Electrical junction box and wiring harness

Abstract

Electrical junction box (100) comprising: a can main body (101) fixed to a vehicle body and comprising a first housing (103) in which an electronic component (102) is mounted, and a second housing (105) installed on a vertically lower side of the first housing (103) with a locking mechanism, wherein the second housing (105) comprises: a frame (10) comprising the locking mechanism (106) on an outer side surface (10a) of the frame (10), a floor (20) arranged parallel to a panel (111) of the vehicle body, the panel (111) facing the floor (20) and covering a vertically lower end part of the frame (10), an inlet (30) provided on an outer surface of the second housing (105) and having a minimum distance from the panel (111), and a channel-forming recess (40) provided vertically below the inlet (30), formed by bending at least a part of the bottom (20) into the interior of the second casing (105), and formed along a surface of the panel (111) which gradually inclines toward the vertically lower side as the surface extends in one direction, to allow a liquid having entered between the bottom (20) and the panel (111) to flow outward from between the bottom (20) and the panel (111).

Description

BACKGROUND OF THE INVENTION1. Field of the InventionThe present invention relates to an electrical connection box and a wire harness.2. Prior ArtA vehicle such as a car includes an electrical connection box that distributes power from a power source such as a battery to electronic devices. Such an electrical connection box is, for example, an electrical connection box disposed in an engine room or other area into which a liquid such as water enters from the outside. An electrical connection box provided in an engine room or other area has various electronic components mounted thereon, and includes a box main body including a plurality of housings, wherein the outline of the box main body is formed along a surface of a panel of the engine room.For example, in an electrical connection box described in Japanese Patent Application Laid-Open No. 2005-185031, when the clearance between the outer surface of a box main body and the surface of a panel is small, liquid that has entered an engine room or another region may accumulate in the clearance between the outer surface of the box main body and the surface of the panel and enter inward through a joint between the housings.An electrical connection box in which a cover is attached to a housing on the lower side is known from U.S. Pat. No. 8,941,009 B2.SUMMARY OF THE INVENTIONIn view of the above-described circumstances, an object of the present invention is to provide an electrical connection box and a wire harness that can prevent liquid from entering a box main body having a plurality of housings contained therein.To achieve the above object, there is provided an electrical connection box according to claim 1. According to an aspect of the present invention, an electrical connection box includes a box main body fixed to a vehicle body and including a first housing in which an electronic component is mounted and a second housing installed on a vertically lower side of the first housing with a locking mechanism, the second housing including: a frame including the locking mechanism on an outer surface of the frame; a floor disposed parallel to a panel of the vehicle body, the panel facing the floor and covering a vertically lower end part of the frame; an inlet provided on an outer surface of the second housing and having a smallest distance from the panel; and a channel forming recess provided vertically below the inlet is formed by bending at least a part of the bottom inside the second housing and formed along a surface of the panel gradually inclined toward the vertically lower side the further the surface extends in a direction to allow liquid entered between the bottom and the panel to flow outward from between the bottom and the panel.Further, in the electrical connection box according to another aspect of the present invention, it is possible to configure such that the width of the channel-forming recess becomes gradually larger as the channel-forming recess extends along the surface of the panel toward the vertically lower side.Further, in the electrical connection box according to another aspect of the present invention, it is possible to provide such a configuration that a part of the lock mechanism serves as an inlet.In order to achieve the above object, a wire harness according to another aspect of the present invention includes an electrical connection box including a box main body fixed to a vehicle body and including a first housing in which an electronic component is mounted and a second housing installed at a vertically lower side of the first housing with a locking mechanism; and an electric wire electrically connected to the electronic component, the second housing including: a frame including the locking mechanism at an outer side surface of the frame; a floor disposed parallel to a panel of the vehicle body, the panel facing the floor, and covering a vertically lower end part of the frame; an inlet provided at an outer surface of the second housing and having a smallest distance from the panel; and a channel forming recess provided vertically below the inlet is formed by bending at least a part of the bottom inside the second housing and formed along a surface of the panel gradually inclined toward the vertically lower side the further the surface extends in a direction to allow liquid entered between the bottom and the panel to flow outward from between the bottom and the panel.These and other objects, features and advantages, as well as the technical and industrial significance of the invention, will be apparent from the following detailed description of presently preferred embodiments of the invention with reference to the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a perspective view schematically showing a configuration of an electrical connection box according to an embodiment of the present invention. FIG. 2 is a rear view of the electrical connection box according to the embodiment as viewed from the direction of arrow II of FIG. 1. FIG. 3 is a perspective view of the electrical connection box according to the embodiment as viewed from below. FIG. 4 is a plan view showing principal parts of the electrical connection box according to the embodiment in the assembled state with the upper cover removed. FIG. 5 is a sectional view taken along line V-V of FIG. 4. FIG. 6 is a sectional view taken along line VI-VI of FIG. 4, which is a sectional view of a positioning member or the like.DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSHereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. However, the scope of the invention is not limited to this embodiment. The components described for the following embodiment include those that can be easily replaced by those skilled in the art or are substantially identical.EmbodimentFIG. 1 is a perspective view schematically showing a configuration of an electrical connection box according to an embodiment of the present invention. FIG. 2 is a rear view of the electrical connection box according to the embodiment in the direction of arrow II of FIG. 1, FIG. 3 is a perspective view of the electrical connection box according to the embodiment as viewed from below. FIG. 4 is a plan view showing principal parts of the electrical connection box according to the embodiment in the assembled state with the upper cover removed. FIG. 5 is a sectional view taken along line V-V of FIG. 4, FIG. 6 is a sectional view taken along line VI-VI of FIG. 4, FIG. 1 illustrates electronic components in the electrical connection box by dotted lines.An electrical connection box 100 according to the embodiment shown in FIG. 1 is installed in a vehicle such as a car, and distributes, by various electronic components 102 or other components, a power supplied from a power source such as a battery to various electronic devices in the vehicle. The electrical connection box 100 is coupled to a wire harness 150 as shown in FIG. 1, and accommodates various electrical elements such as connectors, fuses, relays, branches, and electronic control units as parts for connection processing such as electric wires 151 or other parts. The electrical connection box 100 is disposed in an engine room of the vehicle, for example, and is connected between the power source such as a battery and the various electronic devices provided in the vehicle. In the embodiment, the electronic junction box 100 is disposed within an outer panel 110 (shown in FIG. 6 ) exposed to the exterior of the vehicle and adjacent to the outer panel 110. Moreover, in the embodiment, the electrical connection box 100 is disposed on the vertically upper side of a panel 111 (shown in FIG. 6 ) of a vehicle body, which panel is a part of the engine room. The electrical connection box 100 can also be referred to as a junction box, a fuse box or a relay box. However, in the embodiment, these various alternatives are collectively referred to as an electrical connection box.In the electrical connection box 100 of FIG. 1, the various electronic components 102 are accommodated in a housing space in a box main body 101. The can main body 101 includes, for example, as shown in FIGS. 1, 2, and 3, a body 103 (corresponding to a first housing), an upper cover 104, and a lower cover 105 (corresponding to a second housing). The can main body 101 has a three-layered structure divided into the body 103, the top cover 104, and the bottom cover 105. The body 103, the upper cover 104, and the lower cover 105 are formed of an insulating resin. The body 103 is the main member that forms the housing space in which the electronic components 102 are mounted. The body 103 is formed in a substantially tubular square shape and has openings at the vertically upper and lower sides of the electrical connection box 100 connected to the engine room, for example. The upper cover 104 is a lid-like member covering the opening on the vertically upper side of the body 103. The lower cover 105 is a dish-like (tray-like) member installed on the body 103 and covering the opening on the vertically lower side of the body 103. In the can main body 101, the upper cover 104 is installed on the vertically upper side of the body 103, and the lower cover 105 is installed on the vertically lower side of the body 103 such that the opening on the vertically upper side of the body 103 faces the opening of the upper cover 104 and the opening on the vertically lower side of the body 103 faces the opening of the lower cover 105. In the can main body 101, the upper cover 104 and the lower cover 105 are locked to the body 103 by various types of locking mechanisms 106. The stacking direction of the body 103, the upper cover 104, and the lower cover 105 is usually the vertical direction when the electrical connection box 100 is disposed in the engine room. However, depending on the installation state of the electrical connection box 100, the individual members may be stacked at a certain angle to the vertical direction.The various electronic components 102 mounted in the housing space inside the can main body 101 include, for example, connectors, fuses, relays, branches, and electronic control units as described above. In the electrical connection box 100, as shown in FIG. 4, the various electronic components 102 are mounted in a large number of cavities formed by, for example, a partition wall 107 of any shape integrally formed with the body 103 and a block 108 of any shape removably attached to the body 103. In this case, the partition wall 107 and the block 108, for example, as well as the body 103 and the other parts, are formed of an insulating resin. In the electrical connection box 100, terminals or the like of the electric wires 151 are fitted from the vertically lower side and electrically connected to the cavities in which the various electronic components 102 are mounted. The electric wires 151 are passed through an opening 109 or the like and connected to the electronic components 102. The electrical connection box 100 configured as described above is installed in the vehicle using fixing brackets 112 fixed to the panel 111, for example. The fixing brackets 112 are provided on the body 103 and the lower cover 105 of the can main body 101. The electrical connection box 100 and, for example, the electric wires 151 electrically connected to the electronic components 102 constitute the wire harness 150 carried in a vehicle such as a car. In other words, the wire harness 150 includes the electrical connection box 100 and the electric wires 151 electrically connected to the electronic components 102 in the electrical connection box 100.Hereinafter, the vertical direction, the vertically lower end part, the vertically upper end part, the vertically upper side, and the vertically lower side in the present specification are respectively the vertical direction, the vertically lower end part, the vertically upper end part, the vertically upper side, and the vertically lower side of the electrical connection box 100 fixed to the panel 111 and installed in the vehicle.The lower cover 105 contained in the can main body 101 is a dish-like (tray-like) member that covers the opening at the vertically lower side of the body 103 as shown in FIGS. 2 and 3. The lower cover 105 includes a rectangular frame 10 (corresponding to a frame) formed in a substantially square shape, and a bottom 20 covering the opening at the vertically lower side of the rectangular frame 10. The rectangular frame 10 includes, at the vertically upper end part of an outer side surface 10 a, the locking mechanism 106 used for locking the lower cover 105 to the body 103. The floor 20 faces the panel 111 at the vertically lower side of the floor 20. The bottom 20 is formed in a flat plate shape and is disposed parallel to the facing panel 111.The lower cover 105 thus configured is disposed such that the outer side surface 10 aof the rectangular frame 10 and the bottom 20 are parallel to the panel 111 when the electrical connection box 100 is fixed to the panel 111. The lower cover 105 is disposed such that the outer side surface 10 aof the rectangular frame 10 and the bottom 20 are close to the panel 111. The distance from the panel 111 to the outer side surface 10 aof the rectangular frame 10 and the bottom 20 of the undercover 105 is about 5 mm, for example.As shown in FIG. 5, the undercover 105 includes, on its outer surface, an inlet 30 that is the smallest distance from the panel 111 and allows liquid that has entered the engine compartment to pass between the inlet 30 and the panel 111. In the embodiment, the inlet 30 is a vertically lower end part 106 awhich is a part of one of the lock mechanisms 106 formed on the vertically upper end part of the outer side surface 10 a. Note that the distance from the panel 111 described herein is the smallest distance among the distances from the panel 111 to positions on the outer surface of the undercover 105.In the embodiment, as shown in FIG. 5, the lower cover 105 includes a channel-forming recess 40 provided vertically below the inlet 30. The channel-forming recess 40 allows liquid that has entered between the bottom 20 of the lower cover 105 and the panel 111 through the inlet 30 to flow outward between the bottom 20 and the panel 111. The channel forming groove 40 forms between itself and a surface of the panel 111 vertically facing it a channel R (a space surrounded by the alternate long and two short dash lines in FIGS. 2, 3 and 4 ) allowing the liquid to flow outward. Note that the exterior in the present description is to be understood as the area outside the space between the floor 20 and the panel 111.Specifically, as seen in a cross-sectional view, the channel-forming recess 40 is formed by a part of the rectangular frame 10 and a part of the bottom 20, these parts being bent into the inside of the lower cover 105 so that the distance from the panel 111 to the channel-forming recess 40 is larger than that from the panel 111 to the inlet 30, i.e., the vertically lower end part 106 aof the locking mechanism 106. In the embodiment, the channel-forming recess 40 is formed at a boundary between the rectangular frame 10 and the bottom 20. The distance from the panel 111 to a part of the floor 20 vertically below the channel-forming recess 40 is smaller than the distance from the panel 111 to the channel-forming recess 40.The channel forming groove 40 is linearly formed along the surface of the panel 111 gradually inclining toward the vertically lower side in a right direction in FIG. 6. In the embodiment, the channel forming groove 40 is formed linearly along the one direction, i.e., the direction toward the center of the vehicle in the vehicle width direction, and the electrical connection box 100 is fixed to the panel 111. The channel-forming recess 40 is formed over the entire length of the lower cover 105 in the vehicle width direction. That is, the channel-forming recess 40 is formed over the entire length of the lower cover 105 along the surface of the panel 111 gradually inclining toward the vertically lower side in the one direction.In addition, the width of the channel forming recess 40 in the horizontal direction gradually increases as the channel forming recess 40 extends along the surface of the panel 111 toward the vertically lower side. Specifically, in the embodiment, the surface of the panel 111 facing the channel-forming recess 40 in the vertical direction gradually inclines to the vertically lower side the further the surface extends to the center in the vehicle width direction. The width of the channel-forming groove 40 in the horizontal direction gradually increases toward the center in the vehicle width direction. The channel R formed between the channel forming recess 40 and the surface of the panel 111 becomes gradually wider in the horizontal direction as shown in FIGS. 3 and 4, the farther the channel R extends toward the center in the vehicle width direction.The assembly of the electrical connection box 100 having the above-described configuration is performed, for example, by installing the lower cover 105 to the body 103, mounting the various electronic components 102 in the housing space, and installing the upper cover 104 to the body 103. The assembled electrical connection box 100 is installed in the vehicle by being fixed to the panel 111 in the engine room with the fixing brackets 112.In the electrical connection box 100 installed in the engine room, when the vehicle is subjected to high-pressure washing, a liquid may enter the engine room, for example, along the arrow S 1 of FIG. 5. The liquid that has entered the engine compartment may then enter between the electrical connection box 100 and the panel 111. The liquid enters the inlet 30 of the electrical connection box 100. The liquid enters between the bottom cover 105 and the panel 111 through the inlet 30 along the arrow S2 in Fig. 5. The electrical connection box 100 guides the liquid that has entered between the lower cover 105 and the panel 111 to the channel-forming recess 40, through which the liquid flows along the surface of the panel 111 to the vertically lower side as indicated by the arrow S 3 in FIG. 6. The channel-forming recess 40 of the electrical connection box 100 allows the liquid that has entered between the lower cover 105 and the panel 111 to flow to the outside. The liquid discharged to the outside between the undercover 105 and the panel 111 is discharged from the vehicle body through a clearance or the like in the vehicle body.As described above, the electrical connection box 100 includes the channel-forming recess 40 on the bottom 20 vertically below the inlet 30, and the channel-forming recess 40 is bent inside the lower cover 105. On the electrical connection box 100, the channel-forming recess 40 is formed over the entire length of the bottom 20 along the surface of the panel 111 gradually inclining toward the vertically lower side in the one direction. Through the channel-forming recess 40, the electrical connection box 100 allows the liquid that has entered between the floor 20 and the panel 111 to flow outwards along the surface of the panel. Thus, even if the outer surface of the can main body 101 is formed along the surface of the panel 111 and the clearance between the outer surface of the can main body 101 and the surface of the panel 111 is small, the electrical connection can 100 can guide a liquid that has entered through the inlet 30 to the channel-forming recess 40, through which the liquid can be discharged to the outside. Because the electrical connection box 100 guides the liquid that has entered through the inlet 30 to the channel-forming depression 40, the liquid is prevented from accumulating around the inlet 30 and thus around the connection point between the lower cover 105 and the body 103. Consequently, the electrical connection box 100 provides the effect that even if the outer surface of the box main body 101 is formed along the surface of the panel 111 and the clearance between the outer surface of the box main body 101 and the surface of the panel 111 is small, accumulation of the liquid having entered the clearance around the joint between the body 103 and the lower cover 105 and entry into the inside of the box main body 101 including the body 103, the lower cover 105, and other members can be prevented.At the electrical connection box 100, the width of the channel forming recess 40 gradually becomes larger as the channel forming recess 40 extends along the surface of the panel 111 and toward the vertically lower side. Therefore, at the electrical connection box 100, the width of the channel forming recess 40 becomes gradually larger as the channel forming recess 40 extends downstream along the liquid flow. Consequently, the electrical connection box 100 provides the effect that accumulation of the liquid flowing back in the channel-forming recess 40 around a joint between the body 103 and the lower cover 105, and thus entry into the box main body 101 including the body 103, the lower cover 105, and other members, can be prevented.The electrical connection box 100 includes the inlet 30 formed by the vertically lower end portion 106 a, which in turn is a part of the locking mechanism 106. The electrical connection box 100 provides the effect that accumulation of liquid around the vertically lower end portion 106a of the lock mechanism 106, i.e., around the joint between the body 103 and the lower cover 105, and thus entry into the box main body 101 including the body 103, the lower cover 105, and the other members, can be prevented.The above-described wire harness 150 includes the electrical connection box 100, and thus provides the effect that liquid can be prevented from entering the box main body 101 of the electrical connection box 100, the box main body 101 including the body 103, the lower cover 105, and other members.The electrical connection box 100 according to the present invention is not limited to the above-described embodiment, which can be modified in various ways within the scope of the invention defined by the claims. For example, the electrical connection box 100 according to the present invention may include a box main body 101 divided into two layers. According to the present invention, the channel forming recess 40 may also extend along any direction other than the vehicle width direction. According to the present invention, the channel-forming recess 40 need not be formed over the entire length of the lower cover 105 in one direction. That is, according to the present invention, it is sufficient that the channel forming recess 40 is formed along the surface of the panel 111 facing the channel forming recess 40 in the vertical direction, and the surface gradually inclines to the vertically lower side the further the surface extends in one direction, so that a liquid can be discharged to the outside. According to the present invention, the width of the channel forming recess 40 may gradually increase as the channel forming recess 40 extends along the surface of the panel 111 gradually inclining toward the vertically lower side as the surface extends in any direction not limited to the width direction of the vehicle. Alternatively, the width of the channel-forming recess 40 may gradually increase in the vertical direction. Thus, according to the present invention, it is sufficient that the cross section of the channel forming recess 40 becomes gradually larger as the channel forming recess 40 extends to the vertically lower side along the surface of the panel 111 facing the channel forming recess 40 in the vertical direction. In this embodiment, not only the vertically lower end portion 106a but also any other portion of the lock mechanism 106 may serve as the inlet 30. Further, in this embodiment, the inlet 30 may be provided on the bottom 20, and the channel-forming recess 40 may be formed by merely bending the bottom inside the lower cover 105.The electrical connection box according to this embodiment includes the channel-forming recess at least at the bottom of the second housing of the box main body. The channel-forming recess is formed vertically below the inlet by being bent inside the second housing. At the electrical connection box, the channel-forming recess is formed along the surface of the panel to allow a liquid that has entered between the bottom and the panel to flow outward. Thus, even if the outer surface of the can main body is formed along the surface of the panel and the clearance between the outer surface of the can main body and the surface of the panel is small, the electrical connection can guide a liquid having entered the clearance through the inlet to the channel-forming recess through which the liquid can be discharged to the outside. Consequently, the electrical connection box provides the effect that even if the outer surface of the box main body is formed along the surface of the panel and the clearance between the outer surface of the box main body and the surface of the panel is small, accumulation of a liquid having entered the clearance around the joint between the first housing and the second housing and thus entry into the inside of the box main body including a plurality of housings can be prevented.While the invention has been described in terms of specific embodiments for purposes of complete and distinct disclosure, the invention is defined by the appended claims and will enable others skilled in the art to make various modifications and alternatives to the embodiment described herein without departing from the scope of the invention.

Claims

An electrical connection box (100) comprising: a box main body (101) fixed to a vehicle body and comprising a first housing (103) in which an electronic component (102) is mounted, and a second housing (105) installed at a vertically lower side of the first housing (103) with a lock mechanism, wherein the second housing (105) comprises: a frame (10) comprising the lock mechanism (106) at an outer side surface (10a) of the frame (10), a floor (20) disposed parallel to a panel (111) of the vehicle body, the panel (111) facing the floor (20) and covering a vertically lower end part of the frame (10), an inlet (30) provided at an outer surface of the second housing (105) and having a smallest distance from the panel (111), and a channel-forming recess (40) provided vertically below the inlet (30), formed by bending at least a part of the bottom (20) inside the second housing (105), and formed along a surface of the panel (111) gradually inclined toward the vertically lower side the further the surface extends in a direction to allow liquid that has entered between the bottom (20) and the panel (111) to flow outward from between the bottom (20) and the panel (111).The electrical connection box (100) according to claim 1, wherein: the width of the channel-forming recess (40) gradually becomes larger as the channel-forming recess (40) extends along the surface of the panel (111) to the vertically lower side.The electrical connection box (100) of claim 1 or 2, wherein: a portion of the locking mechanism (106) serves as an inlet.A wire harness (150) comprising: the electrical connection box (100) according to any one of claims 1 to 3; and an electric wire (151) electrically connected to the electronic component.

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