Patent · US Expired

Apparatus for regulating an electric discharge machining gap

US3973104A · kind A · utility

13Cited by
5References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 29, 1974
Grant dateAug 3, 1976
Priority date
Expiry dateJul 29, 1994

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23H7/18
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

The peak voltage of each discharge pulse is measured and, if the voltage of the pulse exceeds a high threshold value, there is also measured the time between the passing of that value and the moment the pulse voltage thereafter drops below a second lower threshold value. The two measurements are expressed in pulses that are combined, preferably by addition, to provide a regulating value, whose deviation ("error") from a standard value is predicted for a coming period, taking account of recent electrode position change as well as regulating value trend. The sign of the predicted error determines in which direction the electrode drive motor will be energized, but if the predicted error is less than a threshold value no motor energization occurs until the next error prediction. The sense in which the regulation operates is so defined that at a time when the electrodes are not already in relative movement an increase in the regulating value, at least if it persists, causes the electrodes to be moved closer together.

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