US3883307A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas analyzer resistance element
Assignee: Ambac Industries Inc
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Filing: 1973-12-19
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Granted: 1975-05-13
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Expires: 1993-12-19
Abstract
Abstract A catalytic resistance element for use in a gas analyzer has an outer layer formed of particles of a metallic oxide, such as beryllium or aluminum, of about one micron average size, the outer layer preferably being of from about 100 to about 500 microns in thickness. The oxide particles have catalytic coatings formed by mixing the particles with a solution of a compound which is decomposed by heating to coat the particles with the catalyst and heating the mixture to cause such decomposition and coating. The outer layer is applied by mixing the oxide particles with binder solution, and applying drops of the mixture to the resistance element.
Inventors
- 👤 Young Ho Kim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:28
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/14; G01N27/16; B; B01; B01J; B01J35/00; B01J35/30; B01J35/391; B01J35/395
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
55 words
A CATALYTIC COMBUSTION RESISTANCE ELEMENT COMPRISING A CERAMIC COATED WIRE OVER WHICH A CATALYTIC LAYER IS FORMED, IN WHICH THE CATALYTIC LAYER COMPRISES INDIVIDUAL PARTICLES OF A POWDERED OXIDE SELECTED FROM THE CLASS OF OXIDES CONSISTING OF ALUMINA AND BERYLLIA, EACH OF SAID PARTICLES BEING INDIVIDUALLY COATED WITH A METALLIC CATALYST, SAID POWDERED PARTICLES BEING
Claim 2
Dependent Claim
55 words
A CATALYTIC COMBUSTION RESISTANCE ELEMENT COMPRISING A CERAMIC COATED WIRE OVER WHICH A CATALYTIC LAYER IS FORMED, IN WHICH THE CATALYTIC LAYER COMPRISES INDIVIDUAL PARTICLES OF A POWDERED OXIDE SELECTED FROM THE CLASS OF OXIDES CONSISTING OF ALUMINA AND BERYLLIA, EACH OF SAID PARTICLES BEING INDIVIDUALLY COATED WITH A METALLIC CATALYST, SAID POWDERED PARTICLES BEING
Claim 3
Dependent Claim
22 words
The element of claim 1, and in which the catalytic layer has a thickness of from about 100 to about 500 microns.
Claim 4
Dependent Claim
25 words
The element of claim 1, and in which the catalyst is essentially platinum and the binder agent means is an aqueous solution of aluminum nitrate.
Claim 5
Dependent Claim
23 words
The element of claim 1, and in which the catalytic layer is formed on a glass seal which encloses the ceramic coated wire.
Claim 6
Dependent Claim
22 words
The element of claim 4, and in which the catalytic layer has a thickness of from about 100 to about 500 microns.
Claim 7
Dependent Claim
25 words
The element of claim 5, and in which the catalyst is essentially platinum and the binder agent means is an aqueous solution of aluminum nitrate.
Claim 8
Independent Claim
147 words
The method of forming a catalytic coating on a combustion type ceramic coated wire resistance comprising: mixing a powder comprising particles of an oxide selected from the class of oxides consisting of aluminum and beryllium oxide with a solution of a compound of the catalyst, which compound decomposes upon heating to produce the catalyst; heating the resultant mixture so as to evaporate the solution, decompose the compound to the catalyst and coat the oxide powder particles with the catalyst to produce a dried powder of catalytically coated particles; mixing said catalytically coated particles with a liquid binder medium to form a second mixture; applying the second mixture to the resistance element to form a coating thereon; and drying the coating to evaporate the liquid from the second mixture so that the binder medium and the catalytically coated particles of the powder form a porous outer catalytic layer.
Claim 9
Independent Claim
147 words
The method of forming a catalytic coating on a combustion type ceramic coated wire resistance comprising: mixing a powder comprising particles of an oxide selected from the class of oxides consisting of aluminum and beryllium oxide with a solution of a compound of the catalyst, which compound decomposes upon heating to produce the catalyst; heating the resultant mixture so as to evaporate the solution, decompose the compound to the catalyst and coat the oxide powder particles with the catalyst to produce a dried powder of catalytically coated particles; mixing said catalytically coated particles with a liquid binder medium to form a second mixture; applying the second mixture to the resistance element to form a coating thereon; and drying the coating to evaporate the liquid from the second mixture so that the binder medium and the catalytically coated particles of the powder form a porous outer catalytic layer.
Claim 10
Dependent Claim
16 words
The method of claim 7, and in which the compound of the catalyst is chloroplatinic acid.
Claim 11
Dependent Claim
38 words
The method of claim 7, and in which the steps of combining the catalytic compound and oxide particles and heating the resultant mixture are repeated in sequence a plurality of times prior to mixing with the binder medium.
Claim 12
Dependent Claim
25 words
The method of claim 7, and in which the binder medium is an aqueous solution of a nitrate of the same metal as the oxide.
Claim 13
Dependent Claim
34 words
The method of claim 7, and in which the second mixture is repetitively applied to the element so as to form an outer layer of from about 100 to about 500 microns in thickness.
Claim 14
Dependent Claim
31 words
The method of claim 7, and including selecting the size of the oxide particles, prior to their combination with the catalytic compound, to have an average size of about one micron.
Claim 15
Dependent Claim
16 words
The method of claim 12, and in which the compound of the catalyst is chloroplatinic acid.
Claim 16
Dependent Claim
37 words
The method of claim 13 and including the steps of combining the chloroplatinic acid and oxide particles and heating the resultant mixture are repeated in sequence a plurality of times prior to mixing with the binder medium.
Claim 17
Dependent Claim
18 words
The method of claim 14 and in which the binder medium is an aqueous solution of aluminum nitrate.
Claim 18
Dependent Claim
34 words
The method of claim 15 and in which the second mixture is repetitively applied to the element so as to form an outer layer of from about 100 to about 500 microns in thickness.
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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) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |