PATENT DOCUMENT

Publication Number: US-8442257-B2
Application Number: US-89229210-A
Country: US
Kind Code: B2

Title: Cables with intertwined jackets

Abstract:
Fibers may be intertwined to form cables for headsets and other structures. The cables may include wires. The wires may be surrounded by a jacket formed from intertwined fibers. The intertwined fibers may include fibers with different melting temperatures. The jacket may be heated to a temperature that is sufficient to melt some of the fibers in the jacket without melting other fibers in the jacket. The melted fibers may flow into spaces between the unmelted fibers and may serve as a binder that holds together the unmelted fibers. The intertwining process may be used to form a bifurcation for a headset. A dipping process may be used to cover the jacket with a coating. The coating may be formed over the entire length of the cable or may be formed in a particular portion of the cable such as the portion of the cable that includes the bifurcation.

Claims:
What is claimed is: 
     
       1. Headphones, comprising:
 a fiber-based cable comprising:
 a first plurality of fibers intertwined with a second plurality of fibers; and 
 
 a coating disposed over the first plurality of fibers, wherein the coating is at least partially formed from at least one melted portion of the second plurality of fibers. 
 
     
     
       2. The headphones defined in  claim 1  wherein the coating at least partially comprises a polymer. 
     
     
       3. Headphones, comprising:
 a fiber-based cable; and 
 speakers, wherein the fiber-based cable includes a coating, wherein the coating comprises a polymer, wherein the fiber-based cable includes first fibers and second fibers, wherein the first fibers have a melting point lower than the second fibers, and wherein the coating is formed at least partly from melted portions of the first fiber. 
 
     
     
       4. The headphones defined in  claim 3  wherein the first fibers comprise nylon. 
     
     
       5. The headphones defined in  claim 4  wherein the second fibers comprise polyethylene terephthalate. 
     
     
       6. The headphones defined in  claim 1  wherein each fiber of the first plurality of fibers comprises nylon and each fiber of the second plurality of fibers comprises polyethylene terephthalate. 
     
     
       7. The headphones defined in  claim 1  wherein the coating at least partially comprises a dipped polymer coating. 
     
     
       8. Apparatus, comprising:
 wires; and 
 intertwined fibers that form a jacket that surrounds the wires to form a cable, wherein the intertwined fibers include first fibers and second fibers, wherein the first fibers have a first melting temperature, wherein the second fibers have a second melting temperature, and wherein the jacket includes at least some melted portions of the first fibers in spaces between unmelted portions of the second fibers. 
 
     
     
       9. The apparatus defined in  claim 8  wherein the first fibers include nylon fibers. 
     
     
       10. The apparatus defined in  claim 8  wherein the second fibers include polyethylene terephthalate fibers. 
     
     
       11. The apparatus defined in  claim 8  further comprising a dipped polymer coating on the jacket. 
     
     
       12. The apparatus defined in  claim 8  further comprising a connector. 
     
     
       13. The apparatus defined in  claim 12  wherein the connector comprises an audio jack. 
     
     
       14. The apparatus defined in  claim 8  wherein the intertwined fibers comprise braided fibers. 
     
     
       15. The apparatus defined in  claim 14  wherein the jacket comprises a bifurcation. 
     
     
       16. The apparatus defined in  claim 15  further comprising a pair of speakers connected to the wires and an audio jack connected to the wires. 
     
     
       17. The headphones defined in  claim 1 , wherein:
 each fiber of the first plurality of fibers comprises a first melting point; and 
 each fiber of the second plurality of fibers comprises a second melting point that is different from the first melting point. 
 
     
     
       18. The headphones defined in  claim 1 , wherein the headphones further comprises at least one audio component coupled to a portion of the fiber-based cable. 
     
     
       19. The headphones defined in  claim 18 , wherein the at least one audio component comprises at least one of a speaker and an audio jack. 
     
     
       20. The headphones defined in  claim 1  further comprising at least one conductor disposed within the fiber-based cable.

Description:
BACKGROUND 
     This invention relates to structures formed from intertwined fibers, and more particularly, to ways in which to form structures for electronic devices from intertwined fibers. 
     Electronic devices such as music players often use headsets. Some headsets are formed from wires that are contained within a cable having a fiber cable jacket. The use of fiber cable jackets may be more aesthetically pleasing than the use of uniform plastic cable jackets. Fiber cable jackets may, however, be subject to wear when exposed to the environment. If care is not taken, a fiber cable jacket may become soiled or may allow moisture to penetrate the interior of the cable. 
     It would therefore be desirable to be able to provide improved structures formed from intertwined fibers, such as improved headset cables for electronic devices. 
     SUMMARY 
     Cables for headsets and other structures may be formed from intertwined fibers (e.g., braided or interwoven fibers). The intertwined fibers may be formed by fiber intertwining equipment. The fiber intertwining equipment may braid or interweave the fibers to form a cable jacket that surrounds wires and a strengthening cord. The cable jacket may contain a bifurcation. Left and right speakers may be attached to the ends of the cable above the bifurcation. Below the bifurcation, the cable may be terminated in an audio jack. 
     The fibers that are intertwined to form the cable jacket may include polymer fibers, metal fibers, insulator-coated metal fibers, glass fibers, or other suitable fibers. The fibers that are intertwined may have different properties. For example, fibers with a first melting temperature may be intertwined with fibers with a second melting temperature that is greater than the first melting temperature. By raising the temperature of the jacket to a temperature that is between the first and second melting temperatures, the first fibers may be melted to form a binder that binds together the second fibers, which remain unmelted. 
     Other binders may also be incorporated into the fibers that make up the cable jacket. These binders may include epoxy and other thermoset materials, thermoplastic materials, etc. 
     Some or all of the cable jacket may be coated with a coating layer. The coating layer may be formed by dipping the jacket into a liquid such as a polymer precursor. To strengthen the cable jacket in the vicinity of the bifurcation, a segment of the cable jacket that includes the bifurcation may be dipped in the liquid coating material while remaining portions of the cable are exposed to air. 
     Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative accessory such as a headset that has been formed from intertwined fibers in accordance with an embodiment of the present invention. 
         FIG. 2  is a cross-sectional view of a cable with a fiber jacket of the type that may be used in apparatus of the type shown in  FIG. 1  in accordance with an embodiment of the present invention. 
         FIG. 3  is a cross-sectional view of a portion of a jacket formed from intertwined fibers in accordance with an embodiment of the present invention. 
         FIG. 4  is a schematic diagram of illustrative equipment that may be used in forming cables and associated devices in accordance with an embodiment of the present invention. 
         FIG. 5  is a flow chart of illustrative steps involved in forming structures based on intertwined fibers using equipment of the type shown in  FIG. 4  in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Cables that are formed from jackets with intertwined fibers may be used in headphones, patch cords, power cords, or other equipment they conveys electrical signals. As an example, cables having jackets with intertwined fibers are sometimes described herein in the context of accessories such as headsets. This is, however, merely illustrative. Any suitable apparatus may be provided with a cable having a jacket formed from intertwined fibers if desired. 
     An illustrative headset is shown in  FIG. 1 . As shown in  FIG. 1 , headset  88  may include a main cable portion  92 . Cable  92  may be formed from intertwined fibers and may have portions formed from different types and amounts of fibers and different patterns and amounts of binder and coatings (as examples). Speakers  90  may be mounted at the ends of the right and left branches of cable  92 . In region  94 , cable  92  may have a bifurcation (forked region). Feature  96  may be an enclosure for a switch, microphone, etc. The end of cable  92  may be terminated by audio jack  98 . 
     A cross-sectional view of cable  92  is shown in  FIG. 2 . As shown in  FIG. 2 , cable  92  may have a jacket such as jacket  100  (sometimes referred to as a sheath). Jacket  100  may enclose fibers such as fibers  102 . Fibers  102  may include wires for conducting electrical signals. Wires may be used to carry power, digital signals, analog signals, etc. Wires may include stranded conductors or solid conductors. Wire insulation may be provided by dielectric coatings (e.g., polymer coatings). Fibers  102  may also include one or more strengthening cords (e.g., a cord formed from polymer fibers such as aramid fibers). Electromagnetic shielding structures (e.g., intertwined or wrapped foil conductive sheaths that surround bundles of wires within jacket  100 ) may also be included in cable  92 . 
     Cable  92  may include any suitable number of wires (e.g., one or more). For example, cable  92  may include two wires (e.g., a positive wire and a negative wire). Cable  92  may also include three wires, four wires, five wires, six wires, or more than six wires. Arrangements with more wires may be used to handle additional audio channels (e.g., left and right speaker channels, surround sound channels, etc.). Arrangements with more wires may also be able to use two or more wires for conveying power (e.g., by forming a power path that is not used to handle any data signals or that handles only a minimal number of data signals). The incorporation of additional wires within cable  92  may also allow cable  92  to handle control signals (e.g., by providing a signal path for conveying signals from a controller in region  96  of headset  88  of  FIG. 1  to connector  98 ). 
     Jacket  100  may include intertwined fibers, binder materials (sometimes referred to as matrix materials) such as epoxy or other binders that fill interstitial spaces between intertwined fibers, coatings, or other suitable structures. Optional layers such as electromagnetic sheaths, dielectric sheaths, and other layers may be interposed between jacket  100  and fibers  102  if desired. 
     As shown in the illustrative cross-sectional view of jacket  100  of  FIG. 3 , jacket  100  may have a coating layer such as optional outer layer  104  and intertwined fibers  106 . Layer  104  may be formed from polymer. Although shown as being formed on top of fibers  106  in  FIG. 3 , some of layer  104  may, if desired, penetrate into fibers  106 . For example, layer  104  may be formed by dipping cable  92  into a liquid coating material. The liquid may impregnate some or all of fibers  106  and, when cured, may form dipped polymer coating  104 . A layer such as layer  104  (i.e., an inner sheath layer) may also be formed beneath fibers  106 . 
     Fibers  106  may be formed in one or more layers. Multiple layers of fibers  106  are shown in  FIG. 3  as an example. Fibers  106  may be formed from any suitable materials. Examples of fibers  106  include metal fibers (e.g., strands of steel or copper), glass fibers (e.g., fiber-optic fibers that can internally convey light through total internal reflection), plastic fibers, etc. Some fibers may exhibit high strength (e.g., polymers such as aramid fibers). Other fibers such as nylon may offer good abrasion resistance (e.g., by exhibiting high performance on a Tabor test). Yet other fibers may be highly flexible (e.g., to stretch without exhibiting plastic deformation). Fibers may have different magnetic properties, different thermal properties, different melting points, different dielectric constants, different conductivities, different colors, etc. 
     Different fibers may melt (soften) at different temperatures. For example, fibers  106  may include two (or more) different types of fibers such as fibers  108  and  110  of  FIG. 3 . Fibers  108  may be formed from a first material such as nylon and fibers  110  may be formed from a second material such as polyethylene terephthalate (PET). In this type of arrangement fibers  108  may exhibit a lower melting point than fibers  110 . For example, fibers  108  (e.g., nylon) may melt at a temperature in the range of about 100 to 120° C., whereas fibers  110  (e.g., PET) may melt at a temperature of 130° C. or more. When fibers  108  and  110  melt at different temperatures, the fibers that melt at the lower temperature may be melted to form a binder for the fibers that melt at the higher temperature. 
     Consider, as an illustrative example, a scenario in which fibers  108  have a melting temperature of 110° C. and fibers  110  have a melting temperature of 130° C. After fibers  108  and  110  have been intertwined using an intertwining tool, fibers  108  and  110  may be heated to an intermediate temperature such as 120° C. At this temperature, fibers  108  will melt and fibers  110  will not melt. Molten material from fibers  108  may therefore flow throughout fibers  110  and, when cooled, will form a binder that helps bind fibers  110  together. By binding fibers  110  together in this way, jacket  100  may be made resistant to the intrusion of moisture and dust. 
     If desired, other binders may be included in jacket  100 . For example, binder  112  may be incorporated into the interstitial spaces between respective fibers  106 . Binder  112  may be formed from epoxy or other suitable materials. These materials may sometimes be categorized as thermoset materials (e.g., materials such as epoxy that are formed from a resin that cannot be reflowed upon reheating) and thermoplastics (e.g., materials such as acrylonitrile butadiene styrene, polycarbonate, and ABS/PC blends that are reheatable). Both thermoset materials and thermoplastics and combinations of thermoset materials and thermoplastic materials may be used as binders if desired. When it is desired to include within fibers  106  at least some fibers  108  that melt to form a binder for unmelted fibers  110 , fibers  108  may be formed from a thermoplastic material. 
     The fibers of cable  92  including jacket fibers  106  and interior fibers  102  (e.g., wires and strengthening cord) may be formed from metal, dielectric, or other suitable materials. The fibers of cable  92  may be relatively thin (e.g., less than 20 microns or less than 5 microns in diameter—i.e., carbon nanotubes or carbon fiber) or may be thicker (e.g., metal wire). The fibers of cable  92  may be formed from twisted bundles of smaller fibers (sometimes referred to as filaments) or may be formed as unitary fibers of a single untwisted material. Regardless of their individual makeup (i.e., whether thick, thin, or twisted or otherwise formed from smaller fibers), the strands of material that make up the wires, strengthening cords, and fibers in jacket  100  are referred to herein as fibers. In some contexts, the fibers of cable  92  may also be referred to as cords, threads, ropes, yarns, filaments, strings, twines, etc. 
     Fabrication equipment of the type that may be used to form headset  88  is shown in  FIG. 4 . As shown in  FIG. 4 , fabrication equipment  10  may be provided with fibers from fiber sources  12 . Fiber sources  12  may provide fibers of any suitable type. Examples of fibers include metal fibers (e.g., strands of steel or copper with or without insulating coatings such as sheaths of plastic), glass fibers (e.g., fiber-optic fibers that can internally convey light through total internal reflection), plastic fibers, etc. 
     Intertwining tool(s)  14  may be based on any suitable fiber intertwining technology. For example, intertwining equipment  14  may include computer-controlled intertwining tools (e.g., braiding tools or weaving tools). Equipment  14  may be used to form tubular interwoven or braided structures such as jacket  100  surrounding wires and one or more strengthening cords (see, e.g., fibers  102  of  FIG. 2 ). Seamless bifurcations (see, e.g., bifurcation  94  of  FIG. 1 ) may be formed in a tubular jacket using equipment  14 . In this type of configuration, some of wires  102  will follow the left-hand branch of cable  92  and some of the wires will follow the right-hand branch of cable  92  above bifurcation  94 . Between bifurcation  94  and connector  98 , all of fibers  102  may be surrounded by a single jacket. Tool  14  may form the portion of the jacket that lies between connector  98  and bifurcation  94  from 32 fibers (as an example). Above bifurcation  94 , 16 of the 32 fibers may be intertwined to form the jacket for the left-hand branch of cable  92  and 16 of the 32 fibers may be intertwined to form the jacket for the right-hand branch of cable  92 . 
     Tools  16  may be used to process cable  92  after jacket  100  has been formed around fibers  102 . Tools  16  may include tools  18  such as molds, spraying equipment, and other suitable equipment for incorporating binder into portions of the intertwined fibers produced by intertwining equipment  14 . Tools  16  may also include dipping tools such as tool  20  for forming coatings such as coating  104  of  FIG. 3 . Coating  104  may, for example, be formed by dipping jacket  100  into a binder such as a liquid polymer. Heating tools such as heating tool  22  may be used to apply heat to cable  92  (e.g., to melt, dry, or cure a binder, to melt fibers such as fibers  108  in jacket  100 , etc.). Heating tool  22  may be implemented using an oven, a heat lamp (e.g., an infrared lamp), a laser heating tool, a hot plate, a heated mold, or other heating equipment. An ultraviolet (UV) lamp may be included in tools  16  for UV curing operations. Cutting tool  24  may include blades or other cutting equipment for dividing jacket  100  and fibers  102  into desired lengths for forming cable  92  for accessory  88 . The tools of equipment  16  may be controlled by computers or other suitable control equipment. If desired, additional tools may be included in equipment  16 . The examples of  FIG. 4  are merely illustrative. 
     Equipment in system  10  such as intertwining tool  14  and equipment  16  may be used to form finished parts such as finished part  26  (e.g., cable  92  for headset  88  of  FIG. 1 ) or other structures from fibers provided from fiber sources  12 . 
     Tools  16  may, if desired, include computer-controlled equipment and/or manually operated equipment that can selectively incorporate binder into different portions of a workpiece in different amounts. For example, when it is desired to stiffen a fiber structure, more resin can be incorporated into the intertwined fiber, whereas less resin can be incorporated into the intertwined fiber when a flexible structure is being formed. Different portions of the same structure can be formed with different flexibilities in this way. Following curing (e.g., using heat or ultraviolet light, the binder will stiffen and harden). The resulting structure (finished part  26 ) can be used in a computer structure, a structure for other electrical equipment, headset  88 , etc. 
     Illustrative steps involved in using equipment of the type shown in  FIG. 4  to form cable  92  and other such structures is shown in  FIG. 5 . 
     At step  200  fibers such as fibers  102  for the interior of cable  92  and fibers such as fibers  106  for cable jacket  100  may be loaded into fiber sources  12 . 
     At step  202 , tool  14  may be used to form jacket  100  around fibers  102 , as shown in  FIG. 2 . Fibers  102  may include metal wires (e.g., insulated or uninsulated wires of stranded and/or solid copper) and one or more strengthening cords. Cable components such as shielding layers may be formed around fibers  102  (e.g., before feeding fibers  102  into the intertwining tool). Tool  14  may braid, interweave, or otherwise intertwine fibers  106  around fibers  102 . As shown in  FIG. 3 , fibers  106  may include one or more different types of fiber (e.g., a low melting temperature fiber  108  and a high melting temperature fiber  110  and/or other fibers). 
     During the operations of steps such as steps  204 ,  206 , and  208 , cable  92  may be completed using tools  16 . During these steps, tool  18  may incorporate binder into the fibers, tool  20  may be used to dip the cable into a liquid, heating tool  22  may apply heat, cutting tool  24  may make cuts, etc. Any suitable order may be used in performing these steps. 
     In the example of  FIG. 5 , cutting tool  24  may be used to cut the cable into sections each of which includes a respective bifurcation  94  during the operations of step  204 . 
     Following the operations of step  204 , tool  20  may, at step  206 , be used incorporated polymers and other suitable materials into the fibers. For example, thermoset and/or thermoplastic binders may be incorporated into the fibers of cable  92 . Tool  20  may, if desired, be used to dip the cable or a selected segment of the cable into a liquid (e.g., a polymer precursor for forming coating  104 ). When dipped into the liquid, the liquid may flow into the spaces between fibers  106  (e.g., to form coating  104 ). The liquid may be cured by heat or by application of UV light or may be cured at room temperature (e.g., when the liquid is formed from a mixed two-part epoxy), etc. 
     Precursors for coating  104  may also be formed by spraying, by placing the cable in a chamber containing a vapor of precursor material, using multiple applications of coating chemicals, etc. Coating  104  may be formed from a flexible substance to help preserve the flexibility of cable  92 , a substance that helps strengthen the portion of the cable that is coated with coating  104 , or substances with other desirable properties (e.g., to adjust the color of cable  92 , to adjust the soil-repelling nature of cable  92 , to adjust the ability of cable  92  to withstand wear, or to change other properties of cable  92 ). 
     Coating  104  may help prevent dirt and moisture from entering the spaces between fibers  106  and may help prevent fibers  106  from unwinding. This may help preserve the appearance of cable  92 . If, for example, cable  92  is formed from white fibers, the formation of coating  104  over and/or between the white fibers may help prevent dark pieces of dirt from becoming lodged between the white fibers. Coating  104  may therefore prevent cable  92  from becoming soiled and appearing dirty. To help repel dirt, coating  104  may be formed from a dirt-repelling substance (e.g., a fluorosurfactant). Other illustrative materials that may be used to form coating  104  include parylene or other oleophobic materials, fluorine-based materials, silicone, acrylic-based materials, etc. 
     Coating  104  may be formed over substantially all of cable  92  (e.g., over the entire cable length shown in  FIG. 1 ) or may be formed on part of cable  92 . For example, coating  104  may be formed over a portion of cable  92  in the vicinity of bifurcation  94  (e.g., within a segment of 1-8 cm in length, within a segment of less than 1 cm in length, or within a segment of less than 4 cm in length that is centered over bifurcation  94 ). A segment of coating  104  may be formed, for example, by dipping only bifurcation  94  of cable  92  into the coating liquid, while leaving remaining portions of cable  92  exposed to air. This type of arrangement may be used to provide localized strength enhancement to the portion of cable  92  that includes bifurcation  94 , without unnecessarily decreasing the flexibility of the remaining portions of cable  92 . 
     Heat may be applied to cable  92  at step  208  to cure materials that were incorporated into the fibers of the cable during the operations of step  204 . For example, heat may be applied to cure an epoxy binder or other thermoset binder that was incorporated into cable fibers. Heat may also be applied to melt a thermoplastic binder. For example, heat may be applied at step  208  to melt at least some of fibers  108  so that they flow into the spaces between unmelted fibers  110  as described in connection with  FIG. 3 . The process of melting and resolidifying fibers  108  may form a binder throughout fibers  106  (e.g., to form coating  104  and/or to form binder in internal locations such as interstitial binder locations  112  of  FIG. 3 ). The presence of melted fibers  108 , coating  104 , binder  112 , or other materials between fibers  106  may help prevent dirt and moisture from entering cable  92 . 
     The order of the cable fabrication operations shown in  FIG. 5  is merely illustrative. If desired, step  208  may be performed before steps  204  and/or  206 , step  206  may be performed before step  204 , other steps may be performed in forming cable  92  and accessory  88 , some or all of these steps may be performed simultaneously, etc. 
     The foregoing is merely illustrative of the principles of this invention and various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention.

Metadata:
Filing Date: 20100928
Publication Date: 20130514
Grant Date: 20130514
Priority Date: 20100928
Inventors: AASE JONATHAN S.
WEBER DOUGLAS
Assignee: APPLE INC
CPC Classifications: [{"code": "H04R1/1033", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01B13/16", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01B13/0013", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R1/1033", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01B13/16", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 45870683