Abstract: A process for three-dimensional modeling in which an alkali-soluble thermoplastic material is used in an additive deposition process to form a soluble support structure (28) for a three-dimensional object (26) under construction. The alkali-soluble thermoplastic material includes a base polymer of carboxylic acid and a plasticizer. Following formation, the object (26) is placed in an alkaline bath to dissolve the support structure (28). The alkali-soluble material can be used to form an alkali-soluble three-dimensional object (26).

Abstract: Disclosed are a filament cassette and a filament loading assembly for supplying filament in a three-dimensional deposition modeling machine. The filament cassette contains a rotatable spool of filament, and has an exit orifice through which a filament strand may exit the cassette. The filament loading assembly is mounted on the modeling machine and receives the filament cassette. The filament loading assembly has conduit for receiving a strand of filament from the cassette and a drive means for advancing the filament strand through the conduit. The filament cassette and loading assembly of the present invention provide a convenient manner of loading and unloading filament from the modeling machine. The filament cassette and the conduit may be made airtight so that the filament is protected from moisture in the environment.

Abstract: Filament is loaded into an extrusion apparatus, such as a three-dimensional deposition modeling machine, by inserting a cassette containing filament into the apparatus. A filament strand from the cassette is then advanced into the machine, such as by operating a thumb wheel or a follower wheel on the cassette. The filament loading method of the present invention provides a convenient manner of loading and unloading filament in a three-dimensional modeling machine, and can be implemented in a manner that protects the filament from environmental moisture.

Abstract: An apparatus which extrudes flowable material from a liquifier includes a system for loading filament supplied in a cassette. The cassette is loaded into a loading bay of the apparatus. A strand of filament from the cassette is engaged and advanced along a path to the liquifier using a drive wheel or roller pair. A conduit having an entrance in the loading bay guides the filament as it is advanced. The filament loading system of the present invention provides a convenient manner of loading and unloading filament in a three-dimensional modeling machine, and can be implemented in a manner that protects the filament from environmental moisture.

Abstract: Disclosed is a multi-tip extrusion apparatus and design methodology whereby a single extrusion head having approximately co-planar, fixed-position dispensing tips is used in a three-dimensional modeling machine to deposit multiple types of materials from distinct material supply sources. The tips are spaced apart a distance great enough so that a road of material extruded by a leading one of the tips will cool and shrink from the plane of the tips so that it is not smeared by contact with a trailing one of the tips.

Abstract: A method for three-dimensional modeling builds up three-dimensional objects in a heated build chamber by dispensing modeling material from a dispensing head onto a base in a predetermined pattern. Physical and thermal separation are maintained between the heated build chamber and motion control components that control the motion of the dispensing head and the base. Thermal isolation of the motion control components from the build chamber allows the chamber to be maintained at a high temperature, and has other practical advantages as well.

Abstract: Disclosed is a three-dimensional modeling apparatus (10) that builds up three-dimensional objects in a heated build chamber (24) by dispensing modeling material from a dispensing head (14) onto a base (16) in a pattern determined by control signals from a controller (140). The motion control components (18, 20) of the apparatus (10) are external to and thermally isolated from the build chamber (24). A deformable thermal insulator (132) forms a ceiling of the building chamber, allowing motion control of the dispensing head (14) in an x, y plane by an x-y gantry (18) located outside of and insulated from the build chamber (24). In the preferred embodiment, a material dispensing outlet (66) of the dispensing head is inside the chamber. Thermal isolation of the motion control components from the build chamber allows the chamber to be maintained at a high temperature.

Abstract: Disclosed are an apparatus and method for three-dimensional deposition modeling, which shield a supply of modeling filament fed through a deposition modeling machine from exposure to environmental moisture. Dry gas under pressure is supplied to a filament path leading from a material supply to a liquifier, creating an active moisture barrier along the filament path. In a preferred embodiment, an entrance of the filament path is configured to seal to an exit orifice of a cassette containing the material supply, and an exit of the filament path is vented to release exhaust gas.

Abstract: High-performance thermoplastic materials are used in building a three-dimensional model and its supports, by fused deposition modeling techniques. In a preferred embodiment, the thermoplastic resin comprising used as the modeling material is selected from the group consisting of a polycarbonate resin, a polyphenylsulfone resin, and a polycarbonate/acrylonitrile-butadiene-styrene resin. An amorphous thermoplastic resin which self-laminates, bonds weakly to the modeling material, has a heat deflection temperature similar to the heat deflection temperature of the modeling material, and has a tensile strength of between 5000 psi and 12,000 psi is used as a support material. In a preferred embodiment, the thermoplastic resin used as the support material is selected from the group consisting of a polyphenylene ether and polyolefin blend, a polyphenylsulfone and amorphous polyamide blend, and a polyphenylsulfone, polysulfone and amorphous polyamide blend.

Abstract: Disclosed are a method and apparatus for initializing an additive process computer-controlled three-dimensional modeling machine which builds models on a modeling platform. The method, without operator intervention, senses the top surface of a substrate or other object mounted on the platform at a variety of preselected x, y locations and records the z-axis positions of the platform corresponding to the sensing of the object. Using the recorded z-axis positions, a z-start position for the modeling platform is calculated. The platform can be automatically placed at the calculated z-start position. The recorded z-axis positions can further be used to define a plane fitted to the substrate top surface. Optionally, the model can be built in a coordinate system defined by the plane.

Abstract: An apparatus and method for controlling the extrusion of thermoplastic through one or more discharge orifices is described. An apparatus comprises one or more thermally conductive flow tubes defining flow channels in a heated thermally conductive body and terminating in discharge orifices. Each flow channel may be independently valved on and off, by selectively supplying a flow of coolant. An array of flow channels can be independently opened and closed in a predetermined pattern, so as to vary the extrudate configuration of thermoplastic emerging from the discharge orifices. By extruding thermoplastic layer-by-layer onto a base in this manner, a three-dimensional object may be formed.

Abstract: Disclosed are a method and apparatus for matching the extrusion rate of a liquifier which extrudes a flow of material to a predetermined target output rate. The present invention adjusts the volumetric rate of material going in to the liquifier to account for a predicted melt flow component of material being extruded from the liquifier. Compensating for the predicted melt flow results in reduced error in an extrusion profile produced by material deposited along a toolpath followed by the liquifier.

Abstract: Disclosed are a method and apparatus for matching the extrusion rate of a liquifier which extrudes a flow of material to a predetermined target output rate. The present invention adjusts the volumetric rate of material going in to the liquifier to account for a predicted melt flow component of material being extruded from the liquifier. Compensating for the predicted melt flow results in reduced error in an extrusion profile produced by material deposited along a toolpath followed by the liquifier.

Abstract: Disclosed is a modeling filament for use as feedstock in a fused deposition modeling liquifier, and a method for manufacturing the filament. The diameter and standard deviation of the filament are controlled to meet various tolerance requirements of jam resistance, slip resistance, model strength, liquifier overflow prevention and hysteresis-free transient response. Standard deviation of the filament diameter is matched to a filament target diameter. The resulting filament is used to form high-quality models.

Abstract: Disclosed are a method and apparatus for building three-dimensional models by deposition modeling techniques from moisture-sensitive thermoplastics. A feedstock of thermoplastic modeling material is dried to a low moisture content and supplied to a dispensing head of a modeling apparatus. The dry thermoplastic material is heated in a liquifier and deposited in a predetermined pattern so as to build a three-dimensional model.

Abstract: A three-dimensional model and its support structure are built by fused deposition modeling techniques, wherein a thermoplastic material containing silicone is used to form the support structure and/or the model. The thermoplastic material containing silicone exhibits good thermal stability, and resists build-up in the nozzle of an extrusion head or jetting head of a three-dimensional modeling apparatus. The silicone contained in a support material acts as a release agent to facilitate removal of the support structure from the model after its completion.

Abstract: Formation of polymeric prototype elements is effected by high pressure and high temperature extrusion of selected materials onto a plate as a ribbon of liquefied polymer comprising poly(2-ethyl-2-oxazoline) and a polar polymer discharged in a programmed pattern.

Abstract: A system for mounting a slab substrate in a three-dimensional modeling machine includes two parallel rails positioned on opposite sides of a modeling platform. A blade extends along each rail, each blade having an inward-facing knife edge. A slab substrate having a width which approximates the distance between the two rails and having slits in its sides is loaded in the machine by lining up the slits, respectively, with each blade and pushing the substrate towards the rear of the platform as the knife edges cut into the substrate. Preferably, the platform includes a rear stopper to stop rearward motion of the substrate. The platform preferably also includes a retaining means at its front edge that is actuated to lock the substrate into place on the platform during modeling. The substrate is removed from the platform by deactuating the retaining means, if any, grasping the substrate, and sliding the substrate towards the front of the platform.

Abstract: Disclosed are an apparatus and method for three-dimensional deposition modeling, which shield a supply of modeling filament fed through a deposition modeling machine from exposure to environmental moisture. Dry gas under pressure is supplied to a filament path leading from a material supply to a liquifier, creating an active moisture barrier along the filament path. In a preferred embodiment, an entrance of the filament path is configured to seal to an exit orifice of a cassette containing the material supply, and an exit of the filament path is vented to release exhaust gas.

Abstract: Disclosed are a filament cassette and a filament loading assembly for supplying filament in a three-dimensional deposition modeling machine. The filament cassette contains a rotatable spool of filament, and has an exit orifice through which a filament strand may exit the cassette. The filament loading assembly is mounted on the modeling machine and receives the filament cassette. The filament loading assembly has conduit for receiving a strand of filament from the cassette and a drive means for advancing the filament strand through the conduit. The filament cassette and loading assembly of the present invention provide a convenient manner of loading and unloading filament from the modeling machine. The filament cassette and the conduit may be made airtight so that the filament is protected from moisture in the environment.