Abstract:
A mechanical key for accommodation in a portable device for use in an electronic key system. The mechanical key is provided with a grip including a socket and a key plate fixed to the grip. The key plate includes a blade and a shank, which is inserted into the socket. The shank includes a first edge for abutting against the socket when the shank is inserted into the socket and a shoulder extending from the blade. The socket includes a guide for abutting against and guiding the first edge of the shank when the shank is inserted into the socket. The guide is mated with the first edge under pressure. The socket further includes a second edge for abutting against the shoulder when the shank is inserted into the socket. The second edge is mated with the shoulder under pressure.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to a mechanical key.  
         [0002]     A mechanical key includes a grip and a key plate, which is inserted into the grip. Such a mechanical key may be used, for example, in an electronic key system for vehicles. An electronic key system includes a portable device, which is provided with a communication function, and a lock controller, which communicates with the portable device. The portable device is carried by a user, and the lock controller is installed in a vehicle.  
         [0003]     When the user approaches the vehicle, the electronic key system establishes communication between the lock controller and the portable device, which is located outside the vehicle, to unlock a vehicle door. Since the electronic key system automatically unlocks the door, the user may enter the vehicle by just pulling the door knob.  
         [0004]     The portable device incorporates a battery and uses the battery power to perform communication with the lock controller. Thus, when the voltage of the battery becomes less than a predetermined value, the portable device cannot communicate with the lock controller. As a result, the door cannot be unlocked with the electronic key system. To cope with such a case, the portable device includes a mechanical key to mechanically lock and unlock the door. This enables the user to unlock the door with the mechanical key even when communication between the portable device and the lock controller is disabled.  
         [0005]     To improve portability, there is a demand for a more compact portable device. Thus, recent mechanical keys have become shorter. This has shortened the portion of the key plate that is inserted into the grip. As a result, when inserting the key plate into the grip, the key plate easily inclines relative to the grip, or the insertion direction. This makes it difficult to position the key plate relative to the grip, and the key plate may become loose.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention provides a mechanical key enabling ensured positioning of a key plate relative to a grip.  
         [0007]     One aspect of the present invention is a mechanical key provided with a grip including a socket. A key plate is fixed to the grip and has a thickness and a width. The key plate includes a blade and a shank, which is inserted into the socket in an insertion direction. The shank has a distal part. The socket of the grip includes a movement restriction portion for abutting against the shank of the key plate and restricting movement of the shank in a direction perpendicular to the insertion direction. The shank of the key plate includes a pivot restriction portion for restricting pivoting of the key plate about the distal part of the shank.  
         [0008]     A further aspect of the present invention is a mechanical key for accommodation in a portable device for use in an electronic key system. The mechanical key is provided with a grip including a socket. A key plate is fixed to the grip and has a thickness and a width. The key plate includes a blade and a shank, which is inserted into the socket in an insertion direction. The shank of the key plate includes a first edge, extending in the insertion direction, for abutting against the socket when the shank is inserted into the socket. The shank also includes a shoulder extending from the blade. The socket includes a guide for abutting against and guiding the first edge of the shank when the shank is inserted into the socket. The guide is mated with the first edge under pressure so as to restrict movement of the key plate. The socket also includes a second edge for abutting against the shoulder when the shank is inserted into the socket. The second edge is mated with the shoulder under pressure so as to restrict movement of the key plate.  
         [0009]     Other aspects and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:  
         [0011]      FIG. 1A  is a perspective view showing a mechanical key;  
         [0012]      FIG. 1B  is a perspective view showing a portable device that accommodates the mechanical key;  
         [0013]      FIG. 2A  is a plan view showing a key plate;  
         [0014]      FIG. 2B  is a partially enlarged view showing the key plate of  FIG. 2A ;  
         [0015]      FIG. 2C  is a side view showing the key plate;  
         [0016]      FIG. 3A  is a cross-sectional view of a grip;  
         [0017]      FIG. 3B  is a cross-sectional view taken along line  3 B- 3 B in  FIG. 3A ;  
         [0018]      FIG. 3C  is a cross-sectional view taken along line  3 C- 3 C in  FIG. 3B ;  
         [0019]      FIGS. 4A and 4B  are cross-sectional views taken along line  3 C- 3 C in  FIG. 3B  and showing the assembly of the mechanical key; and  
         [0020]      FIG. 5  is a schematic diagram showing the assembly of the mechanical key. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]     A preferred embodiment of the present invention will now be described with reference to the drawings. In the preferred embodiment, a portable device of an electronic key system includes a mechanical key  12 .  
         [0022]     Referring to  FIGS. 1A and 1B , the portable device of the electronic key system includes a case  11 . The mechanical key  12  is detachably attached to the case  11 . The case  11  accommodates a transceiver, a transponder, and a battery (none are shown). The transceiver communicates with a lock controller (not shown), which is arranged in a vehicle. When a malfunction or battery drainage occurs in the portable device, the mechanical key  12  is used, for example, for insertion into a key cylinder (not shown) to perform locking or unlocking.  
         [0023]     As shown in  FIG. 1A , the mechanical key  12  includes a grip  20  and a key plate  30 , which is fixed to the grip  20 . The grip  20  and the key plate  30  are made of metal. The grip  20  includes a socket  21 . A shank  31 , which is inserted into the socket  21 , is defined toward one end of the key plate  30 , and a blade  32  is defined toward the other end of the key plate  30 . The blade  32 , which includes a serrated groove  32   a,  is inserted into a key cylinder. In the preferred embodiment, the longitudinal direction of the key plate  30 , which is the direction the key plate  30  is inserted into the grip  20 , is referred to as the insertion direction D 1 . The direction perpendicular to the plane of the key plate  30  shown in  FIG. 1A  is referred to as the thicknesswise direction D 2 . The direction extending laterally across the key plate  30  as viewed in  FIG. 1A  is referred to as the widthwise direction D 3 .  
         [0024]     As shown in  FIG. 1B , one corner of the case  11  is cut out to define a grip support  13  for receiving the mechanical key  12 . Referring to  FIG. 1A , the grip  20  is formed so that the mechanical key  12  is L-shaped as a whole. The mechanical key  12  is detachable from the case  11 . The mechanical key  12  is formed so that when it is attached to the case  11 , the grip  20  is in correspondence with the grip support  13 . The portable device has the shape of a generally thin box as a whole.  
         [0025]     As shown in  FIG. 2A , the blade  32 , which includes the serrated groove  32   a,  extends toward one end of the key plate  30  in the insertion direction D 1 , and the shank  31 , which is inserted into the socket  21  of the grip  20  (refer to  FIG. 1A ), extends toward the other end of the key plate  30  in the insertion direction D 1 . Compared to the blade  32 , the shank  31  is reduced in size in the widthwise direction D 3 .  
         [0026]     As shown in  FIG. 2B , a shoulder  36 , which has inclined surfaces  33  opposed to each other, extends toward the blade  32  from the shank  31 . The inclined surfaces  33  of the shoulder  36  are linear so that the dimension of the shoulder  36  in the thicknesswise direction D 3  gradually increases toward the blade  32 . The inclined surfaces  33  of the shoulder  36  function as a pivot restriction portion for restricting pivoting of the key plate  30  about the shank  31 . Further, as shown in  FIG. 2C , one side of the shank  31  includes a plate recess  34  located near the blade  32 . The plate recess  34  extends in the widthwise direction D 3 . Guide abutment edges  35  are defined on the side of the shank  31  that includes the plate recess  34  (refer to  FIGS. 4A and 4B ).  
         [0027]     Referring to  FIGS. 3A and 3B , the socket  21  of the grip  20  has an opening  22 . In the opening  22 , a shoulder seat  23  is formed so that the distance between the surfaces defining the shoulder seat  23  increases in the widthwise direction D 3  toward the open end of the socket  21 . The ends of the shoulder seat  23  farther from the open end of the socket  21  define shoulder abutment edges  24 . The shoulder abutment edges  24  abut against the inclined surfaces  33  of the shoulder  36  in a manner that the shoulder abutment edges  24  are mated with the inclined surfaces  33  under pressure. That is, the inclined surfaces  33  of the shoulder  36  are press-fitted to the shoulder abutment edges  24  of the shoulder seat  23 . The press-fitting absorbs dimensional errors of the key plate  30  in the widthwise direction D 3 .  
         [0028]     The socket  21  includes guides  25 . Each guide  25  is defined by a slanted surface linearly extending between the two walls of the socket  21  that face toward the corresponding guide abutment edge  35  in a state in which the shank  31  is inserted into the socket  21 . The guides  25  guide the guide abutment edges  35  of the shank  31  during insertion of the key plate  30  into the socket  21 . Further, the guides  25  abut against the guide abutment edges  35  in a manner that the guides  25  are mated with the guide abutment edges  35  under pressure. That is, the guide abutment edges  35  are press-fitted to the guides  25 . The guides  25  function as a movement restriction portion for restricting movement of the key plate  30  in directions perpendicular to the insertion direction D 1 . In the preferred embodiment, the guides  25  restrict movement of the guides  25  in the thicknesswise direction D 2  and the widthwise direction D 3 . Further, the press-fitting of the guide abutment edges  35  to the guides  25  absorbs errors in the cross-sectional dimensions of the key plate  30 . That is, the press-fitting absorbs dimensional errors in the thicknesswise direction D 2  and the widthwise direction D 3 .  
         [0029]     In detail, referring to  FIGS. 3A and 3B , the guides  25  are each formed in the socket  21  to extend in the insertion direction D 1  from the wall that comes into contact with the distal end of the key plate  30  to the middle part of the socket  21 . Referring to  FIG. 3C , the guides  25  are formed at corners located between the surface of the socket  21  extending in the widthwise direction D 3  and facing toward the guide abutment edges  35  and each of the two surfaces extending from that surface in the thicknesswise direction D 2 . The guides  25  extends linearly at an angle of approximately 45° with respect to the thicknesswise direction D 2  and the widthwise direction D 3 .  
         [0030]     A tapered surface  26  extends diagonally toward the opening  22  from each guide  25 . During insertion of the key plate  30  into the grip  20 , when the distal part of the key plate  30  advances from a position free of the guides  25 , as shown in the state of  FIG. 4A , to a position having the guides  25 , as shown in the state of  FIG. 4B , the tapered surfaces  26  contact and guide the guide abutment edges  35  of the key plate  30 . As the guide abutment edges  35  abut against the guides  25 , the guides  25  press the key plate  30  against the wall of the socket  21  that is located on the opposite side of the guide abutment edges  35 . This positions and fixes the key plate  30  in the socket  21 .  
         [0031]     As shown in  FIG. 3B , holes  27  extends through the grip  20  in the widthwise direction D 3 . Further, a grip recess  28  is formed in the grip  20  extending in the widthwise direction D 3 . The holes  27  and the grip recess  28  are located between the shoulder seat  23  and the guides  25  in correspondence with the plate recess  34  of the key plate  30 . In a state in which the shank  31  of the key plate  30  is inserted into the socket  21 , a pin  29  ( FIG. 1A ) is inserted through the holes  27  and arranged between the plate recess  34  and the grip recess  28 . The pin  29 , which is inserted through the grip  20  and retained in the plate recess  34 , prevents the key plate  30  from moving out of the socket  21  in the insertion direction D 1  and holds the key plate  30  in the grip  20 .  
         [0032]     Referring to  FIG. 5 , in the mechanical key  12 , the guides  25  of the grip  20  restrict movement of the distal part of the shank  31  that is inserted into the socket  21 . Further, the inclined surfaces  33  of the shoulder  36  restrict pivoting of the key plate  30  about the distal part of the shank  31 . Thus, movement of the shank  31  of the key plate  30  in the thicknesswise direction D 2  and the widthwise direction is restricted.  
         [0033]     The preferred embodiment has the advantages described below.  
         [0034]     (1) When the shank  31  of the key plate  30  is inserted into the grip  20 , the guides  25  of the grip  20  restrict movement of the key plate  30  in directions perpendicular to the insertion direction D 1  (i.e., the thicknesswise direction D 2  and the widthwise direction D 3 ). Further, the inclined surfaces  33  of the key plate  30  restrict pivoting of the key plate  30  about the distal part of the shank  31 . Thus, movement of the shank  31  of the key plate  30  when inserted into the grip  20  is restricted. This ensures positioning of key plate  30  in the socket  21  and prevents the key plate  30  from becoming loose.  
         [0035]     (2) Movement of the key plate  30  in the thicknesswise direction D 2  is restricted by the guides  25 , and pivoting of the key plate  30  in the widthwise direction D 3  is restricted by the inclined surfaces  33  of the shoulder  36 . The guides  25  restrict movement of the shank  31 . The inclined surfaces  33  restrict pivoting of the key plate  30  at positions located closer to the blade  32  than the distal part of the shank  31 . Thus, movement of the key plate  30  in directions perpendicular to the insertion direction D 1  is restricted at different locations in the insertion direction D 1 . This ensures positioning of the key plate  30  with respect to the grip  20 .  
         [0036]     (3) When inserting the key plate  30  into the grip  20 , the guides  25  guide the guide abutment edges  35  of the shank  31  in the insertion direction D 1  of the key plate  30 . Thus, the key plate  30  is smoothly inserted into the socket  21 . This facilitates assembly of the mechanical key  12 . Further, the guide abutment edges  35  of the key plate  30  are mated with the guides  25  under pressure (press-fitted) in correspondence with the cross-sectional dimensions of the key plate  30 . This absorbs errors in the cross-sectional dimensions (dimensions in the thicknesswise direction D 2  and the widthwise direction D 3 ) of the key plate  30 .  
         [0037]     (4) The abutment of the inclined surfaces  33  of the shank  31  against the shoulder abutment edges  24  of the grip  20  restrict pivoting of the key plate  30  about the distal part of the shank  31 . Further, the shoulder abutment edges  24  of the grip  20  are mated with the inclined surfaces  33  under pressure (press-fitted) in correspondence with the dimensions of the key plate  30 . This absorbs dimensional errors of the key plate  30  in the widthwise direction D 3 .  
         [0038]     (5) The tapered surface  26  extends diagonally toward the opening  22  of the socket  21  from each guide  25 . When the key plate  30  is inserted into the grip  20 , each tapered surface  26  guides the distal part of the key plate  30 . Thus, the key plate  30  is smoothly inserted into the socket  21 .  
         [0039]     (6) The shoulder abutment edges  24  of the grip  20  abut against the inclined surfaces  33  of the key plate  30 , and the guide abutment edges  35  of the key plate  30  abut against the guides  25  of the grip  20 . In this manner, the grip  20  and the key plate  30  contact each other at the abutment edges  24  and  35 . Thus, the grip  20  and the key plate  30  are fixed to each other in an optimal manner even though they are made of metal, which is harder than resin.  
         [0040]     It should be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention. Particularly, it should be understood that the present invention may be embodied in the following forms.  
         [0041]     In the preferred embodiment, the tapered surfaces  26  are formed extending from the guides  25  toward the opening  22 . However, the tapered surfaces  26  are not necessarily required.  
         [0042]     In the preferred embodiment, the guides  25  are arranged on opposite sides of the wall extending in the widthwise direction D 3 . However, the guides  25  may take other forms as long as movement of the key plate  30  in directions perpendicular to the insertion direction D 1  of the shank  31  is restricted. For example, there may be only one guide  25 . Alternatively, the guides  25  may be arranged on opposite sides of a wall extending in the thicknesswise direction D 2 .  
         [0043]     In the preferred embodiment, the key plate  30  includes the inclined surfaces  33 , which are linear such that the distance between the inclined surfaces  33  gradually increase in the widthwise direction D 3  toward the blade  32 . However, the inclined surfaces  33  may have other forms as long as pivoting of the key plate  30  about the distal part of the shank  31  is restricted.  
         [0044]     In the preferred embodiment, the shoulder abutment edges  24  of the grip  20  that abut against the inclined surfaces  33  of the key plate  30  may take any form as long the shoulder abutment edges  24  abut against the inclined surfaces  33  and restrict pivoting of the key plate  30  about the distal part of the shank  31 . However, it is preferable that the shoulder abutment edges  24  be located as far as possible from the distal part of the shank  31 . This would space the shoulder abutment edges  24  from the pivoting center of the key plate  30  and position and fix the key plate  30  in the socket  21  in an optimal manner.  
         [0045]     In the preferred embodiment, the grip  20  and the key plate  30  are made of metal. However, the grip  20  and the key plate  30  do not have to be made of metal and may be made of, for example, resin.  
         [0046]     The present examples and embodiments are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalence of the appended claims.