Ultrasonic handpiece

• US 7,651,490 B2
• Filed: 08/12/2004
• Issued: 01/26/2010
• Est. Priority Date: 08/12/2004
• Status: Active Grant

• Current Assignee: Alcon Incorporated
• Original Assignee: Alcon Incorporated
• Inventors: Chon, James Y., Boukhny, Mikhail
• Primary Examiner(s): Ho; (Jackie) Tan-Uyen T
• Assistant Examiner(s): Dornbusch; Dianne
• Application Number:
  US10/916,675
• Publication Number:
  US 20060036180A1
• Time in Patent Office: 1,993 Days
• Field of Search: 606/128, 606/159, 606/169, 606/170, 606/171, 606/180, 600/437, 600/439, 600/471, 604/22
• US Class Current: 606/1
• CPC Class Codes: A61B 2017/32007 with suction or vacuum means
• CPC Class Codes: A61B 2017/320089 node location
• CPC Class Codes: A61F 9/00745 using mechanical vibrations, e.g. ultrasonic
• CPC Class Codes: A61F 9/00763 with rotating or reciprocating cutting elements, e.g. concentric cutting needles atherectomy cutting instruments A61B17/3207; endoscopic cutting instruments A61B17/320016

Abstract

A handpiece having a single set of piezoelectric elements polarized to produce longitudinal motion when excited at the relevant resonant frequency. The piezoelectric crystals are connected to an ultrasonic horn to which a cutting tip is attached. The horn and/or the cutting tip contains a plurality of diagonal slits or grooves. The slits or grooves produce optimized torsional movement in the cutting tip when the piezoelectric crystals are excited at a second resonant frequency. Preferably, the two drive frequencies are not coincident, but provided in non-overlapping pulses.

Claims

1. An ultrasonic handpiece, comprising:

a) a handpiece shell;

b) an ultrasonic horn held within the shell, the horn containing a plurality of circumferential, diagonal slits sized and spaced so as to produce torsional movement in the horn in response to a drive signal having a first frequency and longitudinal movement in the horn in response to a drive signal having a second frequency; and

c) a plurality of piezoelectric elements;

wherein the piezoelectric elements and the horn are held within the shell so that a torsional nodal point and a proximal longitudinal nodal point are coincident at a plug that seals the shell on an end of the handpiece opposite a cutting tip.

2. The apparatus of claim 1 wherein the first drive signal and the second drive signal are alternated and do not overlap.

3. An ultrasonic handpiece comprising:

a handpiece shell;

an ultrasonic horn at least partially located in the shell, the horn having a plurality of slits sized and spaced so as to produce torsional movement in the horn in response to a drive signal having a first frequency and longitudinal movement in the horn in response to a drive signal having a second frequency;

a piezoelectric element connected to the horn; and

a plug that seals the shell on an end of the handpiece opposite a cutting tip;

wherein a torsional nodal point and a longitudinal nodal point are coincident at the plug.

4. The handpiece of claim 3 wherein the plurality of slits are spiral.

5. The handpiece of claim 3 wherein the plurality of slits are helical.

6. The handpiece of claim 3 further comprising:

an aspiration shaft extending through the horn.

7. The handpiece of claim 6 further comprising:

the cutting tip coupled o the aspiration shaft.

8. The handpiece of claim 3 wherein the horn has an outside diameter, and the width of the plurality of slits is between about 2% and 65% of the outside diameter of the horn.

9. The handpiece of claim 8 wherein the depth of the plurality of slits is between about 4% and 45% of the outside diameter of the horn.

10. The handpiece of claim 3 wherein the horn has a larger diameter, and the plurality of slits are between about 8% and 75% of the length of the larger diameter of the horn.

11. The handpiece of claim 10 wherein the pitch of the plurality of slits is between about 125% and 500% of the larger diameter of the horn.

12. The handpiece of claim 3 further comprising:

a drive circuit for driving the handpiece.

13. The handpiece of claim 3 wherein the first frequency is about 32 kHz.

14. The handpiece of claim 3 wherein the second frequency is about 44 kHz.

15. An ultrasonic handpiece comprising:

a handpiece shell;

be a plug that seals the shell on an end of the handpiece opposite a cutting tip;

an ultrasonic horn at least partially located in the shell and coupled to the shell at the plug, the horn having a plurality of slits sized and spaced so as to produce torsional movement in the horn in response to a drive signal having a first frequency and longitudinal movement in the horn in response to a drive signal having a second frequency; and

a piezoelectric element connected to the horn;

wherein a torsional nodal point and a longitudinal nodal point are coincident at the plug.

16. The handpiece of claim 15 wherein the horn is sealed to the shell at the plug location.

17. A phacoemulsification handpiece comprising:

a handpiece shell;

a horn at least partially located in the shell and sealed to the shell at a plug, the horn having a plurality of slits sized and spaced so as to produce torsional movement in the horn in response to a drive signal having a first frequency and longitudinal movement in the horn in response to a drive signal having a second frequency;

a tip coupled to the horn, the tip suitable for insertion into an eye, the tip configured to remove a lens from the eye when the tip is vibrated; and

a piezoelectric element coupled to the horn;

wherein a torsional nodal point and a longitudinal nodal point are coincident at the plug that seals the shell on an end of the handpiece opposite the tip.

18. The handpiece of claim 17 further comprising:

an aspiration shaft extending through the horn.

19. The handpiece of claim 17 further comprising:

a drive circuit for driving the piezoelectric element.

20. A phacoemulsification handpiece comprising:

a handpiece shell configured to be held in the hand;

a horn at least partially located in the shell, the horn having a plurality of slits sized and spaced so as to produce torsional movement in the horn in response to a drive signal having a first frequency and longitudinal movement in the horn in response to a drive signal having a second frequency;

a hollow tip coupled to the horn, the hollow tip suitable for insertion into an eye, the hollow tip configured to remove a lens from the eye when the hollow tip is vibrated;

an aspiration shaft extending through the horn;

a piezoelectric element coupled to the horn;

a drive circuit for driving the piezoelectric element; and

a plug that seals the shell on an end of the handpiece opposite the hollow tip;

wherein a torsional nodal point and a longitudinal nodal point are coincident at the plug.