Power transmission device and antenna

• US 10,361,592 B2
• Filed: 08/03/2015
• Issued: 07/23/2019
• Est. Priority Date: 08/03/2015
• Status: Active Grant

• Current Assignee: Mitsubshi Electric Engineering Company Limited (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubshi Electric Engineering Company Limited (Mitsubishi Electric Corporation)
• Inventors: Akuzawa, Yoshiyuki, Ito, Yuki
• Primary Examiner(s): Cavallari, Daniel J
• Application Number:
  US15/743,886
• Publication Number:
  US 20180205264A1
• Time in Patent Office: 1,450 Days
• CPC Class Codes: B60L 9/00 Electric propulsion with power supply external to the vehicle electric propulsion for monorail vehicles, suspension vehicles or rack railways B60L13/00; in combination with batteries or fuel cells within the vehicle B60L50/53
• CPC Class Codes: H01Q 1/248 provided with an AC/DC converting device, e.g. rectennas
• CPC Class Codes: H01Q 7/06 with core of ferromagnetic material H01Q7/02 takes precedence
• CPC Class Codes: H02J 50/12 of the resonant type

Abstract

A transmission/reception unit including a transmitting antenna and a receiving antenna for carrying out a wireless power transmission in cooperation with the transmitting antenna. Each of the transmitting antenna and the receiving antenna includes a coil which has a shape in which a portion through which a current flows in a direction extends along another portion through which a current flows in an opposite direction.

Claims

1. A power transmission device comprising one or more transmission/reception units each of which includes a transmitting antenna and a receiving antenna for carrying out a wireless power transmission in cooperation with the transmitting antenna, wherein

the transmitting and receiving antennas include a first coil and a second coil, respectively;

each of the first and second coils has a first arc-shaped portion through which a current flows in a direction, and has a second arc-shaped portion through which a current flows in an opposite direction; and

the first arc-shaped portion extends along the second arc-shaped portion.

2. The power transmission device according to claim 1, wherein the transmission/reception unit is arranged apart, at a distance of one-tenth or more of an inner diameter of a minimum-sized antenna of the transmitting and receiving antennas, from a metallic member.

3. The power transmission device according to claim 1, further comprising a shielding member arranged between the transmission/reception unit and a metallic member.

4. The power transmission device according to claim 3, wherein the shielding member is a magnetic sheet or a metallic loop.

5. The power transmission device according to claim 3, wherein the shielding member has a magnetic sheet and a conductor containing free electrons and being opposite to the magnetic sheet.

6. The power transmission device according to claim 1, wherein a plurality of the transmission/reception units is disposed.

7. The power transmission device according to claim 1, wherein the transmission/reception unit carries out a wireless power transmission by using magnetic-field resonance, electric-field resonance, or electromagnetic induction.

8. The power transmission device according to claim 6, wherein a difference in magnetic phase is formed between the adjacent transmission/reception units.

9. The power transmission device according to claim 1, wherein each of the transmitting and receiving antennas includes two or more coils.

10. The power transmission device according to claim 1, wherein the receiving antenna is disposed in a moving object, and the transmitting antenna is disposed in a fixed surface which is opposite to the moving object while the moving object is traveling or when the moving object is standing.

11. The power transmission device according to claim 1, wherein the first arc-shaped portion is arranged parallel to the second arc-shaped section, and the first and second portions are disposed in a same plane.

12. The power transmission device according to claim 1, wherein the first arc-shaped portion is arranged about an axis at a first radial distance from the axis, and the second arc-shaped portion is arranged about the axis at a second radial distance from the axis less than the first radial distance.

13. The power transmission device according to claim 1, wherein:

each of the first and second coils has a C-shape;

the first arc-shaped portion is arranged along an outer curved portion of the C-shape; and

the second arc-shaped portion is arranged along an inner curved portion of the C-shape.

14. The power transmission device according to claim 1, wherein:

the first arc-shaped portion has two ends between which a gap exists, and has a lead portion for connection to a feed terminal;

the second arc-shaped portion has both ends connected to the two ends of the first arc-shaped portion, respectively; and

the first arc-shaped portion has a first radius of curvature greater than a second radius of curvature of the second arc-shaped portion.

15. The power transmission device according to claim 1, wherein the first and second coils are arranged on a same plane, and the second coil is disposed on an inner side of the first coil.