Additive manufacturing apparatus and method for large components

1. An additive manufacturing method, comprising:

positioning one or more build units over a build chamber defined in an annular space between a ring-shaped inner side wall and a ring-shaped outer side wall, each of the one or more build units being housed in a housing, the build chamber having a moveable build platform disposed therein between the inner and outer side walls;

moving the build chamber to define a spiral movement by rotating the build chamber about an axis while simultaneously translating the build platform along the axis;

while moving the build chamber:

maintaining the housing in sealing engagement with the inner and outer walls;

using the one or more build units to deposit powder into the build chamber;

using the one or more build units to direct a beam from a directed energy source to fuse the powder; and

continuing the steps of depositing, directing, and moving to build up a part in a spiral configuration until the part is complete.

2. The method according to claim 1 , wherein the one or more build units include an applicator configured to scrape powder deposited into the build chamber.

3. The method according to claim 2 , further including the step of positioning the applicator at a position relative to the build platform that is less than a selected layer increment.

4. The method according to claim 3 , further including the step of maintaining the position of the applicator as the build platform translates along the axis.

5. The method according to claim 4 , further including the step of using two or more build units to fuse multiple overlapping layers in the spiral configuration as the build platform translates along the axis.

6. The method according to claim 1 , wherein the one or more build units include a powder dispenser, an applicator, and a directed energy source.

7. The method according to claim 1 , wherein first and second spaced-apart build units contained in a single housing are positioned over the build chamber, each of the first and second spaced-apart build units includes a directed energy source, wherein the first build unit builds a first section of a part and the second build unit builds a second section of the part.

8. The method according to claim 1 , further comprising the step of evacuating the build chamber of loose powder when the part is complete.

9. An additive manufacturing method, comprising:

providing an apparatus having:

a ring-shaped inner side wall and a ring-shaped outer side wall defining a build chamber therebetween;

one or more housings for movement along the inner and outer side walls, each of the housings including:

two or more spaced-apart build units, each build unit having a directed energy source configured to fuse powder contained in the build chamber; and

a moveable build platform disposed between the inner and outer side walls;

moving the build chamber to define a spiral movement by rotating the build chamber about an axis while simultaneously translating the build platform along the axis, wherein while moving the build chamber maintaining the housing in sealing engagement with the inner and outer side walls;

using a first one of the two or more build units to build a base section of the part; and

after the base section of the part has been completed, using the two or more build units simultaneously, wherein each of the two or more build units is used to build a separate wall section extending from the base.

10. The method according to claim 9 , wherein the apparatus is configured to use each of the two or more spaced-apart build units to build two or more sections of a part at the same time.

11. The method according to claim 9 , further including an actuator assembly connected to the build platform, the actuator assembly being configured to rotate and move the build platform continuously along a build axis to provide a spiral movement and permit a part to be built continuously in a spiral configuration.