Power supply device

Abstract

To make a magnetic attraction force into an appropriate magnitude in a direction that is opposite to a magnetic substance while securing a holding power in a direction parallel to the magnetic substance when holding a power transmitter and a power receptor using a magnet.SOLUTION: A power supply device can transmit power in a non-contact manner from a power transmission coil to a power reception coil when a power transmitter and a power receptor come into contact with each other. The power transmitter includes a convex-like housing part housing a power reception part and a soft magnetic material. The power transmitter includes: a main body part to which a concave-like contact surface that houses the power transmitter and is in contact with the housing part; a magnet; and a spring. The magnet can be slit in a direction where the spring is compressed by a magnetic suction force with the soft magnet material along a cylinder side surface in a state where the power transmission part and the power receptor face each other in a horizontal direction. In a state where the contact surface is in a surface contact with the housing part, the power transmitter is held in the horizontal direction by the magnetic suction force, and an upper surface of the housing part supports the main body part, so that the power transmitter is held in a vertical direction so as to be not move downward.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a power supply device. [Background technology]

[0002] Patent document 1 discloses an electric field coupling type contactless power supply system that includes a power transmission sheet installed on a wall made of a magnetic material and a power receiver having a magnet, and that positions the power receiver relative to the power transmission sheet by the magnetic attraction force generated between the magnetic material and the magnet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-085790 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration described in Patent Document 1, the power receiver is held by the magnetic attraction force between the magnet and the magnetic body, so the holding force is weak in a direction parallel to the magnetic body. Also, the attraction force is strong when connecting the power receiver in a direction facing the magnetic body, and when the magnet and magnetic body are close to each other, the magnetic attraction force changes sharply.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a power supply device that can ensure a holding force in a direction parallel to the magnetic body when holding a power transmitter and a power receiver using a magnet, while making the magnetic attraction force of an appropriate magnitude in the direction facing the magnetic body. [Means for solving the problem]

[0006] The present invention relates to a power supply device that includes a power transmitter having a power transmission coil electrically connected to an external power source, and a power receiver that is provided in a vehicle capable of external charging and has a power receiving coil that receives power transmitted in a non-contact manner from the power transmission coil, and that is capable of transmitting power in a non-contact manner from the power transmission coil to the power receiving coil when the power transmitter and the power receiver come into contact with each other in a state in which the vehicle is stopped. The power receiver houses a power receiving unit including the power receiving coil and has a convex housing part that protrudes from the vehicle body to the outside of the vehicle, and a soft magnetic material fixed to an inner surface of the housing part. The power transmitter houses a power transmission unit including the power transmission coil and has a main body part provided with a concave contact surface that contacts the housing part, and a cylindrical The cylinder has a magnet provided inside and arranged at a position corresponding to the soft magnetic material, and a spring provided inside the cylinder between the magnet and the bottom surface of the cylinder, wherein when the main body approaches the housing with the power transmitting surface of the power transmitting unit and the power receiving surface of the power receiving unit facing each other horizontally, the magnet can slide inside the cylinder along the side of the cylinder in a direction compressing the spring due to the magnetic attraction force generated between the magnet and the soft magnetic material, and when the contact surface is in face-to-face contact with the housing, the magnetic attraction force holds the power transmitter horizontally, and the top surface of the housing supports the main body, thereby holding the power transmitter vertically so that it does not move downward. Effect of the Invention

[0007] In the present invention, when the power transmitter and the power receiver are connected by the magnetic attraction force between the magnet and the magnetic material, the weight of the power transmitter is received by the top surface of the housing, so that the vertical holding force of the power transmitter can be secured. In addition, in the horizontal direction, the magnet moves horizontally inside the cylinder against the biasing force of the spring, so the distance between the magnet and the soft magnetic material is gradually reduced, and the change in the magnetic attraction force can be made gradual. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating a power supply device according to an embodiment. [Diagram 2]FIG. 2 is a diagram showing a power receiver provided in a vehicle. [Diagram 3] FIG. 3 is a diagram illustrating a schematic diagram of a power transmitter. [Figure 4] FIG. 4 is a cross-sectional view taken along line AA of FIG. [Diagram 5] FIG. 5 is a diagram illustrating a power receiver. [Figure 6] FIG. 6 is a cross-sectional view taken along line BB in FIG. [Figure 7] FIG. 7 is a cross-sectional view showing a state in which the power transmitter is connected to the power receiver. [Figure 8] Figure 8(a) is a schematic diagram showing the state before the power transmitter is connected to the power receiver, Figure 8(b) is a schematic diagram showing the state in which the power transmitter and the power receiver are in contact, and Figure 8(c) is a schematic diagram showing the state in which a magnet attracted by magnetic attraction force compresses the spring. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a power supply device according to an embodiment of the present invention will be specifically described, however, the present invention is not limited to the embodiment described below.

[0010] As shown in FIG. 1 and FIG. 2, the power supply device 1 includes a power transmitter 2 and a power receiver 3. The power supply device 1 is a device capable of transmitting power contactlessly from the power transmitting coil of the power transmitter 2 to the power receiving coil of the power receiver 3 when the power transmitter 2 and the power receiver 3 come into contact with each other while the vehicle 100 is stopped. The power transmitter 2 is a device having a power transmitting coil electrically connected to an external power source. The power transmitting coil of the power transmitter 2 is connected to the external power source via a charging cable. The power transmitter 2 is installed, for example, in a parking lot. The power receiver 3 is installed in the vehicle 100 capable of external charging, and is a device having a power receiving coil that receives power transmitted contactlessly from the power transmitting coil of the power transmitter 2. The power receiver 3 is formed in a substantially rectangular convex structure that protrudes horizontally from the body of the vehicle 100 toward the outside of the vehicle. The power receiving coil of the power receiver 3 is electrically connected to the battery of the vehicle 100. The vehicle 100 can be externally charged by wireless power supply using a power transmitter 2 and a power receiver 3. Note that only a portion of the body of the vehicle 100 is shown in Figs. 1 and 2.

[0011] As shown in FIGS. 3 and 4, the power transmitter 2 includes a power transmitting section 11, a main body section 12, a magnet 13, and a spring 14.

[0012] The power transmission unit 11 is a power transmission device including a power transmission coil. The main body 12 is a structure to which the power transmission unit 11 is attached, and is a structure in which a concave contact surface 20 that contacts the power receiver 3 is formed. The concave contact surface 20 includes a connection surface 21 and an abutment surface 22. The connection surface 21 is a rectangular flat surface that forms the bottom surface of the recess, and is an opposing surface that faces the power receiver 3 in the horizontal direction when connected to the power receiver 3. The connection surface 21 is formed to include a power transmission surface 211 and an adsorption surface 212. The connection surface 21 is formed in an overall shape of a square, and a part of its area functions as the power transmission surface 211 and the adsorption surface 212. The power transmission surface 211 is a surface that extends to a position corresponding to the power transmission unit 11. The power transmission unit 11 is housed in the main body 12 with a part of it exposed to the contact surface 20 side. In addition, a magnet 13 is housed in the main body 12. The magnet 13 is provided inside a cylinder 15 formed in the main body 12. The cylinder 15 has a cylindrical side surface and a circular bottom surface. The power transmitting unit 11 is disposed at a position corresponding to the power receiving unit 31 of the power receiver 3, and the magnet 13 is disposed at a position corresponding to the soft magnetic material 33 of the power receiver 3. The power transmitting surface 211 is a surface disposed between the power transmitting coil and the power receiving coil. The attraction surface 212 is a surface that extends to a position corresponding to the magnet 13. The attraction surface 212 is a surface disposed between the magnet 13 and the soft magnetic material 33 of the power receiver 3. Four cylinders 15 are formed in the main body 12 at positions surrounding the power transmitting unit 11.

[0013] A magnet 13 and a spring 14 are housed inside each cylinder 15. The power transmitter 2 includes four magnets 13 and four springs 14. The magnets 13 can slide inside the cylinder 15 along the side of the cylinder. For example, the magnets 13 are made of laminated magnets. The laminated magnets 13 function as cylindrical magnets. The magnets 13 are coated with an electrical insulating material. The springs 14 are provided inside the cylinder 15 between the magnets 13 and the bottom surface of the cylinder. For example, the springs 14 are made of conical springs. In the overall structure of the power transmitter 2, the springs 14 are disposed between the magnets 13 and the contact surface 20. The magnets 13 can slide inside the cylinder 15 in a direction perpendicular to the connection surface 21.

[0014] As shown in FIG. 5 and FIG. 6, the power receiver 3 includes a power receiving section 31, a housing section 32, and a soft magnetic material 33.

[0015] The power receiving unit 31 is a power receiving device including a power receiving coil. The housing unit 32 is a structure that houses the power receiving unit 31 and is a structure that has a convex contact surface 40 on which the power transmitter 2 is attached. The housing unit 32 has a structure in which a part of the housing unit 32 protrudes horizontally from the vehicle body to the outside of the vehicle, and is integrated with the body of the vehicle 100 so that the convex contact surface 40 is formed on the surface of the vehicle body. The contact surface 40 is a surface that forms the surface of the vehicle body of the vehicle 100 and is a convex surface exposed to the outside of the vehicle 100. The soft magnetic material 33 is a magnetic material formed in a flat plate shape and is fixed to the inner surface 321 of the housing unit 32. The power receiving unit 31 is disposed at a position corresponding to the central position inside the housing unit 32. The soft magnetic material 33 is disposed around the power receiving unit 31 inside the housing unit 32. The power receiving unit 31 is disposed at a position corresponding to the power transmitting unit 11 of the power transmitter 2, and the soft magnetic material 33 is disposed at a position corresponding to the magnet 13 of the power transmitter 2.

[0016] The convex contact surface 40 includes a vertical surface 41 and an upper surface 42. The vertical surface 41 is a plane parallel to the vertical direction and is a rectangular plane facing the horizontal direction as the surface of the vehicle body. The vertical surface 41 is formed to include a power receiving surface 411 and an attraction surface 412. The entire vertical surface 41 is formed in a square shape, and a part of the square functions as the power receiving surface 411 and the attraction surface 412. The power receiving surface 411 is a surface that extends to a position corresponding to the power receiving unit 31. The attraction surface 412 is a surface that extends to a position corresponding to the soft magnetic material 33. The upper surface 42 is a plane parallel to the horizontal direction and is a rectangular plane facing upward in the vertical direction. The upper surface 42 functions as a surface for positioning the power transmitter 2 and also functions as a surface for supporting the power transmitter 2 so that it does not move downward in the vertical direction by receiving the weight of the power transmitter 2. That is, the upper surface 42 exhibits a function of maintaining the attitude of the power transmitter 2, and also exhibits a function of holding the power transmitter 2 at a desired position in the vertical direction.

[0017] When the vehicle 100 performs external charging, the concave contact surface 20 of the power transmitter 2 comes into surface contact with the convex contact surface 40 of the power receiver 3, thereby connecting the power transmitter 2 and the power receiver 3, as shown in Fig. 7. In the power feeding device 1, the contact surfaces 20, 40 consisting of concave and convex surfaces come into surface contact, thereby connecting the power transmitter 2 and the power receiver 3. The power transmitter 2 is connected to the power receiver 3 and coupled in the horizontal direction of the vehicle 100. When the power transmitting surface 211 of the power transmitter 2 and the power receiving surface 411 of the power receiver 3 face each other in the horizontal direction, the areas corresponding to the four magnets 13 face each other.

[0018] In addition, in a state where the power transmitter 2 and the power receiver 3 are close to each other, as shown in FIG. 8(a), before the contact surface 20 of the power transmitter 2 comes into contact with the contact surface 40 of the power receiver 3, a magnetic attraction force is generated by the magnet 13 and the soft magnetic material 33 as the power transmitter 2 approaches the power receiver 3 in the horizontal direction. Then, as shown in FIG. 8(b) and FIG. 8(c), after the contact surface 20 of the power transmitter 2 comes into contact with the contact surface 40 of the power receiver 3, the power transmitter 2 is connected to the power receiver 3 by a horizontal holding force (adhesive force) due to the magnetic attraction force. In the power supply device 1, in the process of transitioning from the state shown in FIG. 8(a) to the state shown in FIG. 8(b), in order to suppress a sharp change in the magnetic attraction force caused by a shortening of the distance between the magnet 13 and the soft magnetic material 33, the magnet 13 is configured to move horizontally in the cylinder 15 while receiving the biasing force of the spring 14.

[0019] Specifically, as shown in FIG. 8(a), when the horizontal distance between the power transmitter 2 and the power receiver 3 is long, the magnet 13 is in a state where it does not compress the spring 14. As shown in FIG. 8(b), when the connection surface 21 of the power transmitter 2 and the vertical surface 41 of the power receiver 3 come into contact while facing each other horizontally, the magnet 13 slides along the side surface of the cylinder in a direction compressing the spring 14 due to the magnetic attraction force generated by the magnet 13 and the soft magnetic material 33. In this case, the magnet 13 starts to move in a direction compressing the spring 14. The magnet 13 moves against the biasing force of the spring 14 and moves horizontally inside the cylinder 15 to a position close to the soft magnetic material 33. Thereafter, as shown in FIG. 8(c), the magnet 13 stops at a predetermined position with the spring 14 compressed. 8(c), the distance between the magnet 13 and the soft magnetic material 33 changes while the relative positional relationship between the main body 12 of the power transmitter 2 and the housing 32 of the power receiver 3 remains unchanged. Regarding this change in distance, the magnet 13 moves against the biasing force of the spring 14, so the moving speed slows down, that is, the change in the distance between the magnet 13 and the soft magnetic material 33 becomes gradual. When the state shown in FIG. 8(c) is reached, the power transmitter 2 is held by the power receiver 3 by the magnetic attraction force generated in this state, and power is supplied to the vehicle 100.

[0020] As described above, according to the embodiment, a vertical holding force can be secured by the abutment surface 22 of the power transmitter 2 abutting against the upper surface 42 of the power receiver 3. In addition, since the magnet 13 approaches the soft magnetic material 33 against the biasing force of the spring 14, the distance between the magnet 13 and the soft magnetic material 33 can be gradually reduced, and it is possible to prevent abrupt changes in the magnetic attraction force between the magnet 13 and the soft magnetic material 33.

[0021] It should be noted that power transmission surface 211 of power transmission unit 11 does not necessarily have to be provided on the same plane as connection surface 21. In other words, power transmission unit 11 may be housed in main body unit 12 at a position where it is not exposed to connection surface 21, and the entire connection surface 12 may be formed by main body unit 12.

[0022] A contact switch may also be provided on the bottom surface of the cylinder 15. In this case, when the magnet 13 moves in a direction that compresses the spring 14, the magnet 13 comes into contact with the contact switch, and the contact switch switches from an ON state to an OFF state. Furthermore, a control device may be provided that controls wireless power transmission by a signal from the contact switch.

[0023] A sensor for detecting the magnetic flux density may be provided on the bottom surface of the cylinder 15. In this case, when the magnet 13 moves in a direction that contracts the spring 14, the magnetic flux density penetrating the sensor decreases. Furthermore, a control device for controlling the wireless power transmission according to the value of the magnetic flux density may be provided. [Explanation of symbols]

[0024] 1 Power supply device 2. Power Transmitter 3 Power receiver 11 Power transmission section 12 Main body 13. Magnet 14 Spring 15 cylinders 20 Contact surface 21 Connection Surface 22 Contact surface 31 Power receiving section 32 Housing 33 Soft magnetic material 40 Contact surface 41 Vertical Plane 42 Top surface 211 Power Transmission Surface 212 Adsorption surface 321 Inside 411 Receiving surface 412 Adsorption surface

Claims

[Claim 1] a power transmitter having a power transmitting coil electrically connected to an external power source; a power receiver provided in a vehicle capable of external charging, the power receiver having a power receiving coil for receiving power transmitted from the power transmitting coil in a non-contact manner; When the power transmitter and the power receiver are in contact with each other while the vehicle is stopped, the power supply device is capable of transmitting power from the power transmission coil to the power receiving coil in a non-contact manner, The power receiver includes: a convex housing portion that houses a power receiving unit including the power receiving coil and protrudes from a vehicle body toward an outer side of the vehicle; A soft magnetic material fixed to the inner surface of the housing portion, The power transmitter comprises: a main body portion that houses a power transmission unit including the power transmission coil and has a concave contact surface that contacts the housing portion; a magnet provided inside a cylinder formed in the main body and disposed at a position corresponding to the soft magnetic material; a spring provided inside the cylinder between the magnet and a bottom surface of the cylinder; when the main body approaches the housing in a state where a power transmitting surface of the power transmitting unit and a power receiving surface of the power receiving unit face each other horizontally, the magnet is capable of sliding within the cylinder along a side surface of the cylinder in a direction compressing the spring by a magnetic attraction force generated between the magnet and the soft magnetic material, When the contact surface is in surface contact with the housing, the power transmitter is held in a horizontal direction by the magnetic attraction force, and the upper surface of the housing supports the main body, thereby holding the power transmitter in a vertical direction so as not to move downward. A power supply device characterized by:

Images