US4306419A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brushless DC motor driven cryogenic refrigeration system
Assignee: JPMorgan Chase Bank NA
•
Filing: 1980-10-14
•
Granted: 1981-12-22
•
Expires: 2000-10-14
Abstract
Abstract A portable cryogenic helium-filled refrigeration system includes a cold finger evaporator, a compressor connected to the cold finger, a brushless DC motor connected to drive the compressor, and an electronic circuit for switching the stator-armature winding currents of the motor. The motor and compressor and the electronic circuit are all enclosed within a common housing which is charged with helium gas refrigerant under pressure.
Inventors
- 👤 Myron Schwartz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 00:27
CPC Classifications
H; H02; H02K; H02K9/00; H02K9/10; H02K9/12; F; F25; F25B; F25B9/00; F25B9/14; H02K7/00; H02K7/14; F25B2309/00; F25B2309/003
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
103 words
In combination, a portable cryogenic refrigeration system comprising a helium-filled refrigerant system including a cold finger arranged to be immersed in a container to be refrigerated, a compressor connected through a refrigerant line to said cold finger for compressing the helium, a brushless DC motor connected to drive said compressor, said motor and said compressor being housed in a common housing, an electronic circuit for switching the stator-armature winding currents of said motor in synchronism with the rotation of the motor rotor, said electronic circuit being enclosed within said common housing, and the entire interior of said common housing being charged with helium.
Claim 2
Dependent Claim
103 words
In combination, a portable cryogenic refrigeration system comprising a helium-filled refrigerant system including a cold finger arranged to be immersed in a container to be refrigerated, a compressor connected through a refrigerant line to said cold finger for compressing the helium, a brushless DC motor connected to drive said compressor, said motor and said compressor being housed in a common housing, an electronic circuit for switching the stator-armature winding currents of said motor in synchronism with the rotation of the motor rotor, said electronic circuit being enclosed within said common housing, and the entire interior of said common housing being charged with helium.
Claim 3
Dependent Claim
15 words
A system as claimed in claim 1 wherein said electronic circuit is a printed circuit.
Claim 4
Dependent Claim
16 words
A system as claimed in claim 2 wherein said printed circuit is a hybrid printed circuit.
Claim 5
Dependent Claim
18 words
A system as claimed in claim 2 wherein said circuit is open to the interior of said housing.
References Cited (Backward Citations)
US3341724A
Cited
US3423948A
Cited
US3774405A
Cited
SU614501A1
Cited
US3853437A
Cited
US4044567A
Cited
US4220879A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-12-21 | 1985-06-22 | 1985-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-21 | 1989-06-22 | 1989-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-21 | 1993-06-22 | 1993-12-22 | $7700.00 | Window Closed / Lapsed |