PATENT DOCUMENT

Publication Number: US-8562890-B2
Application Number: US-201113013557-A
Country: US
Kind Code: B2

Title: Method for molding a cable structure

Abstract:
A headset can include a cable structure connecting non-cable components such as jacks and headphones. The cable structure can be constructed using a molding process. Different approaches can be used to ensure that a conductor bundle extending through the cable structure remains centered within the cable structure during the molding process. In some cases, a movable tube can be placed in the mold such that the conductor bundle is retained within the tube. As material is injected into the mold and reaches the tube, the tube can be displaced and progressively removed from the mold. Alternatively, the movable tube can be constructed such that the tube may combine with injected material to form a shell of the cable structure. In some cases, gates from which material is provided in the mold can be positioned and controlled to facilitate the injection of material in the mold while maintaining the centered position of the conductor bundle.

Claims:
What is claimed is: 
     
       1. A method for molding a cable structure, comprising:
 placing a conductor bundle in a tube, the conductor bundle having an outer diameter, the tube having an inner diameter that is substantially the same as the outer diameter of the conductor bundle, the inner diameter being substantially uniform laterally along the tube; 
 placing the tube with the conductor bundle in a mold, the tube further having an outer diameter that is selected based on the dimensions of the mold; 
 injecting material into the mold; and 
 progressively extracting the tube from the mold while leaving the conductor bundle in the mold. 
 
     
     
       2. The method of  claim 1 , wherein placing the conductor bundle further comprises:
 placing the conductor bundle in the tube such that the conductor bundle extends beyond at least one end of the tube. 
 
     
     
       3. The method of  claim 1 , wherein the mold comprises a substantially straight section in which the tube can be received. 
     
     
       4. The method of  claim 1 , wherein injecting material further comprises injecting material in a region of the mold adjacent to an end of the tube. 
     
     
       5. The method of  claim 4 , wherein:
 the mold comprises at least three legs interfacing in a bifurcation region; and 
 injecting material further comprises injecting material adjacent to the bifurcation region. 
 
     
     
       6. The method of  claim 5 , wherein:
 a tube is placed in each of the at least three legs. 
 
     
     
       7. The method of  claim 1 , wherein extracting further comprises:
 identifying a position of a material front for the injected material; and 
 extracting the tube relative to the identified position of the material front. 
 
     
     
       8. The method of  claim 7 , wherein extracting further comprises:
 displacing the tube using pressure caused by the material front. 
 
     
     
       9. The method of  claim 1 , wherein extracting further comprises:
 displacing the tube using an actuator. 
 
     
     
       10. A method for centering a conductor bundle within a molded cable structure, comprising:
 providing a mold for a cable structure, the mold defining a cylindrical volume comprising at least one open end; 
 providing a conductor bundle to place within the mold, wherein molded material encapsulates the conductor bundle, the conductor bundle having an outer diameter; 
 inserting a tube within the mold, the tube comprising a tube wall with a thickness substantially the same as a thickness of material enclosing the conductor bundle within the cable structure, the tube comprising an inner diameter that is substantially the same as the outer diameter of the conductor bundle, the inner diameter being substantially uniform along a length of the tube; 
 injecting material into the mold; and 
 progressively removing the tube from the mold as material is injected into the mold. 
 
     
     
       11. The method of  claim 10 , wherein removing the tube further comprises:
 removing the tube from the mold through the at least one open end. 
 
     
     
       12. The method of  claim 10 , further comprising:
 applying tension to the conductor bundle to maintain the conductor bundle taut within the mold. 
 
     
     
       13. The method of  claim 10 , wherein:
 the tube combines with the material injected into the mold to create a shell for the cable structure. 
 
     
     
       14. The method of  claim 13 , wherein:
 the tube dissipates upon contact with the material injected into the mold. 
 
     
     
       15. The method of  claim 7 , wherein identifying the position of the material front comprises using a sensor. 
     
     
       16. The method of  claim 5 , further comprising:
 securing the conductor bundle in the bifurcation region with a guide. 
 
     
     
       17. The method of  claim 1 , further comprising:
 opening at least one gate in accordance with a position of the tube being extracted; and 
 injecting material into the mold via the at least one gate. 
 
     
     
       18. The method of  claim 1 , wherein the outer diameter that is selected is substantially the same as the inner diameter of the mold.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of previously filed U.S. Provisional Patent Application No. 61/298,087, filed Jan. 25, 2010, entitled “Small Diameter Cable with Splitter Assembly,” U.S. Provisional Patent Application No. 61/384,103, filed Sep. 17, 2010, entitled “Molded Splitter Structures and Systems and Methods for Making the Same,” U.S. Provisional Patent Application No. 61/319,772, filed Mar. 31, 2010, entitled “Thin Audio Plug and Coaxial Routing of Wires,” U.S. Provisional Patent Application No. 61/384,097, filed Sep. 17, 2010, entitled “Cable Structures and Systems Including Super-Elastic Rods and Methods for Making the Same,” U.S. Provisional Patent Application No. 61/326,102, filed Apr. 20, 2010, entitled “Audio Plug with Core Structural Member and Conductive Rings,” U.S. Provisional Patent Application No. 61/349,768, filed May 28, 2010, entitled “Molding an Electrical Cable Having Centered Electrical Wires,” U.S. Provisional Patent Application No. 61/378,311, filed Aug. 30, 2010, entitled “Molded Cable Structures and Systems and Methods for Making the Same,” and U.S. Provisional Application No. 61/378,314, filed Aug. 30, 2010, entitled “Extruded Cable Structures and Systems and Methods for Making the Same.” Each of these provisional applications is incorporated by reference herein in their entireties. 
    
    
     BACKGROUND OF THE INVENTION 
     Wired headsets are commonly used with many portable electronic devices such as portable music players and mobile phones. Headsets can include non-cable components such as a jack, headphones, and/or a microphone and one or more cables that interconnect the non-cable components. The one or more cables can be manufactured using different approaches. 
     SUMMARY OF THE INVENTION 
     Molded multi-segment cable structures and systems and methods for molding cable structures are provided. In particular, systems and methods for maintaining a conductor bundle centered within a molded multi-segment cable structure are provided. 
     A cable structure can interconnect various non-cable components of a headset such as, for example, a plug, headphones, and/or a communications box to provide a headset. The cable structure can include several legs (e.g., a main leg, a left leg, and a right leg) that each connect to a non-cable structure, and each leg may be connected to one another at a bifurcation region (e.g., a region where the main leg appears to split into the left and right legs). Cable structures according to embodiments of this invention can include a conductor bundle to provide a conductive path between the non-cable components of the cable structure 
     To provide an aesthetically pleasing cable structure, material can be molded over the conductor bundle. The mold can ensure a smooth and continuous outer surface for the cable structure. To mold a cable structure, a conductor bundle can initially be provided substantially at a centerline of the mold, and material can subsequently be injected into the mold. The pressure at which the material is injected, however, can cause the conductor bundle to be displaced from the centerline of the mold. 
     Different approaches can be used to maintain a conductor bundle centered within a mold. In some cases, a movable tube can be placed in the mold such that the conductor bundle is retained within the tube. As material is injected into the mold and reaches the tube, the tube can be displaced and progressively removed from the mold. The tube can translate within the mold under the control of an actuator, due to pressure from injected material, or combinations of these. Alternatively, the movable tube can be constructed such that the tube may combine with injected material to form a shell of the cable structure. In some cases, gates from which material is provided in the mold can be positioned and controlled (e.g., opened to allow different amounts of material) to facilitate the injection of material in the mold while maintaining the centered position of the conductor bundle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features of the present invention, its nature and various advantages will be more apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings in which: 
         FIGS. 1A and 1B  illustrate different headsets having a cable structure that seamlessly integrates with non-cable components in accordance with some embodiments of the invention; 
         FIGS. 1C and 1D  show illustrative cross-sectional views of a portion of a leg in accordance with some embodiments of the invention; 
         FIG. 1E  shows an illustrative headset having a variable diameter in accordance with some embodiments of the invention; 
         FIG. 2  is a sectional view of an illustrative mold for constructing a jointly formed multi-segment cable structure in accordance with some embodiments of the invention; 
         FIG. 3  is a sectional view of a portion of a mold for a cable structure in which conductor bundles are retained using movable tubes in accordance with some embodiments of the invention; 
         FIG. 4  is a sectional view of a portion of a mold for a cable structure in which movable tubes for constraining conductor bundles are moved in accordance with some embodiments of the invention; 
         FIG. 5  is a sectional view of an illustrative mold for a cable structure having centered conductor bundles in accordance with one embodiment of the invention; 
         FIG. 6  is a sectional view of a portion of a mold for a cable structure, the mold having a runner with several gates through which material is provided in accordance with some embodiments of the invention; 
         FIG. 7  is a sectional view of a portion of a mold for a cable structure in which tubes maintaining a position of a conductor bundle are incorporated in the cable structure in accordance with some embodiments of the invention; 
         FIG. 8  is a sectional view of a portion of a mold for a cable structure in which a conductor bundle can be retained by removable pins in accordance with some embodiments of the invention; 
         FIG. 9  is a sectional view of a portion of a mold corresponding to a leg of a multi-segment cable structure having dynamic components in accordance with some embodiments of the invention; 
         FIGS. 10A and 10B  are sectional views of different molds that can be used to mold a cable structure having a centered conductor bundle using a two-shot molding process in accordance with one embodiment of the invention; 
         FIG. 11  is flowchart of an illustrative process for molding a cable structure having a centered conductor bundle in accordance with some embodiments of the invention; and 
         FIG. 12  is a flowchart of an illustrative process for centering a conductor bundle within a molded cable structure in accordance with some embodiments of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     Cable structures for use in headsets are disclosed. The cable structure interconnects various non-cable components of a headset such as, for example, a plug, headphones, and/or a communications box to provide a headset. The cable structure can include multiple legs (e.g., a main leg, a left leg, and a right leg) that each connect to a non-cable component, and each leg may be connected to each other at a bifurcation region (e.g., a region where the main leg appears to split into the left and right legs). Cable structures according to embodiments of this invention provide aesthetically pleasing interface connections between the non-cable components and legs of the cable structure. The interface connections between a leg and a non-cable component are such that they appear to have been constructed jointly as a single piece, thereby providing a seamless interface. 
     In addition, because the dimensions of the non-cable components typically have a dimension that is different than the dimensions of a conductor bundle being routed through the legs of the cable structure, one or more legs of the cable structure can have a variable diameter. The change from one dimension to another is accomplished in a manner that maintains the spirit of the seamless interface connection between a leg and the non-cable component throughout the length of the leg. That is, each leg of the cable structure exhibits a substantially smooth surface, including the portion of the leg having a varying diameter. In some embodiments, the portion of the leg varying in diameter may be represented mathematically by a bump function, which requires all aspects of the variable diameter transition to be smooth. In other words, a cross-section of the variable diameter portion can show a curve or a curve profile. 
     The interconnection of the three legs at the bifurcation region can vary depending on how the cable structure is manufactured. In one approach, the cable structure can be a single-segment unibody cable structure or a jointly formed multi-leg cable structure. In this approach, all three legs are jointly formed and no additional processing is required to electrically couple the conductors contained therein. Construction of the single-segment cable may be such that the bifurcation region does not require any additional support. If additional support is required, an over-mold can be used to add strain relief to the bifurcation region. 
     In another approach, the cable structure can be a multi-segment unibody cable structure or a cable structure having three discrete or independently formed legs that are connected at a bifurcation region. In this approach, the legs may be manufactured as discrete segments, but require additional processing to electrically couple conductors contained therein. The segments can be joined together using a splitter. Many different splitter configurations can be used, and the use of some splitters may be based on the manufacturing process used to create the segment. 
     The cable structure can include a conductor bundle that extends through some or all of the legs. The conductor bundle can include conductors that interconnect various non-cable components. The conductor bundle can also include one or more rods constructed from a superelastic material. The superelastic rods can resist deformation to reduce or prevent tangling of the legs. 
     The cable structure can be constructed using many different manufacturing processes. The processes include injection molding, compression molding, and extrusion. In injection molding processes (e.g., liquid injection molding, or LIM), a mold is formed around a conductor bundle or a removable rod. The rod is removed after the mold is formed and a conductor bundle is threaded through the cavity. 
       FIG. 1A  shows an illustrative headset  10  having cable structure  20  that seamlessly integrates with non-cable components  40 ,  42 , and  44 . For example, non-cable components  40 ,  42 , and  44  can be a male plug, left headphones, and right headphones, respectively. Cable structure  20  has three legs  22 ,  24 , and  26  joined together at bifurcation region  30 . Leg  22  may be referred to herein as main leg  22 , and includes the portion of cable structure  20  existing between non-cable component  40  and bifurcation region  30 . In particular, main leg  22  includes interface region  31 , bump region  32 , and non-interface region  33 . Leg  24  may be referred to herein as left leg  24 , and includes the portion of cable structure  20  existing between non-cable component  42  and bifurcation region  30 . Leg  26  may be referred to herein as right leg  26 , and includes the portion of cable structure  20  existing between non-cable component  44  and bifurcation region  30 . Both left and right legs  24  and  26  include respective interface regions  34  and  37 , bump regions  35  and  38 , and non-interface regions  36  and  39 . 
     Legs  22 ,  24 , and  26  generally exhibit a smooth surface throughout the entirety of their respective lengths. Each of legs  22 ,  24 , and  26  can vary in diameter, yet still retain the smooth surface. 
     Non-interface regions  33 ,  36 , and  39  can each have a predetermined diameter and length. The diameter of non-interface region  33  (of main leg  22 ) may be larger than or the same as the diameters of non-interface regions  36  and  39  (of left leg  24  and right leg  26 , respectively). For example, leg  22  may contain a conductor bundle for both left and right legs  24  and  26  and may therefore require a greater diameter to accommodate all conductors. In some embodiments, it is desirable to manufacture non-interface regions  33 ,  36 , and  39  to have the smallest diameter possible, for aesthetic reasons. As a result, the diameter of non-interface regions  33 ,  36 , and  39  can be smaller than the diameter of any non-cable component (e.g., non-cable components  40 ,  42 , and  44 ) physically connected to the interfacing region. Since it is desirable for cable structure  20  to seamlessly integrate with the non-cable components, the legs may vary in diameter from the non-interfacing region to the interfacing region. 
     Bump regions  32 ,  35 , and  38  provide a diameter changing transition between interfacing regions  31 ,  34 , and  37  and respective non-interfacing regions  33 ,  36 , and  39 . The diameter changing transition can take any suitable shape that exhibits a fluid or smooth transition from any interface region to its respective non-interface region. For example, the shape of the bump region can be similar to that of a cone or a neck of a wine bottle. As another example, the shape of the taper region can be stepless (i.e., there is no abrupt or dramatic step change in diameter, or no sharp angle at an end of the bump region). Bump regions  32 ,  35 , and  38  may be mathematically represented by a bump function, which requires the entire diameter changing transition to be stepless and smooth (e.g., the bump function is continuously differentiable). 
     As shown in  FIG. 1E , cable structure  20  can include legs  22 ,  24  and  26  that interface at bifurcation region  30 . Each leg can have a varying diameter or shape to provide a cable structure with a smooth outer surface and appealing cosmetic features. 
       FIGS. 1C and 1D  show illustrative cross-sectional views of a portion of main leg  22  in accordance with embodiments of the invention. Both  FIGS. 1C and 1D  show main leg  22  with a center axis (as indicated by the dashed line) and symmetric curves  32   c  and  32   d . Curves  32   c  and  32   d  illustrate that any suitable curve profile may be used in bump region  32 . Thus the outer surface of bump region  32  can be any surface that deviates from planarity in a smooth, continuous fashion. 
     Interface regions  31 ,  34 , and  37  can each have a predetermined diameter and length. The diameter of any interface region can be substantially the same as the diameter of the non-cable component it is physically connected to, to provide an aesthetically pleasing seamless integration. For example, the diameter of interface region  31  can be substantially the same as the diameter of non-cable component  40 . In some embodiments, the diameter of a non-cable component (e.g., component  40 ) and its associated interfacing region (e.g., region  31 ) are greater than the diameter of the non-interface region (e.g., region  33 ) they are connected to via the bump region (e.g., region  32 ). Consequently, in this embodiment, the bump region decreases in diameter from the interface region to the non-interface region. 
     In another embodiment, the diameter of a non-cable component (e.g., component  40 ) and its associated interfacing region (e.g., region  31 ) are less than the diameter of the non-interface region (e.g., region  33 ) they are connected to via the bump region (e.g., region  32 ). Consequently, in this embodiment, the bump region increases in diameter from the interface region to the non-interface region. 
     The combination of the interface and bump regions can provide strain relief for those regions of headset  10 . In one embodiment, strain relief may be realized because the interface and bump regions have larger dimensions than the non-interface region and thus are more robust. These larger dimensions may also ensure that non-cable portions are securely connected to cable structure  20 . Moreover, the extra girth better enables the interface and bump regions to withstand bend stresses. 
     The interconnection of legs  22 ,  24 , and  26  at bifurcation region  30  can vary depending on how cable structure  20  is manufactured. In one approach, cable structure  20  can be a jointly formed multi-leg or single-segment unibody cable structure. In this approach all three legs are manufactured jointly as one continuous structure and no additional processing is required to electrically couple the conductors contained therein. That is, none of the legs are spliced to interconnect conductors at bifurcation region  30 , nor are the legs manufactured separately and then later joined together. Some jointly formed multi-leg cable structures may have a top half and a bottom half, which are molded together and extend throughout the entire cable structure. For example, such jointly formed multi-leg cable structures can be manufactured using injection molding and compression molding manufacturing processes. Thus, although a mold-derived jointly formed multi-leg cable structure has two components (i.e., the top and bottom halves), it is considered a jointly formed multi-leg cable structure for the purposes of this disclosure. Other jointly formed multi-leg cable structures may exhibit a contiguous ring of material that extends throughout the entire cable structure. For example, such a jointly formed multi-leg cable structure can be manufactured using an extrusion process. 
     In another approach, cable structure  20  can be a multi-segment unibody cable structure in which three discrete or independently formed legs are connected at a bifurcation region. A multi-segment unibody cable structure may have the same appearance of the jointly formed multi-leg cable structure, but the legs are manufactured as discrete components. The legs and any conductors contained therein are interconnected at bifurcation region  30 . The legs can be manufactured, for example, using any of the processes used to manufacture the jointly formed multi-leg cable structure. 
     The cosmetics of bifurcation region  30  can be any suitable shape. In one embodiment, bifurcation region  30  can be an overmold structure that encapsulates a portion of each leg  22 ,  24 , and  26 . The overmold structure can be visually and tactically distinct from legs  22 ,  24 , and  26 . The overmold structure can be applied to the single or multi-segment unibody cable structure. In another embodiment, bifurcation region  30  can be a two-shot injection molded splitter having the same dimensions as the portion of the legs being joined together. Thus, when the legs are joined together with the splitter mold, cable structure  20  maintains its unibody aesthetics. That is, a multi-segment cable structure has the look and feel of jointly formed multi-leg cable structure even though it has three discretely manufactured legs joined together at bifurcation region  30 . Many different splitter configurations can be used, and the use of some splitters may be based on the manufacturing process used to create the segment. 
     Cable structure  20  can include a conductor bundle that extends through some or all of legs  22 ,  24 , and  26 . Cable structure  20  can include conductors for carrying signals from non-cable component  40  to non-cable components  42  and  44 . Cable structure  20  can include one or more rods constructed from a superelastic material. The rods can resist deformation to reduce or prevent tangling of the legs. The rods are different than the conductors used to convey signals from non-cable component  40  to non-cable components  42  and  44 , but share the same space within cable structure  20 . Several different rod arrangements may be included in cable structure  20 . 
     In yet another embodiment, one or more of legs  22 ,  24 , and  26  can vary in diameter in two or more bump regions. For example, the leg  22  can include bump region  32  and another bump region (not shown) that exists at leg/bifurcation region  30 . This other bump region may vary the diameter of leg  22  so that it changes in size to match the diameter of cable structure at bifurcation region  30 . This other bump region can provide additional strain relief. Each leg can have any suitable diameter including, for example, a diameter in the range of 0.4 mm to 1 mm (e.g., 0.8 mm for leg  20 , and 0.6 mm for legs  22  and  24 ). 
     In some embodiments, another non-cable component can be incorporated into either left leg  24  or right leg  26 . As shown in  FIG. 1B , headset  60  shows that non-cable component  46  is integrated within leg  26 , and not at an end of a leg like non-cable components  40 ,  42  and  44 . For example, non-cable component  46  can be a communications box that includes a microphone and a user interface (e.g., one or more mechanical or capacitive buttons). Non-cable component  46  can be electrically coupled to non-cable component  40 , for example, to transfer signals between communications box  46  and one or more of non-cable components  40 ,  42  and  44 . 
     Non-cable component  46  can be incorporated in non-interface region  39  of leg  26 . In some cases, non-cable component  46  can have a larger size or girth than the non-interface regions of leg  26 , which can cause a discontinuity at an interface between non-interface region  39  and communications box  46 . To ensure that the cable maintains a seamless unibody appearance, non-interface region  39  can be replaced by first non-interface region  50 , first bump region  51 , first interface region  52 , communications box  46 , second interface region  53 , second bump region  54 , and second non-interface region  55 . 
     Similar to the bump regions described above in connection with the cable structure of  FIG. 1A , bump regions  51  and  54  can handle the transition from non-cable component  46  to non-interface regions  50  and  55 . The transition in the bump region can take any suitable shape that exhibits a fluid or smooth transition from the interface region to the non-interface regions. For example, the shape of the taper region can be similar to that of a cone or a neck of a wine bottle. 
     Similar to the interface regions described above in connection with the cable structure of  FIG. 1A , interface regions  52  and  53  can have a predetermined diameter and length. The diameter of the interface region is substantially the same as the diameter of non-cable component  46  to provide an aesthetically pleasing seamless integration. In addition, and as described above, the combination of the interface and bump regions can provide strain relief for those regions of headset  10 . 
     In some embodiments, non-cable component  46  may be incorporated into a leg such as leg  26  without having bump regions  51  and  54  or interface regions  52  and  53 . Thus, in this embodiment, non-interfacing regions  50  and  55  may be directly connected to non-cable component  46 . 
     Cable structures  20  can be constructed using many different manufacturing processes. The processes discussed herein include those that can be used to manufacture the jointly formed multi-leg cable structure or legs for the multi-segment unibody cable structure. In particular, these processes include injection molding, compression molding, and extrusion. Embodiments of this invention use extrusion to manufacture a jointly formed multi-leg cable structure or multi-segment unibody cable structures. 
     In some embodiments, cable structure  20  can be constructed by molding material around a rod or around a conductor bundle to form one or more legs of a multi-segment cable structure.  FIG. 2  is a sectional view of an illustrative mold for constructing a jointly formed multi-segment cable structure in accordance with some embodiments of the invention. Mold  200  can be shaped to correspond to multi-segment cable structure  210  having main leg  212 , left leg  214 , and right leg  216 . Different non-cable components can be coupled to ends of legs  212 ,  214  and  216 . For example, an audio plug can be provided at an end of leg  212 , and earbuds or other audio output components can be provided at ends of left leg  214  and right leg  216 . 
     Each of legs  212 ,  214  and  216  can include a conductor bundle for transferring electrical signals through cable structure  210 . For example, left leg  214  can include left conductor bundle  224 , and right leg  216  can include right conductor bundle  226 . Conductor bundles  224  and  226  can combine to form main conductor bundle  222  within main leg  212 . Conductor bundles  222 ,  224  and  226  can serve to transfer any suitable signal including, for example, audio signals corresponding to an earbud or to a microphone, or instructions for controlling the operation of the device. To improve the performance and aesthetic appeal of the device, conductor bundles  222 ,  224  and  226  can be centered in legs  212 ,  214 , and  216 , respectively. 
     To protect the conductor bundles, and to provide an aesthetically pleasing cable structure, a material can be provided over the conductor bundles. In particular, material can be injected within mold  200  to create shell  230  of material in each leg surrounding the conductor bundles. Outer shell  230  can be constructed from any suitable material including, for example, a material selected for mechanical attributes, cosmetic attributes, industrial design attributes, or combinations of these. In some cases, the material can be selected to provide sufficient resistance to abrasions and other contact forces applied to the cable, while allowing the cable to bend freely or comfortably for the user. 
     Shell  230  can have any suitable size relative to conductor bundles  222 ,  224 , and  226 . In some embodiments, shell  230  can have a variable diameter. For example, shell  230  can include a bump region, protruding regions, interlocking or returning regions (e.g., return  252  for coupling with a non-cable component), or any other feature causing the diameter or size of shell  230  to vary. In some embodiments, the diameter or size of shell  230  can vary in a non-uniform manner, for example to feature a non-circular diameter, a hook, protrusion, or another feature (e.g., for engaging an electrical component, such as an audio output interface or a button assembly). As another example, shell  230  can have a varying diameter near bifurcation region  218 , for example to control strain where main leg  222  splits into left leg  224  and right leg  226 . 
     Some molding processes including, for example, injection molding, provide for the injection of material within a mold. In some cases, the injection may occur at relatively high pressure. When conductor bundles are provided in the mold, as shown in mold  200 , the injection of material can cause the conductor bundles to be displaced in the mold and no longer be centered in each leg. This may cause a conductor bundle to sag within shell  230 , become visible through a thin region of shell  230 , or perhaps even extend through shell  230 . Therefore, it may be desirable for the mold or system used for molding a multi-segment cable structure to provide a mechanism for maintaining conductor bundles centered within the mold. 
       FIG. 3  is a sectional view of a portion of a mold for a cable structure in which conductor bundles are retained using movable tubes in accordance with some embodiments of the invention. Mold  300  can include main leg  312 , left leg  314  and right leg  316 . Main conductor bundle  322  can be provided within main leg  312 , and can split into left conductor bundle  324  in left leg  314  and right conductor bundle  326  in right leg  316 . The conductor bundles can be secured in bifurcation region  318  by guide  328  to ensure that the conductor bundles remain centered in the bifurcation region. For example, guide  328  may prevent the conductor bundles from being displaced towards an exterior region of mold  300  in bifurcation region  318  when tension is applied to the conductor bundles. 
     To maintain the conductor bundles centered within their respective legs, mold  300  can include main tube  342  inserted within an open end of main leg  312  (e.g., an end opposite bifurcation region  318 ) and extending towards bifurcation region  318 . Similarly, mold  300  can include left tube  344  inserted within an open end of left leg  314  and extending towards bifurcation region  318 , and right tube  346  inserted within an open end of right leg  316  and extending towards bifurcation region  318 . 
     Each tube can include a hollow portion extending along a length of the tube for receiving a conductor bundle. An inner diameter of the tube can be selected, for example, based on the size of the conductor bundle placed within the tube, and in particular on the number and dimensions of individual conductors placed within a bundle. For cable structures where conductor bundle  322  is larger than conductor bundles  324  or  326 , the inner diameter of main tube  342  may be larger than the inner diameter of left tube  344  or right tube  346 . By selecting the inner diameter of a tube relative to the dimensions of a conductor bundle, the tube can ensure that a conductor bundle will remain centered within the tube. 
     To ensure that the conductor bundle remains centered within each leg, however, it may be necessary to ensure that the tube is centered within the mold. The outer diameter of each tube can be selected based on the dimensions of mold  300  corresponding to a final diameter for outer shell  330  in each leg. In particular, each tube can be sized to substantially fit within a particular leg. In one implementation, the outer diameter selected for each tube can be substantially equal to or marginally smaller than the dimensions of mold  300  for a leg corresponding to the tube. By making the outer diameter of each tube smaller than the smallest dimension of mold  300  for a leg, the tube can slide within mold  300  as material is injected to create shell  330 . 
     The tubes can be formed from any suitable material. In some embodiments, the tubes can be formed from a rigid or semi-rigid material, so that the tubes can retain the bundles along a centerline of the mold. In particular, the tubes can be rigid so that in regions of the mold having larger outer diameters (e.g., regions corresponding to a bump region or an interface region), the tubes can remain centered due to contact between the tubes and regions of the mold that have smaller outer diameters (e.g., regions corresponding to a non-interface region). In some cases, the tube material can be selected based on thermal properties to ensure, for example, that the integrity of a tube is not affected by the heated material injected into the mold. 
     Although mold  300  shows a single tube placed in each leg of the mold, in some cases several tubes or tube segments can be placed end to end within a leg of a mold to maintain a conductor bundle centered. When the several tube segments translate out of an end of a leg, each tube segment can be sequentially removed from the mold. 
     In some cases, tension can be applied to conductor bundles  322 ,  324  and  326  to ensure that the conductor bundles are taut within mold  300 . When tension is applied to the conductor bundles, guide  328  can ensure that the conductor bundles remain centered within bifurcation region  318 . In some cases, the tension can serve to maintain conductor bundles  322 ,  324 , and  326  centered when material is injected into mold  300 . To prevent the conductor bundles from moving relative to one another, guide  328  can include a crimp for securing the conductor bundles. In some cases, guide  328  can provide strain relief to the cable structure at bifurcation region  318 . 
       FIG. 4  is a sectional view of a portion of a mold for a cable structure in which movable tubes for constraining conductor bundles are moved in accordance with some embodiments of the invention. Mold  400  can include main leg  412 , left leg  414 , and right leg  416  each having conductor bundles  422 ,  424 , and  426 , respectively, having some or all of the features described above in connection with mold  300  ( FIG. 3 ). To create shell  430 , material can be injected into mold  400  via gate  460  located adjacent to bifurcation region  418  and guide  428 . Gate  460  can have any suitable size including, for example, a size determined from thermal conductive properties of the material (e.g., how quickly molded material will harden when it flows within the mold), or from an expected rate of flow of the material. 
     Gate  460  can be located at any suitable position along mold  400 . In the example of  FIG. 4 , gate  460  can be placed adjacent to bifurcation region  418  such that material injected into the mold can simultaneously flow into each of legs  412 ,  414 , and  416 . In some embodiments, gate  460  can be positioned or oriented in a manner to bias the flow of material towards one or more of the legs. For example, if main arm  412  is longer or wider than left leg  414  or right leg  416 , gate  460  can be designed such that more material flows towards the main leg  412  than left and right legs  414  and  416 . For example, twice as much material can flow into main leg  412  as in one of left leg  414  and right leg  416 . 
     As the material is injected into mold  400 , indicated by material front  462  in main leg  412 , material front  464  in left leg  414 , and material front  466  in right leg  416 , the material can flow into each leg. The material and mold can be provided such that the material can flow through the entirety of each leg of the mold before hardening and securing the conductor bundles within the cable structure. For example, the material can be heated to a particular temperature at which it becomes more viscous. As another example, portions of mold  400  can be heated or cooled to control the viscosity of the material within the mold. 
     As the material fronts move when material is inserted through gate  460 , it may be necessary to remove the tubes holding the conductor bundles so that the material can fill mold  400  and can adhere to the conductor bundles. In some embodiments, each tube can be displaced along the axis of a leg in which the tube is placed away from gate  460 . For example, as the material front comes near or into contact with a tube, the tube can retract to allow the material to surround the conductor bundles previously retained within the tubes. 
     Any suitable approach can be used to move a tube. In some embodiments, the material front can contact and push away the tubes (e.g., the mold pressure is used to displace a tube). Alternatively, or in addition, one or more actuators, valves, or other mechanisms can be coupled to a tube to remove the tube from a leg in which it is placed, or to control a rate at which the tube is removed (e.g., a motor pulls a tube out of a leg). As another alternative, mold  400  can be oriented substantially vertically such that at least one of legs  412 ,  414 , and  416  extends along a gravity vector. Then, when material is injected into mold  400 , gravity can direct the material into the leg, and can assist in removing a tube from the leg. 
     In some cases, the mold can make use of approaches other than translating tubes to maintain a conductor bundle centered within a leg.  FIG. 5  is a sectional view of an illustrative mold for a cable structure having centered conductor bundles in accordance with one embodiment of the invention. Conductor bundle  522 , including conductors or rods  523  and  524 , can be placed within mold  500  and maintained near a centerline of mold  500 . In some cases, conductor bundle  522  can be substantially equidistant from surfaces of mold  500 . 
     One approach for maintaining conductor bundle  522  substantially centered can include providing material into mold  500  such that material fronts of the injected material surround conductor bundle  522  from opposite directions. For example, mold  500  can include gates  560 ,  562 ,  564  and  564  placed at 90 degree intervals around a periphery of mold  500 . As material is inserted in each gate, material front  561  corresponding to gate  560 , material front  563  corresponding to gate  562 , material front  565  corresponding to gate  566 , and material front  567  corresponding to gate  566  can surround conductor bundle  522 . By controlling the amount, rate and time at which material is provided in each gate, opposing material fronts (e.g., material front  561  and material front  567 ) can reach conductor bundle  522  at the same time. The opposing material fronts can then maintain conductor bundle  522  substantially near the centerline of mold  500 . 
     Mold  500  can include any suitable configuration of gates through which material may be provided. For example, as shown in  FIG. 5 , mold  500  can include four gates having similar dimensions. As another example, mold  500  can include another number of gates disposed at equal intervals around mold  500  (e.g., a number of gates in the range of 2 to 10). Alternatively, if mold  500  includes gates having different sizes or different properties, the distribution of gates can include uneven intervals selected based on the amount of material flowing into the mold through each gate. For example, a mold having three gates can include a first, larger gate at a first position, and two other, smaller gates, offset from the first gate by 150 degrees (and offset from each other by 60 degrees). In some cases, one or more valves can control the amount of flow in each gate. 
       FIG. 6  is a sectional view of a portion of a mold for a cable structure, the mold having a runner with several gates through which material is provided in accordance with some embodiments of the invention. Mold  600  can include main leg  612 , left leg  614 , and right leg  616  each having conductor bundles  622 ,  624 , and  626 , respectively, having some or all of the features described above. To create shell  630 , material can be injected into mold  600  via runner  650 . Runner  650  can include several gates  660  disposed adjacent to one or more of main leg  612 , left leg  614 , right leg  616 , and bifurcation region  618 . Each gate  660  can have any suitable size including, for example, a size determined from thermal conductive properties of the material (e.g., how quickly molded material will harden when it flows within the mold), or from an expected rate of flow of the material. Control circuitry can serve to selectively open one or more gates of runner  650 . 
     Material can be released into mold  600  by gates of runner  650  using any suitable approach. In some embodiments, material can be sequentially or simultaneously released through one or more gates  660  of runner  650 . For example, a gate near bifurcation region  618  can initially be opened, and subsequently gates on each leg can be opened sequentially as material flows away from bifurcation region  618 . The time at which individual gates are opened can be determined from the position of a material front, the position of tubes  642 ,  644 , and  646  (which can include some or all of the features of tubes described above) displaced from within mold  600 , or combinations of these. In some cases, mold  600  can include one or more sensors for determining a current position of a material front. 
     In some embodiments, runner  650  can be heated to ensure that the material used for shell  630  remains sufficiently viscous and liquid to flow through the gates and into the mold. For example, runner  650  can include a heating element that heats the runner to a minimum temperature selected, for example, based on phase change temperatures of the material. 
     In some embodiments, mold  600  may not include tubes  642 ,  644 , and  646 . Instead, gates  660  can be disposed around the periphery of mold  600  (e.g., as shown in  FIG. 5 ) to simultaneously inject, from several directions, material around conductor bundles  622 ,  624  and  626 . As material is injected around conductor bundles  622 ,  624 , and  626 , the conductor bundles can be secured near a centerline of mold  600 . In some cases, however, the disposition of the gates can be combined with movable tubes. 
     In some cases, the material used for a tube placed in a mold can be selected such that the tube may disappear or be integrated with the material.  FIG. 7  is a sectional view of a portion of a mold for a cable structure in which tubes maintaining a position of a conductor bundle are incorporated in the cable structure in accordance with some embodiments of the invention. Mold  700  can include main leg  712 , left leg  714 , and right leg  716  each having conductor bundles  722 ,  724 , and  726 , respectively, having some or all of the features described above. To create shell  730 , material can be injected into mold  700  via gate  760  located adjacent to bifurcation region  718  and guide  728 . Gate  760  can have any suitable size including, for example, a size determined from thermal conductive properties of the material (e.g., how quickly molded material will harden when it flows within the mold), or from an expected rate of flow of the material. As material flows from gate  760  into each of legs  712 ,  714 , and  716 , the material can form a material front in the legs. For example, material can form material front  762  in leg  712 , material front  764  in leg  714 , and material front  766  in leg  716 . 
     Mold  700  can include tubes  742 ,  744 , and  746  surrounding conductor bundles  722 ,  724 , and  726 , respectively so that the conductor bundles remain centered within legs  712 ,  714 , and  716 . In some cases, each tube can be constructed from several segments placed end to end. The individual segments can be placed in contact with each other, or can instead be offset relative to one another. 
     Because it may be complex to displace and remove a tube as a material front approaches, tubes  742 ,  744 , and  746  can be constructed from a material that dissolves, vaporizes, mingles, or otherwise disappears when it is placed in contact with the molded material. For example, a material selected for tubes  742 ,  744 , and  746  can change from a solid phase to a liquid phase when it is heated by the material front. As another example, a chemical bond of the material can be broken when the material front comes into contact with the tube material. The tube material can co-mingle with the molded material to create shell  730 , for example as shown with segments  743 ,  745 , and  747  of tubes  742 ,  744 , and  746 , respectively. Alternatively, the material of each tube segment can vaporize, and the vapors of the material can be evacuated out of mold  700  (e.g., through the open end of each leg). 
     In some cases, conductor bundles can remain centered by removable pins placed within the mold.  FIG. 8  is a sectional view of a portion of a mold for a cable structure in which a conductor bundle can be retained by removable pins in accordance with some embodiments of the invention. Mold  800  can include main leg  812 , left leg  814 , and right leg  816  each having conductor bundles  822 ,  824 , and  826 , respectively, having some or all of the features described above. 
     To retain each conductor bundle near a centerline of a leg, each leg can include a pin assembly that includes several individual pins retaining a conductor bundle. For example, main leg  812  can include pin assembly  832  having pins  833 , left leg  814  can include pin assembly  834  having pins  835 , and right leg  816  can include pin assembly  836  having pins  837 . Each pin can be moved within mold  800  such that in a first configuration, a pin can be placed in contact with a conductor bundle (e.g., to maintain a conductor bundle centered), and in a second configuration, a pin can be removed from the mold (e.g., and form a sidewall of the mold). Pins can be selectively displaced, for example based on a current position of a material front of material injected into mold  800 . 
     Each pin can have any suitable shape. For example, a pin can have a surface formed to correspond to a shape of the conductor bundle. As another example, a pin can have a surface corresponding to an exterior surface of the cable structured to be molded (e.g., when the pin is moved away from the cable structure and becomes a boundary of mold  800 ). The size and spacing of the pins can vary along each leg. For example, pins can be more closely spaced in regions of mold  800  adjacent to bifurcation region  818  to more accurately retain a conductor bundle when material is initially injected into mold  800 . As another example, pins can be larger in regions of mold  800  adjacent to bifurcation region  818 . 
     In some cases, conductor bundles can be maintained in a centered position by using a dynamic mold.  FIG. 9  is a sectional view of a portion of a mold corresponding to a leg of a multi-segment cable structure having dynamic components in accordance with some embodiments of the invention. Conductor bundle  920  can be placed within mold  900 . Mold  900  can include a sequence of mold segments  910  that may be displaced relative to one other in a plane perpendicular to conductor bundle  920 . In particular, adjacent mold segments  910  can be offset relative to one another such that opposite inner surfaces of each mold section are in contact with the conductor bundle. For example, conductor bundle  920  can be supported by an upper inner surface of segment  912 , and by a lower inner surface of segment  914 . Individual segments can alternate in any suitable direction including, for example, sequences of three or more segments offset in different directions. The alternating mold segments can thus maintain conductor bundle  920  in a centered position (e.g., conductor bundle  920  can be statically positioned for a molding process). 
     Material can be injected into mold  900  via gate  960 . As material flows into the mold, segments  910  can be displaced to define the desired shape for the cable structure. Mold segments  910  that are displaced may move to a centered position and release conductor bundle  920 . For example, segments can move to the position shown by segment  916  when material front  962  reaches the beginning of the segment. 
     In some cases, a two-shot molding process can be used to create a cable structure having a centered conductor bundle.  FIGS. 10A and 10B  are sectional views of different molds that can be used to mold a cable structure having a centered conductor bundle using a two-shot molding process in accordance with one embodiment of the invention. Cable structure  1000  can be constructed by placing conductor bundle  1020  successively in two different molds. Initially, conductor bundle can be placed in mold segment  1012   a , over which mold segment  1012   b  can be secured. Material can be injected into mold  1012   b  via gate  1060  to create first half  1050  of a cable structure leg. Once first half  1050  has been molded, it may be removed, along with conductor bundle  1020 , which may be partially secured to first half  1050 , and placed in second mold  1022 . Material can then be provided into mold  1022  through gate  1062  to create second half  1052  of the cable structure leg. The resulting cable structure can include two molded regions around the conductor bundle, which may be centered by virtue of the shape of molds  1012  and  1022 . 
       FIG. 11  is flowchart of an illustrative process for molding a cable structure having a centered conductor bundle in accordance with some embodiments of the invention. Process  1100  can begin at step  1102 . At step  1104 , a conductor bundle can be placed in a mold. For example, a conductor bundle can be routed between different legs of a mold for a multi-segment cable structure. At step  1106 , a tube can be inserted into the mold to center the conductor bundle. For example, a tube having an internal diameter corresponding to dimensions of the conductor bundle, and an outer diameter corresponding to dimensions of each leg of the mold can be inserted in the mold. The conductor bundle can be threaded within the tube to center the conductor bundle relative to the mold. At step  1108 , material can be injected into the mold. For example, material can be injected at a gate near a bifurcation region of the cable structure. At step  1110 , the tube can be progressively removed ahead of a material front of the injected material. For example, an actuator can extract the tube from a leg of the mold as injected material reaches an end of the tube. In some cases, the tube can be absorbed by the injected material to form the cable structure. Process  1100  can end at step  1112 . 
       FIG. 12  is a flowchart of an illustrative process for centering a conductor bundle within a molded cable structure in accordance with some embodiments of the invention. Process  1200  can begin at step  1202 . At step  1204 , a mold for a cable structure can be provided. In some cases, the mold can define a cylindrical volume that includes at least one open end. At step  1206 , a conductor bundle to place in the mold can be provided. Molded material injected into the mold can encapsulate the conductor bundle to form a cable structure. At step  1208 , a tube can be inserted within the mold. The thickness of the tube wall can correspond substantially to a desired thickness of material enclosing the conductor bundle within the cable structure. At step  1210 , material can be injected into the mold. For example, material can be injected into the mold through a gate. At step  1212 , the tube can be progressively removed from the mold. For example, the tube can be removed as material is injected into the mold and reaches an end of the tube. Process  1200  can end at step  1214 . 
     The previously described embodiments are presented for purposes of illustration and not of limitation. It is understood that one or more features of an embodiment can be combined with one or more features of another embodiment to provide systems and/or methods without deviating from the spirit and scope of the invention, and that the order of steps in a process are merely illustrative and can be changed.

Metadata:
Filing Date: 20110125
Publication Date: 20131022
Grant Date: 20131022
Priority Date: 20100125
Inventors: AASE JONATHAN
FRAZIER CAMERON
THOMAS JOHN
Assignee: APPLE INC
CPC Classifications: [{"code": "B29C45/14073", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29K2705/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C43/18", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29K2105/256", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C39/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29L2031/3462", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29K2705/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29L2031/3462", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C33/10", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C2043/3621", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C43/36", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C43/36", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C2043/3665", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C2045/1409", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C2043/3605", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C43/203", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02G15/18", "inventive": true, "first": true, "tree": "[]"}, {"code": "B29C43/18", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C43/203", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C33/10", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C2043/3621", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C2043/3605", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C2045/14131", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29K2105/256", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C2043/3665", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C39/42", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 44308097