US3673370A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave applicator system with cylindrical resonant cavity
Assignee: MICRODRY Inc A CORP OF KENTUCKY
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Filing: 1970-04-03
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Granted: 1972-06-27
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Expires: 1990-04-03
Abstract
Abstract A cylindrical microwave resonant cavity is excited in the TM010 mode to generate an electric field extending parallel to the axis of the cavity and having a maximum intensity along the axis. A filament or thread is conveyed axially through the cavity and heated. The cavity housing is formed into two sections along radial planes. The sections are hinged about a line parallel to the axis to facilitate opening the housing and cleaning its interior. Liners may be provided to cover the interior of each section. A slot is formed between the sections opposite the hinge line for threading the filament into its operative axial position. Clamps are provided to resiliently urge the sections together, yet the clamps permit adjustment of the angle of inclination between the sections by means of a screw mechanism to tune the resonant frequency of the cavity to the operating frequency of the microwave source. Air, preheated by cooling the source, is routed through the feed guide into the cavity to purge vapors from the cavity and prevent accumulation of residue. An electrical interlock is provided to inhibit operation of the microwave source when the sections are separated beyond a predetermined limit.
Inventors
- 👤 Ray M Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:23
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/78; H05B6/782; H01; H01P; H01P7/00; H01P7/06
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
143 words
In a system for applying microwave energy to material, the combination comprising resonant cavity means including a cylindrical side wall and formed by first and second separatable housing sections, hinge means pivotally securing said first and second sections about a hinge line extending generally parallel to the axis of said side wall whereby said sections may be moved to a closed position in which the sides of said sections form the general shape of a cylinder or split apart to gain access to the interior of said cavity, microwave energy source means for exciting said cavity to generate an electric field within said cavity extending generally parallel to the axis of said side wall when closed and having a maximum intensity in the neighborhood of said axis, said housing sections defining aperture means for transporting said material through the axis of said cavity.
Claim 2
Dependent Claim
143 words
In a system for applying microwave energy to material, the combination comprising resonant cavity means including a cylindrical side wall and formed by first and second separatable housing sections, hinge means pivotally securing said first and second sections about a hinge line extending generally parallel to the axis of said side wall whereby said sections may be moved to a closed position in which the sides of said sections form the general shape of a cylinder or split apart to gain access to the interior of said cavity, microwave energy source means for exciting said cavity to generate an electric field within said cavity extending generally parallel to the axis of said side wall when closed and having a maximum intensity in the neighborhood of said axis, said housing sections defining aperture means for transporting said material through the axis of said cavity.
Claim 3
Dependent Claim
25 words
The system of claim 1 further comprising means for continuously forcing air into the interior of said cavity to purge the same of moisture vapor.
Claim 4
Dependent Claim
52 words
The system of claim 2 wherein said last-named means includes means receiving heated air passed over the source of microwave energy and forcing the same through said excitation means and into said cavity to be exhausted through said aperture means at a rate in the range of 80-120 cubic feet per minute.
Claim 5
Dependent Claim
60 words
The system of claim 1 wherein said housing sections are semi-cylindrical in form and are separated along a plane passing through said axis and wherein said cavity further includes transverse end plates at each end of each of said sections, said end plates defining inlet and outlet apertures for permitting passage of a resonent along the axis of said cavity.
Claim 6
Dependent Claim
59 words
The system of claim 1 further comprising means for resiliently urging said housing sections in a closed position, and further comprising adjusting mechanism including screw thread means secured to one of said housing sections and engaging the other for selectively moving said sections relative to each other about said hinge means to tune said resonant frequency of said cavity.
Claim 7
Dependent Claim
91 words
The system of claim 1 further comprising first and second neck members secured respectively to said first and second housing sections adjacent said aperture means throuGh which said material passes, spring means engaging said neck members for urging the same together to bias said housing sections in closed position, and adjustable means secured to one of said housing sections and engaging the other section to force said sections apart against the action of said spring means to adjust the angle between said sections in tuning the resonant frequency of said cavity.
Claim 8
Dependent Claim
38 words
The system of claim 1 further comprising electrical interlock means responsive to the separation between said housing sections for preventing the excitation of said cavity by said microwave source when said sections are open beyond a predetermined limit.
Claim 9
Dependent Claim
47 words
The system of claim 7 further comprising probe means mounted on said cavity housing and including a probe extending into the cavity adjacent the cylindrical side wall for monitoring the energy therein in tuning the resonant frequency of said cavity to the frequency of the microwave source.
Claim 10
Dependent Claim
37 words
The system of claim 1 wherein said excitation means includes a rectangular waveguide defining an iris in register with a corresponding aperture in the side wall of said cavity for exciting the same in the TM010 mode.
Claim 11
Dependent Claim
43 words
The system of claim 1 wherein said housing sections are separated along one plane extending through said axis and wherein said material is a filament and said aperture means includes an inlet and an outlet aperture for passing said filament along said axis.
Claim 12
Dependent Claim
27 words
The system of claim 10 wherein the separation between said cavity sections from the axis to the side opposite said hinge means permits threading of said filament.
Claim 13
Dependent Claim
117 words
In a system for applying microwave energy to a filament, the combination comprising resonate cylindrical cavity means excited by microwave source means to generate an electric field having maximum intensity along the axis of said cavity and provided with transverse end plates each defining an axial aperture for permitting passage of said thread through the axis of said cavity and along the region of maximum field intensity of said cavity when excited, said cavity being divided into first and second separatable housing sections, and tuning means for predetermining the separation between said halves about a hinge line to tune the resonant frequency of said cavity to the frequency of a source of microwave energy exciting the same.
Claim 14
Dependent Claim
117 words
In a system for applying microwave energy to a filament, the combination comprising resonate cylindrical cavity means excited by microwave source means to generate an electric field having maximum intensity along the axis of said cavity and provided with transverse end plates each defining an axial aperture for permitting passage of said thread through the axis of said cavity and along the region of maximum field intensity of said cavity when excited, said cavity being divided into first and second separatable housing sections, and tuning means for predetermining the separation between said halves about a hinge line to tune the resonant frequency of said cavity to the frequency of a source of microwave energy exciting the same.
Claim 15
Dependent Claim
32 words
The system of claim 12 wherein said tuning means further comprising resilient means urging said housing sections together and rigid means for setting the minimum distance at which said sections may close.
Claim 16
Dependent Claim
103 words
In a system for applying microwave energy the combination comprising resonant cavity means including a cylindrical side wall and provided with aperture means to pass the material being treated through the axis thereof, microwave source means including feed means connected to said cavity for exciting said cavity to generate an electric field having a maximum intensity along said axis, and means for passing air through said feed means and into said cavity to purge vapors from said cavity at least partially through said aperture means and to minimize the collection of material about the connection between said feed means and said cavity means.
Claim 17
Dependent Claim
103 words
In a system for applying microwave energy the combination comprising resonant cavity means including a cylindrical side wall and provided with aperture means to pass the material being treated through the axis thereof, microwave source means including feed means connected to said cavity for exciting said cavity to generate an electric field having a maximum intensity along said axis, and means for passing air through said feed means and into said cavity to purge vapors from said cavity at least partially through said aperture means and to minimize the collection of material about the connection between said feed means and said cavity means.
Claim 18
Dependent Claim
35 words
The system of claim 14 wherein said feed means includes hollow waveguide means exciting said cavity through a coupling aperture and wherein said air is preheated and passed through said waveguide and said coupling aperture.
Claim 19
Dependent Claim
36 words
The system of claim 14 wherein said cavity is characterized by having first and second semi-cylindrical sections separatable about a hinge line along the side wall thereof to facilitate access to the interior of said cavity.
Claim 20
Dependent Claim
55 words
The system of claim 14 wherein said source means includes a magnetron oscillator, and further comprising stabilizing network means connected in circuit with said cavity and said source means for causing said magnetron to oscillate at the resonant frequency of said cavity and thereby establish the coupling of power to said cavity from saiD source.
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) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |