Microfabricated therapeutic actuator mechanisms

• US 5,645,564 A
• Filed: 05/22/1995
• Issued: 07/08/1997
• Est. Priority Date: 05/22/1995
• Status: Expired due to Term

• Current Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Lee, Abraham P., Krulevitch, Peter A., Ciarlo, Dino R., Northrup, Milton A.
• Primary Examiner(s): Buiz, Michael Powell
• Assistant Examiner(s): LEONARDO, MARK
• Application Number:
  US08/446,146
• Time in Patent Office: 778 Days
• Field of Search: 606/205, 606/206, 606/207, 606/151, 606/211, 606/210, 128/751, 294/99.2
• US Class Current: 606/205
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/29 Forceps for use in minimally invasive surgery
• CPC Class Codes: A61B 2017/00292 mounted on or guided by flexible, e.g. catheter-like, means
• CPC Class Codes: A61B 2017/00345 Micromachines, nanomachines, microsystems
• CPC Class Codes: A61B 2017/00398 using powered actuators, e.g. stepper motors, solenoids
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61B 2017/12068 detachable by heat
• CPC Class Codes: A61B 2017/12077 Joint changing shape upon application of heat, e.g. bi-metal or reversible thermal memory
• CPC Class Codes: A61B 2017/12081 detachable by inflation
• CPC Class Codes: A61B 2017/2926 Details of heads or jaws
• CPC Class Codes: B25J 15/0206 comprising articulated grippers
• CPC Class Codes: B25J 7/00 Micromanipulators specimen supports for investigating or analysing materials G01N23/2204; associated with microscopes G02B21/32; means for supporting or positioning the objects or the material in discharge tubes H01J37/20
• CPC Class Codes: B81C 99/002 Apparatus for assembling MEMS, e.g. micromanipulators micromanipulators per se B25J7/00

Abstract

Electromechanical microstructures (microgrippers), either integrated circuit (IC) silicon-based or precision machined, to extend and improve the application of catheter-based interventional therapies for the repair of aneurysms in the brain or other interventional clinical therapies. These micromechanisms can be specifically applied to release platinum coils or other materials into bulging portions of the blood vessels also known as aneurysms. The "micro" size of the release mechanism is necessary since the brain vessels are the smallest in the body. Through a catheter more than one meter long, the micromechanism located at one end of the catheter can be manipulated from the other end thereof. The microgripper (micromechanism) of the invention will also find applications in non-medical areas where a remotely actuated microgripper or similar actuator would be useful or where micro-assembling is needed.

Claims

1. A microgripper, comprising:

a pair of flexible members constructed to have a cross-section capable of operating in an area having a diameter as small as 250 μ

m,

at least one of said flexible members being adapted to grip an associated object, and

means in contact with said member for retaining said member in gripping contact with an associated object, and for releasing said member from gripping contact with an associated object.

2. The microgripper of claim 1, wherein said pair of flexible members comprises a pair of coils, one of said pair of coils being adapted to grip an associated object, another of said pair of coils being adapted to force an associated object from said one of said pair of coils.

3. The microgripper of claim 2, wherein one coil of said pair of coils is larger in diameter than another coil of said pair of coils.

4. The microgripper of claim 1, wherein said flexible members comprises a pair of flexible gripping arms, said gripping arms having flexible gripper members at one end and are secured together at an opposite end.

5. The microgripper of claim 4, wherein said means includes an expandable device.

6. The microgripper of claim 4, wherein said means includes shaped-memory alloy films.

7. The microgripper of claim 4, wherein said means includes a compressive thin film.

8. The microgripper of claim 7, wherein said means additionally includes a shape-memory alloy wire.

9. The microgripper of claim 4, wherein each of said gripping arms is provided with means which allows an outer portion thereof to flex with respect to each other.

10. The microgripper of claim 4, wherein said gripping arms define a hollow channel therebetween.

11. The microgripper of claim 4, wherein each of said gripping arms include a pusher pad located in spaced relation to said gripper members.

12. The microgripper of claim 4, wherein said pair of gripping arms are constructed of silicon.

13. The microgripper of claim 1, additionally including means containing a fluid located between said pair of flexible members, whereby movement of said pair of members forces fluid from said means.

14. The microgripper of claim 1, additionally including heating means for causing movement of said pair of flexible members.

15. The microgripper of claim 14, additionally including shape-memory film on each of said pair of members, said heating means causing movement of said shape-memory film thereby causing movement of said pair of members.

16. The microgripper of claim 1, wherein said pair of flexible members are bonded together by Au--Si eutectic bonding.

17. The microgripper of claim 16, wherein the eutectic bonding of said pair of members is carried out by depositing an adhesive layer on at least one of the Si members, depositing an Au layer of the adhesive layer, annealing to the eutectic point of the Au layer, and pressurizing the Si members together for a time period, whereby a highly uniform and solid bond is formed.

18. A micromechanism adapted to be attached to a forward end of a catheter for use as a biopsy sampler or for use in interventional therapies, comprising:

a pair of bendable members connected at one end thereof and adapted to move at the other end thereof,

said pair of bendable members being constructed to have a cross-section capable of operating in an area having a diameter as small as about 250 μ

m,

each of said pair of bendable members including at least one gripper located at said other end thereof, and

means in contact with at least one of said pair of bendable members for causing movement of said other end thereof.

19. The micromechanism of claim 18, wherein each of said pair of bendable members additionally includes a pusher pad located in spaced relationship to said gripper.

20. The micromechanism of claim 18, wherein each of said pair of bendable members include a cantilever section.

21. The micromechanism of claim 20, wherein said means for causing movement of said other end of said pair of members comprises an expandable device.

22. The micromechanism of claim 18, wherein said means for causing movement of said other end of said pair of bendable members includes a quantity of a shape-memory alloy.

23. The micromechanism of claim 22, wherein said quantity of a shape-memory alloy is in the form of a wire, and wherein said pair of members include means into which said wire is removably inserted.

24. The micromechanism of claim 22, wherein said quantity of a shape-memory alloy is in the form of a film.

25. The micromechanism of claim 24, wherein said film extends along a surface of each of said pair of members.

26. The micromechanism of claim 25, wherein said film is located on an outer surface of each of said pair of members.

27. The micromechanism of claim 26, wherein said pair of members are constructed to form a hollow channel through said connected ends.

28. The micromechanism of claim 25, wherein said film is located on an inner surface of each of said pair of members.

29. The micromechanism of claim 28, wherein each of said pair of members includes a reduced cross-section portion located adjacent said film.

30. The micromechanism of claim 23, wherein each of said pair of members include a section containing a compressive film.