Patent US3739137A successfully refreshed from Google Patents.
US3739137A
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Process and apparatus for machining by electro erosion
Assignee: Ateliers des Charmilles SA
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Filing: 1972-03-22
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Granted: 1973-06-12
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Expires: 1992-03-22
Abstract
Abstract A process and installation for machining by electro-erosion, comprising means for measuring the rate of variation of the voltage of the machining gap during the establishment of each discharge, these means acting upon the electrical and/or the mechanical control of the installation.
Inventors
- 👤 G Marendaz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:18
CPC Classifications
B; B23; B23H; B23H1/00; B23H1/02; B23H1/024
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
193 words
A machining process by electro-erosion according to which a succession of voltage pulses are applied within a machining gap comprised between an electrode-part to be machined and an electrode-tool intended to trigger the erosive discharges through a machining fluid filling the gap, the discharges being sustained by controlled current pulses, and in which at least one of the following machining parameters is controlled automatically: first, the characteristic value of said electric voltage and/or current pulses; second, the physical or chemical condition of the machining fluid filling the said gap; and third, The spacing of said electrodes; by means of electric signals obtained from measurements of the voltage between the electrodes and/or the current flowing through the latter and/or a combination of both of said signals, said process comprising detecting the decrease of said voltage, during the establishment of the current pulses when at a rate which is inferior to that of a predetermined value, and acting upon at least one of the machining parameters in response to an electric signal resulting from the presence of the decrease of the voltage when at a rate which is inferior to that of said predetermined value.
Claim 2
Dependent Claim
193 words
A machining process by electro-erosion according to which a succession of voltage pulses are applied within a machining gap comprised between an electrode-part to be machined and an electrode-tool intended to trigger the erosive discharges through a machining fluid filling the gap, the discharges being sustained by controlled current pulses, and in which at least one of the following machining parameters is controlled automatically: first, the characteristic value of said electric voltage and/or current pulses; second, the physical or chemical condition of the machining fluid filling the said gap; and third, The spacing of said electrodes; by means of electric signals obtained from measurements of the voltage between the electrodes and/or the current flowing through the latter and/or a combination of both of said signals, said process comprising detecting the decrease of said voltage, during the establishment of the current pulses when at a rate which is inferior to that of a predetermined value, and acting upon at least one of the machining parameters in response to an electric signal resulting from the presence of the decrease of the voltage when at a rate which is inferior to that of said predetermined value.
Claim 3
Dependent Claim
69 words
A process according to claim 1, wherein means are provided for the detection of the decrease of the voltage, the rate of which is substantially superior to that of the said pre-established value, during the establishment of the current pulses and for obtaining said signal in response to the presence of the decrease of the voltage, the rate of which is sensibly superior to that of the predetermined value.
Claim 4
Dependent Claim
41 words
A process according to claim 1, wherein a predetermined value is given to said electric signal when, during the establishment of the current pulses, a voltage decrease is detected, the rate of which is inferior to that of a predetermined value.
Claim 5
Dependent Claim
50 words
A process according to claim 1, wherein said electric signal is given, at successive instants repeated at a rhythm identical to that of the current pulses, a value, function of the rate of decrease of the voltage at the moments of establishment of the current pulses included between these instants.
Claim 6
Dependent Claim
51 words
A process according to claim 4, wherein said electric signal is given, at said instants, a predetermined value, when the rate of decrease of the voltage is inferior to that of a predetermined value, and another predetermined value, when this rate of decrease is superior to that of a predetermined value.
Claim 7
Dependent Claim
116 words
A process according to claim 1, wherein action, on at least one of the machining parameters is provided, by means of a combination of said signal, obtained in response to the presence of the voltage decrease for which the rate of decrease is inferior to that of a predetermined value, with at least another electric signal elaborated by detecting the abrupt variations of said voltage occuring during the time intervals included between instants corresponding to the beginning of the current pulses and instants corresponding to their ending, exclusive of these instants, this other electric signal being obtained in response to the presence, respectively to the absence of these abrupt variations of voltage during these time intervals.
Claim 8
Dependent Claim
128 words
A process according to claim 1, wherein action is provided on at least one of the machining parameters, by means of a combination of said signal, obtained in response to the presence of a decrease of the voltage, which rate of decrease is inferior to that of a predetermined value, with at least another electric signal, elaborated by effecting repeated measurements of the average level of the voltage between the electrodes during the time intervals included between the instants corresponding to the beginning of the current pulses and the instants corresponding to their ending, by memorizing the result of these measurements and by comparison between them, the results of these measurements from one current pulse to another, the said signal being elaborated from the differences of these results.
Claim 9
Dependent Claim
109 words
A process according to claim 1, wherein action is provided on at least one of the machining parameters, by means of a combination of said signal, obtained in response to the presence of the decrease of the voltage, the rate of which decrease is inferior to that of a predetermined value, with at least one other electric signal elaborated, in known manner, from the comparison of a reference value, with the result of repeated measurements of the average level of the voltage between the electrodes, effected during the time intervals included between the instants corresponding to the bEginning of the current pulses and the instants corresponding to their ending.
Claim 10
Dependent Claim
102 words
A process according to claim 1, wherein action is provided on at least one of the machining parameters, by means of a combination of said signal, obtained in response to the presence of the decrease of the voltage, which rate of decrease is inferior to that of a predetermined value, with at least one other electric signal which is elaborated in a known manner, from the repeated measurements of the voltage between the electrodes effected during the time intervals included between the instants corresponding to the beginning of the tension pulses and the instants corresponding to the beginning of the current pulses.
Claim 11
Dependent Claim
29 words
A process according to claim 1, wherein the chemical or physical conditions of the machining fluid filling the machining space can be altered in response to said electric signal.
Claim 12
Dependent Claim
28 words
A process according to claim 10, wherein the rate of renewal of the machining fluid within the machining space can be altered in response to said electric signal.
Claim 13
Dependent Claim
86 words
An installation for working out the process according to claim 1, wherein first means are comprised, sensitive to the rate of the voltage variations between the electrode-part and the electrode-tool, of an amplitude superior to that of a predetermined value and second means, operatively related to the first means, conceived and disposed in a manner permitting the delivery of a signal intended to act upon at least one of the machining parameters, this signal being obtained in response to the rate of speed of said variations.
Claim 14
Dependent Claim
48 words
An installation according to claim 12, wherein the first and second means are conceived and disposed in a manner allowing the second means to assume two distinct electrical conditions, contingent upon the rate of speed of said variations being superior or inferior to that of a predetermined value.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |