Patent Publication Number: US-2022219623-A1

Title: Vehicle exterior part

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2021-003670 filed on Jan. 13, 2021. 
     TECHNICAL FIELD 
     The present specification relates to a vehicle exterior part for decorating a vehicle, such as an emblem, an ornament, or a mark. 
     BACKGROUND ART 
     In a vehicle which incorporates a millimeter wave radar device, a millimeter wave is transmitted from the device toward the outside of the vehicle. When the millimeter wave is reflected by an object outside the vehicle, such as a preceding vehicle or a pedestrian, the reflected millimeter wave is received by the millimeter wave radar device. Transmission and reception of the millimeter wave enable recognition of the object and detection of a distance, a relative speed, and the like between the vehicle and the object. 
     The vehicle has a vehicle exterior part such as an emblem disposed in front of the millimeter wave radar device in a transmission direction of the millimeter wave. The vehicle exterior part is provided with a decorative body which hides the millimeter wave radar device and has permeability of millimeter wave. The decorative body includes a base material and a transparent resin layer disposed on an exterior side from the base material. 
     Such vehicle exterior part has a problem that when ice and snow adhere to a design surface (exterior surface) thereof, the millimeter wave is attenuated, which decreases detection performance of the millimeter wave radar device. Therefore, it has been considered to add a snow melting function to the vehicle exterior part. The snow melting function is added by, for example, providing a heater sheet and a connector pin to the decorative body. 
     The heater sheet is formed by wiring a heater wire, which generates heat when energized, on an interior surface of a sheet base material. The heater sheet includes a heat generating body disposed on an exterior side from the transparent resin layer, and an extending portion extending from a peripheral edge of the heat generating body and disposed on an interior side of the transparent resin layer. 
     The connector pin is a portion to be coupled with a device for power supply. A part of the heater wire in the extending portion is joined to the connector pin inside the outer periphery of the base material by a joining portion made of a conductive material, so that the connector pin and the heater wire are electrically connected. 
     According to the vehicle exterior part, the electric power supplied from the device is supplied to the heater wire via the connector pin, so that the heater wire generates heat. Therefore, even if ice and snow adhere to the design surface (exterior surface) of the vehicle exterior part, it is possible to melt the ice and snow by the heat generated by the heater wire, thereby preventing the millimeter wave from being attenuated due to the adhesion of the ice and snow. 
     For example, JP-A-2020-5057 describes a technique of laminating a heater sheet on an exterior side of the decorative body. 
     The vehicle exterior part has a window for joining the heater wire to the connector pin by the joining portion. The window is formed in the outer periphery of the base material in a state where a joining position is exposed to the outside of the outer periphery. The window is provided with a waterstop portion for restricting water from entering the joining position. 
     However, if the ambient temperature changes repeatedly after the vehicle exterior part is assembled to the vehicle, the following problem may occur depending on the structure of the waterstop portion. This problem may occur, for example, if the waterstop portion is formed by filling the window with a hard resin material and the waterstop portion is in contact with the joining portion and the heater wire. That is, when the temperature changes repeatedly, the waterstop portion tends to expand and contract more than the heater wire, and stress is concentratedly applied to a boundary between the joining portion and the heater wire. As a result, the joining of the heater wire to the connector pin by the joining portion may be released, which causes disconnection. 
     Such a problem is not limited to the millimeter wave radar device, and may similarly occur as long as it is a vehicle exterior part incorporated in a vehicle equipped with a device for transmitting and receiving electromagnetic wave for detecting an object outside the vehicle, and provided with a heater sheet on the exterior side of the decorative body. The same phenomenon as described above may also occur in a vehicle exterior part incorporated in a vehicle without being equipped with a device for transmitting and receiving electromagnetic wave, and provided with a heater sheet on the exterior side of the decorative body. 
     SUMMARY OF INVENTION 
     According to an aspect of the present specification, a vehicle exterior part includes; a decorative body configured to decorate a vehicle; a heater sheet including a heater wire configured to generate heat when energized, the heater wire being wired on an interior surface of a sheet base material; and a connector pin configured to be coupled with a device for power supply. The decorative body includes a base material and a transparent resin layer disposed on an exterior side from the base material. The heater sheet includes a heat generating body disposed on an exterior side from the transparent resin layer, and an extending portion extending from a peripheral edge of the heat generating body and disposed on an interior side from the transparent resin layer. A part of the heater wire in the extending portion is joined to the connector pin inside the outer periphery of the base material by a joining portion made of a conductive material. The outer periphery is formed with a window configured to join the heater wire to the connector pin by the joining portion. The window is formed in a state where a joining position is exposed to an outside of the outer periphery. The window is provided with a waterstop portion configured to restrict water from entering the joining position. The waterstop portion is formed by filling the window with a potting material. 
     According to the above configuration, the waterstop portion which blocks the window is formed by filling the window with a potting material. The potting material is in close contact with a wall surface of the window. Therefore, the waterstop portion can restrict water from the outside of the window from entering the joining position of the heater wire to the connector pin. 
     Here, when the vehicle exterior part is assembled to the vehicle and is placed in an environment in which the temperature changes repeatedly, the waterstop portion and the heater wire expand and contract according to the temperature change. 
     In this regard, the above configuration uses the potting material to form the waterstop portion. The potting material is made of a soft resin material. Therefore, stress is less likely to be concentrated on the boundary between the joining portion and the heater wire regardless of a difference in linear expansion coefficient between the heater wire and the waterstop portion. Therefore, the joining state of the heater wire to the connector pin is maintained favorably, which can prevent disconnection. 
     According to an aspect of the present specification, a vehicle exterior part includes; a decorative body configured to decorate a vehicle; a heater sheet including a heater wire configured to generate heat when energized, the heater wire being wired on an interior surface of a sheet base material; and a connector pin configured to be coupled with a device for power supply. The decorative body includes a base material and a transparent resin layer disposed on an exterior side from the base material. The heater sheet includes a heat generating body disposed on an exterior side from the transparent resin layer and an extending portion extending from a peripheral edge of the heat generating body and disposed on an interior side from the transparent resin layer. A part of the heater wire in the extending portion is joined to the connector pin inside the outer periphery of the base material by a joining portion made of a conductive material. The outer periphery is formed with a window configured to join the heater wire to the connector pin by the joining portion. The window is formed in a state where a joining position is exposed to an outside of the outer periphery. The window is provided with a waterstop portion configured to restrict water from entering the joining position. The waterstop portion includes a cover formed of a resin material. The cover is arranged with a gap from the joining position, and blocks the window in close contact with a peripheral edge of the window, the window being on an exterior side from the gap. 
     According to the above configuration, the waterstop portion which blocks the window includes the cover formed of a resin material. The waterstop portion blocks the window in close contact with the peripheral edge of the window. Therefore, the waterstop portion can restrict water from the outside of the window from entering the joining position of the heater wire to the connector pin. 
     Here, when the vehicle exterior part is assembled to the vehicle and is placed in an environment in which the temperature changes repeatedly, the waterstop portion and the heater wire expand and contract according to the temperature change. 
     In this regard, according to the above configuration, the waterstop portion includes the resin cover. The cover is arranged with a gap from the joining position by the joining portion of the heater wire to the connector pin. The cover is not in direct contact with the joining portion and the connector pin. Therefore, stress is less likely to be concentrated on the boundary between the joining portion and the heater wire regardless of a difference in linear expansion coefficient between the heater wire and the waterstop portion. Therefore, the joining state of the heater wire to the connector pin is maintained favorably, which can prevent disconnection. 
     The waterstop portion including the cover is separated from the joining position. Therefore, the joining position is not pressed by the waterstop portion, which prevents a risk that the joining of the heater wire to the connector pin is disconnected due to pressing. 
     In the vehicle exterior part, it is preferable that the waterstop portion is welded to the peripheral edge of the window. 
     According to such configuration, the waterstop portion is welded to the peripheral edge of the window, so that the waterstop portion and the peripheral edge of the window are joined to each other in a molten state. Therefore, the welded portion can restrict intrusion of water from the outside to the inside of the window. 
     The vehicle exterior part can favorably maintain the joining state of the heater wire to the connector pin even when the ambient temperature changes repeatedly. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  illustrates a front view of a first embodiment, which is a vehicle exterior part embodied as an emblem. 
         FIG. 2  is a partial rear view illustrating a part of a heater sheet together with a decorative body according to the first embodiment. 
         FIG. 3  is a partial side cross-sectional view illustrating a lower structure of the emblem together with a part of a front grille and a part of a millimeter wave radar device according to the first embodiment. 
         FIG. 4  is a cross-sectional view of a socket section taken along line  4 - 4  of  FIG. 3 . 
         FIG. 5  is a partial cross-sectional view illustrating a joining position of a heater wire by a joining portion together with a periphery thereof according to the first embodiment. 
         FIG. 6  illustrates an emblem according to a second embodiment, and is a cross-sectional view of a socket portion corresponding to  FIG. 4 . 
         FIG. 7  is a partial cross-sectional view illustrating a joining position of a heater wire by a joining portion together with a periphery thereof according to the second embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     First Embodiment 
     Hereinafter, a first embodiment in which a vehicle exterior part is embodied as an emblem to be attached to a front portion of a vehicle will be described with reference to  FIGS. 1 to 5 . 
     In the following description, a forward direction of the vehicle is referred to as front, and a backward direction is referred to as rear. An upper-lower direction refers to an upper-lower direction of the vehicle. A left-right direction refers to a vehicle width direction and coincides with a left-right direction when the vehicle moves forward. The drawings are illustrated with a scale of the parts of the emblem changed appropriately so that the parts can be recognized. 
     As illustrated in  FIG. 3 , a millimeter wave radar device  13  for forward monitoring is disposed at a central portion in the vehicle width direction of a front portion of a vehicle  10  and behind a front grille  11 . The millimeter wave radar device  13  has a function of transmitting a millimeter wave among electromagnetic waves to the front of the outside of the vehicle and receiving a millimeter wave reflected by an object outside the vehicle. The millimeter wave refers to a radio wave having a wavelength of 1 mm to 10 mm and a frequency of 30 GHz to 300 GHz. 
     The front grille  11  has a non-constant thickness as in the case of a general front grille. The front grille  11  may include a metal plating layer formed on an exterior surface of a resin base material. Therefore, the front grille  11  interferes with the transmitted or reflected millimeter wave. Therefore, the front grille  11  has a window  12  opened in front of the millimeter wave radar device  13  in a transmission direction of the millimeter wave.  FIG. 3  illustrates a lower portion of the window  12 . 
     The window  12  is provided with an emblem  15 . The emblem  15  has a surface on the vehicle front side (right side in  FIG. 3 ) which constitutes a design surface  15   a . The design surface  15   a  has an elliptical outer shape which is horizontally long. Here, when describing the emblem  15 , a side facing the design surface  15   a  is referred to as an exterior side, and a side opposite to the design surface  15   a  (the left side in  FIG. 3 ) is referred to as an interior side. 
     The emblem  15  is disposed in an upright state. In this state, the exterior side of the emblem  15  corresponds to the front side of the vehicle  10 , and the interior side of the emblem corresponds to the rear side of the vehicle  10 . 
     Therefore, when describing the emblem  15  alone, the terms “exterior” and “interior” are used for specifying directions corresponding to the front and rear directions of the vehicle. The same applies to a case of describing the emblem  15  when the emblem  15  is attached to the vehicle  10 . 
     The emblem  15  includes a decorative body  21  and a heater sheet  51 . Next, members constituting the emblem  15  will be described. 
     &lt;Decorative Body  21 &gt; 
     As illustrated in  FIGS. 1 and 3 , the decorative body  21  is a portion for decorating the vehicle  10  and is disposed on the front side of the vehicle  10  in the direction for transmitting the millimeter wave from the millimeter wave radar device  13 . A main portion of the decorative body  21  has a substantially elliptical plate shape which is horizontally long, which corresponds to the design surface  15   a  of the emblem  15 , and has millimeter wave transparency. 
     The decorative body  21  includes a base material  22 , a transparent resin layer  35 , and a decorative layer  41 . The base material  22  is a member constituting an interior portion of the decorative body  21 . The base material  22  includes a base material body  23  constituting a skeleton portion of the base material  22 , and a frame  31  provided on an outer periphery of the base material body  23 . 
     The base material body  23  is formed of acrylonitrile-ethylene-styrene copolymer (AES) resin in a colored manner. An exterior portion of the base material body  23  is formed with a substantially flat general portion  24  intersecting an exterior-interior direction in a state close to being orthogonal thereto, and a protrusion  25  protruding more exterior than the general portion  24 . The general portion  24  corresponds to a background region  16  of the emblem  15  in  FIG. 1 , and the protrusion  25  corresponds to a pattern region  17  of the emblem  15 . Here, the pattern region  17  includes a character portion  18  of “A” and an annular portion  19  around the character portion  18 . 
     As illustrated in  FIG. 3 , an outer periphery of the base material body  23  is formed with an annular recess  26  which is opened in the exterior surface thereof and recessed toward the interior side. The annular recess  26  has a substantially elliptical annular shape corresponding to the peripheral edge of the base material body  23 . 
     The base material  22  has, in a lower portion thereof, a socket portion  27  protruding toward the interior side. The socket portion  27  is a portion for inserting and removing a plug portion B of the device A for power supply. An exterior portion of the socket portion  27  is formed with a recess  28  extending toward the interior side from the annular recess  26 . Further, the socket portion  27  is formed with a recess  29  which is opened in an interior surface thereof and recessed toward the exterior side. 
     Instead of AES resin, the base material body  23  may be formed of acrylonitrile-styrene-acrylate copolymer (ASA) resin, polycarbonate (PC) resin, a polymer alloy of PC resin and acrylonitrile-butadiene-styrene copolymer (ABS) resin, or the like. 
     The frame  31  is provided along the outer periphery of the base material body  23  to form a substantially elliptical annular shape (see  FIG. 1 ). A majority part of the frame  31  is filled in the annular recess  26 . A part of a lower portion of the frame  31  is filled in the recess  28  of the socket portion  27 . The frame  31  is formed of, for example, a mixed material of PC resin and carbon black, and has a black color. 
     As illustrated in  FIGS. 3 and 4 , the socket portion  27  is provided with two connector pins  32  extending in the exterior-interior direction in a state of being separated from each other in the left-right direction. Each connector pin  32  has an exterior portion  32   a  formed in a flat plate shape and embedded in the base material body  23  and the frame  31 . Further, each connector pin  32  has an interior portion  32   b  having a rod shape. The portion  32   b  is partially arranged in the recess  29 . 
     A part of the outer periphery  22   a  of the base material  22  which is below the socket portion  27  is formed with a window  30  which is opened in a lower surface of the socket portion  27 . The window  30  is provided for joining heater wires  56 ,  57 , which will be described later, to the connector pin  32 . 
     A peripheral edge of the interior surface of the base material  22  (base material body  23 ) is provided with attachment portions (not illustrated) for attaching the emblem  15  to the front grille  11  or the vehicle body at plural positions. Each attachment portion is configured with a clip, a screw, an engagement claw, or the like. 
     As illustrated in  FIGS. 1 and 3 , the transparent resin layer  35  is a member constituting an exterior portion of a main portion of the decorative body  21 . The transparent resin layer  35  is formed of PC resin so as to be transparent. The term “transparent” as used herein includes not only colorless and transparent, but also colored and transparent. The same applies to a sheet base material  55  to be described later. An interior portion of the transparent resin layer  35  is formed in a shape corresponding to the shape of the exterior portion of the base material body  23 . That is, a portion on the interior side of the transparent resin layer  35  that is on the exterior side of the general portion  24  of the base material body  23  is formed with a substantially flat general portion  36  intersecting the exterior-interior direction in a state close to being orthogonal thereto. A portion on the interior side of the transparent resin layer  35  that is on the exterior side of the protrusion  25  of the base material body  23  is formed with a recess  37  recessed more exterior than the general portion  36 . An outer periphery of the transparent resin layer  35  is located on the exterior side of the frame  31 . The transparent resin layer  35  may be formed of a transparent resin such as polymethyl methacrylate (PMMA) resin instead of the PC resin. 
     The decorative layer  41  is formed in a region surrounded by the frame  31  between the base material body  23  and the transparent resin layer  35 , and has millimeter wave transparency. The decorative layer  41  is constituted by, for example, a combination of a colored decorative layer having a dark color such as black or blue and a bright decorative layer made of a metal material such as indium (In). 
     In the decorative body  21 , the frame  31  is welded to the base material body  23  and the transparent resin layer  35 , so as to couple the base material body  23  and the transparent resin layer  35  to each other. 
     In the decorative body  21 , a region for transmitting millimeter wave has a constant thickness. 
     &lt;Heater Sheet  51 &gt; 
     As illustrated in  FIGS. 2 and 3 , the heater sheet  51  includes a sheet base material  55  and two heater wires  56 ,  57 . The sheet base material  55  is formed of a transparent resin material such as PC resin. Each of the heater wires  56 ,  57  is made of a metal material which generates heat when energized, and is wired on the interior surface of the sheet base material  55 . 
     The heater sheet  51  includes a heat generating body  52 , and an extending portion  53  extending from a peripheral edge of the heat generating body  52 , that is, a lower edge in the first embodiment. A direction in which the extending portion  53  extends from the heat generating body  52  is referred to as an extending direction of the extending portion  53 . A direction orthogonal to the extending direction along a surface of the extending portion  53  is referred to as a width direction of the extending portion  53 . The heat generating body  52  is formed in a horizontally long elliptical shape corresponding to the design surface  15   a  of the emblem  15 . The heat generating body  52  is laminated on the exterior side of the transparent resin layer  35 . In the heat generating body  52 , the heater wires  56 ,  57  are wired in different wiring patterns (see  FIG. 2 ). 
     The extending portion  53  is bent along a lower surface of the transparent resin layer  35 , a lower surface of the frame  31 , and the like, so as to go around the transparent resin layer  35  on the interior side via a lower end portion of an outer periphery of the decorative body  21 . 
     As illustrated in  FIGS. 3 and 4 , each side portion of the extending portion  53  in the width direction is formed with an opening  54 . The openings  54  are spaced apart from each other in the width direction. 
     As illustrated in  FIGS. 2 to 4 , the two heater wires  56 ,  57  are wired not only in the heat generating body  52 , but also in the extending portion  53 . That is, the heater wire  56  has terminals  56   a ,  56   b  at both end portions thereof. The heater wire  57  has terminals  57   a ,  57   b  at both end portions. The terminals  56   a ,  57   a  are collectively wired on one side portion in the width direction on the interior surface of the extending portion  53 . The terminals  56   a ,  57   a  each partially intersect with one opening portion  54  in the extending direction. Similarly, the terminals  56   b ,  57   b  are collectively wired on the other side portion in the width direction on the interior surface of the extending portion  53 . The terminals  56   b ,  57   b  each partially intersect with the other opening portion  54  in the extending direction. 
     As illustrated in  FIGS. 3 and 4 , the part of the extending portion  53  which goes around to the interior side via the lower end portion of the outer periphery of the decorative body  21  is arranged between an outer peripheral surface of the frame  31  and an inner wall surface of the recess  28 . 
     The exterior portion  32   a  of each connector pin  32  partially overlaps a part of the extending portion  53  that is a periphery of the opening  54  from the exterior side (outer peripheral side). The terminals  56   a ,  57   a  are soldered in the one opening  54 , so as to be joined to the exterior portion  32   a . Similarly, the terminals  56   b ,  57   b  are soldered in the other opening  54 , so as to be joined to the exterior portion  32   a . In  FIGS. 3 and 4 , reference numeral  58  denotes a joining portion made of a solder alloy and formed by soldering. These joining portions  58  electrically connect the terminals  56   a ,  56   b  and the terminals  57   a ,  57   b  to the exterior portions  32   a  of the connector pins  32  inside the outer periphery  22   a  of the base material  22 . 
     The joining may be performed by adhesion using a conductive adhesive, welding, or the like, instead of soldering. 
     Portions where the terminals  56   a ,  56   b  and the terminals  57   a ,  57   b  are joined to the connector pins  32  by the joining portions  58  are referred to as joining positions. The window  30  is provided with a waterstop portion  71  for restricting water from entering the joining positions. In the first embodiment, the waterstop portion  71  is formed by filling the window  30  with a resin material softer than the base material  22 . The resin material is a potting material. Here, the potting material is generally a filling material for filling an entire electric circuit for the purpose of protecting the electric circuit or the like from impact, vibration, moisture, or corrosion, and is rubber-like, gel-like, etc. The potting material may be, for example, an epoxy resin, an acrylic resin, a urethane resin, a silicone resin, or the like. The waterstop portion  71  is in direct contact with the joining positions. 
     As illustrated in  FIG. 3 , the emblem  15  configured as described above is disposed inside the window  12  in an upright state, and is attached to the front grille  11  or the vehicle body at the attachment portion. 
     The plug portion B of the device A is inserted into the recess  29  of the socket portion  27  from the interior side of the emblem  15 , so that the heater wires  56 ,  57  are electrically connected to the device A. 
     Next, an operation of the first embodiment configured as described above will be described. An effect produced by the operation will be described together. 
     As illustrated in  FIGS. 3 to 5 , in the emblem  15  of the first embodiment, the window  30  is formed in the outer periphery  22   a  of the base material  22 , and water may enter the joining positions between the terminals  56   a ,  56   b , the terminals  57   a ,  57   b  and the connector pins  32  from the window  30 . However, the window  30  is blocked by the waterstop portion  71 . The waterstop portion  71  is formed by filling the window  30  with a potting material made of a soft resin material. The potting material is in close contact with a wall surface of the window  30 . The waterstop portion  71  and the wall surface have no or almost no gap therebetween. Therefore, the waterstop portion  71  can restrict the water from entering the joining positions from the outside of the window  30 . 
     Here, when the emblem  15  assembled to the vehicle  10  is placed in an environment in which the ambient temperature changes repeatedly, the waterstop portion  71 , the terminals  56   a ,  56   b , and the terminals  57   a ,  57   b  expand and contract according to the temperature change. If the waterstop portion  71  is formed of a hard resin material such as AES resin and PC resin similarly to the base material  22 , the following phenomenon occurs when the waterstop portion  71  expands and contracts more than the terminals  56   a ,  56   b  and the terminals  57   a ,  57   b  due to a difference in linear expansion coefficient between the heater wires  56 ,  57  and the waterstop portion  71 . That is, stress is concentratedly applied to a boundary C between the joining portions  58  and the terminals  56   a ,  56   b , the terminals  57   a ,  57   b . As a result, the joining of the terminals  56   a ,  56   b  and the terminals  57   a ,  57   b  to the connector pins  32  by the joining portions  58  may be released, which causes disconnection. 
     In this regard, in the first embodiment, the potting material, which is a resin material softer than the base material body  23  and the frame  31 , is used as the material of the waterstop portion  71 . The potting material is filled in the window  30  to form the waterstop portion  71 . Therefore, stress is less likely to be concentrated on the boundary C regardless of the difference in linear expansion coefficient between the heater wires  56 ,  57  and the waterstop portion  71 . Therefore, the connection state of the terminals  56   a ,  56   b  and the terminals  57   a ,  57   b  to the connector pins  32  can be maintained favorably, thereby preventing disconnection. 
     When ice and snow adhere to the design surface  15   a  of the emblem  15 , as illustrated in  FIG. 3 , electric power is supplied to the heater wires  56 ,  57  via the plug portion B of the device A and the connector pins  32 . The heater wires  56 ,  57  generate heat when energized. The heat generated by the heater wires  56 ,  57  is partially transmitted to the design surface  15   a  of the emblem  15 . This heat melts the ice and snow adhering to the design surface  15   a , and prevents attenuation of millimeter wave due to the ice and snow. 
     In particular, in the first embodiment, the heater sheet  51  is disposed at a most exterior position in the emblem  15 . Therefore, the heat generated by the heater wires  56 ,  57  is easily transmitted to the design surface  15   a  (exterior surface) of the emblem  15 , and the ice and snow can be melted efficiently. 
     When millimeter wave is transmitted from the millimeter wave radar device  13 , the millimeter wave sequentially passes through the base material body  23 , the decorative layer  41 , and the transparent resin layer  35  in the decorative body  21  of the emblem  15 , and the heat generating body  52  of the heater sheet  51 . The transmitted millimeter wave is reflected by an object in front of the vehicle including a preceding vehicle, a pedestrian, and the like, and then sequentially passes through the heat generating body  52  of the heater sheet  51 , and the transparent resin layer  35 , the decorative layer  41 , and the base material body  23  in the decorative body  21 . The millimeter wave transmitted through the decorative body  21  is received by the millimeter wave radar device  13 . The millimeter wave radar device  13  recognizes the object and detects a distance, a relative speed, and the like between the vehicle  10  and the object based on the transmitted and received millimeter wave. 
     When the emblem  15  is irradiated with visible light from the front side of the vehicle  10 , the visible light passes through the heat generating body  52  of the heater sheet  51  and the transparent resin layer  35  of the decorative body  21 , and is reflected by the decorative layer  41 . When the emblem  15  is viewed from the front side of the vehicle  10 , the decorative layer  41  can be seen through the heat generating body  52  and the transparent resin layer  35  and appears to be positioned on the interior side thereof. In this way, the decorative layer  41  decorates the emblem  15 , and improves the appearance of the emblem  15  and the periphery thereof. 
     The reflection of the visible light by the decorative layer  41  is performed in front of the millimeter wave radar device  13 . The decorative layer  41  has a function of covering the millimeter wave radar device  13 . Therefore, the millimeter wave radar device  13  can hardly be seen from the front side of the emblem  15 . Therefore, the appearance of the millimeter wave radar device  13  is improved as compared with a case where the millimeter wave radar device  13  can be seen through the emblem  15 . 
     According to the first embodiment, the following effects are obtained in addition to the above effects. 
     In the first embodiment, as illustrated in  FIGS. 3 and 4 , the one connector pin  32  and the terminals  56   a ,  57   a  are joined to each other inside the outer periphery  22   a  of the base material  22 . The other connector pin  32  and the terminals  56   b ,  57   b  are also joined to each other inside the outer periphery  22   a . The joining portions are covered with the outer periphery  22   a . Therefore, unlike the case where the joining is performed on the exterior side of the transparent resin layer  35 , the appearance is not deteriorated by the joining portions. 
     Second Embodiment 
     Next, a second embodiment in which a vehicle exterior part is embodied as an emblem will be described with reference to  FIGS. 6 and 7 . 
     The second embodiment is different from the first embodiment in the configuration of the waterstop portion  71 . The waterstop portion  71  includes a cover made of a hard resin material. In the second embodiment, the waterstop portion  71  is formed of AES resin similarly to the base material body  23 . 
     The waterstop portion  71  is arranged with a gap G 1  from the joining positions of the terminals  56   a ,  56   b  and the terminals  57   a ,  57   b  to the connector pins  32  by the joining portions  58 . The waterstop portion  71  is welded to positions surrounding the joining positions in a peripheral edge  72  of the window  30  which is located on the exterior side (outer peripheral side) of the joining positions. The welding is performed by, for example, a welding method such as ultrasonic welding, laser welding, and hot plate welding. 
     The configuration other than the above is the same as that of the first embodiment. Therefore, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description thereof will be omitted. 
     Therefore, the same operation and effect as those of the first embodiment can also be obtained by the second embodiment. That is, in the emblem  15  of the second embodiment, the window  30  is blocked by the waterstop portion  71  formed using a hard resin material. The waterstop portion  71  is welded to the peripheral edge  72  of the window  30 , so that the waterstop portion  71  and the peripheral edge  72  are joined to each other in a molten state. The waterstop portion  71  blocks the window  30  in close contact with the peripheral edge  72 . Therefore, the waterstop portion  71  can restrict water from entering the joining positions from the outside of the window  30 . 
     In the second embodiment, the waterstop portion  71  includes a resin cover, and the waterstop portion  71  is arranged with the gap G 1  from the joining positions. Unlike the first embodiment, the waterstop portion  71  is not in direct contact with the joining positions. Therefore, stress is less likely to be concentrated on the boundary C between the joining portions  58  and the terminals  56   a ,  56   b , the terminals  57   a ,  57   b  regardless of the difference in linear expansion coefficient between the heater wires  56 ,  57  and the waterstop portion  71 . Therefore, the connection state of the terminals  56   a ,  56   b  and the terminals  57   a ,  57   b  to the connector pins  32  can be maintained favorably, thereby preventing disconnection. 
     The waterstop portion  71  is separated from the joining positions. Therefore, the joining positions are not pressed by the waterstop portion  71 . The joining of the terminals  56   a ,  56   b  and the terminals  57   a ,  57   b  to the connector pins  32  by the joining portions  58  can be prevented from being released due to the pressing, thereby preventing disconnection. 
     The above embodiment may be modified into the modifications as follows. The above embodiment and the following modifications can be combined with each other to the extent that they are not technically contradictory to each other. 
     The number of the heater wires  56 ,  57  in the heater sheet  51  may be changed to one or three or more. 
     The extending portion  53  may extend from a position of the peripheral edge of the heat generating body  52  other than the lower edge thereof, for example, an upper edge, a side edge, or the like. 
     The outer shape of the design surface  15   a  of the emblem  15  may be changed to a shape other than the horizontally long elliptical shape. 
     The heater wires  56 ,  57  in the heat generating body  52  of the heater sheet  51  may be wired in a wiring pattern different from those in the first and second embodiments. 
     The vehicle exterior part can be applied as long as the vehicle exterior part is incorporated in a vehicle equipped with a device for transmitting and receiving electromagnetic wave for detecting an object outside the vehicle, and provided with a heater sheet on an exterior side of a decorative body. In this case, the electromagnetic wave transmitted and received by the device includes millimeter wave, infrared ray, and the like. 
     The device for transmitting and receiving electromagnetic wave for detecting an object outside the vehicle may be a device for rear monitoring, a device for front lateral side monitoring, or a device for rear lateral side monitoring, in addition to the device for front monitoring. In this case, the vehicle exterior part is disposed in front of the device in the transmission direction of the electromagnetic wave. 
     The vehicle exterior part may be incorporated in a vehicle without being equipped with a device for transmitting and receiving electromagnetic wave for detecting an object outside the vehicle. 
     The vehicle exterior part may be applied to a vehicle exterior part having a function of decorating a vehicle such as an ornament or a mark, in addition to the emblem.