Patent · US Expired

Electric discharge machining apparatus

US6225589A · kind A · utility

47Cited by
14References
38Claims
0Family size

Inventor

Key dates

Filing dateMar 15, 1999
Grant dateMay 1, 2001
Priority date
Expiry dateMar 15, 2019

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23H7/265
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

In a three dimensional generic electric discharge machining (EDM) apparatus the positionable driver assembly (4) houses a discharge electrode (1) that is in the form of a continuous wire, exposing only a predetermined length, the working portion, of that wire for discharge machining. Additional portions of that wire are incrementally advanced (5) from the housing as needed. In one embodiment, that need arises from electrode erosion, and, as an incremental portion of the electrode's working portion is eroded away, an additional increment of wire is advanced from the housing to restore the working portion to the desired length. For automatic control of the working portion's length, a novel sensor (48, 49, 38, 39, 34) monitors the virtual location of the discharge spark that occurs off the tip of the electrode during machining; and a significant shift in position of the spark, indicative of electrode wear, is detected and acted upon by the apparatus (8) to automatically replenish the spent electrode portion. In another embodiment (FIG. 16), wire (75) is automatically advanced (5, FIG. 1) under control of a computer (8, FIG. 1) programmed to predict the progress of workpiece cutting in…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.