Electromagnetic shielding apparatus for induction heated print head for 3D printer
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-02-04
- Publication Date
- 2026-08-13
Smart Images
Figure US2026013835_13082026_PF_FP_ABST
Abstract
Description
TITLE OF INVENTIONELECTROMAGNETIC SHIELDING APPARATUS FOR INDUCTION HEATED PRINT HEAD FOR 3D PRINTER
[0001] A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the reproduction of the patent document or the patent disclosure, as it appears in the U.S. Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.CROSS-REFERENCES TO RELATED APPLICATIONS
[0002] This application is an international application claiming priority to U.S. Provisional Patent Application Serial No. 63 / 753,507 filed February 4, 2025, and entitled “Electromagnetic Shielding Apparatus for Induction Heated Print Head for 3D Printer.”TECHNICAL FIELD
[0003] The present disclosure relates generally to the field of additive manufacturing, also known as 3D printing. More particularly, the present disclosure pertains to mitigating the effects of electromagnetic interference caused by a print head heated via induction heating.BACKGROUND ART
[0004] Metal additive manufacturing (AM), also known as metal 3D printing, is the process of adding material over time to create a solid metal part, as opposed to removing material from a piece of stock. Many methods of metal AM utilize metallic powder as feed material, thoughthis carries its share of issues. In some applications, a wire or rod feedstock would be preferable, along for safer, less expensive, and less prone to contamination and storage factors.
[0005] One such method of heating this wire or rod to a molten temperature is through use of induction heating. Induction heating relies on an electromagnetic field to interact with electrically conductive materials placed within a coil. This material creates what are known as “eddy” currents which in turn create high resistance, causing rapid heat generation within the conductive material.
[0006] This induction can be used to directly heat wire or rod, or to heat a crucible / nozzle print head assembly, which the feed wire or rod is directed into. This melts the feed material and extrudes it based on the pressure from incoming material. A shielding gas can be provided to the print head to prevent oxidation and provide an inert environment for the molten material. This also prevents the feed material from overheating prematurely and weakening during the feed process.SUMMARY OF INVENTION
[0007] This Brief Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
[0008] In view of limitations associated with electromagnetic interference generated during induction heating in metal additive manufacturing systems, an exemplary object of the present disclosure may be to provide an electromagnetic shielding apparatus configured to attenuate electromagnetic field effects outside of a print head during operation. Such electromagneticinterference may undesirably couple to surrounding metallic structures, including build plates, frames, or motion components, thereby reducing efficiency or causing unintended heating.
[0009] In a particular embodiment, an electromagnetic shielding apparatus for a metal additive manufacturing print head as disclosed herein may include a print head for dispensing a metallic deposit, an induction heating coil surrounding the print head, and an electromagnetic shield surrounding both the induction heating coil and the print head. The electromagnetic shield may be configured to attenuate electromagnetic field effects generated by the induction heating coil outside of the electromagnetic shield.
[0010] In an exemplary aspect according to the above-referenced embodiment, the electromagnetic shield may be formed as a Faraday cage.
[0011] In an exemplary aspect according to the above-referenced embodiment, the Faraday cage may include a plurality of openings having a maximum opening dimension smaller than a wavelength of an electromagnetic field generated by the induction heating coil.
[0012] In an exemplary aspect according to the above-referenced embodiment, the maximum opening dimension of the plurality of openings may be between about 0.031 inches and about 2.75 inches.
[0013] In an exemplary aspect according to the above-referenced embodiment, each of the plurality of openings may be circular, square, diamond, oval, rectangular, or combinations thereof.
[0014] In an exemplary aspect according to the above-referenced embodiment, electromagnetic field effects generated by the induction heating coil may be substantially reduced outside of the electromagnetic shield.
[0015] In an exemplary aspect according to the above-referenced embodiment, the metallic deposit dispensed by the print head may comprise metallic powder.
[0016] In an exemplary aspect according to the above-referenced embodiment, the metallic deposit dispensed by the print head may comprise extruded metal.
[0017] In an exemplary aspect according to the above-referenced embodiment, the metallic deposit dispensed by the print head may comprise metal wire.
[0018] In an exemplary aspect according to the above-referenced embodiment, the electromagnetic shield may be affixed to a print head mounting bracket.
[0019] In an exemplary aspect according to the above-referenced embodiment, the electromagnetic shield may be formed to conform to a geometry of the print head such that motion of the print head is not restricted during printing.
[0020] In an exemplary aspect according to the above-referenced embodiment, the electromagnetic shield may include an opening configured to allow a nozzle of the print head to extend outward for material deposition.
[0021] In an exemplary aspect according to the above-referenced embodiment, a thermally insulative layer may be positioned between the electromagnetic shield and the induction heating coil.
[0022] In an exemplary aspect according to the above-referenced embodiment, a temperature monitoring device may be provided and configured to monitor a temperature of the print head.
[0023] In another particular embodiment, a method of reducing electromagnetic interference in a metal additive manufacturing system as disclosed herein may include inductively heating a print head using an induction heating coil to melt metallic feedstock, and surrounding the induction heating coil and the print head with an electromagnetic shield such that electromagnetic field effects outside the electromagnetic shield are attenuated during printing.
[0024] In an exemplary aspect according to the above-referenced method embodiment, surrounding the induction heating coil may comprise enclosing the induction heating coil and the print head with a Faraday cage.
[0025] In an exemplary aspect according to the above-referenced method embodiment, the Faraday cage may include a plurality of openings having a maximum opening dimension smaller than a wavelength of an electromagnetic field generated by the induction heating coil.
[0026] In an exemplary aspect according to the above-referenced method embodiment, a thermally insulative layer may be positioned between the electromagnetic shield and the induction heating coil.
[0027] In an exemplary aspect according to the above-referenced method embodiment, a temperature of the print head may be monitored during inductive heating using a thermocouple or thermistor extending through an opening in the electromagnetic shield.
[0028] In an exemplary aspect according to the above-referenced method embodiment, attenuation of electromagnetic field effects may reduce inductive heating of metallic structures external to the electromagnetic shield during printing.
[0029] Numerous other objects, advantages, and features of the present disclosure will be readily apparent to those of skill in the art upon review of the following drawings and the detailed description.BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1 shows a front view of an example of the installed electromagnetic shielding around the induction coil and print head.
[0031] Figure 2 shows a side view of the electromagnetic shielding from Figure 1.
[0032] Figure 3 shows a potential configuration for the geometry of the electromagnetic shielding prior to its installation on the print head.
[0033] Figure 4 shows the electromagnetic shielding configuration of Figure 1 with the front section lowered to allow visibility of the coil and print head.
[0034] Figure 5 shows the lower front view of the electromagnetic shielding configuration of Figure 1 to incorporate the nozzle.
[0035] Figure 6 shows a bottom view of the electromagnetic shielding configuration of Figure 1.DESCRIPTION OF EMBODIMENTS
[0036] Reference will now be made in detail to embodiments of the present disclosure, one or more drawings of which are set forth herein. Each drawing is provided by way of explanation of the present disclosure and is not a limitation. It will be apparent to those skilled in the art that various modifications and variations can be made to the teachings of the present disclosure without departing from the scope of the disclosure. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment.
[0037] Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents. Other objects, features, and aspects of the present disclosure are disclosed in, or are obvious from, 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 disclosure.
[0038] Unless specifically stated otherwise, any part of the apparatus of the present disclosure may be made of any appropriate or suitable material including, but not limited to, metal, alloy, polymer, polymer mixture, wood, composite, or any combination thereof.
[0039] Referring to Figures 1-6, an electromagnetic shielding apparatus may include an electromagnetic shielding 1 is placed around an induction coil 2 used to heat a print head 3 for extrusion of metal feed stock (not pictured) in a metal 3D printer system 4. This feedstock may be metallic powder, wire, rod, extruded metal, or another form of metal. Although illustrated in connection with a printer system 4, the electromagnetic shielding apparatus 1 may be provided as a standalone assembly for use with a metal additive manufacturing print head. This printer may include a frame 5 supporting components of the printer 4 and motion gantry 6. The printer 4 may also include a print head 3 connected to the motion gantry and designed to receive the feed stock, melt it, and deposit it onto a build plate (not pictured). This printer 4 may include a build chamber 7 formed from a plurality of walls. This build chamber 7 allows for a closed environment during printing.
[0040] As shown in Figures 1, 2, and 4, the electromagnetic shielding 1 is formed to fit the geometry of the print head 3 so that it can encompass the induction coil 2. The form of the electromagnetic shielding 1 is designed such that it will not restrict motion of the print head 3 or collide with other aspects of the printer 4 during operation. In some embodiments, the electromagnetic shielding 1 attenuates electromagnetic field effects generated by the induction coil 2 outside of the electromagnetic shielding 1. This electromagnetic shielding 1 is affixed to the print head mounting bracket 8. This can be done through a number of means, including, but not limited to, fasteners such as screws or bolts, metallic wire loops tightened to the print head, hooks affixed to the print head mounting bracket 8, or another form of fastener.
[0041] Contained within the electromagnetic shielding apparatus is an induction coil 2, with a workpiece for melting the material suspended within it, such as a crucible / nozzle 12. In this iteration, the crucible / nozzle 12 is held in place by an electrically and thermally insulative housing 9. Both this housing and the electromagnetic cage have a small opening to allow for a temperature monitoring device, such as a thermocouple 10 or thermistor to monitor the temperature of the print head 3 during inductive heating. Layers of insulation 11 can be used to line the bottom of the electromagnetic shielding 1 to add further protection against contact between the induction coil 2 and electromagnetic shielding 1. This insulation 11 can be made from a variety of materials, including but not limited to ceramic fiber such as alumina oxide or alkaline earth silicate, mineral wool, fiberglass, composite paper, rigid silica, millboard, fire brick, or another high-temperature insulative material. This range for temperature resistance can extend from a max temp of 300°F to 1300°F.
[0042] The electromagnetic shielding 1 itself can be formed using a variety of techniques. In the iteration demonstrated in the figures, a Faraday cage is used for shielding. This configuration of Faraday cage is made from aluminum, but could also be made from copper, brass, nickel, silver, steel, tin, gold, or another conductive material. A Faraday cage often contains perforations or openings. These openings must be significantly smaller than the wavelength of the electromagnetic field generated by the induction coil 2, and can vary based on the specific induction coil 2 design. The openings in this cage can be circular, square, diamond, oval, rectangular or another geometry. The maximum opening dimension is the longest length of the opening geometry. In a circle, this dimension is the diameter, but in other geometries it is the longest length between two points on the opening. The maximum opening dimension may be between about 0.031 inches and about 2.75 inches. This cage can be custom manufactured, or modified from premade expanded metal panel, perforated metal panels,metallic mesh or wire cloth, metallic grating or other options for premade conductive materials. An opening 13 may be made in the bottom section of the electromagnetic shielding 1 to allow for the nozzle to extend out of the electromagnetic shielding 1 for the purpose of material deposition. This opening 13 may be closely fitted to the insulative housing 9 or another part of the print head 3.
[0043] Other options for the electromagnetic shielding 1 include a conductive film, foil, or a sheet enclosing the print head 3 and induction coil 1. This can be made out of the same materials as the perforated cage described above, so long as it is electrically conductive. Additionally, metallic ink could be used to shield the coil. This ink is comprised of a carrier material that contains metallic particulates such as nickel or copper. This could be used to coat the interior of an enclosure for the print head 2 that is not conductive, such as ceramic or another material, thereby attenuating electromagnetic field effects outside of the enclosure.
[0044] Throughout the specification and claims, the following terms take at least the meanings explicitly associated herein, unless the context dictates otherwise. The meanings identified below do not necessarily limit the terms, but merely provide illustrative examples for the terms. The meaning of “a,” “an,” and “the” may include plural references, and the meaning of “in” may include “in” and “on.” The phrase “in one embodiment,” as used herein does not necessarily refer to the same embodiment, although it may.
[0045] Although embodiments of the present invention have been described in detail, it will be understood by those skilled in the art that various modifications can be made therein without departing from the spirit and scope of the invention as set forth in the appended claims.
[0046] This written description uses examples to disclose the invention and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention isdefined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
[0047] It will be understood that the particular embodiments described herein are shown by way of illustration and not as limitations of the invention. The principal features of this invention may be employed in various embodiments without departing from the scope of the invention. Those of ordinary skill in the art will recognize numerous equivalents to the specific procedures described herein. Such equivalents are considered to be within the scope of this invention and are covered by the claims.
[0048] All of the compositions and / or methods disclosed and claimed herein may be made and / or executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of the embodiments included herein, it will be apparent to those of ordinary skill in the art that variations may be applied to the compositions and / or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit, and scope of the invention. All such similar
[0049] substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope, and concept of the invention as defined by the appended claims.
[0050] The previous detailed description has been provided for the purposes of illustration and description. Thus, although there have been described particular embodiments of a new and useful invention, it is not intended that such references be construed as limitations upon the scope of this disclosure except as set forth in the claims that will come with the full utility filing.
Claims
CLAIMSWhat is claimed is:
1. An electromagnetic shielding apparatus for a metal additive manufacturing print head, the electromagnetic shielding apparatus comprising:a print head for dispensing metallic deposit;an induction heating coil surrounding the print head; andan electromagnetic shield surrounding the induction heating coil and the print head, wherein the electromagnetic shield is configured to attenuate electromagnetic field effects generated by the induction heating coil outside of the electromagnetic shield.
2. The electromagnetic shielding apparatus of claim 1, wherein the electromagnetic shield is a faraday cage.
3. The electromagnetic shielding apparatus of claim 2, wherein the Faraday cage includes a plurality of openings having a maximum opening dimension smaller than a wavelength of an electromagnetic field generated by the induction heating coil.
4. The electromagnetic shielding apparatus of claim 3, wherein a maximum opening dimension of the plurality of openings is between about 0.031 inches and about 2.75 inches.
5. The electromagnetic shielding apparatus of claim 3, wherein each of the plurality of openings are circular, square, diamond, oval, rectangular, or combinations thereof.
6. The electromagnetic shielding apparatus of claim 1, wherein the electromagnetic shield substantially reduces electromagnetic field effects generated by the induction heating coil outside the electromagnetic shield.
7. The electromagnetic shielding apparatus of claim 1, wherein the metallic deposit is metallic powder.
8. The electromagnetic shielding apparatus of claim 1, wherein the metallic deposit is extruded metal.
9. The electromagnetic shielding apparatus of claim 1, wherein the metallic deposit is metal wire.
10. The electromagnetic shielding apparatus of claim 1, wherein the electromagnetic shield is affixed to a print head mounting bracket.
11. The electromagnetic shielding apparatus of claim 1, wherein the electromagnetic shield is formed to conform to a geometry of the print head such that motion of the print head is not restricted during printing.
12. The electromagnetic shielding apparatus of claim 1, wherein the electromagnetic shield includes an opening configured to allow a nozzle of the print head to extend outward for material deposition13. The electromagnetic shielding apparatus of claim 1, further comprising a thermally insulative layer positioned between the electromagnetic shield and the induction heating coil.
14. The electromagnetic shielding apparatus of claim 1, further comprising a temperature monitoring device configured to monitor a temperature of the print head.
15. A method of reducing electromagnetic interference in a metal additive manufacturing system, comprising:inductively heating a print head using an induction heating coil to melt metallic feedstock; andsurrounding the induction heating coil and the print head with an electromagnetic shield to attenuate electromagnetic field effects outside the shield during printing.
16. The method of claim 15, wherein surrounding the induction heating coil comprises enclosing the induction heating coil and the print head with a Faraday cage.
17. The method of claim 16, wherein the Faraday cage includes a plurality of openings having a maximum opening dimension smaller than a wavelength of an electromagnetic field generated by the induction heating coil.
18. The method of claim 15, further comprising positioning a thermally insulative layer between the electromagnetic shield and the induction heating coil.
19. The method of claim 15, further comprising monitoring a temperature of the print head during inductive heating using a thermocouple or thermistor extending through an opening in the electromagnetic shield.
20. The method of claim 15, wherein attenuating electromagnetic field effects reduces inductive heating of metallic structures external to the electromagnetic shield during printing.