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EP-3851240-B1 - LASER CUTTING SYSTEM AND METHOD OF LASER CUTTING

EP3851240B1EP 3851240 B1EP3851240 B1EP 3851240B1EP-3851240-B1

Inventors

  • CULP, JAMES

Dates

Publication Date
20260513
Application Date
20120918

Claims (10)

  1. A laser cutting system, comprising: a fixture (104) comprising a platform (108) configured to hold a mold (206) in the shape of a set of teeth of a jaw, wherein the mold is configured to form a part comprising a dental appliance (332, 532) formed over the mold (206) from a sheet of material (208); a laser generating component (102) and one or more optical components (122), wherein the laser generating component (102) is configured to cut the sheet of material on the mold along a cut path (434) while the fixture is moved relative to the laser generating component, to trim excess material from the dental appliance (332, 532); a control component (110) comprising one or more control mechanisms configured to control the position of the fixture and to move the fixture relative to the laser generating component, wherein the control component (110) is configured to adjust the laser energy applied based on a material thickness of the sheet of material at multiple points along the cut path.
  2. The system of claim 1, wherein the control component (110) is configured to adjust the laser energy applied by the laser generating component (102).
  3. The system of claim 1, wherein the control component (110) is configured to position the fixture (104) in at least three axes of movement.
  4. The system of claim 1, wherein the control component (110) is configured to move the fixture (104) in at least five axes of motion with respect to the laser generating component (102).
  5. The system of claim 1, further comprising a sensor configured to detect a thickness of the sheet of material (208).
  6. The system of claim 1, wherein the control component (110) is configured to adjust the speed of movement of the fixture (104).
  7. The system of claim 1, wherein the control component (110) is configured to adjust the one or more optical components (122) to adjust the laser.
  8. The system of claim 1, wherein the control component (110) is configured to adjust the laser generating component (102) such that a ratio of laser energy applied to the part and the part material thickness is maintained within a predetermined acceptable range at each point along a cut path to cut through the part and into an outer surface of a support for the part but not through the mold.
  9. The system of claim 1, wherein the control component (110) is configured to adjust the speed of the fixture (104) such that the laser energy vaporizes all material of the part at each point along the cut path on the part while obtaining at least one of the desired edge condition or edge characteristic.
  10. The system of claim 1, wherein the fixture comprises a rotating mechanism (126) that rotates the part in a clockwise and/or counterclockwise direction when viewed from above the platform (108).

Description

Technical Field The present disclosure relates to systems for laser cutting. Background Laser cutting systems have been devised and are utilized in many industries. For example, in the auto industry a laser cutting system is used to cut the edging on a bumper that is formed using a mold, stamping press, or other forming tool. Once formed, the bumper is removed from the mold, press, etc., but often includes some extra material around the edges from the mold formation process. A laser cutting system can be used to remove this extra material from the bumper. Accordingly, the laser cuts the material off and the edge of the part is polished through hand polishing, or other such manners, to remove any sharp portions and generally smooth the edge. In some other implementations, an item is formed on a mold and a laser is used to cut the item off of the mold. Alternatively, an item is formed on a mold by stamping or another forming process and the item is positioned using a support of some kind. If the item has been molded, the mold may be used as the support. However, cutting into the support material can be detrimental to the process. For instance, the support material, when cut with the laser, may mix with the material used to form the item. This can cause unintended material physical characteristics or discoloration, which may not be desirable. The cutting process itself can also change the characteristics of the material near the cut path. Unlike other cutting techniques, laser cutting generates enough heat to cut the material and, as such, the material's interaction with the heat can change its characteristics, for example, making it more brittle which can be undesirable in some applications. This can be particularly true where the cut is to be made at relatively high speed and therefore a high energy laser beam is used to cut through the material quickly. Additionally, the thickness of the material being cut can change in some implementations and as such, the effectiveness of the cutting technique can be reduced. For example, if a portion of the material being cut is thicker than a portion used to calibrate the laser for most effective cutting, the laser may not cut all the way through the material or the material may not be vaporized as effectively. If the material is thinner, the characteristics of the edge of the cut material may be changed in an unintended manner. The laser may also cut through the item being cut and into the support material which may be undesirable in some applications as discussed above. US 2008/141534 A1 describes a robotic system for forming features in orthodontic aligners including a control system, a platen for three-dimensional positioning of the aligner, a heating station for selectively heating a small region of the aligner, and a thermoforming station for manipulating the heated region to form a desired feature in the aligner. Optionally, a laser cutting and trimming station can also be included to trim excess material from the aligner or to cut features into the aligner. Brief Description of the Drawings Figure 1 illustrates a system that can be used in accordance with one or more embodiments of the present disclosure.Figure 2 illustrates a piece of part material being applied over a mold according to one or more embodiments of the present disclosure.Figure 3 illustrates a part being created by forming the piece of part material over at least a portion of the surface of the mold according to one or more embodiments of the present disclosure.Figure 4 illustrates a cut path on a part according to one or more embodiments of the present disclosure.Figure 5 illustrates the cut part being removed from the mold according to one or more embodiments of the present disclosure.Figure 6 illustrates one example of five axis movement types that can be used according to one or more embodiments of the present disclosure.Figure 7 illustrates a method according to one or more embodiments of the present disclosure. Detailed Description The invention is defined by the appended claims. Laser cutting systems and methods are described herein. For example, one or more systems include a laser generating component, an optical component, a fixture for holding a support with a part positioned on the support, and a control mechanism for adjusting at least one of the laser generating component, the optical component, and the fixture such that a ratio of a laser energy applied to the part and a part material thickness is maintained within a predetermined acceptable range at each point along a cut path to cut through the part while maintaining the integrity of the support. Other systems and methods are disclosed herein. Embodiments of the present disclosure can cut through a material for forming a part without cutting into a support material adjacent to the part material. In some embodiments, the laser beam can cut through the part material, but not substantially into the support material. In such instances