PATENT DOCUMENT

Publication Number: US-8270915-B2
Application Number: US-65109407-A
Country: US
Kind Code: B2

Title: Antenna and button assembly for wireless devices

Abstract:
An antenna and button assembly is provided for a compact portable wireless device such as a wireless headset for a handheld electronic device. An antenna structure is mounted within a button structure. The button structure includes a switch actuation member that extends past the antenna structure and into engagement with a switch. The switch actuation member may reciprocate within the button structure. A user may press upon an exposed end of the switch actuation member to operate the switch. The switch may be used to control the application of power to the compact portable wireless device or to perform other suitable functions. The button structure may be formed using dielectric materials such as plastic. By forming the button structure from dielectric, clearance is provided between the antenna structure and conductive portions of the compact portable wireless device so that the antenna of the compact wireless device operates properly.

Claims:
1. A wireless headset comprising:
 an elongated metal housing portion having a longitudinal axis; 
 a microphone mounted in the metal housing portion; 
 a circuit board; 
 a switch attached to the circuit board; 
 a button guide structure that contains a guide channel; 
 a reciprocating member that is guided in the guide channel, that operates the switch, and that reciprocates along the longitudinal axis of the elongated metal housing portion; and 
 an antenna resonating element that is formed around the button guide structure so that the antenna resonating element at least partially surrounds the reciprocating member and so that the antenna resonating element at least partially surrounds the longitudinal axis. 
 
     
     
       2. The wireless headset defined in  claim 1  further comprising a dielectric housing portion that contains the button guide structure, wherein the dielectric housing portion is attached to the metal housing portion. 
     
     
       3. The wireless headset defined in  claim 1  further comprising:
 transceiver circuitry; and 
 a coaxial cable connected between the transceiver circuitry and the antenna resonating element that conveys radio-frequency signals from the transceiver circuitry to the antenna resonating element, wherein the antenna resonating element comprise a flex circuit antenna resonating element that is attached to the button guide structure, wherein the reciprocating member comprises a stem, and wherein the flex circuit surrounds the stem. 
 
     
     
       4. The wireless headset defined in  claim 1  further comprising a dielectric housing portion that contains the button guide structure. 
     
     
       5. The wireless headset defined in  claim 1  further comprising a dielectric housing portion that is attached to the metal housing portion, wherein the dielectric housing portion has portions defining grooves, wherein the circuit board has edges, and wherein the edges of the circuit board are mounted within the grooves of the dielectric housing portion. 
     
     
       6. An antenna and button assembly, comprising:
 an antenna resonating element comprising a flex circuit with a metal strip; 
 a button guide structure on which the flex circuit is mounted; 
 a switch; and 
 a reciprocating switch actuation member that reciprocates along an axis while guided by the button guide structure, wherein the reciprocating switch actuation member operates the switch, wherein the metal strip is formed around the button guide structure so that the metal strip at least partially surrounds the reciprocating switch actuation member, and wherein the flex circuit is formed around the button guide structure so that there is at least some overlap between a first end of the flex circuit and a second end of the flex circuit. 
 
     
     
       7. The antenna and button assembly defined in  claim 6  wherein the reciprocating switch actuation member comprises a stem with a rectangular cross-section, wherein the button guide structure comprises dielectric and has portions defining a hole with raised guiding structures, and wherein the raised guiding structures guide the stem as the reciprocating switch actuation member reciprocates along the axis. 
     
     
       8. The antenna and button assembly defined in  claim 6  wherein the reciprocating switch actuation member comprises:
 a stem; and 
 a button head portion attached to the stem, wherein the button head portion comprises a portion formed of a first type of plastic and a portion formed of a second type of plastic, wherein the first type of plastic is different than the second type of plastic. 
 
     
     
       9. An antenna and button assembly, comprising:
 an antenna resonating element comprising a flex circuit with a metal strip; 
 a button guide structure on which the flex circuit is mounted; 
 a switch; and 
 a reciprocating switch actuation member that reciprocates along an axis while guided by the button guide structure, wherein the reciprocating switch actuation member operates the switch, wherein the metal strip is formed around the button guide structure so that the metal strip at least partially surrounds the reciprocating switch actuation member, and wherein the flex circuit comprises at least one registration hole and wherein the button guide structure comprises at least one registration boss. 
 
     
     
       10. The antenna and button assembly defined in  claim 6  wherein the switch actuation member comprises a stem that reciprocates within the button guide structure, wherein the button guide structure comprises a plastic structure having a guide channel that guides the switch actuation member, wherein the button guide structure has an outer surface that surrounds the guide channel and the stem, and wherein the flex circuit is attached to the outer surface with adhesive. 
     
     
       11. Apparatus in a portable wireless device structure, comprising:
 a switch; 
 a switch actuation member that operates the switch when pressed by a user; 
 a guide structure that guides the switch actuation member; and 
 an antenna resonating element attached to the guide structure, wherein the guide structure comprises a plastic support structure, wherein the antenna resonating element comprises a metal strip contained within a flex circuit, wherein the flex circuit is wrapped around the plastic support structure so that the flex circuit at least partially surrounds the switch actuation member, wherein the metal strip is bent by wrapping the metal strip around the plastic support structure when the flex circuit is wrapped around the plastic support structure, and wherein the metal strip has a length and has at least one bend along its length that is in addition to any bend formed by wrapping the metal strip around the plastic support structure. 
 
     
     
       12. The apparatus defined in  claim 11  wherein the switch actuation member comprises a stem and a button head portion mounted to the stem and wherein the stem reciprocates within a guide channel portion of the guide structure. 
     
     
       13. The apparatus defined in  claim 11  wherein the flex circuit has at least one registration feature and wherein the plastic support structure has at least one boss that mates with the registration feature to align the flex circuit and the resonating element relative to the plastic support structure. 
     
     
       14. The apparatus defined in  claim 11  wherein the flex circuit has a conductive pad that is electrically connected to the metal strip, the apparatus further comprising a spring that is connected to the conductive pad and that carries a radio-frequency signal to the antenna resonating element. 
     
     
       15. Apparatus in a portable wireless device structure, comprising:
 a switch; 
 a switch actuation member that operates the switch when pressed by a user; 
 a guide structure that guides the switch actuation member; and 
 an antenna resonating element attached to the guide structure, wherein the guide structure comprises a plastic support structure, wherein the antenna resonating element comprises a metal strip contained within a flex circuit, wherein the flex circuit is wrapped around the plastic support structure so that the flex circuit at least partially surrounds the switch actuation member, wherein, when the flex circuit is unwrapped from around the plastic support structure and the switch actuation member, the flex circuit has a curved edge along its length. 
 
     
     
       16. The apparatus defined in  claim 15  wherein, when the flex circuit is unwrapped from around the plastic support structure and the switch actuation member, the metal strip has a curved edge along its length.

Description:
BACKGROUND 
     This invention relates generally to wireless communications devices, and more particularly, to antenna and button structures for wireless communications devices. 
     As integrated circuit technology advances, it is becoming feasible to construct portable wireless devices with small form factors. Examples of portable wireless devices include mobile telephones, wireless headsets, digital cameras with wireless capabilities, remote controls, wristwatch-type devices, music players with wireless functions, and handheld computers. Devices such as these are often small enough to be held in the hand and may sometimes be referred to as handheld electronic devices. Larger portable wireless devices include laptop computers. 
     Portable electronic devices sometimes use antennas to transmit and receive radio-frequency signals. For example, wireless Bluetooth headsets have antennas for communicating with cellular telephones. 
     For proper antenna operation, an antenna resonating element in a portable wireless device is generally placed at a suitable distance from the conductive structures in the device. Sometimes antennas are mounted externally. This type of arrangement is used, for example, in certain cellular telephone whip antenna arrangements. When a more compact arrangement is needed, an antenna resonating element may be mounted on a printed circuit board in a device. However, to ensure satisfactory performance, it is generally necessary to locate the resonating element on a special portion of the circuit board that has been maintained free of electrical components. If sufficient clearance is not provided for the antenna resonating element in this way, the antenna may fail to operate properly. 
     In some situations, it is not acceptable to use an external antenna design. Constraints such as a desire for compactness, light weight, and good esthetics can make external designs inappropriate. Similarly, antenna arrangements based on circuit boards in which a large clearance is provided between an antenna resonating element and components mounted on the board may be unsatisfactory because too much board real estate is dedicated to providing the clearance. 
     It would therefore be desirable to be able to provide improved compact antenna configurations for wireless communications devices. 
     SUMMARY 
     In accordance with the present invention, wireless communications devices are provided. For example, a compact portable wireless device such as a wireless headset may be provided. The compact portable wireless device may have a button. The button may be formed substantially from dielectric such as plastic. An antenna may be formed by mounting an antenna resonating element on part of the button. Because the button is formed from dielectric, the button does not interfere with the proper operation of the antenna and helps to provide suitable clearance between the antenna resonating element and conductive structures in the compact portable wireless device. 
     With one suitable arrangement, the button contains a switch such as a dome switch. The switch may be operated by pressing against the switch with a switch actuation member. The button may have a button guide structure. The button guide structure may have a guide channel. The guide channel may be provided in the form of a hole through the button guide structure. The switch actuation member may have a stem that is supported and guided by the guide channel. When pressed by a user, the switch actuation member moves along the guide channel towards the switch. Raised structures such as ribs may be used to ensure that the switch actuation member reciprocates smoothly within the guide channel. 
     The wireless device may have a metal housing portion and a dielectric housing portion. The button may be formed within the dielectric housing portion, so that the performance of the antenna is not degraded. 
     The antenna resonating element may be formed from a flex circuit containing a strip of conductor. The flex circuit may be attached to the button guide structure using adhesive. The flex circuit may contain registration holes that mate with corresponding registration bosses. One or more of the bosses may serve as heat stake bosses and may be heat treated to help secure the flex circuit to the button guide structure. 
     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 schematic diagram of an illustrative compact portable wireless device in accordance with an embodiment of the present invention. 
         FIG. 2  is a cross-sectional side view of an illustrative compact portable wireless device using an antenna and button assembly in accordance with an embodiment of the present invention. 
         FIG. 3  is an exploded perspective view of an antenna and button assembly in accordance with an embodiment of the present invention. 
         FIG. 4  is a perspective view of an antenna and button assembly in which a circuit board has been mounted to a button guide and antenna support structure in accordance with an embodiment of the present invention. 
         FIG. 5  is a top view of a portion of a printed circuit board in an antenna and button assembly in accordance with an embodiment of the present invention. 
         FIG. 6  is a cross-sectional side view of an illustrative antenna and button assembly showing how electrical contact for an antenna resonating element may be made using a spring conductor in accordance with an embodiment of the present invention. 
         FIG. 7  is a side view of an antenna and button assembly in accordance with an embodiment of the present invention. 
         FIG. 8  is a top view of an illustrative flex circuit that includes a patterned antenna resonating element in accordance with an embodiment of the present invention. 
         FIG. 9  is an end view of an illustrative antenna and button assembly showing how a flex circuit that includes an antenna resonating element may be wrapped around a button support in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention may apply to any suitable type of compact portable wireless device. Compact portable wireless devices that may be used with the antenna and button arrangements of the invention include cellular telephones, remote controls, global positioning system devices, music players, portable computers, wrist devices, pendant devices, headphone and earpiece devices, other wearable and miniature devices, and hybrid devices that include the functionality of two or more of these devices. With one particularly suitable arrangement, which is described herein as an example, the compact portable wireless device is a wireless headset. It is desirable for wireless headsets to be compact and lightweight and to be free of unsightly protrusions. 
     An illustrative wireless headset is shown in  FIG. 1 . Headset device  10  may have a elongated housing  12 . For esthetic reasons and for durability, most of housing  12  may be formed of metal or other conductive materials (as an example). Device  10  may use an antenna to communicate wirelessly with external equipment. The antenna may be enclosed in housing  12  in region  26 . To avoid interference with the antenna, the portion of housing  12  in region  26  may be constructed from plastic or other suitable dielectric. 
     The external equipment with which device  10  may communicate includes personal computers, portable computers, cellular telephones, music players, cellular telephones with music player functionality, other handheld electronic devices, and other suitable equipment. As an example, headset device  10  may be a Bluetooth® headset that communicates over a 2.4 GHz communications band with a handheld electronic device having voice communications capabilities. An illustrative Bluetooth headset arrangement of the type that may be used for device  10  is described in concurrently-filed commonly-assigned U.S. patent application No. 60/879,177, entitled “Wireless Headset,”, which is hereby incorporated by reference herein in its entirety. 
     During use of device  10 , earbud  16  is placed in a user&#39;s ear. In this position, end  28  of device  10  extends downward, towards the user&#39;s mouth. Sound (e.g., from a telephone call) may be presented to the user through slots  18  of earbud  16 . At end  28  of device  10 , device  10  has a microphone that resides within housing  12 . Opening  14  in housing  12  allows sound to be conveyed to the microphone. 
     A button such as button  30  may be located at end  26  of device  10 . Switch actuation member  20  reciprocates in directions  22  along longitudinal axis  24  of device  10  (i.e., in and out of end  26  of device  10 ). Switch actuation member  20  and other suitable portions of device  10  in the vicinity of end  26  may be formed of plastic or other suitable dielectric materials. For example, button  30  may contain a structure that guides switch actuation member  20  along axis  24 . This button guide structure may be formed of plastic or other suitable dielectric. 
     An antenna resonating element may be mounted to the button guide structure or other suitable dielectric portions of device  10  in the vicinity of button  30  and end  26 . Because the materials used to form button  30  and device  10  at end  26  are dielectrics, radio-frequency signals may be readily received by the antenna and transmitted by the antenna without interference button components. 
     A cross-sectional side view of device  10  is shown in  FIG. 2 . Microphone  54  may be mounted to a printed circuit board such as printed circuit board  52  or other suitable mounting structures. Circuit components for processing microphone signals may be mounted on board  52 . A signal path such as flex circuit cable  48  may be used to convey signals between microphone board  52  and circuit board  42 . Electrical components may be mounted to circuit board  42  (e.g., battery protection circuits, control circuits, etc.). 
     One or more light emitting diodes (LEDs) such as LED  44  may be mounted in housing  12  for use as indicators. In the illustrative arrangement of  FIG. 2 , LED  44  has been mounted on printed circuit board  42  below hole  42  in housing  12 . This allows light to escape from the housing  12  for viewing by a user. 
     Housing  12  ( FIG. 1 ) may be formed from first portion  12 - 1  and second portion  12 - 2 . First portion  12 - 1  may be formed of aluminum, stainless steel, magnesium, titanium, other suitable metals, alloys of these metals, and other suitable conductive materials. First housing portion  12 - 1  may also be formed partly or entirely from dielectric. Second portion  12 - 2  may be formed from dielectric materials such as plastic. With one suitable arrangement, no significant amounts of conductor are present at end  26  of device  10  to prevent interference with the antenna of device  10 . 
     A connector such as coaxial cable connector  40  may be mounted to printed circuit board  42 . Coaxial cable  38  may be connected to printed circuit board  34  using miniature coaxial cable connector  36 . 
     Printed circuit board  34  may contain electronic components such as radio-frequency transceiver circuits. The radio-frequency transceiver circuitry of device  10  may support wireless communications over any suitable communications bands. Examples of communications bands that device  10  may support include the Bluetooth band at 2.4 GHz, the WiFi® communications bands, the wireless USB band, etc. With one suitable arrangement, which is described herein as an example, transceiver circuitry  34  supports Bluetooth communications between device  10  and an associated handheld electronic device (e.g., a cellular telephone handset or a hybrid cellular telephone and music player device). 
     Speaker  32  may be used to generate sound for the user of device  10 . For example, when the user is using device  10  to conduct a telephone call, speaker  32  may be used to present audio from the telephone call. When device  10  is used as a music player, speaker  32  may be used to play music for the user. A source of power such as battery  50  may be used to power device  10 . 
     A switch such as switch  56  may be mounted to circuit board  42 . Switch actuation member  20  reciprocates in directions  22  along axis  24 . When a user desires to perform a function associated with button  30 , the user may press button outer surface  62 . Button outer surface  62  may be pressed to force end  58  of switch actuation member  20  against switch  56 . Depending on the type of switch being used (e.g., normally open, normally closed, etc.) pressing against switch  56  causes switch  56  to open or close. Electrical signals from switch  56  may be passed to circuitry on boards such as boards  52 ,  42 , and  34 . The control circuitry on these boards may process the switch signals and take appropriate action. Examples of actions that may be taken in device  10  when switch  56  is operated include turning device  10  on or off, resetting device  10 , changing the mode of operation of device  10 , etc. The control circuitry of device  10  may take actions based on single presses of button  30  or multiple presses of button  30 . For example, a particular action may be taken when three rapid button presses are detected within a predetermined time interval. 
     A guide structure is provided in housing portion  12 - 2 . The guide structure helps to support and guide switch actuation member  20 . Any suitable mechanical arrangement may be used to support and guide switch actuation member  20  in button  30 . With one suitable arrangement, which is described herein as an example, the guide structure includes portions that define a guide channel. Switch actuation member  20  has a stem that reciprocates along the channel. The channel may have elevated ribs or other raised portions that help to reduce friction between the sidewalls of switch actuation member  20  and the surfaces of the guide channel as the guide structure supports and guides switch actuation member  20 . 
     The antenna of device  10  has a ground (sometimes referred to as a ground plane). The ground may be formed from any suitable conductive structures in device  10 . For example, the antenna ground may be formed from conductive housing portion  12 - 1 , layers of conductor on printed circuit boards such as board  42 , combinations of such conductive structures, etc. The antenna of device  10  also has an antenna resonating element  60 . Antenna resonating element  60 , which is sometimes referred to as the antenna of device  10 , may be mounted to the guide structure or other suitable structure associated with button  30 . Because the structures that make up button  30  are primarily or entirely formed of dielectric, the antenna may function properly without interference from metal components in device  10  (e.g., circuit components on board  42 ) and without interference from the metal or other conductors that may be used in forming housing portion  12 - 1 . 
     Antenna resonating element  60  is spaced away from housing portion  12 - 1  and the electrical components of device  10  such as the components on board  42  by distance D. Distance D can be selected to ensure that the spacing between the electrical components and housing materials of device  10  and antenna resonating element  60  are sufficient for satisfactory antenna performance. The distance D may be, for example, about 3-10 mm. Larger distances D offer greater clearance between the antenna resonating element and the electrical components of device  10 , but require use of a housing portion such as portion  12 - 2  that is more elongated along axial dimension  24 . 
     Because antenna resonating element  60  is mounted within the portion of device  10  that is being used by button  30 , it is not necessary to increase the size of device  10  to accommodate antenna spacing D. No space is wasted, because antenna resonating element  60  is mounted to dielectric structures that are already being provided to support the operation of button  30 . Button  30  therefore serves at least two functions. First, button  30  uses switch  56  to provide a control mechanism for device  10 . Second, button  30 , by serving as a support structure for antenna resonating element  60 , creates clearance between antenna resonating element  60  and conductive housing portion  12 - 1  and/or other conductive structures in device  10  such as electrical components on board  42 . Because the structures of button  30  serve as both button structures and as antenna support structure, button  30  and antenna resonating element  60  are sometimes collectively referred to as a button and antenna assembly, as a button structure or assembly, as an antenna structure or assembly, as a button, as an antenna, etc. 
     An exploded perspective view of an illustrative embodiment of button  30  is shown in  FIG. 3 . As shown in the example of  FIG. 3 , button  30  may have switch actuation member  20 , button guide structure  64 , switch  56  mounted on a printed circuit board such as board  42 , and a button housing. 
     The button housing for button  30  may be formed from device housing portion  12 - 1 . This allows device  10  to retain an esthetically pleasing appearance. For example, the surfaces of button housing  12 - 1  and housing portion  12 - 1  may have similar colors and textures, so that it is not apparent to a user of device  10  that two separate housing portions are in use. Rather, to the user, it can appear as if device  10  is formed of a single unitary housing. 
     Circuit board  42  and button  30  may be attached to each other. With one suitable approach, housing portion  12 - 1  has guiding grooves  70 . During assembly of button  30 , edges  72  of circuit board  42  may slide into grooves  70 . Cyanoacrylate glue or other suitable adhesives may be used to secure circuit board edges  72  to grooves  70 . Other adhesives (e.g., ultraviolet-light cured epoxy) may be placed on printed circuit board surfaces  84 , to help secure board  42  in button  30 . 
     Button guide structure  64  has members  66  that receive surfaces  84  of board  42  and help to hold board  42  in place within button  30 . Button guide structure  64  may be formed from a non-opaque material such as clear polycarbonate. This ensures that ultraviolet light that is applied to button  30  during manufacturing can reach ultraviolet-curing adhesives that have been applied to surfaces such as surfaces  84 . 
     Button guide structure  64  may have a guide channel  68  that receives stem  86  of switch actuation member  20 . During operation, switch actuation member  20  reciprocates back and forth along longitudinal axis  24  in directions  22 . As switch actuation member  20  reciprocates, stem  86  reciprocates in channel  68 . Gussets  76  on switch actuation member  20  provide structural support for stem  86 . Button guide structure  64  may have recesses that accommodate gussets  76  when switch actuation member  20  is pressed fully inward in direction  88 . 
     Ribs may be formed along the inner surfaces of channel  68  to help provide a low-friction guide path for stem  86 . When pressed inward in direction  88 , end  58  of switch actuation member  20  may press against surface  90  of switch  56  or other suitable switch actuation surface. This closes or opens a circuit between a pair of contacts within switch  56  or otherwise operates the switch  56  so that suitable actions may be taken by the control circuitry of device  10 . 
     Switch  56  may be a side-actuated dome switch or any other suitable type of switch. In a side actuated dome switch, a rocker resides within the housing of the switch. As end  58  of switch actuation member  20  presses sideways in direction  88  against the rocker, the rocker bears against the switch housing and translates this sideways motion into vertical motion towards the surface of board  42 . A dome switch may be mounted directly beneath the rocker, so downward motion of the rocker presses against the dome switch and causes switch contacts that are associated with the dome switch to become shorted together (or opened). Control circuitry in device  10  may sense the closing (or opening) of switch  56 . 
     In addition to guiding stem  86 , button guide structure  64  may serve as a support structure for antenna resonating element  60 . Antenna resonating element  60  may be formed from a conductive strip or any other suitable antenna structure. A typical conductive strip may be about 0.6 mm in width and may have a length that is appropriate for handling the frequencies in the communications band of interest for device  10 . Conductive strips may be formed of metal or other suitable conductors and may be straight, serpentine, curved, or any other suitable shape. Illustrative metals that may be used for resonating element  60  include copper, silver, gold, and brass. If desired, other metals or alloys of these metals may be used to form antenna resonating element  90 . If the metal or other conductor that is used to form antenna resonating element  90  has a tendency to oxidize upon exposure to air, encapsulant may be used to ensure that the antenna resonating element  90  is hermetically sealed. 
     Switch actuation member  20  may have a latch portion  74 . During assembly, latch portion  74  is forced past a matching portion of button guide structure  64 . Once past the matching portion of button guide structure  64 , switch actuation member  20  and latch portion  74  snap into place. When switch actuation member  20  is withdrawn in direction  90 , surface  92  of latch  74  catches on button guide structure  64 , thereby preventing switch actuation member  20  from being removed from button  30 . 
     Switch actuation member  20  may have button head portion  78 . During operation, a user may use a finger to press against surface  62  of button portion  78 . Portion  78  may be formed from a single material or multiple materials. The illustrative arrangement of  FIG. 3  shows how button portion  78  may be formed from two different plastic portions  80  and  82  using a double shot process. Outer plastic portion  82  may be formed from clear polycarbonate to add gloss to the exposed button surface. Portion  80  may be formed from a plastic based on acrylonitrile-butadiene-styrene copolymers (sometimes referred to as ABS plastic). ABS plastic flows well during molding operations and is suitable for forming small parts. 
     Button guide structure  64  may be formed of polycarbonate (e.g., clear polycarbonate that permits ultraviolet light to reach ultraviolet-cured adhesive on surfaces  84 ). Stem  86 , which reciprocates within channel  68  of guide structure  64 , may be formed as a unitary part with portion  80 . By forming stem  86  from ABS plastic, potentially squeaky polycarbonate-to-polycarbonate surface contact between stem  86  and channel  68  of guide structure  64  is avoided. 
     Housing portion  12 - 1 , which serves as the enclosure for button  30 , may be formed from a blend of polycarbonate and ABS plastic. This type of blend provides device  10  with an attractive appearance. The ABS portion of the blend may help housing portion  12 - 1  from becoming too brittle. 
     Although shown as being formed from three separate plastic structures in  FIG. 3 , button  30  may be formed from any suitable dielectrics. Some conductive materials (e.g., portions of switch  56 ) are associated with button  30 , but these materials are insignificant when compared to the overall size and shape of the dielectric portions of button  30 . Moreover, switch  56  is located away from antenna resonating element  60  to ensure sufficient clearance around antenna resonating element  60 . 
     Antenna resonating element  60  may be formed from a strip of metal that is affixed to button guide structure  64  using adhesive or other suitable attachment mechanisms. With one particularly suitable arrangement, resonating element  60  may be formed from a strip of conductor that is part of a flex circuit. Flex circuits, which are sometimes referred to as flexible printed circuit boards, may be formed from polyimide and other flexible substrates. Copper strips or other suitable conductive strips may be pattered on the flex circuit substrate to form antenna resonating element  60 . During assembly, the flex circuit that contains antenna resonating element  60  may be mounted to button guide structure  64 . 
     If desired, the flex circuit or other suitable structure used for forming antenna resonating element  60  may be attached to an inner surface of button guide structure  64  (e.g., along the inner surface of channel  68 ). As shown in  FIG. 4 , another suitable technique involves attaching antenna resonating element  60  to outer surface  94  of button guide structure  64  by wrapping flex circuit  96  and embedded antenna resonating element  60  around button guide structure  64 . Arrangements in which flex circuit  96  is attached to an exposed outer surface of button guide structure  64  are generally considered to be easier to manufacture than arrangements in which flex circuit  96  or another antenna structure is mounted within button guide support  64 . Configurations in which antenna resonating element  60  is mounted to the exterior of button guide structure  64  are therefore described herein as an example. 
     Flex circuit  96  may contain registration features such as hole  98  and other suitable registration structures. When flex circuit  96  is wrapped around button guide structure  64 , the registration features may engage associated registration structures on button guide structure  64  such as boss  100 . This helps to ensure proper alignment of flex circuit  96  and antenna resonating element  60  relative to button guide structure  64 . Bosses such as boss  100  may serve both as registration structures and as heat stake structures that are used to attach flex circuit  96  to button guide structure. When the bosses are used as heat stake structures, heat is applied to the tips of the bosses. The heat deforms and enlarges the tips of the bosses so that the flex circuit  96  is retained. Flex circuit  96  may also be affixed to outer surface  94  using adhesive. With one suitable arrangement, flex circuit  96  is formed from adhesive-backed flex circuit material having multiple registration holes that mate with corresponding registration bosses on button guide structure  64 . At least one of the registration bosses may be heat treated to help secure flex circuit  96 . 
     A top view of a portion of circuit board  42  in the vicinity of connector  40  is shown in  FIG. 5 . As shown in  FIG. 5 , connector  40  may be connected to coaxial cable  38 . Connector  40  has positive terminals (sometimes called signal terminals)  104 , which may be connected to pad  106  via conductive path  108 . Ground terminals  102  may be connected to the ground plane of device  10  (e.g., via buried interconnects and ground plane structures in board  42 ). 
     Pad  106  may be electrically connected to antenna resonating element  60  by a spring or other suitable conductive path. A schematic cross-sectional view of button guide structure  64  that shows how spring  110  may be used to interconnect pad  106  on circuit board  42  with contact pad  112  on flex circuit  96  is shown in  FIG. 6 . Contact pad  112  may be electrically connected to antenna resonating element  60 . With one suitable arrangement, antenna resonating element  60  is formed of copper and is coated with a sealing cap formed of solder mask material. The sealing cap can help to protect the copper of the antenna resonating element  60  from oxidation. A hole may be formed in the sealing cap to allow a gold plating to be formed for pad  112 . Clip  110  may press against pad  112 , as shown schematically in  FIG. 6 . If desired, clip  110  can be wrapped tightly around the exterior of button guide structure  64  to help hold flex circuit  96  in place against button guide structure  64 . A heat stake boss may be used to help secure clip  110  to button guide structure  64 . 
     A side view of button  30  after circuit board  42  has been attached to button guide structure  64  is shown in  FIG. 7 . As shown in  FIG. 7 , even though button guide structure  64  has a slanted shape (in this example), antenna resonating element  60  is able to conform to the shape of button guide structure  64  when flex circuit  96  is wrapped around button guide structure.  FIG. 8  shows a suitable shape that may be used for flex circuit  96  when it is desired to wrap flex circuit  96  around a slanted button guide structure of the type shown in  FIG. 7 . In the illustrative arrangement of  FIG. 8 , flex circuit  96  has registration holes  98  that may mate with corresponding bosses on button guide structure  64 . Notch  114  may be used to accommodate spring  110  of  FIG. 6 . 
     An end view of button  30  is shown in  FIG. 9 . As shown in  FIG. 9 , flex circuit  96  may be wrapped around button support structure  64  so that there is an overlap region  118 . If desired, the length of flex circuit  96  may be adjusted so that there is no overlap or so that there is more or less overlap than shown in  FIG. 9 . Open portions  120  of guide structure  64  may be used to accommodate gussets  76  ( FIG. 3 ) when switch actuation member  20  is moved in direction  88  towards switch  56  along axis  24 . 
     Boss  100  may be a heat stake boss that has a rectangular cross-section so that boss  100  fits into rectangular hole  98  of  FIG. 8 . Spring  110  may have a rectangular hole that makes with the rectangular cross-section of boss  100 . Boss  100  may be used to help secure clip  110  and flex circuit  96  to button guide structure  64 . 
     Guide channel  68  of button guide support structure  64  may have guiding ribs such as ribs  116 . Ribs  116  support and guide stem  86  of switch actuation member  20  as switch actuation member  20  and stem  86  reciprocate along axis  24 . The use of four guiding ribs is merely illustrative. Any suitable number of ribs or other raised guiding structures may be used on the inner surfaces of channel  68  if desired. Moreover, ribs  116  may be provided on stem  86  in addition to or instead of ribs  116  on button guide structure  64 . 
     If desired, buttons of other suitable shapes and sizes may be used. For example, switch actuation member  20  and corresponding guide channel  68  in button guide structure  64  may have circular cross sections, oval cross sections, square cross sections, triangular cross sections, etc. Switch actuation member head portion  70  may be slanted (as shown in the side view of  FIG. 7 ) or may be oriented perpendicularly. Button guide structure  64 , housing portion  12 - 2 , and switch actuation member  20  may be provided using a different number of parts. For example, parts may be merged (e.g., by combining housing portion  12 - 2  and button guide structure), parts may be divided (e.g., by forming two or more parts in place of housing portion  12 - 2 ), etc. The button and antenna structures described in connection with  FIGS. 1-9  are merely illustrative. 
     When a flex circuit is used, the strip of conductive material that makes up the antenna resonating element can be formed around the button guide structure by wrapping the flex circuit around the button guide structure and by securing the flex circuit and antenna strip using heat stakes, adhesive, or other suitable attachment mechanisms. If desired, alternative arrangements for forming the antenna on the button guide structure may be used. 
     For example, the button guide structure and antenna resonating element may be constructed using a double shot molding followed by a metal plating step. With this type of arrangement, the first shot of the double shot molding may form the majority of the button guide support structure  64 . The second shot may create a recessed groove in the shape of antenna resonating element  60  (e.g., a strip antenna shape) on the surface of the button support structure. The main portion of the button support structure and the portion of the button support structure that creates the recessed groove may be formed from one or more polymers (e.g., polycarbonate, ABS plastic, combinations of polycarbonate and ABS plastic, etc.) or other suitable dielectric. With one suitable arrangement, polymers may be selected so that metal from the metal plating step will adhere only to the recessed groove, while the rest of the button support structure remains unplated. Following fabrication, the button support structure and its integrated metal-plated antenna resonating element have the appearance of structure  64  of  FIG. 3 . 
     As another example, antenna resonating element  60  may be formed by stamping antenna resonating element  60  from a conductive material such as a metal. Suitable metals that may be used include brass and copper (as examples). The stamped metal antenna resonating element may be formed around the button guide support structure  64  by insert molding the resonating element into a suitable dielectric (e.g., a polymer). The stamped metal antenna resonating element may also be formed around the button guide support structure by attaching the stamped antenna resonating element to button guide support structure  64  using adhesive, heat stakes, adhesive and heat stakes, or other suitable attachment mechanisms. 
     If desired, antenna resonating element  60  may be formed around button guide support structure  64  using vapor deposition or by printing a conductive ink or other coating onto button guide support structure. 
     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.

Metadata:
Filing Date: 20070106
Publication Date: 20120918
Grant Date: 20120918
Priority Date: 20070106
Inventors: SANFORD EMERY A.
ZHANG ZHIJUN
HANKEY EVANS
Assignee: APPLE INC
CPC Classifications: [{"code": "H04R1/1041", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/44", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/44", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 39310332