US3739263A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cross-sectional area measuring device
Assignee: INST MIKROVAGSTEKNIK
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Filing: 1971-09-27
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Granted: 1973-06-12
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Expires: 1991-09-27
Abstract
Abstract A device for measuring the cross-sectional area of an object such as a wire includes a resonant cavity through which the object passes. The resonant cavity is energized by a signal whose frequency periodically varies over a range which includes two distinct resonant modes of the cavity. By virtue of the passage of the object through the cavity both resonance frequencies change as a function of the cross-section of the object and the difference between these two resonance frequencies is a measure of the cross-section of the object.
Inventors
- 👤 B Henoch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:27
CPC Classifications
G; G01; G01B; G01B7/00; G01B7/12; G01B7/125
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
178 words
A device for the continuous measurement and/or monitoring of the cross-sectional area of an object having a longitudinal dimension which is very much larger than a transverse dimension comprising: a source of microwave electrical energy having a frequency periodically varying within a given frequency range; a microwave resonator cavity which is in the form of a symmetrical circular cylinder having closed ends and being provided with an opening in each of said ends at the axis of symmetry of the cylinder whereby the object can pass through said cavity, said cavity having such dimensions so as to have distinct resonance characteristics for energy of two separate modes of oscillation which have properties such that the resonant frequency of one mode of oscillation increases as the cross-sectional area of the object increases, and the resonant frequency of the other mode of oscillation decreases as the cross-sectional area increases, and means for measuring the difference between the two resonant frequencies, whereby the cross-sectional area of the object is obtained as a function of the difference between said two resonant frequencies.
Claim 2
Independent Claim
178 words
A device for the continuous measurement and/or monitoring of the cross-sectional area of an object having a longitudinal dimension which is very much larger than a transverse dimension comprising: a source of microwave electrical energy having a frequency periodically varying within a given frequency range; a microwave resonator cavity which is in the form of a symmetrical circular cylinder having closed ends and being provided with an opening in each of said ends at the axis of symmetry of the cylinder whereby the object can pass through said cavity, said cavity having such dimensions so as to have distinct resonance characteristics for energy of two separate modes of oscillation which have properties such that the resonant frequency of one mode of oscillation increases as the cross-sectional area of the object increases, and the resonant frequency of the other mode of oscillation decreases as the cross-sectional area increases, and means for measuring the difference between the two resonant frequencies, whereby the cross-sectional area of the object is obtained as a function of the difference between said two resonant frequencies.
Claim 3
Dependent Claim
103 words
A device in accordance with claim 1, characterized by the fact that the said cavity is constructed in such a way that one of the modes of oscillation sets up a high-frequency magnetic field at right angles to the longitudinal direction of the object, so that the resonant frequency of this mode of oscillation increases as the cross sectional area increases, and by the fact that the other mode of oscillation in that part of the cavity through which the object passes has mainly electrical energy, so that the resonant frequency of this mode of oscillation decreases as the cross sectional area increases.
Claim 4
Dependent Claim
125 words
A device in accordance with claim 1, characterized by the fact that the said cavity is constructed in such a way that one of the modes of oscillation sets up a high-frequency electrical field in the longitudinal direction of the object, so that the resonant frequency of this mode of oscillation increases as the cross sectional area increases, and by the fact that the other mode of oscillation in that part of the cavity through which the object passes has mainly electrical energy, so that the resonant frequency of this mode of oscillation decreases as the cross sectional area increases, and by the fact that passage of the object through the cavity is designed so that there is electRical contact between this and the cavity.
Claim 5
Dependent Claim
80 words
A device in accordance with claim 2 for the continuous measurement and/or monitoring of the thickness of the dielectric layer on a metallic object of large longitudinal dimension, characterized by the thickness of the layer being obtained as a function of the difference between two measurements of the said frequency difference, viz. one in a first cavity for the metallic object alone and the other in a second cavity for the metallic object with the dielectric layer applied to it.
Claim 6
Dependent Claim
39 words
A device in accordance with claim 2 wherein the ratio between the diameter D and height h of the cavity is equal to 2.15, and said frequency range is situated around 36.6/D GHz, where D is measured in cm.
Claim 7
Dependent Claim
62 words
A device in accordance with claim 3 wherein the ratio between the diameter D and height h of the cavity is approximately equal to 1.0, and said frequency range is situated around 23.1/D GHz, where D is measured in cm, and the passage of the object through the cavity is designed so that there is electrical contact between this and the cavity.
Claim 8
Dependent Claim
65 words
A device in accordance with claim 2 wherein the ratio between the diameter D and height h of the cavity is less than 2.3 and greater than 2.0, and the passage of the object through the cavity is designed to occur along the line of symmetry of the cavity in such a way that there is no electrical contact between the object and the cavity.
Claim 9
Dependent Claim
63 words
A device in accordance with claim 9, wherein the ratio between the Diameter D and height h of the cavity is less than 1.2 and greater than 0.8, and the passage of the object through the cavity is designed to occur along the line of symmetry of the cavity in such a way that there is electrical contact between this and the cavity.
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) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |