CHARGING COIL SYSTEM FOR A DROP-IN TARGET DEVICE SUCH AS A TOOTHBRUSH

• US 20140333260A1
• Filed: 12/10/2012
• Published: 11/13/2014
• Est. Priority Date: 12/22/2011
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Sayles, Thomas Jackson
• Granted Patent: US 9,385,561 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H01F 21/02 continuously variable, e.g. variometers
• CPC Class Codes: H01F 21/04 by relative movement of turns or parts of windings
• CPC Class Codes: H01F 21/06 by movement of core or part of core relative to the windings as a whole
• CPC Class Codes: H01F 21/08 by varying the permeability of the core, e.g. by varying magnetic bias
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/50 using additional energy repeaters between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H02J 7/0044 specially adapted for holding portable devices containing batteries H02J7/0045 takes precedence
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters

Abstract

A system and method for charging at least one target device (29) having a secondary coil (27) positionable in a charging receptacle (25) having a primary coil (23) connected to a source of electrical power, wherein the secondary coil of the target device is out of precise alignment with the primary coil when the target device is positioned in the receptacle. A plurality of steering coils (22-22) are arranged around the primary coil. A control circuit (24) changes the magnetic field phase pattern of the steering coils relative to the phase of magnetic field of the primary coil in a selected sequence until the maximum power transfer between the primary coil and the secondary coil is determined. Charging of the target device is continued with the maximum power transfer steering coil phase pattern.

Claims

1. A system for charging one or more target devices with a receptacle charger, comprising:

a receptacle charger for receiving one or more target devices, the receptacle having a primary coil therein connectable to a source of electrical power;

at least one target device, positionable in the receptacle, the target device having a secondary coil such that in operation energy is transferred between the primary coil and secondary coil to charge a battery in the target device;

a plurality of steering coils arranged around the primary coil; and

a control system for controlling the magnetic field phase of the steering coils relative to the magnetic field of the primary coil so as to focus the magnetic field lines of the primary coil to optimize power transfer between the primary coil in the receptacle charger and the secondary coil of the target device.

2. The system of claim 1, wherein the target device is a power toothbrush.

3. The system of claim 1, wherein the receptacle is a cup suitable for containing fluid for drinking by the user.

4. The system of claim 1, wherein the steering coils are substantially equally spaced around the primary coil.

5. The system of claim 1, wherein the number of steering coils is in the range of 2-32.

6. The system of claim 5, wherein the number of steering coils is 8.

7. The system of claim 1, wherein the control system executes a plurality of steps including repeatedly altering the magnetic field phase of the steering coils in response to successive power determination values received from the target device in order to determine the magnetic field phase pattern which produces the greatest power transfer.

8. The system of claim 1, wherein the control system changes the magnetic field phase pattern of the steering coils in accordance with a predetermined sequence.

9. The system of claim 6, wherein the magnetic field phase condition of the steering coils include in-phase, out-of-phase and off.

10. The system of claim 1, wherein the control system includes a sequence of steps arranged to accommodate power values received from a plurality of target devices with separate IDs, and determining the magnetic field phase pattern producing the maximum power transfer between the primary coil and a selected one of the plurality of target devices.

13. The method of claim 10, wherein the phase pattern of the steering coils is changed in accordance with a preselected sequence until the maximum power transfer is determined.

11. A method for controlling the charging of at least one target device positioned in a receptacle, the target device having a secondary coil and the charging receptacle having a primary coil, wherein a plurality of steering coils are arranged around the primary coil, the method comprising the steps of:

establishing an initial phase condition pattern of the magnetic fields of the steering coils relative to the phase of the magnetic field of the primary coil;

activating the target device;

determining the power transfer between the primary coil and the secondary coil in the target device when the steering coils are in their initial phase condition pattern;

altering the magnetic field phase condition pattern of the steering coils repeatedly until a coil phase pattern is determined which produces a maximum power transfer between the primary coil and the secondary coil; and

charging the secondary coil with the maximum power transfer phase pattern of the steering coils.

12. The method of claim 11, wherein the phase condition of the individual steering coils include in-phase with the primary coil, out-of-phase with the primary coil and off.

14. The method of claim 11, wherein two target devices are charged simultaneously and wherein charging of the two target devices continues with a phase pattern which produces the maximum power transfer between the primary coil and a selected one of the two target devices.