JP4270666B2

JP4270666B2 - Pipe joint structure

Info

Publication number: JP4270666B2
Application number: JP22848199A
Authority: JP
Inventors: 保前西; 昭人戸継
Original assignee: Waterworks Technology Development Organization Co Ltd
Current assignee: Waterworks Technology Development Organization Co Ltd
Priority date: 1999-08-12
Filing date: 1999-08-12
Publication date: 2009-06-03
Anticipated expiration: 2019-08-12
Also published as: JP2001056080A

Description

【０００１】
【発明の属する技術分野】
本発明は、受口管部に挿入接続された合成樹脂製の挿入管部の外周面と前記受口管部の内周面との間、又は、前記挿入管部に外装する状態で受口管部に管軸芯方向から固定連結される押輪の内周面と前記挿入管部の外周面との間に、挿入管部の外周面に喰い込み可能な抜止部材を設け、前記受口管部と挿入管部との相対離脱移動に連れて抜止部材を縮径側に変位させるカム手段を設けるとともに、前記挿入管部内の先端から少なくとも抜止部材の喰い込み作用箇所に相当する部位又はその近くまでの領域に補強筒体を内嵌してある管継手構造に関する。
【０００２】
【従来の技術】
この種の管継手構造では、地震や不同沈下等に起因して受口管部と挿入管部とに離脱方向への外力（管軸芯方向での引張力）が作用しても、受口管部と挿入管部との管軸芯方向での相対離脱移動に連れて抜止部材がカム手段によって縮径側に変位されるため、抜止部材が挿入管部の外周面により深く喰い込むことになり、その結果、受口管部と挿入管部との離脱抵抗が増大する。
しかも、挿入管部が鋳鉄等に比して管軸芯方向の伸び特性及び撓み特性に勝れたポリエチレン等の合成樹脂で製作されているから、地震や不同沈下等に起因する管軸芯方向の引張力や曲げモーメント等の外力を、挿入管部自体の伸び特性及び撓み特性を利用して吸収することができる。
更に、抜止部材の縮径側への変位に連れて合成樹脂製の挿入管部に作用する締付け力が増大しても、この増大する締付け力を、挿入管部に内嵌した補強筒体にて受止めることができるから、抜止部材の締付け力による挿入管部の径方向内方への変形を抑制することができる。
それ故に、離脱抵抗の増大と挿入管部による外力吸収作用及び挿入管部の径方向での変形抑制作用との相乗によって、受口管部からの挿入管部の離脱防止機能を高めることができる。
【０００３】
そして、このような利点を有する管継手構造において、従来では、組付け作業途中での振動や衝撃或いは輸送流体の流速等に起因する補強筒体の位置ずれを抑制するために、挿入管部に挿入される補強筒体の内嵌筒部の外径を、それの管軸芯方向の全域に亘って挿入管部の内径よりも大に構成して、該補強筒体を挿入管部内に圧入固定していた（例えば、実公平５−９５８２号公報参照）。
【０００４】
【発明が解決しようとする課題】
従来の管部継手構造では、補強筒体の外径がそれの管軸芯方向の全域に亘って挿入管部の内径よりも大に構成されているため、圧入時に、挿入管部の内周面と補強筒体の外周面との間での摩擦抵抗力が強大となり、挿入管部に対して補強筒体を人為操作で圧入する場合には、その圧入作業に多大の労力と時間を要し、また、機械力を利用して補強筒体を挿入管部に圧入する場合では、圧入装置が大型化し易い欠点がある。
【０００５】
特に、挿入管部に圧入される補強筒体の管軸芯方向での嵌合長さが長くなればなる程、圧入作業能率の低下を招来し易く、更に、合成樹脂製の挿入管部の場合では、内径側での寸法公差が鋳鉄製の挿入管部に比して大きいため、補強筒体の内嵌筒部における外径の寸法公差が大径側に、かつ、挿入管部の内径の寸法公差が小径側にそれぞれ片寄った場合には、挿入管部に対する補強筒体の圧入力が著しく増大し、前述の欠点を一層助長し易い。
【０００６】
そこで、本発明者は種々の実験を行ったところ、補強筒体の内嵌筒部の外周面全体が挿入管部の内周面に圧接されていなくても、つまり、挿入管部の内周面とこれに内嵌された補強筒体の内嵌筒部の外周面との間に隙間があっても、外力に起因する受口管部と挿入管部との相対離間移動によって、抜止め部材が縮径側に変位されたとき、或いは、人為操作で抜止め部材を縮径側に変位させたときには、挿入管部の内周面が補強筒体の内嵌筒部の外周面に圧接して、該補強筒体による径方向での変形を抑制する効果が得られることを知見した。
【０００７】
本発明の主たる課題は、上述の知見に基づいた補強筒体の合理的な改造により、受口管部と挿入管部との離脱の一因となる挿入管部の変形を抑制しながら、組付け作業途中での振動や輸送流体の流速等に起因する補強筒体の位置ずれを抑制することができ、しかも、合成樹脂製の挿入管部の内径寸法が大きな公差範囲内で変動する条件下でも、挿入管部に対する補強筒体の内嵌作業を少ない労力で能率良く確実に行うことができる管継手構造を提供する点にある。
【０００８】
【課題を解決するための手段】
本発明の請求項１による特徴構成は、受口管部に挿入接続された合成樹脂製の挿入管部の外周面と前記受口管部の内周面との間、又は、前記挿入管部に外装する状態で受口管部に管軸芯方向から固定連結される押輪の内周面と前記挿入管部の外周面との間に、挿入管部の外周面に喰い込み可能な抜止部材を設け、前記受口管部と挿入管部との相対離脱移動に連れて抜止部材を縮径側に変位させるカム手段を設けるとともに、前記挿入管部内の先端から少なくとも抜止部材の喰い込み作用箇所に相当する部位又はその近くまでの領域に補強筒体を内嵌してある管継手構造であって、
前記挿入管部に内嵌される補強筒体の内嵌筒部の外径を、前記挿入管部の内径よりも小に構成するとともに、前記補強筒体のうち、内嵌時に挿入管部の先端部に対応する部位又はその近くには、挿入管部の内周面よりも径方向の外方に突出位置し、かつ、挿入管部内への挿入に連れて径方向内方に弾性変形する抜止め部を形成し、更に、前記抜止め部の径方向外方への突出代を周方向で異ならせた点にある。
【０００９】
上記特徴構成によれば、前記挿入管部の内周面とこれに内嵌された補強筒体の内嵌筒部の外周面との間に隙間があっても、地震や不同沈下等の外力に起因する受口管部と挿入管部との相対離間移動によって、抜止め部材がカム手段によって縮径側に変位されたとき、或いは、人為操作で抜止め部材をカム手段によって縮径側に変位させたとき、挿入管部の内周面が補強筒体の内嵌筒部の外周面に圧接されれば、挿入管部の径方向内方への変形を効果的に抑制することができることを知見し、その変形抑制効果が得られる範囲内において、前記補強筒体の内嵌筒部の外径を挿入管部の内径よりも小に構成することにより、挿入管部に対する補強筒体の内嵌作業時の挿入抵抗を軽減することができる。
【００１０】
それでいて、補強筒体の内嵌筒部が挿入管部内の所定位置に内嵌された状態では、補強筒体に形成してある抜止め部が、挿入管部の内周面との接当によって径方向内方に弾性変形して、それの弾性復帰力で抜止め部が挿入管部に圧接されて摩擦抵抗力が生じるから、組付け作業途中での振動や衝撃或いは輸送流体の流速等に起因する補強筒体の位置ずれを抑制することができる。
【００１１】
しかも、前記抜止め部の径方向外方への突出代を周方向で異ならせてあるから、径方向外方への突出代が最大となる部位をもって、挿入管部の寸法公差範囲内での最大内径に対応させ、かつ、径方向外方への突出代が最小となる部位をもって、挿入管部の寸法公差範囲内での最小内径に対応させることが可能で、例えば、前記抜止め部の径方向外方への突出代が周方向で同一に構成されている場合に比して、補強筒体の内嵌作業時の挿入抵抗を軽減することができる。
【００１２】
従って、受口管部と挿入管部との離脱の一因となる挿入管部の変形を抑制しながら、組付け作業途中での振動や衝撃或いは輸送流体の流速等に起因する補強筒体の位置ずれを抑制することができ、しかも、合成樹脂製の挿入管部の内径寸法が大きな公差範囲内で変動する条件下でも、挿入管部に対する補強筒体の内嵌作業を少ない労力で能率良く確実に行うことができる。
【００１３】
本発明の請求項２による管部継手構造の特徴構成は、前記抜止め部が、補強筒体の周方向複数箇所を径方向外方に折曲げて形成された径方向内方に弾性変形可能な抜止め片から構成されているとともに、前記抜止め片が、径方向外方への突出代が異なる二種類以上の突出代に構成されている点にある。
【００１４】
上記特徴構成によれば、前記抜止め部を構成する複数の抜止め片が、補強筒体自体の径方向外方への折曲げによって構成されているから、例えば、前記抜止め部を、バネ材や合成ゴム等の弾性材料で製作された抜止め体から構成して、該抜止め体を補強筒体の外周面に固着する場合に比して、前記抜止め部を備えた補強筒体の製造コストの低廉化を図ることができるばかりでなく、所期の抜止め機能を長期に亘って確実に発揮させることができる。
【００１５】
本発明の請求項３による管部継手構造の特徴構成は、前記抜止め片のうち、径方向外方への突出代が大きい抜止め片の周方向幅が、径方向外方への突出代が小さい抜止め片の周方向幅よりも小幅に構成されている点にある。
【００１６】
上記特徴構成によれば、前記抜止め部を構成する複数の抜止め片のうち、径方向外方への突出代が最大となる抜止め片をもって、挿入管部の寸法公差範囲内での最大内径に対応させ、かつ、径方向外方への突出代が最小となる抜止め片をもって、挿入管部の寸法公差範囲内での最小内径に対応させることが可能となる。しかも、突出代の大きな抜止め片の周方向幅を小に構成することによって、挿入管部の内径が寸法公差範囲内で最小にあるときでも、最も径方向内方への弾性変形量が大きくなる大突出側の抜止め片の弾性変形に要する操作力が小さくて済む。
【００１７】
それ故に、例えば、前記抜止め部を構成する複数の抜止め片の径方向外方への突出代が周方向で同一に構成され、かつ、各抜止め片の周方向幅も同一に構成されている場合に比して、合成樹脂製の挿入管部の内径寸法が大きな公差範囲内で変動する条件下でも、挿入管部に対する補強筒体の内嵌作業をより少ない労力で能率良く確実に行うことができる。
【００１８】
本発明の請求項４による管部継手構造の特徴構成は、前記抜止め片の周方向両側縁が、径方向外方にエッジが突出する状態に折曲げ形成されている点にある。上記特徴構成によれば、前記補強筒体の内嵌筒部が挿入管部内の所定位置に内嵌されるに連れて、補強筒体の周方向複数箇所に折曲げ形成された抜止め部の抜止め片が、挿入管部の内周面との接当によって径方向内方に弾性変形しながら圧接され、しかも、このとき、各抜止め片の周方向両側縁に形成されたエッジが挿入管部の内周面に喰込むことになるから、組付け作業途中での振動や衝撃或いは輸送流体の流速等に起因する補強筒体の位置ずれをより効果的に抑制することができる。
しかも、前記抜止め片の折曲げ加工によって該抜止め片のエッジを径方向外方に突出させるから、例えば、前記抜止め片の外周面に、補強筒体の内嵌筒部が挿入管部内の所定位置に内嵌されるに連れて、挿入管部の内周面に喰込む喰込み部を突出形成する場合に比して、喰込み部を備えた補強筒体の製造コストの低廉化を図ることができる。
【００１９】
本発明の請求項５による管部継手構造の特徴構成は、前記抜止め片のうち、少なくとも径方向外方への突出代が小さい抜止め片の端縁に、挿入管部内への挿入に連れてそれの弾性復元力で挿入管部の内周面に圧接されるエッジが形成されている点にある。
【００２０】
上記特徴構成によれば、挿入管部の内径が公差範囲の大径側に片寄った状態にある場合では、径方向外方への突出代が大きい抜止め片が主体になって抜止め機能が発揮されるが、この場合でも、突出代の小さな抜止め片の端縁に形成されたエッジが、挿入管部の内周面に弾性的に圧接されているときには、挿入管部と補強筒体との相対移動抵抗が増大し、組付け作業途中での振動や衝撃或いは輸送流体の流速等に起因する補強筒体の位置ずれを一層効果的に抑制することができる。
【００２１】
【発明の実施の形態】
〔第１実施形態〕
図１〜図１１は、鋳鉄製の継手本体Ａの受口管部１に、合成樹脂製の流体輸送管の一例であるポリエチレン製の水道管Ｐの一端側の挿入管部２を密封状態で挿入接続するための本発明の管継手構造を示し、前記受口管部１の内周面１ａに、管軸芯Ｘ方向での溝幅が異なる二つの環状溝１Ａ，１Ｂを形成し、そのうち、受口側に位置する溝幅の小さな第１環状溝１Ａ内には、受口管部１の内周面１ａと挿入管部２の外周面２ａとの間を密封する第１弾性シール材３を装着するとともに、奥側に位置する溝幅の大きな第２環状溝１Ｂ内には、受口管部１に挿入接続された挿入管部２の外周面２ａに喰い込み可能な抜止部材の一例で、弾性的に縮径変形可能なほぼＣの字状に形成された合成樹脂製（例えば、ポリアセタール等）又は金属製（例えば、ステンレス鋼等）の抜止めリング４と、該抜止めリング４よりも奥側位置において、受口管部１の内周面１ａと挿入管部２の外周面２ａとの間を密封する第２弾性シール材５とを装着してある。
【００２２】
前記受口管部１の内周面１ａのうち、前記第２環状溝１Ｂ内に位置する周面には、図１、図７、図１１に示すように、受口管部１と挿入管部２との管軸芯Ｘ方向での相対離脱移動に連れて抜止めリング４を縮径側に変位させる、つまり、抜止めリング４を、それの弾性復元力に抗して縮径変形させるカム手段としてのテーパー状のカム面６を形成するとともに、前記挿入管部２内の先端から少なくとも抜止めリング４の喰い込み作用箇所に相当する部位又はその近くまでの領域（当該第１実施形態では、前記挿入管部２のうち、受口管部１内に挿入される管部分よりも少し長い領域）に、抜止めリング４の縮径変形に伴う挿入管部２の径方向内方への変形を抑制するステンレス鋼製（金属製）の補強筒体７を内嵌してある。
【００２３】
前記補強筒体７のうち、挿入管部２に内嵌される内嵌筒部７Ａの外径Ｄ１を、前記挿入管部２の内径Ｄ２よりも小に構成する、詳しくは、挿入管部２の公差範囲内での最小内径Ｄ２よりも僅かに小に構成するとともに、前記補強筒体７の先端部分７ｄを、先端側ほど小径となるテーパー状に絞り形成してある。
更に、前記補強筒体７のうち、内嵌時に挿入管部２の先端部に対応する部位又はその近く（当該実施形態では、挿入管部２内の所定位置に内嵌した状態で該挿入管部２の先端部に対応する基端部分７ｅ）には、挿入管部２の内周面２ｃよりも径方向の外方に突出位置し、かつ、挿入管部２内への挿入に連れて径方向内方に弾性変形する抜止め部７Ｂを形成するとともに、前記抜止め部７Ｂの径方向外方への突出代を周方向で異ならせてある。
【００２４】
つまり、前記抜止め部７Ｂは、図２、図３に示すように、補強筒体７の基端部分７ｅで、かつ、その周方向４箇所に形成されたＶ字状のスリット７ａの隣接間に位置する部分を径方向外方に折曲げて形成された径方向内方に弾性変形可能な抜止め片７ｂから構成されているとともに、前記抜止め片７ｂが、径方向外方への突出代が異なる二種類の突出代に構成されている。
【００２５】
前記抜止め片７ｂのうち、径方向外方への突出代が大きい抜止め片７ｂの周方向幅Ｗ１が、径方向外方への突出代が小さい抜止め片７ｂの周方向幅Ｗ２よりも小幅に構成されているとともに、径方向外方への突出代が大きい抜止め片７ｂ同士及び径方向外方への突出代が小さい抜止め片７ｂ同士がそれぞれ筒軸芯（管軸芯Ｘ）を通る径方向で相対向するように、突出代の大きいものと小さいものとが周方向で交互に配置されている。
【００２６】
前記抜止め片７ｂのうち、径方向外方への突出代が最大となる抜止め片７ｂをもって、挿入管部２の寸法公差範囲内での最大内径に対応させ、かつ、径方向外方への突出代が最小となる抜止め片７ｂをもって、挿入管部２の寸法公差範囲内での最小内径に対応させるように構成してある。
つまり、図４〜図７に示すように、挿入管部２の内径Ｄ２が寸法公差範囲内での最大径となっている場合には、径方向外方への突出代が最大となる一対の抜止め片７ｂのみが径方向内方に弾性変形して、挿入管部２内の所定領域に内嵌された補強筒体７を抜止め保持し、また、図８〜図１１に示すように、挿入管部２の内径Ｄ２が寸法公差範囲内での最小径となっている場合には、全ての抜止め片７ｂが径方向内方に弾性変形するものの、主として、径方向外方への突出代が最小となる一対の抜止め片７ｂにより、挿入管部２内の所定領域に内嵌された補強筒体７を抜止め保持する。
【００２７】
更に、前記抜止め片７ｂのうち、径方向外方への突出代が小さい抜止め片７ｂの端縁には、挿入管部２内への挿入に連れてそれの弾性復元力で挿入管部２の内周面２ｃに圧接されるエッジ７ｃが形成されている。
そして、挿入管部２の内径Ｄ２が公差範囲の大径側に片寄った状態にある場合では、径方向外方への突出代が大きい抜止め片７ｂが主体になって抜止め機能が発揮されるが、この場合でも、突出代の小さな抜止め片７ｂの端縁に形成されたエッジ７ｃが、挿入管部２の内周面２ｃに弾性的に圧接されているときには、挿入管部２と補強筒体７との管軸芯Ｘ方向での相対移動抵抗が増大し、組付け作業途中での振動や衝撃或いは水（流体）の流動（流速）等に起因する補強筒体７の位置ずれを一層効果的に抑制することができる。
【００２８】
前記抜止めリング４の内周面には、挿入管部２の外周面２ａに喰い込み可能な多数の喰込み突起４ａが形成されているとともに、前記抜止めリング４の外周面４ｂは、前記カム面６に沿うテーパー面に形成されている。
また、前記該抜止めリング４のテーパー状外周面４ｂとカム面６とが接当していない状態でも、抜止めリング４の縮径側への弾性復元力によって、それの喰込み突起４ａが挿入管部２の外周面２ａに僅かに喰い込むように構成されているとともに、前記挿入管部２の先端部には、挿入管部２の挿入に連れて抜止めリング４を弾性復元力に抗して拡径変形させるためのテーパー状の第２カム面２ｂが形成されている。
【００２９】
前記継手本体Ａの受口管部１の他端部には、他の配管や仕切弁等の管継手具等に設けられたフランジ部１０に対してボルト１１・ナット１２を介して連結されるフランジ部１３が一体形成されている。
【００３０】
そして、前記挿入管部２内の所定領域に亘って補強筒体７の内嵌筒部７Ａを内嵌した状態で、図６及び図１０に示すように、前記挿入管部２の内周面２ｃとこれに内嵌された補強筒体７の内嵌筒部７Ａの外周面との間に隙間があっても、図７及び図１１に示すように、地震や不同沈下等による外力に起因して受口管部１と挿入管部２とが相対離間移動すると、カム手段としてのテーパー面６によって抜止めリング４が縮径変形され、それに連れて挿入管部２が径方向内方に縮径変形されて、挿入管部２の内周面２ｃが補強筒体７の内嵌筒部７Ａの外周面に圧接されるから、それ以降の挿入管部２の径方向内方への変形を抑制することができる。
【００３１】
〔第２実施形態〕
図１２、図１３は、鋳鉄製の継手本体Ａの受口管部１に、合成樹脂製の流体輸送管の一例であるポリエチレン製の水道管Ｐの挿入管部２を密封状態で挿入接続するための管継手構造の別実施形態を示し、前記挿入管部２に、受口管部１の内周面１ａと挿入管部２の外周面２ａとの間を密封可能な合成ゴム製（例えば、スチレンブタジエンゴム）の弾性シール材２０と、該弾性シール２０を管軸芯Ｘ方向から押圧して密封状態（水密状態）にまで圧縮可能な鋳鉄製の押輪２１とを外装するとともに、前記押輪２１と受口管部１とを管軸芯Ｘ方向から締付け固定連結する締結手段２２を設けてある。
【００３２】
前記押輪２１の内周面２１ａと挿入管部２の外周面２ａとの間には、挿入管部２の外周面２ａに喰い込み可能な抜止部材の一例で、管軸芯Ｘ方向において弾性的に縮径変形可能なほぼＣの字状に形成された合成樹脂製（例えば、ポリアセタール等）又は金属製（例えば、ステンレス鋼等）の抜止めリング４を設けるとともに、前記押輪２１の内周面２１ａには、前記締結手段２２の締付け操作に伴う押輪２１と受口管部１との相対近接移動に連れて前記抜止めリング４を縮径側に変位させる、つまり、抜止めリング４をそれの弾性復元力に抗して縮径変形させるカム手段の一例で、受口管部１側ほど大径となるテーパー状のカム面６を形成してある。
【００３３】
前記弾性シール材２０とこれに対して管軸芯Ｘ方向で対向する押輪２１及び抜止めリング４との間には、前記締結手段２２による締付け操作の前半で弾性シール材２０のみを押圧圧縮し、該弾性シール材２０が設定圧縮状態になった以降の締付け操作で、前記カム面６により抜止めリング４を喰い込み状態にまで前記弾性復元力に抗して縮径変形させる順次作動手段２３を設けてある。
【００３４】
更に、前記抜止めリング４が挿入管部２の外周面２ａに少し喰い込んでいる状態において、挿入接続された受口管部１と挿入管部２とに離脱方向への外力（管軸芯Ｘ方向での引張力）が作用して、受口管部１と挿入管部２とが相対離脱移動すると、これに連れて抜止めリング４のテーパー状外周面４ｂがカム面６に押圧されて縮径変形し、抜止めリング４の喰込み突起４ａが挿入管部２の外周面２ａに更に喰い込むように構成されている。
【００３５】
そして、前記挿入管部２内の先端から少なくとも抜止めリング４の喰い込み作用箇所に相当する部位又はその近くまでの領域（当該第２実施形態では、前記挿入管部２のうち、受口管部１内に挿入される管部分の長さと押輪２１の管軸芯方向長さとの和よりも少し長い領域）に、抜止めリング４の縮径変形に伴う挿入管部２の径方向内方への変形を抑制するステンレス鋼製（金属製）の補強筒体７を内嵌してある。
【００３６】
前記補強筒体７のうち、挿入管部２に内嵌される内嵌筒部７Ａの外径Ｄ１を、前記挿入管部２の内径Ｄ２よりも小に構成する、詳しくは、挿入管部２の寸法公差範囲内での最小内径Ｄ２よりも僅かに小に構成するとともに、前記補強筒体７の先端部分７ｄを、先端側ほど小径となるテーパー状に絞り形成してある。
更に、前記補強筒体７のうち、内嵌時に挿入管部２の先端部に対応する部位又はその近く（当該実施形態では、挿入管部２内の所定位置に内嵌した状態で該挿入管部２の先端部に対応する基端部分７ｅ）に、挿入管部２の内周面２ｃよりも径方向の外方に突出位置し、かつ、挿入管部２内への挿入に連れて径方向内方に弾性変形する抜止め部７Ｂを形成するとともに、前記抜止め部７Ｂの径方向外方への突出代を周方向で異ならせてある。
つまり、前記抜止め部７Ｂは、補強筒体７の基端部で、かつ、その周方向４箇所に形成されたＶ字状のスリット７ａの隣接間に位置する部分を径方向外方に折曲げて形成された径方向内方に弾性変形可能な抜止め片７ｂから構成されているとともに、前記抜止め片７ｂが、径方向外方への突出代が異なる二種類の突出代に構成されている。
【００３７】
前記抜止め片７ｂのうち、径方向外方への突出代が大きい抜止め片７ｂの周方向幅Ｗ１が、径方向外方への突出代が小さい抜止め片７ｂの周方向幅Ｗ２よりも小幅に構成されているとともに、前記抜止め片７ｂのうち、径方向外方への突出代が小さい抜止め片７ｂの端縁には、挿入管部２内への挿入に連れてそれの弾性復元力で挿入管部２の内周面２ｃに圧接されるエッジ７ｃが形成されている。
【００３８】
前記順次作動手段２３は、前記抜止めリング４と弾性シール材２０との間に、前記押輪２１と受口管部１との相対近接移動に連れて弾性シール材２０を管軸芯Ｘ方向から押圧圧縮する第１押圧面２４ａと、前記抜止めリング４を押輪２１のカム面６側に管軸芯Ｘ方向から押圧可能な第２押圧面２４ｂとを備えたステンレス鋼等の金属製又は合成樹脂製の円環状の中間押圧体２４を設け、この中間押圧体２４と押輪２１の内周面との径方向で対向又はほぼ対向する部位に亘って、前記押輪２１と受口管部１との相対近接移動に連れて前記弾性シール材２０が設定圧縮状態になるまでは、前記押輪２１のカム面６と中間押圧体２４の第２押圧面２４ｂとの管軸芯Ｘ方向での対向間隔を非喰い込み状態にある抜止めリング４が縮径側に弾性変形しない間隔に規制し、かつ、前記弾性シール材２０が設定圧縮状態になったとき、中間押圧体２４の外周面と押輪２１の内周面２１ａとの間で剪断されて前記間隔規制を解除する、つまり、前記押輪２１のカム面６と中間押圧体２４の第２押圧面２４ｂとの管軸芯Ｘ方向での相対近接移動を許す間隔規制部材（銅合金やアルミニウム合金等の金属製の頭付きシヤーピン）２５を設けて構成されている。
【００３９】
前記締結手段２２は、受口管部１の連結フランジ部２６のボルト挿通孔２７と押輪２１の連結突起２８のボルト挿通孔２９とのうち、管軸芯Ｘ方向で相対向する両ボルト挿通孔２７，２９に亘って挿通されるＴ字状のボルト２２Ａとナット２２Ｂとから構成されている。
【００４０】
尚、前記補強筒体７及び抜止めリング４の詳細は、第１実施形態と同一であるため、同一の構成には同一の符号を付記して、それの説明は省略する。
【００４１】
〔第３実施形態〕
前述の各実施形態では、前記抜止め部７Ｂを、補強筒体７の基端部で、かつ、その周方向４箇所に形成されたＶ字状のスリット７ａの隣接間に位置する部分を径方向外方に折曲げて形成された径方向内方に弾性変形可能な抜止め片７ｂから構成したが、図１４に示すように、補強筒体７のうち、その基端から筒軸芯（管軸芯）方向の中央側に偏位した中間部分の周方向複数箇所を、径方向外方に打出し形成して、この打出された径方向内方に弾性変形可能な複数の抜止め片７ｂをもって前記抜止め部７Ｂを構成してもよい。
【００４２】
〔第４実施形態〕
前述の各実施形態では、前記抜止め部７Ｂを、補強筒体７の周方向複数箇所を径方向外方に折曲げて形成された径方向内方に弾性変形可能な抜止め片７ｂから構成するとともに、各抜止め片７ｂの外周面を円弧状に形成したが、図１５に示すように、前記スリット７ａに沿う抜止め片７ｂの周方向両側縁を、径方向外方に向かって第２のエッジ７ｆが突出する状態に折曲げ形成して実施しても良い。この実施形態によれば、前記補強筒体７の内嵌筒部７Ａが挿入管部２内の所定位置に内嵌されるに連れて、補強筒体７の周方向複数箇所に折曲げ形成された抜止め部７Ｂの抜止め片７ｂが、挿入管部２の内周面２ｃとの接当によって径方向内方に弾性変形しながら圧接され、しかも、このとき、各抜止め片７ｂの周方向両側縁に形成された第２エッジ７ｆが挿入管部２の内周面２ｃに喰込むことになるから、組付け作業途中での振動や衝撃或いは輸送流体の流動（流速）等に起因する補強筒体７の位置ずれをより効果的に抑制することができる。
しかも、前記抜止め片７ｂの折曲げ加工によって該抜止め片７ｂの第２エッジ７ｆを径方向外方に突出させるから、例えば、前記抜止め片７ｂの外周面に、補強筒体７の内嵌筒部７Ａが挿入管部２内の所定位置に内嵌されるに連れて、挿入管部２の内周面２ｃに喰込む喰込み部を突出形成する場合に比して、喰込み部を備えた補強筒体７の製造コストの低廉化を図ることができる。
【００４３】
〔その他の実施形態〕
（１）前述の各実施形態では、継手本体Ａとして、受口管部１の管軸芯方向他端側に連結用フランジ部が一体形成されたものを例に挙げて説明したが、この構成に限定されるものではなく、例えば、挿入管部２が各別に挿入接続される一対の受口管部１を備えた継手本体Ａであってもよく、また、このような継手本体Ａの代わりに、仕切弁等の管継手器具の接続口部側に形成されている受口管部であってもよい。
（２）前述の各実施形態では、前記抜止め部７Ｂを、補強筒体７の周方向複数箇所を径方向外方に折曲げ形成された抜止め片７ｂから構成したが、前記抜止め部７Ｂを、バネ材や合成ゴム等の弾性材料で製作された抜止め体から構成して、該抜止め体を補強筒体７の外周面に固着して実施してもよい。
（３）前述の各実施形態では、前記補強筒体７の内嵌筒部７Ａが挿入管部２内の所定位置に内嵌されるに連れて挿入管部２の内周面２ｃに喰込む喰込み部を、突出抜止め片７ｂの周方向両側縁に形成された半径方向外方に突出するエッジ７ｆから構成したが、この喰込み部を、前記抜止め片７ｂの外周面に突出形成される突起から構成してもよい。
（４）前述の各実施形態では、前記抜止めリング４の縮径変形に伴う挿入管部２の径方向内方への変形を抑制する補強筒体７を、挿入管部２内の先端から抜止めリング４の喰い込み作用箇所を超えた広い領域に亘って内嵌したが、この補強筒体７は、挿入管部２内の先端又はその近くから少なくとも抜止めリング４の喰い込み作用箇所相当する部位又はその近くまでの領域に亘って内嵌されていればよい。
（５）前記前述の各実施形態では、前記抜止め片７ｂを、径方向外方への突出代が異なる二種類の突出代に構成したが、径方向外方への突出代が異なる三種類以上の突出代に構成してもよい。
また、径方向外方への突出代が異なる二種類以上の抜止め片７ｂを、突出代の小さなものぼど先端側に位置する状態で管軸芯X方向に位置齟齬させて形成してもよい。
（６）前記各実施形態では、前記補強筒体６を金属の一例であるステンレス鋼から製作したが、合成樹脂から製作しても良い。
【図面の簡単な説明】
【図１】本発明の管継手構造の第１実施形態を示す縦断面図
【図２】補強筒体の斜視図
【図３】補強筒体の正面図
【図４】最大内径にある挿入管部と補強筒体との内嵌途中での弾性変形状態を示す縦断面図
【図５】最大内径にある挿入管部と補強筒体との内嵌完了時の弾性変形状態を示す縦断面図
【図６】挿入管部が最大内径にあるときの管継手の要部の拡大縦断面図
【図７】図６の状態から受口管部と挿入管部とが相対離間移動したときの要部の拡大縦断面図
【図８】最小内径にある挿入管部と補強筒体との内嵌途中での弾性変形状態を示す縦断面図
【図９】最小内径にある挿入管部と補強筒体との内嵌完了時の弾性変形状態を示す縦断面図
【図１０】挿入管部が最小内径にあるときの管継手の要部の拡大縦断面図
【図１１】図１０の状態から受口管部と挿入管部とが相対離間移動したときの要部の拡大縦断面図
【図１２】本発明の管継手構造の第２実施形態を示す縦断面図
【図１３】組付け途中の要部の拡大断面図
【図１４】本発明の管継手構造の第３実施形態を示す補強筒体の縦断面図
【図１５】本発明の管継手構造の第４実施形態を示す補強筒体の一部切欠き正面図
【符号の説明】
１受口管部
１ａ内周面
２挿入管部
２ａ外周面
２ｃ内周面
４抜止部材（抜止めリング）
６カム手段（テーパー面）
７補強筒体
７Ａ内嵌筒部
７Ｂ抜止め部
７ａスリット
７ｂ抜止め片
７ｃエッジ
２１押輪
２１ａ内周面
Ｘ管軸芯[0001]
BACKGROUND OF THE INVENTION
The present invention provides a receiving port between an outer peripheral surface of an insertion tube portion made of a synthetic resin inserted and connected to the receiving tube portion and an inner peripheral surface of the receiving tube portion, or in a state of covering the insertion tube portion. A retaining member capable of biting into the outer peripheral surface of the insertion tube portion is provided between the inner peripheral surface of the press ring fixedly connected to the tube portion from the tube axis direction and the outer peripheral surface of the insertion tube portion, and the receiving tube A cam means for displacing the retaining member to the reduced diameter side in accordance with the relative detachment movement between the insertion tube portion and the insertion tube portion, and at least a portion corresponding to a biting action position of the retaining member from the distal end in the insertion tube portion The present invention relates to a pipe joint structure in which a reinforcing cylinder is fitted in the area up to.
[0002]
[Prior art]
In this type of pipe joint structure, even if an external force (tensile force in the direction of the tube axis) in the direction of separation acts on the receiving pipe part and the insertion pipe part due to an earthquake or uneven settlement, etc. Since the retaining member is displaced to the reduced diameter side by the cam means as the relative separation movement of the tube portion and the insertion tube portion in the axial direction of the tube axis, the retaining member bites deeper into the outer peripheral surface of the insertion tube portion. As a result, the separation resistance between the receiving tube portion and the insertion tube portion increases.
Moreover, since the insertion tube is made of a synthetic resin such as polyethylene, which has superior elongation and deflection characteristics in the tube axis direction compared to cast iron, etc. The external force such as the tensile force and bending moment can be absorbed by utilizing the elongation characteristic and the bending characteristic of the insertion tube part itself.
Furthermore, even if the tightening force acting on the synthetic resin insertion tube portion increases with the displacement of the retaining member toward the reduced diameter side, this increased tightening force is applied to the reinforcing cylinder fitted inside the insertion tube portion. Therefore, deformation of the insertion tube portion inward in the radial direction due to the tightening force of the retaining member can be suppressed.
Therefore, the synergistic effect of the increase in the detachment resistance and the external force absorption action by the insertion pipe part and the deformation suppression action in the radial direction of the insertion pipe part can enhance the function of preventing the detachment of the insertion pipe part from the receiving pipe part. .
[0003]
And in the pipe joint structure having such advantages, conventionally, in order to suppress the displacement of the reinforcing cylinder due to vibration or shock during the assembly operation or the flow velocity of the transport fluid, etc., The outer diameter of the inner fitting cylinder part of the inserted reinforcing cylinder is configured to be larger than the inner diameter of the insertion pipe part over the entire area in the tube axis direction, and the reinforcing cylinder is press-fitted into the insertion pipe part. It was fixed (for example, refer to Japanese Utility Model Publication No. 5-9582).
[0004]
[Problems to be solved by the invention]
In the conventional pipe joint structure, the outer diameter of the reinforcing cylinder is configured to be larger than the inner diameter of the insertion pipe over the entire region in the tube axis direction. The frictional resistance between the surface and the outer peripheral surface of the reinforcing cylinder becomes strong, and when the reinforcing cylinder is press-fitted into the insertion pipe by human operation, it takes a lot of labor and time for the press-fitting work. In addition, when the reinforcing cylinder is press-fitted into the insertion tube portion using mechanical force, there is a drawback that the press-fitting device tends to be large.
[0005]
In particular, the longer the fitting length in the tube axis direction of the reinforced cylindrical body that is press-fitted into the insertion tube part, the easier it is to cause a decrease in the press-fitting work efficiency. In this case, since the dimensional tolerance on the inner diameter side is larger than that of the cast-iron insertion tube portion, the outer diameter dimensional tolerance in the inner tube portion of the reinforcing cylinder is larger, and the inner diameter of the insertion tube portion is larger. When the dimensional tolerances are shifted to the small diameter side, the pressure input of the reinforcing cylindrical body to the insertion pipe portion is remarkably increased, and the above-mentioned defects are further facilitated.
[0006]
Therefore, the present inventor conducted various experiments. As a result, even if the entire outer peripheral surface of the inner tube portion of the reinforcing cylinder is not pressed against the inner peripheral surface of the insertion tube portion, that is, the inner periphery of the insertion tube portion. Even if there is a gap between the surface and the outer peripheral surface of the inner fitting cylinder part of the reinforcing cylinder fitted therein, the retaining pipe part and the insertion pipe part are prevented from being removed by the relative separation movement caused by the external force. When the member is displaced to the reduced diameter side, or when the retaining member is displaced to the reduced diameter side by human operation, the inner peripheral surface of the insertion tube portion is pressed against the outer peripheral surface of the inner tube portion of the reinforcing cylinder. And it discovered that the effect which suppresses the deformation | transformation by the radial direction by this reinforcement cylinder is acquired.
[0007]
The main problem of the present invention is that, by rational modification of the reinforcing cylinder based on the above-mentioned knowledge, the deformation of the insertion pipe part that causes the separation of the receiving pipe part and the insertion pipe part is suppressed. It is possible to suppress the displacement of the reinforced cylinder due to vibration during the attachment process and the flow velocity of the transport fluid, etc., and the condition that the inner diameter dimension of the synthetic resin insertion tube part fluctuates within a large tolerance range However, it is in the point which provides the pipe joint structure which can perform the internal fitting operation | work of the reinforcement cylinder body with respect to an insertion pipe part efficiently and reliably with little effort.
[0008]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a structure between the outer peripheral surface of the synthetic resin insertion tube portion inserted and connected to the receiving tube portion and the inner peripheral surface of the receiving tube portion, or the insertion tube portion. A retaining member that can bite into the outer peripheral surface of the insertion tube portion between the inner peripheral surface of the press ring that is fixedly connected to the receiving tube portion from the tube axis direction and the outer peripheral surface of the insertion tube portion in a state where it is externally mounted. And a cam means for displacing the retaining member to the reduced diameter side in accordance with the relative detachment movement of the receiving tube portion and the insertion tube portion, and at least a portion where the retaining member bites in from the tip in the insertion tube portion A pipe joint structure in which a reinforcing cylinder is internally fitted in a region corresponding to or near the region,
The outer diameter of the inner tube portion of the reinforcing tube body fitted into the insertion tube portion is configured to be smaller than the inner diameter of the insertion tube portion. At a position corresponding to or near the distal end portion, it protrudes radially outward from the inner peripheral surface of the insertion tube portion, and elastically deforms radially inward as the tube is inserted into the insertion tube portion. The retaining portion is formed, and further, the protrusion margin of the retaining portion in the radially outward direction is varied in the circumferential direction.
[0009]
According to the above characteristic configuration, even if there is a gap between the inner circumferential surface of the insertion tube portion and the outer circumferential surface of the inner fitting cylinder portion of the reinforcing cylinder fitted therein, an external force such as an earthquake or non-uniform subsidence is provided. When the retaining member is displaced to the reduced diameter side by the cam means due to the relative separation between the receiving tube portion and the insertion tube portion caused by the above, or the retaining member is moved to the reduced diameter side by the cam means by human operation. When the inner peripheral surface of the insertion tube portion is pressed against the outer peripheral surface of the inner fitting tube portion of the reinforcing cylinder when displaced, it is possible to effectively suppress deformation of the insertion tube portion inward in the radial direction. In the range in which the deformation suppressing effect is obtained, the outer diameter of the inner fitting cylindrical portion of the reinforcing cylindrical body is configured to be smaller than the inner diameter of the inserting pipe portion. The insertion resistance at the time of internal fitting work can be reduced.
[0010]
In addition, in a state where the inner fitting cylinder portion of the reinforcing cylinder body is fitted in a predetermined position in the insertion tube portion, the retaining portion formed in the reinforcement cylinder body is brought into contact with the inner peripheral surface of the insertion tube portion. Since the elastically deformed inward in the radial direction and the retaining part is pressed against the insertion tube by its elastic restoring force, frictional resistance is generated, so vibration or shock during assembly work or flow velocity of transport fluid etc. The resulting displacement of the reinforcing cylinder can be suppressed.
[0011]
In addition, since the allowance for the radially outward protrusion of the retaining portion is different in the circumferential direction, the portion where the allowance for the radially outward protrusion is maximized is within the dimensional tolerance range of the insertion tube portion. It is possible to correspond to the minimum inner diameter within the dimensional tolerance range of the insertion tube portion with a portion corresponding to the maximum inner diameter and having a minimum radially outward projection allowance. The insertion resistance at the time of the internal fitting operation of the reinforcing cylinder can be reduced as compared with the case where the radially outward projecting margin is the same in the circumferential direction.
[0012]
Therefore, while suppressing the deformation of the insertion pipe part that causes the separation of the receiving pipe part and the insertion pipe part, the reinforcing cylinder body is caused by vibration or impact during the assembly operation or the flow velocity of the transport fluid, etc. Position displacement can be suppressed, and even under conditions where the inner diameter of the synthetic resin insertion tube section fluctuates within a large tolerance range, the fitting operation of the reinforcing cylinder to the insertion tube section can be efficiently performed with little effort. It can be done reliably.
[0013]
The pipe joint structure according to claim 2 of the present invention is characterized in that the retaining portion is elastically deformable radially inward formed by bending a plurality of circumferential portions of the reinforcing cylindrical body radially outward. The retaining piece is constituted by two or more kinds of protrusion margins having different protrusion margins in the radially outward direction.
[0014]
According to the above characteristic configuration, since the plurality of retaining pieces constituting the retaining portion are formed by bending the reinforcing cylinder itself outward in the radial direction, for example, the retaining portion may be a spring. Reinforcing cylindrical body provided with the retaining portion as compared with a case where the retaining body is made of a retaining body made of an elastic material such as a material or synthetic rubber, and the retaining body is fixed to the outer peripheral surface of the reinforcing cylindrical body In addition to being able to reduce the manufacturing cost, it is possible to reliably exhibit the desired retaining function over a long period of time.
[0015]
The characteristic structure of the pipe joint structure according to claim 3 of the present invention is that, among the retaining pieces, the circumferential width of the retaining piece having a large radially outward projecting margin is a radially outward projecting margin. Is smaller than the circumferential width of the small retaining piece.
[0016]
According to the above characteristic configuration, of the plurality of retaining pieces constituting the retaining portion, the retaining piece that has the largest radial outward projection allowance is provided, and the maximum within the dimensional tolerance range of the insertion tube portion. It is possible to correspond to the minimum inner diameter within the dimensional tolerance range of the insertion tube portion with the retaining piece that corresponds to the inner diameter and has a minimum protrusion margin in the radially outward direction. In addition, by configuring the circumferential width of the retaining piece having a large protrusion margin to be small, even when the inner diameter of the insertion tube portion is the smallest within the dimensional tolerance range, the amount of elastic deformation in the radially inward direction is the largest. The operating force required for elastic deformation of the large protruding side retaining piece is small.
[0017]
Therefore, for example, the radially outward projection margins of the plurality of retaining pieces constituting the retaining portion are configured to be the same in the circumferential direction, and the circumferential width of each retaining piece is also configured to be the same. Compared to the case where the inner diameter of the insertion tube made of synthetic resin fluctuates within a large tolerance range, the fitting operation of the reinforcing cylinder to the insertion tube can be performed efficiently and reliably with less effort. It can be carried out.
[0018]
The characteristic structure of the pipe joint structure according to claim 4 of the present invention resides in that both side edges in the circumferential direction of the retaining piece are bent so that the edges protrude radially outward. According to the above characteristic configuration, the retaining portion formed by bending at a plurality of locations in the circumferential direction of the reinforcing cylindrical body as the inner cylindrical portion of the reinforcing cylindrical body is internally fitted at a predetermined position in the insertion tube portion. The retaining pieces are pressed against each other while being elastically deformed radially inward by contact with the inner peripheral surface of the insertion tube, and at this time, the edges formed on both circumferential edges of each retaining piece are inserted. Since it will bite into the inner peripheral surface of the pipe part, it is possible to more effectively suppress the displacement of the reinforcing cylinder caused by vibration or impact during the assembly operation or the flow velocity of the transport fluid.
In addition, since the edge of the retaining piece protrudes radially outward by bending the retaining piece, for example, the internal fitting cylinder portion of the reinforcing cylinder is formed in the insertion tube portion on the outer peripheral surface of the retaining piece. Compared to the case where the biting portion that bites into the inner peripheral surface of the insertion tube portion is formed in a projecting manner, the manufacturing cost of the reinforcing cylinder having the biting portion is reduced. Can be achieved.
[0019]
The feature of the pipe joint structure according to claim 5 of the present invention is that, among the retaining pieces, at least the end of the retaining piece having a small projecting margin radially outward is inserted into the insertion tube portion. Therefore, an edge that is pressed against the inner peripheral surface of the insertion tube portion by the elastic restoring force thereof is formed.
[0020]
According to the above characteristic configuration, when the inner diameter of the insertion tube portion is offset toward the large diameter side of the tolerance range, the retaining function is mainly performed by the retaining piece having a large projecting margin in the radially outward direction. Even in this case, when the edge formed at the end of the retaining piece with a small protrusion is elastically pressed against the inner peripheral surface of the insertion tube, the insertion tube and the reinforcing cylinder Relative displacement resistance increases, and the displacement of the reinforcing cylinder due to vibration or impact during the assembly operation or the flow velocity of the transport fluid can be more effectively suppressed.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
FIGS. 1 to 11 show a state in which an insertion pipe portion 2 on one end side of a water pipe P made of polyethylene, which is an example of a fluid transport pipe made of synthetic resin, is sealed in a receiving pipe portion 1 of a joint body A made of cast iron. The pipe joint structure of the present invention for insertion connection is shown, and two annular grooves 1A and 1B having different groove widths in the tube axis X direction are formed on the inner peripheral surface 1a of the receiving pipe portion 1, In the first annular groove 1A having a small groove width located on the receiving side, a first elastic sealing material that seals between the inner peripheral surface 1a of the receiving pipe portion 1 and the outer peripheral surface 2a of the insertion pipe portion 2 is provided. 3 and a second annular groove 1B having a large groove width located on the back side, a retaining member that can bite into the outer peripheral surface 2a of the insertion pipe part 2 inserted and connected to the receiving pipe part 1 In an example, a synthetic resin (for example, polyacetal) or a metal (for example, polyacetal) formed in a substantially C-shape that can be elastically contracted in diameter A retaining ring 4 made of stainless steel or the like, and a second seal that seals between the inner peripheral surface 1a of the receiving tube portion 1 and the outer peripheral surface 2a of the insertion tube portion 2 at a position deeper than the retaining ring 4. An elastic sealing material 5 is attached.
[0022]
Of the inner peripheral surface 1a of the receiving tube portion 1, the peripheral surface located in the second annular groove 1B has the receiving tube portion 1 and the insertion tube as shown in FIGS. The retaining ring 4 is displaced to the reduced diameter side in accordance with the relative disengagement movement with the portion 2 in the tube axis X direction, that is, the retaining ring 4 is deformed to a reduced diameter against its elastic restoring force. A tapered cam surface 6 as a cam means is formed, and a region from the tip in the insertion tube portion 2 to at least a portion corresponding to the biting action portion of the retaining ring 4 or the vicinity thereof (the first embodiment) Then, in the insertion tube portion 2, a region slightly longer than the tube portion inserted into the receiving tube portion 1) inward in the radial direction of the insertion tube portion 2 due to the reduced diameter deformation of the retaining ring 4. A reinforcing cylinder 7 made of stainless steel (made of metal) that suppresses the deformation is internally fitted.
[0023]
Among the reinforcing cylinders 7, the outer diameter D1 of the inner fitting cylinder part 7A fitted into the insertion pipe part 2 is configured to be smaller than the inner diameter D2 of the insertion pipe part 2. Specifically, the insertion pipe part 2 The distal end portion 7d of the reinforcing cylinder 7 is formed in a tapered shape having a smaller diameter toward the distal end side.
Furthermore, the portion of the reinforcing cylinder 7 corresponding to the distal end portion of the insertion tube portion 2 at the time of internal fitting or the vicinity thereof (in this embodiment, the insertion tube is fitted in a predetermined position in the insertion tube portion 2). The proximal end portion 7e) corresponding to the distal end portion of the portion 2 is located so as to protrude outward in the radial direction from the inner peripheral surface 2c of the insertion tube portion 2, and as it is inserted into the insertion tube portion 2. A retaining portion 7B that is elastically deformed radially inward is formed, and a protrusion margin of the retaining portion 7B in the radially outward direction is varied in the circumferential direction.
[0024]
That is, as shown in FIGS. 2 and 3, the retaining portion 7B is a proximal end portion 7e of the reinforcing cylinder 7 and between adjacent V-shaped slits 7a formed at four locations in the circumferential direction. Is formed of a retaining piece 7b that is elastically deformed radially inwardly formed by bending a portion located radially outward, and the retaining piece 7b projects radially outward. It is composed of two types of protruding margins with different bills.
[0025]
Of the retaining pieces 7b, the circumferential width W1 of the retaining piece 7b having a large radial outward protrusion is smaller than the circumferential width W2 of the retaining piece 7b having a small radially outward protrusion. The retaining pieces 7b that are configured to have a small width and have a large radial outward projection allowance, and the retaining pieces 7b that have a small radial outward allowance each have a cylindrical axis (tube axis X). Those having a large protrusion allowance and those having a small protrusion allowance are alternately arranged in the circumferential direction so as to face each other in the radial direction passing through.
[0026]
Of the retaining pieces 7b, the retaining pieces 7b having the largest radial outward projection allowance are made to correspond to the maximum inner diameter within the dimensional tolerance range of the insertion tube portion 2 and radially outward. The retaining piece 7b having the smallest protrusion allowance is configured to correspond to the minimum inner diameter within the dimensional tolerance range of the insertion tube portion 2.
That is, as shown in FIGS. 4 to 7, when the inner diameter D <b> 2 of the insertion tube portion 2 is the maximum diameter within the dimensional tolerance range, a pair of protrusions outward in the radial direction is maximized. Only the retaining piece 7b is elastically deformed radially inward to retain and retain the reinforcing cylinder 7 fitted in a predetermined region in the insertion tube portion 2, and as shown in FIGS. When the inner diameter D2 of the insertion tube portion 2 is the minimum diameter within the dimensional tolerance range, all the retaining pieces 7b are elastically deformed radially inward, but mainly outward in the radial direction. The reinforcing cylinder 7 fitted in a predetermined region in the insertion tube portion 2 is retained by the pair of retaining pieces 7b having a minimum protrusion allowance.
[0027]
Further, of the retaining piece 7b, the end of the retaining piece 7b having a small radial outward protrusion is inserted into the insertion tube portion by its elastic restoring force as it is inserted into the insertion tube portion 2. An edge 7c is formed in pressure contact with the inner peripheral surface 2c.
In the case where the inner diameter D2 of the insertion tube portion 2 is offset toward the large diameter side of the tolerance range, the retaining piece 7b having a large radial outward protrusion is mainly used to exert the retaining function. However, even in this case, when the edge 7c formed at the end edge of the retaining piece 7b having a small protrusion is elastically pressed against the inner peripheral surface 2c of the insertion tube portion 2, the insertion tube portion 2 Relative displacement resistance in the tube axis X direction with respect to the reinforcing cylinder 7 increases, and the displacement of the reinforcing cylinder 7 due to vibration or impact during the assembling operation or the flow (flow velocity) of water (fluid) Can be more effectively suppressed.
[0028]
On the inner peripheral surface of the retaining ring 4, a number of biting protrusions 4 a that can bite into the outer peripheral surface 2 a of the insertion tube portion 2 are formed, and the outer peripheral surface 4 b of the retaining ring 4 is A tapered surface is formed along the cam surface 6.
Even when the tapered outer peripheral surface 4b of the retaining ring 4 and the cam surface 6 are not in contact with each other, the biting projection 4a thereof is caused by the elastic restoring force toward the reduced diameter side of the retaining ring 4. The insertion tube portion 2 is configured to slightly bite into the outer peripheral surface 2a. At the distal end portion of the insertion tube portion 2, the retaining ring 4 is elastically restored as the insertion tube portion 2 is inserted. A tapered second cam surface 2b is formed for diameter expansion deformation.
[0029]
The other end portion of the receiving pipe portion 1 of the joint body A is connected via a bolt 11 and a nut 12 to a flange portion 10 provided on a pipe fitting such as another pipe or a gate valve. The flange portion 13 is integrally formed.
[0030]
And in the state which fitted the internal fitting cylinder part 7A of the reinforcement cylinder 7 over the predetermined area | region in the said insertion pipe part 2, as shown in FIG.6 and FIG.10, the internal peripheral surface of the said insertion pipe part 2 Even if there is a gap between 2c and the outer peripheral surface of the inner fitting cylinder portion 7A of the reinforcing cylinder 7 fitted therein, as shown in FIGS. 7 and 11, it is caused by an external force due to an earthquake, unsettled settlement, or the like. When the receiving tube portion 1 and the insertion tube portion 2 move relative to each other, the retaining ring 4 is reduced in diameter by the taper surface 6 as the cam means, and the insertion tube portion 2 is moved radially inward accordingly. Since the inner peripheral surface 2c of the insertion tube portion 2 is pressed into contact with the outer peripheral surface of the inner fitting cylindrical portion 7A of the reinforcing cylindrical body 7, the subsequent deformation of the insertion tube portion 2 inward in the radial direction is performed after the diameter reduction. Can be suppressed.
[0031]
[Second Embodiment]
12 and 13, an insertion pipe part 2 of a polyethylene water pipe P, which is an example of a synthetic resin fluid transport pipe, is inserted and connected to the receiving pipe part 1 of the joint body A made of cast iron in a sealed state. Another embodiment of the pipe joint structure is shown, and the insertion tube portion 2 is made of synthetic rubber capable of sealing between the inner peripheral surface 1a of the receiving tube portion 1 and the outer peripheral surface 2a of the insertion tube portion 2 (for example, , Styrene butadiene rubber) and a cast iron push ring 21 that can be compressed to a sealed state (watertight state) by pressing the elastic seal 20 from the tube axis X direction. Fastening means 22 is provided to fasten and connect 21 and the receiving tube portion 1 from the tube axis X direction.
[0032]
Between the inner peripheral surface 21a of the push ring 21 and the outer peripheral surface 2a of the insertion tube portion 2, it is an example of a retaining member that can bite into the outer peripheral surface 2a of the insertion tube portion 2, and is elastic in the tube axis X direction. And a retaining ring 4 made of a synthetic resin (for example, polyacetal) or metal (for example, stainless steel) formed in a substantially C-shape that can be reduced in diameter, and an inner peripheral surface of the press ring 21 21a includes displacement of the retaining ring 4 toward the reduced diameter side in accordance with the relative proximity movement of the presser wheel 21 and the receiving tube portion 1 accompanying the tightening operation of the fastening means 22, that is, the retaining ring 4 is This is an example of cam means for reducing the diameter against the elastic restoring force, and a tapered cam surface 6 having a larger diameter toward the receiving tube portion 1 side is formed.
[0033]
Between the elastic seal material 20 and the press ring 21 and the retaining ring 4 facing each other in the tube axis X direction, only the elastic seal material 20 is pressed and compressed in the first half of the tightening operation by the fastening means 22. Sequential actuating means 23 for reducing the diameter of the retaining ring 4 against the elastic restoring force by the cam surface 6 in the tightening operation after the elastic sealing member 20 is in the set compression state. Is provided.
[0034]
Further, in the state where the retaining ring 4 slightly bites into the outer peripheral surface 2a of the insertion tube portion 2, an external force (tube axis core) in the detaching direction is applied to the insertion tube portion 1 and the insertion tube portion 2 that are inserted and connected. When the receiving tube portion 1 and the insertion tube portion 2 move relative to each other due to a tensile force in the X direction), the tapered outer peripheral surface 4b of the retaining ring 4 is pressed against the cam surface 6 accordingly. The diameter of the retaining ring 4 is reduced and the biting protrusion 4a of the retaining ring 4 is further bitten into the outer peripheral surface 2a of the insertion tube portion 2.
[0035]
And the area | region from the front-end | tip in the said insertion pipe part 2 to the site | part equivalent to at least the biting effect | action part of the retaining ring 4 or its vicinity (in the said 2nd Embodiment, the receiving pipe | tube among the said insertion pipe parts 2) (In the region slightly longer than the sum of the length of the tube portion inserted into the portion 1 and the length in the tube axis direction of the push ring 21), the radially inward of the insertion tube portion 2 due to the diameter reduction deformation of the retaining ring 4 A reinforcing cylinder 7 made of stainless steel (made of metal) that suppresses deformation to the inside is fitted.
[0036]
Among the reinforcing cylinders 7, the outer diameter D1 of the inner fitting cylinder part 7A fitted into the insertion pipe part 2 is configured to be smaller than the inner diameter D2 of the insertion pipe part 2. Specifically, the insertion pipe part 2 The distal end portion 7d of the reinforcing cylindrical body 7 is formed in a tapered shape having a smaller diameter toward the distal end side while being configured to be slightly smaller than the minimum inner diameter D2 within the dimensional tolerance range.
Furthermore, the portion of the reinforcing cylinder 7 corresponding to the distal end portion of the insertion tube portion 2 at the time of internal fitting or the vicinity thereof (in this embodiment, the insertion tube is fitted in a predetermined position in the insertion tube portion 2). The proximal end portion 7e) corresponding to the distal end portion of the portion 2 is positioned so as to protrude outward in the radial direction from the inner peripheral surface 2c of the insertion tube portion 2, and the diameter is increased as the tube is inserted into the insertion tube portion 2. A retaining portion 7B that is elastically deformed inward in the direction is formed, and a protrusion margin of the retaining portion 7B to the radially outer side is varied in the circumferential direction.
In other words, the retaining portion 7B is a base end portion of the reinforcing cylindrical body 7 and a portion located between adjacent V-shaped slits 7a formed at four locations in the circumferential direction is folded radially outward. The retaining piece 7b is formed by bending and can be elastically deformed radially inward, and the retaining piece 7b is composed of two kinds of protrusion allowances different in the radially outward protrusion allowance. ing.
[0037]
Of the retaining pieces 7b, the circumferential width W1 of the retaining piece 7b having a large radial outward protrusion is smaller than the circumferential width W2 of the retaining piece 7b having a small radially outward protrusion. Of the retaining piece 7b, the end of the retaining piece 7b, which has a small protrusion margin in the radial direction, is elastic at the end of insertion into the insertion tube portion 2. An edge 7c that is pressed against the inner peripheral surface 2c of the insertion tube portion 2 by a restoring force is formed.
[0038]
The sequential actuating means 23 moves the elastic seal material 20 from the direction of the tube axis X between the retaining ring 4 and the elastic seal material 20 as the push ring 21 and the receiving pipe portion 1 move relative to each other. Made of metal such as stainless steel or synthetic, provided with a first pressing surface 24a to be pressed and compressed, and a second pressing surface 24b capable of pressing the retaining ring 4 toward the cam surface 6 side of the press wheel 21 from the tube axis X direction. An annular intermediate pressing body 24 made of resin is provided, and the pressing wheel 21 and the receiving pipe portion 1 are disposed over a portion of the intermediate pressing body 24 and the inner peripheral surface of the pressing wheel 21 that are opposed or substantially opposed in the radial direction. Until the elastic sealing material 20 is in a set compression state with the relative proximity movement of the cam, the distance between the cam surface 6 of the press wheel 21 and the second pressing surface 24b of the intermediate pressing body 24 in the tube axis X direction. The retaining ring 4 that is not biting in does not elastically deform toward the reduced diameter side. When the elastic sealing material 20 is in a set compression state, the space is sheared between the outer peripheral surface of the intermediate pressing body 24 and the inner peripheral surface 21a of the press wheel 21 to release the interval restriction. That is, an interval regulating member (with a metal head such as a copper alloy or an aluminum alloy) that allows relative proximity movement between the cam surface 6 of the push wheel 21 and the second pressing surface 24b of the intermediate pressing body 24 in the tube axis X direction. Shear pin) 25 is provided.
[0039]
The fastening means 22 includes both bolt insertion holes that face each other in the direction of the tube axis X out of the bolt insertion holes 27 of the connection flange portion 26 of the receiving pipe portion 1 and the bolt insertion holes 29 of the connection protrusion 28 of the push ring 21. 27 and 29, and is composed of a T-shaped bolt 22A and a nut 22B.
[0040]
In addition, since the detail of the said reinforcement cylinder 7 and the retaining ring 4 is the same as 1st Embodiment, it attaches | subjects the same code | symbol to the same structure, and abbreviate | omits the description.
[0041]
[Third Embodiment]
In each of the above-described embodiments, the retaining portion 7B is a portion located between the proximal end portion of the reinforcing cylinder 7 and adjacent to the V-shaped slits 7a formed at four locations in the circumferential direction. Although it is configured from a retaining piece 7b that is elastically deformed radially inwardly formed by bending outward in the direction, as shown in FIG. A plurality of retaining pieces that can be elastically deformed radially inward by punching and forming a plurality of circumferential portions of the intermediate portion displaced in the center in the direction of the tube axis). The retaining portion 7B may be configured with 7b.
[0042]
[Fourth Embodiment]
In each of the above-described embodiments, the retaining portion 7B is composed of a retaining piece 7b that is elastically deformable radially inwardly formed by bending a plurality of circumferential portions of the reinforcing cylinder 7 radially outward. In addition, the outer peripheral surface of each retaining piece 7b is formed in an arc shape. However, as shown in FIG. 15, both circumferential edges of the retaining piece 7b along the slit 7a are radially outward. The second edge 7f may be bent and formed so as to protrude. According to this embodiment, as the internal fitting cylindrical portion 7A of the reinforcing cylindrical body 7 is internally fitted at a predetermined position in the insertion tube portion 2, it is bent at a plurality of locations in the circumferential direction of the reinforcing cylindrical body 7. The retaining piece 7b of the retaining portion 7B is pressed while being elastically deformed radially inward by contact with the inner peripheral surface 2c of the insertion tube portion 2, and at this time, the circumference of each retaining piece 7b is Since the second edges 7f formed on both side edges in the direction bite into the inner peripheral surface 2c of the insertion tube portion 2, it is caused by vibration or impact during the assembly operation or the flow (flow velocity) of the transport fluid. The displacement of the reinforcing cylinder 7 can be more effectively suppressed.
Moreover, since the second edge 7f of the retaining piece 7b protrudes radially outward by bending the retaining piece 7b, for example, on the outer peripheral surface of the retaining piece 7b, As the fitting tube portion 7A is fitted into a predetermined position in the insertion tube portion 2, the biting portion is compared with the case where the biting portion that is eaten into the inner peripheral surface 2c of the insertion tube portion 2 is formed to protrude. The manufacturing cost of the reinforcing cylinder 7 provided with can be reduced.
[0043]
[Other Embodiments]
(1) In each of the above-described embodiments, the joint main body A has been described with an example in which the connecting flange portion is integrally formed on the other end side in the tube axis direction of the receiving pipe portion 1. For example, it may be a joint body A provided with a pair of receiving pipe parts 1 into which the insertion pipe part 2 is inserted and connected separately. Moreover, the receiving pipe part currently formed in the connection port part side of pipe joint instruments, such as a gate valve, may be sufficient.
(2) In each of the above-described embodiments, the retaining portion 7B is composed of retaining pieces 7b formed by bending a plurality of circumferential locations of the reinforcing cylinder 7 radially outward. 7B may be composed of a retaining member made of an elastic material such as a spring material or synthetic rubber, and the retaining member may be fixed to the outer peripheral surface of the reinforcing cylinder 7.
(3) In each of the above-described embodiments, the inner fitting cylindrical portion 7A of the reinforcing cylindrical body 7 bites into the inner peripheral surface 2c of the insertion pipe portion 2 as it is fitted into a predetermined position in the insertion pipe portion 2. The biting portion is composed of radially outwardly protruding edges 7f formed on both circumferential edges of the protruding retaining piece 7b. The biting portion is formed to protrude on the outer peripheral surface of the retaining piece 7b. You may comprise from the protrusion processed.
(4) In each of the above-described embodiments, the reinforcing cylinder 7 that suppresses deformation in the radially inward direction of the insertion tube portion 2 due to the reduced diameter deformation of the retaining ring 4 is provided from the distal end in the insertion tube portion 2. Although the internal fitting was carried out over the wide area | region beyond the biting action location of the retaining ring 4, this reinforcement cylinder 7 is the biting action location of the retaining ring 4 at least from the front-end | tip in the insertion pipe part 2, or its vicinity. It suffices if it is fitted over the corresponding region or the region up to the vicinity thereof.
(5) In each of the above-described embodiments, the retaining piece 7b is configured with two types of projecting margins having different radially outward projecting margins, but three types having different projecting margins in the radially outward direction are different. You may comprise in the above protrusion margin.
Further, two or more types of retaining pieces 7b having different projecting allowances in the radially outward direction may be formed by being positioned in the tube axis X direction in a state of being located on the tip end side of the small projecting allowance. Good.
(6) In each of the above embodiments, the reinforcing cylinder 6 is manufactured from stainless steel, which is an example of a metal, but may be manufactured from a synthetic resin.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of a pipe joint structure according to the present invention.
FIG. 2 is a perspective view of a reinforcing cylinder.
FIG. 3 is a front view of a reinforcing cylinder.
FIG. 4 is a longitudinal sectional view showing an elastically deformed state in the middle of fitting between an insertion tube portion having a maximum inner diameter and a reinforcing cylinder.
FIG. 5 is a longitudinal sectional view showing an elastically deformed state at the time of completion of internal fitting between an insertion tube portion having a maximum inner diameter and a reinforcing cylinder.
FIG. 6 is an enlarged longitudinal sectional view of the main part of the pipe joint when the insertion pipe part is at the maximum inner diameter.
7 is an enlarged vertical cross-sectional view of the main part when the receiving pipe part and the insertion pipe part are moved relatively apart from the state of FIG.
FIG. 8 is a longitudinal sectional view showing an elastically deformed state in the middle of an internal fitting between an insertion tube portion having a minimum inner diameter and a reinforcing cylinder.
FIG. 9 is a longitudinal sectional view showing an elastically deformed state at the time of completion of internal fitting between an insertion tube portion having a minimum inner diameter and a reinforcing cylinder.
FIG. 10 is an enlarged longitudinal sectional view of the main part of the pipe joint when the insertion pipe part is at the minimum inner diameter.
11 is an enlarged longitudinal sectional view of the main part when the receiving pipe part and the insertion pipe part are moved relatively apart from the state of FIG.
FIG. 12 is a longitudinal sectional view showing a second embodiment of the pipe joint structure of the present invention.
FIG. 13 is an enlarged cross-sectional view of the main part during assembly.
FIG. 14 is a longitudinal sectional view of a reinforcing cylinder showing a third embodiment of the pipe joint structure of the present invention.
FIG. 15 is a partially cutaway front view of a reinforcing cylinder showing a fourth embodiment of the pipe joint structure of the present invention.
[Explanation of symbols]
1 Receptacle tube
1a Inner peripheral surface
2 Insertion tube
2a Outer peripheral surface
2c Inner peripheral surface
4 Retaining member (Retaining ring)
6 Cam means (tapered surface)
7 Reinforcing cylinder
7A Internal fitting cylinder
7B retaining part
7a slit
7b retaining piece
7c edge
21 Press wheel
21a Inner peripheral surface
X Tube core

Claims

受口管部に挿入接続された合成樹脂製の挿入管部の外周面と前記受口管部の内周面との間、又は、前記挿入管部に外装する状態で受口管部に管軸芯方向から固定連結される押輪の内周面と前記挿入管部の外周面との間に、挿入管部の外周面に喰い込み可能な抜止部材を設け、前記受口管部と挿入管部との相対離脱移動に連れて抜止部材を縮径側に変位させるカム手段を設けるとともに、前記挿入管部内の先端から少なくとも抜止部材の喰い込み作用箇所に相当する部位又はその近くまでの領域に補強筒体を内嵌してある管継手構造であって、前記挿入管部に内嵌される補強筒体の内嵌筒部の外径を、前記挿入管部の内径よりも小に構成するとともに、前記補強筒体のうち、内嵌時に挿入管部の先端部に対応する部位又はその近くには、挿入管部の内周面よりも径方向の外方に突出位置し、かつ、挿入管部内への挿入に連れて径方向内方に弾性変形する抜止め部を形成し、更に、前記抜止め部の径方向外方への突出代を周方向で異ならせてある管継手構造。A pipe is formed between the outer peripheral surface of the synthetic resin insertion tube portion inserted into and connected to the receiving tube portion and the inner peripheral surface of the receiving tube portion, or in a state where the outer tube is mounted on the insertion tube portion. A retaining member capable of biting into the outer peripheral surface of the insertion tube portion is provided between the inner peripheral surface of the press ring fixedly connected from the axial direction and the outer peripheral surface of the insertion tube portion, and the receiving tube portion and the insertion tube are provided. Cam means for displacing the retaining member to the reduced diameter side in accordance with the relative detachment movement with respect to the portion, and at least in a region corresponding to or near the portion where the retaining member bites into the insertion tube portion. A pipe joint structure in which a reinforcing cylinder is fitted, wherein the outer diameter of the inner fitting cylinder of the reinforcing cylinder fitted in the insertion pipe is smaller than the inner diameter of the insertion pipe. In addition, in the portion of the reinforcing cylinder that corresponds to the distal end portion of the insertion tube portion at the time of internal fitting, there is an insertion tube. A retaining portion that protrudes outward in the radial direction from the inner peripheral surface and elastically deforms radially inward as the tube is inserted into the insertion tube portion. The pipe joint structure with different projecting margins outward in the circumferential direction.

前記抜止め部が、補強筒体の周方向複数箇所を径方向外方に折曲げて形成された径方向内方に弾性変形可能な抜止め片から構成されているとともに、前記抜止め片が、径方向外方への突出代が異なる二種類以上の突出代に構成されている請求項１記載の管継手構造。The retaining portion is composed of a retaining piece that is elastically deformable radially inward formed by bending a plurality of circumferential locations of the reinforcing cylinder radially outward, and the retaining piece is The pipe joint structure according to claim 1, wherein two or more types of projecting allowances having different projecting allowances outward in the radial direction are configured.

前記抜止め片のうち、径方向外方への突出代が大きい抜止め片の周方向幅が、径方向外方への突出代が小さい抜止め片の周方向幅よりも小幅に構成されている請求項２記載の管継手構造。Among the retaining pieces, the circumferential width of the retaining piece having a large radial outward projection margin is configured to be smaller than the circumferential width of the retaining piece having a small radial outward projection margin. The pipe joint structure according to claim 2.

前記抜止め片の周方向両側縁が、径方向外方にエッジが突出する状態に折曲げ形成されている請求項２又は３記載の管継手構造。The pipe joint structure according to claim 2 or 3, wherein both side edges in the circumferential direction of the retaining piece are bent so that the edges protrude outward in the radial direction.

前記抜止め片のうち、少なくとも径方向外方への突出代が小さい抜止め片の端縁には、挿入管部内への挿入に連れてそれの弾性復元力で挿入管部の内周面に圧接されるエッジが形成されている請求項２〜４のいずれか１項に記載の管継手構造。Among the retaining pieces, at least an end edge of the retaining piece having a small radial outward protrusion is attached to the inner peripheral surface of the insertion tube portion by its elastic restoring force as it is inserted into the insertion tube portion. The pipe joint structure according to any one of claims 2 to 4, wherein an edge to be pressed is formed.