Patent US4851631A successfully refreshed from Google Patents.
US4851631A
Expired / Lapsed
US
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Food container for microwave heating and method of substantially eliminating arching in a microwave food container
Assignee: General Mills Marketing Inc
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Filing: 1986-10-23
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Granted: 1989-07-25
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Expires: 2006-10-23
Abstract
Abstract A food container for use in a microwave oven is disclosed. The container contains a plurality of food substances, and employs a metal shield to shield at least one of the food substances from microwave radiation. Arcing and other problems associated with the use of metal shielding are avoided by proper selection of the geometry of the metal shield. The metal shield is preferably looped in a manner which provides some electrical inductance, and the ends of the metal shield are overlapped and separated by a dielectric material to provide some electrical capacitance. The geometry of the shield is selected so that the inductance and the capacitance in effect form a "tuned circuit" which minimizes problems associated with resonance and which eliminates arcing.
Inventors
- 👤 Dan J. Wendt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:27
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; B; B65; B65D; B65D81/00; B65D81/34; B65D81/3446; B65D81/3453; B65D2581/00; B65D2581/34; B65D2581/3401; B65D2581/3429; B65D2581/3431; B65D2581/3437; B65D2581/3439; B65D2581/344; B65D2581/3441; B65D2581/3471; B65D2581/3472; B65D2581/3486; B65D2581/3489; Y; Y10; Y10S; Y10S99/00; Y10S99/14
Claims Analysis
Total Claims: 201
Claim 1
Independent Claim
211 words
A package for differential heating of food material in a microwave environment employing a shield having a geometry selected to avoid arcing, comprising: a generally cylindrical container containing a food material to be heated by microwaves and having at least a portion of the food material which is to be shielded from microwaves; a conductive shield, the shield being wrapped around a portion of the generally cylindrical container near where the portion of the food material to be shielded is located, the shield having a circumference and a height, the shield having non-resonant dimensions to avoid arcing where the height and circumference are selected such that: ##EQU37## where λ s is the resonant wavelength of the microwaves in the shield, h is the height of the shield, C is the circumference of the shield, and N and M are each integers, for example, 0, 1, 2, 3, 4, etc.; whereby resonance of the shield and resonant voltages at the edges of the shield are avoided to minimize arcing when the shield is exposed to the microwaves; and, the shield being operative to allow the food material to be heated by microwaves while substantially reducing the exposure of the shielded portion of the food material to the heating effects of the microwaves.
Claim 2
Dependent Claim
211 words
A package for differential heating of food material in a microwave environment employing a shield having a geometry selected to avoid arcing, comprising: a generally cylindrical container containing a food material to be heated by microwaves and having at least a portion of the food material which is to be shielded from microwaves; a conductive shield, the shield being wrapped around a portion of the generally cylindrical container near where the portion of the food material to be shielded is located, the shield having a circumference and a height, the shield having non-resonant dimensions to avoid arcing where the height and circumference are selected such that: ##EQU37## where λ s is the resonant wavelength of the microwaves in the shield, h is the height of the shield, C is the circumference of the shield, and N and M are each integers, for example, 0, 1, 2, 3, 4, etc.; whereby resonance of the shield and resonant voltages at the edges of the shield are avoided to minimize arcing when the shield is exposed to the microwaves; and, the shield being operative to allow the food material to be heated by microwaves while substantially reducing the exposure of the shielded portion of the food material to the heating effects of the microwaves.
Claim 3
Dependent Claim
32 words
The package according to claim I, further comprising: a conductive top covering the cylindrical container on an end of the cylindrical container near the portion of the food material to be shielded.
Claim 4
Dependent Claim
37 words
The package according to claim 2, wherein the conductive top has diameter, the top being selected so that the diameter of the top is not equal to any integer multiple of the half wavelength of the microwaves.
Claim 5
Dependent Claim
55 words
The package according to claim 1, wherein: the height "h" of the shield and the circumference "C" of the shield are selected so that: ##EQU38## is not equal to plus or minus 10 percent of: ##EQU39## for all integer values of N and M, whereby resonance of the shield is substantially avoided to minimize arcing.
Claim 6
Dependent Claim
55 words
The package according to claim 1, wherein: the height "h" of the shield and the circumference "C" of the shield are selected so that: ##EQU40## is not equal to plus or minus 20 percent of: ##EQU41## for all integer values of N and M, whereby resonance of the shield is substantially avoided to minimize arcing.
Claim 7
Dependent Claim
15 words
The package according to claim 5, wherein: λ s is equal to about 4.2 inches.
Claim 8
Dependent Claim
36 words
The package according to claim 1, wherein: the height "h" of the shield and the circumference "C" of the shield are selected so that: ##EQU42## is not equal to plus or minus 30 percent of: ##EQU43##
Claim 9
Dependent Claim
28 words
The package according to claim 1, wherein: ##EQU44## is not equal to any number in the range 0.125 to 0.238, where "h" and "C" are expressed in inches.
Claim 10
Dependent Claim
28 words
The package according to claim 1, wherein: ##EQU45## is not equal to any number in the range 0.204 to 0.249, where "h" and "C" are expressed in inches.
Claim 11
Dependent Claim
28 words
The package according to claim 1, wherein: ##EQU46## is not equal to any number in the range 0.181 to 0.272, where "h" and "C" are expressed in inches.
Claim 12
Dependent Claim
28 words
The package according to claim 1, wherein: ##EQU47## is not equal to any number in the range 0.159 to 0.295, where "h" and "C" are expressed in inches.
Claim 13
Independent Claim
171 words
A method of producing a non-arcing shielded container for differential heating of food material with microwave radiation where the shield has a geometery selected to avoid resonance, comprising the steps of: providing a container for food having a first food material to be heated by microwave radiation and a second food material to be shielded from the heating effects of microwave radiation; selecting a conductive shield so that the shield has a height which is not equal to any multiple of a half wavelength of the microwave radiation, and the shield has a circumference which is not equal to any multiple of a half wavelength of the microwave radiation, thereby avoiding resonance of the shield at the frequency of the microwave radiation to minimize arcing; and providing the shield around the container in microwave shielding relationship to the second food material to be shielded to reduce the heating effect of the microwave radiation by substantially shielding the second food material and permitting differential heating of the food material in the container.
Claim 14
Independent Claim
171 words
A method of producing a non-arcing shielded container for differential heating of food material with microwave radiation where the shield has a geometery selected to avoid resonance, comprising the steps of: providing a container for food having a first food material to be heated by microwave radiation and a second food material to be shielded from the heating effects of microwave radiation; selecting a conductive shield so that the shield has a height which is not equal to any multiple of a half wavelength of the microwave radiation, and the shield has a circumference which is not equal to any multiple of a half wavelength of the microwave radiation, thereby avoiding resonance of the shield at the frequency of the microwave radiation to minimize arcing; and providing the shield around the container in microwave shielding relationship to the second food material to be shielded to reduce the heating effect of the microwave radiation by substantially shielding the second food material and permitting differential heating of the food material in the container.
Claim 15
Independent Claim
252 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; forming a conductive shield around a portion of the food container, the conductive shield being located in microwave shielding relationship to the second food material, the conductive shield being generally cylindrically shaped, the conductive shield having a first end and a second end; overlapping the first end of the shield over the second end of the shield to form an overlapped shield, where the first and second ends of the overlapped shield are separated by a dielectric material, the amount of the overlap being selected to damp potential arcing currents, where the relative arcing potential is defined by: ##EQU48## where D is the diameter of the cylindrically-shaped shield, h is the height of the shield, L is the distance that the first end of the shield overlaps the second end of the shield, K is the dielectric constant of the dielectric material between the first and second ends of the shield, d is the distance that the first and second ends of the shield are spaced apart, λ 0 is the wavelength of the microwave radiation; and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 16
Independent Claim
252 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; forming a conductive shield around a portion of the food container, the conductive shield being located in microwave shielding relationship to the second food material, the conductive shield being generally cylindrically shaped, the conductive shield having a first end and a second end; overlapping the first end of the shield over the second end of the shield to form an overlapped shield, where the first and second ends of the overlapped shield are separated by a dielectric material, the amount of the overlap being selected to damp potential arcing currents, where the relative arcing potential is defined by: ##EQU48## where D is the diameter of the cylindrically-shaped shield, h is the height of the shield, L is the distance that the first end of the shield overlaps the second end of the shield, K is the dielectric constant of the dielectric material between the first and second ends of the shield, d is the distance that the first and second ends of the shield are spaced apart, λ 0 is the wavelength of the microwave radiation; and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 17
Dependent Claim
35 words
The method according to claim 13, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.8.
Claim 18
Dependent Claim
35 words
The method according to claim 13, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.7.
Claim 19
Dependent Claim
71 words
The method according to claim 15, wherein: the height "h" of the shield and the diameter "D" of the shield are selected so that: ##EQU49## is not equal to plus or minus 5 percent of: ##EQU50## for all integer values of "N" and "M", where "λ s " is the resonant wavelength of microwave frequency currents in the shield, whereby resonance of the overlapped shield is substantially avoided to minimize arcing.
Claim 20
Dependent Claim
28 words
The method according to claim 16, wherein: the height "h" of the shield is selected to be in the range of about 2.5 inches to about 3.5 inches.
Claim 21
Dependent Claim
28 words
The method according to claim 17, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 22
Dependent Claim
43 words
The method according to claim 18, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 23
Dependent Claim
43 words
The method according to claim 17, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 24
Dependent Claim
28 words
The method according to claim 16, wherein: the height "h" of the shield is selected to be in the range of about 2.4 inches to about 3.6 inches.
Claim 25
Dependent Claim
28 words
The method according to claim 21, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 26
Dependent Claim
43 words
The method according to claim 21, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 27
Dependent Claim
28 words
The method according to claim 16, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 28
Dependent Claim
43 words
The method according to claim 24, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 29
Dependent Claim
43 words
The method according to claim 16, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 30
Dependent Claim
35 words
The method according to claim 13, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.6.
Claim 31
Dependent Claim
71 words
The method according to claim 27, wherein: the height "h" of the shield and the diameter "D" of the shield are selected so that: ##EQU51## is not equal to plus or minus 10 percent of: ##EQU52## for all integer values of "N" and "M", where "λ s " is the resonant wavelength of microwave frequency currents in the shield, whereby resonance of the overlapped shield is substantially avoided to minimize arcing.
Claim 32
Dependent Claim
28 words
The method according to claim 28, wherein: the height "h" of the shield is selected to be in the range of about 2.5 inches to about 3.5 inches.
Claim 33
Dependent Claim
28 words
The method according to claim 29, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 34
Dependent Claim
43 words
The method according to claim 29, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 35
Dependent Claim
28 words
The method according to claim 28, wherein: the height "h" of the shield is selected to be in the range of about 2.4 inches to about 3.6 inches.
Claim 36
Dependent Claim
28 words
The method according to claim 32, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 37
Dependent Claim
43 words
The method according to claim 32, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 38
Dependent Claim
28 words
The method according to claim 28, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 39
Dependent Claim
43 words
The method according to claim 35, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 40
Dependent Claim
43 words
The method according to claim 28, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 41
Dependent Claim
44 words
The method according to claim 13, wherein: the height "h" of the shield and diameter "D" of the shield are selected so that: ##EQU53## is not equal to any number in the range 0.204 to 0.249, where "h" and "D" are expressed in inches.
Claim 42
Dependent Claim
28 words
The method according to claim 38, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 43
Dependent Claim
43 words
The method according to claim 38, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 44
Dependent Claim
44 words
The method according to claim 13, wherein: the height "h" of the shield and diameter "D" of the shield are selected so that: ##EQU54## is not equal to any number in the range 0.181 to 0.272, where "h" and "D" are expressed in inches.
Claim 45
Dependent Claim
28 words
The method according to claim 41, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 46
Dependent Claim
43 words
The method according to claim 41, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 47
Dependent Claim
44 words
The method according to claim 13, wherein: the height "h" of the shield and diameter "D" of the shield are selected so that: ##EQU55## is not equal to any number in the range 0.159 to 0.295, where "h" and "D" are expressed in inches.
Claim 48
Dependent Claim
28 words
The method according to claim 44, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 49
Dependent Claim
43 words
The method according to claim 45, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 50
Dependent Claim
43 words
The method according to claim 44, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 51
Dependent Claim
35 words
The method according to claim 13, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.5.
Claim 52
Dependent Claim
71 words
The method according to claim 48, wherein: the height "h" of the shield and the diameter "D" of the shield are selected so that: ##EQU56## is not equal to plus or minus 20 percent of: ##EQU57## for all integer values of "N" and "M", where "λ s " is the resonant wavelength of microwave frequency currents in the shield, whereby resonance of the overlapped shield is substantially avoided to minimize arcing.
Claim 53
Dependent Claim
28 words
The method according to claim 49, wherein: the height "h" of the shield is selected to be in the range of about 2.5 inches to about 3.5 inches.
Claim 54
Dependent Claim
28 words
The method according to claim 50, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 55
Dependent Claim
43 words
The method according to claim 50, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 56
Dependent Claim
28 words
The method according to claim 49 wherein: the height "h" of the shield is selected to be in the range of about 2.4 inches to about 3.6 inches.
Claim 57
Dependent Claim
28 words
The method according to claim 53, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 58
Dependent Claim
43 words
The method according to claim 53, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 59
Dependent Claim
28 words
The method according to claim 49, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 60
Dependent Claim
43 words
The method according to claim 56, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 61
Dependent Claim
43 words
The method according to claim 49, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 62
Dependent Claim
35 words
The method according to claim 13, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.4.
Claim 63
Dependent Claim
35 words
The method according to claim 13, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.3.
Claim 64
Dependent Claim
35 words
The method according to claim 13, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.2.
Claim 65
Dependent Claim
35 words
The method according to claim 13, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.1.
Claim 66
Dependent Claim
77 words
The method according to claim 13, further comprising the step of: providing a conductive top to seal the food container, the conductive top being in microwave shielding relationship with the shield, the conductive top having a diameter "d T ", the diameter of the top being selected so that: ##EQU58## is not equal to ##EQU59## for all integer values of "N" and "M", where "λ T " is the resonant wavelength of microwaves in the conductive top.
Claim 67
Dependent Claim
36 words
The method according to claim 63, further comprising the step of: recessing the conductive top into the container, so that edges of the conductive top are located remote from the second food material to be shielded.
Claim 68
Dependent Claim
71 words
The method according to claim 13, wherein: the height "h" of the shield and the diameter "D" of the shield are selected so that: ##EQU60## is not equal to plus or minus 30 percent of: ##EQU61## for all integer values of "N" and "M", where "λ s " is the resonant wavelength of microwave frequency currents in the shield, whereby resonance of the overlapped shield is substantially avoided to minimize arcing.
Claim 69
Dependent Claim
28 words
The method according to claim 65, wherein: the height "h" of the shield is selected to be in the range of about 2.5 inches to about 3.5 inches.
Claim 70
Dependent Claim
28 words
The method according to claim 66, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 71
Dependent Claim
43 words
The method according to claim 66, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 72
Dependent Claim
28 words
The method according to claim 65, wherein: the height "h" of the shield is selected to be in the range of about 2.4 inches to about 3.6 inches.
Claim 73
Dependent Claim
28 words
The method according to claim 69, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 74
Dependent Claim
43 words
The method according to claim 70, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 75
Dependent Claim
43 words
The method according to claim 69, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 76
Dependent Claim
28 words
The method according to claim 65, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 77
Dependent Claim
43 words
The method according to claim 73, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 78
Dependent Claim
43 words
The method according to claim 65, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 79
Dependent Claim
44 words
The method according to claim 13, wherein: the height "h" of the shield and diameter "D" of the shield are selected so that: ##EQU62## is not equal to any number in the range 0.215 to 0.238, where "h" and "D" are expressed in inches.
Claim 80
Dependent Claim
28 words
The method according to claim 76, wherein: the diameter "D" of the shield is selected to be in the range of about 2.8 inches to about 3.6 inches.
Claim 81
Dependent Claim
43 words
The method according to claim 77, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 82
Dependent Claim
43 words
The method according to claim 76, wherein: the second food material to be at least partially shielded from microwave radiation is selected to have a thickness of about 43 millimeters to about 54 millimeters to avoid resonant fields in the second food material.
Claim 83
Independent Claim
234 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; providing a conductive shield shielding a portion of the food container, the shield generally being formed into an electrical loop, the shield having a first end and a second end; overlapping the first end of the shield over the second end of the shield, where the first and second ends of the shield are separated by a dielectric material, the amount of the overlap being sufficient to damp potential arcing currents, where the relative arcing potential is defined by: ##EQU63## where D is the diameter of the electrically looped shield, h is the height of the shield, L is the distance that the first end of the shield overlaps the second end of the shield, K is the dielectric constant of the dielectric material between the first and second ends of the shield, d is the distance that the first and second ends of the shield are spaced apart, λ 0 is the wavelength of the microwave radiation; and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 84
Independent Claim
234 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; providing a conductive shield shielding a portion of the food container, the shield generally being formed into an electrical loop, the shield having a first end and a second end; overlapping the first end of the shield over the second end of the shield, where the first and second ends of the shield are separated by a dielectric material, the amount of the overlap being sufficient to damp potential arcing currents, where the relative arcing potential is defined by: ##EQU63## where D is the diameter of the electrically looped shield, h is the height of the shield, L is the distance that the first end of the shield overlaps the second end of the shield, K is the dielectric constant of the dielectric material between the first and second ends of the shield, d is the distance that the first and second ends of the shield are spaced apart, λ 0 is the wavelength of the microwave radiation; and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 85
Dependent Claim
32 words
The method according to claim 80, further comprising the step of: sealing the food container with a conductive top, the conductive top being provided in microwave shielding relationship to the conductive shield.
Claim 86
Dependent Claim
55 words
The method according to claim 81, further comprising the step of: recessing the conductive top in the food container so that edges of the top are located remote from the second food material, whereby the heating effect of fields induced in the edges of the conductive top upon the second food material will be minimized.
Claim 87
Dependent Claim
35 words
The method according to claim 82, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.2.
Claim 88
Dependent Claim
57 words
The method according to claim 81, further comprising the step of: selecting dimensions for the conductive top, where the top has a diameter "d T ", such that: ##EQU64## is not equal to ##EQU65## for all integer values of "N" and "M", where "λ T " is the acutal resonant wavelength of microwaves in the conductive top.
Claim 89
Dependent Claim
35 words
The method according to claim 81, wherein the step of reducing the relative arcing potential is sufficent to produce a value for the relative arcing potential in the range of about 0 to about 0.8.
Claim 90
Dependent Claim
33 words
The method according to claim 81, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 0.7.
Claim 91
Dependent Claim
34 words
The method according to claim 81, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to 0.6.
Claim 92
Dependent Claim
35 words
The method according to claim 81, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.5.
Claim 93
Dependent Claim
35 words
The method according to claim 81, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.4.
Claim 94
Dependent Claim
35 words
The method according to claim 81, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.3.
Claim 95
Dependent Claim
35 words
The method according to claim 81, wherein the step of reducing the relative arcing potential is sufficent to produce a value for the relative arcing potential in the range of about 0 to about 0.1.
Claim 96
Dependent Claim
267 words
A non-arcing package for the differential heating of food with microwave radiation where potential arcing currents are damped by a shield having a nonresonant combination of capacitance and inductance, comprising: a microwave food container, the food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; a conductive shield shielding a portion of the food container in proximity to the second food material to be at least partially shielded, the shield being generally electrically looped, the shield having some inductance, the shield having a first end, the shield having a second end which overlaps the first end for a distance "L", the first end and the second end being spaced apart a distance "d", the first end and the second end being separated by a dielectric material having a dielectric constant of "K", the shield having some capacitance, the looped shield having a diameter of "D" and a height of "h"; and, the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield being selected to damp potential arcing currents by reducing the relative arcing potential defined by: ##EQU66## where λ 0 is the wavelength of the microwave radiation; and, whereby the shield is provided with a nonresonant combination of capacitance and inductance to damp potential arcing currents thereby substantially avoiding arcing.
Claim 97
Dependent Claim
267 words
A non-arcing package for the differential heating of food with microwave radiation where potential arcing currents are damped by a shield having a nonresonant combination of capacitance and inductance, comprising: a microwave food container, the food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; a conductive shield shielding a portion of the food container in proximity to the second food material to be at least partially shielded, the shield being generally electrically looped, the shield having some inductance, the shield having a first end, the shield having a second end which overlaps the first end for a distance "L", the first end and the second end being spaced apart a distance "d", the first end and the second end being separated by a dielectric material having a dielectric constant of "K", the shield having some capacitance, the looped shield having a diameter of "D" and a height of "h"; and, the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield being selected to damp potential arcing currents by reducing the relative arcing potential defined by: ##EQU66## where λ 0 is the wavelength of the microwave radiation; and, whereby the shield is provided with a nonresonant combination of capacitance and inductance to damp potential arcing currents thereby substantially avoiding arcing.
Claim 98
Dependent Claim
76 words
The package according to claim 92, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential in the range of about 0 to about 0.8.
Claim 99
Dependent Claim
76 words
The package according to claim 92, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential in the range of about 0 to about 0.7.
Claim 100
Dependent Claim
22 words
The package according to claim 94, wherein: the diameter "D" of the shield is between about 2.8 inches and about 3.6 inches.
Claim 101
Dependent Claim
22 words
The package according to claim 95, wherein: the height "h" of the shield is between about 2.4 inches and about 3.6 inches.
Claim 102
Dependent Claim
30 words
The package according to claim 95, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.05 inches and about 1.5 inches.
Claim 103
Dependent Claim
30 words
The package according to claim 95, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.1 inches and about 1.5 inches.
Claim 104
Dependent Claim
30 words
The package according to claim 95, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.5 inches and about 1.5 inches.
Claim 105
Dependent Claim
22 words
The package according to claim 94, wherein: the diameter "D" of the shield is between about 2.9 inches and about 3.4 inches.
Claim 106
Dependent Claim
22 words
The package according to claim 100, wherein: the height "h" of the shield is between about 2.6 inches and about 3.4 inches.
Claim 107
Dependent Claim
22 words
The package according to claim 94, wherein: the diameter "D" of the shield is between about 3.0 inches and about 3.2 inches.
Claim 108
Dependent Claim
22 words
The package according to claim 102, wherein: the height "h" of the shield is between about 2.8 inches and about 3.2 inches.
Claim 109
Dependent Claim
30 words
The package according to claim 103, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.05 inches and about 1.5 inches.
Claim 110
Dependent Claim
30 words
The package according to claim 103, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.1 inches and about 1.5 inches.
Claim 111
Dependent Claim
30 words
The package according to claim 103, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.5 inches and about 1.5 inches.
Claim 112
Dependent Claim
22 words
The package according to claim 94, wherein: the height "h" of the shield is between about 2.4 inches and about 3.6 inches.
Claim 113
Dependent Claim
30 words
The package according to claim 107, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.05 inches and about 1.5 inches.
Claim 114
Dependent Claim
30 words
The package according to claim 107, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.1 inches and about 1.5 inches.
Claim 115
Dependent Claim
30 words
The package according to claim 107, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.5 inches and about 1.5 inches.
Claim 116
Dependent Claim
22 words
The package according to claim 94, wherein: the height "h" of the shield is between about 2.6 inches and about 3.4 inches.
Claim 117
Dependent Claim
22 words
The package according to claim 94, wherein: the height "h" of the shield is between aobut 2.8 inches and about 3.2 inches.
Claim 118
Dependent Claim
30 words
The package according to claim 94, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.05 inches and about 1.5 inches.
Claim 119
Dependent Claim
30 words
The package according to claim 94, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.1 inches and about 1.5 inches.
Claim 120
Dependent Claim
30 words
The package according to claim 94, wherein: the amount of overlap "L" between the first and second ends of the shield is between about 0.5 inches and about 1.5 inches.
Claim 121
Dependent Claim
76 words
The package according to claim 92, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential in the range of about 0 to about 0.6.
Claim 122
Dependent Claim
76 words
The package according to claim 92, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential in the range of about 0 to about 0.5.
Claim 123
Dependent Claim
76 words
The package according to claim 92, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential in the range of about 0 to about 0.4.
Claim 124
Dependent Claim
76 words
The package according to claim 92, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential in the range of about 0 to about 0.3.
Claim 125
Dependent Claim
76 words
The package according to claim 92, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential in the range of about 0 to about 0.2.
Claim 126
Dependent Claim
76 words
The package according to claim 92, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential in the range of about 0 to about 0.1.
Claim 127
Independent Claim
167 words
A method of producing a non-arcing shielded container for differential heating of food material with microwave radiation where the shield has dimensions selected to avoid arcing, comprising the steps of: providing a container for food having a first food material to be heated by microwave radiation and a second food material to be shielded from the heating effects of microwave radiation; selecting a conducting shield so that the shield has a height which is not equal to any integer multiple of from about 5.4 centimeters to about 6.9 centimeters, and the shield has a circumference which is not equal to any integer multiple of from about 5.4 centimeters to about 6.9 centimeters, thereby avoiding resonance of the shield at the frequency of the microwave radiation to minimize arcing; and providing the shield around the second food material to be shielded to reduce the heating effect of the microwave radiation by substantially shielding the second food material and permitting differential heating of the food material in the container.
Claim 128
Independent Claim
167 words
A method of producing a non-arcing shielded container for differential heating of food material with microwave radiation where the shield has dimensions selected to avoid arcing, comprising the steps of: providing a container for food having a first food material to be heated by microwave radiation and a second food material to be shielded from the heating effects of microwave radiation; selecting a conducting shield so that the shield has a height which is not equal to any integer multiple of from about 5.4 centimeters to about 6.9 centimeters, and the shield has a circumference which is not equal to any integer multiple of from about 5.4 centimeters to about 6.9 centimeters, thereby avoiding resonance of the shield at the frequency of the microwave radiation to minimize arcing; and providing the shield around the second food material to be shielded to reduce the heating effect of the microwave radiation by substantially shielding the second food material and permitting differential heating of the food material in the container.
Claim 129
Dependent Claim
204 words
A package for differential heating of food material in a microwave environment employing a shield having a shape selected to avoid arcing, comprising: a container containing a first food material to be heated by microwaves and a second food material to be shielded from microwaves; a conductive shield, the shield being formed around the second food material to be shielded, the shield having a shape that is generally cylindrical, the shield having a circumference "C" and a height "h", the shield having non-resonant dimensions to avoid arcing where the height "h" and circumference "C" are selected such that: ##EQU67## is not equal to any number in the range from about 0.159 to about 0.295 where "h" is the height of the shield in inches, "C" is the circumference of the shield in inches and"N" and "M" are each interegers, for example, 0, 1, 2, 3, 4, etc.; whereby resonance of the shield and resonant voltages on the shield are avoided to minimize arcing when the shield is exposed to the microwaves; and, the shield being operative to allow the first food material to be heated by microwaves while substantially reducing the exposure of the second food material to the heating effects of the microwaves.
Claim 130
Dependent Claim
204 words
A package for differential heating of food material in a microwave environment employing a shield having a shape selected to avoid arcing, comprising: a container containing a first food material to be heated by microwaves and a second food material to be shielded from microwaves; a conductive shield, the shield being formed around the second food material to be shielded, the shield having a shape that is generally cylindrical, the shield having a circumference "C" and a height "h", the shield having non-resonant dimensions to avoid arcing where the height "h" and circumference "C" are selected such that: ##EQU67## is not equal to any number in the range from about 0.159 to about 0.295 where "h" is the height of the shield in inches, "C" is the circumference of the shield in inches and"N" and "M" are each interegers, for example, 0, 1, 2, 3, 4, etc.; whereby resonance of the shield and resonant voltages on the shield are avoided to minimize arcing when the shield is exposed to the microwaves; and, the shield being operative to allow the first food material to be heated by microwaves while substantially reducing the exposure of the second food material to the heating effects of the microwaves.
Claim 131
Dependent Claim
28 words
The package accordin to claim 123, further comprising: a conductive top covering the container on an end of the container near the second food material to be shielded.
Claim 132
Dependent Claim
54 words
The package according to claim 124, wherein the conductive top is circular and has a diameter, the top being selected so that the diameter of the top is not equal to about 2.1 inches, or about 2.95 inches, or about 4.2 inches, or about 4.7 inches, or about 5.9 inches or about 6.3 inches.
Claim 133
Dependent Claim
65 words
The package according to claim 124, wherein: the conductive top has a diameter "d T ", the diameter "d T " of the conductive top is selected so that: ##EQU68## is not equal to ##EQU69## where "N" and "M" are integers, for example, 0, 1, 2, 3, 4, etc., and "λ T " is the actual resonant wavelength of the microwaves in the conductive top.
Claim 134
Independent Claim
232 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a microwave food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; providing a conductive shield around the second food material to be shielded, the shield generally having a cylindrical shape, the shield having a first end and a second end; overlapping the first end of the shield over the second end of the shield, where the first and second ends of the shield are separated by a dielectric material, the amount of the overlap being selected to damp potential arcing currents, where the relative arcing potential is defined by: ##EQU70## where D is the diameter of the cylindricallyshaped field in inches, h is the height of the shield in inches, L is the distance that the first end of the shield overlaps the second end of the shield in inches, K is the dielectric constant of the dielectric material between the first and second ends of the shield, d is the distance that the first and second ends of the shield are spaced apart in inches, and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 135
Independent Claim
232 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a microwave food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; providing a conductive shield around the second food material to be shielded, the shield generally having a cylindrical shape, the shield having a first end and a second end; overlapping the first end of the shield over the second end of the shield, where the first and second ends of the shield are separated by a dielectric material, the amount of the overlap being selected to damp potential arcing currents, where the relative arcing potential is defined by: ##EQU70## where D is the diameter of the cylindricallyshaped field in inches, h is the height of the shield in inches, L is the distance that the first end of the shield overlaps the second end of the shield in inches, K is the dielectric constant of the dielectric material between the first and second ends of the shield, d is the distance that the first and second ends of the shield are spaced apart in inches, and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 136
Dependent Claim
35 words
The method according to claim 127, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.8.
Claim 137
Dependent Claim
35 words
The method according to claim 127, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.7.
Claim 138
Dependent Claim
35 words
The method according to claim 127, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.6.
Claim 139
Dependent Claim
35 words
The method according to claim 127, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.5.
Claim 140
Dependent Claim
35 words
The method according to claim 127, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.4.
Claim 141
Dependent Claim
35 words
The method according to claim 127, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.3.
Claim 142
Dependent Claim
35 words
The method according to claim 127, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.2.
Claim 143
Dependent Claim
35 words
The method according to claim 127, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.1.
Claim 144
Dependent Claim
231 words
A non-arcing package for the differential heating of food with microwave radiation where potential arcing currents are damped by a shield having a nonresonant combination of capacitance and inductance, comprising: a food container, the food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; a conductive shield around the second food material to be at least partially shielded, the shield generally being formed into a loop having inductance, the shield having a first end, the shield having a second end which overlaps the first end for a distance "L", the first end and the second end being spaced apart a distance "d", the first end and the second end being separated by a dielectric material having a dielectric constant of "K", the shield generally having capacitance, the looped shield having a diameter of "D" and a height of "h"; and, the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield being selected to form a combination of inductance and capacitance to damp potential arcing currents by reducing the relative arcing potential defined by: ##EQU71##
Claim 145
Dependent Claim
231 words
A non-arcing package for the differential heating of food with microwave radiation where potential arcing currents are damped by a shield having a nonresonant combination of capacitance and inductance, comprising: a food container, the food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; a conductive shield around the second food material to be at least partially shielded, the shield generally being formed into a loop having inductance, the shield having a first end, the shield having a second end which overlaps the first end for a distance "L", the first end and the second end being spaced apart a distance "d", the first end and the second end being separated by a dielectric material having a dielectric constant of "K", the shield generally having capacitance, the looped shield having a diameter of "D" and a height of "h"; and, the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield being selected to form a combination of inductance and capacitance to damp potential arcing currents by reducing the relative arcing potential defined by: ##EQU71##
Claim 146
Dependent Claim
77 words
The package according to claim 136, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the relative arcing potential in the range of about 0 to about 0.8.
Claim 147
Dependent Claim
77 words
The package according to claim 136, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the relative arcing potential in the range of about 0 to about 0.7.
Claim 148
Dependent Claim
77 words
The package according to claim 136, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the relative arcing potential in the range of about 0 to about 0.6.
Claim 149
Dependent Claim
77 words
The package according to claim 136, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the relative arcing potential in the range of about 0 to about 0.5.
Claim 150
Dependent Claim
86 words
The package according to claim 136, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the relative arcing potential in the range of about 0 to about 0.4.
Claim 151
Dependent Claim
77 words
The package according to claim 136, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the relative arcing potential in the range of about 0 to about 0.3.
Claim 152
Dependent Claim
77 words
The package according to claim 136, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the relative arcing potential in the range of about 0 to about 0.2.
Claim 153
Dependent Claim
77 words
The package according to claim 136, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the relative arcing potential in the range of about 0 to about 0.1.
Claim 154
Independent Claim
93 words
A method of heating food material in a microwave environment, comprising the steps of: constructing a food package having a conductive shield at least partially including a portion of microwave radiation upon a portion of food material in the food package, the conductive shield having overlapping conductive ends separated by a dielectric material; selecting the conductive shield so that none of the dimensions of the shield are resonant at the frequency of the microwave radiation; and, irradiating the food package with microwave radiation to differentially heat the food material in the food package.
Claim 155
Independent Claim
93 words
A method of heating food material in a microwave environment, comprising the steps of: constructing a food package having a conductive shield at least partially including a portion of microwave radiation upon a portion of food material in the food package, the conductive shield having overlapping conductive ends separated by a dielectric material; selecting the conductive shield so that none of the dimensions of the shield are resonant at the frequency of the microwave radiation; and, irradiating the food package with microwave radiation to differentially heat the food material in the food package.
Claim 156
Dependent Claim
246 words
A package for differential heating of food material in a microwave environment employing a shield having a geometry selected to avoid arcing, comprising: a frustoconical container containing a first food material to be heated by microwaves and a second food material to be shielded from microwaves; a conductive shield, the shield being formed around a portion of the frustoconical container near where the second food material to be shielded is located, the shield having a minimum circumference and a maximum circumference, the shield having a height, the shield having nonresonant dimensions to avoid arcing where the height and circumference are selected such that: ##EQU72## for any circumference "C" within the range of circumferences between the minimum circumference and the maximum circumference; where "λ s " is the resonant wavelength of the microwave frequency currents in the shield, "h" is the height of the shield, "C" is the circumference of the shield, and ranges from the minimum circumference of the shield to the maximum circumference of the shield, and "N" and "M" are each integers, for example, 0, 1, 2, 3, 4, etc.; whereby resonance of the shield and resonant voltages at the edges of the shield are avoided to minimize arcing and effects of retransmitted fields when the shield is exposed to microwaves; and, the shield being operative to allow the first food material to be heated by microwaves while substantially reducing the exposure of the second food material to the heating effects of the microwaves.
Claim 157
Dependent Claim
246 words
A package for differential heating of food material in a microwave environment employing a shield having a geometry selected to avoid arcing, comprising: a frustoconical container containing a first food material to be heated by microwaves and a second food material to be shielded from microwaves; a conductive shield, the shield being formed around a portion of the frustoconical container near where the second food material to be shielded is located, the shield having a minimum circumference and a maximum circumference, the shield having a height, the shield having nonresonant dimensions to avoid arcing where the height and circumference are selected such that: ##EQU72## for any circumference "C" within the range of circumferences between the minimum circumference and the maximum circumference; where "λ s " is the resonant wavelength of the microwave frequency currents in the shield, "h" is the height of the shield, "C" is the circumference of the shield, and ranges from the minimum circumference of the shield to the maximum circumference of the shield, and "N" and "M" are each integers, for example, 0, 1, 2, 3, 4, etc.; whereby resonance of the shield and resonant voltages at the edges of the shield are avoided to minimize arcing and effects of retransmitted fields when the shield is exposed to microwaves; and, the shield being operative to allow the first food material to be heated by microwaves while substantially reducing the exposure of the second food material to the heating effects of the microwaves.
Claim 158
Dependent Claim
30 words
The package according to claim 146, further comprising: a conductive top covering the frustoconical container on an end of the frustoconical container near the second food material to be shielded.
Claim 159
Dependent Claim
38 words
The package according to claim 147, wherein the conductive top has a diameter, the top being selected so that the diameter of the top is not equal to any integer multiple of the half wavelength of the microwaves.
Claim 160
Dependent Claim
70 words
The package according to claim 146, wherein: the height "h" of the shield and the range of circumferences "C" of the shield are selected so that: ##EQU73## is not equal to plus or minus 10 percent of: ##EQU74## for all integer values of N and M, or for any value "C" within the range of circumferences of the shield, whereby resonance of the shield is substantially avoided to minimize arcing.
Claim 161
Dependent Claim
70 words
The package according to claim 146, wherein: the height "h" of the shield and the range of circumferences "C" of the shield are selected so that: ##EQU75## is not equal to plus or minus 20 percent of: ##EQU76## for all integer values of N and M, or for any value "C" within the range of circumferences of the shield, whereby resonance of the shield is substantially avoided to minimize arcing.
Claim 162
Dependent Claim
70 words
The package according to claim 146, wherein the height "h" of the shield and the range of circumferences "C" of the shield are selected so that: ##EQU77## is not equal to plus or minus 30 percent of: ##EQU78## for all integer values of N and M, or for any value "C" within the range of circumferences of the shield, whereby resonance of the shield is substantially avoided to minimize arcing.
Claim 163
Dependent Claim
15 words
The package according to claim 146, wherein: λ s is equal to about 4.2 inches.
Claim 164
Dependent Claim
69 words
The package according to claim 146, wherein: a conductive top having a diameter "d T " is provided to seal the container, the diameter "d T " of the top being selected so that: ##EQU79## is not equal to ##EQU80## where "N" and "M" are integers, for example, 0,1, 2, 3, 4, etc., and "λ T " is the actual resonant wavelength of the microwaves in the conductive top.
Claim 165
Independent Claim
200 words
A method of producing a non-arcing shielded container for differential heating of food material with microwave radiation where the shield has a geometry selected to avoid arcing, comprising the steps of: providing a container for food having a first food material to be heated my microwave radiation and a second food material to shielded from the heating effects of microwave radiation; selecting a frustoconical conductive shield so that the shield has a height which not equal to any multiple of a half wavelength of the microwave radiation, and the shield has a range of circumferences, the shield not having a circumference equal to a multiple of a half wavelength of the microwave radiation over a portion of the height of the frustoconical shield corresponding to the location of the second food material, thereby avoiding resonance of the shield at the frequency of the microwave radiation at a location which would overheat the second food material; and providing the shield around the container in the proximity of the second food material to be shielded to reduce the heating effect of the microwave radiation by substantially shielding the second food material and permitting differential heating of the food material in the container.
Claim 166
Independent Claim
200 words
A method of producing a non-arcing shielded container for differential heating of food material with microwave radiation where the shield has a geometry selected to avoid arcing, comprising the steps of: providing a container for food having a first food material to be heated my microwave radiation and a second food material to shielded from the heating effects of microwave radiation; selecting a frustoconical conductive shield so that the shield has a height which not equal to any multiple of a half wavelength of the microwave radiation, and the shield has a range of circumferences, the shield not having a circumference equal to a multiple of a half wavelength of the microwave radiation over a portion of the height of the frustoconical shield corresponding to the location of the second food material, thereby avoiding resonance of the shield at the frequency of the microwave radiation at a location which would overheat the second food material; and providing the shield around the container in the proximity of the second food material to be shielded to reduce the heating effect of the microwave radiation by substantially shielding the second food material and permitting differential heating of the food material in the container.
Claim 167
Dependent Claim
46 words
The method according to claim 154, further comprising the step of: selecting a resonant diameter for the conductive shield over a portion of the height of the frustoconical shield corresponding to the location of the first food material to enhance heating of the first food material.
Claim 168
Dependent Claim
39 words
The method according to claim 155, wherein: the shield is selected so that the shield does not have a circumference equal to a multiple of a half wavelength of the microwave radiation over the entire height of the shield.
Claim 169
Independent Claim
231 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a generally frustoconical food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; shielding a portion of the food container with a generally frustoconical shaped conductive shield, the conductive shield having a first end and a second end; overlapping the first end of the shield over the second end of the shield, where the first and second ends of the shield are separated by a dielectric material, the amount of the overlap being selected to damp potential arcing currents, where the relative arcing potential is defined by: ##EQU81## where D is the mean diameter of the frustoconical-shaped shield, h is the height of the shield, L is the distance that the first end of the shield overlaps the second end of the shield, K is the dielectric constant of the dielectric material between the first and second ends of the shield, d is the distance that the first and second ends of the shield are spaced apart, λ 0 is the wavelength of the microwave radiation; and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 170
Independent Claim
231 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a generally frustoconical food container having a first food material to be heated by microwave radiation and a second food material to be at least partially shielded from microwave radiation; shielding a portion of the food container with a generally frustoconical shaped conductive shield, the conductive shield having a first end and a second end; overlapping the first end of the shield over the second end of the shield, where the first and second ends of the shield are separated by a dielectric material, the amount of the overlap being selected to damp potential arcing currents, where the relative arcing potential is defined by: ##EQU81## where D is the mean diameter of the frustoconical-shaped shield, h is the height of the shield, L is the distance that the first end of the shield overlaps the second end of the shield, K is the dielectric constant of the dielectric material between the first and second ends of the shield, d is the distance that the first and second ends of the shield are spaced apart, λ 0 is the wavelength of the microwave radiation; and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 171
Dependent Claim
35 words
The method according to claim 157, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.8.
Claim 172
Dependent Claim
35 words
The method according to claim 157, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.7.
Claim 173
Dependent Claim
35 words
The method according to claim 157, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.6.
Claim 174
Dependent Claim
35 words
The method according to claim 157, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.5.
Claim 175
Dependent Claim
35 words
The method according to claim 157, in the step of reducing the relative arcing potent is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.4.
Claim 176
Dependent Claim
34 words
The method according to claim 157, the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.3.
Claim 177
Dependent Claim
35 words
The method according to claim 157, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.2.
Claim 178
Dependent Claim
35 words
The method according to claim 157, wherein the step of reducing the relative arcing potential is sufficient to produce a value for the relative arcing potential in the range of about 0 to about 0.1.
Claim 179
Dependent Claim
92 words
The method according to claim 157, further comprising step of: selecting a shield having a height "h" and a range of diameters from a maximum diameter "d 2 " to a minimum diameter "d 1 ", such that: ##EQU82## is substantially not equal to ##EQU83## for all values of the diameter "D" w the range between "d 1 " and "d 2 ", where "N" and "M" are integers, for example, 0, 1, 2, 3, 4, etc., and "λ s " is the actual resonant wavelength of the microwaves in the shield.
Claim 180
Dependent Claim
263 words
A non-arcing food container having conductive shielding intended for use in a microwave oven having a frequency of about 2450 MHz, comprising: a generally cylindrical container, the container being essentially transparent to microwave radiation, the container having a height, the container having a bottom and an opening remote from the bottom, the container having a diameter of about 72 millimeters; a recessed lid, the lid mating with the opening in the container to sealingly engage the container, the lid having a conductive layer to inhibit microwaveradiation from entering the container; a conductive shield, the shield being formed around the container, the shield having a height of about 75 millimeters, the shield having a lower edge spaced from the bottom of the container, the shield having an upper edge overlapping the recessed lid to form a microwave resistant seal with the lid; a first food substance filling the bottom of the container and having a thickness between about 11 millimeters and about 18 millimeters, the first food substance intended to be heated by microwave radiation; a second food substance in the container, the second food substance intended to be substantially shielded from microwave radiation, the shield and lid substantially surrounding the top and sides of the second food substance; an edible third food substance in the container between the first food substance and the second food substance, the third food substance having a thickness between about 8 millimeters and about 10 millimeters; whereby the dimensions and geometry of the container, shield and food substances are selected to substantially avoid resonances and to minimize arcing.
Claim 181
Dependent Claim
263 words
A non-arcing food container having conductive shielding intended for use in a microwave oven having a frequency of about 2450 MHz, comprising: a generally cylindrical container, the container being essentially transparent to microwave radiation, the container having a height, the container having a bottom and an opening remote from the bottom, the container having a diameter of about 72 millimeters; a recessed lid, the lid mating with the opening in the container to sealingly engage the container, the lid having a conductive layer to inhibit microwaveradiation from entering the container; a conductive shield, the shield being formed around the container, the shield having a height of about 75 millimeters, the shield having a lower edge spaced from the bottom of the container, the shield having an upper edge overlapping the recessed lid to form a microwave resistant seal with the lid; a first food substance filling the bottom of the container and having a thickness between about 11 millimeters and about 18 millimeters, the first food substance intended to be heated by microwave radiation; a second food substance in the container, the second food substance intended to be substantially shielded from microwave radiation, the shield and lid substantially surrounding the top and sides of the second food substance; an edible third food substance in the container between the first food substance and the second food substance, the third food substance having a thickness between about 8 millimeters and about 10 millimeters; whereby the dimensions and geometry of the container, shield and food substances are selected to substantially avoid resonances and to minimize arcing.
Claim 182
Dependent Claim
24 words
The non-arcing food container according to claim 167, wherein: the conductive shield has overlapping ends separated by a dielectric material to dampen arcing voltages.
Claim 183
Dependent Claim
24 words
The non-arcing food container according to claim 168, wherein: the second food substance has a thickness between about 40 millimeters and about 57 millimeters.
Claim 184
Dependent Claim
18 words
The non-arcing food container according to claim 169, wherein: the container has a height of about 81.5 millimeters.
Claim 185
Dependent Claim
33 words
The non-arcing food container according to claim 168, wherein: the first food substance has dielectric properties including a dielectric constant E' of about 3.03 and a dielectric loss factor E' of about 0.67.
Claim 186
Dependent Claim
33 words
The non-arcing food container according to claim 168, wherein: the second food substnace has dielectric properties including a dielectric constant E' of about 5.96 and a dielectric loss factor E' of about 2.51.
Claim 187
Dependent Claim
43 words
The non-arcing food container according to claim 172, wherein: the third food substance has dielectric properties including a dielectric constant E' of about 8.41 and a dielectric loss factor E' of about 4.89, the third food substance being generally reflective of microwave radiation.
Claim 188
Dependent Claim
125 words
A non-arcing shielded microwave food container, comprising: a container containing a first food substance to be heated by microwaves and a second food substance to be shielded from microwaves, the container being adapted to be received into a microwave oven for heating; an overlapping conductive shield located in shielding relationship to the second food material, the shield having an electrical loop creating inductance "1", the shield having overlapping conductive plates separated by a dielectric material creating capacitance "c", the amount of overlap and spacing between the conductive plates being selected to reduce a relative arcing potential to substantially eliminate arcing, where: ##EQU84## where "w" is the frequency of microwave radiation, "1" is the inductance of the shield, and "c" is the capacitance of the shield.
Claim 189
Dependent Claim
125 words
A non-arcing shielded microwave food container, comprising: a container containing a first food substance to be heated by microwaves and a second food substance to be shielded from microwaves, the container being adapted to be received into a microwave oven for heating; an overlapping conductive shield located in shielding relationship to the second food material, the shield having an electrical loop creating inductance "1", the shield having overlapping conductive plates separated by a dielectric material creating capacitance "c", the amount of overlap and spacing between the conductive plates being selected to reduce a relative arcing potential to substantially eliminate arcing, where: ##EQU84## where "w" is the frequency of microwave radiation, "1" is the inductance of the shield, and "c" is the capacitance of the shield.
Claim 190
Dependent Claim
43 words
The microwave food container according to claim 174, wherein: the conductive shield has a height "h" which is substantially not equal to any integer multiple of a half wavelength "λ s " of the actual resonant wavelength of the microwaves in the shield.
Claim 191
Dependent Claim
62 words
The microwave food container according to claim 174 or claim 175, further comprising: a recessed conductive top, the top being in sealing engagement with the container, the top being recess where edges of the top are located remote from the second food substance so that electrical fields induced in the conductive top by microwave radiation do not overheat the second food substance.
Claim 192
Dependent Claim
110 words
A non-arcing food package for a microwave environment using conductive shielding, comprising: a container having a first food substance to be heated by microwaves and a second food substance to be at least partially shielded from microwaves; a conductive shield located in shielding relationship to the second food substance, the shield having a height "h" and a width "w", the geometry of the shield being selected so that: ##EQU85## is not equal to ##EQU86## where "λ s " is the actual wavelength of the microwaves in the shield, and "N" and "M" are integers, for example, 0, 1, 2, 3, 4, etc.; thereby substantially avoiding resonance and substantially eliminating arcing.
Claim 193
Dependent Claim
110 words
A non-arcing food package for a microwave environment using conductive shielding, comprising: a container having a first food substance to be heated by microwaves and a second food substance to be at least partially shielded from microwaves; a conductive shield located in shielding relationship to the second food substance, the shield having a height "h" and a width "w", the geometry of the shield being selected so that: ##EQU85## is not equal to ##EQU86## where "λ s " is the actual wavelength of the microwaves in the shield, and "N" and "M" are integers, for example, 0, 1, 2, 3, 4, etc.; thereby substantially avoiding resonance and substantially eliminating arcing.
Claim 194
Independent Claim
168 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a food container having a food material to be heated by microwave radiation and to be at least partially shielded from microwave radiation; providing a conductive shield around a part of the food container, the conductive shield being located in microwave shielding relationship to a portion of the food material, the conductive shield having a first end and a second end, said shield having height and circumference; overlapping the first end of the shield over the second end of the shield to form an overlapped shield, where the first and second ends of the overlapped shield are separated by a dielectric material, the amount of the overlap being selected to damp potential arcing currents; selecting the height and circumference of said shield to be not equal to any multiple of a half wavelength of the microwave radiation in the shield thereby avoiding resonance of the shield to minimize arcing.
Claim 195
Independent Claim
168 words
A method of substantially eliminating arcing in a food container for a microwave environment, comprising the steps of: providing a food container having a food material to be heated by microwave radiation and to be at least partially shielded from microwave radiation; providing a conductive shield around a part of the food container, the conductive shield being located in microwave shielding relationship to a portion of the food material, the conductive shield having a first end and a second end, said shield having height and circumference; overlapping the first end of the shield over the second end of the shield to form an overlapped shield, where the first and second ends of the overlapped shield are separated by a dielectric material, the amount of the overlap being selected to damp potential arcing currents; selecting the height and circumference of said shield to be not equal to any multiple of a half wavelength of the microwave radiation in the shield thereby avoiding resonance of the shield to minimize arcing.
Claim 196
Dependent Claim
139 words
Method according to claim 178, wherein the dimension of the shield are selected to reduce a relative arcing potential to a level where arcing is substantially avoided, the relative arcing potential being defined by: ##EQU87## where D is the diameter of the shield, h is the height of the shield, L is the distance that first end of the shield overlaps the second end of the shield, K is the dielectric constant of the dielectric material between the first and second ends of the shields, d is the distance that the first and second ends of the shield are spaced apart, λ 0 is the wavelength of the microwave radiation; and, reducing the relative arcing potential by selecting dimensions for the shield which reduce the value of the relative arcing potential to a level where arcing is substantially avoided.
Claim 197
Dependent Claim
261 words
A non-arcing package for the differential heating of food with microwave radiation where potential arcing currents are damped by a shield having a nonresonant combination of capacitance and inductance, comprising: a microwave food container, the food container having a food material to be heated by microwave radiation and to be at least partially shielded from microwave radiation; a conductive shield shielding part of the food container in proximity to the portion of food material to be at least partially shielded, the shield being generally electrically looped, the shield, having some inductance, the shield having a first end, the shield having a second end which overlaps the first end for a distance "L", the first end and the second end being spaced apart a distance "d", the first end and the second end being separated by dielectric material having a dielectric constant of "K", the shield having some capacitance, the looped shield having a diameter of "D" and a height of "h"; and, the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectrical material between the first and second ends of the shield being selected to damp potential arcing currents by reducing the relative arcing potential defined by: ##EQU88## where "λ.sub. " is the wavelength of the microwave radiation; and, whereby the shield is provided with a nonresonant combination of capacitance and inductance to damp potential arcing currents thereby substantially avoiding arcing.
Claim 198
Dependent Claim
261 words
A non-arcing package for the differential heating of food with microwave radiation where potential arcing currents are damped by a shield having a nonresonant combination of capacitance and inductance, comprising: a microwave food container, the food container having a food material to be heated by microwave radiation and to be at least partially shielded from microwave radiation; a conductive shield shielding part of the food container in proximity to the portion of food material to be at least partially shielded, the shield being generally electrically looped, the shield, having some inductance, the shield having a first end, the shield having a second end which overlaps the first end for a distance "L", the first end and the second end being spaced apart a distance "d", the first end and the second end being separated by dielectric material having a dielectric constant of "K", the shield having some capacitance, the looped shield having a diameter of "D" and a height of "h"; and, the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, the spacing "d" between the ends of the shield, and the dielectric constant "K" of the dielectrical material between the first and second ends of the shield being selected to damp potential arcing currents by reducing the relative arcing potential defined by: ##EQU88## where "λ.sub. " is the wavelength of the microwave radiation; and, whereby the shield is provided with a nonresonant combination of capacitance and inductance to damp potential arcing currents thereby substantially avoiding arcing.
Claim 199
Dependent Claim
64 words
The package according to claim 180, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential from about 0 to about 0.5.
Claim 200
Dependent Claim
64 words
The package according to claim 180, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, and the dielectric constant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential from about 0 to about 0.4.
Claim 201
Dependent Claim
64 words
The package according to claim 180, wherein: the diameter "D" and height "h" of the shield, the amount of overlap "L" between the first and second ends of the shield, and the dielectric contstant "K" of the dielectric material between the first and second ends of the shield are selected to produce a value for the arcing potential from about 0 to about 0.3.
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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) | 1992-07-24 | 1993-01-23 | 1993-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-24 | 1997-01-23 | 1997-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-24 | 2001-01-23 | 2001-07-25 | $7700.00 | Window Closed / Lapsed |