Patent Application
20090126987
The present embodiments generally relate to a fold-in braided shield and a method of forming the fold-in braided shield.
Although electromagnetic radiation can be generated from any number of sources, including natural phenomenon like lightning strikes, the emergence of electronic devices, and specifically telecommunication devices, has rapidly increased the amount of electromagnetic radiation propagating through the air. This external electromagnetic radiation can interfere with electronic devices by causing a current to flow through wires and other metallic objects. Since this extraneous current may generate unwanted signals, including a spike in current that can damage electronic components, some treat the rapid increase in electromagnetic radiation as a form of pollution. In addition, electromagnetic energy produced from internal electromagnetic sources, such as high current cables, can also radiate out of the wire and interfere with other electronic devices.
One way to combat these extraneous currents is to protect the wires of electronic devices from external electromagnetic radiation by using a braided metallic shield that covers and extends along the length of the wire. The braided metallic shield also prevents electromagnetic radiation from leaking out of the wire, reducing interference to external devices. A terminal end of the shield may include a solid metal support that is crimped to the shield. When the support is placed inside the shield, the terminal end of the shield is expanded, which separates the wires that form the braid in the shield, creating “holes.” Unfortunately, the “holes” provide a means for electromagnetic radiation to penetrate through the wire and interfere with transmitted signals on the wire. Also, as the terminal end of the shield ages, the wires that make up the shield may begin to unravel, causing additional “holes” in the shield. In addition, the unraveling weakens the crimp to the metal support, resulting in the braid having reduced pull strength. Finally, the terminal end of the shield, as it begins to unravel, can cause galvanic corrosion between the shield and the metal support.
Accordingly, a braid shield is needed that reduces or eliminates the number of holes in the shield to reduce or eliminate electromagnetic radiation into and out of the cable while providing a strong and consistent crimp with the support.
A braided shield includes a housing having an outer layer and a support at least partially disposed in the housing and spaced from the outer layer. The housing further includes an inner layer integrally formed with the outer layer and disposed between the outer layer and the support to establish a dual-layer configuration.
A method of forming the braided shield includes providing a housing having an end portion and defining a longitudinal axis and a passage extending along the longitudinal axis, compressing the end portion transverse to the longitudinal axis, and forcing the end portion into the passage to define the housing having an outer layer and an inner layer integrally formed with the outer layer.
The present embodiments become better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
A braided shield includes a housing having a dual-layer configuration. The housing is formed from a plurality of wires braided together and has an outer layer integrally formed with an inner layer to establish the dual-layer configuration. A support is at least partially disposed in the housing, and the inner layer is disposed between the support and the outer layer. The inner layer and outer layer reduce the amount of electromagnetic radiation that leaks into or out of the housing by reducing the number of holes in the housing. Forming the braided shield includes providing the housing, which defines a longitudinal axis and a passage extending along the longitudinal axis. The housing has an end portion, and the end portion is compressed transverse to the longitudinal axis. The end portion is then forced into the passage. Forming the braided shield with this method helps prevent the plurality of wires from unraveling and reduces corrosion between the housing and the support. Accordingly, the braided shield provided herein reduces or eliminates the number of holes in the shield to reduce or eliminate electromagnetic radiation from entering or exiting a cable while providing a strong and consistent crimp with the support. Such a cable may be useful in any industry or application, including, but not limited to, an electric vehicle's propulsion system wiring to prevent from a radio or other electronic sources.
Referring to the figures, wherein like numerals indicate like or corresponding parts throughout the several views, an exemplary braided shield is shown at numeral 10.
A support 22 is at least partially disposed in the passage 20 of the housing 12. The support 22 has a relatively rigid structure for generally retaining the shape of the housing 12 when assembled. The support 22 may be formed from any known material. For instance, the support 22 may be formed from steel or aluminum. Also, the support 22 may be coated with a metal such as tin. It is to be appreciated that the support 22 may be formed from or coated with other materials known in the art.
A crimp band 24 is disposed on the outer layer 14 for securing the support 22 to the housing 12. The crimp band 24 may be formed from any material known in the art. For instance, the crimp band 24 may be formed from steel and plated with tin. The crimp band 24 includes at least one crimp end 26 that may be compressed, effectively shortening the circumference of the crimp band 24. When the crimp end 26 is compressed, the crimp band 24 holds the housing 12 and the support 22 together.
The support 22 may further include a lip 36 integrally formed with and extending from the support 22 transverse to the longitudinal axis 18. The lip 36 limits movement of the support 22 along the longitudinal axis 18. The lip 36 may also align the crimp band 24 with the end of the housing 12.
It is to be understood that the above description is intended to be illustrative and not restrictive. Many alternative approaches or applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the invention should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the arts discussed herein, and that the disclosed systems and methods will be incorporated into such future examples. In sum, it should be understood that the invention is capable of modification and variation and is limited only by the following claims.
The present embodiments have been particularly shown and described, which are merely illustrative of the best modes. It should be understood by those skilled in the art that various alternatives to the embodiments described herein may be employed in practicing the claims without departing from the spirit and scope as defined in the following claims. It is intended that the following claims define the scope of the invention and that the method and apparatus within the scope of these claims and their equivalents be covered thereby. This description should be understood to include all novel and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any novel and non-obvious combination of these elements. Moreover, the foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application.
All terms used in the claims are intended to be given their broadest reasonable constructions and their ordinary meanings as understood by those skilled in the art unless an explicit indication to the contrary is made herein. In particular, use of the singular articles such as “a,” “the,” “said,” etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary.
