US3836948A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Echo sounding technique
Assignee: F Hoffmann La Roche AG
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Filing: 1973-02-07
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Granted: 1974-09-17
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Expires: 1993-02-07
Abstract
Abstract An ultrasonic echo sounding technique for reducing echoes from reflectors outside the field of interest comprising: a substantially annular ultrasonic transducer assembly having a plurality of equally sized segmental transducer elements whose radiation surfaces are inclined towards the annular axis; a transmitter with a generator; phase shifting means for driving selected transducer elements with signals having relative phase shift; transmitter switches for optionally switching the aforementioned apparatus between generator and transducer to produce first and second waves; a receiver with a first and second adder; phase rotation means connected with said second adder; receiver switches operated in synchronism with the transmitter switches for optionally switching the transducer elements between the phase rotation means and first adder; rectifier means for rectifying the outputs of the adders; a delay line for delaying signals from the first adder; and, subtraction means for taking the difference of the first and second adder outputs and displaying the results.
Inventors
- 👤 C Burckhardt
- 👤 P Grandchamp
- 👤 H Hoffmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:48
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/52; G01S7/52003; G01S15/00; G10; G10K; G10K11/00; G10K11/18; G10K11/26; G10K11/34; G10K11/341; G10K11/346; Y; Y10; Y10S; Y10S367/00; Y10S367/901; Y10S367/905
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
123 words
In an ultrasonic echo sounding technique a method for reducing echoes from reflectors outside a focal line with ultrasonic waves having substantially identical travel times comprising: generating a first convergent ultrasonic wave of substantially annular cross-section in phase over the entire cross-section; deriving from reflected ultrasonic echoes from the first wave a first set of electrical signals; generating a second convergent ultrasonic wave of substantially annular cross-section out of phase over the entire cross-section; deriving from reflected ultrasonic echoes from the second wave a second set of electrical signals; modifying the second set of electrical signals with phase correcting coefficients; and, comparing said first and second sets of electrical signals to provide a resultant signal indicative of the reflector at the focal line.
Claim 2
Dependent Claim
123 words
In an ultrasonic echo sounding technique a method for reducing echoes from reflectors outside a focal line with ultrasonic waves having substantially identical travel times comprising: generating a first convergent ultrasonic wave of substantially annular cross-section in phase over the entire cross-section; deriving from reflected ultrasonic echoes from the first wave a first set of electrical signals; generating a second convergent ultrasonic wave of substantially annular cross-section out of phase over the entire cross-section; deriving from reflected ultrasonic echoes from the second wave a second set of electrical signals; modifying the second set of electrical signals with phase correcting coefficients; and, comparing said first and second sets of electrical signals to provide a resultant signal indicative of the reflector at the focal line.
Claim 3
Dependent Claim
43 words
A method according to claim 1 including providing each second wave generated with a predetermined phase shift pattern over the entire cross-section, and providing said phase correcting coefficients with values identical to that applied during the generating step but having a reversed sign.
Claim 4
Dependent Claim
22 words
A method according to claim 1 including storing the derived first set of signals until said second set of signals are derived.
Claim 5
Dependent Claim
30 words
A method according to claim 1 where the phase of each successive generated ultrasonic second wave is uniformly proportioned at each point defined by angle phi of their respective cross-sections.
Claim 6
Dependent Claim
17 words
A method according to claim 4 whereby the phase is k phi , k being an integer.
Claim 7
Dependent Claim
9 words
A method according to claim 5 whereby k 2.
Claim 8
Dependent Claim
31 words
A method according to claim 4 whereby phi assumes a number of discrete values so that the phase of each in the ultrasonic second waves varies in steps over the cross-section.
Claim 9
Dependent Claim
21 words
A method according to claim 7 whereby integral multiples of the discrete values of phi are equal to 2 pi .
Claim 10
Dependent Claim
22 words
A method according to claim 7 whereby the stepped change is obtained by phase shift in each the generated ultrasonic second waves.
Claim 11
Dependent Claim
145 words
Ultrasonic echo sounding apparatus for reducing echoes from reflectors outside a focal line with ultrasonic waves having substantially identical travel times comprising: annular assembly means having a plurality of identically sized segmental ultrasonic transducer means whose radiation surfaces are inclined towards an axis defined by the annular assembly means; generator means for driving said transducers; phase shift means adapted for connection between said generator means and transducer means; receiver means including a first and second adding means; said second adding means including phase rotation delay means; switch means operative in a first position for connecting said transducer means with said generator means and said first adding means, and in a second position for connecting said transducer means with said generator means through said phase shift means and said second adding means; and, means for comparing the output of said delay means and second adding means.
Claim 12
Dependent Claim
145 words
Ultrasonic echo sounding apparatus for reducing echoes from reflectors outside a focal line with ultrasonic waves having substantially identical travel times comprising: annular assembly means having a plurality of identically sized segmental ultrasonic transducer means whose radiation surfaces are inclined towards an axis defined by the annular assembly means; generator means for driving said transducers; phase shift means adapted for connection between said generator means and transducer means; receiver means including a first and second adding means; said second adding means including phase rotation delay means; switch means operative in a first position for connecting said transducer means with said generator means and said first adding means, and in a second position for connecting said transducer means with said generator means through said phase shift means and said second adding means; and, means for comparing the output of said delay means and second adding means.
Claim 13
Dependent Claim
29 words
Apparatus according to claim 10 wherein the phase shift means comprises a delay line which is tapped at regular intervals for connection to preselected ones of said transducer means.
Claim 14
Dependent Claim
23 words
Apparatus according to claim 10 including: rectifier means connected from each of said adding means; and indicating means connected from said comparison means.
Claim 15
Dependent Claim
34 words
Apparatus according to claim 10 whereby said ultrasonic transducer means includes twelve transducer elements commonly connected in groups of two through the switch means for being driven and delivering signals to the receiver means.
Claim 16
Dependent Claim
33 words
Apparatus according to claim 13 whereby the outputs of the phase shift means have a relative phase difference of 60* and the phase rotation means apply the same phase shift with reVersed sign.
Claim 17
Dependent Claim
66 words
Apparatus according to claim 11 whereby the rectifier means includes first and second multiplier means for respectively multiplying their output signals by cos omega t and sin omega t; first and second low pass filters respectively connected from said multiplier means for eliminating the frequencies close to the transmission frequency; and, circuit means for forming the root from the sum of the squares of their imputs.
Claim 18
Dependent Claim
186 words
Ultrasonic echo sounding apparatus for reducing echoes from reflectors outside a focal line with ultrasonic waves having substantially identical travel times comprising: transmitter means; first, second and third annular ultrasonic transducer with annular radiation surfaces means having a common annulus axis; said first transducer means having a radiation surface inclined relative to said axis with edges disposed substantially in a plane perpendicular to the axis; said second transducer means having a radiation surface with edges disposed on a helical surface forming a raised portion with respect to said plane; said third transducer means having a radiation surface with edges disposed on a helical surface representing an indentation with respect to said plane; signal processing means; delay line means; subtraction means; indicating means connected from the subtraction means; and, switch means connecting in one position the first transducer means with said transmitter means and the signal processing means to the delay line means and thence to the subtraction means, and connecting in a second position the second transducer means to the transmitter means and the third transducer means directly to the subtraction means via said processing means.
Claim 19
Dependent Claim
186 words
Ultrasonic echo sounding apparatus for reducing echoes from reflectors outside a focal line with ultrasonic waves having substantially identical travel times comprising: transmitter means; first, second and third annular ultrasonic transducer with annular radiation surfaces means having a common annulus axis; said first transducer means having a radiation surface inclined relative to said axis with edges disposed substantially in a plane perpendicular to the axis; said second transducer means having a radiation surface with edges disposed on a helical surface forming a raised portion with respect to said plane; said third transducer means having a radiation surface with edges disposed on a helical surface representing an indentation with respect to said plane; signal processing means; delay line means; subtraction means; indicating means connected from the subtraction means; and, switch means connecting in one position the first transducer means with said transmitter means and the signal processing means to the delay line means and thence to the subtraction means, and connecting in a second position the second transducer means to the transmitter means and the third transducer means directly to the subtraction means via said processing means.
References Cited (Backward Citations)
US3086195A
Cited
US3341807A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-16 | 1978-03-18 | 1978-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-16 | 1982-03-18 | 1982-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-16 | 1986-03-18 | 1986-09-17 | $7700.00 | Window Closed / Lapsed |