Wire cut electrical-discharge machining apparatus
US5306888A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1993 |
| Grant date | Apr 26, 1994 |
| Priority date | — |
| Expiry date | Apr 15, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23H7/20
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An apparatus for preventing damage and malfunction to workpiece and electrode travelling system by quickly and reliably detecting wire electrode breakage during the wire cut discharge machining and, in the event of breakage, stopping machining or the like. Unlike conventional mechanical detecting means and devices for detecting the severing of a wire electrode from its supply reel, the present apparatus detects the position of the spark discharge pulse along the axial direction of the wire electrode to determine whether the location is inside or outside the thickness of the workpiece. If the spark position is outside the workpiece thickness and continues for a predetermined time period, the apparatus determines that a wire breakage exists. In addition, the apparatus attempts to discriminate a wire electrode breakage from other malfunctions, especially when the spark position is detected as occurring outside the workpiece thickness, and if a feed member wear situation is detected, the position of the sliding contact of the feed member can be updated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.