Patent US4204336A successfully refreshed from Google Patents.
US4204336A
Expired / Lapsed
US
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Microwave freeze drying method and apparatus
Assignee: Nestec SA
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Filing: 1978-04-21
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Granted: 1980-05-27
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Expires: 1998-04-21
Abstract
Abstract A process and an apparatus for freeze-drying by means of microwaves, in which the product to be dried is placed on a support composed of a material which is transparent to microwave energy, covered with a layer of material which conducts electricity.
Inventors
- 👤 Toai Le Viet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:46
CPC Classifications
F; F26; F26B; F26B5/00; F26B5/04; F26B5/06; A; A23; A23F; A23F5/00; A23F5/24; A23F5/28; A23F5/32; F26B5/048
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
62 words
In the freeze-drying of a product which employs apparatus including a source of microwave energy and a support disposed below said source and upon which said product is received, the steps of providing said support as a two-layer component, absorbing microwave energy and conducting electricity in the upper one of said layers, and transmitting energy through the lower one of said layers.
Claim 2
Dependent Claim
62 words
In the freeze-drying of a product which employs apparatus including a source of microwave energy and a support disposed below said source and upon which said product is received, the steps of providing said support as a two-layer component, absorbing microwave energy and conducting electricity in the upper one of said layers, and transmitting energy through the lower one of said layers.
Claim 3
Independent Claim
77 words
An apparatus for freeze-drying a product by subjecting it to microwave energy, said apparatus comprising a vacuum chamber, a microwave applicator, and a conveyor belt for receiving the product and transporting it through said chamber past said applicator, the belt having a product receiving surface layer of a material which conducts electricity and comprising carbon fibers embedded in an insulating material, with the belt structure underlying said layer being capable of transmitting microwave energy and comprising polytetrafluorethylene.
Claim 4
Independent Claim
77 words
An apparatus for freeze-drying a product by subjecting it to microwave energy, said apparatus comprising a vacuum chamber, a microwave applicator, and a conveyor belt for receiving the product and transporting it through said chamber past said applicator, the belt having a product receiving surface layer of a material which conducts electricity and comprising carbon fibers embedded in an insulating material, with the belt structure underlying said layer being capable of transmitting microwave energy and comprising polytetrafluorethylene.
Claim 5
Dependent Claim
15 words
The apparatus of claim 2 in which said product receiving layer further comprises glass fibers.
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) | 1983-05-27 | 1983-11-26 | 1984-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-27 | 1987-11-26 | 1988-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-27 | 1991-11-26 | 1992-05-27 | $7700.00 | Window Closed / Lapsed |