US3814890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave oven having a magnetron extending directly into the oven cavity
Assignee: Northrop Grumman Guidance and Electronics Co Inc
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Filing: 1973-05-16
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Granted: 1974-06-04
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Expires: 1993-05-16
Abstract
Abstract A microwave oven is disclosed which eliminates the need for a wave guide and mechanical stirrer while achieving an even distribution of microwave energy within the oven cavity. The microwave oven comprises a housing having an oven cavity defined by conductively bound surfaces. One of the surfaces, preferably the bottom surface, is of a horn-like structure having diverging surfaces facing the interior of the cavity. An aperture is located at the center portion of the horn-like structure to receive the radiating portion of a magnetron tube to enable the magnetron to feed microwave energy directly into the oven cavity. The outer portion of the diverging surfaces adjoins a cylindrical surface, the radius of the cylinder being a multiple of the wave length of the radiated microwaves.
Inventors
- 👤 E Klemp
- 👤 V Cassibo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:35
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/72
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
76 words
A microwave oven comprising: an oven cavity defined by conductively bounded surfaces; one of said surfaces extending toward adjoining surfaces at internal angles which are greater than 90*, said one surface forming a turncated cone having an aperture formed at the truncated end of said cone; and a source of microwave energy mounted adjacent said one surface, said source of microwave energy comprising a magnetron having a radiating portion extending through said aperture into said cavity.
Claim 2
Dependent Claim
76 words
A microwave oven comprising: an oven cavity defined by conductively bounded surfaces; one of said surfaces extending toward adjoining surfaces at internal angles which are greater than 90*, said one surface forming a turncated cone having an aperture formed at the truncated end of said cone; and a source of microwave energy mounted adjacent said one surface, said source of microwave energy comprising a magnetron having a radiating portion extending through said aperture into said cavity.
Claim 3
Dependent Claim
17 words
The invention of claim 1 wherein the outer periphery of said one surface adjoins a cylindrical surface.
Claim 4
Dependent Claim
23 words
The invention of claim 2 wherein the radius of said cylindrical surface is a multiple of the wavelength of the emanating microwave energy.
Claim 5
Dependent Claim
13 words
The invention of claim 1 wherein said conical surface adjoins a cylindrical surface.
Claim 6
Dependent Claim
23 words
The invention of claim 4 wherein the radius of said cylindrical surface is a multiple of the wavelength of the emanating microwave energy.
Claim 7
Dependent Claim
82 words
A microwave oven comprising: an oven cavity defined by conductively bounded surfaces; one of said surfaces forming a horn-like structure having diverging surfaces facing the interior of said cavity, said diverging surfaces having opposed angles of less than 180*, tHe central portion of said horn-like structure further including an aperture formed therein; and a source of microwave energy mounted within said horn-like structure, said source of microwave energy comprising a magnetron having a radiating portion extending through said aperture into said cavity.
Claim 8
Dependent Claim
82 words
A microwave oven comprising: an oven cavity defined by conductively bounded surfaces; one of said surfaces forming a horn-like structure having diverging surfaces facing the interior of said cavity, said diverging surfaces having opposed angles of less than 180*, tHe central portion of said horn-like structure further including an aperture formed therein; and a source of microwave energy mounted within said horn-like structure, said source of microwave energy comprising a magnetron having a radiating portion extending through said aperture into said cavity.
Claim 9
Dependent Claim
67 words
A microwave oven comprising: an oven cavity defined by conductively bounded surfaces; one of said surfaces extending toward adjoining surfaces at internal angles which are greater than 90*, said one surface further including an aperture formed therein; and a source of microwave energy mounted adjacent said one surface, said source of microwave energy comprising a magnetron having a radiating portion extending through said aperture into said cavity.
Claim 10
Dependent Claim
67 words
A microwave oven comprising: an oven cavity defined by conductively bounded surfaces; one of said surfaces extending toward adjoining surfaces at internal angles which are greater than 90*, said one surface further including an aperture formed therein; and a source of microwave energy mounted adjacent said one surface, said source of microwave energy comprising a magnetron having a radiating portion extending through said aperture into said cavity.
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) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |