Method for charging a mobile terminal with a mobile device with which a motor vehicle is intended to be equipped and associated charging device

1. A method for charging a mobile terminal using a charging device configured to be housed on board a motor vehicle, said charging device comprising at least one first induction charging antenna, having a charging frequency, and a second resonance charging antenna, or having a resonant frequency at least 1000 times higher than the charging frequency, a ferromagnetic body situated below and joined to the inductive primary antenna, the charging method comprising:

equipping the ferromagnetic body and the inductive primary antenna beforehand with movement means able to move the ferromagnetic body and said inductive primary antenna with respect to the resonant primary antenna,

detecting the mobile terminal on a charging surface,

determining a type of charging between the charging device and the mobile terminal so as to trigger charging by the inductive primary antenna or the resonant primary antenna,

moving the ferromagnetic body joined to the inductive primary antenna with respect to the resonant primary antenna, depending on the resonant frequency of said resonant primary antenna when the mobile terminal is charged by the resonant primary antenna, and

moving the ferromagnetic body joined to the inductive primary antenna depending on a charging efficiency of the inductive primary antenna when the mobile terminal is charged by the inductive primary antenna.

2. The charging method as claimed in claim 1 , wherein:

the detection step and the determination step are performed by way of the resonant primary antenna, and

the determination step comprises the resonant primary antenna sending an identifier request message to the mobile terminal,

if a compatible identifier is received in return by the resonant primary antenna from the mobile terminal, the mobile terminal is charged by way of the resonant primary antenna,

otherwise, the mobile terminal is charged by way of the inductive primary antenna.

3. The charging method as claimed in claim 2 , wherein,

when the mobile terminal is charged by the resonant primary antenna, the movement of the ferromagnetic body joined to the inductive primary antenna stops only when the resonant frequency is contained within a window of predetermined values, and

when the mobile terminal is charged by the inductive primary antenna, the movement of the ferromagnetic body joined to the inductive primary antenna stops only when the charging efficiency of the inductive primary antenna is higher than or equal to a predetermined threshold.

4. The method as claimed in claim 1 , wherein the movement of the inductive primary antenna and of the ferromagnetic body takes place in a plane parallel to the charging surface.

5. A charging device for charging a mobile terminal, configured to be housed on board a motor vehicle, said charging device comprising at least one first induction charging antenna, having a charging frequency, and a second resonance charging antenna, having a resonant frequency at least 1000 times higher than the charging frequency, a ferromagnetic body situated below and joined to the inductive primary antenna, the charging device comprising:

movement means for moving the ferromagnetic body joined to the inductive primary antenna, able to move the ferromagnetic body and the inductive primary antenna, and

a microcontroller configured to:

detect the presence of the mobile terminal on a charging surface,

determine a type of charging,

measure a resonant frequency of the resonant primary antenna,

measure a charging efficiency of the inductive primary antenna,

control the movement means depending on the resonant frequency,

control the movement means depending on the charging efficiency,

compare the resonant frequency of the resonant primary antenna and a minimum value and a maximum value of a window of predetermined values, and

compare the charging efficiency of the inductive primary antenna and a predetermined threshold.

6. The charging device as claimed in claim 5 , wherein, with the charging surface comprising a longitudinal axis and a transverse axis that intersect at a center, the resonant primary antenna is situated at ends of the charging surface and the ferromagnetic body and the inductive primary antenna are configured to move along the longitudinal axis from an initial position in which the inductive primary antenna or the ferromagnetic body has a center coincident with a center of the charging surface to a final position in which the inductive primary antenna or the ferromagnetic body is situated close to the resonant primary antenna at the ends of the charging surface.

7. The charging device as claimed in claim 5 , wherein the resonant primary antenna fully or partly surrounds the inductive primary antenna.

8. The charging device as claimed in claim 5 , wherein the movement of the inductive primary antenna and of the ferromagnetic body takes place in a plane parallel to the charging surface and in that the movement means comprise:

an electric motor, and

a drive system comprising at least two pulleys, around which a belt, joined to the ferromagnetic body, is driven in motion.

9. A motor vehicle, comprising a charging device as claimed in claim 5 .

10. The charging method as claimed in claim 1 , wherein,

when the mobile terminal is charged by the resonant primary antenna, the movement of the ferromagnetic body joined to the inductive primary antenna stops only when the resonant frequency is contained within a window of predetermined values, and

when the mobile terminal is charged by the inductive primary antenna, the movement of the ferromagnetic body joined to the inductive primary antenna stops only when the charging efficiency of the inductive primary antenna is higher than or equal to a predetermined threshold.

11. The charging device as claimed in claim 6 , wherein the resonant primary antenna fully or partly surrounds the inductive primary antenna.