JP7461267B2 - Wireless power supply floor structure - Google Patents

Description

The present invention relates to a wireless power supply floor structure that wirelessly supplies power to an electrically driven vehicle.

Conventionally, power has been supplied wirelessly from the floor to electric cars, electric carts, AGVs (Automated Guided Vehicles), etc. One method of wireless power supply is the magnetic resonance method, in which a high-frequency alternating current is passed through a power transmission electrode installed on the floor to generate a magnetic field, which then generates an induced current in a power receiving electrode to drive the vehicle's motor. For example, the following structure has been proposed as a wireless power supply floor structure (see Patent Documents 1 and 2).

Patent Document 1 describes a base body such as a floor slab or roadbed, a metal member laminated on the base body, a base side member laminated on the metal member, and a first base body side member arranged at predetermined intervals on the base body side member. A wireless power supply floor structure is shown that includes a conductor, a second conductor, and a surface member laminated on a base member with the first conductor and the second conductor interposed therebetween. The base member and the surface member are made of an asphalt material or a cement material mixed with ceramics or the like. The first conductor and the second conductor are sheet members made of metal such as iron, aluminum, and stainless steel.
Patent Document 2 describes a base, a ground plate laminated on the base, a base layer material having insulating properties laminated on the ground plate, and a first power supply electrode and a second power supply electrode provided on the base layer material. A wireless power supply floor structure is shown that includes a power supply electrode and a surface layer material made of a material with low dielectric loss that is laminated on a base material with the power supply electrode sandwiched therebetween. The base layer material and the surface layer material are made of asphalt material or cement material mixed with ceramics.
Patent Document 3 discloses that a copper foil or a plain weave mesh is adhered to the surface of the floor base, a resin mortar of epoxy resin is applied thereon to form a resin mortar layer, and a resin mortar layer of hard urethane resin, epoxy resin, etc. is applied on top of it. A painted floor structure for a wireless powered floor is shown in which a finished coat is applied and a finished coat layer is provided.

In the wireless power supply floor structure of Patent Document 1, the base side member and the surface member are made of asphalt material or cement-based material, and the thickness of the floor is 10 mm or more, so that there are cases where a step occurs on the floor surface when a vehicle is running. In addition, since the asphalt material or cement-based material constituting the base side member and the surface member takes time to harden, there is a problem that it is difficult to carry out renovation work in an operating production facility.
The wireless power supply floor structure of Patent Document 2 also has the same problem because the base layer and surface layer are made of asphalt or cement-based materials.
The same problem occurred with the coated floor structure for a wireless power supply floor in Patent Document 3, because resin mortar is applied onto the surface of the subfloor.

JP2017-163798A Japanese Patent Application Publication No. 2018-065407 Japanese Patent Application Publication No. 2019-203301

An object of the present invention is to provide a wireless power supply floor structure that can reduce the thickness of the floor and can be constructed in a short time.

The wireless power supply floor structure (e.g., the wireless power supply floor structure 1 described below) of the present disclosure is a wireless power supply floor structure that wirelessly supplies power to an electrically powered vehicle (e.g., the vehicle 2 described below), and includes a metal layer (e.g., the ground 10 described below) provided on a base (e.g., the existing floor 3 described below), an adhesive layer (e.g., the adhesive layer 11 described below) that adheres the metal layer to the base, an insulating layer (e.g., the insulating layer 12 described below) provided on the adhesive layer, and a protective layer (e.g., the protective layer 15 described below) including a power transmission electrode (e.g., the power transmission electrode 14 described below) adhered onto the insulating layer, and is characterized in that the power transmission electrode is supplied with power from a high-frequency power source to generate an induced current in the power receiving electrode of the vehicle.
According to this disclosure, the wireless power supply floor is constructed using a dry construction method in which each layer is bonded together, making construction relatively easy and allowing the wireless power supply floor to be constructed in a short construction period.

The wireless power supply floor structure of the present disclosure may include an adhesive layer (for example, adhesive layer 13 described below) or a second adhesive layer that adheres the insulating layer to the adhesive layer.
Further, in the wireless power supply floor structure of the present disclosure, an insulating layer containing a resin material whose heat loss in a frequency band of 6 MHz or more and 15 MHz or less may be smaller than that in other frequency bands may be formed by a dry method. In this way, the thickness of the wireless power supply floor can be made thinner, and since the insulating layer contains less water and carbon, it is possible to suppress the increase in dielectric loss tangent, making it possible to create a wireless power supply floor with excellent power transmission efficiency. realizable.
In the wireless power supply floor structure of the present disclosure, the insulating layer preferably contains at least one material selected from polyolefin, polyester, polyvinyl chloride, acrylic resin, and natural rubber.

In the wireless power supply floor structure of the present disclosure, the protective layer may contain at least one or more materials selected from the group consisting of polyolefin resin, polyester, polyvinyl chloride, and acrylic resin, and may be a floor finishing layer formed by combining at least one or more materials selected from the group consisting of polyolefin, polyester, polyvinyl chloride, and acrylic resin.
According to this disclosure, it is possible to suppress an increase in the dielectric tangent, and to realize a wireless power supplying bed with superior power transmission efficiency.

The protective layer (finishing layer) can be formed by combining at least one of the following materials: polyolefin, polyester, polyvinyl chloride, and acrylic resin, which have excellent abrasion resistance against friction with tires and high dielectric strength against the high-frequency electric field generated during wireless power supply.
According to this disclosure, the protective layer is formed of a material that has self-extinguishing properties and will not catch fire even if the thickness of the material is reduced due to wear from the tire or if the protective layer is destroyed by discharge due to the application of an electric field exceeding the dielectric strength. Note that self-extinguishing properties refer to the property of self-extinguishing when the heat source is removed in the atmosphere, and are physical properties that allow a fire to continue burning if there is a fire source, but cannot continue burning when the fire source is removed. In addition, it is preferable that the protective layer has properties such as a thin thickness (100 μm or less) and a low dielectric loss tangent (no resistor such as carbon, low loss against high frequency electric fields).

In the wireless power supply floor structure of the present disclosure, the metal layer may be formed of a metal sheet having an opening.
The openings referred to here include gaps between adjacent metal materials and mesh processing applied to a single metal material. Therefore, the metal sheet with openings is not limited to metal with a mesh processing.
According to this disclosure, the metal layer is formed from a metal sheet having openings, so that a thin metal layer having high adhesive strength to the substrate can be easily applied onto the substrate.
Furthermore, by providing openings between the metal members of the metal sheet or within the metal sheet itself, it is possible to prevent air from entering the metal sheet when it is bonded to the base.
In addition, by laying a metal sheet on the base and applying adhesive to it, the metal sheet can be adhered to the base and an adhesive layer for adhering the insulating layer can be formed at the same time, thereby shortening the construction period.

In the wireless power supply floor structure of the present disclosure, the metal layer has an opening sufficient for the adhesive to pass from above to below the metal layer, and has a thickness equal to or greater than the skin depth of the frequency at which wireless power supply is performed. A metal body containing at least one material selected from copper, stainless steel, and aluminum can be used, and the end portions may be etched to eliminate protrusions.
By using a mesh with openings for the ground instead of foil, the mesh size is large enough to be impregnated with adhesive, and the thickness satisfies the skin depth of the high-frequency electric field, making it possible to install the ground in one go. . As a result, the thickness of the flooring material can be reduced and it can be constructed in a short period of time.

In the wireless power supply floor structure of the present disclosure, it is preferable that the protective layer is not destroyed by an electric field with a strength of 16 kV/mm.
According to this disclosure, it is possible to suppress an increase in dielectric loss tangent, and it is possible to realize a wireless power feeding floor with more excellent power transmission efficiency.

In the wireless power supply floor structure of the present disclosure, a coating layer may be provided on the upper surface of the protective layer. The coating layer is provided for the purpose of imparting scratch resistance, slipperiness, chemical resistance, or the like.
In the wireless power supply floor structure disclosed herein, the power transmission electrode can be a metal body such as copper, stainless steel, or aluminum having a thickness equal to or greater than the skin depth of the frequency at which wireless power supply is performed, and is a tape material having the protective layer on top and an adhesive layer on the bottom, and the ends can be etched to eliminate any protrusions.
According to this disclosure, by forming the power transmission electrode from an adhesive tape having a protective layer, even if the electrode is damaged by the vehicle being driven, it can be relatively easily repaired.

According to the present invention, it is possible to provide a wireless power supply floor that can be made thinner and can be constructed in a short time.

FIG. 1 is a perspective view of a wireless power supply floor structure according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a wireless power supply floor structure. 13A to 13C are diagrams showing the test results of a power transmission test of a wireless power supply floor structure. FIG. 1 is a diagram showing the measurement results of the dielectric breakdown strength for test specimens 1 to 3. FIG. 13 is a diagram showing the measurement results of the dielectric breakdown strength for test specimens 4 to 6.

The present invention is a wireless power supply floor structure that wirelessly supplies power to electric vehicles, electric carts, AGVs, etc. In the wireless power supply floor structure, an insulating layer is formed of a resin material, and a protective layer including a ground (metal layer), an insulating layer, and a power transmission electrode is bonded using a dry method.
Hereinafter, one embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of a wireless power supply floor structure 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the wireless power supply floor structure 1.

The wireless power supply floor structure 1 wirelessly supplies power to a vehicle 2 that runs electrically. This wireless power supply floor structure 1 includes a ground 10 as a metal layer provided on an existing floor 3 as a reinforced concrete base, an adhesive layer 11 for bonding the ground 10 to the existing floor 3, and a ground 10 provided on the adhesive layer 11. an adhesive layer 13 that adheres the insulating layer 12 to the adhesive layer 11; and a protective layer for preventing electric shock that includes polyolefin and the like and includes the power transmission electrode 14 and is adhered onto the insulating layer 12 with the adhesive layer 16. 15. Although not shown, the insulating layer 12 may be bonded to the ground 10 with an adhesive layer 11.

The ground 10 is a shield that protects the power transmission electrode 14 from electromagnetic leakage and electromagnetic interference, and is, for example, copper foil or stainless steel plain-woven wire mesh.
The insulating layer 12 is made of a resin material, such as a polyolefin resin, which has less heat loss in a frequency band of 6 MHz or more and 15 MHz or less than in a frequency band of less than 6 MHz and more than 15 MHz, and does not contain water or carbon.
Further, for example, the thickness of the ground 10 is 35 μm, the thickness of the insulating layer 12 is 4 mm, and the thickness of the power transmission electrode 14 is 35 μm. Further, the thickness of the protective layer 15 is 65 μm in the portion where the power transmission electrode 14 is provided, and 100 μm in other portions. Therefore, the overall thickness of the wireless power supply floor structure 1 is approximately 4 mm. Also, for example, when a ground and electrode with a thickness of 35 μm are constructed of copper, the electrode can be reliably covered with the ground by setting the aperture ratio (metal area/total area x 100) to 60% or more. , it becomes possible to prevent electromagnetic leakage and electromagnetic interference.

The power transmitting electrode 14 is supplied with power from the high frequency power source 17, and generates an induced current in a power receiving electrode 20 of the vehicle 2, which will be described later.
The vehicle 2 includes a power receiving electrode 20 and a drive device (not shown) that drives wheels 21 using an induced current generated in the power receiving electrode 20. This vehicle 2 moves on the protective layer 15 of the wireless power supply floor structure 1 in the direction of the arrow in FIG. 1 by rotating the wheels 21 by the drive device.

The wireless power supply floor structure 1 described above is constructed, for example, by the following procedure.
First, prepare a sheet made of copper foil or stainless steel plain-woven wire mesh, place this metal sheet on the existing floor 3, and apply adhesive to impregnate the sheet with the adhesive. is used as a ground 10, and a cured adhesive is used as an adhesive layer 11. Next, a sheet made of polyolefin resin is prepared, an adhesive material is applied on the adhesive layer 11 to form an adhesive layer 13, and a sheet made of polyolefin resin is spread on this adhesive layer 13 to form an insulating layer 12. . Next, a polyolefin resin sheet (tape material) having an adhesive layer 16 on the lower surface and a built-in long metal sheet is prepared, and this sheet is laid on the insulating layer 12. An adhesive layer 16 is adhered onto the insulating layer 12. The metal part of this sheet is used as the power transmission electrode 14, and the polyolefin resin part is used as the protective layer 15.

In order to confirm the durability of the above wireless power supply floor structure, a caster chair test was performed. Specifically, the caster was rotated 3000 times under a load of 100 kg for the wireless power supply floor structure of the present invention (thickness of ground 10: 35 μm, thickness of insulating layer: 4 mm, thickness of power transmission electrode: 35 μm, thickness of protective layer: 100 μm). As a result, it was confirmed that no cracks or deflections occurred in the wireless power supply floor structure of the present invention.
In addition, since there was concern about dielectric breakdown in the protective layer made of polyolefin resin, a dielectric strength test was performed on a 4 mm thick polyolefin resin according to the standard JIS C 2110-1. As a result, a dielectric strength of approximately 100 kV/mm was confirmed.

Additionally, power transmission tests were conducted on the above wireless power supply floor structure. Specifically, regarding the wireless power supply floor structure of the present invention (the thickness of the ground 10 is 35 μm, the thickness of the insulating layer is 4 mm, the thickness of the power transmitting electrode is 35 μm, and the thickness of the protective layer is 100 μm), the connection between the power transmitting electrode and the power receiving electrode is The distance was 10 mm, 500 W of power was input from a high frequency power source, and the output of the power receiving electrode was measured. As a result, as shown in FIG. 3, it was confirmed that the received power was approximately 400 W at a frequency around 6.78 MHz, and the power transmission efficiency was approximately 80%.

In addition, six types of dielectric materials were used as test bodies 1 to 6, six samples were prepared for each test body, and the strength of dielectric breakdown was measured. Test specimen 1 is CS-A-t2000-PVC (polyvinyl chloride). Test specimen 2 is CS-B-t600-Olefin (olefin resin). Test specimen 3 is CS-A-t150-PVC (polyvinyl chloride). Test specimen 4 is CS-D-t100-PET (polyethylene terephthalate). Test specimen 5 is CS-E-t100-PET (polyethylene terephthalate, thickness 0.1 mm). Test specimen 6 is CS-F-t160-acryl (acrylic resin, thickness 0.16 mm). 4 and 5 show the measurement results of dielectric breakdown strength for test specimens 1 to 6.

According to this embodiment, there are the following effects.
(1) The ground (metal layer) 10, insulating layer 12, power transmission electrode 14, and protective layer 15 are made of sheet materials, and the wireless power supply floor structure 1 was constructed using a dry method of gluing these sheet materials, so construction is relatively easy. It is easy and a wireless power supply floor can be constructed in a short construction period.
In addition, in the conventional wireless power supply floor structure, the floor thickness was about 10 mm, but in the wireless power supply floor structure 1 of the present invention, the insulating layer 12 is made of polyolefin resin, so the floor thickness can be reduced to about 4 mm. It can be made thinner, and the level difference between it and the existing floor 3 can be reduced.
In addition, since the insulating layer 12 is made of polyolefin resin, the amount of water and carbon contained in the insulating layer 12 is small, making it possible to suppress an increase in dielectric loss tangent, thereby realizing a wireless power supply floor structure 1 with excellent power transmission efficiency. can.
Moreover, since the power transmission electrode 14 is integrally molded with the protective layer 15 for preventing electric shock in advance, the power transmission electrode 14 can be protected reliably and accurately.
In addition, since the ground (metal layer) 10, insulating layer 12, and protective layer 15 including the power transmission electrode 14 are each made of a hardening material, each layer is manufactured at a factory under high precision control and adhesive is used. The wireless power supply floor structure 1 can be constructed using the dry construction method.
(2) Since the ground 10 is made of copper foil or stainless steel plain-woven wire mesh, the ground 10 can be easily constructed on the existing floor 3.
(3) Since the protective layer 15 is made of polyolefin resin, the amount of water and carbon contained in the protective layer 15 is small, which makes it possible to suppress an increase in dielectric loss tangent, realizing a wireless power supply floor with superior power transmission efficiency. can.

(4) By forming the protective layer 15 from polyolefin resin, polyester, polyvinyl chloride, or acrylic resin, which have excellent dielectric strength, the protective layer (finishing layer) 15 has excellent abrasion resistance against friction with tires and has high dielectric strength against high frequency electric fields generated during wireless power supply. Therefore, it is desirable that the protective layer 15 has high strength and exhibits self-extinguishing properties without ignition, even if a discharge occurs when the vehicle 2 runs on the wireless power supply floor of the present invention.
(5) The ground 10, which is a metal layer, is a mesh-like material having openings large enough for the adhesive to pass from above to below the ground 10, and is a metal body such as copper, stainless steel, or aluminum that has a thickness equal to or greater than the skin depth of the frequency at which wireless power is supplied, and the ends are etched to eliminate protrusions. Therefore, when the adhesive is impregnated into the mesh-like ground 10, a thickness that satisfies the skin depth of the high-frequency electric field can be easily formed. This allows the flooring material to be made thin, and construction can be completed in a short period of time.
(6) The protective layer 15 including the power transmitting electrode 14 is formed of polyolefin by preparing a polyolefin resin sheet with a long metal sheet embedded in it and adhering this sheet onto the insulating layer 12. Therefore, even if the electrode is damaged by the running of the vehicle, it can be repaired relatively easily.

Note that the present invention is not limited to the above-described embodiments, and any modifications, improvements, etc. that can achieve the purpose of the present invention are included in the present invention.
For example, in the above embodiments, the insulating layer is made of polyolefin, but it is not limited to polyolefin, and may be made of at least one of polyester, polyvinyl chloride, acrylic resin, and natural rubber. good.
Further, in the above-described embodiment, the protective layer is formed of polyolefin, but it is not limited to polyolefin, and may be formed by combining at least one of polyester, polyvinyl chloride, and acrylic resin. good.
In the above-described embodiment, the wireless power supply floor structure 1 is provided on the existing floor 3, but the wireless power supply floor structure 1 is not limited thereto, and may be provided on a newly installed floor slab.

1... Wireless power supply floor structure 2... Vehicle 3... Existing floor (foundation)
REFERENCE SIGNS LIST 10: Ground (metal layer) 11: Adhesive layer 12: Insulating layer 13: Adhesive layer 14: Power transmitting electrode 15: Protective layer 16: Adhesive layer 17: High frequency power source 20: Power receiving electrode 21: Wheel

Claims (8)

A wireless power supply floor structure that wirelessly supplies power to an electrically driven vehicle,
A metal layer provided on a substrate;
an adhesive layer that adheres the metal layer to the substrate;
an insulating layer provided on the adhesive layer;
a protective layer adhered onto the insulating layer, the protective layer including a power transmitting electrode;
A wireless power supply floor structure, characterized in that the power transmitting electrode is supplied with power from a high-frequency power source and generates an induced current in the power receiving electrode of the vehicle. The wireless power supply floor structure according to claim 1, further comprising an adhesive layer or a second adhesive layer that adheres the insulating layer to the adhesive layer. The wireless power supply floor structure according to claim 1 or 2, characterized in that the insulating layer contains at least one material selected from the group consisting of polyolefin, polyester, polyvinyl chloride, acrylic resin, and natural rubber. The wireless power supply floor structure according to any one of claims 1 to 3, characterized in that the metal layer is a metal body containing at least one of copper, stainless steel, and aluminum, which has an opening sufficient for the adhesive to pass from above to below the metal layer and has a thickness equal to or greater than the skin depth of the frequency at which wireless power supply is performed. The wireless power supply floor structure according to any one of claims 1 to 4, characterized in that the protective layer is not destroyed by an electric field having a strength of 16 kV/mm. The wireless power supply floor structure according to any one of claims 1 to 5, characterized in that the protective layer contains at least one material selected from the group consisting of polyolefin resin, polyester, polyvinyl chloride, and acrylic resin. The wireless power supply floor structure according to any one of claims 1 to 6, wherein a coating layer is provided on the upper surface of the protective layer. The power transmission electrode is a metal body made of copper, stainless steel, or aluminum and has a thickness equal to or greater than the skin depth of the frequency at which wireless power supply is performed, and is a tape material having the protective layer on the upper side and the adhesive layer on the lower side, The wireless power supply floor structure according to any one of claims 1 to 7, wherein the end portion is etched and has no protrusion.

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