Patent US3869596A successfully refreshed from Google Patents.
US3869596A
Expired / Lapsed
US
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Cookware heater
Assignee: Safeway Products Inc
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Filing: 1973-09-28
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Granted: 1975-03-04
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Expires: 1993-09-28
Abstract
Abstract A cookware heater and method of manufacture thereof is presented wherein a heating circuit of the printed circuit foil type is bonded to a ceramic or metallic cookware item. A layer of high temperature dielectric material is sandwiched between the heater circuit foil and the cookware item, and the coefficients of expansion of the cookware material, and the heater circuit foil are closely matched to each other.
Inventors
- 👤 John R Howie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:52
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/20; H05B3/22; H05B3/26; A; A47; A47J; A47J27/00; A47J27/004; H05B2203/00; H05B2203/002; H05B2203/003; H05B2203/013; H05B2203/017
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
77 words
A COOKING UNIT INCLUDING: A COOKING ELEMENT FORMED OF MATERIAL SELECTED FROM THE GROUP CONSISTING OF GLASS, CERAMIC AND METAL; A BASE PORTION PART OF SAID COOKING ELEMENT HAVING A MAT SURFACE AND BEING ELECTRICALLY INSULATING; A LAYER OF DIELECTRIC MATERIAL BONDED TO SAID MAT SURFACE OF THE BASE PORTION; ELECTRO-CONDUCTIVE CIRCUIT FOIL MEANS ADHESIVELY BONDED TO SAID LAYER OF DIELECTRIC MATERIAL, THE COEFFICIENT OF THERMAL EXPANSION OF SAID FOIL MEANS BEING NOT LESS THAN THE COEFFI-
Claim 2
Dependent Claim
77 words
A COOKING UNIT INCLUDING: A COOKING ELEMENT FORMED OF MATERIAL SELECTED FROM THE GROUP CONSISTING OF GLASS, CERAMIC AND METAL; A BASE PORTION PART OF SAID COOKING ELEMENT HAVING A MAT SURFACE AND BEING ELECTRICALLY INSULATING; A LAYER OF DIELECTRIC MATERIAL BONDED TO SAID MAT SURFACE OF THE BASE PORTION; ELECTRO-CONDUCTIVE CIRCUIT FOIL MEANS ADHESIVELY BONDED TO SAID LAYER OF DIELECTRIC MATERIAL, THE COEFFICIENT OF THERMAL EXPANSION OF SAID FOIL MEANS BEING NOT LESS THAN THE COEFFI-
Claim 3
Dependent Claim
26 words
A cooking unit as in claim 1 wherein: said layer of dielectric material is a discrete sheet of flexible material adhesively bonded to said base portion.
Claim 4
Dependent Claim
53 words
A cooking unit as in claim 2 including: a layer of adhesive material bonding said dielectric sheet to said base, said layer of adhesive material between said base portion and said dielectric sheet being of the same material as the layer of adhesive material between said dielectric sheet and said circuit foil means.
Claim 5
Dependent Claim
30 words
A cooking unit as in claim 1 wherein: said cooking element is formed of metal; and said base portion is a layer of electrically insulating material applied to said metal.
Claim 6
Dependent Claim
14 words
A cooking unit as in claim 4 wherein: said electrically insulating material is porcelain.
Claim 7
Dependent Claim
119 words
A cooking unit including a cooking element formed of material selected from the group consisting of glass and ceramic; a base portion part of said cooking element having a mat surface; a layer of dielectric material bonded to said mat surface of the base portion; electro-conductive circuit foil means adhesively bonded to said layer of dielectric material, the coefficient of thermal expansion of said foil means being not less than the coefficient of thermal expansion of said cooking unit material and not more than ten times the coefficient of thermal expansion of said cooking unit material; and a layer of adhesive material bonding said circuit foil means to said layer of dielectric material, said adhesive remaining flexible after curing.
Claim 8
Dependent Claim
119 words
A cooking unit including a cooking element formed of material selected from the group consisting of glass and ceramic; a base portion part of said cooking element having a mat surface; a layer of dielectric material bonded to said mat surface of the base portion; electro-conductive circuit foil means adhesively bonded to said layer of dielectric material, the coefficient of thermal expansion of said foil means being not less than the coefficient of thermal expansion of said cooking unit material and not more than ten times the coefficient of thermal expansion of said cooking unit material; and a layer of adhesive material bonding said circuit foil means to said layer of dielectric material, said adhesive remaining flexible after curing.
Claim 9
Dependent Claim
26 words
A cooking unit as in claim 6 wherein: said layer of dielectric material is a discrete sheet of flexible material adhesively bonded to said base portion.
Claim 10
Dependent Claim
53 words
A cooking unit as in claim 7 including: a layer of adhesive material bonding said dielectric sheet to said base, said layer of adhesive material between said base portion and said dielectric sheet being of the same material as the layer of adhesive material between said dielectric sheet and said circuit foil means.
Claim 11
Dependent Claim
20 words
A cooking unit as in claim 5 wherein: said layer of dielectric material is a sheet of alumina-silica fiber material.
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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) | 1978-03-03 | 1978-09-02 | 1979-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-03 | 1982-09-02 | 1983-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-03 | 1986-09-02 | 1987-03-04 | $7700.00 | Window Closed / Lapsed |