Abstract: A printing apparatus is disclosed herein. The apparatus comprises a first carriage, moveable along an axis, comprising a first print agent dispenser to selectively eject a first set of print agents; a second carriage, moveable along the axis, comprising a second print agent dispenser to selectively eject a second set of print agents to the build material layer; and a controller. The controller is to receive data corresponding to a print job; determine a first amount of the first set of print agents and a second amount of the second set of print agents to be ejected at a print area based on the received data; determine a first delay between the ejection of the first amount of the first set of print agents and the second amount of the second set of print agents at the print area; and to independently control the movement of the first and second carriages and the ejection of print agents from the first and second print agent dispensers based on the determined first delay to generate the print job.

Abstract: An additive manufacturing method includes: selecting one of a plurality of irradiation modules based on a selected module having a wavelength band tuned for absorption by a fusing agent to be used to form an object by additive manufacture; plugging the selected module into a socket over the build platform; supporting successive, stacked layers of the object being formed on the build platform; using a liquid dispenser mounted on the carriage, selectively dispensing the fusing agent into an uppermost layer of build material in a pattern corresponding to a layer of the object being formed; and fusing the build material by exposing the fusing agent to a first wavelength band from a first irradiation source in the selected module.

Abstract: A method and apparatus is described in which a signal indicative of an operation of a energy source of a 3D printer during a second predetermined time period commencing with the end of a first predetermined time period is obtained, the first predetermined time period commencing with an activation of the energy source, wherein the energy source is active throughout the first and second time periods; the obtained signal is compared with a reference signal; and it is determined, based on the comparison, whether the energy source is operating according to predetermined characteristics.

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: A 3D printer is disclosed herein. The 3D printer comprises a build material distributor to generate layers of a build material having a right limit temperature of the build material crystallization curve higher than a left limit temperature of the build material fusing curve. The 3D printer also comprises an agent distributor to selectively deposit an energy absorbent fusing agent to a layer of build material; an energy source to emit energy at a set of wavelengths comprised in the range of 430 to 1200 nm; and a controller. The controller is to receive print job data of a 3D object to be generated; control the build material distributor to generate a layer of build material; control the agent distributor to selectively deposit the fusing agent based on the print job data; and to control the energy source to emit energy to the layer of build material to cause build material on which the fusing agent was deposited to melt, coalesce and then solidify upon cooling.

Abstract: In one example a system is for post-processing a three-dimensional (3D) object generated in an additive manufacturing process in which an identifiable agent is applied to a portion of a build material to form a portion of the 3D object. The system comprises an identification unit and a sensor. The identification unit is to cause the identifiable agent to become distinguishable to thereby cause the portion of the 3D object, corresponding to the portion of build material to which the identifiable agent was applied, to be distinguishable from any build material remnant disposed on the 3D object and to which no identifiable agent was applied. The sensor is to distinguish the build material remnant from the portion of the 3D object.

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: 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: 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: It is disclosed a printing system comprising: a print unit and an inertization unit; wherein the print unit is associated to a print chamber being the print chamber to receive print material from a source and the print unit to print the print material within the print chamber and wherein the inertization unit comprises a fuel-cell coupled to a fuel storage and an oxidant fluid input being the oxidant fluid input fluidly connected to the print chamber.

Abstract: An example apparatus to produce a three-dimensional object comprises a controller, a build area configured to receive a layer of particulate material, a printhead, and an ultraviolet light emitting diode energy source. The controller is to cause the printhead to deposit a liquid which absorbs ultraviolet radiation onto the layer of particulate material. The controller is further to cause the ultraviolet light emitting diode energy source to irradiate the liquid, after the liquid has been deposited onto the layer of particulate material, thereby to heat the liquid and cause a portion of the particulate material to solidify.

Abstract: According to one aspect there is provided an apparatus for generating a three-dimensional object. The apparatus may include a first agent distributor to selectively deliver a coalescing agent onto portions of a layer of build material, a second agent distributor to selectively deliver a coalescence modifier agent onto portions of the layer of build material, and a controller to control the first and second distributors to selectively deliver each of the agent and the coalescence modifier onto the layer of build material in respective patterns derived from data representing a slice of a three-dimensional object to be generated, in which when energy is applied to the layer of build material, the build material coalesces and solidifies to form a slice of the three-dimensional object in accordance the patterns and the three-dimensional object has mechanical object properties that are related to the patterns.

Abstract: In one example, an apparatus for generating a three-dimensional object includes an energy source to apply energy to a layer of build material to cause a first portion of the layer to coalesce and solidify, an agent distributor to selectively deliver a cooling agent onto a second portion of the layer, and a controller to control the energy source to apply energy to the layer to cause the first portion to coalesce and solidify in a first pattern and to control the agent distributor to selectively deliver the cooling agent onto the second portion of the layer in a second pattern independent of the first pattern.

Abstract: A 3D printer is disclosed herein. The 3D printer comprises an energy source comprising solid-state emitters to selectively emit energy to a build material layer in a narrow-band of wavelengths; an agent delivery device to selectively deposit a fusing agent, a detailing agent and a reflective agent on the build material layer in respective independent patterns; and a controller. The reflective agent is to reflect substantially all of the energy at the wavelengths within the narrow-band of wavelengths. The controller is to control the agent delivery device to selectively deposit the fusing agent to a build material layer in a first pattern corresponding to a 3D object to be generated. The controller is further to control the agent delivery device to selectively deposit the detailing agent and the reflective gent to the build material layer in a second pattern and third pattern respectively.

Abstract: According to one example, there is provided an apparatus to process volume of particulate build material. The apparatus comprises a sealable chamber to house a volume of particulate build material, a gas supply to supply the chamber with a predetermined gas, a gas circulator to circulate the gas within the volume of build material, a temperature controller to heat the circulated gas to a predetermined heating temperature to heat the volume of build material to the heating temperature and then to cool the circulated gas to a predetermined cooling temperature to cool the volume of build material to the cooling temperature.

Abstract: According to examples, a build module may include a housing, a build material chamber, and a build chamber. The build material chamber may be positioned beneath the build chamber in the housing and may include a moveable support member, in which a build material distributor is to supply successive layers of build material onto the moveable support member from the build material chamber. The build module may be removably insertable into a build receiver of an additive manufacturing system to allow the additive manufacturing system to solidify a portion of the successive layers received onto the moveable support member during the solidification process of the build material. The moveable support member may separate the build material chamber from the build chamber to block build material from the above the build material chamber from being received into the build material chamber during a solidification process of the build material.

Abstract: An example apparatus to produce a three-dimensional object comprises a controller, a build area configured to receive a layer of particulate material, a printhead, and an ultraviolet light emitting diode energy source. The controller is to cause the printhead to deposit a liquid which absorbs ultraviolet radiation onto the layer of particulate material. The controller is further to cause the ultraviolet light emitting diode energy source to irradiate the liquid, after the liquid has been deposited onto the layer of particulate material, thereby to heat the liquid and cause a portion of the particulate material to solidify.

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: According to examples, a build module may include a housing, a build material chamber, and a build chamber. The build material chamber may be positioned beneath the build chamber in the housing and may include a moveable support member, in which a build material distributor is to supply successive layers of build material onto the moveable support member from the build material chamber. The build module may be removably insertable into a build receiver of an additive manufacturing system to allow the additive manufacturing system to solidify a portion of the successive layers received onto the moveable support member during the solidification process of the build material. The moveable support member may separate the build material chamber from the build chamber to block build material from the above the build material chamber from being received into the build material chamber during a solidification process of the build material.

Abstract: A system comprising a support member to support a three-dimensional printed job. The three-dimensional printed job has at least one printed part and associated excess build material. The system further includes a force generating arrangement to impart a force on a three-dimensional printed job supported by the support member; and a build material outlet to allow removal of excess build material from a three-dimensional printed job supported by the support member. The system further includes a sensor to sense a change in the support member, a three-dimensional printed job supported by the support member or a combination thereof wherein the change is due to removal of excess build material from the three-dimensional printed job; and a controller to modify the force imparted on a three-dimensional printed job supported by the support member, wherein the controller modifies the force in dependence upon the change sensed by the sensor.