Additive manufacturing recoat assemblies including sensors and methods for using the same

Patent metadata

Field	Value
Publication number	US-12059841-B2
Application number	US-202017611259-A
Country	US
Kind code	B2
Filing date	May 22, 2020
Priority date	May 23, 2019
Publication date	Aug 13, 2024
Grant date	Aug 13, 2024

Abstract

A recoat assembly for an additive manufacturing system includes a first roller support, a second roller support, a first roller disposed between and supported by the first roller support and the second roller support, a first rotational actuator operably coupled to the first roller and configured to rotate the first roller about a first rotation axis, and a first sensor mechanically coupled to and in contact with the first roller support, where the first sensor outputs a first output signal indicative of a first force incident upon the first roller.

First claim

The invention claimed is:

1. A recoat assembly for an additive manufacturing system, the recoat assembly comprising:
a first roller support;
a second roller support;
a first roller disposed between and supported by the first roller support and the second roller support;
a first rotational actuator operably coupled to the first roller and configured to rotate the first roller about a first rotation axis;
a first sensor mechanically coupled to and in contact with the first roller support, wherein the first sensor outputs a first output signal indicative of a first force incident upon the first roller; and
an electronic control unit communicatively coupled to the first rotational actuator,
wherein the electronic control unit is configured to direct the first rotational actuator to adjust the rotation of the first roller based on a comparison of an expected first output signal to the first output signal.

2. The recoat assembly of claim 1 , wherein the first sensor is a strain gauge mechanically coupled to the first roller support, and wherein the strain gauge is oriented in order to measure a strain in at least one of a vertical direction transverse to the first rotation axis of the first roller or a horizontal direction transverse to the first rotation axis of the first roller.

3. The recoat assembly of claim 1 , wherein the first sensor is a load cell mechanically coupled to the first roller support and configured to measure a force in a vertical direction transverse to the first rotation axis of the first roller.

4. The recoat assembly of claim 1 , wherein the first roller support includes a flexure to which the first sensor is coupled.

5. The recoat assembly of claim 1 , further comprising a second sensor mechanically coupled to and in contact with the second roller support.

6. The recoat assembly of claim 1 , further comprising:
a third roller support;
a fourth roller support;
a second roller disposed between and supported by the third roller support and the fourth roller support;
a second rotational actuator operably coupled to the second roller and configured to rotate the second roller about a second rotation axis, the second rotation axis being parallel to the first rotation axis; and
a third sensor mechanically coupled to and in contact with the third roller support, wherein the third sensor outputs a third output signal indicative of a second force incident upon the second roller.

7. An additive manufacturing system comprising:
a recoat assembly comprising:
a first roller support;
a second roller support;
a first roller disposed between and supported by the first roller support and the second roller support;
a first rotational actuator operably coupled to the first roller and configured to rotate the first roller about a first rotation axis;
a first sensor mechanically coupled to and in contact with the first roller support, wherein the first sensor outputs a first output signal indicative of a first force incident upon the first roller; and

an electronic control unit configured to:
receive the first output signal of the first sensor;
determine a first force on the first roller based on the first output signal of the first sensor; and
adjust at least one operating parameter of the additive manufacturing system based on a comparison of an expected force on the first roller to the first force on the first roller determined based on the first output signal of the first sensor.

8. The additive manufacturing system of claim 7 , further comprising:
a build area;
a transverse actuator operably coupled to the recoat assembly and operable to move the recoat assembly relative to the build area to spread a build material on the build area; and

a current sensor configured to sense a current driving the transverse actuator, wherein the electronic control unit is configured to adjust the at least one operating parameter of the additive manufacturing system based on the sensed current.

9. The additive manufacturing system of claim 8 , wherein the at least one parameter of the additive manufacturing system comprises a speed with which the transverse actuator moves the recoat assembly relative to the build area.

10. The additive manufacturing system of claim 7 , further comprising:
a build area; and
a vertical actuator for moving the first roller in a vertical direction transverse to the rotation axis of the first roller, wherein the at least one parameter of the additive manufacturing system comprises a height of the first roller relative to the build area set by the vertical actuator.

11. The additive manufacturing system of claim 7 , further comprising:
a build area;

a print head for depositing binder material; and
a print head actuator operably coupled to the print head and operable to move the print head relative to the build area to deposit binder material on the build area, wherein the at least one parameter of the additive manufacturing system comprises a speed with which the print head actuator moves the print head relative to the build area.

12. A method of adjusting at least one operating parameter of an additive manufacturing system, the method comprising:
distributing a layer of a build material on a build area with a recoat assembly, the recoat assembly comprising a first roller disposed between and supported by a first roller support and a second roller support, a first rotational actuator operably coupled to the first roller and configured to rotate the first roller about a first rotation axis, and a first sensor mechanically coupled to and in contact with the first roller support;
receiving a first output signal from the first sensor as the layer of the build material is distributed on the build area with the recoat assembly;
determining a first force on the first roller based on the first output signal of the first sensor; and
adjusting the at least one operating parameter of the additive manufacturing system based on a comparison of an expected force on the first roller to the first force on the first roller determined based on the first output signal of the first sensor.

13. The method of claim 12 , wherein the at least one operating parameter of the additive manufacturing system comprises one or more of: (i) a speed with which a transverse actuator moves the recoat assembly relative to the build area; (ii) a speed of rotation of the first rotational actuator; (iii) a target thickness of a subsequent layer of the build material; and (iv) a height of the first roller relative to the build area.

14. The method of claim 12 , further comprising:
determining a type of defect based on the comparison of the expected force on the first roller to the first force on the first roller determined based on the first output signal of the first sensor; and
adjusting the at least one operating parameter of the additive manufacturing system based on the type of defect.

15. The method of claim 12 , wherein adjusting the at least one operating parameter of the additive manufacturing system in response to the determined first force comprises one or more of: (i) adjusting the at least one operating parameter of the additive manufacturing system while the layer is being distributed by the recoat assembly; and (ii) adjusting the at least one operating parameter of the additive manufacturing system when a next layer is distributed by the recoat assembly.

16. The method of claim 12 , further comprising determining a wear parameter of the first roller based on the determined first force.

17. The method of claim 12 , wherein the re

Assignees

• Gen Electric

Inventors

• Bromberg Vadim
• Bonilla Carlos H
• Sterle John

Classifications

• B29C64/218 Primary

  Rollers · CPC title

• B29C64/241

  for rotary motion · CPC title

• B29C64/236

  for motion in a direction within the plane of a layer · CPC title

• B29C64/393

  for controlling or regulating additive manufacturing processes · CPC title

• B29C64/209

  Heads; Nozzles · CPC title