Methods and apparatus for multiple material spatially modulated extrusion-based additive manufacturing

Patent metadata

Field	Value
Publication number	US-2016009029-A1
Application number	US-201514796722-A
Country	US
Kind code	A1
Filing date	Jul 10, 2015
Priority date	Jul 11, 2014
Publication date	Jan 14, 2016
Grant date	—

Abstract

Methods and apparatus for multi-material extrusion-based additive manufacturing is described in which material composition and/or color can be varied locally to create abrupt transitions or controlled gradients, and in which objects may be fabricated from thermoset materials.

First claim

What is claimed is:

1 . A multi-material additive manufacturing method for fabricating objects, the method comprising:
providing an extrusion printhead comprising a chamber, an orifice, at least two material flow channels communicating with the chamber, and a plunger able to controllably move within the chamber; advancing a first material into the chamber through a first material flow channel; extruding the first material through the orifice to form a first extrudate; advancing the plunger into the chamber to substantially purge the first material; withdrawing the plunger; advancing a second material into the chamber through a second flow material channel; extruding the second material through the orifice to form a second extrudate, wherein the second extrudate comprises substantially only the second material and substantially none of the first material.

2 . The method of claim 1 wherein the rate of advancement of the first material is decreased and the rate of advancement of the plunger increased when the volume of the first material in the chamber is adequate to complete the first extrudate.

3 . The method of claim 1 wherein the advancing the first material and the extruding the first material are substantially simultaneous.

4 . The method of claim 1 wherein the extruding the first material and the advancing the plunger are substantially simultaneous.

5 . The method of claim 1 wherein at least a portion of the plunger and the chamber are shaped according to geometric solids selected from the group consisting of spheres, cones, and cylinders.

6 . The method of claim 1 wherein the withdrawing occurs subsequent to moving the orifice away from the extrudate.

7 . A multi-material additive manufacturing method for fabricating objects, the method comprising:
providing an extrusion printhead comprising a chamber, an orifice, at least two material flow channels communicating with the chamber, and a rotating element; advancing at least two materials into the chamber through separate material flow channels to contact the rotating element; rotating the element to mix the materials; and depositing the mixed materials through the orifice to form an extrudate, wherein the extrudate comprises a mixture of the at least two materials.

8 . The method of claim 7 wherein the rotating element is a plunger able to advance into and substantially fill the chamber.

9 . The method of claim 7 wherein the at least two materials differ in visual appearance.

10 . The method of claim 7 wherein the at least two materials are components of a silicone elastomer.

11 . The method of claim 7 wherein a volume of the first material advanced is different in magnitude from a volume of the second material advanced.

12 . The method of claim 11 wherein the magnitudes vary continuously in time as the extrudate is formed.

13 . The method of claim 7 where the rotating element can also translate within the chamber and substantially purge material from the chamber.

14 . An additive manufacturing method for fabricating objects, the method comprising:
providing an extrusion printhead comprising at least one material flow channel, an orifice, and an energy source; advancing at least one material requiring energy to cure through the at least one material flow channel and extruding it through the orifice to form an extrudate; exposing the extrudate to energy from the energy source upon extrusion, wherein the extrudate is substantially cured.

15 . The method of claim 14 wherein the energy source is a jet of heated gas.

16 . The method of claim 14 wherein the energy source is infrared light.

17 . The method of claim 14 wherein the energy source is a heated surface.

18 . The method of claim 14 wherein the energy source is light.

19 . The method of claim 14 wherein the printhead moves and the extrudate is deposited along a toolpath and wherein the exposing occurs to a region of the extrudate that has just been deposited.

20 . The method of claim 14 wherein the energy source rotates around the orifice relative to the fabricated object.

21 . The method of claim 14 wherein the energy source surrounds the orifice.

Assignees

• Univ Southern Methodist

Inventors

• Cohen Adam
• Krueger Paul
• Son David

Classifications

• B33Y10/00

  Processes of additive manufacturing · CPC title

• B29K2083/00

  Use of polymers having silicon, with or without sulfur, nitrogen, oxygen, or carbon only, in the main chain, as moulding material · CPC title

• B29K2995/0021

  Multi-coloured · CPC title

• B29C64/209

  Heads; Nozzles · CPC title

• B29C64/264

  Arrangements for irradiation · CPC title