Wireless power transfer system receiver

Abstract

This invention solves the problem of reduced power conversion efficiency due to the configuration angle of the transmitter and receiver in wireless power transfer, and expands the range of application technologies for wireless power transfer by equipping the receiver with a rechargeable battery. [Solution] In a wireless power transfer system 100, the receiver 30 converts the electromagnetic field converted from power by the transmitter 10 into power within the electromagnetic field and has two loop-shaped wiring sections A and B, each configured in the same plane, with the planes to which each loop-shaped wiring section A and B belong being arranged perpendicular to each other, and the magnetic field lines 10a of the electromagnetic field formed by the transmitter 10 always passing inside at least one of the loop-shaped wiring sections A and B. The receiver 30 is equipped with a rechargeable battery 1, and the external size and electrode position shape of the combined loop-shaped wiring sections A and B and the rechargeable battery 1 are the same as those of a commercially available battery. The product housing the receiver 30 is a storage container (not shown) that is stored after operation, and the wireless power transfer function of the transmitter 10 is equipped with this container, eliminating the need for battery replacement.

Description

Technical Field

[0001] The present invention relates to a receiving device of a wireless power transfer system.

Background Art

[0002] A wireless power transfer system has a transmitting unit and a receiving unit. The transmitting unit is connected to a power source and forms an electromagnetic field by power. The receiving unit receives power through the electromagnetic field formed by the transmitting unit, and converts the received power into current for use.

[0003] In the above wireless power transfer system, both the transmitting device disposed in the transmitting unit and the receiving device disposed in the receiving unit have a loop-shaped wiring portion for converting power and an electromagnetic field to transmit and receive power.

[0004] In the conventional wireless power transfer system, the following problems occur during actual use. When converting the electromagnetic field formed in the transmitting unit into current by the receiving unit disposed in the electromagnetic field, depending on the angle formed by the two planes of the plane of the loop-shaped wiring portion of the transmitting unit and the plane of the loop-shaped wiring portion of the transmitting unit, there are a decrease in the conversion efficiency to power and an angle at which power cannot be converted. Specifically, there is a problem that power cannot be converted unless the magnetic field lines of the electromagnetic field formed on the transmitting side cross the loop-shaped wiring portion which is the receiving surface of the receiving unit (see FIG. 1). The technology of the above wireless power transfer system is disclosed in Patent Document 1.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the wireless power transfer technology described in Patent Document 1 does not address the problem of reduced power conversion efficiency due to the configuration angle of the transmitting and receiving units. Furthermore, if the receiving device in the receiving unit moves out of the range of the electromagnetic field formed by the transmitting unit due to the movement of the equipment it is installed in, power reception will naturally cease, power transfer will stop, and there is a problem in that stable operation of the equipment equipped with the receiving device becomes difficult. Furthermore, conventional wireless power transfer systems require the creation of new products with a receiver as the power source, resulting in high production costs and limited versatility. In particular, devices that use general batteries or rechargeable batteries that do not utilize wireless power transfer systems cannot be used as is if a wireless power transfer system is to be implemented. Furthermore, in devices that use conventional batteries and rechargeable batteries that do not employ a wireless power transfer system, it is naturally necessary to replace or recharge the battery once it is depleted, and removing the battery from the device is essential.

[0007] The present invention aims to solve the above problems and provide a receiving device in a wireless power transfer system that can always perform stable power conversion regardless of the angular position of the receiving unit relative to the transmitting unit. Furthermore, the present invention aims to enable the provision of a wireless power transfer system in many electrical appliances that use ordinary batteries without modifying their current form, by making the above-mentioned rechargeable battery replaceable with a commercially available battery. The present invention further aims to enable stable operation of equipment equipped with a receiving device even when the receiving device is outside the range of the electromagnetic field formed by the transmitting unit, by equipping the receiving device of the receiving unit with a rechargeable battery. Furthermore, this invention aims to provide a novel home appliance by taking advantage of the fact that the wireless power transfer system can remotely transmit power to the receiving device of the receiving unit and charge the rechargeable battery of the receiving device. [Means for solving the problem]

[0008] To address the above issues, the invention of claim 1 provides a wireless power transfer system, The receiver unit converts the electromagnetic field converted from power in the transmitter unit back into power within the electromagnetic field, wherein the receiver unit has at least two loop-shaped wiring sections, each of which is arranged at an angle to the others, and the magnetic field lines of the electromagnetic field formed by the transmitter unit always pass inside at least one of each loop-shaped wiring section, regardless of changes in the orientation of the receiver unit. The invention of claim 2 is further characterized in that the receiving unit has positive and negative electrodes arranged in a part of the loop-shaped wiring section, and the external dimensions and electrode position shape of the loop-shaped wiring section are the same as those of a commercially available battery or rechargeable battery. The invention of claim 3 is characterized in that, in the invention of claim 1, the receiving unit further comprises a rechargeable battery electrically connected to each loop-shaped wiring unit. The invention of claim 4 is further characterized in that the receiving unit has positive and negative electrodes arranged in a part of the loop-shaped wiring section, and the external dimensions and electrode position shape of the loop-shaped wiring section are the same as those of a commercially available battery or rechargeable battery. The invention of claim 5 is further characterized in that, in the invention of claim 3 or 4, the electrical appliance that is operated with a receiving device for a wireless power transfer system attached is housed in a space having a loop-shaped wiring section and a wireless power transfer function for the transmitting section after the electrical appliance has been operated. The invention of claim 6 is further characterized in that, in the invention of claim 3 or 4, the container in which an electrical appliance that is operated with a receiving device of a wireless power transfer system is housed after the operation of the electrical appliance is provided with a loop-shaped wiring section and has a wireless power transfer function of the transmitting section. The invention of claim 7 is further characterized in that, in the inventions of claims 1 to 4, the ON / OFF control of the receiving device is performed by turning the power of the transmitting device ON / OFF, or by moving the position of the transmitting device when the power is ON. [Effects of the Invention]

[0009] The present invention solves the problem in existing wireless power transfer systems where power conversion becomes impossible depending on the angular position of the receiving unit relative to the transmitting unit, and provides stable power conversion at all times regardless of the angular position of the receiving unit. Furthermore, since the external size and function of this receiver are identical to those of existing commercially available batteries, it can be easily used as a replacement for existing batteries. Furthermore, by adding a rechargeable battery function to the receiving device, even when it is outside the power conversion range, the power supply to the electrical device using it will not be interrupted by this rechargeable battery. Furthermore, when the battery runs out, there is no need to remove it from the appliance and replace it as with conventional batteries; simply placing the appliance within the range of the transmitter will automatically recharge it. In other words, products that use conventional dry cell batteries as their power source can be used within the range where they can receive the electromagnetic field from the transmitter, allowing them to continue using them without needing to replace the batteries. Moreover, if the storage box for the appliance is integrated with the transmitter, charging can begin simultaneously upon placement. Furthermore, the ability to charge the battery without removing it from the electrical appliance allows for the battery to be embedded in the product, enabling the creation of products with enhanced safety features, such as completely waterproof products. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram of an existing wireless power transfer system, where (a) shows the angle at which the receiving device can receive signals, and (b) shows the angle at which the receiving device cannot receive signals. [Figure 2] This is a schematic diagram of the wireless power transfer system of the first embodiment, where (a) shows the configuration of a typical receiving device, and (b) shows a configuration in which the external dimensions and electrode position shape of the receiving device are the same as those of a commercially available battery. [Figure 3] This is a schematic diagram of the receiving device of the wireless power transfer system of the second embodiment, where (a) shows the configuration of a typical receiving device, and (b) shows a configuration in which the external dimensions and electrode position shape of the receiving device are the same as those of a commercially available battery. [Figure 4]It is a schematic diagram of a wireless power transfer system according to a second embodiment. (a) shows a configuration in which a storage container of a receiving device is disposed within a transmission range of a transmitting device, and (b) shows a configuration in which the transmitting device is disposed in the storage container of the receiving device. [Figure 5] It is a schematic diagram of a fourth embodiment. [Figure 6] It is a schematic diagram of a fifth embodiment.

Mode for Carrying Out the Invention

[0011] Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. First, problems of an existing wireless power transfer system 100 will be described. In an existing wireless power transfer system 100, as shown in FIG. 1(a), when the angle formed by the plane formed by the loop-shaped wiring portion of the transmitting unit 10 and the plane formed by the loop-shaped wiring portion of the receiving unit 20 is 0 degrees, that is, when the two planes are parallel, the reception efficiency is maximized. As shown in FIG. 1(b), there is a phenomenon that when the angle formed by the two planes is 90 degrees, that is, perpendicular, the reception efficiency is minimized (reception is not possible). Qualitatively explained, this is because the magnetic force lines 10a of the electromagnetic field formed by the transmitting unit 10 pass through the inside of the loop-shaped wiring portion of the receiving unit 20 in the case of FIG. 1(a), while the magnetic force lines 10a do not pass through the inside of the loop-shaped wiring portion of the receiving unit 20 in the case of FIG. 1(b).

[0012] Next, the configuration of the first embodiment of the present invention will be described. As shown in Fig. 2(a), in the wireless power transfer system 100, it is a configuration of a receiving unit 30 that converts an electromagnetic field converted from power in the transmitting unit 10 into power within the electromagnetic field. The receiving unit 30 has two loop-shaped wiring portions A and B each configured in the same plane, and the planes to which the loop-shaped wiring portions A and B belong are arranged perpendicular to each other. The magnetic force lines 10a of the electromagnetic field formed by the transmitting unit 10 always pass inside at least one of the loop-shaped wiring portions A and B. In this embodiment, although the loop-shaped wiring portions A and B are both formed in a planar shape, the loop-shaped wiring portions do not necessarily have to be formed in a planar shape and may be formed in a curved surface shape (for example, a helical curved surface). Further, in this embodiment, two loop-shaped wiring portions A and B are provided. However, if there is no problem with the receiving function in the receiving unit 20 or no problem with reception efficiency in a configuration where only one loop-shaped wiring portion is provided depending on the positional relationship with the magnetic force lines 10a, etc., it may be configured to provide only one loop-shaped wiring portion. Regarding the conditions of the surfaces on which these loop-shaped wiring portions are formed and the conditions of the number of loop-shaped wiring portions installed, the same applies to all the following embodiments. Furthermore, as shown in Fig. 2(b), the receiving unit 30 is provided with positive and negative electrodes electrically connected to a part of the loop-shaped wiring portions A and B, and the outer size of this loop-shaped wiring portion and the shape of the positive and negative electrode positions are the same as those of a commercially available battery or cell. As is clear from the above description and the functions and effects of the present embodiment described below, the purpose of the configuration of the present embodiment is to ensure that the magnetic force lines 10a always stably pass inside the loop of any one of the loop-shaped wiring portions. Therefore, in this embodiment, two loop-shaped wiring portions A and B are provided. However, for example, in a configuration where only one loop-shaped wiring portion is provided, the surface on which the loop-shaped wiring portion is formed may be a helically twisted curved surface, etc., to achieve the purpose of the present embodiment.

[0013] Next, the functions and effects of the present embodiment will be described. In the receiving unit 30 of this embodiment, since the surfaces to which the two loop-shaped wiring sections A and B belong are orthogonal to each other, power conversion can always be performed stably regardless of the angular position relative to the transmitting unit 10, as long as it is within the range of the electromagnetic field formed by the transmitting unit 10, and power can be continuously supplied to the device housing the receiving unit 30 (for example, product 2 in Figure 4). Furthermore, the receiving unit 30 of this embodiment is equipped with positive and negative electrodes electrically connected to a portion of the loop-shaped wiring sections A and B. Since the external dimensions and the positions and shapes of the positive and negative electrodes of these loop-shaped wiring sections are identical to those of commercially available batteries, the receiving unit 30 can be used as a substitute for batteries in electrical appliances that use commercially available batteries, as long as it is within the range of an electromagnetic field.

[0014] Next, a second embodiment of the present invention will be described. As shown in Figure 3(b), the configuration of the receiving unit 30 in this embodiment is such that the external dimensions of the loop-shaped wiring section and the positions and shapes of the positive and negative electrodes are the same as those of a commercially available battery or rechargeable battery. Furthermore, a rechargeable battery 1, which is actually the same shape as a commercially available one, is installed in the section where this battery or rechargeable battery is housed. In this embodiment, the functions and effects are as follows, since the receiving unit 30, which in the first embodiment only had the function of supplying power, now also has a built-in rechargeable battery 1 and a charging function added. The device housing the receiving unit 30 (for example, product 2 in Figure 4) can maintain stable operation by using the power stored in the rechargeable battery 1, even when it temporarily moves outside the range of the electromagnetic field formed by the transmitting unit 10. In other words, since the rechargeable battery 1 of this embodiment has the same external dimensions, including the loop-shaped wiring sections A and B, and the same electrode position shape as commercially available batteries, general electrical devices that use commercially available batteries can be used by replacing the battery portion with the receiving device of this embodiment, which consists of a receiving unit 30 and a rechargeable battery 1, as long as they are within the range of the electromagnetic field formed by the transmitting unit 10 of the wireless power transfer system 100 (even if they are temporarily outside that range). In this case, the device housing the receiving unit 30 (for example, product 2 in Figure 4) is always automatically charged to the rechargeable battery 1 as long as it is within the range of the electromagnetic field, so there is no need to replace the battery.

[0015] Next, a third embodiment of the present invention will be described. First, the configuration of this embodiment will be described. In this embodiment, as shown in Figure 4, the battery-powered product 2, which houses the receiving unit 30 containing the rechargeable battery 1 of the first embodiment, is equipped with an electromagnetic field formation function for the transmitting unit 10 in the storage container 3 into which the product 2 is stored after operation. As shown in Figure 4, if product 2 is a model car, the storage box 3 has an AC power outlet and is equipped with the electromagnetic field forming function of the transmitting unit 10.

[0016] The function and effect of this embodiment is, firstly, that for electrical appliances that are operated using commercially available batteries, the receiving device 30, which incorporates the pre-charged rechargeable battery 1 of this embodiment, can be used instead of those commercially available batteries. Since the external size and electrode position shape are the same, it can be used without any problems. Furthermore, after operating product 2, storing it in the storage box 3 allows for automatic charging through the electromagnetic field formation function of the transmitter 10 of the wireless power transfer system 100, the conversion of power to the receiver 30, and the charging of the rechargeable battery 1. Therefore, there is no need to replace the battery of product 2.

[0017] This feature, which eliminates the need for battery replacement, will bring about a major transformation in the design of conventional battery-powered products 2. In other words, conventionally, all products using batteries, whether conventional or rechargeable, were designed with the assumption that the battery would need to be replaced. Removing and replacing the battery was an absolute prerequisite. However, with this embodiment, it has become possible to equip the storage container 3 with the transmitter 10 of the wireless power transfer system, and the product 2 with the receiver 30 and rechargeable battery 1, resulting in a configuration that has a built-in battery but does not require replacement. This has the effect of eliminating the need for battery replacement, which can be extremely difficult in devices designed with conventional battery replacement in mind. Furthermore, the design philosophy, which assumes that battery replacement will not be necessary, is expected to lead to the development of many groundbreaking new functions for products that use dry cell batteries.

[0018] Next, a fourth embodiment will be described. As shown in Figure 5, the configuration of this embodiment is used as a charger 4 that charges a commercially available rechargeable battery 1 or other battery using the power received by the receiving unit 30. In this embodiment, the transmitting unit 10 can be configured to have its function housed in the storage container 3, or, more broadly, to have the transmitting function of the wireless power transfer system 100 extend to the room, house, or entire area where the charger 4 is installed. By using the receiver unit 30 of this embodiment, for example, the indoor rechargeable battery 1 can be easily charged simply by turning the power of the transmitter unit 10 ON / OFF from outdoors.

[0019] Next, a fifth embodiment will be described. As shown in Figure 6, the ON / OFF switch for power transfer from the transmitter 10 to the receiver 30 is performed by adjusting the distance between the transmitter 10 and the outdoor receiver 30 while the indoor transmitter 10 is powered ON. Of course, as shown in Figures 6(a) and (b), the distance between the transmitter 10 and the receiver 30 can be set to a range where wireless power transfer is possible, and the ON / OFF switch for power transfer can be performed by turning the power of the transmitter 10 ON / OFF. However, as shown in Figures 6(c) and (d), the ON / OFF switch for power transfer can also be performed by adjusting the distance to the receiver 30 while the power of the transmitter 10 is ON. In this embodiment, the transmitting unit 10 is located indoors and the receiving unit 30 is located outdoors, separated by a shield. However, the wireless power transfer system of the present invention can be used in the same way as in this embodiment, regardless of the presence or absence of a shield, that is, even when there is no shield between the transmitting unit 10 and the receiving unit 30, and even in the general case where the spaces on both sides separated by the shield are not limited to indoors or outdoors. This embodiment shows an example of the wireless power transfer system of the present invention that can be used as long as the receiving unit 30 is included in the electromagnetic field generated by the transmitting unit 10. In other words, whether there is an obstruction or not, if the receiving unit 30 does not have a charging function, power can be transmitted and electrical appliances can be used across the distance, and if the receiving unit 30 has a charging function, power can be transmitted and electrical appliances can be used and charged, as described in other embodiments. According to the method of this embodiment, for example, it is possible to have a function that detects when the transmitting unit 10 and the receiving unit 30, which are both powered on, are within a predetermined distance of each other by turning the power transfer ON / OFF.

[0020] As explained above, the scope of application of the present invention is considered to be extremely broad. The following is a summary of the problems and solutions presented by the present invention. Conventional wireless power conduction systems have a problem in that their effectiveness is affected by the angle between the transmitter and receiver; for example, the power transfer force decreases when they are at a right angle. In contrast, the present invention provides at least two receiving loops that intersect at an angle, enabling reception from any angle relative to the transmitting unit. Furthermore, conventional wireless power conduction systems have the drawbacks of requiring the creation of a new product with a receiver as the power source, resulting in significant manufacturing costs and limited versatility. In contrast, the present invention features a receiver that has the same shape as commercially available dry cell batteries of various sizes, allowing it to be directly incorporated into devices that use existing dry cell batteries, thus enabling low cost and high versatility. Furthermore, conventional wireless power transfer systems had the problem that power could not be transferred once the transmission range was exceeded. In contrast, the present invention incorporates a rechargeable battery into the receiver, allowing it to be charged within the range of the transmitter, and enabling the use of the charged power even when it moves outside the range where it can transmit power after charging. Furthermore, commercially available dry cell batteries have the drawback of requiring the user to remove them from electrical appliances and replace them once they are depleted, which is inconvenient. In contrast, the present invention provides a receiving unit with the same shape as a dry cell battery (external shape and electrode position shape), allowing conventional electrical appliances to incorporate this receiving unit instead of a dry cell battery, thus enabling them to be used without battery replacement within the range of the transmitting unit. Furthermore, commercially available rechargeable batteries have the drawback of requiring users to remove them from the device, recharge them, and then reinsert them into the electrical appliance when the charge runs out. In contrast, the present invention incorporates a receiver with a charging function into the receiving unit, allowing it to be charged without removing it from the appliance, and enabling the appliance to be used regardless of whether it is within or outside the range of the transmitting unit. (When used outside the range of the transmitting unit, it can be used until the battery runs out.) Furthermore, as an application of the above solution, the present invention incorporates a receiver with a charging function into the receiving unit of an electrical appliance, and installs a transmitter in a container such as the storage box of the electrical appliance or in a storage location, thereby enabling the entire device to be charged without removing the rechargeable battery from the device. Furthermore, conventionally, there was a challenge in building a simple system that could turn electrical appliances installed inside a house on and off from outside. In contrast, the present invention incorporates a receiver unit of a wireless power transfer system into an electrical appliance, and enables the ON / OFF of the power supply of the transmitter unit from outdoors, thereby making it possible to construct a simple system that allows the power of an indoor electrical appliance to be turned ON / OFF from outdoors. [Explanation of symbols]

[0021] 1 rechargeable battery 2 Products using batteries 3 Storage containers 4 charger 10 Transmitter 10a Magnetic field lines 20 Receiver (existing) 30 Receiving unit (this embodiment) 100 Wireless Power Transfer Systems A, B wiring section

Claims

1. In wireless power transfer systems, The electromagnetic field converted from power in the transmitting section The configuration of the receiving unit that converts into power within the electromagnetic field, wherein the receiving unit is Each unit has at least two loop-shaped wiring sections, which are arranged at an angle to each other, and the magnetic field lines of the electromagnetic field formed by the transmitting unit always pass inside at least one of the loop-shaped wiring sections, regardless of changes in the orientation of the receiving unit. A receiving device for a wireless power transfer system, characterized by the following features.

2. The receiving device for a wireless power transfer system according to claim 1, characterized in that the receiving unit has positive and negative electrodes arranged in a part of the loop-shaped wiring section, and the external dimensions of the loop-shaped wiring section and the positional shape of the electrodes are the same as those of a commercially available battery or rechargeable battery.

3. The receiving device for a wireless power transfer system according to claim 1, characterized in that the receiving unit comprises a rechargeable battery electrically connected to each of the loop-shaped wiring units.

4. The receiving device for a wireless power transfer system according to claim 3, characterized in that the receiving unit has positive and negative electrodes arranged in a part of the loop-shaped wiring section, and the external dimensions of the loop-shaped wiring section and the positional shape of the electrodes are the same as those of a commercially available battery or power bank.

5. The receiving device for the wireless power transfer system according to claim 3 or 4, wherein the electrical appliance to which the receiving device for the wireless power transfer system is installed is, after the electrical appliance has been in operation, housed in the space of the transmitting unit that has the wireless power transfer function and is equipped with a loop-shaped wiring section.

6. The receiver for the wireless power transfer system according to claim 3 or 4, characterized in that the container in which an electrical appliance is stored after the operation of the electrical appliance is fitted with the receiver for the wireless power transfer system described above is provided with a loop-shaped wiring section and has the wireless power transfer function of the transmitting section described above.

7. A receiving device for a wireless power transfer system according to any one of claims 1 to 4, characterized in that the ON / OFF control of the receiving device is performed by turning the power of the transmitting device ON / OFF, or by moving the position of the transmitting device when the power is ON.

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