Transducers with acoustic impedance matching for passive cardio monitoring

• US 20070276251A1
• Filed: 05/02/2006
• Published: 11/29/2007
• Est. Priority Date: 05/02/2006
• Status: Abandoned Application

• Current Assignee: LONO Medical Systems LLC
• Original Assignee: LONO Medical Systems LLC
• Inventors: Orenstein, Nicholas, Rapoport, Ezra
• Application Number:
  US11/417,315
• Publication Number:
  US 20070276251A1
• Time in Patent Office: Days
• US Class Current: 600/459
• CPC Class Codes: A61B 2562/0204 Acoustic sensors
• CPC Class Codes: A61B 5/02411 of foetuses
• CPC Class Codes: A61B 5/4362 Assessing foetal parameters
• CPC Class Codes: A61B 5/6833 Adhesive patches
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal

Abstract

A monitor especially adaptable for fetal heart monitoring receives signals from acoustic transducers each of which includes a base member, a polymer sheet having a pair of electrodes disposed over major, opposing surfaces of the polymer sheet, the polymer sheet disposed adjacent an exterior portion of the base member, a cap affixed to the base member and electrical circuitry carried by the acoustic transducer and coupled to the electrodes on the polymer sheet.

Claims

1. An acoustic transducer comprises:

a base member;

a polymer sheet having a pair of electrodes disposed over major, opposing surfaces of the polymer sheet, the polymer sheet disposed adjacent an exterior portion of the base member;

a cap affixed to the base member; and

electrical circuitry carried by the acoustic transducer and coupled to the electrodes on the polymer sheet.

2. The acoustic transducer of claim 1 wherein the circuitry is disposed between the base and the cap.

3. The acoustic transducer of claim 1 wherein the cap has a convex surface.

4. The acoustic transducer of claim 1 wherein the cap and the base member are secured together.

5. The acoustic transducer of claim 1 wherein base has an aperture and the polymer sheet is supported in the aperture by attaching a securing member to one of the major surfaces of the polymer, the one major surface being on an external surface of the acoustic transducer.

6. The acoustic transducer of claim 1 wherein an exterior surface of the base member has an adhesive layer thereon to adhere the transducer to epidermis of a subject.

7. The acoustic transducer of claim 1 wherein an exterior surface of the base member has an adhesive layer thereon to support an outer one of the major surfaces of the polymer and to adhere the transducer to epidermis of a subject.

8. The acoustic transducer of claim 7 wherein the adhesive layer provides an acoustic impedance coupling between the outer one of the major surfaces of the polymer and epidermis of the subject.

9. The acoustic transducer of claim 1 wherein the adhesive layer is a double-sided tape.

10. The acoustic transducer of claim 1 wherein the circuitry comprises a transmitting device to wirelessly transmit signals from the transducer.

11. The acoustic transducer of claim 1 wherein the circuitry comprises:

a low noise, high impedance amplifier coupled to receive a voltage potential produced across electrodes of the polymer sheet; and

a transmitting device coupled to the output of the amplifier to wirelessly transmit an output signal from the transducer.

12. The acoustic transducer of claim 1 wherein the circuitry comprises circuitry to couple wires or cables to output signals from the transducer.

13. The acoustic transducer of claim 12 wherein the circuitry comprises:

a low noise, high impedance amplifier coupled to receive a voltage potential produced across electrodes of the polymer sheet; and

a connector to couple signals from the amplifier to the wires or cables.

14. The acoustic transducer of claim 5 wherein the aperture in the base member is a generally rectangular aperture in a substantial portion of the base member.

15. The acoustic transducer of claim 5 wherein the aperture in the base member is a generally Y-shaped aperture having three regions, the aperture in a substantial portion of the base member;

and wherein the acoustic transducer comprises;

an additional pair of polymer sheets, with the polymer sheet and the addition pair of polymer sheets disposed in the three regions of the aperture.

16. The acoustic transducer of claim 1 wherein the base member and cover are secured together by a plurality of snap latches on one of the cover and base that mate with receptacles on the other one of the cover and base to secure the base to the cover.

17. The acoustic transducer of claim 1 wherein the transducer body is a round shape.

18. The acoustic transducer of claim 1 wherein the transducer is for heart monitoring.

19. The acoustic transducer of claim 1 wherein the polymer sheet is polyvinyldene fluoride and/or a co-polymer thereof.

20. The acoustic transducer of claim 1 wherein the base and cover are comprised of a relatively strong plastic material that is sufficient in strength to support the weight of a pregnant woman.

21. The acoustic transducer of claim 1 wherein the base and cover are comprised of an ABS plastic any of a class of plastics based on acrylonitrile-butadiene-styrene copolymers.

22. The acoustic transducer of claim 1 wherein the base has an aperture and the polymer member is disposed within the aperture of the base.

23. The acoustic transducer of claim 1 wherein the base has an aperture filled with an acoustic foam materials and the polymer member is disposed within the aperture of the base.

24. The acoustic transducer of claim 1 wherein the polymer member is disposed against the exterior portion of the base.

25. An acoustic transducer comprises:

a base member having an aperture;

a polymer sheet comprised of polyvinyldene fluoride and/or a co-polymer thereof, the sheet having a pair of electrodes disposed over major, opposing surfaces of the sheet, with the sheet disposed in the aperture in the base member;

a cap affixed to the base member; and

electrical circuitry disposed in the acoustic transducer and electrically coupled to the electrodes on the sheet.

26. The acoustic transducer of claim 25 wherein the circuitry comprises a transmitter to transmit signals from the polymer sheet.

27. The acoustic transducer of claim 25 wherein the circuitry comprises:

a low noise, high impedance amplifier coupled to receive a voltage potential produced across electrodes of the sheet; and

a transmitting device coupled to the amplifier to wirelessly transmit an output signal from the amplifier.

28. The acoustic transducer of claim 25 wherein the cap has a convex surface.

29. The acoustic transducer of claim 25 wherein the sheet is supported in the aperture by attaching an adhesive to one of the major surfaces of the polymer, the one major surface being on an external surface of the acoustic transducer.

30. The acoustic transducer of claim 25 wherein the adhesive layer adheres the transducer to epidermis of a subject.

31. The acoustic transducer of claim 25 wherein the adhesive layer provides an acoustic impedance coupling between the outer one of the major surfaces of the polymer and epidermis of the subject.

32. The acoustic transducer of claim 25 wherein the adhesive layer is a double-sided tape.

33. The acoustic transducer of claim 25 wherein the circuitry comprises circuitry to couple wires or cables to output signals from the transducer.

34. The acoustic transducer of claim 25 wherein the circuitry comprises:

a low noise, high impedance amplifier coupled to receive a voltage potential produced across electrodes of the sheet; and

a connector to couple signals from the amplifier to the wires or cables.

35. The acoustic transducer of claim 25 wherein the aperture in the base member is a generally rectangular aperture in a substantial portion of the base member.

36. The acoustic transducer of claim 25 wherein the aperture in the base member is a generally Y-shaped aperture having three regions, the aperture in a substantial portion of the base member;

and wherein the acoustic transducer comprises;

an additional pair of polymer sheets, with the polymer sheet and the addition pair of polymer sheets disposed in the three regions of the aperture.

37. The acoustic transducer of claim 25 wherein the transducer is for heart monitoring.

38. The acoustic transducer of claim 25 wherein the base and cover are comprised of a relatively strong plastic material that is sufficient in strength to support the weight of a pregnant woman.

39. The acoustic transducer of claim 25 wherein the base and cover are comprised of an ABS plastic any of a class of plastics based on acrylonitrile-but-adiene-styrene copolymers.

40. The acoustic transducer of claim 25 wherein the base has an aperture filled with an acoustic foam materials and the sheet is disposed within the aperture of the base.