MULTIPLE POWDER DELIVERY FOR SELECTIVE LASER SINTERING.

摘要

An apparatus and method for producing parts by fusing selected portions of a layer of powder at a target area, including the systems for delivering the powder to the target area, is disclosed. Multiple powder pistons are included in the apparatus, each of which lift a volume of powder above a surface in an alternating manner relative to one another. Powder delivery begins by the lifting of a volume of powder at a first location on one side of the target area. A counter-rotating roller moves across the lifted powder, distributes it over the target area, and rests beyond a second powder lifting location on the other side of the target area. Portions of the powder layer are then fused at the target area according to a cross-section of the part to be produced, and is followed by lowering a part cylinder at the target area in order to accept the next layer of powder. A second volume of powder is lifted at the second location, and the counter-rotating roller moves across the second location and the target area to deliver the next layer of powder to the target area. The multiple powder piston system reduces the excess powder in the chamber, speeds the delivery of powder, and facilitates the installation of powder during the process.