Patent Grant
11201426
The number of types of electronic devices that are commercially available has increased tremendously the past few years and the rate of introduction of new devices shows no signs of abating. Devices such as tablets, laptops, netbooks, desktops, all-in-one computers, smart phones, storage devices, portable media players, wearable computing devices, navigation systems, monitors, and others, have become ubiquitous.
These electronic devices often include one or more connector receptacles through which they can provide and receive power and data. Power and data can be conveyed over cables that include a connector insert at each end of a cable. The connector inserts can be inserted into receptacles in the communicating electronic devices. In other electronic systems, contacts on a surface of first device can be in direct contact with contacts on a second device without the need for an intervening cable.
Contacts on a surface of an electronic device can be positioned in a highly visible location. As such, their appearance can be a reflection of the quality and care with which the electronic device has been made. Located where they are, these contacts can further be susceptible to exposure to liquids or other substances that can cause corrosion or discoloration. Contacts at a surface of a device can further be subject to scratches and other types of marring.
Some of these electronic devices can be very popular and can be manufactured in great numbers. Therefore it can be desirable that these contacts be readily manufactured such that demand for the electronic devices can be met. It can also be desirable to reduce the consumption of rare or precious materials used in their manufacturing.
Thus, what is needed are electrical contacts and their methods of manufacture, where the electrical contacts have a desired appearance as well as a low contact resistance. It can also be desirable that these contacts have good corrosion protection and scratch resistance, and be readily manufactured while consuming a reduced amount of rare or precious materials.
Accordingly, embodiments of the present invention can provide electrical contacts and their methods of manufacture, where the electrical contacts have a desired appearance as well as a low contact resistance. These contacts can have good corrosion protection and scratch resistance, and can be readily manufactured while consuming a reduced amount of rare or precious materials. These contacts can be located at a surface of an electronic device, at a surface of a connector insert, in a connector insert on a cable, in a connector receptacle on an electronic device, or elsewhere in a connector system.
Contacts on a surface of a device can be in highly visible location. As such, embodiments of the present invention can provide methods of coating the contacts to have a specific color. The color can be selected to match a color of a portion of a device enclosure for the electronic device housing the contacts. For example, the color of the contacts can be chosen to match a portion of the device enclosure that surrounds or is near the contacts. This can provide an electronic device where the contacts and at least a portion of the device enclosure appear to be made of the same material. This uniform appearance can enhance the perceived quality and value of the electronic device.
These and other embodiments of the present invention can instead provide methods of coating contacts to provide a color to contrast with a color of a portion of a device enclosure for the electronic device housing the contacts. This color can be a noticeable color that allows a user to quickly find the contacts for mating with contacts of a second or accessory device. This contrasting color can also be chosen to imply a manufacturing source, or to match other electronic devices, such as a second or accessory device.
In these and other embodiments of the present invention, the contacts can have a specific finish, such as a matte or gloss finish. The color can also have a level of transparency. The contacts can also have more than one color. For example, a logo or other fanciful, identifying, or other information can be conveyed by more than one color on a contact.
These and other embodiments of the present invention can provide electrical contacts having a low contact resistance. For example, these contacts can have a textured surface having patterns of raised areas or ridges. These raised areas or ridges can provide a large number of contacting points between the contacts and corresponding contacts on a second or accessory device when the contacts are mated with the corresponding contacts.
These and other embodiments of the present invention can provide electrical contacts having good corrosion and scratch resistance. For example, a coating to provide color can be placed over a surface of the contact and this additional coating can provide an amount of protection for the contact against corrosion or scratches.
These and other embodiments of the present invention can provide contacts having a layer of a silicon based polymer. The silicon based polymer can be dyed to have a specific color, for example a color to match or contrast with at least a portion of an electronic device housing the contacts. Unfortunately, a silicon-based polymer can be a poor conductor. Accordingly, embodiments of the present invention can use this coating only over a portion of a surface of a contact, while the remainder of the surface of the contact can be used to form electrical connections with corresponding contacts on corresponding connectors or devices. In these and other embodiments of the present invention, instead of a silicon-based polymer, a germanium-based polymer can be used.
More specifically, in these and other embodiments of the present invention, a plurality of holes can be formed in at least a portion a surface of a contact. These holes can leave a pattern of raised areas or ridges on the surface of the contact. One or more layers can be plated or otherwise formed on at least a portion of the surface of the contact. A layer of silicon-based polymer can be applied as a gel to at least a portion of the surface of the contact. A solvent can then optionally be sprayed or otherwise applied to the gel. The silicon based polymer can be cured such that it contracts into the holes leaving the raised areas or ridges exposed. The optional solvent can help to remove water from the gel during curing to avoid cracking. The exposed areas or ridges can form electrical pathways with a corresponding contact on a corresponding connector or device when the contact and the corresponding contact are mated.
In these and other embodiments of the present invention, the holes can be formed in various ways. A substrate of the contact can be formed of copper, copper alloy, or other material. The holes in a surface of a contact can be formed by sandblasting, chemical etching, photolithography, laser etching, stamping, coining, 3-D printing, metal-injection molding, printing, casting, or they can be formed in other ways. To avoid the appearance of lines or other artifacts in the pattern of holes, such as light or dark patches, the location of the holes can be varied or randomized. For example, a laser can have a portion of its position information for some or all of the holes varied or randomized in order to disperse straight lines or other regular or repeating patterns that might otherwise be visible. In these and other embodiments of the present invention, in order to avoid the appearance of lines, light or dark patches, or other artifacts, the depths of the holes can be varied or randomized. In these and other embodiments of the present invention, the diameter of the holes can be varied or randomized. Also, holes can be omitted from areas or regions on contacts where such holes can interfere with the assembly or operation of the contacts. For example, where contacts are located in an injection molded housing, holes can be omitted from areas or regions that are under or near the injection molded housing.
In these and other embodiments of the present invention, the holes can have various sizes and spacings. For example, the diameter of the holes can be less than 20 microns, 20-40 microns, 40 microns, 42 microns, 40-45 microns, 45 microns, 48 microns, 55 microns, 52-58 microns, or more than 60 microns. The holes can have a depth of less than 5 microns, 5-10 microns, 8 microns, 10 microns, 10-30 microns, 12 microns, 13 microns, 15 microns, 20 microns, 20-25 microns, or more than 25 microns. The holes can have a center-to-center pitch of less than 20 microns, 20-50 microns, 40 microns, 50 microns, 30-60 microns, 50 microns, 60 microns, 70 microns, 50-70 microns, or more than 70 microns. The holes can have a spacing of less than 5 microns, 5-10 microns, 10 microns, 20 microns, 10-20 microns, 15 microns, 20 microns, 25 microns, 15-25 microns, or more than 25 microns. The spacing or center-to-center pitch of the holes can be varied or randomized to avoid visible patterns formed by the holes. For example, the X and Y coordinates of the holes can be varied in a range such as a plus or minus 3, 4, 5, or more than 5 micron range. These values can be stored in a table and used to modify target information for a laser forming the holes. Light and dark spots can be reduced or removed by adjusting values in the table.
After the holes have been formed, one or more plating layers can be applied to the surface of the contact. For example, a top plate can be formed over the contact to provide corrosion and scratch protection. This top plate can be formed of rhodium-ruthenium or other material. A barrier layer can be formed over the contact before the top plate is formed to prevent discoloration of the top plate by the copper substrate. The barrier layer can be tin-copper, nickel, palladium, silver, tin-copper-nickel, copper-nickel, tin-nickel, nickel-tungsten, electroless nickel, or other material. One or more adhesion layers can be applied before or after the barrier layer, or both. These adhesion layers can be a gold flash or other layer. Other layers can also be included. For example, a layer of nickel-tungsten alloy, tin-nickel, electroless nickel, copper-nickel, silver, or other material can be plated or formed over the substrate before the barrier layer. Other combinations, such as a top plate of rhodium-ruthenium over silver, palladium, nickel, electroless nickel, a nickel-tungsten alloy, tin-nickel, tin-copper, tin-copper-nickel, copper-nickel, tin-nickel, nickel-tungsten, or other nickel alloy can be used, where one or more gold layers can be included. Layers of gold over nickel can also be used in these and other embodiments of the present invention. Additional steps, such as electro-polishing or copper plating can be performed on the substrate after the holes have been formed and before further plating to smooth areas damaged by the laser. In these and other embodiments of the present invention, these layers can be formed by sputtering, vapor deposition, electroplating, or other method. In these and other embodiments of the present invention, the order of these steps can be varied. For example, a substrate can be plated before holes are formed.
A dyed silicon-based polymer can then be applied as a gelatinous or viscous solution to one or more surfaces of the contact. The dyed silicon-based polymer can be a sol-gel, formed using a sol-gel process such as the Stöber process. In these and other embodiments of the present invention, tetraethyl orthosilicate (TEOS) can be hydrolyzed to form a silicon oxide network, which can be more generally referred to as sol-gel. In these and other embodiments of the present invention, instead of hydrolyzing, a similar process using a solvent can be employed. The sol-gel can be dyed and applied to one or more surfaces of the contact. A solvent can be applied to the sol-gel. In these and other embodiments of the present invention, both the sol-gel and the solvent can be applied by spraying, printing, or other method. After the sol-gel and optional solvent have been applied, the result can be cured. After curing, the sol-gel can contract to fill the holes, again leaving the surrounding raised portions and ridges exposed. These surrounding raised portions and ridges can then form an electrical connection with a corresponding contact when the contact and the corresponding contact are mated.
The sol-gel coated contacts can be cured or dried at room or a higher temperature. The die particles in the sol-gel can begin to aggregate as the sol-gel is cured or dried. As the curing process continues, the sol-gel can become more gelatinous and the aggregations of dyed particles can begin to themselves aggregate. The sol-gel can then become a solid as it contracts into the holes and pulls back from the raised portions and ridges. The optional solvent can help to prevent cracking and other damage to the sol-gel by removing water from the sol-gel during curing. The dried sol-gel can consume as little as eight percent of the original volume of the sol-gel.
In these and other embodiments of the present invention, instead of using a sol-gel, other materials, such as conductive ink or other types of ink can be used. In these and other embodiments of the present invention, paint can be used. For example, a polymeric paint, such as a polytetrafluoroethylene (PTFE) based paint, can be used. These inks or paints can be applied using pad printing, ink-jet printing, 3-D printing, aerosol jet printing, or other types of printing. In these and other embodiments of the present invention, the formation of holes can be optional.
While embodiments of the present invention are well-suited to electrical contacts and their method of manufacturing, these and other embodiments of the present invention can be used to improve the appearance and corrosion resistance of other structures. For example, electronic device cases and enclosures, connector housings and shielding, battery terminals, magnetic elements, measurement and medical devices, sensors, fasteners, various portions of wearable computing devices such as clips and bands, bearings, gears, chains, tools, or portions of any of these, can be covered with coatings, plating, and other layers as described herein and otherwise provided for by embodiments of the present invention. The coatings, plating, and other layers for these other structures can be formed or manufactured as described herein and otherwise provided for by embodiments of the present invention. For example, magnets and other structures for fasteners, connectors, speakers, receiver magnets, receiver magnet assemblies, microphones, and other devices can be improved by structures and methods such as those shown herein and in other embodiments of the present invention.
In various embodiments of the present invention, the contacts and their connector assemblies can be formed in various ways of various materials. For example, contacts and other conductive portions can be formed by stamping, coining, metal-injection molding, machining, micro-machining, 3-D printing, or other manufacturing process. The conductive portions can be formed of stainless steel, steel, copper, copper alloy, copper titanium, phosphor bronze, palladium, palladium silver, or other material or combination of materials, as described herein. They can be plated or coated with nickel, gold, palladium, rhodium, ruthenium, or other material, as described herein. The nonconductive portions can be formed using injection or other molding, 3-D printing, machining, or other manufacturing process. The nonconductive portions can be formed of silicon or silicone, Mylar, Mylar tape, rubber, hard rubber, plastic, nylon, elastomers, liquid-crystal polymers (LCPs), ceramics, or other nonconductive material or combination of materials.
Embodiments of the present invention can provide contacts and their connector assemblies that can be located in, or can connect to, various types of devices, such as portable computing devices, tablet computers, desktop computers, laptops, all-in-one computers, wearable computing devices, cell phones, smart phones, media phones, storage devices, keyboards, covers, cases, portable media players, navigation systems, monitors, power supplies, adapters, remote control devices, chargers, and other devices. These contacts and their connector assemblies can provide pathways for signals that are compliant with various standards such as Universal Serial Bus (USB), High-Definition Multimedia Interface® (HDMI), Digital Visual Interface (DVI), Ethernet, DisplayPort, Thunderbolt™, Lightning®, Joint Test Action Group (JTAG), test-access-port (TAP), Directed Automated Random Testing (DART), universal asynchronous receiver/transmitters (UARTs), clock signals, power signals, and other types of standard, non-standard, and proprietary interfaces and combinations thereof that have been developed, are being developed, or will be developed in the future. In various embodiments of the present invention, these interconnect paths provided by these contacts can be used to convey power, ground, signals, test points, and other voltage, current, data, or other information.
Various embodiments of the present invention can incorporate one or more of these and the other features described herein. A better understanding of the nature and advantages of the present invention can be gained by reference to the following detailed description and the accompanying drawings.
In this example, host device 110 can be connected to accessory device 120 in order to share data, power, or both. Specifically, electrical contacts (or more simply, contacts) 112 on host device 110 can be electrically connected to contacts 122 on accessory device 120. Contacts 112 on host device 110 can be electrically connected to contacts 122 on accessory device 120 via cable 130. In other embodiments of the present invention, contacts 112 on host device 110 can be in physical contact and directly and electrically connected to contacts 122 on accessory device 120. In still other embodiments of the present invention, one or more optical contacts (not shown) supporting one or more optical connections between host device 110 and accessory device 120 can be included with contacts 112 and 122.
To facilitate a direct connection between contacts 112 on host device 110 and contacts 122 on accessory device 120, contacts 112 on host device 110 and contacts 122 on accessory device 120 can be located on the surfaces of their respective devices. But this location can make them highly visible to users, as well as vulnerable to exposure to liquids, fluids, or other types of contaminants. This location can also make the contacts vulnerable to scratches, marring, or other damage.
Accordingly, embodiments of the present invention can provide methods of coating contacts to provide a specific color. The color can be selected to match a color of a portion of a device enclosure for the electronic device housing the contacts. For example, the color of the contacts can be chosen to match a portion of the device enclosure that surrounds or is near the contacts. This can provide an electronic device where the contacts and at least a portion of the device enclosure appear to be made of the same material. This uniform appearance can enhance the perceived quality and value of the electronic device.
These and other embodiments of the present invention can instead provide methods of coating contacts to provide a color to contrast with a color of a portion of a device enclosure for the electronic device housing the contacts. This color can be a noticeable color that allows a user to find the contacts quickly for mating with contacts of a second or accessory device. This contrasting color can also be chosen to imply a manufacturing source, or to match other electronic devices, such as a second or accessory device.
In these and other embodiments of the present invention, the contacts can have a specific finish, such as a matte or gloss finish. The color can also have a level of transparency. The contacts can also have more than one color. for example, a logo or other fanciful, identifying, or other information can be conveyed by more than one color on a contact.
These and other embodiments of the present invention can provide electrical contacts having a low contact resistance. For example, these contacts can have a textured surface having patterns of raised areas or ridges. These raised areas or ridges can provide a large number of contacting points between the contacts and corresponding contacts on a second or accessory device when the contacts are mated with the corresponding contacts.
These and other embodiments of the present invention can provide electrical contacts having good corrosion and scratch resistance. For example, a coating to provide color can be placed over a surface of the contact and this additional coating can provide an amount of protection for the contact against corrosion or scratches. Examples are shown in the following figures.
In these and other embodiments of the present invention, the holes can have various sizes or diameters 280 and spacings 282. For example, the diameter 280 of holes 210 can be less than 20 microns, 20-40 microns, 40 microns, 42 microns, 40-45 microns, 45 microns, 48 microns, 55 microns, 52-58 microns, or more than 60 microns. Holes 210 can have a depth 284 of less than 5 microns, 5-10 microns, 8 microns, 10 microns, 10-30 microns, 12 microns, 13 microns, 15 microns, 20 microns, 20-25 microns, or more than 25 microns. Holes 210 can have a center-to-center pitch 286 of less than 20 microns, 20-50 microns, 40 microns, 50 microns, 30-60 microns, 50 microns, 60 microns, 70 microns, 50-70 microns, or more than 70 microns. Holes 210 can have a spacing 282 of less than 5 microns, 5-10 microns, 10 microns, 20 microns, 10-20 microns, 15 microns, 20 microns, 25 microns, 15-25 microns, or more than 25 microns. The spacing 282 or center-to-center pitch 286 of holes 210 can be varied or randomized to avoid visible patterns formed by the holes. For example, the X and Y coordinates of holes 210 can be varied in a range such as a plus or minus 3, 4, 5, or more than 5 micron range. These values can be stored in a table and used to vary a target for a laser forming the holes. Light and dark spots can be reduced or removed by adjusting values in the table.
In
In
In
In these and other embodiments of the present invention, instead of using a sol-gel, other materials, such as conductive ink or other types of ink can be used. In these and other embodiments of the present invention, paint can be used. For example, a polymeric paint, such as a polytetrafluoroethylene (PTFE) based paint, can be used. These inks or paints can be applied using pad printing, ink-jet printing, 3-D printing, aerosol jet printing, or other types of printing. In these and other embodiments of the present invention, the formation of holes 210 can be optional.
Accordingly, in
In these and other embodiments of the present invention, the holes can be positioned using other methods or algorithms. For example, the holes can be arranged in a honeycomb pattern, a randomized honeycomb pattern, or other honeycomb-based pattern. A randomized honeycomb pattern can be formed by starting with a honeycomb pattern and then moving each hole a randomized amount, as was done with the holes in
The angle at which a laser, drill, or other tool forms the holes can be varied as the holes are formed. Alternatively, more than one laser can be used to form the holes, where the more than one laser are positioned at different angles relative to the contact surface. This can further reduce any observable patterns of lines, curves, or light or dark areas.
In these and other embodiments of the present invention, the holes can be positioned in a spiral pattern where the holes are arranged to provide maximum spacing. For example, the holes can be arranged in a cyclotron spiral with a constant divergence angle between successive holes. These holes can be arranged in a pattern based on a logarithmic spiral, such as a golden spiral. The holes can be arranged in an approximation of the golden spiral, such as a Fibonacci spiral. Such a spiral can be approximated with Vogel's model using the equations
radius=c(sqrt(n))
and
theta=n(137.508)
where the radius and the angle theta define the placement of hole n, c is a constant, and 137.508 degrees is approximately equal to the golden angle. A pattern of holes generated using this method is shown in
To further reduce reflections from raised portions and ridges 500 (shown in
To still further reduce reflections from raised portions and ridges 500, holes 210 can be filled with dyed silicon-based polymer 400 to a specific level. For example, a ratio between a depth of a hole 210 and a depth of dyed silicon-based polymer 400 in the hole can be adjusted to be between 1.1 and 1.4, between 1.1 and 1.5, between 1.1 and 1.6, or it can be adjusted to be in another range of values.
In
In these and other embodiments of the present invention, holes 210 can be arranged to provide a texture for contacts 112 that can match or be similar to a texture of a surrounding device enclosure 1310, as shown in
While embodiments of the present invention are well-suited to electrical contacts and their method of manufacturing, these and other embodiments of the present invention can be used to improve the appearance and corrosion resistance of other structures. For example, electronic device cases and enclosures, connector housings and shielding, battery terminals, magnetic elements, measurement and medical devices, sensors, fasteners, various portions of wearable computing devices such as clips and bands, bearings, gears, chains, tools, or portions of any of these, can be covered with coatings, plating, and other layers as described herein and otherwise provided for by embodiments of the present invention. The coatings, plating, and other layers for these other structures can be formed or manufactured as described herein and otherwise provided for by embodiments of the present invention. For example, magnets and other structures for fasteners, connectors, speakers, receiver magnets, receiver magnet assemblies, microphones, and other devices can be improved by structures and methods such as those shown herein and in other embodiments of the present invention. These and other embodiments of the present invention can also be used to improve the adhesion of structures. For example, a plurality of holes can be formed in a surface of an object as outlined herein. A nickel or other corrosion layer can be formed on the surface. An adhesive layer can then be applied to the surface. The holes can assist the surface to adhere to a second surface.
In these and other embodiments of the present invention, including the above contacts, other layers, such as barrier layers to prevent corrosion of internal structures can be included. For example, barrier layers, such as zinc barrier layers, can be used to protect magnets or other internal structures from corrosion by cladding or plating layers. Catalyst layers can be used to improve the rate of deposition for other layers, thereby improving the manufacturing process. These catalyst layers can be formed of palladium or other material. Stress separation layers, such as those formed of copper, can also be included in these and other embodiments of the present invention, including the above contacts. Other scratch protection, passivation, and corrosion resistance layers can also be included.
In various embodiments of the present invention, the contacts and their connector assemblies can be formed in various ways of various materials. For example, contacts and other conductive portions can be formed by stamping, coining, metal-injection molding, machining, micro-machining, 3-D printing, or other manufacturing process. The conductive portions can be formed of stainless steel, steel, copper, copper alloy, copper titanium, phosphor bronze, palladium, palladium silver, or other material or combination of materials, as described herein. They can be plated or coated with nickel, gold, palladium, rhodium, ruthenium, or other material, as described herein. The nonconductive portions can be formed using injection or other molding, 3-D printing, machining, or other manufacturing process. The nonconductive portions can be formed of silicon or silicone, Mylar, Mylar tape, rubber, hard rubber, plastic, nylon, elastomers, liquid-crystal polymers (LCPs), ceramics, or other nonconductive material or combination of materials.
Embodiments of the present invention can provide contacts and their connector assemblies that can be located in, and can connect to, various types of devices, such as portable computing devices, tablet computers, desktop computers, laptops, all-in-one computers, wearable computing devices, cell phones, smart phones, media phones, storage devices, keyboards, covers, cases, portable media players, navigation systems, monitors, power supplies, adapters, remote control devices, chargers, and other devices. These contacts and their connector assemblies can provide pathways for signals that are compliant with various standards such as Universal Serial Bus (USB), High-Definition Multimedia Interface (HDMI), Digital Visual Interface (DVI), Ethernet, DisplayPort, Thunderbolt, Lightning®, Joint Test Action Group (JTAG), test-access-port (TAP), Directed Automated Random Testing (DART), universal asynchronous receiver/transmitters (UARTs), clock signals, power signals, and other types of standard, non-standard, and proprietary interfaces and combinations thereof that have been developed, are being developed, or will be developed in the future. In various embodiments of the present invention, these interconnect paths provided by these connectors can be used to convey power, ground, signals, test points, and other voltage, current, data, or other information.
The above description of embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Thus, it will be appreciated that the invention is intended to cover all modifications and equivalents within the scope of the following claims.
This application claims the benefit of U.S. Provisional Patent Application No. 62/718,306, filed on Aug. 13, 2018, which is incorporated by reference.
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