Adaptive method and apparatus for controlling machining current in electric discharge machines
US5352859A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1993 |
| Grant date | Oct 4, 1994 |
| Priority date | — |
| Expiry date | Apr 29, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23H7/20
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An adaptive apparatus for controlling the discharge current comprises a circuit for sensing the gap voltage and a circuit for sensing the gap current. Based upon these sensed conditions at the gap, the waveform of the discharge current is detected. The waveform of the current is compared to several reference levels at certain times during the waveform in order to determine the condition at the gap. The reference levels may be varied in accordance with the machining method, such as in accordance with the peak value of current. The off times for the pulses are then varied according to the conditions at the gap. The pulses of discharge current are therefore controlled in order to provide the optimal machining rate and an improved workpiece surface finish while reducing arc discharges.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.