US3780725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fetal heartbeat monitoring system with plural transducers in one plane and at different angles thereto
Assignee: SmithKline Instrument Inc
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Filing: 1971-03-04
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Granted: 1973-12-25
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Expires: 1991-03-04
Abstract
Abstract Fetal heartbeat monitoring system in which a plurality of ultrasonic beams are transmitted at different angles into the uterus of an expectant mother. A plurality of receiving transducers are inclined at different angles for receiving the signal as it is reflected from the fetus and/or uterus walls, the frequency of the reflected signal differing from that of the transmitted signal by an amount corresponding to the rate of the fetal heart motion. A system of rate computation from the resultant doppler fetal heart motion signal is employed which utilizes frequency domain techniques. The heart rate signal is extracted from the doppler heart motion signal by means of a diode demodulator and low frequency band pass filter.
Inventors
- 👤 P Goldberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 00:35
CPC Classifications
A; A61; A61B; A61B8/00; A61B8/02; A61B5/00; A61B5/05; A61B5/0507; A61B8/08; A61B8/0866
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
170 words
In a system for monitoring the heart-beat of a fetus in the womb of an expectant mother, a transducer assembly including a generally planar surface, strap means for holding the assembly in a predetermined position on the outer abdominal wall of an expectant mother, said transducer assembly including a plurality of transducer elements mounted in a single plane and inclined at predetermined angles relative to the generally planar surface for transmitting energy into the womb of the expectant mother and receiving energy reflected from within the womb in discrete beams, said beams intersecting each other in an elongated region extending along an axis normal to the planar surface, the reflected energy having a fetal heart rate component which differs in frequency from the transmitted energy by an amount corresponding to the rate of fetal heart movement, signal generating means connected to some of said transducer elements, and means connected to others of said transducer elements for processing signals received thereby to recover the fetal heart rate component of said signals.
Claim 2
Dependent Claim
170 words
In a system for monitoring the heart-beat of a fetus in the womb of an expectant mother, a transducer assembly including a generally planar surface, strap means for holding the assembly in a predetermined position on the outer abdominal wall of an expectant mother, said transducer assembly including a plurality of transducer elements mounted in a single plane and inclined at predetermined angles relative to the generally planar surface for transmitting energy into the womb of the expectant mother and receiving energy reflected from within the womb in discrete beams, said beams intersecting each other in an elongated region extending along an axis normal to the planar surface, the reflected energy having a fetal heart rate component which differs in frequency from the transmitted energy by an amount corresponding to the rate of fetal heart movement, signal generating means connected to some of said transducer elements, and means connected to others of said transducer elements for processing signals received thereby to recover the fetal heart rate component of said signals.
Claim 3
Dependent Claim
62 words
A system as in claim 1 wherein said transducer elements are provided in pairs, each of said pairs including one transmitting element and one receiving element, the elements in different pairs being inclined at different angles relative to said generally planar surface so that the beams associated with different pairs intersect along the axis at different distances from the generally planar surface.
Claim 4
Dependent Claim
20 words
A system as in claim 1 together with means for converting the fetal heart rate component to an analog signal.
Claim 5
Dependent Claim
17 words
A system as in claim 1 together wih controlled gain amplifier means for amplifying the reflected signal.
Claim 6
Dependent Claim
64 words
A system as in claim 1 wherein the means for processing the received signals includes means for translating the frequency of the reflected signal so that said signal has a predetermined center frequency, bandpass filter means for separating the fetal heart rate component from the remainder of the frequency translated signal, and means for converting the fetal heart rate component to a pulsating signal.
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) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |