PATENT DOCUMENT

Publication Number: US-9831600-B1
Application Number: US-201615275216-A
Country: US
Kind Code: B1

Title: Magnetic variable-force contacts

Abstract:
Variable-force contacts that may provide a large and stable contact force in a mated state, may provide a large difference in contact force between the mated and an unmated state, and may reduce stray flux in an unmated state. Examples may replace physical springs with magnetic force for improved reliability. These examples may position the magnets to reduce stray flux in an unmated state.

Claims:
What is claimed is: 
     
       1. A variable-force contact comprising:
 a housing; 
 a barrel extending laterally and having a rear portion and a front portion extending from a front of the housing; 
 a plunger in the barrel, the plunger having a contacting surface, the plunger able to move laterally within the barrel; 
 a contact magnet in the barrel between the plunger and the rear portion of the barrel, the contact magnet able to move laterally within the barrel; and 
 a shuttle magnet on at least a first side of the barrel, the shuttle magnet able to move laterally within the housing. 
 
     
     
       2. The variable-force contact of  claim 1 , wherein the shuttle magnet is located on at least a first side and a second side of the barrel, the first side opposite the second side. 
     
     
       3. The variable-force contact of  claim 1 , wherein the shuttle magnet and the contact magnet are concentric. 
     
     
       4. The variable-force contact of  claim 1 , wherein the shuttle magnet includes a first passage, the barrel located in the first passage. 
     
     
       5. The variable-force contact of  claim 1 , wherein the polarity of the contact magnet and the polarity of the shuttle magnet are oriented such that the shuttle magnet and the contact magnet repel. 
     
     
       6. The variable-force contact of  claim 5 , wherein when the variable-force contact is unmated, the shuttle magnet and the contact magnet repel such that the shuttle magnet moves laterally towards a rear of the housing and the contact magnet and plunger are positioned at a front the barrel. 
     
     
       7. The variable-force contact of  claim 6 , wherein when the variable-force contact is mated, the shuttle magnet is attracted to a front of the housing and the shuttle magnet and the contact magnet repel such the contact magnet and plunger are positioned at a front of the barrel. 
     
     
       8. The variable-force contact of  claim 7 , wherein when the variable-force contact is mated, the contact magnet applies a first force to the plunger, and when the variable-force contact is unmated, the contact magnet applies a second force to the plunger, the first force greater than the second force. 
     
     
       9. The variable-force contact of  claim 8 , wherein a backside of the plunger is asymmetrical. 
     
     
       10. The variable-force contact of  claim 1 , wherein the rear portion of the barrel is in the housing. 
     
     
       11. A variable-force contact comprising:
 a housing; 
 a barrel extending laterally and having a rear portion and a front portion extending from a front of the housing; 
 a plunger in the barrel, the plunger having a contacting surface, the plunger able to move laterally within the barrel; 
 a contact magnet in the barrel between the plunger and the rear portion of the barrel, the contact magnet able to move laterally within the barrel; 
 a spring between the contact magnet and the contacting surface of the plunger; and 
 a shuttle magnet on at least a first side of the barrel, the shuttle magnet able to move laterally within the housing. 
 
     
     
       12. The variable-force contact of  claim 11 , wherein the shuttle magnet is located on at least a first side and a second side of the barrel, the first side opposite the second side. 
     
     
       13. The variable-force contact of  claim 11 , wherein the shuttle magnet and the contact magnet are concentric. 
     
     
       14. The variable-force contact of  claim 11 , wherein the shuttle magnet includes a first passage, the barrel located in the first passage. 
     
     
       15. The variable-force contact of  claim 11 , wherein the polarity of the contact magnet and the polarity of the shuttle magnet are oriented such that the shuttle magnet and the contact magnet attract. 
     
     
       16. The variable-force contact of  claim 15 , wherein when the variable-force contact is unmated, the spring pushes the contact magnet and the plunger away from each other such that the contact magnet moves towards the rear portion of the barrel and plunger moves to the front of the barrel and the shuttle magnet and the contact magnet attract such that the shuttle magnet moves laterally towards a rear of the housing. 
     
     
       17. The variable-force contact of  claim 16 , wherein when the variable-force contact is mated, the shuttle magnet is attracted to a front of the housing, and the shuttle magnet and the contact magnet attract such the contact magnet pushes the plunger the front of the barrel. 
     
     
       18. The variable-force contact of  claim 17 , wherein when the variable-force contact is mated, the contact magnet applies a first force to the plunger, and when the variable-force contact is unmated, the contact magnet applies a second force to the plunger, the first force greater than the second force. 
     
     
       19. The variable-force contact of  claim 18 , wherein a backside of the plunger is asymmetrical. 
     
     
       20. The variable-force contact of  claim 11 , wherein the rear portion of the barrel is in the housing.

Description:
BACKGROUND 
     The number and types of electronic devices available to consumers have increased tremendously the past few years and this increase shows no signs of abating. Devices such as portable computing devices, tablet, desktop, and all-in-one computers, cell, smart, and media phones, storage devices, portable media players, navigation systems, monitors and other devices have become ubiquitous. 
     These devices often receive power and share data using cables that may have connector inserts on each end. The connector inserts may plug into connector receptacles on electronic devices, thereby forming one or more conductive paths for signals and power. Other devices may have connectors at a surface of a device. These devices may be connected to each other by placing them next to each other such that their connectors form electrical connections. 
     These various connectors may include various types of contacts. A variable-force contact may be used in either a connector insert or a connector receptacle, or it may be used in a connector at a surface of a device. 
     Spring-loaded contacts are an example of a variable-force contact. But conventional spring-loaded contacts may provide a contact force when mated to corresponding contacts that may vary considerably. For example, manufacturing tolerances may change one or more dimensions among conventional spring-loaded contacts in a group. The changes brought about by these manufacturing tolerances may lead to changes and inconsistencies in contact force, which may lead to changes and inconsistencies in contact resistance. 
     Also, springs in conventional spring-loaded contacts may provide a similar force when in a mated and unmated state. This may mean that the springs provide excessive force when unmated and insufficient force when mated. 
     Thus, what is needed are variable-force contacts that may provide a high and stable contact force in a mated state and may provide a large difference in contact force between the mated and an unmated state. 
     SUMMARY 
     Accordingly, embodiments of the present invention may provide variable-force contacts that may provide a high and stable contact force in a mated state and may provide a large difference in contact force between the mated and an unmated state. Various embodiments of the present invention may replace physical springs with magnetic force for improved reliability. These and other embodiments of the present invention may position the magnets to reduce stray flux in an unmated state. 
     An embodiment of the present invention may provide a variable-force contact. The variable-force contact may include a housing. The housing may be separate from a device enclosure or it may be the same as a device enclosure, or structures may be shared between the housing and device enclosure. A barrel may extend laterally through the housing. The barrel may include a rear portion located in the housing and a front portion extending from a front of the housing. A plunger may be located at least partially in the barrel. The plunger may have a contacting surface. The contacting surface of the plunger may extend beyond a front of the barrel. The contacting surface may mate with corresponding contact surfaces of corresponding contacts in corresponding connectors. The plunger may be free to move laterally within the barrel. 
     In these and other embodiments of the present invention, two magnets may be used to provide a contact force at the connecting surface of the plunger. The two magnets may include a contact magnet in the barrel between the plunger and a rear of the barrel. The contact magnet may be free to move laterally within the barrel. The two magnets may further include a shuttle magnet. The shuttle magnet may be located on at least a first side of the barrel. The shuttle magnet may be free to move laterally within the housing. In one specific example, the contact magnet and shuttle magnet may be oriented to each other to provide a repelling force. That is, a North pole of the contact magnet may face a North pole of the shuttle magnet, or a South pole of the contact magnet may face a South pole of the shuttle magnet. 
     In these and other embodiments of the present invention, the shuttle magnet may be located on a first side and a second side of the barrel, the first side opposite the second side. In these and other embodiments of the present invention, the shuttle magnet and the contact magnet may be concentric. When they are concentric, the shuttle magnet may include a first passage and the barrel may be located in the first passage. 
     In these and other embodiments of the present invention, when the variable-force contact is unmated, the shuttle magnet and the contact magnet may repel such that the shuttle magnet moves laterally towards the rear of the housing. The contact magnet and plunger may be driven such that they are positioned at a front the barrel. In this configuration, the shuttle magnet and the contact magnet may be at or near a maximum distance or spacing for that particular variable-force contact. This may reduce a contact force at the contacting surface of the plunger in the unmated state. This may help to avoid an amount of incidental wear and prevent damage to the variable-force contact. For example, the variable-force contact may retract and avoid damage when it is hit or struck by an object. The presence of some force may ensure that the plunger remains in contact with an end of the barrel in an unmated state. This may prevent contaminants from entering the barrel of the variable-force contact. 
     In these and other embodiments of the present invention, when the variable-force contact is mated to a corresponding contact, the shuttle magnet may be attracted to a front of the housing by a magnetic element of a corresponding connector. The contact magnet may be repelled such the contact magnet and plunger are positioned at a front of the barrel. In this configuration, the shuttle magnet and the contact magnet may be at or near a minimum distance or spacing for that particular variable-force contact. This may increase a contact force at the contacting surface of the plunger in the mated state. This increase in force may reduce an impedance of a connection made between the variable-force contact and a corresponding contact. This mated contact force may be larger than the unmated contact force. 
     In these and other embodiments of the present invention, the mated force may be a function of the repelling magnetic force between the contact magnet and the shuttle magnet. In the mated configuration, the contact magnet may be in a passage in the shuttle magnet. The result may be that the repelling magnetic force may be a weak function of the exact placement of the contact magnet relative to the shuttle magnet. This may provide a stable contact force as the sizes and spacings of the component parts of the variable-force contact vary over manufacturing tolerances. 
     In these and other embodiments of the present invention, the variable-force contact may generate only a limited, reduced, or zero force pushing against its housing. This may stand in contrast to spring-loaded contacts that may include a spring that may push a device housing the spring-loaded contact away from a corresponding mated device. This pushing may reduce a resulting contact force. By removing this push force provided by the spring, the resulting contact force may be maintained at a high level when the variable-force contact is mated. 
     In these and other embodiments of the present invention, when the variable-force contact is unmated, the shuttle magnet may be driven by the repelling magnetic force of the contact magnet to a rear of the housing. In this position, the larger shuttle magnet may be further away from a surface of an electronic device housing the variable-force contact. This may reduce stray magnetic flux at a surface of the electronic device in the unmated state. This may protect against damage to magnetic stripes on credit cards and licenses and may prevent data loss in various data storage media. 
     In these and other embodiments of the present invention, it may be desirable that when the variable-force contact is mated, current may flow through the plunger and into a barrel. That is, it may be undesirable in the mated state for the plunger to be centered in the barrel and not contacting an inside edge of the barrel, as this would create an open circuit. Accordingly, in these and other embodiments of the present invention, a backside of the plunger may be asymmetrical. This may help to prevent the plunger from being centered in the barrel and creating an open circuit by having the contact magnet push an edge of the plunger into a side of the barrel. 
     In these and other embodiments of the present invention, no physical spring may be present. This may help to avoid problems where springs may become tangled or where they may be destroyed by excessive current flow. The elimination of a spring may improve the reliability of a variable-force contact, though these and other embodiments of the present invention may continue to make use of a spring. 
     Another embodiment of the present invention may provide another variable-force contact. The variable-force contact may include a housing. The housing may be separate from a device enclosure or it may be the same as a device enclosure, or structures may be shared between the housing and device enclosure. A barrel may extend laterally through the housing. The barrel may include a rear portion located in the housing and a front portion extending from a front of the housing. A plunger may be located at least partially in the barrel. The plunger may have a contacting surface. The contacting surface may extend beyond a front of the barrel. The contacting surface may mate with corresponding contact surfaces of corresponding contacts in corresponding connectors. The plunger may be free to move laterally within the barrel. 
     In these and other embodiments of the present invention, two magnets may be used to provide a contact force at the connecting surface of the plunger. As before, the two magnets may include a contact magnet in the barrel between the plunger and a rear of the barrel. The contact magnet may be free to move laterally within the barrel. The two magnets may further include a shuttle magnet. The shuttle magnet may be located on at least a first side of the barrel. The shuttle magnet may be free to move laterally within the housing. 
     In these and other embodiments of the present invention, the shuttle magnet may be located on a first side and a second side of the barrel, the first side opposite the second side. In these and other embodiments of the present invention, the shuttle magnet and the contact magnet may be concentric. When they are concentric, the shuttle magnet may include a first passage and the barrel may be located in the first passage. 
     In these and other embodiments of the present invention, a protective structure may be used to protect the contact magnet from the spring. This protective structure may be conductive or nonconductive. It may be located in the barrel between the spring and the contact magnet. It may be free to move laterally in the barrel. It may be attached to the contact magnet or it may be free to move relative to the contact magnet. The protective structure may include a tail portion substantially surrounded by the spring. This may keep the spring aligned to the protective structure and may help to keep the spring from being tangled with the protective structure. On its opposite end, the spring may terminate in a recess in a back surface of the plunger, which may help to keep the spring from becoming tangled with the plunger. 
     In one specific example, instead of being oriented to provide a repelling force as in the above example, the contact magnet and shuttle magnet may be oriented to each other to provide an attractive force. That is, a North pole of the contact magnet may face a South pole of the shuttle magnet, or a South pole of the contact magnet may face a North pole of the shuttle magnet. 
     In these and other embodiments of the present invention, when the variable-force contact is unmated, the spring may push the contact magnet away from the plunger. The shuttle magnet and the contact magnet may attract each other. The shuttle magnet may move laterally such that the contact magnet is near a center of the shuttle magnet. In this configuration, the shuttle magnet and the contact magnet may be at or near a minimum distance or spacing for that particular variable-force contact. This may reduce a contact force at the contacting surface of the plunger in the unmated state. This may help to avoid an amount of incidental wear and prevent damage to the variable-force contact. For example, the variable-force contact may retract and avoid damage when it is hit or struck by an object. The presence of some force may ensure that the plunger remains in contact with an end of the barrel in an unmated state. This may prevent contaminants from entering the barrel of the variable-force contact. 
     In these and other embodiments of the present invention, when the variable-force contact is mated, the shuttle magnet may be attracted to a front of the housing by a magnetic element of a corresponding contact. The contact magnet may be attracted to the shuttle contact such the contact magnet and plunger are positioned at a front of the barrel. In this configuration, the shuttle magnet and the contact magnet may be at or near a maximum distance or spacing for that particular variable-force contact. This may increase a contact force at the contacting surface of the plunger in the mated state. This increase in force may reduce an impedance of a connection made between the variable-force contact and a corresponding contact. This mated contact force may be larger than the unmated contact force. 
     In these and other embodiments of the present invention, the mated force may be a function of the attractive magnetic force between the contact magnet and the shuttle magnet. In the mated configuration, the contact magnet may be in a passage in the shuttle magnet. The result may be that the attractive magnetic force may be a weak function of the exact placement of the contact magnet relative to the shuttle magnet. This may provide a stable contact force as the sizes and spacings of the component parts of the variable-force contact vary over manufacturing tolerances. 
     In these and other embodiments of the present invention, the variable-force contact may generate only a limited, reduced, or zero force pushing against its housing. This may stand in contrast to spring-loaded contacts that may include a spring that may push a device housing the spring-loaded contact away from a corresponding mated device. This pushing may reduce a resulting contact force. By removing this push force provided by a spring, the resulting contact force may be maintained at a high level when the variable-force contact is mated. 
     In these and other embodiments of the present invention, when the variable-force contact is unmated, the shuttle magnet may be driven by the attractive magnetic force of the contact magnet to a location near a rear of the housing. In this position, the larger shuttle magnet may be further away from a surface of an electronic device housing the variable-force contact. This may reduce stray magnetic flux at a surface of the electronic device in the unmated state. This may protect against damage to magnetic stripes on credit cards and licenses and may prevent data loss in various data storage media. 
     In these and other embodiments of the present invention, it may be desirable that when the variable-force contact is mated, current may flow through the plunger and into a barrel. That is, it may be undesirable in the mated state for the plunger to be centered in the barrel and not contacting an inside edge of the barrel, as this would create an open circuit. Accordingly, in these and other embodiments of the present invention, a surface of the protective structure closest to the plunger may be asymmetrical. In these and other embodiments of the present invention, a backside of the plunger may be asymmetrical instead of the surface of the protective structure. Either of these may help to prevent the plunger from being centered in the barrel and creating an open circuit by having the contact magnet push an edge of the plunger into a side of the barrel. 
     Another embodiment of the present invention may provide another variable-force contact. The variable-force contact may include a housing. The housing may be separate from a device enclosure or it may be the same as a device enclosure, or structures may be shared between the housing and device enclosure. A barrel may extend laterally through the housing. The barrel may include a rear portion located in the housing and a front portion extending from a front of the housing. A plunger may be located at least partially in the barrel. The plunger may have a contacting surface that may extend beyond a front of the barrel. The contacting surface may mate with corresponding contact surfaces of corresponding contacts in corresponding connectors. The plunger may be free to move laterally within the barrel. A magnet may be located in the barrel. When a connection is made to a corresponding contact, the magnet may be attracted to a magnetic element in the corresponding connector. The magnet may move forward against the plunger thereby providing a high contacting force in the mated state. 
     This variable-force contact may include a spring between magnet and the plunger. When the variable-force contact is in the unmated state, the spring may push the magnet away from the plunger. This may reduce a contact force at the plunger in the unmated state. The repositioning of the magnet away from the front of the variable-force contact may reduce the stray magnetic flux at a surface of the device. 
     In various embodiments of the present invention, plungers, barrels contacts, brackets, barrels, and other conductive portions of a variable-force contact may be formed by stamping, forging, metal-injection molding, machining, micro-machining, 3-D printing, or other manufacturing process. The conductive portions may be formed of stainless steel, steel, copper, copper titanium, phosphor bronze, or other material or combination of materials. They may be plated or coated with nickel, gold, or other material. The nonconductive portions, such as the housings and other structures may be formed using injection or other molding, 3-D printing, machining, or other manufacturing process. The nonconductive portions may be formed of silicon or silicone, rubber, hard rubber, plastic, nylon, liquid-crystal polymers (LCPs), ceramics, or other nonconductive material or combination of materials. The magnets may be rare-earth magnets or other type of magnets. 
     Embodiments of the present invention may provide variable-force contacts that may be used in connector receptacles and connector inserts that may be located in, may connect to, or may be on the surface of 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, portable media players, navigation systems, monitors, power supplies, video delivery systems, adapters, styluses, remote control devices, chargers, and other devices. These variable-force contacts may provide pathways for signals that are compliant with various standards such as one of the Universal Serial Bus (USB) standards including USB Type-C, 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. Other embodiments of the present invention may provide connector structures that may be used to provide a reduced set of functions for one or more of these standards. In various embodiments of the present invention, these variable-force contacts may be used to convey power, ground, signals, test points, and other voltage, current, data, or other information. 
     Various embodiments of the present invention may incorporate one or more of these and the other features described herein. A better understanding of the nature and advantages of the present invention may be gained by reference to the following detailed description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an electronic system that may be improved by the incorporation of embodiments of the present invention; 
         FIG. 2  illustrates a connector insert according to an embodiment of the present invention; 
         FIG. 3  illustrates a variable-force contact according to an embodiment of the present invention; 
         FIG. 4  illustrates the variable-force contact of  FIG. 3  in a mated state; 
         FIG. 5  illustrates a contact force curve for the magnets of the variable-force contact of  FIG. 3 ; 
         FIG. 6  is a flow chart showing the operation of the variable-force contact of  FIG. 3 ; 
         FIG. 7  illustrates another variable-force contact according to an embodiment of the present invention; 
         FIG. 8  illustrates the variable-force contact of  FIG. 7  in a mated state; 
         FIG. 9  illustrates a contact force curve for the magnets of the variable-force contact of  FIG. 7 ; 
         FIG. 10  is a flow chart showing the operation of the variable-force contact of  FIG. 7 ; 
         FIG. 11  illustrates another variable-force contact according to an embodiment of the present invention; and 
         FIG. 12  illustrates the variable-force contact of  FIG. 11  in a mated state. 
     
    
    
     DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
       FIG. 1  illustrates an electronic system that may be improved by the incorporation of embodiments of the present invention. This figure, as with the other included figures, is shown for illustrative purposes and does not limit either the possible embodiments of the present invention or the claims. 
     This figure includes electronic device  110 . In this specific example, electronic device  110  may be a laptop computer. In other embodiments of the present invention, electronic device  110  may be a tablet computer, cell, media, or smart phone, global positioning device, media player, or other device. 
     Electronic device  110  may include a battery. The battery may provide power to electronic circuits in electronic device  110 . This battery may be charged using power adapter  120 . Specifically, power adapter  120  may receive power from an external source, such as a wall outlet or car charger. Power adapter  120  may convert received external power, which may be AC or DC power, to DC power, and it may provide the converted DC power over cable  130  to connector insert  132 . In other embodiments of the present invention, connector insert  132  may be coupled through cable  130  to another type of device. Connector insert  132  may be arranged to mate with connector receptacle  112  on electronic device  110 . Power may be received at connector receptacle  112  from connector insert  132  and provided to the battery and electronic circuitry in electronic device  110 . In other embodiments of the present invention, data or other types of signals may also be provided to electronic device  110  via connector insert  132 . Power and data may be transferred using variable-force contacts according to embodiments of the present invention. These contacts may be located in connector insert  132 , connector receptacle  112 , or on the surface of an electronic device, such as electronic device  110 . Another connector insert that may include variable-force contacts is shown in the following figure. 
       FIG. 2  illustrates a connector insert  132  according to an embodiment of the present invention. Connector insert  132  may include an attraction plate  210 , shield or cover  220 , cable  230 , and strain relief  240 . Attraction plate  210  may include front surface  212 . Front surface  212  may include opening  260  for contacts  250 ,  252 ,  254 ,  256 , and  258 . In a specific embodiment of the present invention, contacts  250  and  258  may convey ground, contacts  252  and  256  may convey power, while contact  254  may be used to detect that a connection has been formed. In this specific example, contacts  250  and  258  protrude in front of the other contacts, such that ground paths are formed before power is applied when connector insert  132  is mated with a corresponding connector receptacle. 
     In various embodiments of the present invention, contacts  250 ,  252 ,  254 ,  256 , and  258  may be variable-force contacts. Examples of variable-force contacts according to embodiments of the present invention are shown in the following figures. 
     Again, embodiments of the present invention may provide variable-force contacts that may provide a high and stable contact force in a mated state and may provide a large difference in contact force between the mated and an unmated state. Various embodiments of the present invention may replace physical springs with magnetic force for improved reliability. These and other embodiments of the present invention may position these magnets to provide a reduced stray flux in an unmated state. Examples are shown in the following figures. 
       FIG. 3  illustrates a variable-force contact according to an embodiment of the present invention. Variable-force contact  300  may include housing  310 . Housing  310  may be separate from a device enclosure (not shown) or it may be the same as a device enclosure, or structures (not shown) may be shared between housing  310  and a device enclosure. Barrel  320  may extend laterally through housing  310 . Barrel  320  may include a rear portion located in housing  310  and a front portion extending from a front of housing  310 . Plunger  350  may be located at least partially in barrel  320 . Plunger  350  may have contacting surface  352 . Contacting surface  352  may extend beyond barrel  320  and may mate with corresponding contact surfaces of corresponding contacts in corresponding connectors. Plunger  350  may be free to move laterally within barrel  320 . Barrel  320  may terminate in barrel contact  360 . Bracket  370  may connect to barrel contact  370  and may further connect to flexible circuit board  380 . In this way, power, data, ground, or other signals or voltage may be transferred between device via a path including plunger  350 , barrel  320 , barrel contact  360 , bracket  370 , and flexible circuit board  380 . 
     In this example, two magnets may be used to provide a contact force at contacting surface  352  of plunger  350 . The two magnets may include contact magnet  340  in barrel  320  between plunger  350  and barrel contact  360 . Contact magnet  340  may be free to move laterally within barrel  320 . The two magnets may further include shuttle magnet  330 . Shuttle magnet  330  may be located on at least a first side of barrel  320 . Shuttle magnet  330  may be free to move laterally within housing  310 . In one specific example, contact magnet  340  and shuttle magnet  330  may be oriented relative to each other in order to provide a repelling force. That is, a North pole of contact magnet  340  may face a North pole of shuttle magnet  330 , or a South pole of contact magnet  340  may face a South pole of shuttle magnet  330 . In this example, face  343  of contact magnet and face  333  of shuttle magnet  330  may have the same poles. 
     In these and other embodiments of the present invention, shuttle magnet  330  may be located on a first side and a second side of barrel  320 , the first side opposite the second side. In these and other embodiments of the present invention, shuttle magnet  330  and the contact magnet  340  may be concentric. When they are concentric, shuttle magnet  330  may include a first passage  337  and barrel  320  may be located in the first passage  337 . 
     In these and other embodiments of the present invention, when variable-force contact  300  is unmated, shuttle magnet  330  and contact magnet  340  may repel such that shuttle magnet  330  moves laterally towards the rear of housing  310 . Contact magnet  340  and plunger may be driven such that they are positioned at a front barrel  320 . In this configuration, shuttle magnet  330  and contact magnet  340  may be at or near a maximum distance or spacing for variable-force contact  300 . That is, distance  390  from center line  342  of contact magnet  340  to center line  332  of shuttle contact  330  may be at or near a maximum for variable-force contact  300 . This may reduce a contact force at contacting surface  352  of plunger  350  in the unmated state. This may help to avoid incidental wear and prevent damage to variable-force contact  300 . For example, plunger  350  of variable-force contact  300  may retract and avoid damage when it is hit or struck by an object. The presence of some force may ensure that plunger  350  remains in contact with an end of barrel  320  in an unmated state. This may prevent contaminants from entering barrel  320  of variable-force contact  300 . 
       FIG. 4  illustrates the variable-force contact of  FIG. 3  in a mated state. In these and other embodiments of the present invention, when variable-force contact  300  is mated with contact  410 , shuttle magnet  330  may be attracted to a front of housing  310  by a magnetic element of a corresponding connector that includes corresponding contact  410 . Contact magnet  340  may be repelled such contact magnet  340  and plunger are positioned at a front of barrel  320 . In this configuration, shuttle magnet  330  and contact magnet  340  may be at or near a minimum distance or spacing for variable-force contact  300 . That is, distance  390  from center line  342  of contact magnet  340  to center line  332  of shuttle contact  330  may be at or near a minimum for this variable-force contact  300 . This may increase a contact force at contacting surface  352  of plunger  350  in the mated state. This increase in force may reduce an impedance of a connection made between variable-force contact  300  and corresponding contact  410 . This mated contact force may be larger than the unmated contact force. 
     In these and other embodiments of the present invention, the mated force may be a function of the repelling magnetic force between contact magnet  340  and shuttle magnet  330 . In the mated configuration, contact magnet  340  may be in a passage  337  in shuttle magnet  330 . The result may be that the repelling magnetic force may be a weak function of the exact placement of contact magnet  340  relative to shuttle magnet  330 . This may provide a stable contact force as the sizes and spacings of the component parts of variable-force contact  300  vary over manufacturing tolerances. 
     In these and other embodiments of the present invention, variable-force contact  300  may generate only a limited, reduced, or zero force pushing against its housing. This may stand in contrast to spring-loaded contacts that may include a spring that may push a device housing the spring-loaded contact away from a corresponding mated device. This pushing may reduce a resulting contact force. By removing this pushing, the resulting contact force may be maintained at a high level when variable-force contact  300  is mated. 
     In these and other embodiments of the present invention, when variable-force contact  300  is unmated, shuttle magnet  330  may be driven by the repelling magnetic force of contact magnet  340  to a rear of housing  310 . In this position, the larger shuttle magnet  330  may be further away from a surface of an electronic device housing variable-force contact  300 . This may reduce stray magnetic flux at a surface of the electronic device in the unmated state. This in turn may protect against damage to magnetic stripes on credit cards and licenses and may prevent data loss in various data storage media. 
     In these and other embodiments of the present invention, it may be desirable that when variable-force contact  300  is mated, current may flow through plunger  350  and into barrel  320 . That is, it may be undesirable in the mated state for plunger  350  to be centered in barrel  320  and not contacting an inside edge of barrel  320 , as this would create an open circuit. Accordingly, in these and other embodiments of the present invention, a backside of plunger  350  may be asymmetrical, as shown here and in  FIG. 3  by the inclusion of feature  354 . This may help to prevent plunger  350  from being centered in barrel  320  and creating an open circuit by having contact magnet  340  push an edge of plunger  350  into a side of barrel  320 . 
       FIG. 5  illustrates a contact force curve for the magnets of the variable-force contact of  FIG. 3 . This force curve graphs a force available at contacting surface  352  of plunger  350  as a function of a distance between center lines of contact magnet  340  and shuttle magnet  330 . In this example, at point  510 , contact magnet  340  may be centered in shuttle magnet  330  and thought the magnets repel, there is no net force on the magnet. As contact magnet  340  moves out towards and edge and out of shuttle magnet  330 , the force may increase as shown by line segment  520 . A mating force is shown at point  530 . The rate of change of contact force near point  530  (the derivative of the curve at point  530 ) may be flat, meaning that changes in the distance between centerlines of contact magnet  340  and shuttle magnet  330  might not strongly effect contact force. This may allow variations in components size and spacings that may be due to manufacturing tolerances and other variables to have a limited effect on contact force. The high value may reduce contact resistance in the connection between variable-force contact  300  and contact  410 . When variable-force contact  300  is disconnected from contact  410 , the distance between centerlines of contact magnet  340  and shuttle magnet  330  may increase to point  540 . Point  540  may show the unmated contact force for variable-force contact  300 . This low contact force may help to avoid incidental wear and prevent damage to variable-force contact  300 . 
       FIG. 6  is a flow chart showing the operation of the variable-force contact of  FIG. 3 . In act  610 , variable-force contact  300  may be unmated. In act  620 , contact magnet  340  and shuttle magnet  330  may repel. Shuttle magnet  340  may be driven to a rear of housing  310  in act  630 . Again, this may reduce stray flux at a surface of an electronic device housing variable-force contact  300 . In act  340 , the distance between center lines  342  and  332  of contact magnet  340  and shuttle magnet  330  may be at a maximum thereby reducing the contact force. 
     In act  650 , variable-force contact  300  may be mated. Shuttle magnet  330  may be attracted to a front of variable-force contact  300  by a magnetic element of a connector having mating contact  410 , in act  660 . Shuttle magnet  330  may drive contact magnet  340  forward in act  670 . The distance between center lines  342  and  332  of contact magnet  340  and shuttle magnet  330  may be at a minimum thereby increasing the contact force in act  680 . Again, this increased force may reduce a resistance of the connection between variable-force contact  300  and mating contact  410 . 
       FIG. 7  illustrates another variable-force contact according to an embodiment of the present invention. Variable-force contact  700  may include housing  710 . Housing  710  may be separate from a device enclosure or it may be the same as a device enclosure, or structures may be shared between housing  710  and device enclosure. Barrel  720  may extend laterally through housing  710 . Barrel  720  may include a rear portion located in housing  710  and a front portion extending from a front of housing  710 . Plunger  750  may be located at least partially in barrel  720 . Plunger  750  may have contacting surface  752 . Contacting surface  752  may extend beyond a front of plunger  750 . Contacting surface  752  may mate with corresponding contact surfaces of corresponding contacts in corresponding connectors. Plunger  750  may be free to move laterally within barrel  720 . Barrel  720  may terminate in barrel contact  760 . Bracket  770  may connect to barrel contact  770  and may further connect to flexible circuit board  780 . In this way, power, data, ground, or other signals or voltage may be transferred between device via a path including plunger  750 , barrel  720 , barrel contact  760 , bracket  770 , and flexible circuit board  780 . 
     In these and other embodiments of the present invention, two magnets may be used to provide a contact force at the connecting surface of plunger  750 . As before, the two magnets may include contact magnet  740  in barrel  720  between plunger  750  and a rear of barrel  720 . Contact magnet  740  may be free to move laterally within barrel  720 . The two magnets may further include a shuttle magnet. Shuttle magnet  730  may be located on at least a first side of barrel  720 . Shuttle magnet  730  may be free to move laterally within housing  710 . 
     In these and other embodiments of the present invention, shuttle magnet  730  may be located on a first side and a second side of barrel  720 , the first side opposite the second side. In these and other embodiments of the present invention, shuttle magnet  730  and the contact magnet  740  may be concentric. When they are concentric, the shuttle magnet may include a first passage  737  and barrel  720  may be located in the first passage  737 . 
     In these and other embodiments of the present invention, a protective structure  744  may be used to protect contact magnet  740  from spring  754 . This protective structure  744  may be conductive or nonconductive. It may be located in barrel  720  between spring  754  and contact magnet  740 . It may be free to move laterally in barrel  720 . It may be attached to contact magnet  740  or it may be free to move relative to contact magnet  740 . The protective structure  744  may include a tail portion  746  substantially surrounded by spring  754 . This may keep spring  754  aligned to the protective structure  744  and may help to keep spring  754  from being tangled with the protective structure  744 . On its opposite end, spring  754  may terminate in a recess in a back surface of plunger  750 , which may help to keep spring  754  from becoming tangled with plunger  750 . 
     In one specific example, instead of being oriented to provide a repelling force as in the above example, contact magnet  740  and shuttle magnet may be oriented to each other to provide an attractive force. That is, a North pole of contact magnet  740  may face a South pole of shuttle magnet  730 , or a South pole of contact magnet  740  may face a North pole of shuttle magnet  730 . In this example, face  743  of contact magnet and face  733  of shuttle magnet  330  have opposite poles. 
     In these and other embodiments of the present invention, when the variable-force is unmated, spring  754  may push contact magnet  740  away from plunger  750 . Shuttle magnet  730  and contact magnet  740  may attract each other. Shuttle magnet  730  may move laterally such that contact magnet  740  is near a center of shuttle magnet  730 . In this configuration, shuttle magnet  730  and contact magnet  740  may be at or near a minimum distance or spacing for variable-force contact  700 . That is, distance  790  between center line  732  of shuttle magnet  730  and center line  742  of contact magnet  740  may be at or near a minimum distance or spacing for variable-force contact  700 . This may reduce a contact force at contacting surface  752  of plunger  750  in the unmated state. This may help to avoid incidental wear and prevent damage to the variable-force contact. For example, plunger  750  of variable-force contact  700  may retract and avoid damage when it is hit or struck by an object. The presence of some force may ensure that plunger  750  remains in contact with an end of barrel  720  in an unmated state. This may prevent contaminants from entering barrel  720  of the variable-force contact. 
       FIG. 8  illustrates the variable-force contact of  FIG. 7  in a mated state. When variable-force contact  700  is mated, shuttle magnet  730  may be attracted to a front of housing  710  by a magnetic element of a corresponding contact  810 . Contact magnet  740  may be attracted to the shuttle contact such contact magnet  740  and plunger are positioned at a front of barrel  720 . In this configuration, shuttle magnet  730  and contact magnet  740  may be at or near a maximum distance or spacing for variable-force contact  700 . That is, a distance between center line  732  of shuttle magnet  730  and center line  742  of contact magnet  740  may be at or near a maximum distance or spacing for variable-force contact  700 . This may increase a contact force at contacting surface  752  of plunger  750  in the mated state. This increase in force may reduce an impedance of a connection made between the variable-force contact  700  and corresponding contact  810 . This mated contact force may be larger than the unmated contact force. 
     In these and other embodiments of the present invention, the mated force may be a function of the attractive magnetic force between contact magnet  740  and shuttle magnet  730 . In the mated configuration, contact magnet  740  may be in a passage  737  in shuttle magnet  730 . The result may be that the attractive magnetic force may be a weak function of the exact placement of contact magnet  740  relative to shuttle magnet  730 . This may provide a stable contact force as the sizes and spacings of the component parts of variable-force contact  700  vary over manufacturing tolerances. 
     In these and other embodiments of the present invention, the variable-force contact may generate only a limited, reduced, or zero force pushing against its housing. This may stand in contrast to spring-loaded contacts that may include spring  754  that may push a device housing spring  754 -loaded contact away from a corresponding mated device. This pushing may reduce a resulting contact force. By removing this push force provided by the spring, the resulting contact force may be maintained at a high level when the variable-force contact is mated. 
     In these and other embodiments of the present invention, when variable-force contact  700  is unmated, shuttle magnet  730  may be driven by the attractive magnetic force of contact magnet  740  to a location near a rear of housing  710 . In this position, the larger shuttle magnet  730  may be further away from a surface of an electronic device housing variable-force contact  700 . This may reduce stray magnetic flux at a surface of the electronic device in the unmated state. This in turn may protect against damage to magnetic stripes on credit cards and licenses and may prevent data loss in various data storage media. 
     In these and other embodiments of the present invention, it may be desirable that when the variable-force contact  700  is mated, current may flow through plunger  750  and into barrel  720 . That is, it may be undesirable in the mated state for plunger  750  to be centered in barrel  720  and not contacting an inside edge of barrel  720 , as this would create an open circuit. Accordingly, in these and other embodiments of the present invention, a surface of the protective structure  744  closest to plunger  750  may be asymmetrical, shown here and in  FIG. 7  by the inclusion of feature  748 . In these and other embodiments of the present invention, a backside of plunger  750  may be asymmetrical instead of the surface of the protective structure  744 . Either of these may help to prevent plunger  750  from being centered in barrel  720  and creating an open circuit by having contact magnet  740  push an edge of plunger  750  into a side of barrel  720 . 
       FIG. 9  illustrates a contact force curve for the magnets of the variable-force contact of  FIG. 7 . This force curve graphs a force available at contacting surface  752  of plunger  750  as a function of a distance between center lines of contact magnet  740  and shuttle magnet  730 . In this example, at point  910 , contact magnet  740  may be centered in shuttle magnet  730  and thought the magnets attract, there may be little net force on the magnet. As contact magnet  740  moves out towards and edge and out of shuttle magnet  730 , the force may increase to the unmated force shown at point  920 . The low contact force at point  920  may help to prevent damage to variable-force contact  700 . When variable-force contact  700  is connected to contact  410 , the distance between centerlines of contact magnet  740  and shuttle magnet  730  may increase to point  940 . Point  940  may show the mated contact force for variable-force contact  700 . The rate of change of contact force near point  940  (the derivative of the curve at point  940 ) may be flat, meaning that changes in the distance between centerlines of contact magnet  740  and shuttle magnet  730  do not strongly effect contact force. This may allow variations in components size and spacings that may be due to manufacturing tolerances and other variables to have a limited effect on contact force. The high value may reduce contact resistance in the connection between variable-force contact  700  and contact  410 . 
       FIG. 10  is a flow chart showing the operation of the variable-force contact of  FIG. 3 . In act  1010 , variable-force contact  700  may be unmated. In act  1020 , contact magnet  740  and shuttle magnet  730  may attract. Spring  754  may push contact magnet  740  back into housing  710 . Shuttle magnet  740  may be driven near a rear of housing  710  in act  1030 . Again, this may reduce stray flux at a surface of an electronic device housing variable-force contact  700 . In act  1040 , the distance between center lines  742  and  732  of contact magnet  740  and shuttle magnet  730  may be at a minimum thereby reducing the contact force. 
     In act  1050 , variable-force contact  700  may be mated. Shuttle magnet  730  may be attracted to a front of variable-force contact  700  by a magnetic element of a connector having mating contact  410 , in act  1060 . Shuttle magnet  730  may drive contact magnet  740  forward in act  1070 . The distance between center lines  742  and  732  of contact magnet  740  and shuttle magnet  730  may be at a maximum thereby increasing the contact force in act  1080 . Again, this increased force may reduce a resistance of the connection between variable-force contact  700  and mating contact  410 . 
       FIG. 11  illustrates another variable-force contact according to an embodiment of the present invention. Variable-force contact  1100  may include a housing (not shown). The housing may be separate from a device enclosure (not shown) or it may be the same as a device enclosure, or structures (not shown) may be shared between the housing and device enclosure. Barrel  1110  may extend laterally through the housing. Barrel  1110  may include a rear portion located in the housing and a front portion extending from a front of the housing. Plunger  1120  may be located at least partially in barrel  1110 . Plunger  1120  may have contacting surface  1122  extending beyond a front of plunger  1120 . Contacting surface  1122  may mate with corresponding contact surfaces of corresponding contacts in corresponding connectors. Plunger  1120  may be free to move laterally within barrel  1110 . Magnet  1140  may be located in barrel  1140 . 
     Variable-force contact  1100  may include spring  1130  between magnet  1140  and plunger  1120 . When variable-force contact  1100  is in the unmated state, spring  1130  may push magnet  1140  away from plunger  1120 . This may reduce a contact force at plunger  1120  in the unmated state. The repositioning of magnet  1140  away from the front of variable-force contact  1100  may reduce the stray magnetic flux at a surface of the electronic device. 
       FIG. 12  illustrates the variable-force contact of  FIG. 11  in a mated state. When contact  1210  is mated to variable-force contact  1100 , magnet  1140  may be attracted to a magnetic element (not shown) in the corresponding connector (not shown). Magnet  1140  may move forward against plunger  1120  thereby providing a high contacting force in the mated state. 
     In various embodiments of the present invention, plungers, contacts, brackets, barrels, and other conductive portions of a variable-force contact may be formed by stamping, forging, metal-injection molding, machining, micro-machining, 3-D printing, or other manufacturing process. The conductive portions may be formed of stainless steel, steel, copper, copper titanium, phosphor bronze, or other material or combination of materials. They may be plated or coated with nickel, gold, or other material. The nonconductive portions, such as the housings and other structures may be formed using injection or other molding, 3-D printing, machining, or other manufacturing process. The nonconductive portions may be formed of silicon or silicone, rubber, hard rubber, plastic, nylon, liquid-crystal polymers (LCPs), ceramics, or other nonconductive material or combination of materials. The magnets may be rare-earth magnets or other type of magnets. 
     Embodiments of the present invention may provide variable-force contacts that may be used in connector receptacles and connector inserts that may be located in, may connect to, or may be on the surface of 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, portable media players, navigation systems, monitors, power supplies, video delivery systems, adapters, styluses, remote control devices, chargers, and other devices. These variable-force contacts may provide pathways for signals that are compliant with various standards such as one of the Universal Serial Bus standards including USB Type-C, High-Definition Multimedia Interface, Digital Visual Interface, Ethernet, DisplayPort, Thunderbolt, Lightning, Joint Test Action Group, test-access-port, Directed Automated Random Testing, universal asynchronous receiver/transmitters, 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. Other embodiments of the present invention may provide connector structures that may be used to provide a reduced set of functions for one or more of these standards. In various embodiments of the present invention, these variable-force contacts may 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.

Metadata:
Filing Date: 20160923
Publication Date: 20171128
Grant Date: 20171128
Priority Date: 20160923
Inventors: LECLERC MICHAEL E.
NARAJOWSKI DAVID H.
DEGNER BRETT W.
Assignee: APPLE INC
CPC Classifications: [{"code": "H01R13/629", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/6205", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01R13/15", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R2201/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/2421", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R2201/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/2421", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/6205", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01R13/6205", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 60407679