US3909574A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave tunnel-ovens
Assignee: Kreis AG
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Filing: 1974-03-28
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Granted: 1975-09-30
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Expires: 1994-03-28
Abstract
Abstract This invention relates to microwave tunnel ovens of the kind having absorption sections enclosed by a metal casing which form continuations of a central passage of said oven at both the inlet and outlet ends. The invention consists in that said absorption sections contain a plurality of load members, each of which is made of a microwave-absorbent material and is arranged between said casing and said central opening the said load members being spaced from one another. These load members may be individual ferrite rods or tubes or may consist of individual portions of a plastics material helical tube containing a liquid and arranged around the central passage.
Inventors
- 👤 Paul Curt Muller
- 👤 Niklaus Kehl
- 👤 Egon Kreis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:07
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/78; H05B6/76
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
88 words
In a microwave tunnel-Oven having absorption sections enclosed by a metal casisng forming continuations of a central passage of said oven at both the inlet and outlet ends of said oven, the improvement comprising said absorption sections including a plurality of individual elongated load members of a ferrite material for absorbing microwaves, said plurality of ferrite load members being arranged between said casing and said continuations of said central passage at a distance next to one another in spaced relationship transversely to said continuations of said central passage.
Claim 2
Dependent Claim
88 words
In a microwave tunnel-Oven having absorption sections enclosed by a metal casisng forming continuations of a central passage of said oven at both the inlet and outlet ends of said oven, the improvement comprising said absorption sections including a plurality of individual elongated load members of a ferrite material for absorbing microwaves, said plurality of ferrite load members being arranged between said casing and said continuations of said central passage at a distance next to one another in spaced relationship transversely to said continuations of said central passage.
Claim 3
Dependent Claim
43 words
A tunnel-oven according to claim 1, including a lining surrounding said continuations of said central passage, which lining is composed of a dielectric material, and wherein said load members are arranged at a distance from said lining between said casing and said lining.
Claim 4
Dependent Claim
46 words
A tunnel-oven according to claim 2, wherein a layer of heat insulating material is arranged between said ferrite members and said metal casing, the spacing between said lining and said ferrite members being sufficient to allow a flow of cooling air to pass through said spacing.
Claim 5
Dependent Claim
33 words
A tunnel-oven according to claim 3, wherein the thickness of said layer of heat-insulating material is between two and three times the width of the spacing between said ferrite members and said lining.
Claim 6
Dependent Claim
21 words
A tunnel-oven according to claim 1, wherein said ferrite members are spaced apart by a distance approximately corresponding to their diameter.
Claim 7
Dependent Claim
39 words
A tunnel-oven according to claim 1, wherein additional load members are formed by individual portions of the turns of a tube which forms a spiral around said continuations of said central passage and is arranged to contain a liquid.
Claim 8
Dependent Claim
21 words
A tunnel-oven according to claim 6, wherein one end of said tube is connected to a source of pressurised cooling liquid.
Claim 9
Dependent Claim
48 words
A tunnel-oven according to claim 6, including a lining of a dielectric material surrounding said continuations of said central passage, and wherein said additional load members lie directly against said lining and said plurality of ferrite load members are arranged between said additional load members and said casing.
References Cited (Backward Citations)
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Cited
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US3564187A
Cited
US3624335A
Cited
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Cited
US3749874A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |