PATENT DOCUMENT

Publication Number: US-11469040-B2
Application Number: US-202016893152-A
Country: US
Kind Code: B2

Title: Wireless magnetic charger with solenoids

Abstract:
This application relates to a wireless charger with increased efficiency during operation. The wireless charging assembly includes a wireless charger and an electronic device. A transmitter coil in the wireless charger can induct magnetic flux to a receiver coil in the electronic device via a magnetic flux pathway.

Claims:
What is claimed is: 
     
       1. A wireless charging device comprising:
 a housing having a charging surface and defining a cavity within the wireless charging device; 
 a base disposed within the cavity and comprising ferrite material, the base having a plurality of pillars extending away from the base towards the charging surface, the plurality of pillars including a first pillar and a second pillar spaced apart from one another; and 
 a plurality of solenoids including a first solenoid wrapped around the first pillar such that the first solenoid is in contact with the first pillar along the length of the first solenoid and a second solenoid wrapped around the second pillar such that the second solenoid is in contact with the second pillar along the length of the second solenoid thereby forming a transmitter coil configured to direct magnetic flux through the charging surface. 
 
     
     
       2. The wireless charging device of  claim 1 , wherein the first and second solenoids are electrically coupled in series. 
     
     
       3. The wireless charging device of  claim 1 , wherein the plurality of pillars further includes a third pillar positioned between the first and second pillars, the plurality of solenoids further includes a third solenoid wrapped around the third pillar, and
 wherein the first and second solenoids are wrapped in a first direction around the respective first and second pillars and the third solenoid is wrapped around the third pillar in a second direction. 
 
     
     
       4. The wireless charging device of  claim 1 , wherein the first and second solenoids are in an opposing electrical relationship. 
     
     
       5. The wireless charging device of  claim 1 , wherein the first and second solenoids are independently controllable. 
     
     
       6. The wireless charging device of  claim 1 , wherein the plurality of pillars is evenly spaced apart and arranged radially around a center point of the base. 
     
     
       7. The wireless charging device of  claim 6 , wherein the first pillar has a flat interior face oriented towards the center point of the base and an opposing curved exterior face. 
     
     
       8. The wireless charging device of  claim 1 , further comprising third and fourth solenoids wrapped around respective third and fourth pillars, wherein the first, second, third, and fourth pillars are arranged radially around a center point of the base and evenly spaced apart. 
     
     
       9. The wireless charging device of  claim 8 , wherein the first, second, third and fourth solenoids are independently controllable. 
     
     
       10. A wireless charging device comprising:
 a housing having a charging surface and defining a cavity within the wireless charging device; 
 a base disposed within the cavity and comprising ferrite material, the base having a plurality of pillars including a first pillar and a second pillar, the first pillar extending away from the base towards the charging surface, the plurality of pillars spaced apart from one another; and 
 a plurality of solenoids including a first solenoid wrapped around the first pillar and a second solenoid wrapped around the second pillar thereby forming a transmitter coil configured to direct magnetic flux through the charging surface, 
 wherein the first solenoid is wrapped around the first pillar in a first direction and the second solenoid is wrapped around the second pillar in a second direction. 
 
     
     
       11. An electronic device comprising:
 a housing defining a recess within the electronic device; 
 a base disposed within the recess and comprising ferrite material, the base having first and second pillars extending away from the base and spaced apart from one another and arranged radially around a center point of the base; and 
 a receiver coil configured to receive magnetic flux, the receiver coil comprising first and second solenoids wrapped around the respective first and second pillars such that the first solenoid is in contact with the first pillar along the length of the first solenoid and the second solenoid is in contact with the second pillar along the length of the second solenoid. 
 
     
     
       12. The electronic device of  claim 11 , wherein the base has a third pillar positioned between the first and second pillars and the receiver coil further comprises a third solenoid wrapped around the third pillar, and
 wherein the first and second solenoids are wrapped around the respective first and second pillars in a first direction and the third solenoid is wrapped around the third pillar in a second direction. 
 
     
     
       13. The electronic device of  claim 12 , wherein the first, second, and third solenoids are electrically coupled in series. 
     
     
       14. The electronic device of  claim 11 , wherein the first pillar has a curved interior face oriented toward the center point of the base and an opposing curved exterior face. 
     
     
       15. An electronic device comprising:
 a housing defining a recess within the electronic device; 
 a base disposed within the recess and comprising ferrite material, the base having first and second pillars, the first pillar extending away from the base, and the first and second pillars spaced apart from one another and arranged radially around a center point of the base; and 
 a receiver coil configured to receive magnetic flux, the receiver coil comprising first and second solenoids wrapped around the respective first and second pillars, 
 wherein the first solenoid is wrapped around the first pillar in a first direction and the second solenoid is wrapped around the second pillar in a second direction. 
 
     
     
       16. A wireless charging system comprising:
 an electronic device comprising a casing defining a recess within the electronic device; a receiver base disposed within the recess and comprising ferrite material, the receiver base having first and second receiver pillars extending away from the receiver base and spaced apart from one another and arranged radially around a center point of the receiver base; and a receiver coil configured to receive magnetic flux, the receiver coil comprising first and second receiver solenoids wrapped around the respective first and second pillars; and 
 a wireless charging device comprising a housing having a charging surface configured to receive the electronic device and defining a cavity within the wireless charging device; a transmitter base disposed within the cavity and comprising ferrite material, the transmitter base having a plurality of transmitter pillars extending away from the transmitter base towards the charging surface, the plurality of transmitter pillars including a first transmitter pillar and a second transmitter pillar spaced apart from one another; and a plurality of solenoids including a first transmitter solenoid wrapped around the first pillar such that the first transmitter solenoid is in contact with the first pillar along the length of the first transmitter solenoid and a second transmitter solenoid wrapped around the second pillar such that the second transmitter solenoid is in contact with the second pillar along the length of the second transmitter solenoid thereby forming a transmitter coil configured to direct magnetic flux through the charging surface. 
 
     
     
       17. The wireless charging system of  claim 16 , wherein the transmitter coil further comprises a third transmitter solenoid wrapped around a third pillar of the plurality of transmitter pillars. 
     
     
       18. The wireless charging system of  claim 17 , wherein the transmitter coil further comprises a fourth transmitter solenoid wrapped around a fourth pillar of the plurality of transmitter pillars, and wherein the transmitter solenoids are independently controllable. 
     
     
       19. The wireless charging system of  claim 18 , wherein the first, second, third, and fourth transmitter solenoids are arranged radially around a center point of the transmitter base and evenly spaced apart. 
     
     
       20. The wireless charging system of  claim 16 , wherein the first transmitter solenoid and the first receiver solenoid are in an opposing electrical relationship and the second transmitter solenoid and the second receiver solenoid are in an opposing electrical relationship.

Description:
FIELD 
     The described embodiments relate generally to inductive charging. More particularly, the present embodiments are directed towards inductive chargers with solenoids shaped for improved efficiency. 
     BACKGROUND OF THE INVENTION 
     Electronic devices, such as smart phones, tablet computers, laptop computers, smart watches, wearable devices, and the like can be powered by one or more internal batteries. Through use, the batteries can lose charge, requiring periodic recharging. Some electronic devices include circuitry that enables the batteries to be charged by connecting them to a power source via a physical cable. Other electronic devices include circuitry that enables the batteries to be recharged wirelessly, for example, by placing the electronic device on a wireless charger and inductively transferring power from a transmitter coil in the wireless charger to a receiver coil in the electronic device. 
     During wireless charging, magnetic flux is typically generated by the transmitter coil in the wireless charger and used by the receiver coil in the electronic device to generate electric current used, for example, to charge a battery contained within the electronic device. When traveling from the transmitter coil in the wireless charger, the magnetic flux can interact with components in the wireless charger and wireless device. The interaction between the magnetic flux and the components can reduce the magnetic flux that reaches the receiver coil in the electronic device, which in turn reduces the electric current generated by the receiver coil in the electronic device. The reduction of electric current can undesirably increase the charging time of the batteries in the electronic device and reduce the efficiency of the wireless charging system. 
     BRIEF SUMMARY OF THE INVENTION 
     This disclosure describes various embodiments that relate to inductive charging systems having improved efficiency. The inductive charging systems can include a wireless charger with a transmitter coil and an electronic device with a receiver coil. In various embodiments, the transmitter coil and/or the receiver coil can include features for directing magnetic flux from the wireless charger to the electronic device. For example, the transmitter coil can include a solenoidal structure with solenoids arranged in a pattern. The solenoidal structure can direct the magnetic flux along a pathway from a first solenoid to the electronic device and back into a second solenoid. Directing the magnetic flux along a pathway can reduce the amount of flux that is lost due to the magnetic flux interacting with components in the wireless charger and/or electronic device. Reducing the amount of magnetic flux that is lost can increase the efficiency of the system and reduce the charging time required to charge the electronic device. Directing the magnetic flux along the pathway can additionally or alternatively allow for a reduction in the size of the transmitter coil and/or the receiver coil that is used to charge the electronic device. For example, the size of the transmitter coil and/or the receiver coil can be smaller than the coils used in a traditional charging system. 
     In various embodiments described herein, a wireless charging system can include a wireless charger and an electronic device. The wireless charger can include a cable extending between a connector and a wireless charging assembly. A DC-to-AC converter for converting a DC power signal to AC+ and AC− signals may be disposed in the connector and/or the wireless charging assembly. The cable can include wires for transmitting the AC+, AC−, and data signals from the connector to the wireless charging assembly. The wireless charging assembly can include a housing encasing a transmitter coil with features for directing magnetic flux from the charging assembly to the electronic device. The electronic device can include a receiver coil for receiving the magnetic flux and converting the flux to an electric current for charging a battery in the electronic device. 
     A wireless charging device is disclosed and includes the following: a housing having a charging surface and defining a cavity within the wireless charging device; a base disposed within the cavity and comprising ferrite material, the base having a plurality of pillars extending away from the base towards the charging surface, the plurality of pillars including at least a first pillar and a second pillar spaced apart from one another; and a plurality of solenoids including at least a first solenoid wrapped around the first pillar and a second solenoid wrapped around the second pillar thereby forming a transmitter coil configured to direct magnetic flux through the charging surface. 
     An electronic device is disclosed and includes the following: a housing defining a recess within the electronic device; a base disposed within the recess and comprising ferrite material, the base having first and second pillars extending away from the base and spaced apart from one another and arranged radially around a center point of the base; and a receiver coil configured to receive magnetic flux, the receiver coil comprising first and second solenoids wrapped around the respective first and second pillars. 
     A wireless charging system is disclosed and includes the following: an electronic device comprising a casing defining a recess within the electronic device; a receiver base disposed within the recess and comprising ferrite material, the receiver base having first and second receiver pillars extending away from the receiver base and spaced apart from one another and arranged radially around a center point of the receiver base; and a receiver coil configured to receive magnetic flux, the receiver coil comprising first and second receiver solenoids wrapped around the respective first and second pillars; and a wireless charging device comprising a housing having a charging surface configured to receive the electronic device and defining a cavity within the wireless charging device; a transmitter base disposed within the cavity and comprising ferrite material, the transmitter base having a plurality of transmitter pillars extending away from the transmitter base towards the charging surface, the plurality of transmitter pillars including at least a first transmitter pillar and a second transmitter pillar spaced apart from one another; and a plurality of solenoids including at least a first transmitter solenoid wrapped around the first pillar and a second transmitter solenoid wrapped around the second pillar thereby forming a transmitter coil configured to direct magnetic flux through the charging surface. 
     To better understand the nature and advantages of the present invention, reference should be made to the following description and the accompanying figures. It is to be understood, however, that each of the figures is provided for the purpose of illustration only and is not intended as a definition of the limits of the scope of the present invention. Also, as a general rule, and unless it is evident to the contrary from the description, where elements in different figures use identical reference numbers, the elements are generally either identical or at least similar in function or purpose. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a simplified illustration of a previously known wireless charging system including an electronic device and a wireless charger; 
         FIG. 1B  is the known charging system of  FIG. 1  with the magnetic flux pathway shown according to some embodiments of the present invention; 
         FIG. 2A  is a simplified illustration of a wireless charging system including an electronic device and a wireless charger according to some embodiments of the present invention; 
         FIG. 2B  is the charging system of  FIG. 2  with the magnetic flux pathway shown according to some embodiments of the present invention; 
         FIG. 3A  is an illustration of an exploded view of an example electronic device that can be included in particular embodiments of the wireless charging system of  FIG. 2  according to some embodiments of the present invention; 
         FIG. 3B  is an illustration of a receiver coil that can be included in particular embodiments of the electronic device of  FIG. 3A  according to some embodiments of the present invention; 
         FIG. 4A  is an illustration of an exploded view of an example wireless charger that can be included in particular embodiments of the wireless charging system of  FIG. 2A  according to some embodiments of the present invention; 
         FIG. 4B  is an illustration of a transmitter coil that can be included in particular embodiments of the wireless charger of  FIG. 4A  according to some embodiments of the present invention; 
         FIG. 5A  is an illustration of another wireless charger that can be included in particular embodiments of the wireless charging system of  FIG. 2A  according to some embodiments of the present invention; 
         FIG. 5B  is an illustration of an example transmitter coil that can be included in particular embodiments of the wireless charging system of  FIG. 5A  according to some embodiments of the present invention; 
         FIG. 6  is an example transmitter coil that can be included in particular embodiments of the wireless charging system of  FIG. 2A  according to some embodiments of the present invention; and 
         FIGS. 7A and 7B  are example charging cables that can be included in particular embodiments of the wireless charging system of  FIG. 2A  according to some embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A wireless charging system typically includes an electronic device positionable on a wireless charger. The wireless charger can include a housing with a charging surface for receiving the electronic device and a variety of components disposed within the housing, including a transmitter coil. The transmitter coil can generate and induct magnetic flux across the charging surface to the electronic device. The electronic device can include a receiver coil for receiving the magnetic flux and generating electrical current used to charge batteries contained within the electronic device. Some of the magnetic flux generated by the transmitter coil can be lost due to the interaction of the magnetic flux with components contained within the wireless charger and/or the electronic device. The lost flux reduces the amount of electric current that can be generated by the electronic device, reducing the efficiency of the charging system and increasing the charging time of the electronic device. 
     Various embodiments of the invention provide a solution by using transmitter and/or receiver coils with features for directing the path of magnetic flux, reducing the amount of magnetic flux lost to components within the electronic device and/or the wireless charger. For example, in some embodiments the transmitter coil and/or the receiver coil includes solenoids positioned in a pattern for directing the magnetic flux. The magnetic flux can flow in a pathway from a first solenoid of the transmitter coil, through the receiver coil of the electronic device, and back to the transmitter coil via a second solenoid. The magnetic flux pathway can reduce the amount of magnetic flux that is lost to components of the electronic device and/or the wireless charger. This in turn can increase the efficiency of the charging system and reduce the charging time of the electronic device. The magnetic flux pathway can additionally or alternatively allow for a reduction of the size of the transmitter coil and/or the receiver coil used to charge the electronic device. 
     These and other embodiments are discussed below with references to  FIGS. 1-7 ; however, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes only and should not be construed as limiting. 
       FIG. 1A  is a simplified illustration of a previously known wireless charging system  100  including an electronic device  102  and a wireless charger  106 . The wireless charger  106  includes a transmitter coil  108  and electronic circuitry  110  disposed within a housing  112 . Transmitter coil  108  is disposed adjacent to a charging surface  114  that can be a portion of an exterior surface of housing  112 . Electronic circuitry  110  provides power to the transmitter coil and includes a DC-to-AC converter that converts a DC current received via a cable  118  from an external source (e.g., a USB connector, not shown, that provides a 5 volt DC current to the wireless charger  106 ) to an AC current. The AC current can be supplied to the transmitter coil  108 , which generates magnetic flux, for example a time-varying electromagnetic field, that is inducted across the charging surface and can induce an electric current within a receiver coil  104  contained within an electronic device  102  when the electronic device is positioned on or adjacent to charging surface  114 . The electronic device  102  can then use the induced current, for example, to recharge an internal battery. 
       FIG. 1B  is the known charging system of  FIG. 1  with the magnetic flux  116  shown. The transmitter coil  108  and/or the receiver coil  104  can have a circular or oval shape that inducts the electronic flux from the transmitter coil to the receiver coil. The magnetic flux  116  can be inducted to the receiver coil  104  in a circular pattern, such that the magnetic flux flows from the interior of the transmitter coil  108  through the receiver coil  104  and back to the exterior of the transmitter coil. Components positioned near the transmitter coil  108  and/or the receiver coil  104  can interfere with the magnetic flux  116 , reducing the amount of magnetic flux that travels from the transmitter coil to the receiver coil. The reduction in the magnetic flux  116  can in turn reduce the current in the receiver coil  104  and the efficiency of the wireless charging system  100 , increasing the time required to charge the batteries of the electronic device  102 . 
     Turning now to  FIG. 2A , a charging system  200  including an electronic device  202  and a wireless charger  206  according to some embodiments of the present invention is shown. The wireless charger  206  can include a housing  212 , including a charging surface  214 , surrounding a transmitter coil  208 . The transmitter coil  208  can receive power from a cable  228  and generate magnetic flux  216 . The magnetic flux  216  can be generated according to Oersted&#39;s law. The transmitter coil  208  can include a base of material and one or more features to aid in generating and/or guiding the magnetic flux. For example, the transmitter coil  208  can include a base of ferrite and/or solenoids formed with copper wire wound around one or more columns of ferrite. In various embodiments, the solenoids can be spaced apart from one another and arranged in a pattern for directing the magnetic flux. For example, the transmitter coil  208  can include multiple solenoids spaced apart from one another and arranged in a circular pattern. In various embodiments, the transmitter coil  208  can include solenoids spaced 90 degrees apart. 
     The wireless charger  206  can be connected to a connector  218  via a cable  228 . The connector  218  can receive power from a power source and the cable  228  can transfer the power from the connector to the wireless charger  206 . In some embodiments, the connector  218  can include electronic circuitry  210  that converts DC current to AC current. The wireless charger  206  can include a transmitter coil  208  disposed within the housing  212  and positioned adjacent to a charging surface  214 . The transmitter coil  208  can receive the power from the cable  228  and generate magnetic flux (e.g., a time-varying electromagnetic field). The magnetic flux can be inducted by the transmitter coil  208  across the charging surface  214  to the electronic device  202  positioned adjacent to the charging surface (e.g., a portion of the electronic device contacting the charging surface). 
     The connector  218  can be electrically coupled with a power source to receive electric current. In some embodiments, the connector  218  can be a male plug connector that can be inserted into a corresponding female connector in an AC-to-DC adapter, such as an adapter that can be plugged into a standard AC wall outlet. For example, in some embodiments, connector  218  can be a type A or a type C Universal Serial Bus (USB) connector. The connector  218  can include a housing  220  that encases and protects various internal components of the connector  218 . The connector  218  can receive a DC current from a power source via one or more electrical contacts  222 . The contacts  222  can transmit the electric current from the power source to electronic circuitry  210 . In various embodiments, the electronic circuitry  210  is disposed within housing  220 , however, the electronic circuitry may be disposed within the wireless charger  206 . The electronic circuitry  210  can include, among other components, a DC-to-AC converter that can receive a DC current from the power source and convert the DC current to an AC current that can be supplied to wireless charger  206  via cable  228 . The contacts  222  can be arranged according to a standardized pinout (e.g., USB-A, USB-B, USB-C, etc.) that matches the pinout of the contacts in the power source. In some embodiments, the contacts  222  can include one or more contacts for receiving and/or transmitting data in addition to receiving power. 
     The DC-to-AC converter within the electronic circuitry  210  can receive the DC electric current from the power source via the contacts  222  and convert it to an AC+ current and an AC− current. The DC-to-AC converter can be a variety of appropriate chips or circuitry that converts a DC signal to an AC signal. In various embodiments, and as non-limiting examples, the converter can be part of an ASIC, can be within a microcontroller or other microprocessor chip or can be made from various discrete components. In some embodiments, the electronic circuitry  210  can include a Main Logic Board (MLB) and/or a Printed Circuit Board Assembly (PCBA) that has a first set of bonding pads that can be electrically coupled to the contacts  222  and a second set of bonding pads that can be coupled to wires within cable  228 . The DC-to-AC converter can be mounted to the MLB and electrical traces on the MLB can couple an input of the DC-to-AC converter to a bonding pad in the first set of bonding pads that is coupled to one of the contacts  222  that receives the DC current and can couple outputs of the converter to bonding pads in the second set of bonding pads on the MLB. 
     The electronic device  202  can include a housing  226  encompassing the receiver coil  204 . The receiver coil  204  can be positioned adjacent to charging surface  214  to receive the magnetic flux  216  generated by the transmitter coil  208  and generate electric. The electric current can be used, for example, to charge a battery contained within the electronic device  202 . The receiver coil  204  can be or include wire formed into one or more shapes. For example, the receiver coil  204  can include one or more solenoids formed by wires wrapped around columns of material. The columns can be or include ferrite or a similar material that can increase the field strength of the magnetic flux received from the wireless charger  206 . 
     Turning to  FIG. 2B , a detailed cross-section of the charging system  200  and the electronic device  202  is shown according to some embodiments of the present invention. Magnetic flux  216  can flow along a magnetic pathway (e.g., a magnetic circuit) from the transmitter coil  208  across the charging surface  214  to the receiver coil  204 . The transmitter coil  208  and/or the receiver coil  204  can include features to direct the magnetic flux along the pathway. For example, the transmitter coil  208  and/or the receiver coil  204  can include solenoids for generating and/or directing the magnetic flux. The magnetic flux  216  can be inducted from a first solenoid  230 A of the transmitter coil  208  to a first solenoid  232 A of the receiver coil  204 . The magnetic flux  216  can flow through the receiver coil  204 , for example around the arc of the receiver coil, to a second solenoid  232 B of the receiver coil. In various embodiments, the magnetic flux  216  can pass through a third solenoid  232 C positioned between the first and second solenoids  232 A,  232 B. The magnetic flux  216  can flow from the second solenoid  232 B of the receiver coil  204  to a second solenoid  230 B of the transmitter coil  208 . 
     The pathway of the magnetic flux  216  can prevent and/or reduce magnetic flux from being lost due to interaction of the magnetic flux with components in the electronic device  202  and/or the wireless charger  206 . As shown in  FIG. 1B , the magnetic flux  116  does not have a magnetic pathway and flows through the air. This allows the magnetic flux  116  to interact with components that may be positioned near the transmitter coil  108  and the receiver coil  104 , resulting in a loss of magnetic flux  116  and reducing the amount of magnetic flux that reaches the receiver coil. In contrast,  FIG. 2B  includes a magnetic pathway with a lower magnetic reluctance than the surrounding air. The lower magnetic reluctance causes the magnetic flux  216  to travel along the magnetic pathway away from components that may be positioned in the surrounding environment. This in turn increases the magnetic flux  216  flowing through the receiver coil  204  and decreasing the magnetic flux lost to the surrounding environment. Increasing the magnetic flux  216  flowing through the receiver coil  204  can increase the electrical current generated by the receiver coil and reduce inefficiency in the system. The increase in electrical current generation can, for example, reduce the charge time of the electronic device  202  positioned on the charging system  200 . Additionally or alternatively, increasing the efficiency of the system can allow for a reduction in the size of the transmitter coil  208  and/or the receiver coil  204  that is used in the charging system  200  without increasing the charge time of the electronic device  202 . 
     In some embodiments, the transmitter coil  208  can be electrically connected with control circuitry  224  for controlling the operation of the transmitter coil  208 . The control circuitry  224  can, for example, turn on and off the solenoids of the transmitter coil  208 . For example, solenoids can be turned on in pairs to direct the flow of the magnetic flux  216 . The control circuitry  224  can be or include a MLB and/or a PCBA. The control circuitry  224  can be connected with the cable  228  to receive power and data from the connector  218  and/or the electronic circuitry  210 . The control circuitry  224  can be connected to one or more solenoids. The control circuitry  224  can control the solenoids to change the polarity of the solenoids to direct the magnetic flux  216  through the receiver coil  204 . For example, a first solenoid can have a positive charge and an opposing second solenoid can have a negative charge, directing the magnetic flux  216  from the positive solenoid through the receiver coil  204  to the negative solenoid. 
     In various embodiments described herein, the shape and/or composition of the receiver coil  204  can direct the magnetic flux along a pathway at least partially defined by the receiver coil. For example,  FIGS. 3A and 3B  illustrate an example receiver coil  204  that can be included in particular embodiments of the charging system  200  of  FIG. 2A  according to some embodiments of the present invention.  FIG. 3A  is an illustration of an exploded view of an example electronic device  202  that includes a receiver coil  204  positioned within a housing  226 . The housing  226  can include one or more pieces that can be assembled to surround the receiver coil  204 . 
     As shown in  FIG. 3B , the receiver coil  204  can be sized and shaped to fit within the housing  226 . In various embodiments, the receiver coil  204  may be shaped to avoid other components positioned in the interior of the housing  226 . For example, the receiver coil  204  may be shaped to fit around an alignment component positioned within the housing  226 . The receiver coil  204  can include a base  302  and one or more solenoids  304 . The solenoids  304  can include a central pillar, for example, a central pillar including ferrite. One or more wires can be wound around the central pillar of the solenoids  304 . The solenoids can be electrically connected in series to form a continuous electrical pathway. In various embodiments, the receiver coil  204  can include three solenoids (e.g.,  304 A,  304 B, and  306 ). The base  302  can be sized and shaped to fit the solenoids  304 A,  304 B, and  306 . For example, the base  302  can be shaped in an arc (e.g., an arc having a horseshoe shape). The solenoids  304  can be positioned at various positions around the arc. In various embodiments, the base  302  can be or include ferrite and/or a similar material to enhance the induction of magnetic flux from the transmitter coil  208 . 
     The solenoids  304 A,  304 B, and  306  can be positioned in a pattern around the base  302 . For example, when the base  302  is shaped in an arc, a first solenoid  304 A can be positioned at one end of the arc, a second solenoid  304 B can be positioned at a second end of the arc, and a third solenoid  306  can be positioned in a middle portion of the arc between the first and second solenoids. In various embodiments, the base  302  can include one or more sections that are thicker than other sections. These thicker sections can have wire wound around the base  302  to form one or more solenoids  304 . For example, the third solenoid  306  can be formed using wire wound around a thicker portion of the base  302 . 
     In various embodiments, one or more of the solenoids  304  can have a curved shape that is the same or similar to the curvature of the base  302 . For example, the first solenoid  304 A can have an interior face and an opposing exterior face, one or both of which is curved. The interior face can be curved similar to or the same as the curvature of the base  302 . The solenoids  304  having one or more curved surfaces can increase the amount of magnetic flux received from the transmitter coil  208 . In some embodiments, the interior face can be a flat face and the exterior face can have a curvature that is similar to the curvature of the base. 
     In further embodiments, one or more of the solenoids  304  can be or include a pillar at least partially surrounded by a wire. For example, the solenoids  304  can include a central pillar made of ferrite and/or a similar material. The wire can be wound around at least a portion of the exterior of the central pillar. For example, the wire can be wound to cover a sidewall of the pillar from the base  302  to the top of the sidewall. The solenoids  304  can be connected in series, for example, with a single wire wound around the solenoids. However, multiple wires may be used (e.g., a wire for each solenoid) and connected in series via a pad or a conductive trace. Connecting the solenoids  304  in series allows the solenoids to function as a single coil, creating a continuous magnetic pathway for the magnetic flux  216 . 
     The solenoids  304  can include wire wound in one or more directions. For example, solenoids  304 A,  304 B can be would in a horizontal orientation and solenoid  306  can be wound in a vertical orientation. The solenoids  304  may be wound in different directions to allow the electronic device  202  to be compatible with various charging systems  200 . For example, the solenoids  304 A and  304 B may be compatible with a first charging system and the solenoid  306  may be compatible with a second charging system. However, the solenoids  304  can be used together with a charging system  200  to maximize charging of the electronic device  202 . For example, the solenoids  304  can be arranged in a pattern with solenoid  306  positioned between solenoids  304 A and  304 B. The magnetic flux  216  can flow through all three solenoids, maximizing the electric current that is generated to charge the electronic device  202 . 
     Turning to  FIGS. 4A and 4B  an exploded view of a wireless charger  206  including a transmitter coil  208  is shown according to some embodiments of the present invention. The wireless charger  206  can include housing  212  with charging surface  214 . The housing  212  and/or the charging surface  214  can be separate pieces, however, the housing and charging surface  214  may be formed from a single piece of material. The housing  212  and/or the charging surface  214  can form an interior cavity to surround the components of the wireless charger  206 . For example, the housing  212  can surround the transmitter coil  208  and control circuitry  224  positioned within the wireless charger  206 . 
     In various embodiments, the wireless charger  206  can include one or more aligning devices  402  that can be used to align the electronic device  202  with the wireless charger  206 . The aligning devices  402  can align the receiver coil of the electronic device  202  with the transmitter coil  208  of the charging system  200  to maximize the charging of the electronic device. For example, the aligning devices  402  can align the receiver coil  204  of the electronic device  202  in any one of four positions. In any of these positions, the transmitter coil  208  and the receiver coil  204  can be aligned and the flow of magnetic flux  216  between the two can be maximized. When the transmitter coil  208  and the receiver coil  204  are misaligned (e.g., between alignment positions) the flow of magnetic flux  216  may be decreased or stopped. The aligning devices  402  can be or include a magnet used to align the receiver coil  204  and the transmitter coil  208 . 
     As shown in more detail in  FIG. 4B , the transmitter coil  208  can include multiple solenoids  404  (e.g., solenoids  404 A,  404 B, and  404 C). The solenoids  404  can be arranged in a pattern and spaced apart at various positions around a base  406 . For example, the solenoids  404  can be arranged in a circular pattern. As shown, the base  406  has a circular shape, however, the base may be any suitable shape for receiving the solenoids  404 . The base  406  can be or include ferrite or a similar material that can boost the magnetic flux generated by the solenoids  404 . In various embodiments, the base  406  can have an open middle portion, however, the base  406  may be a solid disk of material. The solenoids  404  can be or include a central pillar made of ferrite and/or a similar material at least partially surrounded by wire. 
     The base  406  and/or the solenoids  404  can be electrically connected to the control circuitry  224  via wires  408 . The control circuitry  224  can individually control the solenoids  404 , for example, by turning them off or on. In various embodiments, two solenoids  404  can be activated to induct magnetic flux to the receiver coil  204 . For example, a first solenoid  404  can have a positive charge and a second solenoid can have a negative charge. The control circuitry  224  can activate the solenoids based on the orientation of the electronic device  202  relative to the wireless charger  206 . For example, in some embodiments the electronic device  202  can be positioned on the wireless charger  206  in one or more orientations. When the electronic device  202  is positioned on the charger  206  in a first orientation, the control circuitry  224  can activate the first solenoid  404 A and the third solenoid  404 C. When the position of the electronic device  202  is changed (e.g., the electronic device is rotated) the control circuitry  224  can activate the second solenoid  404 B and the third solenoid  404 C. The wireless charger  206  can determine the orientation of the electronic device  202  based on the magnetic flux  216  that is inducted to the electronic device from one or more of the solenoids  404 . For example, the control circuitry  224  can pulse magnetic flux  216  to determine the orientation of the electronic device  202 . In various embodiments, the control circuitry  224  can turn on and off the solenoids  404 A,  404 B,  404 C to optimize the magnetic flux that is inducted to the receiver coil  204 . For example, when the first solenoid  304 A of the receiver coil  204  is positioned above the third solenoid  404 C of the transmitter coil and the second solenoid  304 B of the receiver coil is positioned above the second solenoid  404 B, the control circuitry can activate the second and third solenoids  404 B,  404 C to induct magnetic flux from the third solenoid  404 C of the transmitter coil to the first solenoid of the receiver coil, flow around the arc of the receiver coil to the second solenoid  304 B of the receiver coil, and down into the second solenoid  404 B of the transmitter coil. In further embodiments, all of the solenoids  404 A,  404 B,  404 C can be used to induct magnetic flux to the receiver coil  204 . For example, while the second and third solenoids  404 B and  404 C induct magnetic flux through the first and second solenoids  304 A,  304 B of the receiver coil  204 , the first solenoid  404 A of the transmitter coil  208  can induct magnetic flux to the third solenoid  306  of the receiver coil  204 . 
       FIG. 5A  is an illustration of another example wireless charger  206  that can be included in particular embodiments of the charging system  200  of  FIG. 2A  according to some embodiments of the present invention. The wireless charger  206  can include housing  212  and charging surface  214  surrounding transmitter coil  208 . The housing  212  and/or the charging surface  214  can include features for aligning the receiver coil  204  and the transmitter coil  208 . For example, the housing  212  can include a shelf  502  that allows the electronic device  202  to be positioned in an orientation for receiving the magnetic flux from the transmitter coil  208 . In various embodiments, the centers of the receiver coil  204  and the transmitter coil  208  may be slightly offset from one another when the electronic device  202  is positioned on the wireless charger  206 . The receiver coil  204  aligned with the transmitter coil  208  can reduce the number of solenoids  404  needed to induct the magnetic flux from the transmitter coil  208  to the receiver coil  204 . For example, the receiver coil  204  can be aligned with the transmitter coil  208  as a mirror image of the transmitter coil  208  (e.g., the solenoids and the base arcs align). The transmitter coil  208  can include multiple solenoids  504 . The solenoids  504  can be the same as or similar to solenoids  404 . For example, the solenoids  504  can include a central pillar of ferrite surrounded by wire. A first solenoid  504 A of the transmitter coil  208  can induct magnetic flux to a first solenoid  304 A of the receiver coil  204 , around the arc of the base  302  to the second solenoid  304 B of the receiver coil  204 , and to the second solenoid  504 B of the transmitter coil  208 . Additionally or alternatively, a third solenoid  504 C of the transmitter coil  208  can induct magnetic flux to a third solenoid  306  of the receiver coil  204 . The solenoids  504  may be oriented in multiple directions to support various charging systems. For example, solenoids  504 A and  504 B may be oriented in a horizontal orientation and solenoids  504 C may be oriented in a vertical direction. Solenoids  504 A and  504 B may support charging using a first charging system and solenoid  504 C may support charging using a second charging system. In various embodiments, all of the solenoids  504 A,  504 B,  504 C may be used with one or more charging systems. 
       FIG. 6  illustrates another transmitter coil  208  that can be included in particular embodiments of the wireless charger  206  of  FIG. 2A  according to some embodiments of the present invention. The transmitter coil  208  can include four solenoids  604 A,  604 B,  604 C, and  604 D arranged in a circle. The solenoids can be evenly spaced apart (e.g., spaced 90 degrees apart), however, the solenoids may be spaced any suitable distance apart. The solenoids  604  can similar to or the same as solenoids  404  and/or  504 . The solenoids  604  can include a central ferrite pillar surrounded by wire. Control circuitry  224  can be electrically connected with the solenoids  604 A,  604 B,  604 C, and  604 D to control the solenoids. For example, the control circuitry  224  can activate two or more of the solenoids  604 A,  604 B,  604 C, and  604 D to induct the magnetic flux to the receiver coil  204 . For example, opposing solenoids (e.g.,  604 A and  604 C or  604 B and  604 D) can be activated to induct the magnetic flux. In various embodiments, adjacent solenoids (e.g.,  604 A and  604 B) can be activated to induct the flux. The control circuitry  224  can activate the solenoids  604 A,  604 B,  604 C, and  604 D based on the orientation of the receiver coil  204  relative to the wireless charger  206 . For example, as the orientation of the electronic device  202  changes, different solenoids  604 A,  604 B,  604 C, and  604 D can be energized to continue to induct the magnetic flux to the receiver coil  204 . 
     In various embodiments the solenoids  604  can be energized based on at least the position of the receiver coil  204 . For example, as the receiver coil  204  is rotated, different solenoids  604  can be energized. The solenoids  604  can be energized to direct magnetic flux around a portion of the receiver coil  204  along a magnetic flux pathway. 
     The transmitter coil  208  and/or the control circuitry  224  can receive power and/or data from cable  228  attached to the wireless charger  206 .  FIGS. 7A and 7B  are simplified cross section of cable  228  that can be incorporated into the wireless charger  206  of  FIG. 2A  according to some embodiments of the present invention. The cable  228  can include one or more wire bundles  702  for transmitting an AC current along the length of the cable  228 . The AC current can be split into an AC+ and an AC− current and transmitted through multiple wire bundles  702  to reduce the interference between the currents, for example a wire bundle  702 A can transmit the AC− signal and wire bundle  702 B can transmit an AC+ signal. The wire bundles  702  can be optimized to transmit the AC current at a specific frequency with minimal losses. In various embodiments, one or more wire bundles  702  can be used to create a common ground  716  between the connector  218  and the wireless charger  206 . 
     The wire bundles  702 A,  702 B can be or include on or more strands of wire  708  that transmit the AC signal surrounding a central fiber  710  for strengthening the wire bundles  702 . An electrically insulative sheath  712  can surround the wires  708  and prevent the wire bundles  702  from contacting one another. The diameter of each strand of wire  708  can be optimized to transmit the electric current at a specific frequency. For example, the diameter of each strand of wire  708  can be optimized to transmit the electric current at a frequency of about 380 hertz. The strands of wire  708  can be or include copper, copper alloy, or other electrically conductive material. The central fiber  710  can provide resistance against stresses applied to the wire bundles  702 . In some embodiments, the central fiber  710  can contain conductive material. The conductive material can transmit data along the length of the cable. Additionally or alternatively, one or more data cables  714  can be positioned in the cable  228  for transmission of data to and/or from the wireless charger  206  (e.g., the orientation of the electronic device  202  on the wireless charger  206 ). The data cables  714  can include strands of wire  708  for transmission of the data. The data cables  714  can positioned near the center of the cable  228 , such that, the wire bundles  702  are positioned between the data cables and protective layers  706 . 
     One or more strengthening members  704  can be included in the cable  228  to increase resistance against stresses put on the cable. The strengthening members  704  can include one or more fibers (e.g., carbon fibers) for strengthening the cable  228  against stresses in a specific direction. For example, the fibers can be used to strengthen the cable  228  against tensile stresses put on the cable. 
     One or more protective layers  706  can surround the wire bundles  702  and/or the strengthening members  704 . The one or more protective layers  706  can provide protection against electromagnetic interference, heat, and damage. The protective layers  706  can include, for example, an insulating jacket and/or a conductive shield. In some embodiments, one or more of the protective layers  706  can be an electrically conductive layer that is electrically coupled between an EMF shield in a connector and an EMF shield in a charging assembly. 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of specific embodiments are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the described embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings. 
     It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users.

Metadata:
Filing Date: 20200604
Publication Date: 20221011
Grant Date: 20221011
Priority Date: 20200604
Inventors: REN, SAINING
GRAHAM, Christopher S.
BRZEZINSKI, MAKIKO K.
DAYAL, ROHAN
THOMPSON, PAUL J.
Assignee: APPLE INC
CPC Classifications: [{"code": "H02J50/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/70", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0044", "inventive": false, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F38/14", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J50/402", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F38/14", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J7/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J50/70", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/402", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0042", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/255", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F38/14", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J7/02", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 78786190