Apparatus and method for forming three-dimensional objects using a tilting solidification substrate

• US 10,300,663 B2
• Filed: 05/31/2018
• Issued: 05/28/2019
• Est. Priority Date: 02/20/2014
• Status: Active Grant

• Current Assignee: Gulf Filtration Systems Inc. (Desktop Metal, Inc.)
• Original Assignee: Gulf Filtration Systems Inc. (Desktop Metal, Inc.)
• Inventors: El-Siblani, Ali, Shkolnik, Alexandr
• Primary Examiner(s): Hindenlang, Alison L
• Assistant Examiner(s): Hohenbrink, Jr., Lawrence D.
• Application Number:
  US15/994,444
• Publication Number:
  US 20180272610A1
• Time in Patent Office: 362 Days
• CPC Class Codes: B29C 64/106 using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material
• CPC Class Codes: B29C 64/124 using layers of liquid which are selectively solidified
• CPC Class Codes: B29C 64/153 using layers of powder being selectively joined, e.g. by selective laser sintering or melting
• CPC Class Codes: B29C 64/245 Platforms or substrates support structures intended to be sacrificed after manufacture B29C64/40
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B29K 2827/12 containing fluorine
• CPC Class Codes: B29K 2883/005 LSR, i.e. liquid silicone rubbers, or derivatives thereof
• CPC Class Codes: B29K 2995/0026 Transparent
• CPC Class Codes: B29K 2995/0029 Translucent
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing

Abstract

An apparatus and method for making a three-dimensional object from a solidifiable material using a linear solidification device is shown and described. The apparatus includes a solidification substrate assembly that is tiltable about a tilting axis to peel a solidification substrate from a recently formed object surface and to level the solidification substrate assembly and squeeze out accumulated solidifiable material between the solidification substrate and the recently formed object surface. Intelligent peeling and leveling may also be provided by providing a tilting parameter database that is used to adjust tilting parameters based on object geometry and/or solidifiable material properties.

Claims

1. A method of making a three-dimensional object from a solidifiable material having a viscosity, comprising:

determining if the viscosity exceeds a selected viscosity threshold and carrying out the following steps if the viscosity exceeds the selected viscosity threshold;

solidifying a first layer of the solidifiable material in a first pattern corresponding to a first portion of the three-dimensional object to form a first solidified exposed object surface in contact with a solidification substrate assembly, wherein the first layer of the solidifiable material is located between a build platform and the solidification substrate assembly along a build axis, and the solidification substrate assembly comprises one selected from a film assembly and a solidification substrate laminate;

first tilting the solidification substrate assembly about a tilting axis in a direction away from the build platform;

moving the build platform away from the solidification substrate assembly within a volume of the solidifiable material to provide a second layer of solidifiable material between the solidified exposed object surface and the solidification substrate assembly;

second tilting the solidification substrate assembly about the tilting axis in a direction toward the build platform; and

solidifying the second layer of the solidifiable material in a second pattern corresponding to a second portion of the three-dimensional object.

2. The method of claim 1, wherein if the viscosity does not exceed the selected viscosity threshold, the method comprises:

solidifying the first layer of the solidifiable material in the first pattern corresponding to the first portion of the three-dimensional object to form the first solidified exposed object surface in contact with a solidification substrate, wherein the first layer of the solidifiable material is located between the build platform and the solidification substrate along the build axis;

moving the build platform away from the solidification substrate within the volume of the solidifiable material to provide the second layer of solidifiable material between the solidified exposed object surface and the solidification substrate; and

solidifying the second layer of the solidifiable material in the second pattern corresponding to the second portion of the three-dimensional object, wherein during the method the solidification substrate is not tilted about the tilting axis.

3. The method of claim 1, wherein after the completion of the step of moving the build platform away from the solidification substrate within a volume of the solidifiable material to provide a second layer between the solidified exposed object surface and the solidification substrate, the step of solidifying the second layer of the solidifiable material in a second pattern is carried out after the expiration of a leveling wait time, and the leveling wait time is no more than about 20 seconds.

4. The method of claim 2, wherein after the completion of the step of moving the build platform away from the solidification substrate within the volume of the solidifiable material to provide the second layer between the solidified exposed object surface and the solidification substrate, the step of solidifying the second layer of the solidifiable material in the second pattern is carried out after the expiration of a squeezing wait time, and the squeezing wait time is at least about 20 seconds.

5. The method of claim 1, further comprising:

applying a first level locking force to the solidification substrate assembly during the steps of solidifying the first layer of the solidifiable material and solidifying the first layer of the solidifiable material.

6. The method of claim 5, further comprising:

applying a second level locking force to the solidification substrate assembly during the step of moving the build platform away from the solidification substrate.

7. The method of claim 6, wherein first level locking force is greater than the second level locking force.

8. The method of claim 1, wherein the step of moving the build platform away from the solidification substrate within a volume of the solidifiable material to provide a second layer of solidifiable material between the solidified exposed object surface and the solidification substrate comprises first moving the build platform away from the solidification substrate by a distance greater than a desired layer thickness and second moving the build platform toward the solidification substrate by the difference between the distance and the desired layer thickness.

9. The method of claim 8, wherein the three-dimensional object comprises a plurality of layers, and step of first moving the build platform away from the solidification substrate by a distance greater than the desired layer thickness is carried out during the formation of no more than the first 30 layers of the three-dimensional object.

10. The method of claim 8, wherein the distance greater than the desired layer thickness is at least about two times the desired layer thickness.

11. The method of claim 10, wherein the distance greater than the desired layer thickness is not more than about 400 times the desired layer thickness.

12. The method of claim 1, wherein the solidification substrate assembly includes a pattern generator, and the step of solidifying a first layer of the solidifiable material comprises supplying solidification energy from the pattern generator to the first layer of the solidifiable material.

13. The method of claim 1, wherein the solidification substrate assembly comprises the solidification substrate laminate, and the solidification substrate laminate comprises a rigid or semi-rigid solidification substrate that is transparent and/or translucent.

14. The method of claim 1, wherein the solidification substrates assembly comprises the solidification substrate laminate, and the solidification substrate laminate comprises a film.

15. The method of claim 1, wherein the solidification substrate assembly comprises the solidification substrate laminate, the solidification substrate laminate comprises a resilient layer.

16. The method of claim 15, wherein the resilient layer comprises a silicone elastomer.

17. The method of claim 1, wherein the solidification substrate assembly comprises the solidification substrate laminate, and the solidification substrate laminate comprises a polymer film formed from ethylenically unsaturated, halogenated monomers.

18. The method of claim 17, wherein the polymer film is a fluoropolymer film.

19. The method of claim 1, wherein solidification substrate assembly comprises the solidification substrate laminate, the solidification substrate laminate comprises a resilient layer and a polymer film formed from ethylenically unsaturated halogenated monomers bonded to the resilient layer.

20. The method of claim 1, wherein the selected viscosity threshold is 1500 cP at 25°

C.