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US4122427A Expired / Lapsed US ⏱️ 0.0 years remaining

Motion monitor

Assignee: Individual
•
Filing: 1976-06-24
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Granted: 1978-10-24
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Expires: 1996-06-24
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Abstract

Abstract A motion monitor particularly useful for monitoring infant respiration, and comprising an oscillator driving an ultra-sonic wave generator, a receiver for ultra-sonic echoes, a phase detector for detecting phase shift between the outputs of th detector and oscillator and means for recovering the respiration envelope from the output of the phase detector. In a preferred embodiment the system includes a phaselocked loop using selected very low frequencies in the output of the phase detector to control the oscillator frequency.

Inventors

  • 👤 Herbert Karsh

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 12:52
CPC Classifications
G; G01; G01S; G01S15/00; G01S15/02; G01S15/06; G01S15/08; G01S15/32; G01S15/36; A; A61; A61B; A61B5/00; A61B5/103; A61B5/11; A61B5/113; G01S15/50

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 123 words
Apparatus for monitoring substantially cyclic movement of a subject, and comprising, in combination: generating means including a voltage controlled oscillator, for generating a substantially continuous ultrasonic wave and for directing said wave in a beam toward said subject; detecting means for detecting the reflection of said ultrasonic wave from said subject; and means for measuring the path length of said ultrasonic wave from said generating means to said subject and thence to said detection means as a function of the phase difference between the ultrasonic wave generated by said generating means and the ultrasonic wave detected by said detecting means so that substantially cyclic movement of said subject provides phase modulation of the detected ultrasonic wave upon corresponding changes in said path length.
Claim 2
Dependent Claim 123 words
Apparatus for monitoring substantially cyclic movement of a subject, and comprising, in combination: generating means including a voltage controlled oscillator, for generating a substantially continuous ultrasonic wave and for directing said wave in a beam toward said subject; detecting means for detecting the reflection of said ultrasonic wave from said subject; and means for measuring the path length of said ultrasonic wave from said generating means to said subject and thence to said detection means as a function of the phase difference between the ultrasonic wave generated by said generating means and the ultrasonic wave detected by said detecting means so that substantially cyclic movement of said subject provides phase modulation of the detected ultrasonic wave upon corresponding changes in said path length.
Claim 3
Dependent Claim 22 words
Apparatus as defined in claim 1 wherein the output signal of said oscillator is in the range of 35 to 60 KHz.
Claim 4
Dependent Claim 42 words
Apparatus as defined in claim 1 wherein said means for measuring includes a phase detector for providing an output signal the energy content of which is linearly proportional to the phase angle between the output of said oscillator and said detected wave.
Claim 5
Dependent Claim 49 words
Apparatus as defined in claim 3 wherein said voltage controlled oscillator is responsive to a voltage control signal, said apparatus further including a low pass filter coupling the output of said phase detector to said oscillator so that said output signal constitutes said voltage control signal to said oscillator.
Claim 6
Dependent Claim 103 words
Apparatus as defined in claim 1 wherein said oscillator is adapted to provide an output electrical signal, and wherein said detecting means is adapted to provide an electrical output signal, and wherein said means for measuring the path length of said ultrasonic wave comprises an axis crossing detector coupled to receive the electrical signal output from said detecting means, and means for comparing the output of said axis crossing detector with the electrical output of said signal from said oscillator so as to provide a differential signal proportional to the phase difference between the outputs from said axis crossing detector and said oscillator.
Claim 7
Dependent Claim 41 words
Apparatus as defined in claim 5 including switching means for connecting the output signal from the axis crossing detector to said means for comparing only when the amplitude of the output signal from said axis crossing detector exceeds a predetermined value.
Claim 8
Dependent Claim 39 words
Apparatus as defined in claim 5 including a phase locked loop for shifting the output frequency of said generating means so that the phase angle measured by said means for comparing is shifted from any integral value of π.
Claim 9
Dependent Claim 22 words
Apparatus as defined in claim 1 wherein the solid half angle of said beam is within the range of 10° to 20°.
Claim 10
Dependent Claim 23 words
Apparatus according to claim 1, further including means for deriving as a function of said phase modulation the cyclic rate of said movement.
Claim 11
Dependent Claim 39 words
Apparatus as defined in claim 9 wherein said means for deriving said cyclic rate of said movement comprises means for generating single pulses each corresponding to a cycle of said cyclic movement as measured by said means for measuring.
Claim 12
Dependent Claim 62 words
Apparatus as defined in claim 9 wherein said means for measuring comprises a phase detector having an electrical output signal the energy content of which is proportional to the phase angle between said detected wave and said ultrasonic wave, and including a filter coupled between the output of said phase detector and said means for deriving said cyclic rate of said movement.
Claim 13
Dependent Claim 25 words
Apparatus as defined in claim 11 wherein said filter has a band pass characteristic within the range of about 0.33 Hz to about 3.3 Hz.
Claim 14
Dependent Claim 20 words
Apparatus as defined in claim 1 wherein said detecting means comprises a pair of receivers fixedly separated from one another.
Claim 15
Dependent Claim 24 words
Apparatus as defined in claim 1 wherein said function of said phase modulation is a substantially direct linear function between o and π phase.
Claim 16
Dependent Claim 38 words
Apparatus according to claim 1, wherein the wave length of said ultrasonic wave is substantially of the same order of or greater than the magnitude of the expected changes in said path length resulting from said cyclic movement.

References Cited (Backward Citations)

US3550070A Cited
GB1316087A Cited
US3631849A Cited
US3681745A Cited
US3733581A Cited
US3927662A Cited
US3859984A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-23 1982-04-24 1982-10-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-23 1986-04-24 1986-10-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-23 1990-04-24 1990-10-24 $7700.00 Window Closed / Lapsed

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