JP4625855B2

JP4625855B2 - Pipe fitting

Info

Publication number: JP4625855B2
Application number: JP2008202357A
Authority: JP
Inventors: 一清手嶋; 昭宏増田; 岳寛中村; 真照山田; 貴之岸本; 敏行福元; 良今西
Original assignee: Nippon Pillar Packing Co Ltd
Current assignee: Nippon Pillar Packing Co Ltd
Priority date: 2008-08-05
Filing date: 2008-08-05
Publication date: 2011-02-02
Anticipated expiration: 2028-08-05
Also published as: JP2010038257A

Description

本発明は、流体移送路としての合成樹脂製のチューブ同士、又は該チューブとポンプ，バルブ，フィルタ等の流体機器を接続する合成樹脂製の管継手に関し、特に、半導体や液晶表示パネル製造，医療・医薬品製造，食品加工、化学工業の各種技術分野で取り扱われる高純度液や超純水，薬液等の配管にも使用可能な合成樹脂製の管継手に関するものである。 The present invention relates to synthetic resin tubes as fluid transfer paths, or synthetic resin pipe joints that connect the tubes and fluid devices such as pumps, valves, filters, etc., in particular, semiconductor and liquid crystal display panel manufacturing, medical -This relates to pipe joints made of synthetic resin that can be used for piping of high-purity liquid, ultrapure water, chemical liquid, etc., handled in various technical fields of pharmaceutical manufacturing, food processing, and chemical industry.

この種の管継手としては、特許文献１において開示されるチューブ継手が知られている。即ち、合成樹脂製のチューブ１を合成樹脂製の継手本体４のインナ筒部５に強制的に押し込むか、又は特許文献１の図２に示されるように、予めチューブ端部２を拡径させてからインナ筒部に嵌め込むかする。それから、予めチューブに外嵌されている合成樹脂製の袋ナット６を継手本体に螺合させることにより、チューブの拡径付け根部分２ａを袋ナットのエッジ部６ａでインナ筒部の尖端５Ａに強く押圧し、チューブとインナ筒部との間をシールする構造である。 As this type of pipe joint, a tube joint disclosed in Patent Document 1 is known. That is, the tube 1 made of synthetic resin is forcibly pushed into the inner tube portion 5 of the joint body 4 made of synthetic resin, or the tube end portion 2 is expanded in advance as shown in FIG. After that, fit it into the inner tube. Then, a synthetic resin cap nut 6 fitted in advance to the tube is screwed into the joint body, so that the enlarged diameter root portion 2a of the tube is strongly attached to the tip 5A of the inner cylinder portion by the edge portion 6a of the cap nut. It is a structure which presses and seals between a tube and an inner cylinder part.

上述の構造と同様なものとしては、特許文献２の図８，図９において開示されたものや、特許文献３の図６において開示された管継手が知られている。これらのように、チューブの先端を拡径（フレア）させて継手本体に嵌めてナット止めする継手構造は、特許文献２の図５や特許文献３の図４等において開示される構造、即ち、専用部品のインナーリングに拡径外嵌されているチューブ端を継手本体の筒状受口に内嵌させてナット止めする３部品構造の管継手に比べて、継手本体とナット部材という少ない部品点数（２点）で経済的に管継手を構成しながらも良好なシール機能が得られる利点がある。 As the structure similar to the above-described structure, those disclosed in FIGS. 8 and 9 of Patent Document 2 and the pipe joint disclosed in FIG. 6 of Patent Document 3 are known. As described above, the joint structure in which the tip of the tube is expanded (flared), fitted into the joint body, and fastened with a nut is the structure disclosed in FIG. 5 of Patent Document 2, FIG. 4 of Patent Document 3, and the like, Compared to a three-part tube fitting that has a tube end fitted to the inner ring of a dedicated part with an expanded outer diameter fitted into the tubular receiving port of the fitting body and is fastened with a nut, the joint body and the nut member have fewer parts (2 points) is advantageous in that a good sealing function can be obtained while economically constituting a pipe joint.

ところが、上述のように２点部品で成る従来の管継手では、チューブ端を拡径させて強固に嵌合させ、かつ、拡径根元部分をナット部材で締め付けているが、その締め付けはシール機能を出すためのものであるためか、チューブを継手本体から引き抜こうとする力には比較的弱いという傾向があった。特に、１００℃以上の高温流体を扱うべく管継手がフッ素樹脂等の大きな膨張係数を有する合成樹脂で形成されている場合には、その問題がより顕著化されてしまう。 However, in the conventional pipe joint composed of two parts as described above, the end of the tube is expanded and firmly fitted, and the base of the expanded diameter is tightened with a nut member. There is a tendency that it is relatively weak against the force of pulling out the tube from the joint body because it is for the purpose of removing the tube. In particular, when the pipe joint is formed of a synthetic resin having a large expansion coefficient such as a fluororesin so as to handle a high-temperature fluid of 100 ° C. or higher, the problem becomes more prominent.

そこで、特許文献４にて開示されるように、チューブ拡径部とナット部材との間にＣ字状の割リングをチューブ拡径部の周溝に嵌る状態で介装させる構造の耐引き抜き手段を設けることにより、シール機能だけでなくチューブの引き抜きに対しても強い管継手を得ることが知られている。しかしながら、その特許文献４で開示される管継手では、部品点数が２部品から１部品（割リング）増えて３部品となることから、元々有していた経済性の良さが損われてしまうという新たな問題が生じる。従って、継手本体とナット部材との２点で成る管継手を、その新たな問題を招くことなく引き抜きに対しても強いものとするにはさらなる改善の余地が残されているものであった。
実登３０４１８９９号公報特開平７−２７２７４号公報特開２００２−３５７２９４号公報実登２５８７４４９号公報 Therefore, as disclosed in Patent Document 4, a pull-out-resistant means having a structure in which a C-shaped split ring is interposed between the tube enlarged portion and the nut member in a state of being fitted in the circumferential groove of the tube enlarged portion. It is known to provide a pipe joint that is strong not only for the sealing function but also for pulling out the tube. However, in the pipe joint disclosed in Patent Document 4, since the number of parts is increased from 2 parts to 1 part (split ring) to 3 parts, the economic efficiency that was originally possessed is impaired. New problems arise. Therefore, there remains room for further improvement in making the pipe joint composed of the joint main body and the nut member strong against pulling out without causing new problems.
Noto 3041899 gazette Japanese Patent Laid-Open No. 7-27274 JP 2002-357294 A Noto 2587449 gazette

本発明の目的は、上記実情に鑑みて、継手本体とナット部材との２点で成る経済的なものとしながら、高い耐引き抜き性と良好なシール性との両立を図ることが可能となる管継手を提供する点にある。 In view of the above circumstances, the object of the present invention is a tube that can achieve both high pull-out resistance and good sealing properties while being economical, consisting of a joint body and a nut member. The point is to provide a joint.

請求項１に係る発明は、管継手において、少なくとも一つの端部に筒状のチューブ接続端部３２を設けた筒状の継手本体３０と、該継手本体３０のチューブ接続端部３２に接続すべき合成樹脂製のチューブ１０に外嵌され、前記チューブ接続端部３２に螺合されるナット部材５０を有し、前記継手本体３０と前記ナット部材５０それぞれが合成樹脂で形成され、前記チューブ接続端部３２が該チューブ接続端部３２の先端部に該チューブ接続端部３２の軸線に略垂直な受圧端壁３６を設けるとともに、該受圧端壁３６よりさらに軸方向に突出して前記チューブ１０の接続端部が拡径した状態で外嵌するインナ筒部３７を設け、前記ナット部材５０が該ナット部材５０のねじ孔の奥側に該ナット部材５０の軸線に略垂直な押圧端壁５２を設けるとともに、該押圧端壁５２に前記チューブ１０が押圧端壁５２側からねじ孔内に挿入するチューブ挿入孔５３を設け、軸方向で相対する一対の環状の凸部６０（１６０）と凹部７０（１７０）のうち、一方６０（１７０）を前記受圧端壁３６に設け、他方７０（１６０）を前記押圧端壁５２に設け、前記受圧端壁３６と前記押圧端壁７０の間で、前記チューブ１０の拡径部１３の端部がさらにフレア角度略９０度でフレアし、かつ、厚み方向に屈曲した状態で挟持することを特徴とするものである。 According to the first aspect of the present invention, in a pipe joint, a tubular joint body 30 provided with a tubular tube connection end 32 at at least one end is connected to the tube connection end 32 of the joint body 30. A nut member 50 which is externally fitted to the tube 10 made of a synthetic resin and screwed into the tube connection end 32, and the joint body 30 and the nut member 50 are each formed of a synthetic resin, and the tube connection The end portion 32 is provided with a pressure receiving end wall 36 substantially perpendicular to the axis of the tube connecting end portion 32 at the distal end portion of the tube connecting end portion 32, and further protrudes in the axial direction from the pressure receiving end wall 36. An inner cylinder portion 37 is provided to be externally fitted in a state where the diameter of the connecting end portion is expanded, and the nut member 50 is provided with a pressing end wall 52 substantially perpendicular to the axis of the nut member 50 on the back side of the screw hole of the nut member 50. Provide Both are provided with a tube insertion hole 53 through which the tube 10 is inserted into the screw hole from the pressing end wall 52 side in the pressing end wall 52, and a pair of annular convex portions 60 (160) and concave portions 70 ( 170), one side 60 (170) is provided on the pressure receiving end wall 36, and the other side 70 (160) is provided on the pressing end wall 52, and the tube is interposed between the pressure receiving end wall 36 and the pressing end wall 70. The end portions of the ten diameter-expanded portions 13 are further flared at a flare angle of about 90 degrees and are clamped in a state bent in the thickness direction.

請求項２に係る発明は、請求項１に記載の管継手において、前記インナ筒部３７が該インナ筒部３７の先端部外面にテーパー部３８を設け、前記チューブ挿入孔５３が前記チューブ１０の接続端部が拡径した状態で内嵌するために段差部５４を設け、該段差部５４の内径に前記チューブ１０の非拡径部１１より拡径部１３にかかる段差部１２を前記テーパー部３８に押し付けるエッジ部５５を設ける構成を付加したものである。 According to a second aspect of the present invention, in the pipe joint according to the first aspect, the inner cylindrical portion 37 is provided with a tapered portion 38 on the outer surface of the distal end portion of the inner cylindrical portion 37, and the tube insertion hole 53 is formed in the tube 10. A stepped portion 54 is provided in order to be fitted in a state where the diameter of the connecting end portion is expanded, and the stepped portion 12 applied to the expanded diameter portion 13 from the non-expanded diameter portion 11 of the tube 10 is formed on the inner diameter of the stepped portion 54. The structure which provides the edge part 55 pressed on 38 is added.

請求項３に係る発明は、請求項１又は２に記載の管継手において、前記継手本体３０と前記ナット部材５０それぞれがフッ素樹脂で形成されている構成を付加したものである。 According to a third aspect of the present invention, in the pipe joint according to the first or second aspect, a configuration in which each of the joint body 30 and the nut member 50 is formed of a fluororesin is added.

請求項１に係る発明によれば、継手本体３０のチューブ接続端部３２に設けたインナ筒部３７にチューブ１０の接続端部が拡径した状態で外嵌するとともに、ナット部材５０の螺進によってチューブ接続端部３２に設けた受圧端壁３６とナット部材５０に設けた押圧端壁５２の間で、チューブ１０の拡径部１３の端部をさらにフレア角度略９０度でフレアし、かつ、厚み方向に屈曲した状態で挟持するから、高いチューブ引き抜き強度を効果的に確保することができ、また、受圧端壁３６と押圧端壁５２の間でフレア角度略９０度のフレア部１４を屈曲する際に、凸部６０（１６０）と凹部７０（１７０）のうち、押圧端壁５２側の一方７０（１６０）がフレア角度略９０度のフレア部１４を受圧端壁３６側の他方６０（１７０）に強く押しけるから、そこでチューブ引き抜き強度をさらに高めながら、流体のシールに必要な面圧を効果的に発生し、流体の漏れを確実に防止することができる。その結果、継手本体３０とナット部材５０との２点で成る経済的なものとしながら、高い耐引き抜き性と良好なシール性との両立を図ることが可能となる管継手２０，２１を提供することができる。 According to the first aspect of the present invention, the nut 10 is screwed into the inner tube portion 37 provided at the tube connection end portion 32 of the joint body 30 with the connection end portion of the tube 10 being expanded in diameter. Between the pressure receiving end wall 36 provided at the tube connection end portion 32 and the pressing end wall 52 provided at the nut member 50, the end portion of the expanded diameter portion 13 of the tube 10 is further flared at a flare angle of approximately 90 degrees, and Since the tube is clamped in the thickness direction, a high tube pulling strength can be effectively secured, and the flare portion 14 having a flare angle of approximately 90 degrees between the pressure receiving end wall 36 and the pressing end wall 52 is provided. When bending, one of the convex portion 60 (160) and the concave portion 70 (170), the one 70 (160) on the pressing end wall 52 side replaces the flare portion 14 with the flare angle of approximately 90 degrees, and the other 60 on the pressure receiving end wall 36 side. Press strongly against (170) Since that, where while further increasing the tube pull-out strength, the surface pressure required for the sealing of the fluid effectively occur, it is possible to reliably prevent leakage of fluid. As a result, it is possible to provide pipe joints 20 and 21 that can achieve both a high pull-out resistance and a good sealing property while being economical, consisting of the joint body 30 and the nut member 50. be able to.

請求項２に係る発明によれば、ナット部材５０の螺進によってチューブ挿入孔５３の段差部５４の内径に設けたエッジ部５５が、チューブ１０の非拡径部１１より拡径部１３にかかる段差部１２を、インナ筒部３７の先端部外面に設けたテーパー部３８に強く押し付けるから、そこでチューブ引き抜き強度をさらに高めながら、シールに必要な面圧を効果的に発生し、流体の漏れを確実に防止することができる。 According to the second aspect of the present invention, the edge portion 55 provided on the inner diameter of the stepped portion 54 of the tube insertion hole 53 by the screwing of the nut member 50 is applied to the expanded diameter portion 13 from the non-expanded diameter portion 11 of the tube 10. Since the stepped portion 12 is strongly pressed against the tapered portion 38 provided on the outer surface of the distal end portion of the inner cylindrical portion 37, the surface pressure necessary for sealing is effectively generated while further increasing the tube pulling strength, thereby preventing fluid leakage. It can be surely prevented.

請求項３に係る発明によれば、継手本体３０とナット部材５０それぞれが耐薬品性及び耐熱性に優れた特性を有するフッ素樹脂で形成されているから、流体が薬液であるとか化学液体であっても、或いは高温流体であっても継手構造部分が変形して漏れやすくなることがなく、高い耐引き抜き性と良好なシール性が維持できるようになる。尚、フッ素樹脂は高温にも安定で、撥水性に優れ、摩擦係数が小さく、耐薬品性も極めて高く、電気絶縁性も高い点で好ましい。 According to the invention of claim 3, since each of the joint body 30 and the nut member 50 is formed of a fluororesin having excellent chemical resistance and heat resistance, the fluid is a chemical liquid or a chemical liquid. However, even if it is a high-temperature fluid, the joint structure portion is not deformed and is not easily leaked, and high pull-out resistance and good sealing performance can be maintained. Note that a fluororesin is preferable in that it is stable at high temperatures, excellent in water repellency, has a small coefficient of friction, has extremely high chemical resistance, and has high electrical insulation.

以下、本発明の実施の形態を図面に基づいて詳述する。図１は本発明の一実施の形態に係る管継手の断面図、図２は図１の要部拡大片側断面図である。 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view of a pipe joint according to an embodiment of the present invention, and FIG. 2 is an enlarged fragmentary side cross-sectional view of FIG.

図１〜図２において、本実施形態の管継手２０は、断面円形の流体移送路としての合成樹脂製のチューブ１０をポンプ，バルブ，フィルタ等の流体機器に連通接続するもので、合成樹脂製の継手本体３０と、同じく合成樹脂製のナット部材５０との２部品で構成されている。 1 to 2, a pipe joint 20 according to the present embodiment connects a synthetic resin tube 10 as a fluid transfer path having a circular cross section to fluid devices such as a pump, a valve, and a filter, and is made of a synthetic resin. The joint body 30 and a synthetic resin nut member 50 are comprised of two parts.

継手本体３０とナット部材５０の合成樹脂材料は、基本的にはチューブ１０と同じ合成樹脂材料が用いられる。例えばＰＴＥＦ（ポリテトラフルオロエチレン）、ＰＦＡ（テトラフルオロエチレン・パーフルオロアルキルビニルエーテル共重合体）、ＥＴＦＥ（テトラフルオロエチレン・エチレン共重合体）、ＰＶＤＦ（ポリビニリデンフルオライド）等のフッ素樹脂、その他、ＰＰ（ポリプロピレン）、ＰＥＥＫ（ポリエーテルエーテルケトン）が用いられる。 The synthetic resin material for the joint body 30 and the nut member 50 is basically the same synthetic resin material as that for the tube 10. For example, PTFE (polytetrafluoroethylene), PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), ETFE (tetrafluoroethylene / ethylene copolymer), PVDF (polyvinylidene fluoride), and other fluororesins, PP (polypropylene) and PEEK (polyetheretherketone) are used.

管継手２０を用いてチューブ１０を接続対象としての流体機器に接続するに当たり、チューブ１０の接続端部には、予め、チューブ１０の非拡径部１１に連なるテーパー段差部１２を経て、拡径した状態で継手本体５０の後述するインナ筒部３６に外嵌する直筒状の拡径部１３と、該拡径部１３の先端側をフレア角度略９０度にフレアしたものであるフレア部１４とを設けている。 In connecting the tube 10 to a fluid device as a connection target using the pipe joint 20, the connection end portion of the tube 10 is previously expanded through the tapered stepped portion 12 connected to the non-expanded diameter portion 11 of the tube 10. In this state, a straight cylindrical enlarged diameter portion 13 that is externally fitted to an inner cylindrical portion 36 described later of the joint main body 50, and a flare portion 14 that is formed by flaring the distal end side of the enlarged diameter portion 13 at a flare angle of approximately 90 degrees. Is provided.

拡径部１３とフレア部１４は、チューブ１０の接続端部を、例えばチューブ拡径器を用いて常温下或いは加熱しながら段階的に拡径加工した後、拡径部１３の先端側をさらに段階的にフレア加工することで設けることができる。 The enlarged diameter portion 13 and the flare portion 14 are obtained by further expanding the connecting end portion of the tube 10 in a stepwise manner at room temperature or while heating, for example, using a tube diameter enlarger, and then further expanding the distal end side of the enlarged diameter portion 13. It can be provided by flaring in stages.

継手本体３０は、図１の紙面左右方向に一直線状に延びる水平な軸線（中心線）ＣＬを有する直管部３１と、該直管部３１の左右端部より左右逆向きに該直管部３１と同軸上で突出する２つの筒状の接続端部、つまり筒状のチューブ接続端部としての筒状の第１雄ネジ部３２及び筒状の機器接続端部としての筒状の第２雄ねじ部３３とを一体に形成し、第１雄ねじ部３２側から直管部３１を経て第２雄ねじ部３３側に一直線状に貫通する流体移送路３４を形成している。 The joint body 30 includes a straight pipe portion 31 having a horizontal axis (center line) CL extending linearly in the left-right direction in FIG. 1, and the straight pipe portion in the opposite direction from the left and right ends of the straight pipe portion 31. Two cylindrical connection ends projecting coaxially with 31, that is, a cylindrical first male screw portion 32 as a cylindrical tube connection end and a cylindrical second as a cylindrical device connection end The male threaded portion 33 is formed integrally, and a fluid transfer path 34 is formed that penetrates in a straight line from the first male threaded portion 32 side through the straight pipe portion 31 to the second male threaded portion 33 side.

継手本体３０が形成する流体移送路３４は、チューブ１０が形成する流体移送路と略同じ直径を有する断面円形のものである。 The fluid transfer path 34 formed by the joint body 30 has a circular cross section having substantially the same diameter as the fluid transfer path formed by the tube 10.

直管部３１は、第１雄ネジ部３２及び第２雄ねじ部３３の基部となる該直管部３１の左右端部外面よりそれぞれ別々に径方向外側に張り出す把持部３５を設けている。該把持部３５は、直管部３１と同芯に形成されるとともに、その外面は６角等の多角形に形成されており、レンチ等の工具をかけることができる。 The straight pipe part 31 is provided with a grip part 35 that protrudes radially outward from the outer surfaces of the left and right end parts of the straight pipe part 31 that are the base parts of the first male screw part 32 and the second male screw part 33. The grip portion 35 is formed concentrically with the straight pipe portion 31, and the outer surface thereof is formed in a polygon such as a hexagon, and a tool such as a wrench can be applied.

本実施形態では直管部３１が短く、第１雄ネジ部３２及び第２雄ねじ部３３の基部となる直管部３１の左右端部が接近しているため、第１雄ネジ部３２の基部と第２雄ねじ部３３の基部とにそれぞれ別々に設けられる把持部３５は一つに繋がっている。 In this embodiment, since the straight pipe part 31 is short and the right and left end parts of the straight pipe part 31 that is the base part of the first male screw part 32 and the second male screw part 33 are close to each other, the base part of the first male screw part 32 And the grip part 35 provided separately on the base part of the second male screw part 33 are connected to one.

第１雄ネジ部３２は、該第１雄ネジ部３２の先端部に該第１雄ネジ部３２の軸線に垂直な平面内にある受圧端壁３６を設けるとともに、該受圧端壁３６よりさらに軸方向に第１雄ネジ部３２と同軸上で突出する、第１雄ねじ部３２の内径と同じ内径、第１雄ねじ部３２の外径より小径な外径を有し、チューブ１０の拡径部１３が外嵌する円筒状のインナ筒部３７を設けている。 The first male threaded portion 32 is provided with a pressure receiving end wall 36 in a plane perpendicular to the axis of the first male threaded portion 32 at the tip of the first male threaded portion 32, and further from the pressure receiving end wall 36. A diameter-enlarged portion of the tube 10 that has the same inner diameter as the inner diameter of the first male screw portion 32 and an outer diameter smaller than the outer diameter of the first male screw portion 32, which protrudes coaxially with the first male screw portion 32 in the axial direction. A cylindrical inner cylinder portion 37 to which 13 is fitted is provided.

インナ筒部３７には、該インナ筒部３７の先端部外面側の角部をチューブ１０のテーパー段差部１２に対応する角度で斜めに落とすようなテーパー部３８を設けている。 The inner cylindrical portion 37 is provided with a tapered portion 38 that drops the corner portion on the outer surface side of the distal end portion of the inner cylindrical portion 37 at an angle corresponding to the tapered stepped portion 12 of the tube 10.

インナ筒部３７にチューブ１０の拡径部１３が外嵌した状態では、チューブ１０のフレア部１４におけるフレア前は該チューブ１０の内面であった一表面に受圧端壁３６が軸方向で対向する。 In a state in which the expanded diameter portion 13 of the tube 10 is externally fitted to the inner cylindrical portion 37, the pressure receiving end wall 36 faces the one surface that was the inner surface of the tube 10 before the flare in the flare portion 14 of the tube 10 in the axial direction. .

第２雄ねじ部３３は、チューブ１０の接続対象としての流体機器のチューブ接続口に設けられた相手方の雌ねじ部に螺合可能なものである。第２雄ねじ部３３と相手方の雌ねじ部のねじは、シール性を発揮するテーパーねじである。 The second male screw portion 33 can be screwed into a mating female screw portion provided in a tube connection port of a fluid device as a connection target of the tube 10. The screw of the second male screw portion 33 and the counterpart female screw portion is a taper screw that exhibits sealing performance.

チューブ１０が形成する流体移送路と継手本体３０が形成する流体移送路３４との継ぎ目で液溜まりが発生するのを防止するため、継手本体３０が形成する流体移送路３４における第１雄ネジ部３２側の開口縁、つまりインナ筒部３７の先端面と内周面との角部には面取り部３９を設けている。 In order to prevent liquid pooling from occurring at the joint between the fluid transfer path formed by the tube 10 and the fluid transfer path 34 formed by the joint body 30, the first male screw portion in the fluid transfer path 34 formed by the joint body 30 A chamfered portion 39 is provided at the opening edge on the 32 side, that is, at the corner between the tip surface and the inner peripheral surface of the inner cylinder portion 37.

ナット部材５０は、ねじ孔の一方が閉鎖された袋ナットにおけるねじ孔の奥側からチューブ１０を挿入できるようにしたユニオンナットで成り、第１雄ネジ部３２に螺合可能なナット部５１と、該ナット部５１のねじ孔の一方を閉鎖するよう該ナット部５１の一端部（図１の左端部）から径方向内側に直角に延出され、ナット部５１を第１雄ネジ部３２に螺合したとき、ナット部材５０のねじ軸、つまり軸線ＣＬに垂直な平面内にあり、第１雄ネジ部３２の受圧端壁３６と軸方向で対向する押圧端壁５２と、該押圧端壁５２の中心部を開口する内外面貫通の円形なチューブ挿入孔５３とを同軸上に一体に形成している。 The nut member 50 is a union nut that allows the tube 10 to be inserted from the back side of the screw hole in the cap nut in which one of the screw holes is closed, and a nut portion 51 that can be screwed into the first male screw portion 32. The nut portion 51 is extended perpendicularly radially inward from one end portion (left end portion in FIG. 1) of the nut portion 51 so as to close one of the screw holes of the nut portion 51, and the nut portion 51 is changed to the first male screw portion 32. A pressure end wall 52 that is in a plane perpendicular to the screw shaft of the nut member 50, that is, the axis CL, and is opposed to the pressure receiving end wall 36 of the first male screw portion 32 in the axial direction when screwed, and the pressure end wall A circular tube insertion hole 53 penetrating the inner and outer surfaces that opens the center of 52 is integrally formed on the same axis.

ナット部材５０が形成するチューブ挿入孔５３は、そこを挿通するチューブ１０との間に僅かなクリアランスを設ける孔径を有しており、該クリアランスによりチューブ１０がナット部材５０と連れ回りするのを防止している。 The tube insertion hole 53 formed by the nut member 50 has a hole diameter that provides a slight clearance between the tube 10 and the tube 10 inserted therethrough, and the clearance prevents the tube 10 from rotating together with the nut member 50. is doing.

チューブ挿入孔５３には、チューブ１０の拡径部１３を内嵌するために段差部５４を設けており、段差部５４よりチューブ挿入方向手前側（左側）のチューブ挿入孔５３には、チューブ１０の非拡径部１１の先端部が内嵌され、段差部５４よりチューブ挿入方向奥側のチューブ挿入孔５３には、チューブ１０のテーパー段差部１２及び拡径部１３が内嵌される。 The tube insertion hole 53 is provided with a stepped portion 54 for fitting the enlarged diameter portion 13 of the tube 10 therein. The tube insertion hole 53 on the front side (left side) of the tube insertion direction from the stepped portion 54 is provided in the tube 10. The tapered step portion 12 and the enlarged diameter portion 13 of the tube 10 are fitted in the tube insertion hole 53 on the far side of the tube insertion direction from the step portion 54.

段差部５４の内径には、チューブ１０のテーパー段差部１２をインナ筒部３７の先端部外面に設けたテーパー部３８に押し付けるエッジ部５５を設けている。 On the inner diameter of the stepped portion 54, an edge portion 55 that presses the tapered stepped portion 12 of the tube 10 against the tapered portion 38 provided on the outer surface of the distal end portion of the inner cylinder portion 37 is provided.

インナ筒部３７にチューブ１０の拡径部１３が外嵌した状態の第１雄ネジ部３２にナット部５１を螺合した状態では、チューブ１０のフレア部１４におけるフレア前は該チューブ１０の外面であった他表面に押圧端壁５２が軸方向で対向する。つまりチューブ１０のフレア部１４が受圧端壁３６と押圧端壁５２との間に配置され、受圧端壁３６と押圧端壁５２とがチューブ１０のフレア部１４を厚さ方向で挟んで対向する。 In a state where the nut portion 51 is screwed into the first male screw portion 32 in a state where the expanded diameter portion 13 of the tube 10 is externally fitted to the inner cylinder portion 37, the flare portion 14 of the tube 10 before flare is the outer surface of the tube 10. The pressing end wall 52 faces the other surface in the axial direction. That is, the flare portion 14 of the tube 10 is disposed between the pressure receiving end wall 36 and the pressing end wall 52, and the pressure receiving end wall 36 and the pressing end wall 52 face each other with the flare portion 14 of the tube 10 sandwiched in the thickness direction. .

そして、軸方向で相対する一対の円環状の凸部６０と凹部７０のうち、一方を第１雄ねじ部３２の受圧端壁３６に設け、他方をナット部材５０の押圧端壁５２に設け、受圧端壁３６と押圧端壁５２の間で、チューブ１０のフレア部１４を厚み方向に屈曲した状態で挟持するもので、本実施形態では、チューブ１０のフレア部１４を同芯な波形を付けた状態で挟持するよう凸部６０を受圧端壁３６側に設け、凹部７０を押圧端壁５２側に設けている。 One of the pair of annular convex portions 60 and concave portions 70 facing each other in the axial direction is provided on the pressure receiving end wall 36 of the first male screw portion 32, and the other is provided on the pressing end wall 52 of the nut member 50. The flare portion 14 of the tube 10 is sandwiched between the end wall 36 and the pressing end wall 52 in a state bent in the thickness direction. In this embodiment, the flare portion 14 of the tube 10 has a concentric waveform. The convex portion 60 is provided on the pressure receiving end wall 36 side and the concave portion 70 is provided on the pressing end wall 52 side so as to be held in a state.

凸部６０は、受圧端面３６において、チューブ１０のフレア部１４における一表面の径方向略中央部に突き合わせる径方向略中央部をその径方向内側と外側の受圧端面３６よりさらに軸方向（ナット部材５０の螺退方向：左方向）に第１雄ねじ部と同軸上で突出させる円筒状の突条部で成り、受圧端面３６に同芯な波形を付けている。つまり受圧端面３６において、凸部６０より径方向内側部が波形の最内周の谷部３６ａ、凸部６０である径方向中央部が最内周の谷部３６ａに連なる山部３６ｂ、凸部６０より径方向外側部が山部３６ｂに連なる最外周の谷部３６ｃになる。 In the pressure receiving end surface 36, the convex portion 60 has a substantially radial central portion that abuts the substantially central portion in the radial direction of one surface of the flare portion 14 of the tube 10 in the axial direction (nut) more than the radially inner and outer pressure receiving end surfaces 36. The member 50 is formed of a cylindrical ridge protruding coaxially with the first male screw portion in the screwing direction (left direction), and the pressure receiving end surface 36 has a concentric waveform. In other words, in the pressure receiving end surface 36, the radially inner portion of the convex portion 60 is corrugated on the innermost circumferential valley portion 36a, and the radial central portion, which is the convex portion 60, is connected to the innermost circumferential valley portion 36a. The outer circumferential portion from 60 is the outermost trough portion 36c that continues to the peak portion 36b.

凸部６０の片側断面形状は、角部を角張らせた矩形状に形成され、先端面は軸線ＣＬと垂直な平面内にあり、内外周面は軸線ＣＬを軸とする大小径の異なる円筒面内にあり、受圧端面３６の片側断面形状は方形波のような形状になる。 The one-side cross-sectional shape of the convex portion 60 is formed in a rectangular shape with angular corners, the tip end surface is in a plane perpendicular to the axis CL, and the inner and outer peripheral surfaces are cylinders having different large and small diameters about the axis CL. It is in the plane, and the cross-sectional shape of one side of the pressure receiving end face 36 is a square wave.

受圧端面３６は、凸部６０の先端部内外周の角部によって形成されたエッジ部６１，６２を設けている。 The pressure receiving end surface 36 is provided with edge portions 61 and 62 formed by corner portions on the inner and outer circumferences of the tip portion of the convex portion 60.

凹部７０は、押圧端壁５２において、凸部３６ｃの先端面と対向する径方向略中央部であって、チューブ１０のフレア部１４における他表面の径方向略中央部に突き合わせる径方向略中央部を、凸部３６ｃの内径と外径それぞれにフレア部１４の厚みより小さい所定値を加えた内径と外径で、つまり凸部３６ｃの厚みより径方内側と外側に所定値だけ拡大した径方向幅（溝幅）で、軸方向（ナット部材５０の螺退方向：左方向）に後退させる、受圧端面３６と同芯な円環状の溝部で成り、押圧端面５２に受圧端面３６の波形に対応した（谷部と山部が逆）同芯な波形を付けている。つまり押圧端面５２において、凹部７０より径方向内側部が波形の最内周の山部５２ａ、凹部７０である径方向中央部が最内周の山部５２ａに連なる谷部５２ｂ、凹部７０より径方向外側部が谷部５２ｂに連なる最外周の山部５２ｃになる。 The concave portion 70 is a substantially central portion in the radial direction facing the tip end surface of the convex portion 36 c in the pressing end wall 52, and is substantially central in the radial direction that abuts against the substantially central portion in the radial direction of the other surface of the flare portion 14 of the tube 10. The inner diameter and the outer diameter of the convex portion 36c are added with a predetermined value smaller than the thickness of the flare portion 14, respectively, that is, the diameter expanded by a predetermined value radially inward and outward from the thickness of the convex portion 36c. It consists of an annular groove that is concentric with the pressure receiving end surface 36 and that has a direction width (groove width) and is retracted in the axial direction (screwing direction of the nut member 50: leftward). Corresponding corrugations (reverse valley and mountain) are attached. That is, in the pressing end surface 52, the radially inner part is a corrugated innermost peak 52 a from the concave part 70, and the radial central part, which is the concave part 70, is a diameter from the valley 52 b and the concave part 70 connected to the innermost peak 52 a. The outer side portion in the direction becomes the outermost peak portion 52c continuous with the valley portion 52b.

凹部７０の片側断面形状は、ナット部材５０の螺退方向に開口したコ字形に形成され、底面は軸線ＣＬと垂直な平面内にあり、内外周面は軸線ＣＬを軸とする大小径の異なる円筒面内にあり、押圧端壁５２の片側断面形状は方形波のような形状になる。 The one-side cross-sectional shape of the recess 70 is formed in a U-shape opening in the screwing direction of the nut member 50, the bottom surface is in a plane perpendicular to the axis line CL, and the inner and outer peripheral surfaces are different in large and small diameters about the axis line CL. It exists in a cylindrical surface, and the one-side cross-sectional shape of the press end wall 52 becomes a shape like a square wave.

押圧端壁５２は、凹部７０の開口部内外周の角部によって形成されたエッジ部７１，７２を設けている。また押圧端壁５２の内径にもエッジ部７３を設けている。 The pressing end wall 52 is provided with edge portions 71 and 72 formed by corners on the inner and outer periphery of the opening of the recess 70. An edge portion 73 is also provided on the inner diameter of the pressing end wall 52.

インナ筒部３７にチューブ１０の拡径部１３が外嵌した状態の第１雄ネジ部３２にナット部５１を螺合した状態では、チューブ１０のフレア部１４が波形の受圧端壁３６と押圧端壁５２との間に配置され、波形の受圧端壁３６と押圧端壁５２とがチューブ１０のフレア部１４を厚さ方向で挟んで対向する。具体的には、受圧端面３６の最内周の谷部３６ａと押圧端面５２の最内周の山部５２ａ、受圧端面３６の山部３６ｂと押圧端面５２の谷部５２ｂ、受圧端面３６の最外周の谷部３６ｃと押圧端面５２の最外周の山部５２ｃそれぞれがチューブ１０のフレア部１４を厚さ方向で挟んで対向する。 In a state where the nut portion 51 is screwed into the first male screw portion 32 in a state where the expanded diameter portion 13 of the tube 10 is fitted on the inner cylinder portion 37, the flare portion 14 of the tube 10 presses against the corrugated pressure receiving end wall 36. It arrange | positions between the end walls 52, and the corrugated pressure-receiving end wall 36 and the press end wall 52 oppose on both sides of the flare part 14 of the tube 10 in thickness direction. Specifically, the innermost valley portion 36 a of the pressure receiving end surface 36 and the innermost circumferential peak portion 52 a of the pressing end surface 52, the peak portion 36 b of the pressure receiving end surface 36, the valley portion 52 b of the pressing end surface 52, and the innermost portion of the pressure receiving end surface 36. Each of the outer peripheral valley portion 36c and the outermost peripheral peak portion 52c of the pressing end surface 52 are opposed to each other with the flare portion 14 of the tube 10 sandwiched in the thickness direction.

以上の構成において、チューブ１０の接続端部を継手本体３０に接続するには、チューブ１０の接続端部を拡径及びフレア加工する前に、該チューブ１０の接続端部をナット部材５０のチューブ挿入孔５３に押圧端壁５２の外側より挿入し、ナット部材５０をチューブ１０に外嵌してからチューブ１０の接続端部を拡径及びフレア加工して非拡径部１１からテーパー段差部１２を経て拡径した直筒状の拡径部１３及び該拡径部１３の先端側をフレア角度略９０度にフレアしたフレア部１４を設ける。そして、チューブ１０の拡径部１５を継手本体３０の第１雄ねじ部３２に設けたインナ筒部３７に外嵌し、チューブ１０のフレア部１４の一表面を第１雄ねじ部３２に設けた受圧端壁３６と軸方向で対向させた状態で、予めチューブ１０に外嵌してあるナット部材５０のナット部５１を継手本体３０の第１雄ねじ部３２に螺合することにより完了する。 In the above configuration, in order to connect the connection end of the tube 10 to the joint body 30, the connection end of the tube 10 is connected to the tube of the nut member 50 before the connection end of the tube 10 is expanded and flared. The insertion end 53 is inserted from the outer side of the pressing end wall 52, and the nut member 50 is externally fitted to the tube 10, and then the connection end of the tube 10 is expanded and flared to taper the stepped portion 12 from the non-expanded portion 11. And a flared portion 14 having a flare angle of about 90 degrees on the tip side of the enlarged diameter portion 13 is provided. Then, the expanded diameter portion 15 of the tube 10 is externally fitted to the inner cylinder portion 37 provided in the first male screw portion 32 of the joint body 30, and the pressure receiving pressure in which the one surface of the flare portion 14 of the tube 10 is provided in the first male screw portion 32. This is completed by screwing the nut portion 51 of the nut member 50 that is preliminarily fitted to the tube 10 into the first male screw portion 32 of the joint body 30 in a state of facing the end wall 36 in the axial direction.

即ち、ナット部材５０のナット部５１を継手本体３０の第１雄ねじ部３２に螺合することにより、ナット部材５０の押圧端壁５２とチューブ１０のフレア部１４の他表面とが軸方向で対向し、チューブ１０のフレア部１４が受圧端壁３６と押圧端壁５２との間に配置され、受圧端壁３６と押圧端壁５２とがチューブ１０のフレア部１４を厚さ方向で挟んで対向する。この状態で、ナット部材５０を回しながらナット部５１を継手本体３０の第１雄ねじ部３２の外面で軸線ＣＬに沿って基部側に漸次螺進させると、押圧端壁５２が受圧端壁３６に漸次接近する。ここで、受圧端壁３６には該受圧端壁に設けた凸部６０によって同芯な波形が付けられ、押圧端壁５２には該押圧端壁５２に設けた凹部７０によって受圧端壁３６の波形に対応する同芯な波形を付けてある。それゆえ、押圧端壁５２が受圧端壁３６に漸次接近すると、押圧端壁５２が最内周の山部５２ａと最外周の山部５２ｃとでフレア部１４の他表面に突き合い接触し、フレア部１４を押し、遂にはフレア部１４の一表面を受圧端壁３６に山部３６ｂで突き合い接触させる。 That is, by screwing the nut portion 51 of the nut member 50 into the first male screw portion 32 of the joint body 30, the pressing end wall 52 of the nut member 50 and the other surface of the flare portion 14 of the tube 10 face each other in the axial direction. The flare portion 14 of the tube 10 is disposed between the pressure receiving end wall 36 and the pressing end wall 52, and the pressure receiving end wall 36 and the pressing end wall 52 face each other with the flare portion 14 of the tube 10 sandwiched in the thickness direction. To do. In this state, when the nut portion 51 is gradually screwed to the base side along the axis CL on the outer surface of the first male screw portion 32 of the joint body 30 while turning the nut member 50, the pressing end wall 52 is moved to the pressure receiving end wall 36. Gradually approach. Here, the pressure receiving end wall 36 is provided with a concentric waveform by a convex portion 60 provided on the pressure receiving end wall, and the pressing end wall 52 is provided with a concave portion 70 provided on the pressing end wall 52. A concentric waveform corresponding to the waveform is attached. Therefore, when the pressing end wall 52 gradually approaches the pressure receiving end wall 36, the pressing end wall 52 abuts against and contacts the other surface of the flare portion 14 at the innermost crest 52a and the outermost crest 52c, The flare part 14 is pushed, and finally one surface of the flare part 14 is brought into contact with the pressure receiving end wall 36 at the peak part 36b.

この状態で、ナット部材５０をさらに回してナット部５１を継手本体３０の第１雄ねじ部３２の外面で軸線ＣＬに沿って基部側に螺進させると、フレア部１４における受圧端壁３６の山部３６ｂに突き合い接触していない内周部と外周部が押圧端壁５２の最内周の山部５２ａと最外周の山部５２ｃとでさらに押されて、受圧端壁３６の最内周の谷部３６ａと最外周の谷部３６ｃとに押し込まれ、波形の受圧端壁３６と押圧端壁５２との間で、フレア部１４が厚み方向に屈曲した状態、つまり同芯な波形が付けられた状態で強く挟持されるから、高いチューブ引き抜き強度を効果的に確保することができ、高いチューブ引き抜き強度でチューブ１０の接続端部が継手本体３０に接続される。 In this state, when the nut member 50 is further rotated and the nut portion 51 is screwed to the base side along the axis CL on the outer surface of the first male screw portion 32 of the joint body 30, the peak of the pressure receiving end wall 36 in the flare portion 14. The inner peripheral portion and the outer peripheral portion that are not in contact with and contact with the portion 36 b are further pressed by the innermost peripheral peak portion 52 a and the outermost peripheral peak portion 52 c of the pressing end wall 52, and the innermost peripheral portion of the pressure receiving end wall 36. Between the corrugated pressure receiving end wall 36 and the pressing end wall 52, that is, the flare portion 14 is bent in the thickness direction, that is, a concentric corrugation is applied. In this state, the tube 10 is strongly clamped, so that a high tube pull-out strength can be effectively ensured, and the connection end portion of the tube 10 is connected to the joint body 30 with a high tube pull-out strength.

また、波形の受圧端壁３６と押圧端壁５２との間では、押圧端壁７０に設けたエッジ部７１，７２によってフレア部１４の一表面を受圧端壁３６に設けたエッジ部６１，６２に強く押し付けるから、そこでチューブ引き抜き強度をさらに高めながら、流体のシールに必要な面圧を効果的に発生し、流体の漏れを確実に防止した状態でチューブ１０の接続端部が継手本体３０に接続される。 Further, between the corrugated pressure receiving end wall 36 and the pressing end wall 52, edge portions 61, 62 provided on the pressure receiving end wall 36 with one surface of the flare portion 14 by the edge portions 71, 72 provided on the pressing end wall 70. Therefore, the connection end of the tube 10 is connected to the joint body 30 in a state where the surface pressure necessary for sealing the fluid is effectively generated and the leakage of the fluid is surely prevented while further increasing the tube pulling strength. Connected.

また、ナット部材５０の螺進によってチューブ挿入孔５３の段差部５４の内径に設けたエッジ部５５が、チューブ１０のテーパー段差部１２を、インナ筒部３７の先端部外面に設けたテーパー部３８に強く押し付けるから、そこでチューブ引き抜き強度をさらに高めながら、シールに必要な面圧を効果的に発生し、流体の漏れを確実に防止することができる。 Further, the edge portion 55 provided on the inner diameter of the stepped portion 54 of the tube insertion hole 53 by the screwing of the nut member 50 is the tapered portion 38 provided with the tapered stepped portion 12 of the tube 10 on the outer surface of the distal end portion of the inner cylindrical portion 37. Therefore, while further increasing the tube pulling strength, the surface pressure required for sealing can be effectively generated, and fluid leakage can be reliably prevented.

以上、本実施の形態は、本発明に係る管継手の好適な一実施の形態をチューブ１０を流体機器のチューブ接続口にストレートに接続する管継手２０で説明したが、本発明はそれに限定されることなく、その要旨を逸脱しない範囲内で種々変形実施することができる。例えばチューブ１０同士を接続するエルボ，チーズ，クロス等の管継手に実施することができ、この場合は、図１の把持部３５より左側のチューブ接続構造がエルボ，チーズ，クロス等の継手本体の管部の端部に設けられる。また、本実施の形態では、一対の凸部６０と凹部７０を一組しか設けていないが、複数組を径方向に所定間隔で多重に設けてもよい。また、凸部６０と凹部７０の形状を大きくしたり小さくすることにより、受圧端壁３６と押圧端壁５２の波形の高さや幅を変更することができる。 As mentioned above, although this Embodiment demonstrated one suitable embodiment of the pipe joint which concerns on this invention with the pipe joint 20 which connects the tube 10 straight to the tube connection port of a fluid apparatus, this invention is limited to it. Without departing from the spirit of the present invention, various modifications can be made. For example, it can be applied to pipe joints such as elbows, cheeses, and crosses that connect the tubes 10 to each other. In this case, the tube connection structure on the left side of the grip portion 35 in FIG. Provided at the end of the tube. Moreover, in this Embodiment, although only one pair of a pair of convex part 60 and the recessed part 70 is provided, you may provide multiple sets in multiple at predetermined intervals in radial direction. In addition, by increasing or decreasing the shapes of the convex portion 60 and the concave portion 70, the height and width of the corrugations of the pressure receiving end wall 36 and the pressing end wall 52 can be changed.

また、管継手２０を用いてチューブ１０を接続対象に接続するに当たり、チューブ１０の接続端部に、予め、テーパー段差部１２及び拡径部１３とフレア角度略９０度のフレア部１４を設けたが、チューブ１０の管壁の厚みによっては、例えばラッパ状のフレア部のみを設けるだけでも、図１及び図２に示す状態でチューブ１０の接続端部を継手本体３０の第１雄ねじ部３２に接続することができる。従って、チューブ１０の接続端部における初期形状は、チューブ１０の材質や管壁の厚み及び施工性を考慮して適宜設定されるものであり、接続後のチューブ１０の接続端部形状（テーパー段差部１２及び拡径部１３とフレア角度略９０度のフレア部１４）と同じ形状を与える必要はない。 Further, in connecting the tube 10 to the connection object using the pipe joint 20, the tapered stepped portion 12 and the enlarged diameter portion 13 and the flare portion 14 having a flare angle of approximately 90 degrees are provided in advance at the connection end portion of the tube 10. However, depending on the thickness of the tube wall of the tube 10, for example, even if only the trumpet-shaped flare portion is provided, the connection end portion of the tube 10 is connected to the first male screw portion 32 of the joint body 30 in the state shown in FIGS. 1 and 2. Can be connected. Accordingly, the initial shape at the connection end of the tube 10 is appropriately set in consideration of the material of the tube 10, the thickness of the tube wall, and workability, and the connection end shape of the tube 10 after connection (taper step) It is not necessary to give the same shape as the portion 12 and the enlarged diameter portion 13 and the flare portion 14) having a flare angle of approximately 90 degrees.

次に、図３を参照して本発明の他の実施の形態に係る管継手を説明する。図３は本発明の他の実施の形態に係る管継手の要部片側断面図である。 Next, a pipe joint according to another embodiment of the present invention will be described with reference to FIG. FIG. 3 is a fragmentary sectional side view of a main part of a pipe joint according to another embodiment of the present invention.

本実施形態の管継手２１は、軸方向で相対する一対の環状の凸部と凹部のうち、凸部を押圧端壁５２に設け、凹部を受圧端壁３６に設けた点が、図１，図２に示した管継手２０と異なるだけであり、その他の構造は同じである。 The pipe joint 21 of the present embodiment has a feature that, of the pair of annular convex portions and concave portions opposed in the axial direction, the convex portion is provided on the pressing end wall 52 and the concave portion is provided on the pressure receiving end wall 36 as shown in FIG. It is only different from the pipe joint 20 shown in FIG. 2, and the other structure is the same.

押圧端壁５２に設ける凸部１６０と受圧端壁３６に設ける凹部１７０は、受圧端壁３６に設ける凸部６０と押圧端壁５２に設ける凹部７０より大形に形成され、特に、凸部１６０においては軸方向の長さ、凹部１７０においては軸方向の高さが大きくなっている。 The convex portion 160 provided on the pressing end wall 52 and the concave portion 170 provided on the pressure receiving end wall 36 are formed larger than the convex portion 60 provided on the pressure receiving end wall 36 and the concave portion 70 provided on the pressing end wall 52, and in particular, the convex portion 160. The length in the axial direction is large, and the height in the axial direction is large in the recess 170.

また、凹部１７０の内径と凸部１６０の内径の差及び凹部１７０の外径と凸部１６０の外径の差は、インナ筒部３７にチューブ１０の拡径部１３が外嵌した状態の第１雄ネジ部３２にナット部５１を螺合したとき、径方向で対向する凹部１７０の内周面１７０ａと凸部１６０の内周面１６０ａの間及び凹部１７０の外周面１７０ｂと凸部１６０の外周面１６０ｂの間に、それぞれチューブ１０のフレア部１４の厚み（チューブ１０の管壁の厚み）より小さい同じ隙間を与える所定寸法に設定されている。すなわち、図４に示すように、凹部１７０の径方向の幅をＴ、凸部１６０の径方向の厚みをｔ１、チューブ１０のフレア部１４の厚みをｔ２とした場合、Ｔ＜ｔ１＋ｔ２×２とし、凸部１６０とフレア部１４における凸部１６０の内周面１６０ａより先端面を経て外周面１６０ｂに折り返した状態で屈曲した部分とを凹部１７０に圧入するように構成されている。 Further, the difference between the inner diameter of the concave portion 170 and the inner diameter of the convex portion 160 and the difference between the outer diameter of the concave portion 170 and the outer diameter of the convex portion 160 are the values in the state where the expanded diameter portion 13 of the tube 10 is externally fitted to the inner cylindrical portion 37. When the nut portion 51 is screwed into the male threaded portion 32, the space between the inner peripheral surface 170a of the concave portion 170 and the inner peripheral surface 160a of the convex portion 160 and the outer peripheral surface 170b of the concave portion 170 and the convex portion 160 that are opposed in the radial direction. Between the outer peripheral surfaces 160b, predetermined dimensions are set to give the same gaps smaller than the thickness of the flare portion 14 of the tube 10 (the thickness of the tube wall of the tube 10). That is, as shown in FIG. 4, when the radial width of the concave portion 170 is T, the radial thickness of the convex portion 160 is t1, and the thickness of the flare portion 14 of the tube 10 is t2, T <t1 + t2 × 2. The convex portion 160 and the bent portion of the flare portion 14 in a state of being folded back to the outer peripheral surface 160b from the inner peripheral surface 160a of the convex portion 160 through the tip surface are configured to be press-fitted into the concave portion 170.

以上の構成において、チューブ１０の接続端部を継手本体３０に接続するには、チューブ１０の接続端部を拡径及びフレア加工する前に、該チューブ１０の接続端部をナット部材５０のチューブ挿入孔５３に押圧端壁５２の外側より挿入し、ナット部材５０をチューブ１０に外嵌してからチューブ１０の接続端部を拡径及びフレア加工して非拡径部１１からテーパー段差部１２を経て拡径した直筒状の拡径部１３及び該拡径部１３の先端側をフレア角度略９０度にフレアしたフレア部１４を設ける。そして、チューブ１０の拡径部１５を継手本体３０の第１雄ねじ部３２に設けたインナ筒部３７に外嵌し、チューブ１０のフレア部１４の一表面と凹部１７０を設けた受圧端壁３６とを突き合い接触させた状態で、予めチューブ１０に外嵌してあるナット部材５０のナット部５１を継手本体３０の第１雄ねじ部３２に螺合することにより完了する。 In the above configuration, in order to connect the connection end of the tube 10 to the joint body 30, the connection end of the tube 10 is connected to the tube of the nut member 50 before the connection end of the tube 10 is expanded and flared. The insertion end 53 is inserted from the outer side of the pressing end wall 52, and the nut member 50 is externally fitted to the tube 10, and then the connection end of the tube 10 is expanded and flared to taper the stepped portion 12 from the non-expanded portion 11. And a flared portion 14 having a flare angle of about 90 degrees on the tip side of the enlarged diameter portion 13 is provided. Then, the diameter-enlarged portion 15 of the tube 10 is externally fitted to the inner cylinder portion 37 provided in the first male screw portion 32 of the joint body 30, and the pressure receiving end wall 36 provided with one surface of the flare portion 14 and the concave portion 170 of the tube 10. Is completed by screwing the nut portion 51 of the nut member 50 that is preliminarily fitted to the tube 10 into the first male screw portion 32 of the joint body 30.

即ち、ナット部材５０のナット部５１を継手本体３０の第１雄ねじ部３２に螺合することにより、凸部１６０を設けた押圧端壁５２とチューブ１０のフレア部１４の他表面とが軸方向で対向し、チューブ１０のフレア部１４が受圧端壁３６と押圧端壁５２との間に配置され、受圧端壁３６と押圧端壁５２とがチューブ１０のフレア部１４を厚さ方向で挟んで対向する。この状態で、ナット部材５０を回しながらナット部５１を継手本体３０の第１雄ねじ部３２の外面で軸線ＣＬに沿って基部側に漸次螺進させると、押圧端壁５２が受圧端壁３６に漸次接近し、凸部１６０の先端面が、フレア部１４において、受圧端壁３６の凹部１７０によって該受圧端壁３６とは突き合い接触しておらず支えられていないに部分の他表面に突き合い接触する。 That is, when the nut portion 51 of the nut member 50 is screwed into the first male screw portion 32 of the joint body 30, the pressing end wall 52 provided with the convex portion 160 and the other surface of the flare portion 14 of the tube 10 are axial. The flare portion 14 of the tube 10 is disposed between the pressure receiving end wall 36 and the pressing end wall 52, and the pressure receiving end wall 36 and the pressing end wall 52 sandwich the flare portion 14 of the tube 10 in the thickness direction. Opposite. In this state, when the nut portion 51 is gradually screwed to the base side along the axis CL on the outer surface of the first male screw portion 32 of the joint body 30 while turning the nut member 50, the pressing end wall 52 is moved to the pressure receiving end wall 36. Gradually approaching, the tip surface of the convex portion 160 is not in contact with and supported by the concave portion 170 of the pressure receiving end wall 36 in the flare portion 14 but hits the other surface of the portion. Make contact.

この状態で、ナット部材５０をさらに回してナット部５１を継手本体３０の第１雄ねじ部３２の外面で軸線ＣＬに沿って基部側に螺進させると、フレア部１４の径方向中央部が凸部１６０の先端面で押されて凹部１７０に押し込まれ、受圧端壁３６と押圧端壁５２との間で、フレア部１４が凸部１６０と凹部１７０に沿って厚み方向に屈曲した状態で強く挟持されるから、高いチューブ引き抜き強度を効果的に確保することができ、高いチューブ引き抜き強度でチューブ１０の接続端部が継手本体３０に接続される。また、そこで流体のシールに必要な面圧を効果的に発生し、流体の漏れを確実に防止した状態でチューブ１０の接続端部が継手本体３０に接続される。 In this state, when the nut member 50 is further turned and the nut portion 51 is screwed to the base side along the axis CL on the outer surface of the first male screw portion 32 of the joint body 30, the radial center portion of the flare portion 14 is convex. It is pushed by the tip surface of the portion 160 and pushed into the concave portion 170, and is strong in a state where the flare portion 14 is bent in the thickness direction along the convex portion 160 and the concave portion 170 between the pressure receiving end wall 36 and the pressing end wall 52. Since it is clamped, a high tube pull-out strength can be effectively ensured, and the connection end portion of the tube 10 is connected to the joint body 30 with a high tube pull-out strength. Further, the contact end portion of the tube 10 is connected to the joint body 30 in a state where the surface pressure necessary for sealing the fluid is effectively generated and the fluid leakage is reliably prevented.

具体的には、フレア部１４の内周部と外周部の一表面を、押圧端壁５２で受圧端壁３６に押し付け、チューブ１０の挿抜方向（軸方向）で強く挟持するから、高いチューブ引き抜き強度を効果的に確保することができ、高いチューブ引き抜き強度でチューブ１０の接続端部が継手本体３０に接続される。また、そこで流体のシールに必要な面圧を効果的に発生し、流体の漏れを確実に防止することができる。 Specifically, one surface of the inner peripheral portion and the outer peripheral portion of the flare portion 14 is pressed against the pressure receiving end wall 36 by the pressing end wall 52 and is strongly held in the insertion / extraction direction (axial direction) of the tube 10. The strength can be effectively secured, and the connecting end portion of the tube 10 is connected to the joint body 30 with a high tube pull-out strength. In addition, it is possible to effectively generate a surface pressure necessary for sealing the fluid and reliably prevent fluid leakage.

また、フレア部１４の内周部と外周部の間の屈曲部の一表面を、凸部１６０の内周面１６０ａと外周面１６０ｂで凹部１７０の内周面１７０ａと外周面１７０ｂに押し付け、径方向で強く挟持し、そこで流体のシールに必要な面圧を径方向に効果的に発生するから、高温用途による合成樹脂（継手本体）のクリープが発生したり、振動等によるナット部材５０の緩みが発生しても、高い耐引き抜き性と良好なシール性を保持することができる。 In addition, one surface of the bent portion between the inner peripheral portion and the outer peripheral portion of the flare portion 14 is pressed against the inner peripheral surface 170a and the outer peripheral surface 170b of the concave portion 170 by the inner peripheral surface 160a and the outer peripheral surface 160b of the convex portion 160, and the diameter Because the surface pressure required for fluid sealing is effectively generated in the radial direction there, creep of the synthetic resin (joint body) due to high-temperature applications occurs, or the nut member 50 is loosened due to vibration or the like. Even if this occurs, high pull-out resistance and good sealing properties can be maintained.

なお、本実施形態では、凸部１６０によるフレア部１４の凹部１７０への押し込み、つまりフレア部１４の厚み方向への屈曲を適正に行えるよう、凸部１６０の先端部内外周と凹部７０の開口部内外周には押し込みガイドとしての丸みを付けたり、テーパーを付けている。 In the present embodiment, the inner periphery of the distal end of the convex portion 160 and the opening of the concave portion 70 are appropriately pressed by the convex portion 160 so that the flare portion 14 can be pushed into the concave portion 170, that is, the flare portion 14 can be bent in the thickness direction. The inner and outer peripheries are rounded or tapered as a push-in guide.

本発明の一実施の形態に係る管継手の断面図である。It is sectional drawing of the pipe joint which concerns on one embodiment of this invention. 図１の要部拡大片側断面図である。It is a principal part expanded one side sectional view of FIG. 本発明の他の実施の形態に係る管継手の要部片側断面図である。It is principal part half sectional drawing of the pipe joint which concerns on other embodiment of this invention. 図３の要部拡大分解図である。It is a principal part expansion exploded view of FIG.

符号の説明Explanation of symbols

１０チューブ
１１非拡径部
１２テーパー段差部
１３拡径部
１４フレア部
２０，２１管継手
３０継手本体
３２第１雄ネジ部（チューブ接続端部）
３６受圧端壁
３７インナ筒部
３８テーパー部
５０ナット部材
５１ナット部
５２押圧端壁
５３チューブ挿入孔
５４段差部
５５エッジ部
６０，１６０凸部
７０，１７０凹部 DESCRIPTION OF SYMBOLS 10 Tube 11 Non-expanded diameter part 12 Taper level | step difference part 13 Expanded diameter part 14 Flare part 20, 21 Pipe joint 30 Joint main body 32 1st male thread part (tube connection end part)
36 pressure receiving end wall 37 inner cylinder part 38 taper part 50 nut member 51 nut part 52 pressing end wall 53 tube insertion hole 54 step part 55 edge part 60,160 convex part 70,170 concave part

Claims

少なくとも一つの端部に筒状のチューブ接続端部を設けた筒状の継手本体と、該継手本体のチューブ接続端部に接続すべき合成樹脂製のチューブに外嵌され、前記チューブ接続端部に螺合されるナット部材を有し、前記継手本体と前記ナット部材それぞれが合成樹脂で形成され、前記チューブ接続端部が該チューブ接続端部の先端部に該チューブ接続端部の軸線に略垂直な受圧端壁を設けるとともに、該受圧端壁よりさらに軸方向に突出して前記チューブの接続端部が拡径した状態で外嵌するインナ筒部を設け、前記ナット部材が該ナット部材のねじ孔の奥側に該ナット部材の軸線に略垂直な押圧端壁を設けるとともに、該押圧端壁に前記チューブが押圧壁側からねじ孔内に挿入するチューブ挿入孔を設け、軸方向で相対する一対の環状の凸部と凹部のうち、一方を前記受圧端壁に設け、他方を前記押圧端壁に設け、前記受圧端壁と前記押圧端壁の間で、前記チューブの拡径部の端部がさらにフレア角度略９０度でフレアし、かつ、厚み方向に屈曲した状態で挟持することを特徴とする管継手。 A tubular joint body provided with a tubular tube connection end at at least one end, and a tube made of synthetic resin to be connected to the tube connection end of the joint body, the tube connection end Each of the joint body and the nut member is formed of a synthetic resin, and the tube connection end is substantially at the tip of the tube connection end and the axis of the tube connection end. A vertical pressure-receiving end wall is provided, and an inner cylindrical portion that protrudes further in the axial direction from the pressure-receiving end wall and fits outside in a state in which the connecting end portion of the tube is expanded is provided, and the nut member is a screw of the nut member A pressing end wall substantially perpendicular to the axis of the nut member is provided on the back side of the hole, and a tube insertion hole is provided on the pressing end wall so that the tube is inserted into the screw hole from the pressing wall side. A pair of annular convex And one of the recesses is provided on the pressure receiving end wall, the other is provided on the pressing end wall, and the end portion of the expanded diameter portion of the tube further has a flare angle between the pressure receiving end wall and the pressing end wall. A pipe joint characterized by flaring at 90 degrees and sandwiched in a bent state in the thickness direction.

前記インナ筒部が該インナ筒部の先端部外面にテーパー部を設け、前記チューブ挿入孔が前記チューブの接続端部が拡径した状態で内嵌するための段差部を設け、該段差部の内径に前記チューブの非拡径部より拡径部にかかる段差部を前記テーパー部に押し付けるエッジ部を設ける請求項１に記載の管継手。 The inner cylinder part is provided with a tapered part on the outer surface of the tip part of the inner cylinder part, the tube insertion hole is provided with a step part for fitting in a state where the diameter of the connection end part of the tube is expanded, and the step part 2. The pipe joint according to claim 1, wherein an edge portion is provided on the inner diameter to press a step portion applied to the expanded diameter portion from the non-expanded portion of the tube against the tapered portion.

前記継手本体と前記ナット部材それぞれがフッ素樹脂で形成されている請求項１又は２に記載の管継手。 The pipe joint according to claim 1 or 2, wherein each of the joint body and the nut member is formed of a fluororesin.