DC power supply apparatus for arc-utilizing apparatuses
US6054674A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 14, 1999 |
| Grant date | Apr 25, 2000 |
| Priority date | — |
| Expiry date | Jan 14, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K9/1043
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An AC voltage applied among power input supply terminals is rectified by a rectifier, and the rectified voltage is adapted to be reduced in a voltage-reducing converter with a switch connected in parallel with it. A switching circuit connect smoothing capacitors in series or parallel to the voltage-reducing converter. Inverters are connected in parallel with the respective smoothing capacitors. The output voltages of the inverters are voltage-transformed by transformers. The transformed voltages from the transformers are converted to DC voltages by converters. A control unit renders the voltage-reducing converter operative and causes the switching circuit to connect the smoothing capacitors in series when a third AC voltage is applied among the power supply input terminals. When a second AC voltage lower than the third AC voltage is applied among the power supply input terminals, the control unit causes the switch connected in parallel with the voltage-reducing converter to be closed and causes the switching circuit to connect the smoothing capacitors in series. If a first AC voltage about one-half as high as the second AC voltage is applied, the control unit causes the switch to b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.