US3648077A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit for controlling a heat-generating device
Assignee: Athena Controls Inc
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Filing: 1969-12-03
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Granted: 1972-03-07
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Expires: 1989-12-03
Abstract
Abstract The present circuit employs the combination of a balanced bridge and a balanced differential amplifier to effect a continuous control of energy being supplied to a heat-generating device. The present circuit, in effecting said continuous control, has the capability of rapidly turning on said heat generating device and rapidly turning off said heat-generating device as well as effecting controls at all of the levels in between. A first electronic switch is coupled to the combination of a balanced bridge and a balanced differential amplifier and is responsive to the output therefrom to in turn trigger a second electronic switch which actually operates to permit energy to be transferred to the heating device. In addition, the present circuit employs a means to generate a substantially square wave input which serves to effect better regulation of the system. Further, the present circuit is designed to electrically isolate the load circuit from the control circuit.
Inventors
- 👤 Egils Evalds
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:02
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/20; G05D23/24; G05D23/1906
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
293 words
A circuit for controlling a heat-generating device comprising in combination a bridge circuit having first and second input sides and first and second output terminals, one leg of said bridge circuit being a temperature-responsive element; capacitor means having first and second terminals; first and second transistor means each having a base element, an emitter element and a collector element, said base element of said first transistor connected to said first output terminal, said base element of said second transistor connected to said second output terminal, said emitter elements of said first and second transistors circuitry connected in common to said first input side of said bridge circuit, said first terminal of said capacitor means connected to said collector of said first transistor and said second terminal of said capacitor means connected to said second side of said bridge and said collector of said second transistor; unijunction transistor means having a control element, input element and an output element, said control element connected to said first terminal of said capacitor means, said input element connected to said first side of said bridge; pulse transformer means having a primary winding and a secondary winding, said primary winding connected across said output element of said unijunction transistor and said second side of said bridge; triac means having a control element and connected to provide electrical power to said heat-generating means, said control element of said triac means connected to said secondary winding of said pulse transformer whereby when the temperature affecting said temperature-responsive element changes the current flow through said first and said second transistor shifts thereby changing the time at which said capacitor means is sufficiently charged to cause said unijunction transistor to conduct and therefore said triac to provide power to said heating element.
Claim 2
Dependent Claim
293 words
A circuit for controlling a heat-generating device comprising in combination a bridge circuit having first and second input sides and first and second output terminals, one leg of said bridge circuit being a temperature-responsive element; capacitor means having first and second terminals; first and second transistor means each having a base element, an emitter element and a collector element, said base element of said first transistor connected to said first output terminal, said base element of said second transistor connected to said second output terminal, said emitter elements of said first and second transistors circuitry connected in common to said first input side of said bridge circuit, said first terminal of said capacitor means connected to said collector of said first transistor and said second terminal of said capacitor means connected to said second side of said bridge and said collector of said second transistor; unijunction transistor means having a control element, input element and an output element, said control element connected to said first terminal of said capacitor means, said input element connected to said first side of said bridge; pulse transformer means having a primary winding and a secondary winding, said primary winding connected across said output element of said unijunction transistor and said second side of said bridge; triac means having a control element and connected to provide electrical power to said heat-generating means, said control element of said triac means connected to said secondary winding of said pulse transformer whereby when the temperature affecting said temperature-responsive element changes the current flow through said first and said second transistor shifts thereby changing the time at which said capacitor means is sufficiently charged to cause said unijunction transistor to conduct and therefore said triac to provide power to said heating element.
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) | 1975-03-07 | 1975-09-06 | 1976-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-07 | 1979-09-06 | 1980-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-07 | 1983-09-06 | 1984-03-07 | $7700.00 | Window Closed / Lapsed |