Electrical machining device and method, hybrid machining system and method

Patent metadata

Field	Value
Publication number	US-11014178-B2
Application number	US-201715658855-A
Country	US
Kind code	B2
Filing date	Jul 25, 2017
Priority date	Sep 5, 2016
Publication date	May 25, 2021
Grant date	May 25, 2021

Abstract

An electrical machining method comprises machining a workpiece by an electrical machining device comprising an electrode; increasing a feedrate of the electrode at a first acceleration if a discharge current passing through the electrode and the workpiece is lower than a discharge current reference; and decreasing the feedrate of the electrode at a second acceleration if the discharge current is higher than the discharge current reference, wherein the second acceleration has an absolute value higher than that of the first acceleration.

First claim

The invention claimed is:

1. An electrical machining method comprising:
machining a workpiece by an electrical machining device comprising an electrode;
operating the electrical machine such that a discharge current is lower than a discharge current reference;
operating the electrical machine such that the discharge current is higher than the discharge current reference;
increasing a feedrate of the electrode towards the workpiece at a first acceleration when the discharge current passing through the electrode and the workpiece is lower than the discharge current reference; and
decreasing the feedrate of the electrode towards the workpiece at a second acceleration when the discharge current is higher than the discharge current reference, wherein the second acceleration has an absolute value higher than that of the first acceleration.

2. The method according to claim 1 , further comprising energizing the workpiece and the electrode by a constant voltage source.

3. The method according to claim 1 , further comprising:
detecting the discharge current passing through the electrode and the workpiece; and
comparing the discharge current with the discharge current reference.

4. The method according to claim 1 , wherein increasing the feedrate of the electrode comprises multiplying the feedrate by a first override ratio higher than an override ratio reference and decreasing the feedrate of the electrode comprises multiplying the feedrate by a second override ratio lower than the override ratio reference.

5. The method according to claim 4 , wherein the first override ratio is calculated by

R
1

=

R
max

-

R
ref

I
min

-

I
ref

⁢

(

I
r

-

I
min

)

+

R
max

,

the second override ratio is calculated by

R
2

=

R
min

-

R
ref

I
max

-

I
ref

⁢

(

I
r

-

I
max

)

+

R

min
,

wherein R 1 represents the first override ratio, R 2 represents the second override ratio, I r represents a real time discharge current, ref represents the discharge current reference, I min represents a minimum of the discharge current, I max represents a maximum of the discharge current, R ref represents the override ratio reference, R min represents a minimum of the override ratio, R max , represents a maximum of the override ratio, and



R
max

-

R
ref

I
min

-

I
ref



<



R
min

-

R
ref

I
max

-

I
ref



.

6. The method according to claim 1 . further comprising:
calculating a first override ratio by

R
1

=

R
max

-

R
ref

I
min

-

I
ref

⁢

(

I
r

-

I
min

)

Assignees

• Gen Electric

Inventors

• Liu Dong
• Trimmer Andrew Lee
• Luo Yuanfeng
• Hayashi Steven Robert

Classifications

• B23H1/024 Primary

  Detection of, and response to, abnormal gap conditions, e.g. short circuits (preventing short circuits or other abnormal discharges by altering machining parameters using adaptive control B23H7/16) · CPC title

• B23H7/30

  Moving electrode in the feed direction (B23H7/32 takes precedence) · CPC title

• B23H5/04

  Electrical discharge machining combined with mechanical working · CPC title

• B23H1/04 Primary

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

• B65H35/00

  Delivering articles from cutting or line-perforating machines; Article or web delivery apparatus incorporating cutting or line-perforating devices, e.g. adhesive tape dispensers (cutting or perforating machines or devices in general B26D, B26F) · CPC title