US4184074A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nondispersive infrared gas analysis device
Assignee: Individual
•
Filing: 1978-07-06
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Granted: 1980-01-15
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Expires: 1998-07-06
Abstract
Abstract A body has two bores defining two cuvette chambers, one for holding a comparison gas and the other for holding a gas to be analyzed by comparison with the first. An infrared (IR) source at one end of the body provides in-phase radiation into the two cuvettes. At the other end is a window, a selective filter, a reception chamber for each cuvette, and an absorption chamber. The reception chambers are coupled to a device for producing a signal representing the difference in radiation reaching the reception chambers. The reception and absorption chambers are separated by a low reflectance window and the absorption chamber contains an IR absorbing body of glass, polymethacrylate or the like with concentric grooves.
Inventors
- 👤 Otto H. Blunck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:13
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/35; G01N21/37; G01N21/59; G01N21/61
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
203 words
A nondispersive infrared gas analysis device comprising first and second gas-containing cuvettes adapted, respectively, to contain a gas to be analyzed and a comparison gas, said cuvettes having radiation transparent means at both ends thereof; a source of radiation coupled to said transparent means at one end of the cuvettes to pass isophase radiation thereto; a detector unit at the other end of said cuvettes to receive radiation emanating from said cuvettes for producing a differential signal representative of differences in radiation emanating from said cuvettes, said detector unit comprising: a body; means defining first and second reception chambers in said body adapted to receive radiation from said first and second cuvettes, respectively; filter means between said cuvettes and said chambers for selectively passing into said chambers radiation at a predetermined wavelength; an input window covering an end of said chambers adjacent said filter means; a second window covering the other end of said chambers, said second window being formed to be substantially free of reflection; means defining an infrared absorption chamber hermetically sealed from said reception chambers by said second window for absorbing infrared energy passing through said reception chambers; and means coupled to said reception chambers for producing the differential signals.
Claim 2
Dependent Claim
203 words
A nondispersive infrared gas analysis device comprising first and second gas-containing cuvettes adapted, respectively, to contain a gas to be analyzed and a comparison gas, said cuvettes having radiation transparent means at both ends thereof; a source of radiation coupled to said transparent means at one end of the cuvettes to pass isophase radiation thereto; a detector unit at the other end of said cuvettes to receive radiation emanating from said cuvettes for producing a differential signal representative of differences in radiation emanating from said cuvettes, said detector unit comprising: a body; means defining first and second reception chambers in said body adapted to receive radiation from said first and second cuvettes, respectively; filter means between said cuvettes and said chambers for selectively passing into said chambers radiation at a predetermined wavelength; an input window covering an end of said chambers adjacent said filter means; a second window covering the other end of said chambers, said second window being formed to be substantially free of reflection; means defining an infrared absorption chamber hermetically sealed from said reception chambers by said second window for absorbing infrared energy passing through said reception chambers; and means coupled to said reception chambers for producing the differential signals.
Claim 3
Dependent Claim
44 words
A device according to claim 1 wherein each of said reception chambers has an axis of symmetry in the direction of travel of the radiation, and wherein each of said reception chambers has a square cross section in planes containing the axis of symmetry.
Claim 4
Dependent Claim
76 words
A device according to claim 1 wherein said means defining an absorption chamber includes a metallic body having a recess to define said chamber, and an infrared absorbing body in said recess, said body being formed as a disc having a plurality of concentric grooves in one face thereof, said grooves being formed to define a sawtooth pattern in transverse selection with at least one edge of the sawtooth extending parallel with the direction of radiation.
Claim 5
Dependent Claim
13 words
A device according to claim 3 wherein said infrared absorbing body is glass.
Claim 6
Dependent Claim
13 words
A device according to claim 3 wherein said infrared absorbing body is polymethacrylate.
Claim 7
Dependent Claim
42 words
A device according to claim 1 wherein said means defining an absorption chamber includes a metallic casing having a recess to define said chamber, and an infrared absorbing body in said recess, said absorbing body being made from glass or transparent polymethacrylate.
References Cited (Backward Citations)
US2844729A
Cited
US3725702A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-01-14 | 1983-07-16 | 1984-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-14 | 1987-07-16 | 1988-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-14 | 1991-07-16 | 1992-01-15 | $7700.00 | Window Closed / Lapsed |