JP3722633B2

JP3722633B2 - Endoscope

Info

Publication number: JP3722633B2
Application number: JP33445098A
Authority: JP
Inventors: 裕太岡田
Original assignee: Olympus Corp
Current assignee: Olympus Corp
Priority date: 1998-11-25
Filing date: 1998-11-25
Publication date: 2005-11-30
Anticipated expiration: 2018-11-25
Also published as: JP2000162513A

Description

【０００１】
【発明の属する技術分野】
本発明は内視鏡、詳しくは硬質の先端部に観察対象を撮像するための固体撮像素子等を有するいわゆる電子内視鏡に関する。
【０００２】
【従来の技術】
近年、細長の挿入部を体腔内に挿入することにより、切開を必要とすることなく、体腔内の検査対象部位を観察したり、必要に応じて、内視鏡の有する処置具チャンネル内に処置具を挿通して各種治療・処置の行える内視鏡が広く用いられている。
【０００３】
このような内視鏡の一種である電子内視鏡は、挿入部の先端部に観察対象部位の像を結像する観察用レンズと、結像した像を撮像するための固体撮像素子等の撮像手段と、この固体撮像素子から出力される撮像信号を増幅する回路等を構成する回路基板と、増幅された撮像信号等を内視鏡の手元側まで伝送するケーブルの前端部分等を有して構成されており、手元側まで伝送された撮像信号は、外部装置であるビデオプロセッサでモニタ表示可能な画像信号に変換され、モニタ装置に観察像が表示されるようになっている。また、軟性の挿入部を有する内視鏡の先端部の基端側には、手元側からの操作により湾曲自在の湾曲部が一般に連設されており、先端部を所望の向きに向けることができるようになっている。
【０００４】
この種の従来の内視鏡として例えば特開平７−３１５８２号の図４が挙げられる。この例では、内視鏡の先端部の枠体である硬質の先端構成部材に形成された透孔に、観察用レンズ、固定撮像素子及び回路基板が挿入されて固定されており、回路基板から後方にケーブルが延出している。このとき、先端構成部材の後端が、ケーブルの前端より前方に位置しており、回路基板の一部や回路基板とケーブルとの接続部周辺は、先端構成部材から後方に露出して配置されている。
【０００５】
また、他の例として特開平８−５６８９６号が挙げられ、この例では、回路基板の一部及びケーブル前端が、先端構成部材の後端より後方に露出しており、回路基板からケーブル前端にかけて弾性の被覆部材で被覆され、ケーブル・回路基板間にかかる力を軽減し、ケーブル・回路基板間の断線を防いでいる。
【０００６】
【発明が解決しようとする課題】
しかしながら、特開平７−３１５８２号に挙げたような従来の構成では、固体撮像素子或いは回路基板よりも、硬質の先端構成部材の後端面が長手方向前方に位置していたため、先端部後端に連設する湾曲部を湾曲させたとき、大きな曲げの力が前記固体撮像素子や回路基板にかかり、この部分が破損しやすかった。そこで、固体撮像素子及び回路基板を保護するように先端構成部材の後端面の全てを、回路基板の後方に位置するように延ばして形成すると、硬質の先端構成部材が大きくなってしまい、硬質の先端部を小型化しようとする要求に応えられなかった。また、特開平８−５６８９６号に挙げたように、回路基板からケーブルにかけて弾性部材で被覆して保護した場合、ケーブル・回路基板の断線を防ぐことができるが、弾性部材による保護では、湾曲部の湾曲によって回路基板や固体撮像素子にかかる曲げの力を十分に軽減することはできず、これらは破損し易いままであった。
【０００７】
本発明は上記事情に鑑みてなされたものであり、先端部の硬質部分が大きくなることを抑えつつ、固体撮像素子及び回路基板の破損を防止できる内視鏡を提供することを目的とする。
【０００８】
【課題を解決するための手段】
前記目的を達成するため、本発明の第１の内視鏡は、被検体に挿入可能な挿入部と、前記挿入部の先端側を構成し硬質の材料で略円筒状に形成された先端構成部材と、前記先端構成部材に設けられ、撮像素子と前記撮像素子と電気的に接続した回路基板と前記回路基板と接続したケーブルとから成る撮像ユニットを収納する第１の孔部と、前記先端構成部材の基端側に配置され、前記回路基板よりも後ろ側に前記第１の孔部の開口部が設けられる第１の後端面と、前記先端構成部材に設けられ前記挿入部内を挿通する内蔵物を配置するための第２の孔部と、前記先端構成部材の基端側に配置され、前記第２の孔部の開口部が設けられる前記第１の後端面に対して先端側に配置された第２の後端面と、を具備したことを特徴とする。
本発明の第２の内視鏡は、被検体に挿入可能な挿入部と、前記挿入部の先端側を構成し硬質の材料で略円筒状に形成された先端構成部材と、前記先端構成部材に設けられ、撮像素子と前記撮像素子と電気的に接続した回路基板と前記回路基板と接続したケーブルとから成る撮像ユニットを収納する第１の孔部と、前記先端構成部材の基端側に配置され、前記回路基板よりも後ろ側に前記第１の孔部の開口部が設けられる第１の後端面と、前記先端構成部材に設けられ前記挿入部内を挿通する鉗子チャンネルを配置するための第２の孔部と、前記先端構成部材の基端側に配置され、前記第２の孔部の開口部が設けられる前記第１の後端面に対して先端側に配置された第２の後端面と、を具備したことを特徴とする。
本発明の第３の内視鏡は、被検体に挿入可能な挿入部と、前記挿入部の先端側を構成し硬質の材料で略円筒状に形成された先端構成部材と、前記先端構成部材に設けられ、撮像素子と前記撮像素子と電気的に接続した回路基板と前記回路基板と接続したケーブルとから成る撮像ユニットを収納する第１の孔部と、前記先端構成部材の基端側に配置され、前記回路基板よりも後ろ側に前記第１の孔部の開口部が設けられる第１の後端面と、前記先端構成部材に設けられ前記挿入部内を挿通するライトガイドを配置するための第２の孔部と、前記先端構成部材の基端側に配置され、前記第２の孔部の開口部が設けられる前記第１の後端面に対して先端側に配置された第２の後端面と、を具備したことを特徴とする。
本発明の第４の内視鏡は、被検体に挿入可能な挿入部と、前記挿入部の先端側を構成し硬質の材料で略円筒状に形成された先端構成部材と、前記先端構成部材に設けられ、撮像素子と前記撮像素子と電気的に接続した回路基板と前記回路基板と接続したケーブルとから成る撮像ユニットを収納する第１の孔部と、前記先端構成部材の基端側に配置され、前記回路基板よりも後ろ側に前記第１の孔部の開口部が設けられる第１の後端面と、前記先端構成部材に設けられ前記挿入部内を挿通する送気送水用の管路パイプを配置するための第２の孔部と、前記先端構成部材の基端側に配置され、前記第２の孔部の開口部が設けられる前記第１の後端面に対して先端側に配置された第２の後端面と、を具備したことを特徴とする。
【０００９】
【発明の実施の形態】
以下、図面を参照して本発明の実施の形態を説明する。
（第１の実施の形態）◎
図１ないし図６は本発明の第１の実施の形態に係り、図１は内視鏡装置の全体構成を示す説明図、図２は先端部及び湾曲部前端側の構成を示す断面図、図３は図２のＡ−Ａ断面図、図４は図３のｄ１−ｄ２−ｄ３−ｄ４−ｄ５断面図、図５は図２のＢ−Ｂ断面図、図６は図３のｅ−ｅ断面図である。
【００１０】
（構成）
図１に、本実施の形態の内視鏡２を有して構成される内視鏡装置１の構成を示す。
内視鏡２は、操作者がこの内視鏡２を把持し操作するための操作部１３と、この操作部１３先端側に連設され体腔内等の観察対象部位へ挿入する挿入部１０１と、操作部１３側部から延出し外部装置へ接続するためのユニバーサルコード１４と、このユニバーサルコード１４の端部に備えられ観察対象部位を照明する照明光を発する光源装置３に着脱自在に接続するためのライトガイドコネクタ１５と、このライトガイドコネクタ１５側部から延出し挿入部先端に備えられた後述する固体撮像素子からの撮像信号に後述する信号処理を施すビデオプロセッサ４に着脱自在に接続する信号コネクタ１７を端部に備えた信号ケーブル１６等から主に構成される。
【００１１】
挿入部１０１は、操作部１３先端に連設された可撓性を有する細長の可撓管部１２と、この可撓管部１２先端に連設された湾曲自在の湾曲部１９と、この湾曲部１９先端に連設された先端部１８から構成されている。
【００１２】
内視鏡２内には、挿入部１０１、操作部１３、ユニバーサルコード１４、ライトガイドコネクタ１５内を挿通する照明光を導光するためのライトガイド１１が備えられている。このライトガイド１１の光入射端は、ライトガイドコネクタ１５に取り付けられており、光源装置３に備えられた光源ランプ９から発せられ集光レンズ１０で集光された照明光が、ライトガイド１１の光入射端に入射するようになっている。この照明光は、ライトガイド１１で導光され、先端部１８に取り付けられたライトガイド１１の光出射端から出射し、観察対象部位を照明するようになっている。
【００１３】
照明光で照明された観察対象部位からの反射光による観察像は、先端部１８に備えられたここでは図示しない固体撮像素子２２で撮像され、この固体撮像素子２２から出力される撮像信号は、挿入部１０１、操作部１３、ユニバーサルコード１４、ライトガイドコネクタ１５、信号ケーブル１６、信号コネクタ１７内を挿通するここでは図示しないケーブル３０を介して、ビデオプロセッサ４へ伝送されるようになっている。
【００１４】
ビデオプロセッサ４は、固体撮像素子２２からの撮像信号をモニタ表示可能な画像信号に変換する信号処理を行い、この画像信号をモニタ装置５へ出力する。これにより、モニタ装置５は、固体撮像素子２２で撮像した観察像を表示するようになっている。また、ビデオプロセッサ４には、観察像を画像記録するためのＶＴＲデッキ６及びビデオディスク７、観察像を印刷するためのビデオプリンタ８が接続されており、ビデオプロセッサ４は、固体撮像素子２２からの撮像信号をこれらの機器に出力するための画像信号に変換する機能を有している。
【００１５】
前記挿入部１０１を例えば体腔内等に挿入して観察対象を観察していると、先端部１８内のライトガイド１１光出射端の前方や固体撮像素子２２の前方に備えられた光学系の露出部分に例えば体液等が付着し、照明光の光量が減少したり、観察像が見えなくなってしまうので、内視鏡２は、光学系の露出面を洗浄する機能を有している。操作部１３側部には、図示しない送気・送水ポンプを接続するための送気・送水口２０ｂが設けられており、この送気・送水口２０ｂは、操作部１３、挿入部１０１内を挿通するここでは図示しない送気・送水チューブ４８を介して先端部１８から突出したここでは図示しない洗浄用ノズル２３に連通しており、この洗浄用ノズル２３から空気や水を光学系の露出面に噴射することで、光学系の露出面を洗浄できるようになっている。
【００１６】
内視鏡２は、観察対象部位の観察像を得るばかりでなく、観察対象部位である例えば体腔内の生体組織を採取したり処置を施すことができるようになっている。操作部１３側部には、観察対象部位に処置を施すための図示しない鉗子等の処置具を挿入するための鉗子挿入口２０ａが設けられており、この鉗子挿入口２０ａから挿入された処置具は、操作部１３、挿入部１０１内を挿通するここでは図示しない鉗子チャンネル２４内を挿通して先端部１８から突出し、これにより観察対象部位に処置を施すことができるようになっている。
【００１７】
図２を使用して、本実施の形態の内視鏡２が特徴を有する先端部１８及び湾曲部１９先端の構成を説明する。
先端部１８の枠体は、金属で略円筒状に形成された先端構成部材２７からなる。先端構成部材２７には、先端部１８の内蔵物を収納するための複数の透孔が長手方向に形成されている。
先端部１８基端側には、湾曲部１９が連設されている。この湾曲部１９は、複数の湾曲駒がピン等で互いに回動自在に接続されている。最も先端側の第１湾曲駒５７と続く第２湾曲駒５８とは、湾曲ピン５９にて接続され、第１関節６０が構成されている。続く複数の関節も同様の構成となっている。湾曲部１９先端には、操作部１３の図示しない湾曲操作レバーから、操作部１３、可撓管部１２、湾曲部１９内を挿通する湾曲ワイヤー６１が延びている。この湾曲ワイヤー６１先端は、第１湾曲駒５７内周の第１関節６０より前端寄りの位置に取り付けられた略円筒状の湾曲ワイヤー固定部材１９ｃに固定されている。これにより、操作部１３の湾曲操作レバーで湾曲ワイヤー６１を牽引操作することで、湾曲部１９を湾曲操作することができるようになっている。
第１湾曲駒５７は、前方に長く形成されており、この部分を先端構成部材２７後端外周に外嵌させることで、先端構成部材２７と第１湾曲駒５７とが一体的に取り付けられている。つまり、湾曲ワイヤー６１を牽引操作することで、先端部１８を所望の向きに向けることができるようになっている。
第１湾曲駒５７、第２湾曲駒５８、…、といった湾曲駒の外周は、金属製の網状管１９ａで覆われ、第１関節６０より前端寄りに位置する網状管１９ａの前端は、例えば半田１９ｂで第１湾曲駒５７外周に固定されている。
先端構成部材２７の前端外周は、絶縁性の材料で形成された先端カバー２８で覆われている。先端カバー２８後端から後方の先端部１８及び湾曲部１９の外周は、ゴム等で形成された被覆部材１２ｂで覆われており、この被覆部材１２ｂ先端は、例えば緊縛糸や接着剤で先端構成部材２７外周に固定されている。
先端カバー２８には、先端構成部材２７の透孔に対応する位置に、透孔が形成されている。
【００１８】
図２及び図４及び図６を使用して、先端構成部材２７に形成されている先端部１８内蔵物を収納するための透孔の構成を説明する。
図２に示すように、先端構成部材２７には、ライトガイド１１及びこれに関わる光学系を収納するためのライトガイド用透孔３５ｂ、固体撮像素子２２及びこれに関わる部材を収納するための固体撮像素子用透孔３５ａが形成されている。また、図４に示すように、先端構成部材２７には、送気・送水チューブ４８や洗浄用ノズル２３に関わる部材を取り付けるための送気・送水用透孔３５ｃが形成されている。また、図６に示すように、先端構成部材２７には、鉗子チャンネル２４先端を構成する鉗子チャンネル用透孔３５ｄが形成されている。
【００１９】
次に、固体撮像素子用透孔３５ａに収納される部材等の構成を説明する。
図２に示すように、固体撮像素子用透孔３５ａ先端には、複数の観察用レンズ２１を内周に組み付けたレンズ枠３２が取り付けられている。
このレンズ枠３２より後方の固体撮像素子用透孔３５ａは太径に形成されており、レンズ枠３２後端には、固体撮像素子２２が取り付けられている。
固体撮像素子２２の後方には、この固体撮像素子２２にリード接続し信号増幅回路等を構成する電子部品を搭載した回路基板２９が配設されている。
回路基板２９からは、撮像信号をビデオプロセッサ４に伝送するケーブル３０が延出しており、このケーブル３０は、挿入部１０１、操作部１３、ユニバーサルコード１４、ライトガイドコネクタ１５、信号ケーブル１６を介し、信号コネクタ１７に接続されている。
ケーブル３０は、図３に示すように、複数の小ケーブル３３のうち数本を束ねて樹脂チューブ３４で覆うことで構成されている。また、この樹脂チューブ３４に覆われない例えば電源用ケーブルやグランド用ケーブル等の小ケーブル３３もケーブル３０と平行して信号コネクタ１７に接続されている。
レンズ枠３２後端付近からケーブル３０前端付近までの範囲には、固体撮像素子２２及び回路基板２９を覆うようにして、熱収縮チューブ３１が設けられている。
【００２０】
固体撮像素子用透孔３５ａ及びこの周辺部において、先端構成部材２７の後端面４１ａは、ケーブル３０の樹脂チューブ３４の前端であるケーブル前端４２より後側に位置するように形成されている。
また、固体撮像素子用透孔３５ａと熱収縮チューブ３１やケーブル３０との隙間には、ＲＴＶシリコーンゴムなどの弾性部材５６が充填されている。また、弾性部材５６は、硬化後も弾性の接着剤であってもよい。
【００２１】
次に、ライトガイド用透孔３５ｂの構成を説明する。
図２に示すように、ライトガイド用透孔３５ｂの先端には、ライトガイド１１から出射される照明光を配光するための照明用レンズを内周に取り付けたレンズ枠２６が嵌合している。レンズ枠２６の後端には、ライトガイド１１の端部が嵌入されている。
このライトガイド用透孔３５ｂの形成された位置において、先端構成部材２７の後端は、後端面４１ｂとなっている。
【００２２】
次に、送気・送水用透孔３５ｃの構成を説明する。
図４に示すように、送気・送水用透孔３５ｃの先端は太径に形成されており、この部分に、洗浄用ノズル２３が嵌合している。洗浄用ノズル２３の出射口は、送気・送水用透孔３５ｃから略９０度曲げられており、照明用レンズ２５等の先端部１８から露出した光学系の面に向けて出射するようになっている。
送気・送水用透孔３５ｃの後端には、送気・送水チューブ４８を接続するための管路パイプ４７が嵌合しており、この管路パイプ４７後端には、送気・送水チューブ４８が嵌合している。この管路パイプ４７は、途中で曲げられており、先端構成部材２７の後側での管路パイプ４７と他の内蔵物との干渉を避ける形状となっている。
また、送気・送水用透孔３５ｃの後端には、座ぐり穴４９が形成されており、この座ぐり穴４９の底面が送気・送水用透孔３５ｃの後端面４１ｃとなっている。この座ぐり穴４９内には、管路パイプ４７後部の曲げ部が位置している。この座ぐり穴４９を形成することにより、管路パイプ４７をより前側に位置させることができる。管路パイプ４７をより前側に位置させることができるので、送気・送水チューブ４８の前端を湾曲部１９の第１関節６０から離した位置に配することができ、湾曲部１９湾曲時に管路パイプ４７後端に接続される送気・送水チューブ４８が曲げられても、曲率半径が大きくなるので送気・送水チューブ４８にかかる負担が減少し、耐性が向上する。
図５に示すように、洗浄用ノズル２３を固定するための絶縁性材料で形成されたノズル抜け止めピン３９が、先端カバー２８及び先端構成部材２７に連通した横穴に挿入されている。ノズル抜け止めピン３９の後端は平面となっており、また、ノズル抜け止めピン３９に対応する位置の先端カバー２８の側面も平面となっており、ノズル抜け止めピン３９の後端の平面と同面になっている。ノズル抜け止めピン３９の後端が平面であるので、ノズル抜け止めピン３９を加工し易いという利点がある。
【００２３】
次に鉗子チャンネル用透孔３５ｄの構成を説明する。
図６に示すように、鉗子チャンネル用透孔３５ｄの後端面４１ｄから前方に向けて、鉗子チャンネル２４を構成するチャンネルチューブ２４ｂを接続するための接続管２４ａが嵌合され、この接続管２４ａの後端にチャンネルチューブ２４ｂが嵌合されている。チャンネルチューブ２４ｂの外周は、金属で形成された螺旋管２４ｃで覆われ、内部に挿通する処置具に対する強度を確保している。
鉗子チャンネル用透孔３５ｄの後端面４１ｄより後方では、先端構成部材２７或いは先端構成部材２７に外嵌した第１湾曲駒５７前側部と、接続管２４ａに外嵌したチャンネルチューブ２４ｂとの隙間に、粘性のＲＴＶシリコーンゴム等で形成された弾性部材５６が配設されている。これにより、チャンネルチューブ２４ｂが抜けることを防止し、また、湾曲部１９湾曲時にチャンネルチューブ２４ａにかかる曲げの力を吸収し、鉗子チャンネル２４を構成するチャンネルチューブ２４ａの耐性を向上させている。
【００２４】
次に、以上説明した固体撮像素子用透孔３５ａ、ライトガイド用透孔３５ｂ、送気・送水用透孔３５ｃ、鉗子チャンネル用透孔３５ｄのそれぞれの後端面４１ａ、４１ｂ、４１ｃ、４１ｄの長手方向の位置関係を説明する。
先端構成部材２７の後端面は、先端側から鉗子チャンネル用透孔３５ｄの後端面４１ｄ、送気・送水用透孔３５ｃの後端面４１ｃ、ライトガイド用透孔３５ｂの後端面４１ｂ、固体撮像素子用透孔３５ａの後端面４１ａの順となるように形成されている。
先端構成部材２７の後端面４１ａ、４１ｂ、４１ｃ、４１ｄは、硬質の先端部１８に対する短小化の要求や湾曲部１９湾曲時の内蔵物の耐性向上の要求から、できる限り前方に位置させる。ただし、固体撮像素子用透孔３５ａの後端面４１ａは、固体撮像素子２２及び回路基板２９を保護するために、回路基板２９の後方に位置させる。観察用レンズ２１、固体撮像素子２２、回路基板２９、回路基板２９とケーブル３０の接続部は、先端部１８の長手方向に長く配されるので、後端面４１ａは後方に形成され、例えば図３に示す断面の位置では、固体撮像素子用透孔３５ａ周囲のみに先端構成部材２７が存在し、他の透孔は存在しないようになっている。これにより、湾曲部１９湾曲時の固体撮像素子２２及び回路基板２９の破損を防いでいる。
同様に、他の透孔も各透孔に収納される内蔵物により、各透孔の後端面の位置が異なっている。これにより、湾曲部１９湾曲時の先端部１８の各内蔵物の破損を防ぎつつ、先端構成部材２７の長さを短くしている。
【００２５】
次に、固体撮像素子用透孔３５ａと鉗子チャンネル２４との径方向の位置関係を説明する。
図２に示すように、固体撮像素子用透孔３５ａは、固体撮像素子２２が収納される位置では、固体撮像素子２２よりも一回り大きく形成されており、先端構成部材２７と固体撮像素子との間には隙間ができる。図３に示すように、この隙間は、固体撮像素子２２の中心から見て、鉗子チャンネル２４が位置する側の隙間ｔ２より、反対側にできる隙間ｔ１の方が大きくなっている。鉗子チャンネル２４は内視鏡挿入方向において均一の外径ではなく、一部に太い径の最大外径部が形成されている。そこで、固体撮像素子２２を先端構成部材２７に組み付ける際には、鉗子チャンネル２４とは反対側の隙間に固体撮像素子２２を逃しながら鉗子チャンネル２４の最大外径部を通過させ、その後、鉗子チャンネル２４側に固体撮像素子２２を寄せることで、鉗子チャンネル２４と固体撮像素子２２の間隔を小さくしても、組立を行うことができる。一般的に、先端部１８等はできるだけ細い方が望ましく、固体撮像素子用透孔３５ａと鉗子チャンネル２４との間隔を小さく形成することで、先端部１８をより細径化できる。
【００２６】
（作用）
本実施の形態の作用を述べる。
先端構成部材２７の固体撮像素子用透孔３５ａの後端面４１ａが、ケーブル前端４２より後端側にまで延びるように形成されているので、固体撮像素子２２及び回路基板２９の周囲が硬質の金属で形成された先端構成部材２７で覆われている。固体撮像素子２２及び回路基板２９の周囲が先端構成部材２７で覆われていないと、固体撮像素子２２及び回路基板２９は、熱収縮チューブ３１で覆われているだけなので、一般的に外力特に湾曲部１９湾曲時等の挿入軸に垂直な方向にかかる曲げ力に弱くなってしまう。しかし、本実施の形態では、わずかに隙間を確保しつつ先端構成部材２７で覆う構造としたので、曲げの力を先端構成部材２７が吸収し、固体撮像素子２２及び回路基板２９の破損を防止できる。また、一般に挿入部１０１の各内蔵物は、その先端を先端構成部材２７に固定されており、内蔵物の先端構成部材２７より後方の位置に配される部分は、湾曲部１９を湾曲させる要求から軟性を有するように構成されている。このとき、先端構成部材２７の後端面と湾曲部１９の第１関節６０までの距離が短いと、第１関節６０前方での各内蔵物の軟性部分が短く、湾曲部１９湾曲時には各内蔵物が第１関節６０によって急激に曲げられるので耐性が低くなってしまう。また、これを避けるために、第１関節６０を後方に移動し、先端構成部材２７の後端面と第１関節６０との距離を広げると、硬質の先端部１８が長くなってしまう。しかし、本実施の形態では、固体撮像素子２２及び回路基板２９の収納される固体撮像素子用透孔３５ａの後端面４１ａのみを後方に伸ばし、他の内蔵物が位置する先端構成部材２７の後端面４１ｂ、４１ｃ、４１ｄはそのまま前方に留置させたので、硬質の先端部１８が長くなることを抑えつつ、固体撮像素子２２及び回路基板２９の破損を防止している。
【００２７】
（効果）
以上述べた本実施の形態によれば、以下の効果を得ることができる。
観察対象部位に挿入する細長の挿入部１０１と、可撓管部１２の先端に位置する先端部１８の枠体である硬質の先端構成部材２７と、前記先端構成部材２７に組み付けられた前記観察対象部位を撮像するための固体撮像素子２２と、前記先端構成部材２７に組み付けられた前記固体撮像素子２２から出力される信号を増幅する回路等を構成する電子部品を搭載した回路基板２９と、前記回路基板２９に接続した前記回路基板２９から出力される信号を前記挿入部１０１内を挿通して手元側まで伝送するケーブル３０と、を有する内視鏡２であって、前記固体撮像素子２２及び前記回路基板２９の周囲を覆い、前記回路基板２９の後端もしくは前記ケーブル３０の前端より挿入部長手方向後側に後端が位置するように前記先端構成部材２７の後部に形成されたもしくは前記先端構成部材２７の後部に取り付けられた硬質部材を具備したことにより、前記固体撮像素子２２及び前記回路基板２９の周囲のみ前記硬質部材で覆い、前記先端構成部材２７全体が後方に延びることを抑え、先端部１８の硬質部分が大きくなることを抑えつつ、固体撮像素子２２及び回路基板２９の破損を防止できる。
【００２８】
（第２の実施の形態）
図７は本発明の第２の実施の形態に係り、先端部の構成を示す断面図である。なお、本実施の形態で述べない部位の構成は、第１の実施の形態と同様の構成である。
【００２９】
（構成）
図７に示すように、先端構成部材２７の固体撮像素子用透孔３５ａには、先端側から観察用レンズ２１、固体撮像素子２２、回路基板２９、ケーブル３０が組み付けられており、ケーブル前端４２は、固体撮像素子用透孔３５ａの後端面４１ａより後方にはみ出して配されている。この固体撮像素子用透孔３５ａの後端面４１ａは、例えばライトガイド用透孔３５ｂの後端面４１ｂと長手方向同位置になるように形成されていてもよい。また、後端面４１ａは、図に示すより前方で、回路基板２９後方の位置に形成されていてもよい。
固体撮像素子用透孔３５ａの後端には、金属製のパイプ３６が嵌合されており、このパイプ３６の後端は、ケーブル前端４２より後方に位置するように組み付けられている。なお、パイプ３６とケーブル３０の隙間には、第１実施の形態のように弾性部材５６を充填してもよい。
【００３０】
（作用）
本実施の形態の作用を述べる。
湾曲部１９湾曲時には、挿入方向に略直交した方向に曲げ方向の力がかかる。固体撮像素子２２及び回路基板２９及びケーブル３０前端の一部が、硬質の金属製のパイプ３６で覆われており、パイプ３６と内蔵物との間にわずかな隙間を確保してあるので、固体撮像素子２２及び回路基板２９にかかる曲げ方向の力は金属製のパイプ３６により軽減され、固体撮像素子２２及び回路基板２９の破損を防ぐことができる。
【００３１】
（効果）
以上述べた本実施の形態によれば、湾曲部１９湾曲時に固体撮像素子２２及び回路基板２９にかかる曲げ力を、第１の実施の形態の先端構成部材２７の代わりに、金属製のパイプ３６が受けるため、固体撮像素子２２及び回路基板２９の破損を防ぐことができ、結果として第１の実施の形態と同様の効果を得られる。
【００３２】
また、観察用レンズ２１、固体撮像素子２２、回路基板２９を長手方向の長さの異なるものに組み替える場合に、同一の先端構成部材２７を使用して、パイプ３６のみを長さの異なるものに組み替えるのみで対応することができ、内蔵する観察用レンズ２１や固体撮像素子２２や回路基板２９の寸法に関する柔軟性が向上する。
【００３３】
（第３の実施の形態）
図８ないし図１０は本発明の第３の実施の形態に係り、図８は先端部の構成を示す断面図、図９は図８のＢ−Ｂ断面図、図１０は図８のＣ−Ｃ断面図である。なお、本実施の形態で述べない部位の構成は、第１の実施の形態と同様の構成である。
【００３４】
（構成）
図８に示すように、先端部１８の枠体である先端構成部材２７には、固体撮像素子用透孔３５ａ、ライトガイド用透孔３５ｂ、送気・送水用透孔３５ｃ等の透孔が形成されている。先端構成部材２７先端には、先端カバー２８が嵌合しており、先端カバー２８には、先端構成部材２７に形成された各透孔の位置に対応して透孔が形成されている。
固体撮像素子用透孔３５ａには、先端側から観察用レンズ２１を固定するレンズ枠３２、固体撮像素子２２、回路基板２９、ケーブル３０が組み付けられている。
ライトガイド用透孔３５ｂには、先端側から照明用レンズ２５、ライトガイド１１の先端部分が組み付けられている。
送気・送水用透孔３５ｃには、先端部１８先端面から突出するように洗浄用ノズル２３が取り付けられ、後端側には、管路パイプ４７を介して送気・送水チューブ４８が組み付けられている。
【００３５】
図９に示すように、先端構成部材２７外周に形成された溝及びこの溝に連通する先端カバー２８に形成された穴に、先端カバー抜け止めピン３８を挿入することで、先端カバー２８の先端構成部材２７からの脱落が防止されている。
また、観察用レンズ２１のレンズ枠３２は、先端構成部材２７に形成されたネジ部にビス３７を締め付けることで、先端構成部材２７に固定されている。ビス３７は、固体撮像素子用透孔３５ａと送気・送水用透孔３５ｃとの間の先端構成部材２７周縁に位置している。
図８及び図１０に示すように、洗浄用ノズル２３外周には、図１０に示す断面内で凹状の溝部３９ａが形成されており、この溝部３９ａに対応する位置に形成された先端構成部材２７の穴及び先端カバーの穴を通してノズル抜け止めピン３９を突き当てることにで、洗浄用ノズル２３の脱落が防止されている。このノズル抜け止めピン３９は、固体撮像素子用透孔３５ａと送気・送水用透孔３５ｃとの間の先端構成部材２７周縁に位置している。
図９及び図１０を重ね合わせてみると、図９内のビス３７と、図１０内のノズル抜け止めピン３９とは、挿入方向から見た場合に重なり合う位置つまり長手方向軸からの相対位置が略等しい位置に配されている。
【００３６】
（作用）
本実施の形態の作用を述べる。
一般に先端部１８の各内蔵物間の距離を小さくしていくことで、先端部１８の細径化が図られる。しかし、洗浄用ノズル２３と観察用レンズ２１の間の距離をある限界より小さくすると、観察視野内に洗浄用ノズル２３が映ってしまう現象いわゆる視野ケラレが生じてしまい、これを避けるために洗浄用ノズル２３と観察用レンズ２１との間にある大きさ以上の隙間を一般に確保している。つまり、視野ケラレを避けるために、固体撮像素子用透孔３５ａと送気・送水用透孔３５ｃとの間には、ある大きさ以上の間隔がそもそも確保されている。
一方、先端部１８には、観察用レンズ２１を保持するレンズ枠３２を固定するためのビス３７及び洗浄用ノズル２３を固定するためのノズル抜け止めピン３９を配設するスペースを一般に確保する必要がある。
そこで、本実施の形態では、固体撮像素子用透孔３５ａと送気・送水用透孔３５ｃとの間に確保されている先端構成部材２７の肉厚部分に、ビス３７及びノズル抜け止めピン３９を配設した。これにより、ビス３７及びノズル抜け止めピン３９を配設するためのスペースを先端構成部材２７に改めて確保しなくてもよい。これにより、先端部１８の外径を大きくすることなく、洗浄用ノズル２３や観察用レンズ２１を保持するレンズ枠３２といった内蔵物を固定することができる。
【００３７】
（効果）
本実施の形態によれば、洗浄用ノズル２３と観察用レンズ２１との間にそもそも確保される先端構成部材２７の肉厚部分に、長手方向にずらして観察用レンズ２１を保持するレンズ枠３２を固定するビス３７と洗浄用ノズル２３を固定するためのノズル抜け止めピン３９を配設するようにしたので、先端部１８の外径を大きくすることなく、先端部１８の内蔵物である洗浄用ノズル２３や観察用レンズ２１を保持するレンズ枠３２といった内蔵物を固定することができる。
【００３８】
なお、先端カバー抜け止めピン３８とビス３７を長手方向にずらして、挿入方向から見て重なる位置にビス３７、先端カバー抜け止めピン３８、ノズル抜け止めピン３９の３つを配してもよい。また、本実施の形態とは異なる他の内蔵物を固定するための少なくとも２つのビスやピンを設ける構成としてもよい。また、ノズル抜け止めピン３９は、ビス３７と同じ構造のものであってもよい。
【００３９】
（第４の実施の形態）
図１１ないし図１２は本発明の第４の実施の形態に係り、図１１は先端部を前方から見た図、図１２は図１１のｃ−ｃ断面図である。なお、本実施の形態で述べない部位の構成は、第１の実施の形態と同様の構成である。
【００４０】
（構成）
図１１に示すように、先端部１８には内蔵物を収納する複数の透孔が形成されており、先端部１８先端面には、観察用レンズ２１、照明用レンズ２５、鉗子チャンネル２４、洗浄用ノズル２３が配設されている。照明用レンズ２５は、レンズ枠２６に嵌挿されて固定された複数のレンズから構成されている。
図１２に示すように、略円筒状に形成されたレンズ枠２６の先端側外周には、径方向に突出した鍔部４３が形成されている。鍔部４３は、全周に形成されているのではなく、外周の一部に形成されている。
先端構成部材２７にレンズ枠２６を前方より挿入すると、鍔部４３が先端構成部材２７と突き当たり、レンズ枠２６と先端構成部材２７との相対位置が決まるようになっている。これにより、照明用レンズ２５と先端構成部材２７との相対位置、また、照明用レンズ２５と先端構成部材２７の先端に取り付けられた先端カバー２８との相対位置が決まるようになっている。
【００４１】
（作用）
照明用レンズ２５が嵌挿されたレンズ枠２６を先端構成部材２７に前方より挿入すると、鍔部４３が先端構成部材２７の前面に突き当たる。これにより、レンズ枠２６と先端構成部材２７との相対位置が決まる。レンズ枠２６と最前端の照明用レンズ２５先端面との位置、及び先端構成部材２７と先端カバー２８の前面との位置をそれぞれ予め決めておけば、レンズ枠２６の鍔部４３と先端構成部材２７を突き当てることにより、最前端の照明用レンズ２５先端面と先端カバー２８前面との相対位置を決めることができる。通常、先端カバー２８前面より僅かに前方に照明用レンズ２５先端面が突出するように照明用レンズ２５先端面と先端カバー２８前面との相対位置は決められる。鍔部４３が全周に形成されていると、鍔部４３を挿入できるように、前記先端カバー２８に前記鍔部４３と同径の穴をあける必要がある。こうすると、先端カバー２８に形成された照明用レンズ２５を保持するレンズ枠２６を挿入するための孔と他の内蔵物を収納するための孔との間の先端カバー２８の肉厚が小さくなり、また、レンズ枠２６を挿入する孔と先端カバー２８側部との間の肉厚も小さくなる。すると、先端カバー２８は、絶縁のために、硬質プラスチック等の金属に比べて破損しやすい材料で形成されているので肉切れを起こしたり、先端部１８に衝撃が加わった際に破損し易かった。本実施の形態のように、前記レンズ枠２６の鍔部４３を全周でなく外周の一部のみに形成すれば、先端カバー２８にあける孔も一部だけ大きくした異形孔でよく、全周に鍔部４３を形成したときより先端カバー２８に形成する孔の大きさは小さくてすむ。そのため、先端カバー２８の各内蔵物間の肉厚を大きく確保することができ、先端部１８径を大きくすることなく、先端カバー２８の破損を防ぐことができる。
【００４２】
（効果）
以上述べた本実施の形態によれば、先端構成部材２７に突き当てて先端構成部材２７に対する照明用レンズ２５の位置決めをするためのレンズ枠２６外周に形成された鍔部４３をレンズ枠２６外周の全周ではなく一部に形成したので、レンズ枠２６を挿入するための先端カバー２８に形成する孔を小さくすることができ、先端部１８径を大きくすること無く、先端カバー２８の破損を防ぐことができる。
【００４３】
（第５の実施の形態）
図１３は本発明の第５の実施の形態に係り、図１１の矢印方向から洗浄用ノズルの開口部を拡大して見た図である。なお、本実施の形態で述べない部位の構成は、第１の実施の形態と同様の構成である。
【００４４】
（構成）
図１３に示すように、洗浄用ノズル２３の開口部４４は、屋根部４５と両側の側部４６からなっている。
先端カバー２８の前面からの前記屋根部４５の高さは、中央部付近の高さａと側部付近の高さｂとでは異なっており、ａ＜ｂとなっている。
【００４５】
（作用）
本実施の形態の作用を述べる。
洗浄用ノズル２３の開口部４４の大きさは大きいほどつまりにくい。本実施の形態では、一般につまり易い部位である開口部４４の側部４６付近において、屋根部４５の高さを高くしているのでつまりにくい。また、洗浄用ノズル２３の屋根部４５の中央付近を低くしたので、送水時の噴出流の流速は速いままであり、洗浄性を損ねない。
【００４６】
（効果）
本実施の形態によれば、洗浄用ノズル２３からの送水の流速を小さくすることなく、ノズルつまりを起こりにくくすることができる。
【００４７】
（第６の実施の形態）
図１４ないし図１５は本発明の第６の実施の形態に係り、図１４は先端構成部材と湾曲部との接続部分の構造を示す断面図、図１５は図１４を拡大して示した断面図である。なお、本実施の形態で述べない部位の構成は、第１の実施の形態と同様の構成である。
【００４８】
（構成）
図１４は、先端部１８の先端構成部材２７と湾曲部１９の第１湾曲駒５７との接続部分を拡大した断面図である。
先端構成部材２７外周後部側には、前方に長く延びた第１湾曲駒５７が嵌合されている。
先端構成部材２７外周には穴５５ｂが形成されており、また、この先端構成部材２７の穴に対応する第１湾曲駒５７の位置には孔５５ａが形成されており、先端構成部材２７と第１湾曲駒５７とを嵌合させると、穴５５ｂと孔５５ａとの位置が略一致し、これらが連通するようになっている。
先端構成部材２７の周部には、第１湾曲駒５７の前端面が突き当てられる段差５５ｃが形成されており、孔５５ａの中心は、第１湾曲駒５７の前端から距離ａの位置に形成され、穴５５ｂの中心は、段差５５ｃから距離ｂの位置に形成されており、このとき、ａ＞ｂとなっている。つまり、孔５５ａと穴５５ｂとは完全に同位置に形成されているのではなく、長手方向にずらして形成されている。◎図１５に示すように、穴５５ｂには、孔５５ａを挿通して湾曲部抜け止めピン５５が挿入され、先端構成部材２７に対して第１湾曲駒５７が固定されるようになっている。
【００４９】
（作用）
ａ＞ｂとなっているので、孔５５ａを挿通して穴５５ｂに湾曲部抜け止めピン５５が挿入されると、湾曲部抜け止めピン５５により第１湾曲駒５７が前方へ押され、第１湾曲駒５７前端面が段差５５ｃに押し当てられる。これにより、先端構成部材２７に対する第１湾曲駒のガタツキを防止できる。また、第１湾曲駒５７と先端構成部材２７とで湾曲部抜け止めピン５５が挟み込まれるため、組立の際に湾曲部抜け止めピン５５が容易には抜け落ちず組み立て易い。
【００５０】
（効果）
以上述べた本実施の形態によれば、先端部１８に対する湾曲部１９のガタツキが防止される。また、組立時の湾曲部抜け止めピン５５の脱落が防止され、組立性が向上する。
【００５１】
なお、本発明は、上述の実施の形態のみに限定されるものではなく、発明の要旨を逸脱しない範囲で種々変形実施可能である。
【００５２】
[付記]
（付記項１）
観察対象部位に挿入する細長の挿入部と、
挿入部の先端に位置する先端部の枠体である硬質の先端構成部材と、
前記先端構成部材に組み付けられた前記観察対象部位を撮像するための固体撮像素子と、
前記先端構成部材に組み付けられた前記固体撮像素子から出力される信号を増幅する回路等を構成する電子部品を搭載した回路基板と、
前記回路基板に接続した前記回路基板から出力される信号を前記挿入部内を挿通して手元側まで伝送するケーブルと、を有する内視鏡であって、
前記固体撮像素子及び前記回路基板の周囲を覆い、前記回路基板の後端もしくは前記ケーブルの前端より挿入部長手方向後側に後端が位置するように前記先端構成部材後部に形成されたもしくは前記先端構成部材後部に取り付けられた硬質部材を具備したことを特徴とした内視鏡。
【００５３】
（付記項２）
付記項１に記載の内視鏡であって、
前記硬質部材は前記先端構成部材後部に形成されたものである。
【００５４】
（付記項３）
付記項２に記載の内視鏡であって、
前記先端構成部材の後端面を前記ケーブルの先端より後側に位置させた。
【００５５】
（付記項４）
付記項１ないし付記項３に記載の内視鏡であって、
前記固体撮像素子、及び前記回路基板とケーブルとの接続部を軟性の保護部材で被覆した。
【００５６】
（付記項５）
付記項２ないし付記項４に記載の内視鏡であって、
前記先端構成部材は前記先端部に内蔵される内蔵物を組み付けるための複数の透孔が形成され、
前記透孔のうち前記回路基板が組み付けられる孔の後端面が他の孔の後端面より後方に位置する。
【００５７】
（付記項６）
付記項１ないし付記項５に記載の内視鏡であって、
前記固体撮像素子及び前記回路基板を組み付けるための前記先端構成部材に形成された透孔は前記固体撮像素子及び前記回路基板の略全周を囲むように形成されている。
【００５８】
（付記項７）
付記項２ないし付記項６に記載の内視鏡であって、
前記回路基板を組み付けるための前記先端構成部材に形成された透孔の外壁の一部に、この透孔と先端構成部材の外部とを連通させる切り欠き部を形成した。（付記項８）
付記項１に記載の内視鏡であって、
前記硬質部材は、前記回路基板を組み付けるための前記先端構成部材に形成された透孔の後端に接続された、前記回路基板及び前記固体撮像素子の最大径より大きな内径のパイプであり、このパイプの後端は前記回路基板の後端より後方に位置する。
【００５９】
（付記項９）
付記項５ないし付記項８に記載の内視鏡であって、
前記固体撮像素子、及び前記回路基板と前記ケーブルとの接続部を軟性の保護部材で被覆した。
【００６０】
（付記項１０）
付記項２ないし付記項９に記載の内視鏡であって、
前記固体撮像素子及び前記回路基板及び前記ケーブルと、前記先端構成部材との間の少なくとも一部に弾性部材を設けた。
【００６１】
（付記項１１）
付記項１０に記載の内視鏡であって、
前記回路基板の後端部及び前記ケーブルの前端部と、前記先端構成部材との間にのみ前記弾性部材を設けた。
【００６２】
（付記項１２）
付記項２ないし付記項９に記載の内視鏡であって、
前記固体撮像素子及び前記回路基板及び前記ケーブルと、前記先端構成部材との間の少なくとも一部に硬化後も弾性を有する接着剤を設けた。
【００６３】
（付記項１３）
付記項１２に記載の内視鏡であって、
前記回路基板の後端部及び前記ケーブル前端部と、前記先端構成部材との間にのみ前記接着剤を設けた。
【００６４】
（付記項１４）
内視鏡挿入部の先端部の枠体である先端構成部材と、
前記先端構成部材に形成された透孔に組み付けられたレンズ枠に固定された観察対象部位の像を結像するための観察レンズと、
前記レンズ枠と前記観察対象部位に固定するためのビスやピン等の固定用部材と、
前記先端構成部材に形成された透孔に組み付けられた前記観察用レンズ先端面を洗浄するための流体を噴出する洗浄用ノズルと、
前記洗浄用ノズルが前記先端構成部材から脱落することを防止するためのビスやピン等の第１の抜け止め部材と、
前記先端構成部材前面に取り付けられた先端カバーと、
前記先端カバーが前記先端構成部材から脱落することを防止するためのビスやピン等の第２の抜け止め部材と、を有する内視鏡であって、
前記固定用部材と前記第１の抜け止め部材と前記第２の抜け止め部材のうち少なくとも２つを前記先端構成部材の略同一の径方向で且つ長手方向の異なる位置に配設したことを特徴とした内視鏡。
【００６５】
（付記項１５）
内視鏡挿入部の先端部の枠体である先端構成部材と、
前記先端構成部材に形成された透孔に組み付けられたレンズ枠に固定された観察対象部位の像を結像するための観察レンズと、
前記レンズ枠と前記観察対象部位に固定するためのビスやピン等の固定用部材と、
前記先端構成部材に形成された透孔に組み付けられた前記観察用レンズ先端面を洗浄するための流体を噴出する洗浄用ノズルと、
前記洗浄用ノズルが前記先端構成部材から脱落することを防止するためのビスやピン等の抜け止め部材と、を有する内視鏡であって、
前記固定用部材と前記抜け止め部材を前記先端構成部材の略同一の径方向で且つ長手方向の異なる位置に配設したことを特徴とした内視鏡。
【００６６】
（付記項１６）
付記項１４ないし付記項１５に記載の内視鏡であって、
前記固定部材を前記抜け止め部材より長手方向先端側に位置させた。
【００６７】
（付記項１７）
付記項１４ないし付記項１５に記載の内視鏡であって、
前記内視鏡挿入部の挿入軸を中心として、円周方向に順に、前記観察用レンズと、前記固定部材及び前記抜け止め部材と、前記洗浄用ノズルを配置した。
【００６８】
（付記項１８）
付記項１４ないし付記項１５に記載の内視鏡であって、
前記観察用レンズと前記洗浄用ノズルの前記内視鏡挿入部の挿入軸を中心とした円周方向の略中間位置に前記固定部材及び前記抜け止め部材を配置した。
【００６９】
（付記項１９）
観察対象部位に挿入する細長の挿入部と、
前記挿入部の先端部を構成する枠体である先端構成部材と、
照明光を導光するための前記挿入部内を挿通するライトガイドと、
前記ライトガイドの出射端からの出射光を観察対象部位に向けて配光する照明用レンズと、
前記照明用レンズを保持するための前記先端構成部材に組み付けられる略円筒状のレンズ枠と、を有する内視鏡であって、
前記レンズ枠の外周の一部に前記先端構成部材に対する前記レンズ枠の相対的な位置決めをするための鍔状の突起を形成したことを特徴とする内視鏡。
【００７０】
（付記項２０）
付記項１９に記載の内視鏡であって、
前記突起は、その径が前記レンズ枠の外周より大きく、その外周が前記レンズ枠と同軸の円弧である。
【００７１】
（付記項１４ないし付記項１８に係る従来の技術）
従来の内視鏡では、例えば実公平６−４２６４２の図２で示されるように、先端カバーの抜け止め部材、観察用レンズの固定用部材、及び洗浄用ノズルの抜け止め部材とが、内視鏡挿入軸に垂直な断面において、同一平面上に配されていた。
【００７２】
（付記項１４ないし付記項１８に係る発明が解決しようとする課題）
従来は、実公平６−４２６４２で示されるように、先端カバーの抜け止め部材、観察用レンズの固定用部材及び洗浄用ノズルの抜け止め部材を、内視鏡挿入軸に垂直な断面において同一平面上に配置するスペースを確保していた。内視鏡の細径化に伴い、各内蔵物を小さくし、なおかつ各内蔵物間を狭めていくと、前記の固定用部材や抜け止め部材の配置スペースを確保する目的で、内視鏡の先端外径を大きくする必要が出てきてしまった。
【００７３】
付記項１４ないし付記項１８の目的は、各固定用部材のスペースを確保したまま、内視鏡先端部の径を細くすることである。
【００７４】
（付記項１４ないし付記項１８に係る手段の補足）
洗浄用ノズルと観察用レンズとは、洗浄用ノズルによる視野ケラレを防ぐため、ある距離以上近づけることができず、両者の間には必ずスペースができる。このスペースに観察用レンズの固定用部材、洗浄用ノズル抜け止め部材、及び先端カバー抜け止め部材のうちの少なくとも２つを、内視鏡挿入軸方向に垂直な断面において非同一面上で、かつ内視鏡挿入軸に平行な同軸上に配することにより、円周上の別の位置に前記固定用部材及び抜け止め部材を配置するための新たなスペースを確保する必要が無くなり、内視鏡先端部の径を小さくできる。
【００７５】
（付記項１４ないし付記項１８に係る効果の補足）
洗浄用ノズルと観察用レンズとは、視野ケラレを防ぐため、ある距離以上近づけることができず、両者の間にはスペースができる。このスペースにノズル抜け止め部材、先端カバー抜け止め部材及び観察用レンズ固定用部材のうち少なくとも２つを内視鏡挿入軸に垂直な断面において非同一平面上で、かつ内視鏡挿入軸に平行な同軸上に配することにより、前記ノズル抜け止め部材、先端カバー抜け止め部材及び観察用レンズ固定用部材を配するスペースを新たに先端構成部材に確保する必要がなく、内視鏡先端部を細径化できる。
【００７６】
（付記項１９及び付記項２０に係る従来の技術）
従来は、照明用レンズのレンズ枠の先端側において、略全周に径方向に突出したフランジ部と呼ばれる鍔部を形成し、該鍔部を前方より先端構成部材に突き当てることにより、照明用レンズ先端面と内視鏡先端部との相対位置を決めていた。例えば、特開平１０−０２８６６９では、図２の中で、先端構成部材と突き当てるために全周に渡って形成された前記レンズ枠鍔部に一部切り欠いた凹部を形成し、レンズ枠を先端構成部材から取り外す際の治具を引っかけやすくしていた。
【００７７】
（付記項１９及び付記項２０に係る発明が解決しようとする課題）
照明用レンズを固定するパイプ状のレンズ枠の外周の全周に、前記レンズ枠の外周よりも径の大きな外径を有す鍔部を形成していたので、内視鏡先端部を構成する先端構成部材及びその先端に取り付けられる先端カバーに、前記レンズ枠を内嵌するための孔の径を前記鍔部が収まるよう、全周に渡って大きくする必要があり、そのため、他内蔵物と前記照明用レンズとの間の先端カバー肉厚が薄くなってしまい、破損しやすかった。また、前記肉厚を大きくするために、先端カバーの外径を大きくしなくてはならなかった。
【００７８】
付記項１９及び付記項２０の目的は、内視鏡先端部の外径を大きくすることなく、先端カバーの破損を防止することである。
【００７９】
（付記項１９及び付記項２０に係る手段の補足）
照明用レンズを固定するレンズ枠の外周上に一部だけ突出した鍔部を形成することにより、レンズ枠を挿入するための先端カバーの孔の径を前記レンズ枠の形状に合わせて、一部だけ大きくした異形孔とでき、そのため、前記先端カバー上の孔の大きさを小さくでき、先端部外径を大きくすること無く、前記照明用レンズと他内蔵物との間の先端カバー肉厚を大きくでき、前記先端カバーの破損を防止できる。
【００８０】
（付記項１９及び付記項２０に係る効果の補足）
照明用レンズのレンズ枠の先端側に設けられた先端構成部材との位置出し用の鍔部を全周ではなく、一部にのみ形成することにより、前記レンズ枠が挿入される先端カバー上の孔は前記鍔部が挿入できるように一部にのみ太径部を持った異径孔として、前記レンズ枠が全周に渡って鍔部を有する際に必要な孔の径より小さい径とすることができる。そのため、先端カバー上で各内蔵物が挿入される孔間の距離を大きくとって肉厚を確保でき、内視鏡先端外径を大きくすることなく、先端カバーの破損を防止できる。
【００８１】
【発明の効果】
以上説明したように本発明によれば、観察対象部位に挿入する細長の挿入部と、挿入部の先端に位置する先端部の枠体である硬質の先端構成部材と、前記先端構成部材に組み付けられた前記観察対象部位を撮像するための固体撮像素子と、前記先端構成部材に組み付けられた前記固体撮像素子から出力される信号を増幅する回路等を構成する電子部品を搭載した回路基板と、前記回路基板に接続した前記回路基板から出力される信号を前記挿入部内を挿通して手元側まで伝送するケーブルとを有する内視鏡であって、固体撮像素子及び前記回路基板の周囲を覆い、前記回路基板の後端もしくは前記ケーブルの前端より挿入部長手方向後側に後端が位置するように前記先端構成部材後部に形成されたもしくは前記先端構成部材後部に取り付けられた硬質部材を具備したことにより、前記固体撮像素子及び前記回路基板の周囲のみ前記硬質部材で覆い、前記先端構成部材全体が後方に延びることを抑え、先端部の硬質部分が大きくなることを抑えつつ、固体撮像素子及び回路基板の破損を防止できる。
【図面の簡単な説明】
【図１】図１ないし図６は本発明の第１の実施の形態に係り、図１は内視鏡装置の全体構成を示す説明図
【図２】先端部及び湾曲部前端側の構成を示す断面図
【図３】図２のＡ−Ａ断面図
【図４】図３のｄ１−ｄ２−ｄ３−ｄ４−ｄ５断面図
【図５】図２のＢ−Ｂ断面図
【図６】図３のｅ−ｅ断面図
【図７】本発明の第２の実施の形態に係り、先端部の構成を示す断面図
【図８】図８ないし図１０は本発明の第３の実施の形態に係り、図８は先端部の構成を示す断面図
【図９】図８のＢ−Ｂ断面図
【図１０】図８のＣ−Ｃ断面図
【図１１】図１１ないし図１２は本発明の第４の実施の形態に係り、図１１は先端部を前方から見た図
【図１２】図１１のＣ−Ｃ断面図
【図１３】本発明の第５の実施の形態に係り、図１１の矢印方向から洗浄用ノズルの開口部を拡大して見た図
【図１４】図１４ないし図１５は本発明の第６の実施の形態に係り、図１４は先端構成部材と湾曲部との接続部分の構造を示す断面図
【図１５】図１４を拡大して示した断面図
【符号の説明】
１…内視鏡装置
２…内視鏡
３…光源装置
４…ビデオプロセッサ
５…モニタ装置
６…ＶＴＲデッキ
７…ビデオディスク
８…ビデオプリンタ
１１…ライトガイド
１２…可撓管部
１３…操作部
１４…ユニバーサルコード
１５…ライトガイドコネクタ
１６…信号ケーブル
１７…信号コネクタ
１８…先端部
１９…湾曲部
２０ａ…鉗子挿入口
２０ｂ…送気・送水口
２１…観察用レンズ
２２…固体撮像素子
２３…洗浄用ノズル
２４…鉗子チャンネル
２５…照明用レンズ
２６…レンズ枠
２７…先端構成部材
２８…先端カバー
２９…回路基板
３０…ケーブル
３５ａ…固体撮像素子用透孔
３５ｂ…ライトガイド用透孔
３５ｃ…送気・送水用透孔
３５ｄ…鉗子チャンネル用透孔
４２…ケーブル前端
４１ａ…（固体撮像素子用透孔の）後端面
４１ｂ…（ライトガイド用透孔の）後端面
４１ｃ…（送気・送水用透孔の）後端面
４１ｄ…（鉗子チャンネル用透孔の）後端面
５７…第１湾曲駒
６０…第１関節
１０１…挿入部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope, and more particularly, to a so-called electronic endoscope having a solid-state image sensor for imaging an observation target at a hard tip.
[0002]
[Prior art]
In recent years, by inserting an elongated insertion portion into a body cavity, an inspection target site in the body cavity can be observed without requiring an incision, and treatment can be performed in a treatment instrument channel of an endoscope as necessary. Endoscopes that can be used for various treatments and treatments by inserting tools are widely used.
[0003]
An electronic endoscope, which is a kind of such an endoscope, includes an observation lens that forms an image of a site to be observed at the distal end of an insertion portion, a solid-state imaging device for capturing the formed image, and the like. A circuit board constituting an imaging means, a circuit for amplifying an imaging signal output from the solid-state imaging device, a front end portion of a cable for transmitting the amplified imaging signal and the like to the hand side of the endoscope, and the like The imaging signal transmitted to the hand side is converted into an image signal that can be displayed on a monitor by a video processor that is an external device, and an observation image is displayed on the monitor device. In addition, a bending portion that can be bent by an operation from the hand side is generally connected to the proximal end side of the distal end portion of the endoscope having a flexible insertion portion, and the distal end portion can be oriented in a desired direction. It can be done.
[0004]
An example of this type of conventional endoscope is shown in FIG. 4 of JP-A-7-31582. In this example, an observation lens, a fixed imaging device, and a circuit board are inserted and fixed in a through hole formed in a rigid distal end constituent member that is a frame body of the distal end portion of the endoscope. The cable extends to the rear. At this time, the rear end of the tip constituent member is positioned in front of the front end of the cable, and a part of the circuit board and the periphery of the connection portion between the circuit board and the cable are exposed rearward from the tip constituent member. ing.
[0005]
Another example is JP-A-8-56896. In this example, a part of the circuit board and the front end of the cable are exposed rearward from the rear end of the tip component member, and the circuit board extends from the front end of the cable. Covered with an elastic covering member, the force applied between the cable and the circuit board is reduced, and the disconnection between the cable and the circuit board is prevented.
[0006]
[Problems to be solved by the invention]
However, in the conventional configuration as described in JP-A-7-31582, the rear end surface of the hard tip constituent member is positioned forward in the longitudinal direction rather than the solid-state imaging device or the circuit board. When the curved portions to be continuously provided were bent, a large bending force was applied to the solid-state imaging device and the circuit board, and this portion was easily damaged. Therefore, if all the rear end surfaces of the tip component members are extended so as to be positioned behind the circuit board so as to protect the solid-state imaging device and the circuit board, the hard tip component member becomes large, and the hard The request to miniaturize the tip could not be met. Further, as described in JP-A-8-56896, when the circuit board is covered with the elastic member from the circuit board and protected, the cable / circuit board can be prevented from being disconnected. The bending force applied to the circuit board and the solid-state imaging device cannot be sufficiently reduced due to the curvature of, and these remain easily damaged.
[0007]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an endoscope that can prevent damage to the solid-state imaging device and the circuit board while suppressing an increase in the hard portion of the tip.
[0008]
[Means for Solving the Problems]
To achieve the above object, a first endoscope of the present invention includes an insertion portion that can be inserted into a subject, and a distal end configuration that forms a distal end side of the insertion portion and is formed in a substantially cylindrical shape from a hard material. A member, a first hole portion that is provided in the tip component member, and that houses an image pickup unit including an image pickup element, a circuit board electrically connected to the image pickup element, and a cable connected to the circuit board; Arranged on the base end side of the component,Behind the circuit boardA first rear end surface in which an opening of the first hole is provided; a second hole for disposing a built-in object that is provided in the tip constituent member and passes through the insertion portion; and the tip constituent memberofAnd a second rear end surface disposed on the front end side with respect to the first rear end surface provided on the base end side and provided with the opening of the second hole.
The second endoscope of the present invention includes an insertion portion that can be inserted into a subject, a distal end constituent member that forms a distal end side of the insertion portion and is formed in a substantially cylindrical shape with a hard material, and the distal end constituent member A first hole for housing an imaging unit comprising an imaging element, a circuit board electrically connected to the imaging element, and a cable connected to the circuit board; and a proximal end side of the distal end component member A first rear end surface that is disposed and provided with an opening of the first hole portion on the rear side of the circuit board, and a forceps channel that is provided on the distal end component member and passes through the insertion portion. A second rear portion disposed on the distal end side with respect to the first rear end surface disposed on the proximal end side of the second hole portion and the distal end component member and provided with the opening of the second hole portion. And an end face.
The third endoscope of the present invention includes an insertion portion that can be inserted into a subject, a distal end constituent member that forms a distal end side of the insertion portion and is formed in a substantially cylindrical shape with a hard material, and the distal end constituent member A first hole for housing an imaging unit comprising an imaging element, a circuit board electrically connected to the imaging element, and a cable connected to the circuit board; and a proximal end side of the distal end component member A first rear end surface that is disposed and provided with an opening of the first hole on the rear side of the circuit board; and a light guide that is provided in the distal end component member and is inserted through the insertion portion. A second rear portion disposed on the distal end side with respect to the first rear end surface disposed on the proximal end side of the second hole portion and the distal end component member and provided with the opening of the second hole portion. And an end face.
The fourth endoscope of the present invention includes an insertion portion that can be inserted into a subject, a distal end constituent member that forms a distal end side of the insertion portion and is formed in a substantially cylindrical shape with a hard material, and the distal end constituent member A first hole for housing an imaging unit comprising an imaging element, a circuit board electrically connected to the imaging element, and a cable connected to the circuit board; and a proximal end side of the distal end component member A first rear end surface that is disposed and provided with an opening of the first hole on the rear side of the circuit board, and an air / water supply conduit that is provided in the tip component member and passes through the insertion portion 2nd hole part for arrange | positioning a pipe, It arrange | positions in the front end side with respect to the said 1st rear end surface which is arrange | positioned at the base end side of the said front-end | tip component member, and the opening part of the said 2nd hole part is provided. And a second rear end face formed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
1 to 6 relate to the first embodiment of the present invention, FIG. 1 is an explanatory view showing the overall configuration of the endoscope apparatus, and FIG. 2 is a cross-sectional view showing the configuration of the front end portion and the bending portion front end side, 3 is a sectional view taken along line AA in FIG. 2, FIG. 4 is a sectional view taken along line d1-d2-d3-d4-d5 in FIG. 3, FIG. 5 is a sectional view taken along line BB in FIG. FIG.
[0010]
(Constitution)
In FIG. 1, the structure of the endoscope apparatus 1 comprised including the endoscope 2 of this Embodiment is shown.
The endoscope 2 includes an operation unit 13 for an operator to hold and operate the endoscope 2, and an insertion unit 101 that is connected to the distal end side of the operation unit 13 and is inserted into an observation target site such as a body cavity. A universal cord 14 that extends from the side of the operation unit 13 and connects to an external device, and a light source device 3 that is provided at an end portion of the universal cord 14 and emits illumination light that illuminates an observation target site, is detachably connected. And a video processor 4 for performing signal processing (described later) on an imaging signal from a solid-state imaging device (described later) provided from the side of the light guide connector 15 and provided at the distal end of the insertion portion. It is mainly composed of a signal cable 16 having a signal connector 17 at its end.
[0011]
The insertion portion 101 includes a flexible elongated flexible tube portion 12 continuously provided at the distal end of the operation portion 13, a bendable bending portion 19 continuously provided at the distal end of the flexible tube portion 12, and the curved portion. It is comprised from the front-end | tip part 18 connected with the front-end | tip of the part 19. FIG.
[0012]
In the endoscope 2, a light guide 11 for guiding illumination light inserted through the insertion portion 101, the operation portion 13, the universal cord 14, and the light guide connector 15 is provided. The light incident end of the light guide 11 is attached to the light guide connector 15, and the illumination light emitted from the light source lamp 9 provided in the light source device 3 and condensed by the condenser lens 10 is reflected on the light guide 11. It is incident on the light incident end. The illumination light is guided by the light guide 11 and emitted from the light emitting end of the light guide 11 attached to the tip portion 18 to illuminate the observation target part.
[0013]
The observation image by the reflected light from the observation target site illuminated with the illumination light is imaged by a solid-state imaging device 22 (not shown) provided at the tip 18, and an imaging signal output from the solid-state imaging device 22 is The signal is transmitted to the video processor 4 through a cable 30 (not shown here) that passes through the insertion portion 101, the operation portion 13, the universal cord 14, the light guide connector 15, the signal cable 16, and the signal connector 17. .
[0014]
The video processor 4 performs signal processing for converting the image signal from the solid-state image sensor 22 into an image signal that can be displayed on the monitor, and outputs the image signal to the monitor device 5. Thereby, the monitor apparatus 5 displays the observation image imaged with the solid-state image sensor 22. FIG. The video processor 4 is connected to a VTR deck 6 and a video disk 7 for recording an observation image, and a video printer 8 for printing the observation image. The imaging signal is converted into an image signal for output to these devices.
[0015]
When the insertion portion 101 is inserted into, for example, a body cavity to observe an observation target, the exposure of an optical system provided in front of the light guide 11 light emitting end in the tip portion 18 or in front of the solid-state imaging device 22 is performed. For example, body fluid or the like adheres to the portion, and the amount of illumination light decreases or the observation image becomes invisible. Therefore, the endoscope 2 has a function of cleaning the exposed surface of the optical system. An air / water supply port 20b for connecting an air / water supply pump (not shown) is provided on the side of the operation unit 13, and the air / water supply port 20b is provided inside the operation unit 13 and the insertion unit 101. This is communicated with a cleaning nozzle 23 (not shown) protruding from the tip 18 through an air / water supply tube 48 (not shown) to be inserted, and air and water are exposed from the cleaning nozzle 23 to the exposed surface of the optical system. The exposed surface of the optical system can be cleaned.
[0016]
The endoscope 2 not only obtains an observation image of an observation target part, but also can collect and treat a biological tissue in the body cavity, which is the observation target part, for example. A forceps insertion port 20a for inserting a treatment tool such as a forceps (not shown) for performing a treatment on the observation target site is provided on the side of the operation unit 13, and the treatment tool inserted from the forceps insertion port 20a. Is inserted through the forceps channel 24 (not shown) that is inserted through the operation unit 13 and the insertion unit 101 and protrudes from the distal end portion 18, thereby allowing treatment to be performed on the site to be observed.
[0017]
The configuration of the distal end portion 18 and the distal end portion of the bending portion 19 which are characteristic of the endoscope 2 of the present embodiment will be described with reference to FIG.
The frame of the distal end portion 18 is composed of a distal end constituting member 27 made of metal and formed in a substantially cylindrical shape. The distal end component member 27 is formed with a plurality of through holes in the longitudinal direction for accommodating the built-in material of the distal end portion 18.
A bending portion 19 is continuously provided on the proximal end side of the distal end portion 18. The bending portion 19 has a plurality of bending pieces connected to each other by pins or the like so as to be rotatable. The first bending piece 57 on the most distal side and the second bending piece 58 that follows are connected by a bending pin 59 to form a first joint 60. The following joints have the same configuration. At the distal end of the bending portion 19, a bending wire 61 that passes through the operation portion 13, the flexible tube portion 12, and the bending portion 19 extends from a bending operation lever (not shown) of the operation portion 13. The distal end of the bending wire 61 is fixed to a substantially cylindrical bending wire fixing member 19c attached to a position closer to the front end than the first joint 60 on the inner periphery of the first bending piece 57. Accordingly, the bending portion 19 can be bent by pulling the bending wire 61 with the bending operation lever of the operation portion 13.
The first bending piece 57 is formed to be long forward, and this portion is fitted onto the outer periphery of the rear end of the tip constituent member 27 so that the tip constituent member 27 and the first bending piece 57 are integrally attached. Yes. That is, by pulling the bending wire 61, the distal end portion 18 can be directed in a desired direction.
The outer periphery of the bending pieces such as the first bending piece 57, the second bending piece 58,... Is covered with a metal mesh tube 19a. The first bending piece 57 is fixed to the outer periphery.
The outer periphery of the front end of the tip component member 27 is covered with a tip cover 28 formed of an insulating material. The outer periphery of the distal end portion 18 and the bending portion 19 from the rear end of the distal end cover 28 is covered with a covering member 12b formed of rubber or the like, and the distal end of the covering member 12b is configured with a binding thread or an adhesive, for example. The member 27 is fixed to the outer periphery.
A through hole is formed in the tip cover 28 at a position corresponding to the through hole of the tip constituent member 27.
[0018]
The configuration of the through hole for accommodating the built-in tip portion 18 formed in the tip constituent member 27 will be described with reference to FIGS. 2, 4, and 6.
As shown in FIG. 2, the tip component member 27 has a light guide through hole 35 b for housing the light guide 11 and an optical system related thereto, a solid-state imaging device 22, and a solid body for housing the members related thereto. An imaging element through-hole 35a is formed. Further, as shown in FIG. 4, the tip component member 27 is formed with an air / water feed through hole 35 c for attaching members related to the air / water feed tube 48 and the cleaning nozzle 23. As shown in FIG. 6, a forceps channel through-hole 35 d that forms the tip of the forceps channel 24 is formed in the tip component member 27.
[0019]
Next, the configuration of members and the like housed in the solid-state image sensor through-hole 35a will be described.
As shown in FIG. 2, a lens frame 32 in which a plurality of observation lenses 21 are assembled on the inner periphery is attached to the tip of the through hole 35a for the solid-state imaging device.
The solid-state image sensor through-hole 35a behind the lens frame 32 is formed with a large diameter, and the solid-state image sensor 22 is attached to the rear end of the lens frame 32.
Behind the solid-state image pickup device 22 is disposed a circuit board 29 on which electronic components constituting a signal amplification circuit and the like are connected in lead connection to the solid-state image pickup device 22.
A cable 30 for transmitting an image pickup signal to the video processor 4 extends from the circuit board 29, and this cable 30 passes through the insertion portion 101, the operation portion 13, the universal cord 14, the light guide connector 15, and the signal cable 16. The signal connector 17 is connected.
As shown in FIG. 3, the cable 30 is configured by bundling several of the plurality of small cables 33 and covering them with a resin tube 34. A small cable 33 such as a power cable or a ground cable that is not covered by the resin tube 34 is also connected to the signal connector 17 in parallel with the cable 30.
A heat shrinkable tube 31 is provided in a range from the vicinity of the rear end of the lens frame 32 to the vicinity of the front end of the cable 30 so as to cover the solid-state imaging device 22 and the circuit board 29.
[0020]
In the solid-state imaging element through-hole 35a and the peripheral portion thereof, the rear end surface 41a of the distal end component member 27 is formed to be located rearward of the cable front end 42 that is the front end of the resin tube 34 of the cable 30.
Further, an elastic member 56 such as RTV silicone rubber is filled in a gap between the solid-state imaging element through-hole 35 a and the heat-shrinkable tube 31 or the cable 30. The elastic member 56 may be an elastic adhesive even after curing.
[0021]
Next, the configuration of the light guide through hole 35b will be described.
As shown in FIG. 2, a lens frame 26 having an illumination lens for distributing the illumination light emitted from the light guide 11 is fitted to the tip of the light guide through hole 35b. Yes. At the rear end of the lens frame 26, the end portion of the light guide 11 is fitted.
At the position where the light guide through hole 35b is formed, the rear end of the leading end component member 27 is a rear end face 41b.
[0022]
Next, the structure of the air / water feed through hole 35c will be described.
As shown in FIG. 4, the tip of the air / water feeding through hole 35c is formed with a large diameter, and the cleaning nozzle 23 is fitted in this portion. The exit of the cleaning nozzle 23 is bent by approximately 90 degrees from the air / water feed through hole 35c, and is emitted toward the surface of the optical system exposed from the tip 18 such as the illumination lens 25. ing.
A pipe pipe 47 for connecting an air / water feed tube 48 is fitted to the rear end of the air / water feed through hole 35c, and an air / water feed pipe is connected to the rear end of the pipe pipe 47. The tube 48 is fitted. The pipe pipe 47 is bent in the middle, and has a shape that avoids interference between the pipe pipe 47 and other built-in objects on the rear side of the tip constituting member 27.
Further, a counterbore hole 49 is formed at the rear end of the air / water feed through hole 35c, and a bottom surface of the counterbore hole 49 serves as a rear end face 41c of the air / water feed through hole 35c. . In this counterbore hole 49, a bent portion at the rear of the pipe pipe 47 is located. By forming the counterbore 49, the pipe pipe 47 can be positioned on the front side. Since the pipe pipe 47 can be positioned on the front side, the front end of the air / water supply tube 48 can be arranged at a position away from the first joint 60 of the bending portion 19, and the pipe line is bent when the bending portion 19 is bent. Even if the air / water supply tube 48 connected to the rear end of the pipe 47 is bent, the radius of curvature increases, so the burden on the air / water supply tube 48 is reduced and the resistance is improved.
As shown in FIG. 5, a nozzle retaining pin 39 made of an insulating material for fixing the cleaning nozzle 23 is inserted into a lateral hole communicating with the tip cover 28 and the tip component member 27. The rear end of the nozzle retaining pin 39 is a flat surface, and the side surface of the tip cover 28 at a position corresponding to the nozzle retaining pin 39 is also a flat surface. It is on the same side. Since the rear end of the nozzle retaining pin 39 is flat, there is an advantage that the nozzle retaining pin 39 can be easily processed.
[0023]
Next, the configuration of the forceps channel through hole 35d will be described.
As shown in FIG. 6, a connection tube 24a for connecting a channel tube 24b constituting the forceps channel 24 is fitted forward from the rear end surface 41d of the forceps channel through-hole 35d. A channel tube 24b is fitted to the rear end. The outer periphery of the channel tube 24b is covered with a spiral tube 24c made of metal, and ensures strength against a treatment instrument inserted inside.
Behind the rear end surface 41d of the forceps channel through-hole 35d, there is a gap between the distal end component member 27 or the front side portion of the first bending piece 57 that is externally fitted to the distal end component member 27 and the channel tube 24b that is externally fitted to the connecting tube 24a. An elastic member 56 made of viscous RTV silicone rubber or the like is disposed. This prevents the channel tube 24b from coming off, absorbs the bending force applied to the channel tube 24a when the bending portion 19 is bent, and improves the resistance of the channel tube 24a constituting the forceps channel 24.
[0024]
Next, the longitudinal lengths of the rear end surfaces 41a, 41b, 41c, and 41d of the solid-state imaging element through-hole 35a, the light guide through-hole 35b, the air / water feeding through-hole 35c, and the forceps channel through-hole 35d described above, respectively. The positional relationship of directions will be described.
The rear end surface of the distal end component member 27 is the rear end surface 41d of the forceps channel through hole 35d, the rear end surface 41c of the air / water supply through hole 35c, the rear end surface 41b of the light guide through hole 35b, and the solid-state imaging device. It forms so that it may become the order of the rear-end surface 41a of the through-hole 35a for use.
The rear end surfaces 41 a, 41 b, 41 c, 41 d of the distal end component member 27 are positioned as far forward as possible from the requirement for shortening the rigid distal end portion 18 and the requirement for improving the resistance of the built-in object when the bending portion 19 is curved. However, the rear end surface 41 a of the solid-state image sensor through hole 35 a is positioned behind the circuit board 29 in order to protect the solid-state image sensor 22 and the circuit board 29. Since the observation lens 21, the solid-state imaging device 22, the circuit board 29, and the connection part of the circuit board 29 and the cable 30 are arranged long in the longitudinal direction of the front end part 18, the rear end face 41 a is formed rearward, for example, FIG. In the position of the cross section shown in FIG. 3, the tip constituting member 27 exists only around the solid-state imaging element through-hole 35a, and no other through-hole exists. Thereby, damage to the solid-state imaging device 22 and the circuit board 29 when the bending portion 19 is bent is prevented.
Similarly, the position of the rear end surface of each through hole is different depending on the built-in material accommodated in each through hole. Thereby, the length of the tip constituting member 27 is shortened while preventing damage to each built-in part of the tip portion 18 when the bending portion 19 is bent.
[0025]
Next, the positional relationship in the radial direction between the solid-state imaging element through hole 35a and the forceps channel 24 will be described.
As shown in FIG. 2, the solid-state image sensor through-hole 35a is formed to be slightly larger than the solid-state image sensor 22 at the position where the solid-state image sensor 22 is accommodated. There is a gap between them. As shown in FIG. 3, the gap t <b> 1 formed on the opposite side is larger than the gap t <b> 2 on the side where the forceps channel 24 is located, as viewed from the center of the solid-state imaging device 22. The forceps channel 24 does not have a uniform outer diameter in the endoscope insertion direction, but has a maximum outer diameter portion with a large diameter in part. Therefore, when assembling the solid-state imaging device 22 to the tip component member 27, the maximum outer diameter portion of the forceps channel 24 is passed through the gap opposite to the forceps channel 24 while the solid-state imaging device 22 escapes, and then the forceps channel Assembling can be performed even if the distance between the forceps channel 24 and the solid-state image sensor 22 is reduced by bringing the solid-state image sensor 22 to the 24 side. Generally, it is desirable that the tip portion 18 and the like be as thin as possible, and the tip portion 18 can be further reduced in diameter by forming a small gap between the solid-state imaging element through-hole 35a and the forceps channel 24.
[0026]
(Function)
The operation of this embodiment will be described.
Since the rear end surface 41a of the solid-state image sensor through hole 35a of the front-end component 27 is formed to extend to the rear end side from the cable front end 42, the periphery of the solid-state image sensor 22 and the circuit board 29 is a hard metal. It is covered with the tip constituting member 27 formed by If the periphery of the solid-state imaging device 22 and the circuit board 29 is not covered with the tip component member 27, the solid-state imaging device 22 and the circuit board 29 are only covered with the heat-shrinkable tube 31. It becomes weak to the bending force applied to the direction perpendicular to the insertion axis when the portion 19 is bent. However, in the present embodiment, since the structure is covered with the tip component member 27 while ensuring a slight gap, the tip component member 27 absorbs the bending force and prevents the solid-state imaging device 22 and the circuit board 29 from being damaged. it can. Further, in general, each built-in object of the insertion portion 101 has its distal end fixed to the distal end component member 27, and a portion disposed at a position behind the distal end component member 27 of the built-in object is a request to bend the bending portion 19. It is comprised so that it may have softness. At this time, if the distance between the rear end surface of the distal end component member 27 and the first joint 60 of the bending portion 19 is short, the soft portion of each built-in object in front of the first joint 60 is short. However, since it is bent suddenly by the first joint 60, the resistance becomes low. In order to avoid this, when the first joint 60 is moved rearward and the distance between the rear end surface of the distal end component member 27 and the first joint 60 is increased, the hard distal end portion 18 becomes longer. However, in the present embodiment, only the rear end surface 41a of the solid-state image pickup element through-hole 35a in which the solid-state image pickup element 22 and the circuit board 29 are accommodated extends rearward, and the rear end component member 27 on which other built-in objects are located. Since the end faces 41b, 41c, and 41d are left in the front as they are, the solid imaging element 22 and the circuit board 29 are prevented from being damaged while suppressing the length of the hard tip 18 from being increased.
[0027]
(effect)
According to this embodiment described above, the following effects can be obtained.
The elongated insertion portion 101 to be inserted into the observation target site, the rigid distal end constituting member 27 that is a frame of the distal end portion 18 located at the distal end of the flexible tube portion 12, and the observation assembled to the distal end constituting member 27 A solid-state imaging device 22 for imaging a target portion; a circuit board 29 on which electronic components constituting a circuit and the like for amplifying a signal output from the solid-state imaging device 22 assembled to the tip component member 27; An endoscope 2 having a cable 30 for transmitting a signal output from the circuit board 29 connected to the circuit board 29 to the hand side through the insertion portion 101, the solid-state imaging device 22 And the rear end of the circuit board 29 so that the rear end of the rear end of the circuit board 29 or the front end of the cable 30 is located on the rear side in the longitudinal direction of the insertion portion. Since the hard member formed on or attached to the rear part of the tip component member 27 is covered with the hard member only around the solid-state imaging device 22 and the circuit board 29, the tip component member 27 as a whole is covered. It is possible to prevent the solid-state imaging device 22 and the circuit board 29 from being damaged while suppressing the rearward extension and suppressing the hard portion of the distal end portion 18 from increasing.
[0028]
(Second Embodiment)
FIG. 7 relates to the second embodiment of the present invention and is a cross-sectional view showing the configuration of the tip portion. In addition, the structure of the site | part which is not described in this Embodiment is a structure similar to 1st Embodiment.
[0029]
(Constitution)
As shown in FIG. 7, the observation lens 21, the solid-state imaging device 22, the circuit board 29, and the cable 30 are assembled from the distal end side to the solid-state imaging element through-hole 35 a of the distal-end component member 27. Are arranged so as to protrude rearward from the rear end face 41a of the solid-state imaging element through-hole 35a. The rear end surface 41a of the solid-state imaging element through-hole 35a may be formed, for example, so as to be in the same position in the longitudinal direction as the rear end surface 41b of the light guide through-hole 35b. Further, the rear end face 41a may be formed at a position forward of the circuit board 29 and behind the circuit board 29 as shown in the drawing.
A metal pipe 36 is fitted to the rear end of the solid-state imaging element through hole 35a, and the rear end of the pipe 36 is assembled so as to be located behind the cable front end 42. Note that the gap between the pipe 36 and the cable 30 may be filled with the elastic member 56 as in the first embodiment.
[0030]
(Function)
The operation of this embodiment will be described.
When the bending portion 19 is bent, a force in the bending direction is applied in a direction substantially orthogonal to the insertion direction. Part of the solid image pickup element 22, the circuit board 29, and a part of the front end of the cable 30 is covered with a hard metal pipe 36, and a slight gap is secured between the pipe 36 and the built-in object. The force in the bending direction applied to the image sensor 22 and the circuit board 29 is reduced by the metal pipe 36, and the solid-state image sensor 22 and the circuit board 29 can be prevented from being damaged.
[0031]
(effect)
According to the present embodiment described above, the bending force applied to the solid-state imaging device 22 and the circuit board 29 when the bending portion 19 is bent is changed to the metal pipe 36 instead of the tip component member 27 of the first embodiment. Therefore, damage to the solid-state imaging device 22 and the circuit board 29 can be prevented, and as a result, the same effect as in the first embodiment can be obtained.
[0032]
In addition, when the observation lens 21, the solid-state imaging device 22, and the circuit board 29 are rearranged to those having different lengths in the longitudinal direction, only the pipe 36 has a different length by using the same tip component member 27. This can be dealt with only by recombination, and the flexibility regarding the dimensions of the built-in observation lens 21, solid-state imaging device 22, and circuit board 29 is improved.
[0033]
(Third embodiment)
8 to 10 relate to a third embodiment of the present invention, FIG. 8 is a cross-sectional view showing the structure of the tip, FIG. 9 is a cross-sectional view along BB in FIG. 8, and FIG. It is C sectional drawing. In addition, the structure of the site | part which is not described in this Embodiment is a structure similar to 1st Embodiment.
[0034]
(Constitution)
As shown in FIG. 8, the distal end component member 27, which is a frame of the distal end portion 18, has through holes such as a solid-state imaging element through hole 35a, a light guide through hole 35b, and an air / water feed through hole 35c. Is formed. A tip cover 28 is fitted to the tip of the tip constituent member 27, and through holes are formed in the tip cover 28 corresponding to the positions of the respective through holes formed in the tip constituent member 27.
A lens frame 32, a solid-state image sensor 22, a circuit board 29, and a cable 30 that fix the observation lens 21 from the front end side are assembled in the solid-state image sensor through hole 35a.
The illumination lens 25 and the distal end portion of the light guide 11 are assembled in the light guide through hole 35b from the distal end side.
A cleaning nozzle 23 is attached to the air supply / water supply through hole 35c so as to protrude from the front end surface of the front end portion 18, and an air supply / water supply tube 48 is assembled to the rear end side via a pipe pipe 47. It has been.
[0035]
As shown in FIG. 9, by inserting a tip cover retaining pin 38 into a groove formed in the outer periphery of the tip component member 27 and a hole formed in the tip cover 28 communicating with the groove, the tip of the tip cover 28 is inserted. Omission from the component member 27 is prevented.
The lens frame 32 of the observation lens 21 is fixed to the tip constituent member 27 by tightening a screw 37 to a screw portion formed on the tip constituent member 27. The screw 37 is located at the periphery of the tip constituting member 27 between the solid-state image sensor through-hole 35a and the air / water-feeding through-hole 35c.
As shown in FIGS. 8 and 10, a concave groove 39a is formed on the outer periphery of the cleaning nozzle 23 in the cross section shown in FIG. 10, and a tip component member 27 formed at a position corresponding to the groove 39a. Since the nozzle retaining pin 39 is abutted through this hole and the hole of the tip cover, the cleaning nozzle 23 is prevented from falling off. The nozzle retaining pin 39 is located at the periphery of the tip constituting member 27 between the solid-state imaging element through-hole 35a and the air / water-feeding through-hole 35c.
When FIG. 9 and FIG. 10 are overlapped, the screw 37 in FIG. 9 and the nozzle retaining pin 39 in FIG. 10 have an overlapping position when viewed from the insertion direction, that is, a relative position from the longitudinal axis. Arranged at approximately equal positions.
[0036]
(Function)
The operation of this embodiment will be described.
In general, the diameter of the tip 18 can be reduced by decreasing the distance between the built-in objects of the tip 18. However, if the distance between the cleaning nozzle 23 and the observation lens 21 is made smaller than a certain limit, a phenomenon in which the cleaning nozzle 23 appears in the observation visual field, so-called field vignetting, occurs. In general, a gap larger than a certain size is ensured between the nozzle 23 and the observation lens 21. That is, in order to avoid field vignetting, an interval of a certain size or more is originally secured between the solid-state imaging element through-hole 35a and the air / water-feeding through-hole 35c.
On the other hand, it is generally necessary to secure a space for disposing the screw 37 for fixing the lens frame 32 holding the observation lens 21 and the nozzle retaining pin 39 for fixing the cleaning nozzle 23 at the distal end portion 18. There is.
Therefore, in the present embodiment, the screw 37 and the nozzle retaining pin 39 are formed on the thick portion of the tip component member 27 secured between the solid-state imaging element through-hole 35a and the air / water-feeding through-hole 35c. Arranged. Thereby, it is not necessary to secure a space for disposing the screw 37 and the nozzle retaining pin 39 in the tip component member 27 again. Thereby, built-in objects such as the cleaning nozzle 23 and the lens frame 32 that holds the observation lens 21 can be fixed without increasing the outer diameter of the distal end portion 18.
[0037]
(effect)
According to the present embodiment, the lens frame 32 that holds the observation lens 21 shifted in the longitudinal direction in the thick portion of the tip constituting member 27 that is originally secured between the cleaning nozzle 23 and the observation lens 21. Since the screw 37 for fixing the nozzle and the nozzle retaining pin 39 for fixing the cleaning nozzle 23 are disposed, the cleaning that is a built-in object of the tip portion 18 without increasing the outer diameter of the tip portion 18. Built-in objects such as the lens nozzle 23 and the lens frame 32 that holds the observation lens 21 can be fixed.
[0038]
The tip cover retaining pin 38 and the screw 37 may be shifted in the longitudinal direction, and the screw 37, the tip cover retaining pin 38, and the nozzle retaining pin 39 may be arranged at positions overlapping when viewed from the insertion direction. . Moreover, it is good also as a structure which provides at least 2 screw | threads and a pin for fixing another built-in thing different from this Embodiment. The nozzle retaining pin 39 may have the same structure as the screw 37.
[0039]
(Fourth embodiment)
11 to 12 relate to a fourth embodiment of the present invention. FIG. 11 is a front view of the tip portion, and FIG. 12 is a cross-sectional view taken along the line cc of FIG. In addition, the structure of the site | part which is not described in this Embodiment is a structure similar to 1st Embodiment.
[0040]
(Constitution)
As shown in FIG. 11, the distal end portion 18 is formed with a plurality of through holes for accommodating built-in objects, and the distal end surface of the distal end portion 18 has an observation lens 21, an illumination lens 25, a forceps channel 24, a washing member. A nozzle 23 is provided. The illumination lens 25 is composed of a plurality of lenses that are fitted and fixed to the lens frame 26.
As shown in FIG. 12, a flange 43 protruding in the radial direction is formed on the outer periphery on the tip side of the lens frame 26 formed in a substantially cylindrical shape. The collar portion 43 is not formed on the entire circumference, but is formed on a part of the outer circumference.
When the lens frame 26 is inserted into the front end component member 27 from the front, the collar portion 43 comes into contact with the front end component member 27, and the relative position between the lens frame 26 and the front end component member 27 is determined. As a result, the relative position between the illumination lens 25 and the distal end component member 27 and the relative position between the illumination lens 25 and the distal end cover 28 attached to the distal end of the distal end component member 27 are determined.
[0041]
(Function)
When the lens frame 26 in which the illumination lens 25 is inserted is inserted into the tip constituent member 27 from the front, the flange portion 43 comes into contact with the front surface of the tip constituent member 27. As a result, the relative position between the lens frame 26 and the tip component member 27 is determined. If the positions of the lens frame 26 and the front end surface of the frontmost illumination lens 25 and the positions of the front end component member 27 and the front surface of the front end cover 28 are determined in advance, the flange 43 and the front end component member of the lens frame 26 are determined. By abutting 27, the relative position between the front end surface of the frontmost illumination lens 25 and the front surface of the front end cover 28 can be determined. Usually, the relative position of the front end surface of the illumination lens 25 and the front surface of the front end cover 28 is determined so that the front end surface of the front end lens 28 slightly protrudes from the front surface of the front end cover 28. When the collar portion 43 is formed on the entire circumference, it is necessary to make a hole having the same diameter as the collar portion 43 in the tip cover 28 so that the collar portion 43 can be inserted. As a result, the thickness of the tip cover 28 between the hole for inserting the lens frame 26 for holding the illumination lens 25 formed in the tip cover 28 and the hole for storing other built-in objects is reduced. In addition, the thickness between the hole for inserting the lens frame 26 and the side portion of the tip cover 28 is also reduced. Then, since the tip cover 28 is made of a material that is easily damaged compared to a metal such as hard plastic for insulation, the tip cover 28 is easily broken or when the tip 18 is subjected to an impact. . If the flange portion 43 of the lens frame 26 is formed not only on the entire circumference but on a part of the outer periphery as in the present embodiment, the hole formed in the tip cover 28 may be a deformed hole that is partially enlarged. The size of the hole formed in the tip cover 28 can be made smaller than when the collar portion 43 is formed. Therefore, it is possible to ensure a large thickness between the built-in objects of the tip cover 28, and it is possible to prevent the tip cover 28 from being damaged without increasing the diameter of the tip portion 18.
[0042]
(effect)
According to the present embodiment described above, the collar portion 43 formed on the outer periphery of the lens frame 26 for positioning the illumination lens 25 with respect to the front end component member 27 by abutting against the front end component member 27 is provided on the outer periphery of the lens frame 26. The hole formed in the tip cover 28 for inserting the lens frame 26 can be made small, and the tip cover 28 can be damaged without increasing the diameter of the tip 18. Can be prevented.
[0043]
(Fifth embodiment)
FIG. 13 relates to the fifth embodiment of the present invention and is an enlarged view of the opening of the cleaning nozzle from the direction of the arrow in FIG. In addition, the structure of the site | part which is not described in this Embodiment is a structure similar to 1st Embodiment.
[0044]
(Constitution)
As shown in FIG. 13, the opening 44 of the cleaning nozzle 23 includes a roof portion 45 and side portions 46 on both sides.
The height of the roof portion 45 from the front surface of the tip cover 28 is different between the height a near the central portion and the height b near the side portions, and a <b.
[0045]
(Function)
The operation of this embodiment will be described.
The larger the size of the opening 44 of the cleaning nozzle 23, the harder it is to clog. In the present embodiment, the height of the roof portion 45 is increased in the vicinity of the side portion 46 of the opening 44, which is generally a portion that is easily clogged, so that it is difficult to clog. Moreover, since the vicinity of the center of the roof portion 45 of the cleaning nozzle 23 is lowered, the flow velocity of the jet flow at the time of water supply remains high, and the cleaning performance is not impaired.
[0046]
(effect)
According to the present embodiment, the nozzle clogging can be made difficult to occur without reducing the flow rate of water supplied from the cleaning nozzle 23.
[0047]
(Sixth embodiment)
FIGS. 14 to 15 relate to a sixth embodiment of the present invention, FIG. 14 is a cross-sectional view showing the structure of the connecting portion between the tip constituent member and the curved portion, and FIG. 15 is an enlarged cross-sectional view of FIG. FIG. In addition, the structure of the site | part which is not described in this Embodiment is a structure similar to 1st Embodiment.
[0048]
(Constitution)
FIG. 14 is an enlarged cross-sectional view of a connection portion between the distal end component member 27 of the distal end portion 18 and the first bending piece 57 of the bending portion 19.
A first bending piece 57 that extends long forward is fitted to the rear end side of the outer periphery of the tip component member 27.
A hole 55b is formed on the outer periphery of the tip component member 27, and a hole 55a is formed at a position of the first bending piece 57 corresponding to the hole of the tip component member 27. When the one bending piece 57 is fitted, the positions of the hole 55b and the hole 55a substantially coincide with each other so that they communicate with each other.
A step 55 c against which the front end face of the first bending piece 57 is abutted is formed on the peripheral portion of the tip constituting member 27, and the center of the hole 55 a is formed at a position a from the front end of the first bending piece 57. The center of the hole 55b is formed at a distance b from the step 55c, and at this time, a> b. That is, the hole 55a and the hole 55b are not formed completely at the same position, but are shifted in the longitudinal direction. As shown in FIG. 15, the bending portion retaining pin 55 is inserted into the hole 55 b through the hole 55 a, and the first bending piece 57 is fixed to the tip component member 27. .
[0049]
(Function)
Since a> b, when the bending portion retaining pin 55 is inserted into the hole 55b through the hole 55a, the first bending piece 57 is pushed forward by the bending portion retaining pin 55, and the first The front end surface of the bending piece 57 is pressed against the step 55c. Thereby, the backlash of the 1st bending piece with respect to the front-end | tip structural member 27 can be prevented. In addition, since the bending portion retaining pin 55 is sandwiched between the first bending piece 57 and the tip component member 27, the bending portion retaining pin 55 is not easily detached during assembly, and is easy to assemble.
[0050]
(effect)
According to the present embodiment described above, rattling of the bending portion 19 with respect to the distal end portion 18 is prevented. Further, the bending portion retaining pin 55 is prevented from falling off during assembly, and assemblability is improved.
[0051]
The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention.
[0052]
[Appendix]
(Additional item 1)
An elongated insertion portion to be inserted into the observation target site;
A hard tip constituent member that is a frame of the tip located at the tip of the insertion portion;
A solid-state imaging device for imaging the site to be observed assembled to the tip component member;
A circuit board on which electronic components constituting a circuit and the like for amplifying a signal output from the solid-state imaging device assembled to the tip component member are mounted;
An endoscope having a cable for transmitting a signal output from the circuit board connected to the circuit board to the hand side through the insertion portion,
Covering the periphery of the solid-state imaging device and the circuit board, formed at the rear of the tip component member so that the rear end of the rear end of the circuit board or the front end of the cable is positioned on the rear side in the insertion portion longitudinal direction, or An endoscope comprising a hard member attached to a rear portion of a tip constituent member.
[0053]
(Appendix 2)
The endoscope according to appendix 1, wherein
The hard member is formed at the rear of the tip constituent member.
[0054]
(Appendix 3)
The endoscope according to appendix 2, wherein
The rear end surface of the front end component member is positioned on the rear side of the front end of the cable.
[0055]
(Appendix 4)
The endoscope according to appendix 1 to appendix 3,
The solid-state imaging device and the connection portion between the circuit board and the cable were covered with a soft protective member.
[0056]
(Appendix 5)
The endoscope according to appendix 2 to appendix 4, wherein
The tip component is formed with a plurality of through holes for assembling a built-in object built in the tip.
A rear end surface of the through hole in which the circuit board is assembled is located behind the rear end surface of the other hole.
[0057]
(Appendix 6)
The endoscope according to appendix 1 to appendix 5, wherein
A through hole formed in the tip constituent member for assembling the solid-state image sensor and the circuit board is formed so as to surround substantially the entire circumference of the solid-state image sensor and the circuit board.
[0058]
(Appendix 7)
The endoscope according to appendix 2 to appendix 6, wherein
A cutout portion was formed in a part of the outer wall of the through hole formed in the tip constituent member for assembling the circuit board so that the through hole communicates with the outside of the tip constituent member. (Appendix 8)
The endoscope according to appendix 1, wherein
The hard member is a pipe having an inner diameter larger than the maximum diameter of the circuit board and the solid-state imaging device, which is connected to a rear end of a through hole formed in the tip constituent member for assembling the circuit board. The rear end of the pipe is located behind the rear end of the circuit board.
[0059]
(Appendix 9)
The endoscope according to appendix 5 to appendix 8, comprising:
The solid-state imaging device and the connection portion between the circuit board and the cable were covered with a soft protective member.
[0060]
(Appendix 10)
The endoscope according to appendix 2 to appendix 9, wherein
An elastic member is provided at least at a part between the solid-state imaging device, the circuit board, the cable, and the tip constituent member.
[0061]
(Appendix 11)
The endoscope according to appendix 10, wherein:
The elastic member is provided only between the rear end portion of the circuit board, the front end portion of the cable, and the tip constituent member.
[0062]
(Appendix 12)
The endoscope according to appendix 2 to appendix 9, wherein
An adhesive having elasticity even after curing is provided on at least a portion between the solid-state imaging device, the circuit board, the cable, and the tip constituent member.
[0063]
(Additional Item 13)
The endoscope according to appendix 12, wherein:
The adhesive was provided only between the rear end portion of the circuit board and the front end portion of the cable, and the tip constituent member.
[0064]
(Appendix 14)
A distal end component member which is a frame of the distal end portion of the endoscope insertion portion;
An observation lens for forming an image of an observation target portion fixed to a lens frame assembled in a through-hole formed in the tip constituent member;
A fixing member such as a screw or a pin for fixing the lens frame and the observation target part;
A cleaning nozzle for ejecting a fluid for cleaning the distal end surface of the observation lens assembled in a through hole formed in the distal end constituent member;
A first retaining member such as a screw or a pin for preventing the cleaning nozzle from falling off the tip component member;
A tip cover attached to the front surface of the tip component member;
An endoscope having a second retaining member such as a screw or a pin for preventing the distal end cover from falling off from the distal end component member,
At least two of the fixing member, the first retaining member, and the second retaining member are disposed at substantially the same radial direction and different longitudinal positions of the tip component member. Endoscope.
[0065]
(Appendix 15)
A distal end component member that is a frame of the distal end portion of the endoscope insertion portion;
An observation lens for forming an image of an observation target portion fixed to a lens frame assembled in a through-hole formed in the tip constituent member;
A fixing member such as a screw or a pin for fixing the lens frame and the observation target part;
A cleaning nozzle that ejects a fluid for cleaning the distal end surface of the observation lens assembled in a through-hole formed in the tip constituent member;
An endoscope having a retaining member such as a screw or a pin for preventing the cleaning nozzle from falling off from the tip component member,
An endoscope characterized in that the fixing member and the retaining member are disposed at substantially the same radial direction and different longitudinal positions of the tip component member.
[0066]
(Appendix 16)
The endoscope according to appendix 14 to appendix 15, wherein
The fixing member was positioned on the distal end side in the longitudinal direction from the retaining member.
[0067]
(Appendix 17)
The endoscope according to appendix 14 to appendix 15, wherein
The observation lens, the fixing member and the retaining member, and the cleaning nozzle are arranged in order in the circumferential direction around the insertion axis of the endoscope insertion portion.
[0068]
(Appendix 18)
The endoscope according to appendix 14 to appendix 15, wherein
The fixing member and the retaining member are disposed at a substantially intermediate position in the circumferential direction around the insertion axis of the endoscope insertion portion of the observation lens and the cleaning nozzle.
[0069]
(Appendix 19)
An elongated insertion portion to be inserted into the observation target site;
A tip constituting member which is a frame constituting the tip of the insertion portion;
A light guide inserted through the insertion portion for guiding illumination light;
An illumination lens that distributes the emitted light from the exit end of the light guide toward the observation site;
An endoscope having a substantially cylindrical lens frame assembled to the tip constituent member for holding the illumination lens,
An endoscope characterized in that a hook-shaped projection for positioning the lens frame relative to the tip component member is formed on a part of the outer periphery of the lens frame.
[0070]
(Appendix 20)
The endoscope according to appendix 19, wherein
The protrusion has a diameter larger than the outer periphery of the lens frame, and the outer periphery is a circular arc coaxial with the lens frame.
[0071]
(Prior art according to Supplementary Items 14 to 18)
In a conventional endoscope, for example, as shown in FIG. 2 of Japanese Utility Model Publication No. 6-42642, a stopper member for a tip cover, a fixing member for an observation lens, and a stopper member for a cleaning nozzle are provided with an endoscope. In the cross section perpendicular to the mirror insertion axis, they were arranged on the same plane.
[0072]
(Problems to be solved by the invention according to supplementary items 14 to 18)
Conventionally, as shown in Japanese Utility Model Publication No. 6-42642, the retaining member for the tip cover, the fixing member for the observation lens, and the retaining member for the cleaning nozzle are flush with each other in a cross section perpendicular to the endoscope insertion axis. The space to be placed on top was secured. As the diameter of the endoscope is reduced, each built-in object is made smaller and the space between the built-in objects is reduced, so that the placement space for the fixing member and the retaining member can be secured. The need to increase the outer diameter of the tip has come out.
[0073]
The purpose of the supplementary items 14 to 18 is to reduce the diameter of the distal end portion of the endoscope while ensuring the space for each fixing member.
[0074]
(Supplementary information on the means pertaining to supplementary items 14 to 18)
The cleaning nozzle and the observation lens cannot be closer than a certain distance to prevent vignetting by the cleaning nozzle, and there is always a space between the two. In this space, at least two of the observation lens fixing member, the cleaning nozzle retaining member, and the tip cover retaining member are arranged on a non-coplanar surface in a cross section perpendicular to the endoscope insertion axis direction, and By arranging on the same axis parallel to the endoscope insertion axis, there is no need to secure a new space for arranging the fixing member and the retaining member at another position on the circumference. The diameter of the tip can be reduced.
[0075]
(Supplementary notes on supplementary items 14 to 18)
The cleaning nozzle and the observation lens cannot be closer than a certain distance in order to prevent vignetting, and a space is formed between them. In this space, at least two of the nozzle retaining member, the tip cover retaining member, and the observation lens fixing member are non-coplanar in a cross section perpendicular to the endoscope insertion axis and parallel to the endoscope insertion axis. By arranging them on the same axis, there is no need to newly secure a space for arranging the nozzle retaining member, the tip cover retaining member and the observation lens fixing member in the distal component member, and the endoscope distal end portion The diameter can be reduced.
[0076]
(Prior art according to Supplementary Item 19 and Supplementary Item 20)
Conventionally, on the distal end side of the lens frame of the illumination lens, a flange portion called a flange portion that protrudes in the radial direction is formed on substantially the entire circumference, and the flange portion is abutted against the distal end component member from the front, thereby The relative position between the lens front end surface and the endoscope front end portion was determined. For example, in Japanese Patent Laid-Open No. 10-028669, in FIG. 2, the lens frame collar part formed over the entire circumference in order to abut against the tip component member is formed with a partially-notched recess, It was easy to hook the jig when removing from the tip component.
[0077]
(Problems to be solved by the invention according to Supplementary Item 19 and Supplementary Item 20)
Since a collar portion having an outer diameter larger than the outer periphery of the lens frame is formed on the entire outer periphery of the pipe-shaped lens frame for fixing the illumination lens, the distal end portion of the endoscope is configured. It is necessary to enlarge the diameter of the hole for fitting the lens frame in the tip component member and the tip cover attached to the tip of the tip frame so that the collar portion can be accommodated in the entire circumference. The thickness of the tip cover between the illumination lens was thin, and it was easily damaged. Further, in order to increase the wall thickness, the outer diameter of the tip cover has to be increased.
[0078]
The purpose of Additional Item 19 and Additional Item 20 is to prevent breakage of the distal end cover without increasing the outer diameter of the distal end portion of the endoscope.
[0079]
(Supplementary information on supplementary items 19 and 20)
By forming a flange partly protruding on the outer periphery of the lens frame for fixing the illumination lens, the diameter of the hole of the tip cover for inserting the lens frame is matched to the shape of the lens frame, and partly The size of the hole on the tip cover can be reduced, and the tip cover wall thickness between the illumination lens and other built-in components can be reduced without increasing the tip outer diameter. The tip cover can be prevented from being damaged.
[0080]
(Supplementary notes on supplementary items 19 and 20)
On the tip cover where the lens frame is inserted, by forming a hook portion for positioning with the tip constituent member provided on the tip side of the lens frame of the illumination lens only on a part rather than the entire circumference The hole is a different diameter hole having a large diameter part only in a part so that the collar part can be inserted, and the diameter is smaller than the diameter of the hole required when the lens frame has the collar part over the entire circumference. be able to. Therefore, the distance between the holes into which the built-in objects are inserted on the distal end cover can be increased to ensure the thickness, and the distal end cover can be prevented from being damaged without increasing the outer diameter of the distal end of the endoscope.
[0081]
【The invention's effect】
As described above, according to the present invention, an elongated insertion portion to be inserted into the observation target portion, a hard tip constituent member that is a frame of the tip portion located at the tip of the insertion portion, and the tip end component member are assembled. A solid-state imaging device for imaging the observed site to be observed, and a circuit board on which electronic components constituting a circuit for amplifying a signal output from the solid-state imaging device assembled to the tip component member are mounted; An endoscope having a cable that transmits a signal output from the circuit board connected to the circuit board to the hand side through the insertion portion, and covers the periphery of the solid-state imaging device and the circuit board, The rear end of the circuit board or the front end of the cable is formed at the rear of the front end component so that the rear end is located on the rear side in the longitudinal direction of the insertion portion or attached to the rear of the front end component. Since the hard member is provided, only the periphery of the solid-state imaging device and the circuit board is covered with the hard member, the entire tip constituent member is prevented from extending backward, and the hard portion of the tip is prevented from becoming large. However, damage to the solid-state imaging device and the circuit board can be prevented.
[Brief description of the drawings]
FIG. 1 to FIG. 6 relate to a first embodiment of the present invention, and FIG. 1 is an explanatory diagram showing an overall configuration of an endoscope apparatus.
FIG. 2 is a cross-sectional view showing the configuration of the front end portion and the front end side of the bending portion
3 is a cross-sectional view taken along the line AA in FIG.
4 is a sectional view taken along line d1-d2-d3-d4-d5 in FIG.
5 is a cross-sectional view taken along the line BB in FIG.
6 is a cross-sectional view taken along line ee of FIG.
FIG. 7 is a cross-sectional view showing a configuration of a tip portion according to a second embodiment of the present invention.
8 to 10 relate to a third embodiment of the present invention, and FIG. 8 is a cross-sectional view showing a configuration of a tip portion.
9 is a cross-sectional view taken along the line BB in FIG.
10 is a cross-sectional view taken along the line CC of FIG.
FIGS. 11 to 12 relate to a fourth embodiment of the present invention, and FIG. 11 is a front view of the tip portion.
12 is a cross-sectional view taken along the line CC in FIG.
FIG. 13 is an enlarged view of the opening of the cleaning nozzle from the direction of the arrow in FIG. 11 according to the fifth embodiment of the present invention.
14 to 15 relate to a sixth embodiment of the present invention, and FIG. 14 is a cross-sectional view showing a structure of a connecting portion between a tip constituent member and a bending portion.
15 is an enlarged cross-sectional view of FIG.
[Explanation of symbols]
1. Endoscope device
2. Endoscope
3. Light source device
4 ... Video processor
5 ... Monitor device
6 ... VTR deck
7 ... Video disc
8 ... Video printer
11 ... Light guide
12 ... Flexible tube
13 ... Operation part
14 ... Universal code
15 ... Light guide connector
16 ... Signal cable
17 ... Signal connector
18 ... tip
19: Curved part
20a ... Forceps insertion slot
20b ... Air / water inlet
21 ... Lens for observation
22 ... Solid-state imaging device
23 ... Cleaning nozzle
24 ... Forceps channel
25 ... Lens for illumination
26 ... Lens frame
27. Tip component
28 ... Tip cover
29 ... Circuit board
30 ... Cable
35a ... Through-hole for solid-state image sensor
35b ... Light guide through hole
35c ... Air / water feed through holes
35d: Forceps channel through hole
42 ... Cable front end
41a ... rear end surface (of through hole for solid-state imaging device)
41b ... Rear end surface of light guide through hole
41c ... rear end face (of air / water feed through hole)
41d ... rear end surface of the forceps channel through hole
57 ... 1st bending piece
60 ... first joint
101 ... Insertion part

Claims

An insertion section that can be inserted into a subject;
A distal end constituting member that is formed in a substantially cylindrical shape with a hard material that constitutes the distal end side of the insertion portion;
A first hole for receiving an imaging unit, which is provided in the tip component member and includes an imaging element, a circuit board electrically connected to the imaging element, and a cable connected to the circuit board;
A first rear end surface that is disposed on a proximal end side of the distal end component member and is provided with an opening of the first hole portion on the rear side of the circuit board ;
A second hole for disposing a built-in object that is provided in the tip component member and is inserted through the insertion portion;
A second rear end surface disposed on the distal end side with respect to the first rear end surface, which is disposed on the proximal end side of the distal end component member and provided with an opening of the second hole;
An endoscope characterized by comprising:

  An insertion section that can be inserted into a subject;
  A distal end constituting member that is formed in a substantially cylindrical shape with a hard material that constitutes the distal end side of the insertion portion;
  A first hole which is provided in the tip component member and houses an imaging unit including an imaging device, a circuit board electrically connected to the imaging device, and a cable connected to the circuit board;
  A first rear end surface that is disposed on a proximal end side of the distal end constituent member and provided with an opening of the first hole on a rear side of the circuit board;
  A second hole for disposing a forceps channel provided in the distal end component member and inserted through the insertion portion;
  A second rear end surface disposed on the distal end side with respect to the first rear end surface disposed on the proximal end side of the distal end component member and provided with an opening of the second hole;
  An endoscope characterized by comprising:

  An insertion section that can be inserted into a subject;
  A distal end constituting member that is formed in a substantially cylindrical shape with a hard material that constitutes the distal end side of the insertion portion;
  A first hole which is provided in the tip component member and houses an imaging unit including an imaging device, a circuit board electrically connected to the imaging device, and a cable connected to the circuit board;
  A first rear end surface that is disposed on a proximal end side of the distal end constituent member and provided with an opening of the first hole on a rear side of the circuit board;
  A second hole for disposing a light guide provided in the tip component member and inserted through the insertion portion;
  A second rear end surface disposed on the distal end side with respect to the first rear end surface disposed on the proximal end side of the distal end component member and provided with an opening of the second hole;
  An endoscope characterized by comprising:

  An insertion section that can be inserted into a subject;
  A distal end constituting member that is formed in a substantially cylindrical shape with a hard material that constitutes the distal end side of the insertion portion;
  A first hole which is provided in the tip component member and houses an imaging unit including an imaging device, a circuit board electrically connected to the imaging device, and a cable connected to the circuit board;
  A first rear end surface that is disposed on a proximal end side of the distal end constituent member and provided with an opening of the first hole on a rear side of the circuit board;
  A second hole portion for disposing an air / water pipe pipe that is provided in the distal end component member and passes through the insertion portion;
  A second rear end surface disposed on the distal end side with respect to the first rear end surface disposed on the proximal end side of the distal end component member and provided with an opening of the second hole;
  An endoscope characterized by comprising: