Abstract:
An electromagnetic induction-type connector for feeding electric power or a signal by a mutual induction action, includes a first connector, including a first core member which has a primary-side core and a primary-side coil, a second connector, including a second core member which has a secondary-side core and a secondary-side coil, the second core member producing an induction electromotive force in accordance with the first core member, and at least one of a first metal case and a second metal case. The first metal case is directly contacted with the first core member, and includes a receiving portion receiving a circuit board to which the primary-side coil is electrically connected and includes a contact portion contacting with a connector mounting portion. The second metal case is directly contacted with the second core member, and includes a receiving portion receiving a circuit board to which the secondly-side coil is electrically connected and includes a contact portion contacting with a connector mounting portion. A heat produced in the first core member and the second core member by the mutual induction action is radiated to the connector mounting portion through the contact portion.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates to an electromagnetic induction-type connector in which two members of a vehicle are brought into proximity to each other so as to feed electric power or a signal from one of the two members to the other by mutual induction.  
           [0002]    One well-known electromagnetic induction-type connector of this kind is used for supplying electric power between two members such as a car body and a door of a vehicle. More specifically, a first connector  4  of an electromagnetic induction-type connector is provided at a boarding port  3  in a car body  2  of a vehicle  1 , as shown in FIGS. 13 and 14. A second connector  6  of the electromagnetic induction-type connector is mounted on a door  5  for opening and closing the boarding port  3 .  
           [0003]    The first connector  4  is provided with a guide mechanism  9  including a recess  7  and a moving base  8 . A primary core  10  is supported by this guide mechanism  9  so as to slide (in directions of opening and closing of the door  5 ). Coil springs  11  are provided between the bottom of the recess  7  and the moving base  8 . Further, an annular permanent magnet  12  is mounted on that side of the moving base  8  on which the primary core  10  is mounted.  
           [0004]    The primary core  10  includes a disk portion  13 , fixedly secured to the moving base  8 , and a cylindrical portion  14  formed on and projecting from a central portion of the disk portion  13 . A primary coil  15 , including a winding of a wire, is wound around the cylindrical portion  14 .  
           [0005]    The second connector  6  includes a secondary core  18  having a cylindrical wall  16  and a bottom wall  17 . A secondary coil  19  is provided on an inner face of the cylindrical wall  16 , and this secondary coil  19  has an internal space, and the cylindrical portion  14  of the primary core  10  and the primary coil  15  can be inserted into and withdrawn from this internal space. A permanent magnet  20 , similar to the permanent magnet  12  of the first connector  4 , is provided at the second connector  6 , and is disposed around an open end or edge of the cylindrical wall  16  in closely-spaced relation thereto.  
           [0006]    In the above construction, when the door  5  is closed relative to the car body  2 , the primary core  10  and the secondary core  18  abut against each other. The permanent magnets  12  and  20  attract each other, and the primary core  10  and the secondary core  18  are coupled or joined together in close proximity to each other. As a result, mutual induction is produced between the primary coil  15  and the secondary coil  19 , so that electric power begins to be supplied from the car body  2  to the door  5 .  
           [0007]    In the electromagnetic induction-type connector, heat is generated by mutual induction, and therefore this connector has several problems described below.  
           [0008]    First, when the connector is installed at a position where a person touches it, the increase of the temperature of the cores and coils must be suppressed in order to secure safety, and therefore there is encountered a problem that it is impossible to supply a large amount of electric power. Secondly, a temperature control device (protection circuit) is needed for suppressing the increase of the temperature of the cores and coils, and also the electromagnetic induction-type connector must be formed, using a heat-resistant material, which invites a problem that this affects the cost.  
           [0009]    Incidentally, the Applicant of the present application has made an attempt to deal with the above problems by providing radiation fins on the electromagnetic induction-type connector. However, this attempt has drawbacks that the provision of the radiation fins increases the space and weight and that the resultant product is expensive (by the addition of the radiation fins). Therefore, this attempt has not been adopted.  
         SUMMARY OF THE INVENTION  
         [0010]    It is therefore a first object of the present invention to provide an electromagnetic induction-type connector having such a heat radiation structure that a large amount of electric power can be supplied, and also the increase of the cost can be suppressed. Second object is to provide an electromagnetic induction-type connector provided with the type of heat radiation structure which can suppress the increase of the space and weight.  
           [0011]    In order to achieve the above object, according to the present invention, there is provided an electromagnetic induction-type connector for feeding electric power or a signal by a mutual induction action, comprising:  
           [0012]    a first connector, including a first core member which has a primary-side core and a primary-side coil;  
           [0013]    a second connector, including a second core member which has a secondary-side core and a secondary-side coil, the second core member producing an induction electromotive force in accordance with the first core member; and  
           [0014]    at least one of a first metal case and a second metal case,  
           [0015]    wherein the first metal case is directly contacted with the first core member, and includes a receiving portion receiving a circuit board to which the primary-side coil is electrically connected and includes a contact portion contacting with a connector mounting portion;  
           [0016]    wherein the second metal case is directly contacted with the second core member, and includes a receiving portion receiving a circuit board to which the secondly-side coil is electrically connected and includes a contact portion contacting with a connector mounting portion; and  
           [0017]    wherein a heat produced in the first core member and the second core member by the mutual induction action is radiated to the connector mounting portion through the contact portion.  
           [0018]    In the above configuration, when the two members on which the first connector and the second connector is provided respectively are brought into proximity to each other, the first and second connectors are brought into proximity to or abut with each other. In this condition, when the primary-side coil of the first connector is excited, an induction electromotive force is produced in the second connector, thereby supplying electric power or transmitting a signal. Heat, produced by the mutual induction, is radiated to the directly-connected metal case, and is discharged to the connector mounting portion via the contact portion of the metal case.  
           [0019]    Therefore, the increase of the temperature of the core and coil can be suppressed during the supply of the electric power or during the transmission of the signal. Therefore, there is achieved an advantage that a large amount of electric power can be supplied. And besides, in the invention, the fine temperature control for suppressing the increase of the temperature of the coil and core is not necessary, and an inexpensive material can be used. Therefore, there is achieved an advantage that the increase of the cost can be suppressed. Furthermore, in the invention, the heat radiation can be effected, utilizing the case for receiving the circuit board. Therefore, the increase of the space and weight can be suppressed, and also the need for the provision of additional parts is obviated, thereby achieving an advantage that the increase of the cost can be suppressed.  
           [0020]    Preferably, a thermal conductive filler is filled in a gap between the primary-side core and the primary-side coil.  
           [0021]    Preferably, wherein a thermal conductive filler is filled in a gap between the secondary-side core and the secondary-side coil.  
           [0022]    In the above configuration, the heat, produced in the primary side and the secondary side coil, is radiated to the core via the filler. Then, the heat, is transferred to the metal case, and is discharged to the corresponding connector mounting portion via the contact portion. Thanks to the provision of the filler, the heat transfer between the core and the coil is effected efficiently.  
           [0023]    Preferably, the first metal case has a thermal conductive portion directly contacting the primary-side coil.  
           [0024]    Preferably, the second metal case has a thermal conductive portion directly contacting the secondary-side coil.  
           [0025]    In the above configurations, the heat, produced in the coils, is radiated also to the thermal conductive portion of the metal case held in direct contact with the coils. The heat transfer is effected efficiently by the thermal conductive portion.  
           [0026]    Preferably, a waterproof and heat radiation sheet is provided on the contact portion so that the sheet is held between the contact portion and the connector mounting portion.  
           [0027]    In the above configuration, a waterproof seal is formed between the contact portion of the metal case and the connector mounting portion while maintaining a heat-radiating ability.  
           [0028]    Preferably, the contact portion is fixed on the connector mounting portion by a connector fixing member.  
           [0029]    In the above configuration, the contact portion of the metal case, together with the electromagnetic induction-type connector, is fixed to the corresponding connector mounting portion in such a manner that the contact portion is held between the connector fixing portion and the connector mounting portion. The contact portion is always held in contact with the connector mounting portion so as to positively radiate the heat.  
           [0030]    Preferably, a electronic part mounted on the circuit board is contacted with the first metal case.  
           [0031]    In the above configuration, the heat, produced in the electronic part on the circuit board, is radiated to the metal case, and is discharged to the corresponding connector mounting portion via the contact portion of this metal case. Namely, there is achieved the advantage that heat, produced in the electronic parts which generates heat on the circuit board, is discharged to the corresponding connector mounting portion, thus suppressing the temperature rise due to other factor. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0032]    The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein:  
         [0033]    [0033]FIG. 1 is a cross-sectional view showing one preferred embodiment of an electromagnetic induction-type connector of the present invention;  
         [0034]    [0034]FIG. 2 is an exploded, perspective view of a first connector;  
         [0035]    [0035]FIG. 3 is a front-elevational view of the first connector;  
         [0036]    [0036]FIG. 4 is a rear view of the first connector;  
         [0037]    [0037]FIG. 5 is a side-elevational view of the first connector;  
         [0038]    [0038]FIG. 6 is a cross-sectional view taken along the line A-A of FIG. 3;  
         [0039]    [0039]FIG. 7 is a cross-sectional view taken along the line B-B of FIG. 3;  
         [0040]    [0040]FIG. 8 is a cross-sectional view taken along the line C-C of FIG. 3 (That portion within a circle is an enlarged, cross-sectional view of an important portion);  
         [0041]    [0041]FIG. 9 is a cross-sectional view showing a modified example of the electromagnetic induction-type connector;  
         [0042]    [0042]FIG. 10 is a rear view of a first connector shown in FIG. 9;  
         [0043]    [0043]FIG. 11 is a side-elevational view of the first connector shown in FIG. 9;  
         [0044]    [0044]FIG. 12 is a block diagram showing one example of an electric power supply system for a vehicle provided with the electromagnetic induction-type connectors shown in FIG. 1;  
         [0045]    [0045]FIG. 13 is a perspective view showing a side portion of a related vehicle;  
         [0046]    [0046]FIG. 14 is a cross-sectional view of a related electromagnetic induction-type connector; 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0047]    A preferred embodiment of the present invention will now be described with reference to the drawings.  
         [0048]    [0048]FIG. 1 is a cross-sectional view showing one preferred embodiment of an electromagnetic induction-type connector of the present invention. FIG. 2 is an exploded, perspective view of a first connector, FIG. 3 is a front-elevational view of the first connector, FIG. 4 is a rear view of the first connector, FIG. 5 is a side-elevational view of the first connector, FIG. 6 is a cross-sectional view taken along the line A-A of FIG. 3, FIG. 7 is a cross-sectional view taken along the line B-B of FIG. 3, and FIG. 8 is a cross-sectional view taken along the line C-C of FIG. 3 (That portion within a circle is an enlarged, cross-sectional view of an important portion).  
         [0049]    In FIGS.  1  to  8 , reference numeral  21  denotes the electromagnetic induction-type connector. This electromagnetic induction-type connector  21  includes the first connector  23  provided at a boarding port  22  in a car body of a vehicle, and a second connector  25  provided at a peripheral edge portion  24  of a door of the vehicle. The electromagnetic induction-type connector  21  is so constructed that electric power can be supplied (or a signal can be transmitted) from the car body to the door by mutual induction.  
         [0050]    The first connector  23  includes a first core member  26 , and a main case  27  provided at a front side of the first core member  26 . A primary coil oscillation drive control device  28  provided at a rear side of the first core member  26 . The first connector  23  is fixedly secured to a generally hole-like connector mounting portion  29 , formed at the boarding port  22 , by suitable fixing member (bolts in this embodiment).  
         [0051]    The first core member  26  includes a primary core (primary-side core)  30 , a primary coil (primary-side core)  31  received in the primary core  30 , and a thermally-conductive filler  32  filled in a gap between the primary core  30  and the primary coil  31 . The primary core  30  is formed, for example, by sintering ferrite powder, and this primary core  30  has an annular groove  32  of a channel-shaped cross-section formed in one side (face) thereof. The other side (face)  34  of the primary core  30  is formed into a flat face for intimate contact with an aluminum case  42  described later. The primary coil  31  is formed by winding a wire, and this primary coil  31  is so formed as to be received in the annular groove  32 . For example, STYCAST 2850FY epoxy casting resin (produced by Emerson &amp; Cumming) is used as the thermally-conductive filler  32 . The filler  32  is filled in order to efficiently transfer heat, produced in the primary coil  31 , to the primary core  30 . Reference numeral  35  denotes a connection portion extending outwardly from the primary coil  31 .  
         [0052]    The main case  27  is molded of an insulative synthetic resin (insulator). The main case  27  includes a generally cap-like coupling portion  36  covering the one side and peripheral face of the first core member  26  in a watertight manner, and a flange  38  having a pair of connector fixing portions  37 . The coupling portion  36  is fixedly secured to the first core member  26  by an adhesive or the like, and serves to protect the first core member  26  and also to reduce an impact upon contact. When the door is closed, a coupling portion  36  (described later) of the second connector  25  is brought into close proximity to (or into contact with) the coupling portion  36  of the first connector. In this embodiment, the coupling portion  36  is formed and located such that it projects beyond the boarding port  22  (although it is not limited to this arrangement). A fixing screw hole  39  is formed in the coupling portion  36 . Bolt passage holes  40  each for the passage of a bolt (not shown) therethrough are formed through the connector fixing portions  37 , respectively.  
         [0053]    The primary coil oscillation drive control device  28  includes a circuit board  41  for controlling the excitation of the primary coil  31 , and the aluminum case  42  (It is not limited to aluminum, and may be any other suitable metal in so far as it has good thermal conductivity.) which receives and fixes the circuit board  41 , and is connected directly to the first core member  26  to function as radiating means. The connecting portion  35  of the primary coil  31  is connected to a predetermined portion of the circuit board  41  (The connected condition is not shown). A plurality of FETs (Field-Effect-Transistors) which generates a heat are mounted on the circuit board  41 . Part of each of the FETs  43  contacts the aluminum casing  42 , and is fixedly secured thereto. Heat, generated in each of the FETs  43 , is transferred to the aluminum case  42 , and is radiated therefrom.  
         [0054]    The aluminum case  42  includes a case body  44 , and a cover  45  attached to this case body  44 . The case body  44  includes a bottom wall  46 , a pair of side walls  47 , and a core member-fixing wall  48 . The side walls  47  are formed respectively at opposite (right and left) side edges of the bottom wall  46 . The core member-fixing wall  48  is formed at a front edge of the bottom wall  46 . The casing body  44  is formed by these walls. A plurality of projections  49  are formed on each of the side walls  47 , and the circuit board  41  is fixed by these projections  49  as shown in the drawings. A receiving portion  50  for the circuit board  41  is formed within the aluminum case  42 . Reference numeral  51  denotes bolts for fixing the plurality of FETs  43  to one side wall  47 .  
         [0055]    The core member-fixing wall  48  corresponds in shape to the flange  38  of the main case  27 , and is a size smaller than this flange  38 . The core member-fixing wall  48  includes a core member-direct connection portion  52 , a contact portion  53 , and bolt relief portions  54 . The core member-direct connection portion  52  is formed into a flat face so as to intimately contact the other side (face)  34  of the primary core  30 . A bolt passage hole  56  for the passage of a fixing bolt  55  therethrough is formed through a central portion of the core member-direct connection portion  52 . The core member-direct connection portion  52  is fixedly secured to the coupling portion  36  by the bolt  55  threaded into a screw hole  39  formed in the coupling portion  36 . A pair of thermal conductive portions  57  for direct contact with the primary coil  31  are formed respectively at opposite (right and left) sides of the core member-direct connection portion  52 . In this embodiment, the thermal conductive portions  57  are formed by stamping and raising part of the core member-direct connection portion  52  (However, the formation is not limited to this method. The provision of the thermal conductive portions  57  is optional. It is preferred to provide these in order to achieve the efficient heat transfer.). Reference numerals  58  denotes a through hole through which the connection portion  35  of the primary coil  31  extends into the receiving portion  50 .  
         [0056]    The contact portion  53  is formed into a flat face so as to be held in contact with (preferably in intimate contact with) a peripheral edge portion of the connector mounting portion  29 . The contact portion  53  serves to discharge the heat, transferred to the aluminum case  42 , to the connector mounting portion  29 . Naturally, it is preferred to increase the area of the contact portion  53  as much as possible. The contact portion  53  is formed immediately adjacent to the bolt relief portions  54 , and is adapted to be held between the pair of connector fixing portions  37  of the main case  27  and the peripheral edge portion of the connector mounting portion  29  (The contact portion  53 , when fixed, positively contacts the peripheral edge portion of the connector mounting portion  29 . Heat radiation is positively effected.).  
         [0057]    The cover  45  includes a top wall  59 , a pair of side walls  60 , and a rear wall  61 . The side walls  60  are formed respectively at rear portions of opposite (right and left) side edges of the top wall  59 . The rear wall  61  is formed at a rear edge of the top wall  59 . The cover  45  is formed by these walls. A plurality of engagement portions  62  are formed at the side walls  47  of the case body  44  and the side walls  60  of the cover  45 , and the side walls  47  are engaged respectively with the side walls  60  by these engagement portions  62 .  
         [0058]    The second connector  25  includes a second core member  63  which is brought into close proximity to the first core member  26  when the door is closed, and a main case  27  provided at a front side of the second core member  63 , and a rectifier circuit device  64  provided at a rear side of the second core member  63 . The second connector  25  is fixedly secured to a generally hole-like connector mounting portion  65 , formed at an edge portion  24  of the door, by suitable fixing means (bolts in this embodiment). For the simplicity of description, those component parts, which are basically identical to those of the first connector  23  or common to the first and second connectors, will be designated respectively by the same reference numerals as used above.  
         [0059]    The second core member  63  includes a secondary core (secondary-side core)  66 , a secondary coil (secondary-side core)  67  received in the secondary core  66 , and a thermally-conductive filler  32  filled in a gap between the secondary core  66  and the secondary coil  67 . The secondary core  66  is formed, for example, by sintering ferrite powder, and this secondary core  66  has an annular groove  68  of a channel-shaped cross-section formed in one side thereof. The other side (face)  69  of the secondary core  66  is formed into a flat face for intimate contact with an aluminum case  42  (described later) of the secondary connector  25 . The secondary coil  67  is formed by winding a wire, and this secondary coil  67  is so formed as to be received in the annular groove  68 .  
         [0060]    The main case  27  of the secondary connector  25  has the coupling portion  36  which is fixedly secured to the second core member  63  by an adhesive or the like, and this coupling portion  36  serves to protect the second core member  63  and also to reduce an impact upon contact. When the door is closed, the coupling portion  36  of the first connector  23  is brought into close proximity to (or into contact with) the coupling portion  36  of the main case  27  of the second connector  25 .  
         [0061]    The rectifier circuit device  64  includes a circuit board  70  having a known rectifier circuit, and the aluminum case  42  which receives the circuit board  70 , and is connected directly to the second core member  63  to function as radiating means. The circuit board  70  is fixed to the aluminum case  42  of the second connector  25  by a plurality of projections  49 . The second core member  63  is fixedly secured to a core member-fixing wall  48  of the aluminum case  42  of the second connector  25 . A contact portion  53  of the aluminum case  42  of the second connector  25  is adapted to contact a peripheral edge portion of the connector mounting portion  65 .  
         [0062]    In the above construction, when the door is closed relative to the car body, the first connector  23  and the second connector  25  abut against each other, so that the coupling portions  36  of the first and second connectors  23  and  25  are brought into proximity to each other (or into contact with each other). When the primary coil  31  is excited, so that mutual induction is produced between the first core member  26  and the second core member  63 , the two are electromagnetically connected or coupled together, and electric power begins to be supplied from the car body to the door. Heat, produced by the mutual induction, transfers to the directly-connected aluminum cases  42 , and is discharged to the connector mounting portions  29  and  65  via the respective contact portions  53  of the aluminum cases  42 .  
         [0063]    As described above, the electromagnetic induction-type connector  21  of the invention has the heat radiation structure such that a large amount of electric power can be supplied, and the increase of the cost can be suppressed. And besides, the increase of the space and weight can be suppressed. Namely, in the electromagnetic induction-type connector  21  of the invention, heat, produced by the mutual induction, can be discharged to the connector mounting portions  29  and  65  via the directly-connected aluminum cases  42  (The increase of the temperature of the cores and coils can be suppressed during the supply of the electric power or during the transmission of the signal). And besides, any devices for fine temperature control (such as a protection circuit) do not need to be provided. In addition, an inexpensive material (for example, a material used for forming the main case  27 ) can be used. Furthermore, the cases for respectively receiving the circuit boards  41  and  70  contribute to the radiation of heat, and therefore the increase of the space and weight can be suppressed as compared with the case where radiating fins are additionally provided.  
         [0064]    Next, a modified example of the above electromagnetic induction-type connector  21  will be described with reference to FIGS.  9  to  11 . FIG. 9 is a cross-sectional view showing the modified example, FIG. 10 is a rear view of a first connector of FIG. 9, and FIG. 11 is a side-elevational view of the first connector of FIG. 9.  
         [0065]    In FIGS.  9  to  11 , the electromagnetic induction-type connector  21  includes waterproof and heat radiation sheets  71  each held between the connector and the corresponding connector mounting portion  29 ,  65 . Each of the waterproof and heat radiation sheets  71  is provided over the contact portion  53  of the corresponding aluminum case  42  and the flange  38  of the corresponding main case  27  (see a hatching portion in FIG. 10), and serves to prevent the intrusion of moisture while maintaining a heat-radiating ability (The waterproof effect is secured). For example, TC-TX (silicone rubber sheet, TC series, produced by Shin-Etsu Chemical Co., Ltd.) is used as the waterproof and heat radiation sheet  71 .  
         [0066]    One example of an electric power supply system for a vehicle, provided with the above electromagnetic induction-type connectors  21 , will be described with reference to FIG. 12. FIG. 12 is a block diagram of this example.  
         [0067]    In FIG. 12, a plurality of door bodies  82  are mounted on a car body  81  of the vehicle so as to be opened and closed relative to this car body  81 . The electromagnetic induction-type connector  21  for supplying electric power from the car body  81  to the corresponding door body  82  by mutual induction is provided at a door-connecting portion between the car body  81  and each of the door bodies  82 . The number of the electromagnetic induction-type connectors  21  corresponds to the number of the door bodies  82 , and each of these connectors  21  includes the first connector  23  mounted on the car body  81 , and the second connector  25  mounted on the corresponding door body  82 . Each first connector  23  is connected to a power supply line  83  provided at the car body  81 . Each second connector  25  is connected to a power supply line  84  provided at the corresponding door body  82 .  
         [0068]    The door bodies  82  are a driver&#39;s seat-side door  82   a , an assistant driver&#39;s seat-side door  82   a , a slide door  82   b , and a rear hatch  82   c , respectively.  
         [0069]    The construction of each of the above parts will be described. In addition to the first connectors  23  and the power supply line  83 , a generator  85 , a battery  86 , a control unit  87  and so on are mounted on the car body  81 . The generator  85  and the battery  86  are mounted within an engine room  88 , and the battery  86  is charged with electric power produced by the generator  85 . The power supply line  83  is connected to the battery  86 , and electric power is supplied from this battery to the control unit  87 . For example, a motor  89  is connected to the control unit  87 .  
         [0070]    The oscillation (driving) of each first connector  23  is controlled by the primary coil oscillation drive control device  28  (not shown. See FIG. 1). The primary coil oscillation drive control device  28  is connected to the power supply line  83 .  
         [0071]    In addition to the second connector  25  and the power supply line  84 , a battery  90 , a control unit  91  and so on are mounted on the door  82   a . The battery  90  is charged with an induction electromotive force, produced in the second connector  25 , via a rectifier circuit (not shown) and a charging circuit (not shown). The power supply line  84  is connected to the battery  90 . The control unit  91  is connected to the power supply line  84 , and is supplied with electric power from this power supply line. For example, a motor  92  is connected to the control unit  91 .  
         [0072]    In addition to the second connector  25  and the power supply line  84 , a battery  93 , a control unit  94  and so on are mounted on the slide door  82   b . The battery  93  is charged with an induction electromotive force, produced in the second connector  25 , via a rectifier circuit (not shown) and a charging circuit (not shown). The power supply line  84  is connected to the battery  93 . The control unit  94  is connected to the power supply line  84 , and is supplied with electric power from this power supply line. For example, a motor  95  is connected to the control unit  94 .  
         [0073]    In addition to the second connector  25  and the power supply line  64 , a battery  96 , a control unit  97  and so on are mounted on the rear hatch  82   c . The battery  96  is charged with an induction electromotive force, produced in the second connector  25 , via a rectifier circuit (not shown) and a charging circuit (not shown). The power supply line  84  is connected to the battery  96 . The control unit  97  is connected to the power supply line  84 , and is supplied with electric power from this power supply line. For example, a motor  98  is connected to the control unit  97 .  
         [0074]    In the above construction, each electromagnetic induction-type connector  21  operates in the following manner. First, when a key (not shown) is inserted into an ignition switch, and turns on this ignition switch, electric power is supplied to the primary coil oscillation drive control device  28  (not shown. See FIG. 1) connected to the power supply line  83 . When electric power is thus supplied to the primary coil oscillation drive control device  28 , the primary coil  31  (not shown. See FIG. 1) of each first connector  23  is driven or oscillated by the primary coil oscillation drive control device  28 , so that an AC electromotive force is produced in the primary coil  31 .  
         [0075]    When the door  82   a  is closed relative to the car body  81 , an induction electromotive force is produced in the second connector  25  through mutual induction between the second connector and the first connector  23 . The battery  90  is charged with the thus produced induction electromotive force via the rectifier circuit (not shown) and the charging circuit (not shown). When the door  82   a  is open relative to car body  81 , electric power is supplied from the battery  90  to the power supply line  84 . Heat, produced by the mutual induction, is discharged (radiated) to the car body  81  and the door  82   a.    
         [0076]    When the slide door  82   b  is closed relative to the car body  81 , an induction electromotive force is produced in the second connector  25  through mutual induction between the second connector and the first connector  23 . The battery  93  is charged with the thus produced induction electromotive force via the rectifier circuit (not shown) and the charging circuit (not shown). When the slide door  82   b  is open relative to car body  81 , electric power is supplied from the battery  93  to the power supply line  84 . Heat, produced by the mutual induction, is discharged (radiated) to the car body  81  and the slide door  82   b.    
         [0077]    When the rear hatch  82   c  is closed relative to the car body  81 , an induction electromotive force is produced in the second connector  25  through mutual induction between the second connector and the first connector  23 . The battery  96  is charged with the thus produced induction electromotive force via the rectifier circuit (not shown) and the charging circuit (not shown). When the rear hatch  82   c  is open relative to car body  81 , electric power is supplied from the battery  96  to the power supply line  84 . Heat, produced by the mutual induction, is discharged (radiated) to the car body  81  and the door  82   c.    
         [0078]    Various modifications can be made within the scope of the invention. Namely, this invention is explained by using the car body and the door body (the door, the slide door and the rear hatch), respectively, however these are not limited to the present invention. Such examples include a steering of a door (separate side: a steering portion), and a seat of a vehicle (separate side: a seat portion). The invention can be applied to any suitable two members, related to a vehicle, in so far as the supply of electric power (or the transmission of a signal) need to be effected between the two members by mutual induction. In the above embodiments, although the heat radiation structure is provided in each of the first core member  26  and the second core member  63 , the heat radiation structure is not limited to this arrangement.