Support Structures and Deposition Techniques for 3D Printing

• US 20130307193A1
• Filed: 05/17/2013
• Published: 11/21/2013
• Est. Priority Date: 05/18/2012
• Status: Active Grant

• Current Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Original Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Inventors: Johnson, Martin Alan, Manners, Chris Roberts, Edwards, Andrew
• Granted Patent: US 9,469,057 B2
• Time in Patent Office: Days
• US Class Current: 264/401
• CPC Class Codes: B29C 37/0003 Discharging moulded articles from the mould constructions for removing the articles B29C33/44
• 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 64/124 using layers of liquid which are selectively solidified
• CPC Class Codes: B29C 64/245 Platforms or substrates support structures intended to be sacrificed after manufacture B29C64/40
• 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 2029/04 PVOH, i.e. polyvinyl alcohol B29K2031/04 takes precedence
• CPC Class Codes: B29K 2033/04 Polymers of esters
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: C08G 73/0233 Polyamines derived from (poly)oxazolines, (poly)oxazines or having pendant acyl groups
• CPC Class Codes: C08L 29/04 Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
• CPC Class Codes: C08L 79/02 Polyamines
• CPC Class Codes: C09J 129/04 Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
• CPC Class Codes: C09J 129/10 Homopolymers or copolymers of unsaturated ethers C09J135/08 takes precedence
• CPC Class Codes: C09J 133/08 Homopolymers or copolymers of acrylic acid esters
• CPC Class Codes: C09J 177/00 Adhesives based on polyamides obtained by reactions forming a carboxylic amide link in the main chain based on polyhydrazides C09J179/06; based on polyamide-imides C09J179/08; Adhesives based on derivatives of such polymers
• CPC Class Codes: C09J 179/00 Adhesives based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen, with or without oxygen, or carbon only, not provided for in groups C09J161/00 - C09J177/00
• CPC Class Codes: C09J 179/02 Polyamines

Abstract

There is provided a support structure for use with 3D printing of objects from computer-aided designs. The support structures include fine points that contact the down-facing surfaces of the 3D object being printed in order to adequately support the 3D object while also being adapted for easy removal after the 3D print process is complete. The fine points are possible by controlling the operation of the dispenser to provide a precise amount of material in a precise location. The dispenser jumps from a first fine point to a second fine point by retracting the print material after the first fine point is printed and then moving the dispenser vertically relative to the first fine point before the dispenser is moved horizontally to the second fine point.

Claims

1. A method of printing a support structure for supporting a three dimensional (3D) object during a print process, the method comprising:

dispensing print material on a print pad to define a lower portion of the support structure;

dispensing print material along an upper portion of the support structure to define fine points, wherein the fine points define an interface between the support structure and the 3D object to be printed; and

jumping the dispenser between fine points to minimize or eliminate unintentional dispensing of print material between fine points, wherein jumping the dispenser comprises;

retracting the print material from the exit of the dispenser after a first fine point has been printed;

moving the dispenser vertically away from the first fine point;

moving the dispenser horizontally to the location of a second fine point;

moving the dispenser vertically toward the location of the second fine point; and

dispensing print material to print the second fine point.

2. A method according to claim 1, wherein moving the dispenser vertically away from the first fine point begins after the print material has been retracted from the exit of the dispenser.

3. A method according to claim 1 wherein moving the dispenser vertically comprises keeping the dispenser vertically stationary and moving the print pad relative to the dispenser.

4. A method according to claim 1 wherein moving the dispenser vertically comprises keeping the print pad vertically stationary and moving the dispenser relative to the print pad.

5. A method according to claim 1, wherein the fine points define a diameter that is one times to three times the diameter of the exit of the dispenser.

6. A method according to claim 1, wherein moving the dispenser horizontally defines a jump distance of 1 mm to 5 mm.

7. A method according to claim 1, wherein moving the dispenser horizontally defines a jump distance of about 2 mm.

8. A method according to claim 1, wherein the fine point defines an average diameter of about 1 mm or less.

9. A method according to claim 1, wherein the fine point is between 0.4 mm and 1.0 mm long in the direction of travel of the dispenser and about 1.0 and 2.0 mm wide in a direction orthogonal to the direction of travel of the dispenser.

10. A method according to claim 1, wherein the fine point is about 0.5 mm long in the direction of travel of the dispenser and about 1.2 mm wide in a direction orthogonal to the direction of travel of the dispenser.

11. A method according to claim 1, wherein the support structure is printed from the same material that the 3D object is printed.

12. A method according to claim 1, wherein the lower portion of the support structure is a raft.

13. A method according to claim 1, wherein the support structure comprises at least one of columns, curtains, and scaffolding between the lower portion and the upper portion of the support structure.

14. A method according to claim 1, wherein jumping the dispenser between fine points is repeated for two or more layers prior to printing of a down-facing surface of the 3D object above the fine points.

15. A method according to claim 1, wherein moving the dispenser vertically toward the location of the second fine point comprises a first motion in a direction away from the location of the second fine point.

16. A method according to claim 15, wherein the first motion is in a direction orthogonal to a straight line between the first fine point and the second fine point.

17. A method according to claim 15, wherein the first motion is in a direction opposite a straight line between the first fine point and the second fine point.

18. A method according to claim 15, wherein the first motion is in a random direction relative to a straight line between the first fine point and the second fine point.

19. A method according to claim 1, wherein the dispenser comprises a heated nozzle.

20. A method according to claim 1, wherein the print material is supplied to the heated nozzle in a solid state and is dispensed from the heated nozzle in a generally liquid state.