Selective deposition modeling method and apparatus for forming three-dimensional objects and supports

• US 6,508,971 B2
• Filed: 08/06/2001
• Issued: 01/21/2003
• Est. Priority Date: 09/27/1995
• Status: Expired due to Term

• Current Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Original Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Inventors: Smalley, Dennis R., Hull, Charles W., Lockard, Michael S., Leyden, Richard N., Merot, Christian M., Kerekes, Thomas A., Bedal, Bryan J. L., Fedchenko, Richard P., Pang, Thomas H., Almquist, Thomas A., That, Dinh Ton, Thayer, Jeffrey S., Earl, Jocelyn M.
• Primary Examiner(s): Tentoni, Leo B.
• Application Number:
  US09/924,433
• Publication Number:
  US 20020008335A1
• Time in Patent Office: 533 Days
• Field of Search: 264/40.1, 264/308, 264/401, 264/408, 425/135, 425/174.4, 425/375, 347/1, 347/20, 347/44, 347/54, 347/85, 347/88, 347/99, 700/119, 700/120
• US Class Current: 264/401
• CPC Class Codes: B29C 41/12 Spreading-out the material on a substrate , e.g. on the surface of a liquid
• CPC Class Codes: B29C 41/36 Feeding the material on to the mould, core or other substrate
• 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 64/112 using individual droplets, e.g. from jetting heads
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 40/00 Auxiliary operations or equipment, e.g. for material handling
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes

Abstract

A variety of support structures and build styles for use in Rapid Prototyping and Manufacturing systems are described wherein particular emphasis is given to Thermal Stereolithography, Fused Deposition Modeling, and Selective Deposition Modeling systems, and wherein a 3D modeling system is presented which uses multijet dispensing and a single material for both object and support formation.

Claims

1. A method of creating a three-dimensional object by depositing a build material on a working surface from a plurality of dispensing orifices in a print head in a rapid prototyping and manufacturing system to form multiple layers of a three-dimensional object, the method comprising the steps of:

a) establishing a relative position between the print head and the working surface;

b) selectively dispensing the build material from the dispensing orifices of the print head while providing relative movement between the print head and working surface in a first scanning direction along a first scan path;

c) re-positioning the relative position between the print head and the working surface in a second direction angled to the first scanning direction;

d) selectively dispensing the build material from the dispensing orifices of the print head while providing relative movement between the print head and working surface in the first scanning direction along a second scan path offset from the first scan path; and

e) repeating steps a)-d) to form the multiple layers of the three-dimensional object until the three-dimensional object is formed.

2. The method of claim 1 wherein the build material is curable upon exposure to radiation, the method further comprising the step of:

exposing the dispensed build material to radiation to cure the layers of the three-dimensional object.

3. The method of claim 2 wherein the build material includes a photopolymer that is curable upon exposure to ultraviolet radiation.

4. The method of claim 2 wherein the step of exposing the dispensed build material to radiation is done for each layer after each layer has been dispensed.

5. A method of claim 1 wherein after a layer is formed the working surface is then established on the just formed layer for forming a new layer, the method further comprising the step of:

re-establishing the relative position between the print head and the new working surface on the just formed layer.

6. The method of claim 5 wherein the step of re-establishing the relative position is achieved by moving the print head to compensate for the thickness of the just formed layer.

7. The method of claim 5 wherein the step of re-establishing the relative position is achieved by moving a build platform to compensate for the thickness of the just formed layer, the three-dimensional object being formed on the build platform.

8. A method of claim 1 wherein the plurality of orifices establish an elongated dispensing pattern having an axis extending generally along the second direction.

9. A method of claim 8 wherein the orifices are equally spaced at a given distance measured in a direction along the second direction, and wherein the step of re-positioning the relative position between the print head and the working surface in the second direction in done by shifting the relative position in equal increments of the given distance.

10. The method of claim 8 wherein the orifices are equally spaced at a given distance measured in a direction along the second direction, the method further comprising the step of:

establishing a saber angle between the axis of the elongated dispensing pattern and the second direction in order to adjust the given distance measured to achieve a desired resolution.

11. The method of claim 1 further comprising the step of:

controlling the dispensing of the orifices of the print head to achieve a uniform thickness of the build material in the layers.

12. The method of claim 1 further comprising the step of:

indexing the relative position between the print head and the working surface along the second direction an amount at least equal to the width between the outermost orifices of the print head measured in a direction along the second direction.

13. The method of claim 12 wherein the step of indexing is executed as needed to form any layer of the three-dimensional object.

14. The method of claim 12 wherein the step of selectively dispensing the build material while providing relative movement along the first scan path is completed at least once prior to the step of indexing the relative position between the print head and the working surface along the second direction.

15. The method of claim 14 wherein the step of selectively dispensing the build material while providing relative movement along the first scan path is completed eight times prior to the step of indexing the relative position between the print head and the working surface along the second direction.

16. The method of claim 1 further comprising a plurality of print heads for dispensing the material on the working surface to form the three-dimensional object.

17. The method of claim 16 wherein the print heads are arrayed end to end along the second direction.

18. The method of claim 16 wherein the print heads are arrayed back to back along the first scan path.

19. The method of claim 16 wherein the print heads are offset from one another in the second direction.

20. The method of claim 1 wherein each dispensing orifice selectively dispenses the build material along a raster line, the raster lines comprising a plurality of raster lines.

21. The method of claim 20 wherein the step of re-positioning the relative position between the print head and the working surface in the second direction causes each dispensing orifice to dispense the build material along an alternate raster line of the plurality of raster lines to compensate for orifices that are not dispensing correctly.

22. The method of claim 20 wherein the step of re-positioning the relative position between the print head and the working surface in the second direction causes each dispensing orifice to dispense the build material along a different raster line that is not part of the plurality of raster lines to compensate for orifices that are not dispensing correctly.

23. The method of claim 1 further comprising the step of:

detecting optically any misfiring orifices.

24. The method of claim 1 further comprising the step of:

calibrating the plurality of orifices.

25. The method of claim 24 wherein the step of calibrating the orifices comprises:

depositing a layer by selectively dispensing build material from all of the dispensing orifices;

detecting optically any misfiring orifices;

compensating for any misfiring orifices detected.

26. The method of claim 25 wherein a test pattern is formed when depositing the layer of the calibration step.

27. The method of claim 25 wherein the step of compensating for any misfiring orifices comprises:

putting the misfiring orifices through a reactivation routine.

28. The method of claim 25 wherein the step of compensating for any misfiring orifices is accomplished by overprinting.

29. The method of claim 1 further comprising:

compensating for any misfiring orifices when forming each layer to achieve a uniform thickness for each layer.

30. The method of claim 1 wherein the step of re-positioning the relative position between the print head and the working surface in the second direction is achieved by moving the print head.

31. The method of claim 1 wherein the step of re-positioning the relative position between the print head and the working surface in the second direction is achieved by moving a build platform, the build platform supporting the layers of the three-dimensional object being formed and therein controlling the location of the working surface.

32. The method of claim 31 wherein the step of re-positioning the relative position between the print head and the working surface is further achieved by moving the print head along with the build platform.

33. The method of claim 1 wherein the step of re-positioning the relative position between the print head and working surface is further accomplished by:

rotating respectively the print head with the working surface in order to alter the direction of the first scan path.

34. The method of claim 23 wherein the print head is rotated with respect to the working surface.

35. The method of claim 33 wherein a build platform is rotated with respect to the print head, the build platform supporting the just formed layers of the three-dimensional object and therein the location of working surface.

36. A method of forming a three-dimensional object layer by layer in successive layers of material are selectively formed in accord with data defining the object, wherein each layer is formed by selective deposition of a flowable material comprising the following steps:

a) moving a printhead in a first scanning direction, the printhead having a plurality of orifices extending at an angle to the first scanning direction,

b) selectively depositing material from the orifices while moving the printhead in the first scanning direction along a first scan path;

c) moving the printhead in a second direction angled to the first scanning direction; and

d) selectively depositing material from the orifices while moving the printhead in the first scanning direction along a second scan path offset from the first scan path; and

e) repeating steps a)-d) to form the successive layers of the three-dimensional object until the three-dimensional object is formed.

37. The method according to claim 36 wherein the second scan path overlaps the first scan path.

38. The method according to claim 36 wherein the material is curable by exposure to radiation, the method further comprising the step of:

curing the material by exposure to radiation.

39. The method according to claim 36 wherein the orifices extend transverse to the first scanning direction.

40. The method according to claim 38 wherein the step of curing the material is achieved by exposing the material to ultra-violet (UV) radiation.

41. The method according to claim 38 wherein the material is a photopolymer that is cured by exposure to radiation.

42. The method according to claim 41 wherein the step of curing the material is performed for each deposited layer prior to depositing the next layer.

43. The method according to claim 36 wherein material is not selectively deposited when the printhead is moving in the second direction.

44. The method according to claim 36 wherein a plurality of printheads are used to selectively deposit the material.

45. The method according to claim 36 wherein the second direction is transverse to the first scanning direction.

46. The method according to claim 44 wherein a plurality of printheads are arrayed end to end extending in the second direction and used to selectively deposit the material.

47. The method according to claim 44 wherein a plurality of printheads are arrayed back to back in the first direction and used to selectively deposit the material.

48. The method according to claim 47 wherein a plurality of printheads are offset from one another in the second direction and used to selectively deposit the material.

49. The method of claim 36 wherein the step of moving the printhead in the first scanning direction is achieved along a plurality of parallel raster lines.

50. The method of claim 49 wherein the step of moving the printhead in the second direction at an angle to the first direction is achieved at a distance equal to at least one raster line.

64. The method of claim 36 further comprising the step of:

detecting optically any misfiring orifices.

65. The method of claim 36 further comprising the step of:

calibrating the plurality of orifices.

66. The method of claim 65 wherein the step of calibrating the orifices comprises:

depositing a layer by selectively dispensing build material from all of the dispensing orifices;

detecting optically any misfiring orifices; and

compensating for any misfiring orifices detected.

67. The method of claim 66 wherein a test pattern is formed when depositing the layer of the calibration step.

68. The method of claim 66 wherein the step of compensating for any misfiring orifices comprises:

putting the misfiring orifices through a reactivation routine.

69. The method of claim 66 wherein the step of compensating for any misfiring orifices is accomplished by overprinting.

70. The method of claim 36 further comprising:

compensating for any misfiring orifices when forming each layer to achieve a uniform thickness for each layer.

51. Apparatus for forming a three-dimensional object in which successive layers of material are selectively formed in accordance with data defining the object, comprising:

a printhead,

means for moving the printhead in a first scan direction and in a second direction angled to said first direction,

the printhead having a plurality of orifices extending in a direction angled to the first direction, the orifices being selectively activatable in accord with data supplied to the printhead to dispense material, and

control means coupled to the means for moving to control movement thereof and to the printhead to control selective activation thereof, the control means programmed to control the means for moving the printhead, the control means effecting;

a) movement of the printhead in the first direction along a first scan path while selectively activating the printhead to dispense material,

b) movement of the printhead in the second direction, and

c) movement of the printhead in the first direction along a second scan path offset from said first scan patch while selectively activating the printhead, and wherein the second scan path of the printhead overlaps the first scan path.

52. The apparatus according to claim 51 further comprising a source of flowable material connected to the printhead for dispensing to permit selective depositing of the flowable material from the orifices.

53. The apparatus according to claim 52 wherein the flowable material dispensed by the printhead is a radiation-curable material.

54. The apparatus according to claim 53 in which said flowable material dispensed by the printhead is curable by exposure to ultra-violet (UV) radiation.

55. The apparatus according to claim 54 wherein the flowable material dispensed by the printhead is a photopolymer.

56. The apparatus according to claim 55 wherein the photopolymer dispensed by the printhead includes a photo-initiator.

57. The apparatus according to claim 53 further comprising means for delivering radiation for curing the flowable material selectively deposited in each layer.

58. The apparatus according to claim 51 wherein the means for moving the printhead moves the printhead in the second direction transverse to the first scan direction.

59. The apparatus according to claim 51 further comprising using a plurality of printheads to dispense the material.

60. The apparatus according to claim 59 further comprising the plurality of printheads are arrayed end to end extending in the second direction.

61. The apparatus according to claim 59 further comprising the plurality of printheads are arrayed back to back in the first direction.

62. The apparatus according to claim 61 further comprising the plurality of printheads being offset from one another in the second direction.

63. The apparatus according to claim 51 further comprising the plurality of orifices extend transversely to the first scan direction.

71. The apparatus of claim 51 further comprising a scanner for detecting optically any misfiring orifices.

72. The apparatus of claim 71 wherein the control means calibrates the plurality of orifices.

73. The apparatus of claim 72 wherein the control means puts the misfiring orifices detected by the scanner through a reactivation routine.

74. The apparatus of claim 72 wherein the control means compensates for any misfiring orifices by overprinting.