US3856204A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas emitting device
Assignee: Ambac Industries Inc
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Filing: 1973-03-12
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Granted: 1974-12-24
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Expires: 1993-03-12
Abstract
Abstract A device for emitting a gas at a constant rate into a moving fluid medium to produce an accurately known concentration of the gas in the medium. The gas is held in a small cylinder under pressure in equilibrium with its liquid phase or solely in its gaseous phase, and permeates through a silicone material filling an accurately dimensioned passage through one end of the cylinder. Permeation rates may be selected from a wide range by varying the dimensions of the passage, and the device has a relatively low sensitivity to temperature variations.
Inventors
- 👤 R Chand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:48
CPC Classifications
G; G01; G01N; G01N1/00; G01N1/28; G05; G05D; G05D11/00; G05D11/02; G05D11/035
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
20 words
A device as set forth in claim 1, wherein said quantity of permeable polymeric silicone material is a dimethyl polysiloxane.
Claim 2
Dependent Claim
22 words
A device as set forth in claim 1, wherein said substance is held by said sealed vessel partially in the liquid phase.
Claim 3
Dependent Claim
18 words
A device as set forth in claim 3, wherein said permeable polymeric silicone material is a dimethyl polysiloxane.
Claim 4
Independent Claim
97 words
A device for emitting a substance at a predetermined rate, comprising: a sealed vessel for holding said substance under pressure, said vessel being impermeable to said substance and having an exit passage for emission of said substance; and a quantity of permeable polymeric plastic material completely blocking said passage, said material having a permeability which decreases with increasing temperature and constant pressure in said vessel, whereby said substance permeates through said material blocking said passage and is emitted from said vessel at the predetermined rate, and said device has a characteristically low overall sensitivity to temperature variations.
Claim 5
Dependent Claim
17 words
A device as set forth in claim 5, wherein said permeable polymeric plastic is a silicone polymer.
Claim 6
Dependent Claim
16 words
A device as set forth in claim 6, wherein said silicone polymer is a dimethyl polysiloxane.
Claim 7
Dependent Claim
22 words
A device as set forth in claim 6, wherein said substance is held by said sealed vessel partially in the liquid phase.
Claim 8
Dependent Claim
50 words
A device as set forth in claim 5, wherein said permeable polymeric plastic is a silicone polymer and said substance is held by said sealed vessel partially in the liquid phase, said device further including temperature control means to maintain said vessel and said substance at a substantially constant temperature.
Claim 9
Dependent Claim
14 words
A device as set forth in claim 9, further including removable vessel sealing means.
Claim 10
Dependent Claim
42 words
A device as set forth in claim 5, wherein said substance is selected from the group consisting of sulfur dioxide, nitrogen dioxide, hydrogen sulfide, ammonia, chlorine, bromine, hydrogen fluoride, propane, propylene, methyl mercaptan, ethyl oxide, n-butane, carbon tetrachloride, formaldehyde, acetaldehyde, and water.
Claim 11
Independent Claim
141 words
A device for emitting a substance at a predetermined rate into a moving fluid stream to produce a desired concentration of said substance in the stream, said device comprising: a sealed vessel for holding said substance under pressure, said vessel being impermeable to said substance and having a passage through which said substance is emitted into the moving fluid stream; a quantity of a permeable silicone polymeric material completely filling Said passage and bonded to the walls thereof, said material having a permeability which decreases with increasing temperature and constant pressure in said vessel; connection means for connecting said device to the moving fluid stream, whereby said substance permeates through said silicone material at the predetermined rate and is emitted into the moving fluid stream through said connection means, and said device has a characteristically low overall sensitivity to temperature variations.
Claim 12
Dependent Claim
26 words
A device as set forth in claim 12, further including sealing means removably attached to said vessel to allow filling and refilling thereof with said substance.
Claim 13
Dependent Claim
27 words
A device as set forth in claim 13, wherein: said vessel is a hollow cylinder; and said passage is a tube through one end of said cylinder.
Claim 14
Dependent Claim
27 words
A device as set forth in claim 14, wherein said connection means includes a T-shaped pipe fitting connecting said cylinder to a line enclosing the fluid stream.
Claim 15
Dependent Claim
42 words
A device as set forth in claim 12, wherein said substance is selected from the group consisting of sulfur dioxide, nitrogen dioxide, hydrogen sulfide, ammonia, chlorine, bromine, hydrogen fluoride, propane, propylene, methyl mercaptan, ethyl oxide, n-butane, carbon tetrachloride, formaldehyde, acetaldehyde, and water.
Claim 16
Dependent Claim
28 words
A device as set forth in claim 12, wherein said substance is held by said sealed vessel partially in the liquid phase in equilibrium with the gaseous phase.
Claim 17
Dependent Claim
22 words
A device as set forth in claim 12, wherein said substance is held by said sealed vessel solely in the gaseous phase.
Claim 18
Dependent Claim
37 words
A device as set forth in claim 12, further including temperature control means for maintaining said sealed vessel and said substance at a substantially constant temperature, and thereby maintaining a constant rate of emission of said substance.
Claim 19
Dependent Claim
26 words
A device as set forth in claim 19, further including sealing means removably attached to said vessel to allow filling and refilling thereof with said substance.
Claim 20
Dependent Claim
27 words
A device as set forth in claim 20, wherein: said vessel is a hollow cylinder; and said passage is a tube through one end of said cylinder.
Claim 21
Dependent Claim
122 words
For use with apparatus for the analysis of fluid mixtures, a device for generating a calibration mixture with a predetermined concentration of a substance, said device comprising: a vessel for holding said substance under pressure, said vessel being impermeable to said substance and having a passage through which said substance is emitted into a moving stream of an inert fluid medium; a body of a permeable silicone polymeric material completely filling said passage and bonded to the walls thereof to limit emission of said substance to a constant rate for a constant temperature, said material having a permeability which decreases with increasing temperature and constant pressure in said vessel, thereby providing for said device a characteristically low overall sensitivity to temperature variations.
Claim 22
Dependent Claim
26 words
A device as set forth in claim 22, wherein: said vessel is a hollow cylinder; and said passage is located at one end of said cylinder.
Claim 23
Dependent Claim
29 words
A device as set forth in claim 23, wherein said connection means includes a T-shaped pipe fitting connecting said cylinder to a pipe enclosing the moving stream of fluid.
Claim 24
Dependent Claim
42 words
A device as set forth in claim 22, wherein said substance is selected from the group consisting of sulfur dioxide, nitrogen dioxide, hydrogen sulfide, ammonia, chlorine, bromine, hydrogen fluoride, propane, propylene, methyl mercaptan, ethyl oxide, n-butane, carbon tetrachloride, formaldehyde, acetaldehyde, and water.
Claim 25
Dependent Claim
28 words
A device as set forth in claim 22, wherein said substance is held by said sealed vessel partially in the liquid state in equilibrium with the gaseous phase.
Claim 26
Dependent Claim
22 words
A device as set forth in claim 22, wherein said substance is held by said sealed vessel solely in the gaseous phase.
Claim 27
Dependent Claim
26 words
A device as set forth in claim 22, further including tempeRature control means for maintaining said sealed vessel and said gaseous substance at a constant temperature.
Claim 28
Dependent Claim
22 words
A device as set forth in claim 1, wherein said substance is held by said sealed vessel entirely in the gaseous phase.
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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |