WO2014182302A1

WO2014182302A1 - A modular framework system with emi/rfi suppression for an electronic device

Info

Publication number: WO2014182302A1
Application number: PCT/US2013/040253
Authority: WO
Inventors: Allen J. ROWBOTHAM
Original assignee: GE Intelligent Platforms Embedded Systems, Inc.
Priority date: 2013-05-09
Filing date: 2013-05-09
Publication date: 2014-11-13

Abstract

A frame structure according to various embodiments can include a corner member comprising three mutually perpendicular protrusions and three profile members. Each perpendicular protrusion can be configured having a substantially open cross section. Each profile member can be configured having at least one double angle cut end, which is arranged to fit within and attach to respective perpendicular protrusions such that the double angle cut ends are joined together to form an angled connection within the corner member.

Description

A MODULAR FRAMEWORK SYSTEM WITH EMI/RFI SUPPRESSION FOR AN

ELECTRONIC DEVICE

I. Field of the Invention

[0001] The present disclosure relates generally to a framework systems for housing electrical and electronic equipment where shielding from electromagnetic interference (EMI) and radio frequency interference (RFI) is needed. More particularly, the present disclosure relates to framework systems providing EMI/RFI suppression in which frameworks of various sizes can be configured to vary the frame configuration and to house multiple types of electrical equipment.

II. Background of the Invention

[0002] Electrical and electronic equipment is generally enclosed in an equipment enclosure including a support framework system or chassis which may be fitted with a variety of panels. Conventional framework systems typically are constructed of sets of framework members of modular construction which can be assembled in different combinations to provide frame structures of correspondingly different configurations and sizes. This type of enclosure is commonly referred to as a modular enclosure.

[0003] Modular enclosures are needed in many sizes and configurations to house various devices, such as large, complex devices to simple, compact devices. Typical applications can include housing computer systems, medical instrumentations, control systems, avionics instruments, industrial monitoring systems, etc. To meet the various size demands, a manufacturer is required to produce a large variety of shapes and sizes of different frame members and must maintain an overall diverse inventory of frame members. Such an inventory can be quite expensive. Minimizing the number of parts required to assemble a frame would reduce the expense and complexity of the manufacturing process, the parts inventory, and the overall production costs. Minimizing the number of different parts, along with providing a frame that is easily modifiable to a desired configuration, also simplifies the installation.

[0004] Another challenge with modular enclosures is that the operation of electronic equipment enclosed therewithin often emits EMI/RFI. The most effective way to control EMI/RFI emissions is with shielding. Shielding, through the use of properly grounded conductive materials, reduces electromagnetic fields by reflecting and/or absorbing the energy. If not properly shielded, such radiation can emanate and escape the enclosure, ultimately causing considerable interference with neighboring electronic equipment. The unwanted interference may disrupt, limit, or degrade the effective performance of the neighboring electronic equipment.

[0005] Accordingly, governing bodies such as the Federal Communications Commission (FCC) have established, and are enforcing, regulations dictating that electronic equipment not radiate significant amounts of electromagnetic energy. To prevent EMI/RFI interference, these regulations require that the sources of RF or electromagnetic radiation, within a system, be shielded. The governing bodies closely monitor the maximum amount of electromagnetic energy allowed to escape from the enclosure.

[0006] The above-described shortcomings significantly increase the number of different sized frame members used to configure modular enclosures, increases the parts inventories, and increases the overall production cost. III. Summary of the Invention

[0007] In view of the aforementioned deficiencies, a need exists for a modular enclosure having a framework system comprising standard, though interchangeable, frame members to permit custom applications. These interchangeable frame members desirably also can form different shapes and sizes to accommodate various electronic devices. There also remains a need for a system and method of enclosing an electronic device within a support framework that suppresses EMI/RFI.

[0008] In at least one aspect, the present disclosure provides a frame structure including a corner member and three profile members. The corner member comprises three mutually perpendicular protrusions. Each perpendicular protrusion is configured having a substantially open cross section. Each profile member is configured having at least one double angle cut end arranged to fit within and attach to respective perpendicular protrusions such that the double angle cut ends are joined together to form an angled connection within the corner member.

[0009] In at least another aspect, the present disclosure provides a frame structure including a corner member and three profile members. The corner member comprises three mutually perpendicular protrusions. Each perpendicular protrusion is configured having a substantially open cross section. Each profile member is configured having at least one double angle cut end arranged to fit within and attach to respective perpendicular protrusions. A first EMI/RFI suppression component is positioned substantially along a length of at least one of the profile members. A second EMI/RFI suppression component provided within the side faces of the at least one profile member to form an alternating pattern between adjacent side faces of the at least one profile member. [0010] In yet another aspect, the present disclosure provides a modular frame assembly including a plurality of corners and a plurality of frame members. At least one corner member comprises three mutually perpendicular protrusions. Each perpendicular protrusion is configured having a substantially open cross section. At least three profile members comprise at least one double angle cut end. The at least three profile members are arranged to fit within and attach to respective perpendicular protrusions. The at least three profiles members are configured having identical profile configurations and different lengths such that the at least three profile members are interchangeable to form a variety of frame assemblies having different configurations.

[0011] Further features and advantages of the invention, as well as the structure and operation of various embodiments of the invention, are described in detail below with reference to the accompanying drawings. It is noted that the invention is not limited to the specific embodiments described herein. Such embodiments are presented herein for illustrative purposes only. Additional embodiments will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein.

IV. Brief Description of the Drawings

[0012] FIG. 1 illustrates a perspective view of an assembled framework system in accordance with at least one embodiment of the present disclosure.

[0013] FIG. 2 illustrates a perspective view of the framework system housing an electronic device in accordance with at least one embodiment of the present disclosure. [0014] FIG. 3 illustrates a view of a corner member attached to an outside corner of an electronic device in accordance with at least one embodiment of the present disclosure.

[0015] FIG. 4A illustrates a perspective of an interior view of a corner member in accordance with an embodiment of the present disclosure.

[0016] FIG. 4B illustrates a perspective of an exterior view of a corner member in accordance with an embodiment of the present disclosure.

[0017] FIG. 5 illustrates a perspective view of a frame member in accordance with an embodiment of the present disclosure.

[0018] FIG. 6A illustrates a perspective view of a frame member in accordance with an embodiment of the present disclosure.

[0019] FIG. 6B illustrates a perspective view of a frame member in accordance with an embodiment of the present disclosure.

[0020] FIG. 6C illustrates a perspective view of a frame member in accordance with an embodiment of the present disclosure.

[0021] FIG. 7 illustrates a view of a corner member attached as an inside corner in accordance with an embodiment of the present disclosure.

[0022] The present disclosure may take form in various components and arrangements of components, and in various process operations and arrangements of process operations. The present disclosure is illustrated in the accompanying drawings, throughout which, like reference numerals may indicate corresponding or similar parts in the various figures. The drawings are only for purposes of illustrating preferred embodiments and are not to be construed as limiting the disclosure. Given the following enabling description of the drawings, the novel aspects of the present disclosure should become evident to a person of ordinary skill in the art.

V. Detailed Description of the Drawings

[0023] The following detailed description is merely exemplary in nature and is not intended to limit the applications and uses disclosed herein. Further, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description. While embodiments of the present technology are described herein primarily in connection with industrial controllers, the concepts are also applicable to other types of mounted display controllers.

[0024] FIG. 1 illustrates a modular framework system 100 with EMI/RFI suppression for an electronic device in accordance with an embodiment of the present disclosure. The system 100 includes a frame 102 having a plurality of profile frame members 104. The exemplary system 100 includes 12 profile frame members 104, although the present invention is not so limited. The frame 102 further includes a first end panel 112 and a second end panel 114.

[0025] The first end panel 112 is depicted as a substantially flat square panel. The second end panel 114 is depicted as a flat square panel provided with ventilation holes 115 to promote airflow through the enclosure to facilitate cooling of an electronic device enclosed therein. At the corners, the end panels 112, 114 and the frame members 104 are connected by corner members 116, in a manner described below.

[0026] FIG. 2 illustrates an electronic device 118 enclosed within the frame 102, as shown in FIG. 1, and mounted between a top plate 120 and a bottom plate 122. In this embodiment, the frame 102 includes end panels 112, 114 and side panel 124 attached to a front side of the frame 102. Whether or not the panels are attached to the frame is a matter of application or design choice.

[0027] FIGS. 3, 4A, and 4B illustrate exemplary embodiments of the corner members 116. As illustrated, each corner member 116 is made from a material, such as extruded aluminum, to form three corner forming walls 128, 130 and 132. Each wall 128, 130, 132 is configured to define a horizontal and vertical legs 128a, 128b, 130a, 130b, 132a, 132b, respectively.

[0028] The horizontal and vertical legs are disposed at 90 degree angles relative to one another to form three mutually perpendicular protrusions 126a, 126b, and 126c. For example, a first perpendicular protrusion 126a is formed by legs 128a and 130a. A second perpendicular protrusion 126b is formed by legs 130b and 132a. A third perpendicular protrusion 126c is formed by legs 128b and 132b.

[0029] As shown in FIG. 3, each corner member 116 can be secured to an electronic device 118 at the corner of the frame 102 by screws 134 received into openings 136 formed through the corner member 116. The three mutually perpendicular protrusions 126a, 126b, 126c intersect to form a trihedral arrangement such that the protrusions are capable of connecting to the side, bottom, and top of the enclosed electronic device 118. This trihedral arrangement improves the structural integrity of the frame 102 of the system 100.

[0030] FIG. 4A illustrates an interior view of the corner member 116, and FIG. 4B illustrates an exterior view of the corner member 116. In some embodiments, the corner member 116 may include wedge portions 138a, 138b, and 138c, integrally formed therein, as shown in FIGS. 4A-4B. In other embodiments, as illustrated in FIG. 3, the corner member 116 may not include a wedge portion. [0031] In the exemplary embodiments shown in FIGS. 4A-4B, wedge portions 138a, 138b, and 138c may be formed within walls 128, 130, and 132, respectively, and disposed at an angle to connect the respective horizontal and vertical legs. For example, wedge portion 138a is formed within wall 128 at angle connecting horizontal and vertical legs 128a and 128b.

[0032] Wedge portion 138b is formed within wall 130 at angle connecting horizontal and vertical legs 130a and 130b.

[0033] Wedge portion 138c is formed within wall 138 at angle connecting horizontal and vertical legs 132a and 132b. The wedge portions serve to reinforce and strengthen the point of connection at the perpendicular protrusions of the corner members 116.

[0034] As illustrated in the exemplary embodiments shown in FIGS. 1, 5 and 6A- 6C, the frame 102 includes twelve frame members 104, which extend between the interior of the corner members 116 to provide the top, bottom, and sides of the frame structure. In various exemplary embodiments, such as depicted in FIGS. 5 and 6A- 6C, the frame members 104 are composed of tubular lengths of material cut to any desired length and having a rectangular cross-section profile.

[0035] Each frame member is formed of an equilateral rectangular rod of selected length having two end faces 142 and four side faces 144 of selected width that form the rectangular structure. The frame member 104 further includes an EMI/RFI suppression lip 146 integrally formed with the rod, and is apertured with mounting holes 148 with staggered spacing, which will be further described below.

[0036] FIGS. 6A-6C depict frame member 104 having the same configuration of an elongated profile, preferably, made of extruded aluminum, but cut at intervals having different lengths to provide the width (FIG. 6A), height (FIG. 6B) and length (FIG. 6C) to form frame 102.

[0037] By extruding rods of varying lengths, the frame member 104 and corner member 116 design permits easy construction of the framework system 100 in many different sizes of different dimensions. Thus, a framework system can be configured having several differing interchangeable frame members with differing lengths. The same frame member can be used to construct various configured framework systems by selecting the appropriate length of the frame member.

[0038] In lieu of using extruded aluminum, in certain applications, the frame members and/or corner members may also be made of stainless steel, copper or other ferrous or non-ferrous materials. The frame members and/or corner members may also be a plastic material or other composite materials. The frame members and/or comer members may also be made of combination of any or all of the mentioned materials.

[0039] In various embodiments as illustrated in FIGS. 5 and 6A-6C, the two end faces 142 of each frame member 104, which is configured to define a rectangular rod in this example, may be constructed having a double angle cut end having a leading edge 150 and a trailing edge 152.

[0040] As shown in FIG. 6A, the angle of cut of the leading edge 150 of the rectangular rod is angled at an acute angle, for example, approximately 45 degree in a direction relative to the trailing edge 152. The double angle cut ends are used to make an angled connection 108 (FIG. 1) between the frame members 104 and the comer members 116. The angle of cut of the leading and trailing edges 150, 152 of the frame member 104 serves to taper the end portions 142 of the frame member into the corner member 116.

[0041] According to the present disclosure, in some embodiments, the frame member may be formed having a double angle cut end positioned at both ends 142. In other embodiments, the frame member may be formed having a single double angle cut end.

[0042] In a comparison of the corners at which three framing members meet in the present disclosure with conventional methods, conventional techniques typically connect two of the members at a 45 degree angle. The third member is connected into the corner by butting the two 45 degree-connected members with an additional 45 degree cut end of the third member which forms a three plane 90 degree corner.

[0043] It should be understood that the frame members 104, having a substantially rectangular cross-section, are for purposes of illustration only, and do not limit the present invention. Those having ordinary skill in the art would appreciate that a variety of geometric structures having differing configurations may be substituted for or used in conjunctions with the rectangular cross-section. The frame members may be defined having a cross-section other than rectangular, which may include for example, a hexagon, a square, a triangle, an oval, a semi-circular, a circular rod having at least one double angle cut end, or other suitable configurations.

[0044] As shown in FIG. 5 and 6A-6C, each frame member 104 may include a suppression lip 146 to direct the electromagnetic waves generated by the enclosed electronic device. In the embodiments shown in FIGS. 5 and 6A-6C, frame member 104 is constructed having a profile center line (CL) extending in the center between two opposing side faces 144. [0045] The EMI/RFI suppression lip 146 is positioned at the center line CL of the joining edge of the two opposing side faces 144 and extends partially along the center line CL. Preferably, the frame member 104 and EMI/RFI suppression lip 146 are formed as a unitary extrusion part, which provides several advantages to this embodiment,

[0046] Among these advantages is reduced cost resulting from the EMI/RFI suppression lip 146 being integral with the rod frame member 104. According!)', there are no inventory and additional labor costs associated with handling extraneous suppression devices. However, depending upon the applications, in some embodiments, the EMI/RFI suppression lip 146 can be a separate piece mounted to the frame member,

[0047] EMI RFI suppression lip 146 is formed along the joining edge to suppress EMI/RFI emissions. The EMI/RFI suppression lip 146 shields the joining edge against the passage of R F waves through the joining edge. The lip 146 may include a raised portion to help direct the electromagnetic waves away from the joining edge. For example, to help block electromagnetic waves from passing through the joining edge, each raised lip 146 may extend substantially along a portion of the joining edge excluding the portion connected within the corner member 116.

[0048] The EMI/RFI suppression lip 146 prevents electromagnetic fields generated by the electronic device from propagating and interfering with other electrical equipment operating in the vicinity. The lip 146 is made of a metallic material that serves as an RFI and/or EMI shield. In this embodiment, the EM I/RFI suppression lip 146 is made of an electrically conductive metal, such as aluminum. [0049] In other embodiments, electrically conductive material such as silver, copper, aluminum, iron, palladium, tin oxide, indium oxide, silicon carbide, zirconium carbide, titanium carbide, graphite, nickel, or a combination thereof may be used to make the suppression lip.

[0050] In still other embodiments, the lip 146 may be coated with a conductive material on its surface, and the conductive material may include silver, copper, aluminum, iron, palladium, tin oxide, indium oxide, silicon carbide, zirconium carbide, titanium carbide, graphite, nickel, or a combination thereof.

[0051] Frame members 104 also include other EMI/RFI suppression characteristics, such as the staggered arrangement of mounting holes (i.e., bores) 148, shown in FIGS. 5 and 6A-6C. The mounting holes 148 are staggered on opposite sides of the edge where two side faces 144 meet each other. The holes 148 depict an alternating pattern such that the holes are offset 90 degrees relative to an adjacent hole. The side faces 144 are provided with mounting holes 148 alternately spaced along the frame member 104 to limit the size of aperture openings, thus raising the frequency of RF signal required before allowing unwanted emissions. These openings can radiate EMI and RFI and by increasing the number of contact points extending across a span of area reduces this unwanted emission.

[0052] To provide effective RFI/EMI suppression, the size and spacing of the apertures can be configured to optimize the suppression of a particular frequency. Generally, the higher the frequency, the closer together the spacing should be. For example, in various embodiments of the present teachings, the screw spacing is designed to suppress approximately 1 GHz. In other embodiments, the spacing between the screws can be further reduced to suppress an even higher frequency, for example, in the range of 2.6 - 3.125 GHz. Accordingly, the apertures of the mounting holes 148 are appropriately spaced, sized and shaped so as to prevent or mitigate the escape of undesirable EMI and RFI. The staggered holes provide similar RFI suppression on each perpendicular plane.

[0053] In assembling the frame 102 structure, the twelve frame members 104 are connected by corner members 116, as shown in FIGS. 1-2. This is achieved by inserting frame members 104 into the space defined by the perpendicular protrusions 126a, 126b, 126c, respectively, such that the EMI/RFI suppression lips 146 extend outwardly along the edge of the frame 102, as shown in FIG. 2, to suppress the passage of EM and RF waves.

[0054] Each frame member 104 can be securely interlocked with the corner members 116 by fastening devices such as screws 134 received into openings 136. At the corners, the corner members 116 and the fastening devices interlocks the horizontal, vertical, and length frame members 104 in such a manner that they serve to attach and hold the frame members rigidly together. The frame members 104 are held in each corner member 116 to form a trihedral arrangement. This arrangement produces a sturdy frame structure having an aesthetically pleasing appearance.

[0055] As a matter of design choice or application, one or more panels may be attached to the frame 102. As depicted in the exemplary embodiments in FIGS. 1-2, when twelve four frame members 104 are each interlocked with respective corner members 116, a framework system 100 is provided for reception and mounting of the end, top, bottom and side panels 112, 114, and 124, respectively.

[0056] The framework system 100 thus described has many advantages. The construction of the frame 102 or chassis can be easily modified for custom applications while allowing for standardization of a product. By varying the length of the frame member, the frame members 104 can be selected from a number of standard modules and assembled to provide an apparatus having a selected desired configuration, without fabricating separate and different sized and shaped frame members.

[0057] Thus, the frame structure provides an ease of assembly and interchangeable simple parts that can configured into both a large or small structure. The embodiments provide a means of using the same frame member construction for several different applications and size requirements, enabling the user to customize the framework system to the particular requirements at substantial savings in manufacturing tooling and inventory expense.

[0058] The framework system also facilitates EMI/RFI suppression. In the described exemplary embodiments, a conductive material, such as an extruded aluminum rectangular rod, configured to form the frame member having a staggered- spaced hole arrangement, provides EMI/RFI suppression. An EMI/RFI suppression lip integrally formed along the frame member also supplies an added security for RFI suppression. In addition, the hole locations on the frame member enable the frame member to be used in multiple positions within the system - also minimizing the number of pieces required to build the framework.

[0059] Particular hole patterns, discussed above, allow for outside panels to be designed for symmetry and commonality to minimize the number of panels required to be used in the system. The location and the number of fastening points also provide rigidity and ruggedness to the system even with the panels attached. [0060] Additionally, the ability to separately add individual side, end, top, and/or bottom plates, the system is very extensible such that it is capable of being extended using the same frame structure, while merely changing the length, width and/or height of the frame member. This feature also provides a pliant system, which is easily altered or modified to fit the desired size and application.

[0061] Furthermore, the design of the double angle cut ends on the frame members in conjunction with the corner members enables respective height, width and length frame members to interlock within the corner members to construct a rugged joint capable of withstanding harsh applications.

[0062] In some embodiments, instead of being positioned externally to the frame as an outside corner member 116 illustrated in FIGS.1-3, the three frame members may be joined together such that the corner members may be situated within the juncture of the three members. Thus, the corner member may be attached to the frame structure as an inside corner member 160 as shown in FIG. 7. The double cut ends on the frame members allow for a three plane 90 degree corner to be formed.

[0063] Those skilled in the art will also appreciate that various adaptations and modifications of the preferred and alternative embodiments described above can be configured without departing from the scope and spirit of the disclosure. Therefore, it is to be understood that, within the scope of the appended claims, the disclosure may be practiced other than as specifically described herein.

Claims

IN THE CLAIMS: We claim:

1. A frame structure comprising: a corner member comprising three mutually perpendicular protrusions, each perpendicular protrusions having a substantially open cross section; and two or more profile members, each having at least one double angle cut end arranged to fit within and attach to respective perpendicular protrusions, the double angle cut ends being joinable to form an angled connection within the corner member.

2. The frame structure according to claim 1 , wherein the corner member comprises an outside corner configured to attach externally to the frame structure.

3. The frame structure according to claim 1 , wherein the corner member comprises an inside corner configured to attach internally to the frame structure.

4. The frame structure according to claim 1, wherein each double angle cut end comprises a tapered end extending from a leading edge to a trailing edge.

5. The frame structure according to claim 1, wherein each perpendicular protrusion comprises two corner forming walls disposed at 90 degrees relative to each other; each corner forming wall defining a horizontal leg and a vertical leg; and a wedge portion extending between the horizontal leg and the vertical leg.

6. The frame structure according to claim 1, wherein at least one profile member includes an electromagnetic interference (EMI)/radio frequency interference (RFI) suppression lip configured to suppress electromagnetic energy emissions.

7. The frame structure according to claim 6, wherein the EMI/RFI suppression lip extends substantially along a center line of the at least one profile member.

8. The frame structure according to claim 6, wherein the EMI/RFI suppression lip comprises an electrically conductive material.

9. The frame structure according to claim 1, wherein at least one profile member defines a rectangular member comprising a plurality of staggered mounting holes, wherein each mounting hole is positioned in an offset position 90 degrees relative to an adjacent mounting hole located on an adjacent side of the rectangular member.

10. The frame structure according to claim 1, wherein at least one profile member has a rectangular cross-section.

11. The frame structure according to claim 1 , wherein at least one profile member has four side faces defining a rectangular cross-section; an EMI/RFI suppression lip extending along a joining edge connecting two of the side faces of the profile member; and a plurality of holes provided on the three side faces in a staggered arrangement such that each hole alternates at an offset position 90 degrees relative to an adjacent hole positioned on an adjacent side face.

12. The frame structure according to claim 1 , wherein the corner member and the profile members are extruded from aluminum.

13. A frame structure comprising: a corner member comprising three mutually perpendicular protrusions, each perpendicular protrusions having a substantially open cross section; and three profile members, each profile member having at least one double angle cut end arranged to fit within and attach to respective perpendicular protrusions; a first electromagnetic interference (EMI)/radio frequency interference (RFI) suppression component positioned substantially along a length of at least one of the profile members; and a second EMI/RFI suppression component provided within side faces of the at least one profile member to form an alternating pattern between adjacent side faces of the at least one profile member.

14. The frame structure according to claim 13, wherein the first EMI/RFI suppression component comprises a raised lip extending substantially along a joining edge that connects two sides of the at least one profile member.

15. The frame structure according to claim 13, wherein the second EMI/RFI suppression component comprises a plurality of mounting holes spaced in a pattern that alternates between the adjacent side faces of the at least one profile member to form a staggered mounting holes configuration.

16. The frame structure according to claim 13, wherein the at least one profile member has a rectangular cross section.

17. The frame structure according to claim 13, wherein the at least one double angle cut end comprises a tapered end extending from a leading edge to a trailing edge.

18. The frame structure according to claim 13, wherein each perpendicular protrusion comprises two corner forming walls disposed at 90 degrees relative to each other; each corner forming wall defining a horizontal leg and a vertical leg; and a wedge portion extending between the horizontal leg and the vertical leg.

19. A modular frame assembly comprising: a plurality of corner members, wherein at least one corner member comprises three mutually perpendicular protrusions, each perpendicular protrusions having a substantially open cross section; and a plurality of frame members, wherein at least three profile members comprise at least one double angle cut end and the at least three profile members are arranged to fit within and attach to respective perpendicular protrusions, and wherein the at least three profiles members are configured having identical profile configurations and different lengths such that the at least three profile members are interchangeable to form a variety of frame assemblies having different configurations.

20. The modular frame assembly according to claim 19, further comprising a first electromagnetic interference (EMI)/radio frequency interference (RFI) suppression component positioned substantially along a length of the at least three profile members; and a second EMI/RFI suppression component provided within side faces of the at least three profile members to form an alternating pattern in the adjacent side faces of the at least three profile members.