Uniform wireless charging device

Abstract

In a wireless charging device that includes a resonator having coil windings, a magnetic field can be generated by the resonator. The wireless charging device can include a feed point connected to an inner winding of the coil windings of the resonator. The resonator can inductively couple with a power receiving unit such that the an outer winding of the coil windings limit Eddy current generation in one or more conductive surfaces positioned adjacent to the power receiving unit. The feed point can be selectively connected to the inner winding of the coil in a first mode of operation and the outer winding of the coil in a second mode of operation. The inner winding can have a larger current than the outer winding.

1 - 22 . (canceled) 
     
     
         23 . A wireless charging device, comprising:
 a resonator having coil windings that include an inner winding having an inner coupling and an outer winding having an outer coupling,   wherein the wireless charging device is configured to be selectively operable in:
 a first mode of operation in which the inner coupling is connectable to a power source to power to the resonator; and 
 a second mode of operation in which the outer coupling is connectable to the power source to power the resonator. 
   
     
     
         24 . The wireless charging device of  claim 23 , wherein:
 in the first mode of operation, the outer coupling is electrically closed; and   in the second mode of operation, the inner coupling is electrically closed.   
     
     
         25 . The wireless charging device of  claim 24 , wherein the resonator further comprises an inline capacitor, the outer coupling being electrically closed via the inline capacitor in the first mode of operation and the inner coupling being electrically closed via the inline capacitor in the second mode of operation. 
     
     
         26 . The wireless charging device of  claim 23 , further comprising a controller that is configured to control the wireless charging device to selectively operate in the first and second modes of operation. 
     
     
         27 . The wireless charging device of  claim 23 , wherein the wireless charging device is configured to receive a control signal that controls the wireless charging device to selectively operate in the first and second modes of operation. 
     
     
         28 . The wireless charging device of  claim 23 , further comprising one or more tuning capacitors connected in series between the power source and the coil windings. 
     
     
         29 . The wireless charging device of  claim 23 , wherein the inner winding is an innermost winding of the coil windings and the outer winding is an outermost winding of the coil windings. 
     
     
         30 . The wireless charging device of  claim 23 , wherein the outer winding of the coil windings has a higher impedance than the inner winding. 
     
     
         31 . The wireless charging device of  claim 23 , wherein the coil windings are substantially concentrically arranged. 
     
     
         32 . The wireless charging device of  claim 23 , wherein the resonator is configured to generate a larger current in the inner winding of the coil windings than the outer winding of the coil. 
     
     
         33 . The wireless charging device of  claim 32 , wherein the resonator is configured to generate the larger current in the inner winding of the coil windings than the outer winding of the coil in the presence of one or more conductive surfaces positioned adjacent to the wireless charging device. 
     
     
         34 . The wireless charging device of  claim 23 , wherein the outer winding is configured to limit Eddy current generation in one or more conductive surfaces positioned adjacent to the wireless charging device. 
     
     
         35 . A wireless charging device, comprising:
 a resonator including coil windings that include an inner winding having an inner coupling and an outer winding having an outer coupling, the resonator configured to generate a magnetic field; and   a selectively configured feed connectable to: (a) the inner coupling and (b) the outer coupling, the feed being configured to connect to a power source to power the resonator, wherein:
 in a first mode of operation, the inner coupling are configured to connect to the feed to connect the inner coupling to the power source; and 
 in a second mode of operation, the outer coupling are configured to connect to the feed to the power source. 
   
     
     
         36 . The wireless charging device of  claim 35 , wherein:
 in the first mode of operation, the outer coupling is electrically closed; and   in the second mode of operation, the inner coupling is electrically closed.   
     
     
         37 . The wireless charging device of  claim 36 , wherein the resonator further comprises an inline capacitor, the outer coupling being electrically closed via the inline capacitor in the first mode of operation and the inner coupling being electrically closed via the inline capacitor in the second mode of operation. 
     
     
         38 . The wireless charging device of  claim 35 , wherein, in a third mode of operation, the inner coupling and the outer coupling are configured to connect to the power source. 
     
     
         39 . The wireless charging device of  claim 35 , wherein the feed is selectively connected based on one or more characteristics of the wireless charging device or an associated power receiving unit. 
     
     
         40 . The wireless charging device of  claim 39 , wherein the one or more characteristics comprise: the current of the resonator, a voltage induced in the power receiving unit, and/or a mutual impedance between the wireless charging device and the power receiving unit. 
     
     
         41 . The wireless charging device of  claim 35 , wherein the feed is selectively connected based on a control signal received by the wireless charging device. 
     
     
         42 . The wireless charging device of  claim 35 , further comprising one or more tuning capacitors connected in series between the power source and the coil windings.