US3761665A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microwave heating apparatus with looped wave guide and phase shifting means
Assignee: Toshiba Corp
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Filing: 1972-05-25
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Granted: 1973-09-25
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Expires: 1992-05-25
Abstract
Abstract A microwave heating apparatus comprises a directional coupler including a main wave guide receiving energy from a microwave oscillator and a supplementary wave guide coupled to the main wave guide and receiving microwave energy therefrom. A heating wave guide preferably provided with a movable short-circuiting plate at both ends is connected to the supplementary wave guide so as to transmit in the TM mode the microwaves generated by the microwave oscillator and conducted thereto through the directional coupler. A variable phase shifter is provided for bringing the microwaves fed back to the supplementary wave guide through the heating wave guide in-phase with the microwaves conducted to said supplementary wave guide from the microwave oscillator.
Inventors
- 👤 T Nagao
- 👤 T Okakura
- 👤 K Hasegawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:27
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/78
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
140 words
A microwave heating apparatus comprising: a microwave oscillator; a looped wave guide circuit for circulating microwaves received from the microwave oscillator in the same direction, said circuit including: a directional coupler comprised of a main wave guide connected at one end to the microwave oscillator and at the other end to a dummy load, and a supplementary wave guide coupled to and receiving energy from said main wave guide; and a heating wave guide coupled to said supplementary wave guide for transmitting in the TM mode the microwaves received from the microwave oscillator via said directional coupler; and means for bringing the microwaves circulating through the looped wave guide circuit in-phase with the microwaves supplied to said looped wave guide circuit from the microwave oscillator, thereby efficiently heating an object introduced in the axial direction of the heating wave guide.
Claim 2
Dependent Claim
140 words
A microwave heating apparatus comprising: a microwave oscillator; a looped wave guide circuit for circulating microwaves received from the microwave oscillator in the same direction, said circuit including: a directional coupler comprised of a main wave guide connected at one end to the microwave oscillator and at the other end to a dummy load, and a supplementary wave guide coupled to and receiving energy from said main wave guide; and a heating wave guide coupled to said supplementary wave guide for transmitting in the TM mode the microwaves received from the microwave oscillator via said directional coupler; and means for bringing the microwaves circulating through the looped wave guide circuit in-phase with the microwaves supplied to said looped wave guide circuit from the microwave oscillator, thereby efficiently heating an object introduced in the axial direction of the heating wave guide.
Claim 3
Dependent Claim
29 words
The microwave heating apparatus according to claim 1 wherein the heating wave guide is a circular type wave guide having a movable short-circuiting plate provided at both ends thereof.
Claim 4
Dependent Claim
31 words
The microwave heating apparatus according to claim 1 wherein said looped wave guide circuit includes first and second connection wave guides coupling said heating wave guide to said supplementary wave guide.
Claim 5
Dependent Claim
35 words
The microwave heating apparatus according to claim 3 wherein said connection wave guides are respectively connected at either end of said supplementary wave guide at right angles to the axis of said supplementary wave guide.
Claim 6
Dependent Claim
24 words
The microwave heating apparatus according to claim 4 wherein said connection wave guides are connected to said heating wave guide at right angles thereto.
Claim 7
Dependent Claim
30 words
The microwave heating apparatus according to claim 3 wherein said connection wave guides are connected to said supplementary wave guide and to said heating wave guide at right angles thereto.
Claim 8
Dependent Claim
27 words
The microwave heating apparatus according to claim 1 wherein said means for bringing the microwaves in-phase comprises a phase shifter located in said looped wave guide circuit.
Claim 9
Dependent Claim
28 words
The microwave heating apparatus according to claim 3 wherein said means for bringing the microwaves in-phase comprises a phase shifter located in one of said connection wave guides.
Claim 10
Dependent Claim
62 words
The microwave heating apparatus according claim 1 wherein said main wave guide and said supplementary wave guide are attached to each other and are oriented in the same direction, and wherein said directional coupler includes at least one hole in the walls of said main and supplementary wave guides for coupling energy from said main wave guide to said supplementary wave guide.
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) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |