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Publication numberUS2317813 A
Publication typeGrant
Publication dateApr 27, 1943
Filing dateFeb 28, 1940
Priority dateFeb 28, 1940
Publication numberUS 2317813 A, US 2317813A, US-A-2317813, US2317813 A, US2317813A
InventorsSchoenborn Ferdinand Julius W
Original AssigneeRca Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Shielding
US 2317813 A
Abstract  available in
Images(1)
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Claims  available in
Description  (OCR text may contain errors)

Patented Apr. 27, 1943 UNITED SHIELDI'NG Ferdinand Julius W. Schoenborn. lliverhead,

N. Y., assignor to Radio Corporation of America, a corporation of Delaware Application February 28, 1940, Serial No. 321,220

6 Claims.

This invention relates to a new and useful shielding method and devices to obtain good electrical shielding and conductivity between the metallic surfaces which are normally not tight fitting.

An object of this invention is to provide an improved shield which when employed in an ultra high frequency receiver or a diversity radio receiver circuit will result in substantially no electrical leakage which is usually caused by insuflicient contacts where shields Join, and the elimination of circuit noise caused by imperfect contact.

Another object of this invention is to provide an improved shield member in which the teeth are slanted in opposing directions and fashioned to result in a non-creeping metallic electrical shield which causes no misalignment of assembled parts.

/A feature of this invention is the novel method cutting multiple teeth in both metal surfaces of the shielding parts when pressure is applied to such surfaces.

Previous methods known in the prior art included the use of flat springs, wire gauze gaskets, or round cans.

Briefly, the method of this invention employs the use of a thin sheet of spring tempered metal having high electrical conductivity and will be more completely understood by the accompanying drawing, in which:

Fig. 1 shows a plan view of a simple contact plate;

Fig. 2 is a side elevation of Fig. 1;

Fig. 3 is an enlarged view of Fig. 1;

Fig. 4 is an enlarged view of Fig. 2; and

Fig. 5 is a section through a shielding can employing this invention.

Referring now in detail to the drawing, it will be noted that slots are out on all sides of the metal sheet I which is preferably beryllium copper having high electrical conductivity. The thickness of the metal should be about .010 of an inch to .020 of an inch thick. A plurality of slots 2 are cut on all sides of the sheet to form teeth which are located at intervals of /3 or more since the number of teeth used are in direct proportion to the shielding quality obtained. After the slots are cut, the teeth are given a twist to an angle of about 30 in the same general direction starting at the longitudinal and transverse axis or center of a given side of the sheet and in an opposite direction for the remaining half of the sheet. This novel arrangement of twisting the teeth results in an improved noncreeping metallic electrical shield and therefore causes no misalignment of the assembled parts.

The twisted teeth extend approximately .050 of an inch beyond the solid surface of sheet I.

By alternating the direction of the twist of the teeth, as described above, the sheet or electrical shield member I will not creep in any direction as pressure is applied to bring the surfaces of two or more metallic parts toge her.

The sheets are bound together by any suitable means such as having a plurality of apertures I therein in which bolts, screws, rivets or the like may pass.

Fig. 5 shows the same general method applied to a shielding can 4 for enclosing and shielding a coil 5 and/or condenser unit 8. The can is closed by a cover I secured to a marginal end 8 by binding means such as screws 12 passing through apertures in cover I, also the apertures 3 in the electrical shield member I to the can corner posts 10.

Although only a few embodiments of this invention are shown, it should be understood that the invention is not to be limited precisely as described.

What is claimed is:

1. A non-creeping electrical shielding member comprising a spring tempered metallic sheet fabricated in such a fashion as to provide multiple marginal teeth which are bent to slant in an opposing direction each side of the center of said.

sheet and along all contact edges for insertion between butt joints of radio frequency shielding members thereby providing a means for good electrical leakage-free contact joints due to the biting action of the slanted teeth when said members are assembled.

2. A non-creeping electrical shielding member comprising a spring tempered metallic sheet fabricated to provide marginal teeth out and bent to produce a cutting action on contact surfaces of assembled metallic shielding devices, said teeth bent to slant in an opposing direction each side of the center of said sheet to result in a noncreeplng metallic member which causes no misalignment of assembled parts.

3. A metallic electrical shielding device comprising a metallic casing, a cover for said casing, a non-creeping spring tempered metallic sheet having a plurality of slots bent in opposing directions each side of the longitudinal and transverse axis of said sheet forming teeth interposed between the upper open end of said casing and the underside of said cover, and means within 4. A metallic electrical shielding device comprising a metallic casing, a cover for said casing, a non-creeping spring tempered metallic sheet having a plurality of slots bent in opposing directions each side of the longitudinal and transverse axis of said sheet i'orming teeth interposed between the open end of said casing and the underside of said cover, and means located at each corner of said casing for binding said sheet and cover thereto.

5. A non-creeping electrical shielding member comprising a spring tempered sheet having high electrical conductivity, said sheet including a plurality of slots cuton its marginal zone and forming teeth thereon, said teeth which are located on one side of the longitudinal and transverse 10 eluding a plurality of slots cut on its marginal zone axis being twisted in one diretcion and the teeth on the other side of the longitudinal and transverse axis being bent in the other direction, and means binding said a sheet to another metallic member.

G QSnon-creeping electrical shielding member comp ing a spring tempered rectilinear sheet having high electrical conductivity, said sheet having an aperture located in each corner and inand forming teeth thereon, said teeth which are located on one side of the longitudinal and trans- .verse axis being twisted in one direction and the teeth on the other side or the longitudinal and transverse axis being bent in the other direction, and means passing through said apertures for binding said sheet to another metallic member. FERDINAND JULIUS W. SCHOENBORN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2442274 *Jun 16, 1944May 25, 1948English Electric Co LtdTransformer
US2604507 *Aug 9, 1945Jul 22, 1952Bendix Aviat CorpShielding closure means
US2629764 *Jun 7, 1949Feb 24, 1953Sylvania Electric ProdAutomobile radio cabinet with cover contact clips
US3181069 *Jun 22, 1960Apr 27, 1965Standard Coil Prod Co IncUhf television tuner
US3881799 *Sep 11, 1972May 6, 1975George H ElliottResilient multi-micro point metallic junction
US4384165 *Sep 14, 1981May 17, 1983Motorola, Inc.Radio frequency shield with force multiplier interconnection fingers for an electromagnetic gasket
US4396795 *Jun 30, 1981Aug 2, 1983Rca CorporationNon-contacting RF shielding gasket with molded stub members
US4399316 *Jun 30, 1981Aug 16, 1983Rca CorporationNon-contacting RF shielding device
US4717791 *Jul 9, 1986Jan 5, 1988Tektronix, Inc.Shield structure for limiting transmission of electromagnetic radiation
US4810830 *Sep 8, 1987Mar 7, 1989Uro Denshin Kogyo Kabushiki KaishaShield case for television signal branch distributor
US5049701 *Sep 28, 1989Sep 17, 1991Stratus Computer, Inc.EMI cabinet with improved interference suppression
US5204496 *Apr 1, 1992Apr 20, 1993Digital Equipment CorporationEMI shielding gasket
US5524908 *Sep 14, 1994Jun 11, 1996W. L. Gore & AssociatesMulti-layer EMI/RFI gasket shield
US6259609Mar 15, 2000Jul 10, 2001Arthur A. KurzShielding contactor construction
US6607308Aug 22, 2001Aug 19, 2003E20 Communications, Inc.Fiber-optic modules with shielded housing/covers having mixed finger types
US6659655Feb 12, 2001Dec 9, 2003E20 Communications, Inc.Fiber-optic modules with housing/shielding
US6874953Jul 11, 2003Apr 5, 2005Jds Uniphase CorporationMethods and apparatus for fiber-optic modules with shielded housings/covers with fingers
US20030152331 *Dec 31, 2002Aug 14, 2003Edwin DairMethods and apparatus for fiber-optic modules with shielded housing/covers having mixed finger types
US20030152339 *Dec 31, 2002Aug 14, 2003Edwin DairMethods and apparatus for fiber-optic modules with shielded housing/covers having a front portion and a back portion
US20040037517 *Jul 11, 2003Feb 26, 2004Edwin DairMethods and apparatus for fiber-optic modules with shielded housings/covers with fingers
DE963620C *Jul 16, 1953May 9, 1957Telefunken GmbhFederband, besonders fuer Abschirmgehaeuse von Hochfrequenzgeraeten
DE3224221A1 *Jun 29, 1982Jan 13, 1983Rca CorpBeruehrungsfreie hf-abschirmung, insbesondere abschirmdichtung mit umgefalteten laschen
WO1983001174A1 *Aug 30, 1982Mar 31, 1983Motorola IncRadio frequency shield with force multiplier interconnection fingers for an electromagnetic gasket
Classifications
U.S. Classification174/369, 455/347, 455/300
International ClassificationH05K9/00
Cooperative ClassificationH05K9/0049
European ClassificationH05K9/00B9