JP4386517B2

JP4386517B2 - Hole saw for fluid transport pipe and drilling method in fluid transport pipe using the same

Info

Publication number: JP4386517B2
Application number: JP35002599A
Authority: JP
Inventors: 晴彦清水
Original assignee: Waterworks Technology Development Organization Co Ltd
Current assignee: Waterworks Technology Development Organization Co Ltd
Priority date: 1999-12-09
Filing date: 1999-12-09
Publication date: 2009-12-16
Anticipated expiration: 2019-12-09
Also published as: JP2001162422A

Description

【０００１】
【発明の属する技術分野】
本発明は、例えば、流体輸送管に設けられた仕切弁が閉止状態のまま操作不能に陥って、その閉止姿勢にある弁体に流路確保のための開口を穿設する必要が生じた場合、或いは、流体輸送管の途中に分岐用の流体輸送管を接続して、その接続箇所の管壁に分岐口を形成する必要が生じた場合などに用いられる穿孔切削具で、詳しくは、円筒状ボディーの先端部に切削チップが設けられている流体輸送管用ホールソーの改良と、それを用いた流体輸送管内の穿孔方法に関する。
【０００２】
【従来の技術】
従来の流体輸送管用の穿孔装置では、駆動回転軸の先端部に設けたカッタ取付け部に、円筒状ボディーの先端側に切削チップを設けてあるホールソーと、該ホールソーの切削チップよりも前方に突出する状態で円筒状ボディー内の回転中心位置に配設されるセンタードリルとを取付けるとともに、前記駆動回転軸の外周側には、油圧供給制御装置からの圧油供給によって回転軸芯方向に往復駆動されるシリンダー体を外装し、このシリンダー体とカッタ取付け部との間には、流体輸送管の内周面の円周方向複数箇所に沿って摺接可能な摺接体を備え、かつ、駆動回転軸に対するシリンダー体の駆動摺動に連動して、摺接体を管径方向外方に同時に展伸移動させた摺接ガイド姿勢と管径方向内方に同時に収縮移動させた格納姿勢とに切替え作動させる芯出ガイド機構を設けていた（例えば、実公平６−３０３２７号公報参照）。
そして、流体輸送管内の特定箇所に臨む被加工体を穿孔するに、先ず、シリンダー体への圧油供給を司る油圧供給制御装置を操作して、芯出ガイド機構の摺接体を管径方向内方に収縮移動させた格納姿勢に保持し、この状態で芯出ガイド機構を流体輸送管の開口端部から手動で押込み操作する。
この押込み操作に連れてホールソー及びセンタードリルが流体輸送管内の所定位置に到達したしたとき、前記油圧供給制御装置を操作して、芯出ガイド機構の摺接体を管径方向外方に展伸移動させた摺接ガイド姿勢に切替え、ホールソー及びセンタードリルの回転軸芯を流体輸送管の管軸芯側に矯正する。この状態で駆動回転軸を介してホールソー及びセンタードリルを駆動するとともに、前記駆動回転軸に連動された撓み伝動軸を介して手動で送り込み力を付与し、流体輸送管内の特定箇所に臨む被加工体に穿孔する。
【０００３】
【発明が解決しようとする課題】
従来の流体輸送管用の穿孔装置では、ホールソー及びセンタードリルに対するカッタ取付け部を備えた駆動回転軸の外周部に、油圧供給制御装置からの圧油供給によって回転軸芯方向に往復駆動されるシリンダー体と、流体輸送管の内周面に摺接可能な複数の摺接体を備え、かつ、シリンダー体の駆動摺動に連動して、摺接体を摺接ガイド姿勢と格納姿勢とに切替え作動させる芯出ガイド機構とを組付けるため、装置全体が複雑化、重量化し、穿孔作業時における現場での取り扱いに多大の労力を要するとともに、シリンダー体への圧油供給を司る油圧供給制御装置も必要となるため、製造コストが高騰化する問題があった。
【０００４】
本発明は、上述の実状に鑑みて為されたものであって、その第１の主たる課題は、ホールソー自体が流体輸送管の内径に近い外径に構成されていることを利用した合理的な改造をもって、ホールソーの回転軸芯を流体輸送管の管軸芯側に矯正しながらも、穿孔作業時における現場での取り扱いを少ない労力で容易に行うことができ、しかも、構造の簡素化と製造コストの低廉化とを図ることのできるホールソーを提供する点にあり、第２の課題は、穿孔機の小型化、軽量化を図り易く、しかも、流体輸送管内の被加工体に対する穿孔加工精度の向上を図りつつ、円筒状ボディーの押込み作業の容易化も同時に達成することのできる流体輸送管内の穿孔方法を提供する点にある。
【０００５】
【課題を解決するための手段】
本発明の請求項１による流体輸送管用ホールソーの特徴構成は、円筒状ボディーの先端部に切削チップが設けられ、前記円筒状ボディー内の基端部の回転中心位置には、前記切削チップよりも前方に突出するセンタードリルが設けられ、該センタードリルには、前記円筒状ボディー内に入り込んだ切片の抜け出しを防止する抜止め手段が設けられているホールソーであって、
前記円筒状ボディーの外周面に、流体輸送管の内周面との接触によって、前記円筒状ボディーの回転軸芯を前記流体輸送管の管軸芯側に矯正する軸芯矯正体が設けられ、前記軸芯矯正体が前記円筒状ボディーの基端部側の外周面で、かつ、前記流体輸送管内の特定箇所に臨む被加工体に対する穿孔時に該被加工体と接触しない領域に形成されており、
前記軸芯矯正体を金属製のリングで構成し、前記軸芯矯正体とこれに径方向で相対向する前記円筒状ボディーの周壁部とを、前記軸芯矯正体が前記流体輸送管の内周面と干渉したときの抵抗力が設定値以上に増大したときに剪断又は破断されるシャーピンでカシメ固定して、前記シャーピンの剪断によって前記軸芯矯正体の少なくとも管接触部が前記円筒状ボディーから分離されるように構成されている点にある。
上記特徴構成によれば、円筒状ボディーの外周面に設けられた軸芯矯正体と流体輸送管の内周面との接触によって、円筒状ボディーの回転軸芯を流体輸送管の管軸芯側に矯正することができるばかりでなく、円筒状ボディーが流体輸送管の内径に近い外径に構成されているから、軸芯矯正体の管径方向外方への突出量も少なくて済み、しかも、軸芯矯正体を管径方向に移動自在に保持する機構やそれを油圧等で駆動制御する制御装置を削減することができる。
従って、ホールソーを構成する円筒状ボディーが流体輸送管の内径に近い外径に構成されていることを利用して、その円筒状ボディーの外周面に軸芯矯正体を設けるだけの簡単、かつ、安価な改造をもって、穿孔作業時における現場での取り扱いを少ない労力で容易に行うことができ、しかも、従来の穿孔装置に比して構造の簡素化と製造コストの低廉化とを図ることができる。
また、前記軸芯矯正体としては、センタードリルが流体輸送管内の特定箇所に臨む被加工体を穿孔するまで、円筒状ボディーの回転軸芯を流体輸送管の管軸芯側に矯正維持できれば十分であり、センタードリルが設けられていないものに比して、前記軸芯矯正体に要求される機械的強度が小さくて済み、製造コストの低廉化を促進することができる。
しかも、穿孔終了時に、ホールソー及びセンタードリルの抜き出し移動と一緒に切片も回収することができ、穿孔作業の能率化を促進することができる。
さらに、前記軸芯矯正体が、円筒状ボディーの外周面基端部側の非接触領域（被加工体と接触しない領域）に形成されているから、流体輸送管が管継手箇所等で少しへの字状に屈曲していても、円筒状ボディーの先端側の回転軸芯位置を、軸芯矯正体と流体輸送管の内周面との接触箇所を支点としての揺動によって簡単に修正することができ、流体輸送管内の所定位置へのホールソーの挿入作業（押込み作業）の容易化を図ることができるとともに、前記軸芯矯正体が被加工体の孔周縁部に圧接されることに起因する損傷や喰込み等を抑制することができる。
加えて、前記流体輸送管内の特定箇所に臨む被加工体に対してセンタードリルが穿孔作業を開始すると、前記軸芯矯正体による軸芯矯正作用が実質的に不要となり、寧ろ、軸芯矯正体が存続すれば、流体輸送管の管軸芯に対して円筒状ボディーの回転軸芯が少し傾斜している穿孔作業条件下では、円筒状ボディーの切削チップによる穿孔作業の進行に連れて、軸芯矯正体が流体輸送管の内周面に次第に強く圧接され、該軸芯矯正体で流体輸送管の内周面を損傷する可能性がある。しかし、このような事態が発生しても、本発明の場合では、前記軸芯矯正体を金属製のリングで構成し、前記軸芯矯正体とこれに径方向で相対向する前記円筒状ボディーの周壁部とを、前記軸芯矯正体が前記流体輸送管の内周面と干渉したときの抵抗力が設定値以上に増大したときに剪断又は破断されるシャーピンでカシメ固定して、前記シャーピンの剪断によって前記軸芯矯正体の少なくとも管接触部が前記円筒状ボディーから分離されるように構成されているので、前記軸芯矯正体が流体輸送管の内周面と干渉したときの抵抗力が設定値以上に増大したときに剪断又は破断して、軸芯矯正体の少なくとも管接触部が円筒状ボディーから分離されるから、該軸芯矯正体による流体輸送管の内周面の損傷を抑制することができる。
【０００６】
本発明の請求項２による流体輸送管用ホールソーの特徴構成は、前記軸芯矯正体の管軸芯方向に沿う縦断面形状が、半円状又はそれに近い類似形状に構成されている点にある。
上記特徴構成によれば、流体輸送管が管継手箇所等で屈曲していたり、環状の溝部が発生している場合でも、流体輸送管の内周面に沿って挿入（押込み）操作されるホールソーを確実、容易に通過移動させることができるとともに、その挿入作業（押込み作業）を少ない労力で容易に行うことができる。
【０００７】
本発明の請求項３による流体輸送管用ホールソーの特徴構成は、前記軸芯矯正体をカシメ固定する前記シャーピンを境界として前記軸芯矯正体の管軸芯方向に沿う縦断面形状が、前記円筒状ボディーの基端部側が半円状に構成され、先端部側が先端側ほど縮径する三角形状に構成されている点にある。
【０００８】
本発明の請求項４による流体輸送管用ホールソーの特徴構成は、円筒状ボディーの先端部に切削チップが設けられ、前記円筒状ボディー内の基端部の回転中心位置には、前記切削チップよりも前方に突出するセンタードリルが設けられ、該センタードリルには、前記円筒状ボディー内に入り込んだ切片の抜け出しを防止する抜止め手段が設けられているホールソーであって、
前記円筒状ボディーの外周面に、流体輸送管の内周面との接触によって、前記円筒状ボディーの回転軸芯を前記流体輸送管の管軸芯側に矯正する軸芯矯正体が設けられ、
前記軸芯矯正体を外輪と内輪との間に複数のボールを組付けてある転がり軸受から構成し、前記内輪を前記円筒状ボディーの基端部側の外周面で、かつ、前記流体輸送管内の特定箇所に臨む被加工体に対する穿孔時に該被加工体と接触しない領域に固着し、前記転がり軸受が前記流体輸送管の内周面と干渉したときの抵抗力が設定値以上に増大したときに前記外輪と前記内輪との間で破断分解して、前記軸芯矯正体の管接触部分に相当する前記外輪と前記ボールとが前記円筒状ボディーから分離されるように構成されている点にある。
上記特徴構成によれば、円筒状ボディーの外周面に設けられた軸芯矯正体と流体輸送管の内周面との接触によって、円筒状ボディーの回転軸芯を流体輸送管の管軸芯側に矯正することができるばかりでなく、円筒状ボディーが流体輸送管の内径に近い外径に構成されているから、軸芯矯正体の管径方向外方への突出量も少なくて済み、しかも、軸芯矯正体を管径方向に移動自在に保持する機構やそれを油圧等で駆動制御する制御装置を削減することができる。
従って、ホールソーを構成する円筒状ボディーが流体輸送管の内径に近い外径に構成されていることを利用して、その円筒状ボディーの外周面に軸芯矯正体を設けるだけの簡単、かつ、安価な改造をもって、穿孔作業時における現場での取り扱いを少ない労力で容易に行うことができ、しかも、従来の穿孔装置に比して構造の簡素化と製造コストの低廉化とを図ることができる。
また、前記軸芯矯正体としては、センタードリルが流体輸送管内の特定箇所に臨む被加工体を穿孔するまで、円筒状ボディーの回転軸芯を流体輸送管の管軸芯側に矯正維持できれば十分であり、センタードリルが設けられていないものに比して、前記軸芯矯正体に要求される機械的強度が小さくて済み、製造コストの低廉化を促進することができる。
しかも、穿孔終了時に、ホールソー及びセンタードリルの抜き出し移動と一緒に切片も回収することができ、穿孔作業の能率化を促進することができる。
さらに、前記軸芯矯正体が、円筒状ボディーの外周面基端部側の非接触領域（被加工体と接触しない領域）に形成されているから、流体輸送管が管継手箇所等で少しへの字状に屈曲していても、円筒状ボディーの先端側の回転軸芯位置を、軸芯矯正体と流体輸送管の内周面との接触箇所を支点としての揺動によって簡単に修正することができ、流体輸送管内の所定位置へのホールソーの挿入作業（押込み作業）の容易化を図ることができるとともに、前記軸芯矯正体が被加工体の孔周縁部に圧接されることに起因する損傷や喰込み等を抑制することができる。
加えて、前記流体輸送管内の特定箇所に臨む被加工体に対してセンタードリルが穿孔作業を開始すると、前記軸芯矯正体による軸芯矯正作用が実質的に不要となり、寧ろ、軸芯矯正体が存続すれば、流体輸送管の管軸芯に対して円筒状ボディーの回転軸芯が少し傾斜している穿孔作業条件下では、円筒状ボディーの切削チップによる穿孔作業の進行に連れて、軸芯矯正体が流体輸送管の内周面に次第に強く圧接され、該軸芯矯正体で流体輸送管の内周面を損傷する可能性がある。しかし、このような事態が発生しても、本発明の場合では、前記軸芯矯正体を外輪と内輪との間に複数のボールを組付けてある転がり軸受から構成し、前記内輪を前記円筒状ボディーの基端部側の外周面で、かつ、前記流体輸送管内の特定箇所に臨む被加工体に対する穿孔時に該被加工体と接触しない領域に固着し、前記転がり軸受が前記流体輸送管の内周面と干渉したときの抵抗力が設定値以上に増大したときに前記外輪と前記内輪との間で破断分解して、前記軸芯矯正体の管接触部分に相当する前記外輪と前記ボールとが前記円筒状ボディーから分離されるように構成されているので、前記軸芯矯正体が流体輸送管の内周面と干渉したときの抵抗力が設定値以上に増大したときに剪断又は破断して、軸芯矯正体の少なくとも管接触部が円筒状ボディーから分離されるから、該軸芯矯正体による流体輸送管の内周面の損傷を抑制することができる。
【００１０】
本発明の請求項５による流体輸送管内の穿孔方法の特徴構成は、前記円筒状ボディーを取付けてある回転伝動軸を、円筒状ボディーの外周面に形成された軸芯矯正体を流体輸送管の内周面に接触させた状態で流体輸送管の開口端部から押込み、前記円筒状ボディーが流体輸送管内の所定位置に到達したとき、前記回転伝動軸の基端部を、穿孔機の駆動回転軸に固定連結し、穿孔機の駆動回転軸に駆動回転力と送り力とを付与することにより、円筒状ボディーで流体輸送管内の特定箇所に臨む被加工体を穿孔する点にある。
上記特徴構成によれば、流体輸送管内の特定箇所に臨む被加工体を穿孔する場合、流体輸送管の開口端部から挿入されたホールソーの円筒状ボディーを、該円筒状ボディーを取付けてある回転伝動軸を介して流体輸送管内の所定位置にまで押込み操作する。このとき、円筒状ボディーの外周面に設けられた軸芯矯正体が流体輸送管の内周面と接触して、円筒状ボディーの回転軸芯を流体輸送管の管軸芯側に矯正することができるとともに、流体輸送管が管継手箇所等で少しへの字状に屈曲していても、円筒状ボディーの先端側の回転軸芯位置を、流体輸送管の内周面と接触する軸芯矯正体を支点としての回転伝動軸の揺動操作によって簡単に修正することができる。
そして、前記円筒状ボディーが流体輸送管内の所定位置に到達したとき、回転伝動軸の基端部を、穿孔機の駆動回転軸に固定連結して、穿孔機の駆動回転軸に駆動回転力と送り力とを付与することにより、円筒状ボディーで流体輸送管内の特定箇所に臨む被加工体を機械力で確実に穿孔することができる。
従って、流体輸送管内の所定位置への押込み作業を、穿孔機と切り離した状態で回転伝動軸を介して行うから、穿孔機の小型化、軽量化を図り易く、しかも、円筒状ボディーの回転軸芯位置を流体輸送管の管軸芯側に矯正するための軸芯矯正体を、押込み操作される円筒状ボディーの向き姿勢を変更する際の揺動支点として利用することができ、流体輸送管内の被加工体に対する穿孔加工精度の向上を図りつつ、円筒状ボディーの押込み作業の容易化も同時に達成することができる。
【００１１】
【発明の実施の形態】
〔第１実施形態〕
図１は、本発明の流体輸送管用ホールソーを示し、先端部に切削チップ１が設けられている円筒状ボディー（円筒状体又は円筒状カッター）２の基端部である底壁部２ａに、図２に示す穿孔機Ａの駆動回転軸３の連結フランジ部３Ａ又はこれに固定連結された回転伝動軸４の先端側の連結フランジ部４Ａに対して選択的にボルト５等の締結手段を介して固定連結される連結部６を形成するとともに、前記円筒状ボディー２内の底壁部２ａの回転中心位置には、前記切削チップ１よりも前方に突出するセンタードリル７を設け、該センタードリル７には、円筒状ボディー２内に入り込んだ切片１１の抜け出しを防止する抜止め手段８を設け、更に、前記円筒状ボディー２の底壁部２ａ側の外周面で、かつ、前記流体輸送管Ｐ内の特定箇所に臨む被加工体ｂに対する穿孔時に、該被加工体ｂと接触しない領域、換言すれば、穿孔時に被加工体ｂと接触する領域Ｌ外には、流体輸送管Ｐの内周面との接触によって、円筒状ボディー２の回転軸芯を流体輸送管Ｐの管軸芯Ｘ側に矯正する軸芯矯正体９が設けられている。
【００１２】
前記連結部６は、円筒状ボディー２の底壁部２ａのうち、駆動回転軸３の連結フランジ部３Ａに形成されたボルト挿通孔３ａ又は回転伝動軸４の連結フランジ部４Ａに形成されたボルト挿通孔４ａに対応する部位の各々に、締結手段のボルト５が螺合操作されるネジ孔を形成して構成されている。
【００１３】
前記センタードリル７は、円筒状ボディー２の底壁部２ａの回転軸芯位置に形成されたネジ孔２ｄに脱着自在に螺合固定される取付け軸７Ａと、該取付け軸７Ａに付け替え自在に螺合固定されるドリル本体７Ｂとから構成されている。
【００１４】
前記抜止め手段８は、センタードリル７のドリル本体７Ｂのうち、穿孔終了時に被加工体ｂを貫通する部位の周方向複数箇所に、回転軸芯方向に沿う溝部８ａを形成し、各溝部８ａ内には、先端側を支点として径方向に揺動起伏自在な抜止め部材８ｂを枢着するとともに、各抜止め部材８ｂの枢支部には、抜止め部材８ｂを径方向外方に突出する起立姿勢に付勢する弾性付勢体の一例である捻じりコイルスプリング８ｃを設けて構成されている。
【００１５】
前記軸芯矯正体９は、砲金等の金属製のリングから構成されていて、その管軸芯方向に沿う縦断面形状が、外周面９ａ側が曲面となる半円状又はほぼ半円状に構成されている。
そして、この軸芯矯正体９の円周方向複数箇所とこれに径方向で相対向する円筒状ボディー２の周壁部２ｂの円周方向複数箇所とを、軸芯矯正体９が流体輸送管Ｐの内周面と干渉したときの抵抗力が設定値以上に増大したとき、換言すれば、軸芯矯正体９が流体輸送管Ｐの内周面に圧接されたときの剪断力が設値以上に増大したときに剪断されるシャーピン１０でそれぞれカシメ固定して、軸芯矯正体９が流体輸送管Ｐの内周面に圧接されて抵抗力（剪断力）が設定値以上に増大したとき、前記シャーピン１０の剪断によって軸芯矯正体９全体が円筒状ボディー２から分離されるように構成されている。
【００１６】
前記円筒状ボディー２の周壁部２ｂ及び底壁部２ａには、水抜き及び切粉排出のための貫通孔２ｅが形成されている。
【００１７】
前記穿孔機Ａとしては種々の構造のものが存在するが、その一例を挙げると、図２に示すように、前記ケーシング１５に、駆動回転軸３を相対回転並びにその回転軸芯方向に相対摺動自在に支承し、この駆動回転軸３内に、当該駆動回転軸３の先端部（送込み側端部）側に対して相対回転のみ自在に連結された第１送り軸１６と、該第１送り軸１６の後端部（戻り側端部）の外周面に形成された雄ネジ１６ａに螺合する雌ネジ１７ａを備えた第２送り軸１７とを同芯状態で配設するとともに、前記ケーシング１５から突出する第２送り軸１７の後端部には手動ハンドル１８を止着してある。
【００１８】
また、前記駆動回転軸３の後端部の外周面に対して回転軸芯方向に摺動自在にスプライン嵌合された駆動筒軸１９を、前記ケーシング１５に回転のみ自在に支承させ、この駆動筒軸１９の先端部側近くには、図外の電動モータやエンジン等の原動部に連動された駆動入力軸２０のウォーム２１に噛合するウォームホイール２２を固着するとともに、前記駆動筒軸１９の後端部に外嵌固着された食違い歯車２３から第２送り軸１７の後端側に外嵌固着された平歯車２４への動力伝達系の途中には、原動部側の回転力を第２送り軸１７に伝達する自動送り状態と、手動ハンドル１８による第２送り軸１７の回転操作を許容する手動送り状態とに切替え操作自在なクラッチ２５が設けられている。
【００１９】
そして、前記クラッチ２５が自動送り状態に操作されている状態で、前記原動部の回転力が駆動筒軸１９に伝達されると、この駆動筒軸１９に対して摺動自在にスプライン嵌合されている駆動回転軸３が駆動回転されると同時に、前記駆動筒軸１９にクラッチ２５を介して連動されている第２送り軸１７が駆動回転され、この第２送り軸１７に螺合連動されている第１送り軸１６が伸展作動し、駆動回転軸３が駆動回転されながら送り出される。つまり、前記電動モータやエンジン等の原動部の駆動により、駆動回転軸３に駆動回転力と送り力とを付与する。
【００２０】
次に、上述の如く構成された流体輸送管用ホールソー用いた流体輸送管内の穿孔方法について説明する。
図３〜図６は、流体輸送管Ｐ内の特定箇所に臨む被加工体の一例で、貯水プールＣに開口する流体輸送管Ｐの途中介在した仕切弁Ｂが閉止状態のまま操作不能に陥って、その閉止姿勢にある弁体ｂに流路確保のための開口２７を穿設する場合の穿孔方法を示す。
まず、図３に示すように、円筒状ボディー２の底壁部２ａに形成した連結部６と回転伝動軸４の連結フランジ部４Ａとを締結手段のボルト５で固定連結したのち、流体輸送管Ｐの開口端部から挿入されたホールソーの円筒状ボディー２を、該円筒状ボディー２の外周面に形成された軸芯矯正体９を流体輸送管Ｐの内周面に接触させた状態で回転伝動軸４を介して流体輸送管Ｐ内の所定位置にまで押込み操作する。
このとき、円筒状ボディー２の外周面に設けられた軸芯矯正体９が流体輸送管Ｐの内周面と接触して、円筒状ボディー２の回転軸芯を流体輸送管Ｐの管軸芯Ｘ側に矯正することができるとともに、流体輸送管Ｐが管継手Ｄの介在箇所等で少しへの字状に屈曲していても、円筒状ボディー２の先端側の回転軸芯位置を、流体輸送管Ｐの内周面と接触する軸芯矯正体９を支点としての回転伝動軸４の揺動操作によって簡単に修正することができる。
【００２１】
そして、図４、図５に示すように、前記円筒状ボディー２が流体輸送管Ｐ内の所定位置に到達したとき、回転伝動軸４の基端部に形成された連結フランジ部４Ｂと、穿孔機Ａの駆動回転軸３の連結フランジ３Ａとを締結手段のボルト５で固定連結したのち、穿孔機Ａの原動部を駆動して、駆動回転軸３に駆動回転力と送り力とを付与することにより、センタードリル７及び円筒状ボディー２によって、流体輸送管Ｐ内の特定箇所に臨む弁体（被加工体）ｂに開口２７を穿設する。
【００２２】
また、前記仕切弁Ｂの弁体ｂに対してセンタードリル７が穿孔作業を開始すると、前記軸芯矯正体９による軸芯矯正作用が実質的に不要となり、寧ろ、軸芯矯正体９が存続すれば、流体輸送管Ｐの管軸芯Ｘに対して円筒状ボディー２の回転軸芯が少し傾斜している穿孔作業条件下では、円筒状ボディー２の切削チップ１による穿孔作業の進行に連れて、円筒状ボディー２と一体移動する軸芯矯正体９が流体輸送管Ｐの内周面に次第に強く圧接され、該軸芯矯正体９で流体輸送管Ｐの内周面を損傷する可能性がある。しかし、このような事態が発生しても、前記軸芯矯正体９が流体輸送管Ｐの内周面と干渉（圧接）して抵抗力（剪断力）が設値以上に増大したとき、前記軸芯矯正体９を取付けているシャーピン１０が剪断されて、該軸芯矯正体９全体が円筒状ボディー２から分離されるから、該軸芯矯正体２による流体輸送管Ｐの内周面の損傷を抑制することができる。
【００２３】
尚、前記穿孔機Ａは、貯水プールＣの底面に設置された架台Ｅ上に載置固定されていて、該架台Ｅの図外の高さ調節手段により、円筒状ボディー２の回転軸芯位置を流体輸送管Ｐの管軸芯Ｘ側に矯正維持した状態で、回転伝動軸４の回転軸芯と穿孔機Ａの駆動回転軸３の回転軸芯とが合致するように調節する。
【００２４】
また、図５、図６に示すように、仕切弁Ｂの弁体ｂに対する穿孔工程が終了すると、穿孔機Ａの原動部を駆動停止するとともに、駆動回転軸３と回転伝動軸４との連結を解除したのち、センタードリル７及び円筒状ボディー２を流体輸送管Ｐの開口端部側に手動で引抜き移動させる。このとき、円筒状ボディー２内に入り込んだ切片１１の抜け出しが抜止め手段８の抜止め部材８ｂによって阻止されているから、円筒状ボディー２及びセンタードリル７の抜き出し移動と一緒に切片１１も回収することができる。
【００２５】
〔第２実施形態〕
上述の第１実施形態では、前記軸芯矯正体９が流体輸送管Ｐの内周面と干渉（圧接）して抵抗力（剪断力）が設定値以上に増大したとき、前記軸芯矯正体９を取付けているシャーピン１０が剪断されて、該軸芯矯正体９全体が円筒状ボディー２から分離されるように構成したが、図７に示すように、前記軸芯矯正体９を、外輪９Ａと内輪９Ｂとの間に複数のボール９Ｃを組付けてある転がり軸受から構成し、そのうち、前記内輪９Ｂを、前記円筒状ボディー２の底壁部２ａ側の外周面で、かつ、前記流体輸送管Ｐ内の特定箇所に臨む被加工体ｂに対する穿孔時に該被加工体ｂと接触しない領域に固着し、もって、前記軸芯矯正体９が流体輸送管Ｐの内周面と干渉（圧接）して抵抗力（剪断力）が設定値以上に増大したとき、前記軸芯矯正体９を構成する転がり軸受の外輪９Ａと内輪９Ｂとの間で破断分解して、軸芯矯正体９の管接触部分に相当する外輪９Ａとボール９Ｃとが円筒状ボディー２から分離されるように構成してもよい。
【００２６】
また、前記軸芯矯正体９を構成する転がり軸受の外輪９Ａと流体輸送管Ｐの内周面との接触によって、円筒状ボディー２の回転軸芯を流体輸送管Ｐの管軸芯Ｘ側に矯正するように構成してある。
尚、その他の構成は、第１実施形態で説明した構成と同一であるから、同一の構成箇所には、第１実施形態と同一の番号を付記してそれの説明は省略する。
【００２７】
〔その他の実施形態〕
（１）上述の実施形態では、前記軸芯矯正体９が流体輸送管Ｐの内周面と干渉したときの抵抗力が設定値以上に増大したときに剪断又は破断して、軸芯矯正体９の全体、又は、管接触部を含む一部が円筒状ボディー２から分離されるように構成したが、前記軸芯矯正体９の管接触部のみが円筒状ボディー２から分離されるように構成してもよい。
（２）上述の実施形態では、前記軸芯矯正体９を、円筒状ボディー２の基端部側の外周面で、かつ、穿孔時に被加工体ｂと接触しない領域の回転軸芯方向の一箇所に形成したが、この前記軸芯矯正体９を、円筒状ボディー２の基端部側の外周面で、かつ、前記被加工体ｂに対する非接触領域の回転軸芯方向の複数箇所に形成して実施してもよい。
（３）上述の実施形態では、前記軸芯矯正体９の管軸芯方向に沿う縦断面形状を、半円状又はほぼ半円状に形成したが、図８に示すように、前記軸芯矯正体９の管軸芯方向に沿う縦断面形状を、丸みのある三角形状等に構成して実施してもよく、更に、この軸芯矯正体９の管軸芯方向に沿う縦断面形状を、半楕円形状や丸みのある台形状、或いは、前述した各形状の類似形状に形成してもよい。
【００２８】
【図面の簡単な説明】
【図１】本発明の流体輸送管用ホールソーの第１実施形態を示す拡大縦断面図
【図２】穿孔機の断面図
【図３】流体輸送管内の穿孔方法を示す工程図
【図４】流体輸送管内の穿孔方法を示す工程図
【図５】流体輸送管内の穿孔方法を示す工程図
【図６】流体輸送管内の穿孔方法を示す工程図
【図７】本発明の流体輸送管用ホールソーの第２実施形態を示す要部の拡大縦断面図
【図８】本発明の流体輸送管用ホールソーの第３実施形態を示す要部の拡大縦断面図
【符号の説明】
Ａ穿孔機
ｂ被加工体
Ｐ流体輸送管
Ｘ管軸芯
１切削チップ
２円筒状ボディー
３駆動回転軸
４回転伝動軸
７センタードリル
８抜止め手段
９軸芯矯正体
１１切片[0001]
BACKGROUND OF THE INVENTION
In the present invention, for example, when the gate valve provided in the fluid transport pipe is closed and cannot be operated, and it is necessary to drill an opening for securing the flow path in the valve body in the closed posture. Alternatively, a drilling cutting tool used when a branching fluid transport pipe is connected in the middle of the fluid transport pipe and a branch port needs to be formed in the pipe wall of the connecting portion. The present invention relates to an improvement in a hole saw for a fluid transport pipe in which a cutting tip is provided at the tip of a cylindrical body, and a drilling method in the fluid transport pipe using the same.
[0002]
[Prior art]
In a conventional perforating device for a fluid transport pipe, a hole saw in which a cutting tip is provided on the tip end side of a cylindrical body at a cutter mounting portion provided at the tip end of a drive rotating shaft, and the hole saw projects forward from the cutting tip. In this state, a center drill disposed at the center of rotation in the cylindrical body is mounted, and the outer periphery of the drive rotation shaft is reciprocated in the direction of the rotation axis by the supply of pressure oil from the hydraulic supply control device. The cylinder body to be mounted is packaged, and a sliding contact body is provided between the cylinder body and the cutter mounting portion, which is slidable along a plurality of circumferential directions on the inner peripheral surface of the fluid transport pipe, and is driven. In conjunction with the drive sliding of the cylinder body with respect to the rotating shaft, the sliding contact position is simultaneously extended and moved outward in the pipe radial direction, and the retracted position is simultaneously contracted and moved inward in the pipe radial direction. Switching operation Thereby it was provided with a centering guide mechanism (see, for example, the actual fair 6-30327 JP).
Then, in order to drill a workpiece facing a specific location in the fluid transport pipe, first, the hydraulic pressure supply control device that controls the pressure oil supply to the cylinder body is operated, and the sliding contact body of the centering guide mechanism is moved in the pipe radial direction. The retracted and retracted position is maintained, and the centering guide mechanism is manually pushed from the opening end of the fluid transport pipe in this state.
When the hole saw and the center drill reach a predetermined position in the fluid transport pipe in accordance with the pushing operation, the hydraulic pressure supply control device is operated to extend the sliding contact body of the centering guide mechanism outward in the pipe radial direction. Switch to the moved sliding contact guide posture, and correct the rotation axis of the hole saw and center drill to the tube axis side of the fluid transport pipe. In this state, the hole saw and the center drill are driven via the drive rotary shaft, and the feed force is manually applied via the bending transmission shaft linked to the drive rotary shaft, so that the workpiece that faces a specific location in the fluid transport pipe is processed. Perforate the body.
[0003]
[Problems to be solved by the invention]
In a conventional drilling device for a fluid transport pipe, a cylinder body that is driven to reciprocate in the direction of the axis of rotation by pressure oil supply from a hydraulic pressure supply control device on the outer periphery of a drive rotation shaft provided with a cutter mounting portion for a hole saw and a center drill. And a plurality of sliding contact bodies that can be slidably contacted with the inner peripheral surface of the fluid transport pipe, and in conjunction with the driving sliding of the cylinder body, the sliding contact body is switched between a sliding guide position and a retracted position. Since the centering guide mechanism to be assembled is complicated, the entire device becomes complicated and heavy, and it takes a lot of labor for handling on site during drilling work, and a hydraulic supply control device that controls the supply of pressure oil to the cylinder body is also available Since this is necessary, there is a problem that the manufacturing cost increases.
[0004]
The present invention has been made in view of the above-mentioned actual situation, and the first main problem is that the hole saw itself is configured to have an outer diameter close to the inner diameter of the fluid transport pipe. By remodeling, while correcting the rotary shaft core of the hole saw to the tube shaft core side of the fluid transport pipe, it can be easily handled on site at the time of drilling work, and the structure is simplified and manufactured. The second problem is to provide a hole saw capable of reducing the cost, and the second problem is that the drilling machine can be easily reduced in size and weight, and the drilling accuracy of the workpiece in the fluid transport pipe is improved. An object of the present invention is to provide a drilling method in a fluid transport pipe, which can improve the push-in operation of the cylindrical body and at the same time achieve improvement.
[0005]
[Means for Solving the Problems]
  The characteristic configuration of the hole saw for a fluid transport pipe according to claim 1 of the present invention is:A cutting tip is provided at the distal end portion of the cylindrical body, and a center drill that protrudes forward from the cutting tip is provided at the rotation center position of the base end portion in the cylindrical body. A hole saw provided with retaining means for preventing the section that has entered the cylindrical body from coming out,
  AboveBy contacting the outer peripheral surface of the cylindrical body with the inner peripheral surface of the fluid transport pipe,AboveThe axis of rotation of the cylindrical bodyAboveAn axis corrector is provided on the pipe axis side of the fluid transport pipe.The shaft core correcting body is formed on the outer peripheral surface of the cylindrical body on the base end side and in a region that does not come into contact with the workpiece when drilling the workpiece facing a specific location in the fluid transport pipe. And
  The shaft core straightening body is formed of a metal ring, and the shaft core straightening body and the peripheral wall portion of the cylindrical body opposed to each other in the radial direction are connected to each other in the fluid transport pipe. Caulking and fixing with a shear pin that is sheared or broken when the resistance force when interfering with the peripheral surface exceeds a set value, and at least the tube contact portion of the shaft core correction body is sheared by the shear pin and the cylindrical body Configured to be separated fromThere is in point.
  According to the above characteristic configuration, the rotation axis of the cylindrical body is moved to the tube axis side of the fluid transport pipe by the contact between the axial core correcting body provided on the outer peripheral surface of the cylindrical body and the inner peripheral surface of the fluid transport pipe. In addition, the cylindrical body is configured to have an outer diameter close to the inner diameter of the fluid transport pipe, so that the amount of protrusion of the axial core correction body outward in the pipe diameter direction can be reduced. Further, it is possible to reduce a mechanism for holding the shaft core correcting body so as to be movable in the tube diameter direction and a control device for driving and controlling the same with hydraulic pressure.
  Therefore, using the fact that the cylindrical body constituting the hole saw is configured to have an outer diameter close to the inner diameter of the fluid transport pipe, it is easy to simply provide an axis correction body on the outer peripheral surface of the cylindrical body, and With inexpensive modifications, handling on site during drilling operations can be easily performed with little effort, and the structure can be simplified and the manufacturing cost can be reduced compared to conventional drilling devices. .
  In addition, as the axis corrector, it is sufficient if the rotation axis of the cylindrical body can be corrected and maintained on the tube axis side of the fluid transport pipe until the center drill drills a workpiece facing a specific location in the fluid transport pipe. Thus, the mechanical strength required for the shaft core correction body is small compared to the case where no center drill is provided, and the reduction in manufacturing cost can be promoted.
  In addition, at the end of drilling, the section can be collected together with the extraction movement of the hole saw and center drill, and the efficiency of drilling work can be promoted.
  Further, since the shaft core correcting body is formed in a non-contact region (region not in contact with the workpiece) on the outer peripheral surface proximal end side of the cylindrical body, the fluid transport pipe is slightly moved at the pipe joint portion or the like. Even if it is bent in the shape of a circle, the position of the rotational axis on the tip side of the cylindrical body is easily corrected by swinging with the contact point between the axial core corrector and the inner peripheral surface of the fluid transport pipe as a fulcrum. It is possible to facilitate the hole saw insertion work (pushing work) into a predetermined position in the fluid transport pipe, and the shaft core correction body is brought into pressure contact with the hole peripheral portion of the workpiece. Damage and biting can be suppressed.
  In addition, when the center drill starts drilling work on a workpiece facing a specific location in the fluid transport pipe, the shaft core correction body by the shaft core correction body becomes substantially unnecessary. If the drilling work conditions are such that the rotational axis of the cylindrical body is slightly inclined with respect to the pipe axis of the fluid transport pipe, the shaft moves as the drilling progresses with the cutting tip of the cylindrical body. There is a possibility that the core straightening body is gradually pressed strongly against the inner peripheral surface of the fluid transport pipe and the inner peripheral surface of the fluid transport pipe is damaged by the shaft core straightening body. However, even if such a situation occurs, in the case of the present invention, the shaft core straightened body is formed of a metal ring, and the shaft core straightened body and the cylindrical body that is opposed to this in the radial direction. And the shear pin is fixed by a shear pin that is sheared or broken when a resistance force when the axial core correcting body interferes with an inner peripheral surface of the fluid transport pipe increases beyond a set value. Since at least the tube contact portion of the axial core correcting body is separated from the cylindrical body by shearing, the resistance force when the axial core correcting body interferes with the inner peripheral surface of the fluid transport pipe Since the shearing or breaking occurs when at least the set value exceeds the set value, at least the tube contact portion of the axial core correction body is separated from the cylindrical body. Can be suppressed.
[0006]
  The characteristic configuration of the hole saw for a fluid transport pipe according to claim 2 of the present invention is as follows:The longitudinal cross-sectional shape along the tube axis direction of the axial core correction body is configured in a semicircular shape or a similar shape close thereto.It is in the point.
  According to the above characteristic configuration, the hole saw that is inserted (pushed) along the inner peripheral surface of the fluid transport pipe even when the fluid transport pipe is bent at a pipe joint or the like or an annular groove is generated. Can be surely and easily moved through and the insertion operation (push-in operation) can be easily performed with little effort.
[0007]
  The characteristic configuration of the hole saw for a fluid transport pipe according to claim 3 of the present invention is as follows:The longitudinal cross-sectional shape along the tube axis direction of the axial core correcting body with the shear pin for caulking and fixing the axial core correcting body as a boundary, the proximal end side of the cylindrical body is configured in a semicircular shape, and the distal end side is It is configured in a triangular shape that decreases in diameter toward the tip side.There is in point.
[0008]
  The characteristic configuration of the hole saw for a fluid transport pipe according to claim 4 of the present invention is:A cutting tip is provided at the distal end portion of the cylindrical body, and a center drill that protrudes forward from the cutting tip is provided at the rotation center position of the base end portion in the cylindrical body. A hole saw provided with retaining means for preventing the section that has entered the cylindrical body from coming out,
  An axial core correction body is provided on the outer peripheral surface of the cylindrical body to correct the rotational axis of the cylindrical body to the tube axis side of the fluid transport pipe by contact with the inner peripheral surface of the fluid transport pipe.
  The shaft core correcting body is composed of a rolling bearing in which a plurality of balls are assembled between an outer ring and an inner ring, and the inner ring is an outer peripheral surface on the base end side of the cylindrical body, and in the fluid transport pipe When the drilling of the workpiece facing the specific location is fixed to a region that does not come into contact with the workpiece, and the resistance force when the rolling bearing interferes with the inner peripheral surface of the fluid transport pipe increases beyond a set value And the outer ring and the ball are separated from the cylindrical body by breaking and disassembling between the outer ring and the inner ring.It is in the point which is comprised.
  According to the above characteristic configuration, the rotation axis of the cylindrical body is moved to the tube axis side of the fluid transport pipe by the contact between the axial core correcting body provided on the outer peripheral surface of the cylindrical body and the inner peripheral surface of the fluid transport pipe. In addition, the cylindrical body is configured to have an outer diameter close to the inner diameter of the fluid transport pipe, so that the amount of protrusion of the axial core correction body outward in the pipe diameter direction can be reduced. Further, it is possible to reduce a mechanism for holding the shaft core correcting body so as to be movable in the tube diameter direction and a control device for driving and controlling the same with hydraulic pressure.
  Therefore, using the fact that the cylindrical body constituting the hole saw is configured to have an outer diameter close to the inner diameter of the fluid transport pipe, it is easy to simply provide an axis correction body on the outer peripheral surface of the cylindrical body, and With inexpensive modifications, handling on site during drilling operations can be easily performed with little effort, and the structure can be simplified and the manufacturing cost can be reduced compared to conventional drilling devices. .
  In addition, as the axis corrector, it is sufficient if the rotation axis of the cylindrical body can be corrected and maintained on the tube axis side of the fluid transport pipe until the center drill drills a workpiece facing a specific location in the fluid transport pipe. Thus, the mechanical strength required for the shaft core correction body is small compared to the case where no center drill is provided, and the reduction in manufacturing cost can be promoted.
  In addition, at the end of drilling, the section can be collected together with the extraction movement of the hole saw and center drill, and the efficiency of drilling work can be promoted.
  Further, since the shaft core correcting body is formed in a non-contact region (region not in contact with the workpiece) on the outer peripheral surface proximal end side of the cylindrical body, the fluid transport pipe is slightly moved at the pipe joint portion or the like. Even if it is bent in the shape of a circle, the position of the rotational axis on the tip side of the cylindrical body is easily corrected by swinging with the contact point between the axial core corrector and the inner peripheral surface of the fluid transport pipe as a fulcrum. It is possible to facilitate the hole saw insertion work (pushing work) into a predetermined position in the fluid transport pipe, and the shaft core correction body is brought into pressure contact with the hole peripheral portion of the workpiece. Damage and biting can be suppressed.
  In addition, when the center drill starts drilling work on a workpiece facing a specific location in the fluid transport pipe, the shaft core correction body by the shaft core correction body becomes substantially unnecessary. If the drilling work conditions are such that the rotational axis of the cylindrical body is slightly inclined with respect to the pipe axis of the fluid transport pipe, the shaft moves as the drilling progresses with the cutting tip of the cylindrical body. There is a possibility that the core straightening body is gradually pressed strongly against the inner peripheral surface of the fluid transport pipe and the inner peripheral surface of the fluid transport pipe is damaged by the shaft core straightening body. However, even if such a situation occurs, in the case of the present invention, the shaft core correcting body is composed of a rolling bearing in which a plurality of balls are assembled between an outer ring and an inner ring, and the inner ring is formed into the cylinder. An outer peripheral surface on the base end side of the cylindrical body and fixed to a region that does not contact the workpiece when drilling the workpiece facing a specific location in the fluid transport pipe, and the rolling bearing is connected to the fluid transport pipe. The outer ring and the ball corresponding to the tube contact portion of the shaft core correction body are broken and decomposed between the outer ring and the inner ring when the resistance force when interfering with the inner peripheral surface increases to a set value or more. Are separated from the cylindrical body, so that the shear force or breakage occurs when the resistance force when the shaft core correction body interferes with the inner peripheral surface of the fluid transport pipe increases beyond a set value. Then, at least the tube contact part of the shaft core correction body is a circle. Since separated from Jo body, it is possible to suppress damage to the inner circumferential surface of the fluid transport pipe by the mandrel straightening member.
[0010]
  Claims of the invention5The characteristic configuration of the drilling method in the fluid transport pipe is that the rotational transmission shaft to which the cylindrical body is attached is brought into contact with the inner peripheral surface of the fluid transport pipe with the shaft core correction body formed on the outer peripheral surface of the cylindrical body. When the cylindrical body reaches a predetermined position in the fluid transport pipe, the base end of the rotary transmission shaft is fixedly connected to the drive rotary shaft of the drilling machine, By applying a driving rotational force and a feeding force to the driving rotary shaft of the drilling machine, a cylindrical body is used to drill a workpiece facing a specific location in the fluid transport pipe.
  According to the above characteristic configuration, when drilling a workpiece facing a specific location in the fluid transport pipe, the cylindrical body of the hole saw inserted from the opening end of the fluid transport pipe is rotated with the cylindrical body attached. A push operation is performed to a predetermined position in the fluid transport pipe through the transmission shaft. At this time, the shaft core correcting body provided on the outer peripheral surface of the cylindrical body is in contact with the inner peripheral surface of the fluid transport pipe, and the rotating shaft core of the cylindrical body is corrected to the tube core side of the fluid transport pipe. The shaft center that contacts the inner peripheral surface of the fluid transport pipe with the position of the rotational shaft core on the tip side of the cylindrical body even if the fluid transport pipe is bent in a slightly U-shape at the pipe joint. It can be easily corrected by the swinging operation of the rotary transmission shaft with the corrector as a fulcrum.
  Then, when the cylindrical body reaches a predetermined position in the fluid transport pipe, the base end portion of the rotary transmission shaft is fixedly connected to the drive rotary shaft of the drilling machine, and the driving rotary force and the driving rotary shaft of the drilling machine are By applying the feeding force, it is possible to surely pierce the workpiece that faces the specific location in the fluid transport pipe with the cylindrical body by the mechanical force.
  Therefore, since the pushing operation to the predetermined position in the fluid transport pipe is performed through the rotary transmission shaft in a state separated from the drilling machine, the drilling machine can be easily reduced in size and weight, and the rotating shaft of the cylindrical body is also provided. An axial core correction body for correcting the core position to the pipe axis side of the fluid transport pipe can be used as a swing fulcrum when changing the orientation of the cylindrical body to be pushed in. The push-in operation of the cylindrical body can be facilitated at the same time while improving the drilling accuracy of the workpiece.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
FIG. 1 shows a hole saw for a fluid transport pipe according to the present invention, and a bottom wall portion 2a which is a base end portion of a cylindrical body (cylindrical body or cylindrical cutter) 2 provided with a cutting tip 1 at a distal end portion, The connecting flange portion 3A of the driving rotary shaft 3 of the drilling machine A shown in FIG. 2 or the connecting flange portion 4A on the distal end side of the rotary transmission shaft 4 fixedly connected thereto is selectively connected with fastening means such as a bolt 5 or the like. And a center drill 7 projecting forward from the cutting tip 1 is provided at the rotational center position of the bottom wall 2a in the cylindrical body 2. 7 is provided with a retaining means 8 for preventing the section 11 that has entered the cylindrical body 2 from slipping out, and further on the outer peripheral surface of the cylindrical body 2 on the bottom wall 2a side, and the fluid transport pipe. Facing a specific place in P When drilling the workpiece b, the region that does not contact the workpiece b, that is, outside the region L that contacts the workpiece b at the time of drilling, is in contact with the inner peripheral surface of the fluid transport pipe P. An axial core correcting body 9 is provided for correcting the rotational axis of the cylindrical body 2 toward the pipe axis X side of the fluid transport pipe P.
[0012]
The connecting portion 6 includes a bolt insertion hole 3 a formed in the connecting flange portion 3 A of the drive rotating shaft 3 or a bolt formed in the connecting flange portion 4 A of the rotating transmission shaft 4 in the bottom wall portion 2 a of the cylindrical body 2. A screw hole into which the bolt 5 of the fastening means is screwed is formed in each part corresponding to the insertion hole 4a.
[0013]
The center drill 7 includes a mounting shaft 7A that is detachably screwed and fixed to a screw hole 2d formed at the position of the rotational axis of the bottom wall 2a of the cylindrical body 2, and a screw that can be replaced with the mounting shaft 7A. It is comprised from the drill main body 7B fixed together.
[0014]
The retaining means 8 forms groove portions 8a along the rotation axis direction at a plurality of circumferential positions in the portion of the drill body 7B of the center drill 7 that penetrates the workpiece b when drilling is completed. Inside, a retaining member 8b that can swing up and down in the radial direction with the tip side as a fulcrum is pivotally attached, and the retaining member 8b protrudes radially outward at a pivotal support portion of each retaining member 8b. A torsion coil spring 8c, which is an example of an elastic biasing body that biases to a standing posture, is provided.
[0015]
The shaft core correcting body 9 is composed of a metal ring such as a gun metal, and the longitudinal cross-sectional shape along the tube axis direction is a semicircular shape or a substantially semicircular shape in which the outer peripheral surface 9a side is a curved surface. Has been.
Then, the axial core correcting body 9 is connected to the fluid transport pipe P between the plurality of circumferential direction portions of the axial core correcting body 9 and the plurality of circumferential direction portions of the peripheral wall portion 2b of the cylindrical body 2 opposed to each other in the radial direction. When the resistance force when interfering with the inner peripheral surface of the fluid increases beyond a set value, in other words, the shearing force when the shaft core correcting body 9 is pressed against the inner peripheral surface of the fluid transport pipe P is greater than the set value. When the shear pin 10 is sheared and fixed, and the shaft core correcting body 9 is pressed against the inner peripheral surface of the fluid transport pipe P, and the resistance force (shearing force) increases to a set value or more, The shaft center correcting body 9 as a whole is separated from the cylindrical body 2 by shearing of the shear pin 10.
[0016]
Through holes 2e for draining water and discharging chips are formed in the peripheral wall 2b and the bottom wall 2a of the cylindrical body 2.
[0017]
As the drilling machine A, there are various types of structures. For example, as shown in FIG. 2, the drive rotary shaft 3 is relatively rotated in the casing 15 and is relatively slid in the direction of the rotary axis as shown in FIG. A first feed shaft 16 which is supported in a freely movable manner and is connected to the tip end portion (feed side end portion) side of the drive rotary shaft 3 only in a relative rotation manner. A second feed shaft 17 having a female screw 17a screwed to a male screw 16a formed on the outer peripheral surface of the rear end portion (return side end portion) of the first feed shaft 16 is disposed in a concentric state. A manual handle 18 is fixed to the rear end portion of the second feed shaft 17 protruding from the casing 15.
[0018]
A drive cylinder shaft 19 that is spline-fitted to the outer peripheral surface of the rear end portion of the drive rotary shaft 3 so as to be slidable in the rotational axis direction is supported on the casing 15 so as to be rotatable only. A worm wheel 22 that meshes with a worm 21 of a drive input shaft 20 interlocked with a driving portion such as an electric motor or an engine (not shown) is fixed near the distal end side of the cylindrical shaft 19, and the drive cylindrical shaft 19 In the middle of the power transmission system from the staggered gear 23 that is externally fitted and fixed to the rear end portion to the spur gear 24 that is externally fitted and fixed to the rear end side of the second feed shaft 17, the rotational force on the prime mover side is increased. A clutch 25 is provided that can be switched between an automatic feed state that is transmitted to the two-feed shaft 17 and a manual feed state that allows a rotation operation of the second feed shaft 17 by the manual handle 18.
[0019]
When the rotational force of the prime mover is transmitted to the drive cylinder shaft 19 with the clutch 25 being operated in the automatic feed state, the drive cylinder shaft 19 is slidably splined. Simultaneously with the drive rotation shaft 3 being driven and rotated, the second feed shaft 17 linked to the drive cylinder shaft 19 via the clutch 25 is driven and rotated, and the second feed shaft 17 is screwed together. The first feed shaft 16 is extended and the drive rotary shaft 3 is fed while being rotated. That is, a driving rotational force and a feeding force are applied to the driving rotary shaft 3 by driving a driving portion such as the electric motor or the engine.
[0020]
Next, a drilling method in the fluid transport pipe using the hole saw for the fluid transport pipe configured as described above will be described.
3-6 is an example of the to-be-processed body which faces the specific location in the fluid transport pipe P, and the gate valve B intervening in the middle of the fluid transport pipe P opening to the water storage pool C falls in the closed state and becomes inoperable. A drilling method in the case where the opening 27 for securing the flow path is drilled in the valve body b in the closed posture will be described.
First, as shown in FIG. 3, the connecting portion 6 formed on the bottom wall portion 2a of the cylindrical body 2 and the connecting flange portion 4A of the rotary transmission shaft 4 are fixedly connected by the bolts 5 of the fastening means, and then the fluid transport pipe. The cylindrical body 2 of the hole saw inserted from the opening end of P is rotated in a state where the shaft core correcting body 9 formed on the outer peripheral surface of the cylindrical body 2 is in contact with the inner peripheral surface of the fluid transport pipe P. A push operation is performed to a predetermined position in the fluid transport pipe P via the transmission shaft 4.
At this time, the shaft core correcting body 9 provided on the outer peripheral surface of the cylindrical body 2 comes into contact with the inner peripheral surface of the fluid transport pipe P, and the rotational shaft core of the cylindrical body 2 is used as the tube shaft core of the fluid transport pipe P. Even if the fluid transport pipe P can be corrected to the X side and the fluid transport pipe P is bent in a slightly U-shape at the place where the pipe joint D is interposed, the position of the rotational axis on the tip side of the cylindrical body 2 is It can be easily corrected by the swinging operation of the rotary transmission shaft 4 with the shaft core correcting body 9 in contact with the inner peripheral surface of the transport pipe P as a fulcrum.
[0021]
4 and 5, when the cylindrical body 2 reaches a predetermined position in the fluid transport pipe P, a connecting flange portion 4B formed at the base end portion of the rotary transmission shaft 4 and a perforation After the connecting flange 3A of the driving rotary shaft 3 of the machine A is fixedly connected with the bolt 5 of the fastening means, the driving portion of the drilling machine A is driven to apply the driving rotational force and the feeding force to the driving rotary shaft 3. In this way, the center drill 7 and the cylindrical body 2 make an opening 27 in the valve body (workpiece) b facing a specific location in the fluid transport pipe P.
[0022]
Further, when the center drill 7 starts drilling work on the valve body b of the gate valve B, the shaft center correcting body 9 substantially eliminates the need for the shaft center correcting action, and the shaft core correcting body 9 remains. In this case, under the drilling operation conditions in which the rotational axis of the cylindrical body 2 is slightly inclined with respect to the tube axis X of the fluid transport pipe P, the drilling operation by the cutting tip 1 of the cylindrical body 2 proceeds. Thus, there is a possibility that the shaft core correcting body 9 moving integrally with the cylindrical body 2 is gradually strongly pressed against the inner peripheral surface of the fluid transport pipe P, and the shaft core correcting body 9 may damage the inner peripheral surface of the fluid transport pipe P. There is. However, even if such a situation occurs, when the axial center correcting body 9 interferes (pressure contact) with the inner peripheral surface of the fluid transport pipe P and the resistance force (shearing force) increases beyond the set value, Since the shear pin 10 to which the shaft core correcting body 9 is attached is sheared and the entire shaft core correcting body 9 is separated from the cylindrical body 2, the inner peripheral surface of the fluid transport pipe P by the shaft core correcting body 2 is separated. Damage can be suppressed.
[0023]
The perforator A is mounted and fixed on a gantry E installed on the bottom surface of the water storage pool C, and the rotational axis position of the cylindrical body 2 is adjusted by a height adjusting means (not shown) of the gantry E. Is adjusted so that the rotational axis of the rotary transmission shaft 4 and the rotational axis of the driving rotary shaft 3 of the drilling machine A coincide with each other in a state where the fluid is corrected and maintained on the tube axis X side of the fluid transport pipe P.
[0024]
As shown in FIGS. 5 and 6, when the drilling process for the valve body b of the gate valve B is completed, the driving portion of the drilling machine A is stopped and the drive rotary shaft 3 and the rotary transmission shaft 4 are connected. Then, the center drill 7 and the cylindrical body 2 are manually pulled out and moved to the opening end side of the fluid transport pipe P. At this time, the section 11 that has entered the cylindrical body 2 is prevented from being pulled out by the retaining member 8 b of the retaining means 8, so that the section 11 is also collected together with the removal movement of the cylindrical body 2 and the center drill 7. can do.
[0025]
[Second Embodiment]
In the above-described first embodiment, when the shaft center correcting body 9 interferes (pressure contact) with the inner peripheral surface of the fluid transport pipe P and the resistance (shearing force) increases to a set value or more, the shaft core correcting body 9 The shear pin 10 to which the shaft 9 is attached is sheared so that the entire shaft core correcting body 9 is separated from the cylindrical body 2. However, as shown in FIG. 9A and a plurality of balls 9C are assembled between the inner ring 9B and the inner ring 9B is formed on the outer peripheral surface of the cylindrical body 2 on the bottom wall 2a side and the fluid. At the time of drilling the workpiece b facing a specific location in the transport pipe P, it adheres to a region not in contact with the workpiece b, so that the shaft core correcting body 9 interferes with the inner peripheral surface of the fluid transport pipe P (pressure contact). ) And when the resistance force (shearing force) increases to a set value or more, the shaft core correcting body 9 The outer ring 9A and the ball 9C corresponding to the tube contact portion of the shaft core correcting body 9 are separated from the cylindrical body 2 by breaking and disassembling between the outer ring 9A and the inner ring 9B of the rolling bearing. May be.
[0026]
Further, the rotating shaft core of the cylindrical body 2 is moved to the tube axis X side of the fluid transport pipe P by contact between the outer ring 9A of the rolling bearing constituting the shaft core correcting body 9 and the inner peripheral surface of the fluid transport pipe P. It is configured to correct.
In addition, since the other structure is the same as the structure demonstrated in 1st Embodiment, the same number is attached to the same structure location as 1st Embodiment, and the description is abbreviate | omitted.
[0027]
  [Other Embodiments]
  (1) In the above-mentioned embodiment, when the axial core straightening body 9 interferes with the inner peripheral surface of the fluid transport pipe P, the shearing or breaking occurs when the resistance force increases to a set value or more. 9 or a part including the tube contact portion is separated from the cylindrical body 2, but only the tube contact portion of the axial core correcting body 9 is separated from the cylindrical body 2. It may be configured.
  (2) In the above-described embodiment, the axis straightening body 9 is arranged on the outer peripheral surface on the base end side of the cylindrical body 2 and in the direction of the rotation axis in the region not in contact with the workpiece b during drilling. Although formed at a location, the axis correction body 9 is formed on the outer peripheral surface on the base end side of the cylindrical body 2 and at a plurality of locations in the direction of the rotation axis of the non-contact region with respect to the workpiece b. May be implemented.
  (3) In the above-described embodiment, the longitudinal cross-sectional shape along the tube axis direction of the axis correction body 9 is formed in a semicircular shape or a substantially semicircular shape. However, as shown in FIG. The longitudinal cross-sectional shape along the tube axis direction of the straightened body 9 may be configured to be a rounded triangular shape or the like. , Semi-elliptical shape, rounded trapezoidal shape, or similar shape to each of the aforementioned shapes.
[0028]
[Brief description of the drawings]
FIG. 1 is an enlarged longitudinal sectional view showing a first embodiment of a hole saw for a fluid transport pipe according to the present invention.
FIG. 2 is a sectional view of a drilling machine.
FIG. 3 is a process diagram showing a drilling method in a fluid transport pipe.
FIG. 4 is a process diagram showing a drilling method in a fluid transport pipe.
FIG. 5 is a process diagram showing a drilling method in a fluid transport pipe.
FIG. 6 is a process diagram showing a drilling method in a fluid transport pipe.
FIG. 7 is an enlarged longitudinal sectional view of a main part showing a second embodiment of a hole saw for a fluid transport pipe of the present invention.
FIG. 8 is an enlarged longitudinal sectional view of a main part showing a third embodiment of a hole saw for a fluid transport pipe of the present invention.
[Explanation of symbols]
A punching machine
b Workpiece
P Fluid transport pipe
X Tube core
1 Cutting tip
2 Cylindrical body
3 Drive rotation shaft
4 Rotating transmission shaft
7 Center drill
8 Stopping means
9 Axis core correction body
11 sections

Claims

A cutting tip is provided at the distal end portion of the cylindrical body, and a center drill that protrudes forward from the cutting tip is provided at the rotation center position of the base end portion in the cylindrical body. A hole saw provided with retaining means for preventing the section that has entered the cylindrical body from coming out ,
On the outer circumferential surface of the cylindrical body, by contact with the inner peripheral surface of the fluid transport pipe, axial straightening member is provided to correct the rotational axis of the cylindrical body to the pipe axis side of the fluid transport pipe, The shaft core correcting body is formed on the outer peripheral surface of the cylindrical body on the base end side, and in a region that does not come into contact with the workpiece when drilling the workpiece facing a specific location in the fluid transport pipe. ,
The shaft core straightening body is formed of a metal ring, and the shaft core straightening body and the peripheral wall portion of the cylindrical body opposed to each other in the radial direction are connected to each other in the fluid transport pipe. Caulking and fixing with a shear pin that is sheared or broken when the resistance force when interfering with the peripheral surface exceeds a set value, and at least the tube contact portion of the shaft core correction body is sheared by the shear pin and the cylindrical body Hole saw for fluid transport pipes configured to be separated from

The hole saw for fluid transport pipes according to claim 1, wherein the longitudinal cross-sectional shape along the tube axis direction of the axial core correction body is configured in a semicircular shape or a similar shape close thereto.

The longitudinal cross-sectional shape along the tube axis direction of the axial core correcting body with the shear pin for caulking and fixing the axial core correcting body as a boundary, the proximal end side of the cylindrical body is configured in a semicircular shape, and the distal end side is The hole saw for fluid transport pipes according to claim 1 , wherein the hole saw is configured to have a triangular shape with a diameter decreasing toward the tip side .

A cutting tip is provided at the distal end portion of the cylindrical body, and a center drill that protrudes forward from the cutting tip is provided at the rotation center position of the base end portion in the cylindrical body. A hole saw provided with retaining means for preventing the section that has entered the cylindrical body from coming out,
An axial core correction body is provided on the outer peripheral surface of the cylindrical body to correct the rotational axis of the cylindrical body to the tube axis side of the fluid transport pipe by contact with the inner peripheral surface of the fluid transport pipe.
The shaft core correcting body is composed of a rolling bearing in which a plurality of balls are assembled between an outer ring and an inner ring, and the inner ring is an outer peripheral surface on the base end side of the cylindrical body, and in the fluid transport pipe When the drilling of the workpiece facing the specific location is fixed to a region that does not come into contact with the workpiece, and the resistance force when the rolling bearing interferes with the inner peripheral surface of the fluid transport pipe increases beyond a set value The outer ring and the inner ring, and the outer ring and the ball corresponding to the tube contact portion of the shaft core correcting body are separated from the cylindrical body. Hole saw for pipes.

A drilling method using the hole saw for a fluid transport pipe according to any one of claims 1 to 4 , wherein the rotary transmission shaft to which the cylindrical body is attached is formed on an outer peripheral surface of the cylindrical body. When the cylindrical body reaches a predetermined position in the fluid transport pipe while the core straightening body is pressed from the opening end of the fluid transport pipe in a state of contacting the inner peripheral surface of the fluid transport pipe, the base end of the rotational transmission shaft The workpiece is fixedly connected to the driving rotary shaft of the drilling machine, and the driving rotary force and the feeding force are applied to the driving rotary shaft of the drilling machine, so that the workpiece facing the specific location in the fluid transport pipe is formed by the cylindrical body. A drilling method in a fluid transport pipe for drilling.