PATENT DOCUMENT

Publication Number: US-9454177-B2
Application Number: US-201414181518-A
Country: US
Kind Code: B2

Title: Electronic devices with housing-based interconnects and coupling structures

Abstract:
An electronic device has an electronic device housing containing electrical components such as integrated circuits and other components. The electronic device housing may be provided with an interconnect stack that has layers of dielectric and metal traces forming signal paths. Electrical components may be mounted on printed circuits. Coupling structures such as screws or other fasteners, washers, standoffs, nuts, springs, and spring-loaded pins may be used in forming signal paths that couple the signal paths of the interconnect stack to components such as buttons, batteries, printed circuits with integrated circuits, displays, and other circuitry.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 an electronic device housing having an inner surface; 
 an interconnect stack on the inner surface that includes a signal line formed from a metal trace; 
 an electrical component; and 
 a coupling structure that electrically couples the signal line to the electrical component, wherein the coupling structure comprises a fastener, wherein the fastener has at least two parallel signal paths that are isolated from each other by dielectric, wherein the fastener has first and second opposing sides, wherein a first signal path of the at least two parallel signal paths is formed on the first side of the fastener, wherein a second signal path of the at least two parallel signal paths is formed on the second side of the fastener, and wherein the dielectric is interposed between the first and second signal paths. 
 
     
     
       2. The electronic device defined in  claim 1  further comprising a printed circuit to which the electrical component is mounted. 
     
     
       3. The electronic device defined in  claim 1  wherein the electrical component comprises a battery. 
     
     
       4. The electronic device defined in  claim 1  wherein the electrical component comprises a button. 
     
     
       5. The electronic device defined in  claim 4  wherein the housing has an opening and wherein the button has a button member that passes through the opening. 
     
     
       6. The electronic device defined in  claim 1  wherein the housing is a metal housing. 
     
     
       7. An electronic device, comprising:
 an electronic device housing having an inner surface; 
 an interconnect stack on the inner surface that includes a signal line formed from a metal trace; 
 an electrical component; and 
 a coupling structure that electrically couples the signal line to the electrical component, wherein the interconnect stack has a right-angle bend that follows a right-angle bend in the electronic device housing. 
 
     
     
       8. An electronic device, comprising:
 an electronic device housing having an inner surface; 
 an interconnect stack on the inner surface that includes a signal line formed from a metal trace; 
 an electrical component; and 
 a coupling structure that electrically couples the signal line to the electrical component, wherein the housing has a protruding portion and wherein the interconnect stack comprises layers of material on the protruding portion. 
 
     
     
       9. An electronic device, comprising:
 an electronic device housing having an inner surface; 
 an interconnect stack on the inner surface that includes a signal line formed from a metal trace; 
 an electrical component; and 
 a coupling structure that electrically couples the signal line to the electrical component, wherein the coupling structure comprises a fastener, wherein the fastener has at least two parallel signal paths that are isolated from each other by dielectric, wherein the interconnect stack on the inner surface includes an additional signal line formed from an additional metal trace, wherein a first signal path of the at least two parallel signal paths is directly coupled to the signal line, and wherein a second signal path of the at least two parallel signal paths is directly coupled to the additional signal line.

Description:
BACKGROUND 
     This relates generally to electronic devices and, more particularly, to interconnecting electrical components in electronic devices. 
     Electronic devices include integrated circuits and other electronic components. These components are mounted on printed circuit boards. Metal lines in the printed circuit boards serve as signal paths. The signal paths, which are sometimes referred to as interconnects, are used to route data and power signals between the integrated circuits and other electronic components in an electronic device. 
     The printed circuit boards and interconnect structures that are used in an electronic device can have a significant impact on device size and performance. If care is not taken, device housings will be bulkier that desired and printed circuit board interconnect structures will be more complex and costly than desired. Interconnects formed from thin flexible printed circuits may help minimize device bulk, but may be susceptible to damage on sharp internal housing features and may not be sufficiently compact for some applications. 
     It would therefore be desirable to be able to provide electronic devices with improved interconnect structures. 
     SUMMARY 
     An electronic device may have electrical components mounted within an electronic device housing. The electrical components may include integrated circuits and other circuitry mounted to a printed circuit board, display components, buttons, batteries, and other electrical components. 
     The electronic device housing may be formed from a material such as plastic, metal, fiber-based composite material, or other material. The housing may have an interior surface. Signal paths may be formed within an interconnect stack that is formed directly on the interior surface of the housing. The interconnect stack may have layers of dielectric and patterned metal traces. 
     Coupling structures such as screws or other fasteners, washers, springs, and spring-loaded pins may be used in forming signal paths that couple the signal paths of the interconnect stack to signal paths associated components such as buttons, batteries, printed circuits with integrated circuits, displays, and other circuitry. As an example, a screw, spring-loaded pin, or other structure may be segmented to form multiple parallel signal paths, each of which is coupled between a respective metal trace in the interconnect stack and a respective signal path on a printed circuit or other electrical component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device such as a laptop computer in accordance with an embodiment. 
         FIG. 2  is a perspective view of an illustrative electronic device such as a handheld electronic device in accordance with an embodiment. 
         FIG. 3  is a perspective view of an illustrative electronic device such as a tablet computer in accordance with an embodiment. 
         FIG. 4  is a perspective view of an illustrative electronic device such as a display for a computer or television in accordance with an embodiment. 
         FIG. 5  is a cross-sectional side view of an electronic device in accordance with an embodiment. 
         FIG. 6  is a cross-sectional side view of a portion of an electronic device housing on which interconnect layers have been formed in accordance with an embodiment. 
         FIG. 7  is a cross-sectional side view of a portion of an electronic device housing on which interconnects that include vias and patterned signals lines have been formed in an electronic device housing in accordance with an embodiment. 
         FIG. 8  is a diagram of system equipment that may be used in forming electronic devices having interconnects based on housing structures, fasteners, and other structures in accordance with an embodiment. 
         FIG. 9  is a side view of a portion of an electronic device housing showing how housing-based interconnects may be mated with corresponding spring contacts on a battery or other electrical component in accordance with an embodiment. 
         FIG. 10  is a cross-sectional side view of a solid screw in accordance with an embodiment. 
         FIG. 11  is a cross-sectional side view of an illustrative screw with a core and a coating formed of different materials in accordance with an embodiment. 
         FIG. 12  is a cross-sectional side view of an illustrative screw having a coating such as an insulating coating over a portion of a shaft of the screw in accordance with an embodiment. 
         FIG. 13  is a cross-sectional side view of an illustrative housing with signal lines coupled to traces on a printed circuit via respective screws in accordance with an embodiment. 
         FIG. 14  is a cross-sectional side view of a portion of a printed circuit board and a component mounted to the printed circuit board showing how a screw with multiple signals paths may be used to couple the component and printed circuit to signal lines on an electronic device housing in accordance with an embodiment. 
         FIG. 15  is a perspective view of an illustrative screw that includes two independent signal paths in accordance with an embodiment. 
         FIG. 16  is a cross-sectional side view of an illustrative printed circuit that has been coupled to signal paths on an electronic device housing using a screw of the type shown in  FIG. 15  in accordance with an embodiment. 
         FIG. 17  is a top view of an illustrative screw that has been segmented to form two parallel independent signal paths in accordance with an embodiment. 
         FIG. 18  is a cross-sectional side view of an illustrative spring-loaded pin that is being used to interconnect a printed circuit to signal paths on an electronic device housing in accordance with an embodiment. 
         FIG. 19  is a perspective view of an illustrative spring-loaded pin that has four signal paths running along its length in accordance with an embodiment. 
         FIG. 20  is a top view of an illustrative spring-loaded pin that is engaging a notch in a structure such as a screw in accordance with an embodiment. 
         FIG. 21  is a top view of an illustrative spring-loaded pin that is passing through a hole in a structure such as a screw in accordance with an embodiment. 
         FIG. 22  is a top view of an illustrative segmented structure such as a segmented screw that has four portions each of which has a notch that receives a respective shaft of a spring-loaded pin in accordance with an embodiment. 
         FIG. 23  is a cross-sectional side view of an illustrative electronic device in which printed circuits and other structures have been coupled to signal paths on a housing of the electronic device using springs in accordance with an embodiment. 
         FIG. 24  is a cross-sectional side view of an illustrative electronic device housing with signal paths coupled to a button in accordance with an embodiment. 
         FIG. 25  is a cross-sectional side view of an illustrative button member passing through a housing wall in an electronic device to engage a button switch mounted on a printed circuit that is coupled to signal paths on the housing wall in accordance with an embodiment. 
         FIG. 26  is a cross-sectional side view of a portion of an illustrative electronic device housing having a channel filled with dielectric and conductive material to form a signal path in accordance with an embodiment. 
         FIG. 27  is a perspective view of an illustrative electronic device housing having a signal path coupled to a printed circuit using a spring-loaded pin in accordance with an embodiment. 
         FIG. 28  is a perspective view of an illustrative electronic device having spring-loaded pins at different heights along a housing wall to couple housing-based signal paths to printed circuit paths or other signal paths in accordance with an embodiment. 
         FIG. 29  is a cross-sectional side view of an illustrative electronic device housing wall coupled to a printed circuit using spring-loaded pins at different positions on the housing wall in accordance with an embodiment. 
         FIG. 30  is a perspective view of an illustrative electronic device having spring-loaded pins at different lateral locations along a housing wall to couple housing-based signal paths to printed circuit paths or other signal paths in accordance with an embodiment. 
         FIG. 31  is a cross-sectional side view of an illustrative printed circuit coupled to signal paths on an electronic device housing using a segmented gasket with respective signal paths in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may be provided with housings. Electrical components may be mounted within the housings on substrates such as printed circuits. An electronic device may have signal paths formed from metal lines on a housing. Fasteners such as screws, nuts, gaskets, standoffs, springs, spring-loaded pins, and other coupling structures may be used to couple metal traces on printed circuits to metal traces on a housing. The fasteners and other coupling structures may, if desired, contain multiple signal paths for routing more than one signal at a time. The signals that are carried between electrical components by the signal paths on the housing, by the signal paths in the coupling structures, and by signal paths in the printed circuits may be data signals, power signals, analog signals, digital signals, or other suitable electrical signals. 
     Electrical components may be coupled to signal paths using solder, spring-based structures such as springs or spring-loaded pins, conductive adhesive, direct contact between metal traces, or other suitable coupling mechanisms. 
     Illustrative electronic devices that have housings, printed circuits, and coupling structures that may be provided with signal paths for interconnecting electrical components are shown in  FIGS. 1, 2, 3, and 4 . 
     Electronic device  10  of  FIG. 1  has the shape of a laptop computer (portable computer) and has a portable computer housing  12  formed from upper housing  12 A and lower housing  12 B with components such as keyboard  16  and touchpad  18 . Device  10  has hinge structures  20  (sometimes referred to as a clutch barrel) to allow upper housing  12 A to rotate in directions  22  about rotational axis  24  relative to lower housing  12 B. Display  14  is mounted in housing  12 A. Upper housing  12 A, which may sometimes be referred to as a display housing or lid, is placed in a closed position by rotating upper housing  12 A towards lower housing  12 B about rotational axis  24 . 
       FIG. 2  shows an illustrative configuration for electronic device  10  based on a handheld device such as a cellular telephone, music player, gaming device, navigation unit, or other compact device. In this type of configuration for device  10 , device  10  (e.g., a cellular telephone) has opposing front and rear sides. Display  14  is mounted on a front face of device  10 . Housing  12  may have a planar surface on the opposing rear face of device  10 . Display  14  may have an exterior layer that includes openings for components such as button  26  and speaker port  28 . 
     In the example of  FIG. 3 , electronic device  10  is a tablet computer. In electronic device  10  of  FIG. 3 , tablet computer  10  has opposing planar front and rear surfaces. Display  14  is mounted on the front surface of device  10 . Housing  12  may have a planar rear wall on the opposing rear surface of device  10 . As shown in  FIG. 3 , display  14  has an external layer with an opening to accommodate button  26 . 
       FIG. 4  shows an illustrative configuration for electronic device  10  in which device  10  is a computer display, a computer that has an integrated computer display, or a television. Display  14  is mounted on a front face of device  10 . With this type of arrangement, housing  12  for device  10  may be mounted on a wall or may have an optional structure such as support stand  30  to support device  10  on a flat surface such as a table top or desk. 
     Housing  12  in device  10  (e.g., housing  12  in devices of the type shown in  FIGS. 1, 2, 3 , and  4  and other electronic devices) may be provided with signal paths (sometimes referred to as interconnects or interconnect paths) for routing signals between electrical components in device  10 . The signal paths may be formed from conductive metal signal lines. The conductive metal signal lines may be formed by photolithographic techniques, laser patterning, screen printing, pad printing, ink jet deposition, or other deposition and patterning techniques. Signal paths may be formed on the inner surfaces of housing  12  and may, if desired, be embedded within channels formed in housing  12 . Coupling structures such as screws and other fasteners, gaskets, standoffs, nuts, springs, spring-loaded pins, and other spring-based coupling structures may be used to couple signal paths on housing  12  to signal paths in electrical components and signal paths on printed circuits to which electrical components are mounted. 
     A cross-sectional side view of an illustrative electronic device of the type that may be provided with signal lines on the inner surfaces of housing  12  and in channels in housing  12  is shown in  FIG. 5 . As shown in  FIG. 5 , display  14  may be formed from a display module such as display module  42  mounted under a cover layer such as display cover layer  40  (as an example). Display  14  (e.g., display module  42 ) may be a liquid crystal display, an organic light-emitting diode display, a plasma display, an electrophoretic display, a display that is insensitive to touch, a touch sensitive display that incorporates and array of capacitive touch sensor electrodes or other touch sensor structures, or may be any other type of suitable display. Display cover layer  40  may be layer of clear glass, a transparent plastic member, or other clear structure. 
     Device  10  may have inner housing structures that provide additional structural support to device  10  and/or that serve as mounting platforms for printed circuits and other structures. Structural internal housing members may sometimes be referred to as housing structures and may be considered to form part of housing  12 . 
     Electrical components  48  may be mounted within the interior of housing  12 . Components  48  may be mounted to inner surfaces of housing  12  and may be mounted to substrates that contain signal paths. As shown in  FIG. 5 , for example, components  48  may be mounted to printed circuit boards such as printed circuit boards  46 . Printed circuit boards  46  may include rigid printed circuit boards (e.g., printed circuit boards formed from fiberglass-filled epoxy or other rigid printed circuit board material) and flexible printed circuits (e.g., flex circuits formed from sheets of polyimide or other flexible polymer layers). Patterned metal traces  52  within printed circuit boards  46  may be used to form signal paths between components  48 . Conductive signal paths such as conductive signal paths  50  (e.g., metal lines) may also be formed in housing  12  (e.g., on interior housing surfaces or embedded within housing  12 ). Conductive signal paths  50  (sometimes referred to as interconnects or interconnect paths) may, for example, be formed from metal signal lines on in an interconnect stack formed on inner surface  54  of rear housing wall  12 ′ and/or on inner surface  56  of housing sidewalls such as sidewall  12 ″ or on other housing surfaces. 
     Signal paths such as paths  50  may be used to interconnect substrates such as printed circuits  46 , thereby interconnecting electrical components such as components  48  on printed circuits  46 . Signal paths such as paths  50  may also be used to interconnect components  48  on printed circuits  46  with other electrical components in device  10 , such as batteries, displays, buttons, sensors, connectors, etc. As an example, conductive paths  50  (e.g., metal traces on housing  12 ) may be electrically coupled to components such as component  44  (e.g., a battery or other electrical device) and components such as display  14  (e.g., display module  42 ). Other electrical components may be coupled to components  48  and each other if desired. Electrical paths for coupling components together may include paths on printed circuits such as paths  52 , housing-based paths such as paths  50 , paths within components  48 ,  44 , and  42 , and signal paths in signal coupling structures. The coupling structures may be used to couple signal paths together (e.g., to couple paths  52  to paths  50 , to couple paths in components such as components  44  and  40  to paths  50 , etc.). Coupling structures can be based on screws or other fasteners, nuts, gaskets, standoffs, spring-based coupling structures such as spring-loaded pins, or other structures that include conductive structures that serve as signal paths. 
       FIG. 6  is a cross-sectional side view of an illustrative configuration that may be used for forming signal paths on housing  12 . Housing  12  may be formed from a material such as plastic, metal, carbon-fiber composite material or other fiber-based composites, or other materials. Examples in which housing  12  is formed from metal are sometimes described herein as an example. This is, however, merely illustrative. Housing  12  may be formed from any suitable material or materials, 
     As shown in  FIG. 6 , interconnect stack  64  may be formed directly on interior surface  66  of housing  12 . Interconnect stack  64  may include a lowermost layer such as a layer of polyimide or other insulator (e.g., a polymer layer) that insulates signal lines in stack  64  from housing  12  (e.g., in configurations in which housing  12  is formed from metal). Conductive layers  60  such as metal layers and insulating layers such as polymer layers  58  may be stacked in an alternating fashion on surface  66 . The uppermost layer of stack  64  (see, e.g., layer  62  of  FIG. 6 ) may be formed from an insulating material (e.g., a dielectric such as polyimide or other polymer layer) or a metal layers (e.g., aluminum, copper, gold, other metals, a metal layer formed from two or more metal sublayers and/or metal alloys, etc.). If desired, the outermost layer of stack  64  (i.e., layer  62 ) may be formed from a blanket metal layer to provide electromagnetic shielding (as an example). Metal layers  60  (sometimes referred to as metal traces) may be patterned to form signal lines and/or vias that couple signal lines in respective metal layers together. 
     Layers  58  and  60  have thicknesses (TL) that are typically significantly smaller than thickness TH of housing  12 . For example, housing walls may have a thickness on the order of 0.5-3 mm, whereas layer thickness TL for the layers in stack  64  may be 0.1-100 microns (as an example). If desired, other thickness values may be used for layers  58  and  60  (e.g., more than 10 microns or less than 10 microns as examples) and for housing  12  (e.g., more than 1 mm or less than 1 mm as examples). The use of housings thicknesses of 0.5-3 mm and interconnect stack thickness values of 0.1-100 microns is merely illustrative. 
     As shown in the cross-sectional side view of  FIG. 7 , interconnect stack  64  may include patterned metal structures that form horizontally extending signal lines  70  that are interconnected by vertically extending structures such as vias  72 . Dielectric  74  may be used to electrically isolate respective signal paths formed from structures (metal traces) such as signal lines  70  and vias  72 . 
       FIG. 8  is a diagram of equipment that may be used in forming device  10  and signal paths for device  10 . The equipment of  FIG. 8  may be used in forming device housing  12 , interconnect stack  64 , components mounted on printed circuits such as components  48  on printed circuits  46 , coupling structures that couple components  48  using metal traces in stack  64  and other signal paths in device  10 , and other electronic device structures  80 . The equipment of  FIG. 8  may include printing equipment  76 . Printing equipment  76  may include ink-jet printing equipment, pad printing equipment, screen printing equipment, and other equipment for printing blanket layers and/or patterned layers of material. Examples of structures that may be formed using equipment  76  include printed layers of dielectric, strips of dielectric, metal lines (e.g., lines formed from metallic paint or other liquid conductive material), blanket layers of metal, etc. Machining equipment  78  may be used to machine grooves and other structures into housing  12  (e.g., to form grooves in a metal housing). Global deposition equipment  84  may include equipment for depositing layers of material by blanket spray coating, by spinning, by physical vapor deposition, or other deposition techniques. Patterning equipment  86  may be used to pattern layers of material such as blanket layers of metal and/or dielectric. Equipment  86  may include photolithographic equipment such as photoresist deposition and patterning equipment, etching equipment, etc. If desired, other tools  82  may be used in processing electronic device structures  80  such as lasers for cutting grooves that penetrate partway or entirely through a housing wall or other portion of housing  12 , water jet cutting equipment, plasma cutting equipment, heating equipment, and other equipment for depositing, patterning, processing, and removing layers of dielectric and metal for structures  80 . 
     Metal signal lines on housing  12  may be used to route analog signals and/or digital signals between electrical components in device  10 . If desired, metal signal lines on housing  12  may be used to route power. In the illustrative configuration of  FIG. 9 , signals such as power supply signals are being applied to metal traces  98  and  100  in interconnect stack  64  on housing  12  from component  88 . Component  88  may be an electrical component such as a battery (as an example). Battery  88  may have a positive terminal such as terminal  90  and a ground terminal such as ground terminal  92 . Terminals  90  and  92  may be formed from springs that protrude downwards out of battery  88  to make electrical connections with respective contacts (metal traces in stack  64 ) such as contacts  98  and  100 . Contact  98  may be part of a metal trace that forms a positive power supply line in interconnect stack  64 . Contact  100  may be part of a metal trace that forms a ground power supply line in interconnect stack  64 . Dielectric layer  94  may be a polymer or inorganic layer that insulates metal housing  12  from traces  98  and  100 . If desired, ground power supply line  100  may be shorted to housing  12 . Upper dielectric layer  96  may be formed on the metal traces and underlying dielectric layers of stack  64  and may have openings to accommodate springs  90  and  92 . 
     Coupling structures such as screws and other fasteners may be used to route signals between electrical components and housing-based interconnects.  FIG. 10  shows how a fastener such as a solid screw may be used in forming a coupling structure in device  10 . As shown in the cross-sectional side view of  FIG. 10 , screw  102  may have a head such as head  104  and a shaft such as shaft  106 . Shaft  106  may have threads  108 . Shaft and head  104  may be formed from metal or other conductive material. This allows screw  102  to conduct electrical signals between housing-based interconnects and components in device  10 . 
       FIG. 11  is a cross-sectional side view of an illustrative screw that has a core surrounded by a coating. Core  110  may be formed from a conductive material such as metal (e.g., copper). Coating  112  may be formed from another conductive material such as a different metal (e.g., stainless steel, nickel, etc.). Configurations in which core  110  and coating  112  are respectively formed from a metal and a dielectric or are respectively formed from a dielectric and a metal may also be used in device  10 . 
     In the illustrative configuration of  FIG. 12 , screw  102  has been provided with a coating such as coating  116  that covers threads  108  in tip portion  114  of shaft  106 , while leaving remaining portions of shaft  106  uncovered. Head  104  and shaft  106  may be formed from metal. Coating  116  may be formed from a dielectric material to insulate tip  114  of shaft  106 . 
       FIG. 13  is a cross-sectional side view of a portion of device  10  in which an integrated circuit has been coupled to signal lines on housing  12  using coupling structures such as a pair of metal screws. As shown in  FIG. 13 , interconnect stack  64  may be formed directly on the inner surface of housing  12 . Interconnect stack  64  may include metal traces for forming signal paths such as metal traces  98  and  100 . Dielectric  94  and  96  may be used to prevent traces  98  and  100  from shorting to each other and other metal structures in device  10 . 
     Substrate  132  may be a printed circuit such as a rigid printed circuit board or a flexible printed circuit or may be another substrate that contains metal traces for conveying signals between component  120  and other components in device  10 . Component  120  may be an integrated circuit or other electrical component. Component  120  may have contacts such as illustrative metal contacts (terminals)  122 . Solder  124  may be used to mount component  120  to printed circuit  132 . In particular, solder  124  may be used to form solder joints between contacts  122  on component  120  and mating contacts  122  on the surface of printed circuit  132 . Component  120  may be a power management unit or any other electrical component. Metal traces in printed circuit  132  may be used in forming signal paths for routing signals to and from terminals  122  of component  120 . These metal traces may include vias such as vias  128  and horizontal signal lines such as signal lines  130 . 
     Screws  102 P and  102 N may serve as coupling structures that couple the signal paths of printed circuit  132  to the signal paths of interconnect stack  64  on housing  12 . Screw  102 N may be a metal screw that routes signals between a first metal line  130  on printed circuit  132  and metal trace  100  on housing  12 . The tip of the shaft of screw  102 N may be formed from bare metal that forms an electrical connection with housing (e.g., a metal housing having a threaded opening that receives the exposed metal threads of the shaft of screw  102 N). Screw  102 P may be a metal screw with an insulated tip (i.e., a shaft tip coated with insulator  116 ). The shaft of screw  102 P may be used to route signals between a second metal line  130  on printed circuit  132  and metal trace  98  on housing  12 . Because the tip of the shaft of screw  102 P is coated with dielectric, the metal of the shaft of screw  102 P does not form a short circuit to housing  12  (in this example). The shaft of screw  102 P does, however, short the second metal trace  130  in printed circuit  132  to metal trace  98  on housing  12 . With one suitable arrangement, component  120  is a power management unit, battery, or other power component. A first signal path is formed from a first contact for component  120  to first metal trace  98  in interconnect stack  64  on housing  12  through one of contacts  122 , solder joint  124 , one of contacts  126 , one of vias  128 , one of metal lines  130 , and screw  102 P. A second signal path is formed from a first contact for component  120  to second metal trace  100  in interconnect stack  64  on housing  12  through one of contacts  122 , solder joint  124 , one of contacts  126 , one of vias  128 , one of metal lines  130 , and screw  102 N. Metal line  98  may convey a positive power supply voltage or other signal on metal line  98  to other electrical components in device  10 . Metal line  100  may convey a ground power supply voltage or other signal on metal line  100  to other electrical components in device  10 . 
     In some situation, it may be desirable for a screw, other fastener, or other coupling structure in device  10  to carry more than one signal. This type of arrangement is shown in  FIG. 14 . As shown in  FIG. 14 , electrical component  120  may be mounted on printed circuit  132  using solder  124 . Component  120  may have two or more contacts, three or more contacts (as shown in  FIG. 14 ), or four or more contacts. Printed circuit  132  and screw  102  may have a corresponding number of signal paths. For example, if component  120  has three terminals that produce three separate signals, printed circuit  132  may have three corresponding signal paths for routing signals between component  120  and screw  102 , whereas screw  102  may have three corresponding signal paths for routing signals between printed circuit  132  and interconnect stack  64  on housing  12 . Interconnect stack may have three signal paths (in this example) such as signal paths  136 ,  138 , and  140 , each of which mates with a respective signal path in screw  102 . 
     Coupling structures such as screw  102  may have segmented shafts or other structures that allow the screw or other coupling structure to carry multiple signals in parallel independently. A perspective view of an illustrative screw that has two independent signal paths is shown in  FIG. 15 . As shown in  FIG. 15 , screw  102  may have a first signal path that leads between upper shaft portion  148  of shaft  106  to tip portion  142  of shaft  106  and may have a second parallel and independent path that leads between screw head  104  and side terminal  144  through a metal core. Insulating structures such as dielectric ring  146  and associated internal dielectric structures may prevent the first and second paths from becoming shorted to each other. 
     A cross-sectional side view of two-path screw  102  of  FIG. 15  taken along line  150  and viewed in direction  152  is shown in  FIG. 16 . In the example of  FIG. 16 , component  120  is mounted to printed circuit  132  with solder  124 . Component  120  has a first contact such as contact  122 P and a second contact such as contact  122 N (in this example). Metal screw  102  has two parallel signal paths. The first signal path is formed through metal head  104 , metal core  158 , which extends along longitudinal axis  162  of screw  102 , and side terminal  144 . Dielectric  146  electrically isolates the first signal path from the second signal path. The second signal path through screw  102  is formed by upper shaft portion  148 , middle shaft portion  154  (which is connected to portion  148  out of the plane of  FIG. 16 ), and lower (tip) shaft portion  142 . Tip  142  can be free of dielectric (if desired) to short tip  142  to metal housing  12  (as an example). 
     Using the two paths formed through screw  102 , a coupling structure such as screw  102  can carry electrical signals between component  120  and traces such as traces  98  and  100  in interconnect stack  64  on housing  12 . A first signal path (e.g., a positive power supply voltage path or other signal path) involves contact  122 N, solder  124 , metal traces  160  on printed circuit  132 , head  104 , shaft core  158 , terminal portion  144 , and metal trace  98 , which is in contact with terminal portion  144  of the first path. A second signal path (e.g., a ground power supply voltage path or other signal path) involves contact  122 P, solder  124 , metal traces  156  on printed circuit  132 , upper shaft portion  148 , middle shaft portion  154 , and metal trace  100 , which contacts middle portion  154  of screw  102 . The tip of screw  102  may be screwed into a threaded opening in housing  12  and may, if desired, form an additional portion of the second path (e.g., shorting portion  154  to housing  12 , which may serve as a ground). 
     If desired, a screw, other fastener, or other coupling structure may be segmented to form two parallel paths that run along the longitudinal axis of the screw or other structure. A top view of an illustrative radially segmented screw of this type is shown in  FIG. 17 . As shown in  FIG. 17 , screw  102  may have a first signal path formed from a portion of head  104  such as head portion  104 - 1  and may have a second signal path formed from a portion of head  104  such as head portion  104 - 2 . The shaft under the head may be similarly segmented. Dielectric  164  may separate portions  104 - 1  and  104 - 2  from each other and may separate the two shaft portions under head  104  from each other. Dielectric  164  and the signal paths formed from portions  104 - 1  and  104 - 2  of screw  102  may extend longitudinally along longitudinal axis  162  of screw  102  (i.e., the two parallel signal paths supported by illustrative screw  102  of  FIG. 17  may run into the page of  FIG. 17 ). In the  FIG. 17  example, the paths of screw  102  are coupled to respective signal lines  166  and  168  on dielectric layer  94  in an interconnect stack  64  formed on housing  12 . The paths of screw  102  may also be coupled to respective traces in a printed circuit, as described in connection with the paths of screw  102  of  FIG. 16 . 
     It may be desirable to use spring-loaded pins to form signal paths. Spring-loaded pins may be formed from metal structures having a body and a spring-loaded pin shaft that moves within the body. If desired, spring-loaded pins may be segmented to carry multiple parallel signals in device  10 . Consider, as an example, the scenario of  FIG. 18 . In the illustrative arrangement of  FIG. 18 , spring loaded pin  172  has body  174  and shaft (pin)  176 . Spring  186  presses shaft  176  outward away from body  174  into an opening in interconnect stack  64  on housing  12  (or an opening in a segmented screw or other coupling structure, etc.). 
     Spring loaded pin  172  in the example of  FIG. 18  has four parallel signal paths. Connections  170 , which may be formed from electrical contacts and solder joints, may be used to connect the four signal paths of pin  172  to four respective metal traces in printed circuit  132  or four conductive portions of a screw or other coupling structure. On shaft  176 , dielectric structures  184  segment shaft  176  into four respective shaft terminals  178 . Shaft terminals  178  are coupled to respective contacts  170  for spring-loaded pin  172  using signal paths in body  174 . Shaft terminals  178  mate with corresponding metal traces  180  in interconnect stack  64  (or with mating signal paths in a coupling structure, etc.). Dielectric layers  182  separate metal traces  180  and prevent the signal paths of interconnect stack  64  from being shorted to one another. In the illustrative configuration of  FIG. 18 , spring-loaded pin  172  has four terminals  178  and has four corresponding parallel signal paths coupled to connections  170 . If desired, a spring-loaded pin or other coupling structure may have a single signal path, two parallel signal paths, more than two parallel signal paths, three or more parallel signal paths, four or more parallel signal paths, etc. 
     In the illustrative configuration of  FIG. 19 , spring-loaded pin  172  has a longitudinal axis such as longitudinal axis  188 . Shaft  176  is pressed outwardly away from body  174  by a spring in body  174 . Shaft  176  has dielectric structures  184  that run parallel to axis  188  and that segment shaft  176  into four longitudinally extending terminals  178 . Each of terminals  178  can mate with a respective metal trace in interconnect stack  64  on housing  12  or other conductive paths in device  10 . 
     If desired, spring-loaded pins can form part of a coupling structure that includes a fastener such as a screw.  FIG. 20  is a top view of an illustrative screw  102  that is coupled to spring loaded-pin  172 . As shown in  FIG. 20 , screw head  104  of screw  102  has a notch such as notch  190  that receives shaft  176  of spring loaded pin  172 . Screw  102  and spring-loaded pin  176  may be formed of metal to form a signal path between interconnect stack  64  and other structures in device  10  such as printed circuit boards and components mounted to the printed circuit boards. 
     In the example of  FIG. 21 , screw head  104  has a hole such as hole  192  that passes entirely through head  192 . Shaft  176  of spring-loaded pin  172  is received within hole  192 . spring-loaded pin. If desired, shaft  176  may have multiple segments that are coupled to multiple corresponding signal paths in screw  102 . 
       FIG. 22  is a cross-sectional top view of a screw with multiple signal paths each of which is coupled to a respective spring-loaded pin  172 . As shown in  FIG. 22 , screw  102  has dielectric  196  that divides screw shaft  106  into multiple longitudinally-extending segments  194 . Each segment  194  serves as a separate signal path. Segments  194  may each have a respective notch  198  to receive a respective shaft  176  of a spring-loaded pin  172 . 
     Coupling structures for device  10  may, if desired, be formed using springs. A cross-sectional side view of an illustrative device that uses springs as coupling structures that couple together signal paths in interconnect stack  64  on housing  12  and electrical components in device  10  is shown in  FIG. 23 . As shown in  FIG. 23 , device  10  may have a display such as display  14  that includes display module  42  mounted under display cover layer  40 . Electrical components  200  may be mounted within the interior of housing  12 . Components  200  may be, for example, a battery, one or more printed circuit boards populated with integrated circuits and other electrical components, buttons, connectors, sensors, audio components, and other input-output circuitry and control circuitry. Interconnect stack  64  may be formed from layers of dielectric  58  and metal traces  60  on the inner surface of housing  12  and may, if desired, include bends that follow bends in the inner surface of housing  12  (e.g., right-angle bends or other bends). Housing  12  may have protruding portions such as portions  12 P that serve as a support structure for dielectric  58  and traces  60 . 
     Metal springs  202  may serve as coupling structures that interconnect components  200 , components such as display  14  (e.g., display module  42 ), and signal paths in interconnects  64 . Springs  202  may be formed from spring metal or other suitable metal. Solder, welds, conductive adhesive, or other mounting structures may be used to attach springs  202  to traces  60  in stack  64  on housing  12 , to metal structures such as housing  12 , to contacts on printed circuits boards or other contacts in components  200 , etc. Springs  202  may also be screwed into place with screws or mounted to device structures using other fasteners. 
       FIG. 24  is a cross-sectional side view of a portion of device  10  in which a component such as a button has been coupled to metal traces  60  on dielectric layer  58  using springs  202 . Button  204  may have a moving button member such as button member  216  that can be pressed by a user&#39;s finger from the exterior of device  10 . Button member  216  may pass through opening  214  in housing  12 . The inner surface of housing  12  may be provided with an interconnect stack formed from dielectric layers such as layer  58  and metal traces such as traces  60 . Traces  60  may be used to form signal paths that convey button signals from button  204  to control circuitry in device  10 . Springs  202  may be coupled between traces  60  and corresponding contacts  212  on button structure  206 . Button structure  206 , which may serve as a substrate for routing signals in button  204 , may contain signal paths such as signal paths  210  that are coupled between contacts  212  and terminals in a button switch such as switch  208 . When button member  216  is pressed inwardly, dome switch  208  is compressed and changes states (from open to closed or from closed to open, depending on the design of dome switch  208 ). As switch  208  is opened and closed, the resistance between lines  60  will change (e.g., the resistance will change from a high magnitude when switch  208  is open and a near zero magnitude when switch  208  is closed). Control circuitry can monitor the state of button  204  by monitoring the resistance between traces  60 . 
     In the illustrative configuration of  FIG. 24 , button  204  is coupled to housing-based interconnects using a signal path coupling structure formed from springs. If desired, a coupling structure for interconnecting a button with housing-based signal paths may be formed using a screw or other fastener. This type of arrangement is shown in  FIG. 25 . As shown in  FIG. 25 , button  204  may include button member  216 , which moves within openings  214  of housing  12  and may include a switch such as illustrative dome switch  208 , which is compressed by button member  216 . Switch  208  may be mounted on printed circuit  206 . Printed circuit  206  may contain layers of patterned metal traces such as layers  220  and layers of dielectric  222 . The traces in printed circuit  206  form signal paths that couple dome switch terminals of dome switch  208  to corresponding signal paths in screw  102 . Screw  102  may, as an example, be a two-path screw of the type described in  FIG. 16 . The paths in screw  102  may be used to couple the signal paths in printed circuit  206  to signal paths in interconnect stack  64  that are formed from dielectric layers  58  and patterned metal layers  60  on the interior surface of housing  12 . Screw  102  may be used to couple a signal path in interconnect stack  64  and/or printed circuit  206  to housing  12 , which may serve as a ground, or the tip of screw  102  can be coated with dielectric to prevent signal paths in screw  102  from being shorted to housing  12 . Spacers such as illustrative dielectric spacer  224  may be interposed between printed circuit  206  and interconnect stack  64 , if desired. 
       FIG. 26  is a cross-sectional side view of housing  12  in an illustrative configuration in which a signal path in interconnect stack  64  has been formed by placing metal trace  60  in a groove such as groove  226  in housing  12 . Groove  226  may be machined in housing  12  using a machining tool (e.g., a milling bit), may be cut using a laser, or may be formed using other techniques. Housing  12  may be a metal housing or a housing formed from other material. Dielectric layer  58  may be interposed between trace  60  and housing  12  to prevent trace  60  from being shorted to housing  12 . Additional layers of dielectric  58  may be formed over traces such as trace  60 . There is one trace in groove  226 , but, if desired, groove  226  may contain multiple parallel traces and/or multiple grooves  226  may be formed in housing  12  to form housing-based signal paths for device  10 . 
     If desired, signal paths may be formed in sidewall portions of housing  12 , as shown by illustrative metal trace  60  in groove  226  in housing sidewall  12 ′ in housing  12 . Dielectric layer  58  may be used to prevent metal trace  60  from being shorted to metal housing  12 . Coupling structure  228  may be used to couple trace  60  to metal traces in printed circuit  230  such as metal trace  232 . Coupling structure  228  may be, for example, a spring loaded pin that contacts trace  60  through an opening in sidewall  12 ′. 
     If desired, multiple housing-based signal paths may be formed in a groove in housing sidewall  12 ′. As shown in  FIG. 28 , signal path  60 B may be formed at a first vertical location in sidewall  12 ′ and may be coupled to a printed circuit or other structure using a first spring-loaded pin  228 B or other coupling structure. Parallel signal path  60 A may be formed at a second vertical location in sidewall  12 ′ and may be coupled to the printed circuit or other structure using a second spring-loaded pin  228 A or other coupling structure.  FIG. 29  is a cross-sectional side view showing how coupling structures such as spring-loaded pins  228 A and  228 B of  FIG. 29  may be coupled to respective traces  232 A and  232 B in printed circuit  230 . 
     As shown in the illustrative configuration of  FIG. 30 , coupling structures such as spring-loaded pins  228  may be coupled to metal trace(s)  60  at multiple distinct horizontal locations along housing sidewall  12 ′. There may be a separate signal path coupled to each pin  228  of  FIG. 30 , multiple pins  228  may be coupled to a common metal trace on housing  12 ′, or other signal path configurations may be used in interconnecting the housing-based signal paths formed from metal trace(s)  60  to coupling structures such as pins  228  of  FIG. 30 . 
     If desired, coupling structures such as washers, standoffs, or other structures may be used in coupling housing-based signal paths on housing  12  to signal paths in a printed circuit or other structure in device  10 . Consider, as an example, the arrangement of  FIG. 31 . As shown in the illustrative cross-sectional side view of housing  12  of  FIG. 31 , device  10  may have housing-based signal paths formed from interconnect stack  64  on the interior surface of housing  12 . Interconnect stack  64  may contain signal paths formed from separate metal traces  60 A and  60 B on dielectric layer  58 . Coupling structure  240  may be segmented into two halves  242 A and  242 B separated by dielectric  244  and running along longitudinal axis  246 . Coupling structure may be a ring-shaped washer with an central opening, may be a threaded standoff in housing  12 , may be a threaded nut, or may have other configurations. 
     The center of structure  240  may have an opening that receives screw  102 . Screw  102  may be electrically insulated from washer  240 , housing  12 , and the signal paths in printed circuit  248  (as an example). Printed circuit  248  may have signal paths formed using metal traces such as metal traces  250 A and  250 B. Electrical components may be mounted on printed circuit  248  or may otherwise be connected to the signal paths on printed circuit  248 . With this configuration, signal path  250 A on printed circuit  248  is coupled to signal path  60 A on housing  12  using segment  242 A of structure  240  and, in parallel, signal path  250 B on printed circuit  248  is coupled to signal path  60 B on housing  12  using segment  242 B of structure  240 . Dielectric  244  ensures that these two parallel signal paths are not shorted to each other. If desired, coupling structure  240  may contain three or more parallel signal paths. The configuration of  FIG. 31  in which structure  240  has two parallel signal paths is merely illustrative. 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20140214
Publication Date: 20160927
Grant Date: 20160927
Priority Date: 20140214
Inventors: LOR JASON
NANGIA SIDDHARTH
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F1/182", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/16", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/16", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/182", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 53799411