Abstract: A level sensor assembly (552) for estimating a level of a dielectric powder (412) in a container assembly (544) includes a first electrode member (554) that is coupled to the container assembly (544); a second electrode member (556) that is coupled to the container assembly (544): and a control system (424). The second electrode member (556) is spaced apart from the first electrode member (554) and configured so that powder (512) in the container assembly (544) is positioned at least partly between the electrode members (554) (556). The control system (424) utilizes a capacitance between the electrode members (554) (556) to estimate the level of the powder (512) in the container assembly (544).

Abstract: Electron beam position, size, or shape can be estimated by deflecting the beam to a plurality of apertures, either continuously or step-wise. Beam portions transmitted, absorbed, or scattered can be used to assess position, size, and shape. In other examples, a beam sensing aperture and the beam are oscillated with respect to each other by moving the aperture or varying the beam deflection or both. The beam can be directed to segmented detectors such as a quad detector, and currents in the segments used to assess beam position, shape, or size. The segments can be formed from a single conductive sheet on which the segments are defined but remain attached. After the conductive sheet is secured with an insulative adhesive, portions of the conductive sheet are broken away, leaving aligned segments.

Abstract: A processing machine (10) for building an object (11) from powder (12) includes a build platform (434A); a powder supply assembly (418); and an energy system (22) that melts the powder (12) on the build platform (434A) to form the object (11). The powder supply assembly (418) can include (i) a first container region (444A) that retains the powder (12) prior to distribution onto the build platform (434A); (ii) a supply outlet (439) positioned over the build platform (434A); (iii) a flow control assembly (442) that selectively controls the flow of the powder (12) from the first container region (444A) to the supply outlet (439); (iv) a second container region (446A) that retains the powder (12) for refilling the first container region (444A); and (v) an actuator system (448) that urges powder (12) from the second container region (446A) to fill the first container region (444A).

Abstract: 3D metrology techniques are disclosed for determining a changing topography of a substrate processed in an additive manufacturing system. Techniques include fringe scanning, simultaneous fringe projections, interferometry, and x-ray imaging. The techniques can be applied to 3D printing systems to enable rapid topographical measurements of a 3D printer powder bed, or other rapidly moving, nearly continuous surface to be tested. The techniques act in parallel to the system being measured to provide information about system operation and the topography of the product being processed. A tool is provided for achieving higher precision, increasing throughput, and reducing the cost of operation through early detection and diagnosis of operating problems and printing defects. These techniques work well with any powder bed 3D printing system, providing real-time metrology of the powder bed, the most recently printed layer, or both without reducing throughput.

Abstract: To improve the operation of 3D printing systems, techniques are disclosed for a rotary 3D printer comprising: a main rotating support table rotating about a first axis and one or more secondary support tables rotating around a non-coaxial secondary axis; a powder supply assembly for distributing powder onto the tables; and an energy system for directing an energy beam at the powder to form a part. The main support table and secondary support tables can rotate in the same or opposite directions. Disclosed techniques include: grooved support table surfaces for improving stability of applied powder; reciprocating bellows for controlling a differential load on actuators that move the support tables; high temperature bearings or bushings for supporting rotary motion at high temperatures; and a mechanism for counterbalancing a weight of the part being built.

Abstract: A processing machine (10) for building a part (11) includes: a support device (26) including a support surface (26B); a drive device (28) which moves the support device (26) so as a specific position on the support surface (26B) is moved along a moving direction (25); a powder supply device (18) which supplies a powder (12) to the moving support device (26) to form a powder layer (13); an irradiation device (22) which irradiates at least a portion of the powder layer (13) with an energy beam (22D) to form at least a portion of the part (11) from the powder layer (13) during a first period of time; and a measurement device (20) which measures at least portion of the part (11) during a second period of time. The first period in which the irradiation device (22) irradiates the powder layer (13) with the energy beam (22D) and the second period in which the measurement device (22) measures are overlapped.