Powder layer former with flowing gas seal

Patent metadata

Field	Value
Publication number	US-11845127-B2
Application number	US-201817043112-A
Country	US
Kind code	B2
Filing date	Jun 8, 2018
Priority date	Jun 8, 2018
Publication date	Dec 19, 2023
Grant date	Dec 19, 2023

Abstract

A system to apply uniform layers of metal powder, the system includes: a conductive roller with a dielectric coating, the conductive roller biased at a first voltage; a powder supply to contain a metal powder biased at a second voltage, the powder supply to provide the metal powder to the conductive roller to form a uniform layer of metal powder on the dielectric coating of the conductive roller; a deposition area to receive the uniform layer of metal powder from the conductive roller, the deposition area biased at a third voltage, wherein the metal powder is transferred across an air gap from the conductive roller to the deposition area by electrostatic attraction of the metal powder.

First claim

What is claimed is:

1. A system to apply uniform layers of metal powder, the system comprising:
a conductive roller with a dielectric coating, the conductive roller biased at a first voltage;
a powder supply to contain a metal powder biased at a second voltage, the powder supply to provide the metal powder to the conductive roller to form a uniform layer of metal powder on the dielectric coating of the conductive roller;
a deposition area to receive the uniform layer of metal powder from the conductive roller, the deposition area biased at a third voltage and including a plurality of layers of particles stacked on each other; and
a first seal that prevents leakage of the metal powder, the first seal formed by flowing gas through a gap between the powder supply and the dielectric coating of the conductive roller,
wherein the metal powder is transferred across an air gap from the conductive roller to the deposition area by electrostatic attraction of the metal powder, and further wherein the conductive roller translates relative to the deposition area at various speeds based on a thickness of each layer of the plurality of layers of particles.

2. A system of claim 1 , wherein the conductive roller translates relative to the deposition area such that a tangential speed of the roller and the translation speed are equivalent.

3. The system of claim 1 , wherein the dielectric coating on the conductive roller comprises a material selected from the group consisting of: aluminum oxide, silicon oxide, zirconium oxide, magnesium oxide, tantalum oxide, titanium oxide, yttrium oxide silicon nitride, aluminum nitride, and mixtures thereof.

4. The system of claim 1 , wherein the dielectric coating on the conductive roller has a dielectric thickness between 0.001 and 0.5 mm.

5. The system of claim 1 , wherein the electrode and a surface of the deposition area are separated by 0.1 to 3 mm of air gap.

6. The system of claim 1 , where a voltage difference between the first voltage and the third voltage is between 100 and 5000 volts.

7. The system of claim 1 , wherein the attractive force between a particle adhered to the surface of the roller and the roller is less than the attractive force between the particle and the deposition area.

8. The system of claim 1 , wherein the powder has a median particle diameter of less than 10 microns.

9. The system of claim 1 , wherein the flowing gas is utilized to fluidize the metal powder as the metal powder interacts with the conductive roller.

10. A system to apply uniform layers of metal powder, the system comprising:
a conductive roller with a dielectric coating, the conductive roller biased at a first voltage;
a powder supply to contain a metal powder biased at a second voltage, the powder supply to provide the metal powder to the conductive roller to form a monolayer of metal powder on the roller;
a deposition area to receive the monolayer of metal powder from the conductive roller, the deposition area biased at a third voltage and including a plurality of layers of particles stacked on each other; and
a first seal that prevents leakage of the metal powder, the first seal formed by flowing gas through a gap between the powder supply and the dielectric coating of the conductive roller,
wherein the metal powder is transferred across an air gap from the roller to the deposition area by electrostatic attraction of the metal powder, and further wherein the conductive roller translates relative to the deposition area at various speeds to produce various thicknesses in the plurality of layers of particles stacked on each other.

11. The system of claim 10 , wherein the air gap is from 0.2 to 2 mm and the voltage difference is between 500 and 1500 volts.

12. A method of applying uniform layers of metal powder to a substrate comprising:
biasing a conductive core of a roller to a first voltage;
attracting the metal powder from a reservoir at a second voltage to a dielectric surface of the roller to form a uniform layer of charged metal powder particles on the dielectric surface of the roller;
transferring the metal powder from the dielectric surface of the roller to a deposition area, wherein the metal powder transfers through an air gap based on electrostatic attraction of the charged metal powder to form a uniform layer on the deposition area, the deposition area having a third voltage and including a plurality of layers of particles stacked on each other;
forming a first seal that prevents leakage of the metal powder, the first seal formed by flowing gas through a gap between the powder supply and the dielectric coating of the conductive roller; and
translating the conductive roller relative to the deposition area at various speeds to produce various thicknesses in the plurality of layers of particles stacked on each other.

13. The method of claim 12 , further comprising patterning the uniform layer of metal powder transferred to the deposition area.

14. The method of claim 12 , wherein the metal powder transferred to the deposition area has a smaller average particle size than a primary build powder in the deposition area.

15. The method of claim 12 , further comprising utilizing a first seal formed by flowing gas through a gap between the reservoir and the dielectric surface of the roller, the gas fluidizing the metal powder as the metal powder interacts with the conductive roller.

Assignees

• Hewlett Packard Development Co

Inventors

• Anthony Thomas
• Chang Seongsik
• Moore Keith Edward

Classifications

• B22F10/00 Primary

  Additive manufacturing of workpieces or articles from metallic powder (apparatus or devices therefor B22F12/00) · CPC title

• B22F10/20

  Direct sintering or melting · CPC title

• B22F12/50

  Means for feeding of material, e.g. heads · CPC title

• B22F12/63

  Rollers · CPC title

• B33Y30/00 Primary

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title