IPC分类号：
A01J21/00 | B29C48/92
当前申请(专利权)人：
FENNER U.S., INC.
原始申请(专利权)人：
FENNER U.S., INC.
当前申请(专利权)人地址：
Manheim Division 311 W. Stiegel Street,Manheim, PA 17545,US
发明人：
HESTON, STEPHEN, F. | TOTARO, ANNA
代理机构：
HARRISON, ROBERT JOHN
摘要：
An apparatus for forming an object by an additive process, commonly referred to as 3-D printing, is provided. The apparatus includes a filament comprising a series of irregularities along the length of the filament, a nozzle depositing a layer of melted material onto a surface and a feeder feeding the filament to the nozzle. A heating element melts the filament and a controller controls the position of the nozzle in a plane to control the configuration of the layer of melted material deposited by the nozzle. Additionally, a method for forming polymer filament used in 3-D printing devices is also provided. The method includes the steps of melting a polymer, selecting an extrusion characteristic calculated to induce a polymer flow instability and extruding the melted polymer using the selected extrusion characteristic to produce an extrusion having distortions created by the polymer flow instability.
技术问题语段：
The technical problem addressed in this patent is the difficulty of using rigid materials in additive manufacturing machines like fused deposition modeling (FDM) because they tend to be brittle at room temperature. The invention provides low durometer elastomer materials that work efficiently with known additive manufacturing machines and improve the mechanical properties of the resulting products. The invention includes a spool of low durometer elastomer filament with reduced tackiness to improve feeding through the FDM machine. The low durometer filament has a plurality of melt fractures or ridges running transverse the elongated axis of the filament to reduce the coefficient of friction. The invention also includes a method of using a thermoplastic filament with a series of irregularities along its length to produce a three-dimensional object by depositing multiple layers of material.
技术功效语段：
The present invention provides an improved method for creating three-dimensional objects using fused deposition modeling technology. The invention involves the use of low durometer elastomer materials that work efficiently with known additive manufacturing machines. The low durometer materials have improved characteristics, but are rigid enough to cause difficulties in feeding through the machines. The invention solves this problem by providing a spool of low durometer elastomer filament with reduced tackiness to improve feeding through the machines. The elastomer materials have reduced stiffness, making them suitable for a variety of applications. The invention also includes a system for creating three-dimensional objects by depositing multiple layers of material. The system includes an extrusion head for selectively depositing melted material onto a support element. The invention provides an improved method for creating three-dimensional objects using fused deposition modeling technology.
权利要求：
CLAIMS
1 . A system for producing an object by an additive process, comprising:
an elongated filament comprising a series of irregularities along the length of the filament;
a nozzle for depositing a layer of melted material onto a surface;
a feeder for feeding the filament to the nozzle;
a heating element for melting the filament into the melted material;
a controller for controlling the position of the nozzle in a plane to control the configuration of the layer of melted material deposited by the nozzle, wherein the controller controls the operation of the feeder and the position of the nozzle to build a series of layers of melted material to form the object.
2. The system of claim 1 wherein the filament is wound onto a spool.
3. The system of claim 1 or 2 wherein the irregularities comprise extrudate irregularities.
4. The system of claim 3 wherein the filament comprises an extrusion axis extending the length of the filament and the extrudate irregularities comprise a plurality of ridges extending transverse the extrusion axis.
5. The system of claim 4 wherein the filament has a diameter and the
amplitude of the ridges is substantially smaller than the diameter of the filament.
6. The system of claim 4 or 5 wherein the extrudate irregularities comprise melt fractures.
7. The system of any of claims 1 -6 wherein the filament is formed of material having a durometer of less than 50 on the Shore D scale or less than 90 on the Shore A scale.
8. The system of any of claims 1 -7 wherein the filament material comprises thermoplastic urethane or silicone.
9. The system of any of claims 1 -8 wherein the filament comprises a
thermoplastic elastomer.
10. A method for producing an object by an additive process, comprising the steps of :
selecting a feedstock comprising an elongated filament having a series of irregularities along the length of the filament;
feeding the feedstock to a device operable to melt the filament to form a stream of melted material; and
controlling the stream of melted material to build a series of layers to form an object by an additive process.
1 1 . The method of claim 10 wherein the step of selecting a feedstock
comprises selecting a filament wound onto a spool and wherein the step of feeding comprises pulling the filament to unwind the filament from the spool.
12. The method of claim 10 or 1 1 wherein the step of selecting feedstock
comprises selecting a filament having extrudate irregularities.
13. The method of any of claims 10-12 wherein the step of selecting feedstock comprises selecting a filament having an extrusion axis extending the length of the filament and extrudate irregularities comprising a plurality of ridges extending transverse the extrusion axis.
14. The method of any of claims 10-13 wherein the step of selecting feedstock comprises selecting a filament having extrudate irregularities comprising melt fractures forming ridges extending transverse an extrusion axis of the filament.
15. The method of any of claims 10-14 wherein the step of selecting a
feedstock comprises selecting a filament formed of material having a durometer of less than 90 on the Shore A scale or less than 50 on the Shore D scale.
16. The method of any of claims 10-15 wherein the step of selecting a
feedstock comprises selecting a filament formed of a material comprising thermoplastic urethane or silicone.
17. The method of any of claims 10-16 wherein the step of selecting a
feedstock comprises the step of selecting a filament comprising a thermoplastic elastomer.
18. The method of any of claims 15-17 wherein the step of selecting a
feedstock comprises selecting an extruded feedstock having irregularities formed by polymer flow instabilities.
19. The method of claim 18 wherein the irregularities are small amplitude
surface distortions.
20. The method of claim 18 or 19 wherein the irregularities are sharkskin
irregularities.
21 . A method for forming polymer filament for use in an apparatus for
producing an object by an additive process, wherein the method for forming the polymer filament comprises the steps of:
melting a polymer;
selecting an extrusion characteristic calculated to induce a polymer flow instability;
extruding the melted polymer using the selected extrusion characteristic to produce an elongated substantially solid extrusion, wherein the polymer flow instability creates distortions on the surface of the extrusion;
pulling the elongated extrusion;
automatically measuring the cross-sectional characteristic of the elongated extrusion during the step of pulling; and
varying either the step of extruding or the step of pulling in response to the step of measuring.
22. The method of claim 21 wherein the extrusion characteristic is one of
temperature, the rate at which the extrusion is extruded during the step of extruding and the rate at which the extrusion is pulled during the step of pulling.
23. The method of claim 21 or 22 wherein the step of extruding comprises extruding an extrusion having melt fractures along the length of the extrusion.
24. The method of any of claims 21 -23 wherein the step of extruding comprises extruding a filament having a diameter of 1 .75 mm with a tolerance of plus or minus 0.05 mm or 3.0 mm with a tolerance of plus or minus 0.05 mm.
25. The method of any of claims 21 -24 wherein the step of extruding comprises extruding a polyurethane thermoplastic elastomer.
26. The method of any of claims 21 -25 wherein the step of extruding
comprises extruding an extrusion having surface distortions.
27. The method of claim 26 wherein the surface distortions are small amplitude distortions.
28. The method of claim 27 wherein the amplitude of the distortions is substantially smaller that the diameter of the extrusion.
29. The method of claim 27 wherein the surface distortions are sharkskin
distortions.
30. The method of claim 27 wherein the surface distortions comprise a plurality of ridges along the length of the extrusion.
31 . The method of claim 30 wherein the distortions are periodic.
32. The method of any of claims 21 -31 comprising the step of cooling the
extrusion to form a filament having a durometer less than 90 on the Shore A scale or less than 50 on the Shore D scale.
33. A method for producing an object by an additive process, comprising the steps of :
feeding a feedstock comprising an elongated filament having a series of irregularities along the length of the filament into a device operable to melt the filament to form a stream of melted material; and controlling the stream of melted material to build a series of layers to form an object by an additive process.
34. The method of claim 33 comprising the step of selecting a feedstock wound onto a spool and wherein the step of feeding comprises pulling the filament to unwind the filament from the spool.
35. The method of claim 33 or 34 wherein the filament has extrudate
irregularities.
36. The method of any of claims 33-35 wherein the filament has an extrusion axis extending the length of the filament, wherein the filament comprises melt fractures extending transverse the extrusion axis.
37. The method of claim 35 or 36 wherein the extrudate irregularities form ridges extending transverse an extrusion axis of the filament.
38. The method of any of claims 33-37 wherein the filament is formed of
material having a durometer of less than approximately 90 on the Shore A scale or 50 on the Shore D scale.
39. The method of any of claims 33-38 wherein the filament is a thermoplastic elastomer.
40. The method of any of claims 33-39 wherein the filament is formed of a material comprising thermoplastic urethane or silicone.
41 . The method of any of claims 38-40 wherein the feedstock has irregularities formed by polymer flow instabilities.
42. The method of claim 41 wherein the irregularities are small amplitude surface distortions.
43. The method of claim 42 wherein the irregularities are sharkskin
irregularities.
44. A filament for use in an apparatus for producing an object by an additive process, comprising:
an elongated thermoplastic polymeric elastomeric filament having a
substantially round cross-section and a hardness of less than 90 on the Shore A scale;
wherein the filament has a longitudinal axis extending the length of the filament and a plurality of extrudate irregularities are formed along the length of the filament;
wherein the extrudate irregularities project radially transverse the
longitudinal axis to form engagement surfaces to be engaged by a feed element of the apparatus for producing an object by an additive process;
a spool onto which a plurality of convolutions of the filament are wound.
45. The filament of claim 44 wherein the filament is formed of polyurethane.
46. The filament of claim 44 or 45 wherein the extrudate irregularities comprise a plurality of periodic ridges formed along the surface of the filament.
47. The filament of claim 46 wherein the ridges extend around the
circumference of the filament.
48. The filament of claims 47 wherein the extrudate irregularities are sharkskin formations on the surface of the filament.
49. The filament of claim 47 wherein the ridges have an amplitude that is
substantially less than the diameter of the filament.
50. The filament of any of claims 44-49 wherein the extrudate irregularities extend over substantially the entire length of the filament.
51 . The filament of claim 48 or 50 wherein the sharkskin formations extend over substantially the entire surface of the filament.
52. The filament of any of claims 44-51 having a diameter of 1 .75 mm plus or minus 0.05 mm or a diameter of 3.0 mm plus or minus 0.05 mm.