Method and apparatus for sink-type electrical discharge machining with control of pyrographite buildup
US5369239A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 18, 1992 |
| Grant date | Nov 29, 1994 |
| Priority date | — |
| Expiry date | May 18, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23H1/02
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A touch-type sensor is employed to detect the precise location of a corner of a machining electrode that may be susceptible to pyrographite buildup prior to actual machining of a workpiece. By detecting the precise location in this manner, a base or origin value can be maintained for subsequent comparison when the electrode is periodically checked for icicle formation or electrode erosion. When a deviation from the base or origin value is determined, one or more of a plurality of machining parameters, such as machining on time, wear ratio, fluid flow rate, or jumping height is modified in accordance with the amount of deviation detected. In order to further optimize the machining rate of the workpiece, the surface area of the electrode is periodically determined. The aforementioned machining parameters are varied accordingly, so that the optimum average current across the inter-electrode gap, as it relates to surface area, may be maintained. Furthermore the temperature at the surface of the machining electrode can be periodically determined. As the temperature at the surface approaches the critical temperature for pyrographite buildup and the like, the machining parameters can be m…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.