US3567117A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ice nuclei formation
Assignee: Dewey Electronics Corp
•
Filing: 1969-08-29
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Granted: 1971-03-02
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Expires: 1989-08-29
Abstract
Abstract A method of making snow by controlling the size and life of ice nuclei generated in a snow-making machine. Ice nuclei are generated by homogeneous nucleation in a tunnellike housing through injection of propane or other refrigerant into a stream of moist air. The relative humidity about the ice nuclei stream is controlled relative to the temperature and humidity of the atmosphere to prevent or inhibit evaporation of the ice nuclei for such time as to ensure statistically effective mixing with adjacent liquid phase water droplets which are supercooled by the air mass. The ice nuclei formed infect the water droplets and they release their latent heat to the air to form snowlike particles.
Inventors
- 👤 William E C Eustis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:57
CPC Classifications
F; F25; F25C; F25C3/00; F25C3/04; F25C1/00; F25C2303/00; F25C2303/046; F25C2303/048; F25C2303/0481
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
38 words
The method of claim 1 wherein the ice nuclei are discharged from the separate zone in a nuclei stream and the nuclei are preserved by controlling the relative humidity between 70 and 95 percent within the nuclei stream.
Claim 2
Dependent Claim
64 words
The method of claim 1 which includes: forming the ice nuclei by injecting a refrigerant into a moist stream of cold air the refrigerant adapted to lower the temperature of the airstream to less than -40* C. and wherein the relative humidity of the airstream is controlled to provide sufficient humidity within the ice-nuclei stream formed to inhibit burning off of the ice nuclei.
Claim 3
Dependent Claim
37 words
The method of claim 1 wherein the size of the ice nuclei formed are between 125 and 250 microns and the refrigerant is selected from the group consisting of propane, methane, freon, carbon dioxide and sulfur dioxide.
Claim 4
Dependent Claim
23 words
The method of claim 4 wherein the refrigerant is liquid propane which incurs a phase change from a liquid to a gaseous state.
Claim 5
Dependent Claim
32 words
The method of claim 1 wherein the ice nuclei are formed by the adiabatic expansion of compressed air and the ice nuclei are discharged from the one zone in a nuclei stream.
Claim 6
Dependent Claim
24 words
The method of claim 6 which includes controlling the moisture content of the compressed air to provide the proper humidity within the nuclei stream.
Claim 7
Dependent Claim
78 words
The method of claim 1 which includes: a. breaking water into droplets at a temperature of greater than 0* C.; b. supercooling the droplets so formed to less than 0* C. by flowing a mass of ambient air about the droplets; c. discharging the ice nuclei formed from the zone in a separate nuclei stream; d. preserving the ice nuclei formed by controlling the relative humidity about the ice-nuclei stream; and e. subsequently infecting the supercooled water droplets.
Claim 8
Dependent Claim
14 words
The method of claim 7 wherein the ice nuclei are formed by homogeneous nucleation.
References Cited (Backward Citations)
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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) | 1974-03-01 | 1974-08-31 | 1975-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-01 | 1978-08-31 | 1979-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-01 | 1982-08-31 | 1983-03-02 | $7700.00 | Window Closed / Lapsed |