Method and apparatus for testing electrodes in an EDM process

• US 6,310,312 B1
• Filed: 12/23/1999
• Issued: 10/30/2001
• Est. Priority Date: 07/02/1999
• Status: Expired due to Fees

• Current Assignee: United Technologies Corporation (Rtx Corporation)
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Reed, Gordon, Grenfell, Wilfred, Davis, Thomas R., Higuerey, Evelitsa
• Primary Examiner(s): Copenheaver, Blaine
• Assistant Examiner(s): DUNN, COLLEEN P
• Application Number:
  US09/471,581
• Time in Patent Office: 677 Days
• Field of Search: 219/69.11, 219/69.15, 219/69.17
• US Class Current: 219/69.11
• CPC Class Codes: B23H 1/00 Electrical discharge machining, i.e. removing metal with a series of rapidly recurring electrical discharges between an electrode and a workpiece in the presence of a fluid dielectric
• CPC Class Codes: B23H 11/00 Auxiliary apparatus or details, not otherwise provided for
• CPC Class Codes: B23H 7/265 Mounting of one or more thin electrodes
• CPC Class Codes: B23H 9/10 Working turbine blades or nozzles
• CPC Class Codes: B23H 9/14 Making holes

Abstract

An automated method and apparatus for electrode discharge machining wherein method includes moving the tool holder to the electrode loader, automatically mounting an electrode into the tool holder and then testing the electrode for conformance to geometric and dimension tolerances and testing the electrode for proper alignment in the tool holder and thus proper alignment relative to the workpiece just prior to moving the tool holder to the workpiece area for machining. The apparatus includes a moveable servomechanism with a tool holder, an electrode magazine, and a sensor module for testing an electrode mounted in the tool holder. The sensor module has a recess configuration of conductive material complimentary to the electrode such that the electrode will make contact with the conductive material when inserted into the sensor module if the electrode is out of tolerance or misaligned in the tool holder.

Claims

1. An electrode discharge machining (EDM) machining method with an EDM apparatus of the type having a tool holder for mounting an electrode, an electrode loader with a supply of electrodes, a sensor module, and a workpiece mounting area for mounting the workpiece to be machined, the method comprising the steps of:

moving the tool holder to the electrode loader;

mounting an electrode having at least one tooth into the tool holder;

moving the tool holder away from the electrode loader;

inserting the electrode mounted in the tool holder into the sensor module to test the electrode for conformance to predetermined tolerances;

moving the tool holder to the workpiece area; and

machining the workpiece.

2. The method of claim 1 comprising testing the electrode mounted in the tool holder for proper alignment of the electrode in the tool holder.

3. The method of claim 1 wherein the step of testing the electrode for conformance to predetermined tolerances comprises simultaneously testing the electrode for proper alignment in the tool holder.

4. The method of claim 1 wherein the step of testing the electrode for conformance to predetermined tolerances comprises:

providing a sensor module having a recess configuration of conductive material complementary to the electrode such that contact of the electrode with the conductive material when the electrode is inserted into the recess configuration of the sensor modules indicates that the electrode is out-of-tolerance or misaligned in the tool holder;

inserting the electrode into the sensor module; and

determining if the electrode is in contact with the conductive material of the recess.

5. The method of claim 1 wherein the EDM apparatus is of the type having a sensor module for testing the electrode for conformance to predetermined tolerances, wherein the step of testing the electrode comprises:

positioning the electrode and sensor module in a testing position after the step of moving the tool holder away from the electrode loader; and

testing the electrode for conformance to tolerances.

6. The method of claim 5 wherein the step of positioning the electrode and sensor module in a testing position comprises moving the sensor module into a testing position relative to the electrode.

7. The method of claim 5 wherein the step of positioning the electrode and sensor module in a testing position comprises moving the electrode into a testing position relative to the sensor module.

8. The method of claim 1 wherein the EDM apparatus is of the type having a sensor module with a recess configuration of conductive material complementary to the electrode such that contact of the electrode with the conductive material when the electrode is inserted into the sensor module recess configuration indicates that the electrode is out-of-tolerance or misaligned in the tool holder, wherein the step of testing the electrode comprises:

positioning relatively the electrode and sensor module such that the electrode is disposed in the recess configuration of the sensor module; and

determining whether the electrode is in contact with the conductive material.

9. The method of claim 8 wherein the step of positioning the electrode and sensor module comprises moving the sensor module to the electrode so that the electrode is disposed in the recess configuration of the sensor module.

10. The method of claim 8 wherein the step of positioning the electrode and sensor module comprises moving the electrode to the sensor module so that the electrode is disposed in the recess configuration of the sensor module.

11. An electrode discharge machine apparatus comprising:

a servomechanism having a tool holder for mounting an electrode;

an electrode loader for mounting an electrode in the tool holder;

a workpiece area for supporting a workpiece to be machined;

said servomechanism being movable from said electrode loader to said workpiece area; and

a sensor for receiving therein an electrode mounted in the tool holder to test the electrode for conformance to predetermined tolerances.

12. The device of claim 11 wherein the sensor comprises

a sensor module with a recess configuration of conductive material complementary to an electrode such that contact of the electrode with the conductive material when the electrode is inserted into the sensor module recess configuration indicates that the electrode is out-of-tolerance or misaligned in the tool holder.

13. The device of claim 12 wherein the recess configuration of the sensor comprises a plurality of recesses complementary to a plurality of teeth on said electrode.

14. An electrode discharge machining (EDM) machining method with an EDM apparatus of the type having a tool holder for mounting an electrode, an electrode loader with a supply of electrodes, and a workpiece mounting area for mounting the workpiece to be machined, the method comprising the steps of:

moving the tool holder to the electrode loader;

mounting an electrode having at least one tooth into the tool holder;

moving the tool holder away from the electrode loader;

providing a sensor module having a recess configuration of conductive material complementary to the electrode such that contact of the electrode with the conductive material when the electrode is inserted into the recess configuration of the sensor modules indicates that the electrode is out-of-tolerance or misaligned in the tool holder;

inserting the electrode into the sensor module;

determining if the electrode is in contact with the conductive material of the recess;

moving the tool holder to the workpiece area; and

machining the workpiece.

15. An electrode discharge machining (EDM) machining method with an EDM apparatus of the type having a tool holder for mounting an electrode, an electrode loader with a supply of electrodes, a sensor module with a recess configuration of conductive material complementary to the electrode such that contact of the electrode with the conductive material when the electrode is inserted into the sensor module recess configuration indicates that the electrode is out-of-tolerance or misaligned in the tool holder, and a workpiece mounting area for mounting the workpiece to be machined, the method comprising the steps of:

moving the tool holder to the electrode loader;

mounting an electrode having at least one tooth into the tool holder;

moving the tool holder away from the electrode loader;

positioning relatively the electrode and sensor module such that the electrode is disposed in the recess configuration of the sensor module;

determining whether the electrode is in contact with the conductive material;

moving the tool holder to the workpiece area; and

machining the workpiece.

16. The method of claim 15 wherein the step of positioning the electrode and sensor module comprises moving the sensor module to the electrode so that the electrode is disposed in the recess configuration of the sensor module.

17. The method of claim 15 wherein the step of positioning the electrode and sensor module comprises moving the electrode to the sensor module so that the electrode is disposed in the recess configuration of the sensor module.

18. An electrode discharge machine apparatus comprising:

a servomechanism having a tool holder for mounting an electrode;

an electrode loader for mounting, an electrode in the tool holder;

a workpiece area for supporting a workpiece to be machined;

said servomechanism being movable from said electrode loader to said workpiece area; and

a sensor for testing an electrode mounted in the tool holder for conformance to predetermined tolerances, said sensor including a sensor module with a recess configuration of conductive material complementary to an electrode such that contact of the electrode with the conductive material when the electrode is inserted into the sensor module recess configuration indicates that the electrode is out-of-tolerance or misaligned in the tool holder.

19. The device of claim 18 wherein the recess configuration of the sensor comprises a plurality of recesses complementary to a plurality of teeth on said electrode.