Patent US4331524A successfully refreshed from Google Patents.
US4331524A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and apparatus for electrolytic metal processing
Assignee: SMS Elotherm GmbH
•
Filing: 1980-05-13
•
Granted: 1982-05-25
•
Expires: 2000-05-13
Abstract
Abstract A method and apparatus for electrolytic processing of a metallic workpiece in which short circuits in the operating gap which produce an arc are detected and extinguished by an auxiliary d.c. current of limited duration and counter to the direction of flow of the operating current without withdrawing the electrode or cutting off the operating current.
Inventors
- 👤 Hans Matthes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:06
CPC Classifications
B; B23; B23H; B23H3/00; B23H3/02
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
122 words
A process for electrolytic processing of a metallic workpiece comprising the steps of: applying a direct current voltage to an operating gap between the workpiece and a processing electrode to produce an operating direct current, advancing said electrode by a driving motor against the surface of said workpiece to remove material, supplying electrolyte to said gap, detecting a short circuit producing an arc in said gap, and extinguishing said arc without reversing said motor by causing, upon detecting of said short circuit, an auxiliary d.c. current of temporally limited duration to flow in said gap, the auxiliary current being in a direction counter to the direction of flow of said operating direct current to thereby cancel and extinguish any short circuit current.
Claim 2
Dependent Claim
122 words
A process for electrolytic processing of a metallic workpiece comprising the steps of: applying a direct current voltage to an operating gap between the workpiece and a processing electrode to produce an operating direct current, advancing said electrode by a driving motor against the surface of said workpiece to remove material, supplying electrolyte to said gap, detecting a short circuit producing an arc in said gap, and extinguishing said arc without reversing said motor by causing, upon detecting of said short circuit, an auxiliary d.c. current of temporally limited duration to flow in said gap, the auxiliary current being in a direction counter to the direction of flow of said operating direct current to thereby cancel and extinguish any short circuit current.
Claim 3
Dependent Claim
66 words
A process as in claim 1 including the further steps of: detecting a short circuit in said gap which does not produce an arc, interrupting the operating direct current upon detecting a short circuit in said gap which does not produce an arc, and reversing the direction of movement of said electrode upon detecting a short circuit in said gap which does not produce an arc.
Claim 4
Dependent Claim
36 words
A process as in claim 2 including the further step of closing a short circuit switch connected in parallel with said gap upon detecting a short circuit in said gap which does not produce an arc.
Claim 5
Dependent Claim
51 words
A process as in claim 2 including the further step of supplying to said gap upon detecting a short circuit in said gap which does not produce an arc by supplying an auxiliary d.c. current of temporally limited duration and counter to the direction of flow of said operating direct current.
Claim 6
Dependent Claim
25 words
A process as in claim 1 or 2 wherein said step of detecting a short circuit which produces an arc includes detecting high frequency oscillations.
Claim 7
Dependent Claim
42 words
A process as in claim 1 or 2 wherein said step of extinguishing includes the steps of: charging a plurality of parallel connected capacitors to a voltage related to the voltage of said gap, and discharging at least one of said capacitors.
Claim 8
Independent Claim
117 words
An apparatus for ending a short circuit in an operating gap of an electrolytic processing machine in which an electrode is advanced toward the surface of a workpiece while a d.c. current voltage is applied to the gap to produce a d.c. operating current and remove material from said surface comprising: means for detecting a short circuit producing an arc in said gap, and means connected to said detecting means for causing, upon detection of said short circuit, an auxiliary d.c. current of temporally limited duration to flow in said gap, the auxiliary current being in a direction counter to the direction of flow of said operating current to thereby cancel and extinguish any short circuit current.
Claim 9
Independent Claim
117 words
An apparatus for ending a short circuit in an operating gap of an electrolytic processing machine in which an electrode is advanced toward the surface of a workpiece while a d.c. current voltage is applied to the gap to produce a d.c. operating current and remove material from said surface comprising: means for detecting a short circuit producing an arc in said gap, and means connected to said detecting means for causing, upon detection of said short circuit, an auxiliary d.c. current of temporally limited duration to flow in said gap, the auxiliary current being in a direction counter to the direction of flow of said operating current to thereby cancel and extinguish any short circuit current.
Claim 10
Independent Claim
117 words
An apparatus for electrolytic processing of a metallic workpiece comprising: an electrode, means for moving said workpiece in an operating gap toward and away from a surface of said workpiece, means for applying a d.c. voltage to said gap to produce a d.c. operating current and remove material from said surface, means for detecting a short circuit producing an arc in said gap, and means connected to said detecting means for causing, upon detection of said short circuit, an auxiliary d.c. current of temporally limited duration to flow in said gap, the auxiliary current being in a direction counter to the direction of flow of said operating current to thereby cancel and extinguish any short circuit current.
Claim 11
Independent Claim
117 words
An apparatus for electrolytic processing of a metallic workpiece comprising: an electrode, means for moving said workpiece in an operating gap toward and away from a surface of said workpiece, means for applying a d.c. voltage to said gap to produce a d.c. operating current and remove material from said surface, means for detecting a short circuit producing an arc in said gap, and means connected to said detecting means for causing, upon detection of said short circuit, an auxiliary d.c. current of temporally limited duration to flow in said gap, the auxiliary current being in a direction counter to the direction of flow of said operating current to thereby cancel and extinguish any short circuit current.
Claim 12
Dependent Claim
19 words
An apparatus as in claim 7 or 8 wherein said detecting means includes means for detecting high frequency oscillations.
Claim 13
Dependent Claim
69 words
An apparatus as in claim 7 or 8 further including further means for detecting a short circuit in said gap which does not produce an arc, means for interrupting the operating direct current in said gap upon detecting a short circuit which does not produce an arc, and means for reversing the direction of movement of said electrode upon detecting a short circuit which does not produce an arc.
Claim 14
Dependent Claim
38 words
An apparatus as in claim 10 further including a short circuit switch means connected in parallel with said gap and to said further means for closing when a short circuit is detected which does not produce an arc.
Claim 15
Dependent Claim
18 words
An apparatus as in claim 7 or 8 further including means for supplying liquid electrolyte to said gap.
Claim 16
Dependent Claim
37 words
An apparatus as in claim 7 or 8 wherein said detecting means includes a plurality of parallel connected capacitors, and means for charging said capacitors said supplying means includes for discharging at least one of said capacitors.
Claim 17
Dependent Claim
26 words
An apparatus as in claim 13 wherein said charging means includes means for detecting the voltage across said gap and charging said capacitors in accordance therewith.
Claim 18
Dependent Claim
67 words
An apparatus as in claim 14 further including further means for detecting a short circuit in said gap which does not produce an arc, means for interrupting the operating direct current in said gap upon detecting a short circuit which does not produce an arc, and means for reversing the direction of movement of said electrode upon detecting a short circuit which does not produce an arc.
Claim 19
Dependent Claim
21 words
An apparatus as in claim 15 further including logic means connected to each of said detecting means for discharging said capacitors.
References Cited (Backward Citations)
SU339381A1
Cited
SU250636A1
Cited
SU347144A1
Cited
US3617680A
Cited
US3673371A
Cited
US3749877A
Cited
US3825713A
Cited
US3884790A
Cited
US4242555A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-24 | 1985-11-23 | 1986-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-24 | 1989-11-23 | 1990-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-24 | 1993-11-23 | 1994-05-25 | $7700.00 | Window Closed / Lapsed |