Abstract: According to one example, there is provided a method of controlling a three-dimensional printing system, comprising obtaining data relating to a three-dimensional object to be generated, controlling a set of process modules to move around a path in a single direction over a build chamber to selectively perform a respective process action on the build platform to generate a three-dimensional object therein.

Abstract: There is disclosed additive manufacturing apparatus (10), (22), (34) comprising: a heater (18), (36) to direct radiant heat onto an irradiation region (20) of a build platform (12), at least part of the heater (18), (36) being moveable to cause the irradiation region (20) to traverse over the build platform (12); a coating module (14) moveable relative the heater (18), (36) to traverse the build platform (12) to apply a build material onto the build platform (12); and a print module (16) moveable relative the heater (18), (36) to traverse the build platform (12) to selectively eject a print agent onto the build material.

Abstract: In example implementations, an apparatus includes a storage unit, an auger screw, a housing enclosing the auger screw and at least one heater coupled to the housing. The auger screw receives a build material from the storage unit and delivers the build material to a build platform via movement of the auger screw. The build material is heated by the at least one heater as the build material is being moved by the auger screw.

Abstract: In an example, a method includes acquiring a thermal image of a reflector within an additive manufacturing apparatus through a screen. An energy profile of the thermal image of the reflector may be determined and, based on the energy profile, an operational characteristic of the screen may be determined.

Abstract: In an example, an air filtration apparatus includes a cyclonic particle separation chamber having a first inlet to draw air from a first region, second inlet to draw air from a second region, and an exhaust port. The air filtration apparatus may further include a pressure sensor to sense a pressure of the first region, and a cyclonic air flow controller. The cyclonic air flow controller may control an air inflow received via the second inlet in response to an output from the pressure sensor to maintain a total air flow rate via the exhaust port.

Abstract: In example implementations, an apparatus includes a storage unit, an auger screw, a housing enclosing the auger screw and at least one heater coupled to the housing. The augers screw receives a build material from the storage unit and delivers the build material to a build platform via movement of the auger screw. The build material is heated by the at least one heater as the build material is being moved by the auger screw.

Abstract: Mechanisms to spread build material on a print bed are disclosed. In example apparatuses a conveyor, having an endless belt, is used. A build material reservoir deposits build material on the endless belt, in a build material receiving area of the conveyor. A build material preheater is used to preheat build material transported by the endless belt in a build material preheating area of the conveyor. The preheated build material is then deposited on the print bed.

Abstract: A printing system to hold printing material comprises a sealing interface to seal a container with respect to a printing chamber volume of the printing system, the container to hold the printing material. The printing system comprises a lifting system to move the container between a first position in which the container is to be lifted and a second position at which the container is lifted and contacts the seal so as to seal the container. The lifting system is to non-hyperstatically constrain the container.

Abstract: A method and system for a three dimensional printing system are described herein. In one example, the three dimensional printing system has a moveable carriage, an array of laser modules and a print controller. In this example, the moveable carriage has a print head arranged to selectively deposit a printing agent on to a layer of build material as the moveable carriage is moved relative to the layer of build material. The printing agent controls localized fusing of the build material on application of energy. The print controller is communicatively coupled to the array of laser modules and controls activation of individual laser modules of the array of laser modules so as to apply, selectively, energy to addressable sub-regions of the layer of build material on which printing agent has been deposited to control fusing together with the deposited printing agent.

Abstract: In one example In accordance with the present disclosure, a fluid ejection device is described. The fluid ejection device Includes a number of nozzles to eject fluid. Each nozzle Includes multiple firing chambers to hold fluid. The multiple firing chambers are separated: by a chamber partition. Each nozzle also includes a shared nozzle orifice in a substrate through which to dispense fluid. Each nozzle also Includes multiple ejectors, at least one ejector disposed in each firing chamber, in a common channel of the nozzle, fluid from the multiple firing chambers Is mixed, A height of the common channel is defined by the substrate and the chamber partition and is less than a width of the shared nozzle orifice.

Abstract: According to one example, there is provided apparatus for generating a three-dimensional object. The apparatus comprises a build material distributor movable bi-directionally in a first axis to deposit successive layers of a build material on a support, and an agent distributor movable bi-directionally in a second axis different to the first axis to deliver an agent onto selected portions of successive layers of build material.

Abstract: A removable build module to connect to a host apparatus, may include a build platform to support an object-to-be-built, a drive unit to move the build platform, a memory to receive and store build parameters, and an interface circuit to communicate the build parameters to the host apparatus.

Abstract: In one example, an additive manufacturing system. An unsealed air supply enclosure for clean air is maintained at a first pressure above an ambient air pressure to inhibit unfiltered ambient air from leaking into the enclosure. An unsealed processing chamber is maintained at a second pressure below the ambient air pressure to inhibit processing chamber air from leaking out of the processing chamber. An air pathway is disposed between the air supply enclosure and the processing chamber to provide clean air from the air supply enclosure to the processing chamber.

Abstract: A transport device (106) includes a first volume (110) to receive a build material and a second volume (108) to contain an object created by an additive manufacturing system (100). The transport device (106) is receivable by a 3D printer (102) of the additive manufacturing system, and the 3D printer to build the object in the second volume. The transport device (106) is receivable by an extracting and supply device (104). The extracting and supply device is to extract the object from the second volume and to supply the build material to the first volume.

Abstract: Examples of temperature measurement calibration in an additive manufacturing system are described. In one case, a method of calibrating a non-contact temperature measurement device involves applying energy from a radiation source of the additive manufacturing system to heat a reference element. The reference element is thermally coupled to a temperature sensor. A temperature reading from the temperature sensor is compared with data from the non-contact temperature measurement device to calibrate the device.

Abstract: According to one example, there is provided a method of additive manufacturing that comprises obtaining data relating to a 3D object to be manufactured, forming a layer of build material on a build platform, applying a cooling agent in a pattern surrounding a portion of build material to be solidified, and applying energy only to the build material on which cooling agent is applied and to the surrounded portion of build material such that the surrounded portion of build material heats up sufficiently to coalesces, and such that build material on which cooling agent is applied is cooled by the cooling agent and is prevented from heating up sufficiently to coalesce.

Abstract: In an example, a method includes forming a layer of build material and selectively applying fusing agent on to the layer based on a predetermined pattern. Energy may be applied to the layer of build material, and at least one temperature of the layer may be measured. A temperature distribution over the layer of build material may be determined, the temperature distribution indicating, for each of a plurality of locations on the layer of build material, whether fusing agent is present at that location. At least one characteristic derived from the temperature distribution may be compared to a predetermined characteristic. When the compared characteristics differ, an operational characteristic of an additive manufacturing apparatus may be adjusted.

Abstract: An apparatus (100) for generating three dimensional objects comprises a first scanning carriage (102). The first scanning carriage comprises a first energy source (104) to pre-heat an area of a build surface as the first scanning carriage (102) moves over the build surface.

Abstract: An example of an additive manufacturing system is disclosed. The example disclosed herein comprises a build material distributor, a preheating source, and a controller. The build material distributor is to form build material layers from an intended build material having a color. The preheating source is to emit energy at a wavelength related to the intended build material color so that at least a 40% of the energy is absorbed by the build material. The controller is to receive printing instructions to print a 3D object, wherein the printing instructions define an area to be fused in a build material layer. The controller is also to instruct the build material distributor to form the build material layer. The controller is further to control the preheating source to emit energy to preheat a zone comprising the area to be fused.

Abstract: An example of an additive manufacturing system is disclosed. The example disclosed herein comprises a build material distributor, a color module, a preheating source, and a controller. The build material distributor is to form build material layers. The color module is to eject a composition that dyes a build material layer with a color. The preheating source is to emit energy at a wavelength related to the dyed build material color so that at least a 40% of the energy is absorbed by the dyed build material. The controller is to receive printing instructions to print a 3D object, wherein the printing instructions define an area to be fused in a build material layer. The controller is also to instruct the build material distributor to form the build material layer. The controller is to instruct the color module to eject the composition to color the build material from the build material layer in a zone comprising the area to be fused.