US4160144A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Single-sided microwave applicator for sealing cartons
Assignee: National Research Council Canada
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Filing: 1978-01-25
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Granted: 1979-07-03
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Expires: 1998-01-25
Abstract
Abstract The single-sided microwave applicator has a section of a microwave waveguide with an open end for receiving microwave energy and an end which is electrically shorted. A slot is located in one of the wide sides of the waveguide extending along the center line from the shorted end. A conductive ridge is mounted within the waveguide extending upward from the other side through the slot. One end of the ridge is connected to the shorted end of the waveguide, while the other end of the ridge is tapered from a point within the slot. The slot is generally in the order of 3/4 to 1 inch and at least 21/2 inches long, when the operating frequency is 2450 MHz. Since one end of the waveguide is shorted, standing waves are produced resulting in a non-uniform field having at least one maximum along the length of the slot. The electric field produced is non-radiating and its strength diminishes exponentially above the slot.
Inventors
- 👤 Satish C. Kashyap
- 👤 Walter Wyslouzil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:57
CPC Classifications
H; H01; H01Q; H01Q13/00; H01Q13/20; H01Q13/22; H05; H05B; H05B6/00; H05B6/64; H05B6/70; H05B6/701; H05B6/705; H05B6/707; B; B31; B31B; B31B50/00; B31B50/004; B31B50/60; B31B50/62; B31B50/626; B65; B65B; B65B51/00; B65B51/10; B65B51/22; B65B7/00; B65B7/16
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
162 words
A single-sided microwave applicator comprising: a section of rectangular microwave waveguide having two narrow sides and two wide sides, one end of the waveguide section being open to receive microwave energy for producing standing waves within the waveguide section and the other end of said waveguide section being shorted, the waveguide section further having an elongated slot in the first wide side, extending along the center line of the wide side from the shorted end of the waveguide section; and a conductive ridge mounted within the waveguide section along the center line of the second wide side, the ridge extending through the slot with one end in contact with the first wide side at the shorted end of the waveguide section and the other end of the ridge being tapered from within the slot to the second wide side of the waveguide, whereby a non-uniform electric field having at least one maximum is produced between the ridge and the first wide side.
Claim 2
Dependent Claim
162 words
A single-sided microwave applicator comprising: a section of rectangular microwave waveguide having two narrow sides and two wide sides, one end of the waveguide section being open to receive microwave energy for producing standing waves within the waveguide section and the other end of said waveguide section being shorted, the waveguide section further having an elongated slot in the first wide side, extending along the center line of the wide side from the shorted end of the waveguide section; and a conductive ridge mounted within the waveguide section along the center line of the second wide side, the ridge extending through the slot with one end in contact with the first wide side at the shorted end of the waveguide section and the other end of the ridge being tapered from within the slot to the second wide side of the waveguide, whereby a non-uniform electric field having at least one maximum is produced between the ridge and the first wide side.
Claim 3
Dependent Claim
31 words
A single-sided microwave applicator as claimed in claim 1 which further includes a layer of dielectric material located on the outer surface of the first wide side to cover the slot.
Claim 4
Dependent Claim
15 words
A single-sided microwave applicator as claimed in claim 2 wherein the dielectric material is teflon.
Claim 5
Dependent Claim
31 words
A single-sided microwave applicator as claimed in claim 1 wherein, for an operating frequency of 2450 MHz, the width of the slot is in the order of 0.75 to 1 inch.
Claim 6
Dependent Claim
20 words
A single-sided microwave applicator as claimed in claim 4 wherein the length of the slot is greater than 2.5 inches.
References Cited (Backward Citations)
US3402277A
Cited
US3456355A
Cited
US3555232A
Cited
US3783221A
Cited
US3679855A
Cited
US3886471A
Cited
US3999026A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-07-02 | 1983-01-01 | 1983-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-07-02 | 1987-01-01 | 1987-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-07-02 | 1991-01-01 | 1991-07-03 | $7700.00 | Window Closed / Lapsed |