US3768272A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct contact food freezer
Assignee: Individual
•
Filing: 1970-06-17
•
Granted: 1973-10-30
•
Expires: 1990-06-17
Abstract
Abstract This invention provides a direct contact freezing device using a low boiling point, inert refrigerant in a stream having portions at different velocities for the direct contact freezing of comestibles without clumping of the particles or icing of the freezer.
Inventors
- 👤 L Barrett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:22
CPC Classifications
F; F25; F25D; F25D9/00; F25D9/005; A; A23; A23B; A23B2/00; A23B2/80; A23B2/803; A23B2/8033
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
88 words
A method of freezing food portions in a direct contact food freezer comprising the steps of introducing said food portions into a freezing compartment, contacting said food portions with a boiling liquid refrigerant, having a boiling point at 1 atmosphere higher than -50* F. to freeze said food portions, discharging said food portions from said freezer, receiving said food portions in a substantially impervious container and recovering the gaseous refrigerant from said container to said food freezer, said container being in releasable sealed relationship with said food freezer.
Claim 2
Independent Claim
88 words
A method of freezing food portions in a direct contact food freezer comprising the steps of introducing said food portions into a freezing compartment, contacting said food portions with a boiling liquid refrigerant, having a boiling point at 1 atmosphere higher than -50* F. to freeze said food portions, discharging said food portions from said freezer, receiving said food portions in a substantially impervious container and recovering the gaseous refrigerant from said container to said food freezer, said container being in releasable sealed relationship with said food freezer.
Claim 3
Dependent Claim
24 words
The method of direct contact food freezing as specified in claim 1 in which the said receiving container is a substantially impervious pliable container.
Claim 4
Dependent Claim
36 words
The method of direct contact food freezing as specified in claim 1 in which the said container has a smaller internal volume when containing no food portions than when at least partially filled with food portions.
Claim 5
Dependent Claim
20 words
The method as specified in claim 1 including the additional step of returning said recovered gaseous refrigerant to said freezer.
Claim 6
Dependent Claim
21 words
The method as specified in claim 1 including the additional step of purifying said recovered gaseous refrigerant subsequent to said recovering.
Claim 7
Dependent Claim
33 words
The method as specified in claim 1 wherein said recovering of said gaseous refrigerant is by withdrawing the gaseous refrigerant from said container at a location below the horizontal centerline of said container.
Claim 8
Dependent Claim
39 words
The method as specified in claim 6 including the additional step of admitting to said container at a location above said horizontal centerline a gas having a lesSer density than said gaseous refrigeration, while simultaneously withdrawing said gaseous refrigerant.
Claim 9
Dependent Claim
33 words
The method as specified in claim 11 wherein said discharging is into a substantially impervious sealed food storage zone and including the additional step of recovering excess gaseous refrigerant from said storage zone.
Claim 10
Dependent Claim
61 words
The method as specified in claim 8 wherein said recovering of said excess gaseous refrigerant is by withdrawing said excess gaseous refrigerant from said storage zone at a location below the horizontal centerline of said container while simultaneously admitting to said storage zone at a location above said horizontal centerline a gas having a lesser density than said excess gaseous refrigerant.
Claim 11
Dependent Claim
21 words
The method as specified in claim 8 including the additional step of purifying the excess gaseous refrigerant subsequent to said recovering.
Claim 12
Independent Claim
103 words
A method of freezing food in a direct contact food freezer comprising the steps of: introducing said food into a freezing compartment by hydraulic sealing means including a liquid barometric seal; subsequent to said introducing contacting said food with a liquid refrigerant having a boiling point at one atmosphere higher than -50* F to freeze said food; simultaneously with said introducing and said contacting maintaining a separation between said liquid refrigerant and said hydraulic sealing means; and discharging said food from said freezing compartment through an exit adapted to seal at least a major portion of the gasified refrigerant within said food freezer.
Claim 13
Independent Claim
103 words
A method of freezing food in a direct contact food freezer comprising the steps of: introducing said food into a freezing compartment by hydraulic sealing means including a liquid barometric seal; subsequent to said introducing contacting said food with a liquid refrigerant having a boiling point at one atmosphere higher than -50* F to freeze said food; simultaneously with said introducing and said contacting maintaining a separation between said liquid refrigerant and said hydraulic sealing means; and discharging said food from said freezing compartment through an exit adapted to seal at least a major portion of the gasified refrigerant within said food freezer.
Claim 14
Dependent Claim
60 words
A method of freezing food in a direct contact food freezer specified in claim 11 in which the said food includes food portions in liquid; the said hydraulic sealing means includes a conveying liquid in an enclosed flow path and including the additional step of removing said conveying liquid from said direct contact food freezer through a second barometric seal.
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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) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |