US3974360A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical heating unit incorporating protective PbTiO3 overglaze
Assignee: Corning Glass Works
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Filing: 1975-09-19
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Granted: 1976-08-10
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Expires: 1995-09-19
Abstract
Abstract An electrical heating unit of the integral element type, comprising a platinum film heating element bonded to a supporting ceramic plate, wherein the platinum film heating element is electrically stabilized and physically protected by a lead titanate overglaze, is described.
Inventors
- 👤 Joseph N. Panzarino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:59
CPC Classifications
C; C03; C03C; C03C17/00; C03C17/34; C03C17/36; C03C17/3602; C03C17/3605; C03C17/3649; C03C17/3655; C03C8/00; C03C8/02; C03C8/10; C03C8/12; H; H05; H05B; H05B3/00; H05B3/20; H05B3/22; H05B3/26; H05B3/265; H05B3/68; H05B3/74; C03C2205/00; C03C2205/02; C03C2209/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
115 words
An electrical heating unit comprising: a. a ceramic plate having a smooth upper heating surface and a smooth lower surface for supporting an electrical heating element; b. an electrical heating element bonded to the lower surface of the ceramic plate, said element including a noble metal film which forms at least one continuous heating strip and consists at least predominantly of platinum; c. a dense, non-porous lead titanate glaze bonded to the noble metal film and adjacent portions of the lower surface of the ceramic plate, said glaze consisting essentially, in weight percent on the oxide basis, of about 62-68% PbO, 12-16% TiO 2 , 14-20% SiO 2 and 2-4% Al 2 O 3 .
Claim 2
Dependent Claim
115 words
An electrical heating unit comprising: a. a ceramic plate having a smooth upper heating surface and a smooth lower surface for supporting an electrical heating element; b. an electrical heating element bonded to the lower surface of the ceramic plate, said element including a noble metal film which forms at least one continuous heating strip and consists at least predominantly of platinum; c. a dense, non-porous lead titanate glaze bonded to the noble metal film and adjacent portions of the lower surface of the ceramic plate, said glaze consisting essentially, in weight percent on the oxide basis, of about 62-68% PbO, 12-16% TiO 2 , 14-20% SiO 2 and 2-4% Al 2 O 3 .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-10 | 1980-02-09 | 1980-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-10 | 1984-02-09 | 1984-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-10 | 1988-02-09 | 1988-08-10 | $7700.00 | Window Closed / Lapsed |