PATENT DOCUMENT

Publication Number: US-9659723-B2
Application Number: US-201213478623-A
Country: US
Kind Code: B2

Title: Accessory controller with switch module

Abstract:
An accessory may be provided with a button controller having a microphone and switches. Plastic structures for the accessory may be formed by injection molding. Plastic structures may be molded around switch terminals. Switches may be formed using dome switch members and the switch terminals. A printed circuit with components may be mounted in the plastic structures. Recesses in the structures may be configured to receive the dome switch members, components on the printed circuit board, and wires in a cable. A backplate may be used to cover the printed circuit. A layer of plastic may be molded over the backplate to seal an interface created by the backplate. Cable strain relief structures may be molded into the layer of plastic. A lip on the strain relief structures may prevent particles from entering the controller.

Claims:
What is claimed is: 
     
       1. An accessory button controller, comprising:
 metal switch terminals embedded in at least one plastic structure; 
 wires soldered to the terminals; 
 at least one dome switch formed from a dome switch member and portions of the terminals, wherein the at least one plastic structure comprises a first plastic substructure encapsulating the metal switch terminals and a second plastic substructure coupled to the first plastic substructure, wherein the at least one plastic structure comprises a first recess in a first side of the at least one plastic structure configured to receive the dome switch member, a second recess in a second side of the at least one plastic structure configured to receive one or more electrical components, and a third recess configured to receive the wires; 
 a structure disposed over the second side of the at least one plastic structure, wherein the structure comprises a fourth recess; and 
 a strain relief structure comprising a third plastic substructure disposed at least partially within the fourth recess. 
 
     
     
       2. The accessory button controller defined in  claim 1  further comprising a cable that is received within the strain relief structure, the cable including multiple wires, the multiple wires including the wires that are soldered to the switch terminals. 
     
     
       3. The accessory button controller defined in  claim 1  wherein the strain relief structure comprises a fifth recess and a flexible lip positioned between the fifth recess and an end of the movable button member, wherein the movable button member is configured to bear against the flexible lip when the movable button member is pressed. 
     
     
       4. The accessory button controller defined in  claim 1  wherein the third recess is in the second side of the at least one plastic structure and extends along a length of the switch module. 
     
     
       5. The accessory button controller defined in  claim 1  wherein at least one metal switch terminal extends into the second recess and the wires are soldered to the at least one metal switch terminal in the second recess. 
     
     
       6. The accessory button controller defined in  claim 1  further comprising a printed circuit, wherein the one or more electrical components is electrically connected to the printed circuit. 
     
     
       7. The accessory button controller defined in  claim 6  further comprising a backplate disposed over the printed circuit and between the second side of the at least one plastic structure and the structure, wherein the backplate forms an interface with the second plastic substructure. 
     
     
       8. The accessory button controller defined in  claim 7  wherein the structure comprises a fourth plastic substructure that is coupled to the second plastic substructure and that seals the interface. 
     
     
       9. The accessory button controller defined in  claim 1  further comprising:
 a movable button member disposed over the switch module, wherein the button member comprises a button disposed over each dome switch; and 
 a clip attached to the movable button member and positioned between the button member and the switch module; 
 wherein the switch module, the backplate, and the structure are disposed within a housing member and the movable button member is attached to the housing member. 
 
     
     
       10. The accessory button controller defined in  claim 9  wherein the clip includes a first set of engagement features and the switch module includes a second set of engagement features, wherein each engagement feature in the first set of engagement features is configured to mate with a corresponding engagement feature in the second set of engagement features. 
     
     
       11. The accessory button controller defined in  claim 10  wherein the first set of engagement features comprise openings and the second set of engagement features comprise switch module protrusions protruding from the switch module. 
     
     
       12. An accessory button controller, comprising:
 a first housing component; 
 a second housing component positioned opposite the first housing component to define an interior volume of a housing; and 
 a plastic structure within the interior volume of the housing; 
 a first cable segment extending from a first end of the housing and comprising a first strain relief engaged with a first recess in the plastic structure; 
 a second cable segment extending from a second end of the housing and comprising a second strain relief engaged with a second recess in the plastic structure; and 
 a switch positioned in a third recess in the plastic structure and electrically coupled to at least one of the cable segments; wherein 
 the first housing component is configured to move relative to the second housing component to activate the switch. 
 
     
     
       13. The accessory button controller defined in  claim 12  further comprising a polymer film attached to the plastic structure over the first recess. 
     
     
       14. The accessory button controller defined in  claim 12 , further comprising metal structures embedded within the plastic structure. 
     
     
       15. The accessory button controller defined in  claim 14 , further comprising a dome switch member coupled to the plastic structure, wherein the metal structures are configured to form the switch with the dome switch member. 
     
     
       16. The accessory button controller of  claim 12 , wherein:
 the first strain relief is overmolded on the first cable segment; 
 the second strain relief is overmolded on the second cable segment; and 
 the first and second cable segments extend from opposite ends of the accessory button controller. 
 
     
     
       17. The accessory button controller of  claim 16 , wherein the first and second strain reliefs are substantially coaxial with one another. 
     
     
       18. The accessory button controller of  claim 17 , wherein:
 the plastic structure has a substantially elongate shape having a longitudinal axis extending from the first end to the second end; and 
 the first and second cable segments extend from opposite ends of the plastic structure and are substantially coaxial with the longitudinal axis of the plastic structure. 
 
     
     
       19. A headset, comprising:
 a button controller; 
 a first cable segment extending from a first end of the button controller and comprising a first strain relief proximate the first end of the button controller; 
 a second cable segment extending from a second end of the button controller and comprising a second strain relief proximate the second end of the button controller; 
 a speaker coupled to an end of the first cable segment; 
 a plug coupled to an end of the second cable segment and comprising at least two terminals; wherein 
 the button controller comprises:
 a first housing component; 
 a second housing component positioned opposite the first housing component to define an interior volume of a housing; 
 a plastic structure within the interior volume of the housing comprising a first recess, a second recess, and a third recess, the first strain relief engaged with the first recess and the second strain relief engaged with the second recess; and 
 a switch positioned in the third recess in the plastic structure, operatively coupled to at least the second cable segment, and configured to selectively electrically connect or disconnect a pair of the at least two terminals; 
 wherein the first housing component is configured to move relative to the second housing component to activate the switch. 
 
 
     
     
       20. The headset of  claim 19 , wherein the second and third recesses each define an undercut configured to retain the first and second strain reliefs, respectively, to the plastic structure. 
     
     
       21. The headset defined in  claim 19  wherein the switch comprises switch terminals embedded in the plastic structure. 
     
     
       22. The headset defined in  claim 21  wherein the switch further comprises a dome switch member in the first recess that is configured to form a dome switch with the switch terminals. 
     
     
       23. The headset defined in  claim 22  wherein the plastic structure comprises:
 a first shot of plastic in which the switch terminals are embedded; and 
 a second shot of plastic on the first shot of plastic. 
 
     
     
       24. Apparatus, comprising:
 switch terminals; 
 a plastic structure having the switch terminals molded at least partially therein, wherein the plastic structure forms at least one recess; 
 dome switches that each include a respective dome switch member configured to operatively interact with respective portions of the switch terminals; 
 a strain relief structure molded into the recess, comprising a flexible lip extending from the strain relief; and 
 a button member configured to bear against the flexible lip when the button member is pressed by a user. 
 
     
     
       25. The apparatus defined in  claim 24  further comprising:
 wires in the strain relief structure. 
 
     
     
       26. The apparatus defined in  claim 24 , wherein the plastic structure includes a first shot of plastic molded over the switch terminals and a second shot of plastic that has a groove configured to receive wires therein.

Description:
BACKGROUND 
     This relates to electronic devices, and more particularly, to accessories for electronic devices. 
     Electronic devices such as computers, media players, and cellular telephones typically contain user interface components that allow these devices to be controlled by a user. It is sometimes desirable to add accessories to electronic devices. For example, a user may desire to plug a headset or adapter accessory into an electronic device to allow the user to listen to audio. 
     Headsets are sometimes provided with buttons and microphones. A headset microphone may be used to pick up a user&#39;s voice during a telephone call. Buttons may be used to control media file playback, to make volume level adjustments during a telephone call, and to issue other commands for the electronic device. Buttons and a microphone may be mounted within a button controller assembly. Microphone signals and button signals may be routed from the button controller assembly to an electronic device using wires in the headset. 
     The designers of accessories and other electronic equipment are challenged with designing parts that are not overly complex or costly and that exhibit satisfactory reliability and performance 
     It would therefore be desirable to provide improved electronic device accessories such as accessories with button controller and microphone assemblies. 
     SUMMARY 
     An accessory may be provided with a button controller. The button controller may have a switch module that contains switches and a microphone. The switches may be formed from dome switch members. The microphone and other electrical components may be mounted within plastic structures. 
     The plastic structures may be formed using injection molding operations. For example, switch terminals for the switches may be formed by molding plastic around switch terminal structures. Switches may then be formed using dome switch members and the switch terminals. 
     A printed circuit with components may be mounted within the plastic structures. Recesses in the structures may be configured to receive the dome switch members, components on the printed circuit board, and wires in a cable. A backplate may be used to cover the printed circuit. A layer of plastic may be molded over the backplate to seal an interface created by the backplate. Cable strain relief structures may be molded into the layer of plastic. 
     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 diagram of a system including an electronic device and associated accessory in accordance with an embodiment of the present invention. 
         FIG. 2  is a wiring diagram for an illustrative accessory such as a pair of headphones with a button controller that has switches and a microphone in accordance with an embodiment of the present invention. 
         FIG. 3  is a cross-sectional side view of an illustrative button controller assembly for an accessory in accordance with an embodiment of the present invention. 
         FIG. 4  is a top view of switch terminal structures for a button controller assembly in accordance with an embodiment of the present invention. 
         FIG. 5  is a side view of switch terminal structures prior to injection molding of plastic structures in accordance with an embodiment of the present invention. 
         FIG. 6  is a cross-sectional side view of the switch terminal structures of  FIG. 5  in an insert molding tool in accordance with an embodiment of the present invention. 
         FIG. 7  is a cross-sectional side view of the switch terminal structures of  FIG. 6  following insert molding of a first shot of plastic and removal of excess terminal structure material in accordance with an embodiment of the present invention. 
         FIG. 8  is a cross-sectional side view of the switch terminal structures of  FIG. 7  in an insert molding tool in accordance with an embodiment of the present invention. 
         FIG. 9  is a cross-sectional side view of the switch terminal structures of  FIG. 8  following insert molding of a second shot of plastic in accordance with an embodiment of the present invention. 
         FIG. 10  is a cross-sectional side view of a partially assembled button controller assembly that has been provided with a dome switch member in accordance with an embodiment of the present invention. 
         FIG. 11  is a cross-sectional side view of the structures of  FIG. 10  following attachment of a printed circuit with components, wires, a backplate, and a flexible button cover layer in accordance with an embodiment of the present invention. 
         FIG. 12  is a cross-sectional side view of a portion of a strain relief structure for a switch module that has a barrier member for blocking material from entering the interior of the switch module in accordance with an embodiment of the present invention. 
         FIG. 13  is a cross-sectional side view of the portion of the strain relief structure of  FIG. 12  following pressing of a button member that compresses a flexible portion of the barrier member in accordance with an embodiment of the present invention. 
         FIG. 14  is a cross-sectional view of a portion of a switch module structure in accordance with an embodiment of the present invention. 
         FIG. 15  is a cross-sectional view of the button controller member of  FIG. 14  following insertion molding of a strain relief member into the switch module structure and around a cable with wires in accordance with an embodiment of the present invention. 
         FIG. 16  is a flow chart of illustrative steps involved in assembling a switch module in accordance with an embodiment of the present invention. 
         FIG. 17  is a perspective view of a button controller for an accessory in accordance with an embodiment of the present invention. 
         FIG. 18  is an exploded perspective view of a button controller in accordance with an embodiment of the present invention. 
         FIG. 19  is a perspective view of a switch module in a button controller following attachment of wire cables and strain relief structures in accordance with an embodiment of the present invention. 
         FIG. 20  is an exploded perspective view of a button controller in accordance with an embodiment of the present invention. 
         FIG. 21  is a perspective view of a switch module structure in accordance with an embodiment of the present invention. 
         FIG. 22  is an exploded perspective view of switch module structures in accordance with an embodiment of the present invention. 
         FIG. 23  is a rear perspective view of a switch module structure in accordance with an embodiment of the present invention. 
         FIG. 24  is a rear perspective view of the switch module structure of  FIG. 23  following attachment of wires in accordance with an embodiment of the present invention. 
         FIG. 25  is a rear perspective view of the switch module structures of  FIG. 24  following attachment of a printed circuit board in accordance with an embodiment of the present invention. 
         FIG. 26  is a rear perspective view of the switch module structures of  FIG. 25  following attachment of a backplate structure over the printed circuit board in accordance with an embodiment of the present invention. 
         FIG. 27  is a rear perspective view of the switch module structures of  FIG. 26  following overmolding of a shot of plastic in accordance with an embodiment of the present invention. 
         FIG. 28  is a rear perspective view of the switch module structures of  FIG. 27  following injection molding of a shot of plastic for a strain relief structure in accordance with an embodiment of the present invention. 
         FIG. 29  is a partially exploded front perspective view of the switch module structures of  FIG. 28  showing how the switch module structures may be mounted within upper and lower button controller housing structures in accordance with an embodiment of the present invention. 
         FIG. 30  is a cross-sectional view of an end portion of a button controller showing how a strain relief structure may be used to block intrusion of external material into the interior of the button controller in accordance with an embodiment of the present invention. 
         FIG. 31  is a flow chart of illustrative steps involved in forming button controller structures in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic components such as microphones and buttons may be used in a wide range of applications. For example, microphones and buttons may be used to form a button controller for a headset or other accessory. Button structures and microphone structures may, in general, be used in any suitable system. Button controller assemblies that are suitable for use in accessories such as electronic device headsets are sometimes described herein as an example. 
     An illustrative system in which an accessory may be used with an electronic device is shown in  FIG. 1 . As shown in  FIG. 1 , electronic device  10  may be coupled to an accessory such as headset  12  by plugging plug  16  of accessory  12  into jack  14  of electronic device  10 . 
     Electronic device  10  may be a computer such as a desktop computer, tablet computer, or laptop computer. Device  10  may also be a handheld electronic device such as a cellular telephone or media player, a tablet device, other portable electronic devices, or any other electronic equipment. Headset  12  may have speakers  18  and controller  22 . Controller  22  may have buttons and may therefore sometimes be referred to as a button controller or button controller assembly. Button controller  22  and speakers  18  may be coupled to device  10  using cable  20  (e.g., a three-wire or four-wire headset cable). Button controller  22  may, if desired, include a microphone. The microphone may be used by a user of device  10  and headset  12  during a telephone call (e.g., to pick up the user&#39;s voice). 
     Button controller  22  may include buttons such as buttons  24 ,  26 , and  28 . There may, in general, be any suitable number of buttons in button controller  22  (e.g., one or more buttons, two or more buttons, three or more buttons, etc.). With one suitable arrangement, which is sometimes described herein as an example, button controller  22  may include three buttons. These buttons may be used to issue commands for device  10 . Examples of commands that may be issued for device  10  using the buttons of button controller assembly  22  include stop, forward, and reverse commands, volume up and down commands, telephone call control commands, etc. 
     A wiring diagram of an illustrative accessory such as headset  12  of  FIG. 1  is shown in  FIG. 2 . As shown in  FIG. 2 , headset  12  may have wires in cables  20  that interconnect left speaker  18  (LS), right speaker  18  (RS), plug  16 , and button controller  22 . Two ground lines (G and G 2 ) may be coupled to a ground terminal in plug  16 . A microphone line (M), left speaker line (L), and right speaker line (R) may be coupled to a microphone terminal, left speaker terminal, and right speaker terminal in plug  16 , respectively. Ground line G 2  and microphone line M may terminate on terminals in button controller  22 . Ground line G and speaker line L may pass through the housing of button controller  22  to couple to speaker terminals in left speaker LS. Right speaker RS may have terminals that are coupled between right speaker line R and ground speaker line G. 
     A cross-sectional side view of structures in button controller  22  is shown in  FIG. 3 . As shown in  FIG. 3 , button controller  22  may have a dome switches formed from dome switch members such as dome switch members  30 . Each dome switch member may contact portions of terminal structures such a terminal structures  32 . Terminal structures  32  may be formed from metal and may be soldered to circuitry such as components  34  on printed circuit board  36  and to wires such as wires  38  in cable  20  using solder  40 . Dome switch members  30  may be received within recesses in plastic structure  46 . During operation, dome switch members  30  may be compressed by a user. When a dome switch member is compressed in this way, metal on the dome switch member can short together a corresponding pair of switch terminal structures (i.e., each dome switch is formed from a corresponding dome switch member  30  and portions of associated terminals structures  32 ). 
     Flexible plastic sheet  42  may cover dome switch members  30 . Structures  44  may be formed from a material such as epoxy and may be used to create a structure against which an overlying plastic button member may bear when actuating the switches formed by dome switch members  30 . Plastic structure  46  may have upper recesses such as dome switch member recesses  48  for receiving dome switch members  30  and may have lower recesses such as lower recesses  50  for receiving components such as a microphone (MIC) and other electrical components  34  on printed circuit board  36 . A planar member such as a sheet of plastic or metal such as backplate  51  may be used to cover recesses such as recesses  50  on the rear of structures  46 . 
     Multiple injection-molded plastic structures (sometimes referred to as “shots” of plastic) may be used in forming button controller structures. For example, a shot of plastic may be used in forming plastic structure  46  and a shot of plastic may be used in forming additional structures such as structure  52 . Wires  38  may be secured within a groove in a plastic structure such as structure  52  using adhesive  54  or other suitable attachment mechanisms. 
     Switch terminals such as terminals  32  may be formed from a patterned metal part.  FIG. 4  is a top view of switch terminal structures  32 ′ for a button controller assembly. As shown in  FIG. 4 , switch terminal structures  32 ′ may form a frame for holding switch terminals in place during injection molding of plastic structures  46 . Following injection molding of plastic structures  46  over the metal that forms switch terminals  32  of  FIG. 3 , exterior portions of structures  32 ′ may be removed from the portions of structures  32 ′ that lie within structures  46 . For example, structures  32 ′ may be cut along lines  56 , leaving terminal structures  32  embedded within structures  46 . 
     The interior components of button controller  22  that are used in forming switches and associated mounting structures may sometimes be referred to as switch module structures or a switch module. A switch module for button controller  22  may be formed by injection molding multiple plastic structures onto each other. Illustrative operations involved in forming a switch module using injection molding techniques are shown in  FIGS. 5, 6, 7, 8, and 9 . 
     Initially, as shown in  FIG. 5 , switch terminal structures  32  may be formed (e.g., by stamping, machining, or otherwise patterning a sheet of metal or other suitable conductive material). 
     As shown in  FIG. 6 , metal parts for forming switch terminals structures  32  may be placed in cavity  60  of molding tool  58 . 
     During a first injection molding operation, plastic (e.g., a first shot of plastic) may be injection molded into cavity  60  over the switch terminal structures to form injection-molded (insert-molded) plastic structures such as structures  46  of  FIG. 7 . Portions  62  of the terminal structures may then be removed to form terminal structures  32  of  FIG. 8  (e.g., by stamping, sawing, breaking, or other suitable techniques). 
     Following removal of plastic structures  46  from injection molding tool  58 , structures  46  (and embedded switch terminal structures  32 ) may be placed in a different mold cavity, such as mold cavity  68  in injection molding tool  64  of  FIG. 8 . Molding tool  64  may be formed using different equipment from tool  58  or tools  64  and  58  may be part of the same system. During a second injection molding operation, a second shot of plastic may be injected into mold cavity  68  (e.g., via injection port  66 ), as shown in  FIG. 8 . 
     The second injection molding operation may be used to form a plastic structure such as plastic structure  52  on structures  32  and  46 , as shown in  FIG. 9 . If desired, structures  52  may include recesses or other features for receiving components as part of a button controller assembly process. As an example, structures  52  may include a recess such as recess  70  (e.g., a groove) for receiving wires in cable  20 . Structures  52  may also include lower recesses such as recess  50  for receiving components  34  ( FIG. 3 ), features for forming recesses for receiving switch components, etc. 
       FIG. 10  shows how a switch component such as dome switch member  30  may be placed in recess  48 . Recess  48  may be formed in structures  46  and/or  52  or other plastic switch module structures. Portions of switch terminals  32  may contact metal in dome switch members  30  during operation. By using a second shot of plastic such as shot  52 , these portions of metal may be environmentally sealed. The recesses in which dome switch members  30  are received may be sealed using a plastic sheet. For example, a cover layer such as flexible plastic sheet  42  may be attached to structure  52  over dome switch members  30  using adhesive  74 .  FIG. 11  shows how wires  38  may be secured in groove  70  using adhesive  54 . Components  34  on printed circuit  36  may be received within recess  50 . Backplate  51  may be attached to structures  52  using adhesive  74 , thereby enclosing printed circuit  36  and components  34 . 
     The structures of  FIG. 11  may form a switch module for button controller  22 . A cover member and rear housing member may be used as housing structures to enclose the switch module. A strain relief structure may be used to hold cable  20  to the button controller. To prevent external material such as dust particles from entering into the interior of button controller  22 , the strain relief structure and/or other structures in button controller  22  may be provided with particle blocking features such as flexible lip structures. 
     As an example, consider the cross-sectional side view of button member  80  and strain relief member  82  of  FIG. 12 . Strain relief member  82  may be formed from an elastomeric plastic that is configured to provide strain relief to cable  20 . Button member  80  may serve as a cover structure that covers the structures of the switch module of  FIG. 11 . When pressed inwardly by a user (down in the orientation of  FIG. 12 ), button member  80  may actuate a corresponding one of the dome switches formed using dome switch members  30 . Button member  80  may be formed from a plastic that is sufficiently flexible to ensure that the operation of pressing one button member does not inadvertently actuate adjacent switches. During operation, button member  80  may move between an unactuated position (when not pressed by a user) and an actuated position (when pressed downwards towards underlying switches by a user). 
     As shown in  FIG. 12 , in its unactuated position, button member  80  may not be perfectly flush with the surface of strain relief structure  82 . As a result, there is a potential for debris to enter into interior region  94  of button controller  22  from exterior region  96  through gap  92 . To prevent material from entering into region  94  through gaps such as gap  92 , strain relief structure  82  or other suitable button controller structures may be provided with a protruding structure such as flexible lip  84 . A protrusion such as flexible lip  84  may be formed from a material with sufficient elasticity to bend when button member  80  is pressed and bears against lip  84 . Recess  86  in strain relief structure  82  may help allow lip structure  84  to deform. 
     As shown in  FIG. 13 , when button member  80  is pressed downwards in direction  88  by a user, lip  90  may bend in direction  90 . The presence of recess  86  may help accommodate bending lip structure  84 . In both the unactuated position of  FIG. 12  and the actuated position of  FIG. 13 , lip  84  may touch (or nearly touch) member  80 , thereby helping to block debris and forming a seal between exterior region  96  and interior region  94 . 
       FIG. 14  is a top view of an end portion of plastic button controller structures such as plastic molded structure  120  showing how a recess such as recess  98  may be formed to receive and engage an overmolded strain relief structure. As shown in  FIG. 15 , when a strain relief structure such as structure  82  has been formed, cable  20  may be held in place on button controller  22 . 
       FIG. 16  is a flow chart of illustrative steps involved in assembling a switch module for a button controller such as button controller  22 . At step  100 , an insert molding tool such as tool  58  of  FIG. 6  may be used to mold plastic for structures  46  over a metal switch terminal structure such as structures for forming switch terminals  32  of  FIG. 3 . Tool  58  may have a mold cavity configured to form molded plastic structure  46  of  FIG. 3 . Terminal structures  32  may be held in place as part of a metal frame structure such as frame structure  32 ′ of  FIG. 4 . Features such as dome switch member recesses  48  and component recesses  50  may, if desired, be incorporated into plastic structures  46 . 
     At step  102 , the switch terminal structures with the molded plastic may be removed from the remainder of the switch terminal structures (i.e., the switch terminal structures may be cut along lines  56  of  FIG. 4  to release the individual switch terminal structures  32  from frame structures  32 ′). 
     At step  104 , a second shot of plastic may be overmolded on top of the first shot of plastic using an injection molding tool such as tool  64  of  FIG. 8 . During the operations of step  104 , structures such as structures  52  from the second shot of plastic may be molded over structures such as structures  46  from the first shot of plastic (see, e.g.,  FIG. 9 ). Features such as wire retention groove  70  ( FIG. 11 ) may be molded into structures  52  during the operations of step  104 , if desired. 
     During the operations of step  106 , switch module structures such as dome switch members  30  may be installed in recesses such as recesses  48  and polymer film  42  may be used to cover dome switch members  30  and recesses  48 , thereby forming a switch module for use in button controller  22 . 
     Following formation of the switch module, the switch module and additional button controller structures may be assembled to form a completed button controller in a headset or other accessory. 
       FIG. 17  is a perspective view of an illustrative button controller for an accessory. As shown in  FIG. 17 , button controller  22  may have a housing formed from lower housing member  108  and button member  80 . Buttons such as buttons  28 ,  26 , and  24  may be formed from flexible portions of member  80  overlapping corresponding switches in the switch module. 
     An exploded perspective view of button controller  22  is shown in  FIG. 18 . As shown in  FIG. 18 , button controller  22  may include a switch module such as switch module  116 . Switch module  116  may be formed using operations of the type described in connection with  FIG. 16 . Switch module  116  may, for example, have dome switches that are covered with flexible plastic layer  42 . Each dome switch may have a corresponding switch protrusion such as switch protrusion  44 . Strain relief structures  82  may be used to help guide cable  20  into switch module  116 . 
     Adhesive such as pressure sensitive adhesive  110  or other fastening mechanisms may be used to attach lower controller housing structure  108  to switch module  116 . Metal clip  112  may be attached to button member  80  using heat stakes or other suitable attachment mechanisms. Clip  112  may have engagement features such as opening  118  that mate with corresponding engagement features on switch module  116  such as switch module protrusions  114  on plastic structure  52  (sometimes referred to as snaps). 
       FIG. 19  is a perspective view of switch module  116  prior to assembly with the components of  FIG. 18  to form button controller  22 . 
       FIG. 20  is an exploded perspective view of a switch module such as switch module  116  of  FIG. 19 . As shown in  FIG. 20 , switch module  116  may include a printed circuit such as printed circuit  36 . Printed circuit  36  may be a rigid printed circuit board such as a board formed from fiberglass-filled epoxy (e.g., an FR4 board) or may be a flexible printed circuit (“flex circuit”) formed from a sheet of polyimide or other flexible polymer. Components such as components  34  may be mounted on printed circuit  36 . 
     Switch module  116  of  FIG. 20  may also include backplate  51 . Plastic molded structure  120  may be formed from an additional shot of plastic (i.e., an overmolded structure formed from a third shot of plastic that covers the structures formed from first plastic shot  46  and second plastic shot  52 ). Molded structures  120  may cover backplate  51 . 
       FIG. 21  is a switch module structure formed from polymer film  44  that covers plastic structures such as structures  52  and  46 . 
       FIG. 22  is a front exploded perspective view of switch module structures in switch module  116 . As shown in  FIG. 22 , switch module  116  may include protruding portions (e.g., epoxy structures) on polymer film  42 , underlying dome switch members  30 , and structures  122  for receiving dome switch members  30 . Structures  122  may include structures  46  and structures  52 . 
       FIG. 23  is a rear perspective view of switch module structures  122 , showing how structures  122  may have exposed terminals such as terminals  124  that are accessible through openings in plastic structure  52 . 
       FIG. 24  is a rear perspective view of the switch module structure of  FIG. 23  showing how wires  38  may be press fit into groove  70  in plastic structure  52 . Bare ends of the G 2  and M wires ( FIG. 2 ) may be soldered to switch terminal structures  32 . 
       FIG. 25  is a rear perspective view of the switch module structures of  FIG. 24  following attachment of printed circuit  36 . Solder may be used to electrically connect circuitry on printed circuit  36  to switch terminal structures  32 . A heated tool (e.g., a hot bar structure) or other equipment may be used to reflow the solder used in connecting printed circuit  36  to switch terminal structures  32 . 
     Following attachment of printed circuit  36 , backplate  51  may be attached to switch module structures  116 , as shown in the rear perspective view of the switch module structures in  FIG. 26 . 
       FIG. 27  is a rear perspective view of the switch module structures of  FIG. 26  following overmolding of a shot of plastic to form overmold structures  120 . Portions of backplate  51  may be visible through openings in structures  120 . Overmolded structures  120  may help seal the interface between backplate  51  and plastic structures  52  ( FIG. 26 ). Overmold  120  may also retain wires  22  and cable  20  and may cover recess  70 . 
       FIG. 28  is a rear perspective view of the switch module structures of  FIG. 27  following injection molding of a shot of plastic to form strain relief structures  82 . The plastic material used to form strain relief structures  82  may be, for example, a soft elastomeric material such as thermoplastic polyurethane. Illustrative materials for forming the other plastic structures in button controller  22  include polycarbonate (PC), acrylonitrile butadiene styrene (ABS), PC/ABS blends, polypropylene, and other moldable plastics (as examples). Other types of plastic may be used, if desired. 
       FIG. 29  is a partially exploded front perspective view of the switch module structures of  FIG. 28  showing how the switch module structures may be mounted within upper and lower button controller housing structures such as structures  80  and  108 . 
       FIG. 30  is a cross-sectional view of an end portion of button controller  22  showing how strain relief structure  82  may have a flexible protrusion such as protrusion (lip)  84  for preventing intrusion of external material  130  into interior  94  of the button controller  22 . 
     A flow chart of illustrative steps involved in forming an accessory button controller is shown in  FIG. 31 . 
     At step  132 , operations of the type shown in  FIG. 16  may be used to form a switch module such as switch module  116  of  FIG. 23 . Switch module  116  may include a first shot of plastic such as structures  46  that encapsulates switch terminal structures  32  and may have a second shot of plastic that forms structures  52  on structures  46 . 
     At step  134 , wires  38  may be installed in switch module  116 . For example, wires  38  such as wires G and L of  FIG. 2  may be press fit into groove  70  of plastic structures  52  and the tips of wires G 2  and M may be soldered to metal structures  32 , to form switch module structures  116  of  FIG. 24 . 
     At step  136 , printed circuit  36  may be soldered to switch terminals  32  to form structures  116  of  FIG. 25 . 
     At step  138 , backplate  51  may be attached to printed circuit  36  to form structures  116  of  FIG. 26 . 
     At step  140 , plastic structures  120  may be overmolded over plastic structures  52  and the other structures of switch module  116  of  FIG. 27 , thereby forming switch module structures  116  of  FIG. 28 . During the operations of step  138 , an interface may be created between backplate  51  and second shot plastic structures  52 . Overmold structures  120  may seal this interface between structures  52  and backplate  51 . During the overmolding operations of step  140 , a material such as polypropylene which is able to readily flow into thin gaps may be used (e.g., a third shot of plastic applied to the structures of module  116  may be polypropylene), thereby helping to form an environmental seal for the interface between structures  52  and  51 . 
     At step  142 , strain relief structures (e.g., a fourth shot of plastic) such as structures  82  may be injection molded onto structures  120 , thereby forming the inner switch module assembly of  FIG. 28 . 
     At step  144 , button member  80  may be attached to clip  112  ( FIG. 18 ) by heat staking or other attachment mechanisms. 
     At step  146 , button member  80  may be pressed onto the assembly of  FIG. 28 , so that openings  118  of clip  112  snap onto snaps  114  on structures  52 . 
     At step  148 , bottom button controller housing member  108  may be attached to the assembly of  FIG. 28  using heat stakes, pressure sensitive adhesive, and/or other attachment mechanisms, thereby forming the structure of  FIG. 29 . 
     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: 20120523
Publication Date: 20170523
Grant Date: 20170523
Priority Date: 20120523
Inventors: YABE OSAMU
STANLEY CRAIG M.
STIEHL KURT R.
PREST CHRISTOPHER D.
Assignee: APPLE INC
CPC Classifications: [{"code": "H01H2229/044", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01H2233/002", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01H13/705", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01H2229/044", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01H13/705", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01H2233/002", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 49620737