Reinforced Fused-Deposition Modeling

Abstract

An apparatus for manufacturing an object includes an extrusion head having an extrusion needle for extruding thermoplastic material associated with one or more fiber strands. The apparatus may further include a turn-table, a more robotic arm for moving the extrusion head and needle, thermoplastic filament and fiber strand spools and thermoplastic filament and fiber strands. A controller is provided for directing the robotic arm, extrusion head and the turn-table. Further, a method for manufacturing an object includes generating a design for the object that substantially satisfies desired structural properties of the object and generating a sequence for extruding one or more beads of thermoplastic material to manufacture the object according to the design, in which the one or more beads of thermoplastic material are associated with one or more fiber strands. The one or more beads of thermoplastic material and the associated one or more fiber strands are then extruded according to the sequence.

Claims

1-35. (canceled)

36. A system for manufacturing at least a portion of a three-dimensional (3D) object adjacent to a support, comprising: a source of filament of thermoplastic material, the filament of thermoplastic material comprising a tow of carbon fibers; a support for supporting the at least the portion of the 3D object during manufacturing; a positioning assembly having a dispensing end for directing the filament from the source and into contact with (i) the support or (ii) a previously deposited layer of the 3D object adjacent to the support; a heater configured to subject the filament to heating; a cutter for cutting the tow of carbon fibers to generate the at least the portion of the 3D object; and a controller operatively coupled to the cutter, wherein the controller is configured to: (i) direct the filament from the source toward the dispensing end, and (II) upon directing the filament toward the dispensing end: a. direct the heater to heat the thermoplastic material and the tow of carbon fibers, and b. direct the cutter to cut the tow of carbon fibers to generate a portion of the filament, such that the portion of the filament is deposited towards the support or the previously deposited layer of the 3D object adjacent to the support, thereby manufacturing the at least the portion of the 3D object.

37. The system of claim 36, wherein the controller is configured to direct the filament from the source toward the dispensing end while the dispensing end is moving along a direction relative to the support or the previously deposited layer of the 3D object adjacent to the support.

38. The system of claim 37, wherein the controller directs the dispensing end along the direction relative to the support or the previously deposited layer of the 3D object adjacent to the support to deposit a subsequent portion of the 3D object by repeating (i) and (ii).

39. The system of claim 36, wherein the controller is configured to direct an additional filament toward the dispensing end for deposition over the support or the previously deposited layer of the 3D object adjacent to the support.

40. The system of claim 39, wherein the additional filament is a thermoplastic filament.

41. The system of claim 36, wherein the source of filament is a spool of filament.

42. The system of claim 36, wherein the controller is configured to direct an additional filament inside of the at least the portion of the 3D object.

43. The system of claim 36, further comprising: a build chamber having a bottom surface and configured to enclose the at least the portion of the 3D object during manufacturing; and a drive mechanism configured to move the support relative to the dispensing end, wherein the drive mechanism is mounted on the bottom surface of the build chamber.

44. The system of claim 36, wherein the controller is configured to control a rate at which the filament is directed toward the dispensing end.

45. The system of claim 36, wherein the controller Is configured to direct rotation of the support around a Z-axis, which Z-axis is perpendicular to an XY plane parallel to a surface of the support.

46. The system of claim 36, wherein the controller is configured to direct formation of a support structure from a source of a thermoplastic filament prior to manufacturing the at least the portion of the 3D object.

47. The system of claim 36, wherein the positioning assembly is a multi-axis robotic arm supporting the dispensing end, wherein the multi-axis robotic arm is configured to sequentially deposit the at least the portion of the 3D object.

48. The system of claim 47, wherein the multi-axis robotic arm is a six-axis or seven-axis robotic arm.

49. The system of claim 36, wherein the filament is continuous tow filament.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0086] FIG. 1 depicts a front view of manufacturing system 100 in accordance with the illustrative embodiment of the present disclosure.

DETAILED DESCRIPTION

[0087] FIG. 1 depicts a front view of manufacturing system 100 in accordance with the illustrative embodiment of the present disclosure. Manufacturing system 100 may comprise: [0088] CAD/CAM controller 101, [0089] build chamber 102, [0090] turn-table 110, [0091] one or more robotic arms 121, each comprising an extrusion head 122 with an extrusion needle 123, [0092] thermoplastic filament spool 130-1 and thermoplastic filament 131-1, [0093] thermoplastic filament spool 130-2 and thermoplastic filament 131-2, and [0094] fiber strand spool 130-3 and fiber strand 131-3.
The purpose of manufacturing system 100 is to build a three-dimensional object-depicted as object 151 in FIG. 1.

[0095] CAD/CAM controller 101 directs the building of object 151 based on a mathematical model of object 151. In accordance with the illustrative embodiment, the mathematical model of object 151 is created with CAD/CAM controller 101, but it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present disclosure in which the model is created elsewhere and imported into CAD/CAM controller 101.

[0096] CAD/CAM controller 101 may comprise a list of the desired structural properties of object 151. This list may include, but is not limited to:

[0097] 1. the desired compression strength characteristics of object 151, and

[0098] 2. the desired tensile strength characteristics of object 151, and

[0099] 3. the desired resonance characteristics of object 151.

[0100] In accordance with the illustrative embodiment, thermoplastic filament 131-1 comprises a continuous tow of 5 low-modulus carbon-fiber strands, and thermoplastic filament 131-2 does not comprise a fiber strand. Thermoplastic filament 131-2 is used as support material in building object 151.

[0101] CAD/CAM controller 101 may also comprise a list of the structural properties of thermoplastic filament 131-1. This list may include, but is not limited to: [0102] 1. the compression strength of the thermoplastic and tow of carbon fibers (after deposition and in object 151), and [0103] 2. the tensile strength of the thermoplastic and tow of carbon fibers (after deposition and in object 151), and [0104] 3. the thermal expansion of the thermoplastic and tow of carbon fibers (after deposition and in object 151), and [0105] 4. the Young's modulus of the thermoplastic and tow of carbon fibers (after deposition and in object 151).

[0106] CAD/CAM controller 101 may also comprise a list of the structural properties of thermoplastic filament 131-2 and/or fiber strand 131-3.

[0107] CAD/CAM controller 101 generates a design for object 151 that: [0108] (1) attempts to satisfy the desired structural properties of object 151, and [0109] (2) a sequence for depositing beads of thermoplastic material and support material.
The design for object 151 includes, but is not limited to:

[0110] (i) the location of fiber strands in the object, and

[0111] (ii) the geometry of the fiber strands in the object.

[0112] Build chamber 102 is an enclosed environment in which object 151 is built.

[0113] Turn-table 110 comprises a platform on which object 151 is built. Turn-table 110 may be driven by a drive mechanism 110-1 that is directed by CAD/CAM controller 101. The drive mechanism 110-1 may comprise a motor arrangement including, but not limited to one or more stepper and/or servo motors. Some embodiments may also include a transmission or gear arrangement for controlled transmission of the rotational movement of the motor(s) to the turn-table 110. The transmission or gear arrangement may include without limitation one or more gears, belts, chains, and combinations thereof.

[0114] Various embodiments of the drive mechanism 110-1 may be configured to rotate the turn-table 110 in clockwise and counterclockwise directions around the Z axis under the direction of CAD/CAM controller 101. The drive mechanism 110-1, in various other embodiments, may also be configured to raise and lower the turn-table 110 in the +Z and the −Z directions under the direction of CAD/CAM controller 101. In various other embodiments, the drive mechanism 110-1 may also be configured to move the turn-table 110 in the +X direction, the −X direction, the +Y direction the −Y direction, or any combination thereof.

[0115] The one or more robotic arms 121 may be configured to place the dispensing end of the extrusion needle 123 at any location in the build volume of object 151, from any approach angle. This enables manufacturing system 100 to lay fiber strands on the inside an enclosure such as a closed sphere through a hole in the enclosure (e.g., sphere) just large enough for extrusion needle 123. The robotic arms 121, in various embodiments, may be powered by electric motors, hydraulic actuators, or combinations thereof, and configured to provide three or more axes or degrees of freedom so that the extrusion head/needle can move in the +X direction, the −X direction, the +Y direction, the −Y direction, the +Z direction, the −Z direction, or any combination thereof. In one illustrative embodiment, the robotic arm 121 may be configured as a six-axis robotic arm. In another illustrative embodiment, the robotic arm 121 may be configured as a seven-axis robotic arm. Any other suitable positioning assembly capable of placing the dispensing end of the extrusion needle 123 at any location in the build volume of object 151, from any approach angle, may be used in place of the robotic arms 121.

[0116] The extrusion head 122 is configured to melt the thermoplastic and extrude the molten thermoplastic (which may partially or wholly contain one or more fiber strands) via the extrusion needle 123. Various embodiments of the extrusion head 122 may define an interior chamber 122-1 for receiving the thermoplastic material. The extrusion head 122 may include a heater or heating element 122-2 for melting the thermoplastic material within the chamber for extrusion through the extrusion needle in liquid form. The extrusion head 122 may include a motor (not shown) or any other suitable mechanism for pushing the thermoplastic material through the chamber 122-2 and out the extrusion needle 123. In some embodiments, the extrusion head 122 may also be configured with a cutting mechanism 122-4 to cut the one or more fiber strands to the appropriate length. The cutting mechanism 122-3 may include a blade or other suitable cutting member for cutting the one or more fiber strands. In one illustrative embodiment, the cutting mechanism 122-3 may be disposed at the dispensing end or tip 123-1 of extrusion needle 123.

[0117] Extrusion needle 123 may comprise a hollow tube or nozzle having a first open end that communicates with the chamber of the extrusion head 122 and a second open end (dispending end or tip 123-1) that dispenses the thermoplastic, which may partially or wholly contain one or more fiber strands. The opening of the tip 123-1 may be circular, oval, square, slotted or any other suitable shape that is capable of extruding the thermoplastic material in a desired cross-sectional shape. In various embodiments, the extrusion needle 123 may have a length equal to at least the longest dimension of object 151 so that the tip of 123-1 extrusion needle 123 can deposit material at any location in the build volume of object 151 from any approach angle.

[0118] In operation, according to one illustrative embodiment, one or more motors may be used for feeding the filament(s) of thermoplastic material 131-1, 131-2 (and fiber strand(s) 131-3) into the chamber 122-1 of the extrusion head 122 from the spools 130-1, 130-2, 130-3. The thermoplastic material entering the chamber 122-1 is melted by the heater 122-2, and extruded from the extrusion head 122 via the extrusion needle 123. The CAD/CAM controller 101 may control the rate of the one or more feed motors, the temperature of the heater 122-2, and/or the other process parameters mentioned earlier, so that the thermoplastic material and fiber strand(s) can be extruded in a manner that to attempts to satisfy the desired structural properties of object 151.

[0119] Although the manufacturing system, methods, thermoplastic filaments, fiber strands, and other associated elements have been described in terms of exemplary embodiments, they are not limited thereto. Rather, the appended claims should be construed broadly to include other variants and embodiments of same, which may be made by those skilled in the art without departing from the scope and range of equivalents of the device, tray and their elements.