US3694599A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for digitally controlling the magnitude of a machining gap in an edm process
Assignee: Milacron Inc
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Filing: 1971-11-08
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Granted: 1972-09-26
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Expires: 1991-11-08
Abstract
Abstract An apparatus is disclosed for detecting the exclusive occurrence of a voltage pulse or a current pulse during an EDM machining process. A machining gap is decreased a predetermined increment in response to a predetermined number of consecutive occurrences of only voltage pulses. Further, the machining gap is increased a number of predetermined increments in response to a predetermined number of consecutive occurrences of only current pulses; and finally, the machining process is terminated in response to the gap increasing in magnitude.
Inventors
- 👤 Malcolm F Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:34
CPC Classifications
B; B23; B23H; B23H7/00; B23H7/14; B23H7/18
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
219 words
An apparatus for controlling a digital drive circuit connected to a digital driving mechanism for producing relative motion between an electrically conductive tool and an electrically conductive workpiece positioned to form a machining gap therebetween, said machining gap having current pulses periodically passed thereacross in response to voltage pulses being provided by a power supply, the apparatus comprising: a. means connected to the power supply for detecting the voltage and current pulses; b. means connected to the detecting means for generating 1. an advance signal in response to a predetermined number of consecutive occurrences of only voltage pulses, and 2. a retract signal in response to a predetermined number of consecutive occurrences of only current pulses; and c. means connected to the generating means, the digital drive circuit and the power supply for producing 1. a first command signal being supplied to the digital drive circuit in response to the retract signal for moving the tool a predetermined number of digital increments away from the workpiece, 2. a second command signal being supplied to the digital drive circuit in response to the advance signal for moving the tool a digital increment toward the workpiece, and 3. a control signal being supplied to the power supply in response to the retract signal for terminating the supply of voltage pulses therefrom.
Claim 2
Independent Claim
219 words
An apparatus for controlling a digital drive circuit connected to a digital driving mechanism for producing relative motion between an electrically conductive tool and an electrically conductive workpiece positioned to form a machining gap therebetween, said machining gap having current pulses periodically passed thereacross in response to voltage pulses being provided by a power supply, the apparatus comprising: a. means connected to the power supply for detecting the voltage and current pulses; b. means connected to the detecting means for generating 1. an advance signal in response to a predetermined number of consecutive occurrences of only voltage pulses, and 2. a retract signal in response to a predetermined number of consecutive occurrences of only current pulses; and c. means connected to the generating means, the digital drive circuit and the power supply for producing 1. a first command signal being supplied to the digital drive circuit in response to the retract signal for moving the tool a predetermined number of digital increments away from the workpiece, 2. a second command signal being supplied to the digital drive circuit in response to the advance signal for moving the tool a digital increment toward the workpiece, and 3. a control signal being supplied to the power supply in response to the retract signal for terminating the supply of voltage pulses therefrom.
Claim 3
Dependent Claim
34 words
a retract signal in response to a predetermined number of consecutive occurrences of only current pulses; and c. means connected to the generating means, the digital drive circuit and the power supply for producing
Claim 4
Dependent Claim
34 words
a retract signal in response to a predetermined number of consecutive occurrences of only current pulses; and c. means connected to the generating means, the digital drive circuit and the power supply for producing
Claim 5
Dependent Claim
28 words
a second command signal being supplied to the digital drive circuit in response to the advance signal for moving the tool a digital increment toward the workpiece, and
Claim 6
Dependent Claim
28 words
a second command signal being supplied to the digital drive circuit in response to the advance signal for moving the tool a digital increment toward the workpiece, and
Claim 7
Independent Claim
208 words
An apparatus for use on an EDM machine comprised in part of a digital drive circuit being responsive to the control circuit for energizing a digital driving mechanism to control the magnitude of a machining gap formed between an electrically conductive tool and an electrically conductive workpiece, said machining gap being supplied voltage pulses from a power supply containing an output switching circuit and a switching means for selectively initiating and terminating the supply of said voltage pulses, wherein the improvement comprises: a. means connected to the output switching circuit for detecting a voltage pulse and providing a voltage detection pulse as a function thereof; b. means connected to the output switching circuit for detecting a current pulse in response to a voltage pulse and providing a current detection pulse as a function thereof; c. means connected to the detecting means for generating an advance signal in response to the detection of an exclusive occurrence of a predetermined number of consecutive voltage pulses and a retract signal in response to the detection of an exclusive occurrence of a predetermined number of consecutive current pulses; and d. means having inputs connected to the generating means and outputs connected to the digital drive circuit and the switching means and producing
Claim 8
Independent Claim
208 words
An apparatus for use on an EDM machine comprised in part of a digital drive circuit being responsive to the control circuit for energizing a digital driving mechanism to control the magnitude of a machining gap formed between an electrically conductive tool and an electrically conductive workpiece, said machining gap being supplied voltage pulses from a power supply containing an output switching circuit and a switching means for selectively initiating and terminating the supply of said voltage pulses, wherein the improvement comprises: a. means connected to the output switching circuit for detecting a voltage pulse and providing a voltage detection pulse as a function thereof; b. means connected to the output switching circuit for detecting a current pulse in response to a voltage pulse and providing a current detection pulse as a function thereof; c. means connected to the detecting means for generating an advance signal in response to the detection of an exclusive occurrence of a predetermined number of consecutive voltage pulses and a retract signal in response to the detection of an exclusive occurrence of a predetermined number of consecutive current pulses; and d. means having inputs connected to the generating means and outputs connected to the digital drive circuit and the switching means and producing
Claim 9
Dependent Claim
32 words
a second set of command signals being applied to the digital drive circuit in response to the advance signals for decreasing the size of the machining gap by a digital increment, and
Claim 10
Dependent Claim
32 words
a second set of command signals being applied to the digital drive circuit in response to the advance signals for decreasing the size of the machining gap by a digital increment, and
Claim 11
Dependent Claim
128 words
a second pulse in response to the exclusive occurrence of a current pulse; b. first means connected to the gating network and having a first input responsive to the first pulse for counting the occurrences of said first pulse, said first means having a reset input responsive to the second pulse and providing the advance signal in response to counting a predetermined number of consecutive occurrences of said first pulses; and c. second means connected to the gating network and having a first input responsive to the second pulse for counting the occurrences of said second pulse, said second means having a reset input responsive to the first pulse and providing the retract signal in response to counting a predetermined number of consecutive occurrences of said second pulses.
Claim 12
Dependent Claim
128 words
a second pulse in response to the exclusive occurrence of a current pulse; b. first means connected to the gating network and having a first input responsive to the first pulse for counting the occurrences of said first pulse, said first means having a reset input responsive to the second pulse and providing the advance signal in response to counting a predetermined number of consecutive occurrences of said first pulses; and c. second means connected to the gating network and having a first input responsive to the second pulse for counting the occurrences of said second pulse, said second means having a reset input responsive to the first pulse and providing the retract signal in response to counting a predetermined number of consecutive occurrences of said second pulses.
Claim 13
Dependent Claim
25 words
a control signal for energizing the switching means to terminate the supply of voltage pulses for the duration of the first set of command signals.
Claim 14
Dependent Claim
25 words
a control signal for energizing the switching means to terminate the supply of voltage pulses for the duration of the first set of command signals.
Claim 15
Dependent Claim
23 words
The apparatus of claim 2 wherein the generating means comprises: a. a gating network responsive to the voltage and current pulses for providing
Claim 16
Dependent Claim
23 words
a control signal being supplied to the power supply in response to the retract signal for terminating the supply of voltage pulses therefrom.
Claim 17
Dependent Claim
23 words
a control signal being supplied to the power supply in response to the retract signal for terminating the supply of voltage pulses therefrom.
Claim 18
Dependent Claim
159 words
The apparatus of claim 3 wherein the producing means comprises: a. storing means connected to the switching means and responsive to the retract signal for producing a control signal, said control signal energizing the switching means for terminating the supply of voltage pulses; b. means connected to the digital drive circuit and responsive to the retract signal and the advance signal for producing the first set of command signals comprised of a direction signal and a number of digital signals, each digital signal representing a predetermined increment of motion of the digital driving mechanism, and the second set of command signals comprised of an inversion of the direction signal and one of the digital signals; and c. means connected to the storing means and responsive to the number of digital signals for counting the digital signals and producing an output signal being operative to terminate the control signal in response to counting a predetermined number of said digital signals.
References Cited (Backward Citations)
US3340478A
Cited
US3381107A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-26 | 1976-03-27 | 1976-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-26 | 1980-03-27 | 1980-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-26 | 1984-03-27 | 1984-09-26 | $7700.00 | Window Closed / Lapsed |