US5593610A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Container for active microwave heating
Assignee: Hormel Foods LLC
•
Filing: 1995-08-04
•
Granted: 1997-01-14
•
Expires: 2015-08-04
Abstract
Abstract An microwave container with synergistic active elements provides more uniform heating than prior art containers, and is more tolerant of variations in food product, load and heating conditions. The active elements (which are conductive and microwave opaque) include an annular ring in the base of the container, a band extending from the base of the side walls up the walls to a level approximately even with the anticipated fill level in the container, a lip extending from the bottom of the side walls onto the base, and at least one, preferably three cooperative active elements in the lid of the container. These containers can be used for thawing and cooking frozen, uncooked meats and other foods, with which prior art containers produced unsatisfactory results.
Inventors
- 👤 Phillip L. Minerich
- 👤 Bryan C. Hewitt
- 👤 Cindy M. Lacroix
- 👤 Melville D. Ball
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:18
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/647; H05B6/6491; H05B6/6494; B; B65; B65D; B65D81/00; B65D81/34; B65D81/3446; B65D81/3453; B65D2581/00; B65D2581/34; B65D2581/3401; B65D2581/3435; B65D2581/3437; B65D2581/3439; B65D2581/344; B65D2581/3471; B65D2581/3472; B65D2581/3486; B65D2581/3487; B65D2581/3489; Y; Y10; Y10S; Y10S99/00; Y10S99/14
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
218 words
In a container comprising a tray having an open end, a closed base and side walls extending from said closed base to said open end, and a lid covering said open end, the improvement wherein: said side walls comprise a microwave transparent material which extends from said closed base to said open end, and conductive, microwave opaque material which extends from said side walls onto said closed base and forms a lip at the edge of said closed base; said closed base comprises an annular base ring of conductive, microwave opaque material encompassing a first area of microwave transparent material, and a second area of microwave transparent material between said annular base ring and said lip, said annular base ring and said lip being designed and adapted to establish boundary conditions at said base ring and at said lip that produce a central energy maxima within said first area and a subsidiary energy maxima in said second area; said lid comprises a microwave transparent material and a first conductive, microwave opaque element, said element being separated from said side walls by an annular area of said microwave transparent material and designed and adapted to enhance microwave intensity under said element; whereby said side walls, said base and said lid co-operate to produce more uniform heating within said container.
Claim 2
Dependent Claim
218 words
In a container comprising a tray having an open end, a closed base and side walls extending from said closed base to said open end, and a lid covering said open end, the improvement wherein: said side walls comprise a microwave transparent material which extends from said closed base to said open end, and conductive, microwave opaque material which extends from said side walls onto said closed base and forms a lip at the edge of said closed base; said closed base comprises an annular base ring of conductive, microwave opaque material encompassing a first area of microwave transparent material, and a second area of microwave transparent material between said annular base ring and said lip, said annular base ring and said lip being designed and adapted to establish boundary conditions at said base ring and at said lip that produce a central energy maxima within said first area and a subsidiary energy maxima in said second area; said lid comprises a microwave transparent material and a first conductive, microwave opaque element, said element being separated from said side walls by an annular area of said microwave transparent material and designed and adapted to enhance microwave intensity under said element; whereby said side walls, said base and said lid co-operate to produce more uniform heating within said container.
Claim 3
Dependent Claim
43 words
A container according to claim 1 wherein said lid further comprises at least one additional conductive, microwave opaque element positioned between said first element and said side walls and separated from said first element, and from said side walls, by microwave transparent material.
Claim 4
Dependent Claim
57 words
A container according to claim 2 having at least two additional conductive, microwave opaque elements positioned between said first conductive, microwave opaque element and said sidewalls, each of said additional elements comprising a section of an interrupted annular lid ring, said ring being interrupted by microwave transparent material between ends of said additional conductive, microwave opaque elements.
Claim 5
Dependent Claim
46 words
A container according to claim 3 wherein said first element and said interrupted annular lid ring are oval, said interrupted annular lid ring is about 10 to 20 mm wide and the distance between said first element and said ring is about 10 to 25 mm.
Claim 6
Dependent Claim
31 words
A container according to claim 4 wherein said interrupted annular lid ring is about 15 mm wide and the distance between said first element and said ring is about 10 mm.
Claim 7
Dependent Claim
64 words
A container according to claim 3 wherein the first element and the open end of the tray are oval, the ratio of the length of the first element to the length of the open end of the tray, and the ratio of the width of the first element to the width of the open end of the tray, are between about 0.2 and 0.3.
Claim 8
Dependent Claim
50 words
A container according to claim 6 wherein the ratio of the length of the element to the length of the open end of the tray is about 0.27, and the ratio of the width of the element to the width of the open end of the tray is about 0.23.
Claim 9
Dependent Claim
33 words
A container according to claim 6 wherein the ratio between the diameter of the first element and the diameter of the open end is substantially constant at any angular position around the tray.
Claim 10
Dependent Claim
16 words
A container according to claim 1 wherein said closed base and said open end are oval.
Claim 11
Dependent Claim
32 words
A container according to claim 9 wherein said open end of said tray is larger than said closed base, and said side walls taper outwardly from said base to said open end.
Claim 12
Dependent Claim
44 words
A container according to claim 9 wherein said open end is about 185 mm long by about 125 mm wide, said closed base is about 165 mm long by about 105 mm wide, and the height of said side walls is about 42 mm.
Claim 13
Dependent Claim
38 words
A container according to claim 11 wherein the ratio of the diameter of the said annular base ring to the diameter of said base at any angular position around said container is between about 0.4 and about 0.7.
Claim 14
Dependent Claim
18 words
A container according to claim 12 wherein the said ratio does not vary by more than about 0.15.
Claim 15
Dependent Claim
38 words
A container according to claim 11 wherein the ratio of the diameter of the said annular base ring to the diameter of said base at any annular position around said container is between about 0.5 and about 0.6.
Claim 16
Dependent Claim
34 words
A container according to claim 11 wherein the ratio of the diameter of the said annular base ring to the diameter of said base at any annular position around said container is about 0.55.
Claim 17
Dependent Claim
23 words
A container according to claim 1 wherein the conductive material in said side walls extends for the entire circumference of said side walls.
Claim 18
Dependent Claim
32 words
A container according to claim 16 wherein the conductive material in the side walls extends from said closed base up said side walls for a distance of about 26 to 31 millimeters.
Claim 19
Dependent Claim
29 words
A container according to claim 1 wherein said conductive material in said side walls extends onto said closed base for a distance of about 2 mm to 10 mm.
Claim 20
Dependent Claim
20 words
A container according to claim 1 further comprising a flange extending outwardly from said side walls at said open end.
Claim 21
Dependent Claim
36 words
A container according to claim 19 wherein said conductive material in said side wall extends from said closed base to said open end and extends outwardly along said flange for the entire width of said flange.
Claim 22
Dependent Claim
335 words
A package adapted for microwave defrosting and cooking or heating of frozen foods comprising: an oval tray having an open end, a closed base that is smaller than said open end, and side walls tapering outwardly from said closed base to said open end, said side walls comprising a microwave transparent material which extends from said closed base to said open end, and conductive, microwave opaque material which extends from said side walls onto said closed base and forms a lip at the edge of said closed base; said closed base comprising an annular base ring of conductive, microwave opaque material encompassing a first area of microwave transparent material, and a second area of microwave transparent material between said annular base ring and said lip, said annular ring and said lip being designed and adapted to establish boundary conditions at said ring and at said lip that produce a central energy maxima within said first area and a subsidiary energy maxima in said second area: an oval lid that covers the open end of said tray, said lid comprising microwave transparent material, a central patch of conductive, microwave opaque material; and at least two additional patches of conductive, microwave opaque material positioned between said central patch and said sidewalls, each of said additional patches comprising a section of an interrupted annular lid ring that is separated from said central patch by an annular ring of microwave transparent material, said annular lid ring being interrupted by microwave transparent material between ends of said patches of conductive material and said annular lid ring being separated from said side walls by an annular area of microwave transparent material, said central patch being designed and adapted to enhance microwave intensity under said lid in the central region of the container, and said interrupted annular ring being designed to provide localized enhancement of heating in the area beneath said annular lid ring; whereby said side walls, said base and said lid co-operate to produce more uniform heating within said container.
Claim 23
Dependent Claim
335 words
A package adapted for microwave defrosting and cooking or heating of frozen foods comprising: an oval tray having an open end, a closed base that is smaller than said open end, and side walls tapering outwardly from said closed base to said open end, said side walls comprising a microwave transparent material which extends from said closed base to said open end, and conductive, microwave opaque material which extends from said side walls onto said closed base and forms a lip at the edge of said closed base; said closed base comprising an annular base ring of conductive, microwave opaque material encompassing a first area of microwave transparent material, and a second area of microwave transparent material between said annular base ring and said lip, said annular ring and said lip being designed and adapted to establish boundary conditions at said ring and at said lip that produce a central energy maxima within said first area and a subsidiary energy maxima in said second area: an oval lid that covers the open end of said tray, said lid comprising microwave transparent material, a central patch of conductive, microwave opaque material; and at least two additional patches of conductive, microwave opaque material positioned between said central patch and said sidewalls, each of said additional patches comprising a section of an interrupted annular lid ring that is separated from said central patch by an annular ring of microwave transparent material, said annular lid ring being interrupted by microwave transparent material between ends of said patches of conductive material and said annular lid ring being separated from said side walls by an annular area of microwave transparent material, said central patch being designed and adapted to enhance microwave intensity under said lid in the central region of the container, and said interrupted annular ring being designed to provide localized enhancement of heating in the area beneath said annular lid ring; whereby said side walls, said base and said lid co-operate to produce more uniform heating within said container.
Claim 24
Dependent Claim
242 words
A package adapted for heating in a microwave oven comprising: a tray having an open end, a closed base and side walls extending from said closed base to said open end; said side walls comprising a microwave transparent material which extends from said closed base to said open end, and conductive, microwave opaque material which extends from said side walls onto said closed base and forms a lip at the edge of said closed base; said closed base comprising an annular base ring of conductive, microwave opaque material encompassing a first area of microwave transparent material, and a second area of microwave transparent material between said annular base ring and said lip, said annular base ring and said lip being designed and adapted to establish boundary conditions at said base ring and at said lip that produce a central energy maxima within said first area and a subsidiary energy maxima in said second area; a body of material to be heated positioned within said tray; a lid covering said open end of said tray and said body of material to be heated, said lid comprising microwave transparent material and a first, conductive, microwave opaque element, said element being separated from said side walls by a an annular area of said microwave transparent material and designed and adapted to enhance microwave intensity under said element; whereby said side walls, said base and said lid co-operate to produce more uniform heating within said container.
Claim 25
Dependent Claim
242 words
A package adapted for heating in a microwave oven comprising: a tray having an open end, a closed base and side walls extending from said closed base to said open end; said side walls comprising a microwave transparent material which extends from said closed base to said open end, and conductive, microwave opaque material which extends from said side walls onto said closed base and forms a lip at the edge of said closed base; said closed base comprising an annular base ring of conductive, microwave opaque material encompassing a first area of microwave transparent material, and a second area of microwave transparent material between said annular base ring and said lip, said annular base ring and said lip being designed and adapted to establish boundary conditions at said base ring and at said lip that produce a central energy maxima within said first area and a subsidiary energy maxima in said second area; a body of material to be heated positioned within said tray; a lid covering said open end of said tray and said body of material to be heated, said lid comprising microwave transparent material and a first, conductive, microwave opaque element, said element being separated from said side walls by a an annular area of said microwave transparent material and designed and adapted to enhance microwave intensity under said element; whereby said side walls, said base and said lid co-operate to produce more uniform heating within said container.
Claim 26
Dependent Claim
17 words
A package according to claim 22 wherein said body of material to be heated comprises a foodstuff.
Claim 27
Dependent Claim
13 words
A package according to claim 22 wherein said foodstuff is frozen and uncooked.
Claim 28
Dependent Claim
54 words
A package according to claim 22 wherein said band of conductive material in said side walls extends from said closed base up said side walls to a level below the top of the material to be heated and the portion of said side walls between said level and said open end is microwave transparent.
References Cited (Backward Citations)
US3240610A
Cited
US3777099A
Cited
US3985991A
Cited
US3835280A
Cited
US3845266A
Cited
US4081646A
Cited
US4190757A
Cited
US4709129A
Cited
US4495392A
Cited
US4230924A
Cited
CA1082655A
Cited
US4223194A
Cited
US4369346A
Cited
US4351997A
Cited
US4320274A
Cited
US4345133A
Cited
US4481392A
Cited
US4501946A
Cited
US4398994A
Cited
US4517045A
Cited
CA1202088A
Cited
US4656325A
Cited
US4594492A
Cited
US4552614A
Cited
US4675697A
Cited
US4620169A
Cited
US4610755A
Cited
US4878765A
Cited
US4866234A
Cited
US4676428A
Cited
US4874618A
Cited
US4892213A
Cited
US4960598A
Cited
US4831224A
Cited
US4777053A
Cited
US4685997A
Cited
US4940168A
Cited
US4689458A
Cited
US4926020A
Cited
US4703148A
Cited
US4851631A
Cited
US4874917A
Cited
US4888459A
Cited
US4786773A
Cited
US4917748A
Cited
US4915780A
Cited
US4877933A
Cited
US4814568A
Cited
US4916280A
Cited
US4954356A
Cited
US4940158A
Cited
US4962000A
Cited
US4894503A
Cited
US4882463A
Cited
US4927991A
Cited
US5079397A
Cited
US4894247A
Cited
US4933193A
Cited
US4950524A
Cited
US4972059A
Cited
US4939332A
Cited
US4938990A
Cited
US4943439A
Cited
US4876427A
Cited
US4866232A
Cited
US4924048A
Cited
US4948932A
Cited
US4876423A
Cited
US4859822A
Cited
US4936935A
Cited
US4904836A
Cited
US4900762A
Cited
US4992638A
Cited
US4896009A
Cited
US4883935A
Cited
US4877932A
Cited
US4911938A
Cited
US4883936A
Cited
US4901911A
Cited
US4970360A
Cited
US4890439A
Cited
US5310980A
Cited
US4933526A
Cited
US5071710A
Cited
US4990735A
Cited
US4933525A
Cited
US4937410A
Cited
US4950859A
Cited
US4965424A
Cited
US4924049A
Cited
US4935377A
Cited
US4962293A
Cited
US4933528A
Cited
US5126518A
Cited
US4972058A
Cited
US5117078A
Cited
US5213902A
Cited
US5126520A
Cited
US5391430A
Cited
US5468939A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-01-14 | 2000-07-15 | 2001-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-14 | 2004-07-15 | 2005-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-14 | 2008-07-15 | 2009-01-14 | $7700.00 | Window Closed / Lapsed |