Patent ID: 11938539
Assignee: GENERAL ELECTRIC COMPANY
Field: Other special machines (Mechanical engineering)
Classification: CPC B  Y | IPC B

Claim 17:
18. A method of additively manufacturing a three-dimensional object, the method comprising:
irradiating a region of a powder bed with a build unit situated above the region of the powder bed, the build unit comprising an energy beam system and an inertization system, the energy beam system comprising one or more irradiation devices respectively configured to direct one or more energy beams onto a region of a powder bed, and the inertization system comprising an irradiation chamber defining an irradiation plenum and a return manifold configured to receive and/or evacuate a process gas from the irradiation plenum; and
evacuating the process gas from the irradiation plenum through the return manifold while irradiating the powder bed, wherein the return manifold comprises a plurality of return manifold bodies arranged along a width of the return manifold, each of the plurality of return manifold bodies defining a respective one of a plurality of return manifold outlets of the return manifold, the plurality of return manifold bodies respectively coupled to one another or defining a respective integrally formed portion of the return manifold, the return manifold comprising a return manifold inlet disposed at a bottom portion of the irradiation chamber and defined at least in part by each of the plurality of return manifold bodies, respective ones of the plurality of return manifold bodies comprising one or more return manifold pathways downstream of the return manifold inlet fluidly connecting the return manifold inlet to respective ones of the plurality of return manifold outlets and a process gas evacuation line, the return manifold inlet having an elongate cross-sectional profile, and the return manifold inlet fluidly communicating with the irradiation plenum defined by the irradiation chamber and the one or more return manifold pathways defined by the respective ones of the plurality of return manifold bodies;
wherein evacuating the process gas from the irradiation plenum comprises accelerating the process gas flowing into the return manifold inlet and/or through the one or more return manifold pathways by way of a pressure reduction within the return manifold inlet and/or within the one or more return manifold pathways, the pressure reduction provided by one or more narrowing regions and/or one or more rib elements disposed about the return manifold inlet and/or within the one or more return manifold pathways.