3D printing system for preparing a three-dimensional object

Patent metadata

Field	Value
Publication number	US-12330370-B2
Application number	US-201917270500-A
Country	US
Kind code	B2
Filing date	Aug 26, 2019
Priority date	Aug 30, 2018
Publication date	Jun 17, 2025
Grant date	Jun 17, 2025

Abstract

A three-dimensional printing system for preparing a three-dimensional object made at least partially of an expanded polymer includes a printing device configured to prepare an expandable polymer melt and deposit a strand of expandable, expanding or expanded polymer onto a surface and a three-dimensional movement device for to enable depositing of the strand of expandable, expanding or expanded polymer at a predetermined time at a precise position within the three-dimensional matrix. The printing device includes a feed section at an upstream end of the printing device, a heating section, a pressurizing section, a blowing agent supply line, a mixing section, a cooling section and a terminal printing head section at a downstream end of the printing device including a die configured to deposit the strand of the expandable, expanding or expanded polymer onto the surface.

First claim

The invention claimed is:

1. A three-dimensional printing system for preparing a three-dimensional object made at least partially of an expanded polymer, comprising:
a printer configured to prepare an expandable polymer melt and deposit a strand of expandable, expanding or expanded polymer onto a surface, the printer comprising:
a feed section at an upstream end of the printer,
a heating section,
a pressurizing section,
a blowing agent supply line arranged downstream of the heating section and the pressurizing section,
a mixing section,
a cooling section, and
a terminal printing head section at a downstream end of the printer including a die configured to deposit the strand of the expandable, expanding or expanded polymer onto the surface,
the mixing section and the cooling section being arranged downstream of: the feed section, the heating section, and the pressurizing section,
the blowing agent supply line having at least one discharge end connected with at least one of: the pressurizing section, the mixing section and the cooling section,
the cooling section being a tubular section, which comprises a tube, and a Peltier element, a resistance heater, a heat exchanger or cooling fins disposed on an outer wall of the tube, and
the pressurizing section comprising a piston compressor, a screw compressor or a gear compressor.

2. The three-dimensional printing system in accordance with claim 1 , wherein each of the feed section, the heating section, the mixing section and the cooling section is a tubular section having a same inner diameter between 1 mm and 10 mm.

3. The three-dimensional printing system in accordance with claim 1 , wherein:
the feed section, the heating section, the pressurizing section, the mixing section, cooling section and the printing head are arranged in this order from the upstream end to the downstream end of the printer, or
the feed section, the heating section, the pressurizing section, the mixing section, cooling section and the printing head are arranged from the upstream end to the downstream end of the printer in the following order: feed section followed by the pressurizing section followed by the heating section followed by the mixing section followed by the cooling section followed by the printing head section, or
the feed, heating and pressurizing sections are combined into one section, which is followed by the mixing section which is followed by the cooling section which is followed by the printing head section.

4. The three-dimensional printing system in accordance with claim 1 , wherein the heating section is a tubular section comprising a tube, and cooling fins are disposed on the outer wall of the tube.

5. The three-dimensional printing system in accordance with claim 1 , wherein a wall of the pressurizing section comprises a heating element selected from the group consisting of: a Peltier element, a resistance heater and a heat exchanger.

6. The three-dimensional printing system in accordance with claim 1 , wherein the cooling section is arranged downstream of the mixing section, and the blowing agent supply line has a first discharge end that is connected with the mixing section.

7. The three-dimensional printing system in accordance with claim 1 , wherein the cooling section is arranged upstream of the mixing section, and the blowing agent supply line has a first discharge end that is connected with the cooling section or with the mixing section.

8. The three-dimensional printing system in accordance with claim 1 , wherein the printing head section is a tapered tubular section, the downstream end of the printing head section is tapered so as to form the die, and the upstream end of the printing head section has the same inner diameter as at least one of: the feed section, the heating section, the mixing section, and the cooling section.

9. A method for preparing a three-dimensional object made at least partially of an expanded polymer, the method comprising:
preparing the object in the three-dimensional printing system in accordance with claim 1 .

10. The method in accordance with claim 9 , wherein the method comprises:
melting the polymer so as to obtain the polymer melt,
pressurizing the polymer melt so as to obtain a pressurized polymer melt,
dosing at least one blowing agent into the pressurized polymer melt so as to obtain an expandable pressurized polymer melt,
homogenizing the expandable pressurized polymer melt by passing the polymer melt through at least one mixer and by passing the polymer melt through at least one static mixer so as to obtain a homogenized expandable pressurized polymer melt,
cooling the homogenized, expandable pressurized polymer melt so as to obtain a cooled homogenized expandable pressurized polymer mixture, and
shaping, depositing and foaming the cooled homogenized expandable pressurized polymer mixture by extruding the cooled homogenized expandable pressurized polymer mixture through the die of the printer.

11. The method in accordance with claim 9 , wherein at least one nucleating agent is added to the polymer, and the at least one nucleating agent is added before the melting the polymer or after the melting the polymer, but before the homogenizing the expandable pressurized polymer melt or before the melting the polymer and after the melting the polymer, but before the homogenizing the expandable pressurized polymer melt.

12. The method in accordance with claim 9 , wherein the polymer is selected from the group consisting of: thermoplastic polyurethanes, polyolefins, polyesters, ethylene vinylacetate copolymers, ethylene butyl acrylate copolymers, polystyrenes, polylactic acids, thermoplastic elastomers, nitrile rubbers, copolymers of acrylonitrile and butadiene, polychloroprenes, polyimides, polyvinyl chlorides and combinations of two or more of the aforementioned polymers.

13. The method in accordance with claim 9 , wherein the blowing agent is a physical blowing agent.

14. The method in accordance with claim 9 , wherein the expandable pressurized polymer melt has a temperature of 60 to 270° C. and is pressurized to 2 MPa to 50 MPa.

Assignees

• Sulzer Management Ag

Inventors

• Shields Stephen
• Tammaro Daniele
• Trommsdorff Ulla
• Walker Claudio

Classifications

• B29K2105/048

  Expandable particles, beads or granules · CPC title

• B29C64/295

  Heating elements · CPC title

• B29C64/321

  Feeding · CPC title

• B33Y40/00

  Auxiliary operations or equipment, e.g. for material handling · CPC title

• B33Y30/00

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