US4041268A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for adjusting the eccentricity of a spark-erosion machining electrode endowed with a movement of circular translation and a device for the application of said method
Assignee: Agie Charmilles SA
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Filing: 1976-03-23
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Granted: 1977-08-09
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Expires: 1996-03-23
Abstract
Abstract After pre-forming of a cavity in a workpiece by means of an electrode of male form, movements of circular translation of increasing relative eccentricity are imparted to the electrode or the workpiece in order to complete machining of the cavity by the spark-erosion process while adjusting the eccentricity in successive steps. The orbital motion is stored in memory during at least one period of travel while the electrode-workpiece potential difference is compared with a reference voltage. A control signal delivered as a result of the comparison initiates the progression of eccentricity by one step when the potential difference has remained continuously higher than the reference voltage during the period of travel.
Inventors
- 👤 Pierre Braudeau
- 👤 Alfred Marie Aime Maillet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 01:08
CPC Classifications
B; B23; B23H; B23H7/00; B23H7/26; B23H7/28
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
68 words
A method for automatically increasing the eccentricity of a circular translation movement of an electrode relative to a workpiece, in a spark erosion machine, said movement having a period of travel, a machining voltage being applied between said electrode and said workpiece, comprising the steps of: measuring said machining voltage between said electrode and said workpiece; generating a reference voltage; comparing said machining voltage and said reference voltage;
Claim 2
Independent Claim
68 words
A method for automatically increasing the eccentricity of a circular translation movement of an electrode relative to a workpiece, in a spark erosion machine, said movement having a period of travel, a machining voltage being applied between said electrode and said workpiece, comprising the steps of: measuring said machining voltage between said electrode and said workpiece; generating a reference voltage; comparing said machining voltage and said reference voltage;
Claim 3
Dependent Claim
46 words
measuring the time interval during which said machining voltage remains continuously higher than said reference voltage; generating a control signal only said time interval is at least equal to said period of travel; and controlling the increase of said eccentricity in response to said control signal.
Claim 4
Dependent Claim
46 words
measuring the time interval during which said machining voltage remains continuously higher than said reference voltage; generating a control signal only said time interval is at least equal to said period of travel; and controlling the increase of said eccentricity in response to said control signal.
Claim 5
Dependent Claim
152 words
A spark-erosion machine comprising an electrode for machining a workpice, means for applying between said electrode and said workpiece a machining voltage, driving means to drive said electrode and workpiece in a circular translation movement relative to each other, said circular translation movement having an eccentricity and a period of travel, and means for automatically increasing said eccentricity, said means comprising: means for measuring the machining voltage between said electrode and said workpiece; a voltage supply for delivering a reference voltage; comparision means for comparing said machining voltage and said reference voltage; means for measuring the time interval during which said machining voltage has remained continuously higher than said reference voltage; means for generating a control signal only when said time interval is at least equal to said period of travel; and an electric motor controlled by said control signal to act upon said driving means so as to increase said eccentricity.
Claim 6
Dependent Claim
152 words
A spark-erosion machine comprising an electrode for machining a workpice, means for applying between said electrode and said workpiece a machining voltage, driving means to drive said electrode and workpiece in a circular translation movement relative to each other, said circular translation movement having an eccentricity and a period of travel, and means for automatically increasing said eccentricity, said means comprising: means for measuring the machining voltage between said electrode and said workpiece; a voltage supply for delivering a reference voltage; comparision means for comparing said machining voltage and said reference voltage; means for measuring the time interval during which said machining voltage has remained continuously higher than said reference voltage; means for generating a control signal only when said time interval is at least equal to said period of travel; and an electric motor controlled by said control signal to act upon said driving means so as to increase said eccentricity.
Claim 7
Dependent Claim
33 words
A spark-erosion machine according to claim 2, the electrode being carried by a rotating shaft, comprising at least a magnetic lug carried by said shaft and passing in front of a fixed winding.
Claim 8
Dependent Claim
19 words
A spark-erosion machine according to claim 3, said shaft carrying a toothed wheel with a plurality of magnetic teeth.
Claim 9
Dependent Claim
53 words
A spark-erosion machine according to claim 3, said means for generating a control signal being constituted by a two-stage binary counter with an input, an output and a zero-reset connection, said input being connected to said fixed winding, said reset connection being connected to said comparison means and said output to said motor.
Claim 10
Dependent Claim
94 words
A spark-erosion machine according to claim 2, comprising a clock which emits periodic pulses of known period and wherein said means for generating a control signal is constituted by a counter having a predetermined capacity, an input, an output and a zero-reset connection, by an AND gate with two inputs and one output an by a NOR gate, said comparison means being connected to one of said AND gate inputs, and, through said NOR gate to said zero-reset connection of said timer, the other input of said AND gate being connected to said clock.
Claim 11
Dependent Claim
24 words
A spark-erosion machine according to claim 6, said capacity of said timer, for a determined clock pulses period, corresponding to said period of travel.
Claim 12
Dependent Claim
14 words
A spark-erosion machine according to claim 2, said electric motor being a stepping motor.
References Cited (Backward Citations)
FR79637E
Cited
FR80012E
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FR80424E
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US3433919A
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US3135852A
Cited
US3539754A
Cited
US3781507A
Cited
US3694599A
Cited
US3825714A
Cited
US3849624A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-08 | 1981-02-07 | 1981-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-08 | 1985-02-07 | 1985-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-08 | 1989-02-07 | 1989-08-09 | $7700.00 | Window Closed / Lapsed |