clamping ring 3 is squeezed by the three slits 30 so as to be detachable, and the diameter of the fastening ring 3 is expanded to the extent that the pipe 1 can be inserted. Further, as shown in FIGS. 1 to 2, the diameter-enlarging piece 4 is pushed out from the slit 30 sandwiched by the inserted pipe 1 outwardly in the axial direction, detached, and attached to the fastening ring 3. The pipe 1 is tightened by the elastic urging force of the tightening ring 3 that allows the diameter to be reduced.
[0018]
The cylindrical cover member 5 is made of a transparent resin material, and is made of, for example, a polysulfone (PSF) material having a small linear expansion coefficient (as it is closer to a metal) and excellent in strength, heat resistance, and chemical resistance.
[0019]
The cylindrical cover member 5 includes an enlarged diameter portion 5a and a reduced diameter portion 5b, and the protrusion 8 provided on the inner peripheral surface 6 of the reduced diameter portion 5b is connected to the proximal end portion (the other end of the insertion cylinder portion 20). The cylindrical cover member 5 is rotatably fitted to the joint body 2 by being fitted in a concave circumferential groove 24 provided in the portion). Between the inner peripheral surface 6 of the enlarged diameter portion 5a and the outer peripheral surface of the insertion cylinder portion 20, there is a gap portion that allows insertion of the tightened ring 3 and the pipe 1 in an enlarged state. Is provided. In addition, a concave circumferential groove may be provided in the reduced diameter portion 5b, and a protrusion may be provided in the insertion tube portion 20.
[0020]
On the opening side of the enlarged diameter portion 5a, a retaining cover 9 having an inner flange portion 9a is attached in an outer fitting shape. That is, the ridge 11 provided on the inner peripheral surface of the retaining cover 9 is fitted in the concave peripheral groove 10 provided on the outer peripheral surface of the enlarged diameter portion 5a in a retaining shape. Further, the metal retaining cover 9 is press-fitted into the cylindrical cover member 5 (cold), and the retaining cover 9 does not idle with respect to the cylindrical cover member 5. The retaining cover 9 may be screwed onto the cylindrical cover member 5.
[0021]
Even if a pulling force is applied to the pipe 1 connected to the main pipe joint J, the retaining ring 9 abuts against the inner flange portion 9a of the retaining cover 9 so that the movement is suppressed. . Even if the retaining cover 9 is gripped and rotated, the cylindrical cover member 5 can be rotated together. That is, the pressure contact force of the retaining cover 9 to the cylindrical cover member 5 is greater than the rotational frictional resistance force between the cylindrical cover member 5 and the joint body 2.
[0022]
And the assembly of the main pipe joint J is carried out by attaching the retaining cover 9 to the cylindrical cover member 5 after mounting the fastening ring 3 and the like expanded in diameter by the expanded diameter piece 4 inside the cylindrical cover member 5. After crimping, the cylindrical cover member 5 is attached to the joint body 2.
[0023]
The tightening ring 3 holding the diameter-enlarging piece 4 is restrained from moving in the axial direction inside the cylindrical cover member 5 via the axial positioning mechanism K, together with the cylindrical cover member 5. It is provided to rotate around the axis.
[0024]
Specifically, the tightened ring 3 having an enlarged diameter includes a plurality of small protrusions 7 projecting from the inner peripheral surface 6 of the cylindrical cover member 5, an inner flange portion 9 a of the retaining cover 9, The elastic spacer 12 (made of foamed polyethylene or the like) and the spring ring 13 (made of metal) disposed between the tightening ring 3 and the inner flange portion 9a It is positioned spontaneously. That is, the axial positioning mechanism K is composed of small protrusions 7, elastic spacers 12, spring rings 13, and inner flanges 9 a.
[0025]
Therefore, the tightening ring 3 can be rotated together with the cylindrical cover member 5 by the axial positioning mechanism K. In short, before connecting the pipe 1, the cylindrical cover member 5 can be rotated to direct the enlarged diameter piece 4 to an easily viewable position, and the enlarged diameter piece 4 can be visually observed while the pipe 1 is inserted. The pipe 1 can be reliably connected.
[0026]
As shown in FIGS. 1 to 3, a plurality of small protrusions 7 (five in this embodiment) are provided on the inner peripheral surface 6 of the enlarged diameter portion 5a at equal intervals in the circumferential direction. The enlarged diameter piece 4 detached from the ring body 3 is configured to rotate with the cylindrical cover member 5. That is, the detached diameter-expanding piece 4 includes an inner peripheral surface 6 of the cylindrical cover member 5, an outer peripheral surface of the joint body 2, two adjacent small projections 7 and 7, and a tightening ring having a reduced diameter. It is always arranged in a predetermined shared space 14 formed by the body 3 and the pipe 1 that is tightened.
[0027]
Therefore, by this shared space 14, as shown in FIG. 3 (a), when the joint main body 2 is in the immediate vicinity of the floor surface F, the separated diameter-expanding piece 4 can be removed from the inside of the cylindrical cover member 5. When it is in the lower position (that is, in the lower shared space 14) and cannot be seen from the outside, the cylindrical cover member 5 is rotated in the direction of the arrow so that the small protrusions 7 and 7 The diameter-expanding piece 4 can be scraped up, and the diameter-expanding piece 4 can be brought to an upper position as shown in FIG.
[0028]
Further, as shown in FIG. 4A, when the joint body 2 is close to the corner portion (corner portion) C, the detached diameter-expanding piece 4 is the corner portion C inside the cylindrical cover member 5. When it is on the side and cannot be seen from the outside, the cylindrical cover member 5 is rotated in the direction of the arrow to scoop up the enlarged diameter piece 4 with the small protrusions 7 and 7 as shown in FIG. Moreover, the diameter-expanding piece 4 can be brought to the opposite side to the corner part C, and the diameter-expanding piece 4 can be easily visually confirmed from the outside.
[0029]
In short, as shown in FIGS. 3 and 4, after connecting the pipe 1, the cylindrical cover member 5 can be rotated so that the detached enlarged diameter piece 4 can be directed to an easy-to-see position, and the enlarged diameter piece 4 flies. It can be confirmed visually that the pipe 1 is securely connected. On the other hand, when the detached diameter-expanding piece 4 cannot be found even when the cylindrical cover member 5 is rotated, it is understood that the diameter-expanding piece 4 is not flying and the pipe 1 is not securely connected. .
[0030]
If the enlarged diameter piece 4 has a conspicuous color, discovery of the enlarged diameter piece 4 is facilitated, and the connection of the pipe 1 can be checked smoothly. Note that the conspicuous color refers to a color (red, yellow, etc.) that is conspicuously noticeable for the user as compared with the color of other members other than the diameter-expanded piece 4.
[0031]
Here, as shown in FIGS. 5 and 6 representing the free state (diameter-reduced state) and FIGS. 11 and 12 representing the diameter-enlarged state, the tightening ring 3 has both side edge portions 31 and 31 thereof. However, it has a plurality of valleys 32 that are gradually deepened toward the slit 30 in a continuous manner. In short, when the diameter of the tightening ring 3 is increased, the tightening ring 3 is reduced by reducing the left and right width dimensions of the tightening ring 3 at the bottom of the left and right troughs 32 and 32 to the slit 30 side. The slit 30 side of the body 3 can also be sufficiently elastically deformed, and the diameter of the fastening ring body 3 (in a free state of a perfect circle) can be expanded to a perfect circle. It should be noted that the width dimension of the tightening ring 3 other than the valleys 32 is set to be constant.
[0032]
Therefore, by making the tightening ring 3 whose diameter is enlarged into a perfect circle, the pipe 1 does not come into contact with the tightening ring 3 when the pipe 1 is inserted into the tightening ring 3. The pipe 1 can be inserted smoothly.
[0033]
It should be noted that the formation positions of the valley portions 32... At the side edge portions 31, 31 of the tightening ring 3 are determined when the pipe 1 is inserted into the tightening ring 3 (as shown in FIG. 1). The tightening ring 3 is set so as to come into contact with all the small protrusions 7 at a part other than the valleys 32 of the side edge 31. Accordingly, the posture of the tightening ring 3 when the pipe 1 is inserted (that is, when the pipe 1 presses the diameter-expanding piece 4) can be held so as to be concentric with the axis of the joint body 2. The diameter-expanding piece 4 can be reliably detached by the pipe 1.
[0034]
The slit 30 is formed in a concavo-convex shape so that a protrusion 35 formed on one end edge 34 is engaged with a recess 36 formed on the other end edge 34. By making the slit 30 in such a shape, the tightening force on the pipe 1 can be continuously applied without being interrupted in the circumferential direction, and the pipe 1 can be uniformly pressed in a closed loop shape. Sealing performance is improved by preventing fluid leakage in the central direction.
[0035]
The slit 30 is assembled so that the enlarged diameter piece 4 is sandwiched by one gap portion 30a at both end portions of the slit 30, and the width dimension of the one gap portion 30a is formed so as to gradually decrease in the side end direction. Yes. That is, as shown in FIG. 7, the angle θ formed between the edge portions 34 and 34 forming the gap 30a is set to 1.5 ° to 6 ° (preferably 2 ° to 4 °). The diameter-enlarging piece 4 clamped by 30a can be drawn toward the center side (projection 35 side) of the tightening ring 3.
[0036]
As shown in FIGS. 8 and 9, the diameter-expanding piece 4 includes a restriction portion 41 having a substantially mountain shape in plan view, a holding portion 40 that is connected to the restriction portion 41 and is bent in an L shape in side view, A pressing portion 42 that is connected to the portion 40 and has a substantially circular arc shape when viewed from the back side, and as shown in FIG. It is molded by bending it into an L-shape.
[0037]
Both side edge portions 43, 43 of the clamping portion 40 are respectively a stealing portion 44 provided continuously with the restricting portion 41, a top portion 45 provided continuously with the stealing portion 44, and a tapered portion 47 provided continuously with the top portion 45. And a stealing portion 48 disposed between the tapered portion 47 and the pressing portion 42. The tapered portion 47 is formed so that the width dimension of the sandwiching portion 40 gradually decreases from the restricting portion 41 to the pressing portion.
[0038]
The restricting portion 41 has jaw portions (ear portions) 41 a and 41 a that protrude to the left and right rather than the left and right width of the sandwiching portion 40. The pressing portion 42 has bent portions 46 and 46 whose left and right end portions of the tip edge portion are bent in a direction opposite to that of the regulating portion 41 in a plan view. It has knee portions 42a, 42a projecting left and right rather than the left and right widths.
[0039]
FIG. 11 to FIG. 14 show a state in which the diameter-enlarged piece 4 is clamped by the fastening ring 3, the clamping part 40 is held by the slit 30, and the regulating part 41 is the axis of the fastening ring 3. Is protruded outward in the direction and is in contact with the side edge 31 of the tightening ring 3 to restrict the clamping position, and the pressing portion 42 is protruded in the inner diameter direction of the tightening ring 3 and tightened. It contacts the inner peripheral surface 33 of the ring body 3 and abuts on the tip of the pipe 1 to be inserted. Further, the top portions 45, 45 of the side edge portions 43, 43 of the sandwiching portion 40 are in contact with both end edge portions 34, 34 forming the slit 30 of the fastening ring 3 in a dot or line shape.
[0040]
At this time, as shown in FIG. 13, the diameter-expanded piece 4 is drawn into the slit 30 inside by the gap 30a of the slit 30 whose width dimension is decreasing (as described above with reference to FIG. 7). The jaws 41 a and 41 a of the restricting portion 41 are hooked on the side edge 31 of the tightening ring 3.
[0041]
Further, as shown in FIG. 14, the mutual spacing dimension of the end edge portions 34 of the fastening ring 3 is formed so as to gradually increase in the cross section and the outer diameter side. Although it is pushed out to the outer diameter side of the tightening ring 3, it is caught by the inner peripheral surface 33 of the tightening ring 3 by the knee portions 42 a and 42 a of the pressing portion 42.
[0042]
Therefore, the posture of the enlarged diameter piece 4 can be maintained by the axially inward tensile force applied to the enlarged diameter piece 4 and the pushing force in the outer diameter direction. In short, the diameter-expanded piece 4 is not easily detached due to dropping of the tightening ring 3 during the operation. Note that the stealed portions 44 and 48 of the clamping portion 40 prevent the side edge portions and the inner diameter side edge portions of the end edge portions 34 and 34 of the tightening ring 3 from coming into contact with the enlarged diameter piece 4, thereby expanding The diameter piece 4 can be reliably held.
[0043]
Further, as shown in FIG. 14, the arc-shaped pressing portion 42 is disposed along the insertion tube portion 20 of the joint body 2 in a close state, so that the contact area with the tip surface of the pipe 1 is large. Thus, the pipe 1 can reliably press the diameter-expanded piece 4.
[0044]
Next, the operation (function) of connecting the pipe 1 by the main pipe joint J will be described. That is, as shown in FIG. 1, when the pipe 1 is inserted into the main pipe joint J, the tip of the pipe 1 is bent at the pressing portion 42 of the enlarged diameter piece 4 as shown in FIG. The portion 46 is brought into contact with the force point P to press the diameter-expanding piece 4, and the diameter-expanding piece 4 swings (rotates) around the fulcrum S while the clamping portion 40 and the tightening ring 3 (end) The action point N with which the edge 34) comes into contact moves so as to come out of the clamping ring 3. The force point P refers to a portion where the pipe 1 first contacts the pressing portion 42, and the fulcrum S refers to the restriction portion 41 (jaw portion 41 a) which contacts the side edge 31 of the tightening ring 3. The (point of engagement) portion is referred to, and the action point N refers to a portion where the clamping portion 40 is particularly strongly held by the tightening ring 3.
[0045]
At this time, since the distance R between the fulcrum S and the force point P is sufficiently longer than the distance r between the fulcrum S and the action point N, the tightening ring with a small pressing force of the pipe 1 according to the lever principle. The diameter-enlarged piece 4 that is fastened to 3 with a strong fastening force can be easily moved. That is, since the bent portion 46 that is bent toward the inserted pipe 1 is provided at the inner diameter direction end portion of the pressing portion 42, a force necessary for the initial movement until the diameter-expanding piece 4 starts to rotate is reduced. Can work in the farthest part.
[0046]
The distance R between the fulcrum S and the force point P is preferably set to 3 to 10 times the distance r between the fulcrum S and the action point N, and the diameter-expanding piece 4 can be formed in an appropriate size. The pressing force of 1 can be reduced. That is, when the distance R is set to be less than three times the distance r, it is necessary to increase the pressing force of the pipe 1, and there is a possibility that the diameter-expanded piece 4 will not be detached simply by deforming the tip surface of the plastic pipe 1. On the other hand, if the distance R is set to be more than 10 times the distance r, the diameter-enlarged piece 4 becomes larger than necessary, and the cylindrical cover member 5 becomes unnecessarily large.
[0047]
Then, as the diameter-expanding piece 4 rotates, the tip of the pipe 1 shifts from the (initial) power point P to the final power point Q as shown in FIG. As shown in FIG. 15 (c), the piece 4 is pressed, the diameter-expanding piece 4 is detached from the fastening ring 3, and the pipe 1 is fastened with the fastening ring 3 as shown in FIG. Thus, the pipe 1 can be connected to the joint body 2. The distance T between the fulcrum S and the final force point Q shown in FIG. 15B is smaller than the distance R between the fulcrum S and the force point P shown in FIG. However, in general, since the dynamic friction coefficient is smaller than the static friction coefficient, there is no problem because once the diameter-expanding piece 4 starts to move, the diameter-expanding piece 4 can be sufficiently moved with a small force.
[0048]
According to the tightening ring 3 and the diameter-enlarging piece 4 configured as described above, the diameter-enlarging piece 4 is not easily detached from the tightening ring 3 due to an impact such as a drop, but a small push by inserting the pipe 1 The diameter-enlarged piece 4 can be easily detached from the tightening ring 3 by pressure. That is, conflicting demands can be satisfied at the same time.
[0049]
In addition, this invention is not limited to the above-mentioned embodiment, For example, the shape of the fastening ring body 3 and the diameter expansion piece 4 is not restricted to this embodiment, and various design changes are possible.
[0050]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
[0051]
(According to claim 1) By rotating the transparent cylindrical cover member 5, the enlarged diameter piece 4 can be directed to an easily viewable position, and the enlarged diameter piece 4 is flying from any external position. It is possible to check visually whether or not it is possible to prevent pipe connection failure.
[0052]
(According to claim 2) Before the pipe insertion and connection, the cylindrical cover member 5 can be rotated in advance around the shaft center so that the diameter-expanding piece 4 can be disposed at a desired easy-to-see position. The pipe 1 can be inserted while visually confirming that the pieces 4 fly, and the connection failure of the pipe 1 can be prevented.
(According to claim 3) After the pipe insertion and connection, the cylindrical cover member 5 can be rotated around the axis, and it can be visually confirmed whether or not the expanded diameter piece 4 is flying. 1 connection failure can be prevented. In short, the check after pipe connection construction becomes easy.
(According to claim 4) Before the pipe connection and after the pipe connection, it becomes easier to find the enlarged diameter piece 4, and the pipe connection failure can be more reliably prevented.
[0053]
(According to claim 5) Since the diameter of the tightening ring 3 can be expanded in a perfect circle shape, the pipe 1 can be smoothly inserted into the tightening ring 3 whose diameter has been expanded. Pipe connection work can be easily performed.
(According to claim 6) With the tightening force of the tightening ring 3, the diameter-enlarging piece 4 can be drawn toward the tightening ring 3 side, and the diameter-enlarging piece 4 is securely attached to the tightening ring 3. While being able to assemble | attach, the assembly | attachment attitude | position of the diameter expansion piece 4 can be hold | maintained.
[0054]
(According to claim 7) The diameter-enlarging piece 4 is held by the restricting portion 41 in the axial direction of the tightening ring 3, and the diameter of the tightening ring 3 by the pressing portion 42. The expanded diameter piece 4 is not easily detached from the tightening ring 3 even in the event of an impact such as dropping during operation, and the expanded diameter piece 4 is inadvertent before the pipe 1 is connected. Can be prevented from leaving.
[0055]
(According to claim 8), the holding posture of the enlarged diameter piece 4 by the tightening ring 3 can be further stabilized, and the enlarged diameter piece 4 can be easily detached by pressing the pipe 1. That is, it is possible to prevent the diameter-expanding piece 4 from being detached due to an impact such as a drop during the work, and to improve the connection work of the pipe 1.
(According to claim 9) Since the rotational moment can be increased, even if the pipe 1 is inserted with a light force, the diameter-expanding piece 4 can be reliably detached. Further, the pipe 1 can be brought into contact with the diameter-expanding piece 4 early.
[0056]
(According to claim 10) Since the rotational moment can be increased without increasing the members such as the diameter-expanding piece 4, etc., the pipe joint can be made compact and made of plastic (soft). The diameter-enlarged piece 4 can be ejected (removed) with the tip of the pipe 1, and the pipe 1 can be connected reliably and quickly.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.
FIG. 2 is a longitudinal sectional view showing a state where a pipe is inserted.
FIG. 3 is a cross-sectional view that also serves to explain the operation.
FIG. 4 is a cross-sectional view that also serves to explain the operation.
FIG. 5 is a side view of a tightening ring.
6 is a cross-sectional view taken along the line AA in FIG.
FIG. 7 is an enlarged view of a main part of the tightening ring.
FIG. 8 is a plan view of an enlarged diameter piece.
FIG. 9 is a rear view of the enlarged diameter piece.
FIG. 10 is a development view of the diameter-expanded piece.
FIG. 11 is a side view of the tightening ring in a state where the diameter-enlarged piece is clamped.
12 is a cross-sectional view taken along the line BB in FIG.
FIG. 13 is an operation explanatory diagram of a diameter-enlarging piece that is sandwiched between fastening rings.
FIG. 14 is an operation explanatory view of a diameter-enlarging piece sandwiched between fastening rings.
FIG. 15 is an operation explanatory view showing a detached state of the diameter-expanded piece.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pipe 2 Joint main body 3 Fastening ring 4 Diameter expansion piece 5 Cylindrical cover member 6 Inner peripheral surface 7 Small protrusion part
20 Insertion tube
30 slits
30a gap
31 Side edge
32 Tanibe
33 Inner peripheral surface
34 Edge
40 Clamping part
41 Regulatory Department
42 Pressing part
43 Side edge
44 Thief
45 Top
46 Bending part K Axial positioning mechanism S Support point P Force point N Action point R Distance r Distance

Claims

The joint body 2 having the insertion cylinder portion 20 inserted into the end portion of the pipe 1 to be connected and the end portion of the pipe 1 externally fitted to the insertion cylinder portion 20 are tightened with a resilient tightening force. A tightening ring 3 with a slit 30 and a releasably inserted into the slit 30 so as to expand the diameter of the tightening ring 3 against the elastic force of the tightening ring 3 The enlarged diameter piece 4 that comes into contact with and disengages from the tip of the pipe 1 that is inserted and surrounds the fastening ring 3 that holds the enlarged diameter piece 4 and rotates around the joint body 2 And a transparent tubular cover member 5 that is freely fitted over the pipe joint.

The tightening ring 3 holding the diameter-expanding piece 4 is restrained from moving in the axial direction inside the cylindrical cover member 5 via the axial positioning mechanism K, together with the cylindrical cover member 5. The pipe joint according to claim 1, wherein the pipe joint is provided so as to rotate about an axis.

A plurality of small protrusions 7 are provided on the inner peripheral surface 6 of the cylindrical cover member 5 so that the diameter-enlarged piece 4 detached from the fastening ring 3 rotates with the cylindrical cover member 5. The pipe joint according to claim 1 or 2.

The pipe joint according to claim 1, 2 or 3, wherein the expanded diameter piece 4 has a conspicuous color.

The pipe joint according to claim 1, 2, 3, or 4, wherein both side edge portions 31, 31 of the tightening ring 3 have a plurality of valley portions 32, which are gradually deepened toward the slit 30. .

The diameter-enlarging piece 4 is assembled so as to be sandwiched by one gap portion 30a at both ends of the slit 30 of the tightening ring 3, and the width dimension of the one gap portion 30a is increased in the lateral direction. 6. A pipe joint according to claim 1, wherein said pipe joint is formed so as to gradually decrease.

The enlarged diameter piece 4 protrudes outward in the axial direction of the clamping ring 3 and the clamping portion 40 held by the slit 30 in a state where the enlarged diameter piece 4 is clamped by the clamping ring 3. And a restricting portion 41 that is in contact with the side edge 31 of the tightening ring 3 and restricts the clamping position, and is protruded in the inner diameter direction of the tightening ring 3 so as to protrude from the inner periphery of the tightening ring 3. The pipe joint according to claim 1, 2, 3, 4, 5 or 6, further comprising a pressing portion 42 that contacts the surface 33 and abuts against a tip portion of the pipe 1 to be inserted.

Both side edge portions 43, 43 of the sandwiching portion 40 have a stealing portion 44, 44 connected to the restriction portion 41, and a top portion 45, 45 connected to the stealing portion 44, 44, the top portion 45, The pipe joint according to claim 7, wherein 45 is in point or linear contact with both end edges 34, 34 forming the slit 30 of the tightening ring 3.

The pipe joint according to claim 7 or 8, wherein the pressing portion has a bent portion that is bent toward the pipe 1 into which the inner diameter direction end portion is inserted.

In the longitudinal section, the diameter-enlarging piece 4 is a portion where the restricting portion 41 contacts the side edge 31 of the tightening ring 3 and the fulcrum S serving as the oscillation center of the diameter-enlarging piece 4 and the pipe 1 Has a force point P that is a portion that first contacts the pressing portion 42 and an action point N where the clamping portion 40 and the fastening ring 3 come into contact, and the distance R between the fulcrum S and the force point P is the fulcrum. The pipe joint according to claim 7, wherein the pipe joint is set to be 3 to 10 times the distance r between S and the action point N.