US3898838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultrasonic scanning system
Assignee: Navistar International Corp
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Filing: 1973-11-01
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Granted: 1975-08-12
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Expires: 1993-11-01
Abstract
Abstract Ultrasonic scanning system in which the angular position of a transducer is alternately adjusted about two transverse axes by reversible stepping motors each being adjusted by operating in one direction until obtaining a decrease in the amplitude of a front surface reflection signals, gated to a sample/hold circuit, the direction being reversed to increase the amplitude of the front surface reflection signal to a maximum and to thereby position the axis of the transducer normal to the front surface of a part under test. Another stepping motor is operated to hold a transducer toward or away from the part in response to outputs from sample/hold circuits to which a received video signal is gated during time intervals respectively greater than and less than a time corresponding to a desired spacing, to thereby maintain a substantially fixed distance between a transducer and the part.
Inventors
- 👤 John J Connelly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:58
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/22; G01N29/26; G01N29/265
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
179 words
In an ultrasonic testing system including transducer means for periodically transmitting bursts of ultrasonic energy toward a front surface of a part and for developing a test signal including a front surface signal from reflection from said front surface and additional signals from reflections from inhomogeneities within the part, scanning means including reversible electric motor means for adjusting the angular position of said transducer means about a predetermined axis, means for supplying a clock signal in synchronized relation to the transmission of a burst from said transducer means, and angular adjustment means responsive to said front surface signal for controlling said reversible electric motor means to rotate said transducer means about a predetermined axis to increase the amplitude of said front surface signal toward a maximum value, said angular adjustment means comprising gating means, means responsive to said clock signal for operating said gating means fOr a time interval starting at a time before said front surface signal and ending at a time after said front surface signal, and means for applying said test signal to said gating means.
Claim 2
Dependent Claim
179 words
In an ultrasonic testing system including transducer means for periodically transmitting bursts of ultrasonic energy toward a front surface of a part and for developing a test signal including a front surface signal from reflection from said front surface and additional signals from reflections from inhomogeneities within the part, scanning means including reversible electric motor means for adjusting the angular position of said transducer means about a predetermined axis, means for supplying a clock signal in synchronized relation to the transmission of a burst from said transducer means, and angular adjustment means responsive to said front surface signal for controlling said reversible electric motor means to rotate said transducer means about a predetermined axis to increase the amplitude of said front surface signal toward a maximum value, said angular adjustment means comprising gating means, means responsive to said clock signal for operating said gating means fOr a time interval starting at a time before said front surface signal and ending at a time after said front surface signal, and means for applying said test signal to said gating means.
Claim 3
Dependent Claim
80 words
In a system as defined in claim 1, said scanning means including second reversible electric motor means for adjusting the angular position of said transducer means about a second predetermined axis generally transverse to said first predetermined axis, and second angular adjustment means responsive to said front surface signal for controlling said second reversible electric motor means to rotate said transducer means about said second predetermined axis to increase the amplitude of said front surface signal toward a maximum value.
Claim 4
Dependent Claim
23 words
In a system as defined in claim 2, means for alternately operating the first angular adjustment means and said second angular adjustment means.
Claim 5
Dependent Claim
87 words
In a system as defined in claim 1, said angular adjustment means comprising means for energizing said motor means in an arbitrarily determined direction, means for continuing energization of said motor means in said direction when the amplitude of a front surface signal is greater than the amplitude of a preceding front surface signal, and means for discontinuing energization of said motor means in said direction when the amplitude of a front surface signal is less than the amplitude of that of a preceding front surface signal.
Claim 6
Dependent Claim
37 words
In a system as defined in claim 4, means for energizing said motor means in the reverse direction when the amplitude of a front surface signal is less than the amplitude of a preceding front surface signal.
Claim 7
Dependent Claim
47 words
In a system as defined in claim 1, holding means associated with said gating means to develop an output signal held at the level of the peak amplitude of a front surface signal applied thereto until application of another front surface signal of a different peak amplitude.
Claim 8
Dependent Claim
64 words
In a system as defined in claim 6, second holding means coupled to the output of a first holding means to develop an output signal held at the level of the output of the first holding means until after a new level is established by said first holding means, and comparator means to compare the output levels of said first and second holding means.
Claim 9
Dependent Claim
76 words
In a system as defined in claim 7, flip-flop means, means coupled to said comparator means and to said flip-flop means for triggering said flip-flop means to an opposite state when the output level of said first holding means is less than the output of said second holding means, and means coupled to said flip-flop means for controlling the direction of operation of said reversible motor means in accordance with the state of said flip-flop means.
Claim 10
Dependent Claim
87 words
In a system as defined in claim 1, said scanning means including means for moving said transducer means in a path in generally parallel relation to said front surface and further including additional reversible electric motor means for moving said transducer means toward and away from said front surface, and spacing adjustment means responsive to said clock signal and said front surface signal for controlling said additional reversible electric motor means to maintain a predetermined spacing between said transducer means and said front surface of the part.
Claim 11
Dependent Claim
142 words
In an ultrasonic testing system including transducer means for periodically transmitting bursts of ultrasonic energy toward a front surface of a part and for developing a test signal including a front surface signal from reflections from said front surface and additional signals from reflections from inhomogeneities within the part, scanning means including means for moving said transducer means in a path in generally parallel relation to said front surface and reversible electric motor means for moving said transducer means toward and away from said front surface, means for supplying a clock signal in synchronized relation to the transmission of bursts from said transducer means, and spacing adjustment means responsive to said clock signals and said front surface signal for controlling said reversible electric motor means to maintain a predetermined fixed spacing between said transducer means and said front surface of the part.
Claim 12
Dependent Claim
142 words
In an ultrasonic testing system including transducer means for periodically transmitting bursts of ultrasonic energy toward a front surface of a part and for developing a test signal including a front surface signal from reflections from said front surface and additional signals from reflections from inhomogeneities within the part, scanning means including means for moving said transducer means in a path in generally parallel relation to said front surface and reversible electric motor means for moving said transducer means toward and away from said front surface, means for supplying a clock signal in synchronized relation to the transmission of bursts from said transducer means, and spacing adjustment means responsive to said clock signals and said front surface signal for controlling said reversible electric motor means to maintain a predetermined fixed spacing between said transducer means and said front surface of the part.
Claim 13
Dependent Claim
164 words
In a system as defined in claim 10, said spacing adjustment means comprising first and second gating means, means for operating said first gating means for a time interval starting in a first time substantially after transmission of a burst from said transducer means and ending at a second time after said first time, means for operating said second gating means starting at a third time after said second time and ending at a fourth time after said third time, means for supplying said test signal to said first and second gate means, firsst control means responsive to the gating of a front surface signal through said first gate means for energizing said motor means in a first direction to move said transducer means away from said front surface, and second control means responsive to the gating of a front surface signal through said second gating means for energizing said motor in an opposite direction to move said transducer means toward said front surface.
Claim 14
Dependent Claim
53 words
In a system as defined in claim 11, first andd second holding means associated with said first and second gating means and each arranged to develop an ouput signal held at the level of the peak amplitude of a pulse applied thereto until application of another pulse of a different peak amplitude thereto.
Claim 15
Dependent Claim
122 words
In a system as defined in claim 12, said first control means comprising means for supplying a first reference voltage, and first comparator means for comparing said first reference voltage in the output of said first holding means to develop a first output signal when the output of said first holding means exceeds said first reference voltage, said second control means comprising means for supplying a second reference voltage and second comparator means for comparing said second reference voltage and the output of said second holding means to develop a second means exceeds said second reference voltage, and first and second energizing means for energizing said motor in opposite first and second directions in response to said first and second output signals.
Claim 16
Dependent Claim
30 words
In a system as defined in claim 13, said first and second energizing means comprising first and second relays responsive to the outputs of said first and second comparator circuits.
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) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |