PATENT DOCUMENT

Publication Number: US-11076664-B1
Application Number: US-201715816248-A
Country: US
Kind Code: B1

Title: Fabric cases for electronic devices

Abstract:
Fabric may be woven using a needle weaving machine. The needle weaving machine may have three weft fiber needles and two hooks for holding weft fibers from the weft fiber needles. One of the weft fiber needles may provide weft fibers to multiple hooks when weaving fabric with warp fibers held in a V-shaped profile. An electronic device may have a rectangular footprint with four curved corners. A length of fabric may be woven to form a case having four curved corners that match the four curved corners of the electronic device. The case may have a C-shaped profile with parallel upper and lower fabric portions coupled by a sidewall. Short rows of weft fiber may be used around the corners of the case to ensure that the upper and lower portions of the fabric lie flush with planar front and rear surfaces of the electronic device.

Claims:
What is claimed is: 
     
       1. A fabric case for an electronic device, comprising:
 warp fibers and weft fibers; 
 four woven straight fabric segments that are formed with the warp fibers and weft fibers; and 
 four woven curved corners that are formed with the warp fibers and weft fibers, wherein the four woven corners are formed between the four woven straight segments, wherein the woven straight fabric segments and the curved corners have a C-shaped profile, wherein the C-shaped profile has upper, lower, and side portions and wherein a weft fiber in the weft fibers extends through each of the upper, lower, and side portions. 
 
     
     
       2. The fabric case defined in  claim 1  wherein the weft fibers form short rows in the corners. 
     
     
       3. The fabric case defined in  claim 2  wherein the woven straight fabric segments include first, second, third, and fourth woven straight segments, wherein the first and second segments extend along a first dimension and the third and fourth segments extend along a second dimension. 
     
     
       4. The fabric case defined in  claim 3  further comprising a planar rear wall coupled to the lower portion of the C-shaped profile. 
     
     
       5. The fabric case defined in  claim 1  wherein the four woven corners each include an upper fabric portion with weft fibers that form short rows and a lower fabric portion with weft fibers that form short rows. 
     
     
       6. The fabric case defined in  claim 5  wherein the four woven corners each include a sidewall fabric portion that extends from the upper fabric portion to the lower fabric portion. 
     
     
       7. The fabric case defined in  claim 6  wherein the upper and lower fabric portions are parallel and wherein the sidewall fabric portion is perpendicular to the upper and lower fabric portions. 
     
     
       8. The fabric case defined in  claim 1  wherein the four woven straight fabric segments and the four woven curved corners form a ring-shaped fabric structure having an upper planar portion, a lower planar portion that lies parallel to the upper planar portion, and a sidewall portion that extends from the upper planar portion to the lower planar portion. 
     
     
       9. A fabric case for an electronic device, comprising:
 a rear wall; 
 a lower fabric portion; 
 an upper fabric portion; 
 four sidewalls coupled between the upper and the lower fabric portions, wherein the rear wall, the lower fabric portion, and the four sidewalls surround a cavity; 
 four corners interspersed with the four sidewalls, wherein each of the four corners comprises:
 warp fibers; and 
 first and second weft fibers, wherein the first weft fiber overlaps fewer warp fibers than the second weft fiber; and 
 
 a seam, wherein the seam extends through the upper fabric portion, the lower fabric portion, and one of the four sidewalls. 
 
     
     
       10. The fabric case defined in  claim 9  wherein each of the four corners comprises a third weft fiber that overlaps an equivalent number of warp fibers as the first weft fiber, and wherein the second weft fiber is interposed between the first and third weft fibers. 
     
     
       11. The fabric case defined in  claim 9  wherein the rear wall comprises a layer of plastic. 
     
     
       12. The fabric case defined in  claim 9  wherein the rear wall comprises woven fabric. 
     
     
       13. The fabric case defined in  claim 9  wherein the rear wall comprises fabric that is integral with the four sidewalls. 
     
     
       14. A fabric case for an electronic device, comprising:
 first and second sidewalls; 
 first and second opposing fabric ends, wherein the first and second opposing fabric ends are joined along a seam on the first sidewall; 
 warp strands; and 
 first, second, and third weft strands, wherein the second weft strand is located between the first and third weft strands, wherein the first and third weft strands overlap a first number of the warp strands, wherein the second weft strand overlaps a second number of the warp strands, and wherein the second number is greater than the first number. 
 
     
     
       15. The fabric case defined in  claim 14  further comprising:
 first and second fabric segments that extend respectively along first and second perpendicular dimensions; and 
 a corner fabric portion located between the first and second fabric segments, wherein the first, second, and third weft strands are located in the corner fabric portion. 
 
     
     
       16. The fabric case defined in  claim 15  further comprising:
 a rear wall portion coupled to the first and second fabric segments. 
 
     
     
       17. The fabric case defined in  claim 16  wherein the rear wall portion comprises woven fabric. 
     
     
       18. The fabric case defined in  claim 15  wherein the corner fabric portion has a curved profile.

Description:
This application is a continuation of patent application Ser. No. 14/861,625, filed Sep. 22, 2015, which claims the benefit of provisional patent application No. 62/053,731 filed Sep. 22, 2014, both of which are hereby incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     This relates generally to fabric, and, more particularly, to forming fabric for structures such as cases for electronic devices. 
     Electronic devices such as cellular telephones, computers, and other electronic equipment are sometimes used in conjunction with external cases. A user may, for example, place an electronic device in a removable plastic case to protect the electronic device from scratches. Removable cases may also be used to personalize electronic devices. 
     Plastic cases may be satisfactory in certain situations, but some users may desire a case with different aesthetics. As a result, fabric cases have been developed. 
     There are challenges associated with forming fabric cases for electronic devices. If care is not taken, fabric cases may not wear well, may be bulky, or may have an undesirable appearance. 
     It would therefore be desirable to be able to provide improved removable cases for electronic devices. 
     SUMMARY 
     Fabric may be woven to form a removable case for an electronic device or other fabric structures. The fabric may be woven using a needle weaving machine. The needle weaving machine may have three weft fiber needles and two hooks for holding weft fibers from the weft fiber needles. One of the weft fiber needles may provide weft fibers to both of the hooks when weaving fabric with warp fibers held in a V-shaped profile. Fabric from the needle weaving machine may be received within a take down system that has one or more rollers formed from individually controllable rotating disks. 
     An electronic device may have a rectangular footprint with four curved corners. A length of fabric may be woven to form a case having four curved corners that match the four curved corners of the electronic device. The case may have a C-shaped profile with parallel upper and lower fabric portions coupled by a vertical sidewall. Short rows of weft fiber may be woven into corner portions of the upper and lower fabric portions of the case to ensure that the upper and lower portions of the fabric lie flush with planar front and rear surfaces of the electronic device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device in accordance with an embodiment. 
         FIG. 2  is a perspective view of an illustrative electronic device to which a removable case has been attached in accordance with an embodiment. 
         FIG. 3  is s perspective view of an illustrative removable electronic device case in accordance with an embodiment. 
         FIG. 4  is a cross-sectional view taken along line  24 , also labeled as IV-IV, and viewed in direction  26  of a removable case with peripheral walls surrounding a central opening in accordance with an embodiment. 
         FIG. 5  is a cross-sectional view of a removable case with peripheral walls that surround a rectangular planar rear wall in accordance with an embodiment. 
         FIG. 6  is a top view of illustrative needle weaving equipment of the type that may be used in forming fabric for a removable electronic device case or other fabric structures in accordance with an embodiment. 
         FIG. 7  is a side view of illustrative needle weaving equipment being used to weave an electronic device case in accordance with an embodiment. 
         FIG. 8  is a top view of a corner portion of a woven fabric case in accordance with an embodiment. 
         FIG. 9  is a perspective view of an illustrative take down system based on a pair of cone-shaped rollers in accordance with an embodiment. 
         FIG. 10  is a perspective view of an illustrative take down system based on a pair of rollers each of which has a set of independently controlled rotating disks in accordance with an embodiment. 
         FIG. 11  is a perspective view of an illustrative donut-shaped fabric structure formed using a weaving system in accordance with an embodiment. 
         FIG. 12  is a cross-sectional side view of an edge portion of an illustrative fabric case in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may be provided with cases such as fabric cases. The fabric cases may be removable external cases. When a user desires to protect an electronic device from scratches or other damage, the user may place an electronic device within a case. When the user wishes to use a different case to change the appearance of an electronic device, the electronic device may be transferred from one case to another. If desired, fabric may be incorporated into an electronic device housing or may be used in forming other fabric-based structures. Arrangements in which fabric is used in forming removable external cases are sometimes described herein as an example. 
     The fabric for a removable case may be woven, knitted, or braided, or may be formed using other fiber intertwining techniques. For example, fabric can be woven using a needle weaving machine. 
     An electronic device of the type that may be provided with a removable case that has been woven using a needle weaving machine is shown in  FIG. 1 . In the example of  FIG. 1 , device  10  includes a display such as display  14  mounted in housing  12 . Housing  12 , which may sometimes be referred to as an enclosure or case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of any two or more of these materials. Housing  12  may be formed using a unibody configuration in which some or all of housing  12  is machined or molded as a single structure or may be formed using multiple structures (e.g., an internal frame structure, one or more structures that form exterior housing surfaces, etc.). 
     Display  14  may be a touch screen display that incorporates a layer of conductive capacitive touch sensor electrodes or other touch sensor components (e.g., resistive touch sensor components, acoustic touch sensor components, force-based touch sensor components, light-based touch sensor components, etc.) or may be a display that is not touch-sensitive. Display  14  may include an array of pixels formed from liquid crystal display (LCD) components, an array of electrophoretic pixels, an array of plasma pixels, an array of organic light-emitting diode pixels or other light-emitting diodes, an array of electrowetting pixels, or pixels based on other display technologies. 
     Display  14  may be protected using a display cover layer such as a layer of transparent glass or clear plastic. The display cover layer may form a planar front face for device  10 . The rear of housing  12  may have a parallel planar surface. Housing sidewalls may run around the periphery of housing  12 . Device  10  may have a rectangular outline (e.g., a rectangular footprint when viewing the front face of the device) or may have other suitable footprints. 
     Openings may be formed in the display cover layer. For example, an opening may be formed in the display cover layer to accommodate a button such as button  16 . An opening may also be formed in the display cover layer to accommodate ports such as speaker port  18 . Openings may be formed in housing  12  to form communications ports (e.g., an audio jack port, a digital data port, etc.), to form openings for buttons, etc. 
     Electronic device  10  may be a computing device such as a laptop computer, a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wrist-watch device, a pendant device, a headphone or earpiece device, a device embedded in eyeglasses or other equipment worn on a user&#39;s head, or other wearable or miniature device, a television, a computer display that does not contain an embedded computer, a gaming device, a navigation device, an embedded system such as a system in which electronic equipment with a display is mounted in a kiosk or automobile, equipment that implements the functionality of two or more of these devices, or other electronic equipment. In the illustrative configuration of  FIG. 1 , device  10  is a portable device such as a cellular telephone, media player, tablet computer, or other portable computing device. Other configurations may be used for device  10  if desired. The example of  FIG. 1  is merely illustrative. 
       FIG. 2  is a perspective view of device  10  of  FIG. 1  in a configuration in which device  10  has been mounted in a removable case. As shown in  FIG. 2 , removable case  20  may have walls that run around the periphery of device  10 . If desired, case  20  may form a cover with a hinged portion, a structure with a pocket into which device  10  may slide, or other enclosure that receives device  10 . In the example of  FIG. 2 , case  20  surrounds device  10 , but does not cover display  14 . This type of arrangement, which may be desirable for devices such as cellular telephones, watches, and tablet computers, allows display  14  to be viewed by a user without opening a cover flap or moving any portion of case  20 . If desired, however, case  20  may be provided with pockets, flaps, hinged portions, straps, and other structures. The configuration of  FIG. 2  is merely illustrative. 
       FIG. 3  is a perspective view of case  20  of  FIG. 2  in a configuration in which device  10  is not present (i.e., a configuration in which case  20  has been removed from device  10 ). As shown in  FIG. 3 , case  20  may have four straight segments each of which runs along and covers a respective one of the four straight peripheral edges of the rectangular housing of device  10 . Corner portions of the case join the straight segments together to form a case with a rectangular ring shape. Corners  20 E may be rounded when viewed from above (i.e., when case  20  has a footprint with rounded corners) or may have other shapes. Central opening  22  may have a rectangular shape (e.g., a rectangular shape with rounded corners) or other shape suitable for receiving electronic device  10  when electronic device  10  is mounted within case  20 . 
     A cross-sectional view of case  20  of  FIG. 3  taken along line  24  and viewed in direction  26  is shown in  FIG. 3 . As shown in  FIG. 3 , case  20  may have sidewalls such as vertical fabric sidewalls  30  that join respective upper horizontal wall portion  28  and lower horizontal wall portion  32 . This forms a C-shaped channel that runs around the periphery of device  10  when device  10  is installed within case  20 . The rectangular C-shaped cross-sectional shape of case  20  of  FIG. 4  (i.e., the shape in which upper and lower horizontal wall portions  28  and  32  lie in planes that are parallel to each other and that are perpendicular to the plane of vertical fabric sidewall  30 ) is merely illustrative. If, for example, device  10  has edges with a curved cross-sectional shape, the C-shaped profile of case  20  may have a correspondingly curved shape (e.g., vertical fabric sidewall  30  may bow outwards). Moreover, the fabric of case  20  may be formed from fibers that are elastic to accommodate devices  10  with a variety of different edge profiles and footprints. The example of  FIGS. 3 and 4  is merely illustrative. 
       FIG. 5  is a cross-sectional side view of case  20  in a configuration in which rear wall portion  34  has been incorporated into case  20 . Rear wall portion  34  may be formed from a layer of plastic or metal or may be formed from a layer of fabric. Rear wall portion  34  may cover some or all of the rear of device  10  and may be attached to lower horizontal wall portions  32  or woven or formed as an integral portion of lower horizontal wall portions  32 . 
       FIG. 6  is a top view of an illustrative needle weaving system of the type that may be used to form woven removable cases such as case  20  and other fabric structures. As shown in  FIG. 6 , system  36  may be provided with fibers from fiber source  38 . Fiber source  38  may include a warping creel. The fibers provided by fiber source  38  may be single-strand filaments or may be threads, yarns, or other fibers that have been formed by intertwining single-strand filaments. Fibers may be formed from polymer, metal, glass, graphite, ceramic, natural materials such as cotton or bamboo, or other organic and/or inorganic materials and combinations of these materials. Conductive coatings such as metal coatings may be formed on non-conductive fiber cores. Fibers may also be formed from single filament metal wire or stranded wire. Fibers may be insulating or conductive. Fibers may be conductive along their entire length or may have conductive segments (e.g., metal portions that are exposed by locally removing polymer insulation from an insulated conductive fiber). Threads and other multi-strand fibers that have been formed from intertwined filaments may contain mixtures of conductive fibers and insulating fibers (e.g., metal fibers or metal coated fibers with or without exterior insulating layers may be used in combination with solid plastic fibers or natural fibers that are insulating). 
     Fiber source  38  may provide warp fibers  40 . Weft fibers  46  may also be supplied to system  36  from a source such as source  38 . Weft fibers  46  may be formed from the same materials as warp fibers  40  or may be formed from different materials. During weaving, warp fibers  40  and weft fibers  46  may be woven together to form fabric  56 . 
     Warp fibers  40  may pass through computer-controlled warp fiber positioning equipment  42 . Warp fiber positioning equipment  42  may sometimes be referred to as a Jacquard head or Jacquard. During operation, warp fiber positioning equipment  42  may be used to selectively deflect warp fibers  40  in directions such as upwards direction Z and/or downwards direction Z). When being used to form a fabric with a plain weave, for example, warp fiber positioning equipment  42  may deflect even warp fibers  40  upwards while leaving odd fibers in a neutral position to create a temporary vertical space known as a shed between these two sets of warp fibers. Following insertion of a weft thread into the shed formed between the upper and lower warp fibers, a shed change may be performed in which warp fiber positioning equipment  42  places the even warp fibers  40  in a neutral (undeflected) position and deflects odd warp fibers upwards. Individual warp fibers  40  and/or sets of two or more warp fibers  40  can be deflected in this way using warp fiber positioning equipment  42 . 
     During weaving operations, weft fiber positioning equipment  50  may be used to insert weft fiber  46  in the shed between sets of deflected warp fibers  40 . Weft fiber positioning equipment  50  may include a computer-controlled positioner such as positioner  52  that positions a weft fiber dispensing structure such as weft fiber needle  54 , so weft fiber positioning equipment  50  may sometimes be referred to as a needle. 
     Needle  54  may be moved across warp fibers  40  (e.g., in directions along dimension Y). Initially, needle  54  moves in direction Y to deliver weft fiber  46  to hook  48 . Hook  48  (e.g., a hook and computer-controlled latch mechanism or any other mechanism that can engage weft fiber  46 ) temporarily holds onto the weft fiber that has been delivered to hook  48  by needle  54 . Needle  54  may then be retracted in direction −Y to lay weft fiber  46  across warp fibers  40 . After each pass of needle  54  across warp fibers  40 , reed  44  may be moved in direction X (and then retracted in in direction −X) to push the weft fiber that has just been inserted though the shed in the warp fibers against previously woven fabric  56 , thereby ensuring that a satisfactorily tight weave is produced. Each time reed  44  is retracted, a shed change may be performed, followed by delivery of an additional length of weft fiber  46  by needle  54 . Fabric  56  that has been woven in this way may be gathered on take down system  64 . Take down system  64  (sometimes referred to as a take down) may have one or more rollers such as roller  62 . Roller  62  may rotate about axis  58  in direction  60  to tension warp fibers  40  while gathering fabric  56 . 
     Using the creel of source  38  and warp fiber positioning equipment  42 , warp fibers  40  may be positioned into a pattern of the type shown in the cross-sectional view of  FIG. 5 . In particular, warp fibers  40  may be positioned to form upper horizontal warp fiber portion  40 - 1 , parallel lower horizontal warp fiber portion  40 - 3 , and two intermediate diagonal warp fiber portions  40 - 2 A and  40 - 2 B. Intermediate diagonal warp fiber portions  40 - 2 A and  40 - 2 B form a V-shaped profile that joins upper horizontal warp fiber portion  40 - 1  to lower horizontal warp fiber portion  40 - 3 . After weaving is complete (i.e., after fabric  56  for case  20  has been woven), upper horizontal warp fiber portion  40 - 1  will form upper horizontal wall portion  28 , intermediate diagonal warp fiber portions  40 - 2 A and  40 - 2 B will be pulled into a planar vertical orientation (i.e., the V-shaped profile will be opened up) and will form vertical fabric sidewall  30 , and lower horizontal warp fibers portion  40 - 3  will form lower horizontal wall portion  32 . The warp fibers of the structure of  FIG. 7  may all be formed from the same type of fibers or different sections of the warp fibers may be formed from different types of fiber (e.g., the warp fibers and weft fiber used in forming the fabric of intermediate diagonal warp fiber portions  40 - 2 A and  40 - 2 B may be formed from elastic materials to help the sidewall fabric of the V-shaped portion to open up when device  10  is mounted in case  20 ). 
     When the V-shaped fabric of  FIG. 7  opens up to form vertical fabric sidewall  30 , upper and lower horizontal wall portions  28  and  32  may lie flush with the upper and lower surfaces of device  10 . In a finished version of case  20 , opposing ends of fabric  56  will be joined along a seam such as seam  40 M of  FIG. 3 . When device  10  is installed in case  20 , the warp fibers in vertical fabric sidewall of case  20  will run along the periphery of device  10  (e.g. parallel to the outermost edge of housing  12 ). 
     As shown in  FIG. 7 , weaving system  36  may have three needles (needles  54 - 1 ,  54 - 2 , and  54 - 3 ) and two hooks ( 48 A and  48 B). Needle  54 - 1  may be used to dispense weft fiber  46 - 1 , needle  54 - 2  may be used to dispense weft fiber  46 - 2 , and needle  54 - 3  may be used to dispense weft fiber  46 - 3 . Hooks  48 A and  48 B may be used to temporarily hold onto weft fiber that has been moved across the warp fibers by the needles. 
     Needle  54 - 1  may move back and forth through a shed defined in upper horizontal warp fiber portion  40 - 1  along dimension Y during weaving of upper horizontal wall portion  28  of case  20 . Hook  48 A may be used to temporarily hold weft fiber  46 - 1  that has been delivered to hook  48 A by needle  54 - 1  during weaving of upper horizontal wall portion  28  from weft fiber  46 - 1  and upper horizontal warp fiber portion  40 - 1 . 
     Similarly, needle  54 - 3  may move back and forth along dimension Y through the shed formed in lower horizontal warp fiber portion  40 - 3  during weaving of lower horizontal wall portion  32  of case  20 . Hook  48 B may be used to temporarily hold weft fiber  46 - 3  that has been delivered to hook  48 B by needle  54 - 1  when weaving of lower horizontal wall portion  32  from weft fiber  46 - 3  and lower horizontal warp fiber portion  40 - 3 . 
     Needle  54 - 2  may pull weft fibers across the V-shaped profile of intermediate diagonal warp fiber portion  40 - 2 A and  40 - 2 B during weaving operations. Initially, needle  54 - 2  may move to the right in direction  66  to move weft fiber from a position such as position  70  on the left edge of intermediate diagonal warp fiber portion  40 - 2 A to a position on the right of intermediate diagonal warp fiber portion  40 - 2 A such as position  72 . Needle  54 - 2  may then move to the left (direction  68 ) to move weft fiber  46 - 2  back across intermediate diagonal warp fiber portion  40 - 2 A. Hook  48 A may hold weft fiber  46 - 2  in position  72 , while needle  54 - 2  is retracted across intermediate diagonal warp fiber portion  40 - 2 A. At this point warp fiber positioning equipment  42  may be used to perform a shed change (i.e., sets of warp fibers may reverse positions to capture the weft). Needle  54 - 2  may then be used to dispense the weft across intermediate diagonal warp fiber portion  40 - 2 B by moving from position  70  to position  74  (moving to the right in direction  76 ). Hook  48 B may hold weft fiber  46 - 2  that has been delivered to hook  48 B by needle  54 - 2 . Needle  54 - 2  may then be retracted to the left (direction  78 ) and another shed change performed using warp fiber positioning equipment  42 . This process (and the processes of laterally moving needles  54 - 1  and  54 - 3 ) may be performed repeatedly, thereby forming fabric  56  with a cross-sectional profile of the type shown in  FIG. 7 . Chain stitches  80  and  82  may be formed respectively along the interface between upper horizontal warp fiber portion  40 - 1  and intermediate diagonal warp fiber portion  40 - 2 A and along the interface between intermediate diagonal warp fiber portion  40 - 2 B and lower horizontal warp fiber portion  40 - 3  to secure the weft fibers at these locations (e.g., using a monofilament chain stitch). Once weaving is complete and once the opposing ends of an appropriately sized length of fabric  56  have been joined at seam  40 M, the fabric of case  20  may be stretched around the periphery of device  10 , as shown in  FIG. 2 . 
     To accommodate rounded corners in device housing  12 , case  20  may be provided with woven rounded corners  20 E. The flat vertical portion of case  20  (i.e., vertical fabric sidewall  30 ) can bend around the corner. The horizontal portions of case  20  (e.g., upper and lower horizontal wall portions  28  and  32 ) are preferably woven in a way that helps accommodate the curved corner shape of device  10  and case  20 . 
       FIG. 8  is a top view of upper horizontal warp fiber portion  40 - 1  along one of the corners  20 E of case  20  during weaving. As corner  20 E is formed, the amount of weft fiber  46 - 1  that is required to produce a flat fabric will vary as a function of radial position R. Portions of the fabric of corner  20 E that are near the inner edge of corner  20 E (i.e., smaller R values) will require fewer weft fibers than regions of the fabric that are nearer the outer edge of corner  20 E (i.e. larger R values). This spatially varying need for weft fibers can be accommodated by incorporating short rows of weft fibers into the fabric, as shown in  FIG. 8 . Some rows of weft fiber  46 - 1  traverse all of upper horizontal warp fiber portion  40 - 1 . In short rows, weft fiber  46 - 1  will only be incorporated within a smaller number of warp fibers in upper horizontal warp fiber portion  40 - 1 . The selection of which warp fibers in upper horizontal warp fiber portion  40 - 1  are used to entrap weft fibers  46 - 1  (and therefore the resulting length of each weft fiber row in the fabric) may be made using warp fiber positioning equipment  42  ( FIG. 6 ). 
     The characteristics of fabric  56  (e.g., the number of picks per inch and the curvature of fabric  56 ) can be influenced by take down system  64 .  FIG. 9  shows an illustrative configuration for take down system  64  that is based on a pair of conical rollers  62 - 1  and  62 - 2 . During weaving, woven fabric  56  is drawn between rollers  62 - 1  and  62 - 2  as shown in  FIG. 9 . The surfaces of rollers  62 - 1  and  62 - 2  may be covered with an abrasive material such as sandpaper to help grip the fibers of fabric  56 . This tensions one edge of fabric  56  more than the other and creates a curve in the fabric that is being woven. When incorporating short rows into the weft, as described in connection with  FIG. 8 , the surface of the fabric that is formed in this wall may be smooth and uniform. 
     Some fabric structures (e.g., donut-shaped structures) may be created by continuously drawing fabric  56  through a take down system based on conical rollers of the type shown in  FIG. 9 . Other fabric structures (e.g., case  20  of  FIG. 3 ) may have a combination of straight (non-curved) fabric segments and curved fabric segments (e.g., corners  20 E). To produce fabric with a curvature that varies as a function of distance along its length, computer-controlled rollers of the type shown in  FIG. 10  may be used. 
     In illustrative take down system  64  of  FIG. 10 , rollers  62 - 1  and  62 - 2  rotate towards each other around respective rotational axes  58 - 1  and  58 - 2 , respectively. Fabric  56  that is being woven with system  36  may be drawn between rollers  62 - 1  and  62 - 2 . Each roller may have a series of independently controlled rotating disks  84 . 
     When it is desired to form a straight length of fabric  56 , all of the portions of fabric  56  may be tensioned equally by rotating all disks  84  in unison. In this mode of operation, rollers  62 - 1  and  62 - 2  act as disks  84  that are joined together. 
     When it is desired to form a curved section of fabric  56 , the individual disks of each roller may be rotated at different speeds. For example, the speed of rotation of each disk may be increased with increasing distance along the rotational axis of the roller (along at least a portion of the roller) to replicate the tensioning effects produced by a set of conical rollers of  FIG. 9 . In the take down system of  FIG. 9 , opposing disks  84 - 1 A and  84 - 2 A may be rotated in directions  60 A and  60 B at a first speed. Opposing disks  84 - 1 B and  84 - 2 B, which are located farther along the rollers, may be rotated in directions  60 A and  60 B at a second speed that is greater than the first speed. Disks  84 - 1 C and  84 - 2 C may be rotated at a third speed that is greater than the second speed and so forth to produce a desired rotation speed profile across rollers  62 - 1  and  62 - 1 . Controlling the individual disks  84  of rollers  62 - 1  and  62 - 2  in this way allows curved fabric for corners  20 E of case  20  to be formed. 
     System  36  may, if desired, be used to form a donut-shaped fabric structure such as fabric  56  of  FIG. 11 . Fabric  56  of  FIG. 11  may be formed, for example, using conical rollers  62 - 1  and  62 - 1  or rollers  62  with individually rotating disks  84  in take down system  64 , as described in connection with  FIGS. 9 and 10 . When it is desired to form a completed fabric structure, a seam may be formed by joining ends  88  and  90 . Foam or other materials may be placed in an interior donut-shaped cavity formed within the interior of fabric  56  of  FIG. 11 . The inner edge of the donut may then be joined together (e.g., the inner edges of fabric  56  may be joined using a circular seam that runs around the circular interior edge of the donut). Donut-shaped fabric structures may be used in headsets and other electronic device accessories (as an example). 
     As shown in  FIG. 12 , case  20  may be formed using multiple layers of warp fibers  40 . In the example of  FIG. 12 , upper horizontal warp fiber portion  40 - 1  is three layers thick, warp fibers  40 - 2  are three layers wide, and lower horizontal warp fiber portion  40 - 3  is three layers thick. In general, the number of layers of warp fibers  40  that are stacked next to each other may be two or more, three or more, five or more 10 or more, 20 or more, 50 or more, less than 75, less than 15, or other suitable number. Weft fibers  46  may follow paths through varying numbers of warp fibers as shown in  FIG. 12 . Chain stitches  80  and  82  may be formed along the periphery of case  20  (e.g., along the upper peripheral edge of case  20  and along the lower peripheral edge of case  20  in a C-shaped case of the type shown in  FIG. 3 ). The fabric of case  20  in the example of  FIG. 12  may be formed using a needle weaving system such as system  36  of  FIG. 6  or other suitable equipment. 
     In general, any suitable fabric structures may be produced using weaving system  36  of  FIG. 6 . The formation of a woven case such as case  20  and a donut-shaped structure such as the structure of  FIG. 11  is merely illustrative. 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20171117
Publication Date: 20210803
Grant Date: 20210803
Priority Date: 20140922
Inventors: PODHAJNY, DANIEL A.
CREWS, KATHRYN P.
Assignee: APPLE INC
CPC Classifications: [{"code": "A45F5/1525", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45F5/1516", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C11/003", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C11/002", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C11/002", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C11/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C11/001", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C11/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D47/04", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D25/005", "inventive": true, "first": true, "tree": "[]"}, {"code": "D03D3/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D25/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D41/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C11/00", "inventive": true, "first": true, "tree": "[]"}, {"code": "D03D41/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45F2200/0525", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C11/00", "inventive": true, "first": true, "tree": "[]"}, {"code": "D03D25/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C2011/003", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45F2200/0516", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C2011/002", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 77063236