JP2009184071A

JP2009184071A - Wire electric discharge processing device and wire breakage detecting method

Info

Publication number: JP2009184071A
Application number: JP2008026678A
Authority: JP
Inventors: Hidetaka Miyake; 英孝三宅; Tatsushi Sato; 達志佐藤; Takayuki Nakagawa; 孝幸中川; Yasuo Onodera; 康雄小野寺; Tomoko Sendai; 知子千代; Takaaki Iwata; 高明岩田
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2008-02-06
Filing date: 2008-02-06
Publication date: 2009-08-20
Anticipated expiration: 2028-02-06
Also published as: JP4948441B2

Abstract

<P>PROBLEM TO BE SOLVED: To rapidly detect breakage of an electrode wire; and to rapidly stop a wire electric discharge processing device. <P>SOLUTION: The wire electric discharge processing device includes the electrode wire 2 for generating electric discharge between a workpiece 8 and it, a processing power source 6 for applying a pulsating processing voltage between the electrode wire 2 and the workpiece 8, a breakage detecting power source 11 for applying a voltage for detecting breakage on both ends of the electrode wire 2, and a breakage detecting power source control means 12 for controlling timing of application by the breakage detecting power source 11, and detects breakage based on a conduction state of the electrode wire 2 when the voltage for detecting the breakage is applied. The voltage for detecting the breakage is applied only in a period when the voltage by the processing power source 6 is not applied. Thus, the breakage is detected, and the wire electric discharge processing device is rapidly stopped, and thereby, entanglement of the electric wire 2 with surroundings caused by the breakage can be prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明はワイヤ放電加工装置およびワイヤ断線検出方法に関し、特に、ワイヤ状の工具電極と被加工物との間に放電を発生させることにより、被加工物の一部を除去しながら被加工物を加工するワイヤ放電加工装置およびワイヤ断線検出方法に関するものである。 The present invention relates to a wire electric discharge machining apparatus and a wire breakage detection method, and in particular, by generating an electric discharge between a wire-shaped tool electrode and a workpiece, the workpiece is removed while removing a part of the workpiece. The present invention relates to a wire electric discharge machining apparatus and a wire breakage detection method.

ワイヤ放電加工装置により、柱状の部材等の被加工物から薄板をスライス加工する場合、１本の電極ワイヤを複数のガイドローラー間に巻回させて多数の切断ワイヤ部分を形成し、それぞれの切断ワイヤ部分に個別に給電し、各切断ワイヤ部分と被加工物の加工面との間のギャップ長、すなわち、放電ギャップ長を所定の値に保持することにより、各切断ワイヤ部分と被加工物の加工面との間に同時に放電を生ぜしめて、被加工物に対する上記スライス加工の生産性を向上させる試みが提案されている（例えば、特許文献１参照）。 When slicing a thin plate from a workpiece such as a columnar member with a wire electrical discharge machining device, a single electrode wire is wound between a plurality of guide rollers to form a large number of cutting wire portions, each of which is cut By individually supplying power to the wire portions and maintaining the gap length between each cutting wire portion and the work surface of the workpiece, that is, the discharge gap length, at a predetermined value, There has been proposed an attempt to improve the productivity of the above-described slicing process on a workpiece by simultaneously generating electric discharge between the processed surface and the processed surface (for example, see Patent Document 1).

また、上述のようなワイヤ放電加工装置における電極ワイヤの断線検出については、加工電源の電圧を分圧して給電子間の電圧変動を検出する方法が知られている（例えば、特許文献２参照）。当該方法では、電極ワイヤが断線すると給電子間の電圧が著しく高くなることを利用して、当該電圧が基準値以上になったときに、電極ワイヤが断線状態にあると検知して、加工電源を遮断する信号を出力する。 As for the detection of the disconnection of the electrode wire in the wire electric discharge machining apparatus as described above, a method is known in which the voltage of the machining power supply is divided to detect the voltage fluctuation between the supply electrons (for example, see Patent Document 2). . In this method, by utilizing the fact that the voltage between the feeders is remarkably increased when the electrode wire is disconnected, it is detected that the electrode wire is in a disconnected state when the voltage exceeds a reference value, and the processing power supply A signal that shuts off is output.

特開２０００−９４２２１号公報JP 2000-94221 A 特開平４−３６５５１５号公報JP-A-4-365515

前述の特許文献１に記載の従来のワイヤ放電加工装置にあっては、すべての切断ワイヤ部分は元々１本の電極ワイヤからなるものであるから、加工中に電極ワイヤが断線すると、その断線した電極ワイヤが対向していた部分では以後の加工ができなくなり生産性を低下させるという問題点があった。さらに、電極ワイヤが断線したことを即座に検出しないと、電極ワイヤの断線した部分を起点として、電極ワイヤがガイドローラーからほぐれ、周囲のガイドローラーと電極ワイヤとの間に絡まってしまう可能性がある。その状態となると、以後の加工継続が不可能なのはもちろんのこと、絡まった電極ワイヤを取り除いて、再加工を始めるまでの復旧作業に手間取るという問題点があった。 In the conventional wire electric discharge machining apparatus described in the above-mentioned Patent Document 1, since all the cutting wire portions are originally composed of one electrode wire, if the electrode wire is broken during machining, the wire breaks. There is a problem in that the portion where the electrode wires face each other cannot be processed thereafter and the productivity is lowered. Furthermore, if it is not immediately detected that the electrode wire is disconnected, the electrode wire may be loosened from the guide roller starting from the disconnected portion of the electrode wire, and may be entangled between the surrounding guide roller and the electrode wire. is there. In this state, there is a problem that it is not possible to continue processing thereafter, and that it takes time to perform recovery work until the tangled electrode wire is removed and reworking is started.

また、電極ワイヤの断線検出については、特許文献２の方法により検出を行う場合、特許文献２に記載のように、給電子が２個の場合には良好に検出を行うことができるが、特許文献１に記載のようなワイヤが複数本張られたワイヤ放電加工装置の場合には、同時に各給電子間の電圧変動を検出することができず、切り換えて、順に検出していくしかないので、ワイヤ断線検出を効率よく安定させて行うことができないという問題点があった。また、特許文献２の検出方法において、各給電子間の電圧の変動を検出するためには、各給電子間に対して比較増幅器を２個ずつ設ける必要があり、回路が複雑になってしまうという問題点があった。 As for the detection of the disconnection of the electrode wire, when the detection is performed by the method of Patent Document 2, as described in Patent Document 2, the detection can be performed satisfactorily when the number of supplied electrons is two. In the case of a wire electric discharge machining apparatus in which a plurality of wires are stretched as described in Document 1, voltage fluctuations between the respective power supply electrons cannot be detected at the same time, but they must be switched and detected sequentially. There is a problem that wire breakage detection cannot be performed efficiently and stably. In addition, in the detection method disclosed in Patent Document 2, in order to detect voltage fluctuations between the power supply units, it is necessary to provide two comparison amplifiers between the power supply units, which complicates the circuit. There was a problem.

本発明は、かかる問題点を解決するためになされたものであり、電極ワイヤの断線を迅速に検出して、その検出信号によりワイヤ放電加工装置を即座に停止させることが可能なワイヤ放電加工装置およびワイヤ断線検出方法を得ることを目的としている。 The present invention has been made to solve such a problem, and is capable of quickly detecting a disconnection of an electrode wire and immediately stopping the wire electrical discharge machining apparatus by the detection signal. And it aims at obtaining the wire breakage detection method.

この発明は、被加工物との間で放電を発生する電極ワイヤと、前記電極ワイヤと前記被加工物との間にパルス状の加工用の電圧を印加する加工用電源と、前記電極ワイヤの両端に断線検知用の電圧を印加する断線検知用電源と、前記断線検知用電源による前記印加のタイミングを制御する断線検知用電源制御手段と、前記断線検知用電源により前記断線検知用の電圧を印加したときの前記電極ワイヤの導通状態に基づいて、前記電極ワイヤの断線の有無を検知する断線検出手段とを備え、前記断線検知用電源制御手段は、前記加工用電源によってパルス状の前記加工用の電圧が印加されていない期間のみに、前記断線検知用の電圧を印加するように、前記タイミングの制御を行うことを特徴とするワイヤ放電加工装置である。 The present invention includes an electrode wire that generates an electric discharge between a workpiece, a machining power source that applies a pulsed machining voltage between the electrode wire and the workpiece, and the electrode wire A disconnection detection power source for applying a disconnection detection voltage to both ends, a disconnection detection power source control means for controlling the timing of the application by the disconnection detection power source, and the disconnection detection voltage by the disconnection detection power source. A disconnection detecting means for detecting the presence or absence of disconnection of the electrode wire based on the conduction state of the electrode wire when applied, and the disconnection detection power control means is pulsated by the processing power supply. The wire electric discharge machining apparatus is characterized in that the timing is controlled so that the disconnection detection voltage is applied only during a period in which no voltage is applied.

この発明は、被加工物との間で放電を発生する電極ワイヤと、前記電極ワイヤと前記被加工物との間にパルス状の加工用の電圧を印加する加工用電源と、前記電極ワイヤの両端に断線検知用の電圧を印加する断線検知用電源と、前記断線検知用電源による前記印加のタイミングを制御する断線検知用電源制御手段と、前記断線検知用電源により前記断線検知用の電圧を印加したときの前記電極ワイヤの導通状態に基づいて、前記電極ワイヤの断線の有無を検知する断線検出手段とを備え、前記断線検知用電源制御手段は、前記加工用電源によってパルス状の前記加工用の電圧が印加されていない期間のみに、前記断線検知用の電圧を印加するように、前記タイミングの制御を行うことを特徴とするワイヤ放電加工装置であるので、電極ワイヤの断線を迅速に検出することができ、断線を検出した場合には、その検出信号によりワイヤ放電加工装置を即座に停止させることが可能である。 The present invention includes an electrode wire that generates an electric discharge between a workpiece, a machining power source that applies a pulsed machining voltage between the electrode wire and the workpiece, and the electrode wire A disconnection detection power source for applying a disconnection detection voltage to both ends, a disconnection detection power source control means for controlling the timing of the application by the disconnection detection power source, and the disconnection detection voltage by the disconnection detection power source. A disconnection detecting means for detecting the presence or absence of disconnection of the electrode wire based on the conduction state of the electrode wire when applied, and the disconnection detection power control means is pulsated by the processing power supply. Since the wire electric discharge machining apparatus controls the timing so as to apply the disconnection detection voltage only during a period in which no voltage is applied, the electrode wire Can be quickly detected disconnection, when detecting a disconnection, it is possible to stop immediately the wire electric discharge machining apparatus by the detection signal.

実施の形態１．
以下に、本発明の実施の形態の構成および動作について説明する。
図１は、本発明の実施の形態１に係るワイヤ放電加工装置を示した斜視図である。本実施の形態１に係るワイヤ放電加工装置においては、ワイヤボビン１から繰り出された一本の電極ワイヤ２が、順次、複数のガイドローラー３ａ〜３ｆ間を、複数回、互いに微小な間隔を隔てて巻回されて、複数のワイヤ走行系が形成されている。この電極ワイヤ２が巻回されて形成されたワイヤ走行系間の間隔が被加工物８の加工幅に対応する。すなわち、各ワイヤ走行系に対して所定間隔だけ離間させて被加工物を対向させて配置した状態で、各ワイヤ走行系と被加工物８との間に電圧を印加しながら、被加工物８を各ワイヤ走行系に対して切断送りすることにより、被加工物８を各ワイヤ走行系で放電切断する。これにより、柱状の被加工物８が薄板にスライス加工される。なお、図１の例では、１本の電極ワイヤ２を複数のガイドローラーに巻き回した例について示しているが、この場合に限らず、１本の電極ワイヤ２を折り返すことにより複数のワイヤ走行系が形成されるのであれば、その具体的な構成については特に限定しないものとする。 Embodiment 1 FIG.
The configuration and operation of the embodiment of the present invention will be described below.
FIG. 1 is a perspective view showing a wire electric discharge machining apparatus according to Embodiment 1 of the present invention. In the wire electrical discharge machining apparatus according to the first embodiment, one electrode wire 2 fed out from the wire bobbin 1 is sequentially spaced between the plurality of guide rollers 3a to 3f a plurality of times at a minute interval. A plurality of wire travel systems are formed by winding. The distance between the wire travel systems formed by winding the electrode wires 2 corresponds to the processing width of the workpiece 8. In other words, the workpiece 8 is applied while applying a voltage between each wire traveling system and the workpiece 8 in a state where the workpiece is disposed facing the wire traveling system by a predetermined distance. Is cut and sent to each wire traveling system, and the workpiece 8 is discharged and cut by each wire traveling system. Thereby, the columnar workpiece 8 is sliced into a thin plate. In the example of FIG. 1, an example in which one electrode wire 2 is wound around a plurality of guide rollers is shown. However, the present invention is not limited to this, and a plurality of wire runs can be performed by folding back one electrode wire 2. If a system is formed, the specific configuration is not particularly limited.

本実施の形態１においては、複数のガイドローラー３ａ〜３ｆは、互いに軸線方向に平行に離間して配置されている。最も高い位置にガイドローラー３ａと３ｂとが設けられ、ガイドローラー３ｂの下方の最も低い位置にガイドローラー３ｃが設けられ、ガイドローラー３ａの下方には、ガイドローラー３ｃと並んで、ガイドローラー３ｄが設けられている。また、ガイドローラー３ｄの斜め上方で、かつ、ガイドローラー３ａと３ｄとの高さ方向の間の位置に、ガイドローラー３ｅが設けられ、ガイドローラー３ｅの隣には、ガイドローラー３ｆ，３ｇが順にワイヤボビン１の設置方向に向けて順に並んで配置されている。 In the first embodiment, the plurality of guide rollers 3a to 3f are arranged apart from each other in parallel in the axial direction. Guide rollers 3a and 3b are provided at the highest position, a guide roller 3c is provided at the lowest position below the guide roller 3b, and the guide roller 3d is arranged below the guide roller 3a along with the guide roller 3c. Is provided. Further, a guide roller 3e is provided obliquely above the guide roller 3d and at a position between the height directions of the guide rollers 3a and 3d, and the guide rollers 3f and 3g are sequentially arranged next to the guide roller 3e. The wire bobbins 1 are arranged side by side in the direction of the installation direction.

このとき、電極ワイヤ２は、ガイドローラー３ａ〜３ｇに巻回しする毎に後述する高周波絶縁器４（図２参照）を通過する。高周波絶縁器４は、どの位置に設置してもよいが、望ましくは、ガイドローラー３ｇとワイヤボビン１との間辺りに設置して、電極ワイヤ２がガイドローラー３ａ〜３ｆに順次１回ずつ巻き回されるたびに、電極ワイヤ２のガイドローラー３ｇと３ａ間部分を高周波絶縁器４に１回通過させて、各切断ワイヤ部２ａ間の絶縁を行うようにする。 At this time, the electrode wire 2 passes the high frequency insulator 4 (refer FIG. 2) mentioned later whenever it winds around the guide rollers 3a-3g. The high frequency insulator 4 may be installed at any position, but is preferably installed between the guide roller 3g and the wire bobbin 1, and the electrode wire 2 is wound around the guide rollers 3a to 3f one by one sequentially. Each time the portion between the guide rollers 3g and 3a of the electrode wire 2 is passed through the high-frequency insulator 4 once, insulation between the cutting wire portions 2a is performed.

電極ワイヤ２は所定回数の巻回し後に、ワイヤ排出ローラー５より排出される。電極ワイヤ２は、ガイドローラー３ａと３ｂとの間の部分が、被加工物８を加工するための切断ワイヤ部分２ａとなっており、図１に示すように、当該切断ワイヤ部分２ａに対して微小間隔を隔てて被加工物８を対向させて配置し、放電加工処理を行う。また、電極ワイヤ２のガイドローラー３ｂと３ｂｃとの間の部分が、放電加工を行うための電圧（加工用電圧）が供給される給電ワイヤ部分２ｂとなっている。電極ワイヤ２の給電ワイヤ部分２ｂには、加工電源６から、給電子７を介して、放電加工を行うための電圧（加工用電圧）が給電され、被加工物８との間に電圧が印加される。加工電源６は互いに独立に電圧を印加できる複数のユニット６１からなり、給電子７もそれぞれが互いに絶縁された複数の給電子ユニット７１から構成されていて、各切断ワイヤ部分２ａに独立して電圧を印加できる構成となっている。また、加工電源６は、高周波絶縁器４により各切断ワイヤ部分２ａ相互間で十分絶縁可能なほど高い周波数、例えば１０ｋＨｚ以上、のパルス電圧を印加する。 The electrode wire 2 is discharged from the wire discharge roller 5 after being wound a predetermined number of times. In the electrode wire 2, a portion between the guide rollers 3 a and 3 b is a cutting wire portion 2 a for processing the workpiece 8, and as shown in FIG. 1, the cutting wire portion 2 a The work piece 8 is arranged to face each other with a minute interval, and an electric discharge machining process is performed. Further, a portion between the guide rollers 3b and 3bc of the electrode wire 2 serves as a power supply wire portion 2b to which a voltage for electric discharge machining (processing voltage) is supplied. The power supply wire portion 2 b of the electrode wire 2 is supplied with a voltage (processing voltage) for performing electrical discharge machining from the machining power supply 6 via the power supply 7, and the voltage is applied between the workpiece 8 and the workpiece 8. Is done. The processing power source 6 is composed of a plurality of units 61 that can apply voltages independently of each other, and the power supply 7 is also composed of a plurality of power supply units 71 that are insulated from each other. Can be applied. Further, the machining power source 6 applies a pulse voltage having a high frequency, for example, 10 kHz or more, that can be sufficiently insulated between the cutting wire portions 2 a by the high-frequency insulator 4.

なお、当然ながら、各々の切断ワイヤ部分２ａには、加工電源６から高周波電圧を印加する必要があるから、給電子７は、高周波絶縁器４と各切断ワイヤ部分２ａとの間に設置される。さらに、また当然ながら、電圧印加極性は従来のワイヤ放電加工と同様に、必要に応じて適宜反転可能となっている。被加工物８は、図示しない位置制御装置により、ガイドローラー３ａ〜３ｇ間に巻回された電極ワイヤ２と微小間隙を隔てるように位置が制御されているので、適正な放電ギャップ長が維持されている。なお、加工液は図示していないが、通常のワイヤ放電加工と同様に、吹きかけもしくは浸漬により被加工物８と電極ワイヤ２との間に供給されている。 Of course, since it is necessary to apply a high-frequency voltage from the machining power supply 6 to each cutting wire portion 2a, the power supply 7 is installed between the high-frequency insulator 4 and each cutting wire portion 2a. . Furthermore, as a matter of course, the voltage application polarity can be appropriately reversed as necessary, as in the conventional wire electric discharge machining. Since the position of the workpiece 8 is controlled by a position control device (not shown) so as to separate the electrode wire 2 wound between the guide rollers 3a to 3g from the minute gap, an appropriate discharge gap length is maintained. ing. Although not shown, the machining fluid is supplied between the workpiece 8 and the electrode wire 2 by spraying or dipping, as in normal wire electric discharge machining.

また、本実施の形態１に係るワイヤ放電加工装置においては、給電子９が、電極ワイヤ２において、ワイヤボビン１から繰り出され、ガイドローラー３ａに巻回される手前の部分の一箇所（すなわち、電極ワイヤ２の始端側の一箇所）に対して給電を可能とするように設置されている。さらに、給電子１０が、電極ワイヤ２において、複数のガイドローラー３ａ〜３ｇを経て、ワイヤ排出ローラー５により排出される部分の一箇所（すなわち、電極ワイヤ２の終端側の一箇所）に給電を可能とするように設置されている。また、断線検知用電圧を給電するための断線検知用電源１１が給電子９，１０に接続され、さらに、断線検知用電源１１には断線検知用電源制御装置１２が接続されている。なお、これらはワイヤ断線検出手段を構成する。断線検知用の電圧の値は、当然のことながら、加工電源６によって給電される加工用の電圧の値よりも低い値に設定されている。具体的には、図３のパルス波形において、ハイレベルのときの電圧の値が加工用の電圧の値であり、ローレベルのときの電圧の値が断線検知用の電圧の値である。上述した構成において、断線検知用電源１１により断線検知用電圧を印加している状態において、電極ワイヤ２に流れる微小電流を電流センサ（図示省略）などでモニタしておき、微小電流が検知されている間は、電極ワイヤ２は断線していないと判定する。一方、微小電流が検知されなくなった時点で、電極ワイヤ２に断線が発生したと判定する。なお、断線検知用電源制御装置１２はワイヤ放電加工装置の制御装置（図示していない）に接続される。このように、断線検知用の電圧を印加したときの電極ワイヤ２の導通状態に基づいて、電極ワイヤ２の断線の発生の有無を検知する。 Further, in the wire electric discharge machining apparatus according to the first embodiment, the power supply 9 is fed out from the wire bobbin 1 and is wound around the guide roller 3a in the electrode wire 2 at one place (that is, the electrode). It is installed so that electric power can be fed to one place on the starting end side of the wire 2. Further, the power supply 10 supplies power to one part of the electrode wire 2 that passes through the plurality of guide rollers 3a to 3g and is discharged by the wire discharge roller 5 (that is, one position on the terminal end side of the electrode wire 2). It is installed so that it is possible. Further, a disconnection detection power source 11 for supplying a disconnection detection voltage is connected to the power supply units 9 and 10, and a disconnection detection power source control device 12 is connected to the disconnection detection power source 11. These constitute wire breakage detection means. The value of the disconnection detection voltage is naturally set to a value lower than the value of the processing voltage supplied by the processing power supply 6. Specifically, in the pulse waveform of FIG. 3, the voltage value at the high level is the value of the processing voltage, and the voltage value at the low level is the value of the disconnection detection voltage. In the configuration described above, when a disconnection detection voltage is applied by the disconnection detection power supply 11, a minute current flowing through the electrode wire 2 is monitored by a current sensor (not shown) and the minute current is detected. While it is, it is determined that the electrode wire 2 is not disconnected. On the other hand, when the minute current is no longer detected, it is determined that the disconnection has occurred in the electrode wire 2. The disconnection detection power supply control device 12 is connected to a control device (not shown) of the wire electrical discharge machining apparatus. In this manner, the presence / absence of disconnection of the electrode wire 2 is detected based on the conduction state of the electrode wire 2 when a voltage for disconnection detection is applied.

図２に、高周波絶縁器４の構成を示す。高周波絶縁器４は、互いに所定間隔隔てて、空気（あるいは、非磁性材料）を介在させて、並列に設けられた、複数の高周波絶縁部４１から構成されている。各高周波絶縁部４１は、リング形状をした軟鉄やフェライト等の高透磁率の磁性体からなるコア４１ａと、そのコア４１ａの支柱４１ｃに対して回転自在に設けられ、電極ワイヤ２の走行に伴って回転するように設けられたホイール４１ｂとから構成されている。図２中の矢印は、電極ワイヤ２の走行方向と、それに伴うホイール４１ｂの回転方向をそれぞれ示している。当該構成において、ガイドローラー３ｇと３ａとの間の電極ワイヤ２が、図２に示すように、ホイール４１ｂに複数回巻回されて、コイル２１を構成する。このホイール４１ｂを用いることで、電極ワイヤ２の走行が円滑になり、高周波絶縁器４内での電極ワイヤ２の断線が防止される。高周波絶縁器４は、以上説明したような簡単な構成で、各切断ワイヤ部２ａ間の高周波的な絶縁が可能となる。但し、高周波絶縁器４は、図２の構成に限定されるものではなく、各切断ワイヤ部２ａ間の絶縁が可能なものであれば、いずれの構成のものを用いてもよい。また、高周波絶縁器４は、必ずしも設ける必要もなく、設けなくてもよいものとする。 FIG. 2 shows the configuration of the high-frequency insulator 4. The high-frequency insulator 4 includes a plurality of high-frequency insulating portions 41 provided in parallel with air (or a nonmagnetic material) interposed therebetween at a predetermined interval. Each high-frequency insulating portion 41 is provided rotatably with respect to a core 41a made of a magnetic material having a high magnetic permeability such as a ring-shaped soft iron or ferrite, and a support column 41c of the core 41a. And a wheel 41b provided so as to rotate. The arrows in FIG. 2 indicate the traveling direction of the electrode wire 2 and the accompanying rotation direction of the wheel 41b. In this configuration, the electrode wire 2 between the guide rollers 3g and 3a is wound around the wheel 41b a plurality of times as shown in FIG. By using this wheel 41b, the traveling of the electrode wire 2 becomes smooth, and disconnection of the electrode wire 2 in the high-frequency insulator 4 is prevented. The high frequency insulator 4 has a simple configuration as described above, and enables high frequency insulation between the cutting wire portions 2a. However, the high-frequency insulator 4 is not limited to the configuration shown in FIG. 2, and any configuration may be used as long as the insulation between the cutting wire portions 2a is possible. Further, the high-frequency insulator 4 is not necessarily provided and need not be provided.

次に、本発明の実施の形態１に係るワイヤ放電加工装置における電極ワイヤの断線検知動作について説明する。図３は、ガイドローラー３ａ〜３ｇに互いに微小な間隔を隔てて巻回される複数本の電極ワイヤ２の任意の一本に対して、加工電源６と断線検知用電源１１とにより加工中に印加される電圧波形の一例である。加工電源６は、予め設定された所定時間だけ電圧を印加し、その電圧印加が終了すると、次の電圧印加を開始するまでの休止時間を挿入する。この休止時間は任意に設定可能で、加工状況に応じて数μｓｅｃ〜数百ｍｓｅｃの範囲で調整される。このようにして、加工電源６により電圧が間欠的あるいは周期的に印加される。一方、断線検知用電源１１は、加工電源６が休止時間を挿入中に、加工電源６によって印加される加工用の電圧よりも低い値の一定電圧を断線検知用電圧として印加し、電極ワイヤ２に微小電流を通電させる。複数本の電極ワイヤ２には、それぞれ給電子７と加工電源６とによりパルス電圧が印加されるが、各電極ワイヤ２への電圧印加と休止時間挿入のタイミングはすべての電極ワイヤ２で同じである。したがって、すべての電極ワイヤ２が休止時間にある場合に、加工電源６とは別に設けられた断線検知用電源１１により電圧を印加するように制御すれば、加工中の加工電源６による加工用電圧に、断線検知用電源１１による断線検出用電圧が重畳されることを防ぐことができる。また、断線検知用電圧は高すぎると放電するおそれがあるため、加工への影響がないように、たとえば、数Ｖ〜２０Ｖ程度に設定し、数ｍＡ〜数百ｍＡ程度の電流が電極ワイヤ２に流れるようにすればよい。このとき、電極ワイヤ２に流れる微小電流を電流センサなどでモニタしておき、周期的に微小電流が検知されている間は、電極ワイヤ２は断線していないことがわかる。また、電極ワイヤ２に断線を生じた場合、これまで休止時間と同周期で検出されていた微小電流が検出されなくなるので、それにより、断線を即座に検出することができる。 Next, the disconnection detection operation of the electrode wire in the wire electric discharge machining apparatus according to Embodiment 1 of the present invention will be described. FIG. 3 shows that any one of a plurality of electrode wires 2 wound around the guide rollers 3a to 3g at a minute interval is being processed by a processing power source 6 and a disconnection detection power source 11. It is an example of the voltage waveform applied. The machining power supply 6 applies a voltage for a predetermined time set in advance, and when the voltage application is completed, inserts a pause time until the next voltage application is started. This pause time can be arbitrarily set, and is adjusted in the range of several μsec to several hundreds msec depending on the processing situation. In this way, a voltage is applied intermittently or periodically by the machining power supply 6. On the other hand, the disconnection detection power supply 11 applies a constant voltage having a value lower than the processing voltage applied by the processing power supply 6 as the disconnection detection voltage while the processing power supply 6 inserts a pause time. A small electric current is passed through. A pulse voltage is applied to each of the plurality of electrode wires 2 by the power supply 7 and the machining power source 6, but the timing of voltage application to each electrode wire 2 and insertion of rest time is the same for all electrode wires 2. is there. Therefore, when all the electrode wires 2 are in the downtime, if the voltage is controlled to be applied by the disconnection detection power supply 11 provided separately from the machining power supply 6, the machining voltage generated by the machining power supply 6 during machining is used. In addition, it is possible to prevent the disconnection detection voltage by the disconnection detection power source 11 from being superimposed. In addition, since the disconnection detection voltage may be discharged if it is too high, for example, it is set to several V to 20 V so that there is no influence on processing, and a current of several mA to several hundred mA is applied to the electrode wire 2. It should just flow. At this time, a minute current flowing through the electrode wire 2 is monitored by a current sensor or the like, and it can be seen that the electrode wire 2 is not disconnected while the minute current is periodically detected. In addition, when the electrode wire 2 is disconnected, the minute current that has been detected in the same period as the resting time is not detected so that the disconnection can be immediately detected.

このような構成によれば、休止時間挿入の周波数の速さで、非常に高速に電極ワイヤ２の断線状態を検出することができる。電極ワイヤ２の断線が検出されると、その時点で、ワイヤ放電加工装置の制御装置に、加工電源６とガイドローラー３ａ〜３ｇなどの駆動系を停止させるための指令信号を断線検知用電源制御装置１２から送ることにより、ワイヤ放電加工装置を即座に停止させることができる。このように、電極ワイヤ２の断線を検知した後、即座に、ワイヤ放電加工装置を停止することができるので、断線した電極ワイヤ２がガイドローラー３ａ〜３ｇからはずれて周囲に絡まる状況を最小限に抑えることができる。なお、本実施の形態１においては、断線検知用電源制御手段１２は、断線検知用電源１１による印加のタイミングを制御する断線検知用電源制御手段を構成するとともに、電流センサとともに、断線検知用電源１１により断線検知用の電圧を印加したときの電極ワイヤ２の導通状態に基づいて、電極ワイヤ２の断線の有無を検知する断線検出手段とを構成している。また、その場合に限らず、ワイヤ放電加工装置の制御装置と電流センサとにより断線検出手段を構成するようにしてもよい。 According to such a configuration, the disconnection state of the electrode wire 2 can be detected at a very high speed with the frequency of the pause time insertion frequency. When the disconnection of the electrode wire 2 is detected, at that time, the control device of the wire electric discharge machining apparatus sends a command signal for stopping the machining power supply 6 and the drive system such as the guide rollers 3a to 3g to the power supply control for disconnection detection. By sending from the apparatus 12, the wire electric discharge machining apparatus can be stopped immediately. Thus, since the wire electric discharge machining apparatus can be stopped immediately after detecting the disconnection of the electrode wire 2, the situation in which the disconnected electrode wire 2 is disconnected from the guide rollers 3a to 3g and becomes entangled around is minimized. Can be suppressed. In the first embodiment, the disconnection detection power source control means 12 constitutes a disconnection detection power source control means for controlling the application timing of the disconnection detection power source 11, and together with the current sensor, a disconnection detection power source. 11 is configured to detect disconnection of the electrode wire 2 based on the conduction state of the electrode wire 2 when a voltage for detecting disconnection is applied. Further, the present invention is not limited thereto, and the disconnection detecting means may be configured by a control device of the wire electric discharge machining apparatus and a current sensor.

以上のように、本実施の形態１の構成によれば、１本の電極ワイヤ２を複数のガイドローラー３ａ〜３ｇ間に巻回させて、複数の切断ワイヤ部分２ａを形成し、それぞれの切断ワイヤ部分２ａに個別に給電する加工電源６と給電子７とを備え、さらに、加工電源６と給電子７とは別に、ガイドローラー３ａ〜３ｇにおける電極ワイヤ２の巻始め部分と巻終わり部分に給電子９，１０をそれぞれ設置し、その給電子９，１０に、断線検知用電圧を給電するようにした。これにより、電極ワイヤ２の断線を迅速に検出することができ、電極ワイヤ２の断線を検知した後、即座に、ワイヤ放電加工装置を停止することができるので、断線した電極ワイヤ２がガイドローラー３ａ〜３ｇからはずれて、周辺のガイドローラーに巻き込まれたり、あるいは、周辺の電極ワイヤ２等に絡まったりする状況を最小限に抑えることができ、復旧作業の効率向上を図ることができる。また、このとき、加工電源６が印加されるタイミングと同じにならないように、加工用電圧の休止時間に合わせて断線検知用電源１１の印加電圧のタイミングを調整することで、加工用電圧に断線検知用電圧が重畳されることを防止でき、放電や加工への影響等が発生しないようにすることができ、安定した断線検出を行うことが可能である。 As described above, according to the configuration of the first embodiment, one electrode wire 2 is wound between a plurality of guide rollers 3a to 3g to form a plurality of cutting wire portions 2a, and each cutting is performed. A processing power source 6 and a power supply 7 for individually supplying power to the wire portion 2a are provided. Further, separately from the processing power source 6 and the power supply 7, the winding start portion and the winding end portion of the electrode wire 2 in the guide rollers 3a to 3g are provided. The power supplies 9 and 10 are installed, respectively, and the disconnection detection voltage is supplied to the power supplies 9 and 10. Thereby, the disconnection of the electrode wire 2 can be detected quickly, and the wire electric discharge machining apparatus can be stopped immediately after the disconnection of the electrode wire 2 is detected. It is possible to minimize the situation in which they are separated from 3a to 3g and are caught in the peripheral guide rollers, or entangled with the peripheral electrode wires 2 and the like, and the efficiency of the restoration work can be improved. At this time, the processing voltage is disconnected by adjusting the timing of the applied voltage of the disconnection detection power supply 11 in accordance with the rest time of the processing voltage so that the processing power supply 6 is not applied at the same time. It is possible to prevent the detection voltage from being superimposed, to prevent the occurrence of an influence on electric discharge and machining, and to perform stable disconnection detection.

実施の形態２．
上述の実施の形態１においては、ワイヤボビン１から繰り出され、ガイドローラー３ａ〜３ｇに巻回される手前の電極ワイヤ２の部分に給電子９を設け、かつ、複数のガイドローラー３ａ〜３ｇを経て、ワイヤ排出ローラー５により排出される電極ワイヤ２の部分に給電子１０を設けて、それらの給電子９，１０を介して電極ワイヤ２の両端に給電を行うことで、電極ワイヤ２の断線を検知する方式について説明した。すなわち、この実施の形態１による方式は、１本の電極ワイヤ２が複数のガイドローラー３ａ〜３ｇ間に巻回させて形成される複数の切断ワイヤ部分２ａのどこかで断線が発生したことを検知する方式であり、電極ワイヤ２が断線すれば直ちにワイヤ放電加工装置を停止することにより、電極ワイヤ２のほぐれによる被害の拡大を最小限に防止できるという効果がある。本実施の形態２においては、単に電極ワイヤ２の断線を検知するだけでなく、さらに、どの電極ワイヤ２が断線しているかを検知して、断線した電極ワイヤ２を復旧する場合の作業効率をより向上させるための実施の形態について説明する。 Embodiment 2. FIG.
In the above-described first embodiment, the feeder 9 is provided on the portion of the electrode wire 2 that is drawn out from the wire bobbin 1 and wound around the guide rollers 3a to 3g, and passes through the plurality of guide rollers 3a to 3g. The supply wire 10 is provided in the portion of the electrode wire 2 discharged by the wire discharge roller 5, and power is supplied to both ends of the electrode wire 2 through the supply wires 9 and 10, thereby breaking the electrode wire 2. The detection method was explained. That is, in the method according to the first embodiment, a disconnection occurs in some of the plurality of cutting wire portions 2a formed by winding one electrode wire 2 between the plurality of guide rollers 3a to 3g. This is a detection method, and if the electrode wire 2 is disconnected, the wire electric discharge machining apparatus is stopped immediately, and the effect of preventing the damage caused by the loosening of the electrode wire 2 can be minimized. In the second embodiment, not only the disconnection of the electrode wire 2 is detected, but also the work efficiency in detecting which electrode wire 2 is disconnected and restoring the disconnected electrode wire 2 is improved. An embodiment for further improvement will be described.

図４は、本発明の実施の形態２に係るワイヤ放電加工装置を示す斜視図である。図４に示すように、基本的な構成は、図１に示した実施の形態１と同じである。従って、以下の説明においては、図１の実施の形態１と異なる構成について主に説明し、同一の構成については、ここでは説明を省略する。 FIG. 4 is a perspective view showing a wire electric discharge machining apparatus according to Embodiment 2 of the present invention. As shown in FIG. 4, the basic configuration is the same as that of the first embodiment shown in FIG. Therefore, in the following description, a configuration different from the first embodiment of FIG. 1 will be mainly described, and the description of the same configuration will be omitted here.

図４に示すように、本実施の形態２においては、断線検知用電源１１の陽極側を、電極ワイヤ２において、ワイヤボビン１から繰り出され、ガイドローラー３ａ〜３ｇに巻回される手前の部分（始端側）の一箇所に、給電子９を介して接続する。また、断線検知用電源１１の陰極側を、電極ワイヤ２において、複数のガイドローラー３ａ〜３ｇ間に巻回させて形成される複数のワイヤ走行系のそれぞれの一箇所に給電子１３を介して接続する。給電子１３は、電極ワイヤ２の切断ワイヤ部分２ａ（および給電ワイヤ部分２ｂ）の個数と同数だけ設けられている。図４の例では、各給電子１３は、給電子７とガイドローラー３ｃとの間の位置に配置されているが、これに限定されるものではない。なお、このとき、断線検知用電源１１の陽極側を、電極ワイヤ２において、複数のガイドローラー３ａ〜３ｇを経て、ワイヤ排出ローラー５より排出される部分（終端側）の一箇所に接続するようにしてもよい。 As shown in FIG. 4, in the second embodiment, the anode side of the disconnection detection power supply 11 is fed out from the wire bobbin 1 and wound on the guide rollers 3 a to 3 g in the electrode wire 2 ( It is connected to one place (starting end side) via a power supply 9. In addition, the cathode side of the disconnection detection power source 11 is wound around the electrode wire 2 between the plurality of guide rollers 3a to 3g, and is fed to each one of the plurality of wire travel systems via the power supply 13. Connecting. The number of the supply electrons 13 is the same as the number of the cutting wire portions 2a (and the feeding wire portions 2b) of the electrode wire 2. In the example of FIG. 4, each of the power supplies 13 is disposed at a position between the power supply 7 and the guide roller 3 c, but is not limited to this. At this time, the anode side of the disconnection detection power supply 11 is connected to one portion of the electrode wire 2 through the plurality of guide rollers 3a to 3g and the portion discharged from the wire discharge roller 5 (terminal side). It may be.

断線検知用電源１１の陰極側とその陰極側に接続される電極ワイヤ２の各ワイヤ走行系との間には、たとえば、ＦＥＴ（Field Effect Transistor：電界効果トランジスタ）などによる断線検知用スイッチ１４（以下、単に、スイッチ１４とする。）が備えられる。スイッチ１４は、電極ワイヤ２のワイヤ走行系の個数（すなわち、切断ワイヤ部分２ａおよび給電ワイヤ部分２ｂの個数）と同数だけ設けられている。図４の例では、複数のスイッチ１４は互いに並列に接続されており、それらの複数のスイッチ１４の結線部分に断線検知用電源１１の陰極側が直列に接続されている。また、各スイッチ１４と各給電子１３とは１対１に直列に接続されている。各スイッチ１４には断線検知用電源制御装置１２から制御信号が入力され、それによって各スイッチ１４の開閉動作が行われる。当該構成において、あるスイッチ１４の一つを閉じて形成される回路に対して断線検知用電源１１による電圧を印加して、導通が検出されれば、そこまでの電極ワイヤ２では断線が無いことを意味する。次に、直前まで閉じていたスイッチ１４を開き、そのスイッチ１４のすぐ隣のスイッチ１４を閉じて断線検知用電源１１による電圧を印加して導通を調べる。導通が検出されれば、そこまでの電極ワイヤ２では断線が無いことを意味する。もし、導通が検出されない場合には、直前に導通を調べた電極ワイヤ２との差分により、いま導通を調べた電極ワイヤ２において断線が生じた可能性が高いと判断でき、断線した電極ワイヤ２の断線箇所を特定することができる。 Between the cathode side of the disconnection detection power supply 11 and each wire travel system of the electrode wire 2 connected to the cathode side, for example, a disconnection detection switch 14 (FET (Field Effect Transistor)) or the like Hereinafter, the switch 14 is simply provided. The switches 14 are provided in the same number as the number of wire traveling systems of the electrode wires 2 (that is, the number of cutting wire portions 2a and feeding wire portions 2b). In the example of FIG. 4, the plurality of switches 14 are connected in parallel to each other, and the cathode side of the disconnection detection power supply 11 is connected in series to the connection portion of the plurality of switches 14. Each switch 14 and each power supply 13 are connected in series in a one-to-one relationship. A control signal is input to each switch 14 from the disconnection detection power supply control device 12, thereby opening and closing each switch 14. In this configuration, if a voltage from the disconnection detection power supply 11 is applied to a circuit formed by closing one of the switches 14 and conduction is detected, there is no disconnection in the electrode wire 2 up to that point. Means. Next, the switch 14 that has been closed just before is opened, the switch 14 immediately adjacent to the switch 14 is closed, and a voltage is applied by the disconnection detection power supply 11 to check the continuity. If continuity is detected, it means that there is no disconnection in the electrode wire 2 so far. If continuity is not detected, it can be determined that there is a high possibility that a disconnection has occurred in the electrode wire 2 that has been checked for continuity based on the difference from the electrode wire 2 that has been checked for continuity immediately before. Can be identified.

本実施の形態２に係るワイヤ放電加工装置のスイッチ１４を上述のようにＦＥＴで構成すれば、電気信号によるスイッチ開閉制御が可能であり、そのスイッチ開閉動作は非常に高速である。また、ソフトウエア等による自動制御が可能であるため、人手を介さずに、順次、スイッチの開閉動作を行うことができる。このようにすることにより、スイッチ開閉動作を電極ワイヤ一本ずつに対して順次行うことで、各電極ワイヤ２の導通を調べる。任意の電極ワイヤ２の導通を調べるとともに、その直前のワイヤの導通調査結果との差分により、複数の電極ワイヤ２それぞれに対する断線検出が可能となり、断線が生じた電極ワイヤ２を容易にかつ精度良く特定でき、復旧作業の効率向上を図ることができる。 If the switch 14 of the wire electrical discharge machining apparatus according to the second embodiment is formed of an FET as described above, switch opening / closing control by an electric signal is possible, and the switch opening / closing operation is very fast. In addition, since automatic control by software or the like is possible, it is possible to sequentially open and close the switches without human intervention. In this way, the continuity of each electrode wire 2 is checked by sequentially performing the switch opening / closing operation for each electrode wire. In addition to checking the continuity of an arbitrary electrode wire 2, it is possible to detect the disconnection of each of the plurality of electrode wires 2 based on the difference from the continuity investigation result of the immediately preceding wire, and the electrode wire 2 in which the disconnection has occurred can be easily and accurately detected. It can be identified and the efficiency of recovery work can be improved.

以上のように、本実施の形態２によれば、上述の実施の形態１と同様の効果が得られるとともに、さらに、断線検知用電源１１の一端を、複数のガイドローラー３ａ〜３ｇ間に巻回させて形成される複数の電極ワイヤ２のそれぞれに、スイッチ１４を介して接続し、スイッチ１４の開閉動作により、各電極ワイヤ２の断線の有無を確認するようにしたので、断線が生じた電極ワイヤ２を容易にかつ精度良く特定でき、復旧作業の効率向上を図ることができる。 As described above, according to the second embodiment, the same effects as those of the first embodiment described above can be obtained, and one end of the disconnection detection power supply 11 is wound between the plurality of guide rollers 3a to 3g. Since each of the plurality of electrode wires 2 formed by rotating is connected via the switch 14 and the opening / closing operation of the switch 14 confirms whether or not each electrode wire 2 is disconnected, a disconnection has occurred. The electrode wire 2 can be identified easily and accurately, and the efficiency of the restoration work can be improved.

なお、上述の説明においては、断線検知用電源１１の陰極側を電極ワイヤ２のワイヤ走行系の一箇所に接続し、陽極側を電極ワイヤ２の始端側または終端側の一箇所に接続する例について説明したが、その場合に限らず、陰極側と陽極側とは逆にしてもよい。 In the above description, the cathode side of the disconnection detection power source 11 is connected to one place of the wire traveling system of the electrode wire 2, and the anode side is connected to one place of the starting end side or the terminating end side of the electrode wire 2. However, the present invention is not limited to this, and the cathode side and the anode side may be reversed.

実施の形態３．
図５は、本発明の実施の形態３に係るワイヤ放電加工装置を示す斜視図である。本実施の形態３の構成は、基本的に図１に示した実施の形態１と同じであり、図１の実施の形態１とは、断線検出に関する部分のみが異なるため、本実施の形態においては、断線検出に関する部分について説明し、他の構成については説明を省略する。 Embodiment 3 FIG.
FIG. 5 is a perspective view showing a wire electric discharge machining apparatus according to Embodiment 3 of the present invention. The configuration of the third embodiment is basically the same as that of the first embodiment shown in FIG. 1 and differs from the first embodiment of FIG. 1 only in the part relating to disconnection detection. Will describe the portion related to disconnection detection, and the description of the other components will be omitted.

本実施の形態３においても、上述の実施の形態１および２と同様に、ワイヤボビン１から繰り出された電極ワイヤ２が、複数のガイドローラー３ａ〜３ｇ間を複数回、互いに微小な間隔を隔てて巻回されて複数のワイヤ走行系が形成され、最終的に電極ワイヤ２は所定回数の巻回し後に、ワイヤ排出ローラー５より排出される。このとき、本実施の形態３においては、ワイヤ押さえ板１５が、たとえば、ガイドローラー３ｂおよび３ｃ間に設けられている。ワイヤ押さえ板１５は、電極ワイヤ２の各ワイヤ走行系がそのワイヤ押さえ板１５の片側の面（以下、ワイヤ押さえ面とする。）に押し付けられるように設置される。このワイヤ押さえ板１５には、ワイヤ押さえ面とは反対側の面（以下、ＡＥセンサ設置面とする。）にＡＥ（アコースティックエミッション）センサ１６が取り付けられている。ＡＥセンサ１６はアンプ１７に接続され、アンプ１７はＡ／Ｄ変換器１８に接続され、Ａ／Ｄ変換器１８はワイヤ放電加工装置の制御装置（図示せず）に接続されている。 Also in the third embodiment, as in the first and second embodiments described above, the electrode wire 2 fed out from the wire bobbin 1 is spaced a plurality of times from each other between the plurality of guide rollers 3a to 3g. A plurality of wire running systems are formed by winding, and finally the electrode wire 2 is discharged from the wire discharge roller 5 after being wound a predetermined number of times. At this time, in the third embodiment, the wire pressing plate 15 is provided between the guide rollers 3b and 3c, for example. The wire pressing plate 15 is installed so that each wire traveling system of the electrode wire 2 is pressed against one surface of the wire pressing plate 15 (hereinafter referred to as a wire pressing surface). An AE (acoustic emission) sensor 16 is attached to the wire pressing plate 15 on a surface opposite to the wire pressing surface (hereinafter referred to as an AE sensor installation surface). The AE sensor 16 is connected to an amplifier 17, the amplifier 17 is connected to an A / D converter 18, and the A / D converter 18 is connected to a control device (not shown) of a wire electric discharge machining apparatus.

次に、実施の形態３の動作について説明する。ワイヤ押さえ板１５は、微小な間隔を隔てて並走する複数の電極ワイヤ２すべてがワイヤ押さえ板１５のワイヤ押さえ面に接触するように設置されているので、電極ワイヤ２の断線によって発生する超音波を含む弾性波（ＡＥ）がこのワイヤ押さえ板１５に伝播する。この弾性波をワイヤ押さえ面の反対側のＡＥセンサ設置面に取り付けられたＡＥセンサ１６によって検出しＡＥ信号として出力する。ＡＥセンサ１６によって得られたＡＥ信号はアンプ１７にて増幅され、Ａ／Ｄ変換器１８によってＡ／Ｄ変換された後、ワイヤ放電加工装置の制御装置（図示せず）に入力される。本実施の形態３においては、ＡＥセンサ１６（あるいは、ＡＥセンサ１６、アンプ１７、および、Ａ／Ｄ変換器１８）が、ワイヤ押さえ板１５に伝播されてくる弾性波（ＡＥ）を検出して検出信号としてＡＥ信号を出力する弾性波検出手段を構成している。ワイヤ放電加工装置の制御装置が、弾性波検出手段から出力されるＡＥ信号が所定の基準値を超えたときに、電極ワイヤ２に断線が発生したとして検知する断線検出手段を構成している。 Next, the operation of the third embodiment will be described. Since the wire pressing plate 15 is installed so that all of the plurality of electrode wires 2 that run in parallel at a minute interval are in contact with the wire pressing surface of the wire pressing plate 15, the wire pressing plate 15 is super Elastic waves (AE) including sound waves propagate to the wire pressing plate 15. This elastic wave is detected by the AE sensor 16 attached to the AE sensor installation surface on the opposite side of the wire pressing surface and output as an AE signal. The AE signal obtained by the AE sensor 16 is amplified by the amplifier 17, A / D converted by the A / D converter 18, and then input to a control device (not shown) of the wire electric discharge machining apparatus. In the third embodiment, the AE sensor 16 (or the AE sensor 16, the amplifier 17, and the A / D converter 18) detects the elastic wave (AE) transmitted to the wire pressing plate 15. An elastic wave detecting means for outputting an AE signal as a detection signal is configured. The control device of the wire electric discharge machining apparatus constitutes a breakage detection means for detecting that a breakage has occurred in the electrode wire 2 when the AE signal output from the elastic wave detection means exceeds a predetermined reference value.

図６は、上述のようにして得られるワイヤ断線時のＡＥ信号の例である。ＡＥ信号のレベルが、予め設定されている所定のワイヤ断線判別基準値を超えると、Ａ／Ｄ変換器１８により、たとえば、図６のように、ワイヤ断線時のＡＥ信号に対してはハイレベルとするデジタル信号に変換されて、ワイヤ放電加工装置の制御装置に入力される。制御装置がそのデジタル信号のハイレベルを検知すると、制御装置は、ワイヤ放電加工装置を停止させるための制御信号を直ちに出力して、停止させるので、ワイヤ断線に伴う被害を最小限に抑えることができる。 FIG. 6 is an example of the AE signal at the time of wire breakage obtained as described above. When the level of the AE signal exceeds a predetermined wire breakage discrimination reference value set in advance, the A / D converter 18 causes the AE signal at the time of wire breakage to be at a high level as shown in FIG. And is input to the control device of the wire electric discharge machining apparatus. When the control device detects the high level of the digital signal, the control device immediately outputs and stops the control signal for stopping the wire electric discharge machining device, so that damage caused by the wire breakage can be minimized. it can.

なお、ワイヤ押さえ板１５に設置されるＡＥセンサ１６は１個でもワイヤ断線を検出することが可能であるが、複数個のＡＥセンサを取り付けることでワイヤ断線の検出感度をさらに向上させることができる。図７に、ワイヤ押さえ板１５のワイヤ押さえ面とは反対側のＡＥセンサ設置面に複数のＡＥセンサ２６を直線状に設置した本発明のワイヤ放電加工装置の構成を示す。各ＡＥセンサ２６にはそれぞれアンプ２７が接続され、それらのアンプ２７にはＡ／Ｄ変換器２８が接続され、それらのＡ／Ｄ変換器２８はワイヤ放電加工装置の制御装置（図示せず）に接続される。 Note that even one AE sensor 16 installed on the wire holding plate 15 can detect wire breakage, but the sensitivity of wire breakage detection can be further improved by attaching a plurality of AE sensors. . FIG. 7 shows a configuration of the wire electric discharge machining apparatus of the present invention in which a plurality of AE sensors 26 are linearly installed on the AE sensor installation surface opposite to the wire pressing surface of the wire pressing plate 15. An amplifier 27 is connected to each AE sensor 26, and an A / D converter 28 is connected to each of the amplifiers 27. The A / D converter 28 is a control device (not shown) of a wire electric discharge machining apparatus. Connected to.

次に、図７の構成において、ワイヤ断線が発生した場合の動作について説明する。複数設置されているＡＥセンサ２６の各出力信号は、図６に示したＡＥセンサ１６の出力信号と基本的に同じである。但し、複数設置されているＡＥセンサ２６のうち、断線した電極ワイヤ２にもっとも近い位置に設置されているＡＥセンサ２６がもっとも大きな出力値を示す。したがって、ＡＥセンサ２６が１個の場合では、そのＡＥセンサ２６が断線した電極ワイヤ２から遠い場合には、断線検出信号の出力は小さくなる。しかし、ＡＥセンサ２６が複数設置していることで、前述のように断線した電極ワイヤ２６とＡＥセンサ２６との位置関係に起因して電極ワイヤ２の断線の検出信号の出力値が著しく小さくなることはなく、ワイヤ断線検出を安定して行うことができる。 Next, the operation when a wire breakage occurs in the configuration of FIG. 7 will be described. Each output signal of the plurality of AE sensors 26 installed is basically the same as the output signal of the AE sensor 16 shown in FIG. However, among the plurality of AE sensors 26 installed, the AE sensor 26 installed at the position closest to the disconnected electrode wire 2 shows the largest output value. Therefore, in the case where there is one AE sensor 26, when the AE sensor 26 is far from the disconnected electrode wire 2, the output of the disconnection detection signal is small. However, since a plurality of AE sensors 26 are installed, the output value of the detection signal of the disconnection of the electrode wire 2 due to the positional relationship between the electrode wire 26 and the AE sensor 26 that have been disconnected as described above becomes extremely small. There is no problem, and wire breakage detection can be performed stably.

以上のように、本実施の形態３によれば、側面のうちの１つを電極ワイヤ２に接触させてワイヤ押さえ板１５を設けて、当該側面とは反対側の側面に、ＡＥセンサ１６または２６を設けて、電極ワイヤ２６の断線により発生するＡＥ信号を即座に検出し、ワイヤ放電加工装置を迅速に停止させるようにしたので、電極ワイヤ２が切断したまま気づかずに装置を作動させることを防止でき、電極ワイヤ２がガイドローラー３ａ〜３ｇからはずれ、周囲に絡まる状況を最小限に抑えることができ、復旧作業の効率向上を図ることができる。 As described above, according to the third embodiment, one of the side surfaces is brought into contact with the electrode wire 2 to provide the wire pressing plate 15, and the AE sensor 16 or the side surface opposite to the side surface is provided. 26, the AE signal generated by the disconnection of the electrode wire 26 is immediately detected, and the wire electric discharge machining apparatus is quickly stopped, so that the apparatus can be operated without being noticed while the electrode wire 2 is cut. The situation in which the electrode wire 2 is separated from the guide rollers 3a to 3g and entangled with the surroundings can be minimized, and the efficiency of the restoration work can be improved.

なお、上記の実施の形態１〜３においては、複数のガイドローラーに電極ワイヤ２を巻回して、互いに離間して設けられた複数のワイヤ走行系を有するワイヤ放電加工装置を例に挙げて説明したが、その場合に限らず、被加工物との間で放電を発生させる１以上の電極ワイヤを備えたワイヤ放電加工装置であれば、巻き回していないタイプのものでもよく、また、その他のいずれのものにも、本発明の実施の形態１〜３に記載の発明を適用することができることは言うまでない。 In the first to third embodiments described above, a wire electric discharge machining apparatus having a plurality of wire traveling systems that are provided apart from each other by winding the electrode wire 2 around a plurality of guide rollers will be described as an example. However, the present invention is not limited to this, and any wire electric discharge machining apparatus provided with one or more electrode wires that generate electric discharge with the workpiece may be of an unwinding type or other It goes without saying that the invention described in Embodiments 1 to 3 of the present invention can be applied to any of them.

本発明の実施の形態１によるワイヤ放電加工装置の構成を示す斜視図である。It is a perspective view which shows the structure of the wire electric discharge machining apparatus by Embodiment 1 of this invention. 本発明の実施の形態１によるワイヤ放電加工装置に設けられた高周波絶縁器の構成を示した構成図である。It is the block diagram which showed the structure of the high frequency insulator provided in the wire electric discharge machining apparatus by Embodiment 1 of this invention. 本発明の実施の形態１によるワイヤ断線検出用電圧の印加部分を示す説明図である。It is explanatory drawing which shows the application part of the voltage for wire disconnection detection by Embodiment 1 of this invention. 本発明の実施の形態２によるワイヤ放電加工装置の構成を示す斜視図である。It is a perspective view which shows the structure of the wire electric discharge machining apparatus by Embodiment 2 of this invention. 本発明の実施の形態３によるワイヤ放電加工装置の構成を示す斜視図である。It is a perspective view which shows the structure of the wire electric discharge machining apparatus by Embodiment 3 of this invention. 本発明の実施の形態３によるワイヤ放電加工装置におけるワイヤ断線によるＡＥセンサの信号の変動を示した説明図である。It is explanatory drawing which showed the fluctuation | variation of the signal of the AE sensor by the wire disconnection in the wire electric discharge machining apparatus by Embodiment 3 of this invention. 本発明の実施の形態３によるワイヤ放電加工装置の変形例における複数のＡＥセンサを取り付けた構成を示した斜視図である。It is the perspective view which showed the structure which attached the some AE sensor in the modification of the wire electric discharge machining apparatus by Embodiment 3 of this invention.

Explanation of symbols

１ワイヤボビン、２電極ワイヤ、２ａ切断ワイヤ部分、２ｂ給電ワイヤ部分、３ａ，３ｂ，３ｃ，３ｄ，３ｅ，３ｆ，３ｇガイドローラー、４高周波絶縁器、５ワイヤ排出ローラー、６加工電源、７給電子、８被加工物、９，１０給電子、１１断線検知用電源、１２断線検知用電源制御装置、１４断線検知用スイッチ、１５ワイヤ押さえ板、１６，２６ＡＥセンサ、１７，２７アンプ、１８，２８Ａ／Ｄ変換器、２１コイル、４１高周波絶縁部、４１ａコア、４１ｂホイール、４１ｃ支柱、６１加工電源ユニット、７１給電子ユニット。 DESCRIPTION OF SYMBOLS 1 Wire bobbin, 2 Electrode wire, 2a Cutting wire part, 2b Feeding wire part, 3a, 3b, 3c, 3d, 3e, 3f, 3g Guide roller, 4 High frequency insulator, 5 Wire discharge roller, 6 Processing power supply, 7 Electric supply , 8 Workpiece, 9, 10 Power supply, 11 Disconnection detection power supply, 12 Disconnection detection power supply control device, 14 Disconnection detection switch, 15 Wire holding plate, 16, 26 AE sensor, 17, 27 Amplifier, 18, 28 A / D converter, 21 coil, 41 high frequency insulation part, 41a core, 41b wheel, 41c strut, 61 processing power supply unit, 71 power supply unit.

Claims

An electrode wire that generates an electrical discharge between the workpiece and
A machining power source for applying a pulsed machining voltage between the electrode wire and the workpiece;
A disconnection detection power source for applying a disconnection detection voltage to both ends of the electrode wire;
A disconnection detection power control means for controlling the timing of the application by the disconnection detection power;
A disconnection detecting means for detecting the presence or absence of disconnection of the electrode wire based on a conduction state of the electrode wire when the voltage for disconnection detection is applied by the power source for disconnection detection;
The disconnection detection power source control means controls the timing so that the disconnection detection voltage is applied only during a period in which the pulsed processing voltage is not applied by the processing power source. A wire electric discharge machining apparatus.

A plurality of wire travel systems formed by folding back one electrode wire and provided in parallel and spaced apart from each other;
A machining power source for applying a pulsed machining voltage between the wire running system and the workpiece in a state where the workpiece is disposed facing each of the wire running systems,
A disconnection detection power source for applying a disconnection detection voltage between one start side and one end side of the one electrode wire;
A disconnection detection power control means for controlling the timing of the application by the disconnection detection power;
A disconnection detecting means for detecting the presence or absence of disconnection of the electrode wire based on a conduction state of the electrode wire when the voltage for disconnection detection is applied by the power source for disconnection detection;
The disconnection detection power source control means controls the timing so that the disconnection detection voltage is applied only during a period in which the pulsed processing voltage is not applied by the processing power source. A wire electric discharge machining apparatus.

A plurality of wire travel systems formed by folding back one electrode wire and provided in parallel and spaced apart from each other;
A machining power source for applying a pulsed machining voltage between the wire running system and the workpiece in a state where the workpiece is disposed facing each of the wire running systems,
A disconnection detection power source that applies a voltage for disconnection detection between one place of each of the wire travel systems and one place on the start end side or one end side of the electrode wire;
A disconnection detection power control means for controlling the timing of the application by the disconnection detection power;
A disconnection detecting means for detecting the presence or absence of disconnection of the electrode wire based on a conduction state of the electrode wire when the voltage for disconnection detection is applied by the power source for disconnection detection;
The disconnection detection power supply is connected to each wire travel system via a switch, and the disconnection detection voltage is sequentially applied to each wire travel system by opening and closing the switch. Done
The disconnection detection power source control means applies the disconnection detection power source so as to apply the disconnection detection voltage only during a period in which the pulsed processing voltage is not applied by the processing power source. The wire electric discharge machining apparatus is characterized in that the timing is controlled.

A plurality of wire travel systems formed by folding back one electrode wire and provided in parallel and spaced apart from each other;
A machining power source for applying a pulsed machining voltage between the wire running system and the workpiece in a state where the workpiece is disposed facing each of the wire running systems,
A wire pressing plate provided by bringing one surface into contact with one place of each of the wire traveling systems;
An elastic wave detecting means provided on a surface opposite to the one surface of the wire pressing plate, detecting an elastic wave propagating to the wire pressing plate and outputting a detection signal;
A wire electric discharge machining apparatus, comprising: a disconnection detection unit configured to detect that a disconnection has occurred in the electrode wire when a detection signal output from the elastic wave detection unit exceeds a predetermined reference value.

The wire travel in a state where a plurality of wire travel systems formed by folding one electrode wire apart from each other and arranged in parallel, and a work piece disposed facing each of the wire travel systems A wire breakage detection method in a wire electric discharge machining apparatus comprising a machining power source for applying a pulsed machining voltage between a system and the workpiece,
A timing control step for controlling the timing of applying a voltage for detecting disconnection;
In a timing based on the control of the timing control step, a disconnection detection voltage application step of applying a disconnection detection voltage between one place on the start end side and one place on the end side of the one electrode wire,
A disconnection detecting step for detecting the presence or absence of disconnection of the electrode wire based on the conduction state of the electrode wire when the voltage for detecting disconnection is applied, and
In the timing control step, the timing is controlled so that the disconnection detection voltage is applied only during a period in which the pulsed machining voltage is not applied by the machining power source. Wire break detection method.

The wire travel in a state where a plurality of wire travel systems formed by folding one electrode wire apart from each other and arranged in parallel, and a work piece disposed facing each of the wire travel systems A wire breakage detection method in a wire electric discharge machining apparatus comprising a machining power source for applying a pulsed machining voltage between a system and the workpiece,
A timing control step for controlling the timing of applying a voltage for detecting disconnection;
At a timing based on the control in the timing control step, a disconnection detection voltage is applied between one place of each wire traveling system and one place on the starting end side or one end side of the electrode wire. Voltage application step for disconnection detection;
A disconnection detecting step for detecting the presence or absence of disconnection of the electrode wire based on the conduction state of the electrode wire when the voltage for detecting disconnection is applied, and
The disconnection detection voltage applying step applies the disconnection detection voltage via a switch provided for each wire traveling system, and the disconnection detection voltage is detected by opening and closing the switch. Is sequentially applied to each of the wire travel systems,
The wire break detection method, wherein the timing control step performs the timing control so that the break detection voltage is applied only during a period in which the machining voltage is not applied.

The wire travel in a state where a plurality of wire travel systems formed by folding one electrode wire apart from each other and arranged in parallel, and a work piece disposed facing each of the wire travel systems A wire breakage detection method in a wire electric discharge machining apparatus comprising a machining power source for applying a pulsed machining voltage between a system and the workpiece,
A pressing plate installation step for providing a wire pressing plate by bringing one surface into contact with one place of each of the wire traveling systems,
Elastic wave detection step of detecting an elastic wave propagating to the wire pressing plate on a surface opposite to the one side surface of the wire pressing plate by a sensor and outputting a detection signal;
A wire breakage detection method comprising: a breakage detection step of detecting that a breakage has occurred in the electrode wire when a detection signal obtained by the elastic wave detection step exceeds a predetermined reference value.