PATENT DOCUMENT

Publication Number: US-11292236-B1
Application Number: US-201715650609-A
Country: US
Kind Code: B1

Title: Fabric items with locally thinned fabric

Abstract:
An item such as a fabric-based item may have a layer of fabric such as a layer of woven fabric. The fabric layer may include insulating warp and weft strands. Conductive strands may be woven into the fabric layer and may form electrodes for a touch sensor. Chemical etching or other processing techniques may be used to form an array of openings. In each opening, some or all of the insulating warp and weft strands may be removed so that each opening passes partly or fully through the fabric layer and locally thins the fabric layer. Keys may be formed from key members and switches. The key members may overlap respective locally thinned areas of the fabric layer formed from the openings. The conductive strands may extend across the openings and may be overlapped by the key members and switches.

Claims:
What is claimed is: 
     
       1. A fabric-based item, comprising:
 a fabric layer having an array of locally thinned regions; 
 touch sensor circuitry; 
 touch sensor electrodes in each of the locally thinned regions of the fabric layer that are coupled to the touch sensor circuitry; 
 a dielectric member that overlaps one of the locally thinned regions; and 
 a switch under the dielectric member, wherein the switch detects key press input on the dielectric member and the touch sensor circuitry detects touch input on the fabric layer. 
 
     
     
       2. The fabric-based item defined in  claim 1  wherein the dielectric member comprises a button member in a button. 
     
     
       3. The fabric-based item defined in  claim 1  wherein the fabric layer is configured to form at least part of a wearable band. 
     
     
       4. The fabric-based item defined in  claim 1  wherein the touch sensor electrodes are configured to form part of a trackpad. 
     
     
       5. The fabric-based item defined in  claim 1  wherein the fabric layer is configured to form at least part of a removable electronic device case and wherein the dielectric member comprises a movable button member on the removable electronic device case. 
     
     
       6. The fabric-based item defined in  claim 1  further comprising a haptic output device coupled to the dielectric member. 
     
     
       7. The fabric-based item defined in  claim 1  wherein the touch sensor electrodes comprise wires. 
     
     
       8. The fabric-based item defined in  claim 7  wherein the fabric layer comprises a woven fabric layer and wherein the wires are woven into the fabric layer. 
     
     
       9. The fabric-based item defined in  claim 8  wherein the fabric layer comprises insulating strands of material and wherein each of the locally thinned regions forms an opening in the fabric layer that is free of the insulating strands of material. 
     
     
       10. The fabric-based item defined in  claim 1  wherein each of the locally thinned regions comprises a chemically etched opening that passes through the fabric layer and wherein the touch sensor electrodes overlap the chemically etched opening. 
     
     
       11. The fabric-based item defined in  claim 10  further comprising a key, wherein the touch sensor electrodes comprise wires, wherein the dielectric member comprises a key member in the key, and wherein the key member comprises plastic. 
     
     
       12. The fabric-based item defined in  claim 11  wherein the wires are embedded in the plastic. 
     
     
       13. The fabric-based item defined in  claim 11  wherein the plastic has recesses that receive the wires. 
     
     
       14. The fabric-based item defined in  claim 11  wherein the switch comprises a dome switch in the key, wherein the key includes a key support configured to press against the dome switch, and wherein the wires are interposed between the key support and the key member. 
     
     
       15. The fabric-based item defined in  claim 11  wherein the switch comprises a dome switch, wherein the key includes a key support configured to press against the dome switch and wherein the wires are embedded in the key member. 
     
     
       16. A fabric-based item, comprising:
 a woven fabric layer having insulating warp and weft strands with an array of openings each of which passes at least partly through the woven fabric layer to form a respective locally thinned area; 
 wires woven into the woven fabric layer that extend across each locally thinned area; and 
 planar plastic members each of which overlaps a respective one of the locally thinned areas. 
 
     
     
       17. The fabric-based item defined in  claim 16  wherein the planar plastic members form key members for keys, the fabric-based item further comprising:
 touch sensor circuitry coupled to the wires; 
 switches that each form part of a respective one of the keys; and 
 a substrate on which the switches are mounted. 
 
     
     
       18. The fabric-based item defined in  claim 17  wherein at least some of the wires are embedded in the key members. 
     
     
       19. The fabric-based item defined in  claim 17  wherein each key has a key label and wherein the fabric-based item further comprises light-emitting diodes on the substrate that illuminate the key label. 
     
     
       20. A fabric-based item, comprising:
 a fabric layer having at least one woven layer of insulating warp and weft strands, wherein the woven layer has an array of openings from which the insulating warp and weft strands have been removed and includes woven touch sensor electrodes that extend across the openings; 
 an array of movable members that each overlap a respective one of the openings; and 
 touch sensor circuitry coupled to the touch sensor electrodes. 
 
     
     
       21. The fabric-based item defined in  claim 20  further comprising an array of switches, each switch being overlapped by a respective one of the movable members. 
     
     
       22. The fabric-based item defined in  claim 21  wherein the switches comprise dome switches, the fabric-based item further comprising a printed circuit on which the dome switches are mounted. 
     
     
       23. The fabric-based item defined in  claim 22  wherein the woven touch sensor electrodes comprises wires. 
     
     
       24. The fabric-based item defined in  claim 23  wherein the movable members comprise plastic members with key labels and wherein the wires are embedded in the plastic members. 
     
     
       25. The fabric-based item defined in  claim 20  wherein the openings comprise chemically etched openings.

Description:
This application claims the benefit of provisional patent application No. 62/472,895, filed on Mar. 17, 2017 which is hereby incorporated by reference herein in its entirety. 
    
    
     FIELD 
     This relates generally to fabric-based items, and, more particularly, to fabric-based items having fabric with locally thinned areas. 
     BACKGROUND 
     Weaving and other techniques for intertwining strands of material can be used to form fabric. Fabric is sometimes used in forming structures in electronic equipment. A layer of fabric may, for example, be used to cover the keys in a keyboard. 
     In some keyboards, switches are used to gather input. In devices such as these, the presence of the fabric, switches, and other structures in the keys may place undesired constraints on the size of a keyboard. For example, keyboards may be thicker than desired. 
     SUMMARY 
     An item such as a fabric-based item may have a layer of fabric such as a layer of woven fabric. The fabric layer may include insulating warp and weft strands. Conductive strands may be woven into the fabric layer and may form electrodes for a touch sensor. Touch sensor circuitry may be coupled to the conductive strands. The conductive strands may be formed from insulated wires, bare wires, or other conductive strands. 
     Chemical etching or other processing techniques may be used to form an array of openings in the fabric layer. In each opening, some or all of the insulating warp and weft strands may be removed so that each opening passes partly or fully through the fabric layer and locally thins the fabric layer. 
     Keys may be formed from key members and switches. The key members may have key labels. Light-emitting diodes or other light sources may produce illumination for the key labels. Each key member may overlap a respective opening in the fabric layer. The conductive strands may extend across the openings and may be overlapped by the key members. Each switch may be aligned with a respective one of the key members. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of an illustrative fabric-based item with circuitry in accordance with an embodiment. 
         FIG. 2  is a cross-sectional side view of illustrative fabric in accordance with an embodiment. 
         FIG. 3  is a perspective view of an illustrative fabric-based item such as a keyboard that forms part of a cover for a tablet computer in accordance with an embodiment. 
         FIG. 4  is a top view of an illustrative fabric-based strap for a wrist-watch device in accordance with an embodiment. 
         FIG. 5  is a top view of an illustrative fabric structure with keys in accordance with an embodiment. 
         FIG. 6  is a top view of an illustrative capacitive touch sensor formed from a grid of conductive strands of material that form touch sensor electrodes in accordance with an embodiment. 
         FIG. 7  is a schematic diagram of illustrative equipment involved in forming a fabric-based item in accordance with an embodiment. 
         FIG. 8  is a side view of an illustrative layer of fabric being processed using masking structures in accordance with an embodiment. 
         FIG. 9  is a side view of the illustrative fabric layer of  FIG. 8  after processing to form openings in accordance with an embodiment. 
         FIG. 10  is a side view of illustrative equipment for processing fabric by applying masking material to the fabric in accordance with an embodiment. 
         FIG. 11  is a side view of illustrative equipment for processing fabric by selectively applying etchant to the fabric in accordance with an embodiment. 
         FIG. 12  is a cross-sectional side view of an illustrative fabric layer in accordance with an embodiment. 
         FIG. 13  is a cross-sectional side view of an illustrative fabric layer with embedded conductive strands that have been selectively exposed by forming an opening in the fabric layer in which insulating strands of material such as insulating warp and weft strands in a woven fabric layer have been removed in accordance with an embodiment. 
         FIG. 14  is a cross-sectional side view of an illustrative key member having recesses into which conductive strands such as touch sensor wires have been placed in accordance in accordance with an embodiment. 
         FIG. 15  is a cross-sectional side view of the illustrative key member of  FIG. 14  following encapsulation of the conductive strands within the recesses of the key member in accordance with an embodiment. 
         FIG. 16  is a cross-sectional side view of an illustrative key member having a recess into which a conductive strand such as a touch sensor wire has been placed in accordance with an embodiment. 
         FIG. 17  is a cross-sectional side view of the illustrative key member of  FIG. 16  following deformation of portions of the key member to encapsulate the conductive strand in accordance with an embodiment. 
         FIG. 18  is a cross-sectional side view of an illustrative key member being inserted into an opening in a fabric layer that has exposed conductive strands such as touch sensor wires in accordance with an embodiment. 
         FIG. 19  is a cross-sectional side view the key member of  FIG. 18  following insertion into the opening in accordance with an embodiment. 
         FIG. 20  is a cross-sectional side view of an illustrative molded key member into which a conductive strand in an opening in a fabric layer has been embedded in accordance with an embodiment. 
         FIG. 21  is an exploded cross-sectional side view of an illustrative fabric layer and associated key components in accordance with an embodiment. 
         FIG. 22  is a cross-sectional side view of a portion of an illustrative keyboard formed from the components of  FIG. 21  in accordance with an embodiment. 
         FIG. 23  is a cross-sectional side view of a portion of an illustrative keyboard formed from multiple key members surrounding exposed conductive strands in an opening in a fabric layer in accordance with an embodiment. 
         FIG. 24  is a cross-sectional side view of an illustrative fabric layer that is being masked to form an opening pattern in accordance with an embodiment. 
         FIG. 25  is a cross-sectional side view of a portion of an illustrative device such as a keyboard having perforations or other openings that may be formed using the masking structures of  FIG. 24  in accordance with an embodiment. 
         FIG. 26  is a cross-sectional side view of an illustrative fabric layer having a via that interconnects multiple conductive paths in accordance with an embodiment. 
         FIG. 27  is a cross-sectional side view of a portion of an illustrative device such as a keyboard having a key member mounted above flexible layers in accordance with an embodiment. 
         FIG. 28  is a cross-sectional side view of a portion of an illustrative device having a key member mounted in openings in flexible layers in accordance with an embodiment. 
         FIG. 29  is a cross-sectional side view of a portion of an illustrative device having a key member covered with a fabric layer in accordance with an embodiment. 
         FIG. 30  is a cross-sectional side view in which the inner surface of a layer of a locally-thinned fabric has been provided with a ground plane structure in accordance with an embodiment. 
         FIG. 31  is a cross-sectional side view of a layer of fabric having locally removed portions that have been covered with a material such as metal in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Fabric and other materials may be used in forming fabric-based items. For example, fabric may be used in forming portions of a stand-alone electronic device such as a cellular telephone, tablet computer, wrist-watch device, laptop computer, media player, pendant device, a device embedded in eyeglasses or other equipment worn on a user&#39;s head, or other electronic equipment, may be used in forming a strap, a case, a cover, or other accessory for an electronic device (e.g., a cover or other accessory that includes a keyboard), may be used in forming accessories such as headphones, may be used in forming straps, pockets, walls in a bag, or parts of other enclosures, may be used in forming seating or other furniture for a home or office, may be used in forming a seat, dashboard, steering wheel, seatbelt, or other item in a vehicle, may be used in forming part of an embedded system such as a system in which fabric-based equipment is mounted in a kiosk, may be used in forming wearable items such as a necklace, wrist band, arm band, head band, or other wearable band, shoe, or other item of clothing, may be used in forming a wallet or purse, may be used in forming cushions, blankets, or other household items, may be used in forming toys, may be used in forming other equipment with circuitry, or may be used in forming structures that implement the functionality of two or more of these items. 
     Items such as these may include circuitry for supporting input-output features and other functionality. Items such as these may, for example, include keys. The keys may have associated key switches (e.g., dome switches, etc.) so that key presses on the keys by the fingers of a user may be detected. If desired, capacitive touch sensor circuitry may be incorporated into a fabric-based item. Capacitive touch sensor circuitry may, for example, overlap keys in a keyboard. Keys may be arranged in keyboard arrays or may, in some configurations, be used as stand-alone buttons. In some configurations, circuitry in a fabric-based item may contain a light source for generating light that is viewable by a user of the item. The light may be used as general purpose illumination (e.g., light to illuminate an interior portion of a bag or other enclosure), may be used as light that illuminates a user&#39;s ambient environment (as with a flashlight), may be used to illuminate a symbol or other patterned structure on the surface of a keyboard or other item (e.g., a keyboard key label), may serve as backlight illumination or per-pixel illumination for a display having an array of individually adjustable pixels, may provide illumination for a status indicator (e.g., a one-element or multi-element battery strength indicator, a wireless signal strength indicator, a power status indicator, or other symbol for a status indicator), may support wireless light-based communications (e.g., with external equipment), and/or may be used in other light-based applications. 
     An illustrative fabric-based item is shown in  FIG. 1 . Item  10  may contain fabric that forms all or part of a housing wall for item  10  (e.g., a wall that forms one or more external surfaces for item  10 ), may form internal structures for item  10 , may form cosmetic structures for item  10 , or may form other fabric-based structures. The fabric of item  10  may be soft (e.g., item  10  may have a fabric surface that yields to a light touch), may have a rigid feel (e.g., the surface of item  10  may be formed from a stiff fabric), may be coarse, may be smooth, may have ribs or other patterned textures, may have raised and/or depressed regions formed by embossing or other techniques, and/or may be formed as part of a structure that has portions formed from non-fabric structures of plastic, metal, glass, crystalline materials, ceramics, or other materials. 
     Item  10  may have control circuitry  16 . Control circuitry  16  may include storage and processing circuitry for supporting the operation of item  10 . The storage and processing circuitry may include storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in control circuitry  16  may be used to control the operation of item  10 . The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors and other wireless communications circuits, power management units, audio chips, application specific integrated circuits, etc. 
     Input-output circuitry in item  10  such as input-output devices  18  may be used to allow data to be supplied to item  10  and to allow data to be provided from item  10  to external devices. During operation, control circuitry  16  may use input-output devices  18  to gather input from a user, external equipment, and/or the environment around item  10 . Control circuitry  16  may also use input-output devices  18  to provide output to a user or external equipment. 
     Input-output devices  18  may include switches, buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones, speakers, tone generators, vibrators, cameras, sensors such as touch sensors (e.g., capacitive touch sensors), capacitive proximity sensors, light-based proximity sensors, ambient light sensors, compasses, gyroscopes, accelerometers, moisture sensors, force sensors, data ports, displays, and other input-output devices. Keys, buttons, status indicators, displays, trim structures, and other portions of item  10  may be illuminated. For example, light-emitting diodes, lamps, electroluminescent panels, or other sources of light may be used in illuminating patterned openings. The patterned openings may pass through fabric in item  10  and/or other layers of material and may form symbols (e.g., letters and other alphanumeric characters, icons, etc.) or other illuminated shapes. The symbols or other patterned openings may form labels on keys, buttons, or other input-output devices, may form labels on other illuminated structures, may form trim for a component (e.g., a halo surrounding a key), or may form other suitable illuminated area. 
     Fabric for item  10  may be formed from intertwined strands of material. A cross-sectional side view of an illustrative layer of fabric for item  10  is shown in  FIG. 2 . As shown in  FIG. 2 , fabric  20  may include strands of material such as strands  22  and strands  24 . With one suitable arrangement, fabric  20  may be a woven fabric (e.g., strands  22  may be warp strands and strands  24  may be weft strands). Other arrangements may be used for intertwining strands of material for forming fabric  20  for item  10 , if desired. In general, fabric  20  may be woven, knitted, braided, may be intertwined to form felt, or may contain strands of material that have been intertwined using other intertwining techniques. Fabric  20  may include one or more woven layers or one or more fabric layers formed from other intertwining techniques. If desired, layers of plastic and/or other materials may be coupled to one or more layers of fabric. In some arrangements, fabric  20  may include coatings (e.g., polymer coatings to prevent accumulation of dirt, materials that serve as moisture barrier layers, wear resistant coatings, transparent coatings such as patterned translucent coatings, etc.). These coating materials may penetrate into fabric  20  and/or may form layers on the inner and/or outer surfaces of fabric  20 . 
     The strands of material that form fabric  20  may include insulating strands (e.g., polymer yarn, etc.) and conductive strands (e.g., bare wire and/or wire coated with insulation). The strand of material be monofilaments, may be multifilament strands (sometimes referred to herein as yarns, threads, or multifilament wire), may be formed from metal (e.g., metal monofilaments and/or yarns formed from multiple monofilament wires), may be formed from dielectric (e.g., polymer monofilaments and yarns formed from multiple polymer monofilaments), may include dielectric cores covered with conductive coatings such as metal (e.g., metal coated dielectric monofilaments and yarns of metal coated polymer-core monofilaments may be used to form conductive monofilaments and conductive yarns, respectively), may include outer insulating coatings (e.g., coatings of polymers or other dielectrics may surround each metal-clad polymer monofilament or each collection of metal-clad polymer monofilaments in a yarn, polymer insulation may enclose a multifilament metal wire, etc.), or may be other suitable strands of material for forming fabric. 
     As shown in the illustrative configuration of fabric  20  of  FIG. 2 , for example, strands such as strands  22  and  24  may be formed from strands of yarn that each contain multiple monofilaments  26 . Configurations in which the fabric is formed from yarns (e.g., multifilament strands of material that are insulating or that contain metal wires and/or metal coatings on polymer monofilaments to render the yarns conductive) may sometimes be described herein as an example. This is, however, merely illustrative. Fabric  20  may be formed using monofilaments, multifilament strands of material (yarns), combinations of these arrangements (e.g., fabric with polymer coated wires interspersed with insulating yarn), etc. The diameter of strands  22  and  24  that are formed from yarns containing multiple monofilaments may be, for example, 0.25 mm, may be 0.1 to 0.5 mm, may be more than 0.2 mm, may be less than 2 mm, or may be any other suitable diameter (width). 
       FIG. 3  is a perspective view of fabric-based item  10  in an illustrative configuration in which fabric-based item  10  serves as a cover for an electronic device such as a tablet computer. As shown in  FIG. 3 , item  10  may include an upper surface such as upper surface  32  with an array of keys (e.g., keys in a QWERTY keyboard, etc.). Folded portion  34  of item  10  may form a support structure for electronic device  36 . Device  36  may be a tablet computer with a display such as display  38  mounted in a housing such as housing  42 . Input-output devices such as button  40  may be provided in device  36  to gather user input. Device  36  may communicate with item  10  wirelessly or through a wired connection. The cover configuration for  FIG. 3  (e.g., an arrangement in which item  10  forms a keyboard and a protective enclosure for tablet computer  36  or other electronic equipment) is merely illustrative. Other types of fabric-based item may include keys  30 , foldable portions such as portion  34 , etc. 
       FIG. 4  is a diagram of item  10  in an illustrative configuration in which item  10  forms part of a wrist-watch device (e.g., device  43 ). Device  43  may have a main unit such as unit  44  with a display such as display  46 , button  48 , a touch sensor (e.g., a touch sensor in display  46 ) and other input-output circuitry. Unit  44  may be coupled to item  10 , which forms an integral or separable strap for device  43 . Item  10  may have one or more regions such as regions  50  in which light-emitting diodes or other light sources emit light. Openings in a fabric layer in item  10  (e.g., perforations, etc.) may be used in regions  50  to from patterns of light-emitting structures (e.g., passageways for emitted light) and may be patterned to form symbols, a two-dimensional array of pixels that form a display in regions  50 , and/or other openings. 
       FIG. 5  is a top view of a portion of an illustrative fabric-based item (item  10 ) having keys  30 . Keys  30  may have key members (sometimes referred to as key caps) with key labels  52  (sometimes referred to as glyphs or key label patterns). Key labels  52  may be formed from ink or other material, from portions of a fabric layer that have been woven differently than adjacent portions of the fabric layer, may be formed from part of a molded plastic member, may be formed from etched or machined structures, may be formed from openings in a fabric layer or other layer, may be illuminated or may not be illuminated, and/or may have other configurations. Surface  32  and/or keys  30  may be formed from fabric. As an example, surface  32  may be a fabric layer that forms an outer surface for a keyboard housing or other electronic device housing, (fabric-based item housing) and keys  30  may be formed from plastic (polymer). Other configurations (e.g., configurations in which keys  32  include fabric and/or are covered by fabric) may also be used, if desired. Keys  30  may be arranged in a QWERTY keyboard layout (e.g., in configuration in which item  10  forms a keyboard such as a keyboard in a removable device cover and/or other fabric-based item), may form a keypad (e.g., a numeric keypad, a keypad with symbols such as letters, numbers, and other symbols, etc.), may form one or more buttons (e.g., buttons on the front or side of a watch strap or other portion of a watch, a cellular telephone cover or other portion of a cellular telephone or cellular telephone accessory), may form part of a bag, clothing, seat, etc. 
     It may be desirable to incorporate one or more touch sensors into item  10 . As an example, it may be desirable to form a capacitive touch sensor in item  10 . An illustrative two-dimensional capacitive touch sensor of the type that may be incorporated into item  10  is shown in  FIG. 6 . As shown in  FIG. 6 , touch sensor  56  may include touch sensor electrodes  58 . Electrodes  58  may include conductive paths such as drive lines D and sense lines S. Lines D and S may be formed from multifilament wires (e.g., multifilament copper wire with polymer insulation) or other conductive strands of material. The conductive strands may be woven into a fabric layer formed from insulating warp and weft strands (as an example). Touch sensor  56  may form a track pad, a touch-sensitive slider or button, a two-dimensional touch sensitive input area on a shirt or other item of clothing, a touch sensitive input device for a wearable fabric band, a touch sensitive portion of a removable electronic device case (cover), and/or other suitable touch sensor structures. 
     The conductive strands forming electrodes  58  may be arranged in a grid pattern (a pattern in which lines D run vertically along the Y-axis and in which lines S run horizontally along the X-axis) or other suitable pattern and may be embedded in a layer of fabric such as fabric layer  20  ( FIG. 2 ). Keys such as key  30  and electrodes  58  may overlap. For example, electrodes  58  may form a two-dimensional touch sensor that overlaps some or all of keys  30  in a QWERTY keyboard array or other array of keys  30 . Touch sensor circuitry  60  may supply drive signals to drive lines D while monitoring sense lines S. During operation of sensor  56 , circuitry  60  may process the signals on electrodes  58  to detect capacitance changes in electrodes  58  due to the presence of a user&#39;s finger or other external object (see, e.g., finger  62 ). Circuitry  60  may process the capacitance measurements to determine the location of finger  62  (e.g., a coordinate X, Y that overlaps or that does not overlap a key  30  in the example of  FIG. 6 ). Keys  30  may have dome switches or other input devices to sense key presses from finger  62  while sensor  56  is used to gather touch input from finger  62 . If desired, dome switches or other input devices for keys  30  may be omitted and key press information gathered by an overlapping touch sensor such as touch sensor  56 . Configurations in which touch sensor  56  does not overlap keys  30  may also be used in fabric-based item  10 . 
     Illustrative equipment for forming fabric-based item  10  is shown in  FIG. 7 . As shown in  FIG. 7 , equipment  62  may include material removal tools  64 . Tools  64  may include laser-based equipment, heat-producing tools, chemical processing tools (e.g., tools for applying liquid chemicals to the structures of fabric-based item  10  such as inkjet printers, drums, screen printing equipment, spraying equipment, dripping equipment, pad printing tools, etc.), equipment for cutting, machining, stamping, drilling, and sawing, and/or other machining equipment, and/or other processing equipment. Intertwining equipment  66  may include equipment for intertwining strands of material by weaving, knitting, braiding, or other intertwining techniques. For example, equipment  66  may include a weaving tool, a knitting tool, a braiding tool, and/or other equipment for forming one or more fabric layers in item  10 . Molding equipment  68  may be used in molding plastic structures in item  10  (as an example). Equipment  62  may also include additional tools  70  for processing and assembling item  10  (e.g., tools for using adhesive and/or fasteners to couple structures together, tools for soldering and welding components, inspection equipment, etc.). 
     Openings may be formed in one or more fabric layers for item  10  using equipment such as equipment  64  of  FIG. 7 . Consider, as an example, the arrangement of  FIGS. 8 and 9 . Initially, a mask such as mask  72  may be applied to fabric layer  20 . Mask  72  may be applied to outer surface  78  and, as indicated by illustrative mask  72 ′, may be applied to inner surface  80  of layer  20 . Masks such as masks  72  and  72 ′ may be formed from patterned structures (e.g., stencils formed from plastic, metal, ceramic, glass, etc.) and/or may be formed from polymer coating layers (e.g., photolithographically patterned polymer coatings, polymer coatings or other coatings patterned by pad printing, inkjet printing, screen printing, etc.). While masks  72  and  72 ′ are in place, layer  20  can be exposed to a chemical etchant (gaseous, liquid, etc.). The etchant may be, for example, a solvent that dissolves polymer strands of material (e.g., insulating warp and weft strands in a woven fabric) and/or other strands of material in layer  20  without removing mask  72 . 
     Masks  72  and  72 ′ have openings such as opening  74  that allow layer  20  to be exposed to etchant in a desired pattern during etching operations. Following etching, masks  72  and  72 ′ may be removed (e.g., by pulling away metal stencils or other mechanical masks, by using heat and/or solvents to strip polymer coating masks, etc.).  FIG. 9  is a cross-sectional side view of illustrative layer  20  o  FIG. 8  following etching and removal of masks  72  and  72 ′. 
     During etching, exposed portions of layer  20  in openings  74  of masks  72  and  72 ′ are etched away by the etchant, thereby forming locally thinned regions in layer such as fabric layer openings  82 . Openings  82  may penetrate partway through layer  20  or may pass entirely through layer  20  (see, e.g., dashed lines  84  in the example of  FIG. 9 ). 
     Illustrative roll-to-roll processing equipment for etching openings  82  in fabric layer  20  or otherwise forming locally thinned regions in fabric layer  20  is shown in  FIG. 10 . As shown in  FIG. 10 , equipment  86  may have a dispensing roller such as roller  88  that dispenses fabric layer  20  and may have a take-up roller such as roller  102  that receives layer  20 . Mask application station  90  includes a bath of masking material  92  (e.g., liquid polymer mask). Roller  94  has patterned pads  96  that receive coating  92  and apply coating  92  to the surface of layer  20  as rollers (drums)  88  and  94  rotate. This forms a desired patterned mask  72  (and, if additional rollers are used, mask  72 ′) on layer  20 . Layer  20  and the masks on layer  20  that were deposited at station  90  pass through etching station  92 . Etching station  92  includes etchant  94  (e.g., liquid solvent, etc.) that etches openings  82  ( FIG. 9 ) into fabric layer  20 . Following etching, equipment  98  (e.g., a bath, spraying equipment, etc.) may be used to apply mask stripping material  100  (e.g., a polymer solvent or other mask stripper) to layer  20  to remove mask  72  (and  72 ′ if present). Layer  20  may then be stored on take-up roller  102 . 
     In the illustrative configuration of  FIG. 11 , roll-to-roll etching equipment  104  is being used to pattern openings  82  into fabric layer  20 . Roller  106  may be used to dispense layer  20 . Take-up roller  108  may be used to receive layer  20  after passing through etching station  110 . Etching station  110  may include an etchant bath such as etchant  112  (e.g., liquid solvent) that is applied in a desired pattern of openings  82  to layer  20  using patterned pads  114  on roller  116 . If desired, ink-jet printing equipment, screen printing equipment, or other equipment for supplying patterned etchant  112  to layer  20  may be used. The configuration of  FIG. 11  is illustrative. 
       FIG. 12  is a cross-sectional side view of fabric layer  20  showing how fabric layer  20  may include multiple layers (e.g., layers  20 - 1 ,  20 - 2 ,  20 - 3 ,  20 - 4 ,  20 - 5 , more layers, fewer layers, etc.). One or more of the layers of fabric layer  20  may include conductive strands of material such as the conductive strands of material used in forming electrodes  58  of  FIG. 6 . As an example, layer  20 - 3  may include a grid of embedded conductive D and S lines (see, e.g., touch sensor electrodes  58  of  FIG. 6 ) that are formed from metal wire (e.g., single-filament or multifilament wire that is bare and/or that has insulating coating material such as a polymer coating on each filament or set of filaments). 
     The solvent used to remove the material of layer  20  to form openings such as openings  82  of  FIG. 9  may be used to expose capacitive sensor wires or other embedded conductive strands. As shown in  FIG. 13 , for example, fabric layer  20  may include one or more embedded conductive strands of material such as conductive strands  118 . Strands  118  may form a grid of S and D wires for electrodes  58  of touch sensor  56  and/or may form interconnect lines, sensor structures, and/or other conductive paths in fabric  20 . Strands  118  may be embedded into layer  20  (e.g., into fabric with insulating warp and weft fibers) using weaving or other techniques (e.g., to form a layer such as layer  20 - 3  that is embedded between outer layers  20 - 1  and  20 - 2  and inner layers  20 - 4  and  20 - 5  in the example of  FIG. 12 ). During fabric removal operations (e.g., etching operations using equipment of the type shown in  FIG. 10 or 11  and/or other operations using material removal tools  64  of  FIG. 7 ), openings such as opening  82  of  FIG. 13  may be formed that locally thin layer  20  and thereby expose strands  118 . Opening  82  may pass entirely through layer  20  (as shown in  FIG. 13 ) and/or may have portions that extend only partway through layer  20  (e.g., to locally thin layer  20  without passing entirely through layer  20 ). In configurations in which opening(s)  82  pass only partially through layer  20 , strands  118  may or may not be exposed by the presence of the opening(s). 
     The removal of material to form opening(s)  82  may reduce the thickness of layer  20  and may thereby help reduce the thickness of portions of item  10  (e.g., the thickness of the portions of item  10  overlapped by key members for keys  30 , etc.). For example, removing portions of layer  20  to form openings  82  to expose conductive strands such as strands  118  of  FIG. 13  (e.g., strands for forming touch sensor electrodes  58 ) may allow strands  118  to be incorporated into keys  30  while minimizing the thickness of item  10 . Strands  118  may, for example, be embedded in key members (sometimes referred to as key caps or key structures) such as illustrative key member  30 M of  FIG. 14  or may be embedded in other dielectric structures (e.g., movable dielectric structures such as movable buttons members formed from plastic or other material for stand-alone buttons for a case, electronic device, or other fabric-based item, static dielectric structures such as structures associated with portions of a trackpad, housing structures, structures with haptic feedback devices, etc.). Configurations in which strands  118  and/or other conductive structures are embedded within a key member that forms part of a keyboard may sometimes be described herein as an example. This is, however, merely illustrative. Members such as member  30 M may, in general, be any suitable structures formed from plastic, glass, ceramic, or other dielectric and may be associated with any suitable types of item  10 . 
     In the example of  FIG. 14 , the lower (inner) surface of key member  30 M has been provided with recesses (grooves)  120 . Recesses  120  may receive one or more strands  118  (e.g., strands  118  that have been exposed within an opening  82  in layer  20  and that extend across that opening). As shown in  FIG. 15 , encapsulant  122  (e.g., epoxy or other polymer, etc.) may be used to hold strands  118  within recesses  120 . This type of arrangement allows touch sensor electrodes  58  or other structures formed from strands  118  to be incorporated into keys  30  without enhancing the thickness of keys  30  (e.g., while maintaining a given thickness T of key member  30 ). 
     Another illustrative technique for incorporating touch sensor electrodes or other strands  118  into key members  30 M is shown in  FIGS. 16 and 17 . Initially, strands  118  may be inserted into recesses  120  of key member  30 M ( FIG. 16 ). Heated tool  126  may then press against portions  30 M′ of member  30 M in direction  124  ( FIG. 16 ). This softens portions  30 M′ and allows portions  30 M′ to deform and thereby cause strands  118  to become embedded in member  30 M, as shown in  FIG. 17 . 
     If desired, strands  118  (e.g., touch sensor electrodes  58 ) may be embedded in key member  30  by heating strands  118  sufficiently that they cut into member  30 M as member  30 M is moved into opening  82  in fabric layer  20 , as shown in  FIGS. 18 and 19 .  FIG. 18  shows how key member  30 M may be aligned with opening  82  and moved in direction  128  after heating strands  118  (e.g., using a laser, hot bar tool, oven, lamp, ohmic heating, or other heating arrangement).  FIG. 19  shows how strands  118  may be embedded within the plastic (polymer) or other material of key member  30 M of  FIG. 18  after member  30 M is moved in direction  128  to cause strands  118  to melt and thereby cut into key member  30 M. 
       FIG. 20  shows how key member  30 M may be formed by molding a material such as plastic around strands  118  in opening  82  of layer  20 . During molding operations, molten plastic may be injected into a cavity in mold  130  and/or mold  130  may apply heat and/or pressure to mold key member  30 M into a desired shape around strands  118 . The molding process may, if desired, cause portions of key member  30 M and/or other plastic structures to penetrate into portions of fabric layer  20  (e.g., while embedding strands  118  within member  30 M and/or other key structures). 
       FIG. 21  is an exploded cross-sectional side view of an illustrative key for item  10 . In the example of  FIG. 21 , key  30  has a key member such as key member  30 , has an inner key support such as key support (member)  30 L, and has a switch such as dome switch  132 . Dome switch  132  may be mounted to a printed circuit board (e.g., a rigid printed circuit board formed from fiberglass-filled epoxy or a flexible printed circuit formed from a sheet of polyimide or other flexible polymer layer) and/or other substrate such as illustrative printed circuit  134 . During operation, a user may press inwardly on member  30 M, which may press (bias) structure  30 L against dome switch  132  and thereby close switch  132 . Processing circuitry  16  can detect the closing of switch  132  and can take suitable action in response to this detected key press event. The compression of dome switch  132  and, if desired, ancillary biasing structures, may create an outwardly directed restoring force that forces structure  30 L and member  30 M upwards following release of key member  30 M by the user. An optional key support grid (sometimes referred to as a key web) such as support structure  136  may have an array of openings for receiving respective key structures such as key member  30 M and/or key support  30 L, thereby forming an array of keys  30  for item  10 . If desired, structures  136  can be omitted. Key structures such as key support  30 L may also be omitted in some configurations (e.g., in arrangements in which key member  30 M provides sufficient support for key  30 ). 
     As shown in the illustrative cross-sectional side view of  FIG. 21 , the formation of an opening such as opening  82  that passes partly or completely through fabric layer  20  helps locally thin layer  20  (e.g., from a thickness TD to a reduced thickness). This removed thickness helps minimize the overall thickness of the stack-up of key  30 . In particular, the presence of opening  82  may help remove thickness TD from the height (thickness in dimension Z in the example of  FIG. 21 ) of key  30 . As an example, if strands  118  are about 0.075 mm in diameter and if fabric layer  20  in portions of layer  20  without opening  82  has a thickness TD of about 0.2 mm, the formation of openings  82  in layer  20  in the portions of layer  20  that overlap key members  30 M can reduce the thickness of keys  30  by about 0.2 mm. This can help minimize the thickness and size of fabric-based item  10 . In general, key member  30 , support  30 L, fabric  20 , and strands  118  may have any suitable sizes (e.g., 0.001-10 mm, more than 0.01 mm, more than 0.1 mm, more than 0.5 mm, less than 5 mm, less than 1 mm, less than 0.1 mm, less than 0.01 mm, etc.). The use of strands  118  with a thickness (diameter) of 0.075 mm and a fabric layer  20  with a thickness of 0.2 mm is merely illustrative. 
       FIG. 22  is a cross-sectional side view of key  30  following assembly of key  30  of  FIG. 21 . In the example of  FIG. 22 , conductive strands  118  have been embedded into key member  30 M, as described in connection with  FIGS. 14-20 . Strands  118  may have relatively small diameters relative to the thickness of layer  20  (e.g., the diameter of strands  118  may be 1/10 or less of the thickness of layer  20 ), so that the presence of strands  118  within key member  30 M will not significantly increase the thickness of key member  30 M. The formation of opening  82  in layer  20  and the embedding of strands  118  within key member  30 M therefore can help reduce the overall stack-up thickness of keys  30 . 
     The selective fabric removal and strand embedding techniques of  FIGS. 14-22  may be used to embed strands  118  in key member  30 M, in key support  30 L, and/or other portions of key  30  and/or item  10 . If desired, strands  118  may be sandwiched between respective portions of key  30 . As shown in  FIG. 23 , for example, key  30  may be formed by attaching key member  30  to key support  30 L with adhesive  138  (e.g., a thermoplastic adhesive, a thermoset adhesive, an adhesive formed from one or more polymers, etc.). By interposing strands  118  between member  30 M and structure  30 L in opening  82  of fabric layer  20  while ensuring that the opening  82  in layer  20  that receives structures  30 M and  30 L is partly or fully free of the insulating strands forming fabric  20 , the thickness of key  30  may be reduced. If desired, layer  20  may be only partially thinned in opening  82  (e.g., opening  82  may pass only partway through layer  20 ). The configurations of  FIGS. 21-23  in which opening  82  passes through layer  20  so that only strands  118  and not any other fabric strands remain in opening  82  are presented as examples. 
       FIG. 24  is a cross-sectional side view of an illustrative fabric layer in which masks  72  and  72 ′ are being used to form a patterned array of relatively small openings  74 . Following formation of corresponding openings  82 P in layer  20  as shown in  FIG. 25  (e.g., using etching in the areas of layer  20  that are exposed through openings  74  of  FIG. 24  or using other techniques such as laser processing or cutting techniques that do not involve use of masks  72  and  72 ′, and/or using other opening formation techniques with tools such as tools  64  of  FIG. 7 ), masks  72  and  72 ′ (if present) may be removed and layer  20  assembled into a system. As an example, layer  20  may be mounted above a light source such as light-emitting diodes  140  on printed circuit  134  adjacent to dome switch  132 , as shown in  FIG. 25 . With this type of arrangement, openings  82 P may have a pattern that forms a key label (see, e.g., key labels  52  of  FIG. 5 ) or other symbol (e.g., a trim surrounding a key). If desired, openings  82 P may be patterned to form an array of pixel in a display. Each pixel may be illuminated with light  144  from a corresponding light-emitting diode  140  in an array of light-emitting diodes  140 . 
     As shown in  FIG. 25 , material  142  (e.g., transparent plastic that is clear or hazy to help homogenize light  144  from light-emitting diodes  140 ) may be formed over openings  82 P. Material  142  may be used to seal openings  82 P, may form some or all of a key (e.g., part of key member  30 M), and/or may form other structures in item  10 . For example, material  142  may be overlapped by a separate key member  30 M (e.g., a clear key member or other key member may be coupled to material  142  using adhesive, etc.). Illuminated structures in item  10  that use openings  82 P may be formed in areas  50  of  FIG. 4 , in portions of keys  30  (e.g., to form key labels  52  of  FIG. 5 ), may be used to form decorative halos around keys  30  and/or other decorative trim in item  10 , and/or may be used in forming other structures in item  10 . 
     As shown in  FIG. 26 , openings in fabric layer such as illustrative opening  82 V may be used to form conductive vias in fabric layer  20 . Fabric layer  20  may, as an example, include conductive pathways such as pathways  118 P. Layer  20  may have one or more layers of fabric and/or other materials (plastic, etc.). As an example, layer  20  may include three fabric layers  20 A,  20 B, and  20 C. Conductive pathways  118 P may be formed from conductive strands (e.g., wires woven into one or more of the layers of fabric  118 ) or may include other conductive materials. In the example of  FIG. 26 , conductive material  156  has been placed in an opening in layer  20  to form via  82 V. Via  82 V electrically couples a conductive path  118 P in layer  20 A to a conductive path  118 P in layer  20 B. Via  82 V (or pad-shaped extensions of via  82 V on the upper or lower surfaces of layer  20 ) can be electrically coupled to electrical components such as component  150 . Component  150  (see, e.g., control circuitry  16  and devices  18  of  FIG. 1 ) may have one or more contacts such as solder pad  152  and may be coupled to via  82 V using conductive material  154 . Conductive material  154  and/or conductive material  156  may be solder, conductive adhesive, metal paint (e.g., silver paint), metal deposited using physical vapor deposition, electroplating, and/or other deposition techniques, and/or other conductive material. 
     In the example of  FIG. 27 , item  10  includes keys such as key  30  that are formed from key members  30 M on a layer of material (layer  160 ) formed from multiple sublayers. Layers  160  may include traces formed from a patterned conductive layer  118 L and one or more dielectric layers such as insulating layers  162 ,  164 , and  166 . Layer  118 L may be formed from silver paint, physical vapor deposition metal and/or electroplated metal, and/or other metal or other conductive materials. For example, layer  118 L may include metal traces patterned to form capacitive touch sensor electrodes such as electrodes  58  of  FIG. 6  to form a touch sensor that overlaps keys  30  in item  10 . Layer  162  may be a protective outer polymer layer such as a layer of polyurethane or other suitable polymer. Layer  164  may be a thermoplastic elastomer (e.g., an elastomeric polymer such as a polyester polymer or other polymer that is stretchy). Layer  166  may be a polyurethane layer or other polymer layer. 
     Layers  162 ,  164 , and  166  (and, if desired, other insulating layers in layer  160 ) may help to protect traces  118 L (e.g., electrodes  58 ) from environmental exposure (e.g., moisture, etc.) and thereby form an environmental barrier for traces  118 L. Electrodes  58  may be used to form a touch sensor that is overlapped by keys  30  (and, if desired, by the portions of layer  160  that do not have keys  30 ). Key member  30 M may be a plastic (polymer) member or other structure that serves as a labeled key structure for key  30  (e.g., a structure that may be pressed by a user). A dome switch may, if desired, be mounted under layer  160  in alignment with key member  30 M. Configurations in which key input is gathered by making capacitive touch sensor measurements with electrodes  58  formed from patterned metal traces  118 L under key members  30 M may also be used. If desired, layer  160  may have sufficient flexibility to allow key member  30 M to travel inwardly and outwardly along dimension Z as a user presses and releases key member  30 M. move up and w, while allowing key member  30 M (e.g., a plastic member coupled to layer  160  using fasteners, adhesive, etc.) to flex up and down in dimension Z (if d 
       FIG. 28  shows how openings  170  may be formed in layers  162  and  164 . With this type of arrangement, member  30 M may be placed closer to patterned metal traces (conductive traces)  118 L (e.g., touch sensor electrodes  58 ) and the thickness of keys  30  and item  10  in dimension Z may be reduced. 
     If desired, one or more of the layers of layers  160  of  FIGS. 27 and 28  may be formed from fabric layer  20 . For example, fabric layer  20  may be stacked on layer  162  to provide item  10  with a fabric outer surface. Configurations in which the structures of  FIGS. 27 and 28  are formed in electronic devices without fabric may also be used. 
       FIG. 29  is a cross-sectional side view of a portion of an illustrative item having a key member covered with a fabric layer. As shown in  FIG. 29 , key member  30 M for key  30  may be received within an opening in fabric  20 . This allows conductive strands  118  to penetrate into key member  30 M during fabrication. An additional layer of fabric such as fabric layer  20 T may, if desired, cover some or all of key members such as key member  30 . Layer  20 T may have a locally thinned region that receives the upper portion of key member  30 . Chemical etching or other thinning techniques may be used in forming this locally thinned region. If desired, conductive paths in fabric layer  20 T such as conductive strand  118 ′ may be used as touch sensor electrodes and/or other signal paths. In this type of arrangement, conductive strands  118  may optionally be omitted. Configurations in which layer  120  is formed by a non-fabric material and/or in which upper layer  20 T is formed by a non-fabric cosmetic coating layer may also be used. 
     As shown in  FIG. 29 , haptic devices such as haptic device  178  may be coupled to member  30 M to provide haptic feedback (e.g., a vibration or other haptic response to a detected touch input to a touch sensor overlapping member  30 M that is formed from paths  118  and/or  118 ′). Haptic output device  178  may have piezoelectric actuators, vibrators, electromagnetic actuators, and/or other haptic components for providing member  30 M with haptic output. 
       FIG. 30  is a cross-sectional side view of a layer of fabric having locally removed portions that have been covered with a material such as metal. In the example of  FIG. 30 , region  174  of fabric layer  20  has been locally thinned (e.g., by chemically etching to remove a portion of layer  20  on the inner side of layer  20  in the example of  FIG. 30 ). Material  176  has been formed in a patch that covers some or all of the area associated with locally-thinned region  174 . Material  176  may be, for example, a polymer, a metal, and/or other material. With one illustrative configuration, material  176  is a layer of metal (e.g., metal deposited using physical vapor deposition, electrochemical deposition techniques such as electroplating, metal paint printing, etc.) and can serve as a ground plane or other structure. A key member or other structure may also be placed in openings such as the opening formed by locally-thinned region  174 . 
     As shown in  FIG. 31 , fabric layer  20  may have locally-thinned regions such as grooves, patches, and/or other areas that are partly or completely filled with material  176 . The locally-thinned regions on fabric layer  20  may be formed by chemical etching and/or other material removal techniques. Material  176  may be polymer, metal, and/or other suitable material. As an example, material  176  may be metal (e.g., metal deposited using physical vapor deposition, electrochemical deposition techniques such as electroplating, metal paint printing, etc.) and can serve as a signal conductor (e.g., signal routing paths, ground plane structures, etc.) and/or as cosmetic structures. 
     The foregoing is merely illustrative and various modifications can be to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20170714
Publication Date: 20220405
Grant Date: 20220405
Priority Date: 20170317
Inventors: WANG, PAUL X.
ZIMMERMAN, AIDAN N.
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F1/1669", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/163", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1628", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B2262/128", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B2457/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B2307/202", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B2262/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B2255/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B5/263", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B2262/103", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B5/024", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B2255/26", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B3/263", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D15/67", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D1/0088", "inventive": true, "first": true, "tree": "[]"}, {"code": "D03D15/25", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B27/12", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1675", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1662", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D15/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B3/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "D03D15/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "B32B27/12", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1662", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1675", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B3/00", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 80934069