US3939405A
Expired / Lapsed
US
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Apparatus and method for making decay rate measurements
Assignee: Deere and Co
•
Filing: 1974-08-19
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Granted: 1976-02-17
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Expires: 1994-08-19
Abstract
Abstract An apparatus and method is described for automatically measuring the rate of decay of oscillation in mechanical structures, acoustical enclosures, and electrical circuits which have been suitably excited. The apparatus includes a source of excitation energy being applied by a transducer to one point to produce oscillation in the form of vibrations, sound, or electrical pulsations. To initiate measurement, the excitation is terminated, a dual trace oscilloscope is triggered, a data processing circuit is operationalized, and a reference decay rate signal is generated. A pickup transducer at a second point converts the decaying oscillation into an input signal which the data processing circuit absolute-values and log-converts to provide a decaying data signal for display as a slope on the oscilloscope. The reference decay rate signal is generated from an adjustable reference signal by integration and is displayed as a slope on the oscilloscope. By adjusting the reference signal, the reference decay rate signal slope is adjusted to match the slope of the decaying data signal and then the rate of decay which is the value of the slope is determined directly from the value of the reference signal.
Inventors
- 👤 John Stefan Mutziger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:14
CPC Classifications
G; G01; G01H; G01H7/00; G01R; G01R31/00; G01R31/28; G01R31/2832; G01R31/2836; G01R31/2837
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
111 words
Apparatus for indicating the exponential rate of decay of oscillation in test objects such as mechanical structures, acoustical enclosures, or electrical circuits which have been excited and providing simultaneous indication of an adjustable reference decay rate signal for comparison comprising: means for exciting the test object and terminating the excitation; means for detecting the excitation response and providing a signal proportional thereto; means for receiving and processing the excitation response signal to produce an absolute-valued, log-converted decaying data signal; means for producing a variable, integrated reference decay rate signal simultaneously with the decaying data signal; indicator means for simultaneously presenting the reference decay rate signal and decaying data signal for comparison.
Claim 2
Dependent Claim
111 words
Apparatus for indicating the exponential rate of decay of oscillation in test objects such as mechanical structures, acoustical enclosures, or electrical circuits which have been excited and providing simultaneous indication of an adjustable reference decay rate signal for comparison comprising: means for exciting the test object and terminating the excitation; means for detecting the excitation response and providing a signal proportional thereto; means for receiving and processing the excitation response signal to produce an absolute-valued, log-converted decaying data signal; means for producing a variable, integrated reference decay rate signal simultaneously with the decaying data signal; indicator means for simultaneously presenting the reference decay rate signal and decaying data signal for comparison.
Claim 3
Dependent Claim
35 words
Apparatus as claimed in claim 1 including means for simultaneously terminating the excitation, producing the reference decay rate signal, and presenting the reference decay rate signal and the decaying data signal on the indicator means.
Claim 4
Dependent Claim
35 words
Apparatus as claimed in claim 1 including range multiplier means proportionately changing the reference signal within a predetermined range so as to provide a wider range of adjustment for the variable reference decay rate signal.
Claim 5
Dependent Claim
35 words
Apparatus as claimed in claim 1 wherein the indicator means is dual trace visual recorder with one trace responsive to the decaying data signal and the other trace to the variable reference decay rate signal.
Claim 6
Dependent Claim
234 words
Apparatus for indicating the rate of decay of oscillation in test objects such as mechanical structures, acoustical enclosures, and electrical circuits which have been suitably excited and providing simultaneous presentation of an adjustable reference decay rate signal for comparison comprising: a source of excitation energy for exciting a test object with the excitation energy in such forms as acoustical, mechanical, or electrical energy at a first predetermined point; means for terminating the excitation energy; means for detecting the excitation response of the test object at a second predetermined point and providing an input signal representative of the excitation response of the test object; means for receiving the input signal and producing a signal which is the absolute value of the input signal; means for log-converting the absolute-value signal and producing a decaying data signal which is the logarithmic value of the absolute-value signal; means for generating and varying a reference signal within a predetermined amplitude range and providing an indication of the value of the amplitude; means for integrating the reference signal and producing a reference decay rate signal made variable by varying the reference signal; means responsive to the means for terminating the excitation energy for triggering indicator means responsive to the decaying data signal and the reference decay rate signal for producing an indication representative of the decaying data signal from the test object and the variable decay rate for simultaneous comparison.
Claim 7
Dependent Claim
234 words
Apparatus for indicating the rate of decay of oscillation in test objects such as mechanical structures, acoustical enclosures, and electrical circuits which have been suitably excited and providing simultaneous presentation of an adjustable reference decay rate signal for comparison comprising: a source of excitation energy for exciting a test object with the excitation energy in such forms as acoustical, mechanical, or electrical energy at a first predetermined point; means for terminating the excitation energy; means for detecting the excitation response of the test object at a second predetermined point and providing an input signal representative of the excitation response of the test object; means for receiving the input signal and producing a signal which is the absolute value of the input signal; means for log-converting the absolute-value signal and producing a decaying data signal which is the logarithmic value of the absolute-value signal; means for generating and varying a reference signal within a predetermined amplitude range and providing an indication of the value of the amplitude; means for integrating the reference signal and producing a reference decay rate signal made variable by varying the reference signal; means responsive to the means for terminating the excitation energy for triggering indicator means responsive to the decaying data signal and the reference decay rate signal for producing an indication representative of the decaying data signal from the test object and the variable decay rate for simultaneous comparison.
Claim 8
Independent Claim
159 words
A method of determining the exponential decay rate of a test object which comprises the steps of: exciting the test object at a first selected point; terminating the excitation imposed on the test object; converting the decay response of the test object due to the termination of the excitation into an electrical input signal at a second selected point; absolute valuing of the electrical input signal to obtain an absolute-value electrical signal; log converting the absolute value electrical signal to obtain a decaying data electrical signal which is a logarithmic value of the absolute-value signal; generating an adjustable reference signal upon the termination of the excitation; integrating the adjustable reference signal to produce a variable reference decay rate electrical signal; adjusting the reference signal to produce a reference decay rate electrical signal which coincides with the decaying data electrical signal whereby the decay rate of the test object may be determined from the value of the adjusted reference signal.
Claim 9
Independent Claim
159 words
A method of determining the exponential decay rate of a test object which comprises the steps of: exciting the test object at a first selected point; terminating the excitation imposed on the test object; converting the decay response of the test object due to the termination of the excitation into an electrical input signal at a second selected point; absolute valuing of the electrical input signal to obtain an absolute-value electrical signal; log converting the absolute value electrical signal to obtain a decaying data electrical signal which is a logarithmic value of the absolute-value signal; generating an adjustable reference signal upon the termination of the excitation; integrating the adjustable reference signal to produce a variable reference decay rate electrical signal; adjusting the reference signal to produce a reference decay rate electrical signal which coincides with the decaying data electrical signal whereby the decay rate of the test object may be determined from the value of the adjusted reference signal.
Claim 10
Dependent Claim
24 words
The method as claimed in claim 6 wherein the terminating of the excitation is done simultaneously with the integrating of the adjustable reference signal.
Claim 11
Independent Claim
162 words
The method of determining the exponential electrical decay rate in a circuit which comprises the steps of: exciting the electrical circuit with an oscillating electrical signal at a first selected point; terminating the electrical signal imposed on the circuit; detecting the electrical decay response signal of the circuit due to the termination of the electrical signal at a second selected point; absolute valuing the electrical decay response signal to obtain an absolute-value electrical signal; log converting the absolute-value electrical signal to obtain a decaying data signal which is a logarithmic value of the absolute-value electrical signal; generating an adjustable reference signal upon the termination of the electrical signal; processing the adjustable reference signal to produce a variable reference decay rate electrical signal; adjusting the adjustable reference signal until the variable reference decay rate electrical signal coincides with the decaying data electrical signal whereby the electrical decay rate characteristics of the circuit may be determined from the value of the adjusted reference signal.
Claim 12
Independent Claim
162 words
The method of determining the exponential electrical decay rate in a circuit which comprises the steps of: exciting the electrical circuit with an oscillating electrical signal at a first selected point; terminating the electrical signal imposed on the circuit; detecting the electrical decay response signal of the circuit due to the termination of the electrical signal at a second selected point; absolute valuing the electrical decay response signal to obtain an absolute-value electrical signal; log converting the absolute-value electrical signal to obtain a decaying data signal which is a logarithmic value of the absolute-value electrical signal; generating an adjustable reference signal upon the termination of the electrical signal; processing the adjustable reference signal to produce a variable reference decay rate electrical signal; adjusting the adjustable reference signal until the variable reference decay rate electrical signal coincides with the decaying data electrical signal whereby the electrical decay rate characteristics of the circuit may be determined from the value of the adjusted reference signal.
Claim 13
Independent Claim
157 words
The method of determining sound decay rate of an enclosure which comprises the steps of: exciting the enclosure with sound at a first selected point; terminating the excitation sound imposed on the enclosure; converting the sound decay of the enclosure due to the termination of the excitation sound into an electrical input signal at a second selected point; absolute valuing the electrical input signal to obtain an absolute-value electrical signal; log converting the absolute-value electrical signal to obtain a decaying data electrical signal which is a logarithmic value of the absolute-value signal; generating an adjustable reference signal upon the termination of the excitation sound; processing the adjustable reference signal to produce a variable reference decay rate electrical signal; adjusting the reference signal to produce a reference decay rate electrical signal which coincides with the decaying data electrical signal whereby the decay rate characteristics of the enclosure may be determined from the value of the adjusted reference signal.
Claim 14
Independent Claim
157 words
The method of determining sound decay rate of an enclosure which comprises the steps of: exciting the enclosure with sound at a first selected point; terminating the excitation sound imposed on the enclosure; converting the sound decay of the enclosure due to the termination of the excitation sound into an electrical input signal at a second selected point; absolute valuing the electrical input signal to obtain an absolute-value electrical signal; log converting the absolute-value electrical signal to obtain a decaying data electrical signal which is a logarithmic value of the absolute-value signal; generating an adjustable reference signal upon the termination of the excitation sound; processing the adjustable reference signal to produce a variable reference decay rate electrical signal; adjusting the reference signal to produce a reference decay rate electrical signal which coincides with the decaying data electrical signal whereby the decay rate characteristics of the enclosure may be determined from the value of the adjusted reference signal.
Claim 15
Independent Claim
159 words
The method of determining the exponential vibration decay rate of a structure which comprises the steps of: exciting the structure with vibration at a first selected point; terminating the excitation vibration imposed on the structure; converting the vibration decay of the structure due to the termination of the excitation vibration into an electrical input signal at a second selected point; absolute valuing the electrical input signal to obtain an absolute-value electrical signal; log converting the absolute-value electrical signal to obtain a decaying electrical signal which is a logarithmic valve of the absolute value signal; generating an adjustable reference signal upon the termination of the exciting vibration; processing the adjustable reference signal to produce a variable reference decay rate electrical signal; adjusting the reference signal to produce a reference decay rate electrical signal which coincides with the decaying data electrical signal whereby the vibration decay rate of the structure may be determined from the value of the adjusted reference signal.
Claim 16
Independent Claim
159 words
The method of determining the exponential vibration decay rate of a structure which comprises the steps of: exciting the structure with vibration at a first selected point; terminating the excitation vibration imposed on the structure; converting the vibration decay of the structure due to the termination of the excitation vibration into an electrical input signal at a second selected point; absolute valuing the electrical input signal to obtain an absolute-value electrical signal; log converting the absolute-value electrical signal to obtain a decaying electrical signal which is a logarithmic valve of the absolute value signal; generating an adjustable reference signal upon the termination of the exciting vibration; processing the adjustable reference signal to produce a variable reference decay rate electrical signal; adjusting the reference signal to produce a reference decay rate electrical signal which coincides with the decaying data electrical signal whereby the vibration decay rate of the structure may be determined from the value of the adjusted reference signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-02-16 | 1979-08-18 | 1980-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-16 | 1983-08-18 | 1984-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-16 | 1987-08-18 | 1988-02-17 | $7700.00 | Window Closed / Lapsed |