Abstract:
A printed circuit board includes a surface and having first and second adjacent apertures. First and second electrical terminals include respective ends disposed in the first and second apertures of the printed circuit board, respective shoulders adjacent to the ends of the first and second electrical terminals and engaged with the surface of the printed circuit board, and respective insertion tabs adjacent to the shoulders of the first and second electrical terminals and located respective first and second distances away from the surface of the printed circuit board. The first and second distances are different such that the first and second insertion tabs do not touch one another.

Description:
BACKGROUND 
     This invention relates in general to printed circuit board (PCB) assemblies having a PCB and electrical terminals attached thereto. In particular, this invention relates to an improved electrical terminal for such a PCB assembly that facilitates more efficient and effective placement of a plurality of the improved electrical terminals on the PCB. 
     Such PCB assemblies may be found in a variety of applications, such as power-distribution systems or junction boxes that are used to manage power distribution in automotive vehicles. Junction boxes typically include housings and a printed circuit board with electrical terminals, fuses, relays, circuit breakers, and other electrical devices mounted thereto. Electrical devices, such as connectors and wiring harnesses, may be connected to the terminals through the housings. 
     The electrical terminals may include terminal blades, forked female terminals, and/or portions having any other desired shape, and combinations thereof, that extend from one or both surfaces of the PCB. 
     The terminals may include insertion tabs that extend substantially transversely from the terminal. Each insertion tab provides an engagement surface against which an insertion tool may engage and urge the terminal through an aperture in the PCB, thereby mounting the terminal to the PCB. The insertion tabs are typically flat and in the same plane as a body of the terminal. 
     A plurality of terminals may be mounted in line on the PCB such that the terminals are substantially co-planar. When adjacent terminals are mounted to the PCB in this manner, the insertion tabs may also be co-planar. Adjacent terminals are typically mounted with a minimum distance therebetween to ensure that the adjacent electronically conductive terminals do not touch each other and/or to provide space for a wall of a housing that may be mounted about each terminal. A minimum center line distance between adjacent terminals is thus determined by the size of the insertion tabs that extend substantially transversely from, and in the same plane as, the body of the terminal. 
     End users of conventional junction boxes however, may desire a reduced package size for the junction box, thus requiring smaller PCB assemblies within the smaller junction box. It is therefore desirable to provide a terminal design that allows adjacent terminals to be mounted closer together, thus reducing the center line distance between adjacent terminals and allowing the size of the PCB assembly and the package size of the junction box to be reduced. 
     SUMMARY OF THE INVENTION 
     This invention relates to an improved PCB assembly that allows adjacent terminals mounted to the PCB to be mounted closer together than is possible in conventional PCB assemblies. One embodiment of the PCB assembly includes a PCB and first and second electrical terminals mounted thereto. The first electrical terminal comprises a body having a first end and a second end, a mounting member extending outwardly from the first end configured for insertion into an aperture formed in the PCB, shoulders defined adjacent the mounting member, and a first insertion tab extending outwardly from the body at the first end thereof. The second electrical terminal is mounted adjacent the first electrical terminal and comprises a body having a first end and a second end, a mounting member extending outwardly from the first end configured for insertion into an aperture formed in the PCB, shoulders defined adjacent the mounting member, and a second insertion tab extending outwardly from the body at the first end thereof. The first insertion tab and the second insertion tab are axially spaced apart. 
     Various advantages of the invention will become apparent to those skilled in the art from the following detailed description, when read in view of the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross sectional side elevational view of a portion of a known PCB assembly. 
         FIG. 2  is a cross sectional side elevational view of a portion of an improved PCB assembly according to the invention shown subsequent to a first step of a first embodiment of a method assembling the improved PCB assembly. 
         FIG. 3  is a cross sectional side elevational view of a portion of the improved PCB assembly illustrated in  FIG. 2  shown subsequent to a second step of the first embodiment of a method of assembling the improved PCB assembly. 
         FIG. 4  is a perspective view of a first embodiment of an electrical terminal illustrated in  FIG. 3 . 
         FIG. 5  is a side elevational view of a second embodiment of an electrical terminal illustrated in  FIGS. 2 and 3 . 
         FIG. 6  is a side elevational view of a third embodiment of an electrical terminal illustrated in  FIG. 3 . 
         FIG. 7  is a side elevational view of a fourth embodiment of an electrical terminal illustrated in  FIGS. 2 and 3 . 
         FIG. 8  is a side elevational view of a fifth embodiment of an electrical terminal illustrated in  FIG. 3 . 
         FIG. 9  is a side elevational view of a sixth embodiment of an electrical terminal illustrated in  FIGS. 2 and 3 . 
     
    
    
     DETAILED DESCRIPTION 
     The present invention will now be described with occasional reference to the specific embodiments of the invention. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. 
     Referring now to  FIG. 1 , there is illustrated a portion of a conventional PCB assembly  10 . The PCB assembly  10  illustrated in  FIG. 1  includes a PCB  12  having a first major surface  12   a  (upper surface when viewing  FIG. 1 ), a second major surface  12   b  (lower surface when viewing  FIG. 1 ), and a plurality of tuning fork type electrical terminals  14 . The terminals  14  are inserted in respective terminal apertures  12   c  formed through the PCB  12 . 
     As shown in  FIG. 1 , each terminal  14  has a body  16  including a first end  16   a  and a second end  16   b . The first end  16   a  has a mounting post  18  extending therefrom and defines shoulders  20  adjacent the mounting post  18 . The mounting post  18  is configured for insertion and mounting within the apertures  12   c  of the PCB  12 , and the shoulders  20  are configured to engage the second major surface  12   b  of the PCB  12 . 
     The second end  16   b  is configured as a tuning fork type female terminal and includes two substantially parallel prongs  22  defining a slot  23  therebetween for receiving an electrical engagement feature, such as a terminal blade, of another electrical device (not shown). Connection protrusions or members  22   a  extend inwardly (into the slot  23 ) from the prongs  22  and are configured to provide an improved frictional fit of the terminal blade or other electrical engagement feature received in the slot  23 . 
     Insertion tabs  24  extend outwardly from the terminal body  16  between the shoulders  20  and the tuning fork type female terminal  16   b  and are spaced a distance apart from the shoulders  20 . In a known manner, the insertion tabs  24  extend substantially transversely from, and in the same plane as, the terminal body  16 . 
     As shown in  FIG. 1 , the terminals  14  are identical. As a result, when they are mounted to the PCB  12 , the insertions tabs  24  of adjacent terminals  14  are co-planar and aligned linearly along a line L 1 . Accordingly, a minimum centerline distance CL 1  between adjacent terminals  14  is limited by the proximity of adjacent insertion tabs  24  to one another. For example, in the embodiment illustrated in  FIG. 1 , each of the terminals  14  has a width W 1 , measured from outside surfaces of the insertion tabs  24 , of about 5.0 mm to about 5.2 mm. When mounted in a conventional manner as shown, the centerlines of adjacent terminals  14  are spaced apart by a distance CL 1  of between about 6.5 mm and about 6.7 mm. 
     Referring now to  FIGS. 4 through 9 , there are illustrated alternative embodiments of electrical terminals, described in detail below, suitable for use in an improved PCB assembly  90 , shown in  FIGS. 2 and 3 . 
     Referring to  FIG. 4 , a first embodiment of an electrical terminal is shown at  30 . The electrical terminal  30  includes a mounting member or first end  30   a  and a first embodiment of a second end  30   b . The first end  30   a  is configured as a blade. The illustrated blade  30   a  has a width W 2  between about 2.4 mm and about 2.6 mm. 
     The second end  30   b  is configured as a tuning fork type female terminal, similar to the tuning fork type female terminal  16   b  described above. The tuning fork type female terminal  30   b  includes two substantially parallel prongs  32  defining a slot  33  therebetween for receiving an electrical engagement feature, such as a terminal blade, of another electrical device (not shown). Connection protrusions or members  32   a  extend inwardly (into the slot  33 ) from the prongs  32  and are configured to provide an improved frictional fit of the terminal blade or other electrical engagement feature received in the slot  33 . 
     Shoulders  34  are defined at an interface of the blade  30   a  and the tuning fork type female terminal  30   b . The blade  30   a  is configured for insertion through the apertures  12   c  of the PCB  12 , and the shoulders  34  are configured to engage the second major surface  12   b  of the PCB  12 , as shown in  FIG. 3  and described in detail below. 
     A mounting portion  36  may be formed at a proximal end of the blade  30   a  adjacent the second end  30   b . As best shown in  FIG. 3 , the mounting portion  36  has a width W 3  larger than the width W 2  of the blade  30   a . The illustrated mounting portion  36  has a width W 3  between about 3.4 mm and about 3.6 mm. The mounting portion  36  is configured for insertion and mounting within the apertures  12   c  of the PCB  12 . Alternatively, the terminal  30  may be formed without the mounting portion  36 , if desired. 
     Insertion tabs  38  extend outwardly from the tuning fork type female terminal  30  between the shoulders  34  and the prongs  32 , and include a first surface  38   a  and a second or tool-engagement surface  38   b . The insertion tabs  38  are spaced a distance apart from the shoulders  34 . In the embodiment illustrated, the first surface  38   a  is spaced between about 2.3 mm and about 2.5 mm from the shoulders  34 . The electrical terminal  30  has the width W 1 , measured from outside surfaces of the insertion tabs  38  of about 5.0 mm to about 5.2 mm, as shown in  FIG. 3 . 
     A portion  37  of the tuning fork type female terminal  30   b  between the insertion tabs  38  and the shoulders  34  has a width W 6  between about 3.9 mm and about 4.1 mm, as also shown in  FIG. 3 . 
     The dimensions of the electrical terminal  30 , including the blade  30   a  and the tuning fork type female terminal  30   b  described above are not limited to the dimensions disclosed and may have any other desired dimensions. 
     Referring to  FIG. 5 , a second embodiment of an electrical terminal is shown at  40 . The electrical terminal  40  is similar to the electrical terminal  30  and includes the first end  30   a  configured as the blade and a second embodiment of the second end  40   b.    
     The second end  40   b  is configured as a tuning fork type female terminal, and includes the two substantially parallel prongs  32  defining the slot  33  therebetween. The connection protrusions or members  32   a  extend inwardly (into the slot  33 ) from the prongs  32 . 
     In the tuning fork type female terminal  40   b , insertion tabs  42  are provided that are substantially identical to the insertion tabs  38 , including a first surface  42   a  and a second or tool-engagement surface  42   b , but extending outwardly from the tuning fork type female terminal  40   b  at the interface of the blade  30   a  and the tuning fork type female terminal  40   b . Thus, the first surfaces  42   a  of the insertion tabs  42  define shoulders  44 . 
     The electrical terminal  40  has the width W 1  measured from the outside surfaces of the insertion tabs  42 , of about 5.0 mm to about 5.2 mm, as shown in  FIG. 5 . 
     The mounting portion  36  is formed between the blade  30   a  and the first surface  42   a  of the insertion tabs  42 . As described above, the mounting portion  36  has a width W 3  larger than the width W 2  of the blade  30   a.    
     The dimensions of the electrical terminal  40 , including the blade  30   a  and the tuning fork type female terminal  40   b  described above, are not limited to the dimensions disclosed and may have any other desired dimensions. 
     Referring to  FIG. 6 , a third embodiment of an electrical terminal is shown at  50 . The electrical terminal  50  is similar to the electrical terminal  30  and includes a first end configured as a blade  50   a  and a third embodiment of the second end  50   b . The illustrated blade  50   a  has a width W 4  between about 1.1 mm and about 1.3 mm. 
     The third embodiment of the second end  50   b  is configured as a tuning fork type female terminal, and is substantially similar to the first embodiment of the tuning fork type female terminal  30   b , except that a portion  51  of the tuning fork type female terminal  50   b  between the insertion tabs  38  and the shoulders  34  has a width W 7  between about 2.9 mm and about 3.1 mm. The tuning fork type female terminal  50   b  includes the two substantially parallel prongs  32  defining the slot  33  therebetween and the connection members  32   a , as described in detail above. 
     The electrical terminal  50  also includes a mounting portion  52  formed between the blade  50   a  and the tuning fork type female terminal  50   b . The mounting portion  52  has a width W 5  larger than the width W 4  of the blade  50   a . The illustrated mounting portion  52  has a width W 5  between about 2.2 mm and about 2.4 mm, and is configured for insertion and mounting within the apertures  12   c  of the PCB  12 . 
     The insertion tabs  38  extend outwardly from the tuning fork type female terminal  50   b  between the shoulders  34  and the prongs  32  and include the first surface  38   a  and the second or tool-engagement surface  38   b . In the embodiment illustrated, the first surface  38   a  is spaced between about 2.3 mm and about 2.5 mm from the shoulders  34 . The electrical terminal  50  has the width W 1 , measured from outside surfaces of the insertion tabs  38 , of about 5.0 mm to about 5.2 mm. 
     The dimensions of the electrical terminal  50 , including the blade  50   a  and the tuning fork type female terminal  50   b  described above, are not limited to the dimensions disclosed and may have any other desired dimensions. 
     Referring to  FIG. 7 , a fourth embodiment of an electrical terminal is shown at  60 . The electrical terminal  60  is similar to the electrical terminal  50  and includes the first end configured as the blade  50   a  having the width W 4 , the mounting portion  52  having the width W 5 , the tuning fork type female terminal  40   b , and the insertion tabs  42 . 
     The tuning fork type female terminal  40   b  includes the two substantially parallel prongs  32  defining the slot  33  therebetween. Each prong  32  includes the connection protrusion or member  32   a . The insertion tabs  42  include the first surface  42   a  and the second or tool-engagement surface  42   b , wherein the first surfaces  42   a  define the shoulders  44 . 
     Referring to  FIG. 8 , a fifth embodiment of an electrical terminal is shown at  70 . The electrical terminal  70  includes a body  71  having a first end  71   a  and a second end  71   b . The first end  71   a  has a mounting post  73  extending therefrom and defines the shoulders  34  adjacent the mounting post  73 . The body  71  is similar to the second end  30   b  and includes the two substantially parallel prongs  32  defining the slot  33  therebetween. Each prong  32  includes the connection protrusion or member  32   a . The body  71  further includes the insertion tabs  38  extending outwardly from the body  71  between the shoulders  34  and the prongs  32 . Each insertion tabs  38  includes the first surface  38   a  and the second or tool-engagement surface  38   b . The insertion tabs  38  are spaced a distance apart from the shoulders  34 . In the embodiment illustrated, the first surface  38   a  is spaced between about 2.3 mm and about 2.5 mm from the shoulders  34 . 
     Referring to  FIG. 9 , a sixth embodiment of an electrical terminal is shown at  80 . The electrical terminal  80  includes a body  81  having first end  81   a  and a second end  81   b . The first end  81   a  has a mounting post  83  extending therefrom. The body  81  is similar to the second end  40   b  and includes the two substantially parallel prongs  32  defining the slot  33  therebetween. Each prong  32  includes the connection protrusion or member  32   a . The body  81  further includes the insertion tabs  42  extending outwardly from the body  81  at the first end  81   a  thereof and include the first surface  42   a  and the second or tool-engagement surface  42   b , wherein the first surface  42   a  of the insertion tabs  42  defines the shoulders  44 . 
     The dimensions of the electrical terminals  70  and  80 , including the component parts thereof, described above are not limited to the dimensions disclosed, and may have any other desired dimensions. 
     The illustrated mounting post  83  has a tapered distal end. It will be understood that the terminals  70  and  80  may have the mounting post  73 , as shown in  FIG. 8 , or the tapered mounting post  83 , as shown in  FIG. 9 . 
     As described above, the electrical terminals  40 ,  60 , and  80  are similar in that the insertion tabs  42  define the shoulders  44 . Similarly, the electrical terminals  30 ,  50 , and  70  are similar in that the insertion tabs  38  are equidistant from the shoulders  34 , and therefore equidistant from the second major surface  12   b  of the PCB  12 . 
     It will be understood that the insertion tabs  42  on the electrical terminals  40 ,  60 , and the insertion tabs  38  on the electrical terminals  30 ,  50 , and  70  may be formed at any desired axial location, such that when assembled in a PCB assembly, such as shown at  90  in  FIG. 3 , each insertion tab  38  may be axially spaced apart from an adjacent insertion tab  42  a distance D 1  for reasons described below. In the illustrated embodiment, the distance D 1  is about 0.5 mm. Alternatively, the distance D 1  may be any desired distance, including a distance less than about 0.5 mm and a distance greater than about 0.5 mm. 
     Referring now to  FIGS. 2 and 3 , there is illustrated at  90  an improved PCB assembly shown during first and second steps, respectively, of a method of assembling the improved PCB assembly  90  in accordance with the invention. 
     As shown in  FIG. 2 , an insertion tool  92  includes a body  94  having a cavity  94   a , which is configured to receive the tuning fork type female terminal  40   b , and a terminal-engagement surfaces  94   b . The tool  92  is disposed about the tuning fork type female terminal  40   b  of the terminal  40  such that the terminal-engagement surfaces  94   b  engage the tool-engagement surfaces  42   b  of the insertion tabs  42 . A force is applied to the tool  92  in the direction of the arrow A, urging the blade  30   a  into the aperture  12   c  until the shoulders  44  engage, and are seated against, the second major surface  12   b , thereby mounting the terminal  40  to the PCB  12 . Solder (not shown) may then be applied to the terminal  40  on one or both of the first and second major surfaces  12   a  and  12   b , respectively, to provide an electrical connection therebetween. 
     In  FIG. 2 , the terminals  60  and  80  are shown subsequent to being assembled in the same manner as the terminal  40 . Although the tool-engagement surface  42   b  of the terminal  40  is shown as the second surface of the insertion tabs  42 , the terminals  40 ,  60 , and  80  may be configured such that the tool-engagement surface  42   b  is defined on any desired portion of the terminals  40 ,  60 , and  80 . Similarly, the tool  92  may be configured such that the terminal-engagement surfaces  94   b  are defined on any desired portion of the tool  92  that engage the terminals  40 ,  60 , and  80  and allow the terminals  40 ,  60 , and  80  to be urged through the apertures  12   c  and into contact with the second major surface  12   b  of the PCB  12 . Each terminal  60  and  80  may also be mounted to the PCB  12  in the same manner as the terminal  40 , wherein the blade  50   a  or the mounting post  83  is urged into an aperture  12   c  of the PCB  12 . 
     As shown in  FIG. 3 , the insertion tool  92  is disposed about the tuning fork type female terminal  30   b  of the terminal  30 , such that the terminal-engagement surfaces  94   b  engage the tool-engagement surfaces  38   b  of the insertion tabs  38 . A force is applied to the tool  92  in the direction of the arrow B, urging the blade  30   a  into the aperture  12   c  until the shoulders  34  engage, and are seated against, the second major surface  12   b . Solder (not shown) may then be applied to the terminal  30  on one or both of the first and second major surfaces  12   a  and  12   b , respectively, to provide an electrical connection therebetween. 
     Each terminal  50  and  70  may also be mounted to the PCB  12  in the same manner as the terminal  30 , wherein the blade  50   a  or the mounting post  73  is urged into an aperture  12   c  of the PCB  12 . In  FIG. 3 , the terminals  50  and  70  are shown subsequent to being assembled in the same manner as the terminal  30 . 
     As further shown in  FIG. 3 , when mounted to the PCB  12 , the insertion tabs  42  of the terminals  40 ,  60 , and  80  are co-planar and aligned linearly along a line L 2 . Similarly, when mounted to the PCB  12 , the insertion tabs  38  of the terminals  30 ,  50 , and  70  are co-planar and aligned linearly along a line L 3 . In the illustrated embodiment, the terminals are mounted such that any one of the terminals  30 ,  50 , and  70  are mounted in an alternating manner with any one of the terminals  40 ,  60 , and  80 . This arrangement ensures that a terminal with the insertion tabs  38  is adjacent a terminal with the insertion tabs  42 . 
     As shown in  FIG. 3 , the insertion tabs  42  of the terminals  40 ,  60 , and  80  and the insertion tabs  38  of the terminals  30 ,  50 , and  70  are axially spaced apart the distance D 1 . This axial spacing allows adjacent terminals to be mounted more closely together than is possible in conventional PCB assemblies, such as the PCB assembly  10  shown in  FIG. 1 . Accordingly, a minimum centerline distance CL 2  between any two adjacent terminals illustrated in  FIG. 3  may be smaller than the centerline distance between terminals in conventional PCB assemblies, such as the PCB assembly  10  illustrated in  FIG. 1 . For example, in the exemplary embodiment illustrated in  FIG. 3 , the centerline distance CL 2  is between about 5.0 mm and about 5.2 mm. Alternatively, the centerline distance CL 2  may be any desired distance, including a distance less than about 5.0 mm and a distance greater than about 5.2 mm. 
     In the illustrated embodiment, adjacent terminals are transversely spaced apart such that an outside surface  38   c  (a representative example of which is shown in the terminal  70  in  FIG. 3 ) of the insertion tabs  38  may be spaced apart a distance D 2  from an outside surface  42   c  (a representative example of which is shown in the terminal  80  in  FIG. 3 ) of the insertion tabs  42 . In the illustrated embodiment, the distance D 2  is about 0.5 mm. Alternatively, the distance D 2  may be any desired distance, including a distance less than about 0.5 mm and a distance greater than about 0.5 mm. 
     As in a conventional PCB assembly, the electrically conductive terminals of the improved PCB assembly  90  may not contact one another. It will be understood that any two terminals ( 30 ,  40 ,  50 ,  60 ,  70 , and  80 ) of the improved PCB assembly  90  may be arranged in any position relative to one another such that they do not touch one another. 
     For example, adjacent terminals may be mounted such that their corresponding insertion tabs,  38  and  42 , are positioned in an overlapping arrangement, but spaced apart a distance such that they do not touch one another. 
     Further, during assembly of the illustrated improved PCB assembly  90 , the space created by the distance D 2  between the outside surfaces  38   c  and the outside surfaces  42   c  allows for the insertion of the tool  92  in the space between adjacent terminals. The distance D 2  between adjacent terminals also has the benefit of providing space for a portion of a non-conductive element, such as a wall of a connector body or of a junction box body, to be disposed and fixed therein between the adjacent terminals. It will be understood however, that the distance D 2  need not be large enough to allow for the insertion of the tool  92  or for a portion of the non-conductive element. 
     The exemplary embodiments of the electrical terminals  30 ,  40 ,  50 ,  60 ,  70  and  80  illustrated in  FIGS. 4 through 9  include first ends configured as blades and second ends configured as tuning fork type female terminals. It will be understood that the first ends of the electrical terminals  30 ,  40 ,  50 ,  60 ,  70  and  80  may have any design, shape or configuration suitable for use in a PCB. Similarly, the second ends of the electrical terminals  30 ,  40 ,  50 ,  60 ,  70  and  80  may have any design, shape or configuration suitable for use in a PCB and requiring one or more insertion tabs thereon. 
     Additionally, each of the exemplary embodiments of the electrical terminals  30 ,  40 ,  50 ,  60 ,  70  and  80  illustrated in  FIGS. 4 through 9  include two insertion tabs formed thereon. It will be understood that the electrical terminals  30 ,  40 ,  50 ,  60 ,  70  and  80  may have any desired number of insertion tabs formed thereon, including having only one insertion tabs formed thereon. 
     The principle and mode of operation of the invention have been described in its preferred embodiments. However, it should be noted that the invention described herein may be practiced otherwise than as specifically illustrated and described without departing from its scope.