Inductively powered apparatus
An inductive power supply system for providing power to one or more inductively powered devices. The system includes a mechanism for varying the physical distance or the respective orientation between the primary coil and secondary coil to control the amount of power supplied to the inductively powered device. In another aspect, the present invention is directed to an inductive power supply system having a primary coil and a receptacle disposed within the magnetic field generated by the primary coil. One or more inductively powered devices are placed randomly within the receptacle to receive power inductively from the primary coil. The power supply circuit includes circuitry for adjusting the power supplied to the primary coil to optimize operation based on the position and cumulative characteristics of the inductively powered device(s) disposed within the receptacle.
1. A secondary for an inductively powered device comprising:
a first coil arranged at a first angular orientation for receiving inductive power;
a second coil arranged at a second angular orientation for receiving inductive power, said first angular orientation being different from said second orientation, wherein said first coil and said second coil are coreless; and
a circuit for electrically connecting said first coil and said second coil in parallel with a common load.
2. The secondary of claim 1 wherein said first angular orientation and said second angular orientation are about ninety degrees apart.
3. The secondary of claim 1 further comprising a third coil arranged at a third angular orientation for receiving inductive power, said third angular orientation being different from said first orientation and said second orientation.
4. The secondary of claim 3 wherein said first angular orientation, said second angular orientation and said third angular orientation are each about ninety degrees apart from one another.
5. The secondary of claim 4 further comprising a capacitor connected in series between said load and each of said first coil, said second coil and said third coil.
6. The secondary of claim 3 wherein said first coil, said second coil and said third coil are electrically connected in a half-bridge arrangement with a diode connected in series between said load and each of said first coil, said second coil and said third coil.
7. The secondary of claim 3 wherein said first coil, said second coil and said third coil are electrically connected in a full bridge arrangement with a pair of diodes connected in series between said load and opposite sides of each of said first coil, said second coil and said third coil.
8. The secondary of claim 3 wherein said first coil, said second coil and said third coil are wrapped about a common bobbin.
9. The secondary of claim 3 wherein said first coil, said second coil and said third coil are wrapped about a common substantially spherical bobbin.
10. The secondary of claim 3 wherein said first coil is wrapped about a first bobbin, said second coil is wrapped about a second bobbin and said third coil is wrapped about a third bobbin.
11. The secondary of claim 10 wherein said first bobbin is fitted within said second bobbin and said second bobbin is fitted within said third bobbin.
12. The secondary of claim 10 wherein said first bobbin has a first diameter, said second bobbin has a second diameter and said third bobbin has a third diameter, said first diameter being smaller than said second diameter, said second diameter being smaller than said third diameter; and
wherein said first coil includes a greater number of turns than said second coil and said second coil includes a greater number of turns than said third coil.