US3665754A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus to prevent mismeasuring of wall thickness gauging by ultrasound
Assignee: Individual
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Filing: 1968-10-11
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Granted: 1972-05-30
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Expires: 1988-10-11
Abstract
Abstract Method and apparatus are disclosed for preventing mismeasurement when gauging wall thickness by an ultrasonic pulse echo transit time method using separate transmitter and receiver probes. The pulse transit time, in the specimen plus a fixed known period of time is taken as the gauging value. Cross talk, i.e., an echo from the probe-to-specimen interface, is prevented from causing mismeasurements of thin wall specimens by providing an electronic gate which is opened during the cross talk time interval for receiving cross talk pulses having an amplitude over a predetermined lower threshold value to actuate a mismeasurement warning light or to prevent the gauge from indicating wall thickness.
Inventors
- 👤 Herbert Krautkramer
- 👤 Joseph Krautkramer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:34
CPC Classifications
G; G01; G01B; G01B17/00; G01B17/02; G01S; G01S15/00; G01S15/02; G01S15/06; G01S15/08; G01S15/10; G01S15/101
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
141 words
In a pulsed ultrasonic measuring apparatus for measuring the wall thickness of specimens, means forming a transmitter probe for transmitting ultrasonic pulses into a specimen to be measured, means forming a receiver probe for receiving echo pulses from the specimen, means for measuring the transit time of the received echo pulses in the specimen for measuring wall thickness of the specimen, the improvement comprising, means for sensing the pulse height of echo pulses received within a certain cross talk transit time interval corresponding to echo pulses reflected from the input face of the specimen to derive an output if the cross talk echo pulse exceeds a certain predetermined pulse height, and means responsive to the output of said pulse height level sensor for preventing erroneous measurements of wall thickness if the cross talk echo pulse exceeds the certain predetermined pulse height.
Claim 2
Dependent Claim
141 words
In a pulsed ultrasonic measuring apparatus for measuring the wall thickness of specimens, means forming a transmitter probe for transmitting ultrasonic pulses into a specimen to be measured, means forming a receiver probe for receiving echo pulses from the specimen, means for measuring the transit time of the received echo pulses in the specimen for measuring wall thickness of the specimen, the improvement comprising, means for sensing the pulse height of echo pulses received within a certain cross talk transit time interval corresponding to echo pulses reflected from the input face of the specimen to derive an output if the cross talk echo pulse exceeds a certain predetermined pulse height, and means responsive to the output of said pulse height level sensor for preventing erroneous measurements of wall thickness if the cross talk echo pulse exceeds the certain predetermined pulse height.
Claim 3
Dependent Claim
28 words
The apparatus of claim 1 including, a gate circuit for gating echo pulses falling within the certain cross talk transit time interval to said erroneous measurement prevention means.
Claim 4
Dependent Claim
26 words
The apparatus of claim 2 wherein said erroneous measurement prevention means includes, a warning light actuated by the gated output of said pulse height level sensor.
Claim 5
Dependent Claim
24 words
The apparatus of claiM 2 wherein said means for preventing erroneous measurement includes means for blocking operation of said pulse transit time measuring means.
Claim 6
Dependent Claim
55 words
The apparatus of claim 4 wherein said pulse transit time measuring means includes a pointer instrument for indicating the wall thickness, and means for applying the output signals from said gate circuit to said pointer instrument means for causing the pointer of said pointer instrument means to point to an off measurement scale portion thereof.
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) | 1975-05-30 | 1975-11-29 | 1976-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-30 | 1979-11-29 | 1980-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-30 | 1983-11-29 | 1984-05-30 | $7700.00 | Window Closed / Lapsed |