LASER CUTTING PROCESS FOR FORMING STENTS

• US 20100193483A1
• Filed: 02/03/2010
• Published: 08/05/2010
• Est. Priority Date: 02/03/2009
• Status: Active Grant

• Current Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories)
• Inventors: Yribarren, Travis, Ku, Yu-Chun, Von Oepen, Randolf, Chen, Li
• Granted Patent: US 8,872,062 B2
• Time in Patent Office: Days
• US Class Current: 219/121.72
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91566 connected trough to trough
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: B23K 26/0626 Energy control of the laser beam B23K26/0622 takes precedence
• CPC Class Codes: B23K 26/0823 Devices involving rotation of the workpiece
• CPC Class Codes: B23K 26/36 Removing material B23K26/55, B23K26/57 take precedence
• CPC Class Codes: B23K 26/361 for deburring or mechanical trimming B23K26/351 takes precedence
• CPC Class Codes: B23K 26/38 by boring or cutting

Abstract

Systems and methods for improving the cutting efficiency and cut profile of stent strut is provided. A means for altering the energy distribution of a laser beam is provided, along with various ways of controlling a laser to provide for improved strut configurations are provided. A method for improved cutting speeds using a combination of laser sources is also provided.

Claims

1. A laser cutting system for cutting a stent pattern into a stent, comprising:

a laser for producing a laser beam;

a laser-shaping module capable of altering the intensity profile of the laser beam;

a collimating lens; and

a focusing lens.

2. A method for shaping a laser beam for cutting a stent pattern into a stent, comprising:

providing a laser beam having a first intensity distribution; and

re-mapping the first intensity distribution of the laser beam to a second intensity distribution.

3. The method of claim 2, wherein the first intensity distribution is a Gaussian intensity distribution.

4. The method of claim 2, wherein the second intensity distribution is a top hat intensity distribution.

5. The method of claim 2, wherein the second intensity distribution is a non-Gaussian intensity distribution.

6. A method for cutting a stent pattern into a tube, comprising:

remapping the intensity distribution of a laser beam to a non-Gaussian intensity distribution; and

applying the non-Gaussian intensity beam to a tube to remove at least a portion of a wall thickness of the tube.

7. The method of claim 6, wherein applying the beam to the tube includes exposing the tube to multiple passes of the laser beam.

8. The method of claim 6, wherein remapping includes providing a non-Gaussian intensity distribution to the laser beam, the non-Gaussian intensity distribution having at least one characteristic resulting in removing material from the wall of the tube in a selected configuration.

9. The method of claim 8, wherein the selected configuration includes forming indentations on a surface of the tube.

10. A system for cutting a stent pattern into a tube, comprising:

a tube mounted in a fixture, the tube having a central axis;

a first laser beam for cutting a portion of a pattern into the tube, the first laser and tube arranged relative to one another such that the laser beam is directed to a surface of the tube on an axis that is offset from the central axis of the tube;

a second laser beam for cutting a second portion of the pattern in the tube, the second laser beam and tube arranged relative to one another such that the laser beam is directed to the surface of the tube on an axis that is offset from the central axis of the tube and the axis of the first laser beam.

11. A system for cutting stent patterns into a tube, comprising:

a tube mounted in a fixture, the tube having a central axis;

a laser for providing a laser beam for cutting a portion of a pattern into the tube, the laser beam and tube moveable with respect to one another such that the laser beam is oriented in a first position relative to the tube and the beam directed to a first surface of the tube on an axis that is offset from the central axis.

12. The system of claim 11, wherein the laser beam or tube are moved to a second position such that the laser beam is directed to a second surface of the tube, the axis of the laser beam being offset to the central axis of the tube by an offset different from the offset used to cut the first surface of the tube.

13. The system of claim 12, wherein a rectangular strut is produced.

14. A method of cutting a stent pattern into a tube, comprising:

mounting a tube in a fixture;

cutting a pattern into the tube to a depth less than a wall thickness of the tube using a long pulse laser, the laser and fixture controlled by a computer to provide for relative motion between the long pulse laser and the tube; and

cutting the pattern into the tube to a depth greater than the wall thickness of the tube using a short pulse laser, the short pulse laser and fixture controlled by the computer to provide for relative motion between the short pulse laser and the tube.

15. The method of claim 14, wherein the tube is moved to a different location before the pattern is cut by the short pulse laser.

16. The method of claim 14, wherein the long pulse laser and the short pulse laser and fixture are mounted on a common base.

17. A method for cutting a stent pattern into a tube, comprising:

mounting a tube is a fixture;

configuring a laser to operate in a first mode;

cutting a pattern into the tube to a depth less than a wall thickness of the tube using the laser operating in the first mode, the laser and fixture controlled by a computer to provide for relative motion between the laser and the tube;

configuring the laser to operate in a second mode; and

cutting the pattern into the tube to a depth greater than the wall thickness of the tube using the laser operating in the second mode, the laser and fixture controlled by the computer to provide for relative motion between the laser and the tube.

18. The method of claim 17, wherein the first mode is a long pulse mode.

19. The method of claim 17, wherein the second mode is different from the first mode.

20. The method of claim 19, wherein the second mode is a short pulse mode.