METHODS AND APPARATUS FOR PROCESSING AND DISPENSING MATERIAL DURING ADDITIVE MANUFACTURING

• US 20190322044A1
• Filed: 06/28/2019
• Published: 10/24/2019
• Est. Priority Date: 08/31/2016
• Status: Active Grant

• Current Assignee: Thermwood Corporation
• Original Assignee: Thermwood Corporation
• Inventors: SUSNJARA, Kenneth J., VOTE, Nicolas, GAESSER, Robert, SMIDDY, Brian S., VAAL, Scott G.
• Granted Patent: US 10,688,719 B2
• Time in Patent Office: Days
• CPC Class Codes: B29C 64/118 using filamentary material being melted, e.g. fused deposition modelling [FDM]
• CPC Class Codes: B29C 64/209 Heads; Nozzles
• CPC Class Codes: B29C 64/379 Handling of additively manufactured objects, e.g. using robots
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• 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 system for additive manufacturing includes a nozzle configured to translate along a first axis, a second axis perpendicular to the first axis, and a third axis orthogonal to the first and second axes, wherein the nozzle is operably coupled to: an extruder having an outlet and including a screw disposed within a barrel, and a pump having an inlet and an outlet. The inlet is coupled to the extruder, and the outlet is in fluid communication with the nozzle. The system also includes a controller configured to adjust a speed of the pump with respect to a speed of the screw to apply a target pressure at the outlet of the extruder.

Claims

1. A system for additive manufacturing, comprising:

a nozzle configured to translate along a first axis, a second axis perpendicular to the first axis, and a third axis orthogonal to the first and second axes, wherein the nozzle is operably coupled to;

an extruder having an outlet and including a screw disposed within a barrel; and

a pump having an inlet and an outlet, the inlet being coupled to the extruder, and the outlet being in fluid communication with the nozzle; and

a controller configured to adjust a speed of the pump with respect to a speed of the screw to apply a target pressure at the outlet of the extruder.

2. The system of claim 1, further including a pressure sensor configured to sense a pressure of the inlet of the pump and a pressure of an outlet of the extruder, the speed of the pump with respect to the speed of the screw being adjusted based on the pressure sensed by the pressure sensor.

3. The system of claim 1, wherein the pump is connected to the extruder without a breaker plate or a screen disposed between the pump and the extruder.

4. The system of claim 1, wherein the outlet of the extruder and the inlet of the gear pump are provided at a same location.

5. The system of claim 1, wherein the controller is configured to change the target pressure from a first target pressure to a second target pressure.

6. The system of claim 5, wherein the change to the second target pressure is performed based on a change of the flowable material.

7. The system of claim 6, wherein the change in pressure to the second target pressure is performed based on pressure feedback received by a pressure sensor.

8. The system of claim 6, wherein the first target pressure is a pressure target associated with a first flowable material and the second pressure target is a pressure target associated with a second flowable material, wherein the change to the second target pressure is performed based on a determination by the controller that an extruded material has changed from the first flowable material to the second flowable material.

9. A system for additive manufacturing, comprising:

a nozzle configured to translate along a first axis, a second axis perpendicular to the first axis, and a third axis orthogonal to the first and second axes, wherein the nozzle is operably coupled to;

an extruder including a screw disposed within a barrel; and

a pump having an inlet and an outlet, wherein the inlet is coupled to the extruder, and the outlet is in fluid communication with the nozzle; and

a controller configured to modify a size of a bead extruded by the nozzle to maintain an approximately constant sized overlap between a plurality of adjacent beads.

10. The system of claim 9, wherein the controller is configured to modify the size of the extruded bead by modifying a ratio of a translation speed of the nozzle to a speed of rotation of the pump.

11. The system of claim 10, wherein the ratio is changed based on a program stored in the controller.

12. The system of claim 10, further including a control switch, wherein the ratio is changed based on an operation of the control switch.

13. The system of claim 10, further including a control switch, wherein the ratio is changed based on an operation of the control switch and based on a program stored in the controller.

14. The system of claim 13, wherein the controller is configured to change the ratio to a first value based on the program stored in the controller, the controller configured to further change the ratio to a second value based on the operation of the control switch.

15. The system of claim 12, wherein the controller is configured to increase and decrease a speed of the gear pump based on the operation of the control switch.

16. The system of claim 9, wherein the controller is configured to change a size of a bead with respect to two adjacent beads.

17. An additive manufacturing method for delivering a flowable material from a nozzle of a programmable computer numeric control machine (CNC), the method comprising:

actuating an extruder to form a flowable material;

delivering the flowable material to a pump;

operating the pump at a speed; and

adjusting at least one of the speed of the pump or a rate of translation of the nozzle based on a size of a boundary area formed by at least one adjacent bead of flowable material.

18. The method of claim 17, wherein the adjusting includes adjusting the at least one of the speed of the pump or the rate of translation of the nozzle for a plurality of adjacent beads of flowable material.

19. The method of claim 18, wherein the size of the bead is adjusted based on a determination that a standard bead size will result in the formation of a void within the boundary.

20. The method of claim 17, further including modifying a size of an extruded bead with respect to two extruded beads disposed adjacent to the extruded bead having the modified size.