US 11,840,014 B2
Automated 3D-printing of hollow objects
Yoav Bressler, Tel-Aviv (IL); Yaniv Shitrit, Ashkelon (IL); and Naftali Emanuel Eder, Kiryat Gat (IL)
Assigned to STRATASYS LTD., Rehovot (IL)
Appl. No. 17/278,589
Filed by STRATASYS LTD., Rehovot (IL)
PCT Filed Sep. 25, 2019, PCT No. PCT/IL2019/051061
§ 371(c)(1), (2) Date Mar. 22, 2021,
PCT Pub. No. WO2020/065650, PCT Pub. Date Apr. 2, 2020.
Claims priority of provisional application 62/736,473, filed on Sep. 26, 2018.
Prior Publication US 2021/0347108 A1, Nov. 11, 2021
Int. Cl. B29C 64/118 (2017.01); B33Y 10/00 (2015.01); B33Y 80/00 (2015.01); B29C 64/386 (2017.01); B29C 64/40 (2017.01); B33Y 50/00 (2015.01); B29L 24/00 (2006.01)
CPC B29C 64/118 (2017.08) [B29C 64/386 (2017.08); B29C 64/40 (2017.08); B33Y 10/00 (2014.12); B33Y 50/00 (2014.12); B33Y 80/00 (2014.12); B29L 2024/00 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method for creating an internal support construction in a hollow 3D object model, said method comprising:
computing a skeleton of the hollow 3D object model by:
(i) representing the hollow 3D object model with approximated cylindrical sections;
(ii) calculating the axis of each of the approximated cylindrical sections; and
(iii) connecting the calculated axes;
deriving a central line of the hollow 3D object model, by simplifying the computed skeleton according to specified requirements including at least one of curvature radius thresholds, twisting threshold and length threshold;
calculating a reference line along an inner surface of the hollow 3D object model, by maintaining a distance of the reference line from the central line within specified boundaries; and
creating the internal support construction by filling the hollow 3D object model with support material that comprises a thread defined with respect to the central line and to the reference line, and with filling material surrounding the thread,
wherein said method is carried out by at least one computer processor.