US4047096A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for instantly compensating for line voltage irregularities
Assignee: Combustion Engineering Inc
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Filing: 1976-06-15
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Granted: 1977-09-06
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Expires: 1996-06-15
Abstract
Abstract An apparatus for compensating for line voltage variations in a pulsed welding arc supply. A circuit for drawing a current that is proportional to that part of the supply voltage in excess of a predetermined reference is drawn from the capacitor charging circuit in a UJT triggering device. Thus, the more the line voltage exceeds the desired level, the greater is the compensating current withdrawn from the capacitor charging circuit. As a result, the average welding current remains at the desired level despite supply-voltage variations.
Inventors
- 👤 George Robison Madewell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:59
CPC Classifications
B; B23; B23K; B23K9/00; B23K9/06; B23K9/073; B23K9/0732; G; G05; G05F; G05F5/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
137 words
In a current control circuit of the type that triggers means for permitting current from a supply voltage when the charge on a capacitor reaches a trigger level, the capacitor being charged by a charging current, at least part of which is caused by a charging-voltage source and a first series resistance in series with the charging-voltage source that are connected across the capacitor, the improvement comprising: a. a second series resistance connected in series with the charging-voltage source, the first series resistance, and the capacitor; and b. means, connected across the second series resistance, thereby forming a loop comprising itself and the second series resistance, and including a second voltage source whose value is essentially proportional to the instantaneous value of a rectified version of the supply voltage, for causing current to flow in the loop.
Claim 2
Dependent Claim
137 words
In a current control circuit of the type that triggers means for permitting current from a supply voltage when the charge on a capacitor reaches a trigger level, the capacitor being charged by a charging current, at least part of which is caused by a charging-voltage source and a first series resistance in series with the charging-voltage source that are connected across the capacitor, the improvement comprising: a. a second series resistance connected in series with the charging-voltage source, the first series resistance, and the capacitor; and b. means, connected across the second series resistance, thereby forming a loop comprising itself and the second series resistance, and including a second voltage source whose value is essentially proportional to the instantaneous value of a rectified version of the supply voltage, for causing current to flow in the loop.
Claim 3
Dependent Claim
109 words
An apparatus as recited in claim 1 wherein the means for causing a current to flow in the loop further include means, having a first terminal and a second terminal and connected in series with the second voltage source and the second series resistance, for maintaining a relatively high incremental impedance between the first terminal and the second terminal when the voltage drop from the first terminal to the second terminal is below a threshold value and for maintaining a relatively low incremental impedance between the first terminal and the second terminal when the voltage drop from the first terminal to the second terminal is above the threshold value.
Claim 4
Independent Claim
136 words
A method for improving the operation of a current control circuit of the type that triggers a means for permitting current from a supply voltage when the charge on a capacitor reaches a trigger level, the capacitor being charged by a charging current, at least a part of which charging current is caused by a charging circuit connected across the capacitor, which charging circuit includes, in series, a charging-voltage source, a first series resistance, and a second series resistance, the charging-voltage source thereby causing an uncompensated voltage drop across the second series resistance, comprising the step of impressing a compensating voltage across the second series resistance when the compensating voltage exceeds the uncompensated voltage across the second series resistance, the compensating voltage being proportional to the amount by which the supply voltage exceeds a threshold value.
Claim 5
Independent Claim
136 words
A method for improving the operation of a current control circuit of the type that triggers a means for permitting current from a supply voltage when the charge on a capacitor reaches a trigger level, the capacitor being charged by a charging current, at least a part of which charging current is caused by a charging circuit connected across the capacitor, which charging circuit includes, in series, a charging-voltage source, a first series resistance, and a second series resistance, the charging-voltage source thereby causing an uncompensated voltage drop across the second series resistance, comprising the step of impressing a compensating voltage across the second series resistance when the compensating voltage exceeds the uncompensated voltage across the second series resistance, the compensating voltage being proportional to the amount by which the supply voltage exceeds a threshold value.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-05 | 1981-03-07 | 1981-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-05 | 1985-03-07 | 1985-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-05 | 1989-03-07 | 1989-09-06 | $7700.00 | Window Closed / Lapsed |