JP3602580B2

JP3602580B2 - Flexible tube for endoscope and method of manufacturing the same

Info

Publication number: JP3602580B2
Application number: JP26513694A
Authority: JP
Inventors: 明浩大久保; 聡古海; 靖町田
Original assignee: Olympus Corp
Current assignee: Olympus Corp
Priority date: 1994-10-28
Filing date: 1994-10-28
Publication date: 2004-12-15
Anticipated expiration: 2019-12-15
Also published as: JPH08122656A

Description

【０００１】
【産業上の利用分野】
本発明は例えば医療用等として用いられる内視鏡挿入部に於ける内視鏡用可撓管及びその製造方法に関する。
【０００２】
【従来の技術】
一般に、例えば医療用等として用いられる内視鏡の挿入部には自由に変形可能な可撓管が配設されている。この種の内視鏡用可撓管の従来技術としては例えば特公昭６３−２４３８０号公報のように金属螺旋管の外周面に網状管が密接状態で被せられて可撓性を有する可撓管素材が形成されるとともに、この可撓管素材の外周面に、熱可塑性チューブを外装した後、可撓管素材および熱可塑性チューブをその軸線を回転中心として回転させながら熱可塑性チューブをその軟化点温度以上に加熱してこのチューブを溶かすことにより、熱可塑性チューブを可撓管素材の内部に浸入させる状態で溶け込ませ、熱可塑性チューブを可撓管素材の外周面に被覆層として密着固定させて一体化させるようにした構成のものがある。
【０００３】
また、内視鏡用可撓管の製造時には熱可塑性チューブが外装された可撓管素材の管内に金属棒を嵌入してこの金属棒に可撓管素材を固定し、この金属棒を軸として可撓管素材および熱可塑性チューブを回転させながら熱可塑性チューブを加熱するようになっている。
【０００４】
【発明が解決しようとする課題】
上記従来構成のものにあっては内視鏡用可撓管の製造時に熱可塑性チューブをその軟化点温度以上に加熱した際に熱可塑性チューブ全体が加熱されるので、熱可塑性チューブがその内周面のみにとどまらず外周面迄も溶融してしまう問題がある。そのため、加熱中の熱可塑性チューブが重力方向にタレ出し、この熱可塑性チューブの外周面にシワが発生したり、溶融樹脂材料をチューブの内周面側へ押し込む方向に加圧され、可撓管素材の内周面への浸み込みにつながるおそれがあるので、加熱前は均一な円筒状の熱可塑性チューブでもその形状を維持できなくなり、加熱後は不均一な円筒形状になる問題がある。
【０００５】
なお、熱可塑性チューブの加熱中、たとえ金属棒が可撓管素材の管内に嵌入されていてもこの金属棒によって熱可塑性チューブの溶融樹脂材料が可撓管素材の網状管から螺旋管に迄、浸み込むことを防ぐことはできないので、製造された内視鏡用可撓管の可撓性が不均一になったり、この可撓管の内径寸法を設計通り確保することができなくなるおそれがある。その結果、内視鏡用可撓管の体腔内への挿入性が悪くなるとともに、可撓管の劣化を早める原因ともなり、耐久性の面でも問題がある。
【０００６】
さらに、内視鏡用可撓管の製造時に可撓管素材および熱可塑性チューブを回転させながら熱可塑性チューブを加熱する方法では熱可塑性チューブの外周面側から先に溶融され、流れ始めるので、熱可塑性チューブのチューブ樹脂層の外径寸法が模様状に不均一になり易く、熱可塑性チューブの外周面の外観が損なわれる問題がある。
【０００７】
この発明は上記事情に着目してなされたもので、その目的は、簡単な構造及び製法で、外皮と可撓管素材との密着性を高め、均一な可撓性が得られ、体腔内への挿入性及び耐久性を向上させることができる内視鏡用可撓管及びその製造方法を提供することにある。
【０００８】
【課題を解決するための手段及び方法】
請求項１の発明は、条帯を螺旋状に巻いて形成された螺旋管と、その外周を覆う網状管とからなる可撓管素材の外周面に熱可塑性プラスチック製の外皮が被覆された内視鏡挿入部の外周を構成する内視鏡用可撓管において、前記外皮の外表面に前記外皮の本体内部の融点よりも融点が高い高融点層を設けたことを特徴とする内視鏡用可撓管である。
【０００９】
請求項２の発明は、外皮本体の外表面にこの外皮の本体内部の融点よりも融点が高い高融点層が設けられた熱可塑性プラスチック製の外皮を、条帯を螺旋状に巻いて形成された螺旋管と、その外周を覆う網状管とからなる可撓管素材の外周面に被覆させたのち、前記外皮の本体内部の軟化点温度以上の加熱温度で加熱することにより、前記外皮を前記網状管と密着一体化させる工程を設けたことを特徴とする内視鏡用可撓管の製造方法である。
請求項３の発明は、前記外皮の本体内部の軟化点温度以上の加熱温度が、融点に対し０乃至＋５０°Ｃの温度範囲内であることを特徴とする、請求項２に記載の内視鏡用可撓管の製造方法である。
【００１０】
【作用】
請求項１の発明では内視鏡用可撓管の製造時に熱可塑性プラスチック製の外皮を加熱した際に、外皮の外表面の高融点層によって外皮の外表面が溶融することを防止することにより、外皮の外表面は元の外観を維持したままの状態で、外皮の本体内部のみを溶かして可撓管素材の外周面に一体的に密着固定するようにしたものである。
【００１１】
請求項２の発明では外皮本体の外表面にこの外皮の本体内部の融点よりも融点が高い高融点層が設けられた熱可塑性プラスチック製の外皮を可撓管素材の外周面に被覆させたのち、外皮の本体内部の融点の−３０℃乃至＋５０℃の温度範囲内で加熱して外皮を網状管と密着一体化させることにより、内視鏡用可撓管の製造時に外皮の外表面は元の外観を維持したままの状態で、外皮の本体内部のみを溶かして可撓管素材の外周面に一体的に密着固定し、外皮の外表面でシワやタレの発生することなく、簡単に均一に、加熱溶着できるようにしたものである。
【００１２】
【実施例】
以下、本発明の第１の実施例を図１および図２を参照して説明する。図１は医療用等として用いられる内視鏡挿入部に於ける内視鏡用可撓管１の要部構成を示すものである。この可撓管１は例えば金属製のリボン状の条帯を螺旋状に巻いて形成された螺旋管２と、その外周を覆う網状管３とからなる可撓管素材４の外周面に熱可塑性プラスチック（熱可塑性エラストマー）製の外皮５が被覆されて形成されている。
【００１３】
また、可撓管１としての硬さや、しなやかさ及び水密性等を決定する外皮５の外表面には図２に示すようにこの外皮５の本体内部の融点よりも融点が高いコート層（高融点層）６が設けられている。このコート層６は熱硬化型又は湿気硬化型等の耐熱性や耐薬性等を良くする材料からなるもので、このコート層６の溶融温度又は劣化温度は外皮５のそれよりも高くなっている。
【００１４】
そして、内視鏡用可撓管１の製造時には可撓管素材４の外周面に熱可塑性プラスチック製の外皮５およびコート層６が被覆された状態で、外皮５の軟化点温度以上、例えば外皮５の融点に対し、０〜＋５０℃の加熱温度で、１０分〜５時間程度加熱される。このとき、コート層６は元の状態を保持したままであり、それとは別に外皮５は溶融状態となる。そのため、外皮５の内周面は網状管３に溶着され、外皮５の内周面と網状管３の外周面とが密着されて一体化される。
【００１５】
ここで、可撓管１の加熱温度は高い程加熱時間は短くて良い。また、可撓管１の加熱温度としては外皮５の融点に対し、−３０℃までは加熱時間を長く、例えば５〜１５時間程度にすることにより外皮５の内周面と網状管３の外周面とを一体化することができる。
【００１６】
そこで、上記構成のものにあっては次の効果を奏する。すなわち、可撓管１の製造時に外皮５の軟化点温度以上の加熱温度で、１０分〜５時間程度可撓管１を加熱した際に、外皮５を覆うコート層６が加熱後も溶融しない為、可撓管１の外表面は元の外観を維持したまま、外皮５のみを可撓管素材４の網状管３と均一に密着一体化できる。そのため、可撓管１の外周面にシワが発生したり、模様状に不均一になることを外皮５の外側のコート層６によって防止することができるので、可撓管１の外周面の外観が損なわれることを防止できるとともに、可撓管１の体腔内への挿入性が悪くなることを防止することができる。
【００１７】
さらに、加熱中、可撓管１の外表面を均一な状態で維持させることができるので、可撓管１の加熱中にこの可撓管１の内部側にムリな押圧力が加わるおそれがない。そのため、コート層６の内側の外皮５の溶融樹脂も可撓管素材４の内部側に浸み込むことはないので、この可撓管１の内径寸法が小さくなるおそれがなく、従来のように加熱前は均一な円筒状の可撓管１が加熱後、不均一な円筒形状に変形することを防止することができる。したがって、可撓管１全体の均一な可撓性が得られる。
【００１８】
また、可撓管１の外皮５の内周面と可撓管素材４の網状管３の外周面との接合面全面を均一に密着一体化できるので、外皮５と可撓管素材４との密着性を高めるとともに、可撓管１の劣化を防止して耐久性の向上を図ることができる。
【００１９】
尚、この第１の実施例に於て、可撓管素材４の外周面に外皮５を配設する方法としては、予め熱可塑性エラストマーから成る外皮５のチューブを作り、それを可撓管素材４の外周面に被覆しても良いし、また押出成形により、可撓管素材４の外周面に、外皮５の成形素材である熱可塑性エラストマーを被覆成形しても良い。
【００２０】
又、コート層６は外皮５のチューブを作る段階で、ディッピング等の方法で外皮５の外周面に配設しても良いし、可撓管素材４の外周面に外皮５のチューブを被覆後にこの外皮５の外周面に同様にディッピング等の方法で配設しても良い。
【００２１】
又、上記第１の実施例では可撓管素材４に１重巻きの螺旋管２を使用した構成のものを示したが、図３に示すように可撓管素材４に内側の第１の螺旋管２ａの外側に第２の螺旋管２ｂを配設させた２重巻き構造の螺旋管２や、３重巻き構造の螺旋管２を使用してもよく、この場合には捩り等による耐性の向上と、可撓管１のトルク追従性を向上させることができる。
【００２２】
ここで、２重巻き、３重巻き構造の螺旋管２はその多層巻き構造の螺旋管２のいずれか１層のリボン帯の厚みを厚くすることにより、本来１重巻き構造の螺旋管２の持つバネ性を保持したまま、２重巻き構造、３重巻き構造で得られる前記のような性能を付与することができる。
【００２３】
又、２重巻き、３重巻き構造にした場合のリボン帯の厚みの厚い螺旋管２ａと薄い螺旋管２ｂとの厚さ差は、０．０５〜０．３ｍｍ位が最良である。又、多層巻き構造の螺旋管２のリボン帯は厚さに限らず、材質を変えたものでも良い。
【００２４】
また、図４は本発明の第２の実施例を示すものである。これは、可撓管１の可撓管素材４の外周面に被覆させた外皮５の本体１１の外表面に、後処理により架橋反応を起こさせ、熱硬化性を付与させることにより、外皮本体１１の内側部分１１ａの融点よりも融点が高い高融点層１１ｂを設けたものである。この場合、外皮本体１１における高融点層１１ｂ以外の内側部分１１ａは元の熱可塑性エラストマーのままで保持されている。そして、外皮本体１１の高融点層１１ｂは内側部分１１ａより溶融温度は高くなっている。
【００２５】
そして、内視鏡用可撓管１の製造時には内側部分１１ａの外表面に高融点層１１ｂが設けられた外皮本体１１が可撓管素材４の外周面に被覆された状態で、この外皮５の内側部分１１ａの融点に対し、０〜＋５０℃の加熱温度で、１０分〜５時間程度加熱される。このとき、高融点層１１ｂは予め熱硬化性を付与されているので、元の状態を保持したままであり、外皮本体１１の内側部分１１ａのみが溶融状態となる。そのため、この外皮本体１１の内側部分１１ａの内周面が網状管３に溶着され、外皮本体１１の内側部分１１ａの内周面と網状管３の外周面とが密着されて一体化される。ここでも、可撓管１の加熱温度は高い程加熱時間は短くて良い。
【００２６】
そこで、上記構成のものにあっては次の効果を奏する。すなわち、可撓管１の製造時に外皮本体１１の内側部分１１ａの軟化点温度以上の加熱温度で、１０分〜５時間程度可撓管１を加熱した際に、外皮本体１１の内側部分１１ａを覆う高融点層１１ｂが加熱後も溶融しない為、可撓管１の外表面は元の外観を維持したまま、外皮本体１１の内側部分１１ａのみを可撓管素材４の網状管３と均一に密着一体化できる。そのため、第１の実施例と同様に可撓管１の外周面にシワが発生したり、模様状に不均一になることを外皮本体１１の外側の高融点層１１ｂによって防止することができるので、可撓管１の外周面の外観が損なわれることを防止できるとともに、可撓管１の体腔内への挿入性が悪くなることを防止することができる。
【００２７】
また、加熱中、可撓管１の外表面を均一な状態で維持させることができ、可撓管１の加熱中にこの可撓管１の内部側にムリな押圧力が加わるおそれがないので、外皮本体１１における高融点層１１ｂの内側部分１１ａの溶融樹脂も可撓管素材４の内部側に浸み込むことはなく、この可撓管１の内径寸法が小さくなるおそれがない。そのため、従来のように加熱前は均一な円筒状の可撓管１が加熱後、不均一な円筒形状に変形することを防止することができるので、可撓管１全体の均一な可撓性が得られるとともに、可撓管１の外皮本体１１の内側部分１１ａの内周面と可撓管素材４の網状管３の外周面との接合面全面を均一に密着一体化できるので、外皮５と可撓管素材４との密着性を高めるとともに、可撓管１の劣化を防止して耐久性の向上を図ることができる。
【００２８】
また、本実施例では特に外皮本体１１の外表面に、後処理により架橋反応を起こさせ、熱硬化性を付与したため、熱硬化性の特徴である耐熱性、耐薬性等を向上させることができる。ここで、外皮本体１１の高融点層１１ｂは架橋前は、熱可塑性エラストマーである為、成形性が良く、簡単に任意のチューブ加工又は、可撓管素材４の外周面への被覆が可能である。
【００２９】
また、図５は本発明の第３の実施例を示すものである。これは、螺旋管２と網状管３からなる可撓管素材４の外周面に架橋剤を含有させた外皮本体２１を被覆状態で配設し、この外皮本体２１の外表面に、後処理により外皮本体２１の内側部分２１ａの融点よりも融点が高い高融点層２１ｂを設けたものである。
【００３０】
ここで、外皮本体２１は、成形前の熱可塑性エラストマーに架橋剤を添加したのち、網状管３の外周面に押出し成形等の手段により被覆したものである。そして、この外皮本体２１の押出し成形後、８０℃〜１２０℃の加熱温度で、１〜１２時間熱処理することにより、外皮本体２１の表面より架橋反応が起こり、この外皮本体２１の外表面に、熱硬化性が付与されて高融点層２１ｂが形成されるようになっている。これにより、外皮本体２１の表面の高融点層２１ｂは、内側部分２１ａより溶融温度が高くなる。
【００３１】
そして、内視鏡用可撓管１の製造時には予め上述した方法により、外皮本体２１の外表面に熱硬化性が付与された高融点層２１ｂが形成されたのち、この外皮本体２１の内側部分２１ａの融点に対し、０〜＋５０℃の加熱温度で、１０分〜５時間程度加熱される。このとき、高融点層２１ｂは予め熱硬化性を付与されているので、元の状態を保持したままであり、外皮本体２１の内側部分２１ａのみが溶融状態となる。そのため、この外皮本体２１の内側部分２１ａの内周面が網状管３に溶着され、外皮本体２１の内側部分２１ａの内周面と網状管３の外周面とが密着されて一体化される。ここでも、可撓管１の加熱温度は高い程加熱時間は短くて良い。
【００３２】
そこで、上記構成のものにあっても第１の実施例と同様、可撓管１の製造時に外皮本体２１の内側部分２１ａの軟化点温度以上の加熱温度で、１０分〜５時間程度可撓管１を加熱した際に、外皮本体２１の内側部分２１ａを覆う高融点層２１ｂが加熱後も溶融しない為、可撓管１の外表面は元の外観を維持したまま、外皮本体２１の内側部分２１ａのみを可撓管素材４の網状管３と均一に密着一体化できる。そのため、第１の実施例と同様に可撓管１の外周面にシワが発生したり、模様状に不均一になることを外皮本体２１の外側の高融点層２１ｂによって防止することができるので、可撓管１の外周面の外観が損なわれることを防止できるとともに、可撓管１の体腔内への挿入性が悪くなることを防止することができる。
【００３３】
また、加熱中、可撓管１の外表面を均一な状態で維持させることができ、可撓管１の加熱中にこの可撓管１の内部側にムリな押圧力が加わるおそれがないので、外皮本体２１における高融点層２１ｂの内側部分２１ａの溶融樹脂も可撓管素材４の内部側に浸み込むことはなく、この可撓管１の内径寸法が小さくなるおそれがない。そのため、従来のように加熱前は均一な円筒状の可撓管１が加熱後、不均一な円筒形状に変形することを防止することができるので、可撓管１全体の均一な可撓性が得られる。さらに、可撓管１の外皮本体２１の内側部分２１ａの内周面と可撓管素材４の網状管３の外周面との接合面全面を均一に密着一体化できるので、外皮５と可撓管素材４との密着性を高めるとともに、可撓管１の劣化を防止して耐久性の向上を図ることができる。
【００３４】
また、外皮本体２１を網状管３の外周面に押出し成形等の手段により被覆したのち、その後処理により、外皮本体２１の外表面に熱硬化性を付与して高融点層２１ｂを形成することができるので、第２の実施例と同様に高融点層２１ｂの成形前に熱可塑性エラストマーである外皮本体２１を網状管３の外周面に被覆することができる。そのため、外皮本体２１の成形性が良く、簡単に任意のチューブ加工又は、可撓管素材４の外周面への被覆が可能である。尚、第３の実施例の方法は、チューブを成形する段階で用いても良い。
【００３５】
また、図６は本発明の第４の実施例を示すものである。これは、螺旋管２と網状管３からなる可撓管素材４の外周面に外皮５を配設したのち、この外皮５の外周面にこの外皮５よりも融点の高い被覆チューブ（高融点層）３１を被覆したものである。ここで、外皮５としては、熱可塑性エラストマーを用いることができる。また、被覆チューブ３１としては、ＦＥＰ，ＰＦＡ，ＰＴＦＥ，Ｓｉ等のチューブが良い。さらに、被覆作業のやり易さを向上する為には、被覆チューブ３１として熱収縮チューブを用いても良い。
【００３６】
そして、内視鏡用可撓管１の製造時には可撓管素材４の外周面に熱可塑性プラスチック製の外皮５が被覆されたのち、この外皮５の外周面に被覆チューブ３１が被覆された状態で、外皮５の融点に対し、０〜＋５０℃の加熱温度で、１０分〜５時間程度加熱される。このとき、被覆チューブ３１は元の状態を保持したままであり、外皮５のみが溶融状態となる。そのため、この外皮５の内周面が網状管３に溶着され、外皮５の内周面と網状管３の外周面とが密着されて一体化される。ここでも、可撓管１の加熱温度は高い程加熱時間は短くて良い。なお、加熱後は、外皮５の融点より低くしてから被覆チューブ３１を剥がす。
【００３７】
そこで、上記構成のものにあっては次の効果を奏する。すなわち、可撓管１の製造時に外皮５の軟化点温度以上の加熱温度で、１０分〜５時間程度可撓管１を加熱した際に、外皮５を覆う被覆チューブ３１が加熱後も溶融しない為、可撓管１の外表面は元の外観を維持したまま、外皮５のみを溶融させて可撓管素材４の網状管３と均一に密着一体化できる。
【００３８】
さらに、本実施例では特に外皮５の全周に渡り、被覆チューブ３１が均一に覆っているので、被覆チューブ３１の内周面の均一さが外皮５の外周面に転写される。そのため、第１の実施例と同様に可撓管１の外周面にシワが発生したり、模様状に不均一になることを外皮５の外側の被覆チューブ３１によって防止することができ、被覆チューブ３１を剥がした際に、可撓管１の外観を格段と向上させることができるとともに、可撓管１の体腔内への挿入性が悪くなることを防止することができる。
【００３９】
また、加熱中、可撓管１の外表面を均一な状態で維持させることができ、可撓管１の加熱中にこの可撓管１の内部側にムリな押圧力が加わるおそれがないので、被覆チューブ３１の内側の外皮５の溶融樹脂も可撓管素材４の内部側に浸み込むことはなく、この可撓管１の内径寸法が小さくなるおそれがない。そのため、従来のように加熱前は均一な円筒状の可撓管１が加熱後、不均一な円筒形状に変形することを防止することができるので、可撓管１全体の均一な可撓性が得られる。さらに、可撓管１の外皮５の内周面と可撓管素材４の網状管３の外周面との接合面全面を均一に密着一体化できるので、外皮５と可撓管素材４との密着性を高めるとともに、可撓管１の劣化を防止して耐久性の向上を図ることができる。
【００４０】
なお、本発明は上記実施例に限定されるものではなく、本発明の要旨を逸脱しない範囲で種々変形実施できることは勿論である。
次に、本出願の他の特徴的な技術事項を下記の通り付記する。
【００４１】
記
（付記項１）条帯を螺旋状に巻いて形成された螺旋管とその外周を覆う網状管からなる可撓管素材の外周を熱可塑性プラスチック製の外皮で被覆した内視鏡可撓管において、前記外皮の外表面の融点を外皮内部本体の融点よりも高く形成したことを特徴とする内視鏡用可撓管。
【００４２】
（付記項２）外皮の外表面の融点を外皮内部本体の融点よりも高く形成し、外皮内部本体の融点の−３０乃至＋５０℃の温度範囲内で加熱することにより前記外皮が網状管と密着一体化された付記項１に記載の内視鏡用可撓管の製造方法。
【００４３】
（付記項３）外皮の外表面の融点を外皮の融点よりも高い被覆材で覆い、外皮内部本体の融点の−３０乃至＋５０℃の温度範囲内で加熱した後に前記被覆材を除去することにより前記外皮が網状管と密着一体化された内視鏡用可撓管の製造方法。
【００４４】
（付記項４）リボン状の条帯を螺旋状に巻いて形成される可撓性の螺旋管とその外側を覆う網状管と熱可塑性プラスチックから成る外皮から構成されている内視鏡用可撓管において、外皮素材の外表面の融点を内面よりも高くしたことを特徴とする内視鏡用可撓管。
【００４５】
（付記項５）外皮部はチューブから成ることを特徴とする付記項４の内視鏡用可撓管。
（付記項６）外皮部は熱可塑性プラスチックを押出し成形により、網状管の外面に被覆したことを特徴とする付記項４の内視鏡用可撓管。
【００４６】
（付記項７）外皮部表面は熱硬化又は湿気硬化のコーティングを施すことを特徴とする付記項４の内視鏡用可撓管。
（付記項８）外皮部表面は後処理にて架橋させ、熱硬化性を具備させたことを特徴とする付記項４の内視鏡用可撓管。
【００４７】
（付記項９）チューブから成る外皮部を螺旋管と網状管から成る構成部材の外周面に被覆後、外皮部内面素材の融点より−３０〜＋５０℃の温度で加熱することにより、網状管と一体化したことを特徴とする内視鏡用可撓管の製造方法。
【００４８】
（付記項１０）螺旋管と網状管から成る構成部材外面に外皮部を設けた後、外面を融点の高いチューブで被覆し、その後、外皮部素材の融点より−３０〜＋５０℃の温度で加熱した後、被覆してあったチューブを取り除くことにより、外皮部と網状管を一体化することを特徴とする内視鏡用可撓管の製造方法。
【００４９】
（付記項１１）被覆チューブはＦＥＰ，ＰＦＡ，ＰＴＦＥ，Ｓｉ等の高融点素材から成ることを特徴とする付記項１０の内視鏡用可撓管の製造方法。
（付記項１２）外皮部チューブは硬さの異なるチューブを継ぎ合わせたことを特徴とする付記項４，５の内視鏡用可撓管。
（付記項１３）外皮部は硬さの異なる熱可塑性プラスチックを押出し成形により網状管の外面に被覆したことを特徴とする付記項４，６の内視鏡用可撓管。
【００５０】
【発明の効果】
この発明によれば簡単な構造及び製法で、外皮と可撓管素材との密着性を高め、均一な可撓性が得られ、体腔内への挿入性及び耐久性を向上させることができる。
【図面の簡単な説明】
【図１】本発明の第１の実施例の内視鏡用可撓管の要部を断面にして示す側面図。
【図２】可撓管の要部構成を示す縦断面図。
【図３】第１の実施例の可撓管素材の変形例を示す要部の縦断面図。
【図４】本発明の第２の実施例の内視鏡用可撓管の要部構成を示す縦断面図。
【図５】本発明の第３の実施例の内視鏡用可撓管の要部構成を示す縦断面図。
【図６】本発明の第４の実施例の内視鏡用可撓管の要部構成を示す縦断面図。
【符号の説明】
２…螺旋管、３…網状管、４…可撓管素材、５…外皮、６，１１ｂ，２１ｂ…高融点層、３１…被覆チューブ（高融点層）。[0001]
[Industrial applications]
The present invention relates to a flexible tube for an endoscope in an endoscope insertion portion used for medical use, for example, and a method for manufacturing the same.
[0002]
[Prior art]
In general, a flexible tube that can be freely deformed is provided in an insertion portion of an endoscope used for medical use, for example. As a prior art of this type of flexible tube for an endoscope, for example, as disclosed in Japanese Patent Publication No. Sho 63-24380, a flexible tube in which a braided tube is covered closely on the outer peripheral surface of a metal spiral tube. After the material is formed, a thermoplastic tube is provided on the outer peripheral surface of the flexible tube material, and then the thermoplastic tube is softened to its softening point while rotating the flexible tube material and the thermoplastic tube around the axis thereof. By heating the tube to a temperature or more to melt the tube, the thermoplastic tube is melted in a state of infiltration into the inside of the flexible tube material, and the thermoplastic tube is tightly fixed as a coating layer on the outer peripheral surface of the flexible tube material. There is a configuration in which they are integrated.
[0003]
Further, at the time of manufacturing the flexible tube for an endoscope, a metal rod is fitted into a tube of a flexible tube material provided with a thermoplastic tube, and the flexible tube material is fixed to the metal rod. The thermoplastic tube is heated while rotating the flexible tube material and the thermoplastic tube.
[0004]
[Problems to be solved by the invention]
In the above-mentioned conventional configuration, when the thermoplastic tube is heated to its softening point temperature or more during the production of the flexible tube for an endoscope, the entire thermoplastic tube is heated. There is a problem that not only the surface but also the outer peripheral surface is melted. Therefore, the thermoplastic tube being heated sags in the direction of gravity, and wrinkles are generated on the outer peripheral surface of the thermoplastic tube, or the thermoplastic resin is pressed in a direction of pushing the molten resin material toward the inner peripheral surface of the tube, and the flexible tube is pressed. Since there is a possibility that the raw material may permeate into the inner peripheral surface, even if it is a uniform cylindrical thermoplastic tube before heating, the shape cannot be maintained, and after heating, there is a problem that the cylindrical shape becomes uneven.
[0005]
During the heating of the thermoplastic tube, even if the metal rod is fitted into the tube of the flexible tube material, the molten metal material of the thermoplastic tube is changed from the mesh tube of the flexible tube material to the spiral tube by this metal rod. Since it is impossible to prevent infiltration, there is a possibility that the flexibility of the manufactured flexible tube for an endoscope becomes uneven or the inner diameter of the flexible tube cannot be secured as designed. is there. As a result, the insertability of the flexible tube for the endoscope into the body cavity is deteriorated, and the deterioration of the flexible tube may be accelerated, and there is a problem in durability.
[0006]
Further, in the method of heating the thermoplastic tube while rotating the flexible tube material and the thermoplastic tube at the time of manufacturing the flexible tube for an endoscope, the outer peripheral surface side of the thermoplastic tube is melted first and starts to flow. There is a problem that the outer diameter of the tube resin layer of the plastic tube tends to be non-uniform in a pattern, and the appearance of the outer peripheral surface of the thermoplastic tube is impaired.
[0007]
The present invention has been made with a focus on the above circumstances, and its purpose is to improve the adhesion between the outer cover and the flexible tube material with a simple structure and manufacturing method, to obtain uniform flexibility, and to enter the body cavity. It is an object of the present invention to provide a flexible tube for an endoscope which can improve the insertability and durability of a tube, and a method for manufacturing the same.
[0008]
Means and method for solving the problem
According to the first aspect of the present invention, there is provided a flexible tube material comprising a spiral tube formed by spirally winding a strip and a braided tube covering the outer periphery thereof, in which an outer peripheral surface of a thermoplastic plastic is coated on an outer peripheral surface . A flexible tube for an endoscope constituting an outer periphery of an endoscope insertion portion , wherein a high melting point layer having a melting point higher than a melting point inside a main body of the outer cover is provided on an outer surface of the outer cover. Flexible tube.
[0009]
The invention of claim 2, the outer skin is higher melting point than the outer skin of the inner body melting the outer surface refractory layer is made of thermoplastic plastic which is provided in the outer skin body, formed by winding a strip helically Spiral tube, and after covering the outer peripheral surface of a flexible tube material consisting of a mesh tube covering the outer periphery, by heating at a heating temperature equal to or higher than the softening point temperature inside the main body of the outer cover, the outer cover is A method of manufacturing a flexible tube for an endoscope, comprising a step of closely attaching and integrating with a reticulated tube.
The invention according to claim 3 is characterized in that the heating temperature equal to or higher than the softening point temperature inside the main body of the outer skin is within a temperature range of 0 to + 50 ° C with respect to the melting point. 3 is a method for manufacturing a flexible tube for a mirror.
[0010]
[Action]
According to the first aspect of the present invention, when the outer shell made of thermoplastic is heated at the time of manufacturing the flexible tube for an endoscope, the outer surface of the outer shell is prevented from melting by the high melting point layer on the outer surface of the outer shell. The outer surface of the outer skin is maintained in its original appearance, and only the inside of the main body of the outer skin is melted and integrally fixed to the outer peripheral surface of the flexible tube material.
[0011]
According to the second aspect of the invention, the outer peripheral surface of the flexible tube material is coated with a thermoplastic outer shell having a high melting point layer having a melting point higher than the melting point inside the outer shell main body provided on the outer surface of the outer shell main body. The outer surface of the outer skin is kept intact when the flexible tube for an endoscope is manufactured by heating the inner skin to a temperature within the range of −30 ° C. to + 50 ° C., which is the melting point inside the outer shell body, to tightly integrate the outer skin with the mesh tube. While maintaining the external appearance of the outer shell, only the inside of the outer shell is melted and tightly fixed to the outer peripheral surface of the flexible tube material.Easily uniform without wrinkles or sagging on the outer surface of the outer shell And heat welding.
[0012]
【Example】
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a configuration of a main part of an endoscope flexible tube 1 in an endoscope insertion portion used for medical use or the like. The flexible tube 1 has a thermoplastic tube material 4 composed of a spiral tube 2 formed by, for example, spirally winding a metal ribbon strip and a mesh tube 3 covering the outer periphery thereof. An outer skin 5 made of plastic (thermoplastic elastomer) is covered and formed.
[0013]
Further, as shown in FIG. 2, a coat layer having a melting point higher than the melting point inside the main body of the outer skin 5 is formed on the outer surface of the outer skin 5 which determines the hardness, flexibility, watertightness and the like of the flexible tube 1 as shown in FIG. A melting point layer 6 is provided. The coating layer 6 is made of a material such as a thermosetting type or a moisture-curing type that improves heat resistance, chemical resistance, and the like. The melting temperature or the deterioration temperature of the coating layer 6 is higher than that of the outer skin 5. .
[0014]
At the time of manufacturing the flexible tube 1 for an endoscope, the outer peripheral surface of the flexible tube material 4 is covered with a thermoplastic resin outer cover 5 and a coat layer 6 and the softening point temperature of the outer cover 5 or more, for example, the outer cover For a melting point of 5, heating is performed at a heating temperature of 0 to + 50 ° C. for about 10 minutes to 5 hours. At this time, the coat layer 6 keeps its original state, and the outer skin 5 is in a molten state separately. Therefore, the inner peripheral surface of the outer cover 5 is welded to the mesh tube 3, and the inner peripheral surface of the outer cover 5 and the outer peripheral surface of the mesh tube 3 are tightly integrated.
[0015]
Here, the higher the heating temperature of the flexible tube 1, the shorter the heating time may be. The heating time of the flexible tube 1 is longer than -30 ° C. with respect to the melting point of the outer skin 5. The surface can be integrated.
[0016]
Therefore, the above configuration has the following effects. That is, when the flexible tube 1 is heated at a heating temperature equal to or higher than the softening point temperature of the outer cover 5 for about 10 minutes to 5 hours at the time of manufacturing the flexible tube 1, the coat layer 6 covering the outer cover 5 does not melt even after heating. Therefore, only the outer skin 5 can be uniformly and tightly integrated with the mesh tube 3 of the flexible tube material 4 while maintaining the outer surface of the flexible tube 1 in its original appearance. For this reason, it is possible to prevent wrinkles on the outer peripheral surface of the flexible tube 1 and to make the outer surface of the flexible tube 1 non-uniform in a pattern shape by using the outer coating layer 6. Can be prevented from being damaged, and the insertion property of the flexible tube 1 into the body cavity can be prevented from being deteriorated.
[0017]
Further, since the outer surface of the flexible tube 1 can be maintained in a uniform state during the heating, there is no possibility that a pressing force is applied to the inside of the flexible tube 1 during the heating of the flexible tube 1. . Therefore, since the molten resin of the outer skin 5 inside the coat layer 6 does not permeate into the inside of the flexible tube material 4, there is no possibility that the inner diameter of the flexible tube 1 becomes small. Before heating, the uniform cylindrical flexible tube 1 can be prevented from deforming into an uneven cylindrical shape after heating. Therefore, uniform flexibility of the entire flexible tube 1 can be obtained.
[0018]
Further, since the entire joint surface between the inner peripheral surface of the outer tube 5 of the flexible tube 1 and the outer peripheral surface of the mesh tube 3 of the flexible tube material 4 can be uniformly tightly integrated, the outer skin 5 and the flexible tube material 4 can be joined together. In addition to enhancing the adhesion, the deterioration of the flexible tube 1 can be prevented, and the durability can be improved.
[0019]
In the first embodiment, as a method of disposing the outer cover 5 on the outer peripheral surface of the flexible tube material 4, a tube of the outer cover 5 made of a thermoplastic elastomer is prepared in advance, and the tube is made of the flexible tube material. The outer peripheral surface of the flexible tube material 4 may be covered with a thermoplastic elastomer by extrusion molding.
[0020]
The coat layer 6 may be provided on the outer peripheral surface of the outer cover 5 by dipping or the like at the stage of forming the tube of the outer cover 5, or after the outer peripheral surface of the flexible tube material 4 is covered with the tube of the outer cover 5. Similarly, it may be arranged on the outer peripheral surface of the outer skin 5 by a method such as dipping.
[0021]
In the first embodiment described above, the flexible tube material 4 is constituted by using a single-wound helical tube 2. However, as shown in FIG. A spiral tube 2 having a double winding structure in which a second spiral tube 2b is disposed outside the spiral tube 2a, or a spiral tube 2 having a triple winding structure may be used. And the torque followability of the flexible tube 1 can be improved.
[0022]
Here, the spiral tube 2 having the double winding structure and the triple winding structure is formed by increasing the thickness of the ribbon band of any one layer of the spiral tube 2 having the multilayer winding structure. The above-mentioned performance obtained by the double winding structure and the triple winding structure can be provided while maintaining the spring property.
[0023]
The best difference in thickness between the spiral tube 2a having a large ribbon band thickness and the spiral tube 2b having a thin ribbon band in a double winding or triple winding structure is about 0.05 to 0.3 mm. Further, the ribbon band of the spiral tube 2 having the multilayer winding structure is not limited to the thickness, but may be made of a different material.
[0024]
FIG. 4 shows a second embodiment of the present invention. This is because the outer surface of the main body 11 of the outer cover 5 covering the outer peripheral surface of the flexible tube material 4 of the flexible tube 1 is subjected to a cross-linking reaction by a post-treatment, thereby imparting thermosetting properties. 11 is provided with a high melting point layer 11b having a melting point higher than the melting point of the inner portion 11a. In this case, the inner portion 11a of the outer shell body 11 other than the high melting point layer 11b is held as it is as the original thermoplastic elastomer. The melting point of the high melting point layer 11b of the outer shell main body 11 is higher than that of the inner portion 11a.
[0025]
When the flexible tube 1 for an endoscope is manufactured, the outer shell body 11 in which the high melting point layer 11b is provided on the outer surface of the inner portion 11a is covered with the outer peripheral surface of the flexible tube material 4, and the outer shell 5 is formed. Is heated at a heating temperature of 0 to + 50 ° C. with respect to the melting point of the inner portion 11a for about 10 minutes to 5 hours. At this time, since the high-melting point layer 11b has been given thermosetting properties in advance, the original state is maintained, and only the inner portion 11a of the outer shell main body 11 is in a molten state. Therefore, the inner peripheral surface of the inner portion 11a of the outer shell main body 11 is welded to the mesh tube 3, and the inner peripheral surface of the inner portion 11a of the outer shell body 11 and the outer peripheral surface of the mesh tube 3 are tightly integrated. Here, the heating time may be shorter as the heating temperature of the flexible tube 1 is higher.
[0026]
Therefore, the above configuration has the following effects. That is, when the flexible tube 1 is heated for about 10 minutes to 5 hours at a heating temperature equal to or higher than the softening point temperature of the inner portion 11a of the outer shell body 11 at the time of manufacturing the flexible tube 1, the inner portion 11a of the outer shell body 11 is heated. Since the high melting point layer 11b to be covered does not melt even after heating, only the inner portion 11a of the outer shell body 11 is uniformly formed with the mesh tube 3 of the flexible tube material 4 while maintaining the outer surface of the flexible tube 1 in its original appearance. Can be closely integrated. For this reason, similarly to the first embodiment, the occurrence of wrinkles on the outer peripheral surface of the flexible tube 1 and unevenness in the pattern can be prevented by the high melting point layer 11b outside the outer shell body 11. In addition, the appearance of the outer peripheral surface of the flexible tube 1 can be prevented from being impaired, and the insertion property of the flexible tube 1 into the body cavity can be prevented from being deteriorated.
[0027]
Further, the outer surface of the flexible tube 1 can be maintained in a uniform state during the heating, and there is no possibility that a pressing force is applied to the inner side of the flexible tube 1 during the heating of the flexible tube 1. Also, the molten resin in the inner portion 11a of the high melting point layer 11b in the outer shell body 11 does not seep into the inside of the flexible tube material 4 and the inner diameter of the flexible tube 1 does not decrease. For this reason, it is possible to prevent the uniform cylindrical flexible tube 1 from being deformed into a non-uniform cylindrical shape after heating as in the prior art, so that the uniform flexibility of the entire flexible tube 1 can be prevented. Is obtained, and the entire joint surface between the inner peripheral surface of the inner portion 11a of the outer shell main body 11 of the flexible tube 1 and the outer peripheral surface of the mesh tube 3 of the flexible tube material 4 can be uniformly tightly integrated. The adhesion between the flexible tube 1 and the flexible tube material 4 can be improved, and the deterioration of the flexible tube 1 can be prevented to improve the durability.
[0028]
In addition, in the present embodiment, a cross-linking reaction is caused by the post-treatment particularly on the outer surface of the outer shell main body 11 to impart thermosetting properties, so that heat resistance, chemical resistance, and the like, which are characteristics of thermosetting properties, can be improved. . Here, since the high melting point layer 11b of the outer shell body 11 is a thermoplastic elastomer before cross-linking, it has good moldability and can be easily processed into any tube or coated on the outer peripheral surface of the flexible tube material 4. is there.
[0029]
FIG. 5 shows a third embodiment of the present invention. In this case, an outer shell body 21 containing a cross-linking agent is disposed on the outer peripheral surface of a flexible tube material 4 composed of a spiral tube 2 and a mesh tube 3 in a covered state, and the outer surface of the outer shell body 21 is post-processed. A high melting point layer 21b having a higher melting point than the melting point of the inner portion 21a of the outer shell main body 21 is provided.
[0030]
Here, the outer shell main body 21 is obtained by adding a crosslinking agent to the thermoplastic elastomer before molding, and then coating the outer peripheral surface of the mesh tube 3 by means such as extrusion molding. Then, after the extrusion of the outer shell main body 21, by performing a heat treatment at a heating temperature of 80 ° C. to 120 ° C. for 1 to 12 hours, a crosslinking reaction occurs from the surface of the outer shell main body 21. The thermosetting property is imparted to form the high melting point layer 21b. Thereby, the melting point of the high melting point layer 21b on the surface of the outer shell main body 21 is higher than that of the inner portion 21a.
[0031]
When the flexible tube 1 for an endoscope is manufactured, a high-melting point layer 21b having thermosetting properties is formed on the outer surface of the outer shell body 21 by the above-described method in advance, and then the inner portion of the outer shell body 21 is formed. Heating is performed for about 10 minutes to 5 hours at a heating temperature of 0 to + 50 ° C. with respect to the melting point of 21a. At this time, since the high-melting point layer 21b has been given thermosetting properties in advance, the original state is maintained, and only the inner portion 21a of the outer shell main body 21 is in a molten state. Therefore, the inner peripheral surface of the inner portion 21a of the outer shell main body 21 is welded to the mesh tube 3, and the inner peripheral surface of the inner portion 21a of the outer shell body 21 and the outer peripheral surface of the mesh tube 3 are tightly integrated. Here, the heating time may be shorter as the heating temperature of the flexible tube 1 is higher.
[0032]
Therefore, even in the case of the above-described structure, as in the first embodiment, when the flexible tube 1 is manufactured, the flexible tube 1 is heated at a heating temperature higher than the softening point temperature of the inner portion 21a of the outer casing body 21 for about 10 minutes to 5 hours. When the tube 1 is heated, the high melting point layer 21b covering the inner portion 21a of the outer shell main body 21 does not melt even after the heating, so that the outer surface of the flexible tube 1 is maintained inside the outer shell main body 21 while maintaining the original appearance. Only the portion 21a can be uniformly tightly integrated with the mesh tube 3 of the flexible tube material 4. For this reason, similarly to the first embodiment, the occurrence of wrinkles on the outer peripheral surface of the flexible tube 1 and the unevenness in the pattern can be prevented by the high melting point layer 21b outside the outer shell body 21. In addition, the appearance of the outer peripheral surface of the flexible tube 1 can be prevented from being impaired, and the insertion property of the flexible tube 1 into the body cavity can be prevented from being deteriorated.
[0033]
Further, the outer surface of the flexible tube 1 can be maintained in a uniform state during the heating, and there is no possibility that a pressing force is applied to the inner side of the flexible tube 1 during the heating of the flexible tube 1. Also, the molten resin in the inner portion 21a of the high melting point layer 21b in the outer shell body 21 does not permeate into the inside of the flexible tube material 4 and there is no possibility that the inner diameter of the flexible tube 1 is reduced. For this reason, it is possible to prevent the uniform cylindrical flexible tube 1 from being deformed into a non-uniform cylindrical shape after heating as in the prior art, so that the uniform flexibility of the entire flexible tube 1 can be prevented. Is obtained. Furthermore, since the entire joint surface between the inner peripheral surface of the inner portion 21a of the outer shell main body 21 of the flexible tube 1 and the outer peripheral surface of the mesh tube 3 of the flexible tube material 4 can be evenly adhered and integrated, the outer skin 5 and the flexible member can be flexibly connected. The adhesion to the tube material 4 can be increased, and the deterioration of the flexible tube 1 can be prevented to improve the durability.
[0034]
Further, after the outer shell body 21 is coated on the outer peripheral surface of the mesh tube 3 by means such as extrusion molding or the like, the outer surface of the outer shell body 21 may be subjected to thermosetting to form the high melting point layer 21b by a subsequent treatment. Therefore, the outer shell 21 made of a thermoplastic elastomer can be coated on the outer peripheral surface of the reticulated tube 3 before the formation of the high melting point layer 21b as in the second embodiment. Therefore, the formability of the outer shell main body 21 is good, and it is possible to easily form an arbitrary tube or cover the outer peripheral surface of the flexible tube material 4. The method of the third embodiment may be used at the stage of forming a tube.
[0035]
FIG. 6 shows a fourth embodiment of the present invention. This is achieved by arranging an outer skin 5 on the outer peripheral surface of a flexible tube material 4 composed of a spiral tube 2 and a mesh tube 3 and then coating the outer peripheral surface of the outer tube 5 with a coating tube having a higher melting point than the outer skin 5 (high melting point layer). ) 31. Here, as the outer skin 5, a thermoplastic elastomer can be used. Further, as the coating tube 31, a tube of FEP, PFA, PTFE, Si or the like is preferable. Further, in order to improve the ease of the coating operation, a heat-shrinkable tube may be used as the coating tube 31.
[0036]
When the flexible tube 1 for an endoscope is manufactured, the outer peripheral surface of the flexible tube material 4 is covered with a thermoplastic resin outer cover 5 and then the outer peripheral surface of the outer cover 5 is covered with a covering tube 31. Then, it is heated for about 10 minutes to 5 hours at a heating temperature of 0 to + 50 ° C. with respect to the melting point of the outer skin 5. At this time, the coating tube 31 keeps its original state, and only the outer skin 5 is in a molten state. Therefore, the inner peripheral surface of the outer cover 5 is welded to the mesh tube 3, and the inner peripheral surface of the outer cover 5 and the outer peripheral surface of the mesh tube 3 are tightly integrated. Here, the heating time may be shorter as the heating temperature of the flexible tube 1 is higher. After the heating, the coating tube 31 is peeled off after lowering the melting point of the outer skin 5.
[0037]
Therefore, the above configuration has the following effects. That is, when the flexible tube 1 is heated at a heating temperature equal to or higher than the softening point temperature of the outer cover 5 for about 10 minutes to 5 hours when the flexible tube 1 is manufactured, the covering tube 31 covering the outer cover 5 does not melt even after heating. Therefore, while keeping the outer surface of the flexible tube 1 in its original appearance, only the outer skin 5 is melted, and the flexible tube 1 can be uniformly tightly integrated with the mesh tube 3 of the flexible tube material 4.
[0038]
Furthermore, in the present embodiment, the coating tube 31 covers the entire circumference of the outer skin 5 uniformly, so that the uniformity of the inner peripheral surface of the coating tube 31 is transferred to the outer peripheral surface of the outer skin 5. Therefore, wrinkles on the outer peripheral surface of the flexible tube 1 and non-uniformity in the pattern can be prevented by the coating tube 31 outside the outer skin 5 as in the first embodiment. When the flexible tube 1 is peeled off, the appearance of the flexible tube 1 can be remarkably improved, and the insertion property of the flexible tube 1 into the body cavity can be prevented from being deteriorated.
[0039]
Further, the outer surface of the flexible tube 1 can be maintained in a uniform state during the heating, and there is no possibility that a pressing force is applied to the inner side of the flexible tube 1 during the heating of the flexible tube 1. Also, the molten resin of the outer skin 5 inside the covering tube 31 does not permeate into the inside of the flexible tube material 4, and there is no possibility that the inner diameter of the flexible tube 1 is reduced. For this reason, it is possible to prevent the uniform cylindrical flexible tube 1 from being deformed into a non-uniform cylindrical shape after heating as in the prior art, so that the uniform flexibility of the entire flexible tube 1 can be prevented. Is obtained. Furthermore, since the entire joint surface between the inner peripheral surface of the outer tube 5 of the flexible tube 1 and the outer peripheral surface of the mesh tube 3 of the flexible tube material 4 can be evenly tightly integrated, the outer skin 5 and the flexible tube material 4 can be joined together. In addition to enhancing the adhesion, the deterioration of the flexible tube 1 can be prevented, and the durability can be improved.
[0040]
It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.
Next, other characteristic technical matters of the present application will be additionally described as follows.
[0041]
(Additional Item 1) An endoscope flexible tube in which the outer periphery of a flexible tube material consisting of a spiral tube formed by spirally winding a strip and a mesh tube covering the outer periphery is covered with a thermoplastic plastic outer skin. 2. The flexible tube for an endoscope according to claim 1, wherein the melting point of the outer surface of the outer shell is higher than the melting point of the inner shell inner body.
[0042]
(Additional Item 2) The outer skin is in close contact with the reticulated tube by forming the melting point of the outer surface of the outer shell higher than the melting point of the inner shell body and heating it within the temperature range of −30 to + 50 ° C. of the melting point of the inner shell body. 2. The method for manufacturing an integrated flexible tube for an endoscope according to Additional Item 1.
[0043]
(Supplementary Note 3) By covering the outer surface of the outer skin with a coating material having a melting point higher than the melting point of the outer skin, and removing the coating material after heating within a temperature range of −30 to + 50 ° C. of the melting point of the inner body of the outer skin. A method for producing a flexible tube for an endoscope, wherein the outer skin is tightly integrated with a mesh tube.
[0044]
(Additional Item 4) A flexible spiral tube formed by spirally winding a ribbon-shaped strip, a mesh tube covering the outside thereof, and a flexible endoscope composed of a sheath made of thermoplastic plastic. A flexible tube for an endoscope, wherein the melting point of the outer surface of the outer shell material is higher than that of the inner surface.
[0045]
(Additional Item 5) The flexible tube for an endoscope according to Additional Item 4, wherein the outer skin portion is formed of a tube.
(Additional Item 6) The flexible tube for an endoscope according to Additional Item 4, wherein the outer skin portion is formed by extruding a thermoplastic plastic onto the outer surface of the mesh tube.
[0046]
(Additional Item 7) The flexible tube for an endoscope according to Additional Item 4, wherein the outer skin portion surface is coated with a thermosetting or moisture-curing coating.
(Additional Item 8) The flexible tube for an endoscope according to Additional Item 4, wherein the surface of the outer skin portion is crosslinked by post-treatment to have thermosetting properties.
[0047]
(Supplementary Item 9) After covering the outer peripheral surface of the tube with the outer shell portion made of a spiral tube and a mesh tube, the outer shell portion is heated at a temperature of −30 to + 50 ° C. from the melting point of the inner surface material of the outer tube portion. A method for manufacturing a flexible tube for an endoscope, wherein the flexible tube is integrated.
[0048]
(Supplementary Note 10) After providing a skin portion on the outer surface of the component member composed of the spiral tube and the mesh tube, the outer surface is covered with a tube having a high melting point, and then heated at a temperature of -30 to + 50 ° C from the melting point of the material of the skin portion. And then removing the coated tube to integrate the outer skin portion and the reticulated tube, thereby producing a flexible tube for an endoscope.
[0049]
(Additional Item 11) The method for manufacturing an endoscope flexible tube according to Additional Item 10, wherein the covering tube is made of a high melting point material such as FEP, PFA, PTFE, or Si.
(Additional Item 12) The flexible tube for an endoscope according to Additional Items 4 and 5, wherein tubes having different hardnesses are joined to the outer tube.
(Additional Item 13) The flexible tube for an endoscope according to Additional Items 4 and 6, wherein the outer skin portion is formed by coating thermoplastic resin having different hardness on the outer surface of the mesh tube by extrusion.
[0050]
【The invention's effect】
According to the present invention, with a simple structure and a simple manufacturing method, the adhesion between the outer cover and the flexible tube material can be increased, uniform flexibility can be obtained, and the insertability into a body cavity and durability can be improved.
[Brief description of the drawings]
FIG. 1 is a side view showing a cross section of a main part of a flexible tube for an endoscope according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view showing a configuration of a main part of a flexible tube.
FIG. 3 is a longitudinal sectional view of a main part showing a modification of the flexible tube material of the first embodiment.
FIG. 4 is a longitudinal sectional view showing a configuration of a main part of a flexible tube for an endoscope according to a second embodiment of the present invention.
FIG. 5 is a longitudinal sectional view showing a configuration of a main part of a flexible tube for an endoscope according to a third embodiment of the present invention.
FIG. 6 is a longitudinal sectional view showing a configuration of a main part of a flexible tube for an endoscope according to a fourth embodiment of the present invention.
[Explanation of symbols]
2 helical tube, 3 reticular tube, 4 flexible tube material, 5 outer skin, 6, 11b, 21b high melting point layer, 31 coated tube (high melting point layer).

Claims

And spirally strips formed by winding spirally tube, the outer periphery of the endoscope insertion portion thermoplastic plastic outer skin is coated on the outer peripheral surface of the tubular structure comprising a mesh tube covering the outer periphery The flexible tube for an endoscope, wherein a high melting point layer having a higher melting point than the melting point inside the main body of the outer cover is provided on the outer surface of the outer cover.

A helical tube formed by spirally winding a belt made of a thermoplastic plastic outer skin having a high melting point layer having a melting point higher than the melting point inside the outer shell body on the outer surface of the outer shell body, and an outer periphery thereof After covering the outer peripheral surface of a flexible tube material consisting of a braided tube covering the outer cover, the outer cover is tightly integrated with the braided tube by heating at a heating temperature not lower than the softening point temperature inside the main body of the outer cover. A method for producing a flexible tube for an endoscope, comprising a step.

3. The flexible tube for an endoscope according to claim 2, wherein a heating temperature equal to or higher than a softening point temperature inside the main body of the outer skin is within a temperature range of 0 to + 50 ° C. with respect to a melting point. Method.