JPS6344495B2 - - Google Patents
Info
- Publication number
- JPS6344495B2 JPS6344495B2 JP59158609A JP15860984A JPS6344495B2 JP S6344495 B2 JPS6344495 B2 JP S6344495B2 JP 59158609 A JP59158609 A JP 59158609A JP 15860984 A JP15860984 A JP 15860984A JP S6344495 B2 JPS6344495 B2 JP S6344495B2
- Authority
- JP
- Japan
- Prior art keywords
- drilling
- chips
- abnormality
- signal
- infrared
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000005553 drilling Methods 0.000 claims description 43
- 230000005856 abnormality Effects 0.000 claims description 28
- 238000001514 detection method Methods 0.000 claims description 20
- 230000007423 decrease Effects 0.000 claims description 2
- 238000009792 diffusion process Methods 0.000 claims 1
- 229920003002 synthetic resin Polymers 0.000 description 5
- 239000000057 synthetic resin Substances 0.000 description 5
- 239000007779 soft material Substances 0.000 description 2
- WSMQKESQZFQMFW-UHFFFAOYSA-N 5-methyl-pyrazole-3-carboxylic acid Chemical compound CC1=CC(C(O)=O)=NN1 WSMQKESQZFQMFW-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 description 1
- 229910052451 lead zirconate titanate Inorganic materials 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
- B23Q17/00—Arrangements for observing, indicating or measuring on machine tools
- B23Q17/09—Arrangements for observing, indicating or measuring on machine tools for indicating or measuring cutting pressure or for determining cutting-tool condition, e.g. cutting ability, load on tool
- B23Q17/0952—Arrangements for observing, indicating or measuring on machine tools for indicating or measuring cutting pressure or for determining cutting-tool condition, e.g. cutting ability, load on tool during machining
- B23Q17/0985—Arrangements for observing, indicating or measuring on machine tools for indicating or measuring cutting pressure or for determining cutting-tool condition, e.g. cutting ability, load on tool during machining by measuring temperature
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Machine Tool Sensing Apparatuses (AREA)
- Drilling And Boring (AREA)
Description
【発明の詳細な説明】
〔発明の技術分野〕
本発明は、たとえばドリルの破損を自動的に検
出することのできる穿孔異常検出装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a drilling abnormality detection device that can automatically detect, for example, damage to a drill.
近時、加工作業の自動化にともない、工具の破
損の検出も自動化する趨勢下にある。たとえば穿
孔作業においても例えばドリルの破損などに基因
する穿孔異常の自動検出が一部において実用化し
ている。この場合の検出方法としては、ドリルの
破損に基因する異常振動を把捉するか、あるいは
穿孔により発生した切屑の通過の有無を光電素子
により検知するかの二つの方法が一般に行われて
いる。
Recently, with the automation of machining operations, there is a trend toward automating the detection of tool damage. For example, in drilling work, automatic detection of drilling abnormalities caused by breakage of the drill, for example, has been put into practical use in some areas. In this case, two methods are generally used to detect abnormal vibrations caused by damage to the drill, or to use a photoelectric element to detect the passage of chips generated during drilling.
しかしながら、上記従来のドリル破損検出方法
は、たとえば鋼、銅等の金属を被穿孔体とし、か
つ比較的大径孔穿孔用ドリルの破損検出には有効
な手法であるが、被穿孔体が例えば合成樹脂であ
つて、かつ小径孔穿孔用ドリルの破損検出には適
していない。なぜならば、小径孔の穿孔によつて
得られる合成樹脂切屑は、すこぶる小さく、かつ
半透明体であるため光電素子による検出が困難で
あるためである。また、被穿孔体が合成樹脂であ
る場合は、ドリルが破損しても異常と正常との峻
別に利用できる振動がほとんど発生しないためで
ある。 However, the conventional drill damage detection method described above is effective for detecting damage to a drill for drilling a relatively large diameter hole when the object to be drilled is a metal such as steel or copper. It is made of synthetic resin and is not suitable for detecting damage to drills for drilling small diameter holes. This is because the synthetic resin chips obtained by drilling small diameter holes are extremely small and semitransparent, making them difficult to detect with a photoelectric element. Furthermore, if the object to be drilled is made of synthetic resin, even if the drill is damaged, there will be almost no vibration that can be used to distinguish between abnormality and normality.
本発明は、上記事情を勘案してなされたもの
で、小径ドリルによる穿孔状態の良否を自動的か
つ正確に検出することのできる穿孔異常検出装置
を提供することを目的とする。
The present invention has been made in consideration of the above circumstances, and it is an object of the present invention to provide a drilling abnormality detection device that can automatically and accurately detect the quality of drilling by a small-diameter drill.
穿孔による切屑の発生部位に近接して吸入体を
配設するとともに、この吸入体に赤外線検出部を
取付けて、吸入体により吸入されている切屑より
放射される赤外線を受光して電気信号に変換し、
変換された電気信号に基づいて穿孔異常を検出す
るようにしたものである。
A suction body is placed close to the site where chips are generated due to drilling, and an infrared detection unit is attached to this suction body to receive infrared rays emitted from the chips being sucked in by the suction body and convert it into an electrical signal. death,
A drilling abnormality is detected based on the converted electrical signal.
以下、本発明の一実施例を図面を参照して詳述
する。
Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.
第１図は、この実施例の穿孔異常検出装置を示
している。この穿孔異常検出装置は、ドリル１に
よる穿孔により加工物２から生じた切屑３を吸引
する吸引部４と、この吸引部４により吸引されて
いる切屑３の接近を検出して電気信号に変換する
赤外線検出部５と、この赤外線検出部５から出力
された電気信号SAを増幅する例えばチヨツパな
どの増幅回路６と、この増幅回路６から出力され
た電気信号SBを２値化信号SCに変換する２値化
回路７と、この２値化信号SC及びボール盤の制
御部８から出力された穿孔期間信号SDを入力し
両者の論理値が「１」であるときのみ穿孔異常信
号SEを出力するゲート回路９と、このゲート回
路９からの穿孔異常信号SEを入力し警報を発す
る警報装置９ａとから構成されている。しかし
て、吸引部４は、ドリル１が握持されているチヤ
ツク１０が軸支されている軸受部１０ａに例えば
ばねなどの弾性体を介してほぼ同軸に懸吊されド
リル１が遊挿されている円筒状の吸入体１１と、
一端部がこの吸入体１１の上端部に接続された可
撓性の吸入管１２と、この吸入管の他端部が切屑
回収フイルタ１３を介して接続された真空源１４
とからなつている。上記吸入体１１の下端部は半
球状に拡径して集光部１５をなしている。この集
光部１５の内面は、鏡面仕上げされ凹面鏡となつ
ている。さらに、赤外線検出部５は、吸入体１１
の円筒部１６と集光部１５との円環状境界に沿つ
て着設されていて、タンタル酸リチウム、チタン
酸ジルコン酸鉛等のセラミツク強誘電体単結晶を
主体とするものであつて、切屑３からの赤外線を
受光すると、受光量に対応した大きさの電圧を有
する電気信号SAに変換するようになつている。
このとき切屑３からの赤外線は、集光部１５によ
り光学的に増幅されるようになつている。さら
に、２値化回路７には、閾値VTが設定され、電
気信号SBが、この閾値VT以上であれば、「切屑
発生」を意味する論理値「０」の信号SCが、逆
に閾値VT未満であれば、「切屑なし」を意味する
論理値「１」の信号SCが出力されるようになつ
ている。また、ゲート回路９は、ANDゲートと
なつている。さらに、このゲート回路９から出力
された警報信号SEは、制御部８にも出力される
ようになつていて、この制御部８にては、警報信
号SEを入力するとドリル１の送りを停止して原
位置まで上昇させるようになつている。 FIG. 1 shows the drilling abnormality detection device of this embodiment. This drilling abnormality detection device includes a suction unit 4 that sucks chips 3 generated from a workpiece 2 due to drilling with a drill 1, and detects the approach of the chips 3 being sucked by the suction unit 4 and converts it into an electrical signal. An infrared detector 5, an amplifier circuit 6 such as a chopper for amplifying the electric signal SA output from the infrared detector 5, and an amplifier circuit 6, such as a chopper, which converts the electric signal SB output from the amplifier circuit 6 into a binary signal SC. A gate that inputs the binarization circuit 7 and the binarization signal SC and the drilling period signal SD output from the control unit 8 of the drilling machine and outputs the drilling abnormality signal SE only when the logical value of both is "1". It consists of a circuit 9 and an alarm device 9a which receives the drilling abnormality signal SE from the gate circuit 9 and issues an alarm. Thus, the suction part 4 is suspended almost coaxially via an elastic body such as a spring to a bearing part 10a on which a chuck 10 holding the drill 1 is supported, and the drill 1 is loosely inserted therein. A cylindrical suction body 11,
A flexible suction pipe 12 with one end connected to the upper end of the suction body 11, and a vacuum source 14 connected with the other end of the suction pipe via a chip collection filter 13.
It is made up of. The lower end portion of the suction body 11 has a hemispherical diameter expanded to form a light condensing portion 15 . The inner surface of this condensing portion 15 is mirror-finished to form a concave mirror. Further, the infrared detecting section 5 detects the inhaler 11
It is attached along the annular boundary between the cylindrical part 16 and the condensing part 15, and is mainly made of ceramic ferroelectric single crystal such as lithium tantalate or lead zirconate titanate. When receiving infrared light from 3, it is converted into an electrical signal SA having a voltage corresponding to the amount of light received.
At this time, the infrared rays from the chips 3 are optically amplified by the condenser 15. Furthermore, a threshold value V T is set in the binarization circuit 7, and if the electric signal SB is equal to or higher than this threshold value V T , the signal SC with a logical value of “0”, which means “chip generation”, is set. If it is less than the threshold value V T , a signal SC with a logic value of "1" meaning "no chips" is output. Furthermore, the gate circuit 9 is an AND gate. Furthermore, the alarm signal SE output from the gate circuit 9 is also output to the control section 8, and when the alarm signal SE is input, the control section 8 stops feeding the drill 1. It is designed so that it can be raised to its original position.
しかして、上記構成の穿孔異常検出装置におい
て、まず、加工物２をボール盤の加工物保持台１
７に固設する。この加工物２は、合成樹脂製の多
層印刷配線基板からなつている。しかして、制御
部８からの制御信号に基づき、チヤツク１０が連
結されている主軸が回転し、ドリル１が回転駆動
され、同時に矢印１９ａ方向に下降する。このと
き、集光部１５の下端面が加工物２に当接する
が、吸入体１１は、軸受部１０ａに弾性的に懸吊
されているので、ドリル１の送りに支障をきたす
ことはない。また同時に、真空源１４を作動さ
せ、矢印２０方向に排気する。かくして、ドリル
１により加工物２の穿孔が開始すると、切屑３が
発生する。すると、発生した切屑３は、矢印２０
方向に吸入され、集光部１５、円筒部１６及び吸
入管１２を経て切屑回収フイルタ１３に回収され
る。ところで、切屑３が集光部１５に接近する際
に、切屑３から放射されている赤外線は、集光部
１５にて光学的増幅を受け、増幅された赤外線
は、赤外線検出部５にて受光され、受光量に対応
する大きさの電圧値を有する電気信号SAに、変
換される（第２図参照）。この電気信号SAは、増
幅回路６にて、増幅され、増幅された電気信号
SBが２値化信号７に出力される。この２値化回
路７においては、電気信号SBの電圧値が閾値VT
よりも大きいので、論理値「０」を示す信号SC
がゲート回路９に出力される。このゲート回路９
には、穿孔期間中、制御部８から論理値「１」の
穿孔期間信号SDが入力している。しかして、こ
れら信号SC，SDを入力したゲート回路９から
は、信号SCの論理値が「０」であるので、論理
値「１」の穿孔異常信号SEは出力されない。し
かし、穿孔中に、ドリル１が破損したり、切屑の
つまりなどにより切屑３の流出が円滑に行われな
くなると、赤外線検出部５における赤外線受光量
は、急激に減少する（第２図矢印２１部分）。そ
れゆえ、２値化回路７からは、論理値「１」の電
気信号SCがゲート回路９に出力される。ついで、
ゲート回路９にては、いずれも論理値「１」の信
号SC，SDの論理積がとられ、論理値「１」の穿
孔異常信号SEが警報装置９ａ及び制御部８に出
力される。かくして、警報装置９ａからは、穿孔
異常を告げる警報音が発せられると同時に、制御
部８からは、ドリル１を矢印１９ｂ方向に上昇さ
せ、その回転を停止させる制御信号が出力され
る。 Therefore, in the drilling abnormality detection device configured as described above, first, the workpiece 2 is placed on the workpiece holding table of the drilling machine.
Fixedly installed at 7. This workpiece 2 consists of a multilayer printed wiring board made of synthetic resin. Then, based on the control signal from the control section 8, the main shaft to which the chuck 10 is connected rotates, and the drill 1 is rotationally driven and simultaneously lowered in the direction of the arrow 19a. At this time, the lower end surface of the condensing part 15 comes into contact with the workpiece 2, but since the suction body 11 is elastically suspended from the bearing part 10a, the feeding of the drill 1 is not hindered. At the same time, the vacuum source 14 is activated to evacuate in the direction of the arrow 20. Thus, when the drill 1 starts drilling the workpiece 2, chips 3 are generated. Then, the generated chips 3 are shown by the arrow 20
The chips are sucked into the chip collection filter 13 through the condensing section 15, the cylindrical section 16, and the suction pipe 12. By the way, when the chips 3 approach the condenser 15, the infrared rays emitted from the chips 3 are optically amplified by the condenser 15, and the amplified infrared rays are received by the infrared detector 5. and is converted into an electrical signal SA having a voltage value corresponding to the amount of light received (see FIG. 2). This electric signal SA is amplified in the amplifier circuit 6, and the amplified electric signal
SB is output as a binary signal 7. In this binarization circuit 7, the voltage value of the electric signal SB is a threshold value V T
Since it is larger than , the signal SC indicating logical value "0"
is output to the gate circuit 9. This gate circuit 9
During the puncturing period, a puncturing period signal SD with a logical value of "1" is input from the control unit 8. Since the logic value of the signal SC is "0" from the gate circuit 9 into which these signals SC and SD are input, the drilling abnormality signal SE having the logic value "1" is not output. However, during drilling, if the drill 1 is damaged or the chips 3 do not flow out smoothly due to blockage, etc., the amount of infrared light received by the infrared detector 5 will rapidly decrease (arrow 21 in Fig. 2). part). Therefore, the binarization circuit 7 outputs an electrical signal SC having a logical value of “1” to the gate circuit 9. Then,
In the gate circuit 9, the logical product of the signals SC and SD, both of which have a logical value of "1", is taken, and the drilling abnormality signal SE, which has a logical value of "1", is output to the alarm device 9a and the control section 8. Thus, the alarm device 9a emits an alarm sound indicating a drilling abnormality, and at the same time, the control section 8 outputs a control signal to raise the drill 1 in the direction of the arrow 19b and stop its rotation.
以上のように、この実施例の穿孔異常検出装置
は、穿孔により発生する切屑から放射される赤外
線検出量の多寡により穿孔異常を検出するように
しているので、検出精度が向上し、小径のドリル
による穿孔異常あるいは加工物が軟質材料である
ときの穿孔異常も確実に検出することができるよ
うになる。 As described above, the drilling abnormality detection device of this embodiment detects drilling abnormalities based on the amount of detected infrared rays emitted from chips generated by drilling, so the detection accuracy is improved and It is now possible to reliably detect drilling abnormalities caused by or when the workpiece is a soft material.
なお、上記実施例において、２値化回路７の出
力側にインバータを設け、さらに２値化回路７に
ては閾値VT以上の信号を入力すると論理値「１」
の電気信号がインバータに出力されるようにして
もよい。さらに、穿孔異常の判定を例えばマイク
ロコンピユータにより行わせるようにしてもよ
い。さらに、吸入体１１は、軸受部１０ａに取付
けるようにしているが、独立して穿孔位置に設置
するようにしてもよい。さらにまた、吸入体１１
は、ドリル１と同軸に設けることなく、穿孔位置
の吸入開口を近接するようにドリル１側部に添設
するようにしてもよい。 In the above embodiment, an inverter is provided on the output side of the binarization circuit 7, and when a signal equal to or higher than the threshold V T is input to the binarization circuit 7, the logic value becomes "1".
The electrical signal may be output to the inverter. Furthermore, the determination of the drilling abnormality may be performed by, for example, a microcomputer. Furthermore, although the suction body 11 is attached to the bearing portion 10a, it may be installed independently at the drilling position. Furthermore, the inhaler 11
may not be provided coaxially with the drill 1, but may be attached to the side of the drill 1 so as to be close to the suction opening at the drilling position.
本発明の穿孔異常検出装置は、穿孔により発生
した切屑を吸入体により一定方向に排出するよう
にするとともに、排出中の切屑より放出されてい
る赤外線を検出して電気信号に変換し、この電気
信号に基づいて穿孔異常を検出するようにしてい
るので、検出精度が向上し、小径のドリルによる
穿孔異常、あるいは、加工物が例えば合成樹脂な
どの軟質材料の穿孔異常も確実に検出することが
できるようになる。
The drilling abnormality detection device of the present invention discharges chips generated by drilling in a fixed direction by a suction body, detects infrared rays emitted from the chips being discharged, converts them into electrical signals, and generates electrical signals. Since drilling abnormalities are detected based on the signal, detection accuracy is improved and it is possible to reliably detect drilling abnormalities caused by small diameter drills or drilling abnormalities in soft materials such as synthetic resins. become able to.
第１図は本発明の一実施例の穿孔異常検出装置
の全体構成図、第２図は穿孔異常検出を説明する
ためのタイミングチヤートである。
４：吸引部、５：赤外線検出部、１１：吸入
体。１５：集光部。
FIG. 1 is an overall configuration diagram of a drilling abnormality detection device according to an embodiment of the present invention, and FIG. 2 is a timing chart for explaining the drilling abnormality detection. 4: Suction part, 5: Infrared detection part, 11: Inhaler. 15: Light condensing part.
Claims (1)
線の拡散を防止する集光部が形成され上記切屑の
発生部位に上記集光部を当接するように設けられ
た吸入体と、上記切屑を上記吸入体を経由して吸
引する吸引部と、上記吸入体に連通し上記吸引部
に吸引されている切屑から放射される赤外線を受
光し受光量に対応する大きさの電気信号に変換す
る赤外線検出部と、この赤外線検出部から出力さ
れた電気信号に基づいて穿孔異常を判定する異常
判定部とを具備し、この異常判定部は上記赤外線
検出部が受光する赤外線の受光量が減少したとき
穿孔異常を判定することを特徴とする穿孔異常検
出装置。1. A suction body formed at one end with a condensing part for preventing the diffusion of infrared rays emitted from chips generated by drilling, and provided so as to bring the condensing part into contact with the site where the chips are generated; a suction part that suctions through the body; and an infrared detection part that communicates with the suction body and receives infrared rays emitted from the chips sucked into the suction part, and converts the infrared rays into an electrical signal of a magnitude corresponding to the amount of received light. and an abnormality determination section that determines whether there is a drilling abnormality based on the electrical signal output from the infrared detection section, and the abnormality determination section determines whether there is a drilling abnormality when the amount of infrared light received by the infrared detection section decreases. A drilling abnormality detection device characterized by determining.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15860984A JPS6138848A (en) | 1984-07-31 | 1984-07-31 | Abnormal boring detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15860984A JPS6138848A (en) | 1984-07-31 | 1984-07-31 | Abnormal boring detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6138848A JPS6138848A (en) | 1986-02-24 |
| JPS6344495B2 true JPS6344495B2 (en) | 1988-09-05 |
Family
ID=15675443
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15860984A Granted JPS6138848A (en) | 1984-07-31 | 1984-07-31 | Abnormal boring detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6138848A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6369208A (en) * | 1986-09-10 | 1988-03-29 | Matsushita Electric Ind Co Ltd | Ignition coil for internal combution engine |
| JP4833535B2 (en) * | 2004-09-30 | 2011-12-07 | 学校法人同志社 | Drilling machine for printed circuit boards |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57107753A (en) * | 1980-11-08 | 1982-07-05 | Feldmuehle Ag | Method and apparatus for monitoring cutting chip in machine tool |
-
1984
- 1984-07-31 JP JP15860984A patent/JPS6138848A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57107753A (en) * | 1980-11-08 | 1982-07-05 | Feldmuehle Ag | Method and apparatus for monitoring cutting chip in machine tool |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6138848A (en) | 1986-02-24 |
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