Material deposition system for additive manufacturing

Patent metadata

Field	Value
Publication number	US-2017120513-A1
Application number	US-201514926645-A
Country	US
Kind code	A1
Filing date	Oct 29, 2015
Priority date	Oct 29, 2015
Publication date	May 4, 2017
Grant date	—

Abstract

A material deposition system for additive manufacturing including an extruder and a measuring device for measuring the viscosity and/or other rheological properties of a build material contained within the extruder. The measuring device may provide feedback to a controller for controlling one or more parameters depending on the measured viscosity and/or other rheological properties of the build material within the extruder. Two or more feed materials may be supplied to the extruder and a mixing device may be configured to mix the feed materials within the extruder to create a blended deposition material. The mixing device may be operatively coupled to the measuring device for simultaneously measuring the viscosity and/or other rheological properties of the materials during mixing. The controller may be configured to independently control one or more parameters associated with the materials depending on the viscosity and/or other rheological properties measured by the measuring device.

First claim

1 . A material deposition system for additive manufacturing comprising:
an extruder having:
two or more input ports for receiving two or more feed materials,
a mixing chamber for receiving the two or more feed materials supplied from the two or more input ports,
a mixing device for mixing the two or more feed materials in the mixing chamber to create a blended deposition material, and
an extrusion port for extruding the blended deposition material;
a measuring device configured to measure the viscosity and/or other rheological properties of the two or more feed materials and/or the blended deposition material in the mixing chamber; and a controller configured to control one or more parameters associated with the two or more feed materials and/or the blended deposition material depending on the viscosity and/or other rheological properties measured by the measuring device.

2 . The material deposition system according to claim 1 , wherein the mixing device includes a static mixer.

3 . The material deposition system according to claim 1 , wherein the mixing device includes a dynamic mixer.

4 . The material deposition system according to claim 1 , wherein the mixing device is operatively coupled to the measuring device.

5 . The material deposition system according to claim 4 , wherein the mixing device is integral with the measuring device.

6 . The material deposition system according to claim 1 , wherein the measuring device includes a viscometer.

7 . The material deposition system according to claim 6 , wherein the mixing device includes a dynamic mixer; and
wherein the viscometer is operatively coupled to the dynamic mixer for measuring the torsional forces generated during the mixing of the two or more feed materials and/or the mixing of the blended deposition material.

8 . The material deposition system according to claim 1 , wherein the measuring device includes a rheometer.

9 . The material deposition system according to claim 8 , wherein the mixing chamber is cylindrical and wherein the mixing device is spaced from an interior surface of the mixing chamber to define an annulus therebetween; and
wherein the rheometer is operatively coupled to the mixing device for measuring the torsional forces generated during the mixing of the two or more feed materials and/or the mixing of the blended deposition material in the annulus.

10 . The material deposition system according to claim 1 , further comprising one or more heating elements configured to heat the two or more feed materials and/or the blended deposition material.

11 . The material deposition system according to claim 10 , wherein the controller includes a temperature controller configured to control temperature as one of the one or more parameters of the controller;
wherein the temperature controller is operatively coupled to the one or more heating elements, the temperature controller being configured to control temperature of the two or more feed materials and/or the blended deposition material depending on the viscosity and/or other rheological properties measured by the measuring device.

12 . The material deposition system according to claim 11 , wherein the extruder includes two or more liquefication passages, each of the liquefication passages being associated with a respective one of the two or more input ports for receiving a respective one of the two or more feed materials;
wherein each of the liquefication passages is in thermal communication with a corresponding heating element for heating and liquefying the respective feed materials, each of the liquefication passages being configured to deliver the respective liquefied feed materials downstream toward the mixing chamber; and wherein the temperature controller is operatively coupled to each of the heating elements to independently control temperature of each of the two or more feed materials in the respective liquefication passages depending on the viscosity and/or other rheological properties measured by the measuring device.

13 . The material deposition system according to claim 12 , further including a chamber heating element in thermal communication with the mixing chamber for heating the blended deposition material,
wherein the temperature controller is operatively coupled to the chamber heating element to control temperature of the blended deposition material depending on the viscosity and/or other rheological properties measured by the measuring device.

14 . The material deposition system according to claim 1 , further comprising two or more actuators, each of the actuators being associated with a respective one of the two or more feed materials for feeding the respective feed materials into the extruder;
wherein the controller includes a feed controller configured to control feed rate as one of the one or more parameters of the controller; and wherein the feed controller is operatively coupled to each of the two or more actuators for independently controlling feed rate of each of the two or more feed materials into the mixing chamber depending on the viscosity and/or other rheological properties measured by the measuring device.

15 . The material deposition system according to claim 1 , wherein the controller includes a mix speed controller configured to control speed of the mixing device depending on the viscosity and/or other rheological properties measured by the measuring device.

16 . The material deposition system according to claim 1 , wherein the controller includes a flow controller configured to control flow rate of the blended deposition material extruded from the extrusion port depending on the viscosity and/or other rheological properties measured by the measuring device.

17 . The material deposition system according to claim 1 , wherein at least one of the two or more feed materials is different from another one of the two or more feed materials for creating different compositions of the blended deposition material.

18 . An additive manufacturing apparatus comprising:
a build platform, and the material deposition system according to claim 1 .

19 . An additive manufacturing apparatus comprising:
an extruder having an input port for receiving a build material, an extrusion port for extruding the build material, and a chamber interposed between the input port and the extrusion port for liquefying the build material; a measuring device configured to measure the viscosity and/or other rheological properties of the liquefied build material contained within the chamber; and a controller configured to control one or more parameters depending on the viscosity and/or other rheological properties of the liquefied build material measured by the measuring device.

20 . A method for fabricating a three-dimensional article comprising:
supplying two or more feed materials in a flowable state to a chamber of an extrusion head; mixing the two or more flowable feed materials in the chamber to create a blended deposition material; measuring the viscosity and/or other rheological properties of the two or more flowable feed materials or the blended deposition material; and controlling one or more parameters associated with the two or more flowable feed materials and/or the blended deposition material depending on the measured viscosity and/or other rheological properties of the two or more flowable feed materials or the blended deposition material; and dispensing the blended deposition material from the extrusion head.

Assignees

• Raytheon Co

Inventors

• Brennan Michael

Classifications

• B29C64/118

  using filamentary material being melted, e.g. fused deposition modelling [FDM] · CPC title

• B29C64/393

  for controlling or regulating additive manufacturing processes · CPC title

• B29C48/285

  Feeding the extrusion material to the extruder · CPC title

• B33Y30/00

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title

• B29C2948/922

  Viscosity; Melt flow index [MFI]; Molecular weight · CPC title