Abstract:
An object of the present invention is to provide an electrical connection box in which reduction in weight can be achieved by simplification of the construction, while preventing short-circuiting of a positive electrode side busbar and a negative electrode side busbar. An electrical connection box includes: a positive electrode side busbar connected to a positive electrode of a battery; a negative electrode side busbar connected to a negative electrode of the battery; and a case in which the positive electrode side busbar and the negative electrode side busbar are accommodated. The case includes: a bottom wall; a circumferential wall erected from the bottom wall; and a partition wall erected from the bottom wall. The partition wall is a waterproof partition that partitions a positive electrode side busbar accommodating area and a negative electrode side busbar accommodating area.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an electrical connection box that includes a positive electrode side busbar connected to a positive electrode of a battery, a negative electrode side busbar connected to a negative electrode of the battery, and a case in which the positive electrode side busbar and the negative electrode side busbar are accommodated. 
       BACKGROUND ART 
       [0002]    Various electronic devices are mounted on a vehicle. In order to perform power supply and signal transmission to various electronic devices, the vehicle is provided with a plurality of wire harnesses in which a plurality of electrical wires is bundled. Also, in the vehicle, an electrical connection box used for mutual connection of wire harnesses is disposed at an appropriate position. 
         [0003]    As an example of the electrical connection box, an electrical connection box disclosed in Patent Literature 1 will be described. 
         [0004]    As illustrated in  FIGS. 3 and 4 , the conventional electrical connection box disclosed in Patent Literature 1 includes an upper case  101  and a lower case  102  made of a synthetic resin, and a plurality of wiring boards a, b, c, and d that is stacked and accommodated in the upper case  101  and the lower case  102 . Of the plurality of wiring boards a, b, c, and d, the lowermost wiring board d (wiring board of the lower case  102  side) is configured as a double-sided wiring board in which busbars  104  are disposed on both sides (see  FIG. 4 ). 
         [0005]    Each of the wiring boards a, b, c, and d is configured to include an insulating substrate  103 , and a busbar  104  having a desired pattern on the insulating substrate  103 . In the busbar  104 , connection terminals  105  for input and output are erected upward or downward. In the insulating substrate  103 , terminal insertion holes  106  are drilled such that connection terminals  105  of the adjacent wiring boards a, b, c, and d are inserted. 
         [0006]    In a mounting surface on which the busbars  104  of the respective insulating substrates  103  are mounted, a busbar accommodation groove  115  is provided by protruding ribs  114  at both sides of the busbar  104  according to a desired pattern. In the inner surface of the lower case  102 , a water crosslinking prevention rib  117  protrudes on both sides of the busbar  104 A for a ground circuit along a desired pattern disposed in a rear surface of the lowermost wiring board d (surface of the lower case  102  side). The crosslinking prevention rib  117  is formed according to the shape of the busbar  104 A for the ground circuit and is formed to match with the rib  114  formed in the rear surface of the lowermost wiring board d. Also, both ends of the ribs  114  provided on both sides of the busbar  104 A for the ground circuit are closed by a sealing portion (not illustrated) provided corresponding to the connection terminal  105  of the busbar  104 A for the ground circuit. In the electrical connection box of the related art, the busbar  104 A for the ground circuit in the lowermost wiring board d is surrounded in a sealed state by the rib  114  of the bottom surface of the insulating substrate  103 , the water crosslinking prevention rib  117  of the inner surface of the lower case  102 , and the sealing portion (not illustrated). Thus, the busbar  104 A for the ground circuit is isolated from the other busbars  104 . Therefore, there has been proposed a structure for isolating the busbar  104 A (specific busbar) for the ground circuit and the other busbars  104 . 
       CITATION LIST 
     Patent Literature 
       [0000]    
       
         Patent Literature 1: JP 5-70123 A 
       
     
       SUMMARY OF INVENTION 
     Technical Problem 
       [0008]    However, in the above-described electrical connection box of the related art, the water crosslinking prevention rib  117  is formed according to the shape of the busbar  104 A, and therefore, if the number of busbars  104 A increases, the shape of the crosslinking prevention rib  117  may become complicated and the weight thereof may increase. 
         [0009]    An object of the invention is to provide an electrical connection box in which reduction in weight can be achieved by simplification of construction, while preventing short-circuiting of a positive electrode side busbar and a negative electrode side busbar. 
       Solution to Problem 
       [0010]    In order to achieve the above object, the invention of one aspect is an electrical connection box includes: a positive electrode side busbar connected to a positive electrode of a battery; a negative electrode side busbar connected to a negative electrode of the battery; and a case in which the positive electrode side busbar and the negative electrode side busbar are accommodated, wherein the case includes a bottom wall, a circumferential wall erected from the bottom wall, and a partition wall erected from the bottom wall, and the partition wall is a waterproof partition wall that partitions the positive electrode side busbar accommodation area in which the positive electrode side busbar is accommodated and the negative electrode side busbar accommodation area in which the negative electrode side busbar is accommodated. 
         [0011]    According to the invention, in the invention according to the one aspect, an upper end of the partition wall is positioned above an upper end of the circumferential wall. 
         [0012]    According to the invention, in the invention according to the one aspect, the circumferential wall is provided with a pair of wall portions facing each other, and the partition wall is provided between the pair of wall portions. 
       Advantageous Effects of Invention 
       [0013]    According to the invention of the one aspect, the case includes the bottom wall, the circumferential wall erected from the bottom wall, and the partition wall erected from the bottom wall. The partition wall is separately provided with the positive electrode side busbar accommodation area accommodating the positive electrode side busbar, and the negative electrode side busbar accommodation area accommodating the negative electrode side busbar. The partition wall is the waterproof partition wall that partitions the positive electrode side busbar accommodation area and the negative electrode side busbar accommodation area. Therefore, water is not penetrated over the positive electrode side busbar accommodation area and the negative electrode side busbar accommodation area. It is possible to prevent short-circuiting of the positive electrode side busbar accommodated in the positive electrode side busbar accommodation area and the negative electrode side busbar accommodated in the negative electrode side busbar accommodation area. Since the waterproof partition wall is provided, it is unnecessary to form the crosslinking prevention rib according to the shape of the busbar, as opposed to the related art. The shape of the case can be simplified, and the reduction in the weight of the case can be achieved. 
         [0014]    According to the invention, the upper end of the partition wall is positioned above the upper end of the circumferential wall. For example, even when water is penetrated into the positive electrode side busbar accommodation area and the water level exceeds the upper end of the circumferential wall, the water is discharged from the circumferential wall. Therefore, it is possible to reliably prevent water from being penetrated over the partition wall into the positive electrode side busbar accommodation area and the negative electrode side busbar accommodation area. 
         [0015]    According to the invention, the partition wall is provided such that the entire case is largely divided into two parts. Therefore, it is possible to widely provide the spaces for the positive electrode side busbar accommodation area and the negative electrode side busbar accommodation area. Also, when water is penetrated into the positive electrode side busbar accommodation area and the negative electrode side busbar accommodation area, it is possible to specify the discharge direction of water. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0016]      FIG. 1  illustrates a perspective view of an electrical connection box according to an embodiment of the present invention. 
           [0017]      FIG. 2  illustrates a cross-sectional view taken along line I-I of  FIG. 1 . 
           [0018]      FIG. 3  illustrates an exploded perspective view of an electrical connection box of the related art. 
           [0019]      FIG. 4  illustrates a cross-sectional view of an assembled state of the electrical connection box of the related art illustrated in  FIG. 3 . 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0020]    Hereinafter, an embodiment of an electrical connection box according to the present invention will be described with reference to  FIGS. 1 and 2 . The electrical connection box  1  of the present invention illustrated in  FIGS. 1 and 2  is mounted on a vehicle to supply power to and transmit a signal to electronic devices mounted on the vehicle. Also, in the present invention, a junction block (also called “junction box”), a fuse block (also called “fuse box”), and a relay block (also called “relay box”) are collectively referred to as an electrical connection box. 
         [0021]    The electrical connection box  1  is configured to include a positive electrode side busbar group  2 A (positive electrode side busbar) connected to a positive electrode of a battery, a negative electrode side busbar group  2 B (negative electrode side busbar) connected to a negative electrode of the battery, and a lower case  3  (case) in which the positive electrode side busbar group  2 A, the negative electrode side busbar group  2 B, a plurality of electrical parts (not illustrated) connected to the busbar groups  2 A and  2 B are accommodated, and an upper case (not illustrated) assembled to the lower case  3 . The electrical connection box  1  is fixed to a battery case that is attached to a vehicle body. 
         [0022]    The positive electrode side busbar group  2 A and the negative electrode side busbar group  2 B are provided with a plurality of busbars  2 . The respective busbars  2  are obtained by performing punching and bending process on a conductive sheet metal, and a pair of connection terminals  20  bent upward is formed on both sides thereof. A terminal of an electrical part (relay or fuse) mounted on the lower case  3  or a terminal of a connector is connected to the pair of connection terminals  20 . 
         [0023]    The lower case  3  is made of an insulating synthetic resin. The lower case  3  is formed in a bottom plate shape by integrally including a bottom wall  4  having a rectangular plate shape, a circumferential wall  5  erected from the periphery of the bottom wall  4 , and a partition wall  6  erected from the bottom wall  4  and partitioning the inside of the circumferential wall  5 . 
         [0024]    Herein, a direction of an arrow Y in  FIG. 1  indicates a length direction of the bottom wall  4 , a direction of an arrow X in  FIG. 1  indicates a width direction of the bottom wall  4 , and a direction of an arrow Z in  FIG. 1  indicates a standing direction and a height direction of the circumferential wall  5  perpendicular to both the arrow Y and the arrow X. 
         [0025]    The bottom wall  4  is provided with a positive electrode side busbar accommodation area  41  in which the positive electrode side busbar group  2 A is placed, and a negative electrode side busbar accommodation area  42  in which the negative electrode side busbar group  2 B is placed. The positive electrode side busbar accommodation area  41  and the negative electrode side busbar accommodation area  42  are provided along the length direction of the bottom wall  4  (direction of the arrow Y). 
         [0026]    Busbar attachment portions  43  for attaching the busbars  2  to the bottom wall  4  are provided in the positive electrode side busbar accommodation area  41  and the negative electrode side busbar accommodation area  42 , respectively. The busbar attachment portion  43  protrudes from the bottom wall  4  on both sides of each busbar  2 . The busbar attachment portions  43  are provided in parallel to one another, and the busbars  2  are positioned therebetween. A height dimension of the busbar attachment portion  43  is slightly higher than a thickness dimension of the busbar  2  and is lower than a height dimension of the circumferential wall  5  to be described below and the partition wall  6 . 
         [0027]    The circumferential wall  5  includes a first wall portion  51  and a second wall portion  52 , which are provided along the length direction of the bottom wall  4  and face each other, and a third wall portion  53  and a fourth wall portion  54 , which are provided along the width direction of the bottom wall  4  and face each other. The third wall portion  53  is provided on the positive electrode side busbar accommodation area  41 , and the fourth wall portion is provided on the negative electrode side busbar accommodation area  42 . The first wall portion  51  and the second wall portion  52  correspond to “a pair of wall portions” described in claims. 
         [0028]    In the circumferential wall  5 , the second, third, and fourth wall portions  52 ,  53 , and  54  are formed to have a constant height dimension. In the first wall portion  51 , a portion (hereinafter, referred to as a high wall portion  55 ), of which a height dimension is higher than other wall portions (that is, the second, third, and fourth wall portions  52 ,  53 , and  54 ), is provided. The high wall portion  55  is a part of the first wall portion  51  provided on the positive electrode side busbar accommodation area  41  side of the partition wall  6  (which will be described below). One end of the high wall portion  55  is provided at a position spaced apart from the third wall portion  53 , and the other end thereof is provided continuously to the partition wall  6 . 
         [0029]    The partition wall  6  is continuously provided over the second wall portion  52  from the first wall portion  51  of the circumferential wall  5  and is provided between the positive electrode side busbar accommodation area  41  and the negative electrode side busbar accommodation area  42  to partition the positive electrode side busbar accommodation area  41  and the negative electrode side busbar accommodation area  42 . 
         [0030]    The partition wall  6  is configured to include a first partition wall  61  that is continuous to the inner surface of the first wall portion  51  and formed by extending toward the second wall portion  52 , a second partition wall  62  that is continuous to the first partition wall  61  and formed by extending in the fourth wall portion  54 , a third partition wall  63  that is continuous to the second partition wall  62  and formed by extending toward the second wall portion  52 , a fourth partition wall  64  that is continuous to the third partition wall  63  and formed by extending toward the third wall portion  53 , and a fifth partition wall  65  that is continuous to the fourth partition wall  64  and formed by extending in the second wall portion  52  and continued to the inner surface of the second wall portion  52 . Also, the first partition wall  61  and the fifth partition wall  65  are provided on a straight line with each other, and the first partition wall  61 , the fifth partition wall  65 , and the third partition wall  63  are provided in parallel. The second partition wall  62  and the fourth partition wall  64  are provided to face each other and are formed to have substantially the same dimension along the length direction of the bottom wall  4 . 
         [0031]    Also, the second, third, fourth, and fifth partition walls  62 ,  63 ,  64 , and  65  are formed to have the same height dimension. The first partition wall  61  is formed to have a height dimension slightly lower than the second, third, fourth, and fifth partition walls  62 ,  63 ,  64 , and  65 . The height dimension of the first partition wall  61  is formed to be substantially the same as the height dimension of the high wall portion  55  of the circumferential wall  5 . 
         [0032]    Furthermore, in the lower case  3 , the positive electrode side busbar accommodation area  41 , that is, the erected wall  7  erected from the bottom wall  4  in a plate shape, is provided. The erected wall  7  has one end continuous to a boundary between the first wall portion  51  and the high wall portion  55  of the circumferential wall  5 , and the other end extending toward the second wall portion  52 . The erected wall  7  is formed to have substantially the same height dimension as the highest portion (second, third, fourth, and fifth partition walls  62 ,  63 ,  64 , and  65 ) in the partition wall  6 . 
         [0033]    In the electrical connection box  1 , the lower case  3  includes the bottom wall  4 , the circumferential wall  5  erected from the bottom wall  4 , and the partition wall  6  erected from the bottom wall  4 , and the partition wall  6  is the waterproof partition wall  6  partitioning the positive electrode side busbar accommodation area  41  accommodating the positive electrode side busbar group  2 A and the negative electrode side busbar accommodation area  42  accommodating the negative electrode side busbar group  2 B, which are separately provided. Therefore, water is not penetrated over the positive electrode side busbar accommodation area  41  and the negative electrode side busbar accommodation area  42 . It is possible to prevent short-circuiting of the positive electrode side busbar group  2 A accommodated in the positive electrode side busbar accommodation area  41  and the negative electrode side busbar group  2 B accommodated in the negative electrode side busbar accommodation area  42 . Also, the waterproof partition wall  6  is provided, the shape of the lower case  3  can be simplified, and the reduction in the weight of the lower case  3  can be achieved. 
         [0034]    In the above-described embodiment, the partition wall is provided from the first partition wall  61  over the second partition wall  62 , but may be provided from the third partition wall  63  over the fourth partition wall  64 . Also, the positive electrode side busbar accommodation area  41  may be provided in the central portion of the bottom wall  4 , and the partition wall  6  may be provided to surround the positive electrode side busbar accommodation area  41 . That is, the partition wall  6  may be not continuous to the inner surface of the circumferential wall  5 . Also, the partition wall  6  may be provided, for example, between the adjacent wall portions  51  and  52 , and both ends thereof may be continuous to the same wall portion  51 . 
         [0035]    Also, in the above-described embodiment, the electrical connection box  1  is mounted with the positive electrode side busbar group  2 A and the negative electrode side busbar group  2 B connected to a high voltage battery, but the electrical connection box  1  may be mounted with busbars connected to a low voltage battery, of which a voltage is lower than the high voltage battery. In that case, both the positive electrode side busbar for the low voltage connected to the positive electrode of the low voltage battery and the negative electrode side busbar for the low voltage connected to the negative electrode of the low voltage battery may be accommodated in the negative electrode side busbar accommodation area  42 . 
         [0036]    Also, the above-described embodiments are merely the representative form of the present invention, and the present invention is not limited to the embodiments. That is, various modifications can be made without departing from the scope of the present invention. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           1  electrical connection box 
           2 A positive electrode side busbar (positive electrode side busbar group) 
           2 B negative electrode side busbar (negative electrode side busbar group) 
           3  case (lower case) 
           4  bottom wall 
           5  circumferential wall 
           6  partition wall 
           41  positive electrode side busbar accommodation area 
           42  negative electrode side busbar accommodation area 
           51  first wall portion (pair of wall portions) 
           52  second wall portion (pair of wall portions)