Abstract: A structure for delivering a flow of gas across a window or aperture of an imaging or measurement device within an apparatus for the manufacture of three-dimensional objects by layer-by-layer consolidation of particulate matter, the structure comprising: a hollow body having an upper aperture for mounting in correspondence with the window/aperture of said device, a gas flow intake region below the upper aperture, and a lower aperture; wherein the gas flow intake region is provided on opposing sides of the hollow body when viewed in cross-section along a longitudinal axis that runs from the upper aperture to the lower aperture, and comprises one or more channels configured to allow, in use, a flow of intake gas to enter the hollow body from the opposing sides of the hollow body with a flow component that predominantly lies in a plane parallel to the plane of the upper aperture, and to come into confluence within the hollow body; and wherein the hollow body is symmetrically shaped about the longitudinal axis so

Abstract: An apparatus for the layer-by-layer formation of three-dimensional objects, the apparatus comprising a gas extraction system and an enclosed working space from which gas is to be extracted, wherein the working space is enclosed by side walls, a ceiling and a working surface, and comprises a working space inlet for allowing gas to enter into the working space, a working space outlet for allowing gas to exit the working space, and a build bed surface in which a layer of the object is formed; wherein the gas extraction system comprises: a primary conduit comprising at least a first primary inlet, at least a first interfacing inlet, and a primary outlet; and at least a first secondary conduit comprising a respective first secondary inlet and a respective first secondary outlet, the first secondary inlet being in fluidic communication with the working space for extracting gas from the working space, and the first secondary outlet being in fluidic communication with the first interfacing inlet; wherein the or each

Abstract: A method of operating an apparatus for the layerwise manufacture of 3D objects. The method includes two or more operational cycles of a warm up phase, starting from ambient, followed by a build phase and a cooling phase. The warm up phase and the build phase each include a layer cycle of: (a) dosing build material to the work surface; (b) distributing a portion of the dosed amount over a build area; (c) heating the dosed amount; and (d) monitoring a temperature of the build material to determine a thermal state. The build phase includes melting layer-specific regions. These steps are repeated until the warm up and build phases are completed. A property of the subsequent warm up phases is determined such that the duration of a subsequent warm up phase is shorter than the duration of a preceding warm up phase.

Abstract: An additive manufacturing apparatus for 3D object formation includes a process chamber, a gas extraction duct and a controller. The gas extraction duct main and secondary ducts. The main duct has an extraction opening connectable to an extraction source and an inflow opening drawing in gas from an external environment. The secondary duct has an inlet opening connected to a process chamber outlet and an outlet opening coupled to the main duct. One or more temperature sensors is thermally coupled to the gas flow temperature within the interior of the gas extraction duct. The temperature sensors include an extraction temperature sensor and/or an inflow temperature sensor. A heater is arranged to provide a baseline temperature to the inflow temperature sensor. The controller determines, based on the temperature measurements, whether a gas flow rate applied by the extraction source is within a predefined range.

Abstract: A stirring device for a powder tank of an apparatus for manufacturing a three-dimensional object. The stirring device is configured to rotate within the powder tank about an axis of rotation, and comprises a base plate and a strut. The strut extends from the base plate and is arranged to extend into the powder tank forming an obtuse angle with the outer edge of the base plate.

Abstract: A method of operating an apparatus for the layerwise manufacture of 3D objects. The method includes two or more operational cycles of a warm up phase, starting from ambient, followed by a build phase and a cooling phase. The warm up phase and the build phase each include a layer cycle of: (a) dosing build material to the work surface; (b) distributing a portion of the dosed amount over a build area; (c) heating the dosed amount; and (d) monitoring a temperature of the build material to determine a thermal state. The build phase includes melting layer-specific regions. These steps are repeated until the warm up and build phases are completed. A property of the subsequent warm up phases is determined such that the duration of a subsequent warm up phase is shorter than the duration of a preceding warm up phase.

Abstract: A method for recirculating powder in an apparatus for manufacturing a three-dimensional object from the powder. The powder recirculation method includes: providing powder in a powder repository, the powder being one of fresh powder, excess powder or a blend thereof; transferring the powder from the repository to a work surface; distributing the powder across a build surface and resulting in a portion of the powder defining excess powder; returning the excess powder back to the repository; monitoring the amount of powder in the repository relative to a predetermined amount of powder; and delivering fresh powder from a powder tank to the repository when the amount of powder in the repository is less than the predetermined amount and not delivering fresh powder when excess powder is being returned to repository and the amount of powder in the repository is greater than the predetermined amount of powder.

Abstract: An apparatus for manufacturing a three-dimensional object from particulate material.

Abstract: An apparatus for formation of three-dimensional objects and having an infrared radiation deflector. The radiation deflector includes opposing first and second elongate side walls; at least one end support connecting the side walls; an upper opening and a lower opening arranged to pass lamp radiation to an exterior of the radiation deflector; and a mounting point provided at the/each end support for mounting an infrared lamp. The side walls include first and second elongate mirrors extending parallel to a lamp axis and along a lower internal portion of the respective side walls. The lamp axis extends along and between the first and second mirrors, each of which has a concave surface with respect to the lamp axis. The first mirror is an upward deflecting mirror and is arranged for redirecting at least a portion of direct lamp radiation through the upper opening.

Abstract: An apparatus for the layer-by-layer formation of three-dimensional objects. The apparatus includes a gas extraction system and an enclosed working space. The working space includes a working space inlet allowing gas to enter, a working space outlet allowing gas to exit, and a build bed surface in which a the object is formed. The gas extraction system includes: a primary conduit having a first primary inlet, a first interfacing inlet, and a primary outlet connectable to an external extraction source; and a first secondary conduit having a first secondary inlet and outlet. The first secondary inlet is in fluidic communication with the working space. The first secondary outlet is in fluidic communication with the first interfacing inlet. The gas extraction system further includes a flow controller to control the flow of gas from the working space into the first secondary conduit, and thereafter into the primary outlet.

Abstract: An apparatus for manufacturing a three-dimensional object from particulate material.

Abstract: An infrared lamp assembly for an apparatus for the formation of three-dimensional objects by consolidation of particulate material, the assembly comprising: an elongate infrared lamp extending along a lamp axis, an elongate shield extending parallel to and along one side of the axis of the lamp, and a support structure holding at least one of the ends of the lamp and of the shield, wherein the elongate shield at least partially bounds the space to one side of the lamp, and wherein the assembly provides a lower opening below the lamp and an upper opening above the lamp, such that, in use, radiation generated by the lamp is able to radiate through the openings and away from the lamp in directions not bounded by the shield.

Abstract: A method of manufacturing a three-dimensional object from a powder to form each layer of the object. The method includes the steps of driving a powder distribution sled in a first direction to distribute a layer of powder; driving a print sled in the first direction; driving the print sled and the powder distribution sled in a second direction; preheating the layer of powder by activating multiple radiation sources during various ones of the driving steps; during some of the driving steps, depositing a pattern of fluid onto the layer of powder; and sintering the powder on which fluid was deposited only in the second direction, by activating the at least one radiation source assembly during various ones of the driving steps in that direction. Repeating the above steps to distribute the next layer of powder.

Abstract: An apparatus (1) for manufacturing a three-dimensional object from particulate material, the apparatus comprising: • a work space (100) bounded by a first side wall (100A) on a first side of the work space, and a second side wall (100B) on a second side of the work space, the first side wall opposing the second side wall; • a build bed (170) having a build bed surface (160), the build bed surface being comprised in the floor of the work space and having a first edge (160?) on the first side of the work space, towards the first side wall, and a second edge (160?) on the second side of the work space, towards the second side wall; • a first gas inlet (101A) at or near the first side wall; • a second gas inlet (101B) at or near the second side wall; • a first gas outlet (102A) above the floor (100C) of the work space, the position of the first gas outlet being coincident with the first edge of the build bed surface, or between the first edge of the build bed surface and the first gas inlet; and • a second gas ou

Abstract: A controller and method for layer-by-layer manufacturing of a three-dimensional object from a powder. The method includes, in a first direction across a build area: moving a droplet deposition unit and depositing a radiation absorber onto regions of a previously applied layer of powder; moving a first radiation source according to a first velocity profile whilst activating the first radiation source to fuse the regions of powder where the absorber has been deposited; moving a powder distributor according to a second velocity profile and distributing a fresh layer of powder; and moving a second radiation source whilst activating the second radiation source to preheat the fresh layer of powder. The method further includes adjusting the first and/or second velocity profiles to control a time interval between the passing of the first radiation source and the powder distributor.

Abstract: A method of operating an apparatus for the layerwise manufacture of 3D objects. The method includes a warm up phase followed by a build phase. The phases each include a cycle of (a) dosing an amount of build material from a dosing device; (b) pushing a portion of the dosed amount across a build area into a receiving chamber; (c) heating the dosed amount at one or both of (a) and (b); repeating (a) to (c) until each phase is complete. During the build phase, at step (b) a layer is formed over the build area and, at step (c), build material within a layer-specific region is selectively melted. Over a given duration of time, an aggregate volume of build material pushed into the receiving chamber during the warm up phase is larger than an aggregate volume of build material pushed into the receiving chamber during the build phase.

Abstract: A method of operating an apparatus for the layerwise manufacture of 3D objects. The method includes two or more operational cycles of a warm up phase, starting from ambient, followed by a build phase and a cooling phase. The warm up phase and the build phase each include a layer cycle of: (a) dosing build material to the work surface; (b) distributing a portion of the dosed amount over a build area; (c) heating the dosed amount; and (d) monitoring a temperature of the build material to determine a thermal state. The build phase includes melting layer-specific regions. These steps are repeated until the warm up and build phases are completed. A property of the subsequent warm up phases is determined such that the duration of a subsequent warm up phase is shorter than the duration of a preceding warm up phase.

Abstract: An apparatus for formation of three-dimensional objects and having an infrared radiation deflector. The radiation deflector includes opposing first and second elongate side walls; at least one end support connecting the side walls; an upper opening and a lower opening arranged to pass lamp radiation to an exterior of the radiation deflector; and a mounting point provided at the/each end support for mounting an infrared lamp. The side walls include first and second elongate mirrors extending parallel to a lamp axis and along a lower internal portion of the respective side walls. The lamp axis extends along and between the first and second mirrors, each of which has a concave surface with respect to the lamp axis. The first mirror is an upward deflecting mirror and is arranged for redirecting at least a portion of direct lamp radiation through the upper opening.

Abstract: A method for recirculating powder in an apparatus for manufacturing a three-dimensional object from the powder. The powder recirculation method includes: providing powder in a powder repository, the powder being one of fresh powder, excess powder or a blend thereof; transferring the powder from the repository to a work surface; distributing the powder across a build surface and resulting in a portion of the powder defining excess powder; returning the excess powder back to the repository; monitoring the amount of powder in the repository relative to a predetermined amount of powder; and delivering fresh powder from a powder tank to the repository when the amount of powder in the repository is less than the predetermined amount and not delivering fresh powder when excess powder is being returned to repository and the amount of powder in the repository is greater than the predetermined amount of powder.

Abstract: An infrared radiation deflector (100) for an elongate infrared lamp (110), the radiation deflector (100) comprising opposing first and second elongate side walls (130_1, 130_2); at least one end support (170) connecting the ends of the side walls (130_1, 130_2); an upper opening (140) and a lower opening (150) arranged to pass lamp radiation to an exterior of the radiation deflector (100); and a mounting point (172) provided at the/each end support (170) for mounting the infrared lamp (110) and defining between them a lamp axis location (114); wherein the first and second elongate side walls (130_1, 130_2) comprise a first elongate mirror (130_1) and a second elongate mirror (130_2) extending parallel to the lamp axis location (114) and along at least a lower internal portion of the respective first and second side walls (130_1, 130_2); wherein the lamp axis location (114) extends along and between the first mirror (130_1) and the second mirror (130_2), the first and second mirror (130_1, 130_2) each having a