PATENT DOCUMENT

Publication Number: US-9876273-B2
Application Number: US-201514844911-A
Country: US
Kind Code: B2

Title: Electronic device having antenna on grounded speaker box

Abstract:
An electronic device may be provided with a housing in which electrical components are mounted. The housing may include a metal portion that serves as ground. An antenna for the electronic device may be formed from metal traces on an antenna support such as a flexible printed circuit. The flexible printed circuit may be mounted to a speaker box. The speaker box may have one or more walls formed from metal plates. A metal plate in a speaker box may be coupled to a metal clip. The metal clip may be shorted to a metal stiffener that overlaps a tail portion of the flexible printed circuit. The metal stiffener may have an opening that is aligned with an opening in the metal clip. A metal fastener such as a screw may pass through the openings to short the metal clip, stiffener, and metal plate to ground.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 a conductive housing structure; 
 a speaker box having a wall that includes at least one metal structure; 
 grounding path structures that ground the metal structure to the conductive housing structure; and 
 an antenna supported by the speaker box, wherein the grounding path structures have an opening, are shorted to the metal structure, and comprise a metal fastener that passes through the opening. 
 
     
     
       2. The electronic device defined in  claim 1  wherein the metal structure comprises a metal plate and wherein the speaker box comprises plastic molded over at least part of the metal plate. 
     
     
       3. The electronic device defined in  claim 2  wherein the grounding path structures include a metal clip that is shorted to the metal plate. 
     
     
       4. The electronic device defined in  claim 3  wherein the opening is formed in the metal clip. 
     
     
       5. The electronic device defined in  claim 4  wherein the conductive housing structure comprises a metal housing wall and wherein the metal housing wall has an opening that receives the metal fastener. 
     
     
       6. The electronic device defined in  claim 1  wherein the antenna comprises a flexible printed circuit that has metal antenna resonating element traces and that is attached to a surface of the speaker box. 
     
     
       7. An electronic device, comprising:
 a conductive housing structure; 
 a speaker box having a wall that includes at least one metal structure; 
 grounding path structures that ground the metal structure to the conductive housing structure; and 
 an antenna supported by the speaker box, wherein the grounding path structures include a metal clip and wherein the speaker box includes a first plastic portion in which the metal structure is embedded and includes a second plastic portion in which the metal clip is embedded. 
 
     
     
       8. The electronic device defined in  claim 7  wherein the metal plate and the metal clip are welded together after the first and second portions of the speaker box are joined together to form the speaker box. 
     
     
       9. An electronic device, comprising:
 a conductive housing structure; 
 a speaker box having a wall that includes at least one metal structure; 
 grounding path structures that ground the metal structure to the conductive housing structure; 
 an antenna supported by the speaker box, wherein the antenna comprises a flexible printed circuit that has metal antenna resonating element traces and wherein the flexible printed circuit has a tail portion; and 
 a stiffener that overlaps the tail portion. 
 
     
     
       10. The electronic device defined in  claim 9  further comprising a coaxial cable that is coupled to pads on the flexible printed circuit tail portion, wherein the stiffener comprises a metal stiffener and has an opening, and wherein the grounding path structures include the metal stiffener and a metal screw that is shorted between the metal stiffener and the conductive housing structures. 
     
     
       11. The electronic device defined in  claim 10  wherein the speaker box comprises plastic and comprises a metal clip that is embedded in the plastic and that is shorted to the metal stiffener, wherein the metal clip forms a portion of the grounding path structures and is shorted to the metal structure. 
     
     
       12. The electronic device defined in  claim 11  wherein the metal clip has a hole through which the metal screw passes and wherein the metal structure comprises a metal plate that forms a wall in the speaker box. 
     
     
       13. Apparatus, comprising:
 an antenna support structure; 
 metal traces on the antenna support structure that form an antenna; 
 a metal stiffener that overlaps a portion of the antenna support structure; 
 a ground structure; and 
 a grounding path structure that shorts the metal stiffener to the ground structure, wherein the grounding path structure comprises a conductive fastener that fastens the antenna support structure to the ground structure. 
 
     
     
       14. The apparatus defined in  claim 13  wherein the ground structure comprises a metal electronic device housing wall. 
     
     
       15. The apparatus defined in  claim 14  wherein the antenna support structure comprises a flexible printed circuit. 
     
     
       16. The apparatus defined in  claim 14  further comprising a coaxial cable that is coupled to the portion of the antenna support structure that is overlapped by the metal stiffener, wherein the grounding path structure further comprises a metal clip that is shorted to the metal stiffener. 
     
     
       17. The apparatus defined in  claim 16  further comprising a speaker box having plastic structures that are molded over at least part of the metal clip. 
     
     
       18. The apparatus defined in  claim 17  further comprising a metal plate that forms a wall for the speaker box, wherein the plastic structures are molded over at least part of the metal plate. 
     
     
       19. An electronic device, comprising:
 a metal structure that serves as ground; 
 a speaker box having plastic portions and at least one metal plate; 
 a flexible printed circuit having metal traces that form an antenna, wherein the flexible printed circuit is supported by the speaker box; and 
 a coaxial cable coupled to a tail portion of the flexible printed circuit; and 
 a metal stiffener that overlaps the tail portion, wherein the metal stiffener is coupled to the metal plate and is shorted to the metal structure that serves as ground. 
 
     
     
       20. The electronic device defined in  claim 19  wherein the metal structure comprises a metal electronic device housing, the electronic device further comprising:
 a metal fastener; and 
 a metal member in the plastic portions of the speaker box, wherein the metal member is electrically coupled to the metal plate and to the metal stiffener and wherein the metal fastener grounds the metal plate, metal member, and metal stiffener to the metal electronic device housing.

Description:
BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with wireless communications circuitry. 
     Electronic devices often include wireless circuitry with antennas. For example, cellular telephones, computers, and other devices often contain antennas for supporting wireless communications. 
     It can be challenging to form electronic device antenna structures with desired attributes. In some wireless devices, the presence of conductive structures such as conductive housing structures and conductive components can influence antenna performance. Antenna performance may not be satisfactory if the housing structures are not configured properly and interfere with antenna operation or if antennas are undesirably influenced due to conductive structures in nearby components. Device size can also affect performance. It can be difficult to achieve desired performance levels in a compact device, particularly when the compact device has conductive components and housing structures. 
     It would therefore be desirable to be able to provide improved wireless circuitry for electronic devices such as electronic devices that include conductive structures. 
     SUMMARY 
     An electronic device may be provided with a housing in which electrical components are mounted. The housing may include a metal portion that serves as ground. 
     An antenna for the electronic device may be formed from metal traces on an antenna support such as a flexible printed circuit. The flexible printed circuit may be mounted to a speaker box under an inactive edge portion of a display. 
     The speaker box may have one or more walls formed from metal plates. The metal plates may have portions that are secured within molded plastic speaker box wall structures. 
     A metal plate in a speaker box may be coupled to a metal clip. The metal plate may be formed in a first speaker box portion and the metal clip may be formed in a second speaker box portion. The metal clip and metal plate may be welded to each other after joining the first and second speaker box portions. 
     The metal clip may be shorted to a metal stiffener that overlaps a tail portion of the flexible printed circuit. The metal stiffener may serve as a mechanical support for the flexible printed circuit and may form part of a signal path that helps ground the metal plate. A coaxial cable may be soldered or otherwise mounted to contact pads on the flexible printed circuit tail portion. 
     The metal stiffener may have an opening that is aligned with an opening in the metal clip. A metal fastener such as a screw may pass through the openings to short the metal clip, stiffener, and metal plate to ground. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device in accordance with an embodiment. 
         FIG. 2  is a schematic diagram of illustrative circuitry in an electronic device in accordance with an embodiment. 
         FIG. 3  is perspective view of an illustrative speaker box being used to support an antenna in accordance with an embodiment. 
         FIG. 4  is a cross-sectional side view of an illustrative speaker box showing how portions of the walls of the speaker box may be formed from metal plates in accordance with an embodiment. 
         FIG. 5  is a perspective view of an illustrative flexible printed circuit having antenna traces that form an antenna and having a metal grounded stiffener in accordance with an embodiment. 
         FIG. 6  is a view of an end portion of a coaxial cable that has been coupled to antenna terminals on a portion of the flexible printed circuit of  FIG. 5  that is overlapped and supported by the stiffener in accordance with an embodiment. 
         FIG. 7  is a perspective view of the underside of the flexible printed circuit and stiffener of  FIGS. 5 and 6  in accordance with an embodiment. 
         FIG. 8  is a perspective view of an illustrative metal top plate for a speaker box and an associated metal grounding clip in accordance with an embodiment. 
         FIG. 9  is an exploded perspective view of an illustrative speaker box having mating upper and lower portions in accordance with an embodiment. 
         FIG. 10  is a perspective view of an illustrative speaker box that is being used to support an antenna on a flexible printed circuit in accordance with an embodiment. 
         FIG. 11  is a cross-sectional side view of the speaker box of  FIG. 10  in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices such as electronic device  10  of  FIG. 1  may be provided with wireless communications circuitry. The wireless communications circuitry may be used to support wireless communications in multiple wireless communications bands. 
     The wireless communications circuitry may include one more antennas. The antennas of the wireless communications circuitry can include loop antennas, inverted-F antennas, strip antennas, planar inverted-F antennas, slot antennas, hybrid antennas that include antenna structures of more than one type, or other suitable antennas. 
     Electronic device  10  may be a portable electronic device or other suitable electronic device. For example, electronic device  10  may be a laptop computer, a tablet computer, a somewhat smaller device such as a wrist-watch device, pendant device, headphone device, earpiece device, or other wearable or miniature device, a handheld device such as a cellular telephone, a media player, or other small portable device. Device  10  may also be a set-top box, a desktop computer, a display into which a computer or other processing circuitry has been integrated, a display without an integrated computer, or other suitable electronic equipment. 
     Device  10  may include a housing such as housing  12 . Housing  12 , which may sometimes be referred to as a case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of these materials. In some situations, parts of housing  12  may be formed from dielectric or other low-conductivity material. In other situations, housing  12  or at least some of the structures that make up housing  12  may be formed from metal elements. 
     Device  10  may, if desired, have a display such as display  14 . Display  14  may be mounted on the front face of device  10 . Display  14  may be a touch screen that incorporates capacitive touch electrodes or may be insensitive to touch. The rear face of housing  12  (i.e., the face of device  10  opposing the front face of device  10 ) may have a planar housing wall. 
     Display  14  may include pixels formed from light-emitting diodes (LEDs), organic LEDs (OLEDs), plasma cells, electrowetting pixels, electrophoretic pixels, liquid crystal display (LCD) components, or other suitable pixel structures. A display cover layer such as a layer of clear glass or plastic may cover the surface of display  14  or the outermost layer of display  14  may be formed from a color filter layer, thin-film transistor layer, or other display layer. Buttons such as button  24  may pass through openings in the cover layer. The cover layer may also have other openings such as an opening for speaker port  26 . Housing  12  may have openings such as openings for audio jack port  50 , connector port  52 , and speaker port  54 . 
     Housing  12  may include peripheral housing structures such as structures  16 . Structures  16  may run around the periphery of device  10  and display  14 . In configurations in which device  10  and display  14  have a rectangular shape with four edges, structures  16  may be implemented using peripheral housing structures that have a rectangular ring shape with four corresponding edges (as an example). Peripheral structures  16  or part of peripheral structures  16  may serve as a bezel for display  14  (e.g., a cosmetic trim that surrounds all four sides of display  14  and/or that helps hold display  14  to device  10 ). Peripheral structures  16  may also, if desired, form sidewall structures for device  10  (e.g., by forming a metal band with vertical sidewalls, curved sidewalls, etc.). Peripheral housing structures  16  may be formed from metal such as stainless steel, aluminum, or other suitable materials and may form antenna ground structures, portions of antenna resonating elements (e.g., inverted-F antennas and other antennas for cellular telephone communications, etc.). Other conductive housing structures (e.g., a planar rear wall for device housing  12 ) may also be formed from metal such as stainless steel, aluminum, or other suitable materials and may form ground structures (e.g., antenna ground). 
     Display  14  may have an array of pixels that form an active area that displays images for a user of device  10 . An inactive border region may run along one or more of the peripheral edges of the active area. Display  14  may include conductive structures such as an array of capacitive electrodes for a touch sensor, conductive lines for addressing pixels, driver circuits, etc. Housing  12  may include internal conductive structures such as metal frame members and a planar conductive housing member (sometimes referred to as a midplate) that spans the walls of housing  12  (i.e., a substantially rectangular sheet formed from one or more parts that is welded or otherwise connected between opposing sides of member  16 ). Device  10  may also include conductive structures such as printed circuit boards, components mounted on printed circuit boards, and other internal conductive structures. These conductive structures, which may be used in forming a ground in device  10 , may be located in the center of housing  12  and may extend under the central active area of display  14 . 
     In inactive display regions  22  and  20 , openings may be formed within the conductive structures of device  10  (e.g., between peripheral conductive housing structures  16  and opposing conductive ground structures such as conductive housing midplate or rear housing wall structures, a printed circuit board, and conductive electrical components in display  14  and device  10 ). These openings may be filled with air, plastic, and other dielectrics and may be used in forming antenna resonating elements for one or more antennas in device  10 . 
     If desired, antenna traces on a flexible printed circuit or other carrier may be used to form antenna resonating elements (e.g., resonating elements for a monopole antenna, inverted-F antenna, etc.). A flexible printed circuit may have a flexible substrate formed from a layer of polyimide or other flexible sheet(s) of polymer. The flexible printed circuit on which the antenna resonating element has been formed may be mounted in a location in device  10  that allows the antenna to transmit and receive wireless signals. With one suitable arrangement, one or more wireless local area network antennas may be formed from flexible printed circuit(s) mounted under one or more portions of the display cover layer for display  14  in inactive areas of display  14  such as areas  20  and/or  22 . During operation, these antennas may transmit and receive antenna signals that have passed through dielectric portions of device  10  such as the overlapping portions of the display cover layer. If desired, housing  12  may be formed from dielectric and/or may be formed from metal with dielectric antenna windows located over the antennas to permit antenna signals to be transmitted and received by the antennas through the housing. 
     In general, device  10  may include any suitable number of antennas (e.g., one or more, two or more, three or more, four or more, etc.). The antennas in device  10  may be located at opposing first and second ends of an elongated device housing (e.g., at ends  20  and  22  of device  10  of  FIG. 1 ), along one or more edges of a device housing, in the center of a device housing, in other suitable locations, or in one or more of these locations. 
     In a typical scenario, device  10  may have one or more upper and one or more lower antennas (as an example). An upper antenna may, for example, be formed at the upper end of device  10  in region  22 . A lower antenna may, for example, be formed at the lower end of device  10  in region  20 . The antennas may be used separately to cover identical communications bands, overlapping communications bands, or separate communications bands. The antennas may be used to implement an antenna diversity scheme or a multiple-input-multiple-output (MIMO) antenna scheme (e.g., a wireless local area network MIMO scheme). 
     Antennas in device  10  may be used to support any communications bands of interest. For example, device  10  may include antenna structures for supporting local area network communications, voice and data cellular telephone communications, global positioning system (GPS) communications or other satellite navigation system communications, Bluetooth® communications, etc. 
     A schematic diagram of device  10  is shown in  FIG. 2 . As shown in  FIG. 2 , transceiver circuitry  90  in wireless circuitry  34  may be coupled to antenna structures such as antenna  40  using paths such as path  92 . Wireless circuitry  34  may be coupled to control circuitry  28 . Control circuitry  28  may be storage and processing circuitry that includes 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 circuitry  28  may be used to control the operation of device  10 . This processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, application specific integrated circuits, etc. 
     Control circuitry  28  may be used to run software on device  10 , such as internet browsing applications, voice-over-internet-protocol (VOIP) telephone call applications, email applications, media playback applications, operating system functions, etc. To support interactions with external equipment, circuitry  28  may be used in implementing communications protocols. Communications protocols that may be implemented using storage and processing circuitry  28  include internet protocols, wireless local area network protocols (e.g., IEEE 802.11 protocols—sometimes referred to as WiFi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol, cellular telephone protocols, multiple-input and multiple-output (MIMO) protocols, antenna diversity protocols, etc. 
     Control circuitry  28  may be coupled to input-output devices  32 . Input-output devices  32  may be used to allow data to be supplied to device  10  and to allow data to be provided from device  10  to external devices. Input-output devices  32  may include user interface devices, data port devices, and other input-output components. For example, input-output devices  32  may include touch screens, displays without touch sensor capabilities, buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones, cameras, buttons, speakers, status indicators, light sources, audio jacks and other audio port components, digital data port devices, light sensors, position and orientation sensors (e.g., sensors such as accelerometers, gyroscopes, and compasses), capacitance sensors, proximity sensors (e.g., capacitive proximity sensors, light-based proximity sensors, etc.), fingerprint sensors (e.g., a fingerprint sensor integrated with a button such as button  24  of  FIG. 1  or a fingerprint sensor that takes the place of button  24 ), etc. 
     To provide antenna structures such as antenna(s)  40  with the ability to cover communications frequencies of interest, antenna(s)  40  may be provided with circuitry such as filter circuitry (e.g., one or more passive filters and/or one or more tunable filter circuits). Discrete components such as capacitors, inductors, and resistors may be incorporated into the filter circuitry. Capacitive structures, inductive structures, and resistive structures may also be formed from patterned metal structures (e.g., part of an antenna). If desired, antenna(s)  40  may be provided with adjustable circuits to tune antennas over communications bands of interest. 
     Path  92  may include one or more transmission lines. As an example, signal path  92  of  FIG. 2  may be a transmission line having a positive signal conductor such as line  94  and a ground signal conductor such as line  96 . Lines  94  and  96  may form parts of a coaxial cable or a microstrip transmission line (as examples). A matching network formed from components such as inductors, resistors, and capacitors may be used in matching the impedance of antenna(s)  40  to the impedance of transmission line  92 . Matching network components may be provided as discrete components (e.g., surface mount technology components) or may be formed from housing structures, printed circuit board structures, traces on plastic supports, etc. Components such as these may also be used in forming filter circuitry in antenna(s)  40  and may be tunable and/or fixed components. 
     Transmission line  92  may be coupled to antenna feed structures associated with antenna  40 . As an example, antenna  40  may be formed from an antenna resonating element trace on a flexible printed circuit (see, e.g., trace  104  of  FIG. 2 ). The antenna resonating element trace and an antenna ground (e.g., a ground formed from a portion of housing  12 , ground traces in one or more printed circuits, etc.) may be used to form an inverted-F antenna, a slot antenna, a hybrid inverted-F slot antenna or other antenna having an antenna feed with a positive antenna feed terminal such as terminal  98  and a ground antenna feed terminal such as ground antenna feed terminal  100 . Positive transmission line conductor  94  may be coupled to positive antenna feed terminal  98  and ground transmission line conductor  96  may be coupled to ground antenna feed terminal  100 . Other types of antenna feed arrangements may be used if desired. For example, antenna structures  40  may be fed using multiple feeds. The illustrative feeding configuration of  FIG. 2  is merely illustrative. 
     A speaker such as speaker  106  of  FIG. 3  may have an opening such as opening  108  that is aligned with speaker port  54  of  FIG. 1 . Speaker  106  may have a speaker driver such as driver  114  that is located in interior cavity (speaker volume)  116  of speaker box  118 . Speaker box  118 , which may sometimes be referred to as a speaker enclosure, may have a wall such as upper wall  110 . An antenna support structure such as flexible printed circuit  112  may contain antenna traces for forming antenna  40  and may be mounted on upper wall  110  using adhesive or other suitable attachment mechanisms. Speaker  106  and, in particular, antenna  40  on speaker box  118 , may be installed under an inactive portion of display  14  (e.g., under a display cover layer region that serves as an antenna window). 
     Opening  108  in speaker box  118  may allow sound to pass from interior region  116  to the exterior of device  10  via speaker port  54  (e.g., through one or more openings in housing  12 ). At the same time, speaker box  118  may serve as a support that holds flexible printed circuit  112  of antenna  40  at a desired distance in dimension Z from underlying ground structures (e.g., metal housing structures under box  118 , ground lines in printed circuits that are overlapped by box  118 , etc.). Speaker box  118  may have any suitable hollow shape (e.g., a spherical shape, a rectangular box shape, a shape with curved and/or flat portions, etc.). The use of a rectangular box shape for speaker box  118  of  FIG. 3  is merely illustrative. 
     The walls of speaker box  118  may be formed from materials such as plastic and/or metal. Metal walls (e.g., walls of stainless steel, etc.) may be relatively thin for a given strength, and may therefore be used to help reduce the overall thickness of box  118 . The use of metal plates to form one or more of the walls of box  18  therefore allows the volume of interior cavity  116  to be increased without increasing the exterior dimensions of box  118 . 
     A cross-sectional side view of speaker box  118  of speaker  106  in an illustrative configuration in which box  118  has an upper metal plate and opposing lower metal plate is shown in  FIG. 4 . As shown in  FIG. 4 , metal plate  120  may form part or all of an upper wall for speaker box  118  and metal plate  122  may form part or all of a lower wall for speaker box  118 , and plastic sidewall structures  128  may be formed from plastic that is injection molded over the outer edges of metal plates  120  and  122 . Metal plates  120  and  122  have the potential to influence antenna operation for antenna  40 . To enhance antenna performance, ground paths such as paths  124  may be used to short (ground) plates  120  and  122  to ground  126 . Ground  126  may be associated with ground traces in a printed circuit that runs under box  118 , metal in housing  12 , or other ground structures. Paths  124  may be formed from ground path structures such as metal wires, traces in flexible printed circuits, metal clips (e.g., metal structures embedded in plastic portions of box  118  and/or coupled to metal plates  120  and/or  122 ), metal stiffener structures, or other conductive structures. 
     A perspective view of flexible printed circuit  112  is shown in  FIG. 5 . Flexible printed circuit  112  may contain a patterned metal layer (e.g., a copper layer) and one or more dielectric layers (e.g., a layer of polyimide substrate, a coverlay layer that covers the metal layer, vias for routing signals to contact pads, etc.). The metal traces in printed circuit  112  may be patterned to form antenna resonating element  104  of antenna  40  ( FIG. 2 ). In the example of  FIG. 5 , flexible printed circuit  112  has a tail portion such as tail  112 ′ that extends downwards from the top surface of box  118  (not shown in  FIG. 5 ). Tail  112 ′ is overlapped and stiffened using stiffener  130 . Stiffener  130  may be formed from a sheet of metal (e.g., a planar stamped stainless steel member or other planar metal member, etc.). Stiffener  130  may have openings such as screw holes  132  and  134 . Metal fasteners such as screws may pass through holes  132  and  134  and may be received within threaded openings in housing  12 , metal brackets and other support structures, port connectors, and other structures in device  10 . The metal screws may help form grounding paths such as paths  124  of  FIG. 4 . 
     Stiffener  130  may help structurally support flexible printed circuit tail  112 ′ and thereby facilitate attachment of coaxial cable  92  to the underside of tail  112 ′.  FIG. 6  shows how coaxial cable  92  may have a ground conductor (conductor  96 ) that is coupled to ground pad  100 ′ of tail portion  112 ′ of flexible printed circuit  112  at antenna ground feed  100  and may have a positive signal line conductor (conductor  94 ) that is coupled to positive signal pad  98 ′ of portion  112 ′ at positive antenna feed  98 , thereby forming a feed for antenna  40 . A perspective view of the underside of flexible printed circuit  112  showing how stiffener  130  may overlap tail portion  112 ′ and the end of coaxial cable  92  is shown in  FIG. 7 . A layer of adhesive  142  may be formed under flexible printed circuit  112  in region  140  to help attach flexible printed circuit  112  to the surface of upper wall  110  of speaker box  118 . 
       FIG. 8  is a perspective view of an illustrative upper metal plate for speaker box  118 . As shown in  FIG. 8 , a metal structure such as clip  150  or other metal member may have a vertically extending portion such as portion  152  that is joined to portion  120 ′ along seam  154 . Laser welds, solder, conductive adhesive, and/or other conductive fastening techniques may be used to electrically couple upper metal plate  120  to clip  150  at seam  154 . This allows clip  150  to serve as part of a grounding path such as grounding path  124  of  FIG. 4 . 
     Clip  150  may have openings such as opening  160  to receive screws (e.g., to help mechanically and/or electrically couple clip  150  to housing  12  and/or other ground structures). The opening may pass through upper clip portion  156  and parallel lower clip portion  158 . 
       FIG. 9  shows how speaker box  118  may be formed from multiple joined parts. As shown in the illustrative exploded perspective view of  FIG. 9 , speaker box  118  has an upper portion such as speaker box portion  118 - 1  and a mating lower portion such as speaker box portion  118 - 2 . Upper portion  118 - 1  may have metal plate  120  embedded in injection molded plastic  128 . Lower portion  118 - 2  may have metal plate  122  and metal clip  150  embedded in injection molded plastic  128 . Speaker box  118  may be formed by moving portion  118 - 1  towards portion  118 - 2  to join portions  118 - 1  and  118 - 2  together. Ultrasonic welds, adhesive, fasteners, or other attachment mechanisms may be used in joining portions  118 - 1  and  118 - 2 . 
     When portions  118 - 1  and  118 - 2  are joined, portion  152  of clip  150  will meet portion  120 ′ of plate  120  along seam (joint)  154 . Laser welds, solder, and/or conductive adhesive may be used in coupling clip  150  and plate  120  along seam  154  after portions  118 - 1  and  118 - 2  have been assembled. 
     With this approach, clip  150  is joined to plate  120  after upper and lower mating portions of speaker box  118  have been assembled. By delaying the process of joining clip  150  and plate  120  until after speaker box assembly, residual stresses that might otherwise be imparted to speaker box  118  from clip  140  and plate  120  may be minimized. This helps box  118  to maintain desired acoustic properties such as desired acoustic sealing levels. 
     A perspective view of speaker  106  is shown in  FIG. 10 . As shown in  FIG. 10 , a portion of upper surface  110  of speaker box  118  may be formed from metal plate  120  in molded plastic wall portions  128 . Stiffener  130  may overlap tail portion  112 ′ of flexible printed circuit  112  for antenna  40 , thereby providing both structural support for tail portion  112 ′ and grounding for the conductive structures of speaker box  118 . Opening  108  may be formed in a plastic end wall of plastic  128  or from other portions of speaker box  118 . 
       FIG. 11  is a cross-sectional side view of speaker  106  of  FIG. 10  taken along line  170  and viewed in direction  172 . As shown in  FIG. 11 , screw  174  may be received within threaded opening  176  in housing  12 , which may serve as ground  126 . Screw  174  may pass through an opening in flexible printed circuit  178  (e.g., a flexible printed circuit coupled to a port connector for port  52  and/or other grounded structures). Screw  174  may also pass through opening  132  in stiffener  130 , openings such as opening  160  in portions  156  and  158  of clip  150 , and an aligned opening in plastic  128  of box  118 . Ground  126  may be formed from ground structures in device  10  such as layer  178  (e.g., one or more flexible printed circuit layers such as a flexible printed circuit used for mounting a data port connector within device  10 ), and/or housing  12 . The metal grounding path structures of clip  150 , stiffener  130 , and screw  174  form a grounding path to ground  126 . By grounding metal plate  120  (and, if desired metal plate  122 ) in this way, electromagnetic noise can be suppressed and antenna performance for antenna  40  can be improved. 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20150903
Publication Date: 20180123
Grant Date: 20180123
Priority Date: 20150903
Inventors: Lui Timothy S.
MEYER ROBERT F.
Hristov Stoyan P.
FLETCHER ASHLEY E.
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q9/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/44", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/242", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/241", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/241", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/44", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/242", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 58189514