Abstract:
A wire to board connector has improved contact reliability and includes a receptacle connector for mounting to a circuit board and a plug connector with a mating blade for insertion into an opening of the receptacle connector. Both connectors have shields that are formed around their exterior and the receptacle connector has an interior shield member that envelops the insertion opening of the receptacle connector. Individual connect legs are formed with this interior shield member and they are spaced apart from each other widthwise of the insertion opening. A contact spring is disposed within the interior of the receptacle connector to exert a contact force on the mating plug connector.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to board connectors, and more particularly to wire to board connectors with multiple contact points. 
     Hitherto, board connectors have been used to connect wires to printed circuit boards, as shown in Japanese Patent Application Laid-Open (Kokai) 2006-172824. Such a connector is mounted on the board and is engaged with a counterpart connector connected to the end of a cable. 
       FIG. 14  is a perspective view of a shield of such a conventional board connector. 
     The connector has a shell  871  that is made of metal and arranged to enclose the circumference of a rectangular housing configured that supports a plurality of conductive terminals, thus acting as a shield. The shell  871  has an opening  813 , inside of which is accommodated conductive terminal assemblies of the housing and into which is inserted a mating connector (not shown) from the front thereof. 
     A plurality of ground terminals  876  are formed on the lower surface of the shell  871  for connecting to the circuit board. Tongue-like pieces  875 , are disposed between adjacent ground terminals  876 . Each tongue piece is provided with a contact spring  874 , which contacts the metallic shell of the mating connector inserted into the opening  813 . The contact spring  874  has its rear end connected to the tongue piece  875 , and a front end which is a free end formed as a cantilever and elastically displaceable vertically. This structure allows the contact spring  874  to contact the metallic shell of the mating connector. A side ground terminal  878  is formed on each side face of the shell  871  for attachment to the circuit board. 
     SUMMARY OF THE INVENTION 
     In case of this conventional board connector, the contact spring  874  is a spring that extends in the insertion/removal direction of the mating connector. In order to enhance the contact force of the contact spring  874  to ensure good mating contact with the connector, it is necessary to increase the overall size of the contact spring  874 . This increases the size of the shell  871  and housing. This conventional connector cannot be miniaturized. 
     Therefore, an object of the present invention is to solve the above-mentioned problems encountered by the conventional board connector by providing a reliable board connector with a plurality of legs connected to the circuit board and a spring part configured to extend widthwise of the connector insertion opening that receives as the mating connector and which is supported by the legs at both ends thereof, the legs and spring part being formed at the insertion opening, thereby obtaining a sufficient contact force by way of a thinned spring part, maintaining a secure contact, and further maintaining a secure connection between the legs and the conductive pads of the circuit board, thereby providing high shielding and reduced size. 
     In order to achieve the above-mentioned object, the present invention provides a board connector comprising a housing having a circumference thereof defined by a top plate, a bottom plate, and side walls, and the housing having an opening that receives part of a mating connector, a shield member having at least a part thereof arranged forward of the bottom plate and configured to contact with a mating shield member while covering at least a part of the exterior of the housing, wherein the shield member comprises a plurality of legs connected to the circuit board and facing a lower surface of the bottom plate, and a spring part extending widthwise along the insertion opening, with both ends thereof supported by the legs, and wherein the spring part is elastically displaced, when the mating connector is inserted into the opening. 
     In accordance with another embodiment of the present invention, each of the legs is formed by bending down a projecting piece protruding from the opening shield member. 
     In a further embodiment of the present invention, the spring part comprises a projection arranged on a surface thereof. 
     In accordance with a still further embodiment of the present invention, the spring part comprises a guide part extending obliquely downward in a forward direction from a front end thereof. 
     In yet a further embodiment of the present invention, the spring part is elastically displaced downward when the mating connector is inserted into the insertion opening. 
     In accordance with a further embodiment of the present invention, a distance is provided between the spring part and the board and is set so the spring part does not contact the circuit board even when displaced downward. 
     In accordance with a still further embodiment of the present invention, each of the legs include a connecting leg part positioned below the opening shield member and configured to contact the circuit board, wherein the connecting leg part has a curved side shape and is formed, by folding, with a base part connected to the opening shield member and a free end. 
     In accordance with the present invention, the board connector is provided with a shield member, which is arranged at an insertion opening and is formed with a plurality of legs connected to the circuit board and a spring part extending widthwise of the insertion opening and having both ends thereof supported by the legs. This configuration permits the springs to obtain a sufficient contact force, while maintaining a secure contact by the elasticity of the thinned spring part of the board connector, and also maintaining a secure connection between the legs and the conductive land of the board, thereby providing a high shield property, allowing reduction in the entire height of the board connector, and enhancing the contact reliability. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a board connector of the present invention and a mating connector before being fitted together; 
         FIG. 2A  is a top view of the mating connector of  FIG. 1 ; 
         FIG. 2B  is a front elevational view of the mating connector of  FIG. 1 ; 
         FIG. 2C  is a bottom plan view of the mating connector of  FIG. 1 ; 
         FIG. 2D  is a side elevational view of the mating connector of  FIG. 1 ; 
         FIG. 3  is a perspective view of the mating connector constructed in accordance with the principles of the present invention, with the lower surface facing upward; 
         FIG. 4A  is a top plan view of the board connector constructed in accordance with the present invention; 
         FIG. 4B  is a front elevational view of the board connector of  FIG. 4A ; 
         FIG. 4C  is a side elevational view of the board connector of  FIG. 4A ; 
         FIG. 5  is an exploded view of the board connector of  FIG. 4A ; 
         FIG. 6  is a perspective view of the front face board connector of  FIG. 4A ; 
         FIG. 7  is the same view as  FIG. 6 , with a part thereof removed for clarity; 
         FIG. 8  is an enlarged detail view of the cutaway portion of  FIG. 7 ; 
         FIG. 9A  is a partial cross-sectional view of the board connector of  FIG. 4 , taken along line A-A in  FIG. 4 ; 
         FIG. 9B  is a partial cross-sectional view of the board connector of  FIG. 4 , taken along line B-B in  FIG. 4 . 
         FIG. 10  is a top plan view of the board connector and a mating connector prior to engagement; 
         FIG. 11A  is a partial cross-sectional view of the board connector of  FIG. 10 , taken along line U-U thereof; 
         FIG. 11B  is a partial cross-sectional view of the board connector of  FIG. 10 , taken along line V-V thereof; 
         FIG. 12  is a top plan view of the board connector and mating connector fitted together; 
         FIG. 13A  is a partial cross-sectional view of the mated connectors of  FIG. 12 , taken along line X-X thereof; 
         FIG. 13B  is a partial cross-sectional view of the mated connectors of  FIG. 12 , taken along line Y-Y thereof; and 
         FIG. 14  is a perspective view of a shell of a conventional board connector. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the drawings, reference numeral  1  represents a receptacle connector used as a board connector that is mounted to a circuit board  91 . A plug connector  101  serves as a mating connector in this embodiment. The plug connector  101  is connected to the end of a cable that houses a plurality of conductive wires  191  and is mated to the connector  1  so as to connect the cable and connector  1  together. 
     In this embodiment, the plug connector  101  may be intended to connect a flexible flat cable such as an FFC (Flexible Flat Cable), FPC (Flexible Printed Circuit), or rigid circuit board rather than a cable with conductive wires  191  having a circular cross section as shown in the figure. The board  91  on which the receptacle connector  1  is mounted is a printed circuit board included in an electronic device. The electronic device may include a personal computer, a cell phone, a PDA (Personal Digital Assistant), a digital camera, a video camera, a music player, a game machine, a vehicle-mounted navigation system, or the like, although it may be a device of any kind. 
     The receptacle connector  1  is mounted on a circuit board included in a small-size electronic device. The receptacle connector  1  may be a compact, low-profile board connector having maximum external dimensions of a width of about 20 mm, a depth of about 5.5 mm, and a height of 1 mm or less, and it includes a plurality of terminals  61  that are arranged widthwise with a pitch of 0.5 mm or less. 
     The plug connector  101  includes a housing  111  formed by an insulating material such as a synthetic resin, a terminal  161  comprised of a conductive material and loaded in the housing  111 , and a plug shield member  171  comprised of a thin plate of a conductive material and configured to cover at least a part of the exterior, or circumference, of the housing  111 . 
     The housing  111  includes an insertion part  115  inserted into an insertion opening  13  of the connector  1 . The insertion part  115  is a plate-shaped part that extends forward (downward in  FIG. 2A ) from the front surface of a body  112  of the housing  111  and has a plurality of terminal grooves  116  formed on its upper surface. The tip of each terminal  161  is received and exposed in each accommodating groove  116 . The terminals  161  are arranged widthwise in the connector  101  (horizontal in  FIG. 2A ) at a predetermined pitch at, for example, 0.5 mm or less. The rear end of each terminal  161  is retained by the body  112  of the housing  111  inside the body  112  and is further connected to a core lead of each conductive wire  191  inserted in the body  112  from behind (above in  FIG. 2A ). 
     The shield member  171  includes an upper surface shield member  172  covering at least a portion of the upper surface of the body  112  of the housing  111 , a side surface shield member  173  covering at least a portion of the side surface of the body  112  of the plug housing  111 , a lower surface shield member  174  covering at least a portion of the lower surface of the body  112  of the plug housing  111 , and an insertion shield member  175  covering at least a portion of the lower surface of the insertion part  115  of the housing  111 . The upper surface shield member  172 , the side surface shield member  173 , the lower surface shield member  174  and the insertion shield member  175  are connected to and conductive with each other. At least one projection  176  (four such projections in the figures) protruding downward is formed to be arranged on the insertion shield member  175 . 
     When the insertion part  115  is inserted into the insertion opening  13  of the connector  1  to fit the connector  101  to the connector  1 , the shield member  171  is connected to and conductive to a receptacle shield member  71  covering the circumference of a housing  11  of the receptacle connector  1 . More specifically, the insertion part shield member  175  contacts the insertion opening shield member  75 . 
     The receptacle connector  1  is provided with a housing  11  formed from an insulating material, a plurality of terminals  61  comprised of a conductive material and loaded in the housing  11 , and a receptacle shield member  71  that is comprised of a thin conductive plate and which covers a portion of the exterior of the housing  11 . 
     The terminal  61  may be stamped and formed. The terminal  61  has a tail part  62  that extends backward from the lower side and is connected to a signal pad in the surface of the board  91  such as soldering. It also has an upper arm  63  that extends forward from the upper side of the terminal body, and a lower arm  64  that extends forward from the lower side of the body. A contact  65  protrudes downwardly and is formed in the vicinity of the tip of the upper arm  63 . The terminal  61  has its body held in the housing  11 . The terminals  61  are arranged side-by-side widthwise of the connector  1  (horizontal in  FIG. 4A ) at a predetermined pitch of, for example, 0.5 mm or less. 
     The housing  11  includes a top plate  12  and a bottom plate  14  that extend parallel with each other and side walls  15  that extend vertically at both ends of the connector  1 , as well as connecting the top plate  12  and the bottom plate  14  to each other. A narrow slot-shaped insertion opening  13  extends widthwise of the connector  1 , and the opening  13  is defined by the top plate  12 , the bottom plate  14 , and the side walls  15 . A plurality of arm accommodating grooves  16  accommodate at least a part of the lower arm  64  of each of terminal  61  and are formed on the upper surface of the bottom plate  14 . As shown in  FIGS. 7 and 8 , the terminal body  61  is retained in the innermost wall part  11   a  of the housing  11 , and the lower arm  64  extends forward into the insertion opening  13  from the innermost wall part  11   a.    
     The receptacle shield member  71  may be integrally formed by stamping it from a metal plate and forming it. The receptacle shield member  71  includes an upper shield member  72  as an upper shield member covering a portion of the upper surface of the top plate  12  of the housing  11 , a side shield member  73  as a receptacle side shield member covering a portion of the side surface of the side wall  15  of the receptacle housing  11 , an insertion opening shield member  75  as a receptacle lower shield member partially arranged ahead of the bottom plate  14  of the receptacle housing  11 , and a connecting shield member  74  as a receptacle connecting shield member configured to extend in the direction of height at both ends of the connector  1  that connect the upper shield member  72  and the insertion opening shield member  75  to each other. The upper shield member  72 , the side shield member  73 , the insertion opening shield member  75 , and coupling shield member  74  are connected to and are conductive with each other. 
     The insertion opening shield member  75  is a slim, elastic thin plate member extending widthwise of the connector  1 , and is positioned ahead of the front edge of the bottom plate  14  at the front end of the insertion opening  13  (the lower end of  FIG. 4A ) and has both ends of it connected to the coupling shield member  74 . The insertion opening shield member  75  includes a leg part  76  that can be connected to a ground pad provided on the surface of the board  91  such as soldering, and a spring part  77  that extends widthwise of the insertion opening  13  and it includes both ends thereof supported by the adjacent legs  76 . The number of the legs  76  is arbitrary but it is preferred to have two or more legs. In  FIG. 5 , the number of the legs  76  is 8, and the number of the spring parts  77  may also be arbitrary as long as it is 1 or greater. In  FIG. 5 , the number of the spring parts  77  is four. 
     As shown in  FIGS. 7 &amp; 8 , auxiliary contacts  79  that extend backward are formed near both ends of the insertion opening shield member  75 . This auxiliary contact  79  is a cantilever-shaped member whose base is connected to the insertion opening shield member  75 . The auxiliary contacts  79  extend so as to cover a part of the upper surface of the bottom plate  14  and is pushed to come into contact with the insertion shield member  175  when the mating connector  101  is inserted into the insertion opening  13 . The auxiliary contacts  79  may be omitted if desired. 
     The leg  76  whose cross-section is shown in  FIG. 9A  is formed by bending down a projecting piece protruding ahead of the front end of the insertion opening shield member  75 . The leg  76  includes a connecting leg part  76   a  positioned below the insertion opening shield member  75 , and configured to abut the ground pad of the board  91 . In this embodiment, the connecting leg part  76   a  has a curved side shape that is folded and is spaced apart from the surface of the board  91 , and at a free end (the tip side of the projecting piece). This curved side shape keeps the connecting leg part  76   a  to be separated apart from the lower surface of the insertion opening shield member  75  rather than keeping them into close contact and thus a cavity portion  76   b  is formed therebetween. 
     In case the leg  76  is connected to the ground pad of the board  91  via soldering, molten solder comes into the portion between the lower surface of the connecting leg part  76   a  and the surface of the board  91 , which forms a solder fillet that is very strong. The upper surface of the connecting leg part  76   a  does not contact the lower surface of the body of the insertion opening shield member  75 , and the cavity portion  76   b  is formed therebetween. The presence of the cavity portion  76   b  prevents solder wicking. In other words, solder does not directly adhere to the upper surface of the insertion opening shield member  75  and/or the spring part  77 . 
     While the leg  76  is formed by bending down a projecting piece and folding the tip thereof to face backward so as to be positioned between the insertion opening shield member  75  and the board  91 , the leg  76  may also have a shape where the tip is bent to face downward as long as a predetermined height from the board is maintained. The projecting piece may also be formed to connect from the rear end side rather than the front end side of the insertion opening shield member  75 . 
     The spring part  77  is a thin plate member having a slim belt shape, and has both ends thereof supported by the legs  76 , thus functioning as both-sided plate spring and coming into contact with the insertion part shield member  175  of the insertion part  115  of the plug connector  101  inserted into the insertion opening  13 . As shown in  FIG. 9B , the spring part  77  has a lower surface thereof that is spaced apart from the surface of the circuit board  91 . The spring part  77  is thus elastically deformed and displaced downward when pushed downward by the insertion part shield member  175  of the mating connector when the insertion part  115  thereof is inserted into the insertion opening  13  of the board connector. A reaction force generated by the elastic deformation pushes the spring part  77  against the insertion part shield member  175 . This securely maintains a contact between the spring part  77  and the insertion part shield member  175 , thus surely maintaining electrical continuity between the insertion opening shield member  75  and the insertion part shield member  175 . 
     The distance between the lower surface of the spring part  77  and the surface of the board  91  is previously designed and set, for example, by adjusting the height of the projection  176 , to a certain degree so that the lower surface of the spring part  77  does not abut against the surface of the board  91  even when the spring part  77  is displaced downward when the mating connector insertion part  115  is inserted. This prevents the insertion part  115  from abutting against the surface of the circuit board  91  when mating. 
     The lower surface of the spring part  77  does not abut against the circuit board  91 . Thus, a conductive trace may be located on the circuit board  91  corresponding to the lower surface of the spring part  77 . In this embodiment, it is possible to wire a conductive trace in a range corresponding to the lower surface of the spring part  77  so that the conductive trace passes below the connector  1 , which enhances the degree of freedom in wiring of conductive traces and also the degree of freedom of board design. 
     The spring part  77  extends widthwise with a relatively large dimension relative to the depth of the insertion opening  13 . Thus, it is possible to increase the length of a portion of the spring part  77  elastically deformed to function as a spring, that is, the spring length. By increasing the spring length as required, it is possible to obtain a stable contact when mating. 
     The spring part  77  supported by the legs  76  functions as a two-sided plate spring and is more likely to reserve an elastic region than a one-sided plate spring, only one end of which is supported and provides a greater reaction force on elastic deformation. It is unnecessary to increase the plate thickness of the spring part  77  to obtain a high contact force. It is possible to form an insertion opening shield member  75  as a thin plate, thus making it possible to reduce the height of the receptacle connector. A sufficient contact force is obtained without increasing the displacement amount of the spring part  77 . It is thus unnecessary to set a wide range where the spring part  77  is freely displaceable vertically. This also reduces the height of the connector  1 . 
     By soldering the folded part  76  as a leg part onto the board, the spring part  77  is formed into a beam both ends of which are fixed and supported to obtain a greater contact force. 
     In the illustrated example, a guide part  77   a  configured to extend obliquely downward in a forward direction is connected to the front end of the spring part  77 . As shown in  FIG. 9B , the upper surface of the guide part  77   a  is a tilting surface that is tilted obliquely downward in a forward direction. When the insertion part  115  is inserted into the insertion opening  13 , the lower end of the insertion part  115  is guided by the tilting surface, which smoothly guides the insertion part  115  to be induced into the insertion opening  13 . 
     The cross section of the spring part  77  including the guide part  77   a  connected thereto forms a “chevron”-style shape shown in  FIG. 9B . The spring part  77  is less likely to bend with respect to the direction of bending (vertically in  FIG. 9B ) than without the guide part  77   a . This allows adjustment to increase the contact force of the spring part  77 . As described above, it is unnecessary to increase the plate thickness of the spring part  77  and set a wide range where the spring part  77  is displaceable in the direction of the height of the receptacle connector  1 , thereby making it possible to suppress the height of the receptacle connector  1 . 
     In this embodiment, while the cross-section of the spring part  77  has a “chevron” shape, the cross section may also have an arc shape. 
     A notch  78  is provided between the guide part  77   a  and each of the legs  76  supporting the both ends of the spring part  77 . By adjusting the size of the notch  78 , it is possible to adjust the dimension of the connecting part between the spring part  77  and the legs  76  and the dimension of the guide part  77   a  to adjust the elasticity of the spring part  77 . 
     The dimension of the guide part  77   a  and the tilting angle of the guide part  77   a  with respect to the spring part  77  may be set as required. For example, when a larger tilting angle of the guide part  77   a  with respect to the spring part  77  is set, the spring part  77  is less likely to be deformed so as to provide a greater contact force with the shield member of a counterpart connector. Furthermore, the guide part  77   a  may be omitted as required if unnecessary. 
     The receptacle connector  1  in  FIGS. 10-12  is a right-angle type connector and the connector  1  is mounted laterally on the circuit board  91  with the lower surface of the bottom plate  14  of the receptacle housing  11  facing the surface of the board  91 . The insertion opening  13  extends parallel with the board  91  and the front surface of the insertion opening  13  is substantially vertical with respect to the board  91 . 
     An operator manipulates the mating plug connector  101  with his or her fingers or the like and orients the front surface of the insertion part  115  of the connector  101  even with the insertion opening  13  of the connector  1 , as shown in  FIGS. 10 and 11 . 
     Next, the connector  101  is moved toward the connector  1 , and the insertion part  115  of the connector  101  is inserted in the insertion opening  13  of the connector  1 . The lower end of the insertion part  115  is guided by the tilting surface of the guide part  77   a  of the insertion opening shield member  75  and thus the insertion part  115  is smoothly inserted in the insertion opening  13 . 
     When the insertion part  115  of the plug connector  101  is inserted as deep as the innermost area of the insertion opening  13  of the connector  1 , the connector  101  and the connector  1  are fully engaged with each other as shown in  FIGS. 12 and 13 . 
     In this case, as shown in  FIG. 13A , the projection  176  formed on the insertion part shield member  175  abuts against the upper surface of the spring part  77  of the insertion opening shield member  75  to thereby displace the spring part  77  downward. 
     The projection  176  is desirably formed in a position corresponding to the center with respect to the width of the insertion opening  13  at each spring part  77 . Thus, the spring part  77 , both ends of which are supported by the legs  76 , is displaced to take a horizontally symmetrical shape and to exhibit an appropriate elasticity. 
     As shown in  FIG. 13A , even when the spring part  77  abuts against the projection  176  and is displaced downward, the lower surface of the spring part  77  does not abut the surface of the circuit board  91 . The spring part  7  produces a reaction force through elastic displacement. This reaction force pushes the spring part  77  onto the insertion part shield member  175 . This maintains a contact between the spring part  77  and the insertion part shield member  175  with certainty, thereby surely maintaining electrical continuity between the insertion opening shield member  75  and the insertion part shield member  175 . For example, even in case an external force such as torsion is exerted on the plug connector  101  via the wire  191 , the plug connector  101  in an elastically deformed shape follows the variation, thus surely maintaining electrical continuity between the insertion opening shield member  75  and the insertion part shield member  175 . 
     The contact part of the spring part  77  on the insertion part shield member  175  is a small portion of the projection  176  so that the contact pressure per unit area at the contact part becomes higher. This exerts a wiping operation to remove dirt or the like on the surface upon contact between the spring part  77  and the insertion part shield member  175 , which securely maintains electrical continuity with a reduced resistance, thereby more securely maintaining electrical continuity between the insertion opening shield member  75  and the insertion part shield member  175 . 
     In this embodiment, while the projection  176  is provided on the insertion part shield member  175 , the projection  176  may be formed to protrude upward on the upper surface of the spring part  77  of the insertion opening shield member  75  instead of the insertion part shield member  175 . 
     The plurality of the spring parts  77  (four in the illustrated example) and the projections  176  are formed so that the insertion opening shield member  75  and the insertion part shield member  175  come into contact with each other at multiple points. That is, multipoint contact is provided between the receptacle shield member  71  and the plug shield member  171 , thus stabilizing the ground contact resistance between the receptacle connector shield member  71  and the plug connector shield member  171 . 
     The spring part  77  produces an upward force, which exerts a downward force on the legs  76  supporting both ends of the spring part  77 . The connecting leg part  76   a  of the leg  76  is pushed against the ground pad of the board  91 . The connecting leg part  76   a  of the leg  76  prevents the solder-based connecting part between the connecting leg part  76   a  and the ground pad on the board  91  from being peeled off, thus surely maintaining electrical continuity between the receptacle shield member  71  and the board  91 . For example, even in case an external force such as torsion is exerted on the receptacle connector  1  via the wire  191  and the connector  101 , it is possible to surely maintain electrical continuity between the receptacle shield member  71  and the board  91 . 
     The plurality of legs  76  (eight in the illustrated example) are formed so that the receptacle shield member  71  and the board  91  come into contact with each other at multiple points. That is, multipoint contacts are provided between the receptacle shield member  71  and the board  91 , thus stabilizing the ground contact between the receptacle shield member  71  and the board  91 . 
     The receptacle connector  1  and its insertion opening shield member  75  contact the insertion part shield member  175  covering part of the lower surface of the insertion part  115  as well as a receptacle shield member  71  covering part of the receptacle housing  11 , while the legs  76  are connected to ground pads on the circuit board  91 . 
     This obtains a sufficient contact force by way of the thin spring part  77 , thus maintaining a secure contact with the insertion part shield member  175  of the plug connector  101  as well as a secure connection between the legs  76  and the ground pad on the board  91 , thereby providing a high shielding property and contact reliability. It is thereby possible to reduce the height of the receptacle connector  1 . 
     The spring part  77  or the insertion part shield member  175  includes the projection  176  formed on the surface thereof. When the spring part  77  or the insertion part shield member  175  abuts against the projection  176 , the spring part  77  is elastically displaced downward. A reaction force produced by the spring part  77  pushes the spring part  77  against the insertion part shield member  175 . This securely maintains a contact between the spring part  77  and the insertion part shield member  175 , thus surely maintaining electrical continuity between the insertion opening shield member  75  and the insertion part shield member  175 . 
     The spring part  77  includes the guide part  77   a  configured to extend obliquely downward in a forward direction from the front end thereof. This smoothly guides the insertion part  115  into the insertion opening  13 . The spring part  77  is less likely to be deformed, thus allowing adjustment to obtain a greater contact force. 
     The distance between the spring part  77  and the board  91  is set so that the spring part  77  does not come into contact with the board  91  even when displaced downward. This avoids a state where the spring part  77  is in contact with the board  91  and is not displaced further thus failing to obtain a predetermined elastic region. It is possible to wire a conductive trace in a range corresponding to the lower surface of the spring part  77  on the surface of the board  91 , thus enhancing the freedom of wiring of a conductive trace and freedom of design of the board  91 . 
     The leg  76  includes the connecting leg part  76   a  positioned below the insertion opening shield member  75  and configured to come into contact with the ground pad on the board  91 . The connecting leg part  76   a  has a curved side shape and the lower surface thereof is separated apart from the surface of the board  91  at a base side connected to the insertion opening shield member  75  and at a free end side, thus forming the cavity portion  76   b  between the upper surface of the connecting leg part  76   a  and the lower surface of the insertion opening shield member  75 . This forms a solder fillet in the part, thus increasing the strength of soldering between the leg  76  and the ground pad on the board  91  as well as preventing solder wicking on the shield member  75  or the spring part  77 . 
     The present invention is not limited to the above-described embodiments, and may be changed in various ways based on the gist of the present invention, and these changes are not eliminated from the scope of the present invention.