Laser-Transmitting Tooling

• US 20180015578A1
• Filed: 07/18/2017
• Published: 01/18/2018
• Est. Priority Date: 07/18/2016
• Status: Active Grant

• Current Assignee: Micro-LAM, Inc.
• Original Assignee: Micro-LAM, Inc.
• Inventors: Ravindra, Deepak VM, Kode, Sai Kumar
• Granted Patent: US 10,449,644 B2
• Time in Patent Office: Days
• CPC Class Codes: B23B 1/00 Methods for turning or working essentially requiring the use of turning-machines; Use of auxiliary equipment in connection with such methods
• CPC Class Codes: B23B 2226/31 Diamond
• CPC Class Codes: B23B 2260/092 Lasers
• CPC Class Codes: B23B 27/14 Cutting tools of which the bits or tips or cutting inserts are of special material
• CPC Class Codes: B23B 27/145 characterised by having a special shape
• CPC Class Codes: B23B 27/20 with diamond bits or cutting inserts
• CPC Class Codes: B23C 2226/31 Diamond
• CPC Class Codes: B23C 2260/56 Lasers
• CPC Class Codes: B23C 5/16 characterised by physical features other than shape
• CPC Class Codes: B23K 26/0093 combined with mechanical machining or metal-working covered by other subclasses than B23K combined welding or cutting procedures or apparatus B23K28/02
• CPC Class Codes: B23K 26/064 by means of optical elements, e.g. lenses, mirrors or prisms
• CPC Class Codes: B23K 26/0648 comprising lenses
• CPC Class Codes: B23P 25/006 Heating the workpiece by laser during machining

Abstract

A laser-transmitting machining tool is disclosed. The laser-transmitting machining tool has a plurality of faces including an entrance face, a rake face, a flank face connected to the rake face, a rake side face extending between the entrance face and the rake face, and a flank side face extending between the entrance face and the flank face. The connection of the rake face to the flank face defines a cutting edge. The rake face extends away from the rake side face to define a rake angle. The entrance face is configured to receive and refract a laser beam to the rake face, the flank face, and the cutting edge for causing the laser beam to refract into and heat the workpiece at a compression region extending proximate at least the rake face and a tensile region extending proximate the flank face. A system for machining a workpiece is disclosed. A method for machining a workpiece is also disclosed.

Claims

1. A laser-transmitting machining tool for machining a workpiece, the laser-transmitting machining tool comprising:

a body of material having an entrance face, a rake face, a flank face connected to the rake face, a rake side face extending between the entrance face and the rake face, and a flank side face extending between the entrance face and the flank face,

wherein the connection of the rake face to the flank face defines a cutting edge,

wherein the entrance face is configured to receive and refract a laser beam to the rake face, the flank face, and the cutting edge, causing the laser beam to refract into and heat the workpiece at a compression region extending proximate at least the rake face and a tensile region extending proximate the flank face, and

wherein the rake face extends away from the rake side face to define a rake angle and the flank face extends away from the flank side face to define a flank angle relative to the rake angle, the rake angle is sized to define one of the following rake angles including;

a highly negative rake angle causing the compression region of the workpiece to be a highest compression region and the tensile region of the workpiece to be a lowest tensile region;

a midrange negative rake angle causing the compression region of the workpiece to be a high compression region and the tensile region of the workpiece to be a low tensile region;

a low-range negative rake angle causing the compression region of the workpiece to be a medium compression region and the tensile region of the workpiece to be a medium tensile region;

a zero rake angle causing the compression region of the workpiece to be a low compression region and the tensile region of the workpiece to be a high tensile region; and

a positive rake angle causing the compression region of the workpiece to be a lowest compression region and the tensile region of the workpiece to be a highest tensile region.

2. The laser-transmitting machining tool of claim 1, wherein each of the highest compression region, the high compression region, the medium compression region, the low compression region and the lowest compression region also extends along the cutting edge.

3. The laser-transmitting machining tool of claim 1, wherein each of the highest tensile region, the high tensile region, the medium tensile region, the low tensile region and the lowest tensile region also extends along the cutting edge.

4. The laser-transmitting machining tool of claim 1, wherein the highly negative rake angle is less than each of the midrange negative rake angle, the low-range negative rake angle, the zero rake angle and the positive rake angle.

5. The laser-transmitting machining tool of claim 1, wherein the highly negative rake angle is greater than about 90°

and less than about 135°

, wherein the midrange rake angle is greater than about 136° and

less than about 165°

, wherein the low-range negative rake angle is greater than about 166° and

less than about 179°

.

6. The laser-transmitting machining tool of claim 1, wherein the zero rake angle is approximately 180°

.

7. The laser-transmitting machining tool of claim 1, wherein the positive rake angle is greater than about 181°

and less than about 210°

.

8. The laser-transmitting machining tool of claim 1, wherein the material is selected from the group consisting of:

a diamond, a sapphire, a carbide, cubic boron nitride (CBN), silicon, nitrides, steels, alloys, ceramics, alumina, crystals and glass composites.

9. The laser-transmitting machining tool of claim 1, wherein the material comprises diamond, wherein the rake angle is sized to define the highly negative rake angle, the midrange negative rake angle or low-range negative rake angle, wherein a relief angle defined by the entrance face relative to the laser beam is approximately 5°

.

10. The laser-transmitting machining tool of claim 1, wherein the material comprises sapphire, wherein the rake angle is sized to define the highly negative rake angle, the midrange negative rake angle or low-range negative rake angle, wherein a relief angle defined by the entrance face relative to the laser beam is approximately 7°

.

11. The laser-transmitting machining tool of claim 1, wherein the material comprises diamond, wherein the rake angle is sized to define zero rake angle, wherein a relief angle defined by the entrance face relative to the laser beam is approximately 7°

.

12. The laser-transmitting machining tool of claim 1, further comprising an anti-reflective coating disposed over the entrance face.

13. A system for machining a workpiece comprising:

a laser-transmitting machining tool including a body of material having a plurality of faces including a rake face that is connected to a flank face for defining a cutting edge of the laser-transmitting machining tool, wherein the rake face extends away from a side face of the plurality of faces to define a rake angle, wherein the rake angle is sized to define one of a plurality of rake angles including;

a highly negative rake angle causing the compression region of the workpiece to be a highest compression region and the tensile region of the workpiece to be a lowest tensile region;

a midrange negative rake angle causing the compression region of the workpiece to be a high compression region and the tensile region of the workpiece to be a low tensile region;

a low-range negative rake angle causing the compression region of the workpiece to be a medium compression region and the tensile region of the workpiece to be a medium tensile region;

a zero rake angle causing the compression region of the workpiece to be a low compression region and the tensile region of the workpiece to be a high tensile region; and

a positive rake angle causing the compression region of the workpiece to be a lowest compression region and the tensile region of the workpiece to be a highest tensile region,

wherein the plurality of faces define a laser beam entrance end of the laser-transmitting machining tool and a laser beam exit end of the laser-transmitting machining tool, wherein the laser beam exit end is defined by the rake face, the flank face and the cutting edge;

a housing having an upstream end and a downstream end, wherein the downstream end of the housing is optically-connected to the laser beam exit end of the laser-transmitting machining tool;

a laser generator optically-connected to the upstream end of the housing for optically-communicating a laser beam generated by the laser generator from the upstream end of the housing to the laser beam entrance end, through the body of material, and out of;

the cutting edge; and

one or both of the rake face and the flank face.

14. The system of claim 13, wherein the housing includes:

optics; and

an optics interface, wherein the optics includes at least a collimating lens and a series of focusing lens, wherein the collimating lens is optically-connected to the laser generator for collimating the laser beam prior to being received by the laser beam entrance end of the laser-transmitting machining tool, wherein the series of focusing lens are optically-connected to the collimating lens for focusing the laser beam prior to being received by the laser beam entrance end of the laser-transmitting machining tool, wherein the optics interface includes a focusing knob connected to the series of focusing lens that adjusts focal plane and a diameter of the laser beam for selectively biasing rays of the laser beam toward the rake face or the flank face, wherein the optics interface includes one or more beam positioning stages connected to the series of focusing lens that alters an angle of laser beam as the laser beam exits the collimating lens.

15. The system of claim 14 further including:

an X-axis micrometer adjustment knob connected to the optics;

a Y-axis micrometer adjustment knob connected to the optics; and

a Z-axis micrometer adjustment knob optics, wherein the X-, Y- and Z-axis micrometer adjustment knobs are connected to the optics for selectively biasing rays of the laser beam toward the rake face or the flank face.

16. The system of claim 14 further including:

an optic sub-housing contained within the housing, wherein the optic sub-housing is connected to the housing with a spatial adjusting device for adjusting the optics contained within the optical sub-housing in any of an X-direction, a Y-direction or a Z-direction of a three dimensional XYZ coordinate system for adjusting entry of the laser beam into the laser beam entrance end of the laser-transmitting machining tool.

17. The system of claim 13 further including:

a heat-activated or laser-activated cutting fluid, slurry or etchant contained within a supply or reservoir that is communicated out of a nozzle to the laser beam exit end of the laser-transmitting cutting tool; and

an actuator including one or more of a pump and valve that is fluidly connected to the supply or reservoir for asserting control over an amount of the heat-activated or laser-activated cutting fluid, slurry or etchant that is to be disposed upon the laser beam exit end of the laser-transmitting cutting tool.

18. The system of claim 13 further including:

a second laser generator optically-connected to the upstream end of the housing for optically-communicating a second laser beam generated by the second laser generator from the upstream end of the housing to the laser beam entrance end, through the body of material, and out of;

the cutting edge; and

one or both of the rake face and the flank face.

19. The system of claim 15 further including:

a visible beam imaging camera includes beam alignment software; and

a computer workstation connected to the visible beam imaging camera, wherein the visible beam imaging camera images a visible calibration light beam propagating through laser-transmitting machining tool and communicates an image of the visible calibration light beam propagating through the laser-transmitting machining tool to the beam alignment software, wherein, upon the beam alignment software determining that the visible calibration light beam passing through the laser-transmitting machining tool is not aligned, the beam alignment software provides instructions to the computer workstation for displaying on a display instructions or a suggested optimization value associated with adjustment or rotation of one or more of the X-, Y- and Z-axis micrometer adjustment knobs.

20. The system of claim 19 further including:

an energy meter or power meter connected to the computer workstation for measuring output power of the laser beam passing through the cutting edge of the laser-transmitting machining tool.

21. The system of claim 19 further including:

a beam profiler connected to the computer workstation for detecting an orientation angle or geometry of the laser-transmitting machining tool for aligning the laser beam passing through the laser-transmitting machining tool.

22. The system of claim 13 further including:

a precision tool height adjuster connected to the housing.

23. The system of claim 13 further including:

a smart swivel system connected to the housing.

24. The system of claim 13 further including:

an isolated rotary bearing system connected to the housing; and

a beam splitter disposed within and arranged near the downstream end of the housing for delivering the laser beam to multiple locations of the laser beam entrance face.

25. A method for machining a workpiece, the method comprising:

transmitting, from a laser generator, a laser beam;

receiving, at an upstream end of a housing that is optically-connected to the laser generator, the laser beam;

receiving, at a laser beam entrance face that defines a laser beam entrance end of a laser-transmitting machining tool that is optically-connected to a downstream end of a housing, the laser beam;

transmitting the laser beam through the a body of material of the laser-transmitting machining tool that extends between the laser beam entrance end of the laser-transmitting machining tool and a laser beam exit end of the laser-transmitting machining tool;

selectively directing the laser beam out of a cutting edge of the laser-transmitting machining tool and one or both of a rake face of the laser-transmitting machining tool and a flank face of the laser-transmitting machining tool, wherein the cutting edge, the rake face and the flank face defines the laser beam exit end of the laser-transmitting machining tool, wherein the rake face extends away from a side face of the laser-transmitting machining tool to define a rake angle, wherein the rake angle is sized to define one of a plurality of rake angles including;

a highly negative rake angle causing the compression region of the workpiece to be a highest compression region and the tensile region of the workpiece to be a lowest tensile region;

a midrange negative rake angle causing the compression region of the workpiece to be a high compression region and the tensile region of the workpiece to be a low tensile region;

a low-range negative rake angle causing the compression region of the workpiece to be a medium compression region and the tensile region of the workpiece to be a medium tensile region;

a zero rake angle causing the compression region of the workpiece to be a low compression region and the tensile region of the workpiece to be a high tensile region; and

a positive rake angle causing the compression region of the workpiece to be a lowest compression region and the tensile region of the workpiece to be a highest tensile region.

26. The method of claim 25, wherein the laser beam is defined by a diameter having a central ray extending along a central axis of the laser beam, a first circumferential array of rays arranged at a first radial distance away from the central axis of the laser beam and at least one second circumferential array of rays arranged at a second radial distance away from the central axis of the laser beam whereby the second radial distance is greater than the first radial distance, wherein selectively directing the laser beam includes:

directing the central ray of the laser beam out of the cutting edge of the laser-transmitting machining tool; and

biasing one or both of the first circumferential array of rays of the laser beam and the second circumferential array of rays of the laser beam toward one of the rake face and the flank face.

27. The method of claim 26, wherein biasing one or both of the first circumferential array of rays of the laser beam and the second circumferential array of rays of the laser beam toward one of the rake face and the flank face includes:

adjusting a focusing knob connected to a series of focusing lens disposed within the housing that adjusts focal plane and the diameter of the laser beam.

28. The method of claim 26, wherein biasing one or both of the first circumferential array of rays of the laser beam and the second circumferential array of rays of the laser beam toward one of the rake face and the flank face includes:

adjusting one or more beam positioning stages connected to a series of focusing lens disposed within the housing for altering an angle of laser beam as the laser beam exits a collimating lens disposed within the housing.

29. The method of claim 26, wherein biasing one or both of the first circumferential array of rays of the laser beam and the second circumferential array of rays of the laser beam toward one of the rake face and the flank face includes:

adjusting one or more of an X-axis micrometer adjustment knob, a Y-axis micrometer adjustment knob connected to the optics and a Z-axis micrometer adjustment knob connected to a series of focusing lens disposed within the housing.