PATENT DOCUMENT

Publication Number: US-10424962-B2
Application Number: US-201514871890-A
Country: US
Kind Code: B2

Title: Charging assembly for wireless power transfer

Abstract:
A charging assembly for wireless power transfer. In embodiments, the charging assembly comprises a housing, a cap structure, a ferrimagnetic sleeve, an inductive coil, a magnet, a printed circuit board assembly (PCBA), and a four-pin connector extending from a bottom surface of the PCBA. A ridge of the cap structure can be coupled to a lip of the housing. The housing can include a bottom housing surface having an aperture, and a sidewall extending between the bottom housing surface and the lip that extends outward from the sidewall along a perimeter of the housing parallel to the bottom housing surface. The four-pin connector can extend through the aperture of the housing. Some embodiments are directed to a charging device that incorporates the charging assembly.

Claims:
What is claimed is: 
     
       1. A wireless charging assembly comprising:
 a housing including a charging surface; 
 a ferrimagnetic sleeve disposed within the housing, the ferrimagnetic sleeve including first and second opposing faces, a first opening extending from the first face to the second face through the ferrimagnetic sleeve, and a recess surrounding the first opening and open at the first face; 
 an inductive coil disposed within the recess between the charging surface and the second face of the ferrimagnetic sleeve, the inductive coil being configured to wirelessly transmit power across the charging surface; 
 a printed circuit board (PCB) defining a second opening; and 
 a magnet surrounded by a casing disposed within the first and second openings, the casing having a flange member contacting the second face of the ferrimagnetic sleeve, interaction between the flange member and the second face of the ferrimagnetic sleeve preventing movement of the casing through the first opening and toward the charging surface. 
 
     
     
       2. The wireless charging assembly of  claim 1 , wherein the housing further includes a plurality of protrusions, each protrusion including a threaded screw hole configured to receive a screw or bolt. 
     
     
       3. The wireless charging assembly of  claim 1 , wherein the housing comprises a cap structure coupled to a housing component, the housing component including an exterior surface and a sidewall extending between the exterior surface and a lip that extends outward from the sidewall, the lip of the housing component being coupled to the cap structure. 
     
     
       4. The wireless charging assembly of  claim 1 ,
 wherein the ferrimagnetic sleeve is disposed between the PCBA and the charging surface. 
 
     
     
       5. The wireless charging assembly of  claim 4 , wherein the PCBA comprises one or more contact pads configured to receive wires from the inductive coil. 
     
     
       6. The wireless charging assembly of  claim 5  further comprising a guide element disposed in a notched portion of the ferrimagnetic sleeve, the guide element configured to guide the wires from the inductive coil to the one or more contact pads. 
     
     
       7. The wireless charging assembly of  claim 4 , further comprising:
 a connector attached to the PCBA and extending from a surface of the PCBA through an aperture defined by an exterior surface of the housing, the connector being electrically coupled to the inductive coil. 
 
     
     
       8. The wireless charging assembly of  claim 4 ,
 wherein the charging surface has a concave geometry. 
 
     
     
       9. The wireless charging assembly of  claim 8 , wherein the casing physically and electrically isolates the magnet from both the PCBA and the ferrimagnetic sleeve. 
     
     
       10. A wireless charging assembly, comprising:
 a housing including an exterior housing surface, a sidewall extending between the exterior housing surface and a lip that extends outward from the sidewall along a perimeter of the housing; 
 a cap structure having a charging surface and an interior-facing surface opposite the charging surface, the interior-facing surface coupled to the housing at the lip; 
 a ferrimagnetic sleeve disposed within the housing, the ferrimagnetic sleeve including first and second opposing faces, a central opening extending from the first face to the second face through the ferrimagnetic sleeve, and a recess surrounding the central opening and open at the first face; 
 an inductive coil disposed within the recess between the interior-facing surface and the second face of the ferrimagnetic sleeve, the inductive coil configured to wirelessly transmit power across the charging surface; and 
 a printed circuit board assembly (PCBA) disposed within the housing between the second face of the ferrimagnetic sleeve and the exterior housing surface, the PCBA defining a hollow portion; and 
 a magnet disposed within a casing disposed within both the central opening of the ferrimagnetic sleeve and the hollow portion of the PCBA, the casing having a flange member contacting the second face of the ferrimagnetic sleeve, wherein interaction between the flange member and the second face of the ferrimagnetic sleeve prevents movement of the casing closer to the interior-facing surface of the cap structure. 
 
     
     
       11. The wireless charging assembly of  claim 10 , wherein the exterior housing surface further includes a plurality of protrusions, each protrusion including a threaded screw hole configured to receive a screw or a bolt. 
     
     
       12. The wireless charging assembly of  claim 10  further comprising an adhesive material disposed between the cap structure and the housing. 
     
     
       13. The wireless charging assembly of  claim 10 , wherein the wireless charging assembly is substantially impermeable to liquids. 
     
     
       14. The wireless charging assembly of  claim 10  wherein the PCBA comprises one or more contact pads configured to receive wires from the inductive coil. 
     
     
       15. The wireless charging assembly of  claim 14  further comprising a guide element disposed in a notched portion of the ferrimagnetic sleeve, the guide element configured to guide the wires from the inductive coil to the one or more contact pads. 
     
     
       16. The wireless charging assembly of  claim 10 , wherein the charging surface has a concave geometry. 
     
     
       17. The wireless charging assembly of  claim 10 , wherein the casing physically and electrically isolates the magnet from both the PCBA and the ferrimagnetic sleeve.

Description:
FIELD 
     The present invention relates generally to a wireless charging assembly. More particularly, the present invention relates to a wireless charging assembly that can be used as a component in a charging device such as a charging station. 
     BACKGROUND 
     Mobile devices such as smart phones, tablets, smart watches, and the like can be configured for wireless charging. Such mobile devices are often sold along with a wireless charging device (e.g., a charging station) that is specifically configured for charging the mobile device and, in some instances, charging other devices made by the same manufacturer. 
     Some customers may prefer to use charging devices other than the charging station that comes with the mobile device at the time of purchase for a variety of reasons. Hence, there is a need to allow third-party manufacturers of charging devices such as docking stations to configure their charging devices for wireless charging of mobile devices that they themselves do not manufacture. In order for a third-party manufacturer&#39;s docking station to wirelessly charge such mobile devices, they may need a charging assembly compatible with both the docking station and the mobile device it is meant to charge. 
     Sometimes, third-party manufacturers also provide peripheral systems that utilize mobile devices and provide additional functionality, such as playing audio on speakers or video on a display device. These third-party manufacturers may wish to provide charging capabilities for mobile devices in such peripheral systems. In other words, they may wish to incorporate a charging device into the peripheral system. 
     Further, manufacturers of mobile devices may have a need for a modular wireless charging assembly that can be easily incorporated into different charging devices and peripheral systems also provided by the manufacturers of mobile devices. 
     SUMMARY 
     Some embodiments of the invention pertain to wireless charging assemblies with application in wireless charging devices. Other embodiments pertain to wireless charging devices including such wireless charging assemblies. The wireless charging assemblies in accordance with embodiments of the present invention can be used in charging device (such as third party charging devices), peripheral audio/video devices, and the like, but embodiments of the invention are not limited to such applications. 
     Some embodiments pertain to a wireless charging assembly comprising a housing, a cap structure, a ferrimagnetic sleeve, an inductive coil, a magnet, a printed circuit board assembly (PCBA), and a four-pin connector. The housing can include a bottom housing surface having an aperture, and a sidewall extending between the bottom housing surface and a lip that extends outward from the sidewall along a perimeter of the housing parallel to the bottom housing surface. 
     The cap structure can have a charging surface and a bottom cap surface opposite the charging surface. The bottom cap surface can include a ridge formed along a perimeter of the cap structure and can be coupled to the housing at the lip. In some embodiments, the bottom housing surface further can have a plurality of protrusions, each protrusion including a threaded screw hole configured to receive a screw or bolt. 
     The ferrimagnetic sleeve can be disposed within the housing. The ferrimagnetic sleeve can include first and second opposing faces, a central opening extending from the first face to the second face through the ferrimagnetic sleeve, and a recess surrounding the central opening and open at the first face. 
     The inductive coil can be disposed within the recess between the bottom cap surface and the second face of the ferrimagnetic sleeve. The inductive coil can be configured to wirelessly transmit power across the charging surface. 
     The magnet can be disposed within the central opening of the ferrimagnetic sleeve. The PCBA can be disposed within the housing between the second face of the ferrimagnetic sleeve and the bottom housing surface. The four-pin connector can be attached to (or part of) the PCBA and extend from a bottom surface of the PCBA through the aperture. The four-pin connector can be electrically coupled to the inductive coil. In some embodiments, the PCBA can comprise one or more contact pads configured to receive (and electrically couple to) wires from the inductive coil. In some embodiments, the PCBA can comprise wireless charging circuit elements. 
     The wireless charging assembly can further comprising an electromagnetic shield disposed between the bottom cap surface of the cap structure and the inductive coil. In some embodiments, the wireless charging assembly can further comprise an adhesive material disposed between the cap structure and the housing. In some embodiments, the wireless charging assembly is substantially impermeable to liquids. 
     In some embodiments, the wireless charging assembly can further comprising a guide element disposed in a notched portion of the ferrimagnetic sleeve. The guide element can be configured to guide the wires from the inductive coil to the one or more contact pads of the PCBA. 
     In some embodiments, the PCBA can include a hollow portion in which the magnet is disposed. The magnet can be separated from both the PCBA and the ferrimagnetic sleeve by a casing disposed around the magnet. 
     Some embodiments are directed to a charging device comprising a female connector configured to transmit power to a four-pin male connector, and a wireless charging assembly comprising a housing, a cap structure, a ferrimagnetic sleeve, an inductive coil, a magnet, a printed circuit board assembly (PCBA), and the male four-pin connector extending from the bottom surface of the PCBA. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which: 
         FIG. 1  is a top perspective view of a wireless charging assembly according to some embodiments. 
         FIG. 2  is a bottom perspective view of the wireless charging assembly according to some embodiments. 
         FIG. 3  is an illustration of an exploded view of the sub-components of the wireless charging assembly in a stack, according to some embodiments. 
         FIG. 4  is a simplified cross section of a portion of the wireless charging assembly including a ridge of the cap structure coupled to a lip of the housing, according to some embodiments. 
         FIG. 5  is a simplified cross-section of a charging device incorporating the wireless charging assembly, according to some embodiments. 
         FIGS. 6A-6C  illustrate three examples of charging devices incorporating the wireless charging assembly, according to embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to representative embodiments illustrated in the accompanying drawings. It should be understood that the following descriptions are not intended to limit the embodiments to one preferred embodiment. To the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims. 
     Some embodiments described pertain to a wireless charging assembly that can be incorporated into a charging device (e.g. a “dock”, “docking station”, a portable battery, or a “charger”). The charging device can include (or be electrically coupled to) a power source that can provide power to charging circuitry of the charging assembly through a four-pin connector. The charging assembly can be used to wirelessly transmit power to the charging circuitry (e.g., a receiver coil) of a mobile device such as a wearable device. The mobile device can use the transmitted power to charge its internal battery. In addition to wearables, other examples of mobile devices can include smart phones, media players, personal digital assistants, tablet computers, laptop computers, and the like. 
       FIG. 1  is a top perspective view of a wireless charging assembly  100  according to embodiments. As shown in  FIG. 1 , charging assembly  100  comprises a cap structure  110  and a housing  140 . Cap structure  110  and housing  140  can be in contact (or almost in contact separated by a thin layer of adhesive) along a rim region  120  on the outer perimeter. Cap structure  110  can include a charging surface  115  which can have a shape contoured to support the corresponding charging surface of a coupled mobile device during wireless charging. For example, in the example shown in  FIG. 1 , charging surface  115  has a non-planar (i.e. concave) shape that corresponds to a convex charging surface of a mobile device. It should be noted, however, that although charging surface  115  has been shown with the concave shape, embodiments the invention are not limited to such. In other embodiments, charging surface  115  can have any other shape such as a convex shape, wavy shape, a planar shape, or any other suitable shape. 
     As shown in  FIG. 1 , charging assembly  100  comprises a housing  140  including a bottom housing surface. Although not apparent from the top perspective shown in  FIG. 1 , housing  140  can include an aperture and, in some embodiments, a plurality of protrusions, each protrusion including a screw hole as described below with reference to  FIG. 2 . A small portion of one protrusion  130  is visible in  FIG. 1 . Housing  140  includes a sidewall with a cylindrical portion extending between the bottom housing surface. Housing  140  also includes a lip (or “flange”) that extends outward from the sidewall along a perimeter of the housing parallel to the bottom housing surface. Cap structure  110  can include a ridge along its parameter, the ridge being coupled to the lip of housing  140 . The lip of housing  140 , along with the parameter of cap structure  110  including the ridge, form rim region  120 . Rim region  120  is described in further detail below with reference to  FIG. 4 . Cap structure  110  can have a bottom cap surface opposite charging surface  115  (not apparent from  FIG. 1 ) and on which the ridge is disposed. In some embodiments, the ridge of cap structure  110  can be in physical contact with the lip of housing  140 . In other embodiments, the ridge of cap structure  110  can be coupled to the lip of housing  140  using a thin layer of adhesive such as epoxy or resin. 
     Although shown in  FIG. 1  as substantially cylindrical, charging assembly  100  can be formed in various shapes to match either a surface of the device-to-be-charged, or to fit a charging device, or both. For example, in embodiments, charging assembly  100  or charging surface  115  can be substantially cubic, triangular, spherical, etc. in shape. In embodiments, charging assembly  100  can be sized appropriately to the mobile device it is configured to charge. 
     Housing  140  and cap structure  110  can be made from a non-corrosive, chemically resistant, and inert material that can withstand mechanical and thermal stress. For example, housing  140  can be made from rigid materials such as a suitable metal, metal alloy, ceramic, plastic, or composite. In some embodiments, housing  140  can be made from a 300 series stainless steel, such as 304. Cap structure  110  can be made from any suitable ceramic, plastic, or composite. For example, in some embodiments, cap structure  110  can be made from a polycarbonate material. In embodiments, cap structure  110  and housing  140  can be coupled using an adhesive (e.g., a resin) such that charging assembly  100  is water and liquid resistant. 
       FIG. 2  is a bottom perspective view of wireless charging assembly  100 . As shown in  FIG. 2 , the ridge of cap structure  110  is coupled to a lip  220  of housing  140  at rim region  120 . Three protrusions  130  including screw holes are shown forming an equilateral triangle on a bottom surface of housing  140  in the illustrated embodiment, although protrusions  130  and their screw holes can be disposed in any suitable configuration and in any suitable number. Although not apparent from  FIG. 2 , the screw holes can be threaded on an inner surface to accommodate threaded screws, bolts, and the like. I 
     Protrusions  130  can comprise any suitable metal, metal alloy, ceramic, plastic, or composite. In some embodiments, protrusions  130  can comprise the same material as housing  140 . As shown in  FIG. 2 , protrusions  130  can protrude from the bottom surface of housing  140 . In some embodiments, protrusions  130  can be attached to housing  140  by means of an adhesive. In some other embodiments, protrusions  130  can be soldered onto housing  140 . In yet other embodiments, the bottom surface of housing  140  and protrusions  130  are constructed from the same piece of material such that housing  140  and protrusions  130  form a unitary body. Protrusions  130  can be used to physically couple charging assembly  100  to a charging device. In embodiments, this can be achieved by fastening screws through screw-holes lining inner portion of protrusions  130 . 
     In addition to or instead of restraining charging assembly  100  to a charging device using protrusions  130 , a surface of lip  220  of housing  140  can be used to secure charging assembly  100  to a charging device using a glue or other adhesive. More specifically, a surface of lip  220  can be adhered to a surface of a charging device. In some embodiments, charging assembly  100  can be secured to a charging device using an adhesive at the surface of lip  220  in addition to screws or bolts inserted into the screw holes of protrusions  130 . The size of lip  220  of housing  140  can be varied depending on the particular application, including and the external and/or internal surfaces of the charging device into which charging assembly  100  is incorporated. In some embodiments, where charging assembly  100  is secured to a charging device using adhesive, charging assembly  100  may not include protrusions  130  at the bottom of the housing. 
     As shown in  FIG. 2 , charging assembly  100  can include a four-pin connector  210 . In  FIG. 2 , four-pin connector  210  is a male connector than can be electrically coupled to a charging device so that power can be provided to charging assembly  100 . In some embodiments, four-pin connector  210  can be used to connect charging assembly  100  to a USB power supply. In embodiments, the four pins in four-pin connector  210  can correspond to USB plus, USB minus, power, and ground. In some embodiments, four-pin connector  210  can enable basic data transfer such as USB handoff in addition to power transfer. In some embodiments, four-pin connector  210  could be a debug header, where the USB plus and minus pins are data pins that can be used for debugging. 
     In some embodiments, four-pin connector  210  can be attached to a corresponding socketed female connector in a charging device. The female connector can be coupled to a source of power, such as a USB port (which in turn can derive power from a battery or power outlet) through a flexible cable. In some embodiments, four-pin connector  210  can be attached to a through-hole on a charging device printed circuit board (PCB) and soldered in place. In such embodiments, protrusions  130  can be used to attach housing  140  to the charging device PCB. Alternatively, the pins of four-pin connector  210  can be soldered directly to wires in a charging device that can eventually be connected to a source of power, such as a USB port. 
     In some embodiments, four-pin connector  210  can be attached to housing  140  at an aperture  215  with an adhesive, such as an epoxy resin. By sealing any empty space formed between the outer parameter of four-pin connector  210  and aperture  215 , charging assembly  100  can be further impermeable to liquids such as water. In some embodiments, four-pin connector  210  can be soldered to housing  140  in addition to, or in place of, sealing with an adhesive. 
       FIG. 3  is an illustration of an exploded view of the sub-components of wireless charging assembly  100  in a stack, according to some embodiments. In some embodiments, the sub-components except for cap structure  110  shown in  FIG. 3  can be disposed predominantly within housing  140  and covered by cap structure  110 . In some other embodiments, charging assembly  100  can contain more or less sub-components than those shown in  FIG. 3 . 
     Beginning from the top of  FIG. 3 , charging assembly  100  can comprise cap structure  110  with charging surface  115 , as explained previously. Cap structure  110  can also be made from any suitable metal, metal alloy, ceramic, plastic, or composite. For example, in some embodiments, cap structure  110  can be made from a polycarbonate material. Cap structure  110  can be cast, machined, stamped, or formed as otherwise desired. Cap structure  110  can be made aesthetically pleasing because in some embodiments, cap structure  110  can be the only visible part from charging assembly  100  in a final charging device. In embodiments, after charging assembly  100  is incorporated into a charging device such as a docking station, the top surface of cap structure  110  can be the only visible part charging assembly  100  to a user. 
     In some embodiments, charging assembly  100  can include an electromagnetic shield  305  below cap structure  110 . In embodiments, electromagnetic shield  305  can be a capacitive shield that helps to remove coupled noise between the charging system and the mobile device during a charging operation, or during the operation of a mobile device (for example, by touching a screen on the mobile device) when it is placed on charging surface  115 . Electromagnetic shield  305  can drown out some or all of the capacitive coupling that can occur between an inductive coil  315  of charging assembly  100  and an inductive receiver coil in a mobile device. Such capacitive coupling can otherwise lead to ground noise, especially on the mobile device side. In embodiments, electromagnetic shield  305  can be grounded to a common ground for charging assembly  100 . Housing  140  and other sub-components such as a Main Logic Board (MLB) on a Printed Circuit Board Assembly (PCBA)  360  can also be connected to the common ground. 
     Electromagnetic shield  305  can be made of a suitable thin, flexible, material in some embodiments. Electromagnetic shield  305  can comprise one or more layers including, for example, a dielectric layer, an adhesive layer, and a conductive layer. In other embodiments, electromagnetic shield  305  can be a conductive coating, for example deposited by Physical Vapor Deposition (PVD). In some examples, electromagnetic shield  305  can be an ink or a conductive Pressure Sensitive Adhesive. In some embodiments the total thickness of electromagnetic shield  305  can be of the order of 50 microns, including a conductive layer thickness of approximately 12 microns. Electromagnetic shield  305  can be attached to the ground by a ground connector  310 . Electromagnetic shield  305  may not be present in some embodiments. 
     As shown in  FIG. 3 , charging assembly  100  can include inductive coil  315  below electromagnetic shield  305 . Inductive coil  315  can be used to generate and transmit a time-varying electromagnetic field from, for example, an alternating current (AC) flowing through inductive coil  315 . This field can generate a corresponding time-varying current within an inductive receiver coil in a mobile device coupled to charging assembly  100  by way of electromagnetic induction (not shown in  FIG. 3 ). Thus, inductive coil  315  and the receiver coil can effectively form an electrical transformer. 
     In embodiments, inductive coil  315  can include one or more layers. In some embodiments, inductive coil  315  can be formed by patterning a multi-layer flexible structure comprising a layer of conductive material. In other embodiments, inductive coil  315  can be formed by winding an electrical conductive wire. In some embodiments, inductive coil  315  can be characterized by a three dimensional shape. The three-dimensional shape can be achieved, for example, by compression molding or vacuum forming of a substantially planar coil. 
     The conductive material in inductive coil  315  can comprise any suitable electrically conductive material including, but not limited to, metals (e.g. copper, gold, silver, etc.), alloys, semiconductors, conductive ceramics, conductive polymers, and the like. As shown in  FIG. 3 , inductive coil  315  can comprise lead wires  320 . Inductive coil  315  can optionally comprise insulating material such as polyimide, PET, and other thermoformable materials. In some embodiments, lead wires  320  can correspond to positive and negative signals and can be used to transmit a time-varying current through inductive coil  315 . As will be described in further detail below, lead wires  320  can be guided through a guide  345  and can make contact with contact pads  370  on PCBA  360 . 
     As shown in  FIG. 3 , charging assembly  100  can include a ferrimagnetic sleeve  325  disposed such that inductive coil  315  is located between ferrimagnetic sleeve  325  and cap structure  110 . Ferrimagnetic sleeve  325  can help direct the electromagnetic flux lines from inductive coil  315  to an inductive receiver coil in a charging mobile device. Ferrimagnetic sleeve  325  can also shield PCBA  360  from electromagnetic fields by providing a low magnetic loss path for the flux lines through ferrimagnetic sleeve  325 . Ferrimagnetic sleeve  325  can be comprised of ferrite material (ceramic material composed of iron oxide) or any other suitable ferrimagnetic material. In embodiments, ferrimagnetic sleeve  325  can be polymer based. 
     Ferrimagnetic sleeve  325  can include a first and second opposing faces, and a central opening  335 . As shown in  FIG. 3 , the first face of ferrimagnetic sleeve  325  is the top face and the second face is the bottom face. In embodiments such as those shown in  FIG. 3 , central opening  335  can be substantially concentric to electromagnetic shield  305  and inductive coil  315 . Ferrimagnetic sleeve  325  can also include a recess  340  open at the first face and surrounding central opening  335 . Inductive coil  315  can be disposed in recess  340  such that is it effectively located between the bottom cap surface and the bottom face of the ferrimagnetic sleeve  325 , as shown in  FIG. 3 . 
     In some embodiments, ferrimagnetic sleeve  325  can include a notched portion  330  as shown in  FIG. 3 . In such embodiments, wireless charging assembly  100  can include a guide element  345  disposed in notched portion  330 . Guide element  345  can comprise a plurality of holes or channels that can be used to guide wires from inductive coil  315  to one or more contact pads  370  on PCBA  360 . In embodiments where there is limited space inside charging assembly  100  (e.g., within housing  140 ), guide element  345  can help manage lead wires  320  from inductive coil  315  such that lead wires  320  do not splay and/or come into contact with certain sub-components of charging assembly  100 . 
     As shown in  FIG. 3 , charging assembly  100  can include a magnet  350  disposed at least partially within central opening  335  of ferrimagnetic sleeve  325 . In embodiments, magnet  350  can also extend into a hollow portion  365  of PCBA  360 . As shown in  FIG. 3 , magnet  350  can also be surrounded by a casing  355 . Casing  355  can be substantially conformal to magnet  350  and can isolate (e.g., physically and electrically) magnet  350  from both PCBA  360  and ferrimagnetic sleeve  325 . Magnet  350  can be used in conjunction with a corresponding magnet located in a mobile device to be charged to align the mobile device to charging assembly  100 . More particularly, magnet  350  can be used to align inductive coil  315  and an inductive receiver coil in the mobile device during a charging operation to maximize efficiency of charging. 
     As further shown in  FIG. 3 , charging assembly  100  can include PCBA  360  disposed within housing  140  between the second surface of ferrimagnetic sleeve  325  and the bottom housing surface. PCBA  360  can include power circuit elements for wireless charging. In some embodiments, PCBA  360  can comprise one or more contact pads  370 . Three contact pads are shown in  FIG. 3 : in one example, two contact pads can provide connection to the lead wires  320  (positive and negative) from inductive coil  315 , and one contact pad can provide connection (e.g., a ground) to electromagnetic shield  305 , thereby forming three service loops inside charging assembly  100 . 
     Although not apparent from  FIG. 3 , PCBA  360  includes a four-pin connector attached to and/or extending from a bottom surface of PCBA  360  opposite the surface comprising contact pads  370 . This four-pin connector can be a male four-pin connector such as four-pin connector  210  shown in  FIG. 2 . The male four-pin connector can extend through aperture  215  of housing  140 . In embodiments, the male four-pin connector can be attached to a power supply of a charging device into which charging assembly  100  is incorporated. 
     All the sub-components shown in  FIG. 3  can be assembled together and compressed to form the final charging assembly  100  as shown in  FIGS. 1 and 2 . Several sub-components, for example those sub-components shown in  FIG. 3  as above the PCBA, can be attached to the bottom cap surface of cap structure  110  with an adhesive such as a glue, Pressure Sensitive Adhesive (PSA), or the like. PCBA  360  can be conductively adhered to housing  140  (e.g., using a conductive PSA). As shown in  FIG. 2 , the four-pin connector can be sealed at aperture  215  by using an ultra-violet curing (UV) glue. The four-pin connector can be attached to the PCBA by soldering. Lead wires  320  of inductive coil  315  can be coupled (e.g., soldered) to contact pads  370  of PCBA  360 . Housing  140  can be filled with an adhesive such as resin over PCBA  360 . The resin can comprise, for example, epoxy, acrylic, polyimide, or other adhesives. Components above PCBA  360  in  FIG. 3  can be pushed down into housing  140  towards PCBA  360 . During the process, some of the resin is displaced such that it creeps up into the region between the ridge of cap structure  110  and lip  220  of housing  140 , thereby coupling cap structure  110  with housing  140 . 
     The various sub-components of charging assembly  100  can be sensitive to moisture and vibrations. In some embodiments, as summarized above, the various sub-components can be “potted” by a non-conductive adhesive material such as a resin. For example, a liquid settable epoxy can be used to fill, partly or wholly, any spaces between the sub-components, housing  140 , and the bottom cap surface of cap structure  110 . Such an encapsulated assembly can provide various advantages. For example, the a non-conductive adhesive material can offer substantial impermeability to liquids and resistance to shock and vibrations. 
       FIG. 4  is a simplified cross section of rim region  120  of wireless charging assembly  100 , including a ridge  430  of cap structure  110  and lip  220  of housing  140 , according to an embodiment. As described above, when components are pushed down into housing  140  towards PCBA  360 , some of the resin can be displaced such that it creeps up into the region between ridge  430  of cap structure  110  and lip  220  of housing  140 , thereby coupling cap structure  110  with housing  140 . When cured, the resin can bond cap structure  110  to housing  140  at surface contact  420 , thereby making the seal water and/or air tight. In some embodiments, the setting process can involve the application of heat and/or pressure. In some embodiments, a layer of adhesive can optionally also be applied on surface contact  420 , although other embodiments may not involve adhesive on surface contact  420 . 
       FIG. 5  is a simplified cross-section of wireless charging assembly  100  as used in a charging device  500 , according to an embodiment. For example, charging device  500  can be a dock, docking station, portable battery, charger, or the like. As shown in  FIG. 5 , charging device  500  can comprise a base unit  510 , charging assembly  100 , and a power source  520 . In some embodiments, base unit  510  can comprise an internal battery such that power can be supplied to four-pin connector  210  of charging assembly  100  without the need to maintain a continuous source of power from power source  520 . Although shown for one example configuration of base unit  510 , charging device  500  can be incorporated into any other suitable base unit having a different configuration and/or geometry, as will be explained with the non-limiting examples in  FIGS. 16A-C . 
     As shown in  FIG. 5 , charging assembly  100  can be secured to base unit  510  using protrusions  130  having screw-holes. In  FIG. 5 , two protrusions are visible in the cross-section. Screws  530  can be used to fasten charging assembly  100  to base unit  510 . Since charging assembly  100  is physically coupled to charging device  500  internally, protrusions  130  and screws may not be visible to a user of charging device  500 . In some embodiments, bolts can be used in place of or in addition to screws. In some embodiments, charging assembly  100  can additionally or instead be secured to base unit  510  of charging device  500  by means of an adhesive. 
     Four-pin male connector  210  of charging assembly  100  can be attached to a corresponding four-pin female connector  540  of charging device  200 . Although not apparent from  FIG. 5 , four-pin female connector  540  can be attached to power source  520  within base unit  510 . In some embodiments, power source  520  can be further connected to an outlet such as a wall outlet or USB port through a flexible cable. The flexible cable can include a conductor pair and a thermally conductive shield layer. In some embodiments, four-pin connector  210  can be attached to a through-hole on a printed circuit board (PCB) of base unit  510  of charging device  500  and soldered in place. Alternatively or additionally, the pins from four-pin connector  210  can be soldered directly to wires that can be connected to the PCB or other circuitry electrically coupled to power source  520 . In some embodiments, charging device  500  can include more than one of charging assembly  100  to accommodate a plurality of mobile devices for charging. 
     During a wireless power transfer operation from charging device  500  to a mobile device placed on charging surface  115 , the mobile device can activate circuitry associated with managing and distributing power received from the charging device. In some embodiments, the mobile device can communicate to charging device  500  via a wireless communication channel that the mobile device is ready to receive power. After receiving such a signal, the charging device can generate an alternating or switch current in inductive coil  315 , which in turn can induce a corresponding electrical current in the inductive receiver coil in the mobile device. The mobile device can use the received current to, for example, replenish the charge of one or more internal batteries. Although not apparent from  FIG. 5 , charging device  500  can also include a transceiver to communicate with the mobile device. In some embodiments, charging device  500  can vary or adjust dynamically characteristics of the transmitted power based on information received from the mobile device, or from an external source. 
       FIGS. 6A-C  are three examples of charging devices  600 ,  610 , and  620 , for charging a mobile device utilizing charging assembly  100 , according to embodiments. In embodiments, charging devices  600 ,  610 , and  620  can provide additional functionality apart from charging of mobile devices. For example, charging devices  600 ,  610 , and  620  can also play media content stored in the mobile device by way of a speaker and/or a video display. 
       FIG. 6A  is a simplified illustration of one example charging device  600  incorporating charging assembly  100 . As shown in  FIG. 6A , charging device  600  includes a base structure  604 . Pedestal structure  602  can be mounted on base structure  604 . Pedestal structure  602  can include charging assembly  100 , which can be secured to pedestal structure  602  in various ways including protrusions  130  described herein. In some embodiments as depicted in charging device  600 , a surface of pedestal structure  602  can be sheared, thereby forming an angle with a surface of base structure  604 . In some embodiments, this angle can be less than forty five degrees, thereby preventing a mobile device from sliding off while placed on the sheared surface of pedestal  602 . Although not shown in  FIG. 6A , charging device  600  can include a support member near the base of pedestal structure configured to prevent such sliding of a mobile device. In some embodiments, when a mobile device is placed on charging assembly  100  of charging device  600 , magnet  350  (shown in  FIG. 3 ) can interact with a corresponding magnet within the mobile device, thereby helping align transmitter coil  315  and the inductive receiver coil in the mobile device for efficient power transfer. Magnet  350  in charging assembly  100  can also interact with the magnet in the mobile device to prevent the mobile device from sliding off the charging device. 
     Charging assembly  100  can be mounted in pedestal  602  such that charging surface  115  faces outward on the sheared surface of pedestal  602  as shown in  FIG. 6A . In some embodiments, a mobile device such as a smart watch can be placed on charging surface  115  for charging. Power, such as USB power, can be supplied to charging device  600  through a power source  606  in base structure  604 . Power source  606  can be connected to an AC outlet, USB charging port, a power adapter, or other appropriate source of power. In some embodiments, charging device  600  can function as a night-stand for a wearable mobile device or other mobile device. From a user&#39;s perspective, all that may be visible of charging assembly  100  can be charging surface  115 . The rest of the components of charging assembly  100  can be disposed in housing  140  inside pedestal  602  and hence hidden from view. Charging device  600  can provide additional functionality apart from charging mobile devices in some embodiments. 
       FIG. 6B  is a simplified illustration of another example charging device  610  incorporating charging assembly  100 . As shown in  FIG. 6B , charging device  610  includes a base structure  612 . Base structure  612  comprises a recess in which charging assembly  100  is disposed with charging surface  115  visible to a user. Charging device  610  can be connected to a source of power supply through power source  614  in base structure  612 . As shown in  FIG. 6B , charging device  610  can include a planar arrangement where a shared outer surface includes charging surface  115  of charging assembly  100  and an outer surface of base structure  612 . In some embodiments, a portion of charging surface  115  (e.g., the peripheral outer region) can be concealed by the outer surface of base structure  612 . Charging device  610  can provide additional functionality apart from charging mobile devices in some embodiments. 
       FIG. 6C  is simplified illustration of another example charging device  620  incorporating charging assembly  100 . Charging device  620  can be a portable battery and can include a power storage battery not shown in  FIG. 6C . As shown in  FIG. 6C , charging device  620  includes a base structure  622  comprising a storage battery and a power source  624 . Power source  624  can be connected to a power supply such as a USB power supply, thereby charging the battery in base structure  622 . In some embodiments, the battery in base structure  622  can be charged by placing charging device  620  in a battery charging unit. Although depicted as a cylinder in  FIG. 6C , base structure  622  can be in any appropriate shape and geometry. Charging assembly  100  can be mounted on top of charging device  620  such that charging surface  115  is exposed (e.g., at the top of the cylinder). 
     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 the specific embodiments described herein are presented for purposes of illustration and description. They are not target to be exhaustive or to limit the 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 teaching

Metadata:
Filing Date: 20150930
Publication Date: 20190924
Grant Date: 20190924
Priority Date: 20150930
Inventors: GRAHAM, Christopher S.
THOMPSON, PAUL J.
Assignee: APPLE INC
CPC Classifications: [{"code": "H02J50/70", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F38/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "H02J7/0044", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0044", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01F38/14", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01F2038/143", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01F38/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "H02J7/025", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01F38/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/365", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0042", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/362", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/0037", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/0081", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0044", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0042", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J50/70", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/361", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/361", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F2038/143", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01F27/36", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0042", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01F27/36", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/361", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/79", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/79", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J50/70", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F38/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0044", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K9/0081", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/79", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 56799294