Patent Publication Number: US-7901253-B2

Title: Multiconductor jack and multiconductor plug

Description:
TECHNICAL FIELD 
     The present invention relates to a jack and a plug serving as electric connectors for carrying out electrically conductive connection, and more particularly, to a multiconductor jack and a multiconductor plug. 
     BACKGROUND ART 
     Many multiconductor plugs having three or four electrodes have conventionally been provided as plugs for use with portable music players, for example. However, because portable music players have in recent years come to be equipped with a great many functions, and also because of the need to provide multifunctional remote control capability and so forth, there is demand for further increase in the number of electrodes. 
     To meet such demand, Patent References Nos. 1 through 4, below, disclose multiconductor plugs and multiconductor jacks having five or more electrodes. 
     Patent Reference No. 1: Japanese Utility Model Registration No. 2545747 
     Patent Reference No. 2: Japanese Registered Utility Model No. 3078619 
     Patent Reference No. 3: Japanese Patent No. 3569658 
     Patent Reference No. 4: Japanese Unexamined Patent Application Publication No. 2002-134237 
     The multiconductor plugs disclosed in Patent Reference Nos. 1 through 4 achieve increased number of electrodes by more finely subdividing the surface of the post in the axial direction to increase the number of electrodes, providing an electrode at the tip of the post, or providing electrodes on the interior and exterior surfaces of the cylindrical portion (plug cover) disposed peripherally about the base portion of the post. 
     DISCLOSURE OF INVENTION 
     Problem to be Solved by the Invention 
     However, there being a limit to the amount by which the number of electrodes can be increased by more finely subdividing the post in the axial direction, further increase in electrode number cannot be expected. Furthermore, when attempting to provide electrodes on the interior and exterior surfaces of the plug cover, there has been the problem that this increases the diameter of the jack, making the structure complicated. Consequently, there is demand for a novel method of achieving increased number of electrodes that is different from the conventional methods of increasing the number of electrodes. 
     The present invention has been devised to solve the above problems, it being an object of the present invention to provide a multiconductor jack and a multiconductor plug that achieves an increased number of electrodes by a novel method. 
     Means for Solving the Problems 
     To solve the above problems, a multiconductor jack in accordance with the present invention is a multiconductor jack for connection to a multiconductor plug having an exposed electrode on a shaft portion and a flat electrode perpendicular to an axial direction, the multiconductor jack being characterized in that it comprises: a casing forming a space capable of being occupied by the shaft portion of the multiconductor plug; a first electrically conductive terminal having a contacting portion that faces the space and comes into electrically conductive contact with the electrode on the shaft portion of the multiconductor plug; and a second electrically conductive terminal having an elastic portion that extends in the axial direction of the multiconductor plug, and a contacting portion that comes into electrically conductive contact with the flat electrode of the multiconductor plug. 
     Furthermore, a multiconductor plug in accordance with the present invention is a multiconductor plug having a rod-shaped shaft portion for insertion in a multiconductor jack and a cylindrical flange portion provided at a base of the shaft portion, the multiconductor plug being characterized in that an annular flat electrode perpendicular to the axial direction of the shaft portion is formed at a tip side of the flange portion. 
     EFFECT OF THE INVENTION 
     Multiconductor jacks and multiconductor plugs in accordance with the present invention make it possible by a novel method to provide multiconductor jacks and multiconductor plugs having an increased number of electrodes. 
    
    
     BEST MODES FOR CARRYING OUT THE INVENTION 
     With reference to the drawings, embodiments of the present invention will be described in detail below. The present embodiment will be described in detail by way of the example of a six-electrode, single-headed plug and jack (φ 3.5). First, with reference to  FIGS. 1 and 2 , the configuration of a multiconductor plug according to the present embodiment will be described.  FIG. 1  is a perspective view of a multiconductor plug according to the present embodiment, and  FIG. 2  is a sectional perspective view of the multiconductor plug according to the present embodiment. 
     As shown in  FIGS. 1 and 2 , a multiconductor plug  10  comprises first through sixth electrodes  11   a  through  11   f  made of an electrically conductive metal, insulating collars  12   a  through  12   d  made of an insulating material for achieving isolation between the respective electrodes  11 , and a spacer  13 . Furthermore, these electrodes  11 , insulating collars  12 , and spacer  13  form a rod-shaped shaft portion  14 , this being the portion that is inserted in the jack, and a cylindrical flange portion  15  that is disposed at the base of the shaft portion  14 . 
     The rod-shaped first electrode (tip)  11   a  is disposed centrally in the shaft portion  14 , being exposed at the surface of the shaft portion  14  at the tip of the first electrode  11   a , and is in electrically conductive contact with a terminal of the jack, with the exposed portion serving as contacting portion. A cylindrical second electrode (ring)  11   b  is disposed exterior to the first electrode  11   a , with an insulating collar  12   a  serving as insulating layer being interposed therebetween. Similarly, disposed in order as one proceeds toward the exterior of the shaft portion  14  there are: an insulating collar  12   b , a third electrode (ring)  11   c , an insulating collar  12   c , a fourth electrode (ring)  11   d , an insulating collar  12   d , and a fifth electrode (ring)  11   e.    
     Furthermore, on the surface of the shaft portion  14 , exposed in order as one proceeds from the tip toward the base there are: the first electrode  11   a , the insulating collar  12   a , the second electrode  11   b , the insulating collar  12   b , the third electrode  11   c , the insulating collar  12   c , the fourth electrode  11   d , the insulating collar  12   d , and the fifth electrode  11   e , these five electrodes being formed just by the shaft portion  14  that is inserted in the jack. 
     Thus, although a plurality of electrodes are arranged in order in the axial direction of the shaft portion  14  in a manner similar to that which existed conventionally, in accordance with a novel method for increasing the number of electrodes the present embodiment is characterized in that the sixth electrode  11   f  is formed on a flat surface perpendicular to the axial direction on the tip side of the flange portion  15 . 
     The flange portion  15  is formed by the cylindrical spacer  13 , which serves as an insulating layer provided exterior to the fifth electrode  11   e , and the cylindrical sixth electrode  11   f , which is arranged so as to cover the outer periphery of the spacer  13 . The sixth electrode  11   f  has an annular flat surface perpendicular to the axial direction at the tip side of the flange portion  15 . When the plug is inserted in the jack, the annular flat electrode serves as a contacting portion which comes in contact with a terminal of the jack. 
     The width of this annulus of the sixth electrode  11   f  is set to 1.65 mm in the present embodiment. By thus giving the annular flat surface a certain amount of width, it is possible to reliably achieve electrically conductive contact with the electrically conductive terminal of the multiconductor jack, described below. A width of at least 0.5 mm at the annulus will permit achievement of satisfactory electrically conductive contact, and a width of at least 1.0 mm at the annulus will permit achievement of even more satisfactory electrically conductive contact. Note that since excessive width will cause the size of the plug and the jack to become too large, it is preferred that this width not exceed 3 mm. 
     Moreover, the portions exposed to the surface on the side opposite the shaft portion  14  serving as the first through fifth electrodes act as leads for those respective electrodes, and the portion on the side opposite the annular flat surface serving as the sixth electrode acts as a lead. 
     Next, referring to  FIGS. 3 and 4 , the configuration of the multiconductor jack according to the present embodiment will be described.  FIG. 3  is a perspective view of a multiconductor jack according to the present embodiment.  FIG. 4  is a perspective view, with hidden lines partially visible, of the multiconductor jack according to the present embodiment. 
     As shown in  FIGS. 3 and 4 , a multiconductor jack  20  has an insulating casing  21  made of a synthetic resin, and first through sixth electrically conductive terminals  23   a  through  23   f  disposed in predetermined places in the casing  21  so as to make electrically conductive contact with the electrodes  11  of the multiconductor plug  10 . The electrically conductive terminals  23  are made of electrically conductive metal. The electrically conductive terminals  23  are formed in such shapes as will cause them to press against the electrodes  11  due to elastic forces when the plug and the jack are connected to each other. 
     Specifically, when the multiconductor plug  10  is not inserted therein, the contacting portions of the electrically conductive terminals  23   a  through  23   e  are disposed such that they project somewhat into the space that will be occupied by the shaft portion  14  of the multiconductor plug  10 . When the multiconductor plug  10  is inserted therein, the contacting portions of the electrically conductive terminals  23   a  through  23   e  are pushed back by the electrodes  11   a  through  11   e  and are deformed, thereby generating elastic forces and causing the contacting portions to press against the electrodes  11   a  through  11   e.    
     The contacting portion  23   f   1  of the sixth electrically conductive terminal  23   f  projects somewhat, not into the aforementioned space that will be occupied by the shaft portion  14 , but into an exterior region at a plug insertion port  21   a  of the casing  21 . When the multiconductor plug  10  is inserted in the jack, the annular flat surface portion of the flange portion  15  will be disposed at a location where this contacting portion  23   f   1  protrudes, which will cause the contacting portion  23   f   1  to be pressed back and elastic forces to be generated, causing the contacting portion  23   f   1  to press against the sixth electrode  11   f . When the contacting portions of the electrically conductive terminals  23  are made to press against the electrodes  11  of the plug in this manner, electrically conductive contact can be maintained satisfactorily even in the event that external forces are applied to the plug and/or jack. 
     Here, the directions of the pressing forces that act between the first through fifth electrodes  11   a  through  11   e  located on the shaft portion  14  and the contacting portions of the first through fifth electrically conductive terminals  23   a  through  23   e  which face the space that will be occupied by the shaft portion  14  are perpendicular to the insertion direction (axial direction) of the multiconductor plug as was the case conventionally, but the direction of the pressing force that acts between the sixth electrode  11   f  and the contacting portion  23   f   1  of the sixth electrically conductive terminal  23   f  is parallel to the insertion direction of the multiconductor plug  10 . 
     As shown in  FIG. 4 , the sixth electrically conductive terminal  23   f  is arranged so as to extend in the insertion direction along the side face of the casing  20  in a region exterior to the second electrically conductive terminal  23   b  and the fourth electrically conductive terminal  23   d . One end of the sixth electrically conductive terminal  23   f , this being the tip end, is the contacting portion  23   f   1  that comes in contact with the sixth electrode  11   f , while the other end, this being the base end, is fixed to the casing  21  and serves as a lead segment  23   f   2 . 
     The sixth electrically conductive terminal  23   f  has an elastic portion  23   f   3  (accordion-like structure) that is wave-like in shape, peaks and valleys being arranged in alternating fashion in the insertion direction of the plug. Consequently, the sixth electrically conductive terminal  23   f  acts as an elastic member capable of extension and contraction in the insertion direction of the plug, with the lead segment  23   f   2  side acting as fixed end. Accordingly, when the multiconductor plug  10  is inserted in the multiconductor jack  20 , the contacting portion  23   f   1  is pushed back by the annular flat surface portion of the sixth electrode  11   f . Elastic forces generated by the accordion-like structure cause the contacting portion  23   f   1  to press against the sixth electrode  11   f , permitting electrically conductive contact to be maintained satisfactorily. 
     Such a sixth electrically conductive terminal might be formed by using a press die in a stamping operation to form electrically conductive sheet metal into a shape containing the wave-like structure, following which the contacting portion  23   f   1  might be formed by folding over a region in the vicinity of the tip at the contacting portion  23   f   1  side, and the lead segment  23   f   2  might be formed by folding a predetermined location at the base side. In addition, to make the contacting portion  23   f   1  and the sixth electrode  11   f  come into point contact with each other, the contacting portion  23   f   1  might be bent, following which the bent portion might further be made curved so that the contacting tip is formed in a convex shape. Forming the contacting portion  23   f   1  in a convex shape as described above will cause it to come into point contact with the electrode  11 , permitting stabilization of electrically conductive contact and achievement of a cleaning effect. 
     Such an electrically conductive terminal in which elastic forces are generated parallel to the axial direction of the plug facilitates electrode terminal layout design, since layout locations do not interfere with conventional electrically conductive terminals generating elastic forces in directions perpendicular to the axis, and makes it possible to provide multiconductor jacks having simple structures that occupy small volumes. 
     Next, the situation that exists when the multiconductor plug  10  is inserted in the multiconductor jack  20  will be described.  FIG. 5  is a sectional perspective view showing the situation that exists when the multiconductor plug and the multiconductor jack are connected to each other. In the situation that exists when the multiconductor plug  10  is inserted in the multiconductor jack  20  as shown in  FIG. 5 , the first electrode  11   a  is in contact with the first electrically conductive terminal  23   a , the second electrode  11   b  is in contact with the second electrically conductive terminal  23   b , the third electrode  11   c  is in contact with the third electrically conductive terminal  23   c , the fourth electrode  11   d  is in contact with the fourth electrically conductive terminal  23   d , and the fifth electrode  11   e  is in contact with the fifth electrically conductive terminal  23   e . At this time, as a result of insertion of the multiconductor plug  10 , the contacting portions of the electrically conductive terminals  23  are pushed back in directions perpendicular to the insertion direction, and the contacting portions of the electrically conductive terminals  23  press against the electrodes  11  in directions perpendicular to the axial direction of the multiconductor plug  10 . 
     Furthermore, annular flat surface at the tip of the sixth electrode  11   f  provided on the flange portion  15  of the multiconductor plug  10  is in contact with the sixth electrically conductive terminal  23   f . At this time, the direction of contact between the sixth electrode  11   f  and the sixth electrically conductive terminal  23   f  is parallel to the axial direction of the plug, and the sixth electrically conductive terminal  23   f , which has the above-described structure, is capable of extension and contraction in a direction parallel to the insertion direction of the plug, as a result of which elastic forces are generated in a direction parallel to the insertion direction of the plug. 
     Moreover, because the respective electrodes  11  according to the present embodiment are cylindrical in shape, having electrically conductive contacting surfaces in 360° with the electrically conductive terminals  23  of the jack, permitting electrically conductive contact to be achieved regardless of what rotational position the multiconductor plug  10  is in when it is inserted in the multiconductor jack  20  and permitting electrically conductive contact to be maintained despite any rotation of the multiconductor plug  10  relative to the multiconductor jack  20  following insertion. 
     As described in detail above, a multiconductor plug and a multiconductor jack in accordance with the present embodiment permit provision of a novel method for increasing the number of electrodes. Furthermore, by adopting a configuration such as that of the present embodiment, in which the sixth electrically conductive terminal  23   f  is made to extend and contract in a direction parallel to the insertion direction of the plug, causing generation of elastic forces, because the direction of extension and contraction is different from that of the other electrically conductive terminals  23 , this increases the degrees of freedom with which the sixth electrically conductive terminal  23   f  can be arranged and makes it possible to easily design the structure of the multiconductor jack. 
     Next, a variation on the present embodiment will be described with reference to the drawings. The present variation is characterized in that it is a multiconductor jack  30  of a water-resistant type.  FIG. 6  is a perspective view of the multiconductor jack according to the present variation.  FIG. 7  is a perspective view, with hidden lines partially visible, of the multiconductor jack according to the present variation.  FIG. 8  is a rear-side perspective view of the multiconductor jack according to the present variation. 
     While the multiconductor jack  30  according to the present variation is characterized in that it is of water-resistant design, since the basic structure and function are similar to those of the multiconductor jack  20  of the foregoing embodiment, description will be omitted with respect to structure that is identical, description being confined instead to structure that is peculiar to the present variation. 
     As shown in  FIGS. 6 through 8 , the multiconductor jack  30  according to the present variation has a casing  31  made of a synthetic resin, a seal  32 , and electrically conductive terminals  33   a  through  33   f  for making electrically conductive contact with the electrodes of the plug. Imaginary lines in  FIG. 6  indicate a mounting panel  50  in which the multiconductor jack  30  is inserted. 
     The seal  32  is a ring made of rubber that is arranged so as to be disposed peripherally about the jack insertion port of the casing  31  in a region interior to the contacting portion of the electrically conductive terminal  33   f  which projects outside the casing  31 . The seal  32  is sandwiched between the mounting panel  50  and the casing  31  when the multiconductor jack  30  is mounted to the mounting panel  50 , thereby increasing airtightness and ensuring water-resistance of the multiconductor jack  30 . 
     As shown in  FIGS. 7 and 8 , all of the lead segments of the electrically conductive terminals  33   a  through  33   f  are guided from the rear face of the casing  31  to the exterior. Mounted on the rear face of the casing  31  is a rear cover  34  having notches in portions corresponding to the leads. Adhesive is applied to this rear cover  34 , thereby ensuring that the jack interior will be water-resistant. 
     While embodiments of the present invention including variations thereon have been described above in detail, modes of carrying out the present invention are not limited to the foregoing embodiments, a great many variations being possible within the gist of the present invention. For example, the number of electrodes of the multiconductor jack and the multiconductor plug is not limited to six, it being possible to employ four, five, seven, or any other suitable number of electrodes so long as there are a plurality thereof. 
     Furthermore, although a planar flat surface has been employed as the flat electrode (sixth electrode) perpendicular to the axial direction in the present embodiment, it goes without saying that this is not limited only to perfectly planar flat surfaces, it being possible to achieve satisfactory contact with the electrically conductive terminal even with gently curved surfaces. Therefore, where the present specification refers to flat electrodes, this should be understood to include electrodes having gently curved surfaces. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a multiconductor plug according to the present embodiment. 
       FIG. 2  is a sectional perspective view of the multiconductor plug according to the present embodiment. 
       FIG. 3  is a perspective view of a multiconductor jack according to the present embodiment. 
       FIG. 4  is a perspective view, with hidden lines partially visible, of the multiconductor jack according to the present embodiment. 
       FIG. 5  is a sectional perspective view of a situation that exists when the multiconductor plug and the multiconductor jack according to the present embodiment are connected to each other. 
       FIG. 6  is a perspective view of a multiconductor jack according to a variation on the present embodiment. 
       FIG. 7  is a perspective view, with hidden lines partially visible, of the multiconductor jack according to the variation on the present embodiment. 
       FIG. 8  is a rear-side perspective view of the multiconductor jack according to the variation on the present embodiment. 
     EXPLANATION OF REFERENCE NUMERALS 
     
         
         
           
               10  Multiconductor plug 
               11  Electrode 
               12  Insulating collar 
               13  Spacer 
               14  Shaft portion 
               15  Flange portion 
               20  Multiconductor jack 
               21  Casing 
               23  Electrically conductive terminal 
               30  Multiconductor jack 
               31  Casing 
               32  Seal 
               33  Electrically conductive terminal 
               34  Rear cover