US3975939A
Expired / Lapsed
US
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Methods of and apparatus for simulating ultrasonic pulse echoes
Assignee: Individual
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Filing: 1975-07-02
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Granted: 1976-08-24
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Expires: 1995-07-02
Abstract
Abstract Methods of and apparatus for simulating ultrasonic pulse echoes are used to test and calibrate ultrasonic flaw detectors by simulating a train of radio frequency pulses, having a pulse repetition frequency which is indicative of both the speed of sound in a material under test and the thickness of that material. This is accomplished by generating a train of d.c. pulses having a pulse repetition frequency, which is directly proportional to and, which is a multiple of the speed of sound of the material The pulse repetition frequency is also inversely proportional to the thickness of the material. The d.c. pulses are used to drive a radio frequency pulse generator and a pulse modulator. The outputs of the radio frequency generator and pulse modulator are then combined to produce a signal having an amplitude envelope, which simulates a series of ultrasonic pulse echoes.
Inventors
- 👤 Archibald Joseph McLean
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:12
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/22; G01N29/30
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
146 words
A method of simulating an ultrasonic signal corresponding to a material under test in order to test circuitry of an ultrasonic test set, comprising the steps of: generating an initial pulse, generating a train of d.c. pulses in response to said initial pulse, the pulse repetition frequency of the d.c. pulses being inversely proportional to the thickness of the material being simulated and directly proportional to the speed of sound in the material being simulated, generating a radio frequency pulse with each d.c. pulse to produce a series of radio frequency pulses having a pulse repetition frequency of the d.c. pulses, shaping each radio frequency pulse to resemble those generated by an ultrasonic transducer; and modulating the amplitude of successive radio frequency pulses to produce a series of radio frequency pulses, which are selectively equal in amplitude, linearly declining in amplitude, or logarithmically declining in amplitude.
Claim 2
Independent Claim
146 words
A method of simulating an ultrasonic signal corresponding to a material under test in order to test circuitry of an ultrasonic test set, comprising the steps of: generating an initial pulse, generating a train of d.c. pulses in response to said initial pulse, the pulse repetition frequency of the d.c. pulses being inversely proportional to the thickness of the material being simulated and directly proportional to the speed of sound in the material being simulated, generating a radio frequency pulse with each d.c. pulse to produce a series of radio frequency pulses having a pulse repetition frequency of the d.c. pulses, shaping each radio frequency pulse to resemble those generated by an ultrasonic transducer; and modulating the amplitude of successive radio frequency pulses to produce a series of radio frequency pulses, which are selectively equal in amplitude, linearly declining in amplitude, or logarithmically declining in amplitude.
Claim 3
Dependent Claim
30 words
The method of claim 1 further including the step of stopping the pulses, after a predetermined number have been generated to await another initial pulse to start the series anew.
Claim 4
Dependent Claim
33 words
The method of claim 2 further including the step of: delaying between generating the initial pulse and generating the train of d.c. pulses, in order to simulate a material immersed in a liquid.
Claim 5
Dependent Claim
173 words
Apparatus for simulating an electrical signal produced by an ultrasonic transducer monitoring a material said apparatus comprising: means for applying an input pulse to said apparatus to initiate operation of said apparatus, clock means for generating a train of d.c. pulses the frequency of which is directly proportional to the speed of sound of the material, frequency dividing means for dividing the frequency of the train of d.c. pulses to produce an output the frequency of which is inversely proportional to the thickness of the material, radio frequency pulse generating means driven at the pulse repetition frequency of the frequency dividing means to produce a train of radio frequency pulses, means for shaping each radio frequency pulse to resemble those generated by an ultrasonic transducer, means for modulating the train of pulses from the radio frequency pulse generator to selectively produce trains of radio frequency pulses, which are equal in amplitude, linearly declining in amplitude, and logarithmically declining in amplitude, and means for applying said radio frequency pulses to said circuit under test.
Claim 6
Dependent Claim
173 words
Apparatus for simulating an electrical signal produced by an ultrasonic transducer monitoring a material said apparatus comprising: means for applying an input pulse to said apparatus to initiate operation of said apparatus, clock means for generating a train of d.c. pulses the frequency of which is directly proportional to the speed of sound of the material, frequency dividing means for dividing the frequency of the train of d.c. pulses to produce an output the frequency of which is inversely proportional to the thickness of the material, radio frequency pulse generating means driven at the pulse repetition frequency of the frequency dividing means to produce a train of radio frequency pulses, means for shaping each radio frequency pulse to resemble those generated by an ultrasonic transducer, means for modulating the train of pulses from the radio frequency pulse generator to selectively produce trains of radio frequency pulses, which are equal in amplitude, linearly declining in amplitude, and logarithmically declining in amplitude, and means for applying said radio frequency pulses to said circuit under test.
Claim 7
Dependent Claim
39 words
The apparatus of claim 4 including means for counting said pulses and means for stopping said clock means after a predetermined number of pulses to thereby produce an identical radio frequency pulse train in response to each input pulse.
Claim 8
Dependent Claim
30 words
The apparatus of claim 4 wherein said means for applying an input includes means for delaying application of said input pulse to simulate the material being immersed in a liquid.
Claim 9
Dependent Claim
19 words
The apparatus of claim 4 further including indicating means for visually displaying the speed of sound of the material.
Claim 10
Dependent Claim
35 words
The apparatus of claim 4 wherein the means for modulating the train of pulses includes a step counter, a read only memory and a selection means for determining the amplitude of the radio frequency pulses.
Claim 11
Independent Claim
175 words
A method of simulating an ultrasonic signal corresponding to a material under test in order to test set, said method comprising the steps of: generating an initial pulse, generating a train of d.c. pulses in response to said initial pulse, wherein said d.c. pulses have a pulse repetition frequency, which is directly proportional to the speed of sound in the material, dividing the frequency of the d.c. pulses by a factor proportional to the thickness of the material to produce a subsequent train of d.c. pulses having a pulse repetition frequency inversely proportional to the thickness of the material, generating a radio frequency pulse with each pulse of the subsequent train to produce a series of radio frequency pulses having the pulse repetition frequency of the subsequent train of pulses, shaping each radio frequency pulse to resemble those generated by an ultrasonic transducer, and modulating the amplitude of successive radio frequency pulses to produce a series of radio frequency pulses, which are selectively equal in amplitude, linearly declining in amplitude, or logarithmically declining in amplitude.
Claim 12
Independent Claim
175 words
A method of simulating an ultrasonic signal corresponding to a material under test in order to test set, said method comprising the steps of: generating an initial pulse, generating a train of d.c. pulses in response to said initial pulse, wherein said d.c. pulses have a pulse repetition frequency, which is directly proportional to the speed of sound in the material, dividing the frequency of the d.c. pulses by a factor proportional to the thickness of the material to produce a subsequent train of d.c. pulses having a pulse repetition frequency inversely proportional to the thickness of the material, generating a radio frequency pulse with each pulse of the subsequent train to produce a series of radio frequency pulses having the pulse repetition frequency of the subsequent train of pulses, shaping each radio frequency pulse to resemble those generated by an ultrasonic transducer, and modulating the amplitude of successive radio frequency pulses to produce a series of radio frequency pulses, which are selectively equal in amplitude, linearly declining in amplitude, or logarithmically declining in amplitude.
References Cited (Backward Citations)
US2796756A
Cited
US2966057A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-24 | 1980-02-23 | 1980-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-24 | 1984-02-23 | 1984-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-24 | 1988-02-23 | 1988-08-24 | $7700.00 | Window Closed / Lapsed |