Patent Publication Number: US-8534104-B2

Title: Portable wireless key

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is based on and claims priority to Japanese Patent Application No. 2010-173445 filed on Aug. 2, 2010, the contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to potable wireless keys for locking/unlocking a door of a vehicle by wirelessly communicating with the vehicle, in particular, a portable wireless key having a wireless key body in which an emergency key as a mechanical key for locking/unlocking the door is inserted and held. 
     BACKGROUND 
     In recent years, there has been an increase in the number of vehicles equipped with an electronic key system such as a keyless entry system, a smart entry system, or a smart start system. As described in, for example, JP-A-2001-40921, such an electronic key system includes a portable wireless key for performing wireless communication with a vehicle. In case that a battery of the key is exhausted and that a battery of the vehicle is exhausted, the portable wireless key is generally provided with an emergency key. 
     In the emergency key, an end portion of a key plate portion has a grip portion, and the grip portion has a ring portion. Generally, the emergency key is held in a body of the portable wireless key in such a manner that the ring portion can be used. 
     When the portable wireless key is left in a hotel (so that a staff of the hotel can drive the vehicle to a parking lot), the emergency key is generally removed from the body before the portable wireless key is left. As a result, the body of the portable wireless key does not have the ring portion. Therefore, the hotel cannot use the ring portion to store and keep the portable wireless key. 
     Generally, a key ring is attached to the ring portion of the emergency key to keep the emergency key and other keys together. In such a case, the ring portion may be unavailable, even when the ring portion is wanted to be used at home or the like to hang the emergency key on a hook, for example. 
     It may be considered that a catch portion such as a projection is formed to the body. However, the projection may be caught when the portable wireless key is carried in a pocket. Further, the projection may spoil the design of the portable wireless key. 
     SUMMARY 
     In view of the above, it is an object of the present invention to provide a convenient-to-use portable wireless key having a hook that can be used to keep the portable wireless key. The hook is formed at a portion other than an emergency key without spoiling a design of the portable wireless key. 
     According to an aspect of the present invention, a portable wireless key for locking/unlocking a door of a vehicle by wirelessly communicating with the vehicle includes a body. An emergency key as a mechanical key for locking/unlocking the door is inserted and held in the body. The body has an operation surface and a protrusion action portion. The operation surface defines a part of an outer side surface of the body. The protrusion action portion has a hook that is held in the body under a condition that the emergency key is held in the body. One push to the operation surface causes the protrusion action portion to perform a protrusion action. The protrusion action causes the protrusion action portion to protrude outward from the body in such a manner that the hook of the protrusion action portion is exposed outside the body. 
     Since the protrusion action portion having the hook is held inside the key body, the hook can be exposed outside and used whenever the hook becomes necessary. Further, since the hook can be held inside whenever the hook becomes unnecessary, a design of the portable wireless key is not spoiled. Furthermore, since the hook can be exposed outside by one push, a user can easily expose the hook outside. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features, and advantages will become more apparent from the following description and drawings in which like reference numerals depict like elements. In the drawings: 
         FIG. 1  is a diagram illustrating an outside view of a portable wireless key according to a first embodiment of the present invention; 
         FIGS. 2A and 2B  are diagrams for explaining a protrusion action of the portable wireless key of  FIG. 1 ; 
         FIGS. 3A and 3B  are diagrams illustrating exploded views of  FIGS. 2A and 2B , respectively; 
         FIGS. 4A and 4B  are diagrams for explaining a protrusion action of a portable wireless key according to a second embodiment of the present invention; and 
         FIGS. 5A and 5B  are diagrams illustrating exploded views of  FIGS. 4A and 4B , respectively. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     First Embodiment 
     A portable wireless key  1  according a first embodiment of the present invention is used for an electronic key system such as a keyless entry system, a smart entry system, or a smart start system of a vehicle, for example. The portable wireless key  1  wirelessly communicates with the vehicle to lock/unlock a door of the vehicle. In the electronic key system, the vehicle wirelessly outputs a polling radio wave in a predetermined key search area, and the portable wireless key  1  is searched in the search area based on wireless reception of a response signal. Then, the vehicle is controlled in a predetermined manner based on an ID code that is wirelessly received from the portable wireless key  1 . 
     According to the first embodiment, the portable wireless key  1  is configured as a so-called smart key for the smart entry system and the smart start system of the vehicle. In the smart entry system, when the portable wireless key  1  is located in a predetermined key search area outside the vehicle, an ID code is wirelessly returned from the portable wireless key  1  and checked. Then, a permission to unlock the door is given based on the check result. Then, when a predetermined unlock operation is detected under a condition that the permission to unlock the door is given, a door lock mechanism is activated to unlock the door. That is, a switching between a unlock permission condition and a unlock prohibition condition is performed based on the check result. In the unlock permission condition, the door can be unlocked by the predetermined unlock operation. In the unlock prohibition condition, the door cannot be unlocked. 
     In the smart start system, when the portable wireless key  1  is located in a predetermined key search area inside the vehicle, an ID code is wirelessly returned from the portable wireless key  1  and checked. Then, a permission to start an engine is given based on the check result. Then, when a predetermined engine start operation is detected under a condition that the permission to start the engine is given, the engine is started. That is, a switching between a start permission condition and a start prohibition condition is performed based on the check result. In the start permission condition, the engine can be started by the predetermined engine start operation. In the start prohibition condition, the engine cannot be started. 
       FIG. 1  is an outside view of the portable wireless key  1  according to the present embodiment. The portable wireless key  1  includes an emergency key  2  and a wireless key body  3  for holding the emergency key  2 . The emergency key  2  is a mechanical key for directly locking/unlocking the door of the vehicle through a key slot of the door. The emergency key  2  is inserted and held in an accommodation space  31  of the wireless key body  3 . 
     The emergency key  2  includes a key plate portion  2 A and a key grip portion  2 B. The key plate portion  2 A is to be inserted in the key slot of the vehicle. The grip portion  2 B is located at an end of the key plate portion  2 A. The grip portion  2 B has a ring portion  2 C as a first hook. The ring portion  2 C is located outside the wireless key body  3  under a condition that the key plate portion  2 A is held in the accommodation space  31 . Specifically, the emergency key  2  is held in the wireless key body  3  in such a manner that the grip portion  2 B projects from an outer side surface  30  of the wireless key body  3 . 
     The wireless key body  3  is shaped like a box with a smooth contour. Specifically, the wireless key body  3  has a substantially cube shape with chamfered corners. The accommodation space  31  for the emergency key  2  extends from an end of the short side along the long side of the wireless key body  3 . The emergency key  2  is held in the wireless key body  3  by inserting the key plate portion  2 A in the accommodation space  31  in a length direction of the long side. The accommodation space  31  has a key cut engagement receiver (not shown) engageable with a key cut of the key plate portion  2 A. An engagement between the key cut of the key plate portion  2 A and the key cut engagement receiver of the accommodation space  31  forms a temporary retaining condition (under a lock release condition described later, the emergency key  2  can be pulled out by force above a certain level). 
     As shown in  FIGS. 2A and 2B , the wireless key body  3  is divided into two in its thickness direction. An upper case body  3 U and a lower case body  3 D are aligned and joined together. An operation section  39  including an operation portion used to lock/unlock the door is located on a main surface of the wireless key body  3 . A controller connected to the operation section  39  and a wireless transceiver controlled by the controller are incorporated in the wireless key body  3 . Since an electrical configuration of such a portable wireless key  1  is known, an explanation of the electrical configuration is omitted. 
     By the way, in the portable wireless key  1  according to the present invention, the wireless key body  3  has a protrusion action portion  32  for performing a protrusion action in response to one push to an operation surface  30 P. The operation surface  30 P is located at a predetermined position on the outer side surface  30  to define the outer side surface  30 . The protrusion action causes the protrusion action portion  32  to protrude outward from the wireless key body  3 . As a result of the protrusion action, a hook  33  of the protrusion action portion  32  held in the wireless key body  3  is exposed outside and becomes available as a second hook with the emergency key  2  held in the wireless key body  3 . 
     Below, the portable wireless key according to the first embodiment is described in detail with reference to  FIGS. 2A ,  2 B and  FIGS. 3A ,  3 B.  FIGS. 2A ,  2 B are diagrams for explaining the protrusion action of the portable wireless key.  FIGS. 3A ,  3 B are diagrams illustrating exploded views of  FIGS. 2A ,  2 B, respectively. 
     According to the first embodiment, the protrusion action portion  32  includes a rotation member  321  and a rotation axis member  322  for rotatably fixing the rotation member  321  to the wireless key body  3 . The rotation member  321  extends in a direction perpendicular to a rotation axis of the rotation axis member  322  and has end portions  32 A and  32 B. An engagement receiver  34 , engageable with an engagement portion  35  of the wireless key body  3 , and the hook  33  are formed at the end portion  32 A. The engagement receiver  34  and the engagement portion  35  of the wireless key body  3  are engaged with each other to form an engagement condition that keeps the protrusion action portion  32  held in the wireless key body  3 . 
     The rotation axis member  322  is located between the end portions  32 A,  32 B and extends in the thickness direction of the wireless key body  3 . It is noted that the rotation axis member  322  is located closer to the end portion  32 A, where the hook  33  and the engagement receiver  34  are formed, than the end portion  32 B. 
     An outer surface of the end portion  32 B, where the hook  33  and the engagement receiver  34  are not formed, is exposed outside from the side of the wireless key body  3  to define the operation surface  30 P that can be pushed down toward the inside of the wireless key body  3 . When the push to the operation surface  30 P is performed, the end portion  32 B, where the operation surface  30 P is formed, is pushed down toward the inside of the wireless key body  3 , and the opposite end portion  32 A is moved up toward the outside of the wireless key body  3 . When the end portion  32 A is moved up toward the outside of the wireless key body  3 , the engagement condition between the engagement portion  35  of the wireless key body  3  and the engagement receiver  34  of the end portion  32 A is physically released so that the hook  33  can protrude from the inside to the outside of the wireless key body  3 . Thus, the hook  33  can catch a hook or the like. 
     The operation surface  30 P is exposed to the outer side surface  30  of the wireless key body  3  in such a manner that the push to the operation surface  30 P is allowable by only a special tool (e.g., emergency key  2 ) having a tip portion narrower than a predetermined width, such as a member (e.g., flathead screwdriver) having a width equal to or less than a width of the key plate portion  2 A of the emergency key  2 . 
     The rotation member  321  is a plate member and rotatably fixed by the rotation axis member  322 . The rotation axis member  322  is located closer to the inside of the wireless key body  3  than the rotation member  321 . A surface  320  of the rotation member  321  on the far side from the rotation axis member  322  defines the outer side surface  30  of the wireless key body  3 . The operation surface  30 P is a surface of the surface  320  on the end portion  32 B-side with respect to the rotation axis member  322 . A recess  30   p , engageable with the tip portion of the special tool (e.g., emergency key  2 ), is formed on the operation surface  30 P. The push to the operation surface  30 P is performed by pushing down the bottom of the recess  30   p  with the tip portion of the special tool (e.g., emergency key  2 ). The push is performed with the tip portion of the special tool received in the recess  30   p . Thus, the tip portion of the special tool is less likely to slip, so that the push can be easily performed. 
     An opening  30 L is formed in the wireless key body  3 . The rotation member  321  is held in the opening  30 L in such a manner that the surface  320  is exposed. The opening  30 L has a rotation allowable space  32 BS for allowing the end portion  32 B of the rotation member  321  to rotate toward the inside of the wireless key body  3  in response to the push to the operation surface  30 P. The rotation allowable space  32 BS is formed as a space between the upper case body  3 U and the lower case body  3 D. A wall portion (wall surface)  3 S is formed inside the wireless key body  3  and defines the rotation allowable space  32 BS. The wall portion  3 S serves as a movement limiting means for limiting the rotation to a predetermined angle position. In such an approach, the amount of protrusion of the opposite end  32 A, where the hook  33  is formed, is kept constant. Thus, an excessive protrusion is prevented so that the hook  33  can protrude by only an amount suitable for catching an object. 
     According to the present embodiment, the rotation member  321  is L-shaped as a whole. The L-shaped rotation member  321  is rotatably fixed to the rotation axis member  322  at the middle of its longitudinal portion  32 C. Specifically, the rotation member  321  is a L-shaped metal plate, and an axis insertion hole  32 D is formed at the middle of the longitudinal portion  32 C. The rotation axis member  322  is cylindrical and projects from an outer edge portion of the wireless key body  3  in the thickness direction of the wireless key body  3 . The rotation axis member  322  is inserted through a flat washer into the axis insertion hole  32 D. The axis insertion hole  32 D is fixed to a tip portion of the cylindrical rotation axis member  322  by hot swaging so that the axis insertion hole  32 D can be undetachable from the rotation axis member  322  and free to rotate (here, slidably rotate) with respect to the rotation axis member  322 . 
     Further, according to the present embodiment, the protrusion action portion  32  covers the opening  30 L, which is L-shaped and formed on the outer side surface  30  of the wireless key body  3 . The surface  320  of the protrusion action portion  32  is exposed from the opening  30 L and flush with the outer side surface  30  of the wireless key body  3  so as to define a part of the outer side surface  30 . The L-shaped opening  30 L according to the present embodiment is formed on the outer side surface  30  over one corner, out of four, of the wireless key body  3 . The L-shaped protrusion action portion  32  is fitted into the L-shaped opening  30 L. When the push to the operation surface  30 P of the protrusion action portion  32  is performed, a curve portion  33  curved from the longitudinal portion  32 C of the protrusion action portion  32  is moved up toward the outside of the wireless key body  3  so that a tip surface (here, a little inner surface of a tip of a curve tip portion  32 A) of a curve tip portion  32 A curved from the longitudinal portion  32 C can reach a position corresponding to an outer edge of the opening of the wireless key body  3 . The position is determined by the above movement limiting means. Thus, when the hook  33  catches an object, the object is held in a space between a curved inner surface of the L-shaped protrusion action portion  32  and the outer side surface of the wireless key body  3  facing the inner surface. Therefore, the object is less likely to be detached from the hook  33 . 
     According to the present embodiment, the hook  33  is configured as a curve portion curved from one tip portion of the longitudinal portion  32 C of the L-shaped protrusion action portion  32 . In other words, the hook  33  is an inner corner portion of the curve portion. The inner corner portion of the curve portion is configured as a recess portion recessed toward an outer corner portion of the curve portion. Thus, the hook  33  can surely catch the object. The recess portion has a curved surface. 
     According to the present embodiment, the engagement receiver  34  is located at the curve tip portion  32 A curved from one tip portion of the longitudinal portion  32 C of the L-shaped protrusion action portion  32  and formed as a groove or a hole recessed in the thickness direction of the wireless key body  3 . In contrast, the engagement portion  35  of the wireless key body  3 , engageable with the engagement receiver  34 , is formed as a projection projecting in the thickness direction of the wireless key body  3 . 
     According to the present embodiment, the protrusion action portion  32  is located at an end portion of the short side with respect to a substantially rectangular main surface of the wireless key body  3 , which is shaped like a box having a substantially cube shape. More specifically, the protrusion action portion  32  is located at the end portion of the opposite side from which the emergency key  2  is removed. The L-shaped protrusion action portion  32  has the longitudinal portion  32 C on the short side of the wireless key body  3  and is curved toward an adjacent long side. 
     Second Embodiment 
     Next, a portable wireless key according to a second embodiment of the present invention is described below with reference to  FIGS. 4A ,  4 B and  FIGS. 5A ,  5 B.  FIGS. 4A ,  4 B are diagrams for explaining a protrusion action of a portable wireless key according to the second embodiment.  FIGS. 5A ,  5 B are diagrams illustrating exploded views of  FIGS. 4A ,  4 B, respectively. 
     According to the second embodiment, the wireless key body  3  has a lock mechanism  21  for disabling the held emergency key  2  from being removed and a lock release operation portion  22  for releasing the lock mechanism  21 . The protrusion action portion  32  performs a protrusion action in response to a lock release action of the lock mechanism  21  so that the hook  33  of the protrusion action portion  32  can become available. Specifically, a lock condition of the lock mechanism  21  is released by one push to a predetermined position of the outer side surface  30  of the wireless key body  3  so that the emergency key  2  can become removable and that the hook  33  of the protrusion action portion  32  can be exposed outside. That is, an operation for causing the lock release action of the lock mechanism  21  causes the protrusion action of the protrusion action portion  32 . 
     It is noted that when the hook  33  of the protrusion action portion  32  is exposed outside as a result of the protrusion action, the lock mechanism  21  can return to the lock condition with the protrusion action portion  32  kept in the protrusion condition. That is, the hook  33  of the protrusion action portion  32  can be available with the emergency key  2  kept in the lock condition. 
     The lock mechanism  21  of the wireless key body  3  includes a rotation member (movable member)  211  and a rotation axis member  212  for rotatably fixing the rotation member  211  to the wireless key body  3 . The rotation member  211  has a first engagement portion  24  and a second engagement portion  26 . The first engagement portion  24  is engaged with an engagement receiver  23  of the emergency key  2  held in the wireless key body  3  to form an engagement condition that disables the held emergency key  2  from being removed. The second engagement portion  26  is engaged with an engagement receiver  25  of the protrusion action portion  32  to form an engagement condition that keeps the hook  33  of the protrusion action portion  32  held in the wireless key body  3 . 
     The lock release operation portion  22  releases the engagement conditions of the first engagement portion  24  and the second engagement portion  26  of the lock mechanism  21  at the same time in response to the push, thereby causing the protrusion action for exposing the hook  33  of the protrusion action portion  32  outside. According to the present embodiment, the lock release operation portion  22  corresponds to the rotation member  211 . 
     According to the present embodiment, the rotation member  211  extends in a direction perpendicular to a rotation axis of the rotation axis member  212 . The first engagement portion  24  is located at one end portion  21 A of the rotation member  211 . The second engagement portion  26  is located at the other end portion  21 B of the rotation member  211 . The rotation member  211  has the operation surface  30 P for the push, as the lock release operation portion  22 , at the end portion  21 B where the second engagement portion  26  is located. When the operation surface  30 P is pushed down toward the inside of the wireless key body  3 , the end portion  21 A, where the first engagement portion  24  is located, is moved up toward the outside of the wireless key body  3  so that the engagement condition between the first engagement portion  24  and the engagement receiver  23  can be released, and the opposite end portion  21 B, where the second engagement portion  26  is located, is pushed down toward the inside of the wireless key body  3  so that the engagement condition between the second engagement portion  26  and the engagement receiver  25  can be released. Thus, the protrusion action for exposing the hook  33  of the protrusion action portion  32  held in the wireless key body  3  outside can be caused. 
     The rotation member  211  is biased and held by a biasing means  27  such a spring so that the first engagement portion  24  and the second engagement portion  26  can be positioned in engagement angle positions where the first engagement portion  24  and the second engagement portion  26  form the respective engagement conditions. The push to the operation surface  30 P is applied against the biasing force of the biasing means  27 . When the push is removed, the first engagement portion  24  and the second engagement portion  26  return to the respective engagement positions. 
     The protrusion action portion  32  includes a rotation member  321  and a rotation axis member  322  for rotatably fixing the rotation member  321  to the wireless key body  3 . The rotation axis member  322  is located at the end portion  32 A of the rotation member  321 . The engagement receiver  25 , engageable with the second engagement portion  26  of the rotation member  211  of the lock mechanism  21 , is located at the opposite end portion  32 A. The end portions  32 A and  32 B are located opposite to each other in the direction perpendicular to the rotation axis of the rotation axis member  322 . The end portion  32 A is located further away from the lock mechanism  21  than the end portion  32 B. 
     In addition to the key cut, a groove or a hole is formed as the engagement receiver  23  in the emergency key  2 . The lock mechanism  21  has a projection fitted with the groove or the hole to form the engagement condition (fitted condition). That is, the projection serves as the first engagement portion  24  engageable with the engagement receiver  23 . According to the present embodiment, the emergency key  2  has a through hole  23  as the engagement receiver  23 . The through hole  23  is located at the tip portion of the key plate portion  2 A and penetrates from the inside to the outside of the wireless key body  3  under a condition that the key plate portion  2 A is held in the wireless key body  3 . In contrast, the lock mechanism  21  has a projection  24  as the first engagement portion  24 . The projection  24  projects from the outside to the inside of the wireless key body  3 . Under the lock condition, the projection  24  is inserted through the through hole  23  so that the emergency key  2  cannot be removed. When the end portion  21 A of the lock member  211 , where the first engagement portion  24  is formed, is moved up toward the outside of the wireless key body  3  by the push to the operation surface  30 P on the rotation member  211  of the lock mechanism  21 , the projection  24  is removed from the through hole  23 . As a result, the lock of the lock mechanism  21  is released so that the emergency key  2  can be removed. 
     According to the present embodiment, the protrusion action portion  32  of the wireless key body  3  has a craw-like engagement receiver as the engagement receiver  25 . The lock mechanism  21  has a craw-like engagement portion as the second engagement portion  26  engageable with the engagement receiver  25 . That is, craw portions of the engagement receiver  25  and the engagement portion  26  catch each other and are engaged with each other. Thus, even when the end portions  32 A,  32 B of the protrusion action portion  32  are pushed down toward the inside of the wireless key body  3 , the protrusion action portion  32  does not perform the protrusion action. Specifically, the rotation member  321  of the protrusion action portion  32  and the rotation member  211  of the lock mechanism  21  are arranged in a L-shape. Therefore, when the end portion  32 A of the protrusion action portion  32  is pushed, the craw portions of the engagement receiver  25  and the engagement portion  26  are engaged in the extension direction of the rotation member  211  to prevent the opposite end portion  32 B from moving up toward the outside of the wireless key body  3 . In contrast, when the end portion  32 B of the protrusion action portion  32  is pushed, force is applied in the extension direction of the lock mechanism  21  (in other words, in a direction toward the rotation axis member  322  with respect to the rotation member  211 ). Therefore, the rotation member  211  of the lock mechanism  21  does not move (rotate), and the protrusion action portion  32  does not move (rotate). On the other hand, when the operation surface  30 P on the rotation member  211  of the lock mechanism  21  is pushed so that the end portion  21 A of the lock mechanism  211 , where the second engagement portion  26  is formed, can be pushed down toward the inside of the wireless key body  3 , the engagement between the engagement receiver  25  and the engagement portion  26  is released so that the protrusion action for exposing the hook  33  of the protrusion action portion  32  outside can be caused. 
     According to the present embodiment, the rotation axis member  211  of the lock mechanism  21  is located between the end portions  21 A,  21 B of the rotation member  211  and extends in the thickness direction of the wireless key body  3 . The surface of the rotation member  211  exposed outside the wireless key body  3  on the protrusion action portion 32-side is configured as the operation surface  30 P that can be pushed down toward the inside o the wireless key body  3 . 
     According to the present embodiment, the rotation member  211  is a plate member and rotatably fixed by the rotation axis member  212 . The rotation axis member  212  is located closer to the inside of the wireless key body  3  than the rotation member  211 . A surface  210  of the rotation member  211  on the far side of from the rotation axis member  212  defines the outer side surface  30  of the wireless key body  3 . The operation surface  30 P is located at the end portion  21 B with respect to the rotation axis member  212 . 
     According to the present embodiment, a rotation allowable space  2 BS for allowing the end portion  21 B of the rotation member  211  of the lock mechanism  21  to rotate toward the inside of the wireless key body  3  in response to the push to the operation surface  30 P is formed in the wireless key body  3 . A wall portion (wall surface)  2 S is formed inside the wireless key body  3  and defines the rotation allowable space  2 BS. The wall portion  2 S serves as a movement limiting means for limiting the rotation of the rotation member  211  to a predetermined angle position. 
     According to the present embodiment, a rotation allowable space  3 BS for allowing the end portion  32 B of the rotation member  321  of the protrusion action portion  32  to rotate is formed in the wireless key body  3 . A wall portion (wall surface)  3 S is formed inside the wireless key body  3  and defines the rotation allowable space  3 BS. The wall portion  3 S serves as a movement limiting means for limiting the rotation of the rotation member  321  to a predetermined angle position. In such an approach, the amount of projection of the opposite end  32 A, where the hook  33  is formed, is kept constant. Thus, an excessive protrusion is prevented so that the hook  33  can protrude by only an amount suitable for catching an object. 
     According to the present embodiment, the axis insertion hole  32 D is formed at the end portion  32 A of the rotation member  321 , which is on the far side of the rotation member  321  from the lock mechanism  21 . The rotation axis member  322  is cylindrical and projects from the outer edge portion of the wireless key body  3  in the thickness direction of the wireless key body  3 . The rotation axis member  322  is inserted through the flat washer in the axis insertion hole  32 D, and the tip portion of the rotation axis member  322  is fixed to the axis insertion hole  32 D by hot swaging in such a manner that the axis insertion hole  32 D (the protrusion action portion  32 ) is undetachable from the rotation axis member  322  and free to rotate (here, slidably rotate) with respect to the rotation axis member  322 . 
     According to the present embodiment, a recess portion serving as the hook  33  is formed in the protrusion action portion  32 . The recess portion is formed at the end portion  32 B and located closer to the end portion  32 A than the engagement receiver  25 . The recess portion is recessed from the inside to the outside of the wireless key body  3 . Further, according to the present embodiment, the rotation member  321  of the protrusion action portion  32  covers a long-side opening portion  30 M 1  of an opening  30 L, which is L-shaped and formed on the outer side surface  30  of the wireless key body  3  over one corner. When the operation surface  30 P of the protrusion action portion  32  is pushed, the end portion  32 B of the rotation member  321  of the protrusion action portion  32  is moved up toward the outside of the wireless key body  3  so that each tip surface  33   a  of the recess portion as the hook  33  facing the inside of the wireless key body  3  can reach a position corresponding to an outer edge of the opening  30 M 1  of the wireless key body  3 . Thus, when the hook  33  catches an object, the object is held in a space between the inner surface (the wireless key body  3 -side) of the protrusion action portion  32  and the outer side surface of the wireless key body  3  located facing the inner surface. Therefore, the object is less likely to be detached from the hook  33 . It is noted that a short-side opening portion  30 M 2  is covered by the rotation member  211  of the lock mechanism  21 . 
     According to the present embodiment, the protrusion action portion  32  of the wireless key body  3  is located at an end portion of the short side of the wireless key body  3  with respect to a substantially rectangular main surface of the wireless key body  3 , which is shaped like a box having a substantially cube shape. More specifically, the protrusion action portion  32  is located at the end portion of the opposite side from which the emergency key  2  is removed. In contrast, the lock mechanism  21  is located on the long side of the wireless key body  3  where the accommodation space  31  is formed. Specifically, the lock mechanism  21  is located at an end portion of the long side closer to the protrusion action portion  32 . 
     As a result of the push for causing the protrusion action portion  32  to perform the protrusion action, the wireless key body  3  changes from the substantially cube shape to a shape having a projection due to the rotation action (swing action) of the lock mechanism  21 . However, when the push is removed, the wireless key body  3  returns to its original shape due to the biasing force of the biasing means  27 . Therefore, the operation to the lock mechanism does not spoil a design of the portable wireless key  1 . 
     As described above, according to the first and second embodiments, the portable wireless key  1  has a primary hook (first hook)  2 C and a secondary hook (second hook)  33 . The primary hook  2 C is exposed outside and always available under a condition that the emergency key  2  is held in the wireless key body  3 . The secondary hook  33  can be held inside the wireless key body  3 . Since the secondary hook  33  can be held inside whenever the secondary hook  33  becomes unnecessary, a design of the portable wireless key  1  is not spoiled. Furthermore, since the secondary hook  33  can be exposed outside by one push whenever the secondary hook  33  becomes necessary, the secondary hook  33  can be easily made available. 
     The lock mechanism similar to that described in the second embodiment can be added to the first embodiment. In this case, unlike the second embodiment, the lock mechanism can be independent of the protrusion action of the protrusion action portion  32 . 
     Modifications 
     The above embodiments can be modified in various ways. 
     For example, in the second embodiment, the engagement receiver  25  of the protrusion action portion  32  can be used as the hook  33 . In such an approach, the hook  33  of the second embodiment can be made unnecessary.