US4196330A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combination oven fully utilizing the current-supplying capability of a power source
Assignee: General Electric Co
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Filing: 1978-06-01
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Granted: 1980-04-01
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Expires: 1998-06-01
Abstract
Abstract A cooking oven having both microwave and electrical resistance heating means and which fully utilizes the capabilities of a limited-capability power source to achieve the shortest possible cooking time. The oven has a microwave energy generating system which requires less than all of the available current when operated at its full rated power level, and an electrical resistance heating element which requires substantially all of the available current when operated at its full rated power level. The oven also has a means for at least successively energizing the microwave energy generating system and the electrical resistance heating element at their respective full rated power levels. Additionally, there is a means for periodically fully energizing the electrical resistance heating element from the power source in short pulses when the microwave energy generating system is energized at its full rated power level. The pulses are of such frequency and duration that the resultant RMS current integrated over at least a period including one pulse and one interval between pulses, when added to the current drawn from the source to operate the microwave energy generating system at its full rated power level is no greater than and, preferably, substantially equal to, the current-supplying capability of the power source.
Inventors
- 👤 Thomas R. Payne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:35
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/647; H05B6/6482; H05B6/6447; H05B6/645
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
214 words
A cooking oven which has both microwave and electrical resistance heating means, which is adapted for operation from a power source of limited current-supplying capability insufficient to concurrently supply both heating means at their respective fully rated power levels, and which comprises: said microwave heating means being a microwave energy generating system requiring less than all of the available current when operated at its full rated power level; said resistance heating means being an electrical resistance heating element requiring substantially all of the available current when operated at its full rated power level; means for successively energizing said microwave energy generating system and said electrical resistance heating element from the power source at their respective full rated power levels; and means for periodically fully energizing said electrical resistance heating element from the power source in short pulses when said microwave energy generating system is energized at its full rated power level, the pulses being of such frequency and duration that the resultant RMS current obtained by integrating the instantaneous current over at least a period including one pulse and one interval between pulses when added to the current drawn from the source to operate said microwave energy generating system at its full rated power level is no greater than the power source current-supplying capability.
Claim 2
Dependent Claim
214 words
A cooking oven which has both microwave and electrical resistance heating means, which is adapted for operation from a power source of limited current-supplying capability insufficient to concurrently supply both heating means at their respective fully rated power levels, and which comprises: said microwave heating means being a microwave energy generating system requiring less than all of the available current when operated at its full rated power level; said resistance heating means being an electrical resistance heating element requiring substantially all of the available current when operated at its full rated power level; means for successively energizing said microwave energy generating system and said electrical resistance heating element from the power source at their respective full rated power levels; and means for periodically fully energizing said electrical resistance heating element from the power source in short pulses when said microwave energy generating system is energized at its full rated power level, the pulses being of such frequency and duration that the resultant RMS current obtained by integrating the instantaneous current over at least a period including one pulse and one interval between pulses when added to the current drawn from the source to operate said microwave energy generating system at its full rated power level is no greater than the power source current-supplying capability.
Claim 3
Dependent Claim
21 words
A cooking oven according to claim 1, wherein the resultant RMS current is substantially equal to the power source current-supplying capability.
Claim 4
Dependent Claim
29 words
A cooking oven according to claim 1, which is adapted for operation from an AC power source, and wherein the pulses are synchronized to the incoming AC voltage waveform.
Claim 5
Dependent Claim
16 words
A cooking oven according to claim 3, wherein each pulse is one-half AC cycle in duration.
Claim 6
Dependent Claim
74 words
A cooking oven according to claim 3, wherein said means for periodically energizing said resistance heating element in short pulses comprises a digital counter connected to count zero crossings of the incoming AC voltage waveform and to output a signal after every n counts to energize said resistance heating element for one-half of an AC cycle, whereby the resultant RMS current is equal to the heating element full power level current divided by √n.
Claim 7
Dependent Claim
62 words
A cooking oven according to claim 1, which is adapted for operation from an AC power source, wherein said microwave energy generating system draws a substantial startup current, and which further comprises a means for delaying the first pulse following energization of said microwave energy generating until said microwave energy generating system is drawing its steady state current from the power source.
Claim 8
Dependent Claim
30 words
A cooking oven according to claim 6, wherein said microwave energy generating system draws a substantial start up current for approximately one full cycle of the incoming AC voltage waveform.
Claim 9
Dependent Claim
93 words
A cooking oven according to claim 7, wherein said means for periodically energizing said resistance heating element in short pulses comprises: a digital counter connected to count zero crossings of the incoming AC voltage waveform and to output a signal after every n counts to energize said resistance heating element for one-half of an AC cycle, whereby the resultant RMS current is equal to the heating element full power level current divided by √n; and means for resetting said digital counter to its initial count upon energization of said microwave energy generating system.
Claim 10
Dependent Claim
38 words
A cooking oven according to claim 1, wherein there are a plurality of successive energizations of said microwave energy generating system and said electrical resistance heating element at their respective full rated power levels during a cooking operation.
Claim 11
Dependent Claim
21 words
A cooking oven according to claim 9, wherein the resultant RMS current is substantially equal to the power source current-supplying capability.
Claim 12
Dependent Claim
29 words
A cooking oven according to claim 9, which is adapted for operation from an AC power source, and wherein the pulses are synchronized to the incoming AC voltage waveform.
Claim 13
Dependent Claim
16 words
A cooking oven according to claim 11, wherein each pulse is one-half AC cycle in duration.
Claim 14
Dependent Claim
74 words
A cooking oven according to claim 11, wherein said means for periodically energizing said resistance heating element in short pulses comprises a digital counter connected to count zero crossings of the incoming AC voltage waveform and to output a signal after every n counts to energize said resistance heating element for one-half of an AC cycle, whereby the resultant RMS current is equal to the heating element full power level current divided by √n.
Claim 15
Dependent Claim
63 words
A cooking oven according to claim 9, which is adapted for operation from an AC power source, wherein said microwave energy generating system draws a substantial startup current, and which further comprises a means for delaying the first pulse following energization of said microwave energy generating system until said microwave energy generating system is drawing its steady state current from the power source.
Claim 16
Dependent Claim
30 words
A cooking oven according to claim 14, wherein said microwave energy generating system draws a substantial start up current for approximately one full AC cycle of the incoming voltage waveform.
Claim 17
Dependent Claim
93 words
A cooking oven according to claim 15, wherein said means for periodically energizing said resistance heating element in short pulses comprises: a digital counter connected to count zero crossings of the incoming AC voltage waveform and to output a signal after every n counts to energize said resistance heating element for one-half of an AC cycle, whereby the resultant RMS current is equal to the heating element full power level current divided by √n; and means for resetting said digital counter to its initial count upon energization of said microwave energy generating system.
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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) | 1983-04-01 | 1983-10-01 | 1984-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-01 | 1987-10-01 | 1988-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-01 | 1991-10-01 | 1992-04-01 | $7700.00 | Window Closed / Lapsed |