JPS6224182B2 - - Google Patents
Info
- Publication number
- JPS6224182B2 JPS6224182B2 JP12154582A JP12154582A JPS6224182B2 JP S6224182 B2 JPS6224182 B2 JP S6224182B2 JP 12154582 A JP12154582 A JP 12154582A JP 12154582 A JP12154582 A JP 12154582A JP S6224182 B2 JPS6224182 B2 JP S6224182B2
- Authority
- JP
- Japan
- Prior art keywords
- welding
- circuit
- oscillation
- stop control
- control circuit
- 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 55
- 230000010355 oscillation Effects 0.000 claims description 41
- 230000005764 inhibitory process Effects 0.000 claims description 4
- 238000001514 detection method Methods 0.000 claims description 3
- 239000000463 material Substances 0.000 description 8
- 239000010953 base metal Substances 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/10—Other electric circuits therefor; Protective circuits; Remote controls
Description
【発明の詳細な説明】
この発明は、アーク溶接用電源装置に関し、特
には出力トランスの２次側短絡時（溶接開始時）
に動作を自動的に開始し、２次側開放時（溶接終
了時）に動作を自動的に停止するスイツチング回
路を備えた直流アーク溶接用電源装置に関する。[Detailed Description of the Invention] The present invention relates to a power supply device for arc welding, particularly when the secondary side of an output transformer is short-circuited (at the start of welding).
The present invention relates to a DC arc welding power supply device equipped with a switching circuit that automatically starts operation when the secondary side is opened (when welding ends) and automatically stops operation when the secondary side is opened (when welding is finished).
従来の直流アーク溶接用電源装置のブロツク図
を第１図に示す。商用周波電源１、全波整流器
２、平滑コンデンサ３を介した直流出力は、出力
トランス４の１次側中点タツプとスイツチング回
路５間に供給される。スイツチング回路５は、ス
イツチング素子であるパワートランジスタ５０，
５１がプツシユプル接続されて出力トランス４の
１次側の両側のタツプに接続される。スイツチン
グ回路５の数KHz〜数10KHzオンオフ動作は、
パワートランジスタ５０，５１のベースに接続さ
れた制御回路６によつて与えられる制御信号によ
つて交互に行なわれる。また、制御回路６は、２
次側短絡時（溶接開始時）を検出する発振開始制
御回路１０と、２次側開放時（溶接終了時）を検
出する発振停止制御回路１１とによつて制御され
る。発振停止制御回路１１は２次側出力電圧が所
定の電圧以上であるかどうかを検出するための基
準電圧（図示せず）設定手段を有している。 A block diagram of a conventional DC arc welding power supply device is shown in FIG. A DC output via a commercial frequency power supply 1, a full-wave rectifier 2, and a smoothing capacitor 3 is supplied between the primary side center point tap of an output transformer 4 and a switching circuit 5. The switching circuit 5 includes a power transistor 50, which is a switching element.
51 are connected in a push-pull manner to the taps on both sides of the primary side of the output transformer 4. The on/off operation of switching circuit 5 from several KHz to several tens of KHz is as follows:
This is done alternately by a control signal provided by a control circuit 6 connected to the bases of power transistors 50,51. Further, the control circuit 6 has two
It is controlled by an oscillation start control circuit 10 that detects when the secondary side is shorted (when welding starts) and an oscillation stop control circuit 11 that detects when the secondary side is opened (when welding ends). The oscillation stop control circuit 11 has a reference voltage (not shown) setting means for detecting whether the secondary output voltage is equal to or higher than a predetermined voltage.
この電源装置は次のように動作する。 This power supply operates as follows.
まず商用周波電源１が入力されると、制御回路
６、発振開始制御回路１０、発振停止制御回路１
１にそれぞれ駆動電圧が与えられる。しかしこの
時点では、まだスイツチング回路５は動作しな
い。そこで、溶接電極１４を母材１５に軽く接触
させて離すと、発振開始制御回路１０が直ちに２
次側短絡を検出して、制御回路６の発振を開始さ
せる。それによつて出力トランス４は駆動し、溶
接電極１４と母材１５間にアークが発生する。一
方、溶接作業が完了して溶接電極１４を母材１５
から離すと、溶接出力端子間８，９の電圧は上昇
し、発振停止制御回路１１がその電圧上昇を検出
する。溶接出力端子間８，９の電圧が、発振停止
制御回路１１に予め設定されている所定の設定電
圧を越えると、発振停止制御回路１１は信号を発
して制御回路６の発振を停止させる。 First, when the commercial frequency power supply 1 is input, the control circuit 6, the oscillation start control circuit 10, and the oscillation stop control circuit 1
A driving voltage is applied to each of the signals 1 and 1. However, at this point, the switching circuit 5 does not operate yet. Therefore, when the welding electrode 14 is lightly brought into contact with the base material 15 and then released, the oscillation start control circuit 10 immediately activates the
The next-side short circuit is detected and the control circuit 6 starts oscillating. Thereby, the output transformer 4 is driven, and an arc is generated between the welding electrode 14 and the base material 15. On the other hand, when the welding work is completed, the welding electrode 14 is attached to the base material 15.
When the welding output terminals 8 and 9 are separated from each other, the voltage between the welding output terminals 8 and 9 increases, and the oscillation stop control circuit 11 detects this voltage increase. When the voltage between the welding output terminals 8 and 9 exceeds a predetermined voltage set in the oscillation stop control circuit 11, the oscillation stop control circuit 11 issues a signal to stop the oscillation of the control circuit 6.
上述のように第１図に示す従来の電源装置で
は、溶接作業再開までの間、商用周波電源１が入
つていてもスイツチング回路５が動作しないた
め、制御回路等の無負荷損は生じない利点があ
る。また、無負荷のとき、出力トランス４の鉄心
が磁気飽和することによつて生じる耳ざわりな雑
音も発生しない利点を有している。 As mentioned above, in the conventional power supply device shown in Fig. 1, the switching circuit 5 does not operate even if the commercial frequency power supply 1 is turned on until the welding work is restarted, so no no-load loss occurs in the control circuit, etc. There are advantages. Furthermore, when there is no load, there is an advantage that no harsh noise is generated due to magnetic saturation of the iron core of the output transformer 4.
しかしながら以上のような構成にある従来の直
流アーク溶接用電源装置では、溶接姿勢あるいは
溶接技術の稚拙によつて溶接電極１４と母材１５
の間隔が一時的に大きくなつただけでも、発振停
止制御回路内の基準電圧設定手段の設定位置が適
当でないと、発振停止制御回路１１が動作する場
合がある。このため溶接途中であつてもアーク切
れを起こし、スラグの巻き込み等の溶接不良を引
き起こす欠点があつた。 However, in the conventional DC arc welding power supply device having the above configuration, the welding electrode 14 and base metal 15 may
Even if the interval is only temporarily increased, the oscillation stop control circuit 11 may operate if the setting position of the reference voltage setting means in the oscillation stop control circuit is not appropriate. For this reason, arc breakage occurs even during welding, resulting in welding defects such as slag entrainment.
この発明は上記の欠点に鑑みなされたもので、
溶接作業中は溶接電流が流れている限り、２次側
電圧に変動が生じてもアーク切れを起こさない、
アーク溶接用電源装置の提供を目的とする。 This invention was made in view of the above drawbacks.
During welding work, as long as the welding current is flowing, arc breakage will not occur even if the secondary voltage fluctuates.
The purpose is to provide a power supply device for arc welding.
この発明を要約すれば、２次側に負荷電流が流
れていることを検出する負荷電流検出回路を、２
次側に直接或いは１次側に設け、さらにこの検出
回路で負荷電流を検出しているとき発振停止制御
回路の動作を停止させる発振停止制御禁止回路を
設けたことを特徴とする。 To summarize this invention, a load current detection circuit that detects that a load current is flowing to the secondary side is
The present invention is characterized in that it is provided directly on the next side or on the primary side, and further includes an oscillation stop control prohibition circuit that stops the operation of the oscillation stop control circuit when the load current is detected by this detection circuit.
以下この発明の実施例を図面を参照しながら説
明する。 Embodiments of the present invention will be described below with reference to the drawings.
第２図はこの発明の実施例である直流アーク溶
接用電源装置のブロツク図である。第１図に示し
た従来の直流アーク溶接用電源装置と同一ないし
相当部分については同一番号を付している。 FIG. 2 is a block diagram of a DC arc welding power supply device according to an embodiment of the present invention. Components that are the same or equivalent to those of the conventional DC arc welding power supply device shown in FIG. 1 are given the same numbers.
出力トランス４の２次側は全波整流器７を介し
て溶接出力端子８，９に接続される。一方の溶接
出力端子９には、負荷電流を検出するため適当な
インピーダンス素子からなる負荷電流検出器１６
が設けられる。この負荷電流検出器１６は、スイ
ツチング回路５の発振を停止させる発振停止制御
回路１１と接続された発振停止制御禁止回路１７
に、負荷電流を検出しているとき信号を与える。 The secondary side of the output transformer 4 is connected to welding output terminals 8 and 9 via a full-wave rectifier 7. One of the welding output terminals 9 is equipped with a load current detector 16 consisting of a suitable impedance element to detect the load current.
is provided. This load current detector 16 has an oscillation stop control prohibition circuit 17 connected to an oscillation stop control circuit 11 that stops the oscillation of the switching circuit 5.
A signal is given to the terminal when the load current is being detected.
第３図、第４図は、第２図における各部の構成
を示す回路図である。 3 and 4 are circuit diagrams showing the configuration of each part in FIG. 2.
発振開始制御回路１０は、第３図で示すように
直流電源PS、演算増幅器OP1、抵抗R1，R2、ダ
イオードＤから構成される。交流を入力として直
流を出力する直流電源PSは、基準電圧を出力す
る基準端子K1と基準電圧より高く通常のアーク
電圧より低い電圧を出力する端子K2とを備えて
いる。基準端子K1は演算増幅器OP1の非反転入力
端子に直接接続され、端子K2は抵抗R1，R2を介
して反転入力端子に接続される。この抵抗R1，
R2の接続点にはダイオードＤを介して溶接出力
端子８が接続される。また溶接出力端子９は、発
振開始制御回路１０のアース端子f2に接続され
る。 The oscillation start control circuit 10 is comprised of a DC power supply PS, an operational amplifier OP 1 , resistors R 1 and R 2 , and a diode D, as shown in FIG. A DC power supply PS that receives alternating current as input and outputs direct current includes a reference terminal K1 that outputs a reference voltage and a terminal K2 that outputs a voltage that is higher than the reference voltage and lower than a normal arc voltage. The reference terminal K 1 is directly connected to the non-inverting input terminal of the operational amplifier OP 1 , and the terminal K 2 is connected to the inverting input terminal via resistors R 1 and R 2 . This resistance R 1 ,
A welding output terminal 8 is connected to the connection point of R2 via a diode D. Further, the welding output terminal 9 is connected to the ground terminal f 2 of the oscillation start control circuit 10 .
ここで発振開始制御回路１０の動作説明をす
る。第２図で示す商用周波電源１が投入される
と、第３図の直流電源PSは、基準端子K1、端子
K2にそれぞれ電圧を出力する。しかしこの時点
では溶接電極１４と母材１５は、開放状態にある
ため、端子f1，f2間は電位差がある。この場合、
演算増幅器OP1は非反転入力端子より反転入力端
子の方が高電位であるため、出力端子は論理
“０”である。ここで溶接電極１４と母材１５を
短絡すると、直流電源PSの端子K2から抵抗R1、
ダイオードＤ、端子f1、溶接電極１４、母材１
５、端子f2と電流が流れるため、端子f1，f2間の
電圧は零となる。すると演算増幅器OP1の入力電
圧は、非反転入力端子より反転入力端子の方が低
くなるため、演算増幅器OP1は論理“１”とな
る。この論理“１”の出力は、ダイオード１２を
介して制御回路６に与えられる。それによりスイ
ツチング回路５が発振を開始し、溶接電極１４と
母材１５の間にアークを発生させる。そして、溶
接電極１４と母材１５がある間隔を保たれてアー
クを発生し続けている溶接作業中も、直流電源
PSの端子K2はアークを通して導通されるため、
端子f1，f2間は低電位が保たれ、制御回路６には
論理“１”が入力され続けている。 Here, the operation of the oscillation start control circuit 10 will be explained. When the commercial frequency power supply 1 shown in FIG. 2 is turned on, the DC power supply PS shown in FIG .
Output voltage to K 2 respectively. However, at this point, the welding electrode 14 and the base metal 15 are in an open state, so there is a potential difference between the terminals f 1 and f 2 . in this case,
Since the inverting input terminal of the operational amplifier OP1 has a higher potential than the non-inverting input terminal, the output terminal is logic "0". If welding electrode 14 and base metal 15 are short-circuited here, resistance R 1 will be connected to terminal K 2 of DC power supply PS,
Diode D, terminal f 1 , welding electrode 14, base material 1
5. Since current flows through terminal f 2 , the voltage between terminals f 1 and f 2 becomes zero. Then, since the input voltage of the operational amplifier OP1 is lower at the inverting input terminal than at the non-inverting input terminal, the operational amplifier OP1 becomes logic "1". This logic "1" output is given to the control circuit 6 via the diode 12. As a result, the switching circuit 5 starts oscillating, and an arc is generated between the welding electrode 14 and the base material 15. Even during welding work in which the welding electrode 14 and the base metal 15 are kept at a certain distance and the arc continues to be generated, the DC power supply
Terminal K 2 of PS is conducted through the arc, so
A low potential is maintained between the terminals f 1 and f 2 , and logic “1” continues to be input to the control circuit 6 .
次に発振停止制御回路１１と発振停止制御禁止
回路１７とにつき第４図に基いて説明する。 Next, the oscillation stop control circuit 11 and the oscillation stop control inhibition circuit 17 will be explained based on FIG. 4.
発振停止制御回路１１は、比較器COMP、トラ
ンジスタQ1、基準電圧Ｅから構成される。比較
器COMPの非反転入力端子には２次側無負荷電圧
よりも小さい適当な基準電圧Ｅが与えられ、反転
入力端子には溶接電極１４の電圧（プラス電位）
が与えられる。トランジスタQ1はエミツタ接地
したインバータ回路を構成する。 The oscillation stop control circuit 11 includes a comparator COMP, a transistor Q 1 , and a reference voltage E. An appropriate reference voltage E smaller than the secondary no-load voltage is applied to the non-inverting input terminal of the comparator COMP, and the voltage of the welding electrode 14 (positive potential) is applied to the inverting input terminal.
is given. Transistor Q1 constitutes an inverter circuit whose emitter is grounded.
発振停止制御禁止回路１７は、演算増幅器
OP2、トランジスタQ2およびダイオード１８から
構成される。演算増幅器OP2の反転入力端子は、
負荷電流検出器１６の負側端子に接続され、非反
転入力端子は負荷電流検出器１６の正側端子とと
もに接地される。トランジスタQ2もエミツタ接
地したインバータ回路を構成する。 The oscillation stop control prohibition circuit 17 is an operational amplifier
It consists of OP 2 , transistor Q 2 and diode 18 . The inverting input terminal of operational amplifier OP 2 is
It is connected to the negative terminal of the load current detector 16, and its non-inverting input terminal is grounded together with the positive terminal of the load current detector 16. Transistor Q2 also constitutes an inverter circuit whose emitter is grounded.
次に動作説明をする。 Next, the operation will be explained.
溶接電極１４と母材１５との間隔が一定の範囲
に保たれてアークを発生している溶接作業中は負
荷電流が溶接出力端子８，９間を流れているた
め、演算増幅器OP2の反転入力端子の入力は、非
反転入力端子より低電位にある。したがつて演算
増幅器OP2は、トランジスタQ2をオン状態にす
る。このため、ダイオード１８を介して、そのア
ノード端子を零電位にする。この状態は、発振停
止制御回路１１の状態に無関係に継持される。す
なわち、負荷電流が検出されている限り、発振停
止制御回路１１の動作は禁止される。 During welding work when the distance between the welding electrode 14 and the base metal 15 is maintained within a certain range and an arc is generated, the load current flows between the welding output terminals 8 and 9, so the operational amplifier OP 2 is inverted. The input of the input terminal is at a lower potential than the non-inverting input terminal. Operational amplifier OP 2 therefore turns on transistor Q 2 . Therefore, the anode terminal is brought to zero potential via the diode 18. This state is maintained regardless of the state of the oscillation stop control circuit 11. That is, as long as the load current is detected, the operation of the oscillation stop control circuit 11 is prohibited.
一方、溶接終了時は、溶接電極１４と母材１５
が引き離されて溶接出力端子８，９間の電圧は上
昇するが、負荷電流はなくなるため、トランジス
タQ2はオフして、ダイオード１８のカソードの
電圧は高くなる。これによつて、発振停止制御回
路１１の動作禁止状態が解除されるが、このとき
比較器COMPの反転入力電圧が基準電圧Ｅより大
きくなるため、トランジスタQ1はオフ状態とな
つてダイオード１８のアノード電圧が高くなる。
すなわち、溶接電極１４と母材１５とが引き離さ
れた瞬間にスイツチング回路５の発振が停止する
ことになる。 On the other hand, at the end of welding, the welding electrode 14 and the base material 15
are pulled apart and the voltage between the welding output terminals 8 and 9 increases, but since there is no load current, the transistor Q2 is turned off and the voltage at the cathode of the diode 18 becomes high. As a result, the operation prohibited state of the oscillation stop control circuit 11 is released, but at this time, the inverted input voltage of the comparator COMP becomes larger than the reference voltage E, so the transistor Q 1 is turned off and the diode 18 is turned off. Anode voltage increases.
That is, the oscillation of the switching circuit 5 stops at the moment when the welding electrode 14 and the base material 15 are separated.
なお以上の実施例では、発振停止制御禁止回路
を演算増幅器、トランジスタによつて構成した
が、この発明はこれらの素子に限定されることな
くサイリスタ等の他のスイツチング素子を用いて
もよい。また、負荷電流検出器を実施例では母材
側の端子に設けたが、溶接電極側に設けてもよ
く、さらには１次側に設けてもよい。 In the embodiments described above, the oscillation stop control inhibiting circuit is constituted by an operational amplifier and a transistor, but the present invention is not limited to these elements, and other switching elements such as a thyristor may be used. Further, although the load current detector is provided at the terminal on the base metal side in the embodiment, it may be provided on the welding electrode side, or further, may be provided on the primary side.
以上述べたようにこの発明は、負荷電流検出器
で負荷電流を検出しているとき発振停止制御回路
の動作を停止させる発振停止制御禁止回路を備え
たので、溶接姿勢あるいは溶接技術の稚拙によつ
て溶接電極と母材の間隔が一時的に大きくなつて
も、負荷電流を検出している限り溶接作業中にア
ーク切れを起こさない。したがつて高度な熟練と
工夫が要求される手溶接においても、この発明の
アーク溶接用電源装置を用いることによつて、溶
接技術の巧拙が溶接結果に大きな影響を与えるこ
とはなくなつた。 As described above, the present invention is equipped with an oscillation stop control prohibition circuit that stops the operation of the oscillation stop control circuit when the load current is detected by the load current detector. Therefore, even if the distance between the welding electrode and the base metal becomes temporarily large, arc breakage will not occur during welding as long as the load current is detected. Therefore, even in manual welding which requires a high degree of skill and ingenuity, by using the arc welding power supply device of the present invention, the skill of the welding technique no longer has a large effect on the welding result.
第１図は従来の直流アーク溶接用電源装置のブ
ロツク図、第２図はこの発明の実施例である直流
アーク溶接用電源装置のブロツク図、第３図、第
４図は第２図における各部の構成を示す回路図で
ある。
４…出力トランス、５…スイツチング回路、６
…制御回路、１０…発振開始制御回路、１１…発
振停止制御回路、１４…溶接電極、１５…母材、
１６…負荷電流検出器、１７…発振停止制御禁止
回路。
Fig. 1 is a block diagram of a conventional power supply device for DC arc welding, Fig. 2 is a block diagram of a power supply device for DC arc welding which is an embodiment of the present invention, and Figs. 3 and 4 show various parts in Fig. 2. FIG. 4...Output transformer, 5...Switching circuit, 6
... Control circuit, 10... Oscillation start control circuit, 11... Oscillation stop control circuit, 14... Welding electrode, 15... Base material,
16...Load current detector, 17...Oscillation stop control inhibition circuit.
Claims (1)
２次側に溶接負荷を接続するとともに２次側の短
絡時に前記スイツチング回路の発振動作を開始さ
せる発振開始制御回路と、２次側電圧が所定電圧
以上になつたとき前記スイツチング回路の発振動
作を停止させる発振停止制御回路とを有するアー
ク溶接用電源装置において、 ２次側に負荷電流が流れていることを検出する
負荷電流検出器と、 この検出器が負荷電流を検出しているときにオ
ンして出力をグラウンドレベルに落とし、検出し
ていないときにオフするスイツチ素子、およびこ
のスイツチ素子の出力と前記発振停止制御禁止回
路の出力間に接続され、その出力間を前記スイツ
チ素子がオンしているとき導通する手段を備える
発振停止制御禁止回路とを備えて成るアーク溶接
用電源装置。[Claims] 1. A switching circuit on the primary side of the output transformer,
an oscillation start control circuit that connects a welding load to the secondary side and starts the oscillation operation of the switching circuit when the secondary side is short-circuited; In an arc welding power supply device that has an oscillation stop control circuit that stops the oscillation, there is a load current detector that detects that load current is flowing to the secondary side, and a load current detector that turns on when the load current is detected. a switch element that lowers the output to the ground level and turns off when no detection is being detected, and a switch element that is connected between the output of this switch element and the output of the oscillation stop control inhibition circuit, and that the switch element turns on between the outputs. An oscillation stop control inhibition circuit having means for conducting when the oscillation stop control inhibit circuit is turned on when
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12154582A JPS5913571A (en) | 1982-07-12 | 1982-07-12 | Electric power source device for arc welding |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12154582A JPS5913571A (en) | 1982-07-12 | 1982-07-12 | Electric power source device for arc welding |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5913571A JPS5913571A (en) | 1984-01-24 |
| JPS6224182B2 true JPS6224182B2 (en) | 1987-05-27 |
Family
ID=14813893
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12154582A Granted JPS5913571A (en) | 1982-07-12 | 1982-07-12 | Electric power source device for arc welding |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5913571A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4639541B2 (en) | 2001-03-01 | 2011-02-23 | 株式会社デンソー | Cycle using ejector |
-
1982
- 1982-07-12 JP JP12154582A patent/JPS5913571A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5913571A (en) | 1984-01-24 |
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