Patent Publication Number: US-7722366-B2

Title: Board-mounted electrical connector

Description:
FIELD OF THE INVENTION 
   This invention generally relates to the art of electrical connectors and, particularly, to an electrical connector for mounting on a circuit board. 
   BACKGROUND OF THE INVENTION 
   Generally, an electrical connector includes some form of dielectric housing which often is molded of plastic material. A plurality of conductive metal terminals are mounted in the housing. In many applications, the connector is designed or adapted for mounting on a printed circuit board, and the terminals have tail portions for connection, as by soldering, to appropriate circuit traces on the board. For instance, the tail portions may be inserted into through holes in the circuit board, with the tail portions connected to circuit traces on the board and/or in the holes. 
   One application for such board mounted connectors is in the automotive industry for computer control of various functions of the automobile by connecting a multi-function electrical cable to a circuit board. For example, a computer control device for an automobile is contained in a control box and is placed under seat, behind a dashboard, in the engine compartment, etc. Due to the number of system functions, a connector for connecting the multi-function cable to the circuit board has undergone an increase in the number of terminals of the connector, along with hybridization of the types of terminals as well as various different terminal sizes. 
   Conventionally, a connector of this type generally includes a plurality of rows of terminals arranged in parallel, with the terminals being soldered to the circuit traces on the board. However, with different sizes and types of terminals, the soldering device and soldering process has become quite complicated, resulting in an increase in labor and costs. 
   Consequently, it has been proposed to press-fit the terminals of the connector into through holes in the circuit board, rather than using solder connections. An example is shown in  FIGS. 31-35  and as disclosed in JP 09-501435 A, Official Gazette of Japanese Utility Model Registration No. 2113212, and JP 3244440 B. 
   Specifically, a connector, generally designated  10 , is adapted for mounting on a circuit board, generally designated  12 , having through holes  12   a  and circuit traces  12   b  extending into the holes. The connector includes a dielectric housing  14  mounting a plurality of L-shaped terminals, generally designated  16 . The terminals have downwardly-directed tails  16   a  with press-fit portions  16   b  at the distal ends thereof, along with locking portions  16   c  immediately upwardly of the press-fit portions. The press-fit portions  16   b  of tails  16   a  of terminals  16  are inserted through holes  12   a  of circuit board  12  in the direction of arrow “A” ( FIG. 31 ). The terminals are arranged in four horizontal rows as well as a plurality of vertical columns as seen in  FIG. 33 .  FIG. 32  shows four terminals in a single column. 
   A press-fitting block, generally designated  18 , is used to insert the terminals into the holes in the circuit board. The block includes a plurality of slots  18   a  which are aligned with the plurality of columns of terminals. A plurality of windows  18   b  communicate with the slots. As best seen in  FIG. 33 , a plurality of locking grooves  18   c  are formed at the bottom of the press-fitting block generally at the entrances to slots  18   a . The locking grooves are sized for receiving locking portions  16   c  of the terminals in a locking, abutting engagement therewith. 
   In order to electrically mount connector  10  on circuit board  12 , the connector is positioned as shown in  FIGS. 32 and 33  with the extreme distal ends of tails  16   a  of the terminals inserted holes  12   a  in the circuit board. It can be seen that press-fit portions  16   b  of the terminals have enlarged compliant configurations so that the press-fit portions cannot be inserted into the holes without pressure. Press-fitting block  18  then is positioned as shown in  FIG. 32  and is pushed downwardly in the direction of arrow “B”. Locking portions  16   c  of the terminals lockingly engage within locking grooves  18   c  of the block, whereupon the block presses the press-fit portions  16   b  of the terminals into holes  12   a  in the circuit board as seen in  FIG. 34 . The enlarged compliant press-fit portions  16   b  of the terminals are compressed and establish a tight electrical connection with the circuit traces in the through holes in the circuit board. 
   The above-described prior art apparatus or system works adequately when the terminals are arranged in parallel at the same pitch, and the terminals are generally of the same configurations. However, if the terminals are at different pitches (spacings) the use of a single press-fitting block  18  becomes quite complicated. 
   For instance,  FIG. 35  shows connector  10  in conjunction with press-fitting block  18  and wherein first terminals  16 A are in one row and second terminals  16 B are in a second row offset from the first row. It can be seen that the locking portions  16   c  of the terminals also are offset. In order to use a single press-fitting block  18 , slots  18 A and  18 B also must be offset from each other which requires locking grooves  18   c  also to be offset. Unfortunately, the locking grooves interfere with each other or become parts of each other and cannot fulfill their intended purposes. This problem is magnified by increasing the number of terminals which decreases the pitch or spacing between the terminals, as well as in connectors where different pitches for different rows of terminals are encountered, along with different configurations of terminals. The present invention is directed to solving this myriad of problems. 
   SUMMARY OF THE INVENTION 
   An object, therefore, of the invention is to provide a new and improved electrical connector of the character described, for mounting on a circuit board. 
   In the exemplary embodiment of the invention, the connector includes a dielectric housing mounting a plurality of first terminals having circuit board press-fit portions projecting therefrom. A plurality of second terminals are mounted on the housing and have circuit board press-fit portions projecting therefrom. A press-fitting block is engageable with the housing and is locked to the press-fit portions of the first terminals for press-fitting the first terminals into holes in the circuit board. The press-fit portions of the second terminals are exposed exteriorly of the housing and the press-fitting block for locking engagement by an appropriate independent press-fitting jig for press-fitting the second terminals into holes in the circuit board. 
   According to one aspect of the invention, the press-fitting block has an abutment surface arranged for engagement by an abutment surface on the press-fitting jig. Therefore, the jig is effective to press fit the first terminals into the circuit board, through the press-fitting block, as the jig is press-fitting the second terminals into the board. 
   According to another aspect of the invention, the first and second terminals have lock portions engageable by the press-fitting block and the press-fitting jig, respectively. The lock portions are adjacent to the press-fit portions of the respective terminals. 
   As disclosed herein, the first terminals are signal terminals and the second terminals are power source terminals. The first and second terminals may be arranged in parallel at different pitches. The first and second terminals may be arranged in generally parallel rows. The first terminals may be offset from the second terminals in a direction generally parallel to the rows. In the exemplary embodiment, the first and second terminals are L-shaped, with mounting legs mounted in the housing and generally right-angled legs including the press-fit portions. 
   Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the figures and in which: 
       FIG. 1  is a perspective view of an electrical connector according to the invention, mounted on a circuit board; 
       FIG. 2  is a perspective view of the dielectric housing of the connector; 
       FIG. 3  is a fragmented perspective view taken in the direction of arrow “A” in  FIG. 1 ; 
       FIG. 4  is a fragmented, enlarged perspective view looking the direction of arrow “B” in  FIG. 2 ; 
       FIG. 5  is a plan view of four terminals in one column in the connector of the invention, before the terminals are formed in right-angles; 
       FIG. 6  is a perspective view of one of the press-fitting blocks; 
       FIG. 7  is a perspective view looking in the direction of arrow “C” in  FIG. 6 ; 
       FIG. 8  is a vertical section taken generally along line D-D in  FIG. 6 ; 
       FIG. 9  is an enlarged, fragmented perspective view looking into the slots and locking grooves in one of the press-fitting blocks; 
       FIG. 10  is a further enlarged depiction of one of the slots and associated locking groove, in the direction of arrow “E” in  FIG. 8 ; 
       FIG. 11  is a fragmented perspective view showing how one row of the signal terminals are mounted in the housing; 
       FIG. 12  is a view similar to that of  FIG. 11 , with the terminals bent to their right-angled configurations; 
       FIGS. 13 and 14  are views similar to that of  FIGS. 11 and 12 , respectively, but of a second row of signal terminals; 
       FIGS. 15 and 16  are views similar to that of  FIGS. 11 and 12  but showing a third row of signal terminals; 
       FIG. 17  is a vertical section taken generally along line  17 - 17  in  FIG. 16 ; 
       FIG. 18  is a bottom perspective view showing a pair of the press-fitting blocks being mounted in the direction of arrow “F” onto the signal terminals; 
       FIG. 19  is a top perspective view similar to  FIG. 18 ; 
       FIG. 20  is an enlarged, fragmented section through one of the slots and locking grooves in one of the press-fitting blocks in conjunction with one of the terminals; 
       FIG. 21  is a perspective view showing the power terminals added to the connector; 
       FIG. 22  is a somewhat schematic layout of the signal and power terminals as if taken in the direction of line  22 - 22  in  FIG. 21 ; 
       FIG. 23  is a side elevational view as looking at the right-hand side of  FIG. 21 ; 
       FIG. 24  is a bottom perspective view showing a press-fitting jig being moved in the direction of arrow “G” into engagement with the power terminals; 
       FIG. 25  is a perspective view of the press-fitting jig; 
       FIG. 26  is an enlarged section taken generally along line  26 - 26  in  FIG. 25 ; 
       FIG. 27  is a fragmented section taken generally along line  27 - 27  in  FIG. 26 ; 
       FIG. 28  is a side elevational view looking at the side of  FIG. 24 , with the press-fitting jig moved into engagement with the press-fitting blocks, in conjunction with a circuit board; 
       FIG. 29  is an enlarged, fragmented section showing one of the terminals fully inserted into the circuit board; 
       FIG. 30  is a perspective view of the condition of the connector including the press-fitting blocks as well as the press-fitting jig having press-fit all of the terminals into the circuit board; 
       FIG. 31  is an exploded perspective view of the prior art as described in the Background, above; 
       FIG. 32  is a vertical section through the prior art connector; 
       FIG. 33  is a vertical section taken generally along line  33 - 33  in  FIG. 32 ; 
       FIG. 34  is a view similar to that of  FIG. 33  and showing the terminals fully inserted the circuit board; and 
       FIG. 35  is a diagram of the offset slots as described in the Background, above. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to the drawings in greater detail, and first to  FIG. 1 , the invention is embodied in an electrical connector, generally designated  36 , which is designed or adapted for mounting on a circuit board  38 . The connector includes a dielectric housing, generally designated  40 , having a mounting face  40   a  into which three rows of signal terminals, generally designated  42 ,  44  and  46 , are mounted, along with one row of power source terminals, generally designated  48 . The signal terminals are arranged in a first pitch along the rows, and the power source terminals are arranged in a second pitch along the single row thereof. As will be understood hereinafter, a plurality of press-fitting blocks, generally designated  50 , are used to press-fit signal terminals  42 - 46  into circuit board  38 . 
   Referring to  FIG. 2  in conjunction with  FIG. 1 , housing  40  includes a plurality of vertical columns  40   b  projecting-rearwardly from mounting face  40   a  of the housing. The housing may be molded of dielectric plastic material, and the columns may be molded integrally therewith. 
     FIG. 3  shows that housing  40  has one or more receptacles  40   c  for receiving one or more complementarily mating connectors (not shown). In the illustrated embodiment, a plurality of receptacles  40   c  are provided for receiving a plurality of mating connectors, with the receptacles divided by interior walls or partitions  40   d  of the housing. 
     FIG. 4  shows a plurality of terminal-receiving passages through mounting face  40   a  of housing  40 . There are three rows of passages  52 X,  52 Y and  52 Z for receiving signal terminals  42 ,  44  and  46 , respectively. There is one row of passages  54  for power source terminals  48 . The passages for the signal terminals are arranged in columns  56  which do not necessarily line up with or intersect passages  54  for the power source terminals. Specifically, the passages for the signal terminals in each row thereof are on a first, smaller pitch or spacing □P 1 ″, and the passages in the row thereof for the power source terminals are at a larger pitch or spacing □P 2 ″. The end result is that the passages for the signal terminals often are offset from the passages for the power source terminals.  FIG. 4  also shows a support platform  58  which may be positioned at various points along housing  40  (see  FIG. 2 ) for supporting the press-fitting blocks  50 . 
   Referring to  FIG. 5 , all of the signal and power source terminals are stamped and formed of conductive sheet metal material. The terminals are shown in  FIG. 5  in their stamped condition for insertion into housing  40 , before the terminals are bent into their final right-angled configurations for insertion into circuit board  38 . Specifically, all of the signal and power source terminals  42 - 48  have enlarged mounting sections  60  for fixing the terminals in the housing. The distal ends of all of the terminals have enlarged press-fit portions  62 . All of the terminals have lock portions  64  immediately adjacent the press-fit portions, for purposes described hereinafter. It can be seen that signal terminals  42  are shorter than signal terminals  44  which, in turn, are shorter than signal terminals  46  which, in turn, are shorter than power source terminals  48 . This allows the terminals to be bent at right angles and nested in vertical relationships as will be seen hereinafter. Also as will be seen hereinafter, press-fit portions  62  of the terminals are slightly larger than their through holes in circuit board  38 , and lock portions  64  are larger than the respective through holes to limit the insertion of the terminals into the holes. 
     FIGS. 6-8  show one of the press-fitting blocks  50  shown in and described above in relation to  FIG. 1 . Each press-fitting block is wide enough to receive the nested signal terminals  42 - 46  in their L-shaped configurations as described hereinafter.  FIG. 1  shows five blocks along the length of housing  40  of connector  36 . The blocks may be molded of dielectric plastic material. 
   Each press-fitting block  50  includes a plurality of slots  66  which are open at the inside thereof, as at  66   a , and at the bottom thereof, as at  60   b . Therefore, slots  66  are open toward mounting face  40   a  of the housing and are open toward the circuit board. When the block is slidably mounted to the housing, slots  66  are aligned with columns  56  (see  FIG. 4 ) of passages  52 X- 52 Z for receiving three signal terminals in each slot. Correspondingly, as best seen in  FIG. 8 , three locking grooves  68  are formed at opposite sides of each slot  66  along bottom opening  66   b  of the slot. A plurality of through passages  70  are formed through the block for receiving the power source terminals, as will be seen hereinafter. 
     FIGS. 9 and 10  show enlarged depictions of the signal terminal-receiving slots  66  and locking grooves  68  in each press-fitting block  50 . It can be seen that the locking grooves are located at opposite sides of the slots. The bottom edges of locking grooves  68  are beveled or chamfered, as seen at  68   a  in  FIG. 10 . 
     FIGS. 11-16  show the method of mounting signal terminals  42 ,  44  and  46  into housing  40 .  FIG. 7  shows the first row of signal terminals  42  inserted into passages  52 X in their linear condition as described above in relation to  FIG. 5 . Once inserted, the terminals are bent to their right-angled configurations as shown in  FIG. 12 , in condition for insertion into circuit board  38 . 
   After the first row of signal terminals  42  are inserted into the housing and are bent into their right-angled configurations, the second row of signal terminals  44  are inserted into the housing and are bent as shown in  FIGS. 13 and 14 . The second row of signal terminals are inserted into passages  52 Y. 
   After the second row of signal terminals  44  are inserted into the housing and are bent into their right-angled configurations, the third row of signal terminals  46  are inserted into the housing and are bent as shown in  FIGS. 15 and 16 . The third row of signal terminals are inserted into passages  52 Z. 
     FIG. 17  shows how the three rows of signal terminals  42 ,  44  and  46  are in a nested, columnar arrangement. This depiction also clearly shows the right-angled configurations of the nested signal terminals. 
   After all of the signal terminals are inserted into housing  40  and are bent into their right-angled configurations, as described above in relation to  FIGS. 11-17 , the press-fitting blocks  50  are installed over the signal terminals as shown in  FIGS. 18 and 19 . The blocks are guided by columns  40   b  and are positioned in abutting arrangement against mounting face  40   a  of housing  40  and the blocks are moved downwardly in the direction of arrow □F□ ( FIG. 18 ) to an abutting position on housing  40  as shown in  FIG. 19 . In this position,  FIG. 20  shows how one of the signal terminals  42  is locked in one of the slots  66  in one of the blocks  50 . It can be seen that locking portion  64  of the terminal is locked within the locking groove  68  at the bottom of the slot. The press-fit portion  62  of the terminal projects below the block. 
   After the press-fitting blocks  50  are installed as described above in relation to  FIGS. 18-21 , power source terminals  48  are inserted through passages  70  in the blocks and into passages  54  in housing  40 . After being inserted in their linear configurations as shown in  FIG. 5 , the power source terminals are bent into right-angled configurations as shown in  FIG. 21 . 
     FIG. 22  shows a schematic layout of the signal and power source terminals. As stated, the signal terminals are arranged in three rows  70 . The signal terminals also are arranged in columns  56  as described above in relation to  FIG. 4 . The signal terminals are spaced in each row on pitch “P 1 ”. 
   As described above in relation to  FIG. 4 ,  FIG. 22  shows that power source terminals  48  are on a different, larger pitch “P 2 ”. Consequently, the power source terminals often are irregularly offset from the signal terminals. Still further, it can be seen that the power source terminals are larger than the signal terminals. All of these variances in the pitch, alignment, size and other differences between the terminals make it extremely difficult if at all possible to mold a press-fitting block which can press all of the terminals into the circuit board. 
   After press-fitting blocks  50  are installed over the signal terminals, and the power source terminals are mounted through the blocks into the housing, this entire connector assembly is preliminarily mounted to circuit board  38  as seen in  FIG. 23 . Specifically, the tips of the signal and power source terminals are inserted into through holes  78  in the board, but the press-fit portions  62  of the terminals cannot enter the holes and engage the edges of the holes at the top surface of the board. 
     FIG. 24  shows a press-fitting jig, generally designated  80 , which is used not only to press the power source terminals  48  into the printed circuit board, but to force the entire connector, including press-fitting blocks  50  and the signal terminals, into the respective holes in circuit board  38 . 
   In particular, referring to  FIGS. 25-27  in conjunction with  FIG. 24 , press-fitting jig  80  is generally L-shaped in cross-section as seen in  FIG. 26 . The jig includes a plurality of slots  82  for receiving or positioning over the exposed tail portions of the power source terminals. Locking grooves  84  are formed at the bottoms of slots  82 . With the L-shaped configuration of the jig, slots  82  are formed in a vertical leg  86  of the jig, and a horizontal leg  88  of the jig extends over the top of the press-fitting blocks  50  as can be seen in  FIG. 24 . The jig extends the entire length of the connector over all five blocks  50 . 
     FIG. 28  shows press-fitting jig  80  positioned over power source terminals  48  and onto the top of press-fitting blocks  50 , with connector  36  in the condition shown in  FIG. 23  and described above, preliminarily mounted on circuit board  38 . To completely assemble the connector to the board and to press-fit all of the signal terminals  42 - 46  and the power source terminals  48  into the circuit board, the jig is forced downwardly in the direction of arrows “G” ( FIG. 28 ). This force is transmitted to the press-fitting blocks  50  in the direction of arrow “H” as a bottom surface  90  of the jig engages top surfaces  92  of the blocks. As the jig is forced downwardly, the entire connector, including press-fitting blocks  50 , are completely mounted to circuit board  38  as seen in  FIG. 30 , with all of the signal terminals  42 - 46  and the power source terminals  48  inserted into their respective through holes in the circuit board. 
   Finally,  FIG. 29  shows one of the terminals which could be any of the signal or power source terminals inserted into a respective through hole  78  in circuit board  38 . It can be seen that press-fitting portion  62  has been compressed from its rounded configuration shown in  FIG. 5  to a compressed condition shown by full lines in  FIG. 29 . This rigidly fixes the terminal in the through hole in the board. Locking portion  64  of the terminal abuts against a top surface  94  of the circuit board. 
   It can be understood that the invention allows the press-fitting blocks  50  and the press-fitting jig  80  to be fabricated in extremely simple configurations. Yet, the signal terminals and the power source terminals can be at different pitches, different sizes and offset from each other. The versatility of the inventive system herein is extremely valuable. 
   It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.