US3771960A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas analyzer
Assignee: Ambac Industries Inc
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Filing: 1971-07-28
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Granted: 1973-11-13
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Expires: 1991-07-28
Abstract
Abstract A catalytic combustion Wheatstone bridge type gas analyzer produces a mixture of gas and air by gaseous diffusion of the gas and air separately through porous walls into a reaction chamber to form the mixture, which contacts the catalytic element in the bridge circuit. The porosity of the walls is selected to permit gaseous diffusion transfer while preventing gaseous transfer into the reaction chamber by convection. The relative surface areas for diffusion of the gas sample and air are selected to provide a predetermined dilution ratio for the sample.
Inventors
- 👤 Kim Y Ho
- 👤 J Pattison
- 👤 K Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:53
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/14; G01N27/16; Y; Y10; Y10S; Y10S48/00; Y10S48/05; Y10T; Y10T436/00; Y10T436/20; Y10T436/204998; Y10T436/205831; Y10T436/25; Y10T436/25375; Y10T436/255; Y10T436/25875
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
47 words
The combination of claim 1 and including means for applying the gas to be analyzed to the porous wall forming means first portion at a velocity such that the pressure differential across the porous wall forming means is insufficient to initiate substantial gaseous transfer therethrough by convection.
Claim 2
Dependent Claim
34 words
The combination of claim 1 and including means for applying the gas to be analyzed to the porous wall forming means first portion at substantially the same pressure as exists within the reaction chamber.
Claim 3
Dependent Claim
32 words
The combination of claim 1 and in which the two wall forming means portions comprise a unitary structure which is divided into the first and the second portions by said sealing means.
Claim 4
Dependent Claim
170 words
In a gas analyzer of the Wheatstone bridge type, the combination of: an analyzer body; a hollow inlet chamber having a gas inlet at one end, and exhaust means remote therefrom; means attaching the inlet chamber to the body; a reaction chamber; porous wall forming means on said reaction chamber, said wall forming means having a porosity such as to inhibit gaseous transfer therethrough by convection while permitting gaseous diffusion transfer therethrough; an active element mounted within said reaction chamber; means forming a peripheral seal about said reaction chamber so that a first portion of the reaction chamber has porous walls in communication with the inlet chamber gas inlet and sealed from a second portion of the reaction chamber; means for flowing a gas to be analyzed through the gas inlet so that the gas pressure differential across the first porous wall portion is insufficient to initiate transfer of the gas therethrough by convection; and communication means for communicating a second gas into said reaction chamber through said second portion.
Claim 5
Dependent Claim
113 words
The combination of claim 5 and including an aperture in the analyzer body, the analyzer body having a hollow interior into which the aperture opens; an open end in the hollow inlet chamber, the inlet chamber being attached to the analyzer body so that the hollow open end closes the analyzer body aperture; means for attaching the reaction chamber to the analyzer body so that the second portion of the reaction chamber is in communication with the interior of the analyzer body by means of the aperture; and reaction chamber second portion porous wall means included in said communication means and disposed between the interior of the reaction chamber and the analyzer body.
Claim 6
Dependent Claim
45 words
The combination of claim 6, and in which the means for applying gas through the inlet chamber includes baffle means within said inlet chamber operable to shield the reaction chamber porous walls from a direct flow of gas passing through the inlet chamber gas inlet.
Claim 7
Dependent Claim
137 words
The combination of claim 7 and including a gas probe attached to the inlet chamber, said gas probe having a first tubular probe, of a first diameter and first length, extending outwardly from the inlet chamber; a second tubular probe of a second diameter and second length, said second diameter and second length being less than the first diameter and first length, respectively; means for disposing the second probe within the first probe so as to provide a gas passage from the first probe through the second probe to the inlet chamber gas inlet, said second probe shielding said inlet chamber gas inlet from direct communication with the first probe adjacent the inlet chamber; and at least one drain aperture in the first probe within the portion thereof which is coincident in length with the second probe.
Claim 8
Dependent Claim
62 words
The combination of claim 5 and including means for connecting the reaction chamber to the analyzer body so that the reaction chamber is contained within the inlet chamber; and reaction chamber second portion porous wall means included in said communication means, said communication means extending between the interior of the reaction chamber and the exterior of the analyzer through the analyzer body.
Claim 9
Dependent Claim
44 words
The combination of claim 9, and in which the means for applying gas through the inlet chamber includes baffle means within said inlet chamber operable to shield the reaction chamber porous walls from direct flow of gas passing through the inlet chamber gas inlet.
Claim 10
Dependent Claim
137 words
The combination of claim 10 and including a gas probe attached to the inlet chamber, said gas probe having a first tubular probe, of a first diameter and first length, extending outwardly from the inlet chamber; a second tubular probe of a second diameter and second lengtH, said second diameter and second length being less than the first diameter and first length, respectively; means for disposing the second probe within the first probe so as to provide a gas passage from the first probe through the second probe to the inlet chamber gas inlet, said second probe shielding said inlet chamber gas inlet from direct communication with the first probe adjacent the inlet chamber; and at least one drain aperture in the first probe within the portion thereof which is coincident in length with the second probe.
Claim 11
Independent Claim
158 words
The method of analyzing a gas sample by combustion at a catalytic element connected to analyzing means comprising, applying the gas sample to a porous barrier preselected with respect to porosity to permit diffusion transfer of the gas therethrough while inhibiting transfer therethrough by convection and preselected with respect to surface area as a function of the relative proportion of gas from the sample to be contained in the mixture, applying air to a second porous barrier preselected with respect to porosity to permit diffusion transfer of air therethrough while inhibiting transfer therethrough by convection and preselected with regard to surface area as a function of the relative proportion of air required to insure the resultant reaction rate at the catalytic element is not limited by the rate of diffusion of oxygen in the air to the catalytic element, and contacting the catalytic element with a mixture of gas and air which have diffused through the porous barriers.
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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) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |