Patent Publication Number: US-6702619-B2

Title: Horizontal electric connector

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention belongs to a field of electric connectors that are horizontally mounted on a printed circuit board, etc., and relates to a structure for supporting electric contacts on an insulating housing. 
     2. Related Art 
     A horizontal electric connector is known as one of the above-mentioned horizontal electric connectors. This horizontal electric connector comprises an insulating housing, a first electric contact, which has a contacting part that is fixed on the insulating housing and contacts a counterpart contact, and a leg that extends from the contacting part, comes out of the insulating housing at the rear thereof and descends, and a second electric contact, which has a contacting part that is fixed on the insulating housing at a position lower than that of the first electric contact and contacts a counterpart contact, and a leg that extends from the contacting part, comes out of the insulating housing at the rear thereof and extends forwards along the bottom of the insulating housing (for example, refer to Japanese Utility Model unexamined publication gazette Heisei 1-160679). This horizontal electric connector is mounted on a printed circuit board by placing the horizontal electric connector on the printed circuit board, with the bottom of the horizontal electric connector facing a face of the printed circuit board, and soldering the connecting part at the top end of each leg onto a conductive part of the printed circuit board. When, as explained above, the leg of the second electric contact coming out of the insulating housing at the rear thereof is guided forwards, the distance between the connecting part of the second electric contact and the connecting part of the first electric connector can be made greater in comparison with a case wherein the leg of the second electric connector, which is coming out of the insulating housing at the rear thereof, is made to descend directly. Accordingly, even if the electric connector is subjected to a force in the front-rear direction by insertion or removal of a counterpart electric connector, the forces to which the connecting parts are subjected by the force will be reduced, and moreover, troubles such as short circuits caused by a solder waste or the like caught between the connecting parts can be prevented. 
     In the case of the above-mentioned horizontal electric connector, the length of the second electric contact from the part fixed to the insulating housing to the connecting part is longer in comparison with a case wherein the second electric contact descends directly at the rear of the insulating housing. Because of this, the leg tends to be deformed due to external forces. If the leg is deformed, the bottom of the leg and the bottoms of legs of other second electric contacts will become irregular to each other, losing the coplanarity, or increasing the possibility of defective connection and short circuit. Herein, obtaining the coplanarity means that the faces of the electric contacts, which contact a printed circuit board or the like, constitute a single plane. 
     SUMMARY OF THE INVENTION 
     The present invention was made in view of these points, and one objective of the invention is to provide a horizontal electric connector that can stably obtain the coplanarity of the second electric contacts and reliably prevent defective connection and short circuit by supporting the leg of the second electric contact on the bottom of the insulating housing and preventing deformation of the leg in both the height direction and the width direction. 
     To accomplish the above-mentioned objective, the horizontal electric connector according to the present invention comprises an insulating housing having a front, a rear and a bottom, a first electric contact, which has a contacting part that is press-fitted into the insulating housing from the rear and contacts a counterpart conductive part, and a leg that extends from the contacting part, comes out of the insulating housing at the rear thereof and descends, a second electric contact, which has a contacting part that is press-fitted into the insulating housing from the rear at a position lower than that of the first electric contact and contacts a counterpart conductive part, and a leg that extends from the contacting part, comes out of the insulating housing at the rear thereof and extends forwards along the bottom of the insulating housing, and a leg supporting part, which is provided on the bottom of the insulating housing and into which the leg of the second electric contact is press-fitted from the rear. 
     When this horizontal electric connector is placed in such a way that its bottom faces a printed circuit board or the like, and the connecting parts at the top ends of the legs of the first electric contact and the second electric contact are soldered onto the printed circuit board or the like, the horizontal electric connector will be mounted onto the printed circuit board or the like. In this case, as the leg of the second electric contact extends forwards along the bottom, even if the horizontal electric connector is subjected to a force in the front-rear direction, the forces to which the connecting parts will be subjected will be reduced, and moreover, troubles, such as short circuit caused by a solder waste or the like caught between the connecting parts will be prevented. Furthermore, as the leg of the second electric contact is press-fitted into the leg supporting part on the bottom of the insulating housing from the rear, the leg will hardly undergo deformation in the height direction and the width direction. As a result, the coplanarity of the second electric contacts will be obtained reliably and defective connection and short circuit will be prevented. 
     Accordingly, the horizontal electric connector according to the present invention can reduce the force to which the connecting parts are subjected when the connector is subjected to a force in the front-rear direction because the leg of the second electric contact extends along the bottom of the connector. Moreover, the horizontal electric connector of the present invention can prevent occurrence of troubles such as a short circuit between connecting parts due to a solder waste, etc. As the leg of the second electric contact is supported on the bottom of the insulating housing, the leg hardly undergoes deformation in the height direction and the width direction, and the coplanarity of the second electric contacts can be obtained stably, and defective connection and short circuit can be prevented reliably. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of an embodiment of the horizontal electric connector according to the present invention. 
     FIG. 2 is a front view of the embodiment of the horizontal electric connector. 
     FIG. 3 is a bottom view of the embodiment of the horizontal electric connector. 
     FIG. 4 is a side view of the embodiment of the horizontal electric connector. 
     FIG. 5 is an enlarged view of the embodiment of the horizontal electric connector. It is sectioned longitudinally and seen from its side. 
     FIG. 6 is an enlarged perspective view of a portion around the leg supporting part of the embodiment of the horizontal electric connector. It is seen from the lower front. 
     FIG. 7 is an enlarged perspective view of a portion around the leg supporting part of the embodiment of the horizontal electric connector. It is seen from the lower rear. 
     FIG. 8 is an enlarged front view of a portion around the leg supporting part of the embodiment of the horizontal electric connector. 
     FIG. 9 is an enlarged bottom view of a portion around the leg supporting part of the embodiment of the horizontal electric connector. 
     FIG. 10 is an enlarged perspective view of the second electric contact of the embodiment of the horizontal electric connector. 
     FIG. 11 is a perspective view of the insulating housing of the embodiment of the horizontal electric connector. 
     FIG. 12 is an enlarged perspective view showing the second electric contact being assembled into the insulating housing of the embodiment of the horizontal electric connector. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION 
     In the following, some embodiments of the present invention will be described. FIG.  1  through FIG. 4 show a horizontal electric connector  100  being the embodiment. This electric connector  100  is a card-edge connector which is to be horizontally mounted on a printed circuit board  200 , and the top end of an IC card or the like will be inserted, in a direction almost in parallel with the printed circuit board  200 , into the electric connector  100  through an insertion port that opens in one end of the electric connector  100 . 
     In FIG.  1  through FIG. 4,  110  denotes an insulation housing that is formed of an insulating material such as resin. A chamber  111  is formed in this insulating housing  110 . The chamber  111  is open rearwards. A receiving port  111   a  for receiving an IC card or the like, which is through to the chamber  111 , is formed at the front of the insulating housing  110 . A first electric contact  120  and a second electric contact  130  are press-fitted into the insulating housing  110  from the rear thereof. In this way, portions of the first electric contact  120  and the second electric contact  130  that are exposed forwards through the receiving port  111   a  are reduced. At least a pair of the first electric contact  120  and the second electric contact  130  are provided, and the first electric contact  120  is press-fitted on an upper side and the second electric contact  130  on a lower side, respectively. 
     As shown in FIG. 5, the first electric contact  120  is provided with a contacting part  121  and a leg  122 . The contacting part  121  is press-fitted into the insulating housing  110  from the rear thereof and protrudes into and is exposed in the chamber  111  where it contacts a counterpart conductive part being a conductive part of an IC card or the like. A wider press-fitting part  121   a  is formed in the contacting part  121 , and this press-fitting part  121   a  is press-fitted into a press-fitting groove  112  on the insulating housing  110 . The leg  122  extends from this contacting part  121 , comes out of the insulating housing  110  at the rear thereof and descends. A connecting part  122   a , which is to be soldered onto the printed circuit board  200 , is formed at the bottom free end of the leg  122 . The second electric contact  130  is provided with a contacting part  131  and a leg  132 . The contacting part  131  is press-fitted into the insulating housing  110  from the rear thereof, at a position that is lower than that of the first electric contact  120 , and protrudes into and is exposed in the chamber  111  where it contacts a counterpart conductive part being a conductive part of the IC card or the like. A wider press-fitting part  131   a  is formed in the contacting part  131 , and this press-fitting part  131   a  is press-fitted into a press-fitting groove  112  of the insulating housing  110 . The leg  132  extends from the contacting part  131 , comes out of the insulating housing  110  at the rear thereof, and extends forward along the bottom  113  of the insulating housing  110 . A connecting part  132   a , which is to be soldered onto the printed circuit board  200 , formed at the bottom free end of the leg  132 . 
     As shown in FIG.  6  through FIG. 9, a leg supporting part  140 , into which the leg  132  of the second electric contact  130  is press-fitted from the rear, is provided on the bottom  113  of the insulating housing  110 . The leg  132  of the second electric contact  130  comes out of the insulating housing  110  at the rear thereof, extends forward along the bottom  113  of the insulating housing  110 , and then descends away from the bottom  113  downward, and a connecting part  132   a  is formed at the bottom free end of the leg  132 . Protruding parts  134 , which protrude on both sides in the width direction, are formed in the part of the leg  132 , which is along the bottom  113  of the insulating housing  110 . As shown in FIG.  9  and FIG. 10, the protruding parts  134  on both sides may be formed at the same position in the front-rear direction or may be staggered from each other in the front-rear direction. The leg supporting part  140  is provided with a left vertical wall  141  and a right vertical wall  142 , which respectively contact faces  134   a  in the width direction of the protruding parts  134 , as well as horizontal walls  143 ,  144 , which extend sidewise from the vertical walls  141 ,  142  and contact the bottoms  134   b  of the protruding parts  134  and are apart from each other by a distance d, which is not less than the width w of the descending part  132   b  of the leg  132  (namely d≧w). 
     As shown in FIG.  5  through FIG. 9, a guide groove  113   a,  which holds the leg  132  of the second electric contact  130 , is formed in the bottom  113  of the insulating housing  110 , and the leg supporting part  140  is formed on this guide groove  113   a.  The leg supporting part  140  is provided in the front part of the bottom  113  of the insulating housing  110 . In other words, the guide groove  113   a  having a U-shaped section is formed in the insulating housing  110  from the rear face to the front face of the insulating housing  110 . The width of the guide groove  113   a  corresponds to the distance from the face  134   a  of one protruding part  134  of the leg  132  to the face  134   a  of the other protruding part  134 . In the front part of the guide groove  113   a,  the left and right vertical walls of the guide groove  113   a  constitute the left and right vertical walls  141 ,  142  of the leg supporting part  140 . Moreover, at the bottoms of the left and right vertical walls of the guide groove  113   a,  horizontal walls extend towards the opposing vertical walls, and the top ends of these horizontal walls are apart by the distance d, which is not less than the width w of the descending part  132   b  of the leg  132 . These horizontal walls constitute the horizontal walls  143 ,  144  of the leg supporting part  140 . 
     Accordingly, when the horizontal electric connector  100  according to the embodiment is placed on the printed circuit board  200  in such a way that the bottom  113  of the connector  100  faces the board  200 , and the connecting parts  122   a ,  132   a  at the bottom free ends of the legs  122 ,  132  of the first electric connector  120  and the second electric connector  130  are soldered onto the printed circuit board  200 , the horizontal electric connector  100  will be mounted onto the printed circuit board  200 . In this case, as the leg  132  of the second electric contact  130  extends forward along the bottom  113 , even if the horizontal electric connector  100  is subjected to a force in the front-rear direction, the forces which the connecting parts  122   a ,  132   a  receive will be reduced, and troubles such as a short circuit between the connecting parts  122   a ,  132   a  due to a solder waste, etc. will be prevented. Moreover, as the leg  132  of the second electric contact  130  is press-fitted into the leg supporting part  140  from the rear at the bottom  113  of the insulating housing  110 , the leg  132  will hardly undergo deformation in the height direction and the width direction. Hence, the coplanarity of the second electric contacts  130  will be obtained reliably and a defective connection and a short circuit will be prevented. 
     The present invention includes embodiments of the horizontal electric connector wherein the portion of the leg of the second electric contact, which extends forwards along the bottom of the insulating housing, is linear. In contrast to them, in the horizontal electric connector  100  of the above-mentioned embodiment, the leg  132  of the second electric contact  130  first extends forwards along the bottom  113  of the insulating housing  110  and then descends away from the bottom  113  downwards, and the part of the leg  132  that extends along the bottom  113  of the insulating housing  110  is provided with protruding parts  134  that protrude on both sides in the width direction. Moreover, the leg supporting part  140  is provided with the left and right vertical walls  141 ,  142 , which contact the faces  134   a  in the width direction of the protruding parts  134 , and horizontal walls  143 ,  144 , which extend sidewise from the respective vertical walls  141 ,  142 , contact the bottoms  134   b  of the protruding parts  134   a  and are apart from each other by a distance that is not less than the width of the descending part  132   b  of the leg  132 . With this arrangement, as shown in FIG. 12, when the second electric contact  130  is to be assembled into the insulating housing  110 , if the second electric contact  130  is brought to the insulating housing  110  from the rear thereof, the descending part  132   b  of the leg  132  will pass between the horizontal walls  143 ,  144  of the leg supporting part  140  and move forwards, and the protruding parts  134  will be inserted into a space between the bottom  113  of the insulating housing  110  and the horizontal walls  143 ,  144  of the leg supporting part  140  and between the vertical walls  141 ,  142  of the leg supporting part  140 . Hence displacement of the protruding parts  134  in the height direction will be limited between the bottom  113  of the insulating housing  110  and the horizontal walls  143 ,  144  of the leg supporting part  140 , and displacement thereof in the width direction will be limited between the vertical walls  141 ,  142  of the leg supporting part  140 . 
     The present invention includes embodiments wherein the portion of the bottom of the insulating housing along which the leg of the second electric contact extends is formed flat in the width direction. In contrast to them, in the horizontal electric connector  100  of the above-mentioned embodiment, the guide groove  113   a  for holding the leg  132  of the second electric contact  130  is formed in the bottom  113  of the insulating housing  110 , and the guide groove  113   a  is provided with the leg supporting part  140 . With this arrangement, as shown in FIG. 12, when the second electric contact  130  is to be assembled into the insulating housing  110 , if the second electric contact  130  is brought to the insulating housing  110  from the rear, the leg  132  will be guided along the guide groove  113   a  into the leg supporting part  140 . Hence the workability of assembly is good, and deformation of the second electric contact  130  will be prevented during assembly. 
     The present invention includes embodiments wherein the leg supporting part is provided in the middle part or the rear part of the bottom of the insulating housing. In contrast to them, in the horizontal electric connector  100  of the above-mentioned embodiment, the leg supporting part  140  is provided in the front part of the bottom  113  of the insulating housing  110 . With this arrangement, as shown in FIG. 12, when the second electric contact  130  is to be assembled into the insulating housing  110 , if the second electric contact  130  is brought to the insulating housing  110  from the rear, the second electric contact  130  will be press-fitted into the leg supporting part in the last stage of the assembling procedure. Hence the workability of assembly is good, and the second electric contact  130  will be prevented from deformation during assembly. 
     In the above-mentioned embodiment, the present invention was described by applying the invention to a card-edge connector into which or from which an IC card or the like is inserted or extracted. The present invention can also be applied, for example, to male or female horizontal electric connectors into which or from which a counterpart electric connector is inserted or extracted. In such a case, the conductive part of the counterpart is a male or female electric contact of the counterpart electric connector. Moreover, the present invention is extensively applicable to horizontal electric connectors having a structure wherein the electric contacts are press-fitted into the insulation housing from the rear. Hence the present invention includes embodiments wherein the chamber and the receiving port of the above-mentioned embodiment are not provided. The present invention also includes embodiments wherein the insulating housing is provided with a plurality of the first electric contacts being arranged in an upper layer and a lower layer and the second electric contacts are press-fitted into the insulating housing from the rear at positions being lower than those of the first electric contacts. 
     With the description of these embodiments, the first horizontal electric connector, which was described in the summary of the invention, has been fully disclosed. Moreover, with the description of these embodiments, the second through fourth horizontal electric connectors, which will be described below, have been fully explained. 
     The second horizontal electric connector is a horizontal electric connector as recited in the above-mentioned first horizontal electric connector, wherein the leg of the second electric contact has a width and extends forward along the bottom of the insulating housing then descends away from the bottom downward, the part of the leg extending along the bottom of the insulating housing is provided with protruding parts which protrude on both sides in the width direction, and the leg supporting part is provided with a left vertical wall and a right vertical wall, which contact faces in the width direction of the protruding parts, and horizontal walls, which extend sidewise from the vertical walls and contact the bottoms of the protruding parts and are apart from each other by a distance which is not less than the width of the descending part of the leg. With this arrangement, when the second electric contact is to be assembled into the insulating housing, if the second electric contact is brought to the insulating housing from the rear, the descending part of the leg will pass between the horizontal walls of the leg supporting part to move forward, and the protruding parts will be inserted into a space between the bottom of the insulating housing and the horizontal walls of the leg supporting part and between the vertical walls of the leg supporting part. Hence deformation of the protruding parts will be limited in the height direction between the bottom of the insulating housing and the horizontal walls of the leg supporting part and in the width direction between the vertical walls of the leg supporting part. Accordingly, the present invention is applicable to a horizontal electric connector wherein a part descending from the bottom downward is provided at the forward end of the part of the leg of the second electric contact extending along the bottom of the insulating housing. 
     The third horizontal electric connector is a horizontal electric connector as recited in the above-mentioned first or second horizontal electric connector, wherein a guide groove for holding the leg of the second electric contact is formed in the bottom of the insulating housing, and the guide groove is provided with the leg supporting part. With this arrangement, when the second electric contact is to be assembled into the insulating housing, if the second electric contact is brought to the insulating housing from the rear, the leg will be guided into the leg supporting part along the guide groove. As the leg of the second electric contact can be guided smoothly into the leg supporting part along the guide groove, the workability of assembly is good and deformation of the second electric contact can be prevented during assembly. 
     The fourth horizontal electric connector is a horizontal electric connector as recited in any one of the above-mentioned first through third horizontal electric connectors, wherein the leg supporting part is provided in the front part of the bottom of the insulating housing. With this arrangement, when the second electric contact is to be assembled into the insulating housing, if the second electric contact is brought to the insulating housing from the rear, the second electric contact will be press-fitted into the leg supporting part in the final stage of the assembling procedure. Hence the workability of assembly is good, and deformation of the second electric contact at the time of assembly will be prevented.