DK159011B - Electrical energy source for a resistance welding machine - Google Patents

Electrical energy source for a resistance welding machine Download PDF

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Publication number
DK159011B
DK159011B DK010483A DK10483A DK159011B DK 159011 B DK159011 B DK 159011B DK 010483 A DK010483 A DK 010483A DK 10483 A DK10483 A DK 10483A DK 159011 B DK159011 B DK 159011B
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DK
Denmark
Prior art keywords
frequency
energy source
welding current
output
output alternating
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DK010483A
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Danish (da)
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DK159011C (en
DK10483A (en
DK10483D0 (en
Inventor
Zelimir Belamaric
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Elpatronic Ag
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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
    • B23K11/00—Resistance welding; Severing by resistance heating
    • B23K11/24—Electric supply or control circuits therefor
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Power Engineering (AREA)
  • Generation Of Surge Voltage And Current (AREA)
  • Resistance Welding (AREA)
  • Inverter Devices (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)
  • Adjustable Resistors (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)

Abstract

The electric energy source for a resistance-welder comprises a static reversing device, a welding transformer, and a first static frequency converter (10) comprised of semiconductor elements, of which the output alternating voltage has a frequency and a pulse wave-form different from the frequency and the pulse wave-form of the supply voltage provided to the reversing device. In order to vary on a large range the pulse wave-form, the amplitude and the pulse ratio, the source comprises at least a second frequency converter (11) mounted in parallel on the first frequency converter (10) and of which the output alternating voltage may be added, in phase synchronism, to the output alternating voltage of the first frequency converter (10) in the primary circuit of the welding transformer (12).

Description

DK 159011 BDK 159011 B

Opfindelsen omhandler en elektrisk energikilde med en statisk omformer og en svejsetransformer til en modstandssvejsemaskine, hvor der anvendes en første statisk frekvensomformer, der er opbygget af halvlederelementer, og hvis afgangsvekselspæn-5 ding har halvbølger, der er dannet af impulstog, og hvor svejsestrømshal vbølgerne har et næsten firkantet forløb, som er kendt fra tysk offentliggørelsesskrift nr. 1.613.730.The invention relates to an electrical power source having a static converter and a welding transformer for a resistance welding machine, using a first static frequency converter constructed of semiconductor elements whose output alternating voltage has half waves formed by pulse trains and where welding has an almost square course known from German Publication No. 1,613,730.

Med en sådan energikilde frembringes der højfrekvente svejse-10 strømme, hvis impulsform tilnærmelsesvis danner et rektangel eller et kvadrat. Den kendte indretning arbejder dog kun i begrænset grad tilfredsstillende, fordi impulsformen kun kan påvirkes i et snævert interval. En regulering af den overførte svejseenergi er ikke påtænkt for denne kendte energikilde.With such an energy source, high-frequency welding currents are produced, the pulse shape of which forms approximately a rectangle or a square. However, the known device only works to a limited extent satisfactorily, because the pulse shape can only be affected at a narrow interval. A regulation of the transmitted welding energy is not envisaged for this known source of energy.

ISICE

Opfindelsen har til formål at tilvejebringe en elektrisk energikilde af den indledningsvis angivne art, hvor impulsformen kan gøres mere firkantet og både ampi i tuden og impuls/pauseforholdet for svejsestrømmen kan varieres inden for et bredt 20 område og følge de øjeblikkelige behov under svejseoperationen .The invention has for its object to provide an electrical energy source of the type initially specified, in which the impulse shape can be made more square and both the amp in the spout and the pulse / pause ratio of the welding current can be varied within a wide range and follow the immediate needs during the welding operation.

Dette opnås ifølge opfindelsen ved at der parallelt med den første frekvensomformer er koblet mindst en anden frekvensom-25 former, hvis afgangsvekselspænding kan adderes til afgangsvekselspændingen fra den første frekvensomformer i svejsetransformatorens primær kreds, og hvor impulserne fra afgangsveksels pændi ngerne først adderes for at opnå stejle begyndelsesflanker for svejsestrømmen, og hvor impulserne i halvbølgens 30 videre forløb leveres skiftevis fra frekvensomformerne.This is achieved according to the invention by coupling at least one other frequency converter parallel to the first frequency converter, whose output alternating voltage can be added to the output alternating voltage of the first frequency converter in the welding transformer primary circuit and where the pulses from the output alternating current are first applied. starting flanks for the welding current, and the pulses in the further course of the half-wave 30 are alternately supplied from the frequency converters.

En række fordelagtige udførelsesformer for enkelthederne ved denne energikilde er angivet i krav 2-8.A number of advantageous embodiments of the details of this energy source are set forth in claims 2-8.

35 Ved opbygning af den opfinderiske energikilde med mindst to ens frekvensomformere, hvis afgangsvekselspændinger kan adderes fasesynkront i primærkredsen af en svejsetransformer ved begyndelsen af en svejsestrømshalvbølge, kan der opnås impuls-By constructing the inventive energy source with at least two equal frequency converters, whose output alternating voltages can be added phase synchronously in the primary circuit of a welding transformer at the beginning of a welding current half-wave, the

DK 159011BDK 159011B

2 former med en stor frontstej1 hed. Herved muliggøres et nøjagtigt svejsestarttidspunkt og en nøjagtig indkobling af svejse-apparatet. Endvidere tilvejebringer den store f1 ankestej1 hed af svejsestrømstigningen i sekundærkredsen af svejsetransfor-5 meren en svejsning med en meget lav frekvens også ved store fremstillingshastigheder. Svejsestrømmen kan reverseres i et negligerbart kort tidsrum, så at frekvensen næsten ingen indflydelse har på svejsesømmens kvalitet. Ved at vælge en lav frekvens af svejsestrømmen (linder fs = 100 Hz) kan man i ud-10 strakt grad undgå tab ved induktive hvirveIstrømme. Den i krav 7 og 8 angivne strømreguler i ng muliggør en nøjagtig dosering af svejseenergien.2 shapes with a large front floor1. This allows an accurate welding start time and an accurate wiring of the welding apparatus. Furthermore, the large frequency of welding current increase in the secondary circuit of the welding transformer provides welding with a very low frequency even at high manufacturing speeds. The welding current can be reversed for a negligible short period of time, so that the frequency has almost no effect on the quality of the weld seam. By choosing a low frequency of the welding current (linder fs = 100 Hz), losses to inductive vortex currents can be greatly avoided. The current control in ng of claims 7 and 8 allows an accurate dosage of the welding energy.

Da frekvensformerne er opbygget ens, kan der på simpel måde 15 parallelforbindes lige så mange frekvensomformere, som er nødvendige for at opnå en hurtig voksende strøm eller en hurtig reversering af strømmen.Since the frequency forms are constructed in the same way, just as many frequency converters can be paralleled as are necessary to obtain a fast growing current or a rapid reversal of the current.

Opfindelsen forklares nærmere nedenfor i forbindelse med teg-20 ningen, hvor fig. 1 er et strømskema for den elektriske energikilde ifølge opfindelsen, og 25 fig. 2 er et arbejdsdiagram for energikilden ifølge opfindelsen .The invention is further explained below in connection with the drawing, in which fig. 1 is a schematic diagram of the electrical energy source according to the invention, and FIG. 2 is a working diagram of the energy source according to the invention.

Fig. 1 viser en elektrisk energikilde ifølge opfindelsen, der i det væsentlige er opbygget af en første frekvensomformer 10 30 ogen anden frekvensomformer 11. Udgangene fra de to frekvensomformere 10 og 11 er tilsluttet til primærkredsen af en svej-setransf ormer 12, medens deres indgange påtrykkes en netspænding på eksempelvis 3 x 380 V vekselstrøm. Netspændingen når over skilletransformere 13 og 14 til konventionelle ensretter-35 broer 15 og 16, som frembringer en jævnspænding, hvormed de egentlige vekselrettertrin, der hver især består af et transistorstyretrin (kommutering) 17 eller 18 og et tyristoreffekt-trin 19 eller 20, strømfødes. Opbygningen og funktionen af de 3FIG. 1 shows an electrical power source according to the invention, which is essentially built up by a first frequency converter 10 and a second frequency converter 11. The outputs of the two frequency converters 10 and 11 are connected to the primary circuit by a welding transformer 12 while their inputs are applied to a mains voltage of, for example, 3 x 380 V AC. The mains voltage reaches across separating transformers 13 and 14 to conventional rectifier bridges 15 and 16, generating a DC voltage by which the actual inverter stages, each consisting of a transistor control step (commutation) 17 or 18 and a thyristor power stage 19 or 20, are fed. . The structure and function of the 3

DK 159011BDK 159011B

to sidstnævnte trin fremgår af beskrivelsen til tysk offentliggørelsesskrift nr. 2.336.429.the latter two steps appear in the description of German Publication No. 2,336,429.

Energikilden ifølge opfindelsen omfatter desuden en svejse-5 strømregulator 21 og en frekvensregulator 22, som er bestanddele af en ikke nærmere beskrevet styringselektronik. Svejse-strømregulatoren 21 er forbundet med en tilbagekoblingsledning, som gør det muligt at registrere eller måle en ER-værdi for strømmen enten i sekundærkredsen eller i primærkredsen med 10 en måleværdiomformer 23 henholdsvis 24. Frekvensregulatoren 22 bestemmer efter forudstilling frekvensen af den svejsestrøm, der strømmer gennem elektroderuller 25 og det mellemliggende, ikke viste svejseemne.The energy source according to the invention further comprises a welding current regulator 21 and a frequency regulator 22 which are components of a control electronics not further described. The welding current controller 21 is connected to a feedback line, which allows an ER value for the current to be detected or measured either in the secondary circuit or in the primary circuit with a measurement value converter 23 and 24. The frequency controller 22, after presetting, determines the frequency of the welding current flowing. through electrode rollers 25 and the intermediate weld not shown.

15 Ved hjælp af fig. 2 skal den principielle funktion af en energikilde ifølge opfindelsen forklares nærmere.15 By means of FIG. 2, the principle function of an energy source according to the invention will be explained in more detail.

Diagrammet på fig. 2a viser den over primærkredsen af svejse-transf ormeren 12 herskende spænding Ui, og fig. 2b viser den 2o tilhørende svejsestrøm 1*2 i sekundærkredsen af svejsetransformeren 12. Med en af frekvensomformerne 10, 11 kan der frembringes en spændingsimpuls med en bestemt længde og amplitude.The diagram of FIG. 2a shows the voltage U1 prevailing over the primary circuit of the welding transformer 12; and FIG. 2b shows the associated welding current 1 * 2 in the secondary circuit of the welding transformer 12. With one of the frequency converters 10, 11 a voltage pulse of a certain length and amplitude can be generated.

Ved begyndelsen af en halvbølge af svejsestrømmen indtræffer den fasesynkrone addition af to sådanne spændingsimpulser.At the beginning of a half-wave of the welding current, the phase synchronous addition of two such voltage pulses occurs.

25 Svejsestrømmen i2 i sekundærkredsen stiger stejlt. På meget kort tid når svejsestrømmen op på sin indstillede amplitude, der holdes konstant af svejsestrømregulatoren 21. For at holde svejsestrømmen på en konstant værdi i løbet af en halvbølge frembringes der af frekvensomformerne 10 og 11 vekselvise 30 spændingsimpulser, der i sekundærkredsen fremkalder en amplitudemæssig lille modulation af svejsestrømmen i2 med en forholdsvis høj frekvens. Efter udløbet af den første halvbølge af den firkantbølgeformede svejsestrøm i2 genindkobles begge frekvensomformerne 10 og 11 fasesynkront og additivt til pri-35 mærkredsen af svejsetransformeren 12 (se fig. 2a), så at der sker en reversering af svejsestrømmen i2 efter et negligerbart kort tidsrum.25 The welding current i2 in the secondary circuit increases steeply. In a very short time, the welding current reaches its set amplitude which is held constant by the welding current regulator 21. In order to keep the welding current at a constant value during a half-wave, frequency pulses 10 and 11 generate alternating small voltage pulses in the secondary circuit. modulation of the welding current i2 at a relatively high frequency. After the first half-wave of the square-wave-shaped welding current i2, both frequency converters 10 and 11 are phase-synchronously and additive reconnected to the primary circuit of the welding transformer 12 (see Fig. 2a), so that a reversal of the welding current i2 occurs after a negligible time.

Claims (8)

1. Energikilde med en statisk omformer og en svejsetransformer (12) til en modstandssvejsemaskine, hvor der anvendes en første statisk frekvensomformer (10), der er opbygget af halv-lederelementer, og hvis afgangsvekselspænding har halvbølger, 20 der er dannet af impulstog, og hvor svejsestrømshalvbølgerne har et næsten firkantet forløb, kendetegnet ved, at der parallelt med den første frekvensomformer (10) er koblet mindst en anden frekvensomformer (11), hvis afgangsvekselspænding kan adderes til afgangsvekselspændingen fra den første 25 frekvensomformer (10) i svejsetransformatorens (12) primær kreds, og hvor impulserne fra afgangsvekselspændingerne først adderes for at opnå stejle begyndelsesflanker far svejs-estrøm-men, og hvor impulserne i halvbølgens videre forløb leveres skiftevis fra frekvensomformerne. 30An energy source with a static converter and a welding transformer (12) for a resistance welding machine, using a first static frequency converter (10), which is constructed of semiconductor elements and whose output alternating voltage has half waves, formed by pulse trains, and wherein the welding current semiconductors have a nearly square gradient, characterized in that at least one other frequency converter (11) is coupled parallel to the first frequency converter (11) whose output alternating voltage can be added to the output alternating voltage of the first frequency converter (10) 12 primary circuit, and where the pulses from the output alternating voltages are first added to obtain steep initial flanks for the welding current and where the pulses in the further course of the half-wave are supplied alternately from the frequency converters. 30 2. Energikilden ifølge- krav 1, kendete g* net ved, åt amplituderne af afgangsvekselspændingerne fra frekvensomformere (10, 11) kan varieres. 352. The energy source according to claim 1, characterized in that the amplitudes of the output alternating voltages from frequency inverters (10, 11) can be varied. 35 3- Energikilde ifølge krav 1, kendetegnet ved, at amplituden af afgangsvekselspændingen af den første frekvens-omformer (10) kan varieres, og at amplituden af afgangsvekselspændingen af den anden frekvensomformer (11) er konstant. DK 159011 EPower source according to claim 1, characterized in that the amplitude of the output alternating voltage of the first frequency converter (10) can be varied and that the amplitude of the output alternating voltage of the second frequency converter (11) is constant. DK 159011 E 4. Energikilde ifølge krav 1, kendetegnet ved, at amplituderne af afgangsvekselsændingerne fra frekvensomformer-ne (10, 11) er konstante.Energy source according to claim 1, characterized in that the amplitudes of the output alternation changes from the frequency converters (10, 11) are constant. 5. Energikilde ifølge krav 1-4, kendetegnet ved, at impuls/pause-forholdene for afgangsvekselspændingerne af frekvensomformerne (10, 11) kan varieres.Energy source according to claims 1-4, characterized in that the pulse / pause conditions for the output alternating voltages of the frequency inverters (10, 11) can be varied. 6. Energikilde ifølge krav 1-5, kendetegnet ved, at 10 impulserne af afgangsvekselspændingerne af frekvensomformerne (10, 1.1) er f irkantbølgeformede .Energy source according to claims 1-5, characterized in that the 10 pulses of the output alternating voltages of the frequency inverters (10, 1.1) are square wave. 7. Energikilde ifølge krav 1-6, kendetegnet ved, at sekundærkredsen af svejsetransformeren (12) er forbundet 15 med en måleværdiomformer (23), hvis udgangssignal er propor tionalt med ER-værdien af svejsestrømmen (12) og tilføres en svejsestrømregulator (21), og at den udgang fra svejsestrøm-regulatoren (21), der fører indstillingssignalet, er forbundet med frekvensomformerne (10, 11). 20Energy source according to claims 1-6, characterized in that the secondary circuit of the welding transformer (12) is connected to a measuring value converter (23), the output of which is proportional to the ER value of the welding current (12) and to a welding current controller (21). and that the output of the welding current regulator (21) conducting the setting signal is connected to the frequency inverters (10, 11). 20 8. Energikilde ifølge krav 1-6, kendetegnet ved, at primærkredsen af svejsetransformeren (12) er forbundet med en måleværdiomformer (24), hvis udgangssignal er proportionalt med ER-værdien af svejsestrømmen (12) og tilføres en svejse- 25 strømregulator (21), og at den udgang fra svejsestrømregu1 atoren (21), der fører indsti 11 ingssignalet, er forbundet med frekvensomformerne (10, H). 30 35Power source according to claims 1-6, characterized in that the primary circuit of the welding transformer (12) is connected to a measuring value converter (24), the output of which is proportional to the ER value of the welding current (12) and to a welding current controller (21). ) and that the output of the welding current controller (21) conducting the tuning signal is connected to the frequency inverters (10, H). 30 35
DK010483A 1981-05-13 1983-01-12 ELECTRICAL ENERGY SOURCE FOR A RESISTANCE WELDING MACHINE DK159011C (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP81103674 1981-05-13
EP81103674A EP0064570B2 (en) 1981-05-13 1981-05-13 Electric energy source for a resistance welding machine
PCT/DE1982/000097 WO1982004000A1 (en) 1981-05-13 1982-05-08 Electric energy source for a resistance-welder
DE8200097 1982-05-08

Publications (4)

Publication Number Publication Date
DK10483A DK10483A (en) 1983-01-12
DK10483D0 DK10483D0 (en) 1983-01-12
DK159011B true DK159011B (en) 1990-08-20
DK159011C DK159011C (en) 1991-02-11

Family

ID=8187710

Family Applications (1)

Application Number Title Priority Date Filing Date
DK010483A DK159011C (en) 1981-05-13 1983-01-12 ELECTRICAL ENERGY SOURCE FOR A RESISTANCE WELDING MACHINE

Country Status (9)

Country Link
EP (1) EP0064570B2 (en)
JP (1) JPS58500702A (en)
AT (1) ATE15617T1 (en)
BR (1) BR8207698A (en)
CA (1) CA1183578A (en)
DE (1) DE3172302D1 (en)
DK (1) DK159011C (en)
ES (1) ES511904A0 (en)
WO (1) WO1982004000A1 (en)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0185014B1 (en) * 1984-06-15 1989-05-31 Square D Company Resistance welder
IT1179889B (en) * 1984-12-21 1987-09-16 Comau Spa RESISTANCE ELECTRIC WELDING EQUIPMENT
US5196668A (en) * 1988-11-17 1993-03-23 Honda Giken Kogyo Kabushiki Kaisha DC resistance welding apparatus
US5229567A (en) * 1988-11-17 1993-07-20 Honda Giken Kogyo Kabushiki Kaisha Switching control system for controlling an inverter of a spot resistance welding apparatus
GB2225909B (en) * 1988-11-17 1993-11-24 Honda Motor Co Ltd DC resistance welding apparatus
JPH03189079A (en) * 1989-12-18 1991-08-19 Honda Motor Co Ltd Dc resistance welding equipment
JPH0780058B2 (en) * 1989-12-18 1995-08-30 本田技研工業株式会社 DC resistance welding equipment
JPH0780059B2 (en) * 1989-12-19 1995-08-30 本田技研工業株式会社 DC resistance welding equipment
IT1242893B (en) * 1990-12-27 1994-05-18 Cefin Spa ELECTRONIC DEVICE FOR THE MANAGEMENT AND CONTROL OF THE ELECTRICAL POWER SUPPLY FOR RESISTANCE WELDING, IN PARTICULAR OF METAL BOX BODIES.
DE4331826C1 (en) * 1993-09-18 1994-12-08 Sibea Gmbh Ingenieurbetrieb Fu Method of resistance welding thin sheet and arrangement for carrying out the method
EP0646433A1 (en) * 1993-09-30 1995-04-05 Siemens Aktiengesellschaft Method, apparatus for high speed resistance welding of thin sheets
JPH081351A (en) * 1994-06-21 1996-01-09 Nasu Toa Kk Method and device for invertor control type ac resistance welding
JP4426693B2 (en) * 2000-03-22 2010-03-03 ミヤチテクノス株式会社 Metal member joining method and reflow soldering method
CN102227283B (en) * 2008-09-30 2013-11-13 高周波热炼株式会社 Welding device for metal construction and welding method for metal construction

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Publication number Priority date Publication date Assignee Title
DE2004609B2 (en) * 1970-02-02 1972-09-21 Standard Elektrik Lorenz Ag, 7000 Stuttgart DC VOLTAGE CONVERTER
DE2913627A1 (en) * 1979-04-05 1980-10-16 Messer Griesheim Gmbh DEVICE FOR DC AND / OR AC ARC WELDING WITH AN INVERTER

Also Published As

Publication number Publication date
WO1982004000A1 (en) 1982-11-25
DK159011C (en) 1991-02-11
BR8207698A (en) 1983-05-10
JPH0221917B2 (en) 1990-05-16
ES8303957A1 (en) 1983-02-16
JPS58500702A (en) 1983-05-06
EP0064570B2 (en) 1990-07-11
EP0064570B1 (en) 1985-09-18
CA1183578A (en) 1985-03-05
ES511904A0 (en) 1983-02-16
DE3172302D1 (en) 1985-10-24
ATE15617T1 (en) 1985-10-15
DK10483A (en) 1983-01-12
EP0064570A1 (en) 1982-11-17
DK10483D0 (en) 1983-01-12

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