JP2004064873A - Drainage structure of electrical junction box - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform the discharge of water within an electric connection box quickly and surely. <P>SOLUTION: This is the drainage structure of an electric connection box which is provided with a drain port 2 at the bottom of the electric connection box, and the drain port 2 has a pair of ramps 16 and a slit-form outlet 17 following the pair of ramps. This structure is provided with space 21 which continues to the slit-form outlet 17 on both sides of the ramp 16. Not a paired ramp 16 but a single one will do. The incline 16a of the ramp 16 may follow the slit-form outlet 17 via a vertical end face 20. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a drainage structure of an electric connection box that efficiently discharges water accumulated in a lower cover of an electric connection box such as a relay box or a fuse box to the outside.
[0002]
[Prior art]
FIG. 5 shows one form of a drainage structure of a lower cover of a conventional electric junction box.
[0003]
A relay box mounted on an automobile is used as the electric connection box. The relay box includes, for example, a lower cover 31 and an upper cover (not shown), a case (not shown) disposed between both covers, and a case. It has electrical components (not shown) such as relays and fuses to be mounted, and a bus bar wiring board (not shown) housed in a case. The wire harness (a plurality of electric wires) led out of the case is bundled in the lower cover 31 and led out from the opening 32 of the lower cover 31.
[0004]
The lower cover 31, the upper cover, and the case, which are the connection box main body, are formed of synthetic resin, and both covers are detachably fixed to the case by locking means such as locking projections (not shown) and the engaging frame 33. . In the present embodiment, two drainage holes 35 for drainage are provided in the bottom wall 34 on the lowest side of the lower cover 31, and rainwater, washing water, dew, etc., which have entered the relay box are discharged from each drainage hole 35 to the outside. To prevent adverse effects such as short circuits on electrical circuits such as relays and wiring boards.
[0005]
The drain holes 35 are formed in a rectangular shape as shown in the side sectional view, the plan view and the 90 ° sectional view in FIGS. 6A to 6C, respectively. It has an outlet (opening) 36 with a cut-out side wall and a hole bottom wall 37 so that water droplets can be led out from the left and right outlets 36 in the horizontal direction.
[0006]
In addition to the above-mentioned embodiment, for example, Japanese Utility Model Laid-Open Publication No. 56-136429 discloses a lower cover (not shown) having a drain hole having one inclined wall, and water droplets are led out along the inclined wall. It has become.
The drain holes 35 can be applied to a fuse box and other electric connection boxes other than the relay box.
[0007]
[Problems to be solved by the invention]
However, in the above-mentioned conventional drainage structure, since water droplets adhere to the drain holes due to surface tension, the water cannot be completely removed and accumulates in the lower cover 31. There is a concern that the insulating property is likely to be reduced due to adhesion. Further, when the outlet 36 of the drain hole 35 is enlarged in order to improve the drainage performance, there is a concern that, for example, water splashed from the outside may enter the lower cover 31 from the drain hole 35 to cause a similar problem. Was.
[0008]
SUMMARY OF THE INVENTION In view of the above, the present invention provides a drain for an electrical junction box that can completely drain water from the bottom of the electrical junction box without being affected by the surface tension of water, even if the outlet of the drain hole is made smaller. The purpose is to provide a structure.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the drainage structure for an electrical junction box according to claim 1 of the present invention is a drainage structure for an electrical junction box provided with a drainage hole at the bottom of the electrical junction box, wherein the drainage hole includes: It is characterized in that it has a pair of opposed inclined portions and a slit-shaped outlet following the pair of inclined portions.
With the above configuration, the water in the electric connection box is guided along the pair of inclined portions and flows down vigorously, and the water flowing down along each inclined portion interferes with each other and increases the discharge force in the pushing direction, The water in the electrical junction box is drained quickly and without residue. Further, since the slit-shaped outlet is narrow, it is possible to prevent water and dust from entering the inside of the electric connection box from the outside through the outlet.
[0010]
The drainage structure for an electric junction box according to claim 2 is characterized in that, in the drainage structure for an electric junction box according to claim 1, a space that continues to the slit-shaped outlet is provided on both sides of the inclined portion. .
With the above configuration, the amount of water that exceeds the discharge capacity of the slit-shaped outlet is temporarily stored in the spaces on both sides, and the water in the spaces on both sides is integrated with the strong momentum water flowing through the inclined portion and flows out of the slit-shaped outlet. Emitted reliably. The water that falls into the space on both sides from the inclined portion also increases the drainage power of the water in the space. Further, since the inclined portion protrudes between the spaces on both sides, the surface tension of the water in the drain hole is weakened, and the water is discharged smoothly and quickly.
[0011]
The drainage structure for an electric connection box according to claim 3, wherein the drainage hole is provided in a bottom portion of the electric connection box, wherein the drainage hole has a slope and a space on both sides of the slope. And a slit-shaped outlet following the inclined portion and the space.
With the above configuration, the water is guided along the inclined portion and flows down vigorously, and the amount of water exceeding the discharge capacity of the slit-shaped outlet is temporarily stored in the spaces on both sides, and the water in the spaces on both sides is inclined. It is integrated with the strong momentum of water flowing through and is reliably discharged from the slit-shaped outlet. The water that falls into the space on both sides from the inclined portion also increases the drainage power of the water in the space. Further, since the inclined portion protrudes between the spaces on both sides, the surface tension of the water in the drain hole is weakened, and the water is discharged smoothly and quickly. The slit-shaped narrow outlet prevents entry of water and dust from the outside.
[0012]
The drainage structure for an electric connection box according to claim 4 is the drainage structure for an electric connection box according to claim 3, wherein the pair of inclined portions are provided to face each other, and the slit-shaped outlet is provided between the pair of inclined portions. It is characterized by being provided.
According to the above configuration, the water in the electric connection box is guided along the pair of inclined portions and flows down vigorously, and the waters flowing down along the respective inclined portions interfere with each other to increase the discharging force. The water inside is discharged quickly and without residue.
[0013]
The drainage structure for an electric junction box according to claim 5 is the drainage structure for an electric junction box according to any one of claims 1 to 4, wherein the inclined surface of the inclined portion has a slit-like shape through a vertical end surface. It is characterized by following the exit.
According to the above configuration, the water guided vigorously along the inclined surface is further accelerated on the vertical end surface and discharged vigorously from the slit-shaped outlet. Further, the space where the water flowing down along the pair of inclined portions interferes with each other is increased, so that the discharging power of the water is further increased, and the drainage capacity is improved.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 and 2 show an embodiment of a synthetic resin lower cover including a drainage structure of an electric junction box according to the present invention.
The lower cover 1 has almost the same appearance as that of the conventional example shown in FIG. 5, but the shape of the drain hole 2 is greatly different from that of the conventional example as shown in FIGS.
[0015]
1 and 2, the lower cover 1 is formed in a rectangular shape, and an inclined bottom wall 7 is provided following two orthogonal side walls 3 and 4, and the inclined bottom wall 7 is connected to the other two side walls 5 and 5. It continues to the lower horizontal bottom wall 8 which is 6 steps lower. Two drain holes 2 are provided near both left and right sides of the low bottom wall (bottom portion) 8.
[0016]
An opening 22 for leading out a wire harness is provided in the side wall 5 following the bottom wall 8. At the upper part of each of the side walls 3 to 6, a flexible locking frame piece 9 for an intermediate case (not shown) is protruded, and at the bottom side, a bracket 10 for fixing to the vehicle body is provided.
[0017]
Each drainage hole 2 is formed inside a small substantially rectangular box-shaped wall portion 11 (FIG. 2) projecting downward from the bottom wall 8. The bottom wall 13 has a partially open bottom wall 13 and a protruding wall 14 extending downward from one side wall 12. The protruding wall 14 functions as a guide wall for facilitating the drop of water derived from the outlet (opening) of the bottom wall 13 to the outside.
[0018]
3A is a side sectional view of the drain hole 2, FIG. 3B is a plan view of the same, FIG. 3C is a sectional view in a direction orthogonal to FIG. 3A, and FIG. 2) is a perspective view of relevant parts showing a substantially half on one side.
[0019]
The drain hole 2 includes an inclined wall (inclined portion) 16 having a pair of tapered inclined surfaces 16 a in a concave portion 15 inside the substantially rectangular box-shaped wall portion 11. Has a slit-shaped narrow outlet (opening) 17 in the bottom wall 13. The inclined wall 16 is located opposite the left and right sides at the center in the width direction of the concave portion 15.
[0020]
As shown in FIG. 4, one end (long side) 16b of the inclined wall 16 is orthogonal to the vertical inner wall 18 of the concave portion 15, and the other end (short side) 16c of the inclined wall 16 is a vertical inner surface 19 of the slit-shaped outlet 17. And are located on the same plane. One end 16b of the inclined surface 16a intersects with the bottom wall (bottom portion) 8 of the lower cover 1 (FIG. 1), and the other end 16c of the inclined surface 16a has an end surface which is flush with the vertical inner surface 19 of the slit-shaped outlet 17. (Vertical plane) 20. The angle of inclination of the inclined surface 16b is preferably about 60 ° in order to enhance the dropping property of water droplets.
[0021]
On both sides of the inclined wall 16, a substantially rectangular space 21 substantially defined by the inclined wall 16 is formed, and each space 21 communicates with the slit-shaped outlet 17. The lower end 16c of the inclined surface 16a of the inclined wall 16 is located at a position which is about half the depth of the recess 15 as shown in FIG. In order to make the lower end 16c of the inclined surface 16a coincide with the upper end or the lower end of the slit-shaped outlet 17, the angle of the inclined surface 16a can be set deep (steep) in FIG. 4, but FIG. The presence of the vertical surface 20 following the slit-shaped outlet 17 as described above accelerates the falling speed of water droplets from the inclined surface 16a, and increases drainage.
[0022]
The water droplets on the bottom wall 8 of the lower cover 1 flow down while accelerating along the inclined surface 16a. However, since there is a substantially rectangular space 21 on both sides of the inclined wall 16, for example, the amount of water is large and cannot be discharged at once. In this case, the liquid is temporarily stored in the space 21 and then sequentially discharged from the slit-shaped outlet 17. The water in the space 21 is reliably discharged together with the force of the water falling along the inclined surface 16a.
[0023]
In addition, the adoption of the slit-shaped narrow outlet 17 prevents splashing of water from the outside, washing water, and the like from entering the lower cover 1 from the outlet 7, thereby increasing the waterproofness of the electrical junction box.
[0024]
In the case where the amount of water that intrudes is small or when the drain holes 2 are provided near the side walls 5 and 6 of the lower cover 1, the state shown in FIG. It is also possible to provide spaces 21 on both sides of 16. Further, it is also possible to eliminate the space 21 and to form the recess 15 only with the pair of left and right inclined walls 16. In addition, the drain hole 2 is not limited to the lower cover 1, but is effective when it is provided at the bottom of the connection box body made of synthetic resin. The lower cover 1 is also a part of the connection box main body.
[0025]
【The invention's effect】
As described above, according to the first aspect of the present invention, the water at the bottom of the electric connection box is efficiently discharged while being smoothly guided by the pair of inclined portions. This prevents the wire harness from being held in the attached state, thereby preventing problems such as a decrease in insulation performance of the wire harness. In addition, since the slit-shaped narrow outlet prevents intrusion of splashing water, washing water, dust and the like from the outside, the insulation performance of the wire harness in the electric connection box is also prevented from being lowered.
[0026]
According to the second aspect of the present invention, since the temporary water storage portion is formed by the spaces on both sides of the inclined portion, the drainage can be sufficiently performed even at the narrow slit-shaped outlet, and the water drops from the inclined portion into the spaces on both sides. The draining water enhances the drainage power of the water in the space, and the inclined portion protrudes between the spaces on both sides, so that the surface tension of the water in the drain hole is weakened. The water discharge performance can be improved while reliably preventing the occurrence of water, and the effect of the invention described in claim 1 is further promoted.
[0027]
According to the third aspect of the present invention, the water at the bottom of the electric connection box is efficiently discharged while being smoothly guided by the inclined portion, and the splashing water, washing water, and dust from the outside are provided by the narrow slit-shaped outlet. The space on both sides of the inclined part constitutes a temporary reservoir for water, and even a narrow slit-shaped outlet allows sufficient drainage, and the water falling from the inclined part into the space on both sides The ability to drain water from the space is enhanced, and the inclined portion protrudes between the spaces on both sides, which reduces the surface tension of the water in the drain hole, thereby reliably preventing water from entering from outside. While improving the water discharge performance. As a result, for example, the state in which water is attached to the wire harness in the electric connection box is not maintained, and problems such as a decrease in insulation performance of the wire harness are prevented.
[0028]
According to the fourth aspect of the present invention, the water that has flowed down along the pair of inclined portions interferes with each other to increase the discharging power, thereby improving the drainage performance of the water in the electric connection box. The effects of the described invention are further promoted.
[0029]
According to the fifth aspect of the present invention, the water guided vigorously along the inclined surface is further accelerated by the vertical end face, so that the drainage capacity is improved, and the effects of the first to fourth aspects of the present invention are further enhanced. Will be encouraged.
[Brief description of the drawings]
FIG. 1 is a plan view showing an embodiment of a lower cover having a drainage structure for an electric junction box according to the present invention.
FIG. 2 is a side view showing the lower cover.
3 (a) is a side sectional view, FIG. 3 (b) is a plan view, and FIG. 3 (c) is a sectional view in a direction orthogonal to FIG. 3 (a).
FIG. 4 is a perspective view of a main part showing a drain hole in the same manner.
FIG. 5 is a plan view showing a lower cover having a conventional drainage structure.
6 (a) is a side sectional view, FIG. 6 (b) is a plan view, and FIG. 6 (c) is a sectional view in a direction orthogonal to FIG. 6 (a).
[Explanation of symbols]
2 Drainage hole 16 Inclined wall (inclined part)
16a inclined surface 17 slit-shaped outlet 20 end surface 21 space

Claims (5)

In the drainage structure of an electric junction box provided with a drain hole at a bottom portion of the electric junction box, the drain hole has a pair of opposed inclined portions and a slit-shaped outlet following the pair of inclined portions. Characteristic drainage structure of electrical junction box. The drainage structure for an electric junction box according to claim 1, wherein a space leading to the slit-shaped outlet is provided on both sides of the inclined portion. In the drainage structure for an electric connection box provided with a drainage hole at a bottom portion of the electric connection box, the drainage hole includes a slope, a space on both sides of the slope, and a slit-like shape connected to the slope and the space. And an outlet for the electric junction box. The drainage structure for an electric junction box according to claim 3, wherein the inclined portions are provided so as to face each other, and the slit-shaped outlet is provided between the pair of inclined portions. The drainage structure for an electric junction box according to any one of claims 1 to 4, wherein the inclined surface of the inclined portion continues to the slit-shaped outlet through a vertical end surface.

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