Patent US989900A successfully refreshed from Google Patents.
Patent US3645784A successfully refreshed from Google Patents.
US3645784A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vitreous enamel resistor
Assignee: Sprague Electric Co
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Filing: 1969-12-18
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Granted: 1972-02-29
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Expires: 1989-12-18
Abstract
Abstract Fused vitreous enamel wire-wound resistor formed by roll coating the surface of the wire and core with a fluid vehicle containing a fused ground vitreous enamel frit dispersed therein, and then heat treating so as to drive off the vehicle and remelt the fused enamel frit.
Inventors
- 👤 Walter Helgeland
- 👤 James B Lazott
- 👤 Philip J Duke
- 👤 William J Taggart
- 👤 George W Heacox
- 👤 Abe Brandsma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:20
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/02; C; C23; C23D; C23D5/00; C23D5/005
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
31 words
The method of claim 1 including a further step of applying an outer coating of vitreous enamel over said protective layer by flame spraying a vitreous enamel frit onto said layer.
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) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |