Non-contact power supply system

Abstract

To efficiently execute power transmission by a non-contact power supply system.SOLUTION: A vehicle 10 has a setting system 20 for setting the propriety of vehicle use through radio communication between an on-vehicle vehicle side communication device 21 and a key side communication device 22 provided in a key member 16 for the vehicle. The non-contact power supply system includes a power transmitter 50. The power transmission part 50 has a power transmission device 51 provided in the vehicle 10 and including a power transmission coil 62, and a power reception device 52 provided in the key member 16 and including a power reception coil 53. The power transmission unit 50 executes power transmission from the power transmitting device 51 to the power receiving device 52 by non-contact power supply using the power transmitting coil 62 and the power receiving coil 53. The power transmission unit 50 executes the power transmission using a second frequency different from a first frequency used in the wireless communication.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] A setting system has been known in the past that sets whether or not to allow use of a vehicle through wireless communication between a vehicle-side communication device mounted on a vehicle such as an automobile and a key-side communication device provided on a key member for the vehicle (see Patent Document 1). In this type of setting system, for example, when a communication connection is established through wireless communication between the vehicle-side communication device and the key-side communication device, authentication of the key member is performed. Then, once authentication of the key member is successful, use of the vehicle, such as unlocking the doors and starting the engine, is permitted.

[0003] It has also been proposed to equip a vehicle with a contactless power supply system that contactlessly supplies power to a mobile device carried by a user, such as a smartphone. In the contactless power supply system of Patent Document 1, the vehicle is provided with a power transmitting device including a power transmitting coil for transmitting power. The mobile device is provided with a power receiving device including a power receiving coil for receiving power. In this contactless power supply system, power is transmitted from the on-board power transmitting device to the power receiving device of the mobile device by contactless power supply using an electromagnetic induction method using the power transmitting coil and the power receiving coil.

[0004] When a setting system and a contactless power transfer system are mounted on a vehicle, there is a risk of interference between radio waves used for wireless communication in the setting system and radio waves generated during power transfer in the contactless power transfer system. In Patent Document 1, to avoid a deterioration in the functionality of each system due to such radio wave interference, power transfer in the contactless power transfer system is not performed when wireless communication in the setting system is performed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2012 / 000646 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, when wireless communication is being performed in the setting system, power transfer in the contactless power transfer system is disabled, which reduces the opportunities for power transfer from the power transmitting device to the power receiving device. In this respect, there is room for improvement in the contactless power transfer system. [Means for solving the problem]

[0007] Various aspects of the device for solving the above problems will be described. [Aspect 1] A contactless power transfer system applied to a vehicle having a setting system that sets whether or not the vehicle can be used through wireless communication between an on-board vehicle-side communication device and a key-side communication device provided on a key member for the vehicle, the system including a power transmitting device provided on the vehicle and including a power transmitting coil, and a power receiving device provided on the key member and including a power receiving coil, and further including a power transmitting unit that performs power transfer from the power transmitting device to the power receiving device, the power transmitting unit performing the power transfer by contactless power transfer using the power transmitting coil and the power receiving coil, and performing the power transfer using a second frequency different from the first frequency used in the wireless communication.

[0008] According to the above configuration, the first frequency used in wireless communication by the setting system is different from the second frequency used in power transmission by the contactless power transfer system. Therefore, even when power transmission by the contactless power transfer system and wireless communication by the setting system are performed simultaneously, interference between radio waves generated during power transmission and radio signals (radio waves) transmitted and received during wireless communication can be suppressed. Therefore, power transmission by the contactless power transfer system and wireless communication by the setting system can be performed simultaneously while suppressing degradation of the functionality of each system due to radio wave interference. Therefore, compared to when power transmission is not performed during wireless communication, the opportunities for performing power transmission by the contactless power transfer system can be increased, and power transmission can be performed efficiently.

[0009] [Aspect 2] The wireless power transfer system according to [Aspect 1], wherein the setting system defines a vehicle-side transmission frequency and a key-side transmission frequency as the first frequency, which are different from each other, and transmits a wireless signal from the vehicle-side communication device to the key-side communication device using the vehicle-side transmission frequency and transmits a wireless signal from the key-side communication device to the vehicle-side communication device using the key-side transmission frequency, and the second frequency is a frequency between the vehicle-side transmission frequency and the key-side transmission frequency.

[0010] According to the above configuration, the second frequency used in power transmission can be set to a frequency included in the setting range of the first frequency used in wireless communication, i.e., a setting range with one of the vehicle-side transmission frequency and the key-side transmission frequency as its upper limit and the other as its lower limit. This prevents the second frequency from becoming too high or too low, making it easy to realize a power transmission unit that uses the second frequency.

[0011] [Aspect 3] A contactless power supply system according to [Aspect 1] or [Aspect 2], wherein the second frequency is set to a frequency in the range of 5 megahertz or more and 15 megahertz or less.

[0012] As in the above configuration, the second frequency is preferably set to a frequency included in the range of 5 megahertz or more and 15 megahertz or less. [Aspect 4] The contactless power supply system according to any one of [Aspect 1] to [Aspect 3], further comprising a light emitting portion provided on the key member that emits light when the power receiving device receives power.

[0013] In the above configuration, when the key member is brought into the vehicle and the power receiving device of the key member starts receiving power, the light emitting part of the key member lights up. Therefore, if the key member is lost inside the vehicle, the key member can be easily found by visually checking the lit key member.

[0014] [Aspect 5] The contactless power supply system according to [Aspect 4], wherein the light emitting unit changes its light emitting state depending on the amount of power received per unit time by the power receiving device. In the above configuration, even if the operating condition of the power transmitting device is the same, the amount of power received by the power receiving device per unit time varies depending on the distance between the power transmitting device and the power receiving device and the attitude of the power receiving device relative to the power transmitting device. With the above configuration, the light-emitting state of the light-emitting part changes depending on the amount of power received by the power receiving device per unit time, and this light-emitting state can be used as an indicator for knowing the position and attitude of the key member that improves power transmission efficiency.

[0015] [Aspect 6] A contactless power supply system as described in [Aspect 4] or [Aspect 5], wherein the key member has a storage battery that serves as the power source for the key member, and the power receiving device has, as the power receiving coil, a first coil that is connected only to the storage battery out of the storage battery and the light-emitting unit, and a second coil that is connected only to the light-emitting unit out of the storage battery and the light-emitting unit.

[0016] According to the above configuration, the storage battery can be charged by receiving power through a first coil connected to the storage battery. Furthermore, the light-emitting unit connected to the second coil can be illuminated by receiving power through a second coil not connected to the storage battery, without relying on power stored in the storage battery. Furthermore, because the light-emitting unit is not connected to the first coil and the storage battery, power is not supplied to the light-emitting unit when the power receiving device is not receiving power, such as when the key member is located away from the vehicle. In this case, the light-emitting unit can be turned off without adding any special configuration for turning it off.

[0017] [Aspect 7] The contactless power supply system according to any one of [Aspect 1] to [Aspect 6], wherein the number of turns of the power transmission coil is "3" or less. According to the above configuration, by reducing the number of turns of the power transmission coil, the inductance of the coil can be reduced, allowing the frequency used for power transmission to be increased. Furthermore, by reducing the number of turns of the power transmission coil, the length of the power transmission coil can be shortened and the thickness of the coil can be reduced, which makes it possible to install the power transmission coil on the back surface of an interior component, and thus allows the power transmission coil to be installed in a thin and narrow space with a high degree of freedom.

[0018] [Aspect 8] A contactless power supply system according to any one of [Aspect 1] to [Aspect 7], wherein the power transmission coil is attached to the rear surface of a top wall that forms the upper part of the outer wall of the center console.

[0019] According to the above configuration, when the key member is placed on the center console or when an occupant is sitting in a seat adjacent to the center console while holding the key member, power can be transmitted from the power transmitting device to the power receiving device using the power transmitting coil. [Effects of the Invention]

[0020] According to the present invention, power can be efficiently transferred from a power transmitting device to a power receiving device. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a schematic diagram showing a schematic configuration of a vehicle to which a contactless power supply system according to an embodiment is applied. [Figure 2] FIG. 2 is a block diagram showing a schematic configuration of the contactless power supply system according to the embodiment. [Figure 3] FIG. 3 is a schematic diagram showing the power transmitting device and the first power receiving unit. [Figure 4] FIG. 4 is a schematic diagram showing the power transmitting device and the second power receiving unit. [Figure 5] FIG. 5 is a perspective view of the key member. [Figure 6] 6 is a cross-sectional view of the key member taken along line 6-6 in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0022] An embodiment of a contactless power supply system will be described below. First, a vehicle 10 to which the non-contact system of this embodiment is applied will be described. As shown in Fig. 1, a driver's seat 12R and a passenger seat 12L are provided in the front of a passenger compartment 11 of a vehicle 10, aligned in the vehicle width direction. A driver's door 13R is provided to the right of the driver's seat 12R, and a passenger's door 13L is provided to the left of the passenger's seat 12L. A center console 14 is provided between the driver's seat 12R and the passenger's seat 12L.

[0023] The vehicle 10 is provided with an electronic control device (hereinafter referred to as a vehicle ECU 17) including, for example, a microcomputer. A locking device 15R that switches between locking and unlocking the driver's door 13R and a locking device 15L that switches between locking and unlocking the passenger's door 13L are connected to the vehicle ECU 17. The vehicle ECU 17 executes various controls related to vehicle control, such as operation control of the locking devices 15R and 15L and vehicle start control for starting the vehicle 10.

[0024] The vehicle 10 has a setting system 20 that sets whether or not the vehicle can be used through wireless communication between a vehicle-side communication device 21 and a key-side communication device 22. <Key-side communication device 22> The setting system 20 has a vehicle key member 16. The key member 16 is a device that is carried by the user of the vehicle 10 when the vehicle 10 is in use, and transmits a signal containing ID information corresponding to the user (hereinafter, referred to as an ID signal) to the vehicle 10.

[0025] As shown in FIG. 2, the key member 16 includes a key transmitting unit 31 and a key receiving unit 32 as the key-side communication device 22. The key member 16 also includes an electronic control unit (key ECU 33) such as a microcomputer. A unique ID signal is stored in advance in a memory 35 of the key ECU 33. The key ECU 33 controls the operation of the key transmitting unit 31 and the key receiving unit 32. The key transmitting unit 31 transmits a response signal including the ID signal using ultra-high frequency (UHF), specifically a frequency of 315.00 megahertz (hereinafter referred to as the key-side transmission frequency). The key receiving unit 32 receives a request signal using low frequency (LF), specifically a frequency of 134 kilohertz. The request signal is stored in the memory 35 of the key ECU 33.

[0026] <Vehicle-side communication device 21> The vehicle 10 has a total of five wireless communication devices as the vehicle-side communication device 21: two exterior transmitters 41R and 41L, one interior transmitter 42, and two vehicle receivers 43R and 43L.

[0027] The two exterior transmitters 41R, 41L output request signals to the outside of the vehicle 10. Each exterior transmitter 41R, 41L uses a long wave LF, specifically a frequency of 134.00 kilohertz, to output the request signal. One of the two exterior transmitters 41R, 41L (exterior transmitter 41R) is provided in front of the driver's door 13R on the vehicle body. The exterior transmitter 41R transmits the request signal mainly to the vicinity of the driver's door 13R outside the vehicle. The remaining one of the two exterior transmitters 41R, 41L (exterior transmitter 41L) is provided in front of the passenger door 13L on the vehicle body. The exterior transmitter 41L transmits the request signal mainly to the vicinity of the passenger door 13L outside the vehicle.

[0028] The interior transmitter 42 outputs a request signal toward the interior of the vehicle compartment 11. When outputting the request signal, the interior transmitter 42 uses a long wave LF, specifically a frequency of 134.00 kHz (hereinafter referred to as the vehicle-side transmission frequency). The interior transmitter 42 is provided on the floor of the vehicle 10.

[0029] In this embodiment, the vehicle-side transmission frequency used to output (transmit) the request signal and the key-side transmission frequency used to output (transmit) the response signal correspond to the first frequency used in the wireless communication. In this embodiment, the vehicle-side transmission frequency (134.00 kilohertz) and the key-side transmission frequency (315.00 megahertz), which are different from each other, are defined as the first frequency.

[0030] The two vehicle receiving units 43R, 43L receive the response signal transmitted from the key transmitting unit 31 of the key member 16. One of the two vehicle receiving units 43R, 43L (vehicle receiving unit 43R) is provided in front of the driver's door 13R on the vehicle body. The vehicle receiving unit 43R's reception range for the response signal is mainly around the driver's door 13R. The remaining one of the two vehicle receiving units 43R, 43L (vehicle receiving unit 43L) is provided in front of the passenger door 13L on the vehicle body. The vehicle receiving unit 43L's reception range for the response signal is mainly around the passenger door 13L.

[0031] The vehicle 10 is provided with an electronic control device (hereinafter referred to as a verification ECU 44) including a microcomputer or the like. The verification ECU 44 is configured to be able to communicate with the vehicle ECU 17. Two exterior transmitters 41R, 41L, one interior transmitter 42, and two vehicle receivers 43R, 43L are connected to the verification ECU 44. The verification ECU 44 receives response signals received by the vehicle receivers 43R, 43L.

[0032] The setting system 20 of this embodiment operates as follows. In the setting system 20, request signals are transmitted from the two exterior transmitters 41R, 41L and the interior transmitter 42 at appropriate timing (e.g., at a predetermined interval). Therefore, when a user carrying the key member 16 approaches or enters the vehicle 10, the key receiver 32 of the key member 16 receives the request signal. In response, the key transmitter 31 of the key member 16 transmits a response signal. When this response signal is received by at least one of the two vehicle receivers 43R, 43L, the ID signal included in the received response signal is compared with the ID signal stored in the memory 45 of the verification ECU 44. This determines whether the ID information (user) is registered in advance in the verification ECU 44. In this manner, the setting system 20 of this embodiment authenticates the key member 16. Once the key member 16 is authenticated, the user is permitted to use the vehicle 10, for example, unlock the doors 13R, 13L, start the engine, and so on.

[0033] The contactless power transfer system of this embodiment has a power transfer unit 50. The power transfer unit 50 has a power transfer device 51 provided in the vehicle 10 and including a power transfer coil 62, and a power receiving device 52 provided in the key member 16 and including a power receiving coil 53. The power transfer unit 50 transfers power from the power transfer device 51 to the power receiving device 52 by contactless power transfer using the power transfer coil 62 and the power receiving coil 53, based on magnetic field resonance.

[0034] <Power transmission device 51> 2 and 3, the power transmitting device 51 has a capacitor 61 and the power transmitting coil 62. The capacitor 61 and the power transmitting coil 62 constitute a power transmitting-side resonator 63 in the contactless power transfer system. In this embodiment, the power transmitting coil 62 is made of a copper wire with a wire diameter of 0.1 square millimeters, and the number of turns of the power transmitting coil 62 is 1.

[0035] 1, a top wall 141 that forms the upper part of the outer wall of the center console 14 is provided with a recess 142 that is recessed downward in the center. This recess 142 is provided to allow items such as a key member 16 to be placed therein. The power transmission coil 62 has a substantially rectangular ring shape and is attached to the back surface of the recess 142 in the top wall 141 of the center console 14 so that its axis extends in the vertical direction. In this embodiment, for example, the length of the power transmission coil 62 in the vehicle width direction is 0.15 meters, and the length in the front-rear direction of the vehicle 10 is 0.20 meters.

[0036] 2 and 3, the power transmitting device 51 has a control unit 64 with a built-in switching circuit. In the power transmitting device 51, an on-board DC power supply 18 and a resonator 63 are connected via the control unit 64. The power transmitting device 51 has an electronic control unit (hereinafter referred to as a power transmitting ECU 65) formed of, for example, a microcomputer. The power transmitting ECU 65 controls the operation of the control unit 64. The control unit 64 generates a trapezoidal wave voltage with a predetermined period through operation control of the switching circuit and applies the generated voltage to the resonator 63. This causes a sinusoidal wave current to flow through the power transmitting coil 62 of the resonator 63.

[0037] In this embodiment, the power transmitting device 51 transmits power to the power receiving device 52 using high frequency (HF), specifically, a frequency of 5.00 MHz or more and 15.00 MHz or less. The power transmitting device 51 transmits power to the power receiving device 52 using, specifically, a frequency of 6.78 MHz. In this embodiment, the frequency of 5.00 MHz or more and 15.00 MHz or less, specifically, the frequency of 6.78 MHz, corresponds to a second frequency used for power transmission from the power transmitting device 51 to the power receiving device 52. In this embodiment, the second frequency is a frequency between the vehicle-side transmission frequency (134.00 kHz) and the key-side transmission frequency (315.00 MHz).

[0038] <Power receiving device 52> The power receiving device 52 is provided in the key member 16 . As shown in FIGS. 5 and 6, the key member 16 has a case portion 70 and a holding portion 76.

[0039] The case 70 has a substantially pentagonal box shape in plan view. The case 70 has a lower wall 71, an intermediate portion 72, and an upper wall 73. The lower wall 71 constitutes the bottom wall of the case 70 and the bottom-wall-side portion of the peripheral wall, and is substantially pentagonal in plan view. The lower wall 71 is made of an opaque resin material (e.g., a black resin material). The upper wall 73 constitutes the portion forming the lid of the case 70 and the lid-side portion of the peripheral wall, and is substantially pentagonal in plan view. The upper wall 73 is made of an opaque resin material (e.g., a black resin material). The intermediate portion 72 constitutes the portion of the peripheral wall of the case 70 between the lower wall 71 and the upper wall 73, and is substantially pentagonal in plan view. The intermediate portion 72 is made of a colorless, transparent or colored, transparent resin material and is transparent to visible light. The case portion 70 has a structure in which an intermediate portion 72 is sandwiched between an upper wall portion 73 and a lower wall portion 71. In the case portion 70, the outer peripheral surface of the intermediate portion 72 forms part of the outer surface of the peripheral wall of the case portion 70.

[0040] As shown in FIG. 6 , a light-emitting element 74 is provided in the case portion 70. The light-emitting element 74 is configured, for example, by a light-emitting diode. The light-emitting element 74 is provided inside the case portion 70 so as to emit light toward the inner circumferential surface of the intermediate portion 72. In this embodiment, the light emitted by the light-emitting element 74 is diffused as it passes through the intermediate portion 72, causing substantially the entire intermediate portion 72 to light up. The key member 16 is configured so that, when the light-emitting element 74 emits light, a portion of the outer surface of the case portion 70, more specifically, the outer circumferential surface of the intermediate portion 72, lights up. In this embodiment, the intermediate portion 72 and the light-emitting element 74 form a light-emitting portion 75.

[0041] 5 and 6, the retaining portion 76 is L-shaped in plan view and is integrated with the outer surface of the case portion 70. More specifically, the retaining portion 76 is provided integrally with the case portion 70 such that the inner surface of the L-shaped portion and the outer surface of the case portion 70 form an annular shape.

[0042] As shown in Figure 6, a storage battery 77 is housed inside the key member 16. The storage battery 77 is a secondary battery, and serves as the power source for the key member 16 (more specifically, the key transmitting unit 3 [see Figure 1], the key receiving unit 32, and the power receiving device 52).

[0043] In this embodiment, the power receiving device 52 is configured with two power receiving devices (specifically, a first power receiving unit 521 and a second power receiving unit 522). The power received by the first power receiving unit 521 is supplied to the storage battery 77 of the key member 16. On the other hand, the power received by the second power receiving unit 522 is supplied to the light emitting unit 75 of the key member 16, specifically the light emitting element 74.

[0044] <First power receiving unit 521> 2 and 3, the first power receiving unit 521 has a first capacitor 81 and one of the power receiving coils 53 (hereinafter referred to as the first coil 82). The first capacitor 81 and the first coil 82 constitute one of the power receiving side resonators (hereinafter referred to as the first resonator 83) in the contactless power transfer system. The first coil 82 is made of copper wire with a wire diameter of 0.1 square millimeters, and the number of turns of the first coil 82 is 1.

[0045] The first power receiving unit 521 has a first rectifying unit 84 that converts the sinusoidal current flowing through the first resonator 83 (more specifically, the first coil 82) into DC current. The first rectifying unit 84 is configured to include a rectifying circuit having a diode. In the first power receiving unit 521, the first resonator 83 and the storage battery 77 are connected via the first rectifying unit 84. Of the storage battery 77 and the light emitting unit 75, the first coil 82 is connected only to the storage battery 77. In this embodiment, the DC power converted by the first rectifying unit 84 is supplied to the storage battery 77, and the storage battery 77 is charged.

[0046] <Second power receiving unit 522> As shown in Figures 2 and 4, the second power receiving unit 522 has a second capacitor 91 and one of the power receiving coils 53 (hereinafter referred to as the second coil 92). The second capacitor 91 and the second coil 92 form one of the power receiving side resonators (hereinafter referred to as the second resonator 93) in the wireless power feeding system. The second coil 92 is made of copper wire with a wire diameter of 0.1 square millimeters. The second coil 92 has one turn.

[0047] 5 and 6, in this embodiment, the first coil 82 and the second coil 92 have substantially the same shape. The first coil 82 and the second coil 92 are arranged so that their axes coincide with each other and overlap in the direction in which the axes extend.

[0048] As shown in FIGS. 2 and 4, the second power receiving unit 522 has a second rectifier 94 that converts a sinusoidal current flowing through the second resonator 93 (more specifically, the second coil 92) into a direct current. The second rectifier 94 is configured to include a rectifier circuit having a diode. In the second power receiving unit 522, the second resonator 93 and the light emitting unit 75 are connected via the second rectifier 94. Of the storage battery 77 and the light emitting unit 75, the second coil 92 is connected only to the light emitting unit 75. In this embodiment, the direct current power converted by the second rectifier 94 is supplied to the light emitting unit 75, causing the light emitting unit 75 to emit light.

[0049] <Operation of this embodiment> The operation of this embodiment will be described. In the contactless power transfer system of this embodiment, when the power transmission ECU 65 controls the control unit 64, more specifically, the operation of the switching circuit, a sinusoidal current flows through the power transmission coil 62. On the other hand, when the user places the key member 16 in the recess 142 of the center console 14, the first coil 82 and the second coil 92 of the key member 16 are positioned near the power transmission coil 62 of the power transmission device 51.

[0050] As a result, the resonator 63 of the power transmitting device 51 and the first resonator 83 of the first power receiving unit 521 are electromagnetically coupled in a resonant state, and the high-frequency power (more specifically, a sinusoidal current) supplied to the resonator 63 of the power transmitting device 51 is transmitted to the first resonator 83 of the key member 16. The high-frequency power transmitted to the first resonator 83 of the key member 16 is then converted into DC power by the first rectifier 84 of the first power receiving unit 521 and supplied to the storage battery 77. At this time, the storage battery 77 begins to be charged.

[0051] Also, at this time, the resonator 63 of the power transmitting device 51 and the second resonator 93 of the second power receiving unit 522 are electromagnetically coupled in a resonant state. As a result, the high-frequency power (more specifically, a sinusoidal current) supplied to the resonator 63 of the power transmitting device 51 is transmitted to the second resonator 93 of the key member 16. The high-frequency power transmitted to the second resonator 93 of the key member 16 is then converted to DC power by the second rectifier 94 of the second power receiving unit 522 and supplied to the light-emitting unit 75, more specifically, the light-emitting element 74. At this time, the light-emitting unit 75 emits light. As described above, in this embodiment, the light-emitting unit 75 emits light when the second power receiving unit 522 receives power. Moreover, the light-emitting state of the light-emitting unit 75 changes depending on the amount of power received per unit time by the second power receiving unit 522. In detail, the greater the amount of power received per unit time by the second power receiving unit 522, the greater the DC power converted by the second rectifying unit 94 and supplied to the light emitting unit 75, causing the light emitting unit 75 to emit light more brightly.

[0052] In the contactless power transfer system of this embodiment, the resonators 63, 83, 93 can be oscillated at a high frequency by reducing the inductance of the coils 62, 82, 92 and the capacitance of the capacitors 61, 81, 91. Specifically, reducing the number of turns of the coils 62, 82, 92 reduces the inductance of the coils 62, 82, 92, making it possible to oscillate the resonators 63, 83, 93 at a high frequency. Furthermore, if the number of turns of the coils 62, 82, 92 can be reduced to sufficiently reduce the inductance of the coils 62, 82, 92, it is not necessary to reduce the capacitance of the capacitors 61, 81, 91 to oscillate at a high frequency. In this case, the capacitance of the capacitors 61, 81, 91 can be prevented from becoming too small, allowing the capacitors 61, 81, 91 to have a realistic capacitance that is easily available. Furthermore, when the number of turns of the coils 62, 82, 92 is reduced, the length of the coils 62, 82, 92 is also reduced, which allows for greater freedom in arranging the coils 62, 82, 92 in the thin and narrow spaces inside the center console 14 and the key member 16. In light of this situation, in this embodiment, the number of turns of the coils 62, 82, 92 is set to "1".

[0053] Furthermore, the inventors have assumed that a system configuration that satisfies all of the following (Condition 1) to (Condition 5) is an appropriate system configuration for installing a contactless power supply system in the vehicle interior 11.

[0054] (Condition 1) The maximum length of the power transmission coil 62 in a direction perpendicular to its axis is equal to or greater than 0.15 meters and equal to or less than 1.00 meters. (Condition 2) The number of turns of the power transmission coil 62 is "3" or less.

[0055] (Condition 3) The capacitors 61, 81, and 91 that constitute the resonators 63, 83, and 93 have a realistic capacitance that is easily available. (Condition 4) The wire diameter of the power transmission coil 62 is 0.1 square millimeters.

[0056] (Condition 5) When the distance between the power transmitting device 51 and the power receiving device 52 is 0.40 meters or less, power of 5 watts or more and 20 watts or less can be transmitted from the power transmitting device 51 to the power receiving device 52.

[0057] As a result of various experiments and simulations conducted by the inventors, the following has been found: By setting the second frequency used for power transmission from power transmitting device 51 to power receiving device 52 to a frequency not less than 5.00 MHz and not more than 15.00 MHz, it is possible to realize a system configuration that satisfies all of the above (Condition 1) to (Condition 5). In light of this, in this embodiment, the second frequency is set to a frequency not less than 5.00 MHz and not more than 15.00 MHz, specifically, a frequency of 6.78 MHz.

[0058] <Effects of this embodiment> The effects of this embodiment will be described. (1) Vehicle 10 has setting system 20 that sets whether or not vehicle use is permitted through wireless communication between vehicle-side communication device 21 mounted on vehicle 10 and key-side communication device 22 provided on key member 16 for the vehicle. The contactless power supply system includes power transmission unit 50. Power transmission unit 50 has power transmission device 51 provided on vehicle 10 and including power transmission coil 62, and power reception device 52 provided on key member 16 and including power reception coil 53. Power transmission unit 50 transmits power from power transmission device 51 to power reception device 52 by contactless power supply using power transmission coil 62 and power reception coil 53. Power transmission unit 50 transmits the power using a second frequency that is different from the first frequency used in the wireless communication.

[0059] According to the above configuration, the first frequency (315.00 MHz, 134.00 kHz) used in wireless communication by the setting system 20 is different from the second frequency (6.78 MHz) used in power transmission by the contactless power transfer system. Therefore, even when power transmission by the power transmission unit 50 of the contactless power transfer system and wireless communication by the setting system 20 are performed simultaneously, interference between radio waves generated during power transmission and radio signals (radio waves) transmitted and received during wireless communication can be suppressed. Therefore, power transmission by the contactless power transfer system and wireless communication by the setting system 20 can be performed simultaneously while suppressing degradation of the functionality of each system due to radio wave interference. Therefore, compared to a case where power transmission is not performed during wireless communication, the opportunities for performing power transmission by the contactless power transfer system are increased, and the power transmission can be performed efficiently.

[0060] (2) The setting system 20 defines a vehicle-side transmission frequency and a key-side transmission frequency, which are different from each other, as the first frequency to be used in the wireless communication. A request signal is transmitted from the vehicle-side communication device 21 to the key-side communication device 22 using the vehicle-side transmission frequency. A response signal is transmitted from the key-side communication device 22 to the vehicle-side communication device 21 using the key-side transmission frequency. A second frequency to be used in power transmission from the power transmitting device 51 to the power receiving device 52 is a frequency between the vehicle-side transmission frequency and the key-side transmission frequency.

[0061] According to the above configuration, the second frequency used in the power transmission can be set to a frequency included in the setting range of the first frequency used in the wireless communication, i.e., a setting range having the key-side transmission frequency as its upper limit and the vehicle-side transmission frequency as its lower limit. This prevents the second frequency from becoming too high or too low, making it easy to realize the power transmission unit 50 that uses the second frequency.

[0062] (3) The second frequency is set to a frequency in the range of 5.00 megahertz or more and 15.00 megahertz or less. This makes it possible to realize a system configuration that is suitable for installing a contactless power supply system in the vehicle interior 11, which is the system configuration envisioned by the inventors.

[0063] (4) The key member 16 has a light emitting portion 75 that emits light when the power receiving device 52 receives power. In the above configuration, when the key member 16 is brought into the vehicle 10 and the power receiving device 52 of the key member 16 begins to receive power, the light emitting portion 75 of the key member 16 begins to emit light. Therefore, if the key member 16 is lost inside the vehicle 10, the key member 16 can be easily found by visually checking the illuminated key member 16.

[0064] (5) The light emitting section 75 changes its light emitting state in accordance with the amount of power received by the power receiving device 52 per unit time. Here, even if the operating condition of the power transmitting device 51 is the same, the amount of power received by the power receiving device 52 per unit time varies depending on the distance between the power transmitting device 51 and the power receiving device 52 and the attitude of the power receiving device 52 relative to the power transmitting device 51. According to the above configuration, the light emitting state of the light emitting unit 75 changes depending on the amount of power received by the power receiving device 52 per unit time, and therefore this light emitting state can be used as an index for knowing the position and attitude of the key member 16 that improves the efficiency of power transmission.

[0065] (6) The key member 16 has a storage battery 77 that serves as a power source for the key member 16. The power receiving device 52 has, as the power receiving coil 53, a first coil 82 connected only to the storage battery 77 out of the storage battery 77 and the light-emitting unit 75, and a second coil 92 connected only to the light-emitting unit 75 out of the storage battery 77 and the light-emitting unit 75.

[0066] According to the above configuration, the storage battery 77 can be charged by power received through the first coil 82 connected to the storage battery 77. Moreover, the light-emitting unit 75, specifically the light-emitting element 74, connected to the second coil 92 can be illuminated by power received through the second coil 92, which is not connected to the storage battery 77, without relying on power stored in the storage battery 77. Furthermore, because the light-emitting unit 75 is not connected to the first coil 82 and the storage battery 77, when the second power receiving unit 522 including the second coil 92 is not receiving power, such as when the key member 16 is located away from the vehicle 10, power is not supplied to the light-emitting unit 75. In this case, the light-emitting unit 75 can be turned off without adding any special configuration for turning off the light-emitting unit 75.

[0067] (7) The number of turns of the power transmission coil 62 is "1". According to the above configuration, by reducing the number of turns of the power transmission coil 62, the inductance of the power transmission coil 62 can be reduced, and therefore the second frequency used in power transmission can be set to a higher frequency. Furthermore, by reducing the number of turns of the power transmission coil 62, the length of the power transmission coil 62 can be shortened, and the thickness of the power transmission coil 62 can be reduced. This allows the power transmission coil 62 to be provided on the back surface of an interior component (for example, the center console 14), and thus allows the power transmission coil 62 to be provided in a thin, narrow space with a high degree of freedom.

[0068] (8) The power transmission coil 62 is attached to the rear surface of the top wall 141 that forms the upper part of the outer wall of the center console 14. According to the above configuration, when the key member 16 is placed in the recess 142 of the center console 14, power can be transmitted from the power transmitting device 51 to the power receiving device 52 using the power transmitting coil 62. Also, when the user is seated in a seat adjacent to the center console 14 (driver's seat 12R or passenger seat 12L) while holding the key member 16, power can be transmitted from the power transmitting device 51 to the power receiving device 52 using the power transmitting coil 62.

[0069] <Example of change> The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other within the scope of technical compatibility.

[0070] The second frequency can be any frequency, such as 13.56 MHz, as long as it is different from the first frequency used in the wireless communication. The second frequency can also be a frequency less than 5.00 MHz or a frequency higher than 15.00 MHz. In order to realize the system configuration envisioned by the inventors and suitable for installing a wireless power transfer system in the vehicle interior 11, it is preferable that the second frequency be a frequency equal to or greater than 5.00 MHz and equal to or less than 15.00 MHz.

[0071] As long as the first frequency (vehicle-side transmission frequency and key-side transmission frequency) used in the wireless communication is different from the second frequency used in the power transmission, the vehicle-side transmission frequency and the key-side transmission frequency can be changed as desired. The vehicle-side transmission frequency may be set to a frequency different from 134.00 kHz and to a long-wave LF frequency, for example, a frequency in the range from 100.00 kHz to 150.00 kHz. The key-side transmission frequency may be set to a frequency different from 315.00 MHz and to an ultra-high-frequency UHF frequency, for example, a frequency in the range from 300.00 MHz to 400.00 MHz.

[0072] The number of turns of the power transmission coil 62 can be changed as desired, for example, to two or three. However, if the resonator 63 can be made to oscillate at the second frequency and the power transmission coil 62 can be provided inside the vehicle interior 11, the number of turns of the power transmission coil 62 can also be set to four or more.

[0073] The number of turns of the first coil 82 and the second coil 92 can be changed as desired, such as to 2 or 3. However, as long as the first resonator 83 and the second resonator 93 can be made to oscillate at the second frequency and the first coil 82 and the second coil 92 can be provided inside the key member 16, the number of turns of the first coil 82 and the second coil 92 can also be set to 4 or more.

[0074] The wire diameter of the power transmission coil 62 and the wire diameter of the power reception coil 53 are not limited to 0.1 square millimeters, but can be changed arbitrarily, for example, to 0.2 square millimeters.

[0075] The location where the power transmission coil 62 is attached can be changed as desired. For example, the power transmission coil 62 can be attached to the back surface of the side wall of the center console 14, or to the outer surface of the center console 14. The power transmission coil 62 can also be attached to an interior part other than the center console 14. Examples of such interior parts include the instrument panel, center cluster, and door trim. If the power transmission coil 62 is provided on the door trim, the light-emitting portion 75 of the key member 16 can be used as a so-called welcome lamp to provide hospitality when getting in and out of the vehicle.

[0076] The shape and size of the power receiving coil 53 can be changed as desired. For example, the power receiving coil 53 can be formed into a circular ring shape or an elliptical ring shape. The maximum length of the power receiving coil 53 in the direction perpendicular to its axis can also be set to less than 0.15 meters or greater than 1.00 meters.

[0077] Instead of lighting the light-emitting unit 75 with power received from the second power receiving unit 522, the light-emitting unit 75 may be lighted with power received from the first power receiving unit 521 or power stored in the storage battery 77. For example, the power receiving device 52 may be configured so that, when power reception by the first power receiving unit 521 is detected, power for lighting the light-emitting element 74 is supplied from the storage battery 77. With this configuration, the light-emitting unit 75 of the key member 16 lights up when power is received by the power receiving device 52, more specifically, the first power receiving unit 521, but does not light up when power is not received by the first power receiving unit 521. In the above configuration, it is also possible to detect the amount of power received per unit time by the first power receiving unit 521 and change the light-emitting state of the light-emitting unit 75 depending on the detected amount of power received. In the above configuration, the key ECU 33 may perform control for detecting the amount of power received by the first power receiving unit 521 and control for making the light emitting unit 75 emit light.

[0078] Instead of making the light-emitting unit 75 glow brighter as the amount of power received per unit time by the second power receiving unit 522 increases, the light color of the light-emitting unit 75 may be changed according to the amount of power received per unit time by the second power receiving unit 522. Alternatively, the light-emitting state of the light-emitting unit 75 may be changed in the following order as the amount of power received per unit time by the second power receiving unit 522 increases: an off state where the light-emitting unit 75 is turned off, a flashing state where the light-emitting unit 75 flashes, and a flashing state where the light-emitting unit 75 is always lit. In short, it is only necessary to be able to change the light-emitting state of the light-emitting unit 75 according to the amount of power received per unit time by the second power receiving unit 522.

[0079] The light-emitting unit 75 is not limited to one including the intermediate portion 72 and the light-emitting element 74, and any structure can be used. For example, the light-emitting unit 75 may be configured with a through-hole provided in the case portion 70 and a light-emitting element 74 provided inside the case portion 70 so as to emit light toward the through-hole. Alternatively, the light-emitting unit 75 may be configured with a light-emitting element 74 provided on the outer surface of the case portion 70. The key point is that it is sufficient that the light-emitting unit 75, which forms part of the outer surface of the key member 16, can be illuminated when the power receiving device 52 receives power.

[0080] The second power receiving unit 522 and the light emitting unit 75 may be omitted. [Explanation of symbols]

[0081] 10...Vehicle 11...Vehicle compartment 12R...Driver's seat 12L…Passenger seat 13R...Driver's door 13L...Passenger door 14...Center console 141...Ceiling wall 142...recess 15R, 15L...locking device 16...Key member 17...Vehicle ECU 18…DC power supply 20...Settings system 21...Vehicle-side communication device 22...Key side communication device 31...Key transmission unit 32...Key receiver 33...Key ECU 35…Memory 41R, 41L...External transmitter 42...In-car transmitter 43R, 43L... Vehicle receiving unit 44…Check ECU 45...Memory 50...Power transmission section 51...Power transmission device 52...Power receiving device 521...First power receiving section 522...Second power receiving section 53...Receiving coil 61...Capacitor 62...Transmission coil 63...Resonator 64...Control unit 65...Power transmission ECU 70...Case section 71…Lower wall part 72...Middle section 73...Top wall part 74...Light emitting element 75...Light emitting part 76...Holding part 77...Storage battery 81...First capacitor 82...1st coil 83...1st resonator 84...1st rectifier 91...Second capacitor 92...Second coil 93…Second resonator 94…Second rectifier

Claims

1. The present invention is applied to a vehicle having a setting system for setting whether or not a vehicle can be used through wireless communication between an on-board vehicle-side communication device and a key-side communication device provided on a vehicle key member, a power transmitting device provided in the vehicle and including a power transmitting coil; and a power receiving device provided in the key member and including a power receiving coil, and a power transmitting unit configured to transmit power from the power transmitting device to the power receiving device; the power transmission unit performs the power transmission by contactless power supply using the power transmitting coil and the power receiving coil, and performs the power transmission using a second frequency different from a first frequency used in the wireless communication. Contactless power supply system.

2. The setting system includes: The first frequency is defined as a vehicle-side transmission frequency and a key-side transmission frequency, which are different from each other; and a vehicle-side communication device that transmits a radio signal to the key-side communication device using the vehicle-side transmission frequency, and a key-side communication device that transmits a radio signal to the vehicle-side communication device using the key-side transmission frequency; the second frequency is a frequency between the vehicle-side transmission frequency and the key-side transmission frequency; The contactless power supply system according to claim 1 .

3. The second frequency is set to a frequency included in the range of 5 MHz or more and 15 MHz or less. The contactless power supply system according to claim 1 or 2.

4. a light-emitting portion provided on the key member that emits light when the power receiving device receives power; The contactless power supply system according to claim 1 .

5. The light emitting unit changes its light emitting state in accordance with the amount of power received per unit time by the power receiving device. The contactless power supply system according to claim 4 .

6. The key member has a storage battery that serves as a power source for the key member, The power receiving device has, as the power receiving coil, a first coil connected only to the storage battery out of the storage battery and the light-emitting unit, and a second coil connected only to the light-emitting unit out of the storage battery and the light-emitting unit. The contactless power supply system according to claim 4 or 5.

7. The number of turns of the power transmission coil is "3" or less. The contactless power supply system according to claim 1 or 2.

8. The power transmission coil is attached to the rear surface of a top wall that forms an upper part of an outer wall of the center console. The contactless power supply system according to claim 1 or 2.

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