JP2004052972A

JP2004052972A - Coupling and fastening member for coupling

Info

Publication number: JP2004052972A
Application number: JP2002213937A
Authority: JP
Inventors: Yoshiyuki Iwahara; 岩原　善行
Original assignee: Onda Mfg Co Ltd
Current assignee: Onda Mfg Co Ltd
Priority date: 2002-07-23
Filing date: 2002-07-23
Publication date: 2004-02-19
Anticipated expiration: 2022-07-23
Also published as: JP4213424B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coupling capable of reducing the diameter of a fastening member with light fastening force and eliminating a failure caused by insufficient diameter reduction of the fastening member. <P>SOLUTION: This coupling 12 constituted so that a pipe 11 may be connected is mainly constituted of a substantially cylindrical coupling body 13, a cylindrical pressing ring 15 as the fastening member and a push ring 17 constituted of a nut. At the inside of the coupling body 13, a substantially cylindrical inner cylinder part 14 is disposed. The pressing ring 15 is formed by divided pieces 15a forming four wedge shapes and a connecting part 15b for connecting each of the divided pieces 15a. The pressing ring 15 is constituted so that the diameter may be reduced by reducing a gap between each of the divided pieces 15a since a boundary part of the divided pieces 15a and the connecting part 15b or the connecting part 15b itself is bent or the connecting part 15b is broken to separate each of the divided pieces 15a. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、水道配管、温水配管、床暖房、ロードヒーティング等に使用されるパイプ用の継手及び継手用の締付部材に関するものである。
【０００２】
【従来の技術】
従来、この種の継手は、筒状をなし、内周から内筒部が突設された継手本体と、継手本体の先端部に螺合接続される筒状の押輪と、継手本体と押輪との間に配設されるＣリング状をなす締付部材とより主に構成されている。当該継手は、継手本体の先端側に締付部材を配置し、手作業で押輪を継手本体の先端部に緩やかに螺合接続して組み立てられる。そして、組み立てられた継手は、継手本体の基端部を水道配管に接続し、次いで、パイプの端部を押輪内を介して継手本体内に挿入し、内筒部に外嵌させることによって組み付けが行われる。
【０００３】
組み付けの後、スパナ等を使用して継手本体に押輪を螺合すると、同押輪を締め付けるに従って、締付部材が継手本体内に押し込まれる。すると、Ｃリング状をなす締付部材は縮径し、パイプの外周面を締め付ける。そして、継手本体に押輪が固く螺合接続された状態で締付部材が継手本体と押輪との間に位置決めされ、パイプの抜け出しが規制される。
【０００４】
【発明が解決しようとする課題】
ところが、上記従来の継手においては、締付部材は金属製であり、同締付部材を全体的に曲げて縮径させるには押輪を非常に強い力で締め付けなければならないという問題がある。また、締付部材が縮径する際に生じる反力によって継手本体に対する押輪の締め付けが不十分になったり、締付部材が不均一に曲がって縮径したり等するおそれもある。この場合、締付部材によるパイプの締め付けも不十分となり、継手からパイプが抜け出したり、パイプの内周面と内筒部の外周面との間に隙間が形成され、同隙間から漏水したり等のような不具合が発生するという問題もあった。
【０００５】
本発明は、上記のような従来技術に存在する問題点に着目してなされたものである。その目的とするところは、締付部材を軽い締付力で縮径させることができ、同締付部材の縮径が不十分であることに起因する不具合を解消することができる継手及び継手用の締付部材を提供することにある。
【０００６】
【課題を解決するための手段】
上記の目的を達成するために、請求項１に記載の継手の発明は、筒状をなす継手本体と、同継手本体の一端部に螺合される押輪と、当該継手本体と押輪との間に配設される筒状の締付部材とを備え、該継手本体内にパイプの端部が挿入された状態で継手本体に押輪を螺合するに伴い、該締付部材が縮径することによって該パイプの外面を締め付け、同パイプを抜け止めするように構成した継手であって、前記締付部材は、複数の分割片と、各分割片をそれぞれの間に隙間が設けられた状態で互いに接続するための接続部とから形成されていることを特徴とするものである。
【０００７】
請求項２に記載の継手の発明は、請求項１に記載の発明において、前記締付部材は、その外周面が継手本体に押輪を螺合する方向に向かうに従い縮径するテーパ状に形成されていることを特徴とするものである。
【０００８】
請求項３に記載の継手の発明は、請求項１又は請求項２に記載の発明において、前記接続部は、継手本体に対するパイプの挿入方向の前進側となる各分割片の端部を接続するものであることを特徴とするものである。
【０００９】
請求項４に記載の継手の発明は、請求項１又は請求項２に記載の発明において、前記接続部は、継手本体に対するパイプの挿入方向の後退側となる各分割片の端部を接続するものであることを特徴とするものである。
【００１０】
請求項５に記載の継手用の締付部材の発明は、パイプを接続可能な継手を構成する筒状をなす継手本体と、同継手本体の一端部に螺合される押輪との間に配設され、該継手本体内にパイプの端部が挿入された状態で継手本体に押輪を螺合するに伴って縮径し、該パイプの外面を締め付けることによって同パイプを抜け止めするように構成した継手用の締付部材であって、複数の分割片と、各分割片をそれぞれの間に隙間が設けられた状態で互いに接続するための接続部とから筒状に形成されていることを特徴とするものである。
【００１１】
【発明の実施の形態】
（第１実施形態）
以下、本発明を具体化した第１実施形態を図面に基づいて詳細に説明する。
【００１２】
図１〜図３（ａ），（ｂ）に示すように、パイプ１１を接続可能に構成された継手１２は、略円筒状の継手本体１３と、締付部材としての円筒状の押圧リング１５と、ナットよりなる押輪１７とから主に構成されている。また、継手本体１３の内部には略円筒状の内筒部１４が配設されている。押圧リング１５と押輪１７との間には、円環状をなす座金１６が介在されている。前記継手本体１３、内筒部１４、押圧リング１５、座金１６及び押輪１７は、それぞれ合金（真鍮、青銅等）等の金属材料により形成されている。前記パイプ１１は、ポリエチレン、ポリブテン等の合成樹脂により円筒状に形成されている。
【００１３】
まず、前記継手本体１３について説明する。
継手本体１３の基端部の外周面には、第１雄ねじ部１８が螺刻され、水道配管等の管体（図示せず）と螺合可能になっている。継手本体１３の先端部の外周面には、第２雄ねじ部２７が螺刻されている。また、継手本体１３の長手方向の中央部における内周面には、当接面１９が継手本体１３の軸線と直交するように円環状に設けられている。継手本体１３内には前記当接面１９を境界として、当接面１９より基端側（図２（ａ）では右端側）には輸送液体が流通可能な導入路２０が形成され、当接面１９よりも先端側（図２では右端側）には、第１雌ねじ部２１が螺刻されている。
【００１４】
当該第１雌ねじ部２１は、継手本体１３と別体に形成された前記内筒部１４の基端部に螺刻された第３雄ねじ部３０と螺合可能に形成されている。そして、内筒部１４の基端面が前記当接面１９に当接するまで前記第３雄ねじ部３０を第１雌ねじ部２１に螺合することにより、内筒部１４が継手本体１３に螺合接続されている。なお、前記第１雌ねじ部２１と第３雄ねじ部３０とは嫌気性の接着剤により接着される。
【００１５】
前記内筒部１４の先端外周縁には、同内筒部１４の先端に向かうに従い縮径する第２テーパ面３１が形成され、その第２テーパ面３１より基端側の外周面には、収容溝３２が内筒部１４の外周全体にわたって凹設されている。この収容溝３２には、ゴム材料製の断面円形状をなすシール部材としてのシールリング３３が４本嵌着されている。これらシールリング３３の外径はそれぞれ内筒部１４の外径と同じ長さに設定され、シールリング３３の厚みが収容溝３２の深さと同じになるように設定されている。
【００１６】
当該内筒部１４の外周面には同内筒部１４の基端から収容溝３２まで周方向に沿って螺旋状に延びてその収容溝３２と連なり、さらに、収容溝３２から第２テーパ面３１にまで螺旋状に延びる凹溝１４ａが凹部として凹設されている。即ち、凹溝１４ａは収容溝３２に嵌着されたシールリング３３を跨いで内筒部１４の先端から基端まで延びるように形成されている。
【００１７】
前記継手本体１３の先端側の内周面と内筒部１４の外周面との間には、パイプ１１を継手本体１３内に挿入するための円環状の挿入空間３７が形成されている。同挿入空間３７の内奥部には、前記当接面１９に向かうに従い縮径する傾斜壁３８が形成され、その傾斜壁３８より当接面１９側には円環状の縮径部３９が形成されている。この縮径部３９にはゴム材料製の断面円形状をなすＯリング４０が嵌着されている。
【００１８】
継手本体１３の略中央部には、平面略円形状をなす貫通孔２３が１箇所形成されている。この貫通孔２３には、図１に示すように、ポリアセタール等の合成樹脂製の略円筒状をなすカラー２４が嵌入されている。同カラー２４内にはポリアセタール等の合成樹脂製の略円柱状をなすシャフト２５が嵌挿されている。同シャフト２５は、パイプ１１の挿入状態に応じて貫通孔２３内を継手本体１３の軸線と直交する方向に移動可能に構成されている。つまり、パイプ１１が挿入されていない状態ならば、シャフト２５は、その外端部が貫通孔２３内に没入し、かつ内端部が貫通孔２３から継手本体１３内に突出する位置となる。これとは逆に、パイプ１１が挿入された状態ならば、シャフト２５は、その外端部が貫通孔２３から外方に突出し、かつ内端部が貫通孔２３に没入する位置となる。
【００１９】
次に、前記押輪１７について説明する。
押輪１７の基端部の内周面には、前記継手本体１３の第２雄ねじ部２７と螺合可能な第２雌ねじ部４１が螺刻されている。この第２雌ねじ部４１より先端側には、係止面４４が押輪１７の軸線と直交するように円環状に形成されている。押輪１７の先端部の内周面には収容凹所４５が全周にわたって凹設されている。この収容凹所４５には、パイプ１１の継手１２からの抜け出しを防止するためのゴム材料製の断面円形状をなす抜け出し防止リング４６が嵌着されている。
【００２０】
次いで、前記押圧リング１５について説明する。
前記継手本体１３の先端側の内周面には、同継手本体１３に押輪１７を螺合する方向、つまり継手本体１３の先端側から内部に向かう方向に向かうに従って縮径する第１テーパ面２９が形成されている。押圧リング１５の外周面は、この継手本体１３の第１テーパ面２９に対応して、継手本体１３に押輪１７を螺合する方向に向かうに従い縮径する第３テーパ面４７となっている。そして、押圧リング１５は、継手本体１３と押輪１７との間に配設されている。
【００２１】
この状態で前記座金１６は、押圧リング１５と押輪１７の係止面４４との間に介在されている。また、押圧リング１５の内周面には、パイプ１１を継手本体１３内に抜け止めするための凹凸面が全面にわたって形成されている。加えて、パイプ１１の挿入方向の後退側、つまりパイプ１１の入口側となる押圧リング１５の先端部において、その内周縁には面取部１５ｃが設けられている。
【００２２】
当該押圧リング１５は、４個の楔状をなす分割片１５ａと、各分割片１５ａをそれぞれ接続する接続部１５ｂとから形成されている。また、同接続部１５ｂは、パイプ１１の挿入方向の前進側となる各分割片１５ａの基端部をそれぞれ接続している。そして、押圧リング１５は、分割片１５ａと接続部１５ｂとの境界部分、あるいは接続部１５ｂ自身が曲がったり、接続部１５ｂが折れて各分割片１５ａが切離されたり等して、各分割片１５ａの間の切り欠き、つまり隙間が縮まることにより、縮径可能に構成されている。
【００２３】
同押圧リング１５は、金属筒の周壁に軸線方向へ延びる切り欠きを周方向へ等間隔おきに４箇所形成することによって製造されている。つまり、金属筒の周壁を切り欠く際、同金属筒の一端縁を切削することなく周壁の極僅かな一箇所を残すことにより、この残された一箇所が接続部１５ｂ、切り欠き間に挟まれた周壁部分が分割片１５ａとして構成されている。
【００２４】
前記接続部１５ｂの軸線方向の長さが短いほど、接続部１５ｂでの曲がり、折れ等が発生しやすくなるため押圧リング１５を縮径させやすくなる。しかし、過剰に短いと切削作業がしづらくなり、また強度不足で継手本体１３への組み付け時等に各分割片１５ａが切離されてしまうおそれがある。なお、接続部１５ｂの軸線方向の長さを過剰に長くすると、接続部１５ｂが曲がったり、折れたり等せず、押圧リング１５が縮径すらしなくなるおそれがある。従って、接続部１５ｂの軸線方向の長さは、押圧リング１５を容易に縮径させることができる程度に短く、かつ切削作業を行いやすく所望する強度を維持することができる程度に長くすることが好ましい。具体的に接続部１５ｂの軸線方向の長さは、好ましくは０．０５〜２．０ｍｍであり、より好ましくは０．１〜１．０ｍｍであり、さらに好ましくは０．２〜０．５ｍｍである。
【００２５】
また、各分割片１５ａ間の隙間が幅広なほど、押圧リング１５の縮径率が大きくなり、また切削作業がしやすくなる。しかし、隙間が過剰に幅広となると、縮径した押圧リング１５でパイプ１１の外周面を締め付ける際、各分割片１５ａ間に大きな隙間が形成されてしまう。この状態では、外部から加わる衝撃又は振動、継手１２に対するパイプ１１の回転、移動等により各分割片１５ａがパイプ１１に対して位置ずれするおそれがある。すると、各分割片１５ａでパイプ１１の外周面を均一に締め付けることができなくなり、パイプ１１の引き抜きに対する抗力の低減、水のシール性の低下等のような、締付部材の締付力が不十分となることに起因する不具合が発生するおそれがある。一方、各分割片１５ａ間の隙間が過剰に幅狭となれば、押圧リング１５は、パイプ１１の外周面を十分に締め付けるまで縮径することができず、パイプ１１の抜け出し等のような締付部材の締付力が不十分であることに起因する不具合が発生するおそれがある。従って、各分割片１５ａ間の隙間は、パイプ１１の外周面を十分に締め付けるまで縮径させることができる程度に幅狭で、かつ縮径した状態で各分割片１５ａ間に隙間がない、又は若干の余裕がある程度に幅広とすることが好ましい。
【００２６】
次に、上記のように構成された継手１２の作用を説明する。
さて、継手１２の組み付け作業は、次のようにして行われる。すなわち、図２（ａ），（ｂ）に示したように、まず、継手本体１３の先端側に押圧リング１５と座金１６が配置された状態で、継手本体１３に押輪１７が手作業で緩やかな締め付けで螺合される。次いで、継手本体１３の第１雄ねじ部１８が管体（図示せず）に接続される。そして、継手本体１３内の挿入空間３７にパイプ１１の端部が押輪１７内を介して挿入され、パイプ１１の端部が内筒部１４に外嵌される。
【００２７】
図３（ａ），（ｂ）に示したように、パイプ１１の端部が挿入空間３７に挿入されると、パイプ１１の端部がシャフト２５の内端部に押し当たって、シャフト２５は継手本体１３の外周面に向かって移動される。その結果、シャフト２５の外端部は、貫通孔２３内に没入した状態から外方へ突出した状態へと変位される。このため、パイプ１１の端部の継手本体１３の挿入空間３７への挿入深さを視認することができる。
【００２８】
その後、継手本体１３に押輪１７が手作業で固く締め付けられ、仮締め状態で螺合される。このとき、押圧リング１５は、押輪１７を締付けるに従って、第３テーパ面４７を第１テーパ面２９に摺接させながら継手本体１３の内奥へ押し込まれる。すると、第１テーパ面２９への第３テーパ面４７の摺接により、各分割片１５ａが接続部１５ｂを中心にそれぞれの間の隙間を押圧リング１５の先端側から徐々に縮める方向へ回動され、押圧リング１５が縮径され始める。そして、押圧リング１５を縮径させる力が接続部１５ｂの強度を上回ったとき、各接続部１５ｂが破断し、各分割片１５ａが切離される。
【００２９】
押輪１７を仮締め状態としたときに切離された各分割片１５ａは、それぞれが継手本体１３とパイプ１１との間に打ち込まれた楔として機能する。つまり、当該押圧リング１５は、切離された各分割片１５ａを継手本体１３とパイプ１１との間に押し込む力を主に必要とし、従来の締付部材のように締付部材全体を湾曲させて縮径変形させるための大きな力を必要としない。この各分割片１５ａを継手本体１３とパイプ１１との間に押し込む力は、手作業でも十分に足る力である。従って、押輪１７の仮締め作業を軽い力で行うことが可能となる。
【００３０】
その後、各分割片１５ａは、押輪１７を締付けるに従って、座金１６を介してそれぞれに均等な力が加えられ、継手本体１３の内奥へ押し込まれる。そして、継手本体１３との間に４つの分割片１５ａが押し込まれたパイプ１１は、各分割片１５ａによって均等な力で外周面を締め付けられ、継手１２に仮止めされる。この状態でパイプ１１の屋内における位置調節、配置調節等が行われる。このパイプ１１の位置調節、配置調節等が行われた後、継手本体１３に押輪１７がスパナ等の工具を使用して固く締め付けられ、本締め状態で螺合される。
【００３１】
図３（ａ）に示したように、継手本体１３に押輪１７が本締め状態とされたとき、各分割片１５ａの基端が継手本体１３の最内奥へ達し、各分割片１５ａはそれぞれが継手本体１３と押輪１７との間で位置決め固定される。この状態で、各分割片１５ａは、図３（ｂ）に示したように、全体として略真円形状をなしており、それぞれの内面をパイプ１１の外周面に均一に圧接させることにより、パイプ１１を強固に締め付ける。また、この状態で各分割片１５ａ間にはほとんど隙間がないため、各分割片１５ａは、互いの移動を規制しあい、かつそれぞれの内面をパイプ１１の外周面に圧接させ、内面の凹凸をパイプ１１の外周面に食い込ませることにより、継手１２内からのパイプ１１の抜け出しを規制する。その結果、継手本体１３と押輪１７との間に位置決めされた各分割片１５ａにより、パイプ１１は継手本体１３内に強固に抜け止めされる。また、各分割片１５ａは、それぞれが楔として機能しており、パイプ１１の引き抜き力に対して強い抗力を発揮する。
【００３２】
一方、各分割片１５ａによって締め付けられたパイプ１１は、内筒部１４の外周面に圧接され、収容溝３２内及び凹溝１４ａ内に入り込む。収容溝３２内に入り込んだパイプ１１は各シールリング３３に圧接され、その結果、シールリング３３は圧接に伴って弾性変形し、互いに面接触するとともに、収容溝３２の内面及びパイプ１１の内周面に対しても面接触される。そして、パイプ１１の内周面と内筒部１４の外周面との間における水に対するシール機能がシールリング３３により発揮され、かつシールリング３３の水圧に対する耐圧性が向上される。
【００３３】
上記のようにして継手１２の組み付け作業が行われた後、同継手１２に所定の水圧を加えることで水圧試験が行われる。同水圧試験においては、各分割片１５ａによるパイプ１１の締め付けが十分であるかが確認される。すなわち、パイプ１１の締め付けが不十分であるとき、パイプ１１の内周面は、内筒部１４の外周面に配設された各シールリング３３に対して軽く接触した状態となる。この状態で水圧試験を行うと、同シールリング３３とパイプ１１との間から漏出した水が凹溝１４ａを通り、挿入空間３７を介して継手本体１３と押輪１７との接続部分等から流出する。この結果、各分割片１５ａによるパイプ１１の締め付けが不十分であることが作業者により確認され、押輪１７の増し締めが行われる。
【００３４】
以上詳述した第１実施形態によれば次のような効果が発揮される。
・　パイプ１１を締め付け、かつ抜け止めするための押圧リング１５は、４個の楔状をなす分割片１５ａと、各分割片１５ａをそれぞれ接続する接続部１５ｂとから形成されている。そして、継手本体１３に押輪１７を螺合し、締め付けて押圧リング１５を縮径させるときには、接続部１５ｂが破断することにより、各分割片１５ａが切離される。このため、各分割片１５ａを継手本体１３の内奥へ押し込む力を主に必要とし、押圧リング１５全体を湾曲させて縮径変形させるための力を加える必要はない。従って、押輪１７の締付力を軽くすることができ、その軽い締付力で押圧リング１５を容易に縮径させることができる。
【００３５】
・　また、押圧リング１５の接続部１５ｂが破断して切離された各分割片１５ａは、それぞれが継手本体１３の内周面とパイプ１１の外周面との間に打ち込まれた楔として機能する。そして、各分割片１５ａは、全体として略真円形状を維持しながら、それぞれの内面をパイプ１１の外周面に均一に圧接させる。このため、パイプ１１が強固に締め付けられ、抜け出しが規制されつつ引き抜きに対しては強い抗力が発揮され、またパイプ１１の内周面と内筒部１４の外周面との間における水に対するシール機能が向上される。従って、押圧リング１５の縮径が不十分であることに起因する不具合の発生を解消することができる。
【００３６】
・　また、接続部１５ｂは、パイプ１１の挿入方向の前進側となる押圧リング１５の基端部に配置されている。このため、パイプ１１の挿入時には、同パイプ１１が押圧リング１５に接触しても、接続部１５ｂを中心に分割片１５ａが若干移動し、開口径を拡げることにより、パイプ１１の挿入時の引っ掛かりを抑制することができる。
【００３７】
・　また、接続部１５ｂが押圧リング１５の基端部に配置されていることから、押輪１７の仮締め時には、押圧リング１５を縮径させようとする力が接続部１５ｂにいち早く加わり、同接続部１５ｂが迅速に破断される。このため、各分割片１５ａがそれぞれの内周面をパイプ１１の外周面に均等に接触させ、これを締め付けることができる。従って、継手本体１３に対して押輪１７を仮締めした状態で、パイプ１１を継手１２に確実に仮止めすることができる。
【００３８】
・　また、押圧リング１５の先端内周縁には面取部１５ｃが設けられている。同面取部１５ｃは、パイプ１１の挿入時に同パイプ１１の端面を押圧リング１５に接触させにくくするとともに、接触時にはその力を受け流すことができ、パイプ１１の挿入を容易に行うことができる。
【００３９】
・　また、図３（ｂ）に示したように、パイプ１１を締め付けた状態で、各分割片１５ａは、全体として略真円形状をなし、それぞれの間には隙間がほとんど形成されないように構成されている。従って、例えば過剰な水圧が加わる等して継手１２内から水が漏出しようとする場合にも、同水を押圧リング１５でシールすることができる。
【００４０】
（第２実施形態）
以下、本発明を具体化した第２実施形態を図面に基づいて詳細に説明する。なお、この第２実施形態では第１実施形態と異なる点を中心に説明する。
【００４１】
図４に示すように、押圧リング１５は、４個の楔状をなす分割片１５ａと、各分割片１５ａをそれぞれ接続する接続部１５ｂとから形成されている。そして、同接続部１５ｂは、パイプ１１の挿入方向の後退側となる各分割片１５ａの先端部をそれぞれ接続している。従って、各接続部１５ｂは、第１実施形態のものと比較してその厚みが厚くなっており、予想外の力が加わったりしたとき等に接続部１５ｂが破断してしまうことを防止することができる。
【００４２】
さて、第２実施形態の継手１２の組み付け作業は、継手本体１３内の挿入空間３７へのパイプ１１の端部の挿入まで、第１実施形態と同様に行われ、その後、継手本体１３に押輪１７が手作業で固く締め付けられ、仮締め状態で螺合される。押輪１７を仮締めするとき、押圧リング１５は、押輪１７を締付けるに従って、第３テーパ面４７を第１テーパ面２９に摺接させながら継手本体１３の内奥へ押し込まれる。すると、第１テーパ面２９への第３テーパ面４７の摺接により、各分割片１５ａが接続部１５ｂを中心にそれぞれの間の隙間を押圧リング１５の基端側から徐々に縮める方向へ回動される。さらに、押圧リング１５の先端部を縮径させようとする力が各接続部１５ｂに加わり、各接続部１５ｂがそれぞれ湾曲したり、折れ曲がったり等して押圧リング１５が縮径され始める。そして、パイプ１１は、その外周面に各分割片１５ａの内周面の基端部が接触されることにより、軽い力で継手１２に仮止めされる。
【００４３】
この後、パイプ１１の屋内における位置調節、配置調節等が行われた後、継手本体１３に押輪１７がスパナ等の工具を使用して固く締め付けられ、本締め状態とされる。この押輪１７を本締め状態とするとき、押圧リング１５を縮径させる力が接続部１５ｂの強度を上回り、各接続部１５ｂが破断して各分割片１５ａがそれぞれ切離される。切離された各分割片１５ａは、それぞれがパイプ１１の外周面を均一に締付けながらその基端が継手本体１３の最内奥へ達したとき、継手本体１３と押輪１７との間で位置決め固定される。そして、全体で略真円形状をなす各分割片１５ａにより、均一に圧接されたパイプ１１は、強固に締め付けられ、継手１２内からの抜け出しが規制される。
【００４４】
以上詳述した第２実施形態によれば次のような効果が発揮される。
・　第２実施形態の継手１２の押圧リング１５は、その接続部１５ｂがパイプ１１の挿入方向の後退側となる押圧リング１５の先端部に配置されている。同接続部１５ｂは、押輪１７を仮締めするときには破断せず、押輪１７を本締めするときに破断される。つまり、継手本体１３に押輪１７を手作業で螺合するとき、押圧リング１５を縮径させるために主に必要となる力は、各接続部１５ｂを中心に分割片１５ａをそれぞれ回動させる力である。このため、第１実施形態と比較して、接続部１５ｂを破断させるための力は必要なく、その分、手作業時に加える力を低減することができる。従って、継手本体１３に押輪１７を仮締めするときに必要とする力を軽減することができる。
【００４５】
・　また、接続部１５ｂが押圧リング１５の先端部に配置されていることから、パイプ１１の挿入時、パイプ１１が押圧リング１５に引っ掛かっても、押圧リング１５の先端部の開口径を維持することができる。従って、パイプ１１の挿入時に開口径が狭まる等の不具合の発生を抑えることができる。
【００４６】
・　また、接続部１５ｂを押圧リング１５の先端部に配置した場合、その厚みは、押圧リング１５の基端部に配置した場合と比較して厚くなる。従って、押圧リング１５の接続部１５ｂにおける強度の向上を図ることができる。
【００４７】
・　また、継手本体１３に押輪１７を仮締めした状態で各分割片１５ａが切離されておらず、またパイプ１１は軽い力で仮止めされている。このため、パイプ１１の挿入不足、接続違い等の場合、パイプ１１の引き抜き及び再挿入を行いやすく、パイプ１１の挿脱作業を簡易なものとすることができる。
【００４８】
なお、前記実施形態を次のように変更して構成することもできる。
・　実施形態では、分割片１５ａ及び接続部１５ｂをそれぞれ４個としたが、これに限らず、それぞれ２又は３個、あるいは５個以上としてもよい。この分割片の個数は、少ないほど分割片間の隙間が広くなるため、同隙間が狭まりやすく、締付力を軽減することが可能となるが、隙間が過剰に広いと水に対するシール性は低下してしまう。一方、分割片の個数が多いほど分割片間の隙間は狭くなり、水に対するシール性は向上するが、切削作業がしづらくなるとともに、締付力が増加する。従って、分割片の個数は、水に対するシール性を維持しつつ、締付力を軽減させることができ、かつ切削作業をしやすい程度の個数とすることが好ましい。具体的に分割片の個数は、好ましくは３〜１０個であり、より好ましくは４〜６個である。また、この場合、各分割片は等間隔おきに配置することが好ましい。このように各分割片を等間隔おきに配置することによって、押圧リング１５は略真円状を維持しながら均等に縮径することができ、パイプの外周面を均一に締め付けることができる。
【００４９】
・　実施形態では、接続部１５ｂを押圧リング１５の基端部に設けたが、これに限らず、例えば押圧リング１５の先端部又は中間部に設けてもよい。また、接続部１５ｂは、各分割片１５ａの間に１つのみ設けることに限らず、２つ以上設けてもよい。
【００５０】
・　実施形態では、金属筒に切削加工を施すことによって分割片１５ａ及び接続部１５ｂを一体形成したが、これに限らず、分割片１５ａと接続部１５ｂとをそれぞれ別体として形成し、後に組み合わせて押圧リング１５としてもよい。例えば、複数の分割片１５ａをそれぞれ形成し、これら分割片１５ａをそれぞれ接着樹脂、接着剤、粘着テープ、ハンダ等の接合手段により接続して押圧リング１５を形成してもよい。この場合、当該接合手段によって形成された箇所が接続部１５ｂとなる。
【００５１】
・　実施形態では、継手本体１３に第１テーパ面２９を設け、これと対応して押圧リング１５に第３テーパ面４７を設けて押圧リング１５を縮径させるように構成した。しかし、これに限らず、例えば押輪１７の内周面にテーパ面を設け、これと対応するテーパ面を押圧リング１５の外周面に設けてもよい。すなわち、継手本体１３の内周面に内ねじとして雌ねじを螺刻し、押輪１７の外周面に前記内ねじと螺合可能な外ねじとして雄ねじを螺刻する。そして、押輪１７の内周面には、押輪１７の螺合方向へ向かうに従って拡径するテーパ面を形成し、これと対応して押圧リング１５の外周面を押輪１７の螺合方向へ向かうに従って拡径するテーパ状としてもよい。この場合も、押輪１７の螺合に伴い、押圧リング１５を縮径させることができる。
【００５２】
・　実施形態では、シールリング３３を４本設けたが、１〜３本のいずれか又は５本以上のシールリング３３を収容溝３２に嵌着してもよい。なお、このとき、使用されるシールリング３３の本数に対応させて収容溝３２の大きさを変更してもよい。又は、厚みが収容溝３２の深さと同じ又は若干異なるように設定されているゴム材料製の断面長方形状をなすシールリングに変えてもよい。
【００５３】
・　実施形態では、内筒部１４と継手本体１３とを螺合関係により取付可能に形成したが、継手本体１３の第１雌ねじ部２１及び内筒部１４の第３雄ねじ部３０を省略し、内筒部１４の基端部と継手本体１３とを嵌合関係により取付可能に構成してもよい。
【００５４】
・　実施形態では、内筒部１４と継手本体１３とを別体に構成したが、継手本体１３に内筒部１４を一体形成してもよい。
・　実施形態では、凹溝１４ａを内筒部１４の周方向に沿って螺旋状に延びるように形成したが、収容溝３２と連通するように、凹溝１４ａを内筒部１４の長さ方向に沿って直線状、波形状に延びるように形成してもよい。
【００５５】
・　実施形態では、内筒部１４に凹溝１４ａを凹設したが、内筒部１４の外面に凸部を形成し、その凸部により押輪１７の螺合状態を判別する手段としてもよい。このように構成した場合、押輪１７が継手本体１３の所定位置にまで螺合されていないと、凸部によりパイプ１１の内周面と内筒部１４との間に、内筒部１４の先端から基端まで隙間が形成され、シールリング３３が弾性変形せず耐圧性の低い状態となる。その結果、水圧試験を行ったとき、隙間からシールリング３３に水圧が作用してシールリング３３が弾性変形し、継手１２の漏水の原因となる。
【００５６】
・　実施形態では、シールリング３３の外径をそれぞれ内筒部１４の外径と同じ長さになるように設定したが、シールリング３３の外径は、内筒部１４の外径と全く同じに設定されなくてもよい。即ち、押輪１７が継手本体１３の所定位置にまで螺合されず、水圧等の液体による圧力が凹溝１４ａからシールリング３３に直接的に作用したとき、その圧力により弾性変形可能とするならば内筒部１４の外径と若干異なるように設定されてもよい。具体的には、シールリング３３の外径は内筒部１４の外径より最大０．３０ｍｍまで大きく形成されてもよく、この場合はシールリング３３の外周部は内筒部１４の外径より０．１５ｍｍ突出している。一方、シールリング３３の外径は内筒部１４の外径より最大０．５０ｍｍまで小さく形成されてもよく、この場合はシールリング３３の外周部は内筒部１４の外径より０．２５ｍｍ後退している。
【００５７】
・　実施形態では、継手１２と水道配管の管体とを接続して液体として水を流通させたが、継手１２を温水配管の管体と接続して湯を流通させたり、床暖房、ロードヒーティング用に油、エチレングリコール等を流通させてもよい。
【００５８】
・　パイプ１１は、合成樹脂製のものに限らず、例えば黄銅、銅等の金属製のものであってもよい。
・　押圧リング１５は、金属製のものに限らず、ポリオレフィン系、ポリウレタン系、ポリアクリル系、ポリエーテル系、ポリエステル系、ポリスチレン系等の合成樹脂製のものであってもよい。
【００５９】
次に、前記実施形態から把握できる技術的思想について以下に記載する。
・　前記締付部材は、パイプの挿入方向の後退側となる端部の内周縁に面取部が設けられていることを特徴とする請求項１から請求項４のいずれかに記載の継手。このように構成した場合、パイプの挿入時にその端面が押圧リングに引っ掛かることを抑制することができる。
【００６０】
・　前記締付部材は、３〜１０個の分割片を等間隔おきに配置した状態で接続部で接続して形成されることを特徴とする請求項１から請求項４のいずれかに記載の継手。このように構成した場合、押圧リングを均等に縮径させることができ、パイプを均一に締め付けることができる。
【００６１】
・　前記継手本体のパイプの挿入される端部の内周面には、継手本体に押輪を螺合する方向に向かうに従い縮径するテーパ面を形成し、前記締付部材の外周面を継手本体のテーパ面に接触させた状態で押輪を継手本体に螺合するに従って締付部材が縮径するように構成したことを特徴とする請求項１から請求項４のいずれかに記載の継手。このように構成した場合、押輪の継手本体に対する螺合に伴い、締付部材を確実に縮径させることができる。
【００６２】
【発明の効果】
以上詳述したように、この発明によれば、次のような効果を奏する。
請求項１に記載の発明によれば、締付部材を軽い締付力で縮径させることができ、同締付部材の縮径が不十分であることに起因する不具合を解消することができる。
【００６３】
請求項２に記載の発明によれば、請求項１に記載の発明の効果に加え、押輪の継手本体に対する螺合に伴い、締付部材を確実に縮径させることができる。
請求項３に記載の発明によれば、請求項１又は請求項２に記載の発明の効果に加え、継手本体に押輪を仮締めした状態で、パイプを継手に確実に仮止めすることができる。
【００６４】
請求項４に記載の発明によれば、請求項１又は請求項２に記載の発明の効果に加え、継手本体に押輪を仮締めするときに必要とする力を軽減することができる。
【００６５】
請求項５に記載の発明によれば、軽い締付力で縮径させることができ、縮径が不十分であることに起因する不具合を解消することができる。
【図面の簡単な説明】
【図１】第１実施形態の継手を示す分解斜視図。
【図２】（ａ）は押輪と継手本体とを螺合した状態を示す半縦断面図、（ｂ）は継手本体に押圧リングが装着された状態を示す側面図。
【図３】（ａ）は押圧リングでパイプを締め付けた状態を示す半縦断面図、（ｂ）は押圧リングでパイプを締め付けた状態を示す側面図。
【図４】第２実施形態の継手を示す分解斜視図。
【符号の説明】
１１…パイプ、１２…継手、１３…継手本体、１５…締付部材としての押圧リング、１５ａ…分割片、１５ｂ…接続部、１７…押輪、４７…締付部材に形成された第３テーパ面。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a pipe joint used for water supply piping, hot water piping, floor heating, road heating, and the like, and a fastening member for the joint.
[0002]
[Prior art]
Conventionally, this type of joint has a tubular shape, a joint body in which an inner tubular portion protrudes from the inner periphery, a tubular push ring screwed to a distal end portion of the joint body, a joint body and a push ring. And a C-ring-shaped tightening member disposed therebetween. The joint is assembled by arranging a tightening member on the distal end side of the joint main body and gently screwing the pressing ring to the distal end portion of the joint main body manually. Then, the assembled joint is assembled by connecting the base end of the joint main body to the water supply pipe, then inserting the end of the pipe into the joint main body through the inside of the press ring, and externally fitting the inner cylindrical part. Is performed.
[0003]
After the assembly, when the push ring is screwed into the joint body using a spanner or the like, the tightening member is pushed into the joint body as the push ring is tightened. Then, the diameter of the C-ring shaped fastening member is reduced, and the outer peripheral surface of the pipe is fastened. Then, the tightening member is positioned between the joint body and the push ring in a state where the push ring is firmly screwed and connected to the joint body, so that the pipe is prevented from coming off.
[0004]
[Problems to be solved by the invention]
However, in the above-mentioned conventional joint, the fastening member is made of metal, and there is a problem that the pressing ring must be fastened with a very strong force in order to bend the entirety of the fastening member to reduce its diameter. Further, the reaction force generated when the diameter of the tightening member is reduced may cause insufficient tightening of the pressing ring to the joint body, or the tightening member may bend unevenly and be reduced in diameter. In this case, the pipe is not sufficiently tightened by the tightening member, the pipe comes off from the joint, or a gap is formed between the inner peripheral surface of the pipe and the outer peripheral surface of the inner cylinder portion, and water leaks from the gap. There is also a problem that such a problem occurs.
[0005]
The present invention has been made by paying attention to the problems existing in the prior art as described above. The object is to reduce the diameter of the tightening member with a light tightening force, and to solve the problems caused by insufficient diameter reduction of the tightening member. The object of the present invention is to provide a tightening member.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the invention of the joint according to claim 1 provides a joint body having a cylindrical shape, a press ring screwed to one end of the joint body, and a joint between the joint body and the press ring. And a cylindrical tightening member disposed in the joint body, and the tightening member is reduced in diameter as the pressing ring is screwed into the joint body in a state where the end of the pipe is inserted into the joint body. A joint configured to tighten an outer surface of the pipe to prevent the pipe from falling off, wherein the tightening member includes a plurality of divided pieces and a state in which a gap is provided between each of the divided pieces. And a connecting portion for connecting to each other.
[0007]
According to a second aspect of the present invention, in the first aspect of the present invention, the fastening member is formed in a tapered shape whose outer peripheral surface is reduced in diameter in a direction in which the pressing ring is screwed into the joint body. It is characterized by having.
[0008]
According to a third aspect of the present invention, in the first or second aspect of the invention, the connecting portion connects an end of each of the divided pieces on the forward side in the pipe insertion direction with respect to the joint body. It is characterized by being.
[0009]
According to a fourth aspect of the present invention, in the first aspect or the second aspect, the connecting portion connects an end portion of each of the divided pieces on a retreating side in a pipe insertion direction with respect to the joint body. It is characterized by being.
[0010]
According to a fifth aspect of the present invention, there is provided a joint tightening member arranged between a tubular joint body constituting a joint to which a pipe can be connected, and a pressing ring screwed to one end of the joint body. In the state where the end of the pipe is inserted into the joint body, the diameter is reduced as the push ring is screwed into the joint body, and the pipe is prevented from coming off by tightening the outer surface of the pipe. A fastening member for a joint, comprising: a plurality of divided pieces; and a connecting portion for connecting the divided pieces to each other in a state where a gap is provided between each of the divided pieces. It is a feature.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
[0012]
As shown in FIGS. 1 to 3A and 3B, a joint 12 configured to be connectable with a pipe 11 includes a substantially cylindrical joint body 13 and a cylindrical pressing ring 15 as a fastening member. And a pressing wheel 17 composed of a nut. A substantially cylindrical inner cylinder portion 14 is provided inside the joint body 13. An annular washer 16 is interposed between the pressing ring 15 and the pressing wheel 17. The joint body 13, the inner cylinder 14, the pressing ring 15, the washer 16, and the pressing ring 17 are each formed of a metal material such as an alloy (brass, bronze, etc.). The pipe 11 is formed in a cylindrical shape from a synthetic resin such as polyethylene and polybutene.
[0013]
First, the joint body 13 will be described.
A first external thread portion 18 is threaded on the outer peripheral surface of the proximal end portion of the joint body 13 so that it can be screwed into a pipe (not shown) such as a water supply pipe. A second external thread 27 is threaded on the outer peripheral surface of the distal end of the joint body 13. Further, an abutment surface 19 is provided in an annular shape on the inner peripheral surface at the central portion in the longitudinal direction of the joint body 13 so as to be orthogonal to the axis of the joint body 13. In the joint body 13, an introduction path 20 through which the transport liquid can flow is formed on the base end side (right end side in FIG. 2A) of the contact surface 19 with the contact surface 19 as a boundary. A first female screw portion 21 is threaded on the tip side (the right end side in FIG. 2) from the surface 19.
[0014]
The first female screw portion 21 is formed so as to be screwable with a third male screw portion 30 threaded at a base end of the inner cylindrical portion 14 formed separately from the joint body 13. Then, the third male screw portion 30 is screwed into the first female screw portion 21 until the base end surface of the inner cylindrical portion 14 comes into contact with the abutting surface 19, so that the inner cylindrical portion 14 is threadably connected to the joint body 13. Have been. The first female screw portion 21 and the third male screw portion 30 are bonded by an anaerobic adhesive.
[0015]
On the outer peripheral edge of the distal end of the inner cylindrical portion 14, a second tapered surface 31 whose diameter decreases toward the distal end of the inner cylindrical portion 14 is formed, and on the outer peripheral surface closer to the base end than the second tapered surface 31, An accommodation groove 32 is formed to be recessed over the entire outer periphery of the inner cylindrical portion 14. Four sealing rings 33 as sealing members made of a rubber material and having a circular cross section are fitted in the housing grooves 32. The outer diameter of each of these seal rings 33 is set to the same length as the outer diameter of the inner cylindrical portion 14, and the thickness of the seal ring 33 is set to be the same as the depth of the accommodation groove 32.
[0016]
The outer peripheral surface of the inner cylindrical portion 14 extends spirally from the base end of the inner cylindrical portion 14 to the accommodation groove 32 along the circumferential direction and is continuous with the accommodation groove 32. A concave groove 14a spirally extending to 31 is provided as a concave portion. That is, the concave groove 14a is formed so as to extend from the distal end to the proximal end of the inner cylindrical portion 14 across the seal ring 33 fitted in the housing groove 32.
[0017]
An annular insertion space 37 for inserting the pipe 11 into the joint main body 13 is formed between the inner peripheral surface on the distal end side of the joint main body 13 and the outer peripheral surface of the inner cylindrical portion 14. An inclined wall 38 whose diameter is reduced toward the contact surface 19 is formed in the inner part of the insertion space 37, and an annular reduced diameter portion 39 is formed on the contact surface 19 side of the inclined wall 38. Have been. An O-ring 40 made of a rubber material and having a circular cross section is fitted to the reduced diameter portion 39.
[0018]
At a substantially central portion of the joint main body 13, a single through hole 23 having a substantially circular planar shape is formed. As shown in FIG. 1, a substantially cylindrical collar 24 made of a synthetic resin such as polyacetal is fitted into the through hole 23. A substantially cylindrical shaft 25 made of synthetic resin such as polyacetal is fitted into the collar 24. The shaft 25 is configured to be movable in the direction perpendicular to the axis of the joint body 13 in the through hole 23 according to the inserted state of the pipe 11. That is, if the pipe 11 is not inserted, the shaft 25 is at a position where its outer end is immersed in the through hole 23 and its inner end is projected into the joint body 13 from the through hole 23. Conversely, if the pipe 11 is inserted, the outer end of the shaft 25 projects outward from the through hole 23 and the inner end of the shaft 25 is at a position where it is immersed in the through hole 23.
[0019]
Next, the pressing wheel 17 will be described.
On the inner peripheral surface of the base end portion of the press ring 17, a second female screw portion 41 which can be screwed with the second male screw portion 27 of the joint main body 13 is threaded. A locking surface 44 is formed on the distal end side of the second female screw portion 41 in an annular shape so as to be orthogonal to the axis of the pressing wheel 17. An accommodation recess 45 is formed in the inner peripheral surface of the distal end portion of the pressing ring 17 over the entire circumference. Into the accommodation recess 45, a slip-out preventing ring 46 made of a rubber material and having a circular cross section for preventing the pipe 11 from slipping out of the joint 12 is fitted.
[0020]
Next, the pressing ring 15 will be described.
On the inner peripheral surface on the distal end side of the joint main body 13, a first tapered surface 29 that is reduced in diameter in a direction in which the pressing ring 17 is screwed to the joint main body 13, that is, in a direction from the distal end side to the inside of the joint main body 13. Is formed. The outer peripheral surface of the pressing ring 15 is a third tapered surface 47 corresponding to the first tapered surface 29 of the joint main body 13, the diameter of which decreases as the pressing ring 17 is screwed into the joint main body 13. The pressing ring 15 is disposed between the joint body 13 and the pressing wheel 17.
[0021]
In this state, the washer 16 is interposed between the pressing ring 15 and the locking surface 44 of the pressing ring 17. An uneven surface for preventing the pipe 11 from falling into the joint body 13 is formed on the entire inner peripheral surface of the pressing ring 15. In addition, a chamfered portion 15c is provided on an inner peripheral edge of the distal end portion of the pressing ring 15, which is a retreating side in the inserting direction of the pipe 11, that is, an inlet side of the pipe 11.
[0022]
The pressing ring 15 is formed of four wedge-shaped divided pieces 15a, and a connecting portion 15b that connects each of the divided pieces 15a. The connecting portion 15b connects the base ends of the divided pieces 15a on the forward side in the insertion direction of the pipe 11 respectively. The pressing ring 15 is formed at the boundary between the split piece 15a and the connecting portion 15b, or at the connecting portion 15b itself, or the connecting portion 15b is broken and the split piece 15a is cut off. The notch between 15a, that is, the gap is reduced, so that the diameter can be reduced.
[0023]
The pressing ring 15 is manufactured by forming four notches extending in the axial direction at equal intervals in the circumferential direction on the peripheral wall of the metal cylinder. In other words, when the peripheral wall of the metal cylinder is cut out, by leaving one very small portion of the peripheral wall without cutting one edge of the metal cylinder, the one remaining portion is sandwiched between the connection portion 15b and the notch. The divided peripheral wall portion is configured as a divided piece 15a.
[0024]
As the length of the connecting portion 15b in the axial direction becomes shorter, bending or breaking at the connecting portion 15b is more likely to occur, so that the diameter of the pressing ring 15 is more easily reduced. However, if the length is excessively short, it becomes difficult to perform the cutting operation, and the strength of the strength may be insufficient, so that each of the divided pieces 15a may be cut off when assembling to the joint body 13 or the like. If the length of the connecting portion 15b in the axial direction is excessively long, the connecting portion 15b does not bend or break, and the pressing ring 15 may not even be reduced in diameter. Therefore, the axial length of the connecting portion 15b is short enough to easily reduce the diameter of the pressing ring 15 and long enough to easily perform the cutting operation and maintain the desired strength. preferable. Specifically, the length of the connection portion 15b in the axial direction is preferably 0.05 to 2.0 mm, more preferably 0.1 to 1.0 mm, and still more preferably 0.2 to 0.5 mm. is there.
[0025]
In addition, the wider the gap between the divided pieces 15a, the larger the diameter reduction ratio of the pressing ring 15 and the easier the cutting operation. However, if the gap is excessively wide, when the outer peripheral surface of the pipe 11 is tightened with the pressing ring 15 having a reduced diameter, a large gap is formed between the divided pieces 15a. In this state, each divided piece 15a may be displaced from the pipe 11 due to shock or vibration applied from the outside, rotation or movement of the pipe 11 with respect to the joint 12, or the like. As a result, the outer peripheral surface of the pipe 11 cannot be uniformly tightened by each of the divided pieces 15a, and the tightening force of the tightening member such as a reduction in resistance to pulling out of the pipe 11 and a reduction in water sealing performance is not sufficient. There is a possibility that a defect due to the sufficient condition may occur. On the other hand, if the gap between the divided pieces 15a is excessively narrow, the pressing ring 15 cannot be reduced in diameter until the outer peripheral surface of the pipe 11 is sufficiently tightened, and the pressing ring 15 may not be tightly closed. There is a possibility that a problem may occur due to insufficient fastening force of the attachment member. Accordingly, the gap between the divided pieces 15a is narrow enough to reduce the diameter until the outer peripheral surface of the pipe 11 is sufficiently tightened, and there is no gap between the divided pieces 15a in the reduced diameter state, or It is preferable that the width is slightly widened to some extent.
[0026]
Next, the operation of the joint 12 configured as described above will be described.
Now, the work of assembling the joint 12 is performed as follows. That is, as shown in FIGS. 2A and 2B, first, with the pressing ring 15 and the washer 16 arranged on the distal end side of the joint body 13, the pressing ring 17 is loosened manually on the joint body 13. Screwed together. Next, the first male screw portion 18 of the joint body 13 is connected to a tube (not shown). Then, the end of the pipe 11 is inserted into the insertion space 37 in the joint main body 13 via the inside of the press ring 17, and the end of the pipe 11 is fitted to the inner cylindrical portion 14.
[0027]
As shown in FIGS. 3A and 3B, when the end of the pipe 11 is inserted into the insertion space 37, the end of the pipe 11 is pressed against the inner end of the shaft 25, and the shaft 25 is The joint body 13 is moved toward the outer peripheral surface. As a result, the outer end of the shaft 25 is displaced from a state of immersion in the through hole 23 to a state of protruding outward. Therefore, the insertion depth of the end of the pipe 11 into the insertion space 37 of the joint body 13 can be visually recognized.
[0028]
Thereafter, the pressing wheel 17 is firmly tightened to the joint body 13 by hand and screwed in a temporarily tightened state. At this time, as the pressing ring 15 is tightened, the pressing ring 15 is pushed into the inside of the joint body 13 while sliding the third tapered surface 47 into contact with the first tapered surface 29. Then, due to the sliding contact of the third tapered surface 47 with the first tapered surface 29, each of the divided pieces 15a rotates around the connecting portion 15b in a direction to gradually shrink the gap therebetween from the distal end side of the pressing ring 15. Then, the pressing ring 15 starts to be reduced in diameter. When the force for reducing the diameter of the pressing ring 15 exceeds the strength of the connecting portion 15b, each connecting portion 15b is broken, and each divided piece 15a is separated.
[0029]
Each of the divided pieces 15a separated when the pressing ring 17 is temporarily tightened functions as a wedge driven between the joint body 13 and the pipe 11. In other words, the pressing ring 15 mainly requires a force for pushing the separated divided pieces 15a between the joint body 13 and the pipe 11, and the entirety of the tightening member is bent like a conventional tightening member. No large force is required to reduce the diameter. The force for pushing each of the divided pieces 15a between the joint body 13 and the pipe 11 is a force sufficient even by manual work. Therefore, the work of temporarily tightening the pressing wheel 17 can be performed with a small force.
[0030]
Thereafter, as the pressing ring 17 is tightened, the divided pieces 15 a are each applied with a uniform force via the washer 16, and are pushed into the inside of the joint body 13. The pipe 11 into which the four divided pieces 15a have been pushed into the joint body 13 is tightened on the outer peripheral surface by an equal force by each divided piece 15a, and is temporarily fixed to the joint 12. In this state, position adjustment, arrangement adjustment, and the like of the pipe 11 in the room are performed. After the position adjustment, the arrangement adjustment, and the like of the pipe 11 are performed, the pressing ring 17 is tightly fastened to the joint body 13 using a tool such as a spanner, and is screwed in a fully tightened state.
[0031]
As shown in FIG. 3A, when the pressing ring 17 is fully tightened to the joint body 13, the base end of each split piece 15a reaches the innermost portion of the joint body 13, and each split piece 15a Are positioned and fixed between the joint body 13 and the pressing wheel 17. In this state, as shown in FIG. 3B, each of the divided pieces 15a has a substantially perfect circular shape as a whole, and the inner surface thereof is uniformly pressed against the outer peripheral surface of the pipe 11 so that the pipe 15 is pressed. 11 is firmly tightened. Further, in this state, since there is almost no gap between the divided pieces 15a, the divided pieces 15a regulate movement of each other, and press each inner surface against the outer peripheral surface of the pipe 11 to remove unevenness of the inner surface. By cutting into the outer peripheral surface of the joint 11, the pipe 11 is prevented from coming out of the joint 12. As a result, the pipe 11 is firmly prevented from falling into the joint body 13 by each of the divided pieces 15a positioned between the joint body 13 and the pressing wheel 17. Further, each of the divided pieces 15a functions as a wedge, and exerts a strong resistance to the pulling force of the pipe 11.
[0032]
On the other hand, the pipe 11 fastened by each of the divided pieces 15a is pressed against the outer peripheral surface of the inner cylindrical portion 14 and enters the accommodation groove 32 and the concave groove 14a. The pipe 11 that has entered the accommodation groove 32 is pressed against each seal ring 33, and as a result, the seal ring 33 is elastically deformed by the pressure contact, and comes into surface contact with each other, and at the same time, the inner surface of the accommodation groove 32 and the inner periphery of the pipe 11. Surface contact is also made with the surface. The seal ring 33 exhibits a function of sealing water between the inner peripheral surface of the pipe 11 and the outer peripheral surface of the inner cylindrical portion 14, and the pressure resistance of the seal ring 33 against water pressure is improved.
[0033]
After the assembly work of the joint 12 is performed as described above, a predetermined water pressure is applied to the joint 12 to perform a hydraulic test. In the same water pressure test, it is confirmed whether or not the pipe 11 is sufficiently tightened by the respective divided pieces 15a. That is, when the pipe 11 is not sufficiently fastened, the inner peripheral surface of the pipe 11 comes into light contact with each of the seal rings 33 provided on the outer peripheral surface of the inner cylindrical portion 14. When a water pressure test is performed in this state, water leaked from between the seal ring 33 and the pipe 11 passes through the concave groove 14 a and flows out of the connection portion between the joint body 13 and the pressing ring 17 via the insertion space 37. . As a result, the operator confirms that the pipe 11 has not been sufficiently tightened by the divided pieces 15a, and the pressing ring 17 is further tightened.
[0034]
According to the first embodiment described in detail above, the following effects are exhibited.
The pressing ring 15 for tightening and stopping the pipe 11 is formed of four wedge-shaped divided pieces 15a and connecting portions 15b connecting the divided pieces 15a, respectively. When the pressing ring 17 is screwed into the joint body 13 and tightened to reduce the diameter of the pressing ring 15, each of the divided pieces 15a is cut off by breaking the connecting portion 15b. For this reason, a force for pushing each split piece 15a into the inner part of the joint main body 13 is mainly required, and it is not necessary to apply a force for bending the entire pressing ring 15 to reduce the diameter. Therefore, the tightening force of the pressing wheel 17 can be reduced, and the diameter of the pressing ring 15 can be easily reduced by the light tightening force.
[0035]
Also, each of the divided pieces 15a that are cut off by breaking the connecting portion 15b of the pressing ring 15 functions as a wedge that is driven between the inner peripheral surface of the joint body 13 and the outer peripheral surface of the pipe 11. . Then, each of the divided pieces 15a uniformly presses the inner surface thereof to the outer peripheral surface of the pipe 11 while maintaining a substantially perfect circular shape as a whole. For this reason, the pipe 11 is firmly tightened, a strong resistance against pulling out is exerted while the removal is restricted, and a water sealing function between the inner peripheral surface of the pipe 11 and the outer peripheral surface of the inner cylindrical portion 14 is provided. Is improved. Therefore, it is possible to solve the problem caused by insufficient diameter reduction of the pressing ring 15.
[0036]
The connection portion 15b is disposed at the base end of the pressing ring 15 on the forward side in the insertion direction of the pipe 11. For this reason, when the pipe 11 is inserted, even if the pipe 11 comes into contact with the pressing ring 15, the divided piece 15a slightly moves around the connection portion 15b, and the opening diameter is enlarged, so that the pipe 11 is caught at the time of insertion. Can be suppressed.
[0037]
Also, since the connecting portion 15b is disposed at the base end of the pressing ring 15, when the pressing ring 17 is temporarily tightened, a force for reducing the diameter of the pressing ring 15 is applied to the connecting portion 15b quickly, and the connection is made. The part 15b is rapidly broken. For this reason, each of the divided pieces 15a can evenly bring the respective inner peripheral surfaces into contact with the outer peripheral surface of the pipe 11, and can tighten them. Therefore, the pipe 11 can be securely temporarily fixed to the joint 12 in a state where the pressing ring 17 is temporarily fastened to the joint main body 13.
[0038]
A chamfered portion 15c is provided on the inner peripheral edge of the distal end of the pressing ring 15. The chamfered portion 15c makes it difficult for the end face of the pipe 11 to come into contact with the pressing ring 15 when the pipe 11 is inserted, and at the same time, allows the force to flow off at the time of contact, so that the pipe 11 can be easily inserted.
[0039]
Also, as shown in FIG. 3B, in a state where the pipe 11 is tightened, each of the divided pieces 15a has a substantially perfect circular shape as a whole, and a gap is hardly formed therebetween. Have been. Therefore, even when water is leaking from the inside of the joint 12 due to, for example, application of excessive water pressure, the water can be sealed with the pressing ring 15.
[0040]
(2nd Embodiment)
Hereinafter, a second embodiment of the present invention will be described in detail with reference to the drawings. The description of the second embodiment will focus on the differences from the first embodiment.
[0041]
As shown in FIG. 4, the pressing ring 15 is formed of four wedge-shaped divided pieces 15a, and a connecting portion 15b that connects each of the divided pieces 15a. The connecting portion 15b connects the distal ends of the divided pieces 15a on the retreat side in the insertion direction of the pipe 11. Therefore, each connecting portion 15b is thicker than that of the first embodiment, and it is possible to prevent the connecting portion 15b from breaking when an unexpected force is applied or the like. Can be.
[0042]
Now, the operation of assembling the joint 12 of the second embodiment is performed in the same manner as in the first embodiment until the end of the pipe 11 is inserted into the insertion space 37 in the joint main body 13. 17 is manually tightened tightly and screwed in a temporarily tightened state. When the pressing ring 17 is temporarily tightened, the pressing ring 15 is pushed into the inside of the joint body 13 while sliding the third tapered surface 47 against the first tapered surface 29 as the pressing ring 17 is tightened. Then, due to the sliding contact of the third tapered surface 47 with the first tapered surface 29, each of the divided pieces 15a turns around the connection portion 15b in a direction to gradually shrink the gap between them from the base end side of the pressing ring 15. Be moved. Further, a force for reducing the diameter of the distal end portion of the pressing ring 15 is applied to each connecting portion 15b, and each connecting portion 15b is bent or bent, so that the pressing ring 15 starts to be reduced in diameter. Then, the pipe 11 is temporarily fixed to the joint 12 with a light force by bringing the base end of the inner peripheral surface of each of the divided pieces 15a into contact with the outer peripheral surface.
[0043]
Then, after the position adjustment, arrangement adjustment, and the like of the pipe 11 in the room are performed, the press ring 17 is firmly tightened to the joint body 13 using a tool such as a spanner, so that a final tightening state is obtained. When the pressing ring 17 is fully tightened, the force for reducing the diameter of the pressing ring 15 exceeds the strength of the connecting portion 15b, so that each connecting portion 15b is broken and each divided piece 15a is separated. The separated pieces 15a are positioned and fixed between the joint body 13 and the pressing ring 17 when the base end reaches the innermost part of the joint body 13 while uniformly tightening the outer peripheral surface of the pipe 11 respectively. Is done. Then, the pipe 11 uniformly pressed by the divided pieces 15a having a substantially perfect circular shape as a whole is firmly tightened, and the pipe 11 is prevented from coming out of the joint 12.
[0044]
According to the second embodiment described in detail above, the following effects are exhibited.
-The press ring 15 of the joint 12 of the second embodiment is arranged at the distal end of the press ring 15 whose connection portion 15b is on the retreat side in the insertion direction of the pipe 11. The connecting portion 15b does not break when the pressing ring 17 is temporarily tightened, but breaks when the pressing ring 17 is fully tightened. That is, when the pressing ring 17 is manually screwed into the joint body 13, the force mainly required to reduce the diameter of the pressing ring 15 is a force for rotating the divided pieces 15 a around the respective connection portions 15 b. It is. Therefore, compared to the first embodiment, no force is required to break the connection portion 15b, and the force applied during manual work can be reduced accordingly. Therefore, the force required when temporarily tightening the pressing wheel 17 to the joint body 13 can be reduced.
[0045]
Also, since the connecting portion 15b is disposed at the distal end of the pressing ring 15, even when the pipe 11 is hooked on the pressing ring 15 when the pipe 11 is inserted, the opening diameter of the distal end of the pressing ring 15 is maintained. be able to. Therefore, it is possible to suppress the occurrence of problems such as a decrease in the opening diameter when the pipe 11 is inserted.
[0046]
When the connecting portion 15b is disposed at the distal end of the pressing ring 15, the thickness thereof is thicker than when the connecting portion 15b is disposed at the base end of the pressing ring 15. Therefore, the strength of the connecting portion 15b of the pressing ring 15 can be improved.
[0047]
In addition, the divided pieces 15a are not cut off while the pressing ring 17 is temporarily fastened to the joint body 13, and the pipe 11 is temporarily fixed with a light force. For this reason, in a case where the pipe 11 is insufficiently inserted, a connection is incorrect, or the like, the pipe 11 can be easily pulled out and reinserted, and the work of inserting and removing the pipe 11 can be simplified.
[0048]
The above-described embodiment can be modified as follows.
In the embodiment, the number of the divided pieces 15a and the number of the connection portions 15b are each four, but the number is not limited thereto, and may be two or three, or five or more. The smaller the number of the divided pieces, the wider the gap between the divided pieces, so that the gap is easily narrowed, and the tightening force can be reduced. However, if the gap is excessively large, the sealing performance against water deteriorates. Resulting in. On the other hand, as the number of the divided pieces increases, the gap between the divided pieces becomes narrower, and the sealing performance against water is improved, but the cutting work becomes difficult and the tightening force increases. Therefore, it is preferable that the number of the divided pieces is such that the tightening force can be reduced while maintaining the sealing performance against water, and the cutting operation can be easily performed. Specifically, the number of divided pieces is preferably 3 to 10, more preferably 4 to 6. In this case, it is preferable that the divided pieces are arranged at regular intervals. By arranging the divided pieces at equal intervals in this manner, the pressing ring 15 can be reduced in diameter uniformly while maintaining a substantially perfect circular shape, and the outer peripheral surface of the pipe can be uniformly tightened.
[0049]
In the embodiment, the connection portion 15b is provided at the base end of the pressing ring 15, but is not limited thereto, and may be provided at, for example, the front end or the intermediate portion of the pressing ring 15. Further, the number of the connection portions 15b is not limited to one provided between the divided pieces 15a, and two or more connection portions may be provided.
[0050]
In the embodiment, the divided piece 15a and the connecting portion 15b are integrally formed by performing a cutting process on the metal cylinder. However, the present invention is not limited to this. The pressing ring 15 may be used. For example, a plurality of divided pieces 15a may be formed, and these divided pieces 15a may be connected to each other by a bonding means such as an adhesive resin, an adhesive, an adhesive tape, or solder to form the pressing ring 15. In this case, the portion formed by the joining means becomes the connecting portion 15b.
[0051]
In the embodiment, the joint body 13 is provided with the first tapered surface 29, and the pressing ring 15 is provided with the third tapered surface 47 so as to reduce the diameter of the pressing ring 15. However, the present invention is not limited to this. For example, a tapered surface may be provided on the inner peripheral surface of the pressing wheel 17 and a corresponding tapered surface may be provided on the outer peripheral surface of the pressing ring 15. That is, a female screw is threaded on the inner peripheral surface of the joint body 13 as an internal screw, and a male screw is threaded on the outer peripheral surface of the pressing ring 17 as an external screw that can be screwed with the internal screw. The inner peripheral surface of the pressing ring 17 is formed with a tapered surface that increases in diameter in the screwing direction of the pressing ring 17, and the outer peripheral surface of the pressing ring 15 is correspondingly formed in the inner peripheral surface of the pressing ring 17 in the screwing direction of the pressing ring 17. The diameter may be increased. Also in this case, the diameter of the pressing ring 15 can be reduced as the pressing ring 17 is screwed.
[0052]
In the embodiment, four seal rings 33 are provided, but any one to three or five or more seal rings 33 may be fitted into the accommodation groove 32. At this time, the size of the accommodation groove 32 may be changed in accordance with the number of the seal rings 33 used. Alternatively, a seal ring having a rectangular cross section made of a rubber material and having a thickness set to be the same as or slightly different from the depth of the accommodation groove 32 may be used.
[0053]
In the embodiment, the inner cylinder portion 14 and the joint body 13 are formed so as to be attachable by a screwing relationship. However, the first female thread portion 21 of the joint body 13 and the third male thread portion 30 of the inner cylinder portion 14 are omitted. The base end of the inner cylinder portion 14 and the joint body 13 may be configured to be attachable in a fitting relationship.
[0054]
In the embodiment, the inner cylinder portion 14 and the joint body 13 are configured separately, but the inner cylinder portion 14 may be formed integrally with the joint body 13.
In the embodiment, the concave groove 14 a is formed to extend helically along the circumferential direction of the inner cylindrical portion 14. However, the concave groove 14 a is formed in the longitudinal direction of the inner cylindrical portion 14 so as to communicate with the accommodation groove 32. May be formed so as to extend in a linear or wavy shape along the line.
[0055]
In the embodiment, the concave groove 14 a is formed in the inner cylinder portion 14, but a convex portion may be formed on the outer surface of the inner cylinder portion 14, and the convex portion may determine the screwing state of the pressing ring 17. In such a configuration, if the press ring 17 is not screwed to a predetermined position of the joint body 13, the protrusion of the distal end of the inner cylindrical portion 14 is provided between the inner peripheral surface of the pipe 11 and the inner cylindrical portion 14. A gap is formed from to the base end, so that the seal ring 33 is not elastically deformed and has a low pressure resistance. As a result, when a water pressure test is performed, water pressure acts on the seal ring 33 from a gap to elastically deform the seal ring 33, which causes leakage of the joint 12.
[0056]
In the embodiment, the outer diameter of the seal ring 33 is set to be the same length as the outer diameter of the inner cylindrical portion 14, but the outer diameter of the seal ring 33 is exactly the same as the outer diameter of the inner cylindrical portion 14. May not be set. In other words, if the pressing ring 17 is not screwed to a predetermined position of the joint body 13 and a pressure by a liquid such as water pressure directly acts on the seal ring 33 from the concave groove 14a, the pressure can be elastically deformed by the pressure. It may be set so as to be slightly different from the outer diameter of the inner cylindrical portion 14. Specifically, the outer diameter of the seal ring 33 may be formed up to a maximum of 0.30 mm larger than the outer diameter of the inner cylindrical portion 14, and in this case, the outer peripheral portion of the seal ring 33 is larger than the outer diameter of the inner cylindrical portion 14. It protrudes by 0.15 mm. On the other hand, the outer diameter of the seal ring 33 may be formed to be smaller than the outer diameter of the inner cylindrical portion 14 by a maximum of 0.50 mm. In this case, the outer peripheral portion of the seal ring 33 is 0.25 mm larger than the outer diameter of the inner cylindrical portion 14. Retreating.
[0057]
In the embodiment, water is circulated as a liquid by connecting the joint 12 to a pipe of a water supply pipe. However, the joint 12 is connected to a pipe of a hot water pipe to circulate hot water, floor heating, and road heating. For example, oil, ethylene glycol, etc. may be distributed.
[0058]
The pipe 11 is not limited to the one made of synthetic resin, but may be made of metal such as brass and copper.
The press ring 15 is not limited to a metal ring, but may be a synthetic resin such as a polyolefin, polyurethane, polyacryl, polyether, polyester, or polystyrene.
[0059]
Next, technical ideas that can be grasped from the embodiment will be described below.
The joint according to any one of claims 1 to 4, wherein the fastening member is provided with a chamfered portion at an inner peripheral edge of an end portion on a retreat side in a pipe insertion direction. With this configuration, it is possible to prevent the end face from being caught on the pressing ring when the pipe is inserted.
[0060]
5. The device according to claim 1, wherein the tightening member is formed by connecting 3 to 10 divided pieces at a connection portion at equal intervals. 6. Fittings. With such a configuration, the pressing ring can be uniformly reduced in diameter, and the pipe can be uniformly tightened.
[0061]
A tapered surface is formed on the inner peripheral surface of the end of the joint body into which the pipe is inserted, the taper surface being reduced in diameter in the direction in which the push ring is screwed into the joint body. The joint according to any one of claims 1 to 4, wherein the tightening member is configured to be reduced in diameter as the press ring is screwed into the joint main body in a state of being in contact with the tapered surface of the joint. With this configuration, the diameter of the tightening member can be reliably reduced as the press ring is screwed into the joint body.
[0062]
【The invention's effect】
As described above, according to the present invention, the following effects can be obtained.
According to the first aspect of the present invention, it is possible to reduce the diameter of the fastening member with a small tightening force, and it is possible to solve a problem caused by insufficient diameter reduction of the fastening member. .
[0063]
According to the second aspect of the present invention, in addition to the effect of the first aspect, the diameter of the tightening member can be reliably reduced as the press ring is screwed into the joint body.
According to the invention described in claim 3, in addition to the effects of the invention described in claim 1 or 2, the pipe can be securely temporarily fixed to the joint while the push ring is temporarily fastened to the joint body. .
[0064]
According to the fourth aspect of the invention, in addition to the effects of the first or second aspect of the invention, it is possible to reduce the force required for temporarily tightening the pressing ring to the joint body.
[0065]
According to the fifth aspect of the present invention, the diameter can be reduced by a light tightening force, and a problem caused by insufficient diameter reduction can be solved.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing a joint according to a first embodiment.
2A is a semi-longitudinal sectional view showing a state in which a press wheel and a joint body are screwed together, and FIG. 2B is a side view showing a state in which a pressing ring is attached to the joint body.
FIG. 3A is a semi-longitudinal sectional view showing a state where a pipe is fastened by a pressing ring, and FIG. 3B is a side view showing a state where the pipe is fastened by a pressing ring.
FIG. 4 is an exploded perspective view showing a joint according to a second embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Pipe, 12 ... Joint, 13 ... Joint main body, 15 ... Pressing ring as a fastening member, 15a ... Split piece, 15b ... Connection part, 17 ... Pressing ring, 47 ... Third tapered surface formed on the fastening member .

Claims

A tubular joint body, a push ring screwed to one end of the joint body, and a tubular tightening member disposed between the joint body and the push ring are provided inside the joint body. As the push ring is screwed into the joint body in a state where the end of the pipe is inserted, the diameter of the tightening member is reduced, and the outer surface of the pipe is tightened to prevent the pipe from coming off. So,
The joint, wherein the fastening member is formed of a plurality of divided pieces and a connecting portion for connecting the divided pieces to each other with a gap provided between them.

2. The joint according to claim 1, wherein the fastening member is formed in a tapered shape whose outer peripheral surface is reduced in diameter in a direction in which the pressing ring is screwed into the joint body. 3.

3. The joint according to claim 1, wherein the connection portion connects an end of each of the divided pieces on a forward side in a pipe insertion direction with respect to the joint body. 4.

3. The joint according to claim 1, wherein the connecting portion connects an end of each of the divided pieces on a retreat side in a pipe insertion direction with respect to the joint main body. 4.

A pipe-shaped joint main body constituting a joint connectable with a pipe, and a pressing ring screwed to one end of the joint main body are arranged between the joint main body, and the end of the pipe is inserted into the joint main body. A tightening member for a joint configured to reduce the diameter as the push ring is screwed into the joint body in the state, and to prevent the pipe from coming off by tightening the outer surface of the pipe,
A fastening member for a joint, comprising: a plurality of divided pieces; and a connecting portion for connecting the divided pieces to each other in a state where a gap is provided between the divided pieces.