Abstract:
Spectacles comprise endpieces provided with receiving portions. Attachable spectacle accessory comprises endpieces provided with connecting portions. The receiving portions have a surface which is substantially perpendicular to the surface of the lenses of the spectacles. A magnet is set in the receiving portion. The connecting portions have a surface which is attracted to the surface of the receiving portion. The connecting portion is made from a magnetic substance. The Attachable spectacle accessory is securely attached to the spectacles by magnetically attracting the receiving portions and the connecting portions with each other.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an attachable spectacle accessory mounting device for attaching an attachable spectacle accessory to spectacles. 
   2. Description of the Related Art 
   Conventionally, an attachable spectacle accessory is attached to spectacles using magnetic power. As shown in Japanese Unexamined Patent Publication (KOKAI) NO. 09-101489, the spectacles and the spectacle accessory have endpieces which are provided with attractive portions formed from a permanent magnet or magnetic material. The attractive portions of the spectacle accessory are attracted to the attractive portions of the spectacles by magnetic power, so that the spectacle accessory is attached to the spectacles. But in this structure the spectacles and the spectacle accessory have many parts so that it is not easy to fabricate. 
   Namely, it is preferable that the spectacles for attaching a spectacle accessory have the same structure as that of ordinary glasses in order to decrease the number of parts. Therefore, it is suggested that spectacles should be provided with a bridge made of a magnetic material, and the spectacle accessory should be provided with a connecting member which bridges a pair of the lenses, and the connecting member which has a magnet should be attached to the bridge of the spectacles by magnetic power. But in this structure, the magnet may not be connected to a predetermined place on the bridge, because the magnet is attracted to anyplace on the bridge. Further, undesirably the spectacle accessory can easily come off the spectacles, if the spectacles are pushed slightly because the spectacle accessory is not securely attached to the spectacles. 
   SUMMARY OF THE INVENTION 
   Therefore, an object of the present invention is to provide a spectacle accessory mounting device for spectacles, so that the spectacle accessory is easily attached to and taken off the spectacles, the spectacles accessory is attached securely to the spectacles, and the numbers of parts and complexity of the spectacles is reduced. 
   According to the present invention, there is a spectacle accessory mounting device for attaching a spectacle accessory to spectacles which have a pair of first lenses, and a bridge, made of a magnetic material, which couples the pair of first lenses. A connecting member, provided on the spectacle accessory, has a connecting surface which is connected to the bridge by magnetic power, and a positioning portion being engaged with a pair of rim elements of the first lenses when the spectacle accessory is attached to the spectacles. 
   The spectacle accessory comprises a pair of second lenses, and the connecting member which couples the pair of second lenses. The positioning portion projects toward the bridge when the spectacle accessory is being attached to the spectacles. 
   The bridge has an upper surface, which is substantially horizontal when the spectacles are used, and the positioning portion contacts the upper surface. Preferably the positioning portion, formed as one body, is the same length as that of the upper surface. 
   Preferably the positioning portion comprises a first tongue engaged with one of the rim elements and a second tongue engaged with another of the rim elements. 
   The positioning portion is connected to the bridge by magnetic power. Further, the connecting member has a permanent magnet. 
   The permanent magnet has an exposed surface, the exposed surface is exposed at, and is substantially flush with, the connecting surface. 
   The connecting surface, which is a back surface of the connecting member, is connected to a front surface of the bridge. 
   The bridge has a bottom surface, which is substantially horizontal when the spectacles are used. The connecting member has a third tongue which contacts the bottom surface and prevents the spectacle accessory from slipping off of the spectacles when the spectacle accessory is attached to the spectacles. 
   According to the present invention, spectacles comprise a pair of lenses and a bridge which couples the pair of lenses. The bridge is made of a magnetic material. 
   According to the present invention, a spectacle accessory comprises a connecting member. The connecting member has a connecting surface which is connected to a bridge, made of a magnetic material, of the spectacles by magnetic power, and a positioning portion (or portions) being engaged with a pair of rims elements of the lenses of the spectacles when the spectacle accessory is attached to the spectacles. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The objects and advantages of the present invention will be better understood from the following description, with reference to the accompanying drawings in which: 
       FIG. 1  is a perspective view of spectacles and a spectacle accessory of the first embodiment; 
       FIG. 2  is a perspective view of a connecting member of the spectacle accessory of the first embodiment; 
       FIG. 3  is a perspective view of the connecting member connected to abridge of the spectacles in the first embodiment; 
       FIG. 4  is a perspective view of a connecting member of the spectacle accessory of the second embodiment; and 
       FIG. 5  is a perspective view of a connecting member of the spectacle accessory of the third embodiment. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention will be described below with reference to the embodiments shown in the drawings. 
     FIG. 1  is a perspective view of spectacles  10  and sunglasses (an attachable spectacle accessory)  20  of the first embodiment. The spectacles  10  have a pair of lenses  11 ,  12 . The lenses  11 ,  12  are each held by frames (or rim elements)  13 ,  14 . The rim elements  13 ,  14  are connected by a bridge  15 . In the case of the framed glasses, the frames are the rim elements, and in the case of frameless glasses, the outer peripheries of the lenses are the rim elements. The rim element  13  is connected to a temple  17  through an endpiece  16 . The rim element  14  is connected to a temple  19  through an endpiece  18 . The bridge  15 , which is made of magnetic material, has a front surface  15   a , an upper surface  15   b  and a bottom surface  15   c . When the spectacles  10  are used, the front surface  15   a  is substantially perpendicular, and the upper surface  15   b  and the bottom surface  15   c  are substantially horizontal. Namely, the spectacles  10  are glasses which have an ordinary structure which is used conventionally except that the bridge  15  is made of magnetic material. 
   The spectacle accessory  20  has a pair of colored lenses  21 ,  22 . The lenses  21 ,  22  are each held by the frames (or rim elements)  23 ,  24 . The rim elements  23 ,  24  are bridged by a connecting member  26 . The connecting member  26  corresponds to the position of the bridge  15  of the spectacles  10  when the spectacle accessory  20  is attached to the spectacles  10 . 
     FIG. 2  is a back view which shows the connecting member  26  and  FIG. 3  is a front view which shows the connecting member  26  connected to the bridge  15  in the first embodiment. The connecting member  26  has a connecting surface  26   a . The connecting surface  26   a , which is a back surface of the connecting member  26 , is connected to a front surface  15   a  of the bridge  15 . The connecting member  26  has a permanent magnet  29 . The permanent magnet  29  has an exposed surface which is exposed at, and is substantially flush with, the connecting surface  26   a . The exposed surface of the permanent magnet  29  is provided at substantially the center of the connecting surface  26   a . Further, the exposed surface of the permanent magnet  29  is covered by a resin layer which has a thickness of about 0.3 mm in order to protect the permanent magnet  29  from scratches. 
   The connecting member  26  is provided with a positioning portion  27  which is composed of a first tongue  27   a  and a second tongue  27   b  on the upper side of the connecting member  26 . The first tongue  27   a  and the second tongue  27   b  project toward the bridge  15  and contact the upper surface  15   b , and further the first tongue  27   a  is engaged with the rim element  13  of the lens  11  and the second tongue  27   b  is engaged with the rim element  14  of the lens  12 , when the spectacle accessory  20  is attached to the spectacles  10 . 
   The connecting member  26  is provided with a third tongue  28  on the bottom side of the connecting member  26 . The third tongue  28  contacts the bottom surface  15   c  of the bridge  15  in order to prevent the spectacle accessory  20  from slipping off of the spectacles  10  when the spectacle accessory  20  is attached to the spectacles  10 . 
   In this embodiment, if the connecting surface  26   a  of spectacle accessory  20  is only brought near the front surface  15   a  of the bridge  15 , the connecting surface  26   a  attracts the bridge  15  magnetically, and then the spectacle accessory  20  is attached to the spectacles  10 . At this time, the connecting member  26  is connected to the predetermined position of the bridge  15  because the positioning portion  27  is engaged with a pair of the rim elements  13 ,  14 . Due to this, the spectacle accessory  20  is attached to spectacles  10  in the same state at all times. Further, if the spectacle accessory  20  is pushed, the spectacle accessory does not slip off of the spectacles  10 , because the three tongues  27   a ,  27   b  and  28  contact both surfaces  15   b ,  15   c  of the upper and bottom sections of the bridge  15 . 
   On the other hand, the spectacle accessory  20  is easily taken off the spectacles  10  merely by pulling the spectacle accessory  20  against the magnetic power. 
     FIG. 4  is a back view which shows a connecting member of a spectacle accessory of a second embodiment. The spectacle accessory mounting device of the second embodiment has the same structure as that of the first embodiment except that the positioning portion is formed as one body and the third tongue is not provided on the connecting member. Namely, as shown in  FIG. 4  the connecting member  26  is provided with an integral positioning portion  30  on the upper side of the connecting member  26 . The positioning portion  30  is substantially the same length as that of the upper surface  15   b  of the bridge  15 . The positioning portion  30 , has a contact surface  30   a  which contacts the upper surface  15   b  of the bridge  15 , and is engaged with the pair of the rim elements  13 ,  14 , when the spectacle accessory  20  is attached to the spectacles  10 . The spectacle accessory mounting device in this embodiment has a similar effect as that of the first embodiment even though it does not have the third tongue  28 , because the contact surface  30   a  is broader in this embodiment than in the first embodiment. 
     FIG. 5  is a back view which shows a connecting member of a spectacle accessory of a third embodiment. The spectacle accessory mounting device of the third embodiment has the same structure as that of the second embodiment except that the bridge  15  is also attracted to the positioning portion magnetically, namely the positioning portion  31  has a permanent magnet  32 . The permanent magnet  32  has an exposed surface which is exposed at, and is substantially flush with, the contact surface  31   a  which contacts the upper surface  15   b  of the bridge  15 . The exposed surface of the permanent magnet  32  is provided at almost the center of the contact surface  31   a . The spectacle accessory  20  is connected to the spectacles  10  more strongly in this embodiment than in the second embodiment because the bridge  15  is attracted by two magnets. 
   In the first, second, and third embodiments, it is easy to fabricate the spectacles  10 , because spectacles needn&#39;t be provided with a special structure for attaching the spectacle accessory  20 , except that the bridge is made of a magnetic material. Further, the spectacle accessory  20  is merely made of lenses, frames (if necessary) and a connecting member so that a lot of parts for fabricating the spectacle accessory  20  are not needed. 
   In the first, second, and third embodiments, the lenses of the spectacle accessory are colored lenses. However, positive lenses can be used as lenses for the spectacle accessory according to the present invention. Spectacles including negative lenses are used as glasses for presbyopia by combining a spectacle accessory having positive lenses. 
   Further, in the first, second, and third embodiments, spectacles have frames for holding the lenses. However, spectacles can have no frames for holding the lenses of the spectacles. If the spectacles do not have a frame, the positioning portion is engaged with a pair of lenses rims (rim elements) directly. 
   Although the embodiments of the present invention have been described herein with reference to the accompanying drawings, obviously many modifications and changes may be made by those skilled in this art without departing from the scope of the invention. 
   The present disclosure relates to subject matter contained in Japanese Patent Application No. 2002-153789 (filed on May 28, 2002) which is expressly incorporated herein, by reference, in its entirety.