PATENT DOCUMENT

Publication Number: US-9263790-B2
Application Number: US-201514736992-A
Country: US
Kind Code: B2

Title: Structures for shielding and mounting components in electronic devices

Abstract:
An electronic device may be provided with a conductive housing. An antenna window structure may be formed in an opening in the housing. The antenna window structure may have an antenna support structure that is attached to the conductive housing and that supports antenna structures. An antenna window cap may be mounted in the opening and attached to the antenna support structure with liquid adhesive. Alignment structures may be provided in the antenna support structure. An antenna support plate with mating alignment structures may be used in attaching the antenna structures to the antenna support structures. Metal shielding structures may be used to provide electromagnetic shielding. A shielding wall may be formed from a sheet metal structure supported by a plastic support structure. A flexible metal shielding foil layer may be welded to the shielding wall using a sacrificial plate.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 an antenna support structure having at least one alignment feature; 
 an antenna support plate having at least one alignment feature that mates with the alignment feature of the antenna support structure; 
 antenna structures mounted on the antenna support plate; and 
 an electronic device housing having at least one rib, wherein the antenna support structure comprises a rib that is configured to bear against the rib of the electronic device housing to align the antenna support structure with respect to the electronic device housing. 
 
     
     
       2. The electronic device defined in  claim 1  wherein the alignment feature of the antenna support structure comprises an opening and wherein the alignment feature of the antenna support plate comprises an alignment post that is configured to mate with the opening. 
     
     
       3. The electronic device defined in  claim 2  further comprising a biasing structure that biases the antenna support plate away from the antenna support structure. 
     
     
       4. The electronic device defined in  claim 3  wherein the biasing structure comprises foam. 
     
     
       5. The electronic device defined in  claim 1  wherein the antenna support structure comprises a plastic structure with a plurality of air-filled cavities. 
     
     
       6. An electronic device, comprising:
 an antenna support structure with a plurality of air-filled cavities, wherein the antenna support structure comprises at least one alignment feature in an air-filled cavity of the plurality of air-filled cavities; 
 a plate having at least one alignment feature that mates with the alignment feature of the antenna support structure; and 
 antenna structures mounted on the plate. 
 
     
     
       7. The electronic device defined in  claim 6  wherein the at least one alignment feature of the antenna support structure comprises an opening. 
     
     
       8. The electronic device defined in  claim 7  wherein the opening has first and second opposing sides, the electronic device further comprising:
 a first biasing structures that is formed on the first side of the opening; and 
 a second biasing structures that is formed on the second side of the opening. 
 
     
     
       9. The electronic device defined in  claim 8  wherein the at least one alignment feature of the plate comprises a post that protrudes through the opening. 
     
     
       10. The electronic device defined in  claim 9  wherein each of the first and second biasing structures comprises foam. 
     
     
       11. The electronic device defined in  claim 6  wherein the antenna support structure has first and second opposing sides, wherein the plate and antenna structures are formed on the first side of the antenna support structure, and wherein a dielectric window is formed on the second side of the antenna support structure. 
     
     
       12. The electronic device defined in  claim 6  wherein the antenna structures are parallel to and in direct contact with the plate. 
     
     
       13. The electronic device defined in  claim 12  wherein the plate comprises first and second holes, and wherein the antenna structures comprise first and second holes that overlap the first and second holes of the plate. 
     
     
       14. An electronic device, comprising:
 a support structure, wherein the support structure comprises a plurality of ribs that form a plurality of air-filled cavities, and wherein the support structure has a top surface; 
 an antenna plate adjacent to the top surface of the support structure, wherein the antenna plate has an alignment post, and wherein the alignment post protrudes into an air-filled cavity of the support structure; and 
 a flexible printed circuit mounted on the antenna plate. 
 
     
     
       15. The electronic device defined in  claim 14  wherein the flexible printed circuit contains antenna traces. 
     
     
       16. The electronic device defined in  claim 15  wherein the antenna plate is interposed between the support structure and the flexible printed circuit. 
     
     
       17. The electronic device defined in  claim 14  further comprising a biasing structure that is in direct contact with a rib of the plurality of ribs. 
     
     
       18. The electronic device defined in  claim 14  further comprising:
 a housing, wherein the housing comprises first and second opposing surfaces, wherein the second surface forms a portion of an exterior of the electronic device, and wherein the housing comprises a portion that protrudes from the first surface. 
 
     
     
       19. The electronic device defined in  claim 18  wherein the support structure comprises a protruding portion, and wherein the protruding portion of the support structure is in direct contact with the portion that protrudes from the first surface of the housing.

Description:
This application is a division of patent application Ser. No. 13/524,997, filed Jun. 15, 2012, which claims the benefit of provisional patent application No. 61/652,796, filed May 29, 2012, both of which are hereby incorporated by reference herein in their entireties. This application claims the benefit of and claims priority to patent application Ser. No. 13/524,997, filed Jun. 15, 2012, and provisional patent application No. 61/652,796, filed May 29, 2012. 
    
    
     BACKGROUND 
     This relates to electronic devices and, more particularly, to antenna structures and electromagnetic shielding structures for electronic devices. 
     Electronic devices often contain wireless circuitry. For example, cellular telephone transceiver circuitry and wireless local area network circuitry may be provided to allow a device to wirelessly communicate with external equipment. Antenna structures may be used in transmitting and receiving wireless signals. 
     Devices may also contain displays and other circuits that may interfere with wireless circuitry. To properly ground antenna structures and to provide electromagnetic shielding to reduce the impact of potentially harmful electromagnetic interference, it may be desired to incorporate electromagnetic shielding structures in an electronic device. Care should be taken, however, to avoid structures that are unnecessarily bulky, that provide unsatisfactory grounding, or that provide inadequate suppression of electromagnetic interference. 
     It would therefore be desirable to be able to provide improved structures for mounting antennas in electronic devices and providing electromagnetic shielding. 
     SUMMARY 
     An electronic device may be provided with a conductive housing. An antenna window structure may be formed in an opening in the housing. The antenna window structure may have an antenna support structure that is attached to the conductive housing. Antenna structures such as antenna structures formed from traces on a printed circuit may be mounted on the antenna support structure. An antenna window cap may be mounted in the opening of the conductive housing. The antenna window cap may be attached to the antenna support structure with liquid adhesive that allows the antenna window cap to lie flush with an exterior surface of the conductive housing during adhesive curing operations, thereby improving flushness. 
     Alignment structures may be provided in the antenna support structure. An antenna support plate with mating alignment structures may be used in attaching the antenna structures to the antenna support structures. Ribs on the antenna support structure may serve as alignment features that bear against corresponding rib-shaped alignment features on the conductive housing. 
     Metal shielding structures may be used to provide electromagnetic shielding in the electronic device. Shielding walls may be formed from sheet metal structures supported by a plastic support structure. End portions of the shielding walls may be embedded within the plastic support structure during an insert molding process. 
     A flexible shielding layer formed from a thin metal sheet may be welded to a shielding wall. The thin metal sheet may have a thickness of less than 20 microns. To prevent damage during welding, a sacrificial plate may be incorporated into the welded structure. Conductive structures such as springs on printed circuits and conductive foam may be used in connecting shielding structures to a conductive electronic device housing. 
     Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front perspective view of an illustrative electronic device of the type that may contain mounting, grounding, and shielding structures in accordance with an embodiment of the present invention. 
         FIG. 2  is a rear perspective view of the electronic device of  FIG. 1  in accordance with an embodiment of the present invention. 
         FIG. 3  is a schematic diagram of an illustrative electronic device in accordance with an embodiment of the present invention. 
         FIG. 4  is a perspective view of an illustrative antenna support structure and an associated flexible printed circuit antenna structure in accordance with an embodiment of the present invention. 
         FIG. 5  is a cross-sectional side view of a portion of an electronic device in which a dielectric antenna window has been formed in accordance with an embodiment of the present invention. 
         FIG. 6  is a side view of an illustrative fixture for holding electronic device structures of the type shown in  FIG. 5  during liquid adhesive curing operations in accordance with an embodiment of the present invention. 
         FIG. 7  is a cross-sectional side view of an illustrative conveyor belt system for conveying fixtures of the type shown in  FIG. 6  through an oven to cure adhesive used in mounting an antenna window structure within an electronic device in accordance with an embodiment of the present invention. 
         FIG. 8  is a cross-sectional side view of an illustrative system for holding an antenna window cap in a position that is flush with an electronic device housing during adhesive curing operations in accordance with an embodiment of the present invention. 
         FIG. 9  is a side view of a portion of an illustrative antenna window structure and associated antenna support structure showing how the antenna support structure may have adhesive overflow channels in accordance with an embodiment of the present invention. 
         FIG. 10  is a cross-sectional side view of an electronic device showing how conductive foil structures may be used to provide antenna grounding and electromagnetic interference suppression in accordance with an embodiment of the present invention. 
         FIG. 11  is a cross-sectional side view of a portion of a conductive shielding wall and an associated welded metal foil layer in accordance with an embodiment of the present invention. 
         FIG. 12  is an exploded perspective view of an illustrative electronic device having conductive structures for antenna grounding and electromagnetic shielding in accordance with an embodiment of the present invention. 
         FIG. 13  is a cross-sectional side view of a portion of the conductive structures in  FIG. 12  showing how a coupling structure such as conductive foam may be used to electrically connect shielding structures in accordance with an embodiment of the present invention. 
         FIG. 14  is a perspective view of a corner portion of an electronic device having antenna structures in accordance with an embodiment of the present invention. 
         FIG. 15  is a cross-sectional side view of the antenna structures of  FIG. 14  during assembly using support structures in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices often contain circuitry that is subject to potential electromagnetic interference effects. To suppress electromagnetic interference, it may be desirable to provide an electronic device with metal structures that serve as electromagnetic shields. The metal structures may be used to short conductive structures together. For example, metal structures may be used to provide a grounding path for an antenna. Metal structures may be interposed between circuits that handle potentially interfering signals. For example, the metal structures may be used to form a shield layer between a potential source of interference such as a display driver circuit in a display and a potential victim device such as an antenna. 
     Metal structures that may be used for shorting structures in a device together, that may be used for antenna grounding, and that may form walls and other structure that reduce electromagnetic interference may sometimes be referred to herein as shielding structures or electromagnetic interference shielding structures. Metal structures such as these may be formed from stamped sheet metal parts, from flexible metal foil, or from other conductive structures. These metal structures may be used for grounding antennas or other wireless components, may be used to prevent electromagnetic signals in one portion of a device from reaching another portion of a device, may be used to short metal structures together such as metal housing structures, or may otherwise be used in managing electrical signals in an electronic device. 
     An antenna in an electronic device may be mounted under an antenna window structure. For example, an electronic device may have a metal housing with an opening to accommodate antenna signals. The opening may be filled with a dielectric material such as plastic. The plastic may be configured to form an antenna window cap that floats within the opening. Adhesive may be used to attach the antenna cap to an internal structure such as an antenna support structure using adhesive. A fixture may be used to ensure that the antenna window cap structure and adjacent portions of the metal housing are flush before curing the adhesive. The adhesive may be a liquid adhesive having a thickness than can vary to accommodate variations in the sizes of the antenna window structures while maintaining flushness of the antenna window cap to the housing. 
     An illustrative device of the type that may include antenna window structures and electromagnetic shielding structures such as these is shown in  FIG. 1 . As shown in  FIG. 1 , electronic device  10  may include a display such as display  14 . Display  14  may be a touch screen that incorporates a layer of conductive capacitive touch sensor electrodes or other touch sensor components or may be a display that is not touch-sensitive. Display  14  may include an array of display pixels formed from liquid crystal display (LCD) components, an array of electrophoretic display pixels, an array of plasma display pixels, an array of organic light-emitting diode display pixels, an array of electrowetting display pixels, or display pixels based on other display technologies. Configurations in which display  14  includes display layers that form liquid crystal display (LCD) pixels may sometimes be described herein as an example. This is, however, merely illustrative. Display  14  may include display pixels formed using any suitable type of display technology. 
     Display  14  may be protected using a display cover layer such as a layer of transparent glass or clear plastic. 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 . 
     Device  10  may have a housing such as 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.). The periphery of housing  12  may, if desired, include walls. For example, housing  12  may have a peripheral conductive member such as a metal housing sidewall member that runs around some or all of the periphery of device  10  or may have a display bezel that surrounds display  14 . Housing  12  may have sidewalls that are curved, sidewalls that are planar, sidewalls that have a combination of curved and flat sections, sidewalls that extend upwards from an integral rear housing surface, and sidewalls of other suitable shapes. One or more openings may be formed in housing  12  to accommodate connector ports, buttons, and other components. 
     As shown in the front perspective view of  FIG. 1 , display  14  may be mounted on the front face of device  10 . As shown in the rear perspective view of  FIG. 2 , device  10  may have a rear housing member such as rear planar housing wall  18 . Wall  18  may be formed from a planar plastic structure, a planar metal structure, a glass layer, ceramics, or other materials. As an example, wall  18  and sidewalls  18 ′ may form integral portions of housing  12  and may be formed from aluminum, stainless steel, or other metals. Openings may be formed in rear wall surface  18 . For example, an opening may be formed in rear wall surface  18  of housing  12  (and, if desired, sidewalls  18 ′) to accommodate antenna window  20 . The structures for antenna window  20  may be formed from glass, ceramic, polymer (plastic) or other suitable dielectric materials. As an example, antenna window  20  may be formed from a plastic such as polycarbonate (PC), acrylonitrile butadiene styrene (ABS), or a PC/ABS blend (as examples). 
     A schematic diagram of an illustrative configuration that may be used for electronic device  10  is shown in  FIG. 3 . As shown in  FIG. 3 , electronic device  10  may include control circuitry  22  and input-output circuitry  24 . Control circuitry  22  may include storage and processing circuitry that is configured to execute software that controls the operation of device  10 . Control circuitry  22  may be implemented using one or more integrated circuits such as microprocessors, application specific integrated circuits, memory, and other storage and processing circuitry. 
     Input-output circuitry  24  may include components for receiving input from external equipment and for supplying output. For example, input-output circuitry  24  may include user interface components for providing a user of device  10  with output and for gathering input from a user. As shown in  FIG. 3 , input-output circuitry  24  may include wireless circuitry such as radio-frequency transceiver  26 . Radio-frequency transceiver  26  may include a radio-frequency receiver and/or a radio-frequency transmitter. Radio-frequency transceiver circuitry  26  may be used to handle wireless signals in communications bands such as the 2.4 GHz and 5 GHz WiFi® bands, cellular telephone bands, and other wireless communications frequencies of interest. 
     Radio-frequency transceiver circuitry  26  may be coupled to one or more antennas in antenna structures  30  using one or more transmission lines such as radio-frequency transmission line  28 . Transmission lines in device  10  may be formed from one or more segments of coaxial cable, flexible printed circuit transmission lines, microstrip transmission lines, or edge coupled transmission lines (as examples). Antenna structures  30  may include inverted-F antennas, patch antennas, loop antennas, monopoles, dipoles, or other suitable antennas. 
     Sensors  32  may include an ambient light sensor, a proximity sensor, touch sensors such as a touch sensor array for a display and/or touch buttons, pressure sensors, temperature sensors, accelerometers, gyroscopes, and other sensors. 
     Buttons  34  may include sliding switches, push buttons, menu buttons, buttons based on dome switches, keys on a keypad or keyboard, or other switch-based structures. 
     Display  14  may be a liquid crystal display, an organic light-emitting diode display, an electrophoretic display, an electrowetting display, a plasma display, or a display based on other display technologies. 
     Device  10  may also contain other components  36  (e.g., communications circuitry for wired communications, status indicator lights, vibrators, etc.). 
     Antennas may include conductive structures supported on one or more support structures. Metal housing structures such as internal or external housing structures may also be used in forming antenna structures. As an example, a metal housing in device  10  such as some or all of housing wall structures  12  may form an antenna ground structure for an antenna. Conductive materials such as metal may be supported on dielectric substrates such as injection-molded plastic carriers, glass or ceramic members, or other dielectrics. As an example, patterned metal traces for an antenna resonating element and/or parasitic antenna resonating element may be formed on printed circuit substrates. An antenna may be formed, for example, using metal traces on a printed circuit such as a rigid printed circuit board (e.g., fiberglass-filled epoxy) or a flexible printed circuit formed from a sheet of polyimide or other flexible polymer layers. Antenna structures that are formed on printed circuit substrates may be supported by support structures such as plastic support structures or other dielectric support structures. 
     Illustrative antenna structures for electronic device  10  are shown in  FIG. 4 . As shown in  FIG. 4 , antenna structures  30  may be supported using antenna support structures such as antenna support structure  38 . Antenna structures  30  may be formed from a printed circuit substrate such as printed circuit  54 . Printed circuit  54  may include patterned metal traces  46 . Antenna structures  30  may form an antenna having an antenna feed such as antenna feed  40 . Antenna feed  40  may have a positive antenna feed terminal such as feed terminal  44  and a ground antenna feed terminal such as ground feed terminal  42 . Transmission line  28  (e.g., a coaxial cable) may have a positive center conductor that is coupled to terminal  44  and an outer braid ground conductor that is coupled to terminal  42  (as an example). 
     Antenna structures  30  may be mounted on antenna support structures  38  using adhesive, screws or other fasteners and may be mounted using interposed plastic plates and other support structures. 
     Antenna support structure  38  may be formed from a dielectric such as glass, ceramic, plastic, or other dielectric materials. As an example, antenna support structure  38  may be formed from one or more injection-molded plastic members such as plastic members formed from a plastic such as polycarbonate (PC), acrylonitrile butadiene styrene (ABS), or a PC/ABS blend. 
     Plastic structure  38  may include ribs  48  that separate the interior of structure  38  into air-filled cavities such as cavities  50 . The use of air-filled cavities in structure  38  may help to lower the dielectric constant of support structure  38  and reduce antenna losses. 
     Support structure  38  may be provided with one or more openings such as openings  52 . Openings (holes)  52  may be used during assembly of an antenna window structure such as antenna window structure  20  of  FIG. 2  (as an example). 
     As shown in the cross-sectional side view of FIG.  5 , antenna window  26  of device  10  may be covered with a dielectric antenna window structure such as plastic antenna window cap structure  56  of  FIG. 5  (sometimes referred to as an antenna window cap). Antenna window cap  56  may be formed from a plastic such as polycarbonate (PC), acrylonitrile butadiene styrene (ABS), or a PC/ABS blend (as examples). 
     Antenna support structure  38  may be attached to the interior of electronic device housing  12  using adhesive  62 . Adhesive  62  may be, for example, pressure sensitive adhesive. 
     Antenna window cap  56  may be attached to antenna support structure  38  using cured liquid adhesive  58 . Initially, adhesive  58  may be dispensed in liquid form, allowing antenna cap  56  to lie flush with housing  12  while absorbing size variations in support structure  38  and housing  12 . During the curing process, the outer surface of antenna window cap  56  (i.e., the lowermost surface of antenna window cap  56  in  FIG. 5 ) and the adjacent exterior surface of housing walls  12  (i.e., the lowermost housing surface in  FIG. 5 ) may be supported by upper surface  64  of assembly tool structure  60 . Structure  60  may be, for example, a metal tray or other structure that has a flat upper surface. 
     Biasing structures such as spring loaded pins  68  on assembly tool support  66  may press housing  12  and antenna window cap  56  downwards against surface  64  in direction  70 . Holes  52  in antenna support structure  38  (see, e.g., holes  52  of  FIG. 4 ) may allow pins  68  or other biasing members to pass through antenna support structure  38  to access the upper surface of antenna window cap  56 . By simultaneously supporting antenna cap  56  and housing  12  using surface  64  while adhesive  58  is cured and thereby transformed from its uncured liquid state to a solid cured state, antenna cap  56  may be mounted flush with respect to housing  12 . 
     As shown in  FIG. 6 , assembly tool support  66  and assembly tool structure  60  may form part of a curing tray such as tray  80 . Support  66  may be mounted to spring-loaded arm  78 . A spring or other biasing mechanism may be used to bias arm  78  and structure  66  downwards in direction  70  (e.g., by rotating arm  78  about pivot axis  74  in direction  76 ). Pins  68  may press downwards on assembly  72  (e.g., device structures such as housing wall  12  and antenna window cap  56  of  FIG. 5 ) during adhesive curing. As shown in  FIG. 7 , tools such as tray  80  of  FIG. 6  may be moved through an oven such as oven  82  using a positioner such as conveyor belt  86 . As tray  80  moves through oven  82  or is otherwise exposed to heat, liquid adhesive  58  ( FIG. 5 ) may be raised to an elevated temperature (e.g., 50-85° C., 75-85° C. or other suitable temperature) for sufficiently a long time (e.g., 10-30 minutes, less than 40 minutes, more than 20 minutes, etc.) to ensure that liquid adhesive  58  is cured. Once cured, liquid adhesive  58  attaches antenna window cap  56  to support structure  38 , thereby fixing the position of antenna window cap  56  relative to device housing  12 . 
     To prevent overflow of liquid adhesive  58  when attaching antenna window cap  56  to antenna support structure  38 , antenna support structure  38  may be provided with adhesive overflow channels such as channels  88  of  FIG. 8 . Channels  88  may have the shapes of circular rings that surround holes  52  in support structures  38  or may have other shapes capable of receiving excess liquid adhesive. As shown in  FIG. 9 , excess adhesive  58  may flow upwards in direction  90  into the recess in support structure  38  that is formed by channel  88  during adhesive curing operations. Channels  88  may help prevent adhesive  58  from becoming attached to moving parts such as spring-loaded pin  68 . 
       FIG. 10  is a cross-sectional side view of device  10  showing how structures in device  10  may be provided with electromagnetic shielding. As shown in  FIG. 10 , display  14  of device  10  may have a display cover layer such as layer  92 . Layer  92  may be formed from clear glass, transparent plastic, or other suitable materials. An array of display pixels may be formed below cover layer  92 . As shown in the example of  FIG. 10 , a display pixel array may be formed from layers such as thin-film transistor layer  96  and color filter layer  94 . Layers  94  and  96  may form part of a liquid crystal display (as an example). Display driver integrated circuit  98  may be used in routing display control and data signals to thin-film transistors on thin-film transistor layer  96 . 
     Printed circuits in device  10  such as printed circuit  106  (e.g., a main logic board or other printed circuit structures formed from one or more printed circuits) may receive components  108 . Components  108  may be, for example, integrated circuits, switches, connectors, filters, discrete components, and other circuitry. 
     Wireless circuitry in device  10  such as antenna structures  30  may be sensitive to interference from components  108  and display driver circuitry  98 . To reduce interference, conductive structures such as electromagnetic signal shield wall  102  and shield layer  100  may be used in forming electromagnetic shielding. As shown in  FIG. 10 , this shielding may be used to prevent signals from display driver circuitry such as display driver integrated circuit  98  and from components  108  from reaching antenna structures  30 . Signals from antenna structures  30  or other components may also be prevented from reaching display driver circuitry  98  and other electrical components such as components  108 . 
     Shield wall  102  may be formed from a metal such as stainless steel (as an example). Shield walls such as shield wall  102  may be patterned using a stamping die, laser cutting, or other patterning techniques. Shield walls such as wall  102  may be oriented vertically as shown in  FIG. 10 . As an example, walls such as wall  102  may be supported in a vertical orientation using plastic member  110 . One or more shield walls may be oriented at right angles with respect to each other to surround a sensitive component (e.g., to shield an antenna in a corner of device  10 ). Shield walls such as wall  102  may, if desired, be attached to plastic member  110  by injection molding (insert molding) plastic member  110  over wall  102 . Plastic member  110 , which is sometimes referred to as a cover glass frame, may be attached to the inner surface of display cover layer  92  using adhesive  112 . Adhesive  112  may be, for example, a methacrylate-based liquid adhesive. Adhesive  58  for attaching antenna window cap  56  may also be a methacrylate-based liquid adhesive (as an example). 
     To form an effective electromagnetic shield, it may be desirable to use shielding wall  102  to form a vertical wall of conductor that extends between display cover layer  92  and housing  12 . As shown in  FIG. 10 , for example, shielding wall  102  may be coupled to housing  12  using spring  120 , traces on printed circuit  106 , a metal structure such as a connector on printed circuit  106  (e.g., connector  114 ), and conductive foam  116 . Housing wall  12  may be formed from anodized aluminum or other metals. To ensure formation of a satisfactory low-resistance contact between foam  116  and housing wall  12 , a portion of the anodization (aluminum oxide layer) on wall  12  may be removed by laser processing, thereby forming bare aluminum region  118 . Conductive foam  116  or other resilient electrical connection structures may form an electrical contact between region  118  and metal structure  114  on printed circuit  106 . If desired, other conductive pathways may be formed between shield wall  102  and housing wall  12 . The configuration of  FIG. 10  is merely illustrative. 
     Shield layers such as shield layer  100  of  FIG. 10  may be formed from a thin layer of conductor such as a thin flexible layer of metal (i.e., a metal foil). To minimize the amount of volume occupied within the interior of device  10 , it may be desirable to form shield layer  100  from a metal such as stainless steel that exhibits sufficient strength even at reduced thicknesses (e.g., thicknesses of less than 150 microns or even less than 20 microns). Stainless steel foil that is about 10 microns thick or other metal foils may be attached to metal structures in device  10  such as shield wall  102  using conductive adhesive, screws or other fasteners, using solder, or using welds. The use of welds may help to minimize contact resistance and thereby enhance the ability of shielding layer  100  and shielding wall  102  to form effective electromagnetic shielding within device  10 . 
     Shielding layer  100  may be formed from a sheet of stainless steel foil or other material that has a thickness of less than 150 microns, less than 100 microns, more than 70 microns, less than 70 microns, less than 40 microns, less than 20 microns, or less than 10 microns (as examples). To prevent tearing resulting from damage during welding, it may be desirable to use a sacrificial metal plate such as plate  122  of  FIG. 11  in forming welds  124 . To promote satisfactory welding, the metals used for wall  102 , foil  100 , and plate  122  may be formed from the same metal (e.g., stainless steel). Plate  122  may have a thickness that is sufficient to allow plate  122  to donate material to welds  124  during weld formation, thereby preventing layer  100  from being excessively thinned and weakened during welding. Plate  122  may, for example, have a thickness of 0.05 to 0.15 mm. 
       FIG. 12  is an exploded perspective view of device  10  in an illustrative configuration in which shielding structures are used to reduce electromagnetic interference. As shown in  FIG. 12 , device  10  may have housing portions such as housing portion  12 A and housing portion  12 B. In a completed device, housing portion  12 A may be attached to housing portion  12 B (e.g., by rotating housing  12 A in direction  128  about rotational axis  126  and by rotating housing  12 B in direction  130  around rotational axis  126 ). 
     As shown in  FIG. 12 , device  10  may have internal housing structures such as mid-plate member  131 . An edge of printed circuit board  106  may protrude from under mid-plate  131 . Springs  120  may be soldered to printed circuit board solder pads along the edge portion of printed circuit board  106 . When housings  12 A and  12 B are assembled, springs  120  may mate with contact regions  132  on shielding wall  102 . Welding locations  134  on wall  102  show where shield layer  100  (not shown in  FIG. 12 ) may be attached to shield wall  102 . 
     Shield walls  102  and  102 ′ may run perpendicular to each other and may be supported by plastic support structure  110  (e.g., by insert molding walls  102  and  102 ′ within the plastic of structure  110 ). Antenna support structure  38  may be provided with a metal structure such as jumper plate  138 . Jumper plate  138  may be formed from a sheet of stainless steel or other metal and may be attached to support structure  38  using screws that pass through plate  138  and support structure  38  and that are received by threaded portions of housing  12 A. A sheet of stainless steel or other metal layer may be used to form shielding layer  100 ′. Shielding layer  100 ′ may, for example, be formed from the same type of thin metal that is used in forming shielding layer  100 . When housings  12 A and  12 B are assembled, contact regions  140  on plate  138  may contact regions  136  on shield wall  102 ′ (e.g., using interposed conductive foam). 
       FIG. 13  is a cross-sectional side view of shielding layer  102 ′ showing how a sacrificial plate (e.g., a plate formed from a stainless steel sheet having a thickness of 0.05 to 0.15 mm) may be used in welding shield layer  102 ′ to jumper plate  138 . Conductive foam  142  may be interposed between shielding layer  102 ′ and shield wall  102 ′ to form an electrical connection between wall  102  and jumper plate  138 . Jumper plate  138 , in turn, may be electrically connected to housing  12 A via screws or other conductive structures. 
     An exploded perspective view of a portion of device  10  showing how antenna structures  30  may be mounted to support structure  38  using a support plate is shown in  FIG. 14 . As shown in  FIG. 14 , housing  12  may have alignment features such as ribs  166  and  168  that are configured to mate with corresponding alignment features on support structures  38 . When antenna support structure  38  is installed in housing  12  of device  10 , rib  170  may rest against rib  168  of housing  12  and ribs such as rib  164  of support structure  38  may rest against ribs on housing  12  such as rib  166 . 
     Support structure  38  may have alignment features such as alignment holes  160  that receive mating alignment features such as alignment posts  158  on antenna support plate  150  when antenna support plate  150  is mounted on top of antenna support structure  38 . Biasing structures such as foam structures  162  may be used to bias plate  150  and antenna structures  30  upwards in direction  172  towards display cover layer  92  ( FIG. 10 ). Antenna structures  30  (e.g., a flexible printed circuit containing antenna traces) may be mounted to an antenna support structure such as antenna support plate  150  using adhesive or other suitable attachment mechanisms. Plate  150  may help maintain antenna structures  30  in a desired shape. Due to the presence of alignment posts  158 , plate  150  may help antenna structures  30  resist lateral motion in directions  174  and  176 , thereby helping to ensure that antenna structures  30  are located where desired. 
     During assembly operations, an alignment tool such as an alignment tool with alignment pins  156  may insert pins  156  through both holes  154  on antenna structures  30  and mating holes  152  on antenna support plate  150 . This ensures that antenna structures  30  will be properly aligned with respect to antenna plate  150  along lateral dimensions  176  and  174 . Adhesive or other suitable fastening mechanism may be used to attach antenna structures  30  to antenna support plate  150 .  FIG. 15  is a cross-sectional side view showing how alignment pins  156  may be used during assembly to ensure that antenna structures  30  are aligned with respect to antenna support plate  150 . Protrusions such as antenna support plate alignment posts  158  or other alignment features may be used to ensure satisfactory alignment between antenna support plate  150  and antenna support structures  38 . Following mounting of antenna support plate  150  to antenna structures  138 , alignment members  156  may be removed. Display cover layer  92  may then be mounted on top of antenna structures  30 . 
     The foregoing is merely illustrative of the principles of this invention and various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20150611
Publication Date: 20160216
Grant Date: 20160216
Priority Date: 20120529
Inventors: SANFORD EMERY A.
LI QINGXIANG
ZHANG LIJUN
MONTEVIRGEN ANTHONY S.
DABOV TEODOR
DE JONG ERIK G.
LIN WEY-JIUN
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q1/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/526", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T29/49016", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01Q1/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/526", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T29/49016", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 49755376