Patent Document

BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to a connection box which collectively connects and distributes wire-harness in the case that wire harness is arranged in a vehicle.  
           [0002]    The connection box is substantially formed by piling a single-layered or a multi-layered circuit board in which bus bar and electric wires are arranged so as to constitute a desired circuit, on a plane wiring board, and by covering the board by an upper cover and an under cover. A control boardboard constituting an electronic control portion is mounted on the board mentioned above. The control base boardboard has an insulating board, and electronic parts such as a resistor, a coil, a relay, a fuse and the like are provided thereon. The control base board is connected to a predetermined circuit of the board.  
           [0003]    The relay provided on the control base board could employ a mechanical type using an electromagnetic solenoid in order to be capable of accommodating to a comparatively large electric current. The mechanical relay has an electromagnetic solenoid to produce a large amount of heat.  
         SUMMARY OF THE INVENTION  
         [0004]    However, in the connection box mentioned above, the relay is generally mounted to the insulating board in the same closely contact manner as that of the other electronic parts. Accordingly, heat to be produced by the relay has a great influence on the insulating board. This heat gives an influence onto the other electronic parts so as to cause a false function.  
           [0005]    Accordingly, the present invention provides a connection box, which effectively reduces the influence of produced heat of a relay against another electronic part by a simple structure of changing a mounting state of the relay, thereby improving a reliability.  
           [0006]    The aspect of the invention provides a connection box. The box includes a circuit board. The box includes a control board connected to the circuit board. The control board includes an insulation board. The box includes a radiative device mounted on the control board. The radiative device is spaced away from the insulation board.  
           [0007]    Preferably, the radiative device includes a wire extending therefrom above the insulation board.  
           [0008]    Preferably, the radiative device includes a relay.  
           [0009]    According to the invention, the radiative device and the insulation board have an air layer with a spacing between them. The air layer works as a heat insulation layer to insulate the heat produced from the radiative device. This insulation reduces the heating of the insulation board. This results in restricting of heat influence applied to the other electronic parts mounted to the insulation board.  
           [0010]    The wire exposes from the radiative device, and a part of the heat produces in the radiative device is conducted to the wire. The radiating of heat at an exposure portion allows the radiative device to be cooled. 
       
    
    
     BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS  
       [0011]    [0011]FIG. 1 is an exploded perspective view of a module;  
         [0012]    [0012]FIG. 2 is a perspective view of the module;  
         [0013]    [0013]FIG. 3 is a plan view of the module;  
         [0014]    [0014]FIG. 4 is an enlarged perspective view of a basic structure from which various kinds of electronic parts of a control base board have been removed;  
         [0015]    [0015]FIG. 5 is a plan view showing a cross section of a compression bonded portion of a compression bonded terminal in which the control base board has been mounted to a plane wiring board;  
         [0016]    [0016]FIG. 6 is an enlarged perspective view of a base board connector;  
         [0017]    [0017]FIG. 7 is an enlarged sectional view of a main portion taken along a line of VII-VII in FIG. 2;  
         [0018]    [0018]FIG. 8 is an enlarged sectional view of a main portion taken along a line of VIII-VIII in FIG. 5;  
         [0019]    [0019]FIG. 9 is a sectional view taken along a line IX-IX in FIG. 3;  
         [0020]    [0020]FIG. 10 is a sectional view of a main portion showing a connection structure between the insulation displacing terminal and a circuit pattern in the control base board;  
         [0021]    [0021]FIG. 11 is a schematic view of electric wires arranged on the plane wiring board; and  
         [0022]    [0022]FIG. 12 is a perspective view in which the module and a case in an electric connection box have been separated. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0023]    A description will be in detail given below of an embodiment according to the present invention with reference to the accompanying drawings.  
         [0024]    A connection box  10  has a plane wiring board  12  in which multi-layered circuit boards  12   a ,  12   b  and  12   c  are piled, as shown in FIG. 1. A control base board  15  is mounted on the board  12 . The base board  15  is received between an upper cover  11  and an under cover  13 . They constitute a module  14  as shown in FIG. 2. The module  14  is received within a case  18  constituted by an upper case  16  and a lower case  17 .  
         [0025]    Side walls  11   a   1  and  11   a   2  around the upper cover  11  are removably fitted to outer surfaces of upper end portions in side walls  13   a   1  and  13   a   2  around the under cover  13  via a lock hook  13   b . The cover  11  receives the board and the base board  15  in an inner side thereof.  
         [0026]    The upper surface (on the drawing) of the upper cover  11  forms a mounting face E, and various kinds of relays such as a micro relay  20 , a half micro relay  21 , a 2M relay  22  and the like which are outward attached, and outward attached electronic parts such as a fuse and the like are mounted thereto, as shown in FIGS. 1, 2 and  3 . This mounting face E has insertion openings  11   b ,  11   c  and  11   d  for the various kinds of relays. The mounting face E has an insertion opening lie for the fuse  23 .  
         [0027]    One side (a left end portion in FIG. 3) of the upper cover  3  is provided with a plurality of connectors  11   f  for removably inserting mating connectors (not shown) in a combined manner.  
         [0028]    Further, as shown in FIG. 2, the upper cover  11  and the under cover  13  have both side walls  11   a   2  and  13   a   2  in a Y direction. First pressing lock pieces  11   g  and  13   c  having an L-shaped cross section are integrally protruded from the side walls  11   a   2  and  13   a   2  respectively. Second pressing lock pieces  13   d  having an L-shaped cross section are integrally protruded from both side walls  11   a   1  and  13   a   1  in an X direction orthogonal to the side walls  11   a   2  and  13   a   2 .  
         [0029]    The plane wiring board  12  is formed by a rectangular reverse-dish-shaped hard resin board as shown in FIG. 1, and is formed together with a lot of wiring holes  12   d . The board  12  has three plied circuit boards  12   a ,  12   b  and  12   c  thereon. The board  12  has a plurality of arranged electric wires  56  on a back surface thereof.  
         [0030]    The respective circuit boards  12   a ,  12   b  and  12   c  have bus bars respectively arranged thereon, and the bus bars constitute a desired circuit. The bus bars respectively have terminal portions  30 ,  31  and  32 , and they are stood upward from predetermined positions. Each of the respective circuit boards  12   a ,  12   b  and  12   c  has an insulation displacing terminal  57 , which is integrally formed with the bus bar and is stood downward from a predetermined position.  
         [0031]    The respective circuit boards  12   a ,  12   b  and  12   c  are stacked with each other. The lower circuit board  12   c  has a terminal  32 , which passes through the upper circuit boards  12   a  and  12   b  so as to protrude above of the upper circuit board  12   a . The middle circuit board  12   b  has a terminal  31 , which passes through the upper circuit board  12  so as to protrude out. The insulation displacing terminals  57  of the respective circuit boards  12   a ,  12   b  and  12   c  are taken out to the back surface of the board  12  from the wiring holes  12   d , and are press contacted to electric wires  56  so as to be connected as shown in FIG. 8. Accordingly, the board  12  has a desired circuit constituted by the respective circuit boards  12   a ,  12   b  and  12   c  and the electric wires  56 .  
         [0032]    The control base board  15  has an insulation board  15   a , and various kinds of electronic parts, for example, a relay  40 , a resistor  41 , a coil  42  and a control device  43  are mounted thereto. The base board has a connector  44  at an end portion in a longitudinal direction thereof. The control base board  15  is arranged in a standing state. A terminal block  50  is mounted in a substantially perpendicular direction to a front surface (in a near side in the drawing) of a lower end portion in the base board  15 , as shown in FIG. 4. A desired number of insulation displacing terminals  51  connected to a predetermined circuit of the base board  15  protrude from a vertical outer surface  50   a  (a lower surface in the drawing) of the terminal block  50 .  
         [0033]    The electronic parts have a power portion P constituted by the relay  40 , the resistor  41  and the coil  42 . The electronic parts have a control portion C constituted by a device (for example, a microprocessor, ROM or RAM)  43 . As shown in FIG. 5, the power portion P having a large amount of generation heat is arranged in a half side (in a near side in FIG. 1) in a longitudinal direction of the insulation board  15   a  together. The control portion C having a small amount of generation heat is arranged in another half side (in a far side in FIG. 1) in the longitudinal direction of the insulation board  15   a  together.  
         [0034]    The relay  40 , the resistor  41  and the coil  42  in the power portion P, and the device  43  in the control portion C are connected by a narrow circuit pattern  46  (refer to FIG. 10). The circuit pattern  46  is structured such that a conductor is printed on the insulation board  15   a . A width of the print determines whether the circuit pattern  46  is thick or narrow.  
         [0035]    The connector  44  is independently provided from the base board  15 , as shown in FIG. 6. The mating connector (not shown) is inserted to an insertion opening  44   a  thereof. The end of each of a plurality of terminals  44   b  protrudes within the insertion opening  44   a . This one end is connected to the mating connector. Another end of each of these terminals  44   b  protrudes to an outer portion corresponding to a lower side in the drawing of the insertion opening  44   a . A front end of another end is bent perpendicular to the base board  15 .  
         [0036]    The connector  44  has a projection  44   c  on a rear side, as shown in FIG. 7. The projection  44   c  is pressed into a fitting hole (not shown) formed in the insulation board  15   a  of the base board  15 . According to this pressing, the front end of the terminal  44   b  is inserted to the control base board  15  and is connected to a predetermined circuit pattern. At this time, the insertion opening  44   a  of the connector  44  is faced outward from an opening  11   h  formed in the upper cover  11 .  
         [0037]    The relay  40  employs a mechanical type using an electromagnetic solenoid. The relay is structured such as to be turned on and off by the electromagnetic solenoid. This structure increases generation heat of the solenoid. Accordingly, the relay  40  is supported to a relay holding board  45  mentioned below, as shown in FIG. 8. The relay is mounted by a predetermined spacing δ apart from the insulation board  15   a  of the base board  15 .  
         [0038]    The relay  40  has power terminals  40   a  and  40   b , and they are respectively connected to a terminal  51  mentioned below and a lead wire  40   c . The lead wire  40   c  extends from the relay  40  to the insulation board  15   a . The lead wire  40   c  extends long and in parallel to the insulation board  15   a  therebetween. The extension exposes the lead wire  40   c  on the insulation board  15   a . The exposed front end portion is bent to the insulation board  15   a  and is fixed to the circuit pattern  46  by a solder  47   a . The exposed lead wire  40   c  is provided with a heat radiating function.  
         [0039]    The terminal block  50  is separated into two pieces in a substantially center portion in a longitudinal direction thereof, so as to constitute a first separation block  50   b  and a second separation block  50   c . End portions in the first and second separation blocks  50   b  and  50   c  which are adjacent to each other are stacked with each other as shown in FIG. 4, so as to constitute a stacked part  52 . The both end portions and the stacked part  52  are fastened to the board  12  by a screw  53  corresponding to a fastening member, as shown in FIG. 9, thereby fixing the terminal block  50 . The screw  53  is inserted from the back surface of the board  12 . The stacked part  52  is fastened by one screw  53  as shown in FIG. 5.  
         [0040]    The first separation block  50   b  has a vertical inner surface  50   d , and the relay holding board  45  is provided therein in parallel to the insulation board  15   a , as shown in FIG. 5. The holding board  45  has a window portion  45   a  in correspondence to the arrangement of the relay  40 . By fitting the relay  40  to the window portion  45   a  so as to retain, it is possible to stably retain the relay  40  which is apart from the insulation board  15   a.    
         [0041]    The end of the terminal  51  protrudes from the vertical outer surface  50   a  of the terminal block  50 . Another end thereof has a conduct wire part  54  protruding out from the upper side of the terminal block  50 . The conduct wire part  54  is perpendicularly bent toward the insulation board  14   a  of the control base board  15  so as to pass through the insulation board  15   a . As shown in FIG. 10, the through portion is fixed to the circuit pattern  46  of the control base board  15  by a solder  47 .  
         [0042]    Further, the terminal  51  is connected to the relay  40  mentioned above, and as shown in FIG. 8, another end thereof passes through the holding portion  45  so as to protrude within the window portion  45   a.    
         [0043]    The terminal  51  is inserted from an insertion opening  55  of the board  12 , as shown in FIG. 1. The terminal  51  is press contacted to a terminal of the electric wire  56  so as to be connected, as shown in FIG. 5.  
         [0044]    At this time, the outer surface  50   a  of the terminal block  50  contacts with the upper surface of the board  12 . In this state, the outer surface  50   a  is fastened and fixed by the screw  53 . In a state of fixing the terminal block  50  to the board  12 , the terminal block  50  is substantially perpendicular to the insulation board  15   a . Accordingly, the base board  15  is perpendicularly mounted to the board  12 .  
         [0045]    The upper cover  11  has the mounting face E, as shown in FIGS. 1 and 2, and the control base board  15  is arranged in a half side (a far side part in FIGS. 1 and 2) thereof. This one half side forms the insertion openings  11   b ,  11   c  and  11   d , various kinds of relays  20 ,  21  and  22 , and a bulge  60 . The relays  20 ,  21  and  22  are outward mounted to the insertion opening  11   e . In the bulge  60 , a protruding amount h becomes larger than that of the fuse  23 . As shown in FIG. 9, the bulge  60  receives the control base board  15  in an inner side thereof.  
         [0046]    The bulge  60  has a heat insulation wall  60   a  as shown in FIG. 9. The wall  60   a  insulates thermally the base board  15  from the respective insertion openings  11   b ,  11   c  and  11   d  of the upper cover  11 . The bulge  60  has a top wall  60   b  continuously provided from the wall  60   a . The bulge  60  has a rear wall  60   c  covering a back side of the control base board  15 . The walls  60   a ,  60   b  and  60   c  are formed so as to have a C-shaped cross section. As shown in FIG. 2, the bulge  60  has both ends, and they are closed by side walls  60   d.    
         [0047]    Further, the control base board  15  has the power portion P and the control portion C, as shown in FIG. 5, and they are separately arranged. The bulge  60  has a heat insulation partition  60   e  in an inner side thereof as shown in FIG. 9, and this is inserted between the power portion P and the control portion C. The partition  60   e  insulates the power portion P and the control portion C. The partition  60   e  is shown by a two-dotted chain line in FIG. 5.  
         [0048]    Accordingly, in a state of receiving the base board  15  between the upper cover  11  and the under cover  13 , the bulge  60  covers an outer side of the base board  15 . The partition  60   e  is inserted into a boundary between the portion having a great amount of generation heat and the portion having a small amount of generation heat in the base board  15 .  
         [0049]    The case  18  has the upper case  16  and the lower case  17  constituting a pair, as shown in FIG. 12. A side wall  16   a  of the upper case  16  is mated to an outer peripheral surface of a side wall  17   a  of the lower case  17 . A lock hook  16   b  of the upper case  16  is removably engaged with an engagement projection  17   b  of the lower case  17 .  
         [0050]    The upper case  16  and the lower case  17  define openings  16   c  and  17   c  respectively notched at positions corresponding to the connector insertion openings  11   f  and the base board connector  44 . These openings  16   c  and  17   c  form one opening portion  18   a  at a time of mating the upper case  16  and the lower case  17  with each other.  
         [0051]    The openings  16   c  and  17   c  have a closing member  61  therebetween, and this is independent from the upper case  16  and the lower case  17 . The closing member  61  closes a portion between the openings  16   c  and  17   c  at a time of mating the upper case  16  to the lower case  17 . The closing member  61  has a lock hook  61   a , and this is fixed removably to an engagement projection  17   d  of the lower case  17 .  
         [0052]    At this time, an upward-directed semi-cylinder portion  17   e  is formed in a lower part of the opening portion  17   c . A downward-directed semi-cylinder portion  61   b  is formed in a lower part of the closing member  61 . The semi-cylinder portions  17   e  and  61   b  are combined so as to form a cylindrical shape. The cylinder portion passes wire harnesses of the mating connectors (not shown) connected to the connector  11   f  and the base board connector  44  through in a lump. A mounting leg  17   f  is perpendicularly provided in the lower case  17 .  
         [0053]    At a time of receiving the module  14  in the case  18 , the module  14  is at first received in the lower case  17  and the bulge  60  is arranged in the above, as shown in FIG. 12. The upper case  16  is mated to the outer peripheral surface of the lower case  17  from the above. According to this mating, the hook  16   b  and the projection  17   b  are engaged. The mating connector is connected to the connector  11   f  and the connector  44  in the module  14  from the opening  18   a . The wire harness is arranged between both of the semi-cylinder portions  61   b  and  17   e . The closing member  61  is arranged in the opening portion  18   a . The hook  61   a  is engaged with the projection  17   d.    
         [0054]    At a time of inserting the module  14  into the case  18  from the above so as to receive therein, the first pressing lock pieces  11   g  and  13   c  of both of the side walls  11   a   2  and  13   a   2  in a Y direction (refer to FIG. 2) are engaged with engagement portions (not shown) in an inner side of the lower case  17 . Front end surfaces of the first lock pieces  11   g  and  13   c  resiliently abut against the inner side of the lower case  17 . This abutment prevents the module  14  from loosening within the case  18 .  
         [0055]    Further, when case  18  receives module  14 , the mounting face E of the upper cover  11  is arranged in a front surface  17   g  of the lower case  17 . At this time, the insertion opening  11   e  of the mounting face E is positioned at a right half portion (shown by a two-dotted chain line in the drawing) of an upper end portion in the front surface  17   g  of the lower case  17 . According to the present embodiment, the right half portion of the upper end portion is previously cut, and an opening  17   h  to which the insertion opening  11   e  is exposed is formed.  
         [0056]    Next, a description will be given of an operation.  
         [0057]    In the connection box  10  mentioned above, the base board  15  corresponding to the control portion is mounted to the board  12 . The module  14  is structured by receiving the board  12  between the upper cover  11  and the under cover  13 . The connection box  10  is structured by receiving the module  14  within the case  18  constituted by the upper case  16  and the lower case  17 . The lower case  17  of the connection box  10  is mounted within an engine room of a vehicle (not shown) via the mounting leg  17   f . The connection box  10  is collectively connected to the wire harnesses (not shown) of the various kinds of electrical equipment provided in the vehicle.  
         [0058]    In this connection box  10 , the relay  40  to be provided in the base board  15  is mounted by a predetermined spacing δ apart from the surface of the insulation board  15   a , as shown in FIG. 8. The relay  40  and the insulation board  15   a  have an air layer corresponding to the spacing δ between. The air layer forms a heat insulation layer so as to insulate the heat produced by the relay  40 . This insulation reduces the heating of the insulation board  15   a . This results in restricting a heat influence applied to the other electronic parts mounted to the insulation board  15   a , in particular, the device  43  constituting the control circuit, in the connection box  10 .  
         [0059]    According to the reduction of the heat influence applied to the device  43 , it is possible to prevent the device  43  from being broken and it is possible to prevent the false function from occurrence. Due to this prevention, it is possible to execute a stable and aimed control and it is possible to increase a reliability of the connection box  10 . It is possible to secure a stability of the relay  40  by mounting the relay  40  to the inner surface  50   d  of the terminal block  50 . In the case of mounting the relay  40  to the terminal block  50 , it is also possible to prevent the heat generation of the relay  40  from being directly conducted to the insulation board  15   a  of the base board  15 .  
         [0060]    Since the long lead wire  40   c  exposes from the relay  40 , a part of the heat to be produced in the relay  40  is conducted to the lead wire  40   c . It is possible to effectively cool the relay  40  itself by radiating the heat by the exposure portion. Accordingly, according to the heat radiation in the lead wire  40   c , it is possible to reduce the generation heat contained in the relay  40  and the heat conducted from the relay  40  to the insulation board  15   a . This reduction further reduces the heat influence on the other electronic parts.  
         [0061]    The entire contents of Japanese Patent Applications P2001-133531 (filed on Apr. 27, 2001) are incorporated herein by reference.  
         [0062]    Although the invention has been described above by reference to certain embodiments of the invention, the invention is not limited to the embodiments described above. Modifications and variations of the embodiments described above will occur to those skilled in the art, in light of the above teachings. The scope of the invention is defined with reference to the following claims.

Technology Category: 5