JPS6129829B2 - - Google Patents
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- Publication number
- JPS6129829B2 JPS6129829B2 JP9259580A JP9259580A JPS6129829B2 JP S6129829 B2 JPS6129829 B2 JP S6129829B2 JP 9259580 A JP9259580 A JP 9259580A JP 9259580 A JP9259580 A JP 9259580A JP S6129829 B2 JPS6129829 B2 JP S6129829B2
- Authority
- JP
- Japan
- Prior art keywords
- welding
- voltage
- charging
- electrodes
- electricity
- 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
- 238000003466 welding Methods 0.000 claims description 86
- 239000000463 material Substances 0.000 claims description 24
- 239000003990 capacitor Substances 0.000 claims description 20
- 238000003860 storage Methods 0.000 claims description 8
- 230000005611 electricity Effects 0.000 claims 6
- 238000001514 detection method Methods 0.000 claims 1
- 238000004146 energy storage Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 238000011109 contamination Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 238000013021 overheating Methods 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- SYHGEUNFJIGTRX-UHFFFAOYSA-N methylenedioxypyrovalerone Chemical compound C=1C=C2OCOC2=CC=1C(=O)C(CCC)N1CCCC1 SYHGEUNFJIGTRX-UHFFFAOYSA-N 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000005493 welding type Methods 0.000 description 1
Landscapes
- Generation Of Surge Voltage And Current (AREA)
- Arc Welding Control (AREA)
Description
【発明の詳細な説明】
この発明は、抵抗溶接機の制御装置に係り、特
に、蓄勢用コンデンサを使用する静電蓄勢式抵抗
溶接機の制御装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a resistance welding machine, and more particularly to a control device for an electrostatic energy storage type resistance welding machine that uses a capacitor for energy storage.
電子工業における微小回路部品の製造ならびに
それらの素子の相互接続においては、次の理由か
ら静電蓄勢式抵抗溶接機が多用されている。 In the manufacture of microcircuit components and the interconnection of those elements in the electronics industry, electrostatic storage type resistance welding machines are frequently used for the following reasons.
(1) 溶接電流のベース・タイム（通電時間）が短
かいため、溶接材料に与える熱影響が小さい。(1) The welding current base time (current application time) is short, so the thermal effect on the welding material is small.
(2) 入力電源の電圧変動に対して、溶接エネルギ
ーの安定化が容易である。(2) It is easy to stabilize welding energy against input power voltage fluctuations.
(3) 省電力形の溶接電源である。(3) It is an energy-saving welding power source.
しかしながら、この溶接機はその特性上、溶接
変圧器の二次側に流れる電流のベース・タイムが
ほぼ一定であるため、溶接条件の選択範囲が狭い
という欠点があつた。この欠点を低減し、溶接材
料の材質、形状等によつてかわる所要の溶接エネ
ルギー１／２CV2（ここでＣはコンデンサ容量、Ｖは
充電電圧）を正確に制御して、溶接材料に供給す
る方法が特公昭42−24818号公報に開示されてい
る。この方法は、蓄勢用コンデンサの充電電圧Ｖ
の変動の一部を増幅し、その出力を弛張発振器に
接続されたトランジスタに加え、その内部抵抗を
変化させて弛張発振器によるトリガパルスの位相
を変化せしめ、蓄勢用コンデンサの充電電圧が高
くなれば位相が進み、低くなれば位相が遅れるよ
うにし、該弛張発振器より取出されるトリガパル
スをSCRのゲート入力とすることによつて、
SCRの点弧角を制御し蓄勢用コンデンサの充電
電圧を任意の一指定電圧に保つようにしたもので
ある。 However, due to the characteristics of this welding machine, the base time of the current flowing to the secondary side of the welding transformer is almost constant, so there was a drawback that the selection range of welding conditions was narrow. To reduce this drawback, the required welding energy 1/2 CV 2 (where C is the capacitor capacity and V is the charging voltage), which varies depending on the material, shape, etc. of the welding material, is accurately controlled and supplied to the welding material. The method is disclosed in Japanese Patent Publication No. 42-24818. This method is based on the charging voltage V of the energy storage capacitor.
A part of the fluctuation in is amplified and its output is applied to the transistor connected to the relaxation oscillator, and its internal resistance is changed to change the phase of the trigger pulse from the relaxation oscillator, increasing the charging voltage of the energy storage capacitor. By setting the phase to advance if it becomes low, and delaying the phase if it becomes low, and by using the trigger pulse taken out from the relaxation oscillator as the gate input of the SCR,
The firing angle of the SCR is controlled to maintain the charging voltage of the energy storage capacitor at a specified voltage.
このような溶接機によれば、溶接材料に適した
溶接エネルギーを正確に制御して供給できるた
め、溶接材料に対する熱影響を極力抑えながら、
しかも溶接材料の過熱、溶断などの事故を防ぎ、
安定した溶接ができる。しかし、電極先端や溶接
材料表面の酸化、汚れなどによる溶接条件の変化
に適応して溶接エネルギーを制御することはでき
ない。 This type of welding machine can accurately control and supply welding energy suitable for the welding material, thereby minimizing the effects of heat on the welding material.
Moreover, it prevents accidents such as overheating and melting of welding materials,
Stable welding is possible. However, it is not possible to control the welding energy in response to changes in welding conditions due to oxidation or dirt on the electrode tip or the surface of the welding material.
本発明の目的は、静電蓄勢式抵抗溶接機におい
て、上記のような両電極間における状態の変化、
特に電極先端や溶接材料表面の酸化、汚れなどに
左右されることなく、常に最適溶接エネルギーを
溶接材料に供給し、一定品質の溶接部を得ること
を可能にした制御装置を提供するものである。 The purpose of the present invention is to provide an electrostatic storage type resistance welding machine with the above-mentioned change in the state between the two electrodes,
The purpose of this invention is to provide a control device that can constantly supply optimal welding energy to the welding material and obtain a welded part of constant quality, regardless of oxidation or dirt on the electrode tip or the surface of the welding material. .
以下、図面を参照して本発明の詳細につき説明
する。溶接電極間の接触抵抗を検出する方法とし
ては、溶接電極を介して、溶接材料を溶接に至ら
しめない程度の微弱かつ一定の直流電流、例えば
別途設けたコンデンサの放電電流を溶接部に供給
し、その時の両溶接電極間の電圧を測定すれば、
Ｒ＝Ｖ／１（Ｒ：電極間の抵抗値，Ｖ：電極間電圧，
Ｉ：一定の直流電流）から溶接電極間の接触抵抗
値を求めることができる。このようにして測定し
た溶接電極間の電圧波形の一例を第１図に示す。
この図において、縦軸に示す電極間電圧Ｖは、電
流を一定とすれば接触抵抗値の変化に対応（比
例）している。従つて、前述の微弱直流電流を溶
接部に供給して得た溶接電極間電圧を用いて、溶
接電極間の接触抵抗値を求め、その値に適応した
最適溶接エネルギーを溶接材料に供給すれば、一
定品質の溶接部を得ることが可能となる。 Hereinafter, details of the present invention will be explained with reference to the drawings. A method for detecting the contact resistance between welding electrodes is to supply a weak and constant direct current that does not cause the welding material to weld, such as a discharge current from a separately provided capacitor, to the welding part via the welding electrode. , if we measure the voltage between both welding electrodes at that time, we get
The contact resistance value between welding electrodes can be determined from R=V/1 (R: resistance value between electrodes, V: interelectrode voltage, I: constant DC current). An example of the voltage waveform between the welding electrodes measured in this manner is shown in FIG.
In this figure, the interelectrode voltage V shown on the vertical axis corresponds (proportional) to the change in contact resistance value, assuming the current is constant. Therefore, by using the voltage between the welding electrodes obtained by supplying the above-mentioned weak direct current to the welding part, the contact resistance value between the welding electrodes is determined, and the optimal welding energy corresponding to that value is supplied to the welding material. , it becomes possible to obtain a welded part of constant quality.
第２図は、本発明になる静電蓄勢式抵抗溶接機
の制御装置の一実施例を示すブロツク図である。
同図において、１は交流の入力電源であり、溶接
休止時間中に昇圧・整流充電制御回路２によつ
て、溶接に必要なエネルギーをコンデンサ３に蓄
える。この蓄勢されたエネルギーは、溶接時に放
電指令回路４からの指令によつて、瞬時に溶接変
圧器５の一次側に放電され、二次側に大電流を生
じさせる。６および６′は溶接電極であり、７は
溶接材料である。１１は、溶接材料７を溶融する
ことなく、溶接電極６および６′間の接触抵抗を
検出し得る程度の微弱電流を供給するための直流
電源であり、コンデンサ３から溶接材料７に溶接
電流が流される前に、溶接電極６，６′間におけ
る状態を最適溶接条件に維持して、溶接電極６お
よび６′間に一定の微弱直流電流を供給する。な
お、この電源１１として適当な周波数を発生する
高周波電源を用いても、同様の効果を得ることが
できる。溶接電極６および６′には電極間電圧を
検出するためのリード１２および１２′がクリツ
プ等で取り付けられている。リード１２および１
２′によつてピツクアツプされた電極間電圧は、
演算増幅器１３に入力され増幅されたのち、アナ
ログ−デジタル変換のためにＡ／Ｄ変換器１４に
出力される。Ａ／Ｄ変換された電圧信号は、スイ
ツチ１５を経て記憶器１６に記憶される。記憶器
１６としては、例えば磁気メモリまたは半導体メ
モリが使用できる。比較器１７においては、記憶
器１６に記憶されている最適溶接条件下における
電圧と、その後の溶接過程中において、溶接電流
を溶接部に供給する前に微弱電流を流して得た電
極間電圧とを比較する。この差電圧値が溶接電極
６および６′間の接触抵抗値の変化量を示すもの
である。ちなみに両電極間が汚れて（電極自体お
よび溶接材料の汚れ）接触抵抗が大きくなつた場
合に、最適溶接条件下における溶接電流と同一溶
接電流を投入するとオーバーヒートにより、場合
によつては溶接材料７が爆飛する。このような不
都合を解消するため、溶接電極６および６′間の
接触抵抗値の変化量に対応する差電圧の値によ
り、コンデンサの充電エネルギーを調整する。即
ち、その後の溶接過程中における電極間電圧が記
憶器１６の電極間電圧よりも大きい場合は、両電
極間の汚れによる接触抵抗の増大を意味するので
充電エネルギーを下げ、逆に小さい場合には充電
エネルギーを上げる。本実施例においては、この
差電圧値を、Ａ／Ｄ変換器１８によつてデジタル
ーアナログ変換して演算器１９に出力し、演算器
１９ではＡ／Ｄ変換器１８からの入力と、昇圧・
整流充電制御回路２に付設されている充電電圧調
整用可変抵抗器２０からの初期設定されているコ
ンデンサ充電電圧設定用出力電圧とから、溶接材
料７の溶接に最適なコンデンサ３の充電電圧指定
信号を演算する。この演算は、接触抵抗値に対応
して充電電圧調整用可変抵抗器２０のコンデンサ
充電電圧設定用出力電圧を修正するために必要な
利得（gain）を実験的に定めてこれを初期設定さ
れているコンデンサ充電電圧設定用出力電圧に加
算または減算するか、接触抵抗値に対応した最適
充電電圧を得るために必要な充電電圧変更値を実
験的に定めて、これをもに用意された接触抵抗値
−充電電圧変更値テーブルから、測定した接触抵
抗値に対応する充電電圧変更値を選択し、これを
初期設定されているコンデンサ充電電圧設定用出
力電圧に加算または減算することによつて行われ
る。この演算器１９の出力によつて、昇圧整流充
電制御回路２の、例えば前記特公昭42−24818号
公報に開示されたごとき、SCRのゲート入力た
るトリガパルスを出力する弛張発振器に接続され
たトランジスタの内部抵抗を変化させて、コンデ
ンサ３に最適溶接エネルギーを充電する。 FIG. 2 is a block diagram showing an embodiment of a control device for an electrostatic storage type resistance welding machine according to the present invention.
In the figure, reference numeral 1 denotes an AC input power source, and energy necessary for welding is stored in a capacitor 3 by a boosting/rectifying charging control circuit 2 during welding down time. This stored energy is instantaneously discharged to the primary side of the welding transformer 5 in response to a command from the discharge command circuit 4 during welding, producing a large current on the secondary side. 6 and 6' are welding electrodes, and 7 is a welding material. 11 is a DC power supply for supplying a weak current that can detect the contact resistance between the welding electrodes 6 and 6' without melting the welding material 7; Before flowing, a constant weak DC current is supplied between the welding electrodes 6 and 6' while maintaining the state between the welding electrodes 6 and 6' at the optimum welding condition. Note that the same effect can be obtained even if a high frequency power source that generates an appropriate frequency is used as the power source 11. Leads 12 and 12' for detecting the voltage between the electrodes are attached to the welding electrodes 6 and 6' by clips or the like. Leads 12 and 1
The interelectrode voltage picked up by 2' is
After being input to the operational amplifier 13 and amplified, the signal is output to the A/D converter 14 for analog-to-digital conversion. The A/D converted voltage signal is stored in the memory 16 via the switch 15. As the memory device 16, for example, a magnetic memory or a semiconductor memory can be used. The comparator 17 compares the voltage under the optimal welding conditions stored in the memory 16 with the interelectrode voltage obtained by passing a weak current before supplying the welding current to the welding part during the subsequent welding process. Compare. This differential voltage value indicates the amount of change in contact resistance value between welding electrodes 6 and 6'. By the way, if the contact resistance increases due to dirt between the two electrodes (contamination of the electrode itself and the welding material), if the same welding current as under the optimum welding conditions is applied, overheating may occur and the welding material may explodes. In order to eliminate this inconvenience, the charging energy of the capacitor is adjusted by the value of the differential voltage corresponding to the amount of change in the contact resistance value between the welding electrodes 6 and 6'. That is, if the inter-electrode voltage during the subsequent welding process is larger than the inter-electrode voltage of the memory device 16, this means an increase in contact resistance due to contamination between both electrodes, so the charging energy is lowered; Increase charging energy. In this embodiment, this differential voltage value is digital-to-analog converted by the A/D converter 18 and output to the arithmetic unit 19, and the arithmetic unit 19 converts the input from the A/D converter 18 and the・
From the initially set output voltage for capacitor charging voltage setting from the charging voltage adjustment variable resistor 20 attached to the rectifier charging control circuit 2, a charging voltage designation signal for the capacitor 3 that is optimal for welding the welding material 7 is determined. Calculate. This calculation is performed by experimentally determining the gain necessary to modify the capacitor charging voltage setting output voltage of the charging voltage adjusting variable resistor 20 in accordance with the contact resistance value, Either add or subtract from the output voltage for setting the capacitor charging voltage, or experimentally determine the charging voltage change value necessary to obtain the optimal charging voltage corresponding to the contact resistance value, and then set this value to the contact resistance value. This is done by selecting the charging voltage change value corresponding to the measured contact resistance value from the value-charging voltage change value table and adding or subtracting this value to the initially set output voltage for setting the capacitor charging voltage. . Based on the output of the arithmetic unit 19, a transistor connected to a relaxation oscillator of the step-up rectifier charging control circuit 2, which outputs a trigger pulse serving as the gate input of the SCR, as disclosed in the above-mentioned Japanese Patent Publication No. 42-24818, for example. The capacitor 3 is charged with the optimum welding energy by changing the internal resistance of the capacitor 3.
具体的一実施例を示すと、厚さ0.1mm×幅
0.7mmのニツケルリボン同志を最適溶接条件下に
おき、容量が1500μＦのコンデンサ100Vに充電
して通電し電極間の接触抵抗値を測定したとこ
ろ、電極間電圧v1＝0.95V、電流ｉ＝370Aとか
ら、接触抵抗値R1＝2.57mΩを得た。次いで、こ
の最適溶接条件下でスポツト溶接したときに十分
な強度が得られた際のコンデンサ充電電圧はV1
＝223Vであつた。 To give a specific example, thickness 0.1mm x width
When 0.7 mm nickel ribbons were placed together under optimal welding conditions, a capacitor with a capacity of 1500 μF was charged at 100 V, and current was applied, the contact resistance between the electrodes was measured. Voltage between the electrodes v 1 = 0.95 V, current i = 370 A. From this, a contact resistance value R 1 =2.57 mΩ was obtained. Next, when sufficient strength is obtained when spot welding is performed under these optimal welding conditions, the capacitor charging voltage is V1.
= 223V.
一方、同一材料で表面に汚れがあるものの接触
抵抗値はR2＝6.12mΩであり、この条件下でスポ
ツト溶接したときに十分な強度が得られた際のコ
ンデンサ充電電圧はV2＝215Vであつた。 On the other hand, the contact resistance value of the same material with dirt on the surface is R 2 = 6.12 mΩ, and the capacitor charging voltage when sufficient strength is obtained when spot welding under these conditions is V 2 = 215 V. It was hot.
従つて、この場合の前記テーブルに格納するデ
ータは、両接触抵抗値の差R2−R1＝6.12−2.57＝
3.55mΩの値と、これに対応する充電電圧変更値
V2−V1＝215−223＝−8Vが格納される。 Therefore, the data stored in the table in this case is the difference between both contact resistance values R 2 −R 1 =6.12−2.57=
3.55mΩ value and corresponding charging voltage change value
V 2 −V 1 =215−223=−8V is stored.
以上の動作により、本発明になる静電蓄勢式抵
抗溶接機の制御装置は、溶接材料の内部抵抗だけ
でなく、溶接電極自体および溶接材料の汚れによ
る溶接条件の変化に適応して、常に溶接エネルギ
ーを最適値に制御することができる。従つて、溶
接材料に対する熱影響を極力抑えながら、しかも
溶接材料の過熱、溶断などの事故を防ぎ、常に一
定品質の溶接部を得ることができる。 Through the above-described operation, the control device for the electrostatic storage type resistance welding machine according to the present invention adapts not only to the internal resistance of the welding material but also to changes in welding conditions due to contamination of the welding electrode itself and the welding material. Welding energy can be controlled to an optimal value. Therefore, it is possible to always obtain a welded part of constant quality while suppressing the thermal influence on the welding material as much as possible, while also preventing accidents such as overheating and melting of the welding material.
第１図は溶接電極間の接触抵抗と電圧との関係
を示す電圧波形図、第２図は本発明になる静電蓄
勢式抵抗溶接機の制御装置の一実施例を示すブロ
ツク図である。
１……交流入力電源、２……昇圧・整流充電制
御回路、３……コンデンサ、４……放電指令回
路、５……溶接変圧器、６・６′……溶接電極、
７……溶接材料、１１……微弱直流電源、１２・
１２′……リード、１３……演算増幅器、１４…
…Ａ／Ｄ変換器、１５……スイツチ、１６……記
憶器、１７……比較器、１８……Ｄ／Ａ変換器、
１９……演算器、２０……充電電圧調整用可変抵
抗器。
FIG. 1 is a voltage waveform diagram showing the relationship between contact resistance between welding electrodes and voltage, and FIG. 2 is a block diagram showing an embodiment of a control device for an electrostatic storage type resistance welding machine according to the present invention. . 1... AC input power supply, 2... Boost/rectification charging control circuit, 3... Capacitor, 4... Discharge command circuit, 5... Welding transformer, 6/6'... Welding electrode,
7... Welding material, 11... Weak DC power supply, 12.
12'... Lead, 13... Operational amplifier, 14...
...A/D converter, 15...Switch, 16...Memory, 17...Comparator, 18...D/A converter,
19... Arithmetic unit, 20... Variable resistor for charging voltage adjustment.
Claims (1)
圧に充電し維持し得る充電制御手段を備えた静電
蓄勢式抵抗溶接機において、溶接電流を溶接材料
に供給する前に２つの電極間にある溶接材料を最
適溶接条件に維持してこの両電極間の接触抵抗ま
たは電圧たる電気量を検出する手段と、この検出
した電気量の所望の形態に加工して記憶する手段
と、その後の溶接時に前記電気量検出手段にて検
出した両電極間の電気量を前記の記憶された値と
比較して両電気量の差を得る手段と、この電気量
の差を表わす信号から充電電圧変更値を選択して
前記充電制御手段の充電電圧指定信号とから、あ
らたに指定すべき充電電圧を求めて充電制御手段
に出力する演算手段とからなることを特徴とする
静電蓄勢式抵抗溶接機の制御装置。1. In an electrostatic storage type resistance welding machine equipped with a charging control means capable of charging and maintaining the electrostatic storage capacity of a capacitor to an appropriate specified charging voltage, the voltage between two electrodes is means for maintaining the welding material under optimal welding conditions and detecting the quantity of electricity, which is the contact resistance or voltage between the two electrodes; means for processing and storing the detected quantity of electricity in a desired form; means for comparing the amount of electricity between the two electrodes detected by the amount of electricity detection means during welding with the stored value to obtain a difference between the two amounts of electricity; and changing the charging voltage from a signal representing the difference in the amount of electricity. Electrostatic storage type resistance welding, characterized in that it is comprised of arithmetic means for selecting a value and calculating a new charging voltage to be specified from the charging voltage designation signal of the charging control means and outputting it to the charging control means. Machine control device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9259580A JPS5719190A (en) | 1980-07-09 | 1980-07-09 | Control device for electrostatic accumulation type resistance welding machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9259580A JPS5719190A (en) | 1980-07-09 | 1980-07-09 | Control device for electrostatic accumulation type resistance welding machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5719190A JPS5719190A (en) | 1982-02-01 |
| JPS6129829B2 true JPS6129829B2 (en) | 1986-07-09 |
Family
ID=14058795
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9259580A Granted JPS5719190A (en) | 1980-07-09 | 1980-07-09 | Control device for electrostatic accumulation type resistance welding machine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5719190A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104209628B (en) * | 2014-09-23 | 2016-08-24 | 上海通用重工集团有限公司 | A kind of concret iron electroslag pressure welder |
-
1980
- 1980-07-09 JP JP9259580A patent/JPS5719190A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5719190A (en) | 1982-02-01 |
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