Patent Application
20180375239
Various types of connectors may be used to connect electronic components in a device.
Examples are disclosed that relate to a connector for connecting a liquid metal circuit element to a solid conductor. One example provides a connector including a body defining a channel configured to contain a liquid metal, the body being configured to interface mechanically with the liquid metal circuit element. The connector also comprises a conductive path disposed within the channel and exposed to an interior of the channel to form a first electrical interface configured to interface with the liquid metal circuit element, the conductive path also comprising a second electrical interface.
Another example provides a connector system for connecting to a plurality of liquid metal circuit elements, the connector system comprising a plurality of integrated connectors, each connector comprising a body defining a channel configured to contain a liquid metal, the body being configured to interface mechanically with a liquid metal circuit element and incorporating a conductive path between a first electrical interface located at an interior surface of the channel and a second electrical interface.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure.
Liquid metal circuit elements may be incorporated into a variety of devices, for example, to provide electrical pathways between device components. As a more specific example, some electronic devices may include hinges, joints, fabric components, and other regions configured to flex between electronic components. In such regions, a liquid metal circuit element may be utilized to electrically connect the device components and maintain a conductive path as the device components are bent and/or rotated relative to one another. In contrast, a solid conductor, such as a copper trace or wire, may fatigue and/or break after a number of bend cycles.
A liquid metal circuit element may take the form of a liquid conductor such as eutectic gallium-indium (EGaIn) or other suitable gallium-containing material, formed on and/or encapsulated in a flexible material, such as polyimide and/or polydimethylsiloxane. In some examples, the liquid metal circuit element may take the form of a liquid metal disposed over a solid conductive trace as a self-healing component, or a liquid metal contained within a microfluidic conduit. In either case, the use of a liquid metal circuit element may help avoid circuit breakage from repeated flexing compared to connections that use only solid metal traces.
However, electrically connecting a solid conductor to a liquid metal circuit element may present challenges. For example, where a wire is inserted through an encapsulant layer (e.g. of a liquid metal-containing microfluidic conduit) to interface with a liquid metal, repeated flexing of the microfluidic conduit may cause the wire to detach, resulting in a loss of electrical conductivity.
Accordingly, examples are disclosed that relate to connecting a liquid metal circuit element to a solid conductor that may help to avoid such problems. In one example, a connector may be formed by insert molding a body defining a channel incorporating one or more conductive elements, such that the one or more conductive elements are contained at least partially within the body and exposed to an interior surface of the channel to form a first interface. The conductive element(s) may alternatively or additionally be incorporated by deposition on an interior surface of the channel after forming the body of the connector. The connector also includes a second interface configured to be connected to a solid conductor. When connected to a liquid metal circuit element and a solid conductor, liquid metal from the liquid metal circuit element enters the channel and contacts the conductive element, thereby forming a conductive path between the solid conductor and the liquid conductor. The molding of the conductive elements in the body may provide for a robust connection to a solid circuit element, and the channel may be configured to form a tight seal with the liquid metal circuit element, thereby helping to avoid problems such as detachment, leakage, and weakness described above.
Prior to discussing these examples,
The keyboard unit 104 and the connector positioned therein bend around a bottom corner of the display to a front of the display 102 in a first flex region 108a. As illustrated, the bend in this region is relatively sharp, conforming closely to the corner of the computing system 100. The keyboard unit 104 continues up the front surface of the display, and bends sharply down and away from the front surface of the display in a second flex region 108b. The bend in this region is also sharp.
As the keyboard unit 104 potentially may be moved between the “open” and “closed” positions, as well as other possible positions, multiple times a day for years of use, the flex regions 108a-b may flex a very large number of times during the device lifetime. Thus, a liquid metal circuit element may be used to help prevent loss of conductivity in the flex regions 108a-b in an event that a solid conductor in a trace and/or wire may break.
The connector system 200 may be formed in any suitable manner, such as via insert molding. In such a process, the plurality of conductive elements 212 for the channel 210 of each connector 202 may be placed in a corresponding location in a mold, and the mold may be filled with a moldable material (e.g. a thermoplastic material). The moldable material may then be hardened to incorporate the plurality of conductive elements with the body 208 of each connector 202. In other examples, the connector system 200 may be formed via a casting process, via 3-d printing, or in any other suitable method. The connector system 200 may be formed from any suitable electrically insulating material. In the specific example of a connector system formed by insert molding, example materials include, but are not limited to, polycarbonate, nylon, PET, ABS, and other thermoplastic materials.
Likewise, in some examples, the plurality of conductive elements 212 may be deposited on an interior surface of the channel 210 after molding, rather than being incorporated while forming the body 208 defining the channel 210. For example, conductive elements 212 may be formed by printing, deposition (e.g. physical vapor deposition), or other suitable method.
The conductive elements 212 may comprise any suitable structure. In some examples, the conductive elements comprise filaments arranged in a mesh structure, as shown in magnified view 206. A mesh structure may be securely coupled within the body 208 of a channel 210 by insert molding, and thus be resistant to being pulled or knocked out of the body 208. Further, a mesh structure that is at least partially exposed to an interior of the channel may present a relatively large surface area for electrically interfacing with the liquid metal conductor. As another example,
Connector 300 may be configured as a stand-alone structure for connecting to a single liquid metal circuit element, or may be one of a plurality of connectors integrated in an electrically parallel arrangement. Likewise, in some examples, a single connector comprising a conductive mesh may be used as a stand-alone structure. Connector 300 comprises a body 306 defining a channel 304. The channel 304 may be a microfluidic channel having a diameter of tens to hundreds of micrometers and an interior surface configured to interface a liquid metal circuit element. Body 306 may be manufactured in any suitable manner. Examples include, but are not limited to, molding, casting, and additive manufacturing (3-d printing).
Each connector 202 may comprise any suitable configuration to connect to a liquid metal conduit. In some examples, the connector 202 may be configured as a male part to be fit within an interior of a corresponding liquid metal conduit. In such an example, an exterior surface of the channel may comprise a roughened texture or detent features configured to increase friction between the channel and conduit and thus reduce likelihood of the channel and conduit becoming disconnected. In other examples, a channel may be configured as a female end of an electrical connector, and thus conform around an exterior of a liquid metal conduit comprising a complementary male configuration. In connector systems comprising a female-configured connector, for each connector, an interior surface of a female-configured channel may be roughened or include detent features to achieve a similar fit.
In some examples, after insertion, the joint between the connector system 200 and liquid metal circuit element 204 may be sealed to help secure the connection. The connection may be sealed in any suitable manner. Examples include, but are not limited to, adhesives, polymer films (e.g. a layer of polydimethylsiloxane), and welding (e.g. where compatible thermoplastic materials are used to form the liquid metal circuit element and the connector system).
The conductive elements within each channel may be formed from any suitable material. In some examples, the conductive elements may be formed from a metal such as copper, gold, silver, aluminum, and alloys thereof. In other examples, the conductive elements may be formed from other conductive compounds, elements or composites. For example, the conductive elements may be formed from or coated with a conductive material configured to be wetted well by the liquid metal conductor. Such materials may include materials coated with conductors having a surface energy tuned to match or integrate with the liquid metal conductor. Examples include, but are not limited to, graphene coated fibers, silver coated fibers, silver coated textiles, silver nanowire coated surfaces, sputtered conductive surfaces, and other metallic fibers.
Likewise, any suitable liquid metal material may be used. Suitable liquid metal materials include liquid metals that are liquid at an intended operating temperature of a device. Examples include gallium, eutectic gallium/indium (eGaIn), eutectic gallium/indium/tin (Galinstan), and other gallium alloys.
As mentioned above, each connector 206 of connector system 200 may include a second interface to electrically interface with a solid conductor. In
As shown, each connector 202 is configured to “plug” into a complementary conduit 410 of a liquid metal circuit element 414 at a corresponding microfluidic inlet 412, thereby allowing a secure connection between liquid and solid circuit elements to be quickly formed. Liquid metal may be added to conduits 410 after connecting the connector system 200 to the liquid metal circuit element 414, for example, via vacuum filling, syringe injection, or in any other suitable manner. Liquid metal within each conduit 410 forms an electrical connection with conductive elements in the channel of each connector. A second electrical interface between each connector and each corresponding trace completes the electrical path between liquid metal circuit element 414 and circuit board 402.
It is to be understood that the connector and connector systems illustrated in
The example connectors disclosed herein may be used in any suitable electronic device.
Another example provides a connector for a liquid metal circuit element, the connector comprising a body defining a channel configured to contain a liquid metal, the body being configured to interface mechanically with the liquid metal circuit element, and a conductive path comprising a plurality of conductive elements disposed within the channel and exposed to an interior of the channel to form a first electrical interface configured to interface with the liquid metal circuit element, and the conductive path also comprising a second electrical interface. In such an example, the plurality of conductive elements may be additionally or alternatively formed at least partially from a metal. In such an example or any preceding example, the plurality of conductive elements may additionally or alternatively comprise a mesh structure. In such an example or any preceding example, the body may additionally or alternatively be formed from a polymer material. In such an example or any preceding example, the body may additionally or alternatively be formed at least partially from a conductive polymer. In such an example or any preceding example, the conductive path may additionally or alternatively be at least partially incorporated into the body. In such an example or any preceding example, the body defining the channel may additionally or alternatively be configured as a male end of a mechanical connector. Such an example or any preceding example may additionally or alternatively further comprise a liquid metal positioned within the channel. In such an example or any preceding example, the second electrical interface may additionally or alternatively be configured to connect to one or more of a wire and a trace. In such an example or any preceding example, the connector may additionally or alternatively be integrated with a plurality of other connectors.
Another example provides a connector system comprising an integrated plurality of connectors, each connector comprising a body defining a channel configured to contain a liquid metal, the body being configured to interface mechanically with a liquid metal circuit element and incorporating a conductive path between a first electrical interface located at an interior surface of the channel and a second electrical interface. In such an example or any preceding example, the conductive path may additionally or alternatively further comprise one or more conductive elements contained at least partially within the body and exposed to an interior of the channel, the one or more conductive elements each being configured to interface with the liquid metal circuit element to form a first electrical interface. In such an example or any preceding example, the one or more conductive elements may be additionally or alternatively arranged in a mesh structure. In such an example or any preceding example, each of the one or more conductive elements may additionally or alternatively comprise a metal. Such an example or any preceding example may additionally or alternatively further comprise a liquid metal positioned within the channel.
Another example provides an electronic device comprising a plurality of connectors for connecting to a plurality of liquid metal circuit elements, the electronic device comprising a plurality of integrated liquid metal circuit elements, a connector system comprising an integrated plurality of connectors, each connector being connected to one of the plurality of integrated liquid metal circuit elements and each connector comprising a body defining a channel, the channel configured to contain a liquid metal circuit element, and a conductive path at least partially incorporated into the body, the conductive path comprising one or more conductive elements contained at least partially within the body and exposed to an interior of the channel to form a first electrical interface configured to interface with the liquid metal circuit element, and the conductive path also comprising a second electrical interface. Such an example or any preceding example may additionally or alternatively further comprise a liquid metal positioned within the channel. In such an example or any preceding example, the one or more conductive elements may each additionally or alternatively comprise a mesh structure. In such an example or any preceding example, the second electrical interface may additionally or alternatively be connected to one or more of a wire and a trace. In such an example or any preceding example, the body defining a channel may additionally or alternatively be configured as a male end of a mechanical connector.
It will be understood that the configurations and/or approaches described herein are exemplary in nature, and that these specific embodiments or examples are not to be considered in a limiting sense, because numerous variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. As such, various acts illustrated and/or described may be performed in the sequence illustrated and/or described, in other sequences, in parallel, or omitted. Likewise, the order of the above-described processes may be changed.
The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems and configurations, and other features, functions, acts, and/or properties disclosed herein, as well as any and all equivalents thereof.
