US008270915B2
`
`US 8,270,915 B2
`(10) Patent No.:
`a2) United States Patent
`Sanford et al.
`(45) Date of Patent:
`Sep. 18, 2012
`
`
`(75)
`
`(54) ANTENNA AND BUTTON ASSEMBLY FOR
`WIRELESS DEVICES
`Inventors: Emery A. Sanford, San Francisco, CA
`(US); Zhijun Zhang, Santa Clara, CA
`:
`H
`Oe wns Hankey, San Francisco,
`(US)
`
`.
`.
`(73) Assignee: Apple Inc., Cupertino, CA (US)
`
`(*) Notice:
`
`Subject to any disclaimer, the term ofthis
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 1258 days.
`
`tees Coupet a eteeeeeeeeteenieey 343/702
`oteeas BI *
`ward et al.
`24;
`2/2005 Chang
`6,859,179 B2
`2/2006 H
`t
`al.
`6,995,716 B2
`4/2006 Wenet Al
`7,023,387 B2
`12/2009 Caballero et al.
`7,639,187 B2
`11/2002 Kasuyaet al.
`2002/0163472 Al
`8/2003 Bae sescscscssnsssenene 455/568
`2003/0157972 AL*
`11/2003 Swardet al.
`2003/0210199 AL
`2004/0203488 Al* 10/2004 Sullivan etal. oo... 455/90.1
`2005/0243015 Al
`11/2005 Kfoury etal.
`2007/0109204 Al*
`5/2007 Phillipsetal. ow. 343/702
`FOREIGN PATENT DOCUMENTS
`WO 99/41801
`8/1999
`WO 02/087011
`10/2002
`
`wo
`WO
`
`(21) Appl. No.: 11/651,094
`
`(22)
`
`Filed:
`
`Jan. 6, 2007
`
`(65)
`
`Prior Publication Data
`US 2008/0166004. Al
`Jul. 10, 2008
`Int.Cl
`(51)
`(2006.01)
`HOAB 1/38
`(52) U.S.C.
`....... 455/90.3; 455/90.2; 343/904; 381/375
`(58) Field of Classification Search
`455/90.2
`455/90 3. 343/904: 381 R75
`See applicationfile for com: lete search histo
`P
`ry:
`PP
`References Cited
`U.S. PATENT DOCUMENTS
`
`(56)
`
`2,931,115 A *
`5,440,315 A
`5,657,969 A
`5,710,987 A *
`5,748,150 A
`6,046,699 A
`6,097,339 A
`6,099,482 A *
`6,266,017 Bl
`6,509,876 Bl
`
`4/1960 Pesteretal. oo... 353/116
`8/1995 Wrightetal.
`8/1997 Bivens
`1/1998 Paulick wc. ee 455/575.7
`5/1998 Rudisill
`4/2000 Elliott et al.
`8/2000 Filipovicet al.
`8/2000 Bruneetal. ou. 600/549
`7/2001 Aldous
`1/2003 Jonesetal.
`
`* cited by examiner
`
`Primary Examiner — Lana N Le
`Assistant Examiner — Hsin-Chun Liao
`
`(74) Attorney, Agent, or Firm — Treyz Law Group; G.Victor
`Treyz; David C. Kell
`Teyés NI
`uke
`(57)
`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 antennastructure is mounted
`within a button structure. The button structure includes a
`switch actuation memberthat extends past the antenna struc-
`ture and into engagement with a switch. The switch actuation
`member may reciprocate within the button structure. A user
`maypress upon an exposed end ofthe switch actuation mem-
`ber 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 formingthe buttonstructure from dielectric, clear-
`ance is provided between the antenna structure and conduc-
`tive portions of the compact portable wireless device so that
`the antenna of the compactwireless device operates properly.
`
`16 Claims, 9 Drawing Sheets
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`FIG.8
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`1
`ANTENNA AND BUTTON ASSEMBLY FOR
`WIRELESS DEVICES
`
`BACKGROUND
`
`2
`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 movesalong
`the guide channel towards the switch. Raised structures such
`as ribs may be usedto ensure that the switch actuation mem-
`ber reciprocates smoothly within the guide channel.
`The wireless device may have a metal housing portion and
`Asintegrated circuit technology advances, it is becoming
`adielectric housing portion. The button may be formed within
`feasible to construct portable wireless devices with small
`the dielectric housing portion, so that the performanceof the
`form factors. Examples of portable wireless devices include
`antenna is not degraded.
`mobile telephones, wireless headsets, digital cameras with
`The antenna resonating element may be formed fromaflex
`wireless
`capabilities,
`remote controls, wristwatch-type
`circuit containing a strip of conductor. The flex circuit may be
`devices, music players with wireless functions, and handheld
`attachedto the button guide structure using adhesive. Theflex
`computers. Devices such as these are often small enough to be
`circuit may contain registration holes that mate with corre-
`held in the hand and may sometimesbe referred to as hand-
`sponding registration bosses. One or more of the bosses may
`held electronic devices. Larger portable wireless devices
`serve as heat stake bosses and may be heattreated to help
`include laptop computers.
`secure the flex circuit to the button guide structure.
`Portable electronic devices sometimes use antennas to
`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 pre-
`ferred embodiments.
`
`This invention relates generally to wireless communica-
`tions devices, and more particularly, to antenna and button
`structures for wireless communications devices.
`
`transmit and receive radio-frequency signals. For example,
`wireless Bluetooth headsets have antennas for communicat-
`
`20
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`BRIEF DESCRIPTION OF THE DRAWINGS
`
`25
`
`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
`
`ing with cellular telephones.
`For proper antenna operation, an antenna resonating ele-
`ment in a portable wireless device is generally placed at a
`suitable distance from the conductive structuresin the device.
`Sometimes antennas are mounted externally. This type of
`arrangement is used, for example, in certain cellular tele-
`phone whip antenna arrangements. When a more compact
`arrangementis 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 maintainedfree of electrical com-
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`compactportable wireless device using an antenna and button
`assembly in accordance with an embodimentofthe present
`invention.
`FIG.3 is an exploded perspective view of an antenna and
`button assembly in accordance with an embodimentof the
`ponents. If sufficient clearance is not providedfor the antenna
`present invention.
`resonating elementin this way, the antenna mayfail to operate
`FIG. 4 is a perspective view of an antenna and button
`properly.
`assembly in which a circuit board has been mounted to a
`In somesituations, it is not acceptable to use an external
`button guide and antenna support structure in accordance
`antenna design. Constraints such as a desire for compactness,
`with an embodimentof the present invention.
`light weight, and good esthetics can make external designs
`inappropriate. Similarly, antenna arrangements based on cir-
`FIG.5 is a top view of a portion of a printed circuit board
`
`cuit boards in whichalarge clearance is provided between an in an antenna and button assembly in accordance with an
`antenna resonating element and components mounted on the
`embodimentof the present invention.
`FIG. 6 is a cross-sectional side view of an illustrative
`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 com-
`munications devices.
`
`antenna and button assembly showing howelectrical contact
`for an antenna resonating element may be made using a spring
`conductor in accordance with an embodimentofthe present
`invention.
`
`SUMMARY
`
`In accordance with the present invention, wireless commu-
`nications devices are provided. For example, a compact por-
`table wireless device such as a wireless headset may be pro-
`vided. The compact portable wireless device may have a
`button. The button may be formed substantially from dielec-
`tric 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 ofthe antenna and helps to
`provide suitable clearance between the antenna resonating
`element and conductive structures in the compact portable
`wireless device.
`the button contains a
`With one suitable arrangement,
`switch such as a domeswitch. 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
`
`FIG.7 is a side view of an antenna and button assembly in
`accordance with an embodimentof the present invention.
`FIG. 8 is a top view of an illustrative flex circuit that
`includes a patterned antenna resonating element in accor-
`dance with an embodimentof the present invention.
`FIG.9 is an end view ofan illustrative antenna and button
`assembly showing howa flexcircuit 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
`compactportable wireless device. Compactportable wireless
`devices that may be used with the antenna and button arrange-
`ments of the invention include cellular telephones, remote
`controls, global positioning system devices, music players,
`portable computers, wrist devices, pendant devices, head-
`phone andearpiece devices, other wearable and miniature
`devices, and hybrid devices that include the functionality of
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`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 compactandlightweight
`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 ofhousing 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 con-
`structed from plastic or other suitable dielectric.
`The external equipment with which device 10 may com-
`municate 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 illus-
`trative Bluetooth headset arrangementofthe type that may be
`used for device 10 is described in concurrently-filed com-
`monly-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’s ear.
`In this position, end 28 of device 10 extends downward,
`towards the user’s mouth. Sound(e.g., from a telephonecall)
`maybe presentedto the user throughslots 18 of earbud 16. At
`end 28 of device 10, device 10 has a microphonethatresides
`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 member20 reciprocatesin direc-
`tions 22 along longitudinal axis 24 of device 10 (1.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 ofplastic 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 formedofplastic 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 withoutinter-
`ference button components.
`Across-sectional side view ofdevice 10 is shownin 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 andcircuit board 42. Electrical compo-
`nents may be mountedto circuit board 42 (e.g., battery pro-
`tection circuits, control circuits, etc.).
`One or morelight 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 secondportion 12-2. First portion 12-1 may be formed of
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`4
`aluminum,stainless steel, magnesium,titanium, other suit-
`able metals, alloys of these metals, and other suitable con-
`ductive materials. First housing portion 12-1 may also be
`formedpartly 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 conduc-
`tor 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
`mountedto printed circuit board 42. Coaxial cable 38 may be
`connectedto printed circuit board 34 using miniature coaxial
`cable connector 36.
`
`Printed circuit board 34 may contain electronic compo-
`nents such as radio-frequencytransceivercircuits. 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, transceivercircuitry 34 supports Bluetooth com-
`munications 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
`conducta telephonecall, speaker 32 may be usedto 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
`powerdevice 10.
`A switch such as switch 56 may be mountedto circuit
`board 42. Switch actuation member20 reciprocates in direc-
`tions 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., nor-
`mally open, normally closed, etc.) pressing against switch 56
`causes switch 56 to open or close. Electrical signals from
`switch 56 maybepassedto 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 oroff,
`resetting device 10, changing the modeofoperation 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, whichis described
`herein as an example, the guide structure includes portions
`that define a guide channel. Switch actuation member20 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 antennaof device 10 has a ground (sometimesreferred
`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
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`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 some-
`timesreferred to as the antenna of device 10, may be mounted
`to the guide structure or other suitable structure associated
`with button 30. Because thestructures that make up button 30
`are primarilyor entirely formedofdielectric, the antenna may
`function properly without interference from metal compo-
`nents 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 hous-
`ing portion 12-1 andthe 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
`suchasportion 12-2 that is more elongated along axial dimen-
`sion 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 accommo-
`date antenna spacing D. No space is wasted, because antenna
`resonating element 60 is mountedto 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 struc-
`ture for antenna resonating element 60, creates clearance
`between antenna resonating element 60 and conductive hous-
`ing 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 sometimescollectively 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 embodi-
`mentofbutton 30 is shown in FIG. 3. As shownin the example
`of FIG. 3, button 30 may have switch actuation member20,
`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 sur-
`faces 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 appearas 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 mayslide 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., ultravio-
`let-light cured epoxy) maybe 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
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`ensuresthatultraviolet 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 channel68 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 member20 pro-
`vide structural support for stem 86. Button guide structure 64
`mayhaverecesses that accommodate gussets 76 when switch
`actuation member20 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 maypress against surface 90 of switch 56or other
`suitable switch actuation surface. This closes or opensa cir-
`cuit betweena pair of contacts within switch 56 or otherwise
`operates the switch 56 sothat suitable actions may be taken by
`the control circuitry of device 10.
`Switch 56 maybea side-actuated domeswitch 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
`maysense 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 ele-
`ment 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 fre-
`quencies in the communications bandofinterest for device
`10. Conductive strips may be formed of metal or other suit-
`able conductors and maybestraight, 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 ofthese metals may be
`used to form antenna resonating element 90. If the metal or
`other conductor that is used to form antenna resonating ele-
`ment 90 has a tendency to oxidize upon exposure to air,
`encapsulant may be usedto ensure that the antenna resonating
`element 90 is hermetically sealed.
`Switch actuation member 20 mayhavea latch portion 74.
`During assembly, latch portion 74 is forced past a matching
`portion of button guide structure 64. Once past the matching
`portion ofbutton guide structure 64, switch actuation member
`20 and latch portion 74 snap into place. When switch actua-
`tion member 20 is withdrawn in direction 90, surface 92 of
`latch 74 catches on button guide structure 64, thereby pre-
`venting switch actuation member 20 from being removed
`from button 30.
`Switch actuation member 20 mayhave button headportion
`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 twodifferent 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
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`(sometimes
`copolymers
`acrylonitrile-butadiene-styrene
`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 formedofpolycarbonate
`(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,
`maybe formedas a unitary part with portion 80. By forming
`stem 86 from ABS plastic, potentially squeaky polycarbon-
`ate-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 ofthe blend may help
`housing portion 12-1 from becomingtoo brittle.
`Although shownas being formedfrom three separate plas-
`tic 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 mate-
`rials are insignificant when comparedto 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 ele-
`ment 60.
`
`Antenna resonating element 60 may be formedfrom 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 polyim-
`ide and other flexible substrates. Copper strips or other suit-
`able 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 guidestructure 64.
`If desired, the flex circuit or other suitable structure used
`for forming antenna resonating element 60 maybe 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 ele-
`ment 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 whichflex 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 whichflex circuit
`96 or another antenna structure is mounted within button
`
`guide support 64. Configurations in which antennaresonating
`element 60 is mounted to the exterior of button guide struc-
`ture 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 struc-
`ture 64. Bosses such as boss 100 mayserve both as registra-
`tion structures and as heat stake structures that are used to
`
`attach flex circuit 96 to button guide structure. When the
`bossesare usedas heat stake structures, heat is applied to the
`tips of the bosses. The heat deforms and enlarges the tips of
`the bossesso that the flex circuit 96 is retained. Flex circuit 96
`mayalso be affixed to outer surface 94 using adhesive. With
`one suitable arrangement,flex circuit 96 is formed from adhe-
`
`8
`sive-backedflex circuit material having multiple registration
`holes that mate with corresponding registration bosses on
`button guide structure 64. At least one of the registration
`bosses maybeheat treated to help secureflex circuit 96.
`A top view ofa portion ofcircuit board 42 in the vicinity of
`connector 40 is shown in FIG. 5. As shown in FIG. 5, con-
`nector 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 maybeelectrically connected to antenna resonat-
`ing element 60 by a spring or other suitable conductive path.
`Aschematic cross-sectional view ofbutton guide structure 64
`that shows how spring 110 may be used to interconnect pad
`106 on circuit board 42 with contact pad 112 onflex circuit 96
`is shown in FIG. 6. Contact pad 112 may be electrically
`connected to antenna resonating element 60. With one suit-
`able arrangement, antenna resonating element 60 is formed of
`copperand is coated with a sealing cap formed of solder mask
`material. The sealing cap can help to protect the copper ofthe
`antenna resonating element 60 from oxidation. A hole may be
`formedin the sealing cap to allow a gold plating to be formed
`for pad 112. Clip 110 maypress against pad 112, as shown
`schematically in FIG. 6. If desired, clip 110 can be wrapped
`tightly aroundthe exterior ofbutton 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
`shownin 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 ofbutton guidestructure 64
`whenflex circuit 96 is wrapped aroundbutton guidestructure.
`FIG. 8 showsa suitable shape that may be usedforflex circuit
`96 whenit is desired to wrap flex circuit 96 arounda slanted
`button guide structure of the type shown in FIG. 7. In the
`illustrative arrangement of FIG.8, flex circuit 96 has regis-
`tration holes 98 that may mate with corresponding bosses on
`button guide structure 64. Notch 114 may be used to accom-
`modate 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 offlex circuit 96 may be adjustedso 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
`member20 is movedin direction 88 towards switch 56 along
`axis 24.
`
`Boss 100 may be a heat s