Consumable electrode DC arc welder
US5942139A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 1998 |
| Grant date | Aug 24, 1999 |
| Priority date | — |
| Expiry date | Jan 20, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K9/0956
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
DC power from a smoothing capacitor is converted into high frequency power by an inverter, and then lowered by an output transformer. The lowered high frequency power is converted into DC power by an output rectifier and a DC reactor, and then supplied to a load. The load is short-circuited and then opened to initiate arcing. The short-circuiting and the arcing alternate. An auxiliary rectifier provides a load-voltage representative signal, and a current detector detects a load current. A load-current representative signal is differentiated by a differentiation circuit. The signals from the auxiliary rectifier, the current detector and the differentiation circuit, and a reference signal are applied to an operational amplifier. A control circuit controls the inverter such that the output of the operational amplifier can be zero. An integration circuit receives at least the load-voltage representative signal to detect a period of a cycle consisting of the arcing and the short-circuiting and provide an operation-cycle-period representative signal to the operational amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.