JP3772085B2

JP3772085B2 - Endoscope device

Info

Publication number: JP3772085B2
Application number: JP2000337968A
Authority: JP
Inventors: 康太石引
Original assignee: Olympus Corp
Current assignee: Olympus Corp
Priority date: 2000-11-06
Filing date: 2000-11-06
Publication date: 2006-05-10
Anticipated expiration: 2020-11-06
Also published as: JP2002143084A

Description

【０００１】
【発明の属する技術分野】
本発明は、管腔内に挿入される挿入部の先端側に湾曲部が配設された内視鏡装置に関する。
【０００２】
【従来の技術】
一般に、内視鏡の挿入部の先端側に配設された湾曲部に２つの湾曲部を直列に接続させた構成の内視鏡装置が知られている。例えば、実公平１−２２６４１号公報には図１７（Ａ）に示すように内視鏡の挿入部に配設された細長い可撓管部ａの先端側に４方向に湾曲可能な節輪構造を備えた第１湾曲部ｂが配設され、この第１湾曲部ｂの後端部に第１湾曲部ｂと略同じ節輪構造を備えた第２湾曲部ｃを連接させた構成の湾曲管装置が示されている。
【０００３】
また、図１７（Ａ）に示す２つの湾曲部ｂ、ｃを直列に接続させた構成の内視鏡の挿入部を例えば大腸ｄの直腸ｅとＳ状結腸ｆとの間の境界の屈曲部ｇなどを通過させる場合には第１湾曲部ｂの湾曲操作によってこの第１湾曲部ｂの部分を屈曲部ｇを通過させたのち、可撓管部ａを押込むことにより、第２湾曲部ｃおよび可撓管部ａの部分を続いて通過させる操作が行われている。
【０００４】
【発明が解決しようとする課題】
上記従来構成の構成の湾曲管装置を備えた内視鏡の挿入部を大腸ｄに挿入する場合には図１７（Ａ）に示す状態から、可撓管部ａを押し込むと、このときの押圧力が可撓管部ａと第２湾曲部ｃとの中継部に集中して図１７（Ｂ）に示すように、腸壁を押し、腸を過伸展させてしまうおそれがある。
【０００５】
また、図１７（Ｂ）に示す状態から更に可撓管部ａを押し込むと、図１７（Ｃ）に示すように可撓管部ａが撓んでしまい、挿入が困難となる。そのため、この場合には湾曲を戻す協調動作を行わないと、内視鏡の視野が腸壁の方向を向き、視野が確保できない問題がある。
【０００６】
さらに、実公平１−２２６４１号公報の湾曲管装置の構成では、大腸ｄへの挿入の際に、挿入部を把持する手の押し引きや、ねじり操作と、アングル操作とを協調させる必要があるので、Ｓ状結腸ｆ等の複雑な屈曲部を通過させる作業は難しく、比較的長い時間がかかる問題がある。
【０００７】
本発明は上記事情に着目してなされたもので、その目的は、Ｓ状結腸等の複雑な屈曲部を通過させる作業を容易に行うことができる内視鏡装置を提供することにある。
【０００８】
【課題を解決するための手段】
本発明は、管腔内に挿入される挿入部が細長い軟性の可撓管部と、前記挿入部の先端部に配設された先端構成部と、この先端構成部と前記可撓管部の先端部との間に介設された湾曲部とから形成される内視鏡装置において、
前記湾曲部に先端側に配置された第１の湾曲部と、この第１の湾曲部の基端側に連接され、前記第１の湾曲部よりも軸方向の曲げに対する硬さが硬くなる状態に設定された第２の湾曲部とを設け、
前記第２の湾曲部の後端位置を前記挿入部の先端部から略１５ｃｍ以上の長さに配置したことを特徴とする内視鏡装置である。
そして、本発明では、湾曲部を湾曲させた際に第１の湾曲部が第２の湾曲部に比べて湾曲し易く、第２の湾曲部は湾曲し難い状態で保持される。このとき、湾曲部を湾曲させた状態において、外力による曲げが第２の湾曲部に加えられると、第２の湾曲部を湾曲させることができる。これにより、大腸挿入時の屈曲部の通過の際に、第１の湾曲部を湾曲させた状態で腸壁に押し当てても第２の湾曲部が湾曲することにより、腸壁に力がかからないようにしたものである。そして、先端部が次の屈曲に近接する際に湾曲不能な硬質部である湾曲部の後端と可撓管との接続部が手前の屈曲に近接しないようにして、先端部が次の屈曲に近接するまで上記の作用を持続するようにしたものである。
【０００９】
【発明の実施の形態】
以下、本発明の第１の実施の形態を図１乃至図８を参照して説明する。図１は本実施の形態の内視鏡装置１の全体の概略構成を示すものである。この内視鏡装置１は撮像手段を備えた内視鏡２と、この内視鏡２に着脱自在に接続されて内視鏡２内に設けられたライトガイドに照明光を供給する光源装置３と、内視鏡２と信号ケーブル４を介して接続されて内視鏡２の撮像手段を制御すると共に撮像手段から得られた信号を処理するビデオプロセッサ５と、このビデオプロセッサ５から出力される被写体像に対応する映像を表示するモニタ６とから主に構成されている。
【００１０】
また、内視鏡２には可撓性を有する細長の挿入部７と、この挿入部７の基端側に接続された操作部８と、この操作部８の側部から延出した可撓性を有する連結コード９と、この連結コード９の端部に設けられたコネクタ部１０とが設けられている。そして、コネクタ部１０は光源装置３と着脱自在に接続されるようになっている。さらに、コネクタ部１０の側部には電気コネクタ部１１が設けられている。この電気コネクタ部１１にはビデオプロセッサ５と接続された信号ケーブル４が着脱自在に接続可能になっている。なお、電気コネクタ部１１には内視鏡２の内部と外部とを連通する図示しない通気部が設けられている。
【００１１】
挿入部７と操作部８との接続部にはこの接続部の急激な曲がりを防止する弾性部材を有する挿入部側折れ止め部材１２が設けられている。さらに、操作部８と連結コード９との接続部には同様の操作部側折れ止め部材１３、連結コード９とコネクタ部１０との接続部には同様のコネクタ部側折れ止め部材１４がそれぞれ設けられている。
【００１２】
また、挿入部７は可撓性を有する柔軟な可撓管部１５と、この可撓管部１５の先端側に設けられた操作部８の操作により湾曲可能な湾曲部１６と、先端に設けられ図示しない観察光学系、照明光学系などが配設された先端部１７とから構成されている。
【００１３】
先端部１７には送気操作、送水操作によって図示しない観察光学系の外表面の光学部材に向けて洗滌液体や気体を噴出するための送気送水ノズル１８と、挿入部７に配設された処置具を挿通したり体腔内の液体を吸引するための図示しない処置具チャンネルの先端側の開口である吸引口１９が設けられている。また、観察対象物に向けて開口した液体を噴出するための送液口２０とが設けられている。
【００１４】
コネクタ部１０の端面には光源装置３に内蔵された図示しない気体供給源と着脱自在に接続される気体供給口金２１と、ライトガイド接続部Ｌとが突設されている。さらに、コネクタ部１０の外周面には液体供給源である送水タンク２２と着脱自在に接続される送水タンク加圧口金２３及び液体供給口金２４とが設けられているとともに、先端部１７の吸引口１９より吸引を行うための図示しない吸引源と接続される吸引口金２５と、送液口２０より送水を行うための図示しない送水手段と接続される注入口金２６と、高周波処置等を行った際に内視鏡２に高周波漏れ電流が発生した場合に漏れ電流を高周波処置装置に帰還させるためのアース端子口金２７とが設けられている。
【００１５】
また、操作部８には送気操作、送水操作をそれぞれ操作する送気送水操作ボタン２８と、吸引操作を操作するための吸引操作ボタン２９と、湾曲部１６の湾曲操作を行うための湾曲操作ノブ３０と、ビデオプロセッサ５を遠隔操作する複数のリモートスイッチ３１と、処置具チャンネルに連通した開口である処置具挿入口３２とが設けられている。
【００１６】
なお、内視鏡２の電気コネクタ部１１にはこの電気コネクタ部１１を液密にシールするための防水キャップ３３が着脱自在に接続可能である。
【００１７】
また、本発明の要部である、湾曲部１６について説明する。図２に示すように内視鏡２の挿入部７の先端部１７にはステンレス（ＳＵＳ３０３）等の金属材料で形成された先端部本体３４が配置されている。この先端部本体３４の先端部及び外周部は樹脂等の絶縁材料からなる絶縁カバー部材３５で覆われている。
【００１８】
さらに、湾曲部１６には挿入部７の軸方向に沿って略リング状の複数の湾曲駒３７を並設させた管状の湾曲管３６が配設されている。この湾曲管３６を構成している複数の湾曲駒３７はリベット３８によって互いに回動自在に連結されている。
【００１９】
また、湾曲部１６の湾曲管３６を構成する複数の湾曲駒３７の最先端に位置する先端側湾曲駒３７ａは先端部本体３４の基端部に固定ねじ等により連結固定されている。さらに、湾曲管３６の基端部に位置する基端側湾曲駒３７ｂは可撓管部１５の先端部に設けられた先端側口金４３に固定ねじ等により連結固定されている。
【００２０】
また、湾曲管３６の外周面は細い金属素線を編んで筒状に形成された管状の網状管４１によってこの湾曲管３６全体が被嵌されている。ここで、網状管４１の先端と基端は先端側湾曲駒３７ａと基端側湾曲駒３７ｂにそれぞれ、半田、ロー付け、接着等の手段により固定されている。
【００２１】
さらに、網状管４１の外周には、フッ素ゴム等の弾性部材からなる弾性外皮部材４２が被覆されている。この弾性外皮部材４２の先端側は先端部本体３４の基端部に被覆され、基端側は先端側口金４３に被覆されている。そして、この弾性外皮部材４２における先端側の先端部本体３４の被覆部分および基端側の先端側口金４３の被覆部分は外周に巻回した図示しない固定用糸によって緊縛され、先端部本体３４、先端側口金４３にそれぞれ固定されている。さらに、固定用糸の外周側を覆う様に接着剤４５が塗布されてこれらが強固に固定され、これらの境界部分は水蜜的に封止されている。
【００２２】
また、各湾曲駒３７には内方向に半田やロー付けで固定されたワイヤガイド４９が設けられている。これらのワイヤガイド４９には操作部８から延出された牽引ワイヤ５０が挿通されている。この牽引ワイヤ５０の先端部は先端側湾曲駒３７ａに半田やロー付け等により固定されている。
【００２３】
さらに、可撓管部１５には牽引ワイヤ５０が挿通された密巻きコイル等からなる可撓性を有するガイドパイプ４４がワイヤガイド４９に相対して配設されている。このガイドパイプ４４の先端部は先端側口金４３に半田やロー付け等により固定されている。
【００２４】
また、本実施の形態の湾曲管３６には先端側に配設された第１の湾曲部３９と、この第１の湾曲部３９の基端側に連接され、第１の湾曲部３９よりも軸方向の曲げに対する硬さが硬くなる状態に設定された第２の湾曲部４０とが設けられている。なお、図２中で、Ｂ１は第１の湾曲部３９の範囲、Ｂ２は第２の湾曲部４０の範囲である。ここで、挿入部７の先端部１７の先端面と第１の湾曲部３９の後端位置との間の長さＹは例えば９０〜１２０ｍｍ程度の長さに設定されている。そして、第１の湾曲部３９の基端側の湾曲駒３７と、第２の湾曲部４０の最先端の湾曲駒３７との間はリベット３８により回動自在に連結されている。
【００２５】
また、各湾曲駒３７の隣合う湾曲駒３７が回動した際に互いに当接する当接部の間隔ｔは第１の湾曲部３９を構成する大部分の湾曲駒３７間の当接部の間隔ｔ１と、第２の湾曲部４０の湾曲駒３７間の当接部の間隔ｔ２との関係がｔ１＞ｔ２になるように設定されている。
【００２６】
さらに、図３に示すように第２の湾曲部４０を構成する部分の網状管４１の外周には、シリコン系接着剤等の弾性接着剤や、充填剤を塗布したり、ポリウレタン等の弾性を有する樹脂チューブ等を熱融着することによって、網状管４１を形成する金属素線の網目の中に、これらの弾性体を浸透させて形成された弾性膜部４６が形成されている。
【００２７】
また、弾性外皮部材４２には先端側に厚さが例えば０．５ｍｍの薄肉部４７が形成されている。そして、この弾性外皮部材４２の薄肉部４７の部分が第１の湾曲部３９に配設されている。
【００２８】
さらに、弾性外皮部材４２の基端側には第２の湾曲部４０に配設される厚さが例えば１ｍｍの厚肉部４８が形成されている。なお、薄肉部４７の部分と厚肉部４８との境界にはテーパ状に滑らかに肉厚が変化する肉厚変化部４８ａが形成されている。そして、厚肉部４８は網状管４１の弾性膜部４６が形成された部分と、弾性膜部４６が形成されていない部分との境界から５〜１５ｍｍ程度（Ｚ１）、基端側に配置されている。
【００２９】
また、網状管４１の弾性膜部４６の外周面には二硫化モリブデン等の減摩剤が塗布されている。これにより、弾性膜部４６の外面と弾性外皮部材４２の内面との間が滑るようになっている。
【００３０】
また、弾性外皮部材４２の長さ（自然長）は組付け位置に対して例えば５〜１５ｍｍ程度、長く形成されており、組付けられた状態では自然長に対して圧縮されるか、弛んだ状態となっている。この際、厚肉部４８は肉厚が厚いため、ほとんど弛まず、薄肉部４７の部分が弛むこととなる。
【００３１】
さらに、挿入部７の先端部１７の先端面と第２の湾曲部４０の後端位置との間の長さＸは略１５ｃｍ以上に形成されている。例えば１８〜２１ｃｍ程度に設定されている。これにより、第２の湾曲部４０の後端位置は挿入部７の先端部から略１５ｃｍ以上の長さに配置されている。
【００３２】
なお、図４は一般的な人体の大腸の構造を示すものである。ここで、Ｈ１は直腸、Ｈ２はＳ状結腸、Ｈ３は下行結腸、Ｈ４は横行結腸、Ｈ５は上行結腸である。さらに、Ｈ６はＲｓ屈曲部（直腸Ｈ１とＳ状結腸Ｈ２との境界部）、Ｈ７はＳＤ屈曲部（Ｓ状結腸Ｈ２と下行結腸Ｈ３との境界部）、Ｈ８は脾湾曲部（下行結腸Ｈ３と横行結腸Ｈ４との境界部）、Ｈ９は肝湾曲部（横行結腸Ｈ４と上行結腸Ｈ５との境界部）、Ｈ１０は脾湾曲部Ｈ８と肝湾曲部Ｈ９との間の横行結腸Ｈ４の略中央に位置する横行結腸中央屈曲部である。
【００３３】
また、文献「臨床消化器内科１９９９Ｖｏｌ．１４Ｎｏ．１」日本メディカルセンター発行の「一人法の基本的手技」田村智著の「Ｉ．大腸の走行」には大腸の最深部である上行結腸Ｈ５の長さＬ１は１５ｃｍ〜２０ｃｍであることが示されている。
【００３４】
さらに、文献「大腸内視鏡挿入法ビギナーからベテランまで」工藤著医学書院発行には大腸挿入時に腸を過度に伸展させない場合の内視鏡の挿入長、すなわち肛門からの長さＬとして、以下のデータが示されている。
【００３５】
Ｒｓ屈曲部Ｈ６までの長さＬ２は１５ｃｍ、ＳＤ屈曲部Ｈ７までの長さは３０ｃｍである。これより、Ｒｓ屈曲部Ｈ６から次の屈曲部であるＳＤ屈曲部Ｈ７までの長さＬ３は略１５ｃｍである。
【００３６】
また、脾湾曲部Ｈ８までの長さは４０ｃｍ、肝湾曲部Ｈ９までの長さは６０ｃｍ。これより、脾湾曲部Ｈ８と肝湾曲部Ｈ９との間の横行結腸Ｈ４の略中央に位置する横行結腸中央屈曲部Ｈ１０は脾湾曲側、肝湾曲側の何れかに偏っていた場合、中央屈曲部Ｈ１０と脾湾曲部Ｈ８との間の距離Ｌ４及び中央屈曲部Ｈ１０と肝湾曲部Ｈ９との距離Ｌ５は１０ｃｍ以上となる。
【００３７】
これらを考慮して、本発明における挿入部７の先端部１７の先端面と第２の湾曲部４０の後端位置との間の長さＸは以下の理由により１５ｃｍ以上に設定されている。
【００３８】
１．挿入部７を上行結腸Ｈ５へ挿入する作業中に、挿入部７の先端部１７の先端が上行結腸Ｈ５の深部に到達するまで、可撓管部１５が肝湾曲部Ｈ９に到達しないようにする。
【００３９】
２．挿入部７を直腸Ｈ１に挿入している作業中に、可撓管部１５が直腸Ｈ１に入らないようにする。
【００４０】
３．挿入部７をＳ状結腸Ｈ２に挿入している作業中に、可撓管部１５がＲｓ屈曲部Ｈ６に到達しないようにする。
【００４１】
４．挿入部７を横行結腸中央屈曲部Ｈ１０へ挿入する作業中に可撓管部１５が脾湾曲部Ｈ８に到達しないようにする。なお、ここで横行結腸中央屈曲部Ｈ１０が肝湾曲部Ｈ９側に偏っている場合には、Ｌ４が１０ｃｍ以上になる場合もあるため、１５ｃｍ程度とする。
【００４２】
５．挿入部７を肝湾曲部Ｈ９へ挿入する際に可撓管部１５が横行結腸中央湾曲部Ｈ１０に到達しないようにする。
【００４３】
以上の理由により、挿入部７の先端部１７の先端面と第２の湾曲部４０の後端位置との間の長さＸは略１５ｃｍ以上に設定されている。なお、望ましくはＸは１８ｃｍ〜２１ｃｍ程度に設定する。大腸の形態には個人差があるが、この場合には大部分の症例において、上記の関係が成り立つことになる。
【００４４】
また、湾曲部１６は術者が湾曲操作ノブ３０を操作することで、牽引ワイヤ５０が牽引操作され、湾曲管３６に内蔵された図示しない処置具挿通用チャンネル、送気送水管路、撮像素子に接続されたケーブル等の内蔵物の抵抗や、湾曲管３６に被嵌している網状管４１、弾性外皮部材４２の抵抗に抗して、複数の湾曲駒３７が回動して湾曲部１６が湾曲する構成となっている。ここで、湾曲部１６の基端側の第２の湾曲部４０は、網状管４１の弾性膜部４６、弾性外皮部材４２の厚肉部４８の抵抗により、第１の湾曲部３９よりも、曲がり難くなっている。なお、第１の湾曲部３９は上記に加えて、薄肉部４７が弛んでいることで、第２の湾曲部４０よりも曲がり易い。
【００４５】
また、湾曲部１６の湾曲操作時には湾曲により、弛んだ薄肉部４７が伸びた後、厚肉部４８に張力がかかり、厚肉部４８が伸び始めても、弾性膜部４６と弾性外皮部材４２との滑りが良いため、ある範囲までは弾性膜部４６と厚肉部４８との間が滑り、弾性膜部４６に力を与えないので、更に第２の湾曲部４０は曲がり難い状態で保持される。以上のようにして、第２の湾曲部４０は曲げに対する硬さが、第１の湾曲部３９よりも硬くなるように形成されている。
【００４６】
また、図５（Ａ）〜（Ｄ）は操作部８の湾曲操作ノブ３０の操作により、湾曲部１６を湾曲動作させた際の湾曲部１６の湾曲形状の設定状態を示すものである。本実施の形態では湾曲操作の際に図５（Ａ）〜（Ｄ）に示す形状となるように、各湾曲駒３７の当接部の間隔（ｔ１、ｔ２）、網状管４１の弾性膜部４６の材質、厚さ、弾性外皮部材４２の材質、厚さ、及び牽引ワイヤ５０の牽引量等の各要素を適宜調整して設定されている。
【００４７】
まず、湾曲部１６の湾曲動作の初期は湾曲部１６の基端側の第２の湾曲部４０は、第１の湾曲部３９よりも曲がり難いため、湾曲動作を行うと先端側の第１の湾曲部３９のみが先に湾曲し、図５（Ａ）に示す状態となる。
【００４８】
更に湾曲操作ノブ３０を回転操作して湾曲をかけると、第２の湾曲部４０の先端側も曲がり始め、図５（Ｂ）に示す状態となる。このとき、挿入部７の先端部１７の先端面の向きは挿入部７の中心線Ｏの方向に対する回転角度θ１が略９０°回転させた状態になっている。
【００４９】
また、図５（Ｂ）の状態から更に湾曲をかけ、挿入部７の先端部１７の先端面の向きが略１８０゜の方向を向く状態に湾曲させると図５（Ｃ）の状態となる。さらに、牽引ワイヤ５０を最大に牽引すると図５（Ｄ）の状態となる。
【００５０】
この図５（Ｄ）の状態では第１の湾曲部３９は、先端側を除くほとんどの隣合う湾曲駒３７間が当接した状態となる。このとき、第２の湾曲部４０は隣合う湾曲駒３７間が当接しないように各湾曲駒３７の当接部の間隔ｔ２と曲がり難さが設定されている。
【００５１】
次に、上記構成の本実施の形態の内視鏡装置１の作用について説明する。ここでは、図６（Ａ）〜（Ｆ）、図７（Ａ）〜（Ｇ）を参照して内視鏡２の挿入部７を大腸へ挿入する作業について説明する。
【００５２】
まず、肛門から挿入された挿入部７は、直腸Ｈ１に挿入される。この際、内視鏡２の挿入部７の先端が直腸Ｈ１の深部に到達するまで、可撓管部１５は直腸Ｈ１にほとんど挿入されない。そのため、挿入途中で、湾曲操作ノブ３０の湾曲操作により湾曲部１６を湾曲させて直腸Ｈ１のほぼ全長の形状をコントロールすることができる。そして、図６（Ａ）に示すように、直腸Ｈ１からＳ状結腸Ｈ２への移行部であるＲｓ屈曲部Ｈ６に達する。
【００５３】
続いて、図６（Ａ）の状態で、湾曲操作ノブ３０の湾曲操作により湾曲部１６を湾曲させて、図６（Ｂ）に示すように挿入部７の先端部１７、第１の湾曲部３９をＳ状結腸Ｈ２に導入する。
【００５４】
その後、湾曲部１６の基端部若しくは可撓管部１５を把持して可撓管部１５、湾曲部１６を挿入部７の押込み方向に押圧操作する。このとき、図６（Ｃ）に示すように湾曲部１６がＲｓ屈曲部Ｈ６の外側の腸壁に押し当てられることで第１の湾曲部３９、第２の湾曲部４０が曲がりながら、先端部１７が前進する。この作業中、第２の湾曲部４０は腸壁との接触によって容易に曲がるため、腸壁に力がかからず、図６（Ｃ）中に点線で示すように腸壁を伸展させることがない。また、可撓管部１５が撓んでしまうこともない。
【００５５】
図６（Ｃ）の状態から、更に湾曲部１６を押し込み方向に押圧操作すると、図６（Ｄ）に示すように挿入部７の先端部１７がＳ状結腸Ｈ２から下行結腸Ｈ３への移行部であるＳＤ屈曲部Ｈ７に到達する。ここで、湾曲操作ノブ３０の湾曲操作により湾曲部１６を湾曲させて、図６（Ｅ）に示すように先端部１７および第１の湾曲部３９を下行結腸Ｈ３に導入する。この際、湾曲部１６と可撓管部１５との接続部は直腸Ｈ１からＳ状結腸Ｈ２への移行部であるＲｓ屈曲部Ｈ６に近接していないので、この状態まで、腸壁に力がかかることがなく、腸壁の伸展や可撓管部１５の撓みを防止できる。
【００５６】
この状態で、湾曲を戻して湾曲部１６を略直線状に戻すか、湾曲操作ノブ３０が自由に回動可能な状態にして、可撓管部１５、湾曲部１６を引くと、図６（Ｆ）に示すように湾曲部１６が直線化される。これにより、直腸Ｈ１からＳ状結腸Ｈ２までの部分は湾曲部１６に沿ってほぼ、直線化される。
【００５７】
続いて、この状態で可撓管部１５を把持して押し進めれば、挿入部７は容易に下行結腸Ｈ３を前進していく。そして、図７（Ａ）に示すように挿入部７の先端部１７が下行結腸Ｈ３から横行結腸Ｈ４への移行部である脾湾曲部Ｈ８に到達する。
【００５８】
さらに、図７（Ａ）の状態で、湾曲操作ノブ３０の湾曲操作により湾曲部１６を湾曲させて、図７（Ｂ）に示すように挿入部７の先端部１７、第１の湾曲部３９を横行結腸Ｈ４に導入する。続いて、可撓管部１５を把持して押すと、図７（Ｃ）に示すように湾曲部１６が脾湾曲部Ｈ８の外側の腸壁に押し当てられることで第１の湾曲部３９及び第２の湾曲部４０が曲がりながら、前進する。この際、第２の湾曲部４０が容易に曲がるので、図７（Ｄ）に示すように腸壁に力がかからず、図７（Ｄ）中に点線で示すように腸壁を伸展させることがない。また、可撓管部１５が撓んでしまうこともない。
【００５９】
そして、可撓管部１５をさらに押していくと、図７（Ｅ）に示すように横行結腸Ｈ４の中央屈曲部Ｈ１０に到達する。ここで、湾曲操作ノブ３０の湾曲操作により湾曲部１６を湾曲させて、図７（Ｆ）に示すように横行結腸Ｈ４の中央屈曲部Ｈ１０より深部に挿入部７の先端部１７、第１の湾曲部３９を導入する。この際、湾曲部１６と可撓管部１５との間の接続部は下行結腸Ｈ３から横行結腸Ｈ４への移行部である脾湾曲部Ｈ８に近接していないので、この状態まで、腸壁に力がかかることがなく、腸壁の伸展や可撓管部１５の撓みを防止できる。
【００６０】
そして、可撓管部１５を押して、更に挿入部７を押し進める。この際、可撓管部１５を押してもよいが、湾曲部１６の湾曲を戻して直線化するか、湾曲操作ノブ３０が自由に回動可能な状態にして可撓管部１５を引くことにより、図７（Ｇ）に示すように湾曲部１６が直線化される。これにより、横行結腸Ｈ４は湾曲部１６に沿ってほぼ、直線化された状態で挿入部７の挿入が可能となる。
【００６１】
なお、次の屈曲部である肝湾曲部Ｈ９の通過については図示しないが同様の作用で、内視鏡２の挿入部７が挿入される。
【００６２】
そして、大腸の最深部で最もコントロールし難く、可撓管部１５を押した力が最も伝わり難くなる、上行結腸Ｈ５への挿入時には、挿入部７の先端部１７が上行結腸Ｈ５の深部に到達するまで、湾曲部１６と、可撓管部１５との接続部が肝湾曲部Ｈ９に到達しないため、腸に力を与えず、腸の過度な伸展や、可撓管部１５の撓みを防止できる。
【００６３】
また、図８は湾曲操作ノブ３０による湾曲操作で湾曲部１６を単一方向へ湾曲させ、湾曲操作ノブ３０を固定した状態を示すものである。ここで、湾曲操作ノブ３０の操作により、湾曲部１６に角度θａの湾曲をかけると挿入部７の先端部１７はａの状態で保持される。
【００６４】
この状態において、第２の湾曲部４０の各湾曲駒３７は互いに当接していないため、湾曲部１６に図８中の矢印Ｆの外力が与えられると、第２の湾曲部４０の各湾曲駒３７が回動して更に湾曲し、挿入部７の先端部１７をｂ、ｃの状態に曲げることができる。ここで、湾曲操作ノブ３０の回動位置を動かさない場合には、牽引ワイヤ５０の牽引量は変わらないことから、ｂ、ｃの状態に曲げた場合の挿入部７の先端部１７の向き（湾曲角度）θｂとθｃはθａとほぼ変わらず、第２の湾曲部４０が外力により曲がった角度とほぼ同一の量だけ第１の湾曲部３９の湾曲駒３７が湾曲が戻る方向に回動して、第１の湾曲部３９の湾曲は解除され、第１の湾曲部３９は軸方向に伸びる。これにより、挿入部７の先端部１７は視野方向、すなわち進行したい方向にほぼ、直線的に移動する。
【００６５】
これにより、図６（Ｃ）および図７（Ｄ）に示す状態の際に腸壁に湾曲部１６を押し付けて、湾曲部１６を変形させることにより、特別な湾曲操作をすることなく、視野を確保しながら自動的に視野方向に先端部１７を前進させることができる。
【００６６】
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、本実施の形態の内視鏡装置１では内視鏡２の湾曲部１６に先端側の第１の湾曲部３９と、この第１の湾曲部３９の基端側に連接され、第１の湾曲部３９よりも軸方向の曲げに対する硬さが硬くなる状態に設定された第２の湾曲部４０とを設け、第２の湾曲部４０の後端位置を挿入部７の先端部から略１５ｃｍ以上の長さに配置したので、湾曲部１６の全長が長いにも関わらず、湾曲操作ノブ３０の操作による湾曲動作時には、第１の湾曲部３９のみを主に湾曲させ、第２の湾曲部４０はほとんど湾曲しない状態で保持させることができる。そのため、湾曲部１６の通過の際に可撓管部１５の押し操作をして、湾曲部１６を腸壁に押し付けた際に、容易に第２の湾曲部４０が曲がるため、腸壁が過度に伸展することを防止することができる。このとき、可撓管部１５が撓まないので、先端部１７の進行方向に力が確実に伝わり、屈曲部の通過が容易になる。
【００６７】
さらに、図５（Ｄ）に示すように湾曲操作ノブ３０の操作による湾曲動作で湾曲部１６を最大湾曲状態に湾曲操作した際にも、第２の湾曲部４０の各湾曲駒３７は当接していないため、どの様な湾曲動作状態においても、第２の湾曲部４０に外力が加わった場合には、図５（Ｄ）の点線で示すように、更に第２の湾曲部４０を湾曲させることができる。また、湾曲部１６が長いにもかかわらず、湾曲操作ノブ３０の操作では湾曲部４０はほとんど湾曲しないので、湾曲形状がコンパクトで、狭い腸管の中でも操作性が良い。
【００６８】
また、湾曲部１６と可撓管部１５との間の接続部のように曲がらない硬質部分が大腸内のＲｓ屈曲部Ｈ６のような屈曲部に近接する前に先端部１７、第１の湾曲部３９を次の屈曲部であるＳＤ屈曲部Ｈ７に導入することができるので、この状態で湾曲部１６の形状を変えることで、腸管を直線化し、挿入部７の挿入を容易にすることができる。
【００６９】
さらに、本実施の形態では大腸内の屈曲部の通過の際に内視鏡２の視野を確保しながら、挿入できるため、挿入部７の挿入が容易となる。以上により、本実施の形態では大腸内の屈曲部の通過時における腸の過伸展やステッキ現象が防止でき、大腸への挿入部７の挿入を容易に行うことができる。
【００７０】
また、本実施の形態では、湾曲部１６の網状管４１と弾性外皮部材４２と湾曲管３６とを組み合わせた状態において、湾曲部１６の曲げに対する硬さが次の表１に示す関係となるようにそれぞれ形成されている。
【００７１】
【表１】

【００７２】
そして、図３に示すように網状管４１の弾性膜部４６のある部分と無い部分の境界部分よりも基端側に弾性外皮部材４２の厚肉部４８を位置させて、弾性膜部４６の部分と薄肉部４７とが組み合わされた上記表１の３の組み合わせ部分のように、曲げに対する硬さが中間の硬さの部分を設けている。
【００７３】
この場合には湾曲部１６の途中部分に硬さが急激に変化する部分がないので、湾曲部１６の湾曲操作時の湾曲形状がスムーズな形状となる。さらに、図６（Ｃ）や、図７（Ｄ）に示す状態の際に腸壁に湾曲部１６を押し付けても、第１の湾曲部３９と第２の湾曲部４０との接続部に、急激に屈曲する部分が生じず、曲げに対する硬さが急激に変化する部分がないので、可撓管部１５の押し操作をした際に、第１の湾曲部３９と第２の湾曲部４０との途中部分に力が集中して、腸壁に力を与えることがない。このため、腸壁が伸展せず、可撓管部１５が撓まない。さらに、湾曲部１６の湾曲時に湾曲部１６の外表面に急激な段差が生じない効果もある。
【００７４】
また、第１の湾曲部３９と第２の湾曲部４０との間の接続部の部分を、曲げに対する硬さが比較的軟らかい構成としたので、湾曲操作を行った際に、第１の湾曲部３９の基端部が曲がり易く、コンパクトな形状となる。
【００７５】
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、湾曲部１６の通過時における腸の過伸展やステッキ現象が防止でき、大腸への挿入が容易な内視鏡２を提供できる。第２の湾曲部４０を曲がり難くするための抵抗として、網状管４１と弾性外皮部材４２とを用いているので、実公平１−２２６４１号公報の構成のような不具合がない。
【００７６】
さらに、本実施の形態の内視鏡装置１では湾曲部１６の第１の湾曲部３９の形状がコンパクトで従来の一般的な内視鏡と同様であり、大腸への挿入において湾曲操作によって先端部１７および第１の湾曲部３９を大腸の腸壁にひっかけて、湾曲部１６の湾曲動作によって腸管をたたみ、短縮させる動作が容易に行える。また、先端部１７および第１の湾曲部３９を大腸のひだにかけて、湾曲操作によりひだをかきわける動作がし易くなり、ひだの裏側の観察性が良い。
【００７７】
また、大腸への内視鏡２の挿入方法には大別して２つの方法がある。第１の方法は可撓管部１５を把持し、押し込む動作を主体として、挿入部７の先端を深部に押し進める挿入方法である。また、第２の方法は可撓管部１５を押し込む動作と共に、湾曲操作によって先端部１７を大腸の腸壁にひっかけて、湾曲部１６の湾曲動作によって腸管をたたみ、短縮させる動作を主体として、挿入部７の先端部１７を深部へ導く挿入方法である。
【００７８】
そして、上記の構成の本実施の形態の内視鏡装置１によれば、第１の方法で発生し易い腸の過伸展や、ステッキ現象を防止することができると共に、第２の方法においても操作性を損なうことがない。
【００７９】
また、本実施の形態では第２の湾曲部４０の曲げに対する硬さは、可撓管部１５との接続部近傍の可撓管部１５の曲げに対する硬さよりも小さくなるように、湾曲部１６、先端部１７内部に配置された内蔵物の曲げに対する硬さや、内蔵物の湾曲部１６、先端部１７に対する充填率、湾曲部１６、可撓管部１５の各要素を構成している。
【００８０】
そして、図５（Ｂ）に示すように湾曲操作ノブ３０の操作により湾曲部１６を９０゜以上湾曲させた状態においても、可撓管部１５と、湾曲部１６の硬さの関係が上記と同様に構成されている。
【００８１】
なお、湾曲部１６の湾曲角度が９０゜程度に屈曲された状態は、腸の屈曲部を越える際に、次の管腔に挿入部７の先端部１７を入れるために通常、必要な最低の角度である。そして、内視鏡２の挿入部７を大腸内に挿入する作業中、内視鏡２の湾曲部１６を腸の屈曲部を通過させる際に、湾曲部１６の湾曲角度が９０゜以上の角度がついた状態で可撓管部１５を押す場合には、内視鏡２に力を加える方向と、挿入部７の先端部１７が向いた方向、すなわち挿入部７の先端部１７を進める方向とが異なることとなる。９０°を越えると逆方向になる。
【００８２】
このため、この状態で可撓管部１５を押込み操作した場合には従来構成の内視鏡では図１７（Ｂ）に示すように、湾曲部ｃが腸壁を押す方向にしか力が加わらないので、押した方向に腸壁が過度に伸展したり、可撓管部１５が撓んでしまい、所謂ステッキ現象が起こってしまう。
【００８３】
なお、本実施の形態においては図５（Ｄ）における湾曲操作ノブ３０の操作による最大湾曲状態においても、可撓管部１５と湾曲部１６の硬さの関係も上記と同様に構成されている。そのため、内視鏡２の挿入部７を大腸内に挿入する作業中に、大腸内の屈曲部においてどの様な大きさの湾曲をかけた状態でも、可撓管部１５に力を加えると、湾曲部１６が腸壁と滑らない状態でも、可撓管部１５が撓み始める前に湾曲部１６の第２の湾曲部４０が変形し、確実に先端部１７を前進させることができる。
【００８４】
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、本実施の形態では内視鏡２の挿入部７を大腸内に挿入する作業中に、大腸内の屈曲部において可撓管部１５が撓んで、先端部１７に力が伝わらなくなることがないので、内視鏡２の挿入部７を大腸内の屈曲部を通過させる際の作業性が良い。
【００８５】
なお、可撓管部１５の湾曲部１６との接続部近傍部分を軟性部５１とし、この基端側に軟性部５１よりも長手方向の曲げに対する硬さを硬くした図示しない硬性部を設けても良い。
【００８６】
また、図９（Ａ），（Ｂ）および図１０（Ａ）〜（Ｄ）は第１の実施の形態（図１乃至図８参照）の内視鏡装置１の第１の変形例を示すものである。本変形例は内視鏡２の湾曲部１６の構成を次の通り変更したものである。
【００８７】
図９（Ａ）は湾曲部１６の単一方向への湾曲操作時に牽引ワイヤ５０の動作ストロークにより湾曲させることが可能な最大湾曲状態を示すものである。そして、本変形例ではこの湾曲部１６の最大湾曲状態時に、第２の湾曲部４０の先端部の軸線Ｓ１と可撓管部１５の中心線Ｓ２との間の角度α１を略４５゜以下とし、第１の湾曲部３９の先端部の軸線Ｓ３と第２の湾曲部４０の先端部の軸線Ｓ１との間の角度α２を略１８０゜以上の角度を有するように、湾曲部１６の湾曲駒３７、網状管４１、弾性膜部４６及び牽引ワイヤ５０のストロークを設定したものである。ここで、本変形例ではα１を２０゜、α２を１８０゜にそれぞれ設定し、可撓管部１５の中心線Ｓ２に沿う略直線状の自然状態に対しては合計２００゜の湾曲がかかるように形成されている。
【００８８】
なお、内視鏡２による大腸検査時には直腸Ｈ１において、直腸内反転視と呼ばれている肛門Ｈ１１付近の観察が行われる場合がある。これは、内視鏡２の挿入部７を肛門Ｈ１１から直腸Ｈ１に挿入した際に、挿入方向に向いている挿入部７の先端部１７を湾曲操作ノブ３０の湾曲操作によって湾曲部１６を１８０゜以上湾曲させることで、図９（Ａ）に示すように内視鏡２の視野方向を挿入方向に対してほぼ正反対に向けて観察を行うものである。
【００８９】
ここで、湾曲部１６の最大湾曲状態時に、第２の湾曲部４０の先端部の軸線Ｓ１と可撓管部１５の中心線Ｓ２との間の角度α１を４５゜以上とした場合には図９（Ｂ）に示すように、観察したい肛門付近を正面側から観察することができない。そこで、本変形例のように湾曲部１６の最大湾曲状態時に、第２の湾曲部４０の先端部の軸線Ｓ１と可撓管部１５の中心線Ｓ２との間の角度α１を４５゜以下に設定したことにより、図９（Ａ）に示すように肛門Ｈ１１付近を正面側から観察することができる。
【００９０】
次に、図９（Ａ）に示す湾曲部１６の最大湾曲状態から、この湾曲方向と直交する方向へ更に湾曲をかけた際の湾曲動作について図１０（Ａ）〜（Ｄ）を参照して説明する。図１０（Ａ），（Ｂ）は図９（Ａ）と同様の湾曲部１６の最大湾曲状態を示すものである。この状態では第１の湾曲部３９は、ほとんどの隣り合う湾曲駒３７の当接部間が当接している。このとき、第２の湾曲部４０は、ほとんどの隣り合う湾曲駒３７の当接部間は当接していない。
【００９１】
この状態から、湾曲部１６に図１０（Ｂ）に示すように湾曲がかけられている方向と直交する方向である矢印Ｒ、矢印Ｌの方向に更に湾曲をかけると、第１の湾曲部３９は湾曲駒３７が当接して固定状態にあるため、ほとんど、形状が変化しない。一方、第２の湾曲部４０では各湾曲駒３７が当接していないため、新たに湾曲をかけた方向に湾曲駒３７が回動し、図１０（Ｃ）、図１０（Ｄ）に示す湾曲形状にそれぞれ変形される。
【００９２】
そこで、本変形例では、肛門Ｈ１１付近を観察する際、図１０（Ａ），（Ｂ）の状態から、図１０（Ｃ）、図１０（Ｄ）の状態に変形させても先端部１７と観察対象物との距離を大きく変化させることがなく、図１０（Ａ），（Ｂ）の状態で観察していた対象物の周辺を観察できる。さらに、本変形例では第１の湾曲部３９の部分の湾曲角度がほとんど増加しないので、湾曲部１６の内蔵物にダメージを与えない効果もある。
【００９３】
なお、図９（Ａ）に示す湾曲部１６の最大湾曲状態において、第２の湾曲部４０の先端部の軸線Ｓ１と可撓管部１５の中心線Ｓ２との間の角度α１を４５゜以上とした場合でも９０゜以下に設定するのが望ましい。
【００９４】
なお、図５（Ｂ）に示すように、湾曲操作ノブ３０の湾曲操作により、湾曲部１６を自然状態（挿入部７の中心線Ｏの方向）に対して略９０゜の回転角度θ１に湾曲させる際の湾曲操作時に、第１の湾曲部３９が９０゜まで湾曲する前に、第２の湾曲部４０が湾曲し始める構成にしている。
【００９５】
ここで、大腸の屈曲部、例えば図１１（Ａ），（Ｂ）に示すＲｓ屈曲部Ｈ６や、図１２（Ａ），（Ｂ）に示す脾湾曲部Ｈ８などは通常、９０゜以下の鋭角である。そのため、内視鏡２の挿入部７を大腸へ挿入する操作時には、Ｒｓ屈曲部Ｈ６や、脾湾曲部Ｈ８などを通過させる際に、挿入部７の先端部１７の視野を屈曲部の先の管腔方向に向けるため、湾曲部１６を少なくとも、９０゜以上の角度に湾曲させる必要がある。このとき、湾曲部１６は第２の湾曲部４０が湾曲することにより、図１１（Ｂ）、図１２（Ｂ）に示すように、腸壁を第２の湾曲部４０が押すことで屈曲部が鈍角になり、湾曲部１６の通過が容易になる。
【００９６】
さらに、図６（Ｃ）、図７（Ｄ）に示す状態で、腸壁に湾曲部１６を押し付ける際に、既に第２の湾曲部４０が第１の湾曲部３９と同方向に曲がっている為、図１３に示すように第２の湾曲部４０が第１の湾曲部３９の湾曲方向と逆の方向に曲がってしまうことがない。
【００９７】
また、図１４は第１の実施の形態（図１乃至図８参照）の内視鏡装置１の第２の変形例を示すものである。本変形例は内視鏡２の湾曲部１６の構成を次の通り変更したものである。
【００９８】
すなわち、本変形例では図１４に示すように、湾曲操作ノブ３０の操作による最大湾曲角度（挿入部７の中心線Ｏの方向に対する回転角度θ２）を１８０゜に設定し、この範囲までは第２の湾曲部４０が曲がり始めないように設定したものである。
【００９９】
この場合は、従来、広く用いられている一般的な第２の湾曲部４０のない内視鏡と、全く、湾曲形状が変わらないので、内視鏡の湾曲操作時の操作感覚が変わらず、従来の操作方法に慣れている術者に対して違和感がない。
【０１００】
また、図５（Ｃ）に示すように湾曲操作ノブ３０の操作により、湾曲部１６を自然状態に対して略１８０゜湾曲させた状態において、挿入部７の先端部１７は湾曲部１６と可撓管部１５との接続部よりも、先端側に位置する形状に設定してもよい。
【０１０１】
この場合には挿入部７の挿入口である、肛門Ｈ１１に近いＳ状結腸Ｈ２の通過及び、Ｓ状結腸Ｈ２と下行結腸Ｈ３との移行部であるＳＤ屈曲部Ｈ７の通過において各屈曲部を通過させるために、通常、湾曲部１６は１８０゜以上は曲げる必要がない。このため、湾曲部１６を曲げた場合でも、湾曲部１６の基端部分を把持することができる。
【０１０２】
そして、これらの部位の挿入において、第２の湾曲部４０を把持し、曲げることにより第２の湾曲部４０及び第１の湾曲部３９の湾曲形状を任意に変えることができる。例えば、湾曲操作ノブ３０にて湾曲をかけ、湾曲操作ノブ３０を保持した状態で、把持した手で第２の湾曲部４０を曲げれば、前述した図８に示す作用により、第１の湾曲部３９は角度が鈍角になり、第２の湾曲部４０を鈍角にすれば、第１の湾曲部３９は鋭角に湾曲形状が変化する。特に、肛門Ｈ１１から直腸Ｈ１までは上記操作が行えるし、腸壁をたたみ、腸管を短縮化しながら挿入すれば、Ｓ状結腸Ｈ２から下行結腸Ｈ３への移行部まで、上記操作が行える。
【０１０３】
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、湾曲部１６の形状を挿入部７を把持した手で、挿入部７の押し引き操作と連動して湾曲形状を調整できるので、操作性が良く、挿入性が良くなる。また、前述した直腸内反転視の際も観察視野の調整がし易くなる効果がある。
【０１０４】
また、図１５および図１６は本発明の第２の実施の形態を示すものである。本実施の形態は第１の実施の形態（図１乃至図８参照）の内視鏡装置１の内視鏡２における湾曲部１６の構成を次の通り変更したものである。
【０１０５】
すなわち、本実施の形態の湾曲部１６では図１５に示すように、第１の実施の形態とは逆に第１の湾曲部３９の外周面の弾性外皮部材４２の薄肉部４７の部分の後端部側に弾性外皮部材４２の厚肉部４８を延設させたものである。ここで、弾性外皮部材４２の厚肉部４８は網状管４１の弾性膜部４６のある部分と無い部分との境界部分よりも適宜の長さ先端側まで延出されている。この弾性外皮部材４２の厚肉部４８の延出部分の長さＺ２は例えば５ｍｍ〜１５ｍｍ程度に設定されている。そして、この弾性外皮部材４２の厚肉部４８の延出部分の長さＺ２の部分に弾性膜部４６がない部分と厚肉部４８とが組み合わされた、曲げに対する硬さが中間の硬さの部分（表１の２に相当する）が形成されている。
【０１０６】
そして、本実施の形態では湾曲部１６の第１の湾曲部３９と第２の湾曲部４０との接続部に曲げに対する硬さが比較的硬い長さＺ２の中間の硬さの部分を設けたので、湾曲操作を行った際には、第１の湾曲部３９の基端部が曲がり難くなり、第２の湾曲部４０の先端側が曲がり易く、図１６に示す湾曲形状となる。
【０１０７】
そのため、大腸の屈曲部において、湾曲操作により、湾曲部１６に湾曲をかけると腸の屈曲部の形状が第１の実施形態よりも、更に鈍角な形状となるので、可撓管部１５を押した際に、加えた力が挿入部７の先端部１７に伝わり易く、挿入部７の先端部１７が挿入方向に推進し易くなる。
【０１０８】
そこで、本実施の形態では大腸の屈曲部に内視鏡２の挿入部７を挿入する際に大腸の屈曲部に挿入部７の先端部１７を通過させる操作がさらに容易となり、挿入性が向上する効果がある。
【０１０９】
さらに、本発明は上記実施の形態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。
記
（付記項１）先端部と先端部の基端に接続された湾曲部と湾曲部の基端に接続された可撓管とからなる軟性の挿入部とを有する内視鏡装置において、
前記湾曲部の長さを先端から略１５ｃｍ以上に形成し、
前記湾曲部は先端側に設けられた第一湾曲部と、
第一湾曲部の基端側に連接した第一湾曲部よりも軸方向の曲げに対する硬さが硬く形成された第二湾曲部とを具備する内視鏡装置。
【０１１０】
（付記項２）前記第一湾曲部と第二湾曲部は複数の節輪部材を回動自在に連結した湾曲管部材を具備し、
湾曲管部材に第一湾曲部と第二湾曲部の軸方向の曲げに対する硬さを異ならせる抵抗部材を外嵌したことを特徴とする付記項１の内視鏡装置。
【０１１１】
（付記項３）前記湾曲部は湾曲管部材の外周を被嵌する被嵌部材と、
被嵌部材の外周を被覆する弾性外皮部材とからなり、
前記被嵌部材は湾曲部の軸方向の曲げに対する硬さの異なる先端側の軟質部と基端側の硬質部を有し、
弾性外皮部材は湾曲部の軸方向の曲げに対する硬さの異なる先端側の軟質部と基端側の硬質部を具備する付記項２の内視鏡装置。
【０１１２】
（付記項４）前記被嵌部材の硬質部と軟質部との硬度変化位置と、弾性外皮部材の硬質部と軟質部との硬度変化位置とを湾曲部の軸方向の異なる位置に設けたことを特徴とする付記項３の内視鏡装置。
【０１１３】
（付記項５）弾性外皮部材の硬度変化位置を被嵌部材の硬度変化位置よりも先端側に設けた付記項４の内視鏡装置。
【０１１４】
（付記項６）弾性外皮部材の硬度変化位置を被嵌部材の硬度変化位置よりも基端側に設けた付記項４の内視鏡装置。
【０１１５】
（付記項７）湾曲操作手段による操作ワイヤの牽引操作によって、湾曲部を少なくとも略９０°以上湾曲させた状態において、第二湾曲部の軸方向の曲げに対する硬さを第二湾曲部に接続された可撓管の軸方向の曲げに対する硬さよりも小さく形成した付記項１の内視鏡装置。
【０１１６】
（付記項８）湾曲操作手段による湾曲操作によって湾曲させることが可能な湾曲部の最大湾曲状態において、
第二湾曲部の軸方向の曲げに対する硬さを第二湾曲部に接続された可撓管の軸方向の曲げに対する硬さよりも小さく形成した付記項１の内視鏡装置。
【０１１７】
（付記項９）前記湾曲部が、略１８０°曲げられたときに、
先端部の位置が湾曲部と可撓管との接続部よりも軸方向先端側に位置するよう湾曲部を形成した付記項１の内視鏡装置。
【０１１８】
（付記項１０）先端部と先端部の基端に接続された湾曲部と湾曲部の基端に接続された可撓管とからなる軟性の挿入部を有する内視鏡装置において、
前記湾曲部は先端側に設けられた第一湾曲部と、
第一湾曲部の基端側に連接した第一湾曲部よりも軸方向の曲げに対する硬さが硬く形成された第二湾曲部とを具備し、
第一湾曲部と第二湾曲部は複数の節輪部材を回動自在に連結した湾曲管部材にて形成し、
第一湾曲部の節輪部材の少なくとも１つに端部が固定された操作ワイヤを有し、
湾曲操作手段による操作ワイヤの牽引操作によって湾曲部を略９０°以上湾曲させた状態において、
第二湾曲部の軸方向の曲げに対する硬さを第二湾曲部に接続された可撓管の軸方向の曲げに対する硬さよりも小さく形成したことを特徴とする内視鏡装置。
【０１１９】
（付記項１１）湾曲操作手段による操作ワイヤの牽引操作によって湾曲させることが可能な湾曲部の最大湾曲状態において第二湾曲部の軸方向の曲げに対する硬さを第二湾曲部に接続された可撓管の軸方向の曲げに対する硬さよりも小さく形成したことを特徴とする付記項１０の内視鏡装置。
【０１２０】
（付記項１〜１１の従来技術）実公平１−２２６４１号公報。
【０１２１】
（付記項１が解決しようとする課題）実公平１−２２６４１号公報では、第二湾曲部の長さについては考慮されていないため、第二湾曲部と、可撓管との接続部である中継管が体腔内屈曲部に近接すると、図１７（Ａ）に示す状態から、可撓管を押し込むと、力が中継管に集中して図１７（Ｂ）に示すように、腸壁を押し、腸を過伸展させてしまう。更に可撓管を押し込むと、図１７（Ｃ）に示すように可撓管がたわんでしまい、挿入が困難となり、湾曲を戻す協調動作を行わないと、視野が腸壁の方向を向き、視野が確保できない。
【０１２２】
（付記項９が解決しようとする課題）実公平１−２２６４１号公報の構成では、大腸への挿入の際に、挿入部を把持する手の押し引きやねじり操作と、アングル操作を協調させる必要があり、Ｓ状結腸等の複雑な屈曲を通過するのは困難であった。
【０１２３】
（付記項１０が解決しようとする課題）実公平１−２２６４１号公報では、第二湾曲部にそれ自身の伸縮量が少ないステーコイルが内蔵されているため、第二湾曲部に外力が与えられた際に第二湾曲部が自由に曲がることができず、湾曲部を湾曲操作手段により湾曲をかけた際には、湾曲によりステーコイルが圧縮ないし伸張させられたことによるステーコイルの復元力が発生することにより、第二湾曲部は外力によっては更に曲がり難くなってしまい、曲げに対する硬さの変化が大きい変化点が第二湾曲部にできたり、第二湾曲部の曲げに対する硬さが、接続された近傍の可撓管の曲げに対する硬さよりも硬くなってしまう。このため、挿入において、湾曲をかけた状態で可撓管を押し込むと、図１５（Ｃ）に示すように可撓管が撓んで挿入困難となる。
【０１２４】
（付記項１の作用）湾曲操作手段の操作により、湾曲部を湾曲させた際に第一湾曲部が湾曲し易く、第二湾曲部は湾曲し難いので第二湾曲部はほとんど湾曲しない。このため、湾曲した状態において、外力による曲げが加えられると、第二湾曲部は湾曲することができる。これにより、大腸挿入時の屈曲部の通過の際に、湾曲部を湾曲した状態で腸壁に押し当てても第二湾曲部が湾曲することにより、腸壁に力がかからない。更に硬質部である湾曲部と可撓管との接続部が屈曲部に近接した際には、先端部は次の屈曲に導入される。
【０１２５】
（付記項９の作用）肛門から直腸における、腸の屈曲部の通過の為に湾曲部を湾曲させた状態でも第二湾曲部の一部が把持出来る。これを把持して、把持した手で第二湾曲部を曲げれば、第一湾曲部の湾曲形状がこれに連動して変化するので、湾曲操作手段の操作をすることなく第一湾曲部の湾曲形状を調整できる。
【０１２６】
（付記項１０の作用）腸の屈曲部の通過の際に、湾曲部を湾曲させた状態で腸壁に押し当てても、可撓管が撓み始める前に第二湾曲部が確実に曲がるので、腸壁に力がかからない。
【０１２７】
【発明の効果】
本発明によれば、湾曲部に先端側に配置された第１の湾曲部と、この第１の湾曲部の基端側に連接され、第１の湾曲部よりも軸方向の曲げに対する硬さが硬くなる状態に設定された第２の湾曲部とを設け、第２の湾曲部の後端位置を挿入部の先端部から略１５ｃｍ以上の長さに配置したので、Ｓ状結腸等の複雑な屈曲部を通過させる作業を容易に行うことができる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態の内視鏡装置の全体の概略構成図。
【図２】第１の実施の形態の内視鏡装置における内視鏡の湾曲部の内部構成を示す縦断面図。
【図３】第１の実施の形態の内視鏡装置における内視鏡の湾曲部の第１の湾曲部と第２の湾曲部との接続部分を示す要部の縦断面図。
【図４】一般的な人体の大腸の構造を示す概略構成図。
【図５】第１の実施の形態の内視鏡装置における内視鏡の湾曲部の動作を説明するための説明図。
【図６】第１の実施の形態の内視鏡装置における内視鏡の挿入部を大腸の直腸、Ｓ状結腸、下行結腸内に挿入する操作を説明するための説明図。
【図７】第１の実施の形態の内視鏡装置における内視鏡の挿入部を大腸の下行結腸から横行結腸内に挿入する操作を説明するための説明図。
【図８】第１の実施の形態の内視鏡装置における内視鏡の湾曲部の第１の湾曲部と第２の湾曲部の動作を説明するための説明図。
【図９】第１の実施の形態の内視鏡装置における内視鏡の湾曲部の第１の変形例の作用を説明するための説明図。
【図１０】第１の変形例の内視鏡の湾曲部の作用を説明するための説明図。
【図１１】内視鏡の挿入部を大腸の直腸からＳ状結腸へ挿入する作用を説明するための説明図。
【図１２】内視鏡の挿入部を大腸の下行結腸から横行結腸へ挿入する作用を説明するための説明図。
【図１３】第２の湾曲部が第１の湾曲部の湾曲方向と逆の方向に曲がった状態を説明するための説明図。
【図１４】第１の実施の形態の内視鏡装置における内視鏡の湾曲部の第２の変形例を示す正面図。
【図１５】本発明の第２の実施の形態の内視鏡装置における内視鏡の湾曲部を示す要部の縦断面図。
【図１６】第２の実施の形態の内視鏡装置における内視鏡の湾曲部の作用を説明するための説明図。
【図１７】従来の内視鏡装置における内視鏡の湾曲部の作用を説明するための説明図。
【符号の説明】
２内視鏡
７挿入部
１５可撓管部
１６湾曲部
１７先端部（先端構成部）
３９第１の湾曲部
４０第２の湾曲部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope apparatus in which a bending portion is disposed on a distal end side of an insertion portion that is inserted into a lumen.
[0002]
[Prior art]
In general, an endoscope apparatus having a configuration in which two bending portions are connected in series to a bending portion disposed on a distal end side of an insertion portion of an endoscope is known. For example, Japanese Utility Model Publication No. 1-22641 discloses a nodal ring structure that can be bent in four directions on the distal end side of an elongated flexible tube portion a disposed in an insertion portion of an endoscope as shown in FIG. A curved portion having a configuration in which a second curved portion c having the same node ring structure as that of the first curved portion b is connected to the rear end portion of the first curved portion b. A tube device is shown.
[0003]
In addition, an insertion portion of an endoscope having a configuration in which two curved portions b and c shown in FIG. 17A are connected in series is a bent portion at the boundary between the rectum e of the large intestine d and the sigmoid colon f, for example. When passing g or the like, the second bending portion is formed by pushing the flexible tube portion a after passing the portion of the first bending portion b through the bending portion g by the bending operation of the first bending portion b. The operation of passing the portion of c and the flexible tube portion a in succession is performed.
[0004]
[Problems to be solved by the invention]
When the insertion portion of the endoscope having the bending tube device having the above-described conventional configuration is inserted into the large intestine d, when the flexible tube portion a is pushed in from the state shown in FIG. As shown in FIG. 17B, the pressure concentrates on the relay portion between the flexible tube portion a and the second bending portion c, and the intestinal wall may be pushed and the intestine may be excessively stretched.
[0005]
If the flexible tube portion a is further pushed in from the state shown in FIG. 17B, the flexible tube portion a is bent as shown in FIG. 17C, making insertion difficult. Therefore, in this case, unless a cooperative operation for returning the curvature is performed, there is a problem that the visual field of the endoscope faces the intestinal wall and the visual field cannot be secured.
[0006]
Furthermore, in the configuration of the bending tube device disclosed in Japanese Utility Model Publication No. 1-22641, when inserting into the large intestine d, it is necessary to coordinate the push / pull of the hand holding the insertion portion, the twisting operation, and the angle operation. Therefore, it is difficult to pass a complicated bent portion such as the sigmoid colon f, and there is a problem that it takes a relatively long time.
[0007]
The present invention has been made paying attention to the above circumstances, and an object of the present invention is to provide an endoscope apparatus capable of easily performing a work of passing a complicated bent portion such as a sigmoid colon.
[0008]
[Means for Solving the Problems]
The present invention relates to a flexible flexible tube portion having an elongated insertion portion to be inserted into a lumen, a distal end configuration portion disposed at a distal end portion of the insertion portion, and the distal end configuration portion and the flexible tube portion. In an endoscope apparatus formed from a curved portion interposed between a distal end portion,
A state in which the first bending portion disposed on the distal end side of the bending portion and the proximal end side of the first bending portion are connected, and the hardness with respect to the bending in the axial direction is harder than that of the first bending portion. And a second bending portion set to
In the endoscope apparatus, the rear end position of the second bending portion is disposed at a length of about 15 cm or more from the distal end portion of the insertion portion.
In the present invention, when the bending portion is bent, the first bending portion is easier to bend than the second bending portion, and the second bending portion is held in a state where it is difficult to bend. At this time, when the bending by the external force is applied to the second bending portion in a state where the bending portion is bent, the second bending portion can be bent. As a result, when the bent portion is passed through the large intestine, even if it is pressed against the intestinal wall in a state where the first bent portion is bent, the second bent portion is bent so that no force is applied to the intestinal wall. It is what I did. And when the tip is close to the next bend The connecting portion between the rear end of the bending portion, which is a hard portion that cannot be bent, and the flexible tube is not brought close to the previous bend, and the above-mentioned until the tip portion comes close to the next bend. It is intended to sustain the action of.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an overall schematic configuration of an endoscope apparatus 1 according to the present embodiment. The endoscope apparatus 1 includes an endoscope 2 having an imaging unit, and a light source apparatus 3 that is detachably connected to the endoscope 2 and supplies illumination light to a light guide provided in the endoscope 2. A video processor 5 connected to the endoscope 2 via the signal cable 4 to control the imaging means of the endoscope 2 and process a signal obtained from the imaging means, and output from the video processor 5 It is mainly composed of a monitor 6 that displays an image corresponding to a subject image.
[0010]
Further, the endoscope 2 has a flexible elongated insertion portion 7, an operation portion 8 connected to the proximal end side of the insertion portion 7, and a flexible portion extending from the side portion of the operation portion 8. A connecting cord 9 having the characteristics and a connector portion 10 provided at an end portion of the connecting cord 9 are provided. The connector unit 10 is detachably connected to the light source device 3. Furthermore, an electrical connector portion 11 is provided on the side portion of the connector portion 10. A signal cable 4 connected to the video processor 5 can be detachably connected to the electrical connector portion 11. The electrical connector portion 11 is provided with a ventilation portion (not shown) that communicates the inside and the outside of the endoscope 2.
[0011]
The connecting portion between the inserting portion 7 and the operating portion 8 is provided with an inserting portion side folding preventing member 12 having an elastic member for preventing a sudden bending of the connecting portion. Further, a similar operation part side folding member 13 is provided at the connection part between the operation part 8 and the connecting cord 9, and a similar connector part side folding member 14 is provided at the connection part between the connection cord 9 and the connector part 10. It has been.
[0012]
The insertion portion 7 includes a flexible flexible tube portion 15 having flexibility, a bending portion 16 that can be bent by operation of the operation portion 8 provided on the distal end side of the flexible tube portion 15, and a distal end. The distal end portion 17 is provided with an observation optical system, an illumination optical system, and the like (not shown).
[0013]
An air supply / water supply nozzle 18 for ejecting a cleaning liquid or gas toward the optical member on the outer surface of the observation optical system (not shown) by an air supply operation and a water supply operation and an insertion portion 7 are disposed at the distal end portion 17. A suction port 19 that is an opening on the distal end side of a treatment tool channel (not shown) for inserting the treatment tool or sucking the liquid in the body cavity is provided. In addition, a liquid supply port 20 for ejecting the liquid that is opened toward the observation object is provided.
[0014]
A gas supply base 21 detachably connected to a gas supply source (not shown) built in the light source device 3 and a light guide connection portion L project from the end face of the connector portion 10. Further, a water supply tank pressure cap 23 and a liquid supply cap 24 that are detachably connected to a water supply tank 22 that is a liquid supply source are provided on the outer peripheral surface of the connector portion 10, and a suction port of the tip end portion 17 is provided. When performing a high-frequency treatment, a suction base 25 connected to a suction source (not shown) for suctioning from 19, an injection base 26 connected to a water supply means (not shown) for feeding water from the liquid feeding port 20 Further, an earth terminal base 27 is provided for returning the leakage current to the high-frequency treatment device when a high-frequency leakage current is generated in the endoscope 2.
[0015]
The operation unit 8 includes an air / water supply operation button 28 for operating an air supply operation and a water supply operation, a suction operation button 29 for operating the suction operation, and a bending operation for performing the bending operation of the bending unit 16. A knob 30, a plurality of remote switches 31 for remotely operating the video processor 5, and a treatment instrument insertion port 32 which is an opening communicating with the treatment instrument channel are provided.
[0016]
A waterproof cap 33 for sealing the electrical connector part 11 in a liquid-tight manner can be detachably connected to the electrical connector part 11 of the endoscope 2.
[0017]
Moreover, the bending part 16 which is the principal part of this invention is demonstrated. As shown in FIG. 2, a distal end portion body 34 made of a metal material such as stainless steel (SUS303) is disposed at the distal end portion 17 of the insertion portion 7 of the endoscope 2. The distal end portion and the outer peripheral portion of the distal end portion main body 34 are covered with an insulating cover member 35 made of an insulating material such as resin.
[0018]
Further, the bending portion 16 is provided with a tubular bending tube 36 in which a plurality of substantially ring-shaped bending pieces 37 are arranged in parallel along the axial direction of the insertion portion 7. A plurality of bending pieces 37 constituting the bending tube 36 are connected to each other by rivets 38 so as to be rotatable.
[0019]
Further, the distal end side bending piece 37a located at the forefront of the plurality of bending pieces 37 constituting the bending tube 36 of the bending portion 16 is connected and fixed to the proximal end portion of the distal end portion main body 34 by a fixing screw or the like. Further, the proximal-side bending piece 37b located at the proximal end portion of the bending tube 36 is connected and fixed to a distal end side cap 43 provided at the distal end portion of the flexible tube portion 15 by a fixing screw or the like.
[0020]
The entire outer surface of the bending tube 36 is fitted by a tubular mesh tube 41 formed into a tubular shape by knitting a thin metal wire. Here, the distal end and the proximal end of the mesh tube 41 are fixed to the distal end-side bending piece 37a and the proximal-side bending piece 37b by means of soldering, brazing, adhesion, or the like.
[0021]
Further, the outer circumference of the mesh tube 41 is covered with an elastic skin member 42 made of an elastic member such as fluororubber. The distal end side of the elastic skin member 42 is covered with the proximal end portion of the distal end portion main body 34, and the proximal end side is covered with the distal end side base 43. The covering portion of the distal end side main body 34 and the covering portion of the distal end side base 43 in the elastic outer skin member 42 are bound by a fixing thread (not shown) wound around the outer periphery, Each is fixed to the distal end side cap 43. Further, an adhesive 45 is applied so as to cover the outer peripheral side of the fixing yarn, and these are firmly fixed, and the boundary portions are sealed in a hydrated manner.
[0022]
Each bending piece 37 is provided with a wire guide 49 fixed inward by soldering or brazing. A pulling wire 50 extending from the operation unit 8 is inserted through these wire guides 49. The tip of the puller wire 50 is fixed to the tip-side bending piece 37a by soldering or brazing.
[0023]
Further, a flexible guide pipe 44 made of a tightly wound coil or the like through which the pulling wire 50 is inserted is disposed in the flexible tube portion 15 so as to be opposed to the wire guide 49. The distal end portion of the guide pipe 44 is fixed to the distal end side base 43 by soldering or brazing.
[0024]
In addition, the bending tube 36 of the present embodiment is connected to the first bending portion 39 disposed on the distal end side and the proximal end side of the first bending portion 39, and is more than the first bending portion 39. A second bending portion 40 is provided which is set in a state where the hardness against bending in the axial direction is increased. In FIG. 2, B <b> 1 is a range of the first bending portion 39, and B <b> 2 is a range of the second bending portion 40. Here, the length Y between the distal end surface of the distal end portion 17 of the insertion portion 7 and the rear end position of the first bending portion 39 is set to a length of about 90 to 120 mm, for example. The bending piece 37 on the proximal end side of the first bending portion 39 and the most advanced bending piece 37 of the second bending portion 40 are connected to each other by a rivet 38 so as to be freely rotatable.
[0025]
Further, the interval t between the abutting portions that abut each other when the adjacent bending pieces 37 of each bending piece 37 are rotated is the interval between the abutting portions between most of the bending pieces 37 constituting the first bending portion 39. The relationship between t1 and the distance t2 of the contact portion between the bending pieces 37 of the second bending portion 40 is set so that t1> t2.
[0026]
Further, as shown in FIG. 3, an elastic adhesive such as a silicon-based adhesive or a filler is applied to the outer periphery of the portion of the mesh tube 41 constituting the second bending portion 40, and elasticity such as polyurethane is applied. By heat-sealing the resin tube or the like, the elastic film portion 46 formed by infiltrating these elastic bodies is formed in the mesh of the metal wire forming the mesh tube 41.
[0027]
The elastic skin member 42 is formed with a thin portion 47 having a thickness of, for example, 0.5 mm on the tip side. A portion of the thin portion 47 of the elastic skin member 42 is disposed on the first curved portion 39.
[0028]
Further, a thick wall portion 48 having a thickness of, for example, 1 mm is formed on the base end side of the elastic skin member 42. It should be noted that a thickness changing portion 48a in which the thickness smoothly changes in a tapered shape is formed at the boundary between the thin portion 47 and the thick portion 48. The thick portion 48 is disposed on the proximal end side about 5 to 15 mm (Z1) from the boundary between the portion of the mesh tube 41 where the elastic membrane portion 46 is formed and the portion where the elastic membrane portion 46 is not formed. ing.
[0029]
Further, a lubricant such as molybdenum disulfide is applied to the outer peripheral surface of the elastic film portion 46 of the mesh tube 41. Thereby, the space between the outer surface of the elastic film portion 46 and the inner surface of the elastic skin member 42 can be slid.
[0030]
Further, the length (natural length) of the elastic skin member 42 is formed to be long, for example, about 5 to 15 mm with respect to the assembly position, and in the assembled state, it is compressed or loosened with respect to the natural length. It is in a state. At this time, since the thick portion 48 is thick, the thin portion 47 is hardly loosened and the thin portion 47 is loosened.
[0031]
Further, the length X between the distal end surface of the distal end portion 17 of the insertion portion 7 and the rear end position of the second bending portion 40 is formed to be approximately 15 cm or more. For example, it is set to about 18 to 21 cm. Thereby, the rear end position of the second bending portion 40 is arranged at a length of about 15 cm or more from the distal end portion of the insertion portion 7.
[0032]
FIG. 4 shows the structure of a general human large intestine. Here, H1 is the rectum, H2 is the sigmoid colon, H3 is the descending colon, H4 is the transverse colon, and H5 is the ascending colon. Further, H6 is an Rs bend (a boundary between the rectum H1 and the sigmoid colon H2), H7 is an SD bend (a boundary between the sigmoid colon H2 and the descending colon H3), and H8 is a splenic curve (the descending colon H3). H9 is a liver curvature (boundary between the transverse colon H4 and the ascending colon H5), and H10 is an approximate center of the transverse colon H4 between the splenic curvature H8 and the liver curvature H9. Is the central flexion of the transverse colon.
[0033]
In addition, the literature “Clinical Gastrointestinal Internal Medicine 1999 Vol.14 No.1” “Basic Techniques for One Person Method” published by Japan Medical Center, “I. Running of the Large Intestine” written by Satoshi Tamura, shows the ascending colon H5, the deepest part of the large intestine. The length L1 is shown to be between 15 cm and 20 cm.
[0034]
In addition, the literature “Intestinal Endoscopy Insertion from Beginner to Veteran” written by Kudo Medical School published the length of insertion from the anus when the intestine does not extend excessively, that is, length L from the anus. Data is shown.
[0035]
The length L2 to the Rs bent portion H6 is 15 cm, and the length to the SD bent portion H7 is 30 cm. Accordingly, the length L3 from the Rs bent portion H6 to the SD bent portion H7 which is the next bent portion is approximately 15 cm.
[0036]
Moreover, the length to the splenic curved part H8 is 40 cm, and the length to the liver curved part H9 is 60 cm. As a result, when the transverse colon central bent portion H10 located at the approximate center of the transverse colon H4 between the splenic curved portion H8 and the liver curved portion H9 is biased to either the splenic curved side or the liver curved side, the central bent The distance L4 between the portion H10 and the splenic curved portion H8 and the distance L5 between the central bent portion H10 and the liver curved portion H9 are 10 cm or more.
[0037]
Considering these, the length X between the distal end surface of the distal end portion 17 of the insertion portion 7 and the rear end position of the second bending portion 40 in the present invention is set to 15 cm or more for the following reason.
[0038]
1. During the operation of inserting the insertion portion 7 into the ascending colon H5, the flexible tube portion 15 is prevented from reaching the liver bending portion H9 until the distal end of the distal end portion 17 of the insertion portion 7 reaches the deep portion of the ascending colon H5. .
[0039]
2. During the operation of inserting the insertion portion 7 into the rectum H1, the flexible tube portion 15 is prevented from entering the rectum H1.
[0040]
3. During the operation of inserting the insertion portion 7 into the sigmoid colon H2, the flexible tube portion 15 is prevented from reaching the Rs bent portion H6.
[0041]
4). The flexible tube portion 15 is prevented from reaching the splenic curved portion H8 during the operation of inserting the insertion portion 7 into the transverse colon central bent portion H10. Here, when the transverse colon central bent portion H10 is biased toward the hepatic curved portion H9, L4 may be 10 cm or more, so it is about 15 cm.
[0042]
5). When the insertion portion 7 is inserted into the liver bending portion H9, the flexible tube portion 15 is prevented from reaching the transverse colon central bending portion H10.
[0043]
For the above reasons, the length X between the distal end surface of the distal end portion 17 of the insertion portion 7 and the rear end position of the second bending portion 40 is set to approximately 15 cm or more. Desirably, X is set to about 18 cm to 21 cm. There are individual differences in the form of the large intestine, but in this case, the above relationship is established in most cases.
[0044]
The bending portion 16 is operated by the operator operating the bending operation knob 30 so that the pulling wire 50 is pulled, and a treatment instrument insertion channel (not shown), an air / water supply conduit, an image sensor, which are built in the bending tube 36, are provided. A plurality of bending pieces 37 are rotated against the resistance of a built-in object such as a cable connected to the cable, the resistance of a mesh tube 41 fitted to the bending tube 36, and the resistance of the elastic skin member 42, and the bending portion 16 is rotated. Is configured to bend. Here, the second bending portion 40 on the base end side of the bending portion 16 is more resistant than the first bending portion 39 due to the resistance of the elastic film portion 46 of the mesh tube 41 and the thick portion 48 of the elastic skin member 42. It is difficult to bend. In addition to the above, the first bending portion 39 is easier to bend than the second bending portion 40 because the thin portion 47 is slack.
[0045]
In addition, when the bending portion 16 is bent, the thinned portion 47 that is slackened due to the bending is stretched, and then the thick portion 48 is tensioned. Even if the thick portion 48 begins to stretch, the elastic film portion 46 and the elastic skin member 42 Since the sliding of the elastic film portion 46 and the thick-walled portion 48 slips to a certain extent and does not apply force to the elastic film portion 46, the second bending portion 40 is further held in a state where it is difficult to bend. The As described above, the second bending portion 40 is formed so as to be harder to bend than the first bending portion 39.
[0046]
5A to 5D show the setting state of the bending shape of the bending portion 16 when the bending portion 16 is bent by the operation of the bending operation knob 30 of the operation portion 8. In the present embodiment, the distance (t1, t2) between the contact portions of the bending pieces 37 and the elastic film portion of the mesh tube 41 so that the shapes shown in FIGS. Each element such as the material 46 and the thickness 46, the material and thickness of the elastic skin member 42, and the pulling amount of the pulling wire 50 is appropriately adjusted and set.
[0047]
First, since the second bending portion 40 on the proximal end side of the bending portion 16 is less likely to bend than the first bending portion 39 at the initial stage of the bending operation of the bending portion 16, when the bending operation is performed, the first bending portion 16 on the distal end side. Only the bending portion 39 is bent first, and the state shown in FIG.
[0048]
When the bending operation knob 30 is further rotated to bend, the distal end side of the second bending portion 40 begins to bend, and the state shown in FIG. 5B is obtained. At this time, the direction of the distal end surface of the distal end portion 17 of the insertion portion 7 is such that the rotation angle θ1 with respect to the direction of the center line O of the insertion portion 7 is rotated by approximately 90 °.
[0049]
Further, when the curve is further applied from the state of FIG. 5B and the distal end surface of the distal end portion 17 of the insertion portion 7 is bent in the direction of about 180 °, the state of FIG. 5C is obtained. Further, when the pulling wire 50 is pulled to the maximum, the state shown in FIG.
[0050]
In the state of FIG. 5D, the first bending portion 39 is in a state where most adjacent bending pieces 37 except for the distal end side are in contact with each other. At this time, in the second bending portion 40, the interval t2 between the contact portions of the bending pieces 37 and the difficulty of bending are set so that the adjacent bending pieces 37 do not contact each other.
[0051]
Next, the operation of the endoscope apparatus 1 of the present embodiment having the above configuration will be described. Here, an operation of inserting the insertion portion 7 of the endoscope 2 into the large intestine will be described with reference to FIGS. 6 (A) to (F) and FIGS. 7 (A) to (G).
[0052]
First, the insertion portion 7 inserted from the anus is inserted into the rectum H1. At this time, the flexible tube portion 15 is hardly inserted into the rectum H1 until the distal end of the insertion portion 7 of the endoscope 2 reaches the deep portion of the rectum H1. Therefore, during the insertion, the bending portion 16 can be bent by the bending operation of the bending operation knob 30 to control the shape of the almost full length of the rectum H1. Then, as shown in FIG. 6A, it reaches an Rs bent portion H6 that is a transition portion from the rectum H1 to the sigmoid colon H2.
[0053]
Subsequently, in the state of FIG. 6A, the bending portion 16 is bent by the bending operation of the bending operation knob 30, so that the distal end portion 17 of the insertion portion 7 and the first bending portion as shown in FIG. 6B. 39 is introduced into the sigmoid colon H2.
[0054]
Thereafter, the proximal end portion of the bending portion 16 or the flexible tube portion 15 is grasped, and the flexible tube portion 15 and the bending portion 16 are pressed in the pushing direction of the insertion portion 7. At this time, as shown in FIG. 6 (C), the bending portion 16 is pressed against the intestinal wall outside the Rs bending portion H6, so that the first bending portion 39 and the second bending portion 40 are bent while the distal end portion is bent. 17 moves forward. During this operation, the second bending portion 40 is easily bent by contact with the intestinal wall, so that no force is applied to the intestinal wall, and the intestinal wall can be extended as shown by a dotted line in FIG. Absent. Further, the flexible tube portion 15 is not bent.
[0055]
When the bending portion 16 is further pressed in the pushing direction from the state of FIG. 6C, the distal end portion 17 of the insertion portion 7 is a transition portion from the sigmoid colon H2 to the descending colon H3 as shown in FIG. 6D. The SD bent portion H7 is reached. Here, the bending portion 16 is bent by the bending operation of the bending operation knob 30, and the distal end portion 17 and the first bending portion 39 are introduced into the descending colon H3 as shown in FIG. 6 (E). At this time, since the connecting portion between the bending portion 16 and the flexible tube portion 15 is not close to the Rs bending portion H6 that is a transition portion from the rectum H1 to the sigmoid colon H2, force is applied to the intestinal wall until this state. This prevents the intestinal wall from extending and the flexible tube portion 15 from being bent.
[0056]
In this state, when the bending portion 16 is returned and the bending portion 16 is returned to a substantially linear shape or the bending operation knob 30 is freely rotatable and the flexible tube portion 15 and the bending portion 16 are pulled, FIG. As shown in F), the bending portion 16 is linearized. As a result, the portion from the rectum H1 to the sigmoid colon H2 is substantially linearized along the curved portion 16.
[0057]
Subsequently, if the flexible tube portion 15 is grasped and pushed in this state, the insertion portion 7 easily advances the descending colon H3. Then, as shown in FIG. 7A, the distal end portion 17 of the insertion portion 7 reaches a splenic curved portion H8 that is a transition portion from the descending colon H3 to the transverse colon H4.
[0058]
Further, in the state of FIG. 7A, the bending portion 16 is bent by the bending operation of the bending operation knob 30, and the distal end portion 17 of the insertion portion 7 and the first bending portion 39 as shown in FIG. 7B. Is introduced into the transverse colon H4. Subsequently, when the flexible tube portion 15 is gripped and pressed, the bending portion 16 is pressed against the intestinal wall outside the splenic bending portion H8 as shown in FIG. The second bending portion 40 moves forward while bending. At this time, since the second bending portion 40 is easily bent, no force is applied to the intestinal wall as shown in FIG. 7D, and the intestinal wall is extended as shown by a dotted line in FIG. 7D. There is nothing. Further, the flexible tube portion 15 is not bent.
[0059]
Then, when the flexible tube portion 15 is further pushed, it reaches the central bent portion H10 of the transverse colon H4 as shown in FIG. 7 (E). Here, the bending portion 16 is bent by the bending operation of the bending operation knob 30, and as shown in FIG. 7 (F), the distal end portion 17 of the insertion portion 7 and the first portion are deeper than the central bending portion H10 of the transverse colon H4. The bending portion 39 is introduced. At this time, the connecting portion between the bending portion 16 and the flexible tube portion 15 is not close to the splenic bending portion H8 which is a transition portion from the descending colon H3 to the transverse colon H4. No force is applied, and the extension of the intestinal wall and the bending of the flexible tube portion 15 can be prevented.
[0060]
And the flexible tube part 15 is pushed and the insertion part 7 is further pushed forward. At this time, the flexible tube portion 15 may be pushed. However, the bending portion 16 may be returned to be linearized or the bending operation knob 30 may be freely rotated to pull the flexible tube portion 15. As shown in FIG. 7G, the bending portion 16 is linearized. Accordingly, the insertion portion 7 can be inserted while the transverse colon H4 is substantially linearized along the curved portion 16.
[0061]
In addition, although passing through the liver bending part H9 which is the next bending part is not shown in figure, the insertion part 7 of the endoscope 2 is inserted by the same effect | action.
[0062]
The distal end portion 17 of the insertion portion 7 reaches the deep portion of the ascending colon H5 at the time of insertion into the ascending colon H5. Until this is done, the connecting portion between the bending portion 16 and the flexible tube portion 15 does not reach the liver bending portion H9, so that force is not applied to the intestine, and excessive intestinal extension or bending of the flexible tube portion 15 is prevented. it can.
[0063]
FIG. 8 shows a state where the bending operation knob 30 is bent in a single direction by the bending operation of the bending operation knob 30 and the bending operation knob 30 is fixed. Here, when the bending portion 16 is bent at an angle θa by the operation of the bending operation knob 30, the distal end portion 17 of the insertion portion 7 is held in the state of a.
[0064]
In this state, since the bending pieces 37 of the second bending portion 40 are not in contact with each other, when the external force indicated by the arrow F in FIG. 37 is rotated and further curved, and the distal end portion 17 of the insertion portion 7 can be bent into the states of b and c. Here, when the turning position of the bending operation knob 30 is not moved, the pulling amount of the pulling wire 50 does not change, so the direction of the distal end portion 17 of the insertion portion 7 when bent to the state of b and c ( (Bending angle) θb and θc are substantially the same as θa, and the bending piece 37 of the first bending portion 39 is rotated in the direction in which the bending is returned by the same amount as the angle at which the second bending portion 40 is bent by the external force. Thus, the bending of the first bending portion 39 is released, and the first bending portion 39 extends in the axial direction. Thereby, the front-end | tip part 17 of the insertion part 7 moves substantially linearly in the visual field direction, ie, the direction which wants to advance.
[0065]
Accordingly, the bending portion 16 is pressed against the intestinal wall in the state shown in FIGS. 6C and 7D, and the bending portion 16 is deformed, so that the visual field can be reduced without performing a special bending operation. The tip 17 can be automatically advanced in the visual field direction while ensuring.
[0066]
Therefore, the above configuration has the following effects. That is, in the endoscope apparatus 1 according to the present embodiment, the first bending portion 39 on the distal end side is connected to the bending portion 16 of the endoscope 2 and the proximal end side of the first bending portion 39 is connected to the first bending portion 39. The second bending portion 40 is set so as to be harder in bending in the axial direction than the bending portion 39, and the rear end position of the second bending portion 40 is substantially from the distal end portion of the insertion portion 7. Since the length of the bending portion 16 is long, only the first bending portion 39 is mainly bent during the bending operation by the operation of the bending operation knob 30 because the bending portion 16 is long. The part 40 can be held in a state of hardly bending. For this reason, when the flexible tube portion 15 is pushed when passing through the bending portion 16 and the bending portion 16 is pressed against the intestinal wall, the second bending portion 40 easily bends, so that the intestinal wall is excessive. Can be prevented from extending to the surface. At this time, since the flexible tube portion 15 does not bend, the force is reliably transmitted in the traveling direction of the tip portion 17 and the passage of the bent portion is facilitated.
[0067]
Further, as shown in FIG. 5D, each bending piece 37 of the second bending portion 40 also comes into contact when the bending portion 16 is bent to the maximum bending state by the bending operation by the operation of the bending operation knob 30. Therefore, in any bending operation state, when an external force is applied to the second bending portion 40, the second bending portion 40 is further bent as shown by the dotted line in FIG. be able to. Even though the bending portion 16 is long, the bending portion 40 hardly bends when the bending operation knob 30 is operated. Therefore, the bending shape is compact, and the operability is good even in a narrow intestine.
[0068]
Further, before the hard portion that does not bend like the connection portion between the bending portion 16 and the flexible tube portion 15 approaches the bent portion such as the Rs bent portion H6 in the large intestine, the distal end portion 17 and the first bent portion Since the portion 39 can be introduced into the SD bent portion H7, which is the next bent portion, changing the shape of the curved portion 16 in this state can straighten the intestinal tract and facilitate the insertion of the insertion portion 7. it can.
[0069]
Furthermore, in the present embodiment, the insertion portion 7 can be easily inserted because the insertion can be performed while ensuring the visual field of the endoscope 2 when passing through the bent portion in the large intestine. As described above, according to the present embodiment, it is possible to prevent intestinal overextension and a sticking phenomenon when passing through a bent portion in the large intestine, and the insertion portion 7 can be easily inserted into the large intestine.
[0070]
Further, in the present embodiment, the bending resistance of the bending portion 16 has the relationship shown in the following Table 1 in a state where the mesh tube 41, the elastic skin member 42, and the bending tube 36 of the bending portion 16 are combined. Are formed respectively.
[0071]
[Table 1]

[0072]
Then, as shown in FIG. 3, the thick portion 48 of the elastic skin member 42 is positioned closer to the base end side than the boundary portion between the portion where the elastic membrane portion 46 is present and the portion where the elastic membrane portion 46 is not present. Like the combination part of 3 of the said Table 1 with which the part and the thin part 47 were combined, the part with the hardness with respect to bending is provided in the middle.
[0073]
In this case, since there is no portion where the hardness changes suddenly in the middle portion of the bending portion 16, the bending shape during the bending operation of the bending portion 16 becomes a smooth shape. Furthermore, even if the bending portion 16 is pressed against the intestinal wall in the state shown in FIG. 6C or 7D, the connection portion between the first bending portion 39 and the second bending portion 40 is Since there is no portion that suddenly bends and there is no portion in which the hardness against bending suddenly changes, when the flexible tube portion 15 is pushed, the first bending portion 39 and the second bending portion 40 The force concentrates on the middle part of the stomach and does not give power to the intestinal wall. For this reason, the intestinal wall does not extend and the flexible tube portion 15 does not bend. Furthermore, there is also an effect that no sharp step is generated on the outer surface of the bending portion 16 when the bending portion 16 is bent.
[0074]
In addition, since the portion of the connecting portion between the first bending portion 39 and the second bending portion 40 is configured to have a relatively soft hardness against bending, the first bending is performed when the bending operation is performed. The base end portion of the portion 39 is easy to bend and has a compact shape.
[0075]
Therefore, the above configuration has the following effects. That is, it is possible to provide an endoscope 2 that can prevent intestinal overextension and a sticking phenomenon when passing through the bending portion 16 and can be easily inserted into the large intestine. Since the mesh tube 41 and the elastic skin member 42 are used as the resistance for making the second bending portion 40 difficult to bend, there is no problem as in the configuration of Japanese Utility Model Publication No. 1-22641.
[0076]
Furthermore, in the endoscope apparatus 1 of the present embodiment, the shape of the first bending portion 39 of the bending portion 16 is compact and is the same as that of a conventional general endoscope. By hooking the portion 17 and the first bending portion 39 on the intestinal wall of the large intestine, the bending operation of the bending portion 16 can be used to easily collapse and shorten the intestinal tract. In addition, the distal end portion 17 and the first bending portion 39 are placed on the folds of the large intestine, and the operation of breaking the folds by the bending operation is facilitated, and the observability on the back side of the folds is good.
[0077]
There are two main methods of inserting the endoscope 2 into the large intestine. The first method is an insertion method in which the distal end of the insertion portion 7 is pushed deeper with the flexible tube portion 15 held and pushed in as a subject. In addition, the second method mainly has an operation of pushing the flexible tube portion 15, hooking the distal end portion 17 to the intestinal wall of the large intestine by a bending operation, and folding and shortening the intestinal tract by the bending operation of the bending portion 16. This is an insertion method in which the distal end portion 17 of the insertion portion 7 is guided to the deep portion.
[0078]
According to the endoscope apparatus 1 of the present embodiment having the above-described configuration, it is possible to prevent intestinal hyperextension and sticky phenomenon that are likely to occur in the first method, and also in the second method. There is no loss of operability.
[0079]
In the present embodiment, the bending portion 16 is so bent that the bending strength of the second bending portion 40 is smaller than the bending hardness of the flexible tube portion 15 in the vicinity of the connection portion with the flexible tube portion 15. The bending strength of the built-in object disposed inside the tip end portion 17, the filling portion of the built-in object bending portion 16, the filling rate of the tip end portion 17, the bending portion 16, and the flexible tube portion 15 are configured.
[0080]
5B, even when the bending portion 16 is bent by 90 ° or more by the operation of the bending operation knob 30, the relationship between the hardness of the flexible tube portion 15 and the bending portion 16 is as described above. It is constituted similarly.
[0081]
The state where the bending angle of the bending portion 16 is bent to about 90 ° is usually the minimum necessary for putting the distal end portion 17 of the insertion portion 7 into the next lumen when the bending portion of the intestine is exceeded. Is an angle. During the operation of inserting the insertion portion 7 of the endoscope 2 into the large intestine, when the bending portion 16 of the endoscope 2 is passed through the bending portion of the intestine, the bending angle of the bending portion 16 is an angle of 90 ° or more. When the flexible tube portion 15 is pushed in a state with a mark, the direction in which force is applied to the endoscope 2 and the direction in which the distal end portion 17 of the insertion portion 7 faces, that is, the direction in which the distal end portion 17 of the insertion portion 7 is advanced. Will be different. If it exceeds 90 °, the direction is reversed.
[0082]
Therefore, when the flexible tube portion 15 is pushed in this state, a force is applied only in the direction in which the bending portion c pushes the intestinal wall as shown in FIG. Therefore, the intestinal wall excessively extends in the pushed direction, or the flexible tube portion 15 is bent, so-called sticky phenomenon occurs.
[0083]
In the present embodiment, even in the maximum bending state by the operation of the bending operation knob 30 in FIG. 5D, the relationship between the hardness of the flexible tube portion 15 and the bending portion 16 is configured in the same manner as described above. . Therefore, during the operation of inserting the insertion portion 7 of the endoscope 2 into the large intestine, if a force is applied to the flexible tube portion 15 in any state of bending at the bending portion in the large intestine, Even in a state where the bending portion 16 does not slide with the intestinal wall, the second bending portion 40 of the bending portion 16 is deformed before the flexible tube portion 15 starts to bend, and the distal end portion 17 can be reliably advanced.
[0084]
Therefore, the above configuration has the following effects. That is, in the present embodiment, during the operation of inserting the insertion portion 7 of the endoscope 2 into the large intestine, the flexible tube portion 15 is bent at the bent portion in the large intestine, and the force is not transmitted to the distal end portion 17. Therefore, workability when passing the insertion portion 7 of the endoscope 2 through the bent portion in the large intestine is good.
[0085]
A portion near the connection portion of the flexible tube portion 15 with the bending portion 16 is a soft portion 51, and a hard portion (not shown) is provided on the base end side, which is harder than the soft portion 51 in bending in the longitudinal direction. Also good.
[0086]
FIGS. 9A and 9B and FIGS. 10A to 10D show a first modification of the endoscope apparatus 1 according to the first embodiment (see FIGS. 1 to 8). Is. In this modification, the configuration of the bending portion 16 of the endoscope 2 is changed as follows.
[0087]
FIG. 9A shows a maximum bending state in which the bending portion 16 can be bent by the operation stroke of the pulling wire 50 when the bending portion 16 is bent in a single direction. In this modification, when the bending portion 16 is in the maximum bending state, the angle α1 between the axis S1 of the distal end portion of the second bending portion 40 and the center line S2 of the flexible tube portion 15 is set to about 45 ° or less. The bending piece of the bending portion 16 so that the angle α2 between the axis S3 of the distal end portion of the first bending portion 39 and the axis S1 of the distal end portion of the second bending portion 40 is approximately 180 ° or more. 37, strokes of the mesh tube 41, the elastic membrane portion 46, and the pulling wire 50 are set. Here, in this modification, α1 is set to 20 ° and α2 is set to 180 °, respectively, so that a substantially straight natural state along the center line S2 of the flexible tube portion 15 is bent by a total of 200 °. Is formed.
[0088]
When the colon 2 is inspected by the endoscope 2, there is a case where observation of the vicinity of the anus H11 referred to as endorectal reverse vision is performed in the rectum H1. This is because when the insertion portion 7 of the endoscope 2 is inserted into the rectum H1 from the anus H11, the distal end portion 17 of the insertion portion 7 facing the insertion direction is bent by the bending operation of the bending operation knob 30. By bending the angle by more than 0 °, observation is performed with the visual field direction of the endoscope 2 almost opposite to the insertion direction as shown in FIG. 9A.
[0089]
Here, when the angle α1 between the axis S1 of the distal end portion of the second bending portion 40 and the center line S2 of the flexible tube portion 15 is 45 ° or more when the bending portion 16 is in the maximum bending state, FIG. As shown in FIG. 9B, the vicinity of the anus to be observed cannot be observed from the front side. Therefore, when the bending portion 16 is in the maximum bending state as in this modification, the angle α1 between the axis S1 of the distal end portion of the second bending portion 40 and the center line S2 of the flexible tube portion 15 is set to 45 ° or less. By setting, the vicinity of the anus H11 can be observed from the front side as shown in FIG.
[0090]
Next, with reference to FIGS. 10A to 10D, the bending operation when the bending portion 16 shown in FIG. 9A is further bent in the direction orthogonal to the bending direction from the maximum bending state of the bending portion 16 will be described. explain. FIGS. 10A and 10B show the maximum bending state of the bending portion 16 similar to FIG. 9A. In this state, the first bending portion 39 is in contact between the contact portions of most adjacent bending pieces 37. At this time, the second bending portion 40 is not in contact between the contact portions of most adjacent bending pieces 37.
[0091]
From this state, when the bending portion 16 is further bent in the directions of arrows R and L, which are orthogonal to the direction in which the bending is applied, as shown in FIG. Since the bending piece 37 is in contact and in a fixed state, the shape hardly changes. On the other hand, since the bending pieces 37 are not in contact with each other in the second bending portion 40, the bending piece 37 is rotated in the newly bent direction, and the bending shown in FIGS. 10C and 10D is performed. Each is transformed into a shape.
[0092]
Therefore, in this modified example, when observing the vicinity of the anus H11, even if the state shown in FIGS. 10A and 10B is changed to the state shown in FIGS. It is possible to observe the periphery of the object observed in the state of FIGS. 10A and 10B without greatly changing the distance to the observation object. Further, in the present modification, the bending angle of the first bending portion 39 is hardly increased, so that there is an effect that the built-in object of the bending portion 16 is not damaged.
[0093]
In the maximum bending state of the bending portion 16 shown in FIG. 9A, the angle α1 between the axis S1 of the distal end portion of the second bending portion 40 and the center line S2 of the flexible tube portion 15 is 45 ° or more. Even in this case, it is desirable to set it to 90 ° or less.
[0094]
As shown in FIG. 5B, the bending portion 16 is bent at a rotation angle θ1 of approximately 90 ° with respect to the natural state (the direction of the center line O of the insertion portion 7) by the bending operation of the bending operation knob 30. During the bending operation, the second bending portion 40 starts to be bent before the first bending portion 39 is bent to 90 °.
[0095]
Here, the bent part of the large intestine, for example, the Rs bent part H6 shown in FIGS. 11A and 11B and the spleen curved part H8 shown in FIGS. It is. Therefore, at the time of the operation of inserting the insertion portion 7 of the endoscope 2 into the large intestine, the visual field of the distal end portion 17 of the insertion portion 7 is moved beyond the bending portion when the Rs bending portion H6, the splenic bending portion H8, or the like is passed. In order to face the lumen, it is necessary to bend the bending portion 16 at an angle of 90 ° or more. At this time, when the second bending portion 40 is bent, the bending portion 16 is bent when the second bending portion 40 pushes the intestinal wall as shown in FIGS. 11 (B) and 12 (B). Becomes an obtuse angle and the curved portion 16 can be easily passed.
[0096]
Further, in the state shown in FIGS. 6C and 7D, when the bending portion 16 is pressed against the intestinal wall, the second bending portion 40 is already bent in the same direction as the first bending portion 39. Therefore, as shown in FIG. 13, the second bending portion 40 does not bend in the direction opposite to the bending direction of the first bending portion 39.
[0097]
FIG. 14 shows a second modification of the endoscope apparatus 1 according to the first embodiment (see FIGS. 1 to 8). In this modification, the configuration of the bending portion 16 of the endoscope 2 is changed as follows.
[0098]
That is, in this modification, as shown in FIG. 14, the maximum bending angle (rotation angle θ2 with respect to the direction of the center line O of the insertion portion 7) by the operation of the bending operation knob 30 is set to 180 °. The second bending portion 40 is set so as not to start bending.
[0099]
In this case, since the curved shape does not change at all with the conventional widely used endoscope without the second bending portion 40, the operation feeling during the bending operation of the endoscope does not change, There is no sense of incongruity for the surgeon accustomed to the conventional operation method.
[0100]
Further, as shown in FIG. 5C, in the state where the bending portion 16 is bent by approximately 180 ° with respect to the natural state by the operation of the bending operation knob 30, the distal end portion 17 of the insertion portion 7 can be connected to the bending portion 16. You may set to the shape located in the front end side rather than the connection part with the flexible tube part 15. FIG.
[0101]
In this case, each bending portion is inserted in the passage of the sigmoid colon H2 close to the anus H11, which is the insertion port of the insertion portion 7, and in the passage of the SD bending portion H7 which is a transition portion between the sigmoid colon H2 and the descending colon H3. In order to pass through, it is usually not necessary for the bending portion 16 to be bent over 180 °. For this reason, even when the bending portion 16 is bent, the proximal end portion of the bending portion 16 can be gripped.
[0102]
And in insertion of these parts, the curved shape of the 2nd curved part 40 and the 1st curved part 39 can be changed arbitrarily by grasping and bending the 2nd curved part 40. For example, if the second bending portion 40 is bent with a gripped hand while the bending operation knob 30 is bent and the bending operation knob 30 is held, the first bending is performed by the action shown in FIG. The angle of the part 39 becomes an obtuse angle, and if the second bending part 40 is made an obtuse angle, the curved shape of the first bending part 39 changes to an acute angle. In particular, the above operation can be performed from the anus H11 to the rectum H1, and the above operation can be performed from the sigmoid colon H2 to the descending colon H3 by inserting the wall of the bowel while shortening the bowel.
[0103]
Therefore, the above configuration has the following effects. That is, since the curved shape can be adjusted in conjunction with the push-pull operation of the insertion portion 7 with the hand holding the insertion portion 7, the operability is good and the insertion property is good. In addition, there is an effect that the observation visual field can be easily adjusted also in the above-described intrarectal reversal vision.
[0104]
FIGS. 15 and 16 show a second embodiment of the present invention. In the present embodiment, the configuration of the bending portion 16 in the endoscope 2 of the endoscope apparatus 1 according to the first embodiment (see FIGS. 1 to 8) is changed as follows.
[0105]
That is, in the bending portion 16 of the present embodiment, as shown in FIG. 15, contrary to the first embodiment, after the portion of the thin portion 47 of the elastic skin member 42 on the outer peripheral surface of the first bending portion 39. A thick part 48 of the elastic skin member 42 is extended on the end side. Here, the thick part 48 of the elastic skin member 42 is extended to the distal end side by an appropriate length from the boundary part between the part with and without the elastic film part 46 of the mesh tube 41. The length Z2 of the extended portion of the thick portion 48 of the elastic skin member 42 is set to about 5 mm to 15 mm, for example. And the hardness with respect to a bending | hardening with which the part which does not have the elastic film part 46, and the thick part 48 are combined with the part of the length Z2 of the extension part of the thick part 48 of this elastic skin member 42, and the hardness with respect to bending is intermediate | middle hardness (Corresponding to 2 in Table 1) is formed.
[0106]
In the present embodiment, the connecting portion between the first bending portion 39 and the second bending portion 40 of the bending portion 16 is provided with an intermediate hardness portion of the length Z2 that is relatively hard to bending. Therefore, when a bending operation is performed, the proximal end portion of the first bending portion 39 is difficult to bend, and the distal end side of the second bending portion 40 is easily bent, resulting in a curved shape shown in FIG.
[0107]
Therefore, when the bending portion 16 is bent by the bending operation in the bending portion of the large intestine, the shape of the bending portion of the intestine becomes a more obtuse shape than in the first embodiment. In this case, the applied force is easily transmitted to the distal end portion 17 of the insertion portion 7, and the distal end portion 17 of the insertion portion 7 is easily propelled in the insertion direction.
[0108]
Therefore, in the present embodiment, when the insertion portion 7 of the endoscope 2 is inserted into the bent portion of the large intestine, the operation of passing the distal end portion 17 of the insertion portion 7 through the bent portion of the large intestine becomes easier, and the insertability is improved. There is an effect to.
[0109]
Furthermore, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.
Next, other characteristic technical matters of the present application are appended as follows.
Record
(Additional Item 1) In an endoscope apparatus including a distal end portion, a bending portion connected to a proximal end of the distal end portion, and a flexible insertion portion including a flexible tube connected to the proximal end of the bending portion,
The length of the curved portion is formed to be approximately 15 cm or more from the tip,
The bending portion is a first bending portion provided on the distal end side;
An endoscope apparatus comprising: a second bending portion formed to be harder in bending in the axial direction than the first bending portion connected to the proximal end side of the first bending portion.
[0110]
(Additional Item 2) The first bending portion and the second bending portion each include a bending tube member that rotatably connects a plurality of node ring members,
The endoscope apparatus according to Additional Item 1, wherein a resistance member that varies the hardness of the first bending portion and the second bending portion with respect to bending in the axial direction is externally fitted to the bending tube member.
[0111]
(Additional Item 3) The bending portion includes a fitting member that fits the outer periphery of the bending tube member;
It consists of an elastic skin member that covers the outer periphery of the fitted member,
The fitting member has a soft portion on the distal end side and a hard portion on the proximal end side having different hardnesses against bending in the axial direction of the curved portion,
The endoscope apparatus according to additional item 2, wherein the elastic skin member includes a distal-end-side soft portion and a proximal-end-side hard portion having different hardnesses with respect to bending of the bending portion in the axial direction.
[0112]
(Additional Item 4) The hardness change positions of the hard part and the soft part of the fitting member and the hardness change positions of the hard part and the soft part of the elastic skin member are provided at different positions in the axial direction of the bending part. The endoscope apparatus according to appendix 3, characterized by:
[0113]
(Additional Item 5) The endoscope apparatus according to Additional Item 4, wherein the hardness change position of the elastic skin member is provided on the distal end side of the hardness change position of the fitted member.
[0114]
(Additional Item 6) The endoscope apparatus according to Additional Item 4, wherein the hardness change position of the elastic skin member is provided on the base end side with respect to the hardness change position of the fitted member.
[0115]
(Additional Item 7) In the state where the bending portion is bent at least approximately 90 ° or more by the pulling operation of the operation wire by the bending operation means, the hardness of the second bending portion with respect to the axial bending is connected to the second bending portion. The endoscope apparatus according to Additional Item 1, wherein the endoscope apparatus is formed to be smaller than the hardness against bending in the axial direction of the flexible tube.
[0116]
(Additional Item 8) In the maximum bending state of the bending portion that can be bent by the bending operation by the bending operation means,
The endoscope apparatus according to additional item 1, wherein the hardness of the second bending portion with respect to the bending in the axial direction is smaller than the hardness with respect to the bending of the flexible tube connected to the second bending portion in the axial direction.
[0117]
(Additional Item 9) When the bending portion is bent by approximately 180 °,
The endoscope apparatus according to additional item 1, wherein the bending portion is formed such that the position of the distal end portion is positioned on the distal end side in the axial direction with respect to the connection portion between the bending portion and the flexible tube.
[0118]
(Additional Item 10) In an endoscope apparatus having a flexible insertion portion including a distal end portion, a bending portion connected to a proximal end of the distal end portion, and a flexible tube connected to the proximal end of the bending portion,
The bending portion is a first bending portion provided on the distal end side;
A second bending portion formed so that the hardness with respect to bending in the axial direction is harder than the first bending portion connected to the proximal end side of the first bending portion;
The first bending portion and the second bending portion are formed by a bending tube member that rotatably connects a plurality of node ring members,
An operation wire having an end fixed to at least one of the node members of the first bending portion;
In a state where the bending portion is bent approximately 90 ° or more by the pulling operation of the operation wire by the bending operation means,
An endoscope apparatus, wherein the hardness of the second bending portion with respect to the bending in the axial direction is smaller than the hardness with respect to the bending of the flexible tube connected to the second bending portion in the axial direction.
[0119]
(Additional Item 11) In the maximum bending state of the bending portion that can be bent by the pulling operation of the operation wire by the bending operation means, the hardness against the bending in the axial direction of the second bending portion is connected to the second bending portion. It is characterized in that it is formed smaller than the hardness against bending in the axial direction of the flexible tube. Additional Item 10 Endoscopic device.
[0120]
(Prior Art of Additional Items 1-11) Japanese Utility Model Publication No. 1-22641.
[0121]
(Problem to be solved by Supplementary Item 1) In Japanese Utility Model Publication No. 1-22641, since the length of the second bending portion is not considered, it is a connection portion between the second bending portion and the flexible tube. When the relay tube comes close to the bent part in the body cavity, when the flexible tube is pushed from the state shown in FIG. 17A, the force concentrates on the relay tube and pushes the intestinal wall as shown in FIG. 17B. , Overextending the intestines. When the flexible tube is further pushed in, as shown in FIG. 17C, the flexible tube is bent, insertion becomes difficult, and if the cooperative operation for returning the curvature is not performed, the visual field is directed toward the intestinal wall, Cannot be secured.
[0122]
(Additional notes 9 In the configuration of Japanese Utility Model Publication No. 1-22641, it is necessary to coordinate the angle operation with the push-pull or twist operation of the hand holding the insertion portion when inserted into the large intestine. It was difficult to go through complex bends such as the sigmoid colon.
[0123]
(Additional notes 10 In Japanese Utility Model Publication No. 1-22641, a stay coil with a small amount of expansion and contraction is incorporated in the second bending portion, so that when an external force is applied to the second bending portion, The two bending portions cannot be bent freely, and when the bending portion is bent by the bending operation means, a restoring force of the stay coil is generated by the compression or extension of the stay coil due to the bending. The second bending portion is more difficult to bend depending on the external force, and the second bending portion has a change point where the change in hardness with respect to bending is large. It becomes harder than the bending resistance of the flexible tube. For this reason, when the flexible tube is pushed in a curved state during insertion, the flexible tube is bent as shown in FIG. 15C, making insertion difficult.
[0124]
(Operation of Supplementary Item 1) When the bending portion is bent by the operation of the bending operation means, the first bending portion is easily bent, and the second bending portion is difficult to be bent. Therefore, the second bending portion is hardly bent. For this reason, when the bending by an external force is applied in the curved state, the second bending portion can be curved. As a result, when the bending portion is passed through the large intestine, even if the bending portion is pressed against the intestinal wall in a curved state, the second bending portion is bent, so that no force is applied to the intestinal wall. Further, when the connecting portion between the bending portion, which is a hard portion, and the flexible tube approaches the bending portion, the tip portion is introduced into the next bending.
[0125]
(Additional notes 9 The part of the second bending portion can be grasped even in a state where the bending portion is bent for the passage of the bent portion of the intestine from the anus to the rectum. If this is gripped and the second bending portion is bent with the gripped hand, the bending shape of the first bending portion changes in conjunction with this, so the first bending portion of the first bending portion can be operated without operating the bending operation means. The curved shape can be adjusted.
[0126]
(Additional notes 10 When passing through the bent portion of the intestine, even if it is pressed against the intestinal wall with the bent portion bent, the second bent portion is surely bent before the flexible tube begins to bend. Power is not applied.
[0127]
【The invention's effect】
According to the present invention, the first bending portion disposed on the distal end side of the bending portion and the proximal end side of the first bending portion are connected, and the hardness against the bending in the axial direction is higher than that of the first bending portion. And a second bending portion set in a hardened state, and the rear end position of the second bending portion is arranged at a length of about 15 cm or more from the distal end portion of the insertion portion. Thus, it is possible to easily perform the operation of passing the bent portion.
[Brief description of the drawings]
FIG. 1 is an overall schematic configuration diagram of an endoscope apparatus according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view showing an internal configuration of a bending portion of the endoscope in the endoscope apparatus according to the first embodiment.
FIG. 3 is a longitudinal sectional view of a main part showing a connecting portion between a first bending portion and a second bending portion of the bending portion of the endoscope in the endoscope apparatus according to the first embodiment.
FIG. 4 is a schematic configuration diagram showing the structure of a general human large intestine.
FIG. 5 is an explanatory diagram for explaining an operation of a bending portion of the endoscope in the endoscope apparatus according to the first embodiment.
FIG. 6 is an explanatory diagram for explaining an operation of inserting the insertion portion of the endoscope in the rectum, sigmoid colon, and descending colon of the endoscope in the endoscope apparatus according to the first embodiment.
FIG. 7 is an explanatory diagram for explaining an operation of inserting the insertion portion of the endoscope from the descending colon of the large intestine into the transverse colon in the endoscope apparatus according to the first embodiment.
FIG. 8 is an explanatory diagram for explaining the operation of the first bending portion and the second bending portion of the bending portion of the endoscope in the endoscope apparatus according to the first embodiment.
FIG. 9 is an explanatory diagram for explaining the operation of the first modification of the bending portion of the endoscope in the endoscope apparatus according to the first embodiment.
FIG. 10 is an explanatory diagram for explaining the operation of the bending portion of the endoscope according to the first modification.
FIG. 11 is an explanatory diagram for explaining the operation of inserting the insertion portion of the endoscope from the rectum of the large intestine into the sigmoid colon.
FIG. 12 is an explanatory diagram for explaining the action of inserting the insertion portion of the endoscope from the descending colon of the large intestine into the transverse colon.
FIG. 13 is an explanatory diagram for explaining a state in which the second bending portion is bent in a direction opposite to the bending direction of the first bending portion.
FIG. 14 is a front view showing a second modification of the bending portion of the endoscope in the endoscope apparatus according to the first embodiment.
FIG. 15 is a longitudinal sectional view of a main part showing a bending portion of an endoscope in an endoscope apparatus according to a second embodiment of the present invention.
FIG. 16 is an explanatory diagram for explaining the operation of the bending portion of the endoscope in the endoscope apparatus according to the second embodiment.
FIG. 17 is an explanatory diagram for explaining an operation of a bending portion of an endoscope in a conventional endoscope apparatus.
[Explanation of symbols]
2 Endoscope
7 Insertion part
15 Flexible tube
16 Curved part
17 Tip (tip component)
39 1st bending part
40 Second curved portion

Claims

A flexible flexible tube portion having an elongated insertion portion to be inserted into the lumen, a distal end configuration portion disposed at the distal end portion of the insertion portion, and the distal end configuration portion and the distal end portion of the flexible tube portion In an endoscope apparatus formed with a curved portion interposed therebetween,
A state in which the first bending portion disposed on the distal end side of the bending portion and the proximal end side of the first bending portion are connected to each other, and the hardness against the bending in the axial direction is higher than that of the first bending portion. And a second bending portion set to
An endoscope apparatus, wherein a rear end position of the second bending portion is arranged at a length of about 15 cm or more from a distal end portion of the insertion portion.