Abstract: A method for printing a 3D part in a layer-wise manner includes providing a pool of polymerizable liquid in a vessel over a build window and positioning a downward-facing build platform in the pool, thereby defining a build region above the build window. The method includes selectively curing a volume of polymerizable liquid in the build region by imparting electromagnetic radiation through the build window to form a printed layer of the part adhered to the build platform and actively cooling the build window to remove energy imparted by the electromagnetic radiation and the polymerization reaction of the polymerizable liquid such that the printed layer is between about 1° C. and about 30° C. below an average part temperature prior to raising the print layer and printing the next layer.

Abstract: A liquefier assembly for use in an additive manufacturing system to print three-dimensional parts. In one aspect, the liquefier assembly includes a liquefier that is transversely compressible, and having an inlet end configured to receive a consumable material in a solid or molten state and an outlet end, a nozzle at the outlet end, and an actuator mechanism configured to transversely compress and expand the liquefier in a controlled manner In another aspect, the liquefier assembly is self heating.

Abstract: A method of producing a 3D part using a selective deposition based additive manufacturing system can include developing a first layer using at least one electrostatography engine, determining a first cross-track offset distance between an average cross-track symmetry line of the first layer and a centerline of a transfer medium, transferring the first layer to the transfer medium such that the average cross-track symmetry line of the first layer is aligned with the centerline of the transfer medium, moving a build platform relative to the transfer medium in the cross-track direction to align the first layer on a part build surface, and transfusing the first layer on the build platform using a transfusion assembly to build the part in a layer-by-layer manner. The first layer comprises at least one of a part material and a support material. The first cross-track offset distance is measured in a cross-track direction perpendicular to an in-track direction of movement of the transfer medium.

Abstract: A method of delivering charge to a remote target includes pressurizing a reservoir of metallic conductor initially at a temperature below its melting point. The method includes flowing the metallic conductor through an orifice to form a continuous thread with axial velocity, so that a user might direct the axial velocity of the thread to intercept the remote target. The method further includes applying a potential differential along the thread so that electrical current flows between the reservoir and the remote target.

Abstract: A large-scale additive manufacturing system for printing a structure includes an extrusion system and a knitting system. The extrusion system includes a nozzle configured to receive a supply of structural material and to selectively dispense the structural material in flowable form, and a first gantry configured to move the nozzle along toolpaths defined according to a structure to be printed such that structural material may be dispensed along the toolpaths to print a series of structural layers, wherein the series of structural layers bond together to form all or a portion of the structure.

Abstract: A print assembly for use in an additive manufacturing system to print three-dimensional parts, which includes a coarse positioner, a fine positioner, and a liquefier assembly, where a portion of the liquefier assembly is operably mounted to the fine positioner such that the fine positioner is configured to move the portion of the liquefier assembly relative to the coarse positioner.

Abstract: A method of producing a part printed in a layer-wise manner includes providing a pre-fabricated starter piece with a first course of loops and printing a layer of a part by extruding one or more flowable thermoplastic materials about the existing course of loops such that an upper surface of the layer is at a selected height on the existing course of loops. The method includes knitting a next course of loops to the existing course of loops to form a portion of an internal woven reinforcement network, and printing a next layer of the part by extruding one or more flowable thermoplastic materials about the next course of loops such that an upper surface of the next layer is at a selected height on the next course of loops, wherein the next course of loops extends above the structure being printed and may function as an existing course of loops for subsequent knitting steps.

Abstract: A 3D printer is configured to print a 3D part. The 3D printer includes a print head carried by a head gantry and configured to operably move the print head along planar tool paths. The 3D printer includes at least one head gantry actuator coupled to the head gantry and configured to move the print head in a plane and a print head actuator coupled to the print head and configured to move the print head in a direction substantially orthogonal to the plane. A sensor is fixedly mounted to the print head and configured to output a first signal that is directly or indirectly related to an acceleration of the print head, and a gyroscope is fixedly mounted to the print head and configured to output a second signal related to a rotational position of the print head.

Abstract: A magnetically throttled liquefier assembly for use in an additive manufacturing system and configured to heat a metal-based alloy to an extrudable state includes an array of magnets to generate a magnetic field in order to induce a viscosity in the heated metal-based alloy and to control the flow rate of the heated metal-based alloy through the liquefier for extrusion and the building of a three-dimensional object with the metal-based alloy.

Abstract: Disclosed are selective deposition-based additive manufacturing systems (10) and methods for printing a 3D part (26). Layers of a powder material (22) are developed using one or more electrostatographic engines (12a-d). The layers (22) are transferred for deposition on a part build surface (88). For each of the layers (22), the part build surface (88) is pre-heated by impinging a first heat transfer liquid (74) toward the part build surface (88), for example using a solder fountain. The developed layer (22) is pressed into contact with the heated part build surface (88) to heat the developed layer (22) to a flowable state and form a new part build surface (88) which is fully consolidated. The new part build surface (88) is then rapidly cooled to remove the heat energy added during heating step before repeating the steps for the next developed layer (22).

Abstract: A method of selective deposition-based additive manufacturing includes conveying a layer (28) of material to previously built layers (22) of material. A determination is made as to whether at least one of the conveyed layers (28) of material and a top previously built layer (22) of material contains an unsupported portion (302). When at least one of the conveyed layer (28) of material and the top previously built layer (22) of material contains an unsupported portion, a first set of steps (306, 408, 506) are used to transfer the conveyed layer (28) of material to the top previously built layer (22) of material. When neither of the conveyed layer (28) of material and the top previously built layer (22) of material contains an unsupported portion, a second set of steps (304, 406, 504) are used to transfer the conveyed layer (28) of material to the top previously built layer (22) of material.

Abstract: Disclosed are selective deposition based additive manufacturing systems (10) and methods for printing a 3D part. Layers of a powder material (22) are developed using one or more electrostatography-based engines (12). The layers (22) are transferred for deposition on a part build surface. For each of the layers (22), the part build surface is heated to a temperature within a range between a flowable temperature and a thermal oxidation threshold to form a flowable part build surface, and the developed layer (22) is pressed into contact with the flowable build surface (88) to heat the developed layers (22) to a flowable state and form a new part build surface (88) which is fully consolidated. The new part build surface (88) is then cooled to remove the heat energy added during heating step before repeating the steps for the next developed layer.

Abstract: A print assembly 18 for use in an additive manufacturing system 10 to print three-dimensional parts 12, which includes a coarse positioner 40, a fine positioner 42, and a liquefier assembly 20, where a portion of the liquefier assembly 20 is operably mounted to the fine positioner 42 such that the fine positioner 42 is configured to move the portion of the liquefier assembly 20 relative to the coarse positioner 40.

Abstract: In a method of producing a 3D part using an electrophotography-based additive manufacturing system, a plurality of layers of a powder-based material are developed using at least one electrophotography (EP) engine. The developed layers are transferred to a transfer medium. The layers on the transfer medium are dried by heating the layers without fully fusing the powder-based material to itself using a dryer. This reduces a water content of the layers. The dried layers are heated on the transfer medium to at least a fusion temperature, at which the power-based material fuses together, using a pre-transfusion heater. The dried layers are then transfused together on a build platform using a transfusion assembly to build the part in a layer-by-layer manner.

Abstract: Embodiments herein relate to substrates for use in a selective toner electrophotographic process (STEP) additive manufacturing system. The substrates include a build platform for use in STEP additive manufacturing system, the build platform comprising a build substrate for receiving a build material deposited by a STEP process; wherein the platform has selected thermal properties, such as within 30 percent of the build material to be deposited onto the substrate.

Abstract: A consumable material for use in an extrusion-based digital manufacturing system, the consumable material comprising a length and a cross-sectional profile of at least a portion of the length that is axially asymmetric. The cross-sectional profile is configured to provide a response time with a non-cylindrical liquefier of the extrusion-based digital manufacturing system that is faster than a response time achievable with a cylindrical filament in a cylindrical liquefier for a same thermally limited, maximum volumetric flow rate.

Abstract: A print assembly for use in an additive manufacturing system to print three-dimensional parts, which includes a coarse positioner, a fine positioner, and a liquefier assembly, where a portion of the liquefier assembly is operably mounted to the fine positioner such that the fine positioner is configured to move the portion of the liquefier assembly relative to the coarse positioner.

Abstract: A method of producing a part printed in a layer-wise manner includes providing a pre-fabricated starter piece with a first course of loops and printing a layer of a part by extruding one or more flowable thermoplastic materials about the existing course of loops such that an upper surface of the layer is at a selected height on the existing course of loops. The method includes knitting a next course of loops to the existing course of loops to form a portion of an internal woven reinforcement network, and printing a next layer of the part by extruding one or more flowable thermoplastic materials about the next course of loops such that an upper surface of the next layer is at a selected height on the next course of loops, wherein the next course of loops extends above the structure being printed and may function as an existing course of loops for subsequent knitting steps.

Abstract: An electrostatic-based layer-wise manufacturing system (e.g., 200; 200-1; 250; 282; 300) decouples a layer imaging process from a layer transfusion process.

Abstract: An electrophotography-based additive manufacturing system (e.g., 10; 100; 200; 300; 350; 500; 700) having at least one electrophotography (EP) or electrostatographic engine (e.g., 12; 12p; 12s; 612p; 612p; 712-1; 712-2) and being configured such that a plurality of independently movable parts is built in parallel at a plurality of decoupled processing stations.