Abstract: A powder dosing system for an apparatus for manufacturing a three-dimensional object from powder, the powder dosing system comprising: a rotating agitator arranged to agitate a supply of delivered powder by rotating through an agitation volume; a recirculation edge adjacent the agitation volume, arranged to allow excess agitated powder to freely flow over the recirculation edge and out of the dosing system; and a dosing blade arranged to dose a dosed volume of powder to a work surface comprising a build bed surface; wherein the dosing blade is arranged to sweep through a swept volume, which is located, in a vertical sense, above the agitation volume and overlaps, in a vertical sense, the agitation volume, such that the dosing blade doses agitated powder to the work surface.

Abstract: A method for the manufacture of three-dimensional objects is disclosed, utilising an independently operable printing sled (350) for sintering fusible powder and an independently operable powder distribution sled (300) for depositing a layer of fusible powder on the sintered layer. Since the printing sled and the powder distribution sled are independently operable, the time between sintering and deposition can be altered, dependent on the printing conditions and materials, resulting in an enhanced bond between the layers of the three-dimensional object.

Abstract: A powder recirculation system for an apparatus for manufacturing a three-dimensional object (500) from powder is provided. The powder recirculation system comprises: a delivery path coupled to an outlet of a powder tank (410), the powder tank configured to store the powder; a powder repository (115) coupled to an outlet of the delivery path, the delivery path comprising a delivery mechanism for delivering the powder from the powder tank to the powder repository; a powder recirculation path coupled to an outlet (102) of the powder repository, wherein the powder recirculation path is configured to return first excess powder from the powder repository to the delivery path at a location (103, 104) upstream of the outlet of the powder tank.

Abstract: An agitator for an apparatus for the manufacture of three-dimensional objects. The agitator comprises at least one blade coupled to a shaft, and extending outwardly from the shaft. Cavities are defined between the at least one blade and the shaft, such that movement of the agitator within a powder repository keeps the powder in a fluidised state and prevents the powder from agglomerating.

Abstract: A printer head for a thermal printer for building a three-dimensional model by sequential deposition of a plurality of cross-sectional layers, the thermal print head being movable relative to a material bed over a deposited layer. A protective sheet might be disposed between the thermal print head and deposited layer in a thermal printer according to the invention. Temperature control of the material bed to prevent warping of the model is provided by an independently heatable cover in contact with the surface of the material bed. The thermal print head further comprises a cooling element.