US4764663A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric radiation heater assemblies
Assignee: Micropore International Ltd
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Filing: 1987-01-27
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Granted: 1988-08-16
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Expires: 2007-01-27
Abstract
Abstract An electric radiation heater assembly for a glass ceramic top cooker includes at least one heating element having a substantial positive temperature coefficient of resistance, such as an infra-red lamp. A resistive assembly is electrically connected in series with the at least one heating element for suppressing surges of electric current due to the low initial resistance of the heating element. Switch means is operable a time interval of at least thirty milliseconds and preferably about 1/2 second after a supply of electric power to the heater is energized so as to reduce the combined electrical resistance of the heating element and the resistive assembly.
Inventors
- 👤 Richard C. Scott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:26
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/68; H05B3/74; H05B3/742
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
157 words
An electric radiation heater assembly comprising: at least one heating element having a substantial positive temperature coefficient of resistance; a resistive assembly electrically connected in series with said at least one heating element for suppressing surge of electric current due to said at least one heating element, said resistive assembly comprising two resistive elements electrically connected in parallel; means for supplying electric power to said at least one heating element and to said resistive assembly; and switch means operable a time interval of at least thirty milliseconds after a supply of electric power to said at least one heating element and to said resistive assembly is energised such that one of said resistive elements is electrically open-circuit until said time interval has expired and is thereafter electrically connected in parallel with the other of said resistive elements so as to reduce the combined electrical resistance of said at least one heating element and of said resistive assembly.
Claim 2
Dependent Claim
157 words
An electric radiation heater assembly comprising: at least one heating element having a substantial positive temperature coefficient of resistance; a resistive assembly electrically connected in series with said at least one heating element for suppressing surge of electric current due to said at least one heating element, said resistive assembly comprising two resistive elements electrically connected in parallel; means for supplying electric power to said at least one heating element and to said resistive assembly; and switch means operable a time interval of at least thirty milliseconds after a supply of electric power to said at least one heating element and to said resistive assembly is energised such that one of said resistive elements is electrically open-circuit until said time interval has expired and is thereafter electrically connected in parallel with the other of said resistive elements so as to reduce the combined electrical resistance of said at least one heating element and of said resistive assembly.
Claim 3
Dependent Claim
18 words
A heater assembly according to claim 1, wherein said at least one heating element comprises two heating elements.
Claim 4
Dependent Claim
18 words
A heater assembly according to claim 1, wherein said at least one heating element comprises an infra-red lamp.
Claim 5
Dependent Claim
28 words
A heater assembly according to claim 1, wherein the switch means comprises a relay including an actuating coil which is connected across said at least one heating element.
Claim 6
Dependent Claim
22 words
A heater assembly according to claim 1, wherein the switch means comprises a PTC thermistor in combination with a bi-metallic snap switch.
Claim 7
Dependent Claim
18 words
A heater assembly according to claim 1, wherein the time interval is from thirty milliseconds to 10 seconds.
Claim 8
Dependent Claim
15 words
A heater assembly according to claim 6, wherein the time interval is about 1/2 second.
Claim 9
Dependent Claim
136 words
An electric radiation heater assembly comprising: at least one heating element having a substantial positive temperature coefficient of resistance; a resistive assembly electrically connected in series with said at least one heating element for suppressing surge of electric current due to said at least one heating element; means for supplying electric power to said at least one heating element and to said resistive assembly; and switch means operable a time interval of at least thirty milliseconds after a supply of electric power to said at least one heating element and to said resistive assembly is energised so as to reduce the combined electrical resistance of said at least one heating element and of said resistive assembly, said switch means comprising a relay including an actuating coil which is connected across said at least one heating element.
Claim 10
Dependent Claim
136 words
An electric radiation heater assembly comprising: at least one heating element having a substantial positive temperature coefficient of resistance; a resistive assembly electrically connected in series with said at least one heating element for suppressing surge of electric current due to said at least one heating element; means for supplying electric power to said at least one heating element and to said resistive assembly; and switch means operable a time interval of at least thirty milliseconds after a supply of electric power to said at least one heating element and to said resistive assembly is energised so as to reduce the combined electrical resistance of said at least one heating element and of said resistive assembly, said switch means comprising a relay including an actuating coil which is connected across said at least one heating element.
Claim 11
Dependent Claim
18 words
A heater assembly according to claim 8, wherein said at least one heating element comprises two heating elements.
Claim 12
Dependent Claim
18 words
A heater assembly according to claim 8, wherein said at least one heating element comprises an infra-red lamp.
Claim 13
Dependent Claim
33 words
A heater assembly according to claim 8, wherein the resistive assembly comprises a single resistive element positioned within a body of the heater, the resistive element being electrically short-circuited after said time interval.
Claim 14
Dependent Claim
34 words
A heater assembly according to claim 8, wherein the resistive assembly comprises a single resistive element positioned externally of a body of the heater, the resistive element being electrically short-circuited after said time interval.
Claim 15
Dependent Claim
33 words
A heater assembly according to claim 8, wherein the resistive assembly comprises two resistive elements electrically connected in parallel, one of said resistive elements being electrically open-circuit until said time interval has expired.
Claim 16
Dependent Claim
18 words
A heater assembly according to claim 8, wherein the time interval is from thirty milliseconds to 10 seconds.
Claim 17
Dependent Claim
15 words
A heater assembly according to claim 14, wherein the time interval is about 1/2 second.
Claim 18
Dependent Claim
129 words
An electric radiation heater assembly comprising: at least one heating element having a substantial positive temperature coefficient of resistance; a resistive assembly electrically connected in series with said at least one heating element for suppressing surge of electric current due to said at least one heating element; means for supplying electric power to said at least one heating element and to said resistive assembly; and switch means operable a time interval of at least thirty milliseconds after a supply of electric power to said at least one heating element and said resistive assembly is energised so as to reduce the combined electrical resistance of said at least one heating element and of said resistive assembly, said switch means comprising a PTC thermistor in combination with a bi-metallic snap switch.
Claim 19
Dependent Claim
129 words
An electric radiation heater assembly comprising: at least one heating element having a substantial positive temperature coefficient of resistance; a resistive assembly electrically connected in series with said at least one heating element for suppressing surge of electric current due to said at least one heating element; means for supplying electric power to said at least one heating element and to said resistive assembly; and switch means operable a time interval of at least thirty milliseconds after a supply of electric power to said at least one heating element and said resistive assembly is energised so as to reduce the combined electrical resistance of said at least one heating element and of said resistive assembly, said switch means comprising a PTC thermistor in combination with a bi-metallic snap switch.
Claim 20
Dependent Claim
19 words
A heat assembly according to claim 16, wherein said at least one heating heating element comprises two heating elements.
Claim 21
Dependent Claim
18 words
A heater assembly according to claim 16, wherein said at least one heating element comprises an infra-red lamp.
Claim 22
Dependent Claim
33 words
A heater assembly according to claim 16, wherein the resistive assembly comprises two resistive elements electrically connected in parallel, one of said resistive elements being electrically open-circuit until said time interval has expired.
Claim 23
Dependent Claim
18 words
A heater assembly according to claim 16, wherein the time interval is from thirty milliseconds to 10 seconds.
Claim 24
Dependent Claim
15 words
A heater assembly according to claim 20, wherein the time interval is about 1/2 second.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-08-16 | 1992-02-15 | 1992-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-16 | 1996-02-15 | 1996-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-16 | 2000-02-15 | 2000-08-16 | $7700.00 | Window Closed / Lapsed |