ACOUSTIC SENSOR ASSEMBLY

• US 20150196270A1
• Filed: 03/27/2015
• Published: 07/16/2015
• Est. Priority Date: 12/30/2008
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Masimo Corporation
• Inventors: Telfort, Valery G., Pudar, Predrag, Dimitrov, Dimitar, Trang, Phi, Al-Ali, Ammar
• Granted Patent: US 9,131,917 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2562/0204 Acoustic sensors
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• CPC Class Codes: A61B 5/68335 including release sheets or liners
• CPC Class Codes: A61B 5/6843 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: A61B 7/00 Instruments for auscultation
• CPC Class Codes: A61B 7/003 Detecting lung or respiration noise
• CPC Class Codes: A61B 7/04 Electric stethoscopes microphones, acoustic transducers therefor H04R
• CPC Class Codes: H04R 1/46 Special adaptations for use as contact microphones, e.g. on musical instrument, on stethoscope throat mountings H04R1/14
• CPC Class Codes: H04R 17/025 using a piezoelectric polymer
• CPC Class Codes: Y10T 29/49005 Acoustic transducer

Abstract

An acoustic sensor is configured to provide accurate and robust measurement of bodily sounds under a variety of conditions, such as in noisy environments or in situations in which stress, strain, or movement may be imparted onto a sensor with respect to a patient. Embodiments of the sensor provide a conformable electrical shielding, as well as improved acoustic and mechanical coupling between the sensor and the measurement site.

Claims

1. (canceled)

2. An acoustic sensor assembly comprising:

a frame at least partially defining an open cavity;

a sensing element configured to output a signal responsive to acoustic vibrations, the sensing element supported by the frame, at least a portion of the sensing element comprising a piezoelectric material that is stretched in tension across the open cavity;

electrical contacts electrically coupled with the sensing element and configured to convey an electrical signal corresponding to the signal responsive to the acoustic vibrations;

an acoustic coupler supported by the frame and including an inner protrusion that extends into the open cavity and is positioned to apply pressure to at least the portion of the sensing element that is stretched in tension across the open cavity to push a section of the sensing element into the open cavity both when the acoustic sensor assembly is attached to a medical patient and when the acoustic sensor assembly is not attached to the medical patient, the acoustic coupler configured to transmit acoustic vibrations to the sensing element through the acoustic coupler when the acoustic sensor assembly is attached to the medical patient; and

an elastic portion attached to the frame and extending at least partially beyond opposite sides of the frame, wherein the elastic portion is configured to apply a predetermined force to the frame such that the acoustic sensor assembly is pressed against a measurement site of the medical patient when the acoustic sensor assembly is attached to the medical patient.

3. The acoustic sensor assembly of claim 2, wherein the acoustic coupler further includes an outer protrusion disposed on an outside surface of the acoustic coupler.

4. The acoustic sensor assembly of claim 2, wherein the acoustic coupler electrically isolates the sensing element from the medical patient when the acoustic sensor assembly is attached to the medical patient.

5. The acoustic sensor assembly of claim 2, wherein the acoustic coupler comprises an elastomer.

6. The acoustic sensor assembly of claim 2, wherein the acoustic coupler is configured to evenly distribute pressure on the sensing element.

7. The acoustic sensor assembly of claim 2, wherein the predetermined force is determined at least in part based upon a elasticity of the elastic portion.

8. The acoustic sensor assembly of claim 2, wherein the elastic portion at least partially surrounds the frame when the acoustic sensor assembly is attached to the medical patient.

9. The acoustic sensor assembly of claim 2 further comprising:

a tape portion configured to be attachable to the medical patient so as to attach the acoustic sensor assembly to the medical patient, wherein the elastic portion is attached to the tape portion on a topside of the tape portion, and wherein the elastic portion is attached to a topside of the frame.

10. The acoustic sensor assembly of claim 9, wherein the elastic portion is attached at a middle point of the topside of the tape portion.

11. The acoustic sensor assembly of claim 10, wherein, when the acoustic sensor assembly is attached to the patient, the elastic portion is inclined with respect to the tape portion.

12. The acoustic sensor assembly of claim 2, wherein the elastic portion is permanently affixed to the frame.

13. A method comprising:

using an acoustic sensor assembly according to claim 2, attached to a medical patient, to provide a signal responsive to acoustic vibrations indicative of one or more physiological parameters of the medical patient, the acoustic coupler being in contact with the medical patient; and

outputting the signal based on acoustic vibrations transmitted through the acoustic coupler and detected by the sensing element.

14. The method of claim 13 further comprising using the elastic portion of the acoustic sensor assembly to apply a predetermined force to the frame, wherein the acoustic sensor assembly is pressed against the medical patient.

15. A method of using an acoustic sensor assembly according to claim 2, the acoustic sensor assembly attached to a medical patient via the elastic portion such that the acoustic coupler is pressed against the medical patient, the method comprising:

receiving, via the acoustic coupler, acoustic vibrations;

transmitting, via the acoustic coupler, the received acoustic vibrations to the sensing element;

converting, via the sensing element, the transmitted acoustic vibrations into electrical signals; and

providing the electrical signals to the electrical contacts of the acoustic sensor assembly.

16. The method of claim 15, wherein attaching the acoustic sensor assembly to the medical patient causes the acoustic coupler to further push the section of the sensing element into the open cavity.

17. A method of manufacturing an acoustic sensor assembly, the method comprising:

providing a frame at least partially defining an open cavity;

at least partially supporting, by the frame, a sensing element configured to output a signal responsive to acoustic vibrations, at least a portion of the sensing element comprising a piezoelectric material that is stretched in tension across the open cavity;

providing electrical contacts electrically coupled with the sensing element and configured to convey an electrical signal corresponding to the signal responsive to the acoustic vibrations;

at least partially supporting, by the frame, an acoustic coupler including an inner protrusion that extends into the open cavity and is positioned to apply pressure to at least the portion of the sensing element that is stretched in tension across the open cavity to push a section of the sensing element into the open cavity both when the acoustic sensor assembly is attached to a medical patient and when the acoustic sensor assembly is not attached to the medical patient, the acoustic coupler configured to transmit acoustic vibrations to the sensing element through the acoustic coupler when the acoustic sensor assembly is attached to the medical patient; and

affixing, to the frame, an elastic portion that extends at least partially beyond opposite sides of the frame, wherein the elastic portion is configured to apply a predetermined force to the frame such that the acoustic sensor assembly is pressed against a measurement site of the medical patient when the acoustic sensor assembly is attached to the medical patient.

18. The method of claim 17, wherein the predetermined force is determined at least in part based upon a elasticity of the elastic portion.

19. The method of claim 17, wherein the elastic portion is configured to at least partially surrounds the frame when the acoustic sensor assembly is attached to the medical patient.

20. The method of claim 17 further comprising:

providing a tape portion configured to be attachable to the medical patient so as to attach the acoustic sensor assembly to the medical patient, wherein the elastic portion is attached to the tape portion on a topside of the tape portion, and wherein the elastic portion is attached to a topside of the frame.

21. The method of claim 20, wherein the elastic portion is attached at a middle point of the topside of the tape portion.

22. The method of claim 21, wherein, when the acoustic sensor assembly is attached to the patient, the elastic portion is configured to be inclined with respect to the tape portion.