Rapid prototype extruded conductive pathways

Abstract

A process of producing electrically conductive pathways within additively manufactured parts and similar parts made by plastic extrusion nozzles. The process allows for a three-dimensional part having both conductive and non-conductive portions and allows for such parts to be manufactured in a single production step.

Claims

1. A multi-layer three-dimensional object having a selected area of an electrically conductive portion in a selected area of a non-conducting portion, the electrically conducting portion having an x-ray density substantially equal to the x-ray density of the non-conducting portion.

2. The three-dimensional object according to claim 1 wherein at least one of the electrically conductive portions or the non-conducting portions has an x-ray density additive present.

3. The three-dimensional object according to claim 2 wherein both the electrically conducting portion and the non-electrically conducting portion have an x-ray density additive present.

4. The three-dimensional object according to claim 1 wherein a coloring agent is added to at least one of the electrically conductive or the electrically non-conductive portions so that a color of the conductive and non-conductive portions is essentially uniform.

5. The three-dimensional object according to claim 1 wherein both the electrically conductive and the electrically non-conductive portions have a coloring agent present so that the color of the conductive and non-conductive portions is essentially uniform.

Description

DESCRIPTION OF THE PREFERRED EMBODIMENT

(1) Reference will now be made in detail to the embodiments of the invention, one or more examples of which are set forth below. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the appended claims and their equivalents. Other objects, features, and aspects of the present invention are disclosed in the following detailed description. It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only and is not intended as limiting the broader aspects of the present invention, which broader aspects are embodied in the exemplary constructions.

(2) In accordance with this invention, any number of rapid prototyping apparatuses can be modified as set forth herein to carry out a process for formation of a three-dimensional object having conductive and non-conductive portions therein. U.S. Pat. No. 7,896,639 to Objet Geometries Ltd. describes an apparatus using multiple printing heads for sequentially forming thin layers for a construction material in response to computer controlled data. U.S. Pat. No. 7,896,639 is incorporated herein by reference. Using one or more print heads, as described in the above-referenced application, to dispense a conductive material either in the form of a powder, a binder, or a polymer, a conductive region can be formed in a three-dimensional structure. Suitable conductive powders, binders, or polymers may include carbon nano tubes or fine metallic particles or fibers that are dispensed through the printing heads so as to construct a conductive portion within a three-dimensional part.

(3) U.S. Pat. No. 7,722,802, which is incorporated herein by reference, describes a powder based rapid generative prototyping method. The teachings and methodology described in the '802 patent can be modified as described below in accordance with the present invention.

(4) By controlling the sequential deposition of a conductive powder material, which may include metals, conductive polymers, or a conductive carbon substrate, a three-dimensional body having conductivity there through may be provided. Alternatively, a non-conductive powder may be deposited in and bound together with selectively applied conductive and non-conductive binder. In general, additive manufacturing (AM) represents a technology field that can be used to form three-dimensional objects for solid images. In general, AM techniques build three-dimensional objects, layer by layer, from a building medium using data representing successive cross-sections of the object to be formed. The four primary modes of AM include stereo lithography, laser sintering, ink jet printing of solid images, and fused deposition modeling.

(5) In accordance with the present invention, it is recognized that the present technology directed to using thin layers to form solid structures can be modified such that a portion of the applied thin layers may include conductive materials such as steel wool, copper fibers, other metal fibers, and non-metallic conductive substrates such as carbon based materials including carbon nano tubes or conductive polymers. Suitable conductive polymers which can be applied by one or more of the methodologies described herein include various linear-backbone polymer compounds including polyacetylene, polypyrrole, polyaniline, and their co-polymers and which include various melanins. Included among suitable conductive polymers are poly(fluorine)s, polyphenylenes, polypyrenes, polyazulenes, polynaphthalenes, poly(acetylene)s, poly(p-phenylene vinylene), poly(pyrrole)s, polycarbazoles, polyiridoles, polyazepines, polyanilines, poly(thiophene)s, poly(3,4-ethylenedioxythiophene), poly(p-phenylene sulfide), and combinations thereof. Depending upon the nature of the conductive polymer, suitable applicators can be used based upon the material of choice. Various binders including electrically-conductive materials can also be added to the conductive polymers to enhance the use, application, or electrical-conductivity properties.

(6) By applying such conductive materials within a precise location and geometry, a three-dimensional object having an electrical pathway there through can be provided. Using a similar approach, an electrically conductive object may have an appropriate layer of non-conductive material added where needed as an insulator.

(7) The present process allows for rapid production of a part and/or a prototype in which the electrical properties of the part may be evaluated as well as a more traditional mechanical attributes of the part. The present invention lends itself to the production of integrated circuits within a rapid prototype part of the formation of a rapid prototype circuit board. Any three-dimensional part that lends itself to production through AM processes may be modified such that a component of the three-dimensional structure is supplied through an electrically conductive material. As a result, increased functionality of a prototype can be provided. In addition, to the extent the AM is used to manufacture production parts, technology allows an improved way of supplying three-dimensional parts which require defined pathways of conductive and non-conductive regions.

(8) The present process also lends itself to the production of parts that are more difficult to reverse engineer. A traditional electrically wired device can easily be reverse engineered by tracing the wiring configuration. Even for parts that are concealed within a housing which is designed to render inoperative if the housing is removed, reverse engineering can still be accomplished by the use of x-rays or other imaging technology. For some products, the external housing can be melted or dissolved in an effort to preserve the integrity of the sealed interior portion.

(9) The present invention is more resistant to reverse engineering. While x-rays can be used to determine varying density within the extruded layers, it is possible to provide additives to the various insulating and detector materials such that the layers are not readily differentia table using imaging technology such as x-rays. Absent imaging technology, a physical removal of layers is needed which is more difficult and costly. It is possible to match to colors of the various conductive and non-conductive portions such that visual reconstruction of various layers is not readily apparent.

(10) As a result of using conductive and non-conductive materials having similar densities and colors, one can make the reverse engineering process much more complicated. Such capabilities are a useful aspect for certain embodiments of the present invention.

(11) Although preferred embodiments of the invention have been described using specific terms, devices, and methods, such description is for illustrative purposes only. The words used are words of description rather than of limitation. It is to be understood that changes and variations may be made by those of ordinary skill in the art without departing from the spirit or the scope of the claims of the present invention. In addition, it should be understood that aspects of the various embodiments may be interchanged, both in whole, or in part. Therefore, the spirit and scope of the invention should not be limited to the description of the preferred versions contained therein.