JP5656766B2 - Wireless communication system for rotating body - Google Patents

Description

  The present invention relates to a wireless communication system for a rotating body for performing wireless communication between the rotating body and a support portion that rotatably supports the rotating body.

  As a conventional wireless communication system for a rotating body of this type, a rotating side antenna provided on an inner peripheral surface of a rotating body (for example, a rotor of an in-wheel motor) and a fixed side provided for a support portion (for example, a vehicle body) An apparatus is known that performs wireless communication with an antenna and wirelessly transmits detection data of a sensor provided in a rotating body (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2005-304251 (paragraphs [0049] to [0054], [0071], FIG. 1)

  However, in the conventional wireless communication system for a rotating body described above, depending on the position of the rotating body, the position of the rotating side antenna may deviate from the radio wave receiving area from the fixed side antenna, and wireless communication may not be possible. It was. That is, in the conventional wireless communication system for a rotating body, stable wireless communication cannot be performed at all positions of the rotating body.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a wireless communication system for a rotating body capable of performing stable wireless communication at all positions of the rotating body.

The wireless communication system for a rotating body (100) according to the invention of claim 1 made to achieve the above object is fixed to a support portion (80) that rotatably supports the rotating body (60), and the rotating body ( 60) a fixed-side radio circuit (10) having a fixed-side antenna (11) facing the inner or outer peripheral surface, a sensor (40) fixed to the rotating body (60), and a fixed-side antenna (11). ) And a rotating antenna (23) fixed to the inner or outer peripheral surface of the rotating body (60) facing the motor, and operates with electric power generated by receiving radio waves from the fixed antenna (11). In the rotating body wireless communication system (100) including the rotating side wireless circuit (20) that wirelessly transmits the detection data of the sensor (40), the rotating side antenna (23) is included in the rotating body (60). On the tag (21) fixed to the circumferential surface or outer circumferential surface Provided, the tag (21) forms a fixed structure to extend the loop-shaped path (23A) over between the ends of the rotating antenna (23) the rotating body (60) half or more of the outer peripheral surface of the The reception area (R1) that can receive the radio wave from the fixed antenna (11) with the interval between both ends (23B, 23B) of the rotation antenna (23) in the circumferential direction of the rotating body (60). It is characterized in that it is smaller than the width of.

  According to a second aspect of the present invention, in the wireless communication system for a rotating body (100) according to the first aspect, the rotating body (60) is a rotor (60) of the rotating machine (50), and the sensor (40) is It is characterized in that it is directly fixed to a magnet (63) provided in the rotor (60) to detect temperature or magnetic flux intensity.

  According to a third aspect of the present invention, in the wireless communication system for a rotating body (100) according to the second aspect, the rotating machine (50) is an in-wheel motor (50) used as a driving source of a vehicle, and is a rotor. (60) has a cylindrical shape arranged outside the stator (51) of the in-wheel motor (50), and includes a nonmagnetic metal protective cover (64) on the outer peripheral surface. The sensor (40) The rotating antenna (23) is fixed to the outer peripheral surface of the protective cover (64) and is formed in the protective cover (64) so as to penetrate the protective cover (64). ) Through which the sensor (40) and the rotating antenna (23) are connected.

  According to a fourth aspect of the present invention, in the wireless communication system for a rotating body (100) according to the third aspect of the present invention, a rotating side antenna is provided on the protective cover (64) side of the loop (21A) of the tag (21). The magnetic sheet (25) for forming a part of the magnetic path of the electromagnetic field from the stationary antenna (11) penetrating the loop-shaped electric path (23A) of (23) is characterized.

The wireless communication system for a rotating body (100) according to the invention of claim 5 is fixed to a support portion that rotatably supports the rotating body (60) and faces the inner peripheral surface or the outer peripheral surface of the rotating body (60). A fixed-side radio circuit (10) having a fixed-side antenna (11), and a rotating-side tag antenna (23, 23) fixed to the inner peripheral surface or outer peripheral surface of the rotating body (60) facing the fixed-side antenna (11). In the wireless communication system for a rotating body (100) including the rotating side wireless circuit (20) having 123, 323), the rotating tag antenna (23, 123, 323) is connected to the inner peripheral surface of the rotating body (60) or It is characterized in that it is wound around half or more of the outer peripheral surface, and wireless communication is possible between the fixed-side wireless circuit (10) and the rotating-side wireless circuit (20) at all positions of the rotating body (60).
A sixth aspect of the present invention is the wireless communication system for a rotating body (100) according to the fifth aspect, wherein the rotating side tag antenna (323) is fixed to the inner peripheral surface or the outer peripheral surface of the rotating body (60). (21) and a plurality of loop antennas (323A, 323B) arranged in a line across both ends of the tag (21), and adjacent loop antennas (323A, 323B) are linked to each other. And is characterized in that one loop antenna (323A) is connected to the rotating side radio circuit (20).

[Invention of Claim 1]
According to the wireless communication system for a rotating body (100) of the first aspect of the present invention, the rotation-side antenna (23) provided in the rotation-side wireless circuit (20) has a loop-shaped electric circuit (23A) as a tag (21). It has the structure which extended and fixed between the both ends. Then, the tag (21) is wound around the inner circumference or the outer circumference of the rotating body (60) and more than half a circumference, and both end portions (23B, 23B) of the rotating antenna (23) in the circumferential direction of the rotating body (60). Is configured to be smaller than the width of the receiving region (R1) that can receive the radio wave from the fixed antenna (11). Thereby, irrespective of the position of the rotating body (60), stable wireless communication can be performed between the fixed antenna (11) and the rotating antenna (23). That is, reception performance can be improved at all positions of the rotating body (60). Then, wireless communication can be performed at an arbitrary timing while the rotating body (60) is rotating, and data detected by the sensor (40) can be acquired by the fixed-side wireless circuit (10).

[Invention of claim 2]
When the rotating machine (50) is operated in a high load state, a temperature increase of the magnet (63) and a decrease in magnetic flux intensity accompanying this may occur abruptly. For this reason, although the parts around the magnet (63) are not hot, the magnet (63) may be hot. According to the present invention, since the sensor (40) is directly fixed to the magnet (63) provided in the rotor (60), even if the temperature and magnetic flux intensity change suddenly, these temperature and magnetic flux can be obtained with high response. The intensity can be detected.

[Invention of claim 3]
According to the invention of claim 3, stable wireless communication is possible between the rotor (60) of the in-wheel motor (50) as a drive source of the vehicle and the vehicle body, and the temperature of the rotor (60). Alternatively, the magnetic flux intensity can be detected with a high response and transmitted to the vehicle body side.

[Invention of claim 4]
According to invention of Claim 4, the magnetic material sheet (25) arrange | positioned by the protective cover (64) side from the loop-shaped electric circuit (23A) among tags (21) is a loop shape of a rotation side antenna (23). Part of the magnetic path penetrating through the electric circuit (23A) of the non-magnetic metal protective cover (64), even when the rotation-side antenna (23) is provided on the outer peripheral surface, the fixed-side antenna (11) The radio wave from can be received reliably.

[Inventions of Claims 5 and 6]
According to the fifth and sixth aspects of the invention, wireless communication can be performed between the fixed-side radio circuit (10) and the rotary-side radio circuit (20) at all positions of the rotating body (60). That is, stable wireless communication is possible at all positions of the rotating body (60). Then, wireless communication is possible at an arbitrary timing while the rotating body (60) is rotating.

1 is a side sectional view of a motor-integrated drive wheel equipped with a wireless communication system for rotating bodies according to a first embodiment of the present invention. Top view of the rotor Block diagram of wireless communication system for rotating body Perspective view of rotor Partial enlarged view of the rotor The perspective view of the rotor provided with the IC tag which concerns on 2nd Embodiment

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a drive wheel 90 with a built-in motor provided in an electric vehicle. The motor built-in drive wheel 90 is supported by a vehicle main body 80 of the electric vehicle, and includes a wheel 70 and an outer rotor type in-wheel motor 50 disposed inside the wheel 70. The wheel 70 includes a tire 71 and a tire wheel 72, and the tire wheel 72 includes a rim 73 on which the tire 71 is mounted and a disk 74 that projects from the inner periphery of the rim 73.

  The in-wheel motor 50 includes a cylindrical stator 51 and a cylindrical rotor 60 disposed outside the stator 51.

  The stator 51 is fixed to a wheel support portion 81 having a cylindrical structure extending toward the wheel 70 in the vehicle main body 80. The stator 51 includes a cylindrical stator core 52 made of a silicon steel plate and a stator coil 53 wound around the stator core 52.

  As shown in FIG. 2, the rotor 60 includes a cylindrical rotor main body 69 and a plurality of permanent magnets 63 and 63 embedded in the rotor main body 69. The rotor body 69 includes a rotor yoke 61 made of laminated steel plates and a nonmagnetic metal (for example, aluminum) protective cover 64 fitted outside the rotor yoke 61.

  The permanent magnets 63, 63 are embedded in a ring shape along the circumferential direction of the rotor 60. Specifically, the rotor yoke 61 is formed with a plurality of magnet embedded holes 62, 62 along the circumferential direction, and plate-like permanent magnets 63, 63 are provided in the magnet embedded holes 62, 62, respectively. Has been inserted.

  As shown in FIG. 1, end plates 65A and 65B are fixed to both end surfaces in the axial direction of the rotor 60, and both end surfaces in the longitudinal direction of the permanent magnets 63 and 63 protrude from the end plates 65A and 65B. It has been applied.

  Of both end plates 65 </ b> A and 65 </ b> B, the end plate 65 </ b> A on the tire wheel 72 side is fixed to the disk 74 of the tire wheel 72. Thereby, the rotor 60 and the tire wheel 72 (wheel 70) can rotate integrally.

  The end plate 65 </ b> B on the vehicle body 80 side is supported outside the wheel support portion 81 via a bearing 76. An output shaft 66 stands from the center of the end plate 65 </ b> A on the tire wheel 72 side toward the vehicle body 80, and the output shaft 66 extends through the inside of the stator core 52 and the wheel support portion 81. . A bearing 67 is fitted between the outer peripheral surface of the output shaft 66 and the inner peripheral surface of the wheel support portion 81. With these bearings 67 and 76, the rotor 60 can be rotated outside the stator 51. A brake disc (not shown) is provided on the vehicle body 80 side of the output shaft 66.

  Now, the IC tag 20 (corresponding to the “rotation-side radio circuit” of the present invention) and the sensor 40 are attached to the rotor 60 of the in-wheel motor 50 described above, and the electric vehicle supports the motor-integrated drive wheels 90. The vehicle body 80 is attached with a reader / writer 10 (corresponding to the “fixed-side wireless circuit” of the present invention) that performs wireless communication with the IC tag 20. The IC tag 20, the reader / writer 10 and the sensor 40 constitute a wireless communication system 100 for a rotating body according to the present invention.

  As shown in FIG. 3, the reader / writer 10 includes a reader antenna 11 (corresponding to the “fixed antenna” of the present invention), a wave transmitting / receiving unit 12, and a control unit 13. The control unit 13 usually outputs a signal including a data transmission command from the reader antenna 11 as a radio wave by the transmission / reception unit 12. In response to this, the radio wave output from the IC tag 20 is received, and information included in the radio wave is acquired. At this time, the IC tag 20 obtains electric power necessary for operation from a radio wave by electromagnetic induction. The reader / writer 10 also performs wired or wireless communication with the host device 16 (for example, ECU) provided in the electric vehicle.

  The reader / writer 10 includes a transmitter / receiver 12 and a controller 13 with a reader antenna 11 exposed outside a main body 15 (see FIG. 1) in which a case is built. It corresponds to the “supporting part” of the invention. The reader antenna 11 is a so-called “loop antenna” in which a conducting wire is wound in a loop shape, and is arranged in an annular gap between the inner peripheral surface of the rim 73 of the tire wheel 72 and the outer peripheral surface of the rotor 60. Yes. As shown in FIG. 4, the loop surface surrounded by the loop-shaped conductor of the reader antenna 11 is disposed so as to face the outer peripheral surface of the rotor 60.

  As shown in FIG. 3, a sensor 40 is connected to the IC tag 20. The sensor 40 of this embodiment is a temperature sensor such as a thermistor or a resistance temperature detector, for example, and is directly fixed to an arbitrary permanent magnet 63 provided in the rotor 60 as shown in FIG.

  On the other hand, the IC tag 20 is fixed to the outer peripheral surface of the rotor 60 as shown in FIG. The IC tag 20 (specifically, an IC chip 22 described later) and the sensor 40 are connected by a wiring 41 as shown in FIG. The rotor 60 is formed with a wiring hole 68 extending through the protective cover 64 to the magnet embedding hole 62, and the wiring 41 is passed through the wiring hole 68.

  As shown in FIG. 4, the IC tag 20 includes an IC chip 22 and a tag antenna 23 (corresponding to the “rotation side antenna” of the present invention). As shown in FIG. 3, the IC chip 22 includes a memory 26, a control unit 27, a wave transmission / reception unit 28, and a rectification unit 29.

  The memory 26 is, for example, a nonvolatile memory (EEPROM), and stores detection data (temperature data) from the sensor 40.

  The rectifying unit 29 converts the AC voltage electromagnetically induced in the tag antenna 23 by the AC magnetic field of the radio wave received from the reader / writer 10 into a DC voltage and applies it to the control unit 27. As a result, the control unit 27 is activated to execute a predetermined program, and information included in the radio wave received by the tag antenna 23 is acquired through the transmission / reception unit 28. When the data transmission command is included in the information acquired at this time, the control unit 27 reads the detection data (temperature data) from the sensor 40 from the memory 26. Information including detection data is converted into a radio wave by the transmission / reception unit 28 and output from the tag antenna 23.

  The IC chip 22 and the tag antenna 23 are fixed to the tag main body 21. As shown in FIG. 4, the tag main body 21 has a strip shape that is substantially the same length as the circumferential length of the rotor 60. The tag main body 21 has a structure in which a flexible base sheet 24 and a magnetic sheet 25 are stacked, and the IC chip 22 and the tag antenna 23 are provided on the base sheet 24 (see FIG. 5). ).

  The tag antenna 23 is printed on the surface of the base sheet 24 with, for example, conductive ink. The tag antenna 23 has a rectangular or oval loop shape with a predetermined number of turns (one turn in this embodiment), and a loop-shaped electric circuit 23A extends between both end portions of the tag main body 21. It is fixed. The tag body 21 is wound around the outer peripheral surface of the rotor 60 almost once, and both end portions 23B and 23B of the tag antenna 23 are arranged close to each other in the circumferential direction.

  More specifically, as shown in FIG. 4, the electric path 23A of the tag antenna 23 extends away from the IC chip 22 toward both sides in the circumferential direction, and is folded back at a position about 180 degrees away from the IC chip 22 to each other. It extends to approach. And the space | interval of the both ends 23B and 23B of the tag antenna 23 which is a folding | returning part of electric circuit 23A is smaller than the width | variety of receiving area R1 which can receive the radio wave from the reader antenna 11 (refer FIG. 2).

  Here, it is more preferable that a cover sheet is stacked on the surface of the base sheet 24 on which the IC chip 22 and the tag antenna 23 are arranged to protect them.

  The magnetic sheet 25 of the tag main body 21 has a configuration in which a thin magnetic material having high magnetic permeability and electrical insulation is protected with a resin film. In a state where the IC tag 20 is wound around the outer peripheral surface of the rotor 60, the magnetic sheet 25 is disposed closer to the rotor 60 than the base sheet 24 on which the tag antenna 23 is printed. That is, the magnetic sheet 25 is disposed between the outer peripheral surface of the rotor 60 and the tag antenna 23.

  The magnetic sheet 25 forms a part of a magnetic path that penetrates the loop-shaped electric path 23A generated by the radio wave from the reader antenna 11, and generates eddy currents in the vicinity of the outer peripheral surface of the rotor 60 formed of a metal surface. Prevent occurrence. Thereby, even if the tag antenna 23 is disposed on the outer peripheral surface of the rotor 60 made of a nonmagnetic metal (in this embodiment, aluminum), radio waves are reliably transmitted and received between the tag antenna 23 and the reader antenna 11. Can wave.

  The above is the configuration of the present embodiment, and the operation of the present embodiment will be described below. When the start switch of the electric vehicle is turned on, the host device 16 is activated and outputs a data request command to the reader / writer 10 at a predetermined cycle. Then, the reader / writer 10 converts the information including the data transmission command into a radio wave by the transmission / reception unit 12 (on a carrier wave), and outputs it from the reader antenna 11. This radio wave reaches the wave receiving region R <b> 1 that is the portion facing the reader antenna 11 and the vicinity thereof on the outer peripheral surface of the rotor 60.

  The IC tag 20 provided on the outer peripheral surface of the rotor 60 receives the radio wave output from the reader / writer 10 by the tag antenna 23. The AC voltage electromagnetically induced in the tag antenna 23 by the radio wave AC magnetic field from the reader antenna 11 is converted into a DC voltage by the rectifier 29 and applied to the controller 27. As a result, the control unit 27 operates and the control unit 27 acquires information included in the radio wave received by the tag antenna 23 through the transmission / reception unit 28.

  When the “data transmission command” is included in the information acquired at this time, the control unit 27 reads the detection data (temperature data) from the sensor 40 from the memory 26 and transmits / receives information including the detection data. To the unit 28. The transmission / reception unit 28 converts the information including the detection data into a radio wave (on a carrier wave) and outputs it from the tag antenna 23. Note that the ID data of the IC tag 20 may be included in the information including the detection data.

  The radio wave output from the IC tag 20 is received by the reader antenna 11 of the reader / writer 10. And the transmission / reception part 12 decodes the information contained in a radio wave, and the control part 13 acquires the information. Further, the control unit 13 outputs the acquired information to the higher-level device 16.

  The host device 16 determines whether the temperature data acquired from the IC tag 20 is normal. And when it determines with it being abnormal, ie, when the temperature of the permanent magnet 63 becomes higher than preset temperature, the command (for example, instruction | command of an electric current limitation or forced cooling) for temperature rise suppression or cooling is given. Output.

  As described above, according to the wireless communication system 100 for a rotating body of the present embodiment, the tag antenna 23 provided in the IC tag 20 is provided over substantially the entire outer peripheral surface of the rotor 60. As a result, the magnetic flux of the radio wave from the reader antenna 11 passes through the loop-shaped electric path 23A of the tag antenna 23 regardless of the position of the rotor 60. Therefore, the radio wave is transmitted between the reader antenna 11 and the tag antenna 23. You can send and receive. That is, stable wireless communication can be performed at all positions of the rotor 60 between the rotor 60 of the in-wheel motor 50 and the vehicle main body 80. Then, the temperature of the permanent magnet 63 can be read by the reader / writer 10 by performing wireless communication at an arbitrary timing while the rotor 60 is rotating.

  In addition, according to the present embodiment, since the sensor 40 is directly fixed to the permanent magnet 63 of the rotor 60, even when the temperature of the permanent magnet 63 is rapidly increased by driving the in-wheel motor 50 in a high load state. The temperature of the permanent magnet 63 can be detected with a high response. Thereby, the abnormal heat generation of the permanent magnet 63 and the accompanying decrease in the magnetic flux intensity can be prevented.

[ Second Embodiment]
This second embodiment is shown in FIG. 6 , and the configuration of the tag antenna provided in the rotor 60 is different from that of the first embodiment. That is, the tag antenna 323 according to the present embodiment includes a plurality of first antenna elements 323A each having a rectangular loop shape connected to the transmission / reception unit 28 of the IC tag 20, a rectangular loop coil, and a capacitor. The first and second antenna elements 323A, 323B are arranged in a line over almost the entire circumference of the outer peripheral surface of the rotor 60. The first and second antenna elements 323A and 323B receive an alternating magnetic field from the reader antenna 11 and are inductively coupled to the reader antenna 11, and adjacent antenna elements 323A and 323B are inductively coupled in a chain manner. It has become. Note that the adjacent antenna elements 323A and 323B are preferably arranged as close to each other as possible, or arranged so as to partially overlap each other. Other configurations are the same as those in the first embodiment. Also according to the present embodiment, the same effects as those of the first embodiment can be obtained.

[Other Embodiments]
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be changed and implemented.

  (1) In the above embodiment, the rotor 60 of the rotating machine (motor) is illustrated as an example of the “rotating body” according to the present invention. However, a rotating body other than the rotor 60, for example, a vehicle tire, a tire wheel, or the like. The wireless communication system 100 for a rotating body of the present invention may be applied as a “rotating body”.

  (2) In the above embodiment, the in-wheel motor 50 used as a drive source of the vehicle is illustrated as an example of the “rotating machine” according to the present invention. However, the vehicle motor and the industrial motor other than the in-wheel motor 50 are exemplified. The wireless communication system 100 for a rotating body of the present invention may be applied to a motor for home appliances. Moreover, you may apply the radio | wireless communications system for rotary bodies of this invention to a generator.

  (3) In the above embodiment, the outer rotor type rotating machine (motor) is exemplified as an example of the “rotating machine” according to the present invention, but the inner rotor type rotating machine (motor) is used for the rotating body of the present invention. The wireless communication system 100 may be applied. In this case, the rotor may have a cylindrical structure, the IC tag 20 may be fixed to the inner peripheral surface, and the reader antenna 11 may be disposed so as to face the inner peripheral surface of the rotor.

  (4) In the above embodiment, the sensor 40 is fixed to the surface of the permanent magnet 63 of the rotor 60, but the sensor 40 may be embedded in the permanent magnet 63. Further, the sensor 40 may be embedded in the rotor yoke 61 or fixed to the outer peripheral surface of the rotor 60.

  (5) In the above embodiment, the sensor 40 fixed to the rotor 60 is a temperature sensor that detects the temperature of the permanent magnet 63, but may be a magnetic sensor (Hall element, magnetic impedance element, etc.) that detects magnetic flux intensity. . Further, an acceleration sensor, a pressure sensor, a vibration sensor, a strain sensor, or the like may be fixed to a rotating body other than the rotor 60.

  (6) In the above embodiment, the “passive type” IC tag 20 that generates electric power by receiving radio waves from the reader / writer 10 is illustrated, but the IC tag 20 charges the generated electric power. It is good also as a structure provided with the electrical storage part (what is called a "semi-passive type" IC tag).

  (7) In the above embodiment, the reader antenna 11 is disposed between the outer peripheral surface of the rotor 60 and the inner peripheral surface of the rim 73 of the tire wheel 72. However, the reader antenna 11 and the rim 73 in the vicinity thereof are arranged. You may arrange | position a magnetic body sheet | seat with high magnetic permeability and electrical insulation between the metal parts to contain. This makes it possible to make the magnetic sheet part of the magnetic path penetrating the reader antenna 11 and reliably prevent the generation of eddy currents due to the metal in the vicinity of the reader antenna 11.

10 Reader / Writer (Fixed-side radio circuit)
11 Reader antenna (fixed antenna)
20 IC tag (rotation side radio circuit)
21 Tag body (tag)
22 IC chip 23 Tag antenna (rotation side antenna, rotation side tag antenna)
23A Electric circuit 25 Magnetic material sheet 40 Sensor 50 In-wheel motor 51 Stator 60 Rotor 63 Permanent magnet (magnet)
64 Protective cover 68 Wiring hole 80 Vehicle body (supporting part)
DESCRIPTION OF SYMBOLS 90 Motor built-in drive wheel 100 Rotating body radio | wireless communications system 160 Rotating body R1 Reception area

Claims (6)

A fixed-side radio circuit having a fixed-side antenna (11) fixed to a support portion (80) that rotatably supports the rotating body (60) and facing the inner or outer peripheral surface of the rotating body (60) ( 10) and
A sensor (40) fixed to the rotating body (60);
It has a rotating side antenna (23) fixed to the inner peripheral surface or outer peripheral surface of the rotating body (60) facing the fixed side antenna (11), and receives radio waves from the fixed side antenna (11). In the wireless communication system for a rotating body (100), which is operated by the power generated by the wave and includes the rotation-side wireless circuit (20) that wirelessly transmits the detection data of the sensor (40),
The rotation-side antenna (23) is provided on a tag (21) fixed to an inner peripheral surface or an outer peripheral surface of the rotating body (60), and is looped between both end portions of the tag (21). The electric circuit (23A) is extended and fixed, and the rotation-side antenna (23) is wound around more than half a circumference of the outer peripheral surface of the rotating body (60) to rotate the rotating body (60) in the circumferential direction. For the rotating body characterized in that the distance between both ends (23B, 23B) of the side antenna (23) is smaller than the width of the receiving region (R1) that can receive the radio wave from the fixed side antenna (11). A wireless communication system (100).   The rotating body (60) is a rotor (60) of a rotating machine (50), and the sensor (40) is directly fixed to a magnet (63) provided in the rotor (60) to be subjected to temperature or magnetic flux. The wireless communication system (100) for a rotating body according to claim 1, wherein the strength is detected. The rotating machine (50) is an in-wheel motor (50) used as a drive source of a vehicle, and the rotor (60) is disposed outside a stator (51) of the in-wheel motor (50). And a protective cover (64) of non-magnetic metal on the outer peripheral surface,
The sensor (40) is fixed to the magnet (63) inside the protective cover (64),
The rotating antenna (23) is fixed to the outer peripheral surface of the protective cover (64),
3. The rotating body according to claim 2, wherein the sensor (40) and the rotating antenna (23) are connected through a wiring hole (68) formed through the protective cover (64). A wireless communication system (100).   The stationary antenna (23A) passing through the loop-shaped electric circuit (23A) of the rotating antenna (23) from the loop-shaped electric circuit (23A) to the protective cover (64) side of the tag (21). The wireless communication system (100) for a rotating body according to claim 3, further comprising a magnetic sheet (25) for forming a part of the magnetic path of the electromagnetic field from (11).   A fixed-side radio circuit (10) having a fixed-side antenna (11) fixed to a support portion that rotatably supports the rotating body (60) and facing the inner or outer peripheral surface of the rotating body (60); ,
  From the rotation side radio circuit (20) having the rotation side tag antenna (23, 123, 323) fixed to the inner peripheral surface or the outer peripheral surface of the rotating body (60) facing the fixed side antenna (11). In the wireless communication system for a rotating body (100),
  The rotation-side tag antenna (23, 123, 323) is wound around the inner circumferential surface or the outer circumferential surface of the rotation body (60) and more than half a circumference of the rotation body (60), and the fixed-side radio circuit (10 ) And the rotation-side wireless circuit (20), the wireless communication system for a rotating body (100). The rotation-side tag antenna (323) is arranged in a row across the tag (21) fixed to the inner peripheral surface or outer peripheral surface of the rotating body (60) and both ends of the tag (21). It has a plurality of loop antennas (323A, 323B), and is configured such that adjacent loop antennas (323A, 323B) are inductively coupled in a chain and one loop antenna (323A) The rotator wireless communication system (100) according to claim 5, wherein the rotator wireless communication system (100) is connected to the rotation-side wireless circuit (20).

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