SE1950559A1 - Feed-through - Google Patents
Feed-throughInfo
- Publication number
- SE1950559A1 SE1950559A1 SE1950559A SE1950559A SE1950559A1 SE 1950559 A1 SE1950559 A1 SE 1950559A1 SE 1950559 A SE1950559 A SE 1950559A SE 1950559 A SE1950559 A SE 1950559A SE 1950559 A1 SE1950559 A1 SE 1950559A1
- Authority
- SE
- Sweden
- Prior art keywords
- housing
- plug member
- feed
- attachment means
- wall
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/42—Coupling light guides with opto-electronic elements
- G02B6/4201—Packages, e.g. shape, construction, internal or external details
- G02B6/4248—Feed-through connections for the hermetical passage of fibres through a package wall
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/42—Coupling light guides with opto-electronic elements
- G02B6/4201—Packages, e.g. shape, construction, internal or external details
- G02B6/4274—Electrical aspects
- G02B6/4277—Protection against electromagnetic interference [EMI], e.g. shielding means
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B17/00—Insulators or insulating bodies characterised by their form
- H01B17/26—Lead-in insulators; Lead-through insulators
- H01B17/30—Sealing
- H01B17/303—Sealing of leads to lead-through insulators
- H01B17/308—Sealing of leads to lead-through insulators by compressing packing material
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G15/00—Cable fittings
- H02G15/013—Sealing means for cable inlets
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G3/00—Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
- H02G3/02—Details
- H02G3/08—Distribution boxes; Connection or junction boxes
- H02G3/088—Dustproof, splashproof, drip-proof, waterproof, or flameproof casings or inlets
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G3/00—Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
- H02G3/22—Installations of cables or lines through walls, floors or ceilings, e.g. into buildings
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Electromagnetism (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
A revolver-type feed-through (2) for TEMPEST -grade electromagnetic shielding where one or more non-electric signal leads (18) pass through a wall (16) of a cabinet or other enclosure comprises a housing (4) having a conical inner surface (8), the housing being attachable to the wall through a first attachment means (10); and a plug member (6) having a conical outer surface (12) matching the conical inner surface (8) of the housing (4), the plug member being attachable to the housing (4) through a second attachment means (14), wherein the conical inner surface (8) of the housing (4) and/or the conical outer surface (12) of the plug member have recesses (20) forming, when the plug member (6) is attached to the housing (4), a plurality of waveguides (22), the feed-through (2) further comprising a weather seal frame (106) comprising an upper part (106b) and a lower part (106a) adapted to fit around and seal against the housing; and a plurality of resilient sealing blocks (104) adapted to be compressed between the upper part (106b) and the lower part (106a) of the weather seal frame (106), sealing around the one or more signal leads (18).
Description
FEED-THROUGH Field of the invention The present inventive concept relates to a revolver-type feed-throughfor TEMPEST-grade electromagnetic shielding where one or more non-electric signal leads pass through a wall of a cabinet or other enclosure.
BackgroundSuch a feed-through can be used to prevent emission of electromagnetic waves, for example to avoid electromagnetic interference orthe leakage of critical information from electronic equipment, such as anetwork switch or server, placed in a cabinet or enclosure. For thisapplication, standards, usually referred to using the term “TEMPEST”, areestablished that require attenuation up to the order of 100 dB at frequenciesup to 10 GHz at the feed-through.
To achieve such attenuation characteristics, such a feed-throughs maycomprise one or more waveguides operating below cut-off frequency.
Revolver-type feed-throughs, wherein a plurality of waveguides aredistributed around the interface between a housing and a plug memberpushable into the housing, are known in the prior art. Examples of suchfeedthroughs are disclosed in documents US4849723 andUS20170090120A1 _ There is always a need to improve such feed-throughs.
SummaryAccording to the present inventive concept, and, according to a first aspect, there is provided a revolver-type feed-through for TEMPEST-gradeelectromagnetic shielding where one or more non-electric signal leads passthrough a wall of a cabinet or other enclosure, comprising a housing having aconical inner surface, the housing being attachable to the wall through a firstattachment means; and a plug member having a conical outer surfacematching the conical inner surface of the housing, the plug member being attachable to the housing through a second attachment means, wherein theconical inner surface of the housing and/or the conical outer surface of theplug member have recesses forming, when the plug member is attached tothe housing, a plurality of waveguides. Each of the first attachment meansand the second attachment means are operable by one or more operatingmembers located, with the feed-through in installed position, exclusively onone side of the wall, so that the first attachment means and the secondattachment means are exclusively operable from that one side of the wall.
Typically, the said one side of the wall is the inside of the cabinet ofenclosure. ln this way, a tamper- and breakin-proof feed-through is provided.Using such a feed-through eliminates or mitigates the need for additionalsecurity measures external to the feed-through, saving space and cost.
Preferably, the first attachment means and the second attachmentmeans are removable. This allows for flexibility of installation.
A recess of the conical outer surface may have a slot for a cover,wherein, with the plug member attached to the housing and the coverinstalled in the slot, the housing covers the slot, preventing the cover frombeing removed from the slot. ln typical use, a waveguide will be covered by aslot if it is unused, i.e., no signal passes through it. This provides additionalsecurity and tamper-proofing, since it eliminates the possibility of tamperingwith the operating members through the waveguides.
The housing may have a non-circular cross-section, which, with thehousing in installed position at the wall, may fit into a corresponding non-circular opening in the wall, preventing the housing from rotating with respectto the wall. Alternatively, or additionally, the one or more operating means ofthe first attachment means may be operable without rotating the housing. Thisprovides additional security and tamper-proofing, since it eliminates thepossibility of tampering with or loosening the housing from the wall by rotatingit.
The first attachment means may comprise an outer thread on thehousing and a nut, comprising the operating member, having an inner threadmatching the outer thread of the housing. This provides a simple yet securemechanism for attaching the housing to the wall.
The second attachment means may, in a first alternative, comprise abolt provided with an outer thread; a threaded bore in the plug member withan opening located, with the feed-through in installed position, on said oneside of said wall, the threaded bore matching the outer thread of the bolt; andan elongated crossbar; wherein the bolt, with the plug member attached tosaid housing, pulls against said plug member through the threaded bore andpushes against the housing through the crossbar. This provides a simple yetreliable mechanism for attaching the plug member to the housing.
Using an elongated crossbar, which may fit into a pair of slots on thehousing, instead of a more elaborate plate structure which must have largerecesses matching the waveguides, simplifies manufacturing while stillproviding a second attachment means with higher strength and reliability thatalso is easier to install. ln a second alternative, the second attachment means may comprise atransversal slot through the plug member; a pair of openings in the housing,matching the transversal slot; and a locking rod provided with a convexsurface, wherein the locking rod, with the plug member attached to thehousing, extends through the transversal slot and the pair of openings and ata first end is pivoted at a pivot point fixed in position with respect to thehousing and at a second end is pushed so that the convex surface abutsagainst an inner surface of the transversal slot, pushing the plug member in adirection into the housing.
This provides a mechanism that is easier to install, yet secure, if spacebehind the feed-through, usually on the inside of the cabinet or enclosure, istight. Further, the locking rod provides a lever arm which simplifies removal ofthe second attachment means.
The locking rod may have a second convex surface, opposite theconvex surface, where, during removal of the second attachment means, thesecond convex surface abuts a second inner surface of the transversal slot.This aids removal of the second attachment means using the locking rod as alever arm.
The pivot point and the pushing may be provided by a framearrangement mountable around the housing. The frame, in installed position,may abut against a shoulder of the housing.
Alternatively again, the feed-through may comprise second attachmentmeans according to both the first alternative and according to the secondalternative above. The alternative actually used at the point of installation maythen be selected during installation of the feed-through, increasing flexibility.For example, the components may be provided as a kit.
The feed-through may further comprise a weather seal frame,comprising an upper part and a lower part adapted to fit around the housing;and a plurality of resilient sealing blocks adapted to be compressed betweenthe upper part and the lower part of said weather seal, sealing around the oneor more signal leads. Advantages and embodiments are identical to thosedescribed below in conjunction with the sixth aspect.
The plurality of waveguides may comprise four waveguides arranged ina rectangular pattern. This allows the waveguides to line up with the resilientblocks of the weather seal, allowing such a seal to be used together with therevolver-type feed-through.
The said plug member may comprise a transversally extending pinmatching a transversal slot in the housing. During insertion of the plugmember into the housing, the slots will rotationally guide the plug member.Further, with the plug member inserted into and attached to the housing, theslot and pin will prevent the plug member from rotating with respect to thehousing. This provides a simple and robust mechanism that simplifiesinstallation, as the plug member is ensured to always have the correctrotational configuration with respect to the housing.
According to a second aspect, there is provided a system, comprisingthe feed-through according to the first aspect, one or more of signal leads,and a cabinet or enclosure.
Advantages and embodiments of this second aspect are at least thesame as and/or compatible with those described above in conjunction withthe first aspect.
According to a third aspect, there is provided a method of installing arevolver-type feed-through for TEMPEST-grade electromagnetic shieldingthrough a wall of a cabinet or other enclosure, comprising: attaching ahousing to the wall through a first attachment means, the housing having aconica| inner surface; pu||ing one or more non-electric signal leads throughthe housing; attaching a plug member to the housing, an outer conica| surfaceof said plug member matching the conica| inner surface of the housing, theconica| inner surface and/or the conica| outer surface having recessesforming a plurality of waveguides enclosing said one or more signal leads;said method being characterized by said first attachment means and saidsecond attachment means being exclusively operated from one side of saidwall.
Advantages and embodiments of this third aspect are at least the sameas and/or compatible with those described above in conjunction with the firstaspect.
According to a fourth aspect, there is provided a revolver-type feed-through for TEMPEST-grade electromagnetic shielding where one or morenon-electric signal leads pass through a wall of a cabinet or other enclosure,comprising a housing having a conica| inner surface, the housing beingattachable to the wall through a first attachment means; and a plug memberhaving a conica| outer surface matching the conica| inner surface of thehousing, the plug member being attachable to the housing through a secondattachment means, wherein the conica| inner surface of the housing and/orthe conica| outer surface of the plug member have recesses forming, whenthe plug member is attached to said housing, a plurality of waveguides, thefeed-through being characterized by further comprising a weather seal framecomprising an upper part and a lower part adapted to fit around and sealagainst the housing; and a plurality of resilient sealing blocks adapted to becompressed between the upper part and the lower part of said weather seal,sealing around the one or more signal leads.
With weather seal should be understood a seal sealing against one ormore of, but not limited to, weather, moist, dirt, oil, splashing water, whichmay be fresh or salt water, or similar.
This allows weather sealing to be provided directly by the feed-through,eliminating the need for additional measures to provide weather sealing, forexample the need to place the cabinet or enclosure in a weather-sealedroom. This saves space. This, for example, is useful in marine applications.
The upper part and the lower part may be identical in design, whichsimplifies manufacturing and installation.
Advantages and embodiments described above in conjunction with thefirst aspect are compatible with this fourth aspect.
According to a fifth aspect, there is provided use of a revolver-typefeed-through for TEMPEST-grade electromagnetic shielding where one ormore non-electric signal leads pass through a wall of a cabinet or otherenclosure, the feed-through comprising: a housing having a conical innersurface, the housing being attachable to the wall through a first attachmentmeans; and a plug member having a conical outer surface matching theconical inner surface of the housing, the plug member being attachable to thehousing through a second attachment means, wherein the conical innersurface of the housing and/or the conical outer surface of the plug memberhave recesses forming, when the plug member is attached to the housing, aplurality of waveguides, in combination with a weather seal comprising aweather seal frame comprising an upper part and a lower part adapted to fitaround and seal against the housing; and a plurality of resilient sealing blocksadapted to be compressed between the upper part and the lower part of theweather seal frame, sealing around the one or more signal leads.
Advantages and embodiments of this fifth aspect are at least the sameas and/or compatible with those described above fourth aspect. Advantagesand embodiments described above in conjunction with the first aspect arecompatible with this fifth aspect.
Brief description of the drawinqs The above, as well as additional objects, features and advantages ofthe present inventive concept, will be better understood through the followingillustrative and non-limiting detailed description of preferred embodiments,with reference to the appended drawings, where the same referencenumerals will be used for similar elements, wherein: Figs 1a and 1b are exploded views, from two different respectiveangles, of a revolver-type feedthrough; Figs 2a, 2b; 3; 4, and 5a, 5b, 5c, 5d show a typical assembly sequenceof the feed-through, wherein Figs 2a, 2b; 3; 4; and 5a, 5b are perspectiveviews and 5c, 5d are cross-sectional views; Figs 6; 7; 8; 9a, 9b; and 10 show a typical assembly sequence of analternative second attachment means of the feed-through, wherein Figs 6; 7;8; 9a are perspective views and Figs 9b and 10 are cross-sectional views; Fig. 11 is a cross-sectional view showing removal of the alternativesecond attachment means.
Figs 12, 13, 14, 15, and 16 are perspective views showing assembly ofan optional weather seal for use with the feedthrough; Fig. 17 schematically illustrates a protected cabinet or other enclosure;and Fig. 18 schematically illustrates a waveguide operating below-cutofffrequency.
Detailed descriptionFig. 17 illustrates a protected cabinet or other enclosure 201, which is a context where a feed-through 2 (cf. Figs 1a and 1b) according to thepresent disclosure can be used. Such a cabinet or other enclosure can beused in a sensitive environment where processing devices 203 in the cabinet201, such as servers, electronically process unencrypted or encryptedsensitive information. The cabinet 201, made from an electrically contuctivematerial, which may be thick sheet metal, functions as a Faraday cage,containing within its enclosure any electromagnetic radiation from theprocessing devices 203, thereby preventing the leakage of sensitive information. The processing devices 203 communicate with nodes 213outside the cabinet 201 via non-electric signal leads 205, such as opticalfibers, which are terminated by means of connectors 207, 209 at each if theirends. The signal-leads must be non-electric in order not to spoil thefunctioning of the shielding, as an electric signal lead would act as anantenna, spoiling the shielding of the inside of the cabinet or enclosure. Thesignal leads may convey less sensitive information or the information carriedby them may be encrypted. Furthermore, the conveyed optical signals assuch usually give negligible leaked radiation, preventing interception of suchsignals, unless the fibers are tampered with.
The feed-through where the optical fibers extend out of the cabinet 201requires special attention so that electromagnetic radiation does not escapethe cabinet, risking interception by a third party nearby. ln addition to the shielding situation described above, the feed-throughmay be useful in other situations where considerable attenuation at aconnection into a Faraday cage is needed. For instance, as the effectprovided is more or less reciprocal, the feed-through could protect sensitiveequipment in a cabinet from external electromagnetic interference, such aselectromagnetic pulses with high energy. Further, a shielded room used forsensitive measurements could be protected from external electromagneticinterference, etc.
Additionally, the cabinet or enclosure 201 may be subject torequirements of weather proofing and/or tamper proofing and/or securityagainst break-in. Normally such feed-throughs do not provide suchfunctionality by themselves, requiring such functionality to be providedexternal to the cabinet or enclosure 201, for example by the cabinet orenclosure being located in a secured and/or weather sealed room. With thepresent inventive concept, such functionality may be provided directly by thefeed-through itself. This is particularly advantageous in environments wherespace is at a premium.
As is well known per se, an attenuating feed-through can be obtainedby means of a waveguide below-cutoff, WBCO, of which one example isschematically illustrated in Fig 16. ln this example the waveguide 212, made from a conductive material, has a cavity 214, open at both ends, with acircular cross section with diameter D and a length l. The waveguide extendsthrough a wall in a Faraday cage 201.
Electromagnetic waves can propagate through a waveguide in anumber of different modes, corresponding to different solutions to the Maxwellequations. These modes are distinguished by different configurations of theelectric and magnetic fields. Each of these modes has a cut-off frequency,below which no substantial propagation in that mode is possible. Below thelowest cut-off frequency of all possible modes, no substantial propagation ofelectromagnetic waves is possible at all. lnstead, signals suffer exponentialattenuation. For example, in a circular waveguide, the mode with the lowestcut-off frequency is the TE11 (transverse electric) mode. The cut-off frequencyfc of that mode can be shown to be, to three significant figures, Û.586 17c I D 1 where v is the propagation speed of the waveguide dielectric, i.e., thenon-conductive material forming the bulk of the waveguide cavity. ln air, v isto a good approximation 3><108 m/s. Below this cut-off frequency, over adistance l, an electromagnetic wave with frequency f suffers a totalattenuation of again to three significant figures, 2 A=32.0% 1-
Claims (3)
1. A revolver-type feed-through (2) for TEMPEST-grade electromagneticshielding where one or more non-electric signal leads (18) pass through awall (16) of a cabinet or other enclosure, comprising: a housing (4) having a conical inner surface (8), said housingbeing attachabie to said wall through a first attachment means (10); and a plug member (6) having a conical outer surface (12) matchingsaid conical inner surface (8) of said housing (4), said plug member beingattachabie to said housing (4) through a second attachment means (14), wherein said conical inner surface (8) of said housing (4) and/or said conical outer surface (12) of said plug member have recesses (20) forming,when said plug member (6) is attached to said housing (4), a plurality ofwaveguides (22), said feed-through (2) being characterized by furthercomprising: a weather seal frame (106) comprising an upper part (106b) anda lower part (106a) adapted to fit around and seal against said housing; and a plurality of resilient sealing blocks (104) adapted to becompressed between said upper part (106b) and said lower part (106a) ofsaid weather seal frame (106), sealing around said one or more signalleads (18).
2. The feed-through of claim 1, wherein said plurality of waveguides (22)comprises four waveguides (22) arranged in a rectangular pattern.
3. Use of a revolver-type feed-through (2) for TEMPEST-gradeelectromagnetic shielding where one or more non-electric signal leads (18)pass through a wall (16) of a cabinet or other enclosure, the feed-throughcomprising: a housing (4) having a conical inner surface (8), said housingbeing attachabie to said wall through a first attachment means (10); and a plug member (6) having a conical outer surface (12) matchingsaid conical inner surface (8) of said housing (4), said plug member beingattachabie to said housing (4) through a second attachment means (14), 19 wherein said conical inner surface (8) of said housing (4) and/or saidconical outer surface (12) of said plug member (6) have recesses (20)forming, when said plug member (6) is attached to said housing (4), a pluralityof waveguides (22),in combination with a weather sea| comprising:a weather sea| frame (106) comprising an upper part (106b) anda lower part (106a) adapted to fit around and sea| against said housing (4);anda plurality of resilient sealing blocks (104) adapted to becompressed between said upper part (106b) and said lower part (106a) ofsaid weather sea| frame, sealing around said one or more signal leads (18).
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE1950559A SE543812C2 (en) | 2019-05-09 | 2019-05-09 | Weather-sealed feed-through for electromagnetic shielding |
| US17/609,840 US20220221660A1 (en) | 2019-05-09 | 2020-05-07 | Feed-through |
| EP20727402.8A EP3967117B1 (en) | 2019-05-09 | 2020-05-07 | Feed-through |
| PCT/SE2020/050471 WO2020226564A1 (en) | 2019-05-09 | 2020-05-07 | Feed-through |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE1950559A SE543812C2 (en) | 2019-05-09 | 2019-05-09 | Weather-sealed feed-through for electromagnetic shielding |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| SE1950559A1 true SE1950559A1 (en) | 2020-11-10 |
| SE543812C2 SE543812C2 (en) | 2021-07-27 |
Family
ID=73649973
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| SE1950559A SE543812C2 (en) | 2019-05-09 | 2019-05-09 | Weather-sealed feed-through for electromagnetic shielding |
Country Status (1)
| Country | Link |
|---|---|
| SE (1) | SE543812C2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE2150847A1 (en) * | 2021-06-30 | 2022-12-31 | Roxtec Ab | Transition for optical fibre cable |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5426715A (en) * | 1993-07-23 | 1995-06-20 | Raychem Corporation | Oval port seal and method used for an optical fiber cable closure |
| US6948976B2 (en) * | 2004-03-01 | 2005-09-27 | Andrew Corporation | Cable and apparatus interface environmental seal |
| DE102005062655B3 (en) * | 2005-12-21 | 2007-03-01 | Gk-System Gmbh | Sealing device for encased cables, lines and tubes has at least one limiting surface of module pack receiver formed by separate part-element |
| EP3128353A1 (en) * | 2015-08-07 | 2017-02-08 | CCS Technology Inc. | Cable grommet and fiber optic distribution device |
| US20170090120A1 (en) * | 2015-09-29 | 2017-03-30 | Fiberplex Technologies, LLC | Waveguide filter |
| DE102016102671A1 (en) * | 2016-02-16 | 2017-08-17 | Reichle & De-Massari Ag | Contact housing device, modular system for producing a contact housing device and method for producing a contact housing device using a modular system |
| US10680423B2 (en) * | 2016-11-21 | 2020-06-09 | Icotek Project Gmbh & Co. Kg | Device for introducing a cable into a room |
| DE102017208477A1 (en) * | 2017-05-19 | 2018-11-22 | Icotek Project Gmbh & Co. Kg | Grommet |
-
2019
- 2019-05-09 SE SE1950559A patent/SE543812C2/en unknown
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE2150847A1 (en) * | 2021-06-30 | 2022-12-31 | Roxtec Ab | Transition for optical fibre cable |
| SE544952C2 (en) * | 2021-06-30 | 2023-02-07 | Roxtec Ab | Transition for optical fibre cable |
Also Published As
| Publication number | Publication date |
|---|---|
| SE543812C2 (en) | 2021-07-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3235357B1 (en) | Feed-through | |
| US6713672B1 (en) | Compliant shaped EMI shield | |
| EP0715492B1 (en) | Self-fastening EMI-shielding enclosures | |
| EP2643739B1 (en) | Port for inhibiting electromagnetic radiation | |
| US6566973B2 (en) | EMI enclosure having a waveguide for cables | |
| EP0843512A3 (en) | High frequency emi shield with air flow for electronic device enclosure | |
| US7994434B2 (en) | Electromagnetic interference shielding apparatus and method | |
| EP3430675A1 (en) | Board to board contactless interconnect system | |
| US9093755B2 (en) | Lower power localized distributed radio frequency transmitter | |
| SE1950559A1 (en) | Feed-through | |
| SE1950558A1 (en) | Feed-through | |
| US6474876B1 (en) | Shielded optical fiber adaptor | |
| EP3967117B1 (en) | Feed-through | |
| DE102014117315A1 (en) | Device for transmitting signals from a housing opening of a metallic housing | |
| US6434312B1 (en) | Shield for fiber optic connectors and cables | |
| JPH08125378A (en) | Radio wave dark room arrangement | |
| SE538573C2 (en) | Feed-through | |
| US6229714B1 (en) | Apparatus and method for electromagnetic shielding of equipment cabinets | |
| US5051747A (en) | Interface for cables | |
| US20030099101A1 (en) | Optical network unit with EMI suppression | |
| JPS6032799Y2 (en) | Device housing lid rotation structure | |
| DE10034028C2 (en) | microwave arrangement | |
| US20230318515A1 (en) | Avoiding electromagnetic interference (emi) in electrical equipment and drive systems, e.g. used in radio astronomy | |
| JP3098313B2 (en) | Electromagnetic shielding case | |
| JPH08274487A (en) | Structure for preventing leakage of electromagnetic wave |