GB1434349A - Monitoring weld quality in electric resistance welding - Google Patents
Monitoring weld quality in electric resistance weldingInfo
- Publication number
- GB1434349A GB1434349A GB5379872A GB5379872A GB1434349A GB 1434349 A GB1434349 A GB 1434349A GB 5379872 A GB5379872 A GB 5379872A GB 5379872 A GB5379872 A GB 5379872A GB 1434349 A GB1434349 A GB 1434349A
- Authority
- GB
- United Kingdom
- Prior art keywords
- weld
- signal
- welding
- resistance
- fed
- 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
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
- B23K11/25—Monitoring devices
- B23K11/252—Monitoring devices using digital means
- B23K11/256—Monitoring devices using digital means the measured parameter being the inter-electrode electrical resistance
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
1434349 Welding by pressure RUBERY OWEN & CO Ltd and WELDING LIAISON Ltd 21 Feb 1974 [21 Nov 1972] 53798/72 Heading B3R In monitoring the quality of a weld made by electric resistance welding, the dynamic resistance of the weld (i.e. the quotient, instantaneous voltage drop across the welding electrodes / instantaneous welding current) is measured at predetermined successive instants during welding and the measured values are compared with corresponding values known to be characteristic of a good quality weld. An apparatus for spot welding comprises a pair of electrodes 1 which are fed a predetermined number of weld pulses at regular intervals during a welding period, each pulse being formed by a predetermined number of rectified cycles of three phrase mains supply. During each weld pulse a voltage signal produced by a variable gain amplifier 3, having input connections from the electrodes 1, is fed to a divider circuit 2. At the same time a welding current signal produced by a toroidal coil 4 about the lower electrode is fed to a variable gain amplifier 5 which is connected to a further amplifier 6 which produces a smoothed output signal and shifts the phase of the current signal so that it is in phase with the welding voltage signal and this smoothed phase shifted signal is also fed to the divider 2. The divider 2 divides the voltage signal by the current signal to produce a signal proportional to the resistance of the weld during the weld pulse, the weld pulse being sufficiently short for the resistance to remain substantially unchanged during that time. A succession of signals proportional to the instantaneous resistance of the weld are produced during a welding period and as each is produced it is compared with a corresponding one of a succession of reference values of resistance known to correspond to a good quality weld, these reference values being stored in a memory circuit 7 and fed successively to a comparator 10. Each signal proportional to the weld resistance is fed from the divider 2 to the comparator 10 via a low pass filter 8 and the comparator 10 compares each derived signal with each reference signal, a synchronizing pulse generator 9 in synchronism with the divider 2 ensuring that the second derived signal is compared with a second reference signal, &c. There are typically eight weld pulses and thus eight comparisons. An analogue switch circuit 11 driven by the generator 9 gates the reference signals. The comparator 10 feeds an error signal to a discriminator circuit 12 which produces a pass signal or a fail signal and these signals are fed to a device 13 which issues a warning so that an operator can take appropriate action or automatically rejects the failed weld. The rate of rise of resistance may also be measured. The apparatus may be used in the production of spot welded wheels for road vehicles, the rim being spot welded to the nave pressing at a number of points and wheels of doubtful quality can be automatically rejected by the application of a paint mark or by delivery to a reject shoot or both and an alarm can be signalled. The welding apparatus used may have multiple heads and successive sets of welds are made by rotating the wheels between welds. The resistance welding may be seam or flash-butt.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB5379872A GB1434349A (en) | 1972-11-21 | 1972-11-21 | Monitoring weld quality in electric resistance welding |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB5379872A GB1434349A (en) | 1972-11-21 | 1972-11-21 | Monitoring weld quality in electric resistance welding |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1434349A true GB1434349A (en) | 1976-05-05 |
Family
ID=10469017
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB5379872A Expired GB1434349A (en) | 1972-11-21 | 1972-11-21 | Monitoring weld quality in electric resistance welding |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB1434349A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2426529A1 (en) * | 1978-05-25 | 1979-12-21 | Carel Fouche Languepin | CONTROL AND CONTROL PROCEDURE OF A RESISTANCE WELDING OPERATION AND IMPLEMENTATION DEVICE |
FR2479723A1 (en) * | 1980-04-02 | 1981-10-09 | Weltronic Co | METHOD AND DEVICE FOR MONITORING AND CONTROLLING A RESISTANCE WELDING OPERATION |
FR2491798A1 (en) * | 1980-06-02 | 1982-04-16 | Nissan Motor | METHOD AND SYSTEM FOR DETERMINING THE QUALITY OF WELDING |
EP0685289A1 (en) * | 1994-05-31 | 1995-12-06 | Siemens Aktiengesellschaft | Welding current regulating device for spot-welding with a fuzzy-transducer for the quantitative detection of the strength of welding splatters |
-
1972
- 1972-11-21 GB GB5379872A patent/GB1434349A/en not_active Expired
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2426529A1 (en) * | 1978-05-25 | 1979-12-21 | Carel Fouche Languepin | CONTROL AND CONTROL PROCEDURE OF A RESISTANCE WELDING OPERATION AND IMPLEMENTATION DEVICE |
FR2479723A1 (en) * | 1980-04-02 | 1981-10-09 | Weltronic Co | METHOD AND DEVICE FOR MONITORING AND CONTROLLING A RESISTANCE WELDING OPERATION |
US4302653A (en) * | 1980-04-02 | 1981-11-24 | Weltronic Company | Method and apparatus for monitoring and controlling a resistance welding operation |
FR2491798A1 (en) * | 1980-06-02 | 1982-04-16 | Nissan Motor | METHOD AND SYSTEM FOR DETERMINING THE QUALITY OF WELDING |
US4521665A (en) * | 1980-06-02 | 1985-06-04 | Nissan Motor Co., Ltd. | Method and system for determining weld quality in resistance welding |
EP0685289A1 (en) * | 1994-05-31 | 1995-12-06 | Siemens Aktiengesellschaft | Welding current regulating device for spot-welding with a fuzzy-transducer for the quantitative detection of the strength of welding splatters |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4435631A (en) | Method and device for controlling the length of an electrical arc in an arc generating machine | |
US4521665A (en) | Method and system for determining weld quality in resistance welding | |
US3609285A (en) | Method and apparatus for monitoring weld quality | |
DE69818275D1 (en) | QUALITY MEASUREMENT OF WELDING | |
GB1527528A (en) | Methods of and apparatus for monitoring the quality of welds | |
GB1434349A (en) | Monitoring weld quality in electric resistance welding | |
US4562330A (en) | Spot weld quality monitoring system | |
US3588438A (en) | Electrical circuit | |
GB1254963A (en) | Improvements in the monitoring, and, if desired, controlling metal transfer in welding processes in electric welding | |
US5081338A (en) | Apparatus and method for monitoring weld quality | |
US4242561A (en) | Electric seam weld monitoring apparatus and method | |
US3673377A (en) | Apparatus and method for controlling or monitoring electric welding processes | |
US3345493A (en) | Monitor for detecting change in resistance between welded parts during welding current flow | |
US2740044A (en) | Resistance welding monitor control | |
US4577086A (en) | Monitoring in-service resistance of AC conductors | |
US4639569A (en) | Weld resistance measuring apparatus for a spot welder | |
US3774006A (en) | Resistance welding control | |
US3532853A (en) | Arc welding monitor system | |
US2440962A (en) | Circuit for measuring the last half cycle voltage across a resistance weld | |
US3518395A (en) | End weld control circuit | |
US3800119A (en) | Resistance welding monitor | |
US2577163A (en) | Resistance welding and resistance weld testing | |
GB1370869A (en) | Method and apparatus for producing a signal proportional to the electrical resistance across electrodes or workpiece holders | |
JPH0646632Y2 (en) | Continuous seam welding monitor | |
GB1301149A (en) | Improvements in the control of electrical spot welding |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
732 | Registration of transactions, instruments or events in the register (sect. 32/1977) | ||
PE20 | Patent expired after termination of 20 years |
Effective date: 19940220 |