Arc welder with timed control of arcing recovery and means for reducing weight, size, and power loss in the welder
US5343017A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1993 |
| Grant date | Aug 30, 1994 |
| Priority date | — |
| Expiry date | Sep 13, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/10
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An arc welder provided with a low frequency square waveform a.c. power supply as a main power supply for welding in order to improve its power of recovering an arc which may go out at the time of polarity transition of a welding load and an auxiliary d.c. power supply for super-posing its output upon the input of the main power supply to further improve the recovering power, in which a switching element is inserted in a supply path of the output of the auxiliary d.c. power supply and the switching element is put in conduction by a suitable control device only for a necessary shortest arc recovery time in order to reduce a power loss due to continuous supply of the auxiliary d.c. output. The welder may include a diode which is put in conduction in response to an excessive transient voltage induced at the input of an invertor of the main power supply at the time of polarity transition of the welding load and, in order to prevent excessive charge of the capacitor in this case, the conduction time of the switching element may be extended to discharge an excess charge through the switching element to the invertor when a voltage across the capacitor exceeds a predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.