US4073193A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transducer device
Assignee: Individual
•
Filing: 1976-10-04
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Granted: 1978-02-14
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Expires: 1996-10-04
Abstract
Abstract A transducer device and a system incorporating said transducer device useful, for example, for measuring a characteristic of particles in a particle flow stream. The transducer device comprises a front surface solid element in which an elastic wave is created, for example, on impact of a particle on an exposed front surface; a liquid medium; a thin piezoelectric sensing element; a solid back surface element; and a housing to hold the front and back surface elements in spaced relation with the liquid medium therebetween. Elastic waves created at the front surface are propagated through the piezoelectric element. The acoustic configuration of the transducer device is such that the electrical output signal of the thin piezoelectric is indicative of some characteristic of the first and the fastest pulse of the elastic wave. Systems including the transducer device comprise circuitry for processing the output of the piezoelectric transducer including, for example, amplifiers, filters, peak detectors, counters, rate meters, zero crossing detectors, etc. which provide an output characteristic, for example, of number, momentum, energy, mass, size and/or velocity of particles striking the front surface.
Inventors
- 👤 John R. Mastandrea
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:50
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/22; G01N29/24; G01N29/2437; G01N29/04; G01N29/045; G01N2291/00; G01N2291/02; G01N2291/024; G01N2291/02408; G01N2291/02416; G01N2291/028; G01N2291/02827; G01N2291/04; G01N2291/042; G01N2291/0421; G01N2291/0422; Y; Y10; Y10S; Y10S73/00; Y10S73/04
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
169 words
A transducer device comprising: a housing comprising a material of low elastic wave propagation velocity and high wave attenuation properties; a front surface element mounted at one end of said housing, said front surface element having a front surface arranged to accept mechanical energy for creating an elastic wave therein, said front surface element comprising a material having high elastic wave attenuation properties; a rear surface element mounted relative to said housing and spaced from said front surface element, said rear surface element comprising a material having high elastic wave attenuation properties; a thin transducer element mounted upon the rear surface element between the rear surface element and the front surface element; and means between the front surface element and the thin transducer for transmitting elastic waves but which means does not transmit transverse elastic waves, whereby a characteristic of the electrical signal output of said thin transducer element is related to the first and the fastest elastic wave created at the front surface of said front surface element.
Claim 2
Dependent Claim
169 words
A transducer device comprising: a housing comprising a material of low elastic wave propagation velocity and high wave attenuation properties; a front surface element mounted at one end of said housing, said front surface element having a front surface arranged to accept mechanical energy for creating an elastic wave therein, said front surface element comprising a material having high elastic wave attenuation properties; a rear surface element mounted relative to said housing and spaced from said front surface element, said rear surface element comprising a material having high elastic wave attenuation properties; a thin transducer element mounted upon the rear surface element between the rear surface element and the front surface element; and means between the front surface element and the thin transducer for transmitting elastic waves but which means does not transmit transverse elastic waves, whereby a characteristic of the electrical signal output of said thin transducer element is related to the first and the fastest elastic wave created at the front surface of said front surface element.
Claim 3
Dependent Claim
57 words
A system for monitoring particles in a particle flow stream comprising: a transducer device according to claim 1 arranged with the front surface in the path of said flow stream; means for processing the electric signal output of said thin transducer to produce an output signal indicative of a characteristic of the particles impinging the front surface.
Claim 4
Dependent Claim
46 words
A system according to claim 2 wherein said processing means detects the peak voltage of an output pulse of the thin transducer resulting from a particle impacting the front surface, said peak voltage being characteristic of the energy, mass, size and/or velocity of said impacting particle.
Claim 5
Dependent Claim
40 words
A system according to claim 2 wherein said processing means detects the initial pulse width of an output pulse of the thin transducer resulting from a particle impacting the front surface, said pulse width being indicative of velocity and/or momentum.
Claim 6
Dependent Claim
20 words
The system according to claim 2 wherein the processing means comprises a means for recording said thin transducer output signal.
Claim 7
Dependent Claim
35 words
The system according to claim 2 wherein the processing means filters the output of said thin transducer to pass only a signal corresponding to the first pulse resulting from a particle impacting the front surface.
Claim 8
Dependent Claim
22 words
The system according to claim 6 wherein the center frequency of the band passed by said processing means is approximately 500 kHz.
Claim 9
Dependent Claim
24 words
The system according to claim 6 wherein the processing means integrates the filtered signal over a selected time interval to provide a DC output.
Claim 10
Dependent Claim
34 words
The system according to claim 6 wherein the means for processing comprises means for counting the pulses in the filtered signal, said count being indicative of the number of particles striking the front surface.
Claim 11
Dependent Claim
38 words
The system according to claim 6 wherein the means for processing comprises means for measuring the rate of pulses in the filtered signal, said rate being indicative of the rate of impact of particles on the front surface.
Claim 12
Dependent Claim
189 words
A transducer device comprising: a housing comprising a material of low elastic wave propagation velocity and high elastic wave attenuation properties; a front surface element mounted at one end of said housing, said front surface element having a front surface arranged to accept mechanical energy for creating an elastic wave, said front surface element comprising a material having high elastic wave attenuation properties; a rear surface element mounted relative to said housing and spaced from said front surface element, said rear surface element comprising a material having high elastic wave attenuation properties; a thin piezoelectric transducer element mounted upon the rear surface element between the rear surface element and the front surface element; a damping material surrounding the rear surface element filling the space between the rear surface material and the housing; and liquid means between the front surface element and the thin transducer element for transmitting elastic waves but which does not transmit transverse elastic waves, whereby a characteristic of the electric signal output of said thin transducer is related to the first and the fastest elastic wave created at the front surface of said front surface element.
Claim 13
Dependent Claim
189 words
A transducer device comprising: a housing comprising a material of low elastic wave propagation velocity and high elastic wave attenuation properties; a front surface element mounted at one end of said housing, said front surface element having a front surface arranged to accept mechanical energy for creating an elastic wave, said front surface element comprising a material having high elastic wave attenuation properties; a rear surface element mounted relative to said housing and spaced from said front surface element, said rear surface element comprising a material having high elastic wave attenuation properties; a thin piezoelectric transducer element mounted upon the rear surface element between the rear surface element and the front surface element; a damping material surrounding the rear surface element filling the space between the rear surface material and the housing; and liquid means between the front surface element and the thin transducer element for transmitting elastic waves but which does not transmit transverse elastic waves, whereby a characteristic of the electric signal output of said thin transducer is related to the first and the fastest elastic wave created at the front surface of said front surface element.
Claim 14
Dependent Claim
25 words
A transducer device according to claim 11 wherein a thin coating of a wear resistant material covers the front surface of the front surface element.
Claim 15
Dependent Claim
29 words
A transducer device according to claim 11 wherein the thin piezoelectric transducer is selected from a group comprising flourinated ethylene, polyvinylflouride and tetrafluoroethylene electrets with electrodes on each face.
Claim 16
Dependent Claim
24 words
A transducer device according to claim 11 wherein the liquid means comprises a material selected from the group consisting of water, grease and oil.
Claim 17
Dependent Claim
14 words
A transducer device according to claim 11 wherein the front surface material is lead.
Claim 18
Dependent Claim
23 words
A transducer device according to claim 11 wherein the back surface material is selected from the group comprising zinc, lead, plastic and rubber.
References Cited (Backward Citations)
US3159029A
Cited
US3179823A
Cited
US3365593A
Cited
GB1254493A
Cited
US3844174A
Cited
US3830103A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-13 | 1981-08-15 | 1982-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-13 | 1985-08-15 | 1986-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-13 | 1989-08-15 | 1990-02-14 | $7700.00 | Window Closed / Lapsed |