Abstract:
An electrical connection box is to be attached to an attachment objective member. The electrical connection box includes: a circuit housing that accommodates a circuit substrate; a fuse box that detachably accommodates a fuse element, the fuse box being provided at an upper portion of the circuit housing in a state where the electrical connection box being attached to the attachment objective member; a plurality of bus bars that connect the circuit substrate and the fuse element; and a water-discharge channel that discharges water flowed into the fuse box to outside of the electrical connection box, the water-discharge channel being provided at a lower part of the bus bars in a state where the electrical connection box is attached to the attachment objective member, and at a position between the circuit housing and the fuse box.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electrical connection box mounted mainly in an automobile. 
     2. Description of the Related Art 
     An electrical connection box mounted in an automobile has been so far installed in an engine compartment and others, depending on the case. Thus, measures have been taken for preventing a short circuit between circuit substrates or between bus bars, due to immersion of water used in washing an automobile (See JP-A-2003-348732). 
     In the conventional electrical connection box, a fixing part for connecting an external connector is integrally provided on an upper face of a frame for accommodating the circuit substrate. The fixing part is provided with a terminal-accommodating hole, which penetrates vertically, in which a terminal having an external connector and a terminal (bus bar) for connecting the circuit substrate part accommodated. Therefore, there is a possibility that water coming from the terminal-accommodating hole may enter into the circuit substrate inside the electrical connection box through the bus bar. 
     Thus, on the channel from the fixing part to the circuit substrate, another component is fitted into an outer circumference of the bus bar hermetically, thereby changing the route of water flowing through the bus bar to protect the circuit substrate from water damage. 
     SUMMARY OF THE INVENTION 
     For example, there is a case where a fuse box (separate body) is provided on the upper part of the casing. In this case, since bus bars are wired from the fuse box to the electrical connection box, raindrops entered into the fuse box flow through the bus bar from the fuse box to the casing. At this time, when raindrops remain on the upper face of the casing, there is a possibility that a short circuit may occur between bus bars, which requires for improvement. 
     The present invention has been completed in view of the above circumstances, and one of objects thereof is to prevent a short circuit between bus bars. 
     According to one aspect of the present invention, there is provided an electric connection box to be attached to an attachment objective member, the electrical connection box including: a circuit housing that accommodates a circuit substrate; a fuse box that detachably accommodates a fuse element, the fuse box being provided at an upper portion of the circuit housing in a state where the electrical connection box being attached to the attachment objective member; a plurality of bus bars that connect the circuit substrate and the fuse element; and a water-discharge channel that discharges water flowed into the fuse box to outside of the electrical connection box, the water-discharge channel being provided at a lower part of the bus bars in a state where the electrical connection box is attached to the attachment objective member, and at a position between the circuit housing and the fuse box. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The objects and advantages of the present invention will become more apparent by describing preferred embodiments thereof in detail with reference to the accompanying drawings, wherein: 
         FIG. 1  is a perspective view showing an electrical connection box of one embodiment in the present invention; 
         FIG. 2  is an exploded perspective view showing the electrical connection box; 
         FIG. 3  is a sectional view of the electrical connection box (showing a state before the upper connector is attached); 
         FIG. 4  is a sectional view of the electrical connection box showing a state of attachment of the upper connector; 
         FIG. 5  is a perspective view of the cover; 
         FIG. 6  is a perspective view of the upper connector, when viewed behind; 
         FIG. 7  shows a horizontal cross section of the fuse box; 
         FIG. 8  is a perspective view of the terminal fitting; and 
         FIG. 9  is a view showing another embodiment (perspective view of the upper connector when viewed behind). 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An embodiment of the present invention will be explained with reference to  FIGS. 1–9 . 
     A member  20  shown in  FIG. 1  is an electrical connection box used in an automobile and provided between a power source such as a battery and an electrical load (electrical components such as lamps and audio products), by which electric power supplied from the power source is distributed and supplied to individual electrical components and also control is performed such as switching of the power supply. The electrical connection box  20  is formed mainly with the body of the connection box  21  for accommodating therein the circuit component  31  in which electrical components  32  such as switching elements being mounted on the circuit substrate  33 , the lower connector  51 , the fuse box  70 , the upper connector  90  (corresponding to the connector housing of the present invention), and it is disposed, for example, inside an engine compartment vertically. 
     In the following description, the vertical direction is based on the assembly or the direction illustrated in  FIG. 3 , and the longitudinal direction is based on the direction illustrated in  FIG. 1 . 
     The body of the connection box  21  is described with reference to  FIG. 2 . 
     The numeral  35  given in the this figure is a frame, which is made of an insulating material, for example, a synthetic resin, and framed so as to surround the outer circumference of the circuit component  31  and accommodate the circuit component  31  therein from above. Both the right and left edges of the frame  35  are provided with the fixing inner wall  37  erected above the figure, and a pair of lock pieces  37 A corresponding to the covers  61  to be described later are provided on an outer wall of each inner wall  37 . 
     A radiator plate  39  is attached on the opening edge on the bottom of the frame  35  (lower face in  FIG. 2 ). 
     The radiator plate  39  is made of a metal and formed in a dimension sufficient to cover an opening on the bottom of the frame  35  and designed to close a whole part of the opening on the bottom, when attached. Further, the radiator plate  39  and the frame  35  are provided respectively with the fixing parts  35 A and  39 A projecting outside the circuit component  31 . These fixing parts  35 A and  39 A are provided with a screw hole and, as shown in  FIG. 4 , fastened against the wall of an engine compartment, with both the fixing parts  35 A and  39 A overlapped, by which the electrical connection box  20  is mounted as a whole. 
     As shown in  FIG. 3 , a substrate bus bar  40  is arranged, which forms an electrically-conductive channel located between the circuit substrate  33  and the radiator plate  39  to distribute a power source. The substrate bus bar  40  is made of a metal plate. An insulating adhesive agent is applied respectively on whole surfaces between the substrate bus bar  40  and circuit substrate  33  and also between the substrate bus bar  40  and the radiator plate  39 , by which each member is adhesively fixed and electrically insulated. An electrical connection with the electrically-conductive channel on the substrate bus bar  40  and the circuit substrate  33  is made, for example, by soldering between a through-hole provided on a jumper wire or circuit substrate  33  and the substrate bus bar  41 . 
     As shown in  FIG. 2 , one end of the substrate bus bar  40  is taken out from the upper edge of the circuit substrate  33  (edge on the right back side in  FIG. 2 ) in line with the circuit substrate  33 . The substrate bus bars  41  arranged in a range from the left corner of the circuit substrate  33  to the slightly right part from the center are designed to be slightly thicker in plate width than the substrate bus bars  46  arranged on the right corner. The substrate bus bar  41  is bent in an L-lettered shape, with the front end pointed to the right backside as shown in  FIG. 2  (the side on which the fuse box  70  to be described later is attached). The front end of the substrate bus bar  41  reaches to the fuse-terminal connecting part  42 , forming a pair of holding pieces  43  which are faced to each other. The groove  44  for accommodating a fuse terminal T is provided between these holding pieces, and when the fuse terminal T is inserted into the groove, the holding pieces  43  are resiliently installed with respect to the fuse terminal T. 
     In contrast, the substrate bus bar  46  is bent in a U-lettered shape, so that the front end is pointed in the direction opposite the fuse-terminal connecting part  42 . The front end of the substrate bus bar  46  is the tab terminal  48  and inserted into the second hood part  96  formed in the upper connector  90  to be described later. A part of the substrate bus bar  46  bent in a U-lettered shape is to be used as a folded part  47 . 
     Further, a lower connector  51  is attached to the lower edge of the circuit substrate  33 . The lower connector  51  is made of a synthetic resin, and in this embodiment three lower connectors are provided in a width direction. The lower connector  51  is provided with a cylindrical hood part  51 A to be fitted into a mating connector. As shown in  FIG. 3 , a terminal fitting  53  bent in an L-lettered shape is fixed by a soldering process to the lower edge of the circuit substrate  33 , and a tab  53 A of the terminal fitting  53  penetrates through the back wall of the lower connector  51  and projects inside the hood part  51 A. 
     Next, a cover  61  is described. The cover  61  is made of a synthetic resin and formed in a dimension sufficient to cover the front of the circuit substrate  33 . A tab supporting piece  62  is provided at the right back corner as shown in  FIG. 2 . The tab supporting piece  62  enters into the folded part  47 , together with a tab supporting shoulder  97  of the upper connector  90  to be described later, and fitted therein without any clearance, when the cover  61  is attached to the frame  35 . 
     The lower edge  63  of the cover  61  extends out over the entire width in the direction opposite the circuit substrate  33  (above in  FIG. 2 ). As shown in  FIG. 3 , in this embodiment, the height of the cover  61  is designed with reference to the mounting components  32  such as relays. However, since the terminal fitting  53  to be jointed to the lower connector  51  is placed at a site higher than other mounting components  32 , in the cover  61 , a part opposed to the terminal fitting  53  is allowed to extend out, thereby avoiding interference of the cover  61  with the terminal fitting  53  at this site. 
     An outer wall  65  is provided as a projection toward the frame  35  at a site opposed to an inner wall  37  of the frame  35 , which is a side edge of the cover  61 , and an outer wall  65  is provided with the lock supporting part  65 A which can be locked by the lock piece  37 A. 
     When the cover  61  is fitted to the frame  35 , these outer walls  65  are allocated so as to surround the inner wall  37  as shown in  FIG. 3 , the upper edge of the cover  61  reaches the bent-up part of respective substrate bus bars  41  (hereinafter, referred to as bent part  41 A) and the lower edge of the cover  61  abuts against the back face  51 B of the lower connector  51 . Then, in a state of such attachment, the lock piece  37 A is locked by the lock supporting part  65 A, thereby holding the cover  61  so as not to prevent falling off from the frame  35 . 
     In the above state, the fuse-terminal connecting part  42  is kept exposed on the body of the connection box  21  and pointed upward as shown in  FIG. 3 . 
     A plurality of seats  64  for fastening the cover  61  to the frame  35  with screws, together with the fuse box  70  to be described later, are provided on the upper edge of the cover  61  or on both right and left ends of the cover. The structure for fastening the fuse box  70  is also described. Of the outer walls  65 , an outer wall around the seats  64  has a lower edge part which is partitioned, and a shoulder  65 B is provided between the outer wall and other outer wall  65 . The shoulder  65 B is positioned at the same height with the plate thickness of a fixing edge  85  to be formed on the fuse box  70 , and a fixing edge  85  is to be fitted into the shoulder  65 B. Then, the fixing part  85  and the seat  64  are overlapped and fastened with a screw, by which the cover  61  and the fuse box  70  are fixed to the frame  35 . The cover  61  and the frame  35  correspond to the water-proof casing of the present invention. 
     The fuse box  70  is made of a synthetic resin and forms a horizontally-long block shape, extending toward a width direction of the circuit substrate  33 . In the fuse box  70 , a part from the left corner to the slightly right from the center as shown in  FIG. 2  is a first accommodating part  71 , and a right half of the remaining part is a second accommodating part  81  in which the folded part  47  of the substrate bus bar  46  is accommodated. 
     The second accommodating part  81  has an opening on the circuit substrate  33  (lower side in  FIG. 2 ) and collectively accommodates a whole folded part  47  of the substrate bus bar  46  from the opening. A supporting groove  82  is provided on three inner walls constituting the second accommodating part  81  at a site opposed to each substrate bus bar  46 . The supporting groove  82  is formed so that the width is the same as that of the substrate bus bar  46 . 
     Next, the first accommodating part  71  is described. 
     An intrusion adjusting wall  77  extending above, as illustrated in the figure, is formed over the entire width of the first accommodating part  71  on the one side face of the first accommodating part  71  (upper face in  FIG. 2 ), and an elastic lock arm  78  extending toward the cover  61  in a cantilever form is provided on the right side edge. A claw  78 A projecting inward is provided at the front end of the elastic lock arm  78 . 
     As shown in  FIG. 3 , the first accommodating part  71  is opened above, in which plural partitioning walls  71 A are provided in the width direction (refer to  FIG. 7 ). Each of the thus partitioned compartments is used as a fuse compartment  72 . A bottom wall  75  of each fuse compartment  72  is provided with a pair of terminal insertion holes  75 A and  75 B as in the direction of S, as shown in  FIG. 3 . Stoppers  74  are provided on both sides of the portioning wall  73  between these terminal insertion holes  75 A and  75 B. The stopper  74  extends above, as shown in the figure, in a cantilever form, and the front end is provided with the lock claw  74 A. 
     Of these terminal insertion holes, the fuse-terminal connecting part  42  of the substrate bus bar  41  is inserted through the right terminal insertion hole  75 A, as shown in  FIG. 3 . A lock hole  45  which can be locked by the lock claw  74 A of the stopper  74  is provided on the fuse-terminal connecting part  42 , and the lock claw  74 A is locked by the lock hole  45 , thereby stopping the fuse-terminal connecting part  42  when the fuse-terminal connecting part  42  is inserted into a normal position, as shown in  FIG. 3 . 
     The fuse-terminal connecting part  105  of a connector bus bar  100  is inserted into the left terminal insertion hole  75 B. As shown in  FIG. 3 , the connector bus bar  100  is bent in a crank form. To be more specific, as shown in  FIG. 8 , the connector bus bars  100  are provided in a form connected back and forth through the joining part  103  between the tab  101  and the fuse-terminal connecting part  105 . Further, a plurality of the connector bus bars  100  are arranged in a width direction in line, and in such a state the entire width of the fuse-terminal connecting part  105  (A dimension shown in  FIG. 8 ) is made narrower than the entire width of the tab  101  (B dimension shown in  FIG. 8 ). 
     As explained above, in order that the width is allowed to change and the tab  101  is connected with the fuse-terminal connecting part  105 , the joining part  103 A is extended inward (back side in  FIG. 8 ) at the outermost connector bus bar  100 A and a traverse extension part  105 B is provided on the bottom of the fuse-terminal connecting part  105  at the connector bus bar  100  B adjacent thereto. Therefore, the fuse-terminal connecting part  105  and the tab  101  are connected at a deviated position in relation to the direction in which connector bus bars  100  are arranged. 
     In addition, an escaping groove  106  is provided at a site opposed to the joining part  103 A or to the traverse extension part  10 B on the bottom of each fuse-terminal connecting part  105  (excluding the outside connector bus bar  100 A) so as not to interfere with the fuse-terminal connecting part  105  of connector bus bar  100  adjacent to the extended joining part  103 A or to the traverse extension part  105 B. Therefore, in a state where all the connector bus bars  100  are arranged, the traverse extension part  105 B and the joining part  103 A enter respectively in the escape groove  106 C of the connector bus bar  100 C and at the escape groove  106 B of the connector bus bar  100 B, thereby preventing interference between the connector bus bars  100  adjacent to each other. 
     The fuse-terminal connecting part  105  of the connector bus bar  100  is provided with a pair of holding pieces  108  at the front end, as the fuse-terminal connecting part  42  of the substrate bus bar  41 , and is also provided with the lock hole  109  corresponding to the lock claw  74 A on the lower side. 
     A fuse H having a pair of fuse terminals T is detachably accommodated into each fuse compartment  72  from above, as shown in the figure. In a state of actual attachment, one fuse terminal T is connected with the connector bus bar  100  and another fuse terminal T is connected with the substrate bus bar  41 , by which the fuse H is melted by heat and cut off, when over-current runs through the bus bar  41  or  100 , thereby protecting an electrical load connected to the circuit component  31  or the upper connector  90 . Further, as shown in  FIG. 3 , in a state where the fuse box  70  is assembled to the frame  35 , the left half of the fuse box  70  projects laterally to the body of the connection box  21 , and the upper connector  90  to be described later is assembled at a lower part of the projected part along the wall  61 A of the cover  61  and from below as shown in the figure. 
     The upper connector  90  is in a horizontally-long shape, extending along the width direction of the fuse box  70 . The first hood part  93  is formed at a site opposed to the first accommodating part  71  and the second hood part  96  is formed at a site opposed to the second accommodating part  81 . Further, in this embodiment, the second hood part  96  is formed with two divided hoods  96 A and  96 B. These two hood parts  93  and  96  are both in a cylindrical shape and open to the same direction as the hood part  51 A of the lower connector  51 , each of which is to be fitted into the respective counterpart connectors (not illustrated). 
     Also as shown in  FIG. 2 , the illustrated back face of the second hood part  96  projects toward the second accommodating part  81  of the fuse box, which is a tab-supporting shoulder  97 . The tab supporting shoulder  97  is able to enter into the second accommodating part  81  and, in a state of assembly, is supported in a state where the folded part  47  of the substrate bus bar  46  is held against the wall of the second accommodating part  81 . 
     In the upper connector  90 , a locking groove  98  is provided in a concave form between the first hood part  93  and the second hood part  96  and facing to the elastic lock arm  78  of the fuse box  70 . The locking groove  98  is provided along the extending direction of the elastic lock arm  78  and penetrates horizontally. It is designed to accommodate the elastic lock arm  78  inside the groove from the front in association with the movement of attaching the upper connector  90 . A lock projected part  99  is formed on the bottom, which can be locked by the claw  78 A of the elastic lock arm  78 . 
       FIG. 6  is a perspective view showing the upper connector  90  from the back or side face facing to the side of the cover  61 . The numeral  91  given in the figure denotes an opposite part and opposed to the lower face  76  on the bottom wall  75  of the first accommodating part  71  when the upper connector  90  is aligned directly opposite the fuse box  70 . For the opposite part  91 , the central part is provided with the first accommodating hole  91 A provided to the first hood part  93 , whereas the upper wall of the second hood part  96  on the left side of the opposite part  91  is provided with the second accommodating hole  96 A. Of these holes, the first accommodating hole  91 A is inserted by the tab  101  of the connector bus bar  100  and the second accommodating hole  96 A is inserted by the tab  48  of the substrate bus bar  46 . 
     One side edge of the opposite part  91  is provided with a guide wall  92  erected above the figure and provided to the side edge of the second hood part  96 . The guide wall  92  is designed to guide a motion of assembling the upper connector  90  to the fuse box  70  by sliding on the side of the fuse box  70  in the course of assembly motion. 
     The front end of the elastic lock arm  78  is fitted into the locking groove  98  and the upper connector  90  is pushed into the fuse box  70 , by which the tab  101  of the connector bus bar  100  enters into the first hood part  93  through the first accommodating hole  91 A, and the tab  48  of the substrate bus bar  46  enters into the second hood part  96  through the second accommodating hole  96 A. Then, the lock projected part  99  passes through the claw  78 A of the elastic lock arm  78 , thereby causing the elastic lock arm  78  to deflect flexibly. 
     Thereafter, the elastic lock arm  78  comes back when the lock projected part  99  passes through the claw  78 A, by which the claw  78 A is positioned in opposition to the lock projected part  99 , thereby keeping the upper connector  90  held by the fuse box  70  so as not to fall off. In a state of such attachment, the end face  92 A of the guide wall  92  is pushed against the intrusion adjusting wall  77  of the fuse box  70 , by which an additional intrusion is adjusted. 
     In this embodiment, the substrate bus bar  41  and the connector bus bar  100  are taken out from the lower face  76  of the fuse box  70 , then, bent in a crank shape and drawn into the cover  61  or the upper connector  90 , following the wiring channel along the lower face  76  (refer to  FIG. 4 ). Thus, once raindrops enter into the fuse chamber  72 , such raindrops soon reach at a bent part of the bus bars  41  and  100  through the substrate bus bar  41  or the connector bus bar  100 . Raindrops will easily remain at the part, and there is a problem of a short circuit between substrate bus bars  41  or connector bus bars  100  which are adjacent to each other. In this embodiment, therefore, a water-discharge channel (water-discharge channel  500 ) is provided between the bent part  41 A of the substrate bus bar  41  and the upper face of the cover  61  as well as between the joining part  103  of the connector bus bar  100  and the opposite face  91  of the upper connector  90 , thereby increasing water-discharge performance. 
     To be more specific, a cover-side water-discharge inclined face  67  is provided on the cover  61 , as shown in  FIG. 5 . The cover-side water-discharge inclined face  67  is positioned in opposition to the first accommodating part  71  of the fuse box  70  and similar in width to the first accommodating part  71 . The water-discharge inclined face  67  starts from the front end of the frame  35  (P part illustrated in  FIG. 3  from which the substrate bus bar  41  is drawn from the inside of the frame  35 ), declining toward the upper connector  90  at about a 45 degree gradient, with the end reaching the wall  61 A of the cover  61 . 
     In contrast, a connector-side water-discharge inclined face  94  is formed over the entire width of the upper part of the first hood part  93 , as shown in  FIG. 6 . The connector-side water-discharge inclined face  94  is provided with the shoulder  95  between the opposite part  91  and the face  94 . Therefore, as shown in  FIG. 4 , the inclined starting edge retracts down below as compared with the lower face  76  of the fuse box  70 . The water-discharge inclined face  94  is declined downward therefrom to the cover  61  at about a 45 degree gradient, with the edge reaching the back face  90 A of the upper connector  90 . These two water-discharge inclined faces  67  and  94  form a mutually opposite and V-shaped water-discharge groove in a state of attachment, or a space for discharging water. Thus, raindrops coming from the substrate bus bar  41  and the connector bus bar  100  are discharged downward through the respective water-discharge inclined faces  67  and  94 , or outside wiring channels of the substrate bus bar  41  and the connector bus bar  100 . 
     Further, the water-discharge inclined face  67  of the cover  61  is provided with three supporting pieces  68  (corresponding to the supporting plate of the present invention) in the width direction. The supporting piece  68  is shaped in a plate form along the water-discharge inclined face  67  in the inclined direction (triangle in this embodiment) and designed to support from beneath the fuse box  70 , with the upper end face in contact with the lower face  76  of the fuse box  70 , at the time of attachment. For example, where the fuse H is exchanged, a downward pressing force acts on the fuse box  70 , and the above structure makes it possible to firmly support the fuse box  70  by the supporting piece  68 . 
     Further, as shown in  FIG. 6 , the connector-side water-discharge inclined face  94  is depressed from both the right and left sides at the back, as shown in the figure. That is, both sides of the connector-side water-discharge inclined face  94  in the upper connector  90  are cut out to form recessed portions that spaces apart from the wall  61 A of the cover  61 . The recessed portions are connected to the opposite part  91  to form an auxiliary water-discharge channel  91 B. The auxiliary water-discharge channel  91 B is for discharging raindrops R flowing to the sides of the opposite part  91 , of those flowing through the connector bus bars  100  (see  FIG. 6 ). 
     Next, the advantages of the embodiment will be described. 
     The fuse H is exchanged, with the hood opened. If the fuse is exchanged, for example, when it rains, raindrops may enter into the fuse compartment  72  of the fuse box  70 . Raindrops entered into the fuse compartment  72  seep out on the lower side  76  of the fuse box  70  through insertion holes  75 A and  75 B provided in the fuse compartment  72 . Thereafter, such raindrops on the substrate bus bar  41  gradually seep out on the cover  61  along the bent part  41 A of the bus bar  41 , and those on the connector bus bar  100  seep out on the upper connector  90  along the joining part  103  of the bus bar  100 . The raindrops soon reach a starting edge of the cover-side water-discharge inclined face  67  or that of the connector-side water-discharge inclined face  94 . Thereafter, the raindrops are discharged downward, namely, outside the wiring channel of the substrate bus bar  41  or of the connector bus bar  100  along the inclined face of the water-discharge inclined face  67  or  94 . 
     In a case where the water-discharge inclined faces  67  and  94  are not provided, raindrops remain over the entire upper edge of the cover  61  and on the opposite part  91  of the upper connector  90 . Therefore, raindrops remain on the lower part of the wiring channel of the bus bars  41  or  100  may cause a short circuit between the substrate bus bars  41  or between the connector bus bars  100 . However, as explained above, the lower part is provided with the water-discharge inclined faces  67  and  94 , by which raindrops flowing through the bus bars  41  and  100  do not remain around the wiring channel of the bus bars  41  or  100  but are discharged outside the wiring channel, thereby preventing a short circuit between the substrate bus bars  41  or between the connector bus bars  100  resulting from raindrops being at the part. In addition, the V-shaped discharge groove formed by the water-discharge inclined faces  67  and  94  is greater in volume and therefore more excellent in discharging water. 
     The present invention is not restricted to the embodiment described with reference to the above description and figures but includes, for example, the following embodiments in the technical field of the invention. In addition, the invention can be executed in various modifications other than examples shown below, without deviating from the scope and object of the invention. 
     (1) In the embodiment described above, the supporting piece  68  is provided only on the cover  61 . However, as shown in  FIG. 9 , the supporting piece  110  may be provided on the water-discharge inclined face  94  of the upper connector  90 . 
     (2) In the embodiment described above, the upper connector  90  is provided separated from the frame  35 . However, the upper connector  90  and the frame  35  may be provided in an integrated form. 
     (3) In the embodiment described above, no water repellent finishing was performed to the water-discharge inclined face  67  or  94 . However, water repellent finishing may be performed to the faces so as to increase water-discharge performance. 
     As described with reference to the embodiments, even if water which has entered into the fuse box enters from the fuse box to the circuit housing through the bus bar, the water-discharge channel provided below the wiring channel of the bus bar from the fuse box to the circuit housing is able to prevent a short circuit that may be caused by water between the bus bars adjacent to each other on the way to the wiring channel. 
     The water-discharge channel is formed with the water-discharge inclined face, thereby increasing water-discharge performance. 
     The fuse box is more stably supported due to the use of the supporting part. 
     The supporting part is shaped in a plate form along the water-discharge inclined face in the inclined direction, so that it will not interfere in the discharge of water. 
     Water such as raindrops remaining between the preventive casing and the fuse box can be discharged, thereby preventing a short circuit which may occur between the bus bars at the site. 
     Water such as raindrops remaining between the connector housing and the fuse box can be discharged, thereby preventing a short circuit which may occur between the bus bars at the site. 
     Since the fitting part is opened downward, raindrops discharged through the water-discharge channel will not enter into the part. 
     A V-shaped groove is formed by the water-discharge inclined face of the preventive casing and that of the connector housing, thereby increasing water-discharge performance. 
     Although the present invention has been shown and described with reference to specific embodiments, various changes and modifications will be apparent to those skilled in the art from the teachings herein. Such changes and modifications as are obvious are deemed to come within the spirit, scope and contemplation of the invention as defined in the appended claims.