JP2004276054A

JP2004276054A - Friction stir welding method and equipment for the same

Info

Publication number: JP2004276054A
Application number: JP2003069073A
Authority: JP
Inventors: Masaharu Kojima; 正治小島; Koji Ezaki; 公二江崎; Junichi Kato; 純一加藤
Original assignee: Hitachi Industries Co Ltd
Current assignee: Hitachi Plant Technologies Ltd
Priority date: 2003-03-14
Filing date: 2003-03-14
Publication date: 2004-10-07
Anticipated expiration: 2023-03-14
Also published as: JP4147983B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a friction stir welding method capable of obtaining a junction of high quality by maintaining stable welding treatment without interrupting the welding treatment even when a foreign substance is placed on an abutting part of members desired to be welded in performing the welding treatment by pressing a tool under rotation to the members and causing the plastic fluidization of the welding members by the friction heat generated at this time. <P>SOLUTION: The welding treatment is continued while the control position of the joining tool 2 is kept maintained when the result of the measurement from a position sensor 6 disposed in a previous position of the joining tool 2 becomes outside the tolerance. The welding treatment is stopped in the case of the continuation of the state that the result of the measurement of the position sensor 6 is outside the tolerance a desired number of times. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、接合したい部材の衝合部に工具を回転させながら押し付けて発生する摩擦熱で、接合したい部材を塑性流動化させて固相での接合処理を行なう摩擦攪拌接合方法とその装置に関するものである。
【０００２】
【従来の技術】
摩擦攪拌接合は、突き合せたり重ね合せたりした２つの接合したい部材（以下、接合部材と略記）の接合個所（衝合部）に、接合部材より硬くて溶融温度の高い材料で製作した専用の工具（接合工具）を、回転させながら押し付けることによって発生する摩擦熱で接合部材を塑性流動化させ、接合工具を接合部材の中に接合深さまで挿入した後、衝合部に沿って回転させながら移動させて接合部材を接合する技術である（下記の特許文献１参照）。
【０００３】
接合部材は摩擦攪拌接合を行なう上で加工精度が低いので、接合工具を衝合部に沿って正確に移動させ、かつ接合部材上面の凹凸に合せて正確に移動させ、接合深さが一定になるように位置制御をしなければ、接合部に欠陥が発生したり接合深さにバラツキができたりして、接合部の強度が著しく低下してしまう。
【０００４】
摩擦攪拌接合を行なうためには接合工具と接合部材の高さ違いおよび衝合部とのズレ量を少なくするための位置制御技術を示すものとして、特許文献２などがある。
【０００５】
【特許文献１】
特表平７−５０５０９０号公報
【特許文献２】
特開２００２−１３７０７０号公報
【０００６】
【発明が解決しようとする課題】
従来の位置制御技術は、衝合部が水平に湾曲していたり凹んでいたりしている場合には接合深さを保持する上で都合のよいものであるが、衝合部上に異物が載っているような場合には、位置センサは異物表面を接合部材の表面位置と認識して、位置制御系では接合工具を異物に合せて引き上げるので、接合深さは浅くなって充分な接合強度を得られなくなるという問題があった。
【０００７】
また、異物に合せて接合工具の位置制御を頻繁に行なうと、接合している個所の温度と粘度を一定に維持できなくなり、安定した摩擦攪拌接合と接合部の品質安定を図ることも困難になる。
【０００８】
それゆえ本発明の目的は、衝合部上に異物が載っている場合でも所望の接合深さを維持できる摩擦攪拌接合方法とその装置を提供することにある。
【０００９】
また、本発明の目的は、衝合部上に異物が載っている場合でも接合処理を中断することがなく安定した接合処理を維持し高品品質の接合部を得ることができる摩擦攪拌接合方法とその装置を提供することにある。
【００１０】
【課題を解決するための手段】
上記の課題を解決する本発明摩擦攪拌接合方法の特徴とするところは、接合工具の先行位置に設けた接合したい部材の表面位置を計測する位置センサからの計測結果が許容範囲外となった場合には接合工具の制御位置を保持させたまま接合処理を継続し、位置センサの計測結果が許容範囲外であることが所望回数継続した場合には接合処理を停止させることにある。
【００１１】
また、上記の課題を解決する本発明摩擦攪拌接合装置の特徴とするところは、接合工具の先行位置に接合したい部材の表面位置を計測する位置センサを設け、この位置センサからの計測結果が許容範囲外となった場合には接合工具の制御位置を保持させたまま接合処理を継続し、位置センサの計測結果が許容範囲外であることが所望回数継続した場合には接合処理を停止させる制御手段を設けたことにある。
【００１２】
本発明は、接合部材上に乗っている異物は接合工具の回転で跳ね飛ばすことができること、および異物は接合部材での加工精度から許容される凹凸よりも大きいことが殆どで位置センサの計測結果から異物を判断することができることを見出したことに基づくものである。
【００１３】
【発明の実施の形態】
図１は、本発明になる摩擦攪拌接合方法を行なう本発明装置の概略構成を示している。
【００１４】
図１において、１ａ，１ｂは衝合部１ｃで接合をしたい接合部材で、図示を省略した保持テーブル上に着脱可能に固定してある。２は接合工具、３は接合工具２をトルクモータの主軸に設けたアタッチメント４で保持しθ方向の回転を与えるとともにＺ軸方向に位置制御を行なうＺ軸テーブルを内蔵した工具保持ヘッド、５は工具保持ヘッド３をＹ軸方向に移動し接合工具２の位置制御を行なうＹ軸テーブルである。Ｙ軸テーブル５は図示していないＸ軸テーブルでＸ軸方向に移動するようになっていて、ＸＹ両テーブルの所望方向への移動により、接合工具２は衝合部１ｃが延びるＸＹ各方向に自由に位置制御できる。６は工具保持ヘッド３にアタッチメント７でθ方向に回転し得るように固定した光学式の位置センサで、接合工具２の進行方向に先行して接合部材１ａ，１ｂの表面までの垂直距離により接合部材１ａ，１ｂの表面位置を計測し、衝合部１ｃの凹凸を観測するためのものである。８は接合工具２の回転数やＸＹＺ各方向への移動を制御するＮＣ装置（ＮＣ機械）、９は位置センサ６の計測結果からＮＣ装置８に動作指令を出すパソコンで構成した制御装置（制御手段）、１０は制御装置９のモニタ画面、１１はモニタ画面１０の表示を見ながら作業者が接合に関する各種データを入力するキーボードである。
【００１５】
制御装置９は、位置センサ６が衝合部１ｃを観測する結果に基づいて接合工具２をＸＹ各方向へ位置制御するソフトプログラムの他に衝合部１ｃ上に異物１２が載っている場合に異物１２であると認識して異物除去の処理を行なうソフトプログラムとこれらプログラムで得た判断結果とキーボード１１から入力された各種データとでＮＣ装置８が所望の接合処理を行なうための指令データを作る変換プログラムとモニタ画面１０で所望の表示をするためのソフトプログラムなどを有し、それらの処理に用いたデータを記憶しておく記憶部やデータの入出力処理を行なう入出力部などを備えている。
【００１６】
ＮＣ装置８はＸＹ各テーブル５や工具保持ヘッド３に制御信号を送るだけでなくこれらの動作状態を管理しており、管理状態は制御装置９に送って、制御装置９から管理状態に基づく指令を得るようになっている。
【００１７】
動作状態の管理に当たっては、接合工具２を回転させるトルクモータの駆動電力から計る接合工具２と接合部材１ａ，１ｂとの間に生じている摩擦力，ＸＹＺ各テーブルのエンコーダから得る接合工具２の位置データと工具保持ヘッド３がＺ軸方向への位置移動をして接合工具２を接合部材１ａ，１ｂに押し込んでいるトルクモータの駆動電力から計る押圧力，などに関する信号を入手している。接合工具２が回転して接合部材１ａ，１ｂとの間に生じている摩擦熱は、接合工具２が接合した直後の接合部１ｄの温度を計測することで入手できる。
【００１８】
接合部１ｄの温度は接合部１ｄにおける接合強度を確保する上で重要であり、温度が変動したら接合工具２の回転数や押し込み力あるいは接合部材１ａ，１ｂとの相対移動速度を制御し、できるだけ温度を一定に維持するようにする。
【００１９】
これらの諸データは接合部材１ａ，１ｂの材質や衝合部の形状や接合深さなどに応じて、予め設計値をキーボードを介して制御装置９に初期設定しておき、制御装置９は各部から送られてくる信号と設計値を比較して、摩擦攪拌接合における全ての制御を行なうようになっている。
【００２０】
以下に摩擦攪拌接合を行なうための本発明になる異物検知を含めた接合工具の位置制御について説明する。
【００２１】
先ず、図２により接合工具２が摩擦攪拌接合を行なうために位置センサ６で接合部材１ａ，１ｂの表面を計測する状況を説明する。
【００２２】
図２（ａ），（ｂ）は位置センサ６で得た接合部材１ａ，１ｂにおける表面の高さを図１のＹ方向位置とＸ方向位置で示している。接合部材１ａ，１ｂの表面は突出していてその突出部で衝合しており、位置センサ６はこの突出部を含んで１段低い領域まで、表面位置を観測している。表面位置は前以て分かっているから、この段差は表面形状と判断し、異物とは認知しないようにしてある。また、衝合部では加工精度に基づく隙間があれば、突然表面位置が低くなるが、段差部から衝合部までの距離も加工精度に基づく許容範囲が前以て分かっているから、隙間が存在していると判断するようにしてある。
【００２３】
初期設定された接合部材１ａ，１ｂにおける表面の高さは設定値Ｚ０で示し、異物１２の高さをΔＺで示している。工具直径は接合工具２の直径で、図１に示すように衝合部１ｃに沿ったＸ軸方向に接合工具２が移動し、異物１２は衝合部１ｃ上で工具直径の範囲にあると仮定する。
【００２４】
位置センサ６はＹ軸方向に高速に表面の高さを計測しつつ、接合工具２とともにゆっくりＸ軸方向に移動していく。この場合、位置センサ６による計測は、Ｘ軸方向に所望の間隔（例えば、３ｍｍの間隔）を置いて計測をする。位置センサ６の計測結果が接合部材１ａ，１ｂに加工精度から許容された範囲の凹凸（例えば、０．５ｍｍ）内であれば、位置センサ６が計測した位置に接合工具が位置するときに、接合工具２は計測結果に合せて工具保持ヘッド３に内蔵のＺ軸テーブルで上下方向に位置制御が行なわれる。殆どの場合、異物１２は高さΔＺが接合部材１ａ，１ｂに加工精度から許容された凹凸の範囲（許容範囲）よりも大きい。
【００２５】
次ぎに図３により、接合工具２の位置制御について説明する。
先ず、ステップ（以下、Ｓと略記）１００で既に説明した接合処理に必要な各種データの初期設定をモニタ画面１０の表示を参照しつつキーボード１１から行なう。その後、Ｓ２００でＸＹＺ各軸テーブルにより位置センサ６を接合工具２による摩擦攪拌接合の始点（開始位置）に移動させる。
【００２６】
そして、Ｓ３００で位置センサ６による計測を行ない、Ｓ４００で計測結果から得た接合部材１ａ，１ｂにおける表面の凹凸が許容範囲内かどうか判断する。
【００２７】
接合部材１ａ，１ｂにおける表面の凹凸が０．３ｍｍであれば、許容範囲の０．５ｍｍ内であるので、Ｓ５００に進んで、位置調節の指令値を作り、接合工具２が表面凹凸０．３ｍｍを計測した位置センサ６の位置に達したときに位置制御ができるようにしておき、Ｓ６００でその指令値に従った位置制御をして接合処理を行なう。そしてＳ７００で計測位置が接合処理の終点に到っているか判断して、到っていなければ，Ｓ３００に戻って、以上の処理を繰り返す。
【００２８】
Ｓ４００で接合部材１ａ，１ｂにおける表面の凹凸が１．３ｍｍであれば、許容範囲（０．５ｍｍ）内ではないので、Ｓ８００に進んで許容範囲（０．５ｍｍ）を越えた回数を確認する。越えた回数が所望回数（例えば４回目）以内であれば、異物であると予想してそのままＳ６００に進んで接合処理を続けるようにする。これは、１．５ｍｍの計測をしたものが異物であれば、異物は接合部材１ａ，１ｂ上に載っているだけで接合工具２が当接したときに接合工具２によって跳ね飛ばしたり押し除けることができ、Ｓ７００からＳ３００に戻って再び計測をした場合、異物１２が排除されて無ければ、位置センサ６は接合部材１ａ，１ｂの表面位置を計測することになり、徒に位置制御をしなくてもよいからである。
【００２９】
しかしながら、Ｓ７００からＳ３００に戻って再び計測をした場合、許容範囲（０．５ｍｍ）を越えた回数が５回も重なれば、その長さは計測間隔４回分（３ｍｍ×４）は越えた大きさを持っており、異物１２と予想してしまうのはあまりに大きいので、Ｓ９００に進んで一旦装置を止めて、作業者が接合部材１ａ，１ｂ上を確認し、原因となっている案件を手作業で除去し、再開の修正処理をしてからＳ６００に進んで、以上の処理を繰り返す。
【００３０】
Ｓ７００で計測位置が接合の終点であれば、接合工具２が終点にきた時期を見計らって終了とする。
【００３１】
なお、Ｓ８００からＳ９００に進んで装置を停止させる場合、非常灯を点灯させたり警報を発したりするようにしておけば、作業者は装置から離れて他の作業に従事することができる。
【００３２】
また、図２（ａ）に工具直径で示す設定値から接合工具２の接合範囲から横に外れた位置に異物１２があることも確認でき、そのようなときは接合工具２は異物１２に接触しないし、接合そのものの障害にもならないので、Ｓ４００の判断は接合工具２の接合範囲内に異物１２が存在している場合に限るようにしても良い。
【００３３】
さらに、衝合部１ｃのＹ方向での隙間は加工精度の許容範囲内にあることが殆どであるが、位置センサ６による計測の結果、設定値Ｚ０を持たないＹ方向での幅が衝合部１ｃのＹ方向での隙間に関する加工精度許容範囲外であれば、そのような個所について接合処理をすると、周辺の接合部材が塑性流動で隙間を埋める結果、接合部１ｄの表面位置が下がってしまい、所望の接合強度を得られないことがあるので、そのような時も異物１２は存在していないがＳ８００からＳ９００に進むようにしておくと良い。
【００３４】
【発明の効果】
以上説明したように本発明によれば、衝合部上に異物が載っている場合でも所望の接合深さを維持できる。
【００３５】
さらに本発明によれば衝合部上に異物が載っている場合でも接合処理を中断することがなく安定した接合処理を維持し高品品質の接合部を得ることができる
【図面の簡単な説明】
【図１】本発明になる摩擦攪拌接合を行なう摩擦攪拌接合装置の概略構成を示す図である。
【図２】位置センサで計測した接合部材の表面位置を示す図である。
【図３】図１に示した摩擦攪拌接合装置において行なう接合工具位置制御のフロー図である。
【符号の説明】
１ａ，１ｂ…接合部材
１ｃ…衝合部
１ｄ…接合部
２…接合工具
５…Ｙ軸テーブル
６… 位置センサ
８…ＮＣ装置
９…制御装置
１０…モニタ画面[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a friction stir welding method and a friction stir welding method in which a member to be joined is plastically fluidized by frictional heat generated by pressing a rotating tool against an abutting portion of a member to be joined to perform joining processing in a solid phase. Things.
[0002]
[Prior art]
Friction stir welding is a special-purpose joint made of a material that is harder than the joining member and has a high melting temperature, at the joining point (abutting portion) of two joined but-to-be-joined members (hereinafter, simply referred to as joining members). A tool (joining tool) is plastically fluidized by frictional heat generated by pressing while rotating, and after inserting the joining tool to the joining depth into the joining member, rotating along the abutting portion This is a technique of joining the joining members by moving them (see Patent Document 1 below).
[0003]
Since the joining members have low processing accuracy in performing friction stir welding, the joining tool is moved accurately along the abutment part, and precisely moved according to the unevenness on the upper surface of the joining member, so that the joining depth is constant If the position is not controlled so as to be as follows, a defect occurs in the joint portion or the joining depth varies, so that the strength of the joint portion is significantly reduced.
[0004]
Patent Document 2 and the like show a position control technique for reducing the difference in height between a welding tool and a welding member and the amount of displacement between the abutting portions in order to perform friction stir welding.
[0005]
[Patent Document 1]
Japanese Patent Publication No. 7-5050590 [Patent Document 2]
JP, 2002-137070, A
[Problems to be solved by the invention]
Conventional position control technology is convenient for maintaining the joining depth when the abutting portion is curved or depressed horizontally.However, when foreign matter is placed on the abutting portion, In such a case, the position sensor recognizes the surface of the foreign matter as the surface position of the joining member, and the position control system raises the joining tool according to the foreign matter, so that the joining depth becomes shallow and sufficient joining strength is obtained. There was a problem that it could not be obtained.
[0007]
In addition, if the position of the welding tool is frequently controlled according to the foreign matter, the temperature and viscosity of the welding point cannot be maintained at a constant level, making it difficult to achieve stable friction stir welding and stable quality of the joint. Become.
[0008]
Therefore, an object of the present invention is to provide a friction stir welding method and apparatus capable of maintaining a desired welding depth even when foreign matter is placed on the abutting portion.
[0009]
Further, an object of the present invention is to provide a friction stir welding method capable of maintaining a stable joining process without interrupting the joining process even when foreign matter is placed on the abutting portion and obtaining a high quality joining portion. And to provide the device.
[0010]
[Means for Solving the Problems]
The feature of the friction stir welding method of the present invention that solves the above problem is that the measurement result from the position sensor that measures the surface position of the member to be welded provided at the preceding position of the welding tool is out of the allowable range. Is to continue the joining process while holding the control position of the joining tool, and to stop the joining process if the measurement result of the position sensor is out of the allowable range for a desired number of times.
[0011]
Another feature of the friction stir welding apparatus of the present invention that solves the above problems is that a position sensor for measuring a surface position of a member to be welded is provided at a preceding position of a welding tool, and a measurement result from this position sensor is allowed. If it is out of the range, the welding process is continued while holding the control position of the welding tool, and if the measurement result of the position sensor is out of the allowable range for the desired number of times, the welding process is stopped. The means have been provided.
[0012]
According to the present invention, the foreign matter on the joining member can be bounced off by the rotation of the joining tool, and the foreign matter is generally larger than the unevenness allowed from the processing accuracy of the joining member. This is based on the finding that it is possible to judge a foreign substance from the object.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a schematic configuration of an apparatus of the present invention for performing the friction stir welding method according to the present invention.
[0014]
In FIG. 1, reference numerals 1a and 1b denote joining members to be joined at the abutment portion 1c, which are detachably fixed on a holding table (not shown). 2 is a welding tool, 3 is a tool holding head having a built-in Z-axis table that holds the welding tool 2 with an attachment 4 provided on a main shaft of a torque motor, gives rotation in the θ direction, and performs position control in the Z-axis direction. 4 is a Y-axis table that moves the tool holding head 3 in the Y-axis direction and controls the position of the welding tool 2. The Y-axis table 5 is configured to move in the X-axis direction by an X-axis table (not shown), and the joining tool 2 moves in the XY directions in which the abutment portion 1c extends by moving the XY tables in desired directions. Position can be controlled freely. Reference numeral 6 denotes an optical position sensor fixed to the tool holding head 3 so as to be rotatable in the θ direction with an attachment 7. The optical position sensor is joined by a vertical distance to the surfaces of the joining members 1 a and 1 b prior to the traveling direction of the joining tool 2. This is for measuring the surface positions of the members 1a and 1b and observing the unevenness of the abutting portion 1c. Reference numeral 8 denotes an NC device (NC machine) for controlling the rotational speed of the welding tool 2 and movement in each of the XYZ directions, and reference numeral 9 denotes a control device (control device) constituted by a personal computer which issues an operation command to the NC device 8 based on the measurement result of the position sensor 6. Means) 10 is a monitor screen of the control device 9, and 11 is a keyboard by which an operator inputs various data relating to joining while watching the display on the monitor screen 10.
[0015]
The control device 9 controls the position of the welding tool 2 in the X and Y directions based on the result of the position sensor 6 observing the abutting portion 1c, and also controls the position of the foreign object 12 on the abutting portion 1c in addition to the software program. The software program for recognizing the foreign matter 12 and performing the foreign matter removal processing, the determination result obtained by these programs, and various data input from the keyboard 11 provide command data for the NC device 8 to perform the desired joining processing. It has a conversion program to be created, a software program for performing a desired display on the monitor screen 10, and the like, and has a storage unit for storing data used for the processing, an input / output unit for performing data input / output processing, and the like. ing.
[0016]
The NC device 8 not only sends control signals to the XY tables 5 and the tool holding head 3 but also manages the operation states thereof. The management state is sent to the control device 9, and a command based on the management state is sent from the control device 9. Is to be obtained.
[0017]
In managing the operation state, the frictional force generated between the joining tool 2 and the joining members 1a and 1b measured from the driving power of the torque motor for rotating the joining tool 2 and the joining tool 2 obtained from the encoders of the XYZ tables are used. The position data and the signal relating to the pressing force measured from the driving power of the torque motor for pushing the joining tool 2 into the joining members 1a and 1b by moving the position of the tool holding head 3 in the Z-axis direction to obtain the joining tool 2 are obtained. The frictional heat generated between the joining tool 2 and the joining members 1a and 1b due to the rotation of the joining tool 2 can be obtained by measuring the temperature of the joining portion 1d immediately after the joining tool 2 has joined.
[0018]
The temperature of the joining portion 1d is important for securing the joining strength at the joining portion 1d. When the temperature fluctuates, the rotation speed and the pushing force of the joining tool 2 or the relative moving speed with the joining members 1a and 1b are controlled. Try to keep the temperature constant.
[0019]
These data are initially set in the controller 9 via a keyboard in advance according to the material of the joining members 1a and 1b, the shape of the abutting portion, the joining depth, and the like. A comparison is made between a signal sent from the controller and a design value, and all controls in friction stir welding are performed.
[0020]
Hereinafter, the position control of the welding tool including the foreign object detection according to the present invention for performing the friction stir welding will be described.
[0021]
First, a situation in which the position sensor 6 measures the surfaces of the joining members 1a and 1b so that the joining tool 2 performs friction stir welding will be described with reference to FIG.
[0022]
FIGS. 2A and 2B show the heights of the surfaces of the joining members 1a and 1b obtained by the position sensor 6 in the Y-direction position and the X-direction position in FIG. The surfaces of the joining members 1a and 1b protrude and abut against each other at the protruding portions, and the position sensor 6 observes the surface position up to an area one step lower including the protruding portions. Since the surface position is known in advance, this step is determined to be the surface shape and is not recognized as a foreign substance. Also, if there is a gap based on the processing accuracy at the abutment part, the surface position suddenly drops, but since the allowable range based on the processing accuracy is also known in advance for the distance from the step part to the abutment part, the gap is It is determined that it exists.
[0023]
The initially set surface heights of the joining members 1a and 1b are indicated by a set value Z0, and the height of the foreign matter 12 is indicated by ΔZ. The tool diameter is the diameter of the joining tool 2, and as shown in FIG. 1, when the joining tool 2 moves in the X-axis direction along the abutting portion 1c, the foreign matter 12 is within the range of the tool diameter on the abutting portion 1c. Assume.
[0024]
The position sensor 6 slowly moves in the X-axis direction together with the welding tool 2 while measuring the surface height at a high speed in the Y-axis direction. In this case, the measurement by the position sensor 6 is performed at a desired interval (for example, an interval of 3 mm) in the X-axis direction. If the measurement result of the position sensor 6 is within the unevenness (for example, 0.5 mm) in the range allowed for the processing accuracy of the joining members 1a and 1b, when the joining tool is located at the position measured by the position sensor 6, The position of the welding tool 2 is controlled in the vertical direction by a Z-axis table built in the tool holding head 3 in accordance with the measurement result. In most cases, the height ΔZ of the foreign matter 12 is larger than the range (permissible range) of the unevenness allowed for the joining members 1a and 1b from the processing accuracy.
[0025]
Next, position control of the welding tool 2 will be described with reference to FIG.
First, initial settings of various data necessary for the joining process already described in step (hereinafter abbreviated as S) 100 are performed from the keyboard 11 while referring to the display on the monitor screen 10. Thereafter, in S200, the position sensor 6 is moved to the start point (start position) of the friction stir welding by the welding tool 2 using the XYZ axis tables.
[0026]
Then, measurement is performed by the position sensor 6 in S300, and it is determined in S400 whether the unevenness of the surface of the joining members 1a and 1b obtained from the measurement result is within an allowable range.
[0027]
If the unevenness of the surface of the joining members 1a and 1b is 0.3 mm, it is within the allowable range of 0.5 mm. When the position of the position sensor 6 is measured, position control can be performed, and in S600, position control is performed according to the command value to perform the joining process. Then, in S700, it is determined whether the measurement position has reached the end point of the joining process. If not, the process returns to S300, and the above process is repeated.
[0028]
If the unevenness of the surfaces of the joining members 1a and 1b is 1.3 mm in S400, it is not within the allowable range (0.5 mm), so the process proceeds to S800 and the number of times exceeding the allowable range (0.5 mm) is checked. If the number of times exceeds the desired number (for example, the fourth time), the process proceeds to S600 as it is, assuming that it is a foreign substance, and the joining process is continued. This means that if the object measured at 1.5 mm is a foreign substance, the foreign substance is merely placed on the joining members 1a and 1b, and when the joining tool 2 comes into contact with the foreign object, the foreign object is bounced off or pushed away. When the measurement is returned again from S700 to S300, if the foreign matter 12 is not removed, the position sensor 6 measures the surface positions of the joining members 1a and 1b, and the position control is not performed. Because it may be.
[0029]
However, when the measurement is returned again from S700 to S300 and the number of times exceeding the allowable range (0.5 mm) overlaps five times, the length exceeds the measurement interval four times (3 mm × 4). Since it is too large to predict that the foreign matter 12 is present, the process proceeds to S900, in which the apparatus is temporarily stopped, and the worker checks the joining members 1a and 1b to manually determine the cause of the problem. After removing it by the work and performing the resumption correction processing, the process proceeds to S600, and the above processing is repeated.
[0030]
If the measurement position is the end point of the welding in S700, the timing is determined when the welding tool 2 reaches the end point.
[0031]
When the apparatus is stopped from S800 to S900, if the emergency light is turned on or an alarm is issued, the worker can leave the apparatus and engage in other work.
[0032]
In addition, it can be confirmed from the set value indicated by the tool diameter in FIG. 2A that there is a foreign matter 12 at a position laterally out of the welding range of the welding tool 2. In such a case, the welding tool 2 contacts the foreign matter 12. In addition, since it does not cause an obstacle to the welding itself, the determination in S400 may be limited to the case where the foreign matter 12 exists in the welding area of the welding tool 2.
[0033]
In addition, the gap in the Y direction of the abutment portion 1c is mostly within the allowable range of the processing accuracy, but as a result of the measurement by the position sensor 6, the width in the Y direction having no set value Z0 If the processing accuracy for the gap in the Y direction of the portion 1c is out of the permissible range, the joining process is performed at such a portion, and the surrounding joining members fill the gap with plastic flow, so that the surface position of the joining portion 1d is lowered. In such a case, a desired bonding strength may not be obtained. Therefore, in such a case, the foreign matter 12 does not exist, but it is preferable to proceed from S800 to S900.
[0034]
【The invention's effect】
As described above, according to the present invention, a desired bonding depth can be maintained even when a foreign substance is placed on the abutting portion.
[0035]
Further, according to the present invention, even when a foreign substance is placed on the abutting portion, it is possible to maintain a stable joining process without interrupting the joining process and to obtain a high quality joining portion. ]
FIG. 1 is a diagram showing a schematic configuration of a friction stir welding apparatus for performing friction stir welding according to the present invention.
FIG. 2 is a diagram illustrating a surface position of a bonding member measured by a position sensor.
FIG. 3 is a flowchart of welding tool position control performed in the friction stir welding apparatus shown in FIG. 1;
[Explanation of symbols]
1a, 1b joining member 1c joining portion 1d joining portion 2 joining tool 5 Y-axis table 6 position sensor 8 NC device 9 control device 10 monitor screen

Claims

接合したい部材の衝合部に工具を回転させながら押し付けて発生する摩擦熱で該接合したい部材を塑性流動化させて接合処理を行なう摩擦攪拌接合方法において、
該工具の先行位置に設けた接合したい部材の表面位置を計測する位置センサからの計測結果が許容範囲外となった場合には該工具の制御位置を保持させたまま接合処理を継続し、該位置センサの計測結果が許容範囲外であることが所望回数継続した場合には該接合処理を停止させることを特徴とする摩擦攪拌接合方法。In a friction stir welding method in which the member to be joined is plastically fluidized by frictional heat generated by pressing the tool while rotating the abutting portion of the member to be joined and the joining process is performed,
If the measurement result from the position sensor that measures the surface position of the member to be joined provided at the preceding position of the tool is out of the allowable range, the joining process is continued while holding the control position of the tool, A friction stir welding method, wherein the welding process is stopped when the measurement result of the position sensor is out of an allowable range for a desired number of times.

上記請求項１において、該位置センサからの計測結果が許容範囲内である場合には該工具の位置制御を行なうことを特徴とする摩擦攪拌接合方法。2. The friction stir welding method according to claim 1, wherein the position of the tool is controlled when the measurement result from the position sensor is within an allowable range.

接合したい部材の衝合部に工具を回転させながら押し付けて発生する摩擦熱で該接合したい部材を塑性流動化させて接合処理を行なう摩擦攪拌接合装置において、
該工具の先行位置に接合したい部材の表面位置を計測する位置センサを設け、該位置センサからの計測結果が許容範囲外となった場合には該工具の制御位置を保持させたまま接合処理を継続し、該位置センサの計測結果が許容範囲外であることが所望回数継続した場合には該接合処理を停止させる制御手段を設けたことを特徴とする摩擦攪拌接合装置。In a friction stir welding apparatus that performs a joining process by plastically fluidizing the member to be joined with frictional heat generated by pressing a tool while rotating the abutting portion of the member to be joined,
A position sensor for measuring a surface position of a member to be joined at a preceding position of the tool is provided, and when a measurement result from the position sensor is out of an allowable range, joining processing is performed while holding a control position of the tool. A friction stir welding apparatus characterized by further comprising control means for stopping the welding process when the measurement result of the position sensor is out of an allowable range for a desired number of times.

上記請求項３において、該衝合部に該工具を回転させながら押し付け該衝合部に沿って該工具と該位置センサを一緒に移動させるＮＣ機械が該制御手段の指令に基づいて動作するようになされていることを特徴とする摩擦攪拌接合装置。The NC machine according to claim 3, wherein the NC machine for rotating the tool against the abutting portion while rotating the tool and moving the tool and the position sensor together along the abutting portion operates based on a command from the control means. A friction stir welding apparatus characterized in that:

上記請求項３において、該位置センサは接合したい部材の表面位置までの距離を計測するものであることを特徴とする摩擦攪拌接合装置。4. The friction stir welding apparatus according to claim 3, wherein the position sensor measures a distance to a surface position of a member to be welded.