Seam concealment for three-dimensional models

• US 8,974,715 B2
• Filed: 06/12/2014
• Issued: 03/10/2015
• Est. Priority Date: 09/23/2009
• Status: Active Grant

• Current Assignee: Stratasys Incorporated
• Original Assignee: Stratasys Incorporated
• Inventors: Hopkins, Paul E., Holzwarth, Donald J.
• Primary Examiner(s): Tentoni, Leo B
• Application Number:
  US14/302,898
• Publication Number:
  US 20140291893A1
• Time in Patent Office: 271 Days
• Field of Search: 264/308, 700/118, 700/119
• US Class Current: 264/308
• CPC Class Codes: B29C 2948/92076 Position, e.g. linear or angular
• CPC Class Codes: B29C 2948/92409 Die; Nozzle zone
• CPC Class Codes: B29C 2948/92428 Calibration, after-treatment, or cooling zone
• CPC Class Codes: B29C 2948/92571 Position, e.g. linear or angular
• CPC Class Codes: B29C 48/09 Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
• CPC Class Codes: B29C 48/21 the layers being joined at their surfaces
• CPC Class Codes: B29C 48/92 Measuring, controlling or regulating
• CPC Class Codes: B29C 64/112 using individual droplets, e.g. from jetting heads
• 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 64/171 specially adapted for manufacturing multiple 3D objects
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B29K 2025/00 Use of polymers of vinyl-aromatic compounds or derivatives thereof as moulding material
• CPC Class Codes: B29K 2055/02 ABS polymers, i.e. acrylonitrile-butadiene-styrene polymers
• CPC Class Codes: B29K 2069/00 Use of PC, i.e. polycarbonates or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2077/00 Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2079/085 Thermoplastic polyimides, e.g. polyesterimides, PEI, i.e. polyetherimides, or polyamideimides; Derivatives thereof
• CPC Class Codes: B29K 2081/06 PSU, i.e. polysulfones; PES, i.e. polyethersulfones or derivatives thereof
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• 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
• CPC Class Codes: G05B 19/4099 : Surface or curve machining, making 3D objects, e.g. desktop manufacturing
• CPC Class Codes: Y10T 428/24777 : Edge feature
• CPC Class Codes: Y10T 428/24802 : Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

A three-dimensional model built with an extrusion-based digital manufacturing system, and having a perimeter based on a contour tool path that defines an interior region of a layer of the three-dimensional model, where at least one of a start point and a stop point of the contour tool path is located within the interior region of the layer.

Claims

1. A method for building a three-dimensional model with an extrusion-based digital manufacturing system having an extrusion head and a controller, the method comprising:

receiving a tool path for a layer of the three-dimensional model by the controller, wherein the received tool path comprises an outgoing segment, an incoming segment, and a contour segment extending between the outgoing segment and the incoming segment, and wherein the incoming segment overlaps the outgoing segment at an intersection; and

moving the extrusion head in a pattern that follows the received tool path to produce a perimeter path of a thermoplastic material for the layer, wherein the perimeter path has a concealed seam at the intersection of the outgoing segment and the incoming segment.

2. The method of claim 1, wherein the perimeter path defines an interior region of the layer, and wherein portions of the perimeter path defined by the outgoing segment of the received tool path and of the incoming segment of the received tool path are at least partially located within the interior region of the layer.

3. The method of claim 1, wherein the overlap of the outgoing segment of the received tool path and the incoming segment of the received tool path defines an X-pattern at the intersection.

4. The method of claim 1, wherein the concealed seam reduces surface porosity for the three-dimensional model.

5. The method of claim 1, and further comprising reducing an amount of material that vertically accumulates at the intersection where the incoming segment of the received tool path overlaps the outgoing segment of the received tool path.

6. The method of claim 1, and further comprising:

generating the tool path with a computer based on a predicted road width for the perimeter path; and

transmitting instructions for the generated tool path to the controller.

7. The method of claim 6, wherein the predicted road width ranges from about 250 micrometers to about 1,020 micrometers.

8. The method of claim 1, wherein a portion of at least one of the outgoing segment of the received tool path and the incoming segment of the received tool path defines a raster pattern.

9. A method for building a three-dimensional model with an extrusion-based digital manufacturing system having an extrusion head and a controller, the method comprising:

generating a tool path with a computer;

transmitting instructions for the generated tool path to the controller;

depositing a thermoplastic material from the extrusion head while moving the extrusion head along the generated tool path to form a perimeter path of a layer of the three-dimensional model, wherein the perimeter path comprises;

an outgoing road portion;

a contour road portion extending from the outgoing road portion; and

an incoming road portion extending from the contour road portion, and overlapping the outgoing road portion with an X-pattern, thereby forming a concealed seam for the layer.

10. The method of claim 9, wherein the perimeter path defines an interior region of the layer, and wherein the outgoing road portion and the incoming road portion are each at least partially located within the interior region of the layer.

11. The method of claim 10, and further comprising depositing the thermoplastic material from the extrusion head while moving the extrusion head along at least one additional tool path to produce at least one additional road located within the interior region of the layer.

12. The method of claim 9, wherein the incoming road portion has a reduced volume of the deposited thermoplastic material at the overlapped X-pattern compared to the outgoing road portion.

13. The method of claim 9, wherein the concealed seam for the layer reduces surface porosity of the three-dimensional model.

14. The method of claim 9, wherein at least one of the outgoing road portion and the incoming road portion also defines a raster pattern.

15. A method for building a three-dimensional model with an extrusion-based digital manufacturing system having an extrusion head and a controller, the method comprising:

moving an extrusion head along an outgoing tool path segment to form an outgoing road portion for a layer of the three-dimensional model;

moving the extrusion head from the outgoing tool path segment along a contour tool path segment to form a contour road portion for the layer; and

moving the extrusion head from the contour tool path segment along an incoming tool path segment to form an incoming road portion for the layer that overlaps the outgoing road portion to form a concealed seam for the layer, and such that the outgoing road portion and the incoming road portion are each at least partially located within an interior region of the layer.

16. The method of claim 15, wherein at least one of the outgoing road portion and the incoming road portion also defines a raster pattern.

17. The method of claim 15, wherein the overlap of the outgoing road portion and the incoming road portion defines an X-pattern.

18. The method of claim 15, wherein the concealed seam reduces surface porosity for the three-dimensional model.

19. The method of claim 15, and further comprising reducing an amount of material that vertically accumulates for the incoming road portion at the overlap of the outgoing road portion and the incoming road portion.

20. The method of claim 15, wherein the outgoing road portion, the contour road portion, and the incoming road portion each comprise a thermoplastic material.