JP2004190700A

JP2004190700A - Structure of expansion joint

Info

Publication number: JP2004190700A
Application number: JP2002355770A
Authority: JP
Inventors: Hiroyuki Totsugi; 浩之戸次
Original assignee: Waterworks Technology Development Organization Co Ltd
Current assignee: Waterworks Technology Development Organization Co Ltd
Priority date: 2002-12-06
Filing date: 2002-12-06
Publication date: 2004-07-08
Anticipated expiration: 2022-12-06
Also published as: JP4293783B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide an expansion joint capable of effectively restricting heap of slurry and a flow loss, while securely and excellently achieving an expected extending/shrinking function and an expected bending function, and facilitating the work for assembling both pipes. <P>SOLUTION: A recessed part S formed over from the inner peripheral surface 1b of a receiver pipe part 1 and the inner peripheral surface 2a of an inserting pipe part 2 connected to the receiver pipe in the sealing condition freely to be extended/shrunken and freely to be bent and formed to be opened inward in the radial direction between the inserting side end surface 2b of the inserting pipe part 2 and the inner peripheral surface part 1d of the receiver pipe part 1 opposite to the described end surface 2b in the shaft core X direction of the pipes can be covered over the whole extension moving range of both the pipe parts 1 and 2. A synthetic resin sleeve 4 to be elastically deformed with bending of both the pipe bodies 1 and 2 in the condition that the cylindrical shape thereof is nearly maintained is inserted to be brought in contact with the inner peripheral surfaces of both the pipe parts 1 and 2, and at least one of the pipe parts 1 and 2 and the sleeve 4 can be slid with each other in the shaft core X direction of the pipes. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、受口管部に対して挿口管部が伸縮ならびに屈曲自在に密封状態で挿入接続されている伸縮管継手構造、或いは、継手管の管軸芯方向両側部に形成された受口管部の各々に、挿口管部が伸縮ならびに屈曲自在に密封状態で挿入接続されている伸縮管継手構造に関する。
【０００２】
【従来の技術】
この種の代表的な伸縮管継手構造としては、次の三つのタイプが存在する。
（イ）図１０に示す伸縮管継手構造では、受口管部１に対して挿口管部２が管軸芯Ｘ方向から伸縮ならびに一定角度範囲内で屈曲可能に挿入接続され、この受口管部１の内周面に形成された三つの周溝１ｃ〜１ｅのうち、受口側に位置する第１周溝１ｃには、受口管部１の大径側内周面１ａと挿口管部２の外周面２ｃとの間を密封する環状の弾性シール材３が装着されているとともに、管軸芯Ｘ方向の中央側に位置する第２周溝１ｄには、管軸芯Ｘ方向視において略Ｃの字状に形成された拡径側に弾性変形可能な抜止めリング８と、これの拡径変形を許容する状態で該抜止めリング８を受口管部１と同軸心状態に保持する弾性保持リング９が装着され、更に、挿口管部２の外周面の先端には、地震や不等沈下等に起因して両管部１，２が一定以上に相対離脱移動したとき、抜止めリング８に対して管軸芯Ｘ方向から接当してそれ以上の両管部１，２の相対離脱移動を阻止する円環状の抜止め突起２Ｂが一体形成されている。
【０００３】
また、挿口管部２の先端面２ｂが第３周溝１ｅの奥側の段差状内周面部分１ｇに接当する位置から抜止め突起２Ｂが抜止めリング８に接当する位置までの範囲が両管部１，２の伸縮範囲に構成されているとともに、挿口管部２と弾性シール材３及び抜止めリング８との接当箇所を支点として一定範囲内で屈曲自在に構成されている。
【０００４】
（ロ）図１１に示す伸縮管継手構造では、受口管部１に対して挿口管部２が管軸芯Ｘ方向から伸縮ならびに一定角度範囲内で屈曲可能に挿入接続され、この受口管部１の内周面に形成されたテーパー面１ｐと挿口管部２の外周面２ｃとの間には、これら両者１ｐ，２ｃ間を密封する環状の弾性シール材３が装着されているとともに、受口管部１の先端に形成されたフランジ部１Ａには、弾性シール材３を管軸芯Ｘ方向から圧縮状態に押圧可能な押輪５が、ボルト６・ナット７を介して締付け固定されている。
【０００５】
また、受口管部１の内周面に形成されて周溝１ｑには、管軸芯Ｘ方向視において略Ｃの字状に形成された縮径側に弾性変形可能な抜止めリング２０が、弾性シール材３の先端に設けられたバックアップリング２１に当接する状態で嵌着されているとともに、挿口管部２の外周面の先端には、地震や不等沈下等に起因して両管部１，２が一定以上に相対離脱移動したとき、抜止めリング２０に対して管軸芯Ｘ方向から接当してそれ以上の両管部１，２の相対離脱移動を阻止する円環状の抜止め突起２２が固着されている。
【０００６】
更に、挿口管部２の先端面２ｂが受口管部１の奥側の段差状内周面部分１ｇに接当する位置から抜止め突起２２が抜止めリング２０に接当する位置までの範囲が両管部１，２の伸縮範囲に構成されているとともに、挿口管部２と弾性シール材３及びバックアップリング２１との接当箇所を支点として一定範囲内で屈曲自在に構成されている。
【０００７】
（ハ）図１２に示す伸縮管継手構造では、継手管Ｐ３の管軸芯Ｘ方向両端部に形成された受口管部１の各々に、挿口管部２が伸縮ならびに一定角度範囲内で屈曲可能に挿入接続され、各受口管部１の内周面に形成された取付け溝１ｎには、管軸芯Ｘ方向視において略Ｃの字状に形成された拡径側に弾性変形可能な金属製の抜止めリング８と、これの拡径変形を許容する状態で該抜止めリング８を受口管部１と同軸心状態に保持する合成ゴム製の弾性保持リング９が装着され、更に、挿口管部２の外周面の先端には、地震や不等沈下等に起因して両管部１，２が一定以上に相対離脱移動したとき、抜止めリング８に対して管軸芯Ｘ方向から接当してそれ以上の両管部１，２の相対離脱移動を阻止する円環状の抜止め突起２Ｂが一体形成されている。
【０００８】
また、受口管部１の小径側内周面１ｋとこれに相対向する挿口管部２の外周面２ｃとの間を密封する環状の弾性シール材３が設けられ、更に、受口管部１の先端に形成されたフランジ部１Ａには、弾性シール材３を管軸芯Ｘ方向から圧縮状態に押圧可能な押輪５が、ボルト６・ナット７を介して連結されている。
【０００９】
更に、受口管部１の内周面に形成された中央周溝内で各挿口管部２の抜止め突起２Ｂが移動できる範囲が、両管部１，２の伸縮移動範囲に構成されているとともに、弾性シール材３及び抜止めリング８との接当箇所を支点として受口管部１と各挿口管部２とが一定範囲内で屈曲自在に構成されている（例えば、特許文献１参照。）。
【００１０】
【特許文献１】
特開平１１−６３３２８号公報（図１）
【特許文献２】
特開平７−１０３３７１号公報（図１）
【００１１】
【発明が解決しようとする課題】
前者の（イ）、（ロ）タイプでは、挿口管部２の挿入側先端面２ｂとこれに管軸芯Ｘ方向で相対向する受口管部１の奥側の段差状内周面部分１ｇとの間に、環状の窪み部Ｓが径方向内方の管内流路側に向かって開口形成され、また、後者の（ハ）タイプでは、継手管Ｐ３の内周面側で、かつ、両挿口管部２の挿入側先端面２ｂの対向面間に、環状の窪み部Ｓが径方向内方の管内流路側に向かって開口形成されている。
【００１２】
そのため、伸縮管継手構造としての所期の継手性能に影響を及ぼすものではないが、下水道の汚水配管に使用した場合では、管部の嵌合接続箇所において径方向内方に向かって開口形成される各窪み部Ｓに汚泥が堆積することを完全に回避することができず、また、上水道の浄水配管に使用した場合には、管部の嵌合接続箇所において径方向内方に向かって開口形成される窪み部Ｓで流動抵抗が増加し易い。
【００１３】
また、上述のような窪み部Ｓに起因する問題点を解決する方法として、前記受口管部の内周面と挿口管部の内周面とに亘って、受口側装着部と挿口側装着部とを互いに弾性的に屈曲自在に一体形成した屈曲部筒状弾性部材を設け、この筒状弾性部材の挿口側装着部の周方向複数箇所には、これの外面に埋設される挿口側当接部と、これから管外周側に起立されて挿口管部の先端と受口管部の奥側の段差状内周面部分との間に挾装されたとき、挿口側当接部及び筒状弾性部材の挿口側装着部を挿口管部の端部内面に沿わせるように揺動させる起立部を有する略Ｌ字形の剛性板が設けられているとともに、各剛性板の挿口側当接部の外周面に形成された周方向に沿う溝部に亘って、筒状弾性部材の挿口側装着部を一時的に先窄まり状に保持可能で、かつ、差込み接続される挿口管部の先端と当接する各剛性板の起立揺動に連れて切断される仮止め用線材を巻着したものが提案されている（例えば、特許文献２参照。）。
【００１４】
しかしながら、この提案されている伸縮管継手構造においては、差込み接続された両管部が地震や不等沈下等に起因して離脱移動したとき、挿口管部の先端とこれに管軸芯方向で相対向する受口管部の奥側の段差状内周面部分との間の間隙が拡大し、これに連れて各剛性板の起立部に対する起立姿勢への拘束力が解除されるため、筒状弾性部材の挿口側装着部の上側部分が剛性板の荷重で先窄まり状に変形し易く、従来と同様な問題を招来することになる。
【００１５】
本発明は、上述の実状に鑑みて為されたものであって、その主たる課題は、所期の伸縮機能及び屈曲機能を確実、良好に発揮させながらも、汚泥の堆積や流量損失を効果的に抑制することができるとともに、両管部の組付け作業も容易に行うことのできる伸縮管継手構造を提供する点にある。
【００１６】
【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、受口管部に対して挿口管部が伸縮ならびに屈曲自在に密封状態で挿入接続されている伸縮管継手構造であって、
前記受口管部の内周面と挿口管部の内周面とに亘って、挿口管部の挿入側先端面とこれに管軸芯方向で相対向する受口管部の内周面部分との間において径方向内方に向かって開口形成される窪み部を両管部の全伸縮移動範囲に亘って覆うことが可能で、かつ、両管体の屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂製のスリーブが、両管部の内周面に接触する状態で挿入装着されているとともに、両管部の少なくとも一方とスリーブとが管軸芯方向で相対摺動自在に構成されている点にある。
【００１７】
上記特徴構成によれば、両管部の内周面に亘って接触状態で挿入装着されたスリーブにより、両管部の全伸縮移動範囲に亘って、挿口管部の挿入側先端面とこれに管軸芯方向で相対向する受口管部の内周面部分との間において径方向内方に向かって開口形成される窪み部を覆うことができるから、汚泥の堆積や流量損失を抑制することができる。
【００１８】
しかも、両管部の少なくとも一方とスリーブとが管軸芯方向で相対摺動自在に構成されているため、地震や不等沈下等に起因する両管部の伸縮をスムースに行わせることができるとともに、スリーブが、両管部の屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂から製作されているから、スリーブの屈曲箇所における内周面を凹凸の少ない滑らかな状態に維持することができ、流動抵抗の低減化を図ることができる。
【００１９】
更に、受口管部に対して挿口管部を嵌合接続する場合、一方の管部にスリーブを予め取付けておくことにより、このスリーブが両管部の嵌合接続を案内するガイド部材として機能する。
【００２０】
従って、受口管部と挿口管部との所期の伸縮機能及び屈曲機能を確実、良好に発揮させながらも、従来構造に比して汚泥の堆積や流量損失を効果的に抑制することができるばかりでなく、そのためのスリーブを利用して両管部の嵌合接続作業も容易に行うことができる。
【００２１】
本発明の請求項２による特徴構成は、継手管の管軸芯方向両側部に形成された受口管部の各々に、挿口管部が伸縮ならびに屈曲自在に密封状態で挿入接続されている伸縮管継手構造であって、
両挿口管部の内周面に亘って、両挿口管部の挿入側先端面間において径方向内方に向かって開口形成される窪み部を両管部の全伸縮移動範囲に亘って覆うことが可能で、かつ、両管体の屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂製のスリーブが、両挿口管部の内周面に接触する状態で挿入装着されているとともに、両挿口管部の少なくとも一方とスリーブとが管軸芯方向で相対摺動自在に構成されている点にある。
【００２２】
上記特徴構成によれば、両挿口管部の内周面に亘って接触状態で挿入装着されたスリーブにより、両管部の全伸縮移動範囲に亘って、継手管の内周面側で、かつ、両挿口管部の挿入側先端面間において径方向内方に向かって開口形成される窪み部を覆うことができるから、汚泥の堆積や流量損失を抑制することができる。
【００２３】
しかも、両挿口管部の少なくとも一方とスリーブとが管軸芯方向で相対摺動自在に構成されているため、地震や不等沈下等に起因する各挿口管部と受口管部の伸縮をスムースに行わせることができるとともに、スリーブが、各挿口管部と受口管部管部との屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂から製作されているから、スリーブの屈曲箇所における内周面を凹凸の少ない滑らかな状態に維持することができ、流動抵抗の低減化を図ることができる。
【００２４】
更に、受口管部に対して両挿口管部を嵌合接続する場合、一方の管部にスリーブを予め取付けておくことにより、このスリーブが取付けられた一方の挿口管部を継手管の一方の受口管部に挿入接続したのち、他方の挿口管部を継手管の他方の受口管部に挿入接続する際、スリーブが両管部の嵌合接続を案内するガイド部材として機能する。
【００２５】
従って、受口管部と挿口管部との所期の伸縮機能及び屈曲機能を確実、良好に発揮させながらも、従来構造に比して汚泥の堆積や流量損失を効果的に抑制することができるばかりでなく、そのためのスリーブを利用して両管部の嵌合接続作業も容易に行うことができる。
【００２６】
本発明の請求項３による伸縮管継手構造の特徴構成は、前記スリーブと他方の管部との管軸芯方向での相対摺動を阻止する固定手段が設けられている点にある。
【００２７】
上記特徴構成によれば、両管部の嵌合接続や屈曲等に連れてスリーブの挿入装着位置がずれることがなく、所期の伸縮機能及び屈曲機能を発揮させながらも、長期間に亘って汚泥の堆積や流量損失を効果的に抑制することができる。
【００２８】
本発明の請求項４による伸縮管継手構造の特徴構成は、前記スリーブが、ポリエチレン樹脂で円筒状に成形されているとともに、それの厚みが１．５ｍｍ〜４．０ｍｍまでの範囲、好ましくは、２．０ｍｍ〜３．０ｍｍの範囲に構成されている点にある。
【００２９】
上記特徴構成によれば、ポリエチレン樹脂製のスリーブの厚みが１．５ｍｍ以上であれば、両管部の屈曲に伴うスリーブの径方向内方への屈曲変形を少なくすることができ、また、スリーブの厚みが４．０ｍｍ以下であれば、両管部の屈曲に支障を与えることが無い。
【００３０】
更に、ポリエチレン樹脂製のスリーブの厚みが２．０ｍｍ以上であれば、両管部の屈曲に伴うスリーブの径方向内方への屈曲変形を効果的に抑制することができ、また、スリーブの厚みが３．０ｍｍ以下であれば、両管部の屈曲をスムースに行わせることができる。
【００３１】
従って、両管部の屈曲に追従して、スリーブがそれの円筒形状を略維持したまま弾性変形するから、流路面積が大きく減少することがなく、流動抵抗の軽減化を図ることができる。
【００３２】
本発明の請求項５による伸縮管継手構造の特徴構成は、前記スリーブの内周面の挿入側先端部が、先端側ほど大径となるテーパー面に形成されている点にある。
【００３３】
上記特徴構成によれば、スリーブの挿入側先端部と管部の内周面との間での段差が滑らかになり、汚泥の堆積や流量損失を効果的に抑制することができる。
【００３４】
【発明の実施の形態】
〔第１実施形態〕
図１〜図４は、流体管の一例である水道管の配管系に設けられる伸縮管継手構造を示し、直管状の鋳鉄製の水道管Ｐ１の一端側に形成された受口管部１に、直管状の鋳鉄製の水道管Ｐ２の一端部に形成された挿口管部２が伸縮ならびに屈曲可能な状態で管軸芯Ｘ方向から挿入接続され、受口管部１の大径側内周面１ａに形成された三つの周溝１ｃ〜１ｅのうち、受口側に位置する第１周溝１ｃには、受口管部１の大径側内周面１ａと挿口管部２の外周面２ｃとの間を密封するための合成ゴム製の弾性シール材３が装着されているとともに、管軸芯Ｘ方向の中央側に位置する第２周溝１ｄには、管軸芯Ｘ方向視において略Ｃの字状に形成された拡径側に弾性変形可能な金属製の抜止めリング８と、これの拡径変形を許容する状態で該抜止めリング８を受口管部１と同軸心状態に保持する合成ゴム製の弾性保持リング９が装着され、更に、挿口管部２の外周面の先端には、地震や不等沈下等に起因して両管部１，２が一定以上に相対離脱移動したとき、抜止めリング８に対して管軸芯Ｘ方向から接当してそれ以上の両管部１，２の相対離脱移動を阻止する円環状の抜止め突起２Ｂが一体形成されている。
【００３５】
前記挿口管部２の先端面２ｂが受口管部１の奥側の段差状内周面部分１ｇに接当する位置から抜止め突起２Ｂが抜止めリング８に接当する位置までの範囲が、両管部１，２の管軸芯Ｘ方向での伸縮移動範囲に構成されているとともに、前記受口管部１と挿口管部２との嵌合接続部には、両管部１，２の設定角度範囲内での屈曲を許容する融通Ａが設けられている。
【００３６】
この融通Ａは、受口管部１の受口端部の内周面を、挿口管部２の抜止め突起２Ｂの外径よりも少し大径で、かつ、外方側ほど大径となるテーパー面１ｆに形成するとともに、受口管部１の大径側内周面１ａのうち、第３周溝１ｅの底面の内径を、挿口管部２の抜止め突起２Ｂの外径よりも少し大径に形成して、受口管部１の大径側内周面１ａと挿口管部２の外周面２ｃとの間で、かつ、弾性シール材３の管軸芯Ｘ方向の外側脇及び抜止めリング８の管軸芯Ｘ方向の奥側脇に、弾性シール材３を略支点とする両管部１，２の屈曲を許容する空隙Ｓ１，Ｓ２を形成することにより構成されている。
【００３７】
そして、前記受口管部１に施された防蝕用ライニング層１Ｄの小径側内周面１ｂと、これに管軸芯Ｘ方向から密封状態で挿入接続される挿口管部２に施された防蝕用ライニング層２Ａの内周面２ａとに亘って、挿口管部２の挿入側先端面２ｂとこれに管軸芯Ｘ方向で相対向する受口管部１の段差状内周面部分１ｇとの間において径方向内方に向かって開口形成される窪み部Ｓを両管部１，２の全伸縮移動範囲に亘って覆う長さを有し、かつ、両管部１，２の屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂製のスリーブ４が、両管部１，２の内周面１ｂ，２ａの全周に亘って密着する状態で挿入装着されているとともに、両管部１，２とスリーブ４とが管軸芯方向で相対摺動自在に構成されている。
【００３８】
前記スリーブ４は、受口管部１の全長よりも少し大なる長さに構成されているとともに、それの外周面の管軸芯Ｘ方向中央位置には、窪み部Ｓに入り込む環状の係止部４Ａが一体的に突出形成されていて、受口管部１に対して挿口管部２を嵌合接続する際、スリーブ４に突設された係止部４Ａが、窪み部Ｓを構成する挿口管部２の挿入側先端面２ｂとこれに管軸芯Ｘ方向で相対向する受口管部１の段差状内周面部分１ｇとのうちの少なくとも一方に接当して、両管部１，２に対するスリーブ４の所定装着領域からの抜け出し移動を規制するように構成されている。
【００３９】
更に、前記スリーブ４は、高密度ポリエチレン（ＨＤＰＥ）や高性能ポリエチレン（ＨＰＰＥ）等のポリエチレン樹脂で円筒状に成形されているとともに、それの厚みが１．５ｍｍ〜４．０ｍｍまでの範囲、好ましくは、２．０ｍｍ〜３．０ｍｍの範囲に構成され、更に、スリーブ４の内周面の挿入先端部が、先端側ほど大径となるテーパー面４ａに形成されている。
【００４０】
尚、前記スリーブ４のうち、挿口管部２に挿入装着される嵌合筒部分の外径を、挿口管部２の内周面２ａの内径よりも僅かに大に構成して、この嵌合筒部分を挿口管部２に圧入することにより、スリーブ４と挿口管部２との管軸芯Ｘ方向での相対移動を阻止するように構成してもよい。
【００４１】
そして、両管部１，２の内周面に亘って密着状態で挿入装着されたポリエチレン樹脂製のスリーブ４により、図１、図４に示すように、両管部１，２の嵌合接続箇所において径方向内方に向かって開口形成される窪み部Ｓを確実に覆うことができるから、汚泥の堆積や乱流による流量損失を抑制することができる。
【００４２】
しかも、両管部１，２の少なくとも一方とスリーブ４とが管軸芯Ｘ方向で相対摺動自在に構成されているため、地震や不等沈下等に起因する両管部１，２の伸縮作動をスムースに行わせることができるとともに、スリーブ４が、両管部１，２の屈曲に追従して円筒形状を略維持したまま弾性変形するポリエチレン樹脂から製作されていて、スリーブ４の屈曲箇所における内周面を凹凸の少ない滑らかな状態に維持することができるから、流路面積が大きく減少することがなく、流動抵抗の低減化を図ることができる。
【００４３】
〔第２実施形態〕
図５、図６は、流体管の一例である水道管の配管系に設けられる別の伸縮管継手構造を示し、鋳鉄製の継手管Ｐ３の一端側に形成された受口管部１に、直管状の鋳鉄製の水道管Ｐ２の一端部に形成された挿口管部２が伸縮ならびに屈曲可能な状態で管軸芯Ｘ方向から挿入接続され、受口管部１の大径側内周面１ａのうち、開口側ほど大径となる状態で形成されたテーパー面１ｈと挿口管部２の外周面２ｃとの間には、これら両者１ｈ，２ｃ間を密封するための合成ゴム製の弾性シール材３が装着されているとともに、受口管部１の先端に形成されたフランジ部１Ａには、弾性シール材３を管軸芯Ｘ方向から圧縮状態に押圧可能な押輪５が、ボルト６・ナット７を介して管軸芯Ｘ方向から締め付け固定されている。
【００４４】
前記押輪５の内周面に形成した周溝５ａには、拡径側に弾性変形可能な状態で挿口管部２の外周面２ｃに食い込む管軸芯Ｘ方向略Ｃの字状の金属製のロックリング１１が配設されているとともに、前記周溝５ａの底面が、両管部１，２の管軸芯Ｘ方向に沿った一定範囲内での伸縮移動を許容する平行摺接ガイド面と、両管部１，２が一定以上に離脱移動したとき、その離脱移動に連れてロックリング１１を径方向内方に向かって食い込み移動させるテーパー摺接ガイド面とから構成されている。
【００４５】
前記受口管部１の奥側の段差状内周面部分１ｇから弾性シール材３までの範囲が、両管部１，２の差込み接続時における管軸芯Ｘ方向での伸縮調整範囲に構成されているとともに、前記受口管部１と挿口管部２との嵌合接続部には、両管部１，２の設定角度範囲内での屈曲を許容する融通Ａが設けられている。
【００４６】
前記融通Ａは、受口管部１の大径側内周面１ａのうち、テーパー面１ｈと段差状内周面部分１ｇとの間に位置する内周面部分１ｊを、テーパー面１ｈの傾斜方向とは逆に、段差状内周面部分１ｇ側ほど大径となるテーパー面に形成するとともに、押輪５の管軸芯Ｘ方向両端部における内周面５ｂを、挿口管部２の外周面２ｃの外径よりも少し大径に形成することにより、受口管部１の大径側内周面１ａと挿口管部２の外周面２ｃとの間で、かつ、ロックリング１１の管軸芯Ｘ方向の外側脇及び弾性シール材３の管軸芯Ｘ方向の奥側脇に、弾性シール材３を略支点とする両管部１，２の屈曲を許容する空隙Ｓ１，Ｓ２を形成することにより構成されている。
【００４７】
そして、前記受口管部１の小径側内周面１ｂと挿口管部２の内周面２ａとに亘って、挿口管部２の挿入側先端面２ｂとこれに管軸芯Ｘ方向で相対向する受口管部１の段差状内周面部分１ｇとの間において径方向内方に向かって開口形成される窪み部Ｓを両管部１，２の全伸縮移動範囲に亘って覆う長さを有し、かつ、両管部１，２の屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂製のスリーブ４が、両管部１，２の内周面１ｂ，の全周に亘って密着する状態で挿入装着されているとともに、両管部１，２とスリーブ４とが管軸芯Ｘ方向で相対摺動自在に構成されている。
【００４８】
尚、前記スリーブ４のうち、挿口管部２に挿入装着される嵌合筒部分の外径を、挿口管部２の内周面２ａの内径よりも僅かに大に構成して、この嵌合筒部分を挿口管部２に圧入することにより、スリーブ４と挿口管部２との管軸芯Ｘ方向での相対移動を阻止するように構成してもよい。
【００４９】
更に、前記スリーブ４は、高密度ポリエチレン（ＨＤＰＥ）や高性能ポリエチレン（ＨＰＰＥ）等のポリエチレン樹脂で円筒状に成形されているとともに、それの厚みが１．５ｍｍ〜４．０ｍｍまでの範囲、好ましくは、２．０ｍｍ〜３．０ｍｍの範囲に構成され、更に、スリーブ４の内周面の挿入先端部が、先端側ほど大径となるテーパー面４ａに形成されている。
【００５０】
尚、その他の構成は、第１実施形態で説明した構成と同一であるから、同一の構成箇所には、第１実施形態と同一の番号を付記してそれの説明は省略する。
【００５１】
〔第３実施形態〕
図７、図８は、流体管の一例である水道管の配管系に設けられる別の伸縮管継手構造を示し、鋳鉄製の継手管Ｐ３の管軸芯Ｘ方向両端部に形成された受口管部１の各々に、直管状の鋳鉄製の水道管Ｐ２の一端部に形成された挿口管部２が、伸縮ならびに屈曲可能な状態で管軸芯Ｘ方向に沿って摺動自在に挿入接続され、各受口管部１と挿口管部２との間には、両管部１，２が管軸芯Ｘ方向に沿って一定以上に相対離脱移動したとき、管軸芯Ｘ方向から互いに接当してそれ以上の離脱移動を阻止する離脱防止手段Ｃが設けられている。
【００５２】
また、受口管部１の小径側内周面１ｋのうち、開口側ほど大径となる状態で形成されたテーパー面１ｍと挿口管部２の外周面２ｃとの間には、これら両者１ｍ，２ｃ間を密封するための合成ゴム製の弾性シール材３が装着されているとともに、前記受口管部１と挿口管部２との嵌合接続部には、両管部１，２の設定角度範囲内での屈曲を許容する融通Ａが設けられ、更に、受口管部１の先端に形成されたフランジ部１Ａには、弾性シール材３を管軸芯Ｘ方向から圧縮状態に押圧可能な押輪５が、ボルト６・ナット７を介して締付け固定されている。
【００５３】
前記離脱防止手段Ｃを構成するに、受口管部１の内周面に形成された円環状の取付け溝１ｎに、管軸芯Ｘ方向視において略Ｃの字状に形成された拡径側に弾性変形可能な金属製の抜止めリング８と、これの拡径変形を許容する状態で該抜止めリング８を受口管部１と同軸心状態に保持する合成ゴム製の弾性保持リング９とを装着するとともに、挿口管部２の外周面２ｃの先端部には、地震や不等沈下等に起因して両管部１，２が一定以上に相対離脱移動したとき、抜止めリング８に対して管軸芯Ｘ方向から接当してそれ以上の両管部１，２の相対離脱移動を阻止する円環状の抜止め突起２Ｂが一体形成されている。
【００５４】
前記融通Ａは、受口管部１の小径側内周面１ｋを、挿口管部２の外周面２ｃの外径よりも大径に構成するとともに、押輪５の内周面５ｃを、挿口管部２の外周面２ｃの外径よりも大径で、かつ、受口管部１から管軸芯Ｘ方向に離れるほど大径となるテーパー面に形成して、受口管部１の小径側内周面１ｋと挿口管部２の外周面２ｃとの間で、かつ、弾性シール材３の管軸芯Ｘ方向の外側脇及びに抜止めリング８の管軸芯Ｘ方向の奥側脇に、弾性シール材３を略支点とする両管部１，２の屈曲を許容する空隙Ｓ１，Ｓ２を形成することにより構成されている。
【００５５】
そして、前記継手管Ｐ３の両受口管部１に対して管軸芯Ｘ方向から密封状態で挿入接続された両挿口管部２の内周面２ａに亘って、継手管Ｐ３の内周面側で、かつ、両挿口管部２の挿入側先端面２ｂ間において径方向内方に向かって開口形成される窪み部Ｓを覆う長さを有し、かつ、両管部１，２の屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂製のスリーブ４が、両挿口管部２の内周面２ａの全周に亘って密着する状態で挿入装着されているとともに、両管部１，２とスリーブ４とが管軸芯方向で相対摺動自在に構成されている。
【００５６】
尚、前記スリーブ４のうち、一方の挿口管部２に挿入装着される嵌合筒部分の外径を、挿口管部２の内周面２ａの内径よりも僅かに大に構成して、この嵌合筒部分を挿口管部２に圧入することにより、スリーブ４と一方の挿口管部２との管軸芯Ｘ方向での相対移動を阻止するように構成してもよい。
【００５７】
前記スリーブ４の外周面の管軸芯Ｘ方向の一端側に偏位した部位には、窪み部Ｓに入り込む環状の係止部４Ａが一体的に突出形成されていて、受口管部１に対して挿口管部２を嵌合接続する際、スリーブ４に突設された係止部４Ａが、窪み部Ｓを構成する両挿口管部２の挿入側先端面２ｂの一方に接当して、両管部１，２に対するスリーブ４の所定装着領域からの抜け出し移動を規制するように構成されている。
【００５８】
更に、前記スリーブ４は、高密度ポリエチレン（ＨＤＰＥ）や高性能ポリエチレン（ＨＰＰＥ）等のポリエチレン樹脂で円筒状に成形されているとともに、それの厚みが１．５ｍｍ〜４．０ｍｍまでの範囲、好ましくは、２．０ｍｍ〜３．０ｍｍの範囲に構成され、更に、スリーブ４の内周面の挿入先端部が、先端側ほど大径となるテーパー面４ａに形成されている。
【００５９】
〔その他の実施形態〕
（１）上述の第１〜第３実施形態において、スリーブ４を、挿口管部２に圧入固定することにより、挿口管部２に対するスリーブ４の管軸芯Ｘ方向での相対移動を阻止する固定方法を説明したが、図９に示すように、スリーブ４の周方向複数箇所を受口管部１又は挿口管部２にボルト１０で締付け固定してもよい。
この場合、ボルト１０で締付け固定されるスリーブ４の取付け部４Ｂを、他の部位よりも厚肉に構成するとよい。
更に、固定方法としては、上述の圧入方法やボルトによる締付け固定方法以外に、接着剤等による他の固定方法を採用してもよい。
（２）上述の各実施形態では、両管部１，２の内周面に亘って挿入装着されるスリーブ４を単体から構成したが、このスリーブ４を管軸芯Ｘ方向で二分割して、各分割スリーブ体の一端部側を管体１，２の内周面に管軸芯方向での相対移動を阻止した状態で取付けるとともに、両分割スリーブ体の他端部側同士を、両管体１，２の屈曲に追従して円筒形状を略維持したまま弾性変形する状態で、かつ、密着状態で嵌合接合してもよい。
（３）上述の各実施形態では、両管部１，２の内周面のうち、スリーブ４が挿入装着される箇所の内径を同一径に構成してある場合について説明したが、両管体１，２の内周面のスリーブ装着箇所の内径が異なる場合には、それに対応してスリーブ２の外径も変更することになる。
【図面の簡単な説明】
【図１】本発明の第１実施形態を示す伸縮管継手構造の断面側面図
【図２】図１におけるＩＩ−ＩＩ線断面図
【図３】受口管部に挿口管部を挿入接続するときの断面側面図
【図４】屈曲状態を示す断面側面図
【図５】本発明の第２実施形態を示す伸縮管継手構造の断面側面図
【図６】屈曲状態を示す断面側面図
【図７】本発明の第３実施形態を示す伸縮管継手構造の断面側面図
【図８】屈曲状態を示す断面側面図
【図９】本発明の第４実施形態を示す伸縮管継手構造の要部の拡大断面側面図
【図１０】従来の伸縮管継手構造を示す断面側面図
【図１１】他の従来の伸縮管継手構造を示す断面側面図
【図１２】他の従来の伸縮管継手構造を示す断面側面図
【符号の説明】
Ａ融通
Ｐ１水道管
Ｐ２水道管
Ｐ３継手管
Ｓ窪み部
Ｘ管軸芯
１受口管部
１ａ内周面（大径側内周面）
１ｂ内周面（小径側内周面）
２挿口管部
２ａ内周面
２ｂ挿入側先端面
２ｃ外周面
４スリーブ
４Ａ係止部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a telescopic pipe joint structure in which an insertion pipe part is inserted and connected to a reception pipe part in a sealed state so as to expand and contract and bend freely, or a receiving pipe formed on both sides of a joint pipe in a pipe axis direction. The present invention relates to a telescopic pipe joint structure in which an insertion pipe part is inserted and connected to each of the mouth pipe parts in a sealed state so as to expand and contract and bend freely.
[0002]
[Prior art]
The following three types exist as typical expansion pipe joint structures of this kind.
(A) In the telescopic joint structure shown in FIG. 10, the insertion pipe part 2 is inserted and connected to the reception pipe part 1 so as to expand and contract from the pipe axis X direction and bend within a certain angle range. Of the three peripheral grooves 1c to 1e formed on the inner peripheral surface of the tube portion 1, the large-diameter inner peripheral surface 1a of the receiving tube portion 1 is inserted into the first peripheral groove 1c located on the receiving side. An annular elastic sealing member 3 for sealing between the outer peripheral surface 2c of the mouth tube portion 2 is mounted, and a second peripheral groove 1d located at the center side in the tube axis X direction has a tube axis X A retaining ring 8, which is formed in a substantially C-shape when viewed from the direction and which can be elastically deformed to the enlarged diameter side, and the retaining ring 8 is coaxial with the receiving tube portion 1 in a state where the increased diameter deformation is permitted. An elastic retaining ring 9 for maintaining the state is attached, and further, both the pipe portions 1 and 2 are fixed at the tip of the outer peripheral surface of the insertion tube portion 2 due to an earthquake, uneven settlement, or the like. When it is relatively displaced upward, an annular retaining projection 2B that comes into contact with the retaining ring 8 from the tube axis X direction and prevents further relative disengagement movement of the two tube portions 1 and 2 is integrated. Is formed.
[0003]
Further, from the position where the distal end surface 2b of the insertion tube portion 2 contacts the stepped inner peripheral surface portion 1g on the back side of the third peripheral groove 1e to the position where the retaining projection 2B contacts the retaining ring 8. The range is configured to be the expansion and contraction range of the two pipe portions 1 and 2, and is configured to be bent within a certain range with the contact point between the insertion pipe portion 2 and the elastic sealing material 3 and the retaining ring 8 as a fulcrum. ing.
[0004]
(B) In the expandable pipe joint structure shown in FIG. 11, the insertion pipe section 2 is inserted and connected to the reception pipe section 1 so as to be able to expand and contract from the pipe axis X direction and bend within a certain angle range. Between the tapered surface 1p formed on the inner peripheral surface of the tube portion 1 and the outer peripheral surface 2c of the insertion tube portion 2, an annular elastic sealing material 3 for sealing between these two portions 1p and 2c is mounted. At the same time, a pressing ring 5 capable of pressing the elastic sealing material 3 in a compressed state from the pipe axis X direction is tightened and fixed to the flange portion 1A formed at the tip of the receiving pipe portion 1 via bolts 6 and nuts 7. Have been.
[0005]
In the circumferential groove 1q formed on the inner peripheral surface of the receiving tube portion 1, a retaining ring 20, which is formed in a substantially C-shape when viewed in the tube axis X direction and is elastically deformable to a reduced diameter side, is provided. Are fitted in contact with the backup ring 21 provided at the tip of the elastic sealing material 3, and are attached to the tip of the outer peripheral surface of the insertion tube portion 2 due to an earthquake, uneven settlement, or the like. When the tube portions 1 and 2 move relative to each other more than a certain distance, the annular shape prevents the tube portions 1 and 2 from coming into contact with the retaining ring 20 from the tube axis X direction to prevent further relative movement. Are secured.
[0006]
Further, from the position where the distal end surface 2b of the insertion tube portion 2 contacts the stepped inner peripheral surface portion 1g on the back side of the reception tube portion 1 to the position where the retaining projection 22 contacts the retaining ring 20. The range is configured to be the expansion and contraction range of the two pipe portions 1 and 2, and is configured to be bendable within a certain range with a contact point between the insertion pipe portion 2 and the elastic sealing material 3 and the backup ring 21 as a fulcrum. I have.
[0007]
(C) In the telescopic pipe joint structure shown in FIG. 12, the insertion pipe part 2 expands and contracts in each of the receiving pipe parts 1 formed at both ends of the joint pipe P3 in the pipe axis X direction within a certain angle range. The mounting groove 1n formed in the inner peripheral surface of each receiving tube portion 1 is inserted and connected so as to be bendable, and can be elastically deformed to an enlarged diameter side formed in a substantially C shape when viewed in the tube axis X direction. A metal retaining ring 8 and an elastic retaining ring 9 made of synthetic rubber for holding the retaining ring 8 coaxially with the receiving tube portion 1 in a state where the retaining ring 8 is allowed to expand and deform. Further, when the two pipe parts 1 and 2 are displaced relative to each other by a certain amount or more due to an earthquake, unequal settlement, or the like, a pipe shaft is formed at the tip of the outer peripheral surface of the insertion pipe part 2. An annular retaining projection 2B is integrally formed to contact the core X direction and prevent the relative detachment movement of the two tube portions 1 and 2 any further. .
[0008]
In addition, an annular elastic sealing material 3 is provided for sealing between the small-diameter-side inner peripheral surface 1k of the receiving tube portion 1 and the outer peripheral surface 2c of the insertion tube portion 2 opposed thereto. A pressing ring 5 capable of pressing the elastic sealing material 3 in a compressed state from the tube axis X direction is connected to a flange portion 1A formed at the tip of the portion 1 via bolts 6 and nuts 7.
[0009]
Furthermore, the range in which the retaining projection 2B of each insertion tube portion 2 can move within the central circumferential groove formed on the inner peripheral surface of the receiving tube portion 1 is configured as the expansion and contraction movement range of the two tube portions 1 and 2. In addition, the receiving tube portion 1 and each of the insertion tube portions 2 are configured to be able to bend within a certain range with a contact point between the elastic sealing material 3 and the retaining ring 8 as a fulcrum (for example, see Patents). Reference 1).
[0010]
[Patent Document 1]
JP-A-11-63328 (FIG. 1)
[Patent Document 2]
JP-A-7-103371 (FIG. 1)
[0011]
[Problems to be solved by the invention]
In the former (a) and (b) types, the stepped inner peripheral surface portion on the insertion side distal end surface 2b of the insertion tube portion 2 and the depth side of the reception tube portion 1 opposed to this in the tube axis X direction. 1g, an annular recessed portion S is formed to open toward the pipe flow path inward in the radial direction, and in the latter (c) type, on the inner peripheral surface side of the joint pipe P3, An annular recessed portion S is formed between the opposing surfaces of the insertion-side tip surface 2b of the insertion tube portion 2 toward the in-pipe flow path side inward in the radial direction.
[0012]
Therefore, it does not affect the expected joint performance of the expansion joint structure.However, when used for sewage pipes of sewers, openings are formed radially inward at fitting points of pipes. It is not possible to completely prevent sludge from accumulating in each of the depressions S, and when used for water purification pipes for water supply, the pipes are opened radially inward at the fitting connection points of the pipes. The flow resistance tends to increase at the formed depression S.
[0013]
Further, as a method for solving the above-mentioned problem caused by the recessed portion S, the receiving side mounting portion is inserted between the inner peripheral surface of the receiving tube portion and the inner peripheral surface of the insertion tube portion. A bent portion cylindrical elastic member integrally formed so as to be elastically bendable with the mouth-side mounting portion is provided, and a plurality of circumferential positions of the insertion-side mounting portion of the cylindrical elastic member are embedded in the outer surface thereof. The insertion-side abutting part, which is erected from the outer circumference of the pipe, is inserted between the tip of the insertion pipe and the stepped inner peripheral part on the back side of the receiving pipe. A substantially L-shaped rigid plate having an upright portion for swinging the side contact portion and the insertion side mounting portion of the tubular elastic member along the inner surface of the end portion of the insertion tube portion is provided, and It is possible to temporarily hold the insertion-side mounting portion of the cylindrical elastic member in a tapered shape over a circumferential groove formed on the outer peripheral surface of the insertion-side contact portion of the rigid plate. In addition, there is a proposal in which a wire for temporary fixing is wound around the rigid plate that comes into contact with the distal end of the insertion tube portion to be inserted and connected, as the standing plate is rocked (for example, see Patent Document 2). ).
[0014]
However, in this proposed expansion joint structure, when both of the plugged and connected pipe parts are displaced due to an earthquake, uneven settlement, etc., the tip of the insertion pipe section and the pipe axis direction Since the gap between the stepped inner peripheral surface portion on the back side of the receiving pipe portion facing each other is enlarged, and the restraining force of each rigid plate to the upright position with respect to the upright portion is released, The upper portion of the insertion portion on the insertion side of the tubular elastic member is easily deformed into a tapered shape due to the load of the rigid plate, causing the same problem as in the related art.
[0015]
The present invention has been made in view of the above situation, and its main problem is to reliably and satisfactorily exhibit the desired expansion and contraction function and bending function, while effectively preventing sludge accumulation and flow loss. Another object of the present invention is to provide a telescopic pipe joint structure that can suppress the number of pipes and can easily perform an assembling operation of both pipe parts.
[0016]
[Means for Solving the Problems]
A characteristic configuration according to claim 1 of the present invention is a telescopic joint structure in which an insertion tube part is inserted and connected in a sealed state so as to expand and contract and bend freely with respect to a reception tube part,
Over the inner peripheral surface of the receiving tube portion and the inner peripheral surface of the receiving tube portion, the insertion-side distal end surface of the receiving tube portion and the inner periphery of the receiving tube portion opposed to the front surface in the tube axis direction. It is possible to cover the depression formed in the radially inward between the surface portions over the entire range of expansion and contraction movement of the two tube portions, and to follow the bending of the two tube bodies and to form a cylindrical shape The sleeve is made of synthetic resin that is elastically deformed while maintaining substantially the same, and is inserted and mounted so as to be in contact with the inner peripheral surfaces of the two pipe parts, and at least one of the two pipe parts and the sleeve are opposed in the pipe axis direction. The point is that it is configured to be slidable.
[0017]
According to the above-mentioned characteristic configuration, the insertion-side tip surface of the insertion tube portion and the insertion-side tip surface of the insertion tube portion over the entire expansion and contraction movement range of the both tube portions by the sleeve inserted and mounted in contact with the inner peripheral surfaces of both tube portions. The cavities that are formed radially inward can be covered between the inner peripheral surface portions of the receiving pipe sections that face each other in the pipe axis direction, thereby suppressing sludge accumulation and flow loss. can do.
[0018]
Moreover, since at least one of the two pipe portions and the sleeve are configured to be relatively slidable in the tube axis direction, the expansion and contraction of both the pipe portions caused by an earthquake, uneven settlement, or the like can be performed smoothly. At the same time, since the sleeve is made of synthetic resin that elastically deforms while keeping the cylindrical shape substantially following the bending of both pipe parts, the inner peripheral surface at the bent part of the sleeve is kept in a smooth state with little unevenness The flow resistance can be reduced.
[0019]
Furthermore, when the insertion tube portion is fitted and connected to the receiving tube portion, a sleeve is attached to one of the tube portions in advance, so that the sleeve serves as a guide member for guiding the fitting connection between the two tube portions. Function.
[0020]
Therefore, it is possible to effectively suppress the accumulation of sludge and loss of flow rate as compared with the conventional structure, while reliably and satisfactorily exhibiting the intended expansion and contraction function and bending function of the receiving pipe section and the insertion pipe section. In addition to this, it is possible to easily perform the fitting and connection work of the two pipe portions by using the sleeve for that purpose.
[0021]
In the characteristic configuration according to the second aspect of the present invention, the insertion tube portion is inserted and connected to each of the reception tube portions formed on both sides of the joint tube in the tube axis direction in a sealed state so as to expand and contract and bend freely. An expansion joint structure,
Over the inner peripheral surfaces of both insertion tube portions, a recess formed to be opened radially inward between the insertion-side tip surfaces of both insertion tube portions extends over the entire telescopic movement range of both tube portions. A synthetic resin sleeve that can be covered and elastically deforms while keeping the cylindrical shape substantially following the bending of both pipes is inserted and mounted in contact with the inner peripheral surfaces of both insertion pipe sections. In addition, at least one of the insertion tube portions and the sleeve are configured to be relatively slidable in the tube axis direction.
[0022]
According to the above-mentioned characteristic configuration, by the sleeve inserted and mounted in a contact state over the inner peripheral surfaces of both the insertion tube portions, over the entire telescopic movement range of both the tube portions, on the inner peripheral surface side of the joint pipe, In addition, since the recess formed between the insertion-side distal end faces of the two insertion tube portions and formed inward in the radial direction can be covered, sludge accumulation and flow loss can be suppressed.
[0023]
In addition, since at least one of the insertion tube portions and the sleeve are configured to be relatively slidable in the tube axis direction, each of the insertion tube portion and the reception tube portion caused by an earthquake, uneven settlement, or the like. The sleeve is made of a synthetic resin that can be smoothly expanded and contracted, and that elastically deforms while substantially maintaining the cylindrical shape following the bending of each insertion tube portion and the reception tube portion. Therefore, the inner peripheral surface at the bent portion of the sleeve can be maintained in a smooth state with little unevenness, and flow resistance can be reduced.
[0024]
Further, when the two insertion tube portions are fitted and connected to the receiving tube portion, a sleeve is attached to one of the tube portions in advance, so that the one insertion tube portion to which the sleeve is attached is connected to the joint tube. After inserting and connecting to one of the receiving pipes, when inserting and connecting the other receiving pipe to the other receiving pipe of the joint pipe, the sleeve serves as a guide member for guiding the fitting connection of both pipes. Function.
[0025]
Therefore, it is possible to effectively suppress the accumulation of sludge and loss of flow rate as compared with the conventional structure, while reliably and satisfactorily exhibiting the intended expansion and contraction function and bending function of the receiving pipe section and the insertion pipe section. In addition to this, it is possible to easily perform the fitting and connection work of the two pipe portions by using the sleeve for that purpose.
[0026]
A feature of the expansion joint structure according to claim 3 of the present invention resides in that fixing means for preventing relative sliding of the sleeve and the other pipe portion in the pipe axis direction are provided.
[0027]
According to the above-mentioned characteristic configuration, the insertion / mounting position of the sleeve does not shift with the fitting connection or bending of the two pipe portions, and while the intended expansion and contraction function and bending function are exhibited, over a long period of time. Sludge accumulation and flow loss can be effectively suppressed.
[0028]
A characteristic configuration of the expansion joint structure according to claim 4 of the present invention is that the sleeve is formed of a polyethylene resin into a cylindrical shape, and has a thickness in a range of 1.5 mm to 4.0 mm, preferably, The point lies in the range of 2.0 mm to 3.0 mm.
[0029]
According to the above-mentioned characteristic configuration, if the thickness of the polyethylene resin sleeve is 1.5 mm or more, it is possible to reduce radially inward bending deformation of the sleeve due to bending of both pipe portions, and If the thickness is 4.0 mm or less, there is no hindrance to the bending of both the tube portions.
[0030]
Furthermore, if the thickness of the sleeve made of polyethylene resin is 2.0 mm or more, it is possible to effectively suppress radially inward bending deformation of the sleeve due to bending of the two pipe portions, and the thickness of the sleeve Is 3.0 mm or less, both pipe portions can be smoothly bent.
[0031]
Therefore, the sleeve is elastically deformed while following the bending of the two pipe portions while substantially maintaining the cylindrical shape thereof, so that the flow area can be reduced without a large decrease in the flow path area.
[0032]
A characteristic configuration of the expansion joint structure according to claim 5 of the present invention is that a distal end on the insertion side of the inner peripheral surface of the sleeve is formed as a tapered surface having a larger diameter toward the distal end.
[0033]
According to the above-mentioned characteristic configuration, the step between the insertion-side tip portion of the sleeve and the inner peripheral surface of the pipe portion becomes smooth, and the accumulation of sludge and the flow rate loss can be effectively suppressed.
[0034]
BEST MODE FOR CARRYING OUT THE INVENTION
[First Embodiment]
FIGS. 1 to 4 show a telescopic pipe joint structure provided in a pipe system of a water pipe which is an example of a fluid pipe, and a pipe tube 1 formed on one end of a straight pipe cast water pipe P1. An insertion pipe portion 2 formed at one end of a straight tubular cast iron water pipe P2 is inserted and connected from the direction of the pipe axis X in a stretchable and bendable state. Among the three circumferential grooves 1c to 1e formed on the circumferential surface 1a, the first circumferential groove 1c located on the receiving side has a large-diameter-side inner circumferential surface 1a of the receiving tube portion 1 and the insertion tube portion 2. An elastic sealing material 3 made of synthetic rubber for sealing between the outer peripheral surface 2c of the tube and the second peripheral groove 1d located at the center side in the tube axis X direction is provided in the tube axis X. A metal retaining ring 8 formed in a substantially C-shape in a direction view and capable of being elastically deformed toward the enlarged diameter side; An elastic holding ring 9 made of synthetic rubber for holding the receiving tube 8 coaxially with the receiving tube portion 1 is attached, and the distal end of the outer peripheral surface of the receiving tube portion 2 is caused by an earthquake, uneven settlement, or the like. When the two pipe portions 1 and 2 move relative to each other by a certain amount or more, they come into contact with the retaining ring 8 in the tube axis X direction to prevent further relative separation movement of the two pipe portions 1 and 2. An annular retaining projection 2B is integrally formed.
[0035]
Range from the position where the distal end surface 2b of the insertion tube portion 2 contacts the stepped inner peripheral surface portion 1g on the back side of the reception tube portion 1 to the position where the retaining protrusion 2B contacts the retaining ring 8 Are configured in the range of expansion and contraction movement of the two pipe sections 1 and 2 in the pipe axis X direction, and the fitting connection between the receiving pipe section 1 and the insertion pipe section 2 includes both pipe sections. An accommodation A is provided to allow bending within the set angle range of 1, 2.
[0036]
In this accommodation A, the inner peripheral surface of the receiving end portion of the receiving tube portion 1 is slightly larger in diameter than the outer diameter of the retaining projection 2B of the insertion tube portion 2, and is larger toward the outer side. And the inner diameter of the bottom surface of the third peripheral groove 1e of the large-diameter inner peripheral surface 1a of the receiving tube portion 1 is made smaller than the outer diameter of the retaining protrusion 2B of the insertion tube portion 2. Is formed to have a slightly larger diameter, between the large-diameter inner peripheral surface 1a of the receiving tube portion 1 and the outer peripheral surface 2c of the insertion tube portion 2 and in the tube axis X direction of the elastic sealing material 3. On the outer side and on the inner side of the retaining ring 8 in the direction of the tube axis X, there are formed gaps S1 and S2 which allow bending of the two pipe portions 1 and 2 with the elastic seal material 3 as a fulcrum. ing.
[0037]
The small-diameter-side inner peripheral surface 1b of the corrosion-resistant lining layer 1D applied to the receiving tube portion 1 and the inlet tube portion 2 that is inserted and connected to the inner peripheral surface 1b of the corrosion-resistant lining layer 1D in a sealed state from the tube axis X direction. A step-like inner peripheral surface portion of the receiving tube portion 1 facing the insertion side distal end surface 2b of the insertion tube portion 2 in the tube axis X direction over the inner peripheral surface 2a of the corrosion-resistant lining layer 2A. 1 g, and has a length that covers a recess S formed to be opened radially inward over the entire expansion and contraction movement range of the two pipe parts 1 and 2. A synthetic resin sleeve 4 that elastically deforms while substantially maintaining the cylindrical shape following the bending is inserted and mounted in a state in which the sleeve 4 is in close contact with the entire inner surfaces 1b and 2a of the two pipe portions 1 and 2. At the same time, the two tube portions 1 and 2 and the sleeve 4 are configured to be relatively slidable in the tube axis direction.
[0038]
The sleeve 4 is configured to have a length slightly larger than the entire length of the receiving tube portion 1, and has an annular locking portion that enters the recessed portion S at the center of the outer peripheral surface in the tube axis X direction. When the insertion tube portion 2 is fitted and connected to the reception tube portion 1, the locking portion 4 </ b> A protruding from the sleeve 4 constitutes the recessed portion S. And at least one of the insertion-side distal end surface 2b of the insertion tube portion 2 and the stepped inner peripheral surface portion 1g of the reception tube portion 1 opposed to the insertion tube portion X in the tube axis X direction. It is configured such that the sleeve 4 is prevented from moving out of the predetermined mounting region with respect to the tube portions 1 and 2.
[0039]
Further, the sleeve 4 is formed of a polyethylene resin such as high-density polyethylene (HDPE) or high-performance polyethylene (HPPE) into a cylindrical shape, and has a thickness in the range of 1.5 mm to 4.0 mm, preferably. Is formed in a range of 2.0 mm to 3.0 mm, and further, the insertion distal end portion of the inner peripheral surface of the sleeve 4 is formed on a tapered surface 4 a having a larger diameter toward the distal end side.
[0040]
The outer diameter of the fitting tube portion of the sleeve 4 to be inserted and mounted on the insertion tube portion 2 is configured to be slightly larger than the inner diameter of the inner peripheral surface 2 a of the insertion tube portion 2. The fitting tube portion may be press-fitted into the insertion tube portion 2 so as to prevent relative movement between the sleeve 4 and the insertion tube portion 2 in the tube axis X direction.
[0041]
As shown in FIGS. 1 and 4, a fitting connection between the two pipe portions 1 and 2 is performed by a polyethylene resin sleeve 4 which is inserted and mounted in close contact over the inner peripheral surfaces of the two pipe portions 1 and 2. Since the depression S formed to open radially inward at the location can be reliably covered, it is possible to suppress the loss of flow rate due to the accumulation of sludge and turbulence.
[0042]
In addition, since at least one of the tube portions 1 and 2 and the sleeve 4 are configured to be relatively slidable in the tube axis X direction, the expansion and contraction of the tube portions 1 and 2 due to an earthquake, uneven settlement, or the like. The operation can be performed smoothly, and the sleeve 4 is made of a polyethylene resin that elastically deforms while substantially maintaining the cylindrical shape following the bending of the two pipe portions 1 and 2. Can be maintained in a smooth state with little unevenness, and therefore the flow resistance can be reduced without a large decrease in the flow channel area.
[0043]
[Second embodiment]
FIGS. 5 and 6 show another telescopic pipe joint structure provided in a pipe system of a water pipe which is an example of a fluid pipe, and a receiving pipe section 1 formed at one end of a cast iron joint pipe P3 has: An inlet pipe portion 2 formed at one end of a straight tubular cast iron water pipe P2 is inserted and connected from the direction of the pipe axis X in a stretchable and bendable state, and the inner periphery of the large diameter side of the receiving pipe portion 1 Of the surface 1a, between the tapered surface 1h formed so as to have a larger diameter toward the opening side and the outer peripheral surface 2c of the insertion tube portion 2, a synthetic rubber material for sealing between these two 1h and 2c. A pressing ring 5 capable of pressing the elastic seal material 3 in a compressed state from the tube axis X direction is provided on the flange portion 1A formed at the tip of the receiving tube portion 1 while the elastic seal material 3 is mounted. It is tightened and fixed from the tube axis X direction via bolts 6 and nuts 7.
[0044]
A circumferential groove 5a formed on the inner peripheral surface of the pressing ring 5 is formed of a metal having a substantially C-shape in a tube axis X direction, which bites into the outer peripheral surface 2c of the insertion tube portion 2 in a state capable of being elastically deformed toward the enlarged diameter side. And a bottom surface of the circumferential groove 5a is provided with a parallel sliding contact guide surface which allows the two pipe portions 1 and 2 to expand and contract within a certain range along the pipe axis X direction. And a tapered sliding contact guide surface that causes the lock ring 11 to bite and move inward in the radial direction as the two pipe portions 1 and 2 move away more than a certain amount.
[0045]
The range from the stepped inner peripheral surface portion 1g on the back side of the receiving tube portion 1 to the elastic sealing material 3 is configured as a range of expansion and contraction adjustment in the tube axis X direction when the two tube portions 1 and 2 are inserted and connected. The fitting A between the receiving pipe 1 and the insertion pipe 2 is provided with a flexibility A that allows the pipes 1 and 2 to bend within a set angle range. .
[0046]
In the accommodation A, the inner peripheral surface portion 1j located between the tapered surface 1h and the stepped inner peripheral surface portion 1g among the large-diameter-side inner peripheral surface 1a of the receiving tube portion 1 is formed by tilting the tapered surface 1h. Contrary to the direction, the inner peripheral surface 5b at both ends in the tube axis X direction of the pressing ring 5 is formed on the outer peripheral surface of the insertion tube portion 2 while being formed in a tapered surface having a larger diameter toward the step-shaped inner peripheral surface portion 1g side. By forming the diameter slightly larger than the outer diameter of the surface 2 c, between the large-diameter inner peripheral surface 1 a of the receiving tube 1 and the outer peripheral surface 2 c of the insertion tube 2, and On the outer side in the tube axis X direction and on the inner side of the elastic seal material 3 in the tube axis X direction, gaps S1 and S2 that allow the bending of the two pipe portions 1 and 2 with the elastic seal material 3 as a fulcrum are formed. It is constituted by forming.
[0047]
The insertion-side distal end surface 2b of the insertion tube portion 2 and the tube axis X direction extend over the small-diameter-side inner peripheral surface 1b of the receiving tube portion 1 and the inner peripheral surface 2a of the insertion tube portion 2. The recessed portion S formed to be opened radially inward between the stepped inner peripheral surface portion 1g of the receiving pipe portion 1 facing each other over the entire expansion and contraction movement range of both the pipe portions 1 and 2 A synthetic resin sleeve 4 having a covering length and elastically deforming while substantially maintaining a cylindrical shape following the bending of the two tube portions 1 and 2 is provided on the inner peripheral surface 1b of the both tube portions 1 and 2. , Are fitted so as to be in close contact with each other over the entire circumference, and the two tube portions 1 and 2 and the sleeve 4 are configured to be relatively slidable in the tube axis X direction.
[0048]
The outer diameter of the fitting tube portion of the sleeve 4 to be inserted and mounted on the insertion tube portion 2 is configured to be slightly larger than the inner diameter of the inner peripheral surface 2 a of the insertion tube portion 2. The fitting tube portion may be press-fitted into the insertion tube portion 2 so as to prevent relative movement between the sleeve 4 and the insertion tube portion 2 in the tube axis X direction.
[0049]
Further, the sleeve 4 is formed of a polyethylene resin such as high-density polyethylene (HDPE) or high-performance polyethylene (HPPE) into a cylindrical shape, and has a thickness in the range of 1.5 mm to 4.0 mm, preferably. Is formed in a range of 2.0 mm to 3.0 mm, and further, the insertion distal end portion of the inner peripheral surface of the sleeve 4 is formed on a tapered surface 4 a having a larger diameter toward the distal end side.
[0050]
Since the other configuration is the same as the configuration described in the first embodiment, the same components are denoted by the same reference numerals as those in the first embodiment, and description thereof will be omitted.
[0051]
[Third embodiment]
7 and 8 show another expansion joint structure provided in a pipe system of a water pipe which is an example of a fluid pipe, and receiving ports formed at both ends of a joint pipe P3 made of cast iron in the pipe axis X direction. In each of the pipe sections 1, an insertion pipe section 2 formed at one end of a straight tubular cast-iron water pipe P2 is slidably inserted along the pipe axis X direction in a stretchable and bendable state. Connected, between each receiving tube portion 1 and the insertion tube portion 2, when both the tube portions 1, 2 move relative to each other more than a predetermined distance along the tube axis X direction, the tube axis X direction A separation preventing means C is provided for contacting each other and preventing further separation movement.
[0052]
Also, of the inner peripheral surface 1k on the smaller diameter side of the receiving tube portion 1, between the tapered surface 1m formed to have a larger diameter toward the opening side and the outer peripheral surface 2c of the insertion tube portion 2, both of them. An elastic sealing material 3 made of synthetic rubber for sealing between 1 m and 2 c is mounted, and a fitting connection between the receiving pipe 1 and the insertion pipe 2 is provided with both pipes 1, 2 c. 2 is provided to allow bending within the set angle range of 2. Further, the elastic sealing material 3 is compressed from the tube axis X direction on the flange portion 1A formed at the tip of the receiving tube portion 1. A press wheel 5 which can be pressed by a screw is fastened and fixed via a bolt 6 and a nut 7.
[0053]
The detachment preventing means C is formed by forming an annular mounting groove 1n formed on the inner peripheral surface of the receiving tube portion 1 into a substantially C-shaped enlarged side as viewed in the tube axis X direction. A metal retaining ring 8 that can be elastically deformed, and a synthetic rubber elastic retaining ring 9 that holds the retaining ring 8 coaxially with the receiving tube portion 1 in a state that allows the diameter of the retaining ring 8 to be increased. At the end of the outer peripheral surface 2c of the insertion tube portion 2, when both the tube portions 1 and 2 move relative to each other by a certain amount or more due to an earthquake or uneven settlement, a retaining ring is provided. An annular retaining projection 2B is integrally formed with the tube 8 in contact with the tube axis X in the direction of the tube axis to prevent the relative detachment movement of the two tube sections 1 and 2 from occurring.
[0054]
In the above-mentioned accommodation A, the inner peripheral surface 1k of the small diameter side of the receiving tube portion 1 is configured to have a larger diameter than the outer diameter of the outer peripheral surface 2c of the insertion tube portion 2, and the inner peripheral surface 5c of the pressing ring 5 is inserted. The tapered surface is formed to have a diameter larger than the outer diameter of the outer peripheral surface 2c of the mouth tube portion 2 and to become larger as the distance from the mouth tube portion 1 in the tube axis X direction increases. Between the small-diameter inner peripheral surface 1k and the outer peripheral surface 2c of the insertion tube portion 2 and on the outer side of the elastic sealing material 3 in the tube axis X direction and the depth of the retaining ring 8 in the tube axis X direction. On the side, the space is formed by forming gaps S1 and S2 that allow the bending of the two pipe portions 1 and 2 with the elastic seal material 3 as a fulcrum.
[0055]
The inner peripheral surface of the joint pipe P3 extends over the inner peripheral surfaces 2a of the two inlet pipe parts 2 which are inserted and connected to the two receiving pipe parts 1 of the joint pipe P3 in a sealed state from the pipe axis X direction. And a length covering the recessed portion S formed to open radially inward between the insertion-side distal end surfaces 2b of the two insertion tube portions 2 on the surface side, and The synthetic resin sleeve 4 that elastically deforms while substantially maintaining the cylindrical shape following the bending of the insertion tube 2 is inserted and attached in a state in which the sleeve 4 is in close contact with the entire inner peripheral surface 2 a of both the insertion tube portions 2. At the same time, the two tube portions 1 and 2 and the sleeve 4 are configured to be relatively slidable in the tube axis direction.
[0056]
The outer diameter of the fitting tube portion of the sleeve 4 which is inserted and mounted on one of the insertion tube portions 2 is configured to be slightly larger than the inner diameter of the inner peripheral surface 2 a of the insertion tube portion 2. Alternatively, the fitting tube portion may be press-fitted into the insertion tube portion 2 so as to prevent relative movement between the sleeve 4 and one of the insertion tube portions 2 in the tube axis X direction.
[0057]
An annular locking portion 4A that penetrates into the recess S is integrally formed at a portion of the outer peripheral surface of the sleeve 4 that is deflected to one end side in the tube axis X direction. On the other hand, when the insertion tube portion 2 is fitted and connected, the locking portion 4A protruding from the sleeve 4 comes into contact with one of the insertion side distal end surfaces 2b of both the insertion tube portions 2 constituting the recessed portion S. Thus, the sleeve 4 is configured so as to prevent the sleeve 4 from moving out of the predetermined mounting area with respect to the two pipe portions 1 and 2.
[0058]
Further, the sleeve 4 is formed of a polyethylene resin such as high-density polyethylene (HDPE) or high-performance polyethylene (HPPE) into a cylindrical shape, and has a thickness in the range of 1.5 mm to 4.0 mm, preferably. Is formed in a range of 2.0 mm to 3.0 mm, and further, the insertion distal end portion of the inner peripheral surface of the sleeve 4 is formed on a tapered surface 4 a having a larger diameter toward the distal end side.
[0059]
[Other embodiments]
(1) In the above-described first to third embodiments, the sleeve 4 is press-fitted and fixed to the insertion tube portion 2 to prevent the sleeve 4 from moving relative to the insertion tube portion 2 in the tube axis X direction. Although the fixing method described above has been described, as shown in FIG. 9, a plurality of locations in the circumferential direction of the sleeve 4 may be tightened and fixed to the receiving pipe section 1 or the insertion pipe section 2 with bolts 10.
In this case, the mounting portion 4B of the sleeve 4, which is fastened and fixed by the bolt 10, may be configured to be thicker than other portions.
Further, as a fixing method, other fixing methods using an adhesive or the like may be adopted in addition to the above-described press-fitting method and the tightening and fixing method using bolts.
(2) In each of the above-described embodiments, the sleeve 4 inserted and mounted over the inner peripheral surfaces of both the tube portions 1 and 2 is configured as a single body. However, the sleeve 4 is divided into two in the tube axis X direction. One end side of each split sleeve body is attached to the inner peripheral surfaces of the pipe bodies 1 and 2 in a state where relative movement in the axial direction of the pipe is prevented, and the other end sides of both split sleeve bodies are connected to both pipes. Fitting and joining may be performed in a state of elastic deformation while closely maintaining the cylindrical shape following the bending of the bodies 1 and 2 and in close contact.
(3) In each of the above-described embodiments, a case has been described in which the inner diameters of the inner peripheral surfaces of the two pipe portions 1 and 2 where the sleeve 4 is inserted and mounted have the same diameter. If the inner diameters of the inner and outer peripheral surfaces of the sleeves 1 and 2 are different, the outer diameter of the sleeve 2 is changed accordingly.
[Brief description of the drawings]
FIG. 1 is a cross-sectional side view of an expansion pipe joint structure according to a first embodiment of the present invention.
FIG. 2 is a sectional view taken along line II-II in FIG.
FIG. 3 is a cross-sectional side view when an insertion tube is inserted and connected to a reception tube.
FIG. 4 is a sectional side view showing a bent state;
FIG. 5 is a sectional side view of a telescopic pipe joint structure showing a second embodiment of the present invention.
FIG. 6 is a sectional side view showing a bent state;
FIG. 7 is a sectional side view of an expansion joint structure showing a third embodiment of the present invention.
FIG. 8 is a sectional side view showing a bent state.
FIG. 9 is an enlarged cross-sectional side view of a main part of an expansion joint structure according to a fourth embodiment of the present invention.
FIG. 10 is a cross-sectional side view showing a conventional expansion joint structure.
FIG. 11 is a cross-sectional side view showing another conventional expansion joint structure.
FIG. 12 is a sectional side view showing another conventional expansion joint structure.
[Explanation of symbols]
A accommodation
P1 water pipe
P2 water pipe
P3 fitting pipe
S hollow
X pipe core
1 Receiving pipe section
1a Inner peripheral surface (larger diameter inner peripheral surface)
1b Inner peripheral surface (small diameter side inner peripheral surface)
2 insertion tube
2a Inner circumference
2b Inserting end face
2c Outer surface
4 sleeve
4A Locking part

Claims

受口管部に対して挿口管部が伸縮ならびに屈曲自在に密封状態で挿入接続されている伸縮管継手構造であって、
前記受口管部の内周面と挿口管部の内周面とに亘って、挿口管部の挿入側先端面とこれに管軸芯方向で相対向する受口管部の内周面部分との間において径方向内方に向かって開口形成される窪み部を両管部の全伸縮移動範囲に亘って覆うことが可能で、かつ、両管体の屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂製のスリーブが、両管部の内周面に接触する状態で挿入装着されているとともに、両管部の少なくとも一方とスリーブとが管軸芯方向で相対摺動自在に構成されている伸縮管継手構造。An expansion pipe joint structure in which the insertion pipe section is inserted and connected to the receiving pipe section in a sealed state so as to expand and contract and bend freely,
Over the inner peripheral surface of the receiving tube portion and the inner peripheral surface of the receiving tube portion, the insertion-side distal end surface of the receiving tube portion and the inner periphery of the receiving tube portion opposed to the front surface in the tube axis direction. It is possible to cover the depression formed in the radially inward between the surface portions over the entire range of expansion and contraction movement of the two tube portions, and to follow the bending of the two tube bodies and to form a cylindrical shape The sleeve is made of synthetic resin that is elastically deformed while maintaining substantially the same, and is inserted and mounted so as to be in contact with the inner peripheral surfaces of the two pipe parts. A telescopic pipe joint structure that is slidable.

継手管の管軸芯方向両側部に形成された受口管部の各々に、挿口管部が伸縮ならびに屈曲自在に密封状態で挿入接続されている伸縮管継手構造であって、
両挿口管部の内周面に亘って、両挿口管部の挿入側先端面間において径方向内方に向かって開口形成される窪み部を両管部の全伸縮移動範囲に亘って覆うことが可能で、かつ、両管体の屈曲に追従して円筒形状を略維持したまま弾性変形する合成樹脂製のスリーブが、両挿口管部の内周面に接触する状態で挿入装着されているとともに、両挿口管部の少なくとも一方とスリーブとが管軸芯方向で相対摺動自在に構成されている伸縮管継手構造。An expansion pipe joint structure in which an insertion pipe section is inserted and connected in a sealed state so that the insertion pipe section can expand and contract and bend freely, in each of the receiving pipe sections formed on both sides of the joint pipe in the pipe axis direction,
Over the inner peripheral surfaces of both insertion tube portions, a recess formed to be opened radially inward between the insertion-side tip surfaces of both insertion tube portions extends over the entire telescopic movement range of both tube portions. A synthetic resin sleeve that can be covered and elastically deforms while keeping the cylindrical shape substantially following the bending of both pipes is inserted and mounted in contact with the inner peripheral surfaces of both insertion pipe sections. A telescopic pipe joint structure in which at least one of the insertion pipe sections and the sleeve are configured to be relatively slidable in the pipe axis direction.

前記スリーブと他方の管部との管軸芯方向での相対摺動を阻止する固定手段が設けられている請求項１又は２記載の伸縮管継手構造。The expansion joint structure according to claim 1 or 2, further comprising fixing means for preventing relative sliding of the sleeve and the other pipe portion in the pipe axis direction.

前記スリーブが、ポリエチレン樹脂で円筒状に成形されているとともに、それの厚みが１．５ｍｍ〜４．０ｍｍまでの範囲、好ましくは、２．０ｍｍ〜３．０ｍｍの範囲に構成されている請求項１〜３のいずれか１項に記載の伸縮管継手構造。The sleeve is formed of a polyethylene resin into a cylindrical shape, and has a thickness in a range of 1.5 mm to 4.0 mm, preferably in a range of 2.0 mm to 3.0 mm. The telescopic pipe joint structure according to any one of claims 1 to 3.

前記スリーブの内周面の挿入側先端部が、先端側ほど大径となるテーパー面に形成されている請求項１〜４のいずれか１項に記載の伸縮管継手構造。The telescopic pipe joint structure according to any one of claims 1 to 4, wherein an insertion-side distal end of the inner peripheral surface of the sleeve is formed as a tapered surface having a larger diameter toward the distal end.