Abstract:
The present invention provides a connector assembly which allows the easy replacement of easily damaged female contacts, and which can be used in data transfer systems such as communications devices that transmit data signals at a high speed. The connector assembly comprises a first connector having a plurality of first boards which have conductors formed on the surfaces thereof, a second connector having a plurality of second boards which have conductors formed on the surfaces thereof, and a relay connector which is attached to the first connector or second connector. A plurality of female contacts having first female contact portions that contact the conductors of the first boards and second female contact portions that contact the conductors of the second boards are press-fitted in the relay connector.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a connector assembly used in data transfer systems such as communications devices that transmit data signals at a high speed. 
     BACKGROUND OF THE INVENTION 
     In connectors used in high speed data transfer systems, such as communications devices that transmit data signals at speeds exceeding 2 Gbps, the impedance of the signal paths inside the connector must be maintained at a uniform value. 
     An exemplary connector  101  that is used to maintain a uniform impedance is shown in  FIGS. 8 and 9 . This connector  101  comprises an insulating housing  110  and a plurality of boards  120  that are supported in a row in the housing  110 . Each board  120  is constructed from an insulating board material such as FR4, and a pattern comprising a plurality of signal conductors  121  and a plurality of ground conductors  122  is formed such that the ground conductors surround the signal conductors  121  with a specified distance retained between the respective conductors. The pattern of signal and ground conductors is disposed on the front and back surfaces of each board  120 . The signal conductors  121  extend from a first side  123  of the board  20  configured to mate with a mating connector (not shown in the figures) to a second side  124  of the board  120  with mounting pads  124  thereon and configured to be connected to another circuit board (not shown in the figures). The ground conductors  122  extend from points located slightly to the inside of the contacts on the first side  123  to the mounting pads on the second side  124 . A plurality of contacts  130  are disposed on the mounting pads at the second side  124  of the respective boards  120  to form an electrical connection to the signal conductors  121  and ground conductors  122 . 
     The housing  110  comprises a front housing portion  111  and an accommodating body  114 . The front housing portion  111  comprises a vertical wall  111   a  and a top  11   b  that extends rearward (to the left in  FIG. 8 ) from an upper end of the vertical wall  111   a . A plurality of slits  112  pass through the vertical wall  111   a  such that the contacts  123  of the respective boards  120  are passed through the slits  112 . Grooves  113   a  and  113   b  are respectively formed in protruding wall that extends forward from the lower end of the vertical wall  111   a  and from the upper end of the vertical wall  111   a  into which the lower ends and upper ends of the respective boards  120  are inserted. Furthermore, the accommodating body  114  comprises a platform portion  114   a  that extends in the forward-rearward direction, and a rear vertical wall  114   b  that extends upward from the rear end of the platform portion  114   a . A plurality of grooves  115  are formed in the platform part  114   a  to receive the second side  124  of the respective boards  120  having the mounting pads disposed thereon. A through-hole (not shown in the figures) is formed in each groove  115 , through which one of the contacts  130  connected to the signal conductors  121  and ground conductors  122  is passed. Furthermore, a plurality of grooves  116  are formed in the rear vertical wall  114   b , into which the contacts on the first side  123  of the respective boards  120  are inserted. Moreover, engaging posts  117  that engage with the top portion  111   b  of the front housing portion  111  are formed on the upper end surface of the rear vertical wall  114   b.    
     In the connector  101  shown in  FIGS. 8 and 9 , the contacts on the signal conductors  121  of the respective boards  120  at the first side  123  thereof are utilized as male type contacts, and are mated and connected with female type contacts (not shown in the figures) disposed on the side of the mating connector. The plurality of contacts  130  disposed on the mounting pads at the second side  124  of the respective boards  120  are connected to the circuit board. As a result, the impedance of the signal paths inside the connector  101  can be maintained at a uniform value, so that data signals can be transmitted at a high speed. 
       FIG. 10  shows a configuration in which multi-layer boards  301  and  302  are connected to each other by a connector assembly comprising a first connector  101  shown in  FIGS. 8 and 9  and a second connector  201  that is mated with this first connector  101 . 
     Specifically, in the first connector  101 , the signal conductors  121  formed on the first side  123  (see  FIG. 9 ) of the respective boards  120  are utilized as male type contacts, and are mated and connected with female type contacts  202  disposed in the second connector  201 . The male type contacts  202  of the second connector  201  are connected to the multi-layer board  301 . Moreover, the plurality of contacts  130  disposed on the second side  124  (see  FIG. 9 ) of the respective boards  120  are connected to the multi-layer board  302 . As a result, the impedance of the signal paths inside the connector assembly comprising the first connector  101  and second connector  201  can be maintained at a uniform impedance value, so that data signals can be transmitted at a high speed. 
       FIG. 11  shows a connector  401  in which a plurality of female contacts  425  are connected to the respective end parts of a plurality of boards  421 ,  422 ,  423  and  424 , and these female contacts  425  are secured inside a housing  410 . A plurality of signal conductors  421   a  and ground conductors  421   b  are formed on the surfaces of the respective boards  421 ,  422 ,  423  and  424 , and the female contacts  425  are soldered to one end of each of the conductor patterns  421   a  and  421   b . Contacts  426  that are connected to a circuit board (PCB) are disposed on the other ends of the respective conductor patterns  421   a  and  421   b . In  FIG. 11 , shielding patterns  421   c  are disposed between the conductor patterns  421   a  and  421   b  to prevent crosstalk. 
     However, the following problems have been encountered in the conventional connector assembly shown in  FIG. 10  and the connector shown in  FIG. 11 . 
     Specifically, in the connector assembly shown in  FIG. 10 , since the female contacts  202  disposed inside the second connector  201  have a structure in which these contacts make receiving contact or elastic contact with the signal conductors  121  (formed on the respective boards  120 ) used as male type contacts during mating, these female contacts are susceptible to damage during mating. Consequently, as insertion and extraction of the first connector  101  and second connector  201  are repeated, there is a high probability that damaged female contacts  202  will be generated. Accordingly, it is desirable that it be easy to replace damaged female contacts  202 . However, to replace damaged female contacts  202 , it is necessary to release the connection of all of the female contacts  202  with the multi-layer board  301 , to remove the second connector  201  from the multi-layer board  301 , and to remove the female contact  202  in question from the housing of the second connector  201 . Accordingly, such replacement is difficult to accomplish. 
     For the connector shown in  FIG. 11 , replacing damaged female contacts  425 , requires that the connection of the contacts  426  connected to the circuit board be released from the circuit board, that the connector  401  be removed from the circuit board, that the board to which the female contact  425  in question is attached be removed from the housing  410 , and that the female contact  425  in question be removed from the board. Again, such replacement is not easily accomplished. 
     SUMMARY OF THE INVENTION 
     The present invention provides a connector assembly which allows the easy replacement of easily damaged female contacts, and which can be used in data transfer systems such as communications devices that transmit data signals at a high speed. The connector assembly comprises a first connector having a plurality of first boards which have conductors formed on the surfaces thereof, a second connector having a plurality of second boards which have conductors formed on the surfaces thereof, and a relay connector which is attached to the first connector or second connector. A plurality of female contacts having first female contact portions that contact the conductors of the first boards and second female contact portions that contact the conductors of the second boards are press-fitted in the relay connector. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a connector assembly according to an exemplary embodiment of the present invention; 
         FIG. 2  is a perspective view of showing the first connector and relay connector from the connector assembly of  FIG. 1 , attached; 
         FIGS. 3(A) and 3(B)  show the attached first connector and relay connector shown in  FIG. 2 , with  FIG. 3(A)  being a front view, and  FIG. 3(B)  being a sectional view along line  3 B— 3 B in  FIG. 3(A) ; 
         FIG. 4  is a perspective view of one of the contacts used in the first connector of  FIG. 2 ; 
         FIG. 5  is a perspective view of one of the female type contacts used in the relay connector of  FIG. 2 ; 
         FIGS. 6(A)  to (D) show the second connector o  FIG. 2 , with  FIG. 6(A)  being a plan view,  FIG. 6(B)  being a sectional view along line  6 B— 6 B in  FIG. 6(A) ,  FIG. 6(C)  being a left-side view, and  FIG. 6(D)  being a right-side view; 
         FIG. 7  is an explanatory diagram illustrating the connection of electrical wires to the second boards in the second connector; 
         FIG. 8  is a perspective view of a conventional connector used in data transfer systems such as communications devices that transmit data signals at a high speed; 
         FIG. 9  is a side view of the connector shown in  FIG. 8 ; 
         FIG. 10  is a perspective view of a conventional example of a connector assembly; and 
         FIG. 11  is a sectional perspective view of a conventional example of a connector. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Next, an exemplary embodiment of the present invention will be described with reference to the figures.  FIG. 1  is an exploded perspective view of a connector assembly according to an exemplary embodiment of the present invention.  FIG. 2  is a perspective view showing a first connector and relay connector of the connector assembly attached.  FIGS. 3(A)  and (B) show the attached first connector and relay connector shown in  FIG. 2 , with  FIG. 3(A)  being a front view, and  FIG. 3(B)  being a sectional view along line  3 B— 3 B in  FIG. 3(A) .  FIG. 4  is a perspective view of one of the contacts used in the first connector.  FIG. 5  is a perspective view of one of the female contacts used in the relay connector.  FIGS. 6(A) to 6(D)  show the second connector, with  FIG. 6(A)  being a plan view,  FIG. 6(B)  being a sectional view along line  6 B— 6 B in  FIG. 6(A) ,  FIG. 6(C)  being a left-side view, and  FIG. 6(D)  being a right-side view.  FIG. 7  is a diagram illustrating the connection of electrical wires to the second boards in the second connector. 
     In  FIG. 1 , the connector assembly is constructed from a first connector A, a second connector B, and a relay connector C. 
     Here, the first connector A comprises an insulating housing  10  and a plurality of first boards  26  that are supported in a row in the housing  10 . 
     The respective first boards  26  have the same function as the boards  120  shown in  FIG. 8 . Each first board  26  is formed substantially in an L shape, having a mounting leg  27  and a mating leg  28 . The mounting leg  27 , which extends in the forward-rearward direction (the left-right direction in  FIG. 1 ), is used for mounting the respective first board  26  on a motherboard (not shown in the figures). The mating leg  28 , which extends downward from the mounting leg  27 , is used for mating with the relay connector C. In an exemplary embodiment, first boards  26  are constructed from an insulating board material such as FR4, with a plurality of signal conductors (not shown in the figures) and a plurality of ground conductors (not shown in the figures) formed on the front and back surfaces of the first boards  26 , such that the ground conductors surround the signal conductors with a specified distance retained between the two types of conductors. The signal conductors are terminated at one end by conductive pads  30  that are disposed on the front end of the mating legs  28 , and at the other end by conductive pads  29  disposed on the lower end of the mounting legs  27 . The ground conductors are terminated by conductive pads  29  disposed on the lower end of the mounting legs  27 . 
     The housing  10  comprises a front housing portion  11  and an accommodating body  17 . The front housing portion  11  comprises a mating portion  12  that extends in the vertical direction, and a top portion  13  that extends rearward from the upper end of the mating portion  12 . The front housing portion  11  may be formed, for example, by molding an insulating resin. A plurality of slits  14  are formed in the mating portion  12  to receive the respective first boards  26 , such that the mating legs  28  of the first boards  26  pass through the plurality of slits  14 . The respective slits  14  extend in the vertical direction of the mating portion  12 , and pass through the mating portion  12  in the forward-rearward direction as shown in  FIG. 3(B) . As is shown in  FIG. 3(B) , when the mating legs  28  of the first boards  26  are passed through the slits  14 , the movement of the mating legs  28  of the first boards  26  in the vertical direction is restricted by the upper and lower walls of the slits  14 , so that the first boards  26  are supported in the front housing portion  11 . The mating legs  28  of the first boards  26  are passed through the slits  14  until the front ends of the mating legs  28  are coplanar with the front end surface of the mating portion  12  of the front part housing  11 . A plurality of first recesses  15  are formed in the respective slits  14 , configured to receive first elastic contact arms  52  of female contacts  50  (described later) when they are inserted into the first recesses  15 . Moreover, a plurality of locking projections  16  are formed on the upper end surface of the mating portion  12 . 
     The accommodating body  17  comprises a platform  18  that extends in the forward-rearward direction, and a vertical rear wall  19  that extends upward from the rear end of the platform  18 . This accommodating body  17  may be formed, for example, by molding an insulating resin. A plurality of grooves  20  are formed in the platform  18 , into which, the lower ends of the mounting legs  27  of the respective first boards  26  are inserted. A plurality of contact holes  20   a  are formed in the bottom parts of the respective grooves  20 , configured to receive contacts  22  for making an electrical connection with the conductive pads  29  of the first boards  26 . A plurality of grooves  21  are formed in the rear wall  19  to receive the rear ends of the mounting legs  27  of the respective first boards  26 . The front housing portion  11  and accommodating body  17  are locked to each other by locking means not shown in the figures. 
     As is shown most clearly in  FIG. 4 , each of the contacts  22  comprises a base  23  which is disposed inside the corresponding contact hole  20   a  of the accommodating body  17 , a pair of elastic contact arms  25  that extend upward from the upper end of the base  23  via shoulders  24 , and a press-fitting portion  26  which extends downward from the base  23 . These contacts  22  may be formed, for example, by stamping metal plates. The contacts  22  are configured such that when the bases  23  are disposed inside the contact holes  20   a , the shoulders  24  are positioned on the bottom of the slits  20 , restricting downward movement. The pair of elastic contact arms  25  receive and contact the conductive pads  29  of the first boards  26 , and the press-fitting portions  26  are press-fitted in the motherboard when the first connector A is mounted on the motherboard. 
     Next, the second connector B will be described. In an exemplary embodiment of the invention, connector B comprises a metal housing  60  and a plurality of second boards  64  that are attached in a row inside the housing  60 . The housing  60  comprises a mating portion  61  which has a recess configured to receive the mating portion  42  of the relay connector C, and a cable lead-out  62 , disposed on the end of the housing  60  opposite from the mating portion  61 . Latch arms  63  are formed on the mating portion  61 . 
     The respective second boards  64  are constructed from an insulating board material such as FR4, and a plurality of signal conductors (not shown in the figures) and a plurality of ground conductors (not shown in the figures) are formed on the front and back surfaces of each second board  64 . The signal conductors are terminated by conductive pads  65  (shown in  FIG. 6B ) at an end of the respective second board  64  configured to mate with the relay connector C. At the opposite end of the signal conductors, they are terminated by conductive pads  66  disposed on substantially the central portions of the second boards  64 . Each of the second boards  64  is attached to the housing  60  so that the relay connector C mating end protrudes into the recess of the mating portion  61  of the housing  60 . 
     As is shown in  FIG. 7 , a core wire  72  of an insulated electrical wire  71  is connected by soldering to each of the conductive pads  66  of each second board  64 . Furthermore, a plurality of cables  70  each bundling a plurality of insulated electrical wires  71  are led out of the second housing B via the cable lead-out  62 . 
     As shown in  FIGS. 1 ,  2 ,  3 A, and  3 B, the relay connector C comprises an insulating housing  40  and a plurality of rows of female contacts  50  that are press-fitted in the housing  40 . 
     The housing  40  comprises a first connector mating portion  41  which has a recess that receives the mating portion  12  of the first connector A, and a second connector mating portion  42  that protrudes forward (to the left in  FIG. 1 ) from the first connector mating portion  41 . The housing  40  may be formed, for example, by molding an insulating resin. Furthermore, locking holes  45  are formed in the upper end surface of the first connector mating portion  41 . The locking projections  16  on the mating portion  12  of the first connector A are locked into these locking holes  45  by insertion of the first connector A into the relay connector C. Moreover, a plurality of slits  43  which receive the mating end of the second boards  64  of the second connector B are formed in the second connector mating portion  42 . Each of the slits  43  extends in the vertical direction of the second connector mating portion  42  as shown in  FIGS. 1 through 3 . A latch arm anchoring hole  46  is formed in the top of the second connector mating portion  42  to anchor one of the latch arms  63  of the second connector B. 
     As is shown in  FIG. 3(B)  and  FIG. 5 , each female contact  50  comprises a press-fitting base  51  which is press-fitted in the bottom wall of the recess in the first connector mating portion  41  of the housing  40 , a pair of first elastic contact arms (first female contact)  52  which extend from the press-fitting base  51  into the interior of the recess in the first connector mating portion  41 , and a pair of second elastic contact arms (second female contact)  53  which extend from the press-fitting base  51  into the interior of a second contact recess  47  formed in the corresponding slit  43  of the second connector mating portion  42 . The female contacts  50  may each be formed, for example, by stamping and forming a metal plate. A plurality of barbs  51   a  are formed in the upper and lower edges of the press-fitting base  51 , and are anchored by press-fitting in the lower wall of the recess of the first connector mating portion  41 . Furthermore, the first elastic contact arms  52  are arranged so that these arms elastically contact the conductive pads  30  in which the signal conductor patterns of the first boards  26  are terminated when the relay connector C is mated with the first connector A. Moreover, the second elastic contact arms  53  are arranged so that these arms elastically contact the conductive pads  65  in which the signal conductor patterns of the second boards  64  are terminated when the second connector B is mated with the relay connector C. 
     As is shown in  FIGS. 2 and 3 , the relay connector C is mated with the first connector A and attached to the first connector A before the second connector B is mated. When the relay connector C and first connector A are to be attached, the mating portion  12  of the first connector A is inserted into the recess of the first connector mating portion  41  of the relay connector C, and the locking projections  16  of the first connector A are locked in the locking holes  45  of the relay connector C. When the relay connector C and first connector A are mated, the first elastic contact arms  52  of the female contacts  50  of the relay connector C elastically contact the conductive pads  30  of the first boards  26 , so that the female contacts  50  are electrically connected with the contacts  22  and motherboard via the signal conductors on the first boards  26 . 
     Next, the second connector B is mated with the relay connector C after the relay connector C has been attached to the first connector A. As a result, the connector assembly is completed. To mate the second connector B and relay connector C, the second connector mating portion  42  of the relay connector C is inserted into the recess of the mating portion  61  of the second connector B, and the latch arms  63  of the second connector B are anchored in the latch arm anchoring holes  46  of the relay connector C. When the second connector B and relay connector C are mated, the conductive pads  65  of the second boards  64  of the second connector B contact the second elastic contact arms  53  of the female contacts  50  of the relay connector C. As a result, the insulated electrical wires  71  are electrically connected with the female contacts  50  of the relay connector C via the signal conductors on the second boards  64 , and are further electrically connected with the contacts  22  and motherboard via the signal conductors on the first boards  26  of the first connector A. 
     In the exemplary connector assembly described above, the conductive pads  30  (in which the signal conductors of the respective first boards  26  are terminated) and the conductive pads  65  (in which the signal conductors of the respective second boards  64  are terminated) are utilized as male contacts, contacting the female contacts  50  of the relay connector C. Furthermore, the conductive pads  29  (in which the signal conductors of the respective first boards  26  are terminated) are connected to the motherboard via the contacts  22 , while the insulated electrical wires  71  are connected by soldering to the conductive pads  66  in which the signal conductors of the respective second boards  64  are terminated. As a result, the impedance of the signal paths inside the connector assembly can be maintained at a uniform value, so that data signals can be transmitted at a high speed. 
     Furthermore, in this connector assembly, the second connector B is mated with the relay connector C in a state in which the relay connector C has already been attached to the first connector A. Accordingly, the second elastic contact arms  53  of the female contacts  50  (disposed in the relay connector C) that are contacted by the conductive pads  65  of the second connector B are easily damaged. In cases where the second elastic contact arms  53  of the female contacts  50  are damaged, or in cases where the first elastic contact arms  52  of the female contacts  50  are damaged, the corresponding female contacts  50  are easily replaced by the following method. 
     First, after the second connector B is removed from the relay connector C, the relay connector C is removed from the first connector A. Then, the corresponding female contact  50  is removed from the housing  40 , and a new female contact  50  is press-fitted into the housing  40 . Then, it is necessary merely to mate the relay connector C with the first connector A, and then to mate the second connector B with the relay connector C. Accordingly, in the connector assembly of the present embodiment, there is no need to remove the relay connector C from the motherboard, etc., when female contacts  50  are replaced, and damaged female contacts  50  can be replaced by the simple method described above. 
     An embodiment of the present invention has been described above. However, the present invention is not limited to this embodiment; various alterations or modifications are possible. 
     For example, the connector assembly is arranged so that the relay connector C is first attached to the first connector A; however, it would also be possible to attach the relay connector C to the second connector B, and then to mate the first connector A with the relay connector C. 
     Furthermore, the first female contacts and second female contacts of the female contact  50  are respectively constructed from elastic contact arms  52  that elastically contact the conductive pads  30  formed on the surfaces of the first boards  26  and elastic contact arms  53  that elastically contact the conductive pads  65  formed on the surfaces of the second boards  64 ; however, it would also be possible to devise these contact parts so that the parts receive the ends of the first boards  26  or second boards  64  and contact the conductive pads  30  or  65  on the surfaces of the boards.