US3790348A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for determining the carbon monoxide, methane and total hydrocarbons content in air
Assignee: MSA Safety Inc
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Filing: 1972-03-22
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Granted: 1974-02-05
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Expires: 1992-03-22
Abstract
Abstract An air sample to be analyzed for carbon monoxide and methane is delivered to a chromatograph column that is connected by a reactor with a hydrogen flame ionization detector. The reactor converts carbon monoxide in the sample into methane. The amount of carbon monoxide and methane in the sample is determined by measuring the electrical conductivity of the detector. To measure total hydrocarbons in the impure air being sampled, a stream of the sample air is delivered to a conduit communicating with the detector. When total hydrocarbons are not being detected, a stream of pure air is delivered to the conduit continuously to establish a reference point for the analyses.
Inventors
- 👤 C Bossart
- 👤 A Poli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:47
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/005; G01N30/00; G01N30/02; G01N30/84; G01N2030/022; G01N2030/025; G01N2030/8405; G01N30/62; G01N30/64; G01N30/68; Y; Y10; Y10T; Y10T436/00; Y10T436/20; Y10T436/204998; Y10T436/205831; Y10T436/21; Y10T436/214; Y10T436/218
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
42 words
Apparatus according to claim 1, in which said conduit includes an air restrictor and an outlet to atmosphere at the upstream side of the restrictor, and a back pressure regulator connected with said outlet to maintain a constant pressure in said conduit.
Claim 2
Dependent Claim
44 words
Apparatus according to claim 1, in which said first means include a tube filled with said air sample, conduit means for continuously delivering a carrier gas to said column and normally by-passing said tube, and means for connecting said tube into said conduit means.
Claim 3
Dependent Claim
26 words
Apparatus according to claim 3, in which said fourth means normally delivers the sample air to said tube, and said tube normally is vented to atmosphere.
Claim 4
Dependent Claim
52 words
Apparatus according to claim 1, in which said third means includes a valve provided with a passage connecting a source of pure air with said conduit, and said fourth means likewise includes said valve switched to a position in which a valve passage connects a source of sample air with the conduit.
Claim 5
Dependent Claim
75 words
Apparatus according to claim 5, in which said first means include a tube filled with said sample air, conduit means for continuously delivering a carrier gas to said column and normally by-passing said tube, and means for connecting said tube into said conduit means, the apparatus including a sample line connected with said tube and connected by said valve with said source of sample air while the valve is connecting pure air with said conduit.
Claim 6
Dependent Claim
38 words
Apparatus according to claim 6, in which said valve is provided with a passage for connecting said source of pure air with said sample line while the valve is connecting said source of sample air with said conduit.
Claim 7
Dependent Claim
34 words
Apparatus according to claim 6, in which said conduit means include a second valve, and said connecting means likewise include the second valve switcHed to a position connecting said tube with said conduit means.
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) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |