US-12617157-B2 - Method for manufacturing low modulus articles

Abstract

A method of manufacturing a 3D article includes operating a 3D printing system including an elevator coupled to a vertical movement mechanism, and a distance sensor. The elevator includes an elevator actuator. The vertical movement mechanism is coupled to the elevator. The build platform includes a build plate having a lower surface. The method includes loading the build platform onto the elevator, operating the vertical movement mechanism to lower the lower surface of the build platform into a measurement range with the distance sensor, scanning the distance sensor along a lateral axis, concurrent with scanning the distance sensor, receiving a signal from the distance sensor indicative of a plurality of vertical locations along the lateral axis of the lower surface of the build platform, and operating the elevator actuator to adjust a height of the lower surface of the build platform.

Inventors

• David Sabo
• Grant Draper
• Curtis J. Behrend

Assignees

• 3D SYSTEMS, INC.

Dates

Publication Date

20260505

Application Date

20240208

Claims (20)

1. 1 . A method of manufacturing a three-dimensional (3D) article comprising: providing a 3D printing system including: an elevator configured for translation along a vertical axis, the elevator including an elevator actuator; a vertical movement mechanism coupled to the elevator; a build platform including a build plate having a lower surface; and an imaging module further including: a light engine configured to project pixelated light upward; and a distance sensor; loading the build platform onto the elevator; operating the vertical movement mechanism to lower the lower surface of the build platform into a measurement range with the distance sensor; scanning the imaging module along at least one lateral axis; concurrent with scanning the distance sensor, receiving a signal from the distance sensor indicative of a plurality of vertical locations along the lateral axis of the lower surface of the build platform; computing an inclination of the lower surface of the build platform based upon the signal from the distance sensor; and operating the elevator actuator to level the lower surface of the build platform.
2. 2 . The method of claim 1 wherein the elevator includes: a lower support further including the elevator actuator extending upward from an upper side of the lower support; and an upper support with a lower side including a datum surface engaged with the elevator actuator; the method includes operating the actuator to modulate an orientation of the upper support with respect to the lower support and with respect to a horizontal axis.
3. 3 . The method of claim 2 wherein the elevator actuator includes two elevator actuators, the lower support includes a pin that extends upward from the upper side of the lower support, the two elevator actuators and the pin engage three datum surfaces on the lower side of the upper support, operating the two elevator actuators modulates the orientation of the upper support along two orthogonal horizontal axes.
4. 4 . The method of claim 1 wherein the build platform includes a support plate above and coupled to the build plate, loading the build platform includes loading the support plate onto the elevator.
5. 5 . The method of claim 4 wherein a plurality of vertical rods couple a lower surface of the support plate to an upper surface of the build plate, loading the build platform onto the elevator includes loading the lower surface of the support plate onto an upper surface of the elevator.
6. 6 . The method of claim 4 wherein the elevator includes at least one electromagnet, loading the build platform includes energizing the at least one electromagnet to magnetically hold the support plate to the elevator.
7. 7 . The method of claim 1 including scanning and operating the light engine to image a layer of photocurable resin.
8. 8 . The method of claim 1 wherein the imaging module includes a plurality of light engines, the method including scanning and operating the plurality of light engines to image a layer of photocurable resin.
9. 9 . The method of claim 1 wherein the distance sensor is a confocal sensor, the method including receiving the signal from the confocal sensor.
10. 10 . The method of claim 1 wherein the 3D printing system includes a rigid base, a vertical beam extending upward from the rigid base, and a plurality of actuators extending upward from the rigid base, the method further including: loading a build vessel onto the rigid base and engaging the plurality of actuators; scanning the imaging module along at least one lateral axis along an upper surface of a transparent plate at a lower end of the build vessel; concurrent with scanning the imaging module, receiving a signal from the distance sensor indicative of a plurality of vertical locations along the lateral axis of the lower surface of the build vessel; and operating the plurality of actuators to adjust a height of the upper surface of the transparent plate of the build vessel.
11. 11 . A method of manufacturing a three-dimensional (3D) article comprising: providing a 3D printing system including: a rigid base; a support beam extending upward from the rigid base; an elevator configured for vertical translation along the support beam, the elevator including: a lower support slidingly coupled to the support beam and having an upper surface including an elevator actuator extending upward; and an upper support with a lower surface including a datum surface engaged with the actuator; a vertical movement mechanism coupled to the elevator; a build platform including a support plate above and coupled to a build plate, the build plate having a lower surface; an imaging module further including: a light engine configured to project pixelated light upward; and a distance sensor; loading the support plate onto an upper surface of the upper support of the elevator; operating the vertical movement mechanism to lower the lower surface of the build plate into proximity with the distance sensor; scanning the imaging module along at least one lateral axis; concurrent with scanning the distance sensor, receiving a signal from the distance sensor indicative of a plurality of vertical locations along the lateral axis of the lower surface of the build platform; computing an inclination of the lower surface of the build platform based upon the signal from the distance sensor; and operating the elevator actuator to level the lower surface of the build plate.
12. 12 . The method of claim 11 wherein the lower support includes a proximal portion that is slidingly coupled to the support beam and a distal portion that extends along a first lateral axis X, the elevator actuator includes two elevator actuators located on the proximal portion of the lower support and a pin that extends upward from the distal portion of the lower support, the upper support includes datum surfaces that engage the two elevator actuators and the pin, operating the elevator actuator includes operating the two elevator actuators rocks the upper support with respect to the pin.
13. 13 . The method of claim 11 wherein the upper support includes at least one electromagnet, loading the support plate includes energizing the at least one electromagnet to magnetically hold the support plate to the elevator.
14. 14 . The method of claim 11 including scanning and operating the light engine to image a layer of photocurable resin.
15. 15 . The method of claim 1 wherein the 3D printing system includes plurality of actuators extending upward from the rigid base, the method further including: loading a build vessel onto the rigid base and engaging the plurality of actuators; scanning the imaging module along at least one lateral axis along a surface of a transparent plate at a lower end of the build vessel; concurrent with scanning the imaging module, receiving a signal from the distance sensor indicative of a plurality of vertical locations along the lateral axis of the surface of the transparent plate of the build vessel; computing an inclination of the surface of the transparent plate of the build vessel based upon the signal from the distance sensor; and operating the plurality of actuators to adjust a height of the build vessel.
16. 16 . A method of manufacturing a three-dimensional (3D) article comprising: providing a 3D printing system including: a rigid base having a plurality of base actuators; an elevator configured for translation along a vertical axis, the elevator including an elevator actuator; a vertical movement mechanism coupled to the elevator; a build platform including a build plate having a lower surface; and an imaging module further including: a light engine configured to project pixelated light upward; and a distance sensor; a build vessel having a lower end with a transparent plate; loading the build platform onto the elevator; operating the vertical movement mechanism to lower the lower surface of the build platform into proximity with the distance sensor; scanning the imaging module along at least one lateral axis; concurrent with scanning the distance sensor, receiving a signal from the distance sensor indicative of a plurality of vertical locations along the lateral axis of the lower surface of the build plate; computing an inclination of the lower surface of the build plate based upon the signal from the distance sensor; operating the elevator actuator to level the lower surface of the build plate; loading the build vessel onto the rigid base; scanning the imaging module along at least one lateral axis; concurrent with scanning the distance sensor, receiving a signal from the distance sensor indicative of a plurality of vertical locations along the lateral axis of a surface of the transparent plate of build vessel; and operating the plurality of base actuators to adjust a height and orientation of the surface of the transparent plate of the build vessel.
17. 17 . The method of claim 16 wherein the surface of the transparent plate is an upper surface of the transparent plate.
18. 18 . The method of claim 16 including scanning and operating the light engine to image a layer of photocurable resin.
19. 19 . The method of claim 16 wherein the lower surface of the build plate is leveled before adjusting the height of the surface of the transparent plate of the build vessel.
20. 20 . The method of claim 19 wherein the build platform is unloaded from the elevator before the height of the surface of the transparent plate of the build vessel is adjusted.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This non-provisional patent application claims priority to U.S. Provisional Application Ser. No. 63/484,354, Entitled “Method for Manufacturing Low Modulus Articles” by David Sabo et al., filed on Feb. 10, 2023, incorporated herein by reference under the benefit of U.S.C. 119(e). FIELD OF THE INVENTION The present disclosure concerns an apparatus and method for fabrication of solid three dimensional (3D) articles of manufacture from radiation curable materials. More particularly, the present disclosure concerns an apparatus for producing customized and extremely precision 3D articles. BACKGROUND Three dimensional (3D) printers are in rapidly increasing use for manufacturing customized articles. One class of 3D printers includes stereolithography printers having a general principle of operation including the selective curing and hardening of radiation curable (i.e., photocurable) liquid resins. One type of stereolithography system includes a containment vessel holding the curable resin, a movement mechanism coupled to a support tray, and a light engine. The stereolithography system forms a three dimensional (3D) article of manufacture by selectively curing layers of the photocurable resin onto a lower surface of the support tray. There is a desire to produce efficiently produce 3D articles having feature size tolerances that are less than 10 microns, less than five microns, or less than 2 microns in size. Various challenges to fabricating such small geometries include limitations on the optical and mechanical systems that are historically suitable for tolerances that are more in a range of 20 microns or larger. SUMMARY A first aspect of the disclosure is a method of manufacturing a three-dimensional (3D) article using a 3D printing system. The 3D printing system includes an elevator, a vertical movement mechanism, a build platform, and an imaging module. The elevator is configured for translation along a vertical axis and includes an elevator actuator. The vertical movement mechanism is coupled to the elevator. The build platform includes a build plate having a lower surface. The imaging module includes a light engine and a distance sensor. The method includes loading the build platform onto the elevator, operating the vertical movement mechanism to lower the lower surface of the build platform into a measurement range with the distance sensor, scanning the imaging module along at least one lateral axis, concurrent with scanning the distance sensor, receiving a signal from the distance sensor indicative of a plurality of vertical locations along the lateral axis of the lower surface of the build platform, computing an inclination of the lower surface of the build platform based upon the signal from the distance sensor, and operating the elevator actuator to level the lower surface of the build platform. The distance sensor can be a confocal distance sensor or a plurality of confocal distance sensors. Other distance sensors can be used such as a laser displacement sensor. The light engine can include one or a plurality of projection light engines. Operating an actuator within an elevator to level the lower surface of the build platform enables more accurate imaging of the 3D article. In fact, this method of leveling enables dimensional tolerances that are an order of magnitude smaller than conventional 3D printing systems. The implementations listed infra further enable precision imaging. In one implementation, the elevator includes (a) a lower support including the elevator actuator extending upward from an upper side of the lower support and (b) an upper support with a lower side including a datum surface engaged with the elevator actuator. The method includes operating the actuator to modulate an orientation of the upper support with respect to the lower support and with respect to a horizontal axis. In another implementation the elevator includes a lower support and an upper support. The lower support has an upper side. The upper support includes a lower side including three datum surfaces. The lower support includes a pin and two elevator actuators that extend upward from the upper side and engage the three datum surfaces. Operating the two elevator actuators modulates an orientation of the upper support along two orthogonal axes. In yet another implementation, the build platform includes a support plate having a lower surface and a plurality of vertical rods that couple the lower surface of the support plate to an upper surface of the build plate. Loading the build platform onto the elevator includes loading the lower surface of the support plate onto an upper surface of the elevator. In a further implementation, elevator includes at least one electromagnet. The build platform includes a support plate having a lower surface and a plurality of vertical rods that couple the lower surface of the support plate to an upper surface of the build plate. Loading the build