Patent Publication Number: US-6910923-B2

Title: Fuse module

Description:
BACKGROUND OF THE INVENTION 
   This invention relates to a fuse module to be assembled into an electrical connection box used for, e.g., an automotive vehicle and the like. 
   A known electrical connection box has a fuse mounting section  301  which is formed on an outer surface of a casing  300  and in which a multitude of fuses are mounted as shown in FIG.  12 . Further, a fuse in which connection terminals  312  connected with the opposite ends of a fusing element  311  are covered by an insulating member  314  except their leading ends as shown in  FIG. 13  is known as a fuse  310  to be mounted in the fuse mounting section  301 . 
   Such a fuse  310  is mounted in the fuse mounting section  301  by inserting the connection terminals  312  of the fuse  310  into forked inserting portions  303  of tab terminals  302  formed at the leading ends of a busbar provided in the fuse mounting section  310  as shown in FIG.  14 . 
   In recent years, automotive vehicles have been demanded to have comfortable equipments while being demanded to improve its comfort in a passenger&#39;s compartment. In order to simultaneously satisfy these contradictory demands, electrical connection boxes used in automotive vehicles need to be smaller and more lightweight while circuits for the comfortable equipments are on the increase. 
   However, as the comfortable equipments increase as described above, the number of fuses for protecting the equipments from an overcurrent tends to increase. Further, the insulating member  314  of the fuse projects above the tab terminals  302  as shown in  FIG. 14  to thereby make a conventional fuse mounting structure bulky. This hinders the electrical connection boxes from becoming smaller and more lightweight. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide a fuse module which is free from the problems residing in the prior art. 
   According to an aspect of the present invention, a fuse module comprises a plurality of fuses each having a fusing element and terminal sections at opposite ends of the fusing element, and a fuse casing for accommodating all of these plurality of fuses. The fuse casing is made of an insulating material, and formed with external terminal insertion holes. 
   These and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description and accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view showing a fuse module according to a first embodiment of the invention; 
       FIG. 2  is a section view along the line  2 — 2  in  FIG. 1 ; 
       FIG. 3  is a perspective view showing part of a busbar having a tab terminal to be connected with an input/output terminal of the fuse module; 
       FIG. 4  is an equivalent circuit diagram of a fuse circuit formed by the fuse module; 
       FIG. 5  is an exploded perspective view showing an entire fuse module according to a second embodiment of the invention; 
       FIG. 6  is a plan view showing the fuse module (without a cover) of  FIG. 5 ; 
       FIG. 7  is a section view along the line  7 — 7  in  FIG. 6 ; 
       FIG. 8  is a section view along the line  8 — 8  in  FIG. 6 ; 
       FIGS. 9A  to  9 C are equivalent circuit diagrams of fuse circuits formed by the fuse module of  FIG. 5 ; 
       FIGS. 10A  to  10 C are diagrams showing a mode of a tab terminal with which the fuse module of  FIG. 5  is to be connected; 
       FIGS. 11A  to  11 C are diagrams showing another mode of a tab terminal with which the fuse module of  FIG. 5  is to be connected; 
       FIG. 12  is a perspective view showing an external configuration of a conventional electrical connection box; 
       FIG. 13  is a perspective view showing an external configuration of a conventional fuse; and 
       FIG. 14  is a perspective view showing a state where the conventional fuse is mounted into connection with a tab terminals. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
   Referring to  FIGS. 1  to  4  showing an embodiment of the present invention, a fuse module is comprised of an insulating fuse casing  10 , a plurality of fuses  1  provided in the fuse casing  10 , and shorting members  20  mounted in the fuse casing  10 . 
   Each fuse  1  has a plate-shaped construction in which an input terminal  3  and an output terminal  4  are integrally connected with the opposite ends of a fusing element  2 , and is entirely made of an electrically conductive material. The input terminals  3  and the output terminals  4  are both substantially in the form of a rectangle, and the input terminals  3  have the same height as the output terminals  4 , but are wider than them. The shape, width and the like of the fusing elements  2  are adjusted according to their fusing characteristics, i.e., fuse capacities. For example, the fusing elements  2  of the fuses  1 B are convex, whereas those of the fuses  1 C are sinuous like an ac signal waveform. The fuses  1 D are mirror images of the fuses  1 C. 
   The fuse casing  10  is formed with an opening  11  and shorting member insertion holes  13 ,  14 , and includes a casing main body  10 A and a cover  10 B for closing the opening  11 . Fuse mount holes  16  are formed inside a base portion  15  exposed at the opening  11  of the casing main body  10 A. 
   A plurality of fuse mount holes  16 , seventeen in the shown example, are arrayed at specified intervals in each of two rows D, E shown in  FIG. 1  along the longitudinal direction of the casing main body  10 A in the form of a rectangular parallelepiped. Each mount hole  16  is so formed that the plate-shaped fuse  1  can be vertically mounted, i.e., with the bottom ends of the input and output terminals  3 ,  4  faced down, and is comprised of an input terminal mounting portion  16   a  in which the input terminal  3  is mounted, a fusing element mounting portion  16   b  in which the fusing element  2  is mounted, and an output terminal mounting portion  16   c  in which the output terminal  4  is mounted, the portions  16   a ,  16   b  and  16   c  being continuous in horizontal direction. Distance L 2  between the outer end of the input terminal mounting portion  16   a  and the outer end of the output terminal mounting portion  16   c  is set substantially equal to distance L 1  between the opposite ends of the fuse  1 . The input terminal mounting portion  16   a  is formed longer than the output terminal mounting portion  16   c  in view of the fact that the input terminal  3  is wider than the output terminal  4 . 
   At an upper edge of each fuse mount hole  16 , an opening  17  communicating with the input terminal mounting portion  16   a , the fusing element mounting portion  16   b  and the output terminal mounting portion  16   c  is defined in the base portion  15 . In both rows D and E, the input terminal mounting portions  16   a  are arranged at the sides closer to the outer surfaces of the casing main body  10 A. In other words, the input terminal mounting portions  16   a  of the row D and those of the row E extend in opposite directions. 
   Further, the width of the input and output terminal mounting portions  16   a ,  16   b  is substantially equal to that of the plate-shaped fuses  1 , so that the input and output terminals  3 ,  4  at the opposite sides of the fuses  1  can be securely held without shaking. Further, the width of the fusing element mounting portions  16   b  is set sufficiently larger than that of the plate-shaped fuses  1 , so that clearances are defined at the opposite sides of the fuses  1  mounted in the fuse mounting holes  16 . Thus, the mounted fuses  1  can be easily taken out using these clearances. 
   As shown in  FIG. 2 , the fuses  1  are individually mounted in the respective fuse mount holes  16 , which are formed with tab terminal insertion holes  18 ,  19  as external terminal insertion holes. The tab terminal insertion hole  18  is for an input tab terminal and a tab terminal  31  formed by bending an end of an input-side busbar  30  is inserted thereinto, and the tab terminal insertion hole  19  is for an output tab terminal and a tab terminal  33  formed by bending an end of an output-side busbar  32  is inserted thereinto. Each tab terminal  31 ,  33  is formed with a forked inserting portion  31   a ,  33   a  in its center along widthwise direction (F) as shown in FIG.  3 . 
   The tab terminal insertion hole  18  is so formed as to have the same horizontal cross section from its opening  18   a  to its inner back  18   b , and intersects with, e.g., is normal to the input terminal mounting portion  16   a . The other tab terminal insertion hole  19  is also so formed as to have the same horizontal cross section from its opening  19   a  to its inner back  19   b , and intersects with, e.g., is normal to the output terminal mounting portion  16   c.    
   Accordingly, when the tab terminals  31 ,  33  are inserted through the respective tab terminal insertion holes  18 ,  19  as described later, the input terminal  3  of the fuse  1  is inserted into the forked inserting portion  31   a  of the tab terminal  31  to connect the input-side busbar  30  and the input terminal  3 , whereas the output terminal  4  of the fuse  1  is inserted into the forked inserting portion  33   a  of the tab terminal  33  to connect the output-side busbar  32  and the output terminal  4 . Although the tab terminals  33  of the output-side busbar  32  are mounted into all the fuse mount holes  16 , the tab terminals of the input-side busbar  30  are mounted into part of the fuse mount holes  16 . This is described later. 
   As shown in  FIGS. 1 and 2 , the shorting member insertion hole  13  is horizontally formed from the side surface  11   a  of the casing main body  10 A at the side of the row D, whereas the shorting member insertion hole  14  is horizontally formed from the side surface  11   b  of the casing main body  10 A at the side of the row E. A plurality of shorting members  20  made of an electrically conductive material, e.g., four shorting members  20 A,  20 B,  20 C and  20 D are inserted into the shorting member insertion hole  13 , whereas a plurality of shorting members  20 , e.g., two shorting members  20 E and  20 F are inserted into the shorting member insertion hole  14  (see FIG.  1 ). 
   The shorting members  20 A,  20 B are both constructed such that two comb-shaped press-contact blades  21  are provided at a coupling portion  22 ; the shorting members  20 C and  20 E are both constructed such that three comb-shaped press-contact blades  21  are provided at the coupling portion  22 ; the shorting member  20 D is constructed such that eight comb-shaped press-contact blades  21  are provided at the coupling portion  22 ; and the shorting member  20 F is constructed such that fourteen comb-shaped press-contact blades  21  are provided at the coupling portion  2 . An interval between adjacent press-contact blades  21  is the same as the interval between adjacent fuse mount holes  16 . The shorting members  20 A and  20 B may have the same construction, and the shorting members  20 C and  20 E may also have the same construction. 
   The shorting member insertion holes  13 ,  14  are comprised of coupling portion inserting portions  13   a ,  14   a  in which the coupling portions  22  are inserted, and blade inserting portion  13   b ,  14   b  in which the press-contact blades  21  are inserted, respectively. The coupling portion inserting portions  13   a ,  14   a  are formed to have a width substantially equal to the length of the casing main body  10 A, whereas the blade inserting portions  13   b ,  14   b  are formed to have such a width as to allow one press-contact blade  21  is insertable thereinto. The shorting member insertion hole  13 ,  14  is such that a plurality of blade inserting portions  13   b ,  14   b  are branched off from one coupling portion inserting portion  13   a ,  14   a.    
   When the shorting members  20  are inserted into the thus formed shorting member insertion holes  13 ,  14 , the input terminals  3  are inserted into clearances of all the press-contact blades  21  provided in the shorting members  20  since the intervals between adjacent press-contact blades  21  is the same as the interval between adjacent fuse mount holes  16 , with the result that a plurality of input terminals  3  are shorted with each other by the shorting members  20 . It should be noted that no press-contact blade  21  of the shorting member  20  is connected with the first fuse  1 E of the row D. 
   The fuse module of this embodiment is completed by mounting the cover  10 B to close the opening  11  of the casing main body  10 A in which the fuses  1  and the shorting members  20  are mounted as described above and securing it by an adhesive or the like. 
   When the completed fuse module is mounted in a fuse module mounting section  51  formed by recessing in an electrical connection box  50  as shown in  FIG. 2 , the input terminals  3  are inserted into the forked inserting portions  31   a  of the tab terminals  31  provided in a connection casing  52  mounted beforehand below the mounting section  51  and projecting upward from the connection casing  52  to be electrically connected while the output terminals  4  are inserted into the forked inserting portions  33   a  of the tab terminals  33  to be electrically connected. This connection is made at once for all tab terminals  31  and all tab terminals  33  by mounting the fuse module in the fuse module mounting section  51 . In this way, fuse circuits having equivalent circuits shown in  FIG. 4 , i.e., circuits in which a plurality of fusing elements  2  and output terminals are connected in parallel with a common power supply is formed. No shorting member  20  is connected with the fuse  1 E described above, and the busbars  30 ,  32  are directly connected with a single input terminal  3  and a single output terminal  4 . 
   In the fuse module according to this embodiment described in detail above, since a plurality of fuses  1  are arranged in the fuse casing  10 , it is not necessary to insulate the fuses  1  themselves by insulating members unlike the prior art, the fuse module can be, therefore, lighter by eliminating the need for the insulating members. Further, since the terminals  3 ,  4  need not be covered by insulating members and it is sufficient for the output terminals  4  to have at least such a size as to be connectable with the tab terminals  33  and for the input terminals  3  to have at least such a size as to be connectable with tab terminals  31  and the shorting members  20 , it is possible to reduce the sizes of the terminals  3 ,  4 . As a result, the fuse module can be made smaller. 
   Since the fuses  1  are individually mounted in the fuse mount holes  16  formed in the insulating fuse casing  10  in the first embodiment, they are insulated from each other. Further, since the fuses  1  are vertically mounted in the fuse mount holes  16 , a mounting area can be made smaller, thereby enabling the fuse module to be smaller. Since the width of the terminal mounting portions  16   a ,  16   c  is substantially equal to the thickness of the fuses  1 , the fuses  1  can be securely held without shaking by the terminal mounting portions  16   a ,  16   c  located at the opposite ends of the fuses  1 . Further, since the spacing between the terminals  3 ,  4  of the fuses  1  is constant among the fuses  1 , desired fuses  1  can be mounted in the fuse mount holes  16 . If the fuse capacity is the same, the fuses  1  can be used without being chosen. Furthermore, since the width of the fusing element mounting portions  16   b  is larger than the thickness of the fuses  1 , the clearances are formed between the fusing elements  2  of the fuses  1  mounted in the fuse mount holes  16  and the fusing element mounting portions  16   b  and the fuses  1  can be, therefore, easily taken out using these clearances. 
   In this embodiment, when the shorting member  20  is engaged with a plurality of input terminals  3 , the engaged input terminals  3  are shorted with each other since the shorting member  20  is electrically conductive. Thus, it is sufficient to connect at least one of the plurality of shorted input terminals  3  with the tab terminals  31  of the busbar  30 , making it possible to simplify the busbar  30 . Since the electrically conductive shorting member  20  is engaged with the input terminals  3  arrayed in the same row, a plurality of input terminals  3  are simultaneously engaged and shorted, thereby improving the mountability of the shorting member  20 . Further, since each shorting member  20  includes a plurality of comb-shaped press-contact blades  21  engageable with a plurality of input terminals  3  by holding them from opposite sides, the respective press-contact blades  21  and the respective input terminals  3  are simultaneously engaged by pushing the shorting member  20  such that the respective input terminals  3  are inserted into the press-contact blades  21 . Thus, the input terminals  3  can be shorted by a simple operation. Furthermore, since a plurality of press-contact blades  21  are provided at the same intervals and the input terminals  3  are arrayed at the same intervals as the press-contact blades  21 , it is not necessary to choose the input terminal  3  to be shorted. Further, since the input terminals  3  are arranged to face the outer side of the casing main body  10 A and the shorting members  20  are inserted into the casing main body  10 A from outside, it is not necessary to provide the shorting members  20  in a narrow space inside the casing main body  10 A and a shorting operation by the shorting members  20  can be easily performed. 
   In the foregoing embodiment, the input terminals  3  of the fuses  1  are wider than the output terminals  4  thereof. This is in consideration of connection of the shorting members  20  with the press-contact blades  21 . However, the present invention is not limited to such dimensioning. For example, the input and output terminals  3 ,  4  are allowed have the same width by shortening the length of the press-contact blades  21 . This enables the fuse module to be even smaller. 
   Although the fuses  1  are linearly arrayed in two rows in the foregoing embodiment, the present invention is not limited thereto. For example, the fuses may be linearly arrayed in one row or may be arrayed along an outer periphery of the fuse casing. 
   Further, although the numbers of the press-contact blades provided in the shorting members are two, three, four, eight and fourteen in the foregoing embodiment, the present invention is not limited thereto. It should be appreciated that a shorting member having a desired number of press-contact blades may be so used as to conform to a fuse circuit to be designed. 
     FIG. 5  is an exploded perspective view showing an entire fuse module according to another embodiment of the invention,  FIG. 6  is a plan view showing the fuse module (without a cover) of  FIG. 5 ,  FIG. 7  is a section view along the line  7 — 7  in FIG.  6  and  FIG. 8  is a section view along the line  8 — 8  in FIG.  6 .  FIGS. 7 and 8  show also the cover. 
   As shown in  FIG. 5 , a fuse module  101  is provided with a plurality of fuses  102  each having terminal sections  104 ,  105  at the opposite ends of a fusing element  103 ; a plurality of connection terminals (output terminals)  110  formed separately from the fuses  102  and including first connecting portions  111  to be connected with the terminal sections  104  and second connecting portions  112  to be connected with unillustrated external terminals; a plurality of connection terminals (input terminals)  120  formed similarly and including first connecting portions  121  to be connected with the terminal sections  105  and second connecting portions  122  to be connected with unillustrated external terminals; and an insulating fuse casing  130  for accommodating these fuses  102  and connection terminals  110 ,  120 . 
   Each fuse  102  is made of an electrically conductive metallic material integrally having the fusing element  103  and the terminal sections  104 ,  105  described above. The fusing element  103  is formed into a desired shape in conformity with its fusing characteristic, i.e., fuse capacity. For example, the fusing elements  103   a  are moderately pointed; the fusing elements  103   b  are steeply pointed; and the fusing elements  103   c  are sinuous, each waveform having a narrow width. The shape and size of the terminal sections  104 ,  105  are so specified as to be same among the respective fuses  102 , and spacing L 3  between them is also so specified as to be same among the respective fuses  102 . 
   The fuse casing  130  is comprised of a casing main body  131  having an opening  131   a  and a cover  132  for closing the opening  131   a , and is made of an insulating material, e.g., an insulating resin. Recesses  134  for mounting the fuses  102  are provided in the casing main body  131  as shown in  FIGS. 5 ,  7  and  8 . Three rows of the recesses  134  are arrayed at specified intervals along direction Y, and walls  135  are formed around the recesses  134 . 
   At an inner side of a base wall  133  of each recess  134  are formed connecting portion mount holes  136   a ,  136   b  for mounting the second connecting portion  112  of the output-side connection terminal  110  and the second connecting portion  122  of the input-side connection terminal  122  as shown in FIG.  7 . Projections  137   a ,  137   b  for supporting the first connecting portion  111  of the connection terminal  110  and the first connecting portion  121  of the connection terminal  120  are formed near the mount holes  136   a ,  136   b . The projections  137   a ,  137   b  are provided between the mount holes  136   a  and  136   b . The mount holes  136   a ,  136   b  and the projections  137   a ,  137   b  constitute connection terminal holding portions. Below the mount holes  136   a ,  136   b , tab terminal insertion holes  138   a ,  138   b  as external terminal insertion holes are formed to extend in a direction substantially normal to the mount holes  136   a ,  136   b  in plan view and to reach a bottom surface  139 . 
   The connection terminal  110  has one each of the first and second connecting portions  111 ,  112 , wherein the first connecting portion  111  is so bent as to be substantially normal to the second connecting portion  112  and the second connecting portion  112  is formed with a forked inserting portion  112   a . The connection terminal  110  is mounted in the casing main body  131  by inserting the second connecting portion  112  into the connecting portion mount hole  136   a  until the lower surface of a horizontal portion of the first connecting portion  111  comes into contact with the projection  137   a . At this stage, the second connecting portion  112   s  are in a state where they are connectable with tab terminals  140  to be described later via the tab terminal insertion holes  138   a.    
   On the other hand, the connection terminals  120  include first and second connecting portions  121 ,  122 , wherein the first connecting portions  121  are so bent as to be substantially normal to the second connecting portions  122 . Each first connecting portion  121  has its length so adjusted as to be connectable with the connecting portion(s)  105  of one, two or any desired number of fuses  102 . For example, the first connecting portion  121  of the connection terminal ( 120   a ) in left row H shown in  FIGS. 5 and 6  has such a length as to be connectable with the terminal sections  105  of twelve fuses  102 . The first connecting portions  121  of the connection terminals ( 120   b ), ( 120   c ), ( 120   d ) and ( 120   e ) from the uppermost to the bottommost position in middle row I have such lengths as to be connectable with the terminal sections  105  of three fuses  102 , that of one fuse  102 , those of two fuses  102  and those of two fuses  102 , respectively. The first connecting portion  121  of the upper connection terminal ( 120   f ) and that of the lower connection terminal ( 120   g ) in right row J have such lengths as to be connectable with the terminal sections  105  of eight fuses  102  and those of four fuses  102 . 
   Each connection terminal  120  includes one, two or more second connecting portions  122 . For example, as shown in  FIG. 5 , the connection terminal ( 120   a ) in the left row H have three second connecting portions  122 ; each of the connection terminals ( 120   b ), ( 120   c ), ( 120   d ), ( 120   e ) from the uppermost to the bottommost position in the middle row I has one second connecting portion  122 ; and each of the upper and lower connection terminals ( 120   f ), ( 120   g ) in the right row J has two second connecting portions  122 . Further, each second connecting portion  122  is formed with a forked inserting portions  122   a.    
   Each connection terminal  120  having the second connecting portion(s)  122  is mounted in the casing main body  131  by inserting the second connecting portion(s)  122  into the connecting portion mount hole(s)  136   a  until the lower surface of a horizontal portion of the first connecting portion  121  comes into contact with the projection  137   b . At this stage, the second connecting portions  122  are in a state where they are connectable with the tab terminals  140  to be described later via the tab terminal insertion holes  138   b . It should be noted that portions of the walls  135  are omitted so that the first connecting portions  121  have a specified height, and identified by  135   a  in  FIGS. 5  to  7  are these omitted portions of the walls  135 . The first connecting portions  111 ,  121  mounted in the casing main body  131  as described above are located substantially on the same plane (substantially at the same height position) as shown in  FIGS. 7 and 8 . Further, one mount hole  136   a  and one mount hole  136   b  are provided in each recess  34 . 
   Spacing L 4  between the first connecting portions  111  of the connection terminals  110  and the first connecting portions  121  of the connection terminals  120  is equal to the spacing L 3  between the terminal sections  104  and  105  of the fuses  102 . The shape and size of the first connecting portions  111 ,  121  are same as those of the terminal sections  104 ,  105  of the fuses  102 . 
   The terminal sections  104 ,  105  of the fuses  102  are mounted by, e.g., soldering on the first connecting portions  111 ,  121  of the connection terminals  110 ,  120  mounted in the casing main body  131  as described above. The number of the terminal sections  105  corresponding to the first connecting portion  121  is set at a desired value depending on the connection terminal  120  to be used. The mounted fuses  102  are arrayed in three rows at specified intervals in direction Y normal to a spaced-apart direction X of the terminal sections  104 ,  105  as shown in FIG.  6  and are located substantially on the same plane (substantially at the same height position) as shown in  FIGS. 7 and 8 . 
   A circuitry of the fuse module in which the connection terminals  110 ,  120  and the fuses  102  are thus connected forms, for example, fuse circuits shown in  FIGS. 9A  to  9 C. In other words, one connection terminal ( 120   a ,  120   b ,  120   d ,  120   e ,  120   f ,  120   g ) can be connected with the terminal sections  105  of two or more fuses  102 , thereby forming a branched fuse circuit. 
   The fuse module of the second embodiment is completed when the cover  132  is put on the casing main body  131  in which the connection terminals  110 ,  120  and the fuses  102  are mounted through the opening  131   a . Projections  132   a  to be located above the walls  135  and projections  132   b  to be located above the fuses  102  are formed on the inner surface of the cover  132 . When the cover  132  is fitted to close the opening  131   a , it prevents the adjacent fuses  102  from coming into contact with each other to cause a short circuit and prevents the fuse  102  from shifting even if the fuses  102  are displaced, for example, upon being subjected to an external impact or upon being turned upside down. 
   In this completed fuse module, as shown in  FIG. 8 , the tab terminals  140  formed at leading ends of busbars are inserted into the forked inserting portions  112   a ,  122   a  provided at the second connecting portions  112 ,  122  upon being inserted through the tab terminal insertion holes  138   a ,  138   b , thereby electrically connecting the tab terminals  140  with the second connecting portions  112 ,  122 . At this time, each connection terminal ( 120   a ,  120   f ,  120   g ) having two or more second connecting portions  122  has at least one second connecting portion  122  connected with the tab terminal  140 . It should be noted that the tab terminal is formed by bending one end of a busbar having the other end thereof connected with an electric circuit built in an electrical connection box and is, for example, as shown in  FIGS. 10A  to  11 C. A tab terminal  140 A shown in  FIGS. 10A  to  10 C is formed by beveling corners at the longer sides of an end (upper end) of a flat plate, whereas a tab terminal  140 B shown in  FIGS. 11A  to  11 C is formed by beveling corners at all sides of an end (upper end) of a flat plate. The tab terminal may take another construction. 
   As described above, since the entire fuse module  101  is covered by the insulating fuse casing  130  in the second embodiment, no insulating member is required for each fuse  102 , with the result that the fuse module can be made lighter. Further, it is sufficient to provide areas where the terminal sections  104 ,  105  of the fuses  102  and the first connecting portions  111 ,  121  of the connection terminals  110 ,  120  can be in contact with each other, a multitude of connection terminals and a multitude of fuses can be arranged in a compact construction. Furthermore, since the fuses  102  are arrayed at specified intervals along direction Y substantially normal to the spaced-apart direction of the terminal sections  104 ,  105  at the opposite sides of the fuses  102 , the fuses and the connection terminals can be arranged at a high density. 
   In the second embodiment, the respective connection terminals  110 ,  120  to be connected with the terminal sections  104 ,  105  at the opposite sides of the fuses  102  are held in the casing main body  31  such that the first connecting portions  111 ,  121  thereof are arrayed along direction Y in which the fuses  102  are arrayed and located substantially on the same plane, i.e., substantially at the same height. Thus, the fuses  102  can be advantageously easily mounted, and the fuse module can be smaller since the fuses  102  are located substantially on the same plane. Since the spacing L 3  between the terminal sections  104  and  105  at the opposite ends of the fuses  102  is constant among the fuses  102  and the spacing L 4  (=L 3 ) between the first connecting portions  111  and  121  to be connected with the terminal sections  104  and  105  is constant, the fuses  102  having different fusing characteristics can be used at desired positions, i.e., it does not matter where the fuses  102  are used. Further, the connection terminals  110 ,  120  are arranged in the direction of the rows H, I, J while being separated into the input side and the output side and the fuses  102  are electrically connected between suitable input-side connection terminals  120  and the output-side connection terminals  110 . Since the connection terminals  110 ,  120  are orderly arrayed, maintenance can be easily made. Further, since the first connecting portions  121  of the input-side connection terminals ( 120   a ,  120   b ,  120   d ,  120   e ,  120   f ,  120   g ) extend in the direction of the rows H, I, J and are connected with the first connecting portions  111  of a plurality of output-side connection terminals  110  via the fuses  102 , assembling of the input-side connection terminals  120  can be easier and the number thereof can be reduced. As a result, the construction of external circuits (e.g., busbar circuits) can be made simpler. 
   Further, since the second connecting portions  122  all project down and the tab terminals  140  are externally connected with the second connecting portions  122  via the tab terminal insertion holes  138   a ,  138   b  formed in the fuse casing  130 , the fuse casing  130  having an internal circuitry in which the fuses  102  are connected with the connection terminals  110 ,  120  in a desired manner can be mounted into connection with the tab terminals  140  provided in the electrical connection box via the tab terminal insertion holes  138   a ,  138   b , and desired second connecting portions  112 ,  122  and desired tab terminals  140  are connected at once, thereby remarkably improving an operability of mounting the fuses in the electrical connection box. Furthermore, the respective connection terminals  110 ,  120  can be mounted by inserting the second connecting portions  112 ,  122  into the connecting portion mount holes  136   a ,  136   b  formed in the casing main body  131 . If one connecting portion mount hole  136   a  and one connecting portion mount  136   b  are formed in each recess  134  of the casing main body  131  as described above, the arrangement of the connection terminals  110 ,  120  and the used state of the connection terminals  120  having the first connecting portions  121  of various different lengths can be changed in a desired manner. Further, since the fuse casing  130  is comprised of the opening  131   a  and the cover  132  capable of detachably closing the opening  131   a , the connection terminals  110 ,  120  and the fuses  102  may be mounted in a desired manner through the opening  131   a  with the cover  132  detached and then the cover  132  may be put to close the opening  131   a . This leads to an improved operability. 
   Although the fuses  102  are arrayed in three rows H, I, J in the second embodiment, the present invention is not limited thereto. The fuses  102  may be arranged in one, two or more rows depending on the number thereof to be used. 
   Further, although the terminal sections of the fuses are mounted on the first connecting portions of the connection terminals mounted in the casing in the second embodiment, the present invention is not limited thereto. The connection terminals may be mounted later such that the terminal sections of the fuses placed at specified positions in the casing are covered by the first connecting portions. 
   Furthermore, the second connecting portions and the tab terminals are electrically connected with each other by inserting the tab terminals into the forked inserting portions provided at the second connecting portions in the second embodiment. However, according to the present invention, the forked inserting portions may be conversely formed at the tab terminals, and the second connecting portions and the tab terminals are electrically connected with each other by inserting the second connecting portions having no slit into the forked inserting portions. 
   The fuses themselves need not be insulated by the insulating members since a plurality of fuses are arranged inside the fuse casing. Thus, the fuse module can be made lighter by eliminating the need for the insulating members. Further, the opposite terminal sections need not be covered by the insulating member, and it is sufficient for the output terminal to have at least such a size as to be connectable with the tab terminal and for the input terminal to have at least such a size as to be connectable with the tab terminal and the shorting member. Thus, the terminal sections can be made smaller. As a result, the fuse module can be made smaller. 
   Further, since the entire fuse module is covered by the insulating fuse casing even when the connection terminals are used, it is not necessary to provide the insulating members for the respective fuses, thereby enabling the fuse module to be smaller. Further, it is sufficient to provide at least areas where the terminal sections of the fuses and the connecting portions of the connection terminals are in contact, a multitude of connection terminals and a multitude of fuses can be arranged in a compact construction. 
   As described above, an inventive fuse module comprises a plurality of fuses each having a fusing element and terminal sections at opposite ends of the fusing element, and a fuse casing for accommodating all of the plurality of fuses. The fuse casing is made of an insulating material, and formed with external terminal insertion holes. 
   One and the other of the terminal sections of each fuse accommodated in the fuse casing function as an input terminal and an output terminal, respectively. The respective output terminals are so arranged as to be electrically connectable with external terminals of busbars via external terminal insertion holes formed to penetrate the fuse casing from inside to outside. The respective input terminals are so arranged as to be electrically connectable with external terminals of the busbars via second external terminal insertion holes formed to penetrate the fuse casing from inside to outside. 
   Since a plurality of fuses are arranged inside the fuse casing in the inventive fuse module, it is not necessary to insulate the fuses themselves by insulating members and the fuse module can be made lighter by eliminating the use of the insulating members. Further, the input and output terminals of the respective fuses need not be covered by insulating members, and it is sufficient for the input terminals and the output terminals to have at least such sizes as to be connectable with the external terminals (tab terminals). Thus, the opposite terminal sections can be made smaller and, as a result, the fuse module can be made smaller. 
   Preferably, the respective fuses are plate-shaped and are vertically mounted in fuse mount holes individually provided therefor in a base portion of the fuse casing. 
   With this construction, since the fuses are individually mounted in the fuse mount holes formed in the insulating fuse casing, the respective fuses can be insulated from other fuses. Further, since the fuses are vertically mounted in the fuse mount holes, a mounting area can be made smaller, thereby enabling the fuse module to be even smaller. 
   Preferably, each fuse mount hole is formed such that a pair of terminal mounting portions in which the two terminal sections of the corresponding fuse are mounted and a fusing element mounting portion in which the fusing element of the corresponding fuse is mounted are horizontally aligned, and the width of the two terminal mounting portions is at least substantially equal to the thickness of the fuse. 
   With this construction, the fuses can be securely held without shaking at the terminal mounting portions located at the opposite ends of the fuses since the width of the opposite terminal mounting portions is substantially equal to the thickness of the fuses. 
   Preferably, spacing between the two terminal sections of each fuse is constant among the respective fuses. 
   With this construction, desired fuses can be mounted in the fuse mount holes and the fuses can be used without being chosen if their fuse capacities are same. 
   Preferably, the width of the fusing element mounting portions is larger than the thickness of the fuses. 
   With this construction, clearances are formed between the fusing element of each fuse mounted in the fuse mount hole and the fusing element mounting portion. Thus, the fuse can be easily taken out using these clearances. 
   Preferably, the input terminals are arrayed in the same row and an electrically conductive shorting member is further provided to simultaneously engage a plurality of input terminals. 
   With this construction, when the shorting member is engaged with the plurality of input terminals, the plurality of input terminals engaged are shorted with each other since the shorting member is electrically conductive. Thus, it is sufficient to connect at least one of the plurality of shorted input terminals with the tab terminal of the busbar, which leads to reduction in the number of the busbars and simplifies the construction of the busbars. Further, since the electrically conductive shorting member is engaged with the input terminals arrayed in the same row, the plurality of input terminals are simultaneously engaged and shorted, thereby improving an operability of mounting the shorting member. 
   Preferably, the shorting member includes a plurality of comb-shaped press-contact blades for engaging the plurality of input terminals while holding them from opposite sides. 
   With this construction, when the shorting member is so pushed that the respective input terminals are insertable into the comb-shaped press-contact blades, the respective comb-shaped press-contact blades and the respective input terminals are simultaneously engaged. Therefore, the input terminals can be shorted by a simple operation. 
   Preferably, the plurality of comb-shaped press-contact blades are provided at the same intervals. 
   With this construction, since the comb-shaped press-contact blades are provided at the same intervals in the shorting member, the shorting member can be used without choosing the input terminals to be shorted by arranging the input terminals at intervals in conformity with the arrangement intervals of the comb-shaped press-contact blades. 
   Preferably, the input terminals are arranged to face the outer side of the fuse casing, and the shorting member is inserted into the fuse casing from outside. 
   With this construction, since the shorting member is inserted into the fuse casing from outside, it is not necessary to provide the shorting member in a narrow space within the fuse casing and a shorting operation by the shorting member can be made easier. 
   Another inventive fuse module comprises a plurality of fuses each having a fusing element and terminal sections at opposite ends of the fusing element, a plurality of connection terminals including first connecting portions to be connected with the respective terminal sections and second connecting portions to be connected with external terminals, and an insulating fuse casing for accommodating all of the fuses. The insulating fuse casing is formed with a plurality of connection terminal holding portions for holding the plurality of connection terminals in a state that at least the first connecting portions are exposed. The terminal sections of the fuses are connected with the exposed first connecting portions. The second connecting portions are so arranged as to be electrically connectable with external terminals of busbars via external terminal insertion holes formed to penetrate the fuse casing from inside to outside. 
   Since the inventive fuse module is covered in the entirety by the insulating fuse casing, it is not necessary to provide an insulating member for each fuse, which enables the fuse module to be lighter. Further, since it is sufficient to provide at least areas where the terminal sections of the fuses and the connecting portions of the connection terminals are in contact, a multitude of connection terminals and a multitude of fuses can be arranged in a compact construction. 
   Preferably, the respective fuses are arrayed at specified intervals in a row direction substantially normal to a spaced-apart direction of the terminal sections at the opposite sides of the respective fuses. 
   With this construction, the fuses and the connection terminals can be arranged at a high density. 
   Preferably, the respective connection terminals to be connected with the terminal sections at the opposite sides of the fuses are held in the fuse casing such that the first connecting portions thereof are arrayed in the row direction in which the fuses are arrayed, and are located substantially on the same plane. 
   With this construction, since the first connecting portions are arrayed in the specified direction and at the same height, there is an advantage that the fuses can be easily mounted. In addition, since the fuses are located substantially on the same plane, the fuse module can be made smaller. 
   Preferably, spacing between the terminal sections at the opposite sides of each fuse is set equal among the respective fuses and spacing between the first connecting portions to be connected with the opposite terminal sections is also set equal. 
   With this construction, fuses having different fusing characteristics can be used at desired positions; it does not matter at which positions the fuses are used. 
   Preferably, the connection terminals are arrayed in the row direction while being separated into an input side and an output side, and each fuse is electrically connected between a suitable input-side connection terminal and a suitable output-side connection terminal. 
   With this construction, maintenance can be easily made since the connection terminals are orderly arrayed. 
   Preferably, the first connecting portions of at least part of the input-side connection terminals extend in the row direction and are connected with the first connecting portions of a plurality of output-side connection terminals via the fuses. 
   With this construction, since the number of the input-side connection terminals can be reduced, the assembling of the input-side connection terminals can be easier and the number thereof can be reduced, and the construction of external circuits (e.g., busbar circuits) can be made simpler. 
   Preferably, all the second connecting portions project in the same direction. With such second connecting portions, the external circuits can be connected with the respective connection terminals in one direction. More specifically, the external terminals are preferably connected with the second connecting portions from outside via external terminal insertion holes formed in the fuse casing. 
   With this construction, when the fuse casing having an internal circuitry in which the fuses are connected with the connection terminals in a desired manner is mounted into connection with the external terminals such as tab terminals provided in an electrical connection box via the external terminal insertion holes, all the second connecting portions and external terminals are connected at once. Contrary to this, in the case of a conventional structure for mounting fuses into an electrical connection box, the fuses need to be mounted one by one into connection with a multitude of tab terminals provided in a fuse mounting section of the electrical connection box by insertion, leading to a poor fuse mounting operability. However, the inventive construction can remarkably improve an operability of mounting the fuses into the electrical connection box. 
   Further, in the inventive fuse module, the respective connection terminals may be mounted by inserting the second connecting portions into connecting portion mount holes formed in the fuse casing. 
   With this construction, the connecting portion mount holes are formed in the fuse casing beforehand, and the connection terminals can be mounted later on by inserting the second connecting portions into the connecting portion mount holes. If the connecting portion mount holes are provided at many positions, the arrangement of the connection terminals and the used state of the connection terminals having the first connecting portions of various different lengths can be changed in a desired manner. 
   Preferably, the fuse casing includes an opening through which the connection terminals and the fuses are mounted, and a cover detachably mountable to close the opening. 
   With this construction, the connection terminals and the fuses may be mounted through the opening with the cover detached and then the cover may be put to close the opening. This leads to a good operability. 
   This application is based on patent application No. 2000-382673 and 2001-3340 filed in Japan, the contents of which are hereby incorporated by references. 
   As this invention may be embodied in several forms without departing from the spirit of essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within metes and bounds of the claims, or equivalence of such metes and bounds are therefore intended to embraced by the claims.