Cavity resonant power transmission device and wireless power transmission system

Patent metadata

Field	Value
Publication number	US-2025246939-A1
Application number	US-202519184184-A
Country	US
Kind code	A1
Filing date	Apr 21, 2025
Priority date	Dec 15, 2023
Publication date	Jul 31, 2025
Grant date	—

Abstract

A cavity resonant power transmission device includes a structure, a power transmitter, and a partition, in which the structure is entirely surrounded by an electromagnetic wave shielding member having conductivity. The power transmitter wirelessly supplies power to a product via a power receiver in an inner space of the structure, and the partition separates the power receiver from the power transmitter. The structure has a bottom portion, a top portion facing the bottom portion, and a side portion connecting outer edges of the bottom portion and the top portion. The power transmitter is in contact with an inner surface of the bottom portion.

First claim

What is claimed is:

1 . A cavity resonant power transmission device comprising:
a structure; a power transmitter; and a partition, wherein the structure is entirely surrounded by an electromagnetic wave shielding member having conductivity, the power transmitter is configured to wirelessly supply power to a product via a power receiver in an inner space of the structure, and the partition separates the power receiver from the power transmitter, the structure has a bottom portion, a top portion facing the bottom portion, and a side portion connecting outer edges of the bottom portion and the top portion, and the power transmitter is in contact with an inner surface of the bottom portion.

2 . The cavity resonant power transmission device according to claim 1 , wherein
the partition is separated from the power transmitter.

3 . The cavity resonant power transmission device according to claim 1 , wherein
a separation distance between the partition and the power transmitter is equal to or greater than ⅓ of a wavelength of a resonant frequency used for wireless power supply.

4 . The cavity resonant power transmission device according to claim 1 , further comprising:
a guide that is configured to restrict a position and direction of the power receiver in a region of the inner space that includes the power receiver.

5 . The cavity resonant power transmission device according to claim 1 , wherein
power is transmitted while switching between odd and even numbers of at least one of indexes m and n of a resonant frequency in the inner space.

6 . The cavity resonant power transmission device according to claim 1 , wherein
when a resonant frequency is in an (m, n, p) mode, power is transmitted while performing switching such that any one of m, n, and p becomes 0.

7 . The cavity resonant power transmission device according to claim 5 , wherein
the resonant frequency is switched at an interval of 0.3 seconds or more.

8 . The cavity resonant power transmission device according to claim 1 , wherein
the power transmitter is only in contact with the inner surface of the bottom portion of the structure.

9 . The cavity resonant power transmission device according to claim 1 , wherein
the structure has a longitudinal direction from the bottom portion to the top portion.

10 . The cavity resonant power transmission device according to claim 9 , wherein
the partition is closer to the bottom portion than to the top portion.

11 . The cavity resonant power transmission device according to claim 9 , further comprising:
a shelf for the power receiver between the partition and the top portion.

12 . The cavity resonant power transmission device according to claim 1 , wherein
a resonant frequency in the inner space is a TE110 mode.

13 . The cavity resonant power transmission device according to claim 1 , wherein
the side portion of the structure has a first side portion and a second side portion facing the first side portion, and the power transmitter is in contact with the inner surface of the bottom portion and an inner surface of the first side portion.

14 . The cavity resonant power transmission device according to claim 13 , wherein
the structure has a longitudinal direction from the first side portion to the second side portion.

15 . The cavity resonant power transmission device according to claim 13 , wherein
the partition is closer to the first side portion than to the second side portion.

16 . The cavity resonant power transmission device according to claim 13 , wherein
the power transmitter is in indirect contact with the inner surface of the bottom portion and in direct contact with the inner surface of the first side portion.

17 . A wireless power transmission system comprising:
the cavity resonant power transmission device according to claim 1 ; and at least one power receiver in the inner space of the structure of the cavity resonant power transmission device, wherein the power transmitter is configured to wirelessly supply power to a product via the power receiver.

18 . The wireless power transmission system according to claim 17 , wherein
the at least one power receiver includes a plurality of power receivers.

19 . The wireless power transmission system according to claim 17 , wherein
the power receiver is separable from the product, the power receiver is connected to a charging terminal of the product, and power is wirelessly supplied in a state where the product is in the inner space of the structure.

20 . The wireless power transmission system according to claim 17 , wherein
the power receiver is in an unpacked state, the power transmitter is configured to wirelessly supply power to the product via the power receiver in the unpacked state.

21 . The wireless power transmission system according to claim 17 , wherein
the power receiver and the product are in a packed state, and the power transmitter is configured to wirelessly supply power to the product via the power receiver in the packed state.

22 . The wireless power transmission system according to claim 21 , wherein
the power receiver and the product are stacked on the partition in the packed state.

Assignees

• Murata Manufacturing Co

Inventors

• Saeki Hiromasa

Classifications

• H02J50/005

  Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices · CPC title

• H02J50/70

  involving the reduction of electric, magnetic or electromagnetic leakage fields · CPC title

• H02J50/12 Primary

  of the resonant type · CPC title

• H02J50/40

  using two or more transmitting or receiving devices (H02J50/50 takes precedence) · CPC title

• H02J50/20

  using microwaves or radio frequency waves · CPC title