US3843860A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Twisted microwave applicator
Assignee: Varian Medical Systems Inc
•
Filing: 1973-09-21
•
Granted: 1974-10-22
•
Expires: 1993-09-21
Abstract
Abstract A twisted microwave applicator is provided to avoid the heating non-uniformities inherently resulting from non-twisted microwave applicators. The invention comprises a section of waveguide twisted about its axis, preferably twisted 90* or more. The applicator is coupled to a microwave generator by conventional techniques. The objects to be treated are introduced into one end of the applicator, transported through the applicator and removed at the other end. The twisted waveguide provides for rotation of the field pattern, which tends to subject all portions of the objects to the same overall heating effect.
Inventors
- 👤 H Jory
- 👤 C Will
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:57
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/70; H01; H01P; H01P1/00; H01P1/02; H01P1/022; H05B6/6402; H05B6/80
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
133 words
An electromagnetic energy applicator comPrising a waveguide section elongate about an axis and having electromagnetic energy input means connected thereto, said waveguide section having two rectangular end walls with openings therein for passage of an object along a path through said waveguide section, said end walls being substantially opague to said electromagnetic energy, said waveguide section being configured so that the longer rectangular dimension of one of said end walls is nonparallel to the longer rectangular dimension of the other of said end walls, said waveguide section being further configured so that as said object passes along said path from said one end wall to said other end wall said object is exposed for the greater portion of said path to a continuously varying orientation of the electric field of said electromagnetic energy.
Claim 2
Dependent Claim
133 words
An electromagnetic energy applicator comPrising a waveguide section elongate about an axis and having electromagnetic energy input means connected thereto, said waveguide section having two rectangular end walls with openings therein for passage of an object along a path through said waveguide section, said end walls being substantially opague to said electromagnetic energy, said waveguide section being configured so that the longer rectangular dimension of one of said end walls is nonparallel to the longer rectangular dimension of the other of said end walls, said waveguide section being further configured so that as said object passes along said path from said one end wall to said other end wall said object is exposed for the greater portion of said path to a continuously varying orientation of the electric field of said electromagnetic energy.
Claim 3
Dependent Claim
123 words
The applicator of claim 1 wherein said waveguide section forms a resonant cavity; and wherein said waveguide section comprises a twisted portion interposed between two nontwisted portions; said end walls being disposed to permit passage of said object sequentially through one of said non-twisted portions, then through said twisted portion, and then through the other of said non-twisted portions along said path; each of said non-twisted portions having a length along said path sufficient to provide a non-zero electric field intensity at the boundary between said non-twisted portion and said twisted portion; said twisted portion having a length along said path sufficient to provide that said object is exposed to more of said energy in said twisted portion than in said non-twisted portions.
Claim 4
Dependent Claim
19 words
The applicator of claim 2 wherein said twisted portion of said waveguide section is twisted by at least 90*.
Claim 5
Dependent Claim
32 words
The applicator of claim 2 wherein the length of each of said non-twisted portions of said waveguide section is on the order of one-quarter of the waveguide wavelength of said electromagnetic energy.
Claim 6
Dependent Claim
86 words
The applicator of claim 1 wherein said waveguide section comprises a twisted portion interposed between two non-twisted portions; said end walls being disposed to permit passage of said object sequentially through one of said non-twisted portions, then through said twisted portion, and then through the other of said non-twisted portions along said path; the length of each of said non-twisted portions along said path being sufficient to provide maximum electric field intensity of said energy at the boundary between said non-twisted portion and said twisted portion.
Claim 7
Dependent Claim
30 words
The applicator of claim 5 wherein the length of each of said non-twisted portion along said path is substantially no longer than one-quarter of the waveguide wavelength of said energy.
Claim 8
Dependent Claim
147 words
The applicator of claim 1 wherein said applicator further comprises electromagnetic energy output means connected to said waveguide section; said waveguide section comprising a twisted portion interposed between two non-twisted portions; said end walls being disposed to permit passage of said object sequentially through one of said nontwisted portions, then through said twisted portion, and then through the other of said non-twisted portions along said path; one of said non-twisted portions having a length sufficient to accommodate thereon the connection of said electromagnetic energy input means to said waveguide section and the other of said non-twisted portions having a length sufficient to accommodate thereon the connection of said electromagnetic energy output means to said waveguide section; said twisted portion having a length along said path sufficient to provide that said object is exposed to more of said energy in said twisted portion than in said nontwisted portions.
Claim 9
Dependent Claim
19 words
The applicator of claim 7 wherein said twisted portion of said waveguide section is twisted by at least 90*.
Claim 10
Dependent Claim
88 words
The applicator of claim 1 wherein said waveguide section comprises a twisted portion interposed between two non-twisted portions; said end walls being disposed to permit passage of said object sequeNtially through one of said non-twisted portions, then through said twisted portion, and then through the other of said non-twisted portions along said path; the length of each of said non-twisted portions along said path being sufficiently small to provide that said object is exposed to more of said energy in said twisted portion than in said non-twisted portions.
Claim 11
Dependent Claim
13 words
The applicator of claim 1 wherein said waveguide section forms a resonant cavity.
Claim 12
Dependent Claim
19 words
The applicator of claim 1 wherein said rectangular end walls are perpendicular to said axis of said waveguide section.
Claim 13
Dependent Claim
29 words
The applicator of claim 1 wherein said electromagnetic energy input means comprises an energy input waveguide which is electromagnetically coupled to said object-treating waveguide section through an iris opening.
Claim 14
Dependent Claim
37 words
The applicator of claim 1 wherein said electromagnetic energy input means comprises an energy input waveguide which is elongate about an axis, said energy input waveguide axis being perpendicular to the axis of said object-treating waveguide section.
Claim 15
Dependent Claim
33 words
The applicator of claim 13 wherein the interface between said energy input waveguide and said object-treating waveguide section lies in a plane which is perpendicular to said axis of said energy input waveguide.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-21 | 1978-04-22 | 1978-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-21 | 1982-04-22 | 1982-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-21 | 1986-04-22 | 1986-10-22 | $7700.00 | Window Closed / Lapsed |