Methods and Apparatus for 3D Fabrication

• US 20130171431A1
• Filed: 08/29/2012
• Published: 07/04/2013
• Est. Priority Date: 08/29/2011
• Status: Active Grant

• Current Assignee: Impossible Objects, Inc
• Original Assignee: Impossible Objects, Inc
• Inventors: Swartz, Robert, Fallon, Joseph, Crist, Buckley
• Granted Patent: US 9,827,754 B2
• Time in Patent Office: Days
• US Class Current: 428/196
• CPC Class Codes: B29C 64/141 using only solid materials
• CPC Class Codes: B29C 64/147 using sheet material, e.g. laminated object manufacturing [LOM] or laminating sheet material precut to local cross sections of the 3D object
• 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 64/165 using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber
• CPC Class Codes: B29K 2995/0021 Multi-coloured
• CPC Class Codes: B32B 1/00 Layered products having a non-planar shape
• CPC Class Codes: B32B 2250/20 All layers being fibrous or filamentary
• CPC Class Codes: B32B 2260/021 Fibrous or filamentary layer
• CPC Class Codes: B32B 2260/04 Impregnation, embedding, or binder material
• CPC Class Codes: B32B 2260/046 Synthetic resin
• CPC Class Codes: B32B 2262/02 Synthetic macromolecular fibres
• CPC Class Codes: B32B 2262/0276 Polyester fibres
• CPC Class Codes: B32B 2262/101 Glass fibres
• CPC Class Codes: B32B 2262/103 Metal fibres
• CPC Class Codes: B32B 2262/106 Carbon fibres, e.g. graphite fibres
• CPC Class Codes: B32B 2307/50 having particular mechanical properties
• CPC Class Codes: B32B 2307/718 Weight, e.g. weight per square meter
• CPC Class Codes: B32B 37/1284 Application of adhesive
• CPC Class Codes: B32B 5/02 characterised by structural features of a fibrous or filamentary layer layer formed of metallic wires B32B15/02; layer formed of natural mineral fibres B32B19/02; layer formed of wood fibres B32B21/02
• CPC Class Codes: B32B 5/022 Non-woven fabric
• CPC Class Codes: B32B 5/024 : Woven fabric
• CPC Class Codes: B32B 5/22 : characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed layer formed of natural mineral fibres or particles next to a foam layer B32B19/047, next to a layer made of particles B32B19/048, or next to a fibrous or filamentary layer B32B19/06; paper layer or cardboard layer next to a paper layer or cardboard layer B32B29/005, next to a foam layer B32B29/007, next to a fibrous or filamentary layer B32B29/02, or next to a particulate layer B32B29/04
• CPC Class Codes: B32B 5/26 : another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: B32B 7/14 : applied in spaced arrangements, e.g. in stripes
• 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: G03G 15/224 : Machines for forming tactile or three dimensional images by electrographic means, e.g. braille, 3d printing
• CPC Class Codes: Y10T 428/2481 : including layer of mechanically interengaged strands, strand-portions or strand-like strips
• CPC Class Codes: Y10T 428/24826 : Spot bonds connect components
• CPC Class Codes: Y10T 428/24843 : with heat sealable or heat releasable adhesive layer

Abstract

In an illustrative implementation of this invention, a 3D object comprises substrate layers infiltrated by a hardened material. The 3D object is fabricated by a method comprising the following steps: Position powder on all or part of a substrate layer. Repeat this step for the remaining substrate layers. Transform the powder into a substance that flows and subsequently hardens into the hardened material. The hardened material solidifies in a spatial pattern that infiltrates positive regions in the substrate layers and does not infiltrate negative regions in the substrate layers.

Claims

1. A method of fabricating a 3D object, which 3D object comprises a plurality of substrate layers that are infiltrated by and bound together by a hardened material, the method comprising the following steps, in combination:

(1a) positioning powder on all or part of at least one of the layers;

(1b) repeating step (1a) for remaining layers in the plurality of substrate layers; and

(1c) transforming at least some of the powder into a substance that flows and subsequently hardens into the hardened material, which hardened material is disposed in a spatial pattern that infiltrates at least one positive region in a set of the substrate layers and does not infiltrate at least one negative region in the set;

wherein the powder is transformed in step (1c) after being positioned in either step (1a) or step (1b), and wherein the substrate layers have at least one material property that is different than any material property of the hardened material.

2. The method of claim 1, wherein the positioning (1a) comprises selectively applying the powder to part but not all of a surface of the layer.

3. The method of claim 1, wherein the positioning (1a) is in accordance with a machine-readable digital model of a slice of the 3D object.

4. The method of claim 1, wherein the transforming (1c) comprises melting at least part of the powder.

5. The method of claim 1, wherein the powder comprises grains that each, respectively encapsulate a liquid, and wherein the transforming (1c) comprises rupturing, bursting or crushing at least some of the grains.

6. The method of claim 1, wherein the transforming (1c) comprises a chemical reaction.

7. A method of fabricating a 3D object, which 3D object comprises a plurality of layers and a hardened substance that binds the layers together, the method comprising the following steps, in combination:

(7a) selectively depositing powder on a positive region, but not on at least part of a negative region, of one of the layers;

(7b) repeating step (7a) for remaining layers in the plurality of layers;

(7c) transforming at least some of the powder into matter that flows and subsequently becomes the hardened substance, which hardened substance is disposed in a spatial pattern that infiltrates the layers; and

(7d) removing material from at least one negative region of at least one substrate layer;

wherein the powder is transformed in step (7c) after being deposited in either step (7a) or step (7b), and wherein the substrate layers have at least one material property that is different than any material property of the hardened substance.

8. The method of claim 7, wherein the selectively depositing (7a) powder on a positive region of the one of the layers comprises a first substep and a second substep, the first substep comprising selectively depositing liquid on the positive region, and the second substep comprising positioning the powder on or adjacent to the one of the layers to adhere the powder to the liquid.

9. The method of claim 8, further comprising a third substep, which third substep comprises removing powder that does not adhere to the liquid.

10. The method of claim 7, wherein the layers comprise PET or PLA and wherein an alkali, alone or together with one or more other substances, is used for the removing (7d).

11. Apparatus for fabricating a 3D object, which object comprises a plurality of layers and a hardened substance, the apparatus comprising, in combination:

an applicator, the applicator being configured for selectively depositing powder in at least some positive regions, but not in at least some negative regions, of at least some of the layers; and

a heating element, the heating element being configured for transforming the powder into matter that flows and then hardens into the hardened substance, which hardened substance binds the layers together and is disposed in a spatial pattern that infiltrates the layers;

wherein the substrate layers have at least one material property that is different than any material property of the hardened substance.

12. The apparatus of claim 11, further comprising an artificial pressure source, the pressure source being configured for applying pressure to one or more of the layers.

13. The apparatus of claim 12, wherein the pressure is applied during softening of the powder.

14. The apparatus of claim 11, further comprising one or more actuators, the one or more actuators being configured for translating one or more of the powder and the layers.

15. The apparatus of claim 11, further comprising an additional actuator, the additional actuator being configured for translating the applicator into different positions while the applicator selectively deposits the powder.

16. The apparatus of claim 11, further comprising a processor, the processor being configured for outputting control signals to control the applicator and heating element.

17. The apparatus of claim 11, wherein the processor is adapted to output control signals to control the selectively depositing of powder for each of the at least some substrate layers, respectively, in accordance with digital data that specifies different slices, respectively, of the 3D object.

18. The apparatus of claim 11, further comprising a container, the container being configured for containing a liquid, which liquid includes a solvent or degrading material that is used for removing material from the at least some negative regions.

19. Apparatus for fabricating a 3D object, which object comprises a stack of substrate layers that have been infiltrated by a hardened material, the apparatus comprising, in combination:

an applicator, the applicator being configured for positioning powder on the layers; and

means for transforming the powder into a substance that flows and then hardens into the hardened material, which hardened material binds the layers together and is disposed in a spatial pattern that infiltrates at least one positive region in a set of the layers and does not infiltrate at least one negative region in the set;

wherein the substrate layers have at least one material property that is different than any material property of the hardened substance.

20. An article of manufacture comprising a plurality of layers that are infiltrated by and bound together by a hardened material, wherein the hardened material comprises either a thermoplastic or thermosettable plastic and exhibits a set of one or more characteristics, which set is sufficient for distinguishing the hardened material as having formed as a result of powder positioned on the layers, respectively, at least partially softening and then hardening.

21. The article of claim 20, wherein the set of characteristics comprises a pattern resulting from at least some grains of powder not completely softening.

22. The article of claim 20, wherein the set of characteristics comprises a pattern resulting from a first grain of powder flowing, after at least partially softening, more viscously than another grain of powder flows, after at least partially melting, or from part of the first grain flowing more viscously, after at least partially softening, than another part of the first grain flows, after partially softening.

23. The article of claim 20, wherein the set of characteristics comprises a crystalline or amorphous structure resulting from incomplete or nonhomogeneous melting of grains of powder.

24. The article of claim 21, wherein the substrate layers are woven.

25. The article of claim 21, wherein the substrate layers are woven and fibrous.

26. The article of claim 21, wherein the substrate layers are non-woven.

27. The article of claim 21, wherein the article includes more than one hardened material, each of which has a different shade or color.

28. An article of manufacture comprising a stack of substrate layers that are infiltrated by a hardened material, wherein an exterior surface of the hardened material has a spatial resolution of 60 or more dots per centimeter in at least one dimension, and wherein the hardened material comprises a thermoplastic, which thermoplastic has an viscosity of 50 or more centipoise at 50 degrees centigrade above the thermoplastic'"'"'s melting temperature.

29. An article of manufacture comprising a plurality of substrate layers that are infiltrated by and bound together by a hardened material, wherein an exterior surface of the hardened material has a spatial resolution of 170 or less microns in at least one dimension, and wherein the hardened material comprises a thermoplastic, which thermoplastic has a melt flow rate of at least 70 grams/10 minutes.

30-34. -34. (canceled)