Patent US5401470A successfully refreshed from Google Patents.
US5401470A
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Combustible gas sensor
Assignee: MSA Safety Inc
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Filing: 1992-04-24
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Granted: 1995-03-28
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Expires: 2012-04-24
Abstract
Abstract A matched catalytically inactive compensator for use in a combustible gas sensor is made from a catalytically active detector. The catalytically active detector is exposed to a gas phase catalytic inhibitor such as hexamethyldisiloxane to completely destroy its catalytic ability thereby forming a compensator which has very similar chemical and physical properties to the untreated detectors.
Inventors
- 👤 Albert A. Poli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:26
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/14; G01N27/16
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
74 words
In a sensor for detecting a combustible gas comprising a catalytically active detector and a catalytically inactive compensator, the improvement comprising making the sensor from a plurality of chemically and physically similar catalytically active elements one of said elements being the catalytically active detector and creating the catalytically inactive compensator by taking another of the chemically and physically similar catalytically active elements and rendering it catalytically inactive by exposure to a gas-phase catalytic poison.
Claim 2
Dependent Claim
74 words
In a sensor for detecting a combustible gas comprising a catalytically active detector and a catalytically inactive compensator, the improvement comprising making the sensor from a plurality of chemically and physically similar catalytically active elements one of said elements being the catalytically active detector and creating the catalytically inactive compensator by taking another of the chemically and physically similar catalytically active elements and rendering it catalytically inactive by exposure to a gas-phase catalytic poison.
Claim 3
Dependent Claim
30 words
The sensor as described in claim 1 wherein the gas-phase catalytic poison used to transform one of the catalytically active elements into the catalytically inactive compensator is a silicone-based compound.
Claim 4
Dependent Claim
40 words
The sensor as described in claim 2 wherein the silicone-based compound has a vapor pressure sufficient to enable the compound to diffuse into one of the catalytically active elements and render it catalytically inactive thereby forming the catalytically inactive compensator.
Claim 5
Dependent Claim
15 words
The sensor as described in claim 3 wherein the silicone-based compound is hexamethyldisiloxane or decamethylcyclpentasiloxane.
Claim 6
Dependent Claim
33 words
The sensor as described in claim 1 wherein the gas-phase catalytic poison used to transform one of the catalytically active elements into the catalytically inactive compensator is hydrogen sulfide or a phosphorous-based compound.
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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) | 1998-03-27 | 1998-09-26 | 1999-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-03-27 | 2002-09-26 | 2003-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-03-27 | 2006-09-26 | 2007-03-28 | $7700.00 | Window Closed / Lapsed |