System and methods of multiple electrode electric discharge machining

Patent metadata

Field	Value
Publication number	US-10933480-B2
Application number	US-201715429943-A
Country	US
Kind code	B2
Filing date	Feb 10, 2017
Priority date	Feb 10, 2017
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

An electric discharge machining (EDM) system includes an electrode set having a plurality of electrodes. Each electrode is electrically-isolated from the other electrodes. The EDM system includes a power supply configured to generate an electric discharge between a workpiece and the electrode set to remove material from the workpiece. The power supply includes a multi-loop driver system and an AC-to-DC component that outputs DC electric power. The multi-loop driver system includes a plurality of power loop circuits coupled to an output of the AC-to-DC component. Each power loop circuit is electrically-isolated from other power loop circuits and is coupled to at least one electrode. The multi-loop driver system includes a drive controller coupled to the power loop circuits. The drive controller is configured to transmit at least one control signal to at least one power loop circuit to drive the AC-to-DC component to generate the electric discharge.

First claim

What is claimed is:

1. An electric discharge machining (EDM) system comprising:
an electrode set comprising a plurality of electrodes, each electrode of said plurality of electrodes electrically-isolated from other electrodes of said plurality of electrodes; and
a power supply configured to generate an electric discharge between a workpiece and said each electrode to remove material from the workpiece, said power supply comprising an AC-to-DC component configured to output DC electric power, said power supply further comprising a multi-loop driver system comprising:
a plurality of power loop circuits coupled to an output of said AC-to-DC component, each power loop circuit of said plurality of power loop circuits electrically-isolated from other power loop circuits of said plurality of power loop circuits, said each power loop circuit coupled to at least one electrode of said plurality of electrodes and said each power loop circuit comprising a transistor configured to switch between an ON state and an OFF state to generate a pulse of the DC electric power through said each power loop circuit; and
a drive controller coupled to said plurality of power loop circuits, said drive controller configured to transmit at least one control signal to at least one power loop circuit of said plurality of power loop circuits to drive said AC-to-DC component to generate the electric discharge.

2. The EDM system in accordance with claim 1 , wherein said electrode set further comprises a plurality of insulator components positioned between adjacent electrodes of said plurality of electrodes.

3. The EDM system in accordance with claim 1 , wherein said each electrode of said plurality of electrodes is fabricated from a substantially planar material.

4. The EDM system in accordance with claim 1 , wherein said transistor is a metal-oxide-silicon field-effect type transistor.

5. The EDM system in accordance with claim 1 , wherein said multi-loop driver system further comprises a plurality of current sensors, wherein said each power loop circuit comprises a respective current sensor of said plurality of current sensors operatively coupled to said transistor and operatively coupled to said drive controller for sensing an amount of current flowing through said transistor, and wherein said drive controller is configured to switch said transistor to the OFF state if an amount of current flowing through said transistor exceeds a predetermined threshold value.

6. The EDM system in accordance with claim 1 , wherein said multi-loop driver system further comprises a plurality of voltage sensors, wherein said each power loop circuit comprises a respective voltage sensor of said plurality of voltage sensors operatively coupled to said transistor and operatively coupled to said drive controller for sensing an amount of gap voltage between the workpiece and said at least one electrode.

7. The EDM system in accordance with claim 1 , wherein said multi-loop driver system further comprises a transistor-transistor logic to metal-oxide-silicon (TTL-to-MOS) driver configured to receive the at least one control signal and transmit at least one MOS signal having an increased current and increased voltage output level relative to the control signal, to said at least one power loop circuit.

8. The EDM system in accordance with claim 7 , wherein said at least one power loop circuit further comprises an optoisolator configured to electrically isolate said transistor from said drive controller.

9. The EDM system in accordance with claim 8 , wherein said at least one power loop circuit further comprises a driver component coupled between said optoisolator and said transistor, wherein said driver component is configured to transmit a current sufficient to change the state of said transistor.

10. An electric discharge machining (EDM) system comprising:
an electrode set comprising a plurality of electrodes, each electrode of said plurality of electrodes electrically-isolated from other electrodes of said plurality of electrodes;
a power supply comprising an AC-to-DC component configured to output DC electric power, and a plurality of power loop circuits coupled to an output of said AC-to-DC component, each power loop circuit of said plurality of power loop circuits electrically-isolated from other power loop circuits of said plurality of power loop circuits, wherein said each power loop circuit is coupled to at least one electrode of said plurality of electrodes and is configured to transmit pulsed DC electric power to said at least one electrode independent of another said each power loop circuit, and wherein said each power loop circuit comprises a transistor configured to switch between an ON state and an OFF state to generate a pulse of the DC electric power through said each power loop circuit;
a translation apparatus coupled to said electrode set and configured to adjust a position of said electrode set relative to a workpiece; and
a controller coupled to said translation apparatus and said power supply, said controller configured to control said translation apparatus to adjust a position of said electrode set relative to the workpiece based on an amount of gap voltage measured between said electrode set and the workpiece.

11. The EDM system in accordance with claim 10 , wherein said power supply further comprises a drive controller coupled to said plurality of power loop circuits, said drive controller configured to transmit at least one control signal to said each power loop circuit to drive said AC-to-DC component to generate an electric discharge between said electrode set and the workpiece.

12. The EDM system in accordance with claim 11 , wherein said drive controller transmits a first control signal to a first power loop circuit of said plurality of power loop circuits, and a second control signal to a second power loop circuit of said plurality of power loop circuits, wherein said first control signal and said second control signal are in phase and configured to generate simultaneous electric discharges between said first and second power loop circuits and the workpiece.

13. The EDM system in accordance with claim 11 , wherein said drive controller transmits a first control signal to a first power loop circuit of said plurality of power loop circuits, and a second control signal to a second power loop circuit of said plurality of power loop circuits, wherein said first control signal and said second control signal are out of phase and configured to generate sequential electric discharges between said first and second power loop circuits and the workpiece.

14. The EDM system in accordance with claim 11 , wherein said power supply further comprises a transistor-transistor logic to metal-oxide-silicon (TTL-to-MOS) driver configured to receive the at least one control signal and transmit at least one MOS signal having an increased current and increased voltage output level relative to the control signal, to said each power loop circuit.

15. The EDM system in accordance with claim 11 , wherein said each power loop circuit comprises:
an optoisolator configured to electrically isolate said transistor from said drive controller; and
a driver component coupled between said optoisolator and said transistor, wherein said driver component is configured to transmit a current sufficient to change the operating state of said transistor.

16. The EDM system in accordance with claim 10 , wherein said electrode set further comprising a plurality of insulator components positioned between adjacent electrodes of said plurality of electrodes.

Assignees

• Gen Electric

Inventors

• Luo Yuanfeng
• Adrian Richard Leigh
• Bridges Allan Richard
• Usmani Nouman

Classifications

• B23H1/028 Primary

  for multiple gap machining · CPC title

• B23H1/04

  Electrodes specially adapted therefor or their manufacture (B23H9/00 takes precedence) · CPC title

• B23H7/18

  for maintaining or controlling the desired spacing between electrode and workpiece · CPC title