US4861955A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Matched absorptive end choke for microwave applicators
Assignee: Cyclean Inc
•
Filing: 1987-07-09
•
Granted: 1989-08-29
•
Expires: 2007-07-09
Abstract
Abstract A microwave application chamber including a reactive and absorptive choke is shown and described. The absorptive choke is made of a material having the same or close dielectric constant as the material being treated so that microwave energy will pass readily from the material being treated into the absorptive choke. The interface between the absorptive choke and the material being treated is essentially transparent to microwave without reflections. This transparency permits microwave energy to be absorbed in the absorptive choke which otherwise would follow the waveguide created by the material being treated and exit into the environment.
Inventors
- 👤 Zhi-Yuan Shen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:29
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/78; H05B6/76
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
75 words
A tunnel microwave applicator comprising in combination: material in said tunnel which is treated with microwaves; a microwave generator in said tunnel; a conveyor belt extending through an opening in said applicator; a concrete absorptive choke surrounding said conveyor at said opening in said applicator; and said absorptive choke having a dielectric constant which prevents the wave guide effect in said material on said conveyor and allows microwave energy to pass into said choke material.
Claim 2
Dependent Claim
75 words
A tunnel microwave applicator comprising in combination: material in said tunnel which is treated with microwaves; a microwave generator in said tunnel; a conveyor belt extending through an opening in said applicator; a concrete absorptive choke surrounding said conveyor at said opening in said applicator; and said absorptive choke having a dielectric constant which prevents the wave guide effect in said material on said conveyor and allows microwave energy to pass into said choke material.
Claim 3
Dependent Claim
21 words
The tunnel microwave applicator of claim 1, further comprising an absorptive choke which includes passages through which a coolant is passed.
Claim 4
Dependent Claim
12 words
The tunnel microwave applicator of claim 2, wherein the coolant is water.
Claim 5
Dependent Claim
26 words
A microwave applicator of claim 1 wherein said dielectric constant of said choke material is the same as the dielectric constant as said material being treated.
Claim 6
Dependent Claim
43 words
A microwave applicator of claim 1 wherein said dielectric constant of said choke material is close enough to the dielectric constant of said material being treated that all microwaves in said material being treated pass into said choke material and are absorbed therein.
Claim 7
Dependent Claim
40 words
A microwave applicator of claim 1 wherein said dielectric constant of said choke material is close enough to the dielectric constant of said material being treated that the electrical interface between said material being treated and said choke material disappears.
Claim 8
Dependent Claim
37 words
A microwave applicator of claim 1 wherein said dielectric constant of said choke material is close enough to the dielectric constant of said material being treated that there is no reflection of microwaves from said choke material.
Claim 9
Dependent Claim
15 words
The microwave applicator of claim 1 wherein said choke material closely surrounds said conveyor belt.
Claim 10
Dependent Claim
46 words
A microwave applicator of claim 1 wherein said dielectric constant of said choke material is close enough to the dielectric constant of said material being treated that there is no reflection of the microwaves at the interface of said material being treated and said choke material.
Claim 11
Dependent Claim
41 words
A microwave application of claim 1 wherein said absorptive choke attenuation is estimated by the following formula: a=10 log 180 dB where is the span angle of the opening as seen from the end of the choke where the product passes.
Claim 12
Dependent Claim
121 words
A tunnel microwave applicator comprising in combination: a microwave generator in said tunnel; material in said tunnel which is treated with microwaves; a conveyor belt extending through an opening of said applicator; a reactive choke at said conveyor opening of said applicator for reflecting microwave radiation back to the applicator and into material on said conveyor, said reactive choke having a first end connected to said microwave applicator and having a second end; and an absorptive choke connected to said second end of said reactive choke, wherein said absorptive choke is constructed of a material having a dielectric constant which prevents the wave guide effect in said material on said conveyor and allows microwave energy to pass into said choke material.
Claim 13
Dependent Claim
121 words
A tunnel microwave applicator comprising in combination: a microwave generator in said tunnel; material in said tunnel which is treated with microwaves; a conveyor belt extending through an opening of said applicator; a reactive choke at said conveyor opening of said applicator for reflecting microwave radiation back to the applicator and into material on said conveyor, said reactive choke having a first end connected to said microwave applicator and having a second end; and an absorptive choke connected to said second end of said reactive choke, wherein said absorptive choke is constructed of a material having a dielectric constant which prevents the wave guide effect in said material on said conveyor and allows microwave energy to pass into said choke material.
Claim 14
Dependent Claim
23 words
A tunnel microwave applicator in accordance with claim 11, wherein said material on said conveyor is the same material as said absorptive choke.
Claim 15
Dependent Claim
25 words
A tunnel microwave applicator in accordance with claim 1, wherein coolant is passed through tubes in said absorptive choke for dissipating and removing excess heat.
Claim 16
Dependent Claim
14 words
A tunnel microwave applicator in accordance with claim 13, wherein the coolant is water.
Claim 17
Dependent Claim
23 words
A tunnel microwave applicator in accordance with claim 13, wherein said cooling tubes are constructed of any material which is transparent to microwaves.
Claim 18
Dependent Claim
38 words
A tunnel microwave applicator in accordance with claim 12, wherein said absorptive choke is constructed of concrete containing aggregate having a dielectric material which has the same or close dielectric constant as the material carried on said conveyor.
Claim 19
Dependent Claim
24 words
A tunnel microwave applicator in accordance with claim 16, wherein said absorptive choke is constructed by pouring concrete around hoses placed in said concrete.
Claim 20
Dependent Claim
18 words
A tunnel microwave applicator in accordance with claim 16, wherein said absorptive material is a ferrite loaded rubber.
Claim 21
Dependent Claim
16 words
A tunnel microwave applicator in accordance with claim 11, wherein said absorptive choke is water cooled.
Claim 22
Dependent Claim
19 words
A tunnel microwave applicator in accordance with claim 11, wherein said absorptive choke is enclosed in a metallic enclosure.
Claim 23
Dependent Claim
19 words
A tunnel microwave applicator in accordance with claim 11, wherein said reactive choke is enclosed in a metallic enclosure.
Claim 24
Dependent Claim
31 words
A tunnel microwave applicator in accordance with claim 11, wherein said conveyor belt carries high dielectric constant materials such as having a depth of more than half wavelength in the material.
Claim 25
Dependent Claim
24 words
A tunnel microwave applicator in accordance with claim 11, wherein said absorptive choke is above, on both sides of, and below a non-metallic conveyor.
Claim 26
Dependent Claim
23 words
A tunnel microwave applicator in accordance with claim 11, wherein said absorptive choke is above, and on both sides of a metallic conveyor.
Claim 27
Dependent Claim
17 words
A tunnel microwave applicator in accordance with claim 7, wherein said reactive choke is a corrugated choke.
Claim 28
Dependent Claim
18 words
A tunnel microwave applicator in accordance with claim 11, wherein said reactive choke is a doubly corrugated choke.
Claim 29
Dependent Claim
15 words
The microwave applicator of claim 11 wherein said choke material closely surrounds said conveyor belt.
References Cited (Backward Citations)
US3365562A
Cited
US3624335A
Cited
US3858022A
Cited
US3909574A
Cited
US4319856A
Cited
US4488027A
Cited
US4570045A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-28 | 1993-02-27 | 1993-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-28 | 1997-02-27 | 1997-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-28 | 2001-02-27 | 2001-08-29 | $7700.00 | Window Closed / Lapsed |