Patent US3855440A successfully refreshed from Google Patents.
US3855440A
Expired / Lapsed
US
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Microwave oven having preferred modes
Assignee: General Electric Co
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Filing: 1974-01-04
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Granted: 1974-12-17
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Expires: 1994-01-04
Abstract
Abstract A counter-top microwave oven comprises an upstanding box-like metal wall structure defining a heating cavity, a microwave generator including a voltage quadrupler power supply, and transmission means including a probe antenna for radiating the microwaves into the heating cavity, the cavity being so dimensioned and the antenna being so positioned as to excite in said cavity preferred electromagnetic field modes for establishing preferred field patterns to achieve uniform heating of a variety of foods. A first embodiment of the heating cavity is dimensioned to produce two complementary modes of which establish an undistorted field pattern providing uniform heating over a distance greater than a wavelength of the source microwave energy, tuning means being provided to tune undesired modes of resonance. A second embodiment of the oven is dimensioned to produce a single electromagnetic field mode producing a field pattern which provides uniform heating over a distance less than a wavelength of the source microwave energy. Several forms of each embodiment of the invention are disclosed.
Inventors
- 👤 J Staats
- 👤 L Fitzmayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:00
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/66; H05B6/666; H05B6/6402; H05B6/642; H05B6/647; H05B6/6482; H05B6/70; H05B6/705; H05B6/72; H05B6/725; H05B6/76; H05B6/766; Y; Y02; Y02B; Y02B40/00
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
134 words
Electronic heating apparatus comprising a metal enclosure including six rectangular walls arranged to form a rectangular parallelepiped defining a heating cavity for receiving therein a body to be heated, and source means for transmitting microwave energy of a predetermined wavelength through one of said walls into said heating cavity for exciting therein a predetermined electromagnetic field mode, said one wall having an electrical dimension D such that D > OR = 1.1 n lambda /2 wherein n is any integer and lambda is said predetermined wavelength, said predetermined electromagnetic field mode having the fields thereof constant in directions normal to said one wall with power flow being parallel to the direction of the dimension D, whereby there is established in said heating cavity an electromagnetic field pattern providing uniform heating of an associated body.
Claim 2
Dependent Claim
134 words
Electronic heating apparatus comprising a metal enclosure including six rectangular walls arranged to form a rectangular parallelepiped defining a heating cavity for receiving therein a body to be heated, and source means for transmitting microwave energy of a predetermined wavelength through one of said walls into said heating cavity for exciting therein a predetermined electromagnetic field mode, said one wall having an electrical dimension D such that D > OR = 1.1 n lambda /2 wherein n is any integer and lambda is said predetermined wavelength, said predetermined electromagnetic field mode having the fields thereof constant in directions normal to said one wall with power flow being parallel to the direction of the dimension D, whereby there is established in said heating cavity an electromagnetic field pattern providing uniform heating of an associated body.
Claim 3
Dependent Claim
17 words
The electronic heating apparatus set forth in claim 1, wherein lambda is approximately equal to 12.9 inches.
Claim 4
Dependent Claim
18 words
The electronic heating apparatus set forth in claim 1, wherein said predetermined mode is a transverse electric mode.
Claim 5
Dependent Claim
40 words
The electronic heating apparatus set forth in claim 1, wherein said one wall is square with D lambda / Square Root 2, said source means including an antenna disposed centrally of said one wall and projecting into said heating cavity.
Claim 6
Dependent Claim
84 words
The electronic heating apparatus set forth in claim 1, wherein said one wall has an electrical width D and length E such that D 1.1 lambda and E 1.2 lambda , said source means including an antenna projecting through said one wall into said heating cavity at a location spaced a distance D/4 from one of the edges of said one wall having the dimension E and spaced a distance E/2 from one of the edges of said one wall having the dimension D.
Claim 7
Dependent Claim
84 words
The electronic heating apparatus set forth in claim 1, wherein said one wall has an electrical width D and length E such that D 1.1 lambda and E 1.2 lambda , said source means including an antenna projecting through said one wall into said heating cavity at a location spaced a distance D/4 from one of the edges of said one wall having the dimension E and spaced a distance E/4 from one of the edges of said one wall having the dimension D.
Claim 8
Dependent Claim
79 words
The electronic heating apparatus set forth in claim 1, and further including a shelf including a plurality of parallel spaced apart metal rods interconnected at the ends thereof and disposed in said heating cavity substantially perpendicular to the electric field for supporting the associated body to be heated, said shelf being selectively mountable at a plurality of different positions in said heating cavity for varying the position of the associated body with respect to the electromagnetic field pattern therein.
Claim 9
Dependent Claim
62 words
The electronic heating apparatus set forth in claim 1, wherein said source means includes an antenna projecting through said one wall into the heating cavity, said antenna including a short cylindrical member disposed substantially perpendicular to said one wall and a circular disc connected to said cylindrical member at the inner end thereof cpncentric therewith and normal to the longitudinal axis thereof.
Claim 10
Dependent Claim
160 words
Electronic heating appAratus comprising a metal enclosure in the form of a rectangular parallelepiped including a top wall, a bottom wall, a front wall, a rear wall and two opposed side walls defining a heating cavity for receiving therein a body to be heated, and source means electrically coupled to said heating cavity at a location along said rear wall in the upper half thereof, said source means transmitting microwave energy of a predetermined wavelength into said heating cavity for exciting therein two predetermined complementary electromagnetic field modes, at least one of said predetermined electromagnetic field modes having the fields thereof constant in a direction parallel to one of the dimensions of said heating cavity, each of said predetermined electromagnetic field modes having the fields thereof varying in the direction in which the fields of the other mode are constant, whereby there is established in said heating cavity an undistorted electromagnetic field pattern providing uniform heating of an associated body.
Claim 11
Dependent Claim
160 words
Electronic heating appAratus comprising a metal enclosure in the form of a rectangular parallelepiped including a top wall, a bottom wall, a front wall, a rear wall and two opposed side walls defining a heating cavity for receiving therein a body to be heated, and source means electrically coupled to said heating cavity at a location along said rear wall in the upper half thereof, said source means transmitting microwave energy of a predetermined wavelength into said heating cavity for exciting therein two predetermined complementary electromagnetic field modes, at least one of said predetermined electromagnetic field modes having the fields thereof constant in a direction parallel to one of the dimensions of said heating cavity, each of said predetermined electromagnetic field modes having the fields thereof varying in the direction in which the fields of the other mode are constant, whereby there is established in said heating cavity an undistorted electromagnetic field pattern providing uniform heating of an associated body.
Claim 12
Dependent Claim
18 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined complementary modes are transverse electric modes.
Claim 13
Dependent Claim
19 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is approximately equal to 12.9 inches.
Claim 14
Dependent Claim
76 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is lambda , and said heating cavity has a width of 1.2 lambda and a height of 0.633 lambda and a depth of 1.1 lambda , said source means being disposed along said rear wall at a location substantially midway between said side walls and spaced from said top wall a distance approximately equal to one-fourth of the height of said heating cavity.
Claim 15
Dependent Claim
71 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is lambda , and said heating cavity is a cube measuring lambda / Square Root 2 on each side, said source means including an antenna disposed along said rear wall at a location substantially midway between said side walls and spaced from said top wall a distance approximately equal to one-fourth of the height of said heating cavity.
Claim 16
Dependent Claim
100 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is lambda , and said heating cavity has a width of Square Root 2 lambda , and a height of lambda / Square Root 2 and a depth of Square Root 2 lambda , said source means including an antenna disposed along said rear wall at a location spaced from said top wall a distance approximately equal to one-fourth of the height of said heating cavity and spaced from one of said side walls a distance approximately equal to one-fourth of the width of said heating cavity.
Claim 17
Dependent Claim
84 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is lambda , and said heating cavity is a cube measuring Square Root 2 lambda on each side, said source means including an antenna disposed along said rear wall at a location spaced from said top wall a distance approximately equal to one-fourth of the height of said heating cavity and spaced from one of said side walls a distance approximately equal to one-fourth of the width of said heating cavity.
Claim 18
Dependent Claim
86 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is lambda , and said heating cavity has a width of 3 Square Root 2 lambda /2 and a height of lambda / Square Root 2 and a depth of Square Root 2 lambda , said source means including an antenna disposed along said rear wall at a location substantially midway between said side walls spaced from said top wall a distance approximately equal to one-fourth of the height of said heating cavity.
Claim 19
Dependent Claim
78 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is lambda , and said heating cavity has a width of 1.61 lambda and a height of 0.767 lambda and a depth of 1.23 lambda , said source means including an antenna disposed along said rear wall at a location substantially midway between sAid side walls and spaced from said top wall a distance approximately equal to one-fourth of the height of said heating cavity.
Claim 20
Dependent Claim
78 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is lambda , and said heating cavity has a width of 1.12 lambda and a height of 0.645 lambda and a depth of 1.12 lambda , said source means including an antenna disposed along said rear wall at a location substantially midway between said side walls and spaced from said top wall a distance approximately equal to one-fourth of the height of said heating cavity.
Claim 21
Dependent Claim
19 words
The electronic heating apparatus set forth in claim 9, wherein said predetermined wavelength is substantially equal to 12.9 inches.
Claim 22
Dependent Claim
191 words
Electronic heating apparatus comprising a metal enclosure in the form of a rectangular parallelepiped including a top wall, a bottom wall, a front wall, a rear wall and two opposed side walls defining a heating cavity for receiving therein a body to be heated, source means electrically coupled to said heating cavity at a location along said rear wall in the upper half thereof, said source means transmitting microwave energy of a predetermined wavelength into said heating cavity for exciting therein two predetermined complementary electromagnetic field modes, at least one of said predetermined electromagnetic field modes having the fields thereof constant in a direction parallel to one of the dimensions of said heating cavity, each of said predetermined electromagnetic field modes having the fields thereof varying in the direction in which the fields of the other mode are constant, and tuning means disposed in said heating cavity and coupled to said top wall for coupling electromagnetic field modes other than said predetermined complementary modes and tuning said other modes off resonance, whereby there is established in said heating cavity an undistorted electromagnetic field pattern providing uniform heating of an associated body.
Claim 23
Dependent Claim
191 words
Electronic heating apparatus comprising a metal enclosure in the form of a rectangular parallelepiped including a top wall, a bottom wall, a front wall, a rear wall and two opposed side walls defining a heating cavity for receiving therein a body to be heated, source means electrically coupled to said heating cavity at a location along said rear wall in the upper half thereof, said source means transmitting microwave energy of a predetermined wavelength into said heating cavity for exciting therein two predetermined complementary electromagnetic field modes, at least one of said predetermined electromagnetic field modes having the fields thereof constant in a direction parallel to one of the dimensions of said heating cavity, each of said predetermined electromagnetic field modes having the fields thereof varying in the direction in which the fields of the other mode are constant, and tuning means disposed in said heating cavity and coupled to said top wall for coupling electromagnetic field modes other than said predetermined complementary modes and tuning said other modes off resonance, whereby there is established in said heating cavity an undistorted electromagnetic field pattern providing uniform heating of an associated body.
Claim 24
Dependent Claim
59 words
The electronic heating apparatus set forth in claim 20, wherein said source means includes an antenna disposed along said rear wall at a location substantially midway between said side walls and spaced from said top wall a distance approximately equal to one-fourth of the height of said heating cavity, said tuning means being disposed centrally of said top wall.
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) | 1977-12-16 | 1978-06-17 | 1978-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-16 | 1982-06-17 | 1982-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-16 | 1986-06-17 | 1986-12-17 | $7700.00 | Window Closed / Lapsed |