JPH01228797A - Hole processing method for laminated plate and device therefor - Google Patents
Hole processing method for laminated plate and device thereforInfo
- Publication number
- JPH01228797A JPH01228797A JP63057246A JP5724688A JPH01228797A JP H01228797 A JPH01228797 A JP H01228797A JP 63057246 A JP63057246 A JP 63057246A JP 5724688 A JP5724688 A JP 5724688A JP H01228797 A JPH01228797 A JP H01228797A
- Authority
- JP
- Japan
- Prior art keywords
- stripper
- die
- laminated plate
- hole
- punch
- 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.)
- Granted
Links
- 238000003672 processing method Methods 0.000 title description 2
- 239000000463 material Substances 0.000 claims abstract description 20
- 238000005520 cutting process Methods 0.000 claims abstract description 18
- 229920000049 Carbon (fiber) Polymers 0.000 claims abstract description 14
- 239000004917 carbon fiber Substances 0.000 claims abstract description 14
- 239000002985 plastic film Substances 0.000 claims abstract description 11
- 229920006255 plastic film Polymers 0.000 claims abstract description 11
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000003822 epoxy resin Substances 0.000 claims abstract description 5
- 229920000647 polyepoxide Polymers 0.000 claims abstract description 5
- 230000000452 restraining effect Effects 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 4
- 238000005553 drilling Methods 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 3
- 238000003754 machining Methods 0.000 claims description 2
- 239000004918 carbon fiber reinforced polymer Substances 0.000 abstract description 16
- 238000004080 punching Methods 0.000 abstract description 8
- 239000000543 intermediate Substances 0.000 abstract 1
- 239000002893 slag Substances 0.000 description 5
- 238000007796 conventional method Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
Landscapes
- Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
- Laminated Bodies (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は、中間層にカーボンファイバとエポキシ樹脂か
らなるプリフレグを有してその一方の外層と他方の外層
にプラスチックフィルムを有する積層板（以下、これを
ＣＦＲＰ積層板という。）、の穴加工方法とその装置に
関するものである。Detailed Description of the Invention [Industrial Application Field] The present invention relates to a laminate (hereinafter referred to as "laminated board") having a pre-freg made of carbon fiber and epoxy resin as an intermediate layer and having a plastic film as one outer layer and the other outer layer. , which is called a CFRP laminate), and a device therefor.
［従来の技術］
従来のＣＦＲＰ積層板の穴加工方法は、たとえば、第１
１図に示すように、ＣＦＲＰ積層板４をダイ１２とスト
リッパ１３で挟持し、エツジの刃先をもつパンチ工具１
１をダイ１２に対向させて打ち抜いていた。[Prior Art] A conventional method for drilling holes in a CFRP laminate includes, for example, the first
As shown in Figure 1, a CFRP laminate 4 is held between a die 12 and a stripper 13, and a punch tool 1 with an edge cutting edge is formed.
1 was punched out facing die 12.
［発明が解決しようとする課題］
第１１図に示した従来の技術で、第２図に示すようなｃ
Ｆ ＲＰ ａ層板４に穴加工をした場合、中間層にカ
ーボンファイバとエポキシ樹脂からなるプリフレグ４ａ
の部分は塑性変形しないため、パンチ工具刃先やダイ刃
先が材料に食い込むと、圧縮荷重により加工中にカーボ
ンファイバが砕け、両側外層のプラスチックフィルム４
ｂ、４ｃと中間層が平滑な面に切断されない。また大向
に砕けたカーボンファイバが残り、滓となる。これは第
７図に示すように、プラスチックフィルム４ｂ、４ｃが
切れないで、中心のプリフレグ４ａの部分が凹み、砕け
たカーボンファイバが切断面に残り、滓４ｄが発生する
。この穴が製品の一部に使われる場合、穴径精度不良に
よる組立不良、カーボンの滓によるごみの発生が考えら
れ、製品として使用できないという問題点がある。[Problem to be solved by the invention] In the conventional technology shown in FIG. 11, c as shown in FIG.
When a hole is drilled in the FRP a-layer plate 4, a pre-freg 4a made of carbon fiber and epoxy resin is inserted into the intermediate layer.
Since the part 4 does not undergo plastic deformation, if the punch tool edge or die edge digs into the material, the carbon fiber will break during processing due to the compressive load, and the plastic film 4 on the outer layer on both sides will break.
b, 4c and the intermediate layer are not cut into smooth surfaces. In addition, broken carbon fibers remain in Omukai and become slag. This is because, as shown in FIG. 7, the plastic films 4b and 4c are not cut, and the central pre-freg 4a is depressed, and the broken carbon fibers remain on the cut surface, producing dregs 4d. If this hole is used in a part of a product, there are problems such as poor assembly due to poor hole diameter accuracy and generation of dust due to carbon slag, making it impossible to use the product as a product.
本発明は、このような問題点を解決しようとするもので
ある。すなわち、本発明は、ＣＦＲＰ積層板に高精度の
穴をあけることがで籾る穴加工方法とその装置を提供す
ることを目的とするものである。The present invention attempts to solve these problems. That is, an object of the present invention is to provide a hole processing method and an apparatus for making holes in a CFRP laminate with high precision.
［課題を解決するための手段］
上記目的を達成するために、本発明の方法は、ダイとス
トリッパの間で穴加工される材料である（：ＦＲＰ積層
板を挟持し、かつ、加工される穴周りの該積層板の拘束
力を５０ｋｇ／ｃｍ”以上にし、しかも、刃先をテーパ
付きと段付きのいずれかにしたパンチ工具を用いて打ち
抜くようにした。また本発明の装置は、上面にダイを取
付けている下型ダイセットと、下面にパンチホルダを取
付けている上型ダイセットと、前記パンチホルダの下位
にコイルスプリングを介して取付けられているストリッ
パと、前記パンチホルダに保持されて先端が該ストリッ
パに向いているパンチ工具とからなり、かつ、前記パン
チ工具の刃先がテーパ付きと段付きのいずれかになって
いるとともに、前記コイルスプリングの押圧力を該ダイ
とストリッパの間で挟持されて穴加工されるＣＦＲＰ積
層板の穴周りの拘束力が５０ｋｇ／ｃｍ２以上になるよ
うにした。[Means for Solving the Problems] In order to achieve the above object, the method of the present invention provides a material that is processed with holes between a die and a stripper. The binding force of the laminated plate around the hole is set to 50 kg/cm or more, and punching is performed using a punch tool having either a tapered or stepped cutting edge. A lower die set to which the die is attached, an upper die set to which a punch holder is attached to the lower surface, a stripper attached to the lower part of the punch holder via a coil spring, and a stripper held by the punch holder. a punch tool with a tip facing the stripper, and the cutting edge of the punch tool is either tapered or stepped, and the pressing force of the coil spring is applied between the die and the stripper. The restraining force around the hole of the CFRP laminate that is held and drilled was set to be 50 kg/cm2 or more.
［作 用コ
本発明によれば、パンチ工具の刃先がテーパ付きまたは
段付きとなっているので、ＣＦＲＰ積層板の穴加工され
る中心部が、その刃先によって曲げられ、内部のカーボ
ンファイバが折られたのち、パンチ工具とダイの切刃に
より、外層のプラスチックフィルムを切断し、製品と滓
とに分離される。このとき、材料の拘束力が５０ｋｇ／
ｃｍ”であるため、材料が引っ張られることがなく、穴
が径小や楕円になることがなく、精度の高い穴加工がで
きる。[Function] According to the present invention, since the cutting edge of the punch tool is tapered or stepped, the central part of the CFRP laminate where the hole is to be drilled is bent by the cutting edge, and the carbon fibers inside are bent. After that, the outer plastic film is cut using a punch tool and the cutting edge of the die to separate the product and the slag. At this time, the binding force of the material is 50 kg/
cm'', the material is not stretched, the hole does not become small in diameter or oval, and highly accurate hole processing is possible.
［実施例］ 第１図は本発明の装置の第１実施例を示している。[Example] FIG. 1 shows a first embodiment of the device according to the invention.
第１図において、１は打ち抜き工具である刃先がテーパ
となっているパンチ工具、２は打ち抜き工具であるダイ
、３は材料を押えて拘束するストリッパ、４は材料であ
るＣＦＲＰ積層板である。In FIG. 1, numeral 1 is a punch tool with a tapered cutting edge; 2 is a die, which is a punching tool; 3 is a stripper that presses and restrains the material; and 4 is a CFRP laminate as a material.
第２図はＣＦＲＰ積層板４の構成を示しており、同図に
おいて、４ａはカーボンファイバとエポキシ樹脂からな
るプリフレグ、４ｂ、４ｃはプラスチックフィルムであ
る。FIG. 2 shows the structure of the CFRP laminate 4, in which 4a is a pre-freg made of carbon fiber and epoxy resin, and 4b and 4c are plastic films.
前記プリフレグ４ａは、厚さ０．０２〜０．２ｍｍで、
カーボンファイバの方向性をもち、直交させて重ねるこ
とにより、第３図に示すように多層構成になることもあ
る。The pre-freg 4a has a thickness of 0.02 to 0.2 mm,
Carbon fibers have directionality and can be stacked orthogonally to form a multilayer structure as shown in FIG. 3.
第４図は第１図の装置の全体を示し、第５図は同じくパ
ンチ工具１の形状と寸法を示しており、第６図は同じく
ストリッパ３の形状と寸法を示しており、いずれも、Ｃ
ＦＲＰ積層板４に直径１ｍｍ（φ１．０００）の穴加工
をする場合の例である。すなわち、第５図にみられる刃
先テーパ角θにより穴の切断面状態や穴径寸法精度は大
きく変化する。また穴周りの材料の拘束力も穴の切断面
や穴径に影響を与える。前記テーパ角θの大きさは９Ｑ
”〜１５０°の範囲で、材料拘束力は５０ｋｇ／ｃｍ２
以上で、良好な切断面を得ることができる。FIG. 4 shows the entire apparatus of FIG. 1, FIG. 5 also shows the shape and dimensions of the punch tool 1, and FIG. 6 similarly shows the shape and dimensions of the stripper 3. C
This is an example of drilling a hole with a diameter of 1 mm (φ1.000) in the FRP laminate 4. That is, the state of the cutting surface of the hole and the accuracy of the hole diameter change greatly depending on the taper angle θ of the cutting edge as shown in FIG. In addition, the restraining force of the material around the hole also affects the cut surface and hole diameter of the hole. The size of the taper angle θ is 9Q
“In the range of ~150°, the material restraint force is 50kg/cm2
With the above steps, a good cut surface can be obtained.
第１図において、パンチ工具１とストリッパ３がプレス
により降下すると、ＣＦＲＰ積層板４はストリッパ３に
より押えられ、のちに、パンチ工具１の刃先によって曲
げられ、カーボンファイバが折られたのち、パンチ工具
１とダイ２の切刃によりプラスチックフィルム４ｂ、４
ｃを切断し、製品と滓に分離される。In FIG. 1, when the punch tool 1 and the stripper 3 are lowered by the press, the CFRP laminate 4 is pressed by the stripper 3, and is later bent by the cutting edge of the punch tool 1 to break the carbon fiber, and then 1 and the cutting blades of the die 2 cut the plastic films 4b, 4.
C is cut and separated into product and slag.
このとぎ、材料の拘束力、つまりＣＦＲＰ積層板４を押
さえている力が小さいと、カーボンファイバが折り曲げ
られる時に、材料が引っ張られて滑り、穴が径小や楕円
になることがある。しかし、本発明の方法により得られ
た穴の切断面は第８図にみられるように、平滑で、穴径
絹＋０・０１４）となる。このときの加
変はＨ８（φ１゜
工条件は、（：ＦＲＰ積層板４の板厚が０．１ｍｍ 、
テーパ角θが１４０” 、材料拘束力が３００ ｋｇ／
ｃｍ”、工具クリアランスが５μｍであった。ＣＦＲＰ
積層板４の打ち抜き用工具のクリアランスはその材厚の
３％〜５％がよい。At this time, if the restraining force of the material, that is, the force holding down the CFRP laminate 4 is small, when the carbon fiber is bent, the material may be pulled and slip, causing the hole to become small in diameter or oval. However, as shown in FIG. 8, the cut surface of the hole obtained by the method of the present invention is smooth and has a hole diameter of +0.014). The change at this time is H8 (φ1°) The processing conditions are (: The thickness of the FRP laminate 4 is 0.1 mm,
Taper angle θ is 140”, material restraining force is 300 kg/
cm”, tool clearance was 5 μm. CFRP
The clearance of the punching tool for the laminate 4 is preferably 3% to 5% of the material thickness.
パンチ工具１のテーパ加工は、第９図のように、砥石８
で成形する。また穴周りの材料の拘束力を上げるため、
第６図のように、ストリッパ３に凸状部３ａを設けて、
材料を押える面積を縮小し、そのストリッパ３でコイル
スプリング６により材料を押えつける。なお第６図に示
すようなストリッパ３の加工は放電加工により行なうが
よい。Taper processing of the punch tool 1 is performed using a grindstone 8 as shown in FIG.
Shape with. In addition, to increase the binding force of the material around the hole,
As shown in FIG. 6, the stripper 3 is provided with a convex portion 3a,
The area for pressing the material is reduced, and the stripper 3 presses the material using a coil spring 6. The stripper 3 as shown in FIG. 6 is preferably machined by electric discharge machining.
第１０図はパンチ工具１の第２実施例を示している。こ
の実施例では、パンチ工具１の刃先を段付きにしたもの
で、このようにしても、同様な結果が得られた。FIG. 10 shows a second embodiment of the punch tool 1. In this example, the cutting edge of the punch tool 1 was stepped, and similar results were obtained even with this arrangement.
［発明の効果］
以上説明したように、本発明によれば、パンチ工具の刃
先がテーパ付きまたは段付きになっているので、材料で
あるＣＦＲＰ積層板の穴加工される中心部が、その刃先
によって曲げられ、内部のカーボンファイバが折られた
のち、パンチ工具とダイの切刃により、外層のプラスチ
ックフィルムを切断し、製品と滓とに分離される。[Effects of the Invention] As explained above, according to the present invention, the cutting edge of the punch tool is tapered or stepped, so that the center part of the CFRP laminate, which is the material, where the hole is to be drilled, is aligned with the cutting edge. After the internal carbon fibers are broken, the outer plastic film is cut using a punch tool and the cutting edge of a die, separating the product and the slag.
このとき、材料の拘束力が５０ｋｇ／ｃｍ’以上である
ため、材料が引っ張られることがなく、穴が径小や楕円
になることがなく、精度の高い穴加工ができる。したが
って、これにより、穴を利用した組立、たとえば、かし
め位置決めなどの精度が向上し、自動化が容易になる。At this time, since the restraining force of the material is 50 kg/cm' or more, the material is not stretched, the hole does not become small in diameter or oval, and highly accurate hole processing is possible. Therefore, this improves the accuracy of assembly using holes, such as caulking positioning, and facilitates automation.
第１図は本発明の装置の第１実施例を示した断面図、第
２図はＣＦＲＰ積層板の一例を示した断面図、第３図は
同じくもう１つの例を示した断面図、第４図は第１図の
装置の全体を示した断面図、第５図は第１図のパンチ工
具を示した正面図、第６図は同じくストリッパを示した
断面図、第７図は従来の技術によって穴加工したときの
切断面図、第８図は本発明によって穴加工したしとき切
断面図、第９図は第１図のパンチ工具のテーパ加工の一
例を示した説明図、第１０図は本発明に使用するパンチ
工具の第２実施例を示した正面図、第１１図は従来の技
術の一例を示した断面図である。
１・・・パンチ工具 ２・・・ダイ３・・・スト
リッパ ４・・・ＣＦＲＰ積層板４ａ・・・プリ
フレグ
４ｂ、４ｃ・・・プラスチックフィルム５・・・パンチ
ホルダ ６・・・コイルスプリング７ａ・・・上型
ダイセット ７ｂ・・・下型ダイセット８・・・砥石
第１図
第４図 第５図FIG. 1 is a sectional view showing a first embodiment of the apparatus of the present invention, FIG. 2 is a sectional view showing an example of a CFRP laminate, FIG. 3 is a sectional view showing another example, and FIG. Fig. 4 is a sectional view showing the entire device of Fig. 1, Fig. 5 is a front view showing the punch tool of Fig. 1, Fig. 6 is a sectional view also showing the stripper, and Fig. 7 is a conventional FIG. 8 is a cross-sectional view of a hole formed by the technique, FIG. 8 is a cross-sectional view of a hole formed by the present invention, FIG. 9 is an explanatory view showing an example of taper processing of the punch tool of FIG. 1, and FIG. The figure is a front view showing a second embodiment of the punch tool used in the present invention, and FIG. 11 is a sectional view showing an example of the conventional technique. 1... Punch tool 2... Die 3... Stripper 4... CFRP laminate 4a... Pre-flag 4b, 4c... Plastic film 5... Punch holder 6... Coil spring 7a. ...Upper die set 7b...Lower die set 8...Whetstone Fig. 1 Fig. 4 Fig. 5
Claims (1)
間層にカーボンファイバとエポキシ樹脂からなるプリフ
レグを有してその一方の外層と他方の外層とにプラスチ
ックフィルムを有する積層板を挟持し、かつ、加工され
る穴周りの該積層板の拘束力を５０ｋｇ／ｃｍ＾２以上
にし、しかも、刃先をテーパ付きと段付きのいずれかに
したパンチ工具を用いて打ち抜くことを特徴とする積層
板の穴加工方法。 ２ 上面にダイを取付けている下型ダイセットと、下面
にパンチホルダを取付けている上型ダイセットと、前記
パンチホルダの下位にコイルスプリングを介して取付け
られているストリッパと、前記パンチホルダに保持され
て先端が該ストリッパに向いているパンチ工具とからな
り、かつ、前記パンチ工具の刃先がテーパ付きと段付き
のいずれかになっているとともに、前記コイルスプリン
グの押圧力を該ダイとストリッパの間で挟持されて穴加
工される積層板の穴周りの拘束力が５０ｋｇ／ｃｍ＾２
以上になるようにしたことを特徴とする積層板の穴加工
装置。[Claims] 1. A laminate having a pre-freg made of carbon fiber and epoxy resin in the intermediate layer, which is the material to be drilled between the die and the stripper, and having a plastic film as one outer layer and the other outer layer. Hold the plate, make the restraining force of the laminate around the hole to be machined 50 kg/cm^2 or more, and punch using a punch tool with either a tapered or stepped cutting edge. Features a method for drilling holes in laminates. 2. A lower die set with a die attached to the upper surface, an upper die set with a punch holder attached to the lower surface, a stripper attached to the lower part of the punch holder via a coil spring, and a stripper attached to the punch holder. a punch tool that is held and has its tip facing the stripper, and the cutting edge of the punch tool is either tapered or stepped, and the pressing force of the coil spring is applied to the die and the stripper. The restraining force around the hole of the laminate plate which is sandwiched between the holes and drilled is 50kg/cm^2
A hole machining device for a laminate board characterized by the above-mentioned features.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63057246A JPH0632918B2 (en) | 1988-03-10 | 1988-03-10 | Method and device for drilling holes in laminated plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63057246A JPH0632918B2 (en) | 1988-03-10 | 1988-03-10 | Method and device for drilling holes in laminated plate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01228797A true JPH01228797A (en) | 1989-09-12 |
| JPH0632918B2 JPH0632918B2 (en) | 1994-05-02 |
Family
ID=13050174
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63057246A Expired - Lifetime JPH0632918B2 (en) | 1988-03-10 | 1988-03-10 | Method and device for drilling holes in laminated plate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0632918B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006068836A (en) * | 2004-08-31 | 2006-03-16 | Nagamine Seisakusho:Kk | Punching tool |
| JP2016052682A (en) * | 2011-03-02 | 2016-04-14 | 学校法人日本大学 | Method and apparatus for punching fiber-reinforced plastic plate material |
| CN105666578A (en) * | 2016-03-12 | 2016-06-15 | 安徽佳力奇航天碳纤维有限公司 | Distributing and drilling device for carbon fiber composite material |
| WO2018163411A1 (en) * | 2017-03-10 | 2018-09-13 | 日産自動車株式会社 | Composite material member, method for producing composite material member, and molding die for same |
-
1988
- 1988-03-10 JP JP63057246A patent/JPH0632918B2/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006068836A (en) * | 2004-08-31 | 2006-03-16 | Nagamine Seisakusho:Kk | Punching tool |
| JP2016052682A (en) * | 2011-03-02 | 2016-04-14 | 学校法人日本大学 | Method and apparatus for punching fiber-reinforced plastic plate material |
| US9555466B2 (en) | 2011-03-02 | 2017-01-31 | Nihon University | Substrate joining method using rivet, and joining structure |
| CN105666578A (en) * | 2016-03-12 | 2016-06-15 | 安徽佳力奇航天碳纤维有限公司 | Distributing and drilling device for carbon fiber composite material |
| WO2018163411A1 (en) * | 2017-03-10 | 2018-09-13 | 日産自動車株式会社 | Composite material member, method for producing composite material member, and molding die for same |
| JPWO2018163411A1 (en) * | 2017-03-10 | 2020-02-27 | 日産自動車株式会社 | Composite material member, method of manufacturing composite material member, and mold for molding the same |
| US10864699B2 (en) | 2017-03-10 | 2020-12-15 | Nissan Motor Co., Ltd. | Composite material member, method for producing composite material member, and molding die for same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0632918B2 (en) | 1994-05-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6482490B1 (en) | Printing sheet with base material, and method of manufacturing the same | |
| JPH01228797A (en) | Hole processing method for laminated plate and device therefor | |
| JPS63260631A (en) | Burring forming device | |
| JPH04138824A (en) | Punch for burring | |
| JP3215369B2 (en) | Punch punch and sheet material | |
| JP3242355B2 (en) | Fastening method and fastening structure | |
| JPH0319393A (en) | Manufacture of aluminum insulating board | |
| JP3187103B2 (en) | Fastening method and fastening structure | |
| JP2569866B2 (en) | Press equipment and processing method for burring | |
| DE102010011504A1 (en) | Method for manufacturing transponder antenna for radio frequency identification tag for, e.g. debit card, involves fixing metal foil on antenna support layer, contouring antenna structure, and removing residual structure surrounding foil | |
| JP2511283B2 (en) | Processing method for pressed parts | |
| JPH0851267A (en) | Circuit board and its manufacture | |
| JP3090702B2 (en) | Method of manufacturing electrode structure for electron gun | |
| JP2798478B2 (en) | Connection conductor and method of manufacturing the same | |
| JPH06326239A (en) | Film punching and applying machine for lead frame | |
| JP2001300648A (en) | Piercing method of metal plate | |
| JPH0379299A (en) | Punching method for punch die and tool thereof | |
| JP3112563B2 (en) | Processing method of metal / resin laminate | |
| JPH0439734B2 (en) | ||
| CN115431344A (en) | Die cutting process for side-edge-wrapped graphite | |
| JPH10180694A (en) | Perforator, perforating method and hollow punch | |
| JPH07185686A (en) | Blanking punch | |
| JP2951357B2 (en) | Cutting method of metal composite sheet | |
| JPS6182936A (en) | Method for improving accuracy of sheared cross section in press work | |
| JP2002239995A (en) | Film punching method and die for punching |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |