US3854327A
Expired / Lapsed
US
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Method and apparatus for determining the cross section of material using a sound field
Assignee: Zellweger Uster AG
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Filing: 1973-03-09
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Granted: 1974-12-17
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Expires: 1993-03-09
Abstract
Abstract Method and apparatus by which the approximate cross section of filamentary or wire form material is determined, wherein the material is passed through a sound field having standing waves of at least two different frequencies and sound pickups for detecting the frequencies so that the cross section of the material may be determined by changes in amplitude or phase of at least one of the waves. One standing wave serves to provide an indication of the cross section of the material while another standing wave adjusts the zero point of the measuring arrangement.
Inventors
- 👤 E Felix
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:38
CPC Classifications
G; G01; G01B; G01B17/00; B; B65; B65H; B65H63/00; B65H63/06; B65H63/062; B65H63/067; D; D01; D01H; D01H13/00; D01H13/14; D01H13/22; D01H5/00; D01H5/18; D01H5/32; D01H5/38; B65H2701/00; B65H2701/30; B65H2701/31
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
89 words
A method of at least approximately determining the cross section of filamentary or wire form material, comprising the steps of generating standing waves with at least two different frequencies within a resonator tuned such that at least one pressure maximum of the first standing wave and at least one pressure minimum of another standing wave substantially coincide at a point in the resonator, guiding the material to be tested through said point and detecting variations in said standing waves produced by the presence of said material to be tested.
Claim 2
Independent Claim
89 words
A method of at least approximately determining the cross section of filamentary or wire form material, comprising the steps of generating standing waves with at least two different frequencies within a resonator tuned such that at least one pressure maximum of the first standing wave and at least one pressure minimum of another standing wave substantially coincide at a point in the resonator, guiding the material to be tested through said point and detecting variations in said standing waves produced by the presence of said material to be tested.
Claim 3
Dependent Claim
16 words
A method as claimed in claim 1 wherein the standing waves are continuously and simultaneously generated.
Claim 4
Dependent Claim
19 words
A method as claimed in claim 1 wherein the standiNg waves of different frequencies are produced intermittently in succession.
Claim 5
Dependent Claim
48 words
A method as claimed in claim 1 wherein said step of detecting variations in the standing waves includes determining from the first standing wave the cross section of the test material and adjusting the zero point of the measuring arrangement on the basis of the other standing wave.
Claim 6
Dependent Claim
26 words
A method as claimed in claim 1, further including the step of feeding back the detected standing waves for spontaneously generating the waves in said resonator.
Claim 7
Dependent Claim
37 words
A method as claimed in claim 5 wherein said feeding back of the detected standing waves is performed so as to not produce any additional phase shift between the input to the resonator and the output thereof.
Claim 8
Dependent Claim
36 words
A method as claimed in claim 5 wherein said feeding back of the detected standing waves is performed so that an additional phase shift is produced between the input to the resonator and the output thereof.
Claim 9
Dependent Claim
33 words
A method as claimed in claim 5 wherein said feeding back of the detected standing waves is provided by separate parallel paths effecting feedback without phase shift and feedback with phase shift, respectively.
Claim 10
Dependent Claim
19 words
A method as claimed in claim 8 wherein the respective parallel feedback paths are alternately switched on and off.
Claim 11
Dependent Claim
18 words
A method as claimed in claim 1 wherein the ratio between the frequencies is at least approximately integral.
Claim 12
Dependent Claim
23 words
A method as claimed in claim 10 wherein the ratio of the frequencies is substantially that of an even to an odd integer.
Claim 13
Dependent Claim
28 words
A method as claimed in claim 1 wherein the standing waves of at least the higher frequencies are formed in a pair of resonators acting as open pipes.
Claim 14
Dependent Claim
58 words
A method as claimed in claim 1 wherein the frequencies are superimposed in two sound generators, one frequency being an approximately even-numbered multiple of a fundamental frequency while the other frequency is an odd-numbered multiple of this fundamental frequency, the said other frequency being delivered to one generator in phase and to the other generator in opposite phase.
Claim 15
Dependent Claim
51 words
A method as claimed in claim 1 wherein said step of detecting variations in the standing waves includes forming the sum and the difference from signals obtained by means of sound pickups from the standing waves, the sum and difference signals thus obtained each being returned to a respective sound generator.
Claim 16
Independent Claim
84 words
An apparatus for at least approximately determining the cross section of filamentary or wire form material comprising means for generating a sound field having standing waves of at least two different frequencies, sound pickup means disposed in spaced relationship to said sound generating means for detecting the said frequencies and means for guiding the said material through a zone in the aforementioned sound field at a point in which both a pressure maximum of one frequency and a velocity maximum of another frequency occur.
Claim 17
Independent Claim
84 words
An apparatus for at least approximately determining the cross section of filamentary or wire form material comprising means for generating a sound field having standing waves of at least two different frequencies, sound pickup means disposed in spaced relationship to said sound generating means for detecting the said frequencies and means for guiding the said material through a zone in the aforementioned sound field at a point in which both a pressure maximum of one frequency and a velocity maximum of another frequency occur.
Claim 18
Dependent Claim
31 words
An apparatus as claimed in claim 15 wherein the sound generator and the sound pickup are parts of an oscillating resonance system and are connected by at least one feedback path.
Claim 19
Dependent Claim
23 words
An apparatus as claimed in claim 16 wherein the sound field containing the standing waves determines the natural frequency of the resonance system.
Claim 20
Dependent Claim
18 words
An apparatus as claimed in claim 16 wherein there is at least one amplifier in the feedback path.
Claim 21
Dependent Claim
39 words
An apparatus as claimed in claim 18 wherein an amplifier which does not produce any phase shift is arranged in one feedback path, while an amplifier which does produce a phase shift is arranged in a second feedback path.
Claim 22
Dependent Claim
26 words
An apparatus as claimed in claim 15 wherein a sound generator for generating two frequencies and a sound pickup for detecting the said frequencies are provided.
Claim 23
Dependent Claim
35 words
An apparatus as claimed in claim 15 wherein a sound generator and a sound pickup are provided for generating one frequency and another sound generator and another sound pickup are provided for generating another frequency.
Claim 24
Dependent Claim
25 words
An apparatus as claiMed in claim 21 wherein the sound generators and the sound pickups are arranged one on either side of the sound field.
Claim 25
Dependent Claim
29 words
An apparatus as claimed in claim 22 wherein one sound generator and the corresponding sound pickup are arranged offset in relation to the other sound generator and sound pickup.
Claim 26
Dependent Claim
23 words
An apparatus as claimed in claim 15 wherein the sound generator and the sound pickup are in the form of an open pipe.
Claim 27
Dependent Claim
57 words
An apparatus as claimed in claim 15 wherein the frequencies are derived from a fundamental frequency, one of the derived frequencies being an odd-numbered multiple and the other frequency an approximately even-numbered multiple of this fundamental frequency, one of the frequencies being applied to one sound generator in phase and to another sound generator in opposite phase.
Claim 28
Dependent Claim
38 words
An apparatus as claimed in claim 15 comprising means for obtaining the sum and difference of the signals obtained from two sound pickups, the sums and differences thus formed being coupled back to at least one sound generator.
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) | 1977-12-16 | 1978-06-17 | 1978-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-16 | 1982-06-17 | 1982-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-16 | 1986-06-17 | 1986-12-17 | $7700.00 | Window Closed / Lapsed |