Color switching for three-dimensional printing

• US 9,168,699 B2
• Filed: 09/06/2013
• Issued: 10/27/2015
• Est. Priority Date: 09/07/2012
• Status: Active Grant

• Current Assignee: MakerBot Industries, LLC (Ultimaker BV)
• Original Assignee: MakerBot Industries, LLC (Ultimaker BV)
• Inventors: Pax, Charles E.
• Primary Examiner(s): Del Sole, Joseph S
• Assistant Examiner(s): Nguyen, Thukhanh T
• Application Number:
  US14/020,535
• Publication Number:
  US 20140070461A1
• Time in Patent Office: 781 Days
• Field of Search: 264/129, 264/176.1, 264/40.1, 264/40.7, 264/308, 425/145, 425/150, 425/375, 425/112, 425/113, 700/118, 700/119, 700/120, 226/8, 226/24, 226/26, 226/42, 226/43, 226/45
• US Class Current: 1/1
• 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 64/118 using filamentary material being melted, e.g. fused deposition modelling [FDM]
• CPC Class Codes: B29C 64/321 Feeding
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B29K 2101/12 Thermoplastic materials
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 50/00 Data acquisition or data processing for additive manufacturing
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes

Abstract

By reversing the direction of a first build material fed into an extruder, the first build material can be wholly or partially evacuated from the extruder before a second material is introduced. This approach mitigates transition artifacts and permits faster, more complete changes from one build material to another.

Claims

1. A method comprising:

providing a three-dimensional printer having an extruder with a first input port, a second input port, an extrusion port, and a chamber coupling the first input port, the second input port, and the extrusion port in fluid communication;

driving a first build material through the first input port until the first build material extrudes through the extrusion port;

withdrawing the first build material through the first input port a predetermined amount, wherein the predetermined amount is selected to move a material transition region between the first build material and a second build material out of the chamber but not enough to completely withdraw the first build material from the extruder; and

driving the second build material through the second input port until the second build material extrudes through the extrusion port.

2. The method of claim 1 further comprising heating the chamber to liquefy at least one of the first build material and the second build material.

3. The method of claim 1 wherein the first build material is a different color than the second build material.

4. The method of claim 1 wherein the first build material is of a different type than the second build material.

5. The method of claim 1 wherein the first build material is a plastic.

6. The method of claim 1 wherein the first build material is one or more of ABS, PLA, and PCL.

7. The method of claim 1 wherein the predetermined amount includes an amount of the first build material displacing at least one half the volume of the chamber.

8. The method of claim 1 wherein the predetermined amount includes an amount of the first build material displacing at least the volume of the chamber.

9. The method of claim 1 further comprising withdrawing the first build material concurrently with driving the second build material.

10. The method of claim 1 further comprising withdrawing the second build material through the second input port by a second predetermined amount and driving the first build material through the first input port until the first build material extrudes through the extrusion port.