Resonant Multilayered Impedance Pump

• US 20070177997A1
• Filed: 01/08/2007
• Published: 08/02/2007
• Est. Priority Date: 01/06/2006
• Status: Active Grant

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Gharib, Morteza, Hickerson, Anna, Forouhar, Arian, Rinderknecht, Derek, Loumes, Laurence
• Granted Patent: US 8,092,365 B2
• Time in Patent Office: Days
• US Class Current: 417/394
• CPC Class Codes: A61M 2205/0283 Electro-active polymers [EAP]
• CPC Class Codes: A61M 60/139 inside the aorta, e.g. intra-aortic balloon pumps
• CPC Class Codes: A61M 60/148 in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices
• CPC Class Codes: A61M 60/427 the force acting on the blood contacting member being hydraulic or pneumatic
• CPC Class Codes: A61M 60/454 generated by electro-active actuators, e.g. using electro-active polymers or piezoelectric elements
• CPC Class Codes: A61M 60/462 Electromagnetic force
• CPC Class Codes: F04B 43/08 having tubular flexible members F04B43/12 takes precedence
• CPC Class Codes: F04B 43/10 Pumps having fluid drive
• CPC Class Codes: F04F 7/00 Pumps displacing fluids by using inertia thereof, e.g. by generating vibrations therein

Abstract

A multilayered impedance pump is formed by an inner tube and an outer tube which have different mechanical characteristics. The outer tube is relatively stiff, and can be used for a structural material. The inner tube is excitable, and a gel is placed between the inner and outer tube. The actuator actuates the gel to cause pressure waves along the inner tube.

Claims

1. A pumping device, comprising:

an outer lumen, formed of a substantially unbending material defining an inner surface inside the lumen, and an outer surface outside the lumen;

an inner lumen, formed entirely within said inner surface within the outer lumen, said inner lumen formed of a material that is elastically deformable and having an inside surface which is adapted to receive a fluid therein;

a fluid material, between said inner wall and said outer wall, said fluid material having a mechanical property that allows it to transmit applied force waves; and

an actuator, that actuates said fluid material at a frequency that causes constructive wave interaction within the fluid material and drives a fluid flow through the inside surface of the inner lumen.

2. A device as in claim 1, further comprising another section, connected to said inner lumen, where said another section has a different fluidic characteristic than said inner lumen.

3. A device as in claim 1, further comprising a controller, that controls the actuator to produce an lower amplitude actuation of said material at a frequency that produces a higher amplitude actuating of said inner lumen.

4. A device as in claim 1, wherein said actuator is located between said inner lumen and said outer lumen.

5. A device as in claim 4, wherein said actuator is located within the fluid material.

6. A device as in claim 1, wherein at least one of said inner lumen and said outer lumen has a closed end.

7. A device as in claim 1, wherein at least one of said inner lumen and said outer lumen have open ends.

8. A device as in claim 1, wherein said fluid material is a hydrogel.

9. A device as in claim 3, wherein said actuator controls the lower amplitude waves to a frequency that constructively interfere, to create the higher amplitude wave.

10. A device as in claim 9, wherein said higher amplitude wave is used to form a surface wave on said inner lumen.

11. A device as in claim 3, wherein said actuator controls the lower amplitude waves to a frequency that causes a resonant effect in the fluid material, to create a higher amplitude wave.

12. A device as in claim 11, wherein said higher amplitude wave is used to form a surface wave on said inner lumen.

13. A device as in claim 1, wherein said fluid material has the viscosity of a gel.

14. A device as in claim 1, wherein said inner and outer lumens are each substantially cylindrical.

15. A method comprising:

pumping using a device that has an outer lumen, formed of a substantially unbending material, an inner lumen, formed entirely within an inside defined within the outer lumen, formed of a material that is elastically deformable, and a fluid material, between said inner wall and said outer wall, said fluid material having a mechanical property that allows it to transmit applied force waves; and

actuating said fluid material at a frequency that causes constructive wave interaction within the fluid material and creates an induced wave on said inner lumen of a type that can drive a fluid flow through the inner lumen substantially without moving an outer wall of said outer lumen.

16. A method as in claim 15, further comprising another fluidic section, connected to said inner lumen, where said another section has a different fluidic characteristic than said inner lumen.

17. A method as in claim 15, further comprising controlling said actuating to produce an lower amplitude actuation of said material at a frequency that produces a higher amplitude actuating of said inner lumen.

18. A method as in claim 15, wherein said actuating is carried out from a location between said inner lumen and said outer lumen.

19. A method as in claim 15 wherein said fluid material is a hydrogel.

20. A method as in claim 17, wherein said actuation controls the lower amplitude waves to a frequency that causes constructive interference of waves within the fluid material, to create a higher amplitude wave on said inner lumen.

21. A method as in claim 20, wherein said higher amplitude wave is used to form a surface wave on said inner lumen.

22. A method as in claim 17, wherein said actuation controls the low amplitude waves to a frequency that causes a resonant effect, to create a higher amplitude wave on said inner lumen.

23. A method as in claim 15, wherein said fluid material has the viscosity of a gel.

24. A method, comprising:

inserting an inner tube and an outer tube that surrounds the inner tube, in a collapsed state into a body cavity;

using a stent to expand the outer tube;

inserting a gel like material between the outer tube and the inner tube; and

actuating the gel like material to cause excitation of the material and to allow a pumping effect in the inner tube.

25. A method as in claim 24, wherein said outer tube is extended to lay flush against the body cavity.

26. A method as in claim 24, wherein said actuating comprises controlling said actuating to produce an low amplitude actuation of said gel like material at a frequency that produces a higher amplitude actuating of said inner tube.

27. A method as in claim 24, wherein said actuating comprises not moving said outer tube.

28. A pump device, comprising:

an outer lumen, formed of a substantially unbending material; and

a pumping part, within said outer lumen, which pumps without dynamically exciting said outer lumen.

29. A pump as in claim 28, further comprising an inner lumen, within said outer lumen, said inner lumen formed of a material that is elastically deformable.

30. A pump as in claim 29, further comprising a material, between said inner wall and said outer wall, said material having a mechanical property that allows it to transmit an applied force.

31. A pump as in claim 30, further comprising an actuator, that actuates said material at a lower amplitude, that causes constructive wave interaction within the material, to cause an actuation of said inner lumen at a higher amplitude.

32. A method of pumping comprising:

exciting a fluid medium that is located between an outer lumen and an inner lumen; and

adjusting the excitation, so that waves are formed that can constructively interfere, and that allow a relatively small actuation wave to add and become a larger amplitude wave that is induced on the inner lumen.

33. A method as in claim 32, wherein said excitation is carried out substantially without dynamically exciting said outer lumen.

34. A method as in claim 32, wherein said fluid medium is a gel.

35. A method as in claim 33, further comprising using said outer lumen in a body cavity, and operating substantially without applying force to said body cavity.