Patent US4137519A successfully refreshed from Google Patents.
US4137519A
Expired / Lapsed
US
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Resistor material, resistor made therefrom and method of making the same
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1977-10-25
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Granted: 1979-01-30
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Expires: 1997-10-25
Abstract
Abstract A vitreous enamel resistor material which includes a mixture of fine particles of tungsten carbide, tungsten trioxide and a glass frit. The resistor material may also include fine particles of tungsten. The resistor material is made into a resistor by coating the mixture on a substrate, firing the coating at a temperature at which the glass frit melts, and then cooling the coated substrate to form the resistor having a layer of glass with the particles dispersed therein.
Inventors
- 👤 Malcolm H. Hodge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:57
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06513; H01C17/0652; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
17 words
A resistor material comprising a mixture of particles of tungsten carbide, tungsten trioxide, and a glass frit.
Claim 2
Dependent Claim
17 words
A resistor material comprising a mixture of particles of tungsten carbide, tungsten trioxide, and a glass frit.
Claim 3
Dependent Claim
17 words
A resistor material in accordance with claim 1 in which the mixture also contains particles of tungsten.
Claim 4
Dependent Claim
54 words
A resistor material in accordance with claim 1 in which the ingredients are present in the mixture in the amount of by weight 35% to 75% tungsten carbide, 2% to 20% tungsten trioxide, tungsten in the amount of 0 to 50% of the amount of tungsten carbide and the remaining being the glass frit.
Claim 5
Dependent Claim
17 words
A resistor material in accordance with claim 3 in which the glass frit is a borosilicate glass.
Claim 6
Dependent Claim
19 words
A resistor material in accordance with claim 4 in which the glass frit is an alkaline earth borosilicate glass.
Claim 7
Dependent Claim
45 words
An electrical resistor comprising an electrically insulating substrate and a resistor material on a surface of said substrate, said resistor material comprising a glass layer having embedded therein and dispersed therethroughout a mixture of particles of tungsten carbide and tungsten dioxide reduced from tungsten trioxide.
Claim 8
Dependent Claim
45 words
An electrical resistor comprising an electrically insulating substrate and a resistor material on a surface of said substrate, said resistor material comprising a glass layer having embedded therein and dispersed therethroughout a mixture of particles of tungsten carbide and tungsten dioxide reduced from tungsten trioxide.
Claim 9
Dependent Claim
22 words
An electrical resistor in accordance with claim 6 in which the resistor material also includes particles of tungsten in the glass layer.
Claim 10
Dependent Claim
43 words
An electrical resistor in accordance with claim 7 in which the resistor material includes by weight 35% to 75% tungsten carbide, tungsten dioxide reduced from 2% to 20% tungsten trioxide, and tungsten in the amount of 0 to 50% of the tungsten carbide.
Claim 11
Dependent Claim
16 words
An electrical resistor in accordance with claim 8 in which the glass is a borosilicate glass.
Claim 12
Dependent Claim
18 words
An electrical resistor in accordance with claim 9 in which the glass is an alkaline earth borosilicate glass.
Claim 13
Independent Claim
61 words
A method of making an electrical resistor comprising the steps of mixing together particles of tungsten carbide, tungsten trioxide and a glass frit, coating the mixture onto the surface of a substrate of an electrically insulating material, firing said coated substrate in a non-oxidizing atmosphere at a temperature at which the glass frit becomes molten, and then cooling said coated substrate.
Claim 14
Independent Claim
61 words
A method of making an electrical resistor comprising the steps of mixing together particles of tungsten carbide, tungsten trioxide and a glass frit, coating the mixture onto the surface of a substrate of an electrically insulating material, firing said coated substrate in a non-oxidizing atmosphere at a temperature at which the glass frit becomes molten, and then cooling said coated substrate.
Claim 15
Dependent Claim
19 words
The method of claim 11 in which the non-oxidizing atmosphere in which the coated substrate is fired is nitrogen.
Claim 16
Dependent Claim
29 words
The method of making an electrical resistor in accordance with claim 11 including mixing particles of tungsten with the particles of tungsten carbide, tungsten trioxide and the glass frit.
Claim 17
Dependent Claim
56 words
The method of making an electrical resistor in accordance with claim 13 in which the proportion of the ingredients in the mixture are by weight 35% to 75% tungsten carbide, 2% to 20% tungsten trioxide, tungsten in the amount of 0 to 50% of the amount of tungsten carbide, and the remaining being the glass frit.
Claim 18
Dependent Claim
68 words
The method of making an electrical resistor in accordance with claim 14 in which the ingredients are mixed together in a liquid vehicle, the resulting mixture is heated to remove the liquid vehicle and dry the mixture, and the dry mixture is then blended with a vehicle suitable for applying the mixture to the substrate, and the non-oxidizing atmosphere in which the coated substrate is fired is nitrogen.
Claim 19
Dependent Claim
60 words
An electrical resistor of the vitreous enamel type made by mixing together particles of tungsten carbide, tungsten trioxide and a glass frit, coating the mixture onto the surface of a substrate of an electrically insulating material, firing said coated substrate in a non-oxidizing atmosphere at a temperature at which the glass frit becomes molten, and then cooling said coated substrate.
Claim 20
Dependent Claim
60 words
An electrical resistor of the vitreous enamel type made by mixing together particles of tungsten carbide, tungsten trioxide and a glass frit, coating the mixture onto the surface of a substrate of an electrically insulating material, firing said coated substrate in a non-oxidizing atmosphere at a temperature at which the glass frit becomes molten, and then cooling said coated substrate.
Claim 21
Dependent Claim
28 words
An electrical resistor of the vitreous enamel type made in accordance with claim 16 in which the non-oxidizing atmosphere in which the coated substrate is fired is nitrogen.
Claim 22
Dependent Claim
45 words
An electrical resistor of the vitreous enamel type made in accordance with claim 16 which includes mixing particles of tungsten with the particles of tungsten carbide, tungsten trioxide and the glass frit, and the non-oxidizing atmosphere in which the coated substrate is fired is nitrogen.
Claim 23
Dependent Claim
58 words
An electrical resistor of the vitreous enamel type made in accordance with claim 18 in which the proportion of the ingredients in the mixture are by weight 35% to 75% tungsten carbide, 2% to 20% tungsten trioxide, tungsten in the amount of 0 to 50% of the amount of tungsten carbide, and the remaining being the glass frit.
Claim 24
Dependent Claim
70 words
An electrical resistor of the vitreous enamel type made in accordance with claim 19 in which the ingredients are mixed together in a liquid vehicle, the resulting mixture is heated to remove the liquid vehicle and dry the mixture, and the dry mixture is then blended with a vehicle suitable for applying the mixture to the substrate, and the non-oxidizing atmosphere in which the coated substrate is fired is nitrogen.
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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) | 1982-01-29 | 1982-07-31 | 1983-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-29 | 1986-07-31 | 1987-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-29 | 1990-07-31 | 1991-01-30 | $7700.00 | Window Closed / Lapsed |