Patent US4404808A successfully refreshed from Google Patents.
US4404808A
Expired / Lapsed
US
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Cryogenic refrigerator with non-metallic regenerative heat exchanger
Assignee: Azenta Inc
•
Filing: 1981-08-10
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Granted: 1983-09-20
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Expires: 2001-08-10
Abstract
Abstract A refrigerator for operating at cryogenic temperatures which has a heat exchanger comprising a previous regenerative matrix of plastic material, the elements of which behave substantially as isothermal bodies.
Inventors
- 👤 Bruce R. Andeen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:21
CPC Classifications
F; F25; F25B; F25B9/00; F25B9/14; F02; F02G; F02G1/00; F02G1/04; F02G1/043; F02G1/044; F02G1/0445; F02G2250/00; F02G2250/18; F02G2258/00; F02G2258/10; F05; F05C; F05C2225/00; F05C2225/08; F25B2309/00; F25B2309/003; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/888; Y10S505/894; Y10S505/895
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
23 words
A regenerative heat exchanger for operating at cryogenic temperatures characterized by its regenerative heat exchanging element being a pervious matrix of plastic material.
Claim 2
Dependent Claim
23 words
A regenerative heat exchanger for operating at cryogenic temperatures characterized by its regenerative heat exchanging element being a pervious matrix of plastic material.
Claim 3
Dependent Claim
30 words
A regenerative heat exchanger for operating at cryogenic temperatures characterized by its regenerative heat exchanging element comprising a pervious displacer containing non-metallic matrix elements which behave substantially as isothermal bodies.
Claim 4
Dependent Claim
30 words
A regenerative heat exchanger for operating at cryogenic temperatures characterized by its regenerative heat exchanging element comprising a pervious displacer containing non-metallic matrix elements which behave substantially as isothermal bodies.
Claim 5
Dependent Claim
19 words
The heat exchanger of claims 1 and 2 in which the matrix is a particulate mass of nylon beads.
Claim 6
Dependent Claim
19 words
The heat exchanger of claims 1 and 2 in which the matrix is a particulate mass of polypropylene beads.
Claim 7
Dependent Claim
20 words
The heat exchanger of claims 1 and 2 in which the matrix is a stack of layers of plastic mesh.
Claim 8
Dependent Claim
18 words
The heat exchanger of claims 1 and 2 in which the matrix is a mass of plastic wool.
Claim 9
Dependent Claim
21 words
A refrigerator for operating at cryogenic temperatures characterized by having a heat exchanger comprising a pervious regenerative matrix of plastic material.
Claim 10
Dependent Claim
21 words
A refrigerator for operating at cryogenic temperatures characterized by having a heat exchanger comprising a pervious regenerative matrix of plastic material.
Claim 11
Dependent Claim
27 words
The refrigerator of claim 7 in which the matrix is a particulate mass of nylon beads with dimensions ranging from about 0.006 inch to about 0.012 inch.
Claim 12
Dependent Claim
27 words
The refrigerator of claim 7 in which the matrix is a particulate mass of polypropylene beads with dimensions ranging from about 0.006 inch to about 0.014 inch.
Claim 13
Dependent Claim
23 words
The refrigerator of claim 7 in which the matrix is a stack of layers of nylon mesh having 210 filaments per linear inch.
Claim 14
Dependent Claim
25 words
The refrigerator of claim 7 in which the matrix is a stack of layers of nylon mesh having a filament diameter of about 0.0019 inch.
Claim 15
Dependent Claim
55 words
A refrigerator for operating at cryogenic temperatures comprising a compressor, a reciprocating displacer within a cold finger, the displacer being driven in reciprocating motion by the compressor through the medium of a compressable gas and a regenerative heat exchanger in the displacer in communication with the compressed gas comprising a pervious matrix of plastic material.
Claim 16
Dependent Claim
55 words
A refrigerator for operating at cryogenic temperatures comprising a compressor, a reciprocating displacer within a cold finger, the displacer being driven in reciprocating motion by the compressor through the medium of a compressable gas and a regenerative heat exchanger in the displacer in communication with the compressed gas comprising a pervious matrix of plastic material.
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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) | 1986-09-19 | 1987-03-21 | 1987-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-19 | 1991-03-21 | 1991-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-19 | 1995-03-21 | 1995-09-20 | $7700.00 | Window Closed / Lapsed |