JP2022037543A - Electric connection box - Google Patents

Abstract

To provide an electric connection box provided with high waterproof performance.SOLUTION: An electric connection box 1 comprises: a resin lower case 2 which houses a circuit board 4; a metal upper cover 3 which is engaged within the lower case 2 to block an upper opening 2o of the lower case 2. A front opening 21o is provided in the lower case 2. A rear wall part 22 facing the front opening 21o and a pair of side wall parts (a left wall part 23, a right wall part 24) each connected to a different edge of the rear wall part 22 and facing each other form an inner wall 25. An outer wall 26 is formed with a predetermined spacing with respect to a part of the inner wall 25 including a corner 2d between the rear wall part 22 and the right wall part 24. A double-wall structure 27 is formed in which an upper edge 25e of the inner wall 25 comes into contact with a lower edge of the upper cover 3 (more specifically, a lower edge 30f of a body part 30) and an upper edge 26e of the outer wall 26 is located above the inner wall 25. A water discharge passage 28 is provided between the inner wall 25 and the outer wall 26 by connecting a lower edge portion of the inner wall 25 and a lower edge portion of the outer wall 26.SELECTED DRAWING: Figure 2

Description

The present invention relates to an electrical junction box.

Conventionally, an electric junction box that is connected to an electric device mounted on a vehicle via a wire harness has been known. The electrical junction box is arranged, for example, inside the engine room or the instrument panel.

By the way, some such electrical connection boxes have a double-walled structure in order to prevent water from entering from the fitting portion of the housing (see Patent Document 1). However, even if a double wall structure is provided in some places for a continuous long fitting portion, the effect obtained if there is a section where the fitting portion is exposed will be limited, and the effect of the double wall structure will be limited. If water splashes vigorously on the drainage port, the water may flow back from the drainage port and flood the fitting portion.

In particular, when cleaning is performed using a high-pressure washer, water is vigorously concentrated on one point, so it is easy for water to directly hit the mating part through the gap between the outer walls of the double-walled structure, and water. Was infiltrated into the interior. In addition, since at least one drainage port must be provided for each double-walled structure, water tends to be directly applied to one of the drainage ports, and there is a risk that water may infiltrate inside due to flooding of the fitting portion. rice field. Therefore, there has been a demand for an electric connection box having high waterproof performance that prevents water from entering the inside.

Japanese Unexamined Patent Publication No. 2020-80589

It is an object of the present invention to provide an electrical connection box that has acquired high waterproof performance.

The present invention comprises a resin lower case that houses a circuit board and a metal upper cover that is fitted into the lower case and closes the upper opening of the lower case. The lower case is provided with a front opening. An inner wall is composed of a rear wall portion facing the front opening and a pair of side wall portions facing each other connected to each end side of the rear wall portion, and a corner portion between the rear wall portion and at least one of the side wall portions. The outer wall is configured with a predetermined interval from a part of the inner wall including the inner wall, the upper end edge of the inner wall abuts on the lower end surface of the upper cover, and the upper end edge of the outer wall is from the inner wall. It also has a double wall structure located on the upper side, and is characterized by being an electrical connection box in which a drainage passage is provided between the inner wall and the outer wall by connecting the inner wall and the lower end portion of the outer wall.

According to the present invention, high waterproof performance can be obtained.
More specifically, in the electrical connection box according to the present invention, the upper end edge of the outer wall is located above the inner wall while ensuring a predetermined waterproof performance by abutting the upper end edge of the inner wall on the lower end surface of the upper cover. By doing so, the fitting portion between the lower case and the upper cover is covered so that water does not directly hit the fitting portion. Further, in the electrical connection box according to the present invention, since the continuous long fitting portion is covered with the outer wall of the double wall structure without a gap so as to wrap around the corner portion, the gap between the outer wall and the outer wall of the double wall structure is passed. It also prevents water from directly hitting the mating part. In addition, the electrical connection box according to the present invention is provided with a drainage passage between the inner wall and the outer wall. Therefore, the water that has crossed the outer wall can be smoothly discharged, and the fitting portion is not flooded. Therefore, high waterproof performance can be obtained.

As an aspect of the present invention, the upper end edge of the outer wall may abut on the lower end surface of the upper cover.
According to the present invention, it is possible to prevent the water that hits the side surface of the upper cover and the like from entering the drainage passage and the water that has traveled through the upper cover from entering the drainage passage. Therefore, the amount of water entering the drainage passage can be reduced, and the fitting portion is not flooded. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, one end side of the drainage passage may be opened and the other end side may be closed.
According to the present invention, since the number of drainage ports is one in a long drainage passage that is continuous so as to go around the corners, it is difficult for water to directly hit the drainage ports. In this regard, if a drainage port is provided on one end side shielded by the surrounding structure, the possibility that water directly hits the drainage port can be further reduced. Therefore, water does not flow back from the drain port, and the fitting portion is not flooded. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, the opening end of the drainage passage may be provided in the middle portion of the side wall portion separated from the corner portion between the front opening and the side wall portion.
According to the present invention, the drainage port is provided at a position around the corner from the front opening, so that the drained water does not splash on the front opening. In addition, the drained water does not splash on the connector socket inserted in the front opening. Therefore, it is possible to prevent water from entering through the front opening through the connector socket or the like. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, the rear wall portion or the side wall where the closed end of the drainage passage is separated from the corner portion between the rear wall portion and the side wall portion and the corner portion between the front opening and the side wall portion. It may be provided in the middle part of the part.
According to the present invention, the closed wall that closes the drainage passage is connected to the middle portion of the rear wall portion or the side wall portion that constitutes the inner wall, so that the rigidity of the inner wall is improved. Therefore, the contact pressure between the upper end edge of the inner wall and the lower end surface of the upper cover can be secured, and the waterproof performance can be improved. Further, even if the water flowing back through the drainage passage loses a place to escape and pushes the inner wall, it is possible to prevent the inner wall from being distorted. As a result, it is possible to prevent the inner wall from being distorted and a slight gap between the upper end edge of the inner wall and the lower end surface of the upper cover. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, an intermediate wall extending downward from the lower end surface of the upper cover may be provided, and the intermediate wall may be arranged between the inner wall and the outer wall.
According to the present invention, the intermediate wall extending downward is meshed between the inner wall extending upward and the outer wall. Therefore, the infiltration route when water invades becomes long, and the waterproof performance can be improved. Further, since the outer wall is supported from the inside by the intermediate wall, it is possible to prevent the outer wall from being distorted even if water vigorously hits the outer wall and pushes the outer wall. As a result, when the outer wall is distorted, it is possible to prevent the width of the drainage passage from becoming smaller and hindering smooth drainage. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, there is a first inner wall guide portion extending downward from the lower end surface of the upper cover integrally with the intermediate wall, and the guide surface in the first inner wall guide portion is the tip end. It is inclined inward from the side toward the base end side, and the inner wall may be pressed and supported inward in a state of being in contact with the outer peripheral surface of the inner wall.

INDUSTRIAL APPLICABILITY According to the present invention, in the process of assembling the electrical junction box, when the lower case and the upper cover are fitted, the upper end edge of the inner wall can be guided to the correct position along the first inner wall guide portion. Therefore, the inner wall and the intermediate wall are correctly assembled by one fitting operation. As a result, the assemblability of the electrical junction box can be improved. Further, in the state where the lower case and the upper cover are fitted, the first inner wall guide portion presses the inner wall to regulate the displacement, so that the rigidity of the inner wall is improved. Therefore, it is possible to prevent the inner wall from being distorted and a slight gap between the upper end edge of the inner wall and the lower end surface of the upper cover. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, there is a second inner wall guide portion extending downward from the lower end surface of the upper cover inside the intermediate wall, and the guide surface in the second inner wall guide portion is the tip end. It is inclined outward from the side toward the proximal end side, and the inner wall may be pressed and supported outward in a state of being in contact with the inner peripheral surface of the inner wall.

INDUSTRIAL APPLICABILITY According to the present invention, in the process of assembling the electrical junction box, when the lower case and the upper cover are fitted, the upper end edge of the inner wall can be guided to the correct position along the second inner wall guide portion. Therefore, the inner wall and the intermediate wall are correctly assembled by one fitting operation. As a result, the assemblability of the electrical junction box can be improved. Further, in the state where the lower case and the upper cover are fitted, the second inner wall guide portion presses the inner wall to regulate the displacement, so that the rigidity of the inner wall is improved. Therefore, it is possible to prevent the inner wall from being distorted and a slight gap between the upper end edge of the inner wall and the lower end surface of the upper cover. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, the first outer wall guide portion extending downward from the lower end surface of the upper cover is provided outside the intermediate wall, and the guide surface in the first outer wall guide portion is the tip end. It is inclined inward from the side toward the base end side, and the outer wall may be pressed and supported inward in a state of being in contact with the outer peripheral surface of the outer wall.

INDUSTRIAL APPLICABILITY According to the present invention, when the lower case and the upper cover are fitted in the assembly process of the electrical junction box, the upper end edge of the outer wall can be guided to the correct position along the first outer wall guide portion. Therefore, the outer wall and the intermediate wall are correctly assembled by one fitting operation. As a result, the assemblability of the electrical junction box can be improved. Further, in the state where the lower case and the upper cover are fitted, the first outer wall guide portion presses the outer wall to regulate the displacement, so that the rigidity of the outer wall is improved. Therefore, when the outer wall is distorted, it is possible to prevent the width of the drainage passage from becoming small and hindering smooth drainage. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, there is a second outer wall guide portion extending downward from the lower end surface of the upper cover integrally with the intermediate wall, and the guide surface in the second outer wall guide portion is the tip end. It is inclined outward from the side toward the base end side, and the outer wall may be pressed and supported outward in a state of being in contact with the inner peripheral surface of the outer wall.

INDUSTRIAL APPLICABILITY According to the present invention, when the lower case and the upper cover are fitted in the assembly process of the electrical junction box, the upper end edge of the outer wall can be guided to the correct position along the second outer wall guide portion. Therefore, the outer wall and the intermediate wall are correctly assembled by one fitting operation. As a result, the assemblability of the electrical junction box can be improved. Further, in the state where the lower case and the upper cover are fitted, the second outer wall guide portion presses the outer wall to regulate the displacement, so that the rigidity of the outer wall is improved. Therefore, when the outer wall is distorted, it is possible to prevent the width of the drainage passage from becoming small and hindering smooth drainage. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, a curved portion curved with respect to a virtual line passing through the center of the inner wall and the outer wall may be provided in the middle portion of the intermediate wall.
According to the present invention, when a curved portion that is raised outward is provided, the outer wall is gently deformed along the curved surface, so that it is possible to prevent stress from concentrating on a specific region of the outer wall while pressing the outer wall. can. On the contrary, when the curved portion raised inward is provided, the inner wall is gently deformed along the curved surface, so that it is possible to prevent the stress from concentrating on a specific region of the inner wall while pressing the inner wall. .. Further, since the width of the drainage passage is regulated by the curved portion, it is possible to prevent the passage width of the drainage passage from becoming smaller when the inner wall or the outer wall is distorted, which hinders smooth drainage. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, a second inner wall guide portion that presses and supports the inner wall to the outside in a state of being in contact with the inner peripheral surface of the inner wall, and an outer wall of the outer wall in a state of being in contact with the inner peripheral surface of the outer wall. It has a second outer wall guide portion that presses and supports the second inner wall guide portion, and the second inner wall guide portion and the second outer wall guide portion may be displaced with respect to each other in a direction along the intermediate wall.

According to the present invention, when the second outer wall guide portion is displaced toward the rear wall portion with respect to the second inner wall guide portion, the second outer wall guide portion is separated from the drain port in the drainage passage. Therefore, it is possible to prevent the smooth drainage of the water flowing while accelerating toward the drainage port from being hindered. On the contrary, when the second outer wall guide portion is displaced toward the front opening side with respect to the second inner wall guide portion, the second outer wall guide portion is close to the drainage port in the drainage passage. Therefore, it is possible to prevent water from flowing back from the drain port. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, a locking portion may be provided so as to be able to lock the inner wall and the upper cover.
According to the present invention, the lower case and the upper cover can be fixed in a fitted state. Further, by locking the inner wall and the upper cover by the locking portion, it is possible to prevent the locking portion from coming off even if the outer wall is distorted due to the vigorous application of water to the outer wall. Further, when the locking portion locks the inner wall and the upper cover, it is possible to prevent the inner wall from being distorted and a slight gap between the upper end edge of the inner wall and the lower end surface of the upper cover. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, the locking portion is composed of a locking hole and a locking claw that hangs on the locking hole, and the locking hole or the locking claw on the inner wall is provided. The region including the portion may be formed thinner than the other regions.

According to the present invention, in the process of assembling the electrical connection box, when the lower case and the upper cover are fitted, the portion of the inner wall provided with the locking hole or the locking claw is easily deformed. Therefore, it easily engages with the locking claws or locking holes on the upper cover side, which are made of metal. As a result, the assemblability of the electrical junction box can be improved. Further, in the other regions of the inner wall, the inner wall is thickly formed to ensure rigidity. Therefore, it is possible to prevent the inner wall from being distorted and a slight gap between the upper end edge of the inner wall and the lower end surface of the upper cover. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, crushing ribs may be provided on at least one of the upper end edge of the inner wall and the upper end edge of the outer wall.
According to the present invention, the lower case and the upper cover can be fixed without rattling. In particular, when the crushing rib is provided on the upper end edge of the inner wall, the contact pressure with the lower end surface of the upper cover can be increased around the crushing rib on the upper end edge of the inner wall, and the waterproof performance can be improved. .. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, a drip-proof sheet covering the upper surface of the upper cover may be provided, and the drip-proof sheet may project outward from the outer peripheral end portion of the upper cover.
According to the present invention, it is possible to prevent the water that hits the side surface of the upper cover and the like from entering the drainage passage and the water that has traveled through the upper cover from entering the drainage passage. Therefore, the amount of water entering the drainage passage can be reduced, and the fitting portion is not flooded. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, the connector socket may be inserted through the front opening, and the drip-proof sheet may project to the upper side of the connector socket.
INDUSTRIAL APPLICABILITY According to the present invention, it is possible to prevent water that hits the side surface of the upper cover and the like from splashing on the connector socket and water that has traveled through the upper cover from splashing on the connector socket. Therefore, it is possible to prevent water from entering through the front opening through the connector socket or the like. Therefore, high waterproof performance can be obtained.

Further, as an aspect of the present invention, the drip-proof sheet may be bent, and at least one of the side wall portion and the rear wall portion may be covered with the bent piece in the drip-proof sheet.
INDUSTRIAL APPLICABILITY According to the present invention, it is possible to reliably prevent water from directly splashing on the fitting portion of the lower case and the upper cover in each wall portion covered with the bent piece of the drip-proof sheet. In addition, in each wall covered with the bent pieces of the drip-proof sheet, the water that hits the side surface of the upper cover and bounces off enters the drainage passage, and the water that has traveled through the upper cover enters the drainage passage. It can be surely prevented. Therefore, the amount of water entering the drainage passage can be reliably reduced, and the fitting portion is not flooded. Therefore, high waterproof performance can be obtained.

Perspective view of the electrical junction box. An exploded perspective view of the electrical junction box. Perspective view of the lower case. Top view of the lower case. A cross-sectional view taken along the line AA and a cross-sectional view taken along the line BB in FIG. Perspective view of the upper cover. Bottom view of the upper cover. FIG. 7 is a cross-sectional view taken along the line CC and a cross-sectional view taken along the line DD. FIG. 1 is a cross-sectional view taken along the line EE of FIG. FIG. 1 is a cross-sectional view taken along the line FF of FIG. Explanatory drawing explaining the function of the 1st inner wall guide part and the 2nd inner wall guide part. Explanatory drawing explaining the function of the 1st outer wall guide part and the 2nd outer wall guide part. Top view of the lower case according to another embodiment. Top view of the lower case according to another embodiment.

An embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view of the electrical connection box 1, and FIG. 2 is an exploded perspective view of the electrical connection box 1. 3 is a perspective view of the lower case 2, FIG. 4 is a top view of the lower case 2, and FIG. 5 is a cross-sectional view taken along the line AA and a cross-sectional view taken along the line BB of FIG. 6 is a perspective view of the upper cover 3, FIG. 7 is a bottom view of the upper cover 3, and FIG. 8 is a cross-sectional view taken along the line CC and a cross-sectional view taken along the line DD of FIG.

9 is a cross-sectional view taken along the line EE of FIG. 1, and FIG. 10 is a cross-sectional view taken along the line EF of FIG. FIG. 11 is an explanatory diagram for explaining the functions of the first inner wall guide unit 33 and the second inner wall guide unit 34, and FIG. 12 is an explanatory diagram for explaining the functions of the first outer wall guide unit 35 and the second outer wall guide unit 36. be. In the present application, as shown in the figure, the front-back direction, the up-down direction, and the left-right direction are defined.

As shown in FIGS. 1 and 2, the electrical junction box 1 includes a lower case 2, an upper cover 3, and a circuit board 4. The circuit board 4 includes a connector socket 5, and a wire harness 7 is connected to the connector socket 5 via the connector 6. Further, the electrical connection box 1 is covered with a drip-proof sheet 8.

As shown in FIGS. 3 to 5, the lower case 2 is a resin (polypropylene resin) housing for accommodating the circuit board 4. In addition to the bottom wall portion 20, the lower case 2 has wall portions 21 to 24 extending upward from the outer peripheral end portion of the bottom wall portion 20. The inner wall 25 is formed by the wall portions 21 to 24. Further, it constitutes an outer wall 26 that covers a part of the inner wall 25. At the upper end of the lower case 2, there is no wall and an upper opening 2o is formed.

The bottom wall portion 20 is formed in a rectangular shape when viewed from above. A plurality of reinforcing ribs (not shown) are provided on the upper surface of the bottom wall portion 20. Further, the front wall portion 21 extends upward from the front end portion of the bottom wall portion 20. The front wall portion 21 is a vertical wall perpendicular to the front-rear direction, and most of the front wall portion 21 is provided with a rectangular front opening 21o. Further, the rear wall portion 22 extends upward from the rear end portion of the bottom wall portion 20. The rear wall portion 22 is a vertical wall perpendicular to the front-rear direction and faces the front wall portion 21.

The left wall portion 23 extends upward from the left end portion of the bottom wall portion 20. The left wall portion 23 is a vertical wall perpendicular to the left-right direction, is connected to the left side of the front wall portion 21 via the corner portion 2a, and is connected to the left side of the rear wall portion 22 via the corner portion 2b. ing. Further, the right wall portion 24 extends upward from the right end portion of the bottom wall portion 20. The right wall portion 24 is a vertical wall perpendicular to the left-right direction, is connected to the right side of the front wall portion 21 via the corner portion 2c, and is connected to the right side of the rear wall portion 22 via the corner portion 2d. ing.

In the lower case 2, each wall portion 21 to 24 is arranged along the outer peripheral end portion of the bottom wall portion 20, and an inner wall 25 that surrounds the space in a rectangular shape when viewed from above is configured. As shown in FIGS. 9 and 10, the upper end edge 25e of the inner wall 25 abuts on the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body 30). When the lower case 2 and the upper cover 3 are fitted together, the contact pressure between the upper end edge 25e of the inner wall 25 and the lower end surface 30f of the main body 30 is designed to be an optimum value. The upper end edge 25e of the inner wall 25 is provided with a crushing rib 251 that is crushed by the contact pressure.

Further, the lower case 2 is configured with an outer wall 26 so as to cover the rear wall portion 22, the right wall portion 24, and the corner portion 2d connecting the both wall portions 22 and 24. The outer wall 26 is arranged at a predetermined distance from the corner portion 2d connecting the rear wall portion 22, the right wall portion 24, and the both wall portions 22, 24. Therefore, the outer wall 26 has an L-shape when viewed from above. As shown in FIGS. 9 and 10, the upper end edge 26e of the outer wall 26 is located above the inner wall 25. Further, the upper end edge 26e of the outer wall 26 also partially abuts on the lower end surface of the upper cover 3 (specifically, the lower end surface 31f of the extending portion 31). Therefore, the crushing rib 261 is also provided on the upper end edge 26e of the outer wall 26.

As described above, in the lower case 2, the inner wall 25 and the outer wall 26 form the double wall structure 27. The left wall portion 23 of the inner wall 25 is provided with two locking claws 252 constituting the locking portion 11 on the outer peripheral surface thereof. Further, the right wall portion 24 of the inner wall 25 is also provided with two locking claws 252 constituting the locking portion 11 on the outer peripheral surface thereof. The region of the inner wall 25 including the portion provided with the locking claw 252 is formed thinner than the other regions (see region R in FIG. 4). At this point, the corners 2b and 2d are also thinly formed. By doing so, the effect described later can be further brought out.

In addition, in the lower case 2, the lower end portion of the inner wall 25 and the outer wall 26 is connected by an extended portion of the bottom wall portion 20, and a drainage passage 28 is formed between the inner wall 25 and the outer wall 26. One end side of the drainage passage 28 is opened, and the other end side is closed. The opening of the drainage passage 28 functions as a drainage port 28o. Therefore, the number of drainage ports 28o is one in the long drainage passage 28 that is continuous so as to go around the corner portion 2d. In the lower case 2, a drainage port 28o is provided on the corner portion 2c side shielded by a peripheral structure (not shown). By doing so, the effect described later can be further brought out.

In addition, in the lower case 2, the opening end (drainage port 28o) of the drainage passage 28 is provided in the middle portion of the right wall portion 24 in the front-rear direction. Specifically, it is provided on the corner portion 2c side of the right wall portion 24 with respect to the center in the front-rear direction while being separated from the corner portion 2c. Furthermore, in the lower case 2, the closed end of the drainage passage 28 is provided in the middle portion of the rear wall portion 22 in the left-right direction. Specifically, it is provided on the corner portion 2b side of the rear wall portion 22 with respect to the center in the left-right direction while being separated from the corner portion 2b. The closed end of the drainage passage 28 is closed by a closed wall 29 extending from the outer peripheral surface of the rear wall portion 22 toward the rear side. The closed wall 29 also functions as a reinforcing rib for the rear wall portion 22.

As shown in FIGS. 6 to 8, the upper cover 3 is a metal (aluminum alloy) lid that is fitted to the lower case 2 and closes the upper opening 2o of the lower case 2. The upper cover 3 includes a main body portion 30, an extension portion 31, an intermediate wall 32, a first inner wall guide portion 33, a second inner wall guide portion 34, a first outer wall guide portion 35, and a second outer wall guide portion. It has 36 and. Since the upper cover 3 serves as a bracket for the electrical connection box 1, a plurality of bolt holes 3h are formed.

The main body 30 is formed in a rectangular shape when viewed from below. On the lower end surface 30f of the main body portion 30, four board fixing seats 301 for fixing the circuit board 4 are provided. Further, the extending portion 31 is a strip-shaped protruding portion extending in the front-rear direction extending from the right end portion of the main body portion 30 toward the right side and the front side. A bolt stay 311 extending downward is provided on the lower end surface 31f of the extending portion 31. The bolt stay 311 is also formed with a long hole-shaped bolt hole 3h that penetrates in the left-right direction.

The intermediate wall 32 extends downward from the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body 30). The intermediate wall 32 is arranged along the outer peripheral end of the main body 30, and is formed in a rectangular shape when viewed from below. When the lower case 2 and the upper cover 3 are fitted, the intermediate wall 32 is arranged between the inner wall 25 and the outer wall 26. The straight portion on the right end side of the double wall structure 27 is provided with a curved portion 321 that is curved with respect to the virtual line L passing through the center of the inner wall 25 and the outer wall 26. The curved portion 321 refers to an exceptionally outwardly raised portion of the intermediate wall 32 extending in the front-rear direction. However, the curved portion 321 that is raised inward may be provided.

The first inner wall guide portion 33 is integrally extended with the intermediate wall 32 from the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body portion 30) toward the lower side. The first inner wall guide portion 33 extends downward from the intermediate wall 32, and the guide surface 33f abutting on the outer peripheral surface of the inner wall 25 is inclined inward as it goes from the tip end side to the base end side. Further, when the lower case 2 and the upper cover 3 are fitted, the first inner wall guide portion 33 comes into contact with the outer peripheral surface of the inner wall 25 and presses and supports the inner wall 25 inward. In the upper cover 3, the two first inner wall guide portions 33 are arranged on the left end side of the main body portion 30, and the two first inner wall guide portions 33 are arranged on the right end side of the main body portion 30. Has been done. Further, each first inner wall guide portion 33 is provided with a locking hole 332 that constitutes the locking portion 11.

The second inner wall guide portion 34 extends downward from the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body portion 30) inside the intermediate wall 32. The second inner wall guide portion 34 extends downward from the intermediate wall 32, and the guide surface 34f abutting on the inner peripheral surface of the inner wall 25 is inclined outward as it goes from the tip end side to the base end side. Further, when the lower case 2 and the upper cover 3 are fitted, the second inner wall guide portion 34 comes into contact with the inner peripheral surface of the inner wall 25 and presses and supports the inner wall 25 to the outside. In the upper cover 3, one second inner wall guide portion 34 is arranged between two first inner wall guide portions 33 on the left end side of the main body portion 30, and one second inner wall guide portion 34 is further arranged. Is arranged between the two first inner wall guide portions 33 on the right end side of the main body portion 30.

The first outer wall guide portion 35 extends downward from the lower end surface of the upper cover 3 (specifically, the lower end surface 31f of the extension portion 31) to the outside of the intermediate wall 32. The first outer wall guide portion 35 extends downward from the intermediate wall 32, and the guide surface 35f abutting on the outer peripheral surface of the outer wall 26 is inclined inward as it goes from the tip end side to the base end side. Further, when the lower case 2 and the upper cover 3 are fitted, the first outer wall guide portion 35 comes into contact with the outer peripheral surface of the outer wall 26 and presses and supports the outer wall 26 inward. In the upper cover 3, the two first outer wall guide portions 35 are arranged in the extension portion 31 extending from the main body portion 30. The first outer wall guide portion 35 on the rear side is integrally configured with the bolt stay 311 described above, and also serves as a reinforcing rib of the bolt stay 311.

The second outer wall guide portion 36 is integrally extended with the intermediate wall 32 from the lower end surface of the upper cover 3 (specifically, the lower end surface 31f of the extension portion 31) toward the lower side. The second outer wall guide portion 36 extends downward from the intermediate wall 32, and the guide surface 36f abutting on the inner peripheral surface of the outer wall 26 is inclined outward as it goes from the tip end side to the base end side. Further, when the lower case 2 and the upper cover 3 are fitted, the second outer wall guide portion 36 comes into contact with the inner peripheral surface of the outer wall 26 and presses and supports the outer wall 26 to the outside. In the upper cover 3, one second outer wall guide portion 36 is arranged between the two first outer wall guide portions 35 in the extension portion 31. The second outer wall guide portion 36 is provided integrally with the above-mentioned intermediate wall 32, and also serves as a reinforcing rib of the intermediate wall 32.

In addition, in the upper cover 3, the second inner wall guide portion 34 and the second outer wall guide portion 36 are displaced from each other in the direction along the intermediate wall 32. Specifically, the second inner wall guide portion 34 is arranged slightly forward, and the second outer wall guide portion 36 is arranged slightly rearward, whereby the second inner wall guide portion 34 and the second outer wall guide portion 36 are moved back and forth. It is displaced in the direction. However, the second inner wall guide portion 34 is arranged slightly rearward, and the second outer wall guide portion 36 is arranged slightly forward side, whereby the second inner wall guide portion 34 and the second outer wall guide portion 36 are displaced in the front-rear direction. You may let me. In any case, the second inner wall guide portion 34 is provided so as to fit inside the curved portion 321 (the inside of the portion inside the intermediate wall 32 and widened by the curved portion 321), and the second outer wall guide portion 36 is provided. Is integrally provided on the top of the curved portion 321.

Next, using FIGS. 11 and 12, the functions of the first inner wall guide portion 33 and the second inner wall guide portion 34 and the first outer wall guide portion 35 and the second outer wall when fitting the lower case 2 and the upper cover 3 are performed. The function of the guide unit 36 will be described. Here, FIG. 11 is a cross-sectional view of a position corresponding to the cross-sectional view taken along the line CC of FIG. 7. FIG. 12 is a cross-sectional view of a position corresponding to the cross-sectional view taken along the line DD of FIG. 7.

As shown in FIG. 11, when the lower case 2 and the upper cover 3 are brought close to each other, the upper end edge 25e of the inner wall 25 comes into contact with the guide surface 33f of the first inner wall guide portion 33. Since the guide surface 33f of the first inner wall guide portion 33 is inclined inward from the tip end side toward the base end side, the inner wall 25 is guided along the guide surface 33f.

After that, the upper end edge 25e of the inner wall 25 comes into contact with the guide surface 34f of the second inner wall guide portion 34 arranged inside the first inner wall guide portion 33. The guide surface 34f of the second inner wall guide portion 34 is inclined outward from the tip end side toward the base end side. Therefore, the inner wall 25 is sandwiched between the guide surface 33f of the first inner wall guide portion 33 and the guide surface 34f of the second inner wall guide portion 34. Since the inner wall 25 is sandwiched between two first inner wall guide portions 33 that press inward and one second inner wall guide portion 34 that is arranged between them and presses outward, the inner wall 25 is deformed to be slightly wavy. , It becomes completely immovable not only in the left-right direction but also in the front-back direction.

Similarly, as shown in FIG. 12, when the lower case 2 and the upper cover 3 are brought close to each other, the upper end edge 26e of the outer wall 26 comes into contact with the guide surface 35f of the first outer wall guide portion 35. Since the guide surface 35f of the first outer wall guide portion 35 is inclined inward from the tip end side to the base end side, the outer wall 26 is guided along the guide surface 35f.

After that, the upper end edge 26e of the outer wall 26 comes into contact with the guide surface 36f of the second outer wall guide portion 36 arranged inside the first outer wall guide portion 35. The guide surface 36f of the second outer wall guide portion 36 is inclined outward from the tip end side toward the base end side. Therefore, the outer wall 26 is sandwiched between the guide surface 35f of the first outer wall guide portion 35 and the guide surface 36f of the second outer wall guide portion 36. Since the outer wall 26 is sandwiched between two first outer wall guide portions 35 that press inward and one second outer wall guide portion 36 that is arranged between them and presses outward, the outer wall 26 is deformed to be slightly wavy. , It becomes completely immovable not only in the left-right direction but also in the front-back direction.

Further, after that, the locking claw 252 provided on the inner wall 25 is hooked on the locking hole 332 provided on the first inner wall guide portion 33, and the lower case 2 and the upper cover 3 are fixed in a fitted state. At this time, the upper end edge 25e of the inner wall 25 comes into contact with the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body portion 30), and the optimum contact pressure is secured. Further, the crushing rib 251 is crushed by this contact pressure. At the same time, the upper end edge 26e of the outer wall 26 also abuts on the lower end surface of the upper cover 3 (specifically, the lower end surface 31f of the extending portion 31), and the optimum contact pressure is secured. Further, the crushing rib 261 is crushed by this contact pressure.

Finally, the drip-proof sheet 8 of the electrical connection box 1 will be described. As shown in FIG. 1, the electrical connection box 1 includes at least a drip-proof sheet 8 that covers the upper surface of the upper cover 3. The drip-proof sheet 8 is a transparent polyolefin-based film. However, the color and material are not limited.

The drip-proof sheet 8 projects outward from the outer peripheral end of the upper cover 3. Specifically, it projects from the front end of the upper cover 3 to the upper side of the connector socket 5. In this respect, it may extend to the upper side of the connector 6 connected to the connector socket 5.

Further, the upper cover 3 also projects from the left end portion, the right end portion, and the rear end portion by a predetermined length. The portion of the upper cover 3 protruding from the left end portion is bent downward, and the bent piece 81 is attached to the outer peripheral surface of the inner wall 25 (specifically, the left wall portion 23). Similarly, the portion of the upper cover 3 protruding from the right end portion is also bent downward, and the bent piece 81 is attached to the outer peripheral surface of the outer wall 26. In the electrical connection box 1, the portion protruding from the rear end portion of the upper cover 3 extends toward the rear side. However, such a portion may also be bent downward and attached to the outer peripheral surface of the outer wall 26.

As described above, the electrical connection box 1 includes a resin lower case 2 that houses the circuit board 4 and a metal upper cover 3 that is fitted to the lower case 2 and closes the upper opening 2o of the lower case 2. A front opening 21o is provided in 2, a rear wall portion 22 facing the front opening 21o, and a pair of side wall portions (left wall portion 23, right wall portion) facing each other connected to each end side of the rear wall portion 22. 24) together, the inner wall 25 is formed, and the outer wall 26 is formed at a predetermined distance from a part of the inner wall 25 including the corner portion 2d of the rear wall portion 22 and the right wall portion 24. Then, the upper end edge 25e of the inner wall 25 comes into contact with the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body portion 30), and the upper end edge 26e of the outer wall 26 is located above the inner wall 25. The wall structure 27 is formed by connecting the lower end portions of the inner wall 25 and the outer wall 26 to provide a drainage passage 28 between the inner wall 25 and the outer wall 26.

According to such an electric connection box 1, high waterproof performance can be obtained.
More specifically, in the electrical connection box 1 according to the present invention, the upper end edge 25e of the inner wall 25 abuts on the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body 30) to provide predetermined waterproof performance. While ensuring, the upper end edge 26e of the outer wall 26 is located above the inner wall 25 to cover the fitting portion 10 (see FIGS. 9 and 10) of the lower case 2 and the upper cover 3, and the fitting portion 10 is covered with water. I try not to cover it directly. Further, in the electrical connection box 1 according to the present invention, the outer wall of the double wall structure 27 is covered with the outer wall 26 of the double wall structure 27 so as to wrap around the corner portion 2d and continuously cover the long fitting portion 10. It also prevents water from directly hitting the fitting portion 10 through the gap between the 26 and the outer wall 26. In addition, the electrical connection box 1 according to the present invention is provided with a drainage passage 28 between the inner wall 25 and the outer wall 26. Therefore, the water that has exceeded the outer wall 26 can be smoothly discharged, and the fitting portion 10 is not flooded. Therefore, high waterproof performance can be obtained.

Further, in the electrical connection box 1, the upper end edge 26e of the outer wall 26 is in contact with the lower end surface of the upper cover 3 (specifically, the lower end surface 31f of the extension portion 31).
According to such an electric connection box 1, it is possible to prevent the water that hits the side surface of the upper cover 3 and the like from entering the drainage passage 28 and the water that has traveled through the upper cover 3 from entering the drainage passage 28. can. Therefore, the amount of water entering the drainage passage 28 can be reduced, and the fitting portion 10 is not flooded. Therefore, high waterproof performance can be obtained.

Further, in the electrical connection box 1, one end side of the drainage passage 28 is opened and the other end side is closed.
According to such an electric connection box 1, in a long drainage passage 28 that is continuous so as to go around the corner portion 2d, the number of drainage ports 28o is one, so that it is difficult for water to directly hit the drainage port 28o. In this respect, if the drainage port 28o is provided on one end side shielded by the surrounding structure, the possibility that water directly hits the drainage port 28o can be further reduced. Therefore, water does not flow back from the drain port 28o, and the fitting portion 10 is not flooded. Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 is provided in the middle portion of the right wall portion 24 in which the opening end of the drainage passage 28 is separated from the corner portion 2c between the front opening 21o and the right wall portion 24.
According to such an electric connection box 1, since the drainage port 28o is provided at a position around the corner portion 2c from the front opening 21o, the drained water does not reach the front opening 21o. Further, the drained water does not splash on the connector socket 5 or the like inserted through the front opening 21o. Therefore, it is possible to prevent water from entering through the front opening 21o through the connector socket 5 and the like. Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 is provided in the middle portion of the rear wall portion 22 in which the closed end of the drainage passage 28 is separated from the corner portion 2b between the rear wall portion 22 and the left wall portion 23.
According to such an electrical connection box 1, the closed wall 29 that closes the drainage passage 28 is connected to the middle portion of the rear wall portion 22 that constitutes the inner wall 25, so that the rigidity of the inner wall 25 is improved. Therefore, the contact pressure between the upper end edge 25e of the inner wall 25 and the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body portion 30) can be secured, and the waterproof performance can be improved. Further, even if the water flowing back through the drainage passage 28 loses a place to escape and pushes the inner wall 25, it is possible to prevent the inner wall 25 from being distorted. As a result, it is possible to prevent the inner wall 25 from being distorted and a slight gap between the upper end edge 25e of the inner wall 25 and the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body 30). Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 has an intermediate wall 32 extending downward from the lower end surface of the upper cover 3, and the intermediate wall 32 is arranged between the inner wall 25 and the outer wall 26.
According to such an electrical connection box 1, an intermediate wall 32 extending downward is engaged between the inner wall 25 extending upward and the outer wall 26. Therefore, the infiltration route when water invades becomes long, and the waterproof performance can be improved. Further, since the outer wall 26 is supported from the inside by the intermediate wall 32, it is possible to prevent the outer wall 26 from being distorted even if water vigorously hits the outer wall 26 and pushes the outer wall 26. As a result, when the outer wall 26 is distorted, the width of the drainage passage 28 becomes small, and it is possible to prevent the smooth drainage from being hindered. Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 has a first inner wall guide portion 33 extending downward from the lower end surface of the upper cover 3 integrally with the intermediate wall 32, and the guide surface in the first inner wall guide portion 33. The 33f is inclined inward as it goes from the tip end side to the base end side, and presses and supports the inner wall 25 inward in a state of being in contact with the outer peripheral surface of the inner wall 25.

According to such an electric connection box 1, when the lower case 2 and the upper cover 3 are fitted in the assembly process of the electric connection box 1, the upper end edge 25e of the inner wall 25 is correct along the first inner wall guide portion 33. Can lead to a position. Therefore, the inner wall 25 and the intermediate wall 32 are correctly combined by one fitting operation. As a result, the assemblability of the electrical connection box 1 can be improved. Further, in the state where the lower case 2 and the upper cover 3 are fitted, the first inner wall guide portion 33 presses the inner wall 25 to regulate the displacement, so that the rigidity of the inner wall 25 is improved. Therefore, it is possible to prevent the inner wall 25 from being distorted and a slight gap between the upper end edge 25e of the inner wall 25 and the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body 30). Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 has a second inner wall guide portion 34 extending downward from the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body portion 30) inside the intermediate wall 32. The guide surface 34f in the second inner wall guide portion 34 is inclined outward as it goes from the tip end side to the base end side, and presses and supports the inner wall 25 outward in a state of being in contact with the inner peripheral surface of the inner wall 25. ..

According to such an electric connection box 1, when the lower case 2 and the upper cover 3 are fitted in the assembly process of the electric connection box 1, the upper end edge 25e of the inner wall 25 is correct along the second inner wall guide portion 34. Can lead to a position. Therefore, the inner wall 25 and the intermediate wall 32 are correctly combined by one fitting operation. As a result, the assemblability of the electrical connection box 1 can be improved. Further, in the state where the lower case 2 and the upper cover 3 are fitted, the second inner wall guide portion 34 presses the inner wall 25 to regulate the displacement, so that the rigidity of the inner wall 25 is improved. Therefore, it is possible to prevent the inner wall 25 from being distorted and a slight gap between the upper end edge 25e of the inner wall 25 and the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body 30). Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 has a first outer wall guide portion 35 extending downward from the lower end surface of the upper cover 3 (specifically, the lower end surface 31f of the extension portion 31) to the outside of the intermediate wall 32. The guide surface 35f in the first outer wall guide portion 35 is inclined inward from the tip end side to the base end side, and presses and supports the outer wall 26 inward in a state of being in contact with the outer peripheral surface of the outer wall 26. ..

According to such an electric connection box 1, when the lower case 2 and the upper cover 3 are fitted in the assembly process of the electric connection box 1, the upper end edge 26e of the outer wall 26 is correct along the first outer wall guide portion 35. Can lead to position. Therefore, the outer wall 26 and the intermediate wall 32 are correctly combined by one fitting operation. As a result, the assemblability of the electrical connection box 1 can be improved. Further, in the state where the lower case 2 and the upper cover 3 are fitted, the first outer wall guide portion 35 presses the outer wall 26 to regulate the displacement, so that the rigidity of the outer wall 26 is improved. Therefore, when the outer wall 26 is distorted, it is possible to prevent the passage width of the drainage passage 28 from becoming small and hindering smooth drainage. Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 is a second outer wall guide portion 36 extending downward from the lower end surface of the upper cover 3 (specifically, the lower end surface 31f of the extension portion 31) integrally with the intermediate wall 32. The guide surface 36f in the second outer wall guide portion 36 is inclined outward as it goes from the tip end side to the base end side, and presses and supports the outer wall 26 outward in a state of being in contact with the inner peripheral surface of the outer wall 26. do.

According to such an electric connection box 1, when the lower case 2 and the upper cover 3 are fitted in the assembly process of the electric connection box 1, the upper end edge 26e of the outer wall 26 is correct along the second outer wall guide portion 36. Can lead to position. Therefore, the outer wall 26 and the intermediate wall 32 are correctly combined by one fitting operation. As a result, the assemblability of the electrical connection box 1 can be improved. Further, in the state where the lower case 2 and the upper cover 3 are fitted, the second outer wall guide portion 36 presses the outer wall 26 to regulate the displacement, so that the rigidity of the outer wall 26 is improved. Therefore, when the outer wall 26 is distorted, it is possible to prevent the passage width of the drainage passage 28 from becoming small and hindering smooth drainage. Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 is provided with a curved portion 321 curved with respect to the virtual line L passing through the center of the inner wall 25 and the outer wall 26 in the middle portion of the intermediate wall 32.
According to such an electrical connection box 1, when the curved portion 321 that is raised outward is provided, the outer wall 26 is gently deformed along the curved surface, so that the outer wall 26 is pressed while being pressed against a specific outer wall 26. It is possible to prevent stress from concentrating in the region. On the contrary, when the curved portion 321 raised inward is provided, the inner wall 25 is gently deformed along the curved surface, so that the stress is concentrated on a specific region of the inner wall 25 while pressing the inner wall 25. Can be prevented. Further, since the passage width of the drainage passage 28 is regulated by the curved portion 321, it is possible to prevent the passage width of the drainage passage 28 from becoming small when the inner wall 25 and the outer wall 26 are distorted, which hinders smooth drainage. can. Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 has a second inner wall guide portion 34 that presses and supports the inner wall 25 to the outside in a state of being in contact with the inner peripheral surface of the inner wall 25, and an outer wall 26 in a state of being in contact with the inner peripheral surface of the outer wall 26. The second outer wall guide portion 36 and the second outer wall guide portion 36 are displaced with respect to each other in the direction along the intermediate wall 32.

According to such an electrical connection box 1, when the second outer wall guide portion 36 is displaced toward the rear wall portion 22 with respect to the second inner wall guide portion 34, the second outer wall guide portion 36 is provided from the drain port 28o in the drainage passage 28. (Ii) The outer wall guide portions 36 are separated from each other. Therefore, it is possible to prevent the smooth drainage of the water flowing while accelerating toward the drainage port 28o from being hindered. On the contrary, when the second outer wall guide portion 36 is displaced toward the front opening 21o with respect to the second inner wall guide portion 34, the second outer wall guide portion 36 is close to the drainage port 28o in the drainage passage 28. It will be. Therefore, it is possible to prevent water from flowing back from the drain port 28o. Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 is provided with a locking portion 11 that allows the inner wall 25 and the upper cover 3 to be locked.
According to such an electric connection box 1, the lower case 2 and the upper cover 3 can be fixed in a fitted state. Further, by locking the inner wall 25 and the upper cover 3 by the locking portion 11, it is possible to prevent the locking portion 11 from coming off even if the outer wall 26 is distorted due to vigorous water splashing on the outer wall 26. Further, when the locking portion 11 locks the inner wall 25 and the upper cover 3, the inner wall 25 is distorted and the upper end edge 25e of the inner wall 25 and the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body portion 30). It is possible to prevent a slight gap from being generated between the two. Therefore, high waterproof performance can be obtained.

Further, in the electrical connection box 1, the locking portion 11 is composed of a locking hole 332 and a locking claw 252 that hangs on the locking hole 332, and a portion of the inner wall 25 where the locking claw 252 is provided. The included region is formed thinner than the other regions.

According to such an electric connection box 1, when the lower case 2 and the upper cover 3 are fitted in the assembly process of the electric connection box 1, the portion of the inner wall 25 provided with the locking claw 252 is easily deformed. .. Therefore, the metal upper cover 3 side is easily locked with the locking hole 332. As a result, the assemblability of the electrical connection box 1 can be improved. Further, in the other regions of the inner wall 25, the inner wall 25 is thickly formed to ensure rigidity. Therefore, it is possible to prevent the inner wall 25 from being distorted and a slight gap between the upper end edge 25e of the inner wall 25 and the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body 30). Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 is provided with crushing ribs 251,261 on the upper end edge 25e of the inner wall 25 and the upper end edge 26e of the outer wall 26.
According to such an electric connection box 1, the lower case 2 and the upper cover 3 can be fixed without rattling. In particular, when the crushing rib 251 is provided on the upper end edge 25e of the inner wall 25, the lower end surface of the upper cover 3 (specifically, the lower end surface 30f of the main body 30) is provided around the crushing rib 251 at the upper end edge 25e of the inner wall 25. The contact pressure with and can be increased, and the waterproof performance can be improved. Therefore, high waterproof performance can be obtained.

Further, the electrical connection box 1 is provided with a drip-proof sheet 8 that covers the upper surface of the upper cover 3, and the drip-proof sheet 8 projects outward from the outer peripheral end portion of the upper cover 3.
According to such an electric connection box 1, it is possible to prevent the water that hits the side surface of the upper cover 3 and the like from entering the drainage passage 28 and the water that has traveled through the upper cover 3 from entering the drainage passage 28. can. Therefore, the amount of water entering the drainage passage 28 can be reduced, and the fitting portion 10 is not flooded. Therefore, high waterproof performance can be obtained.

Further, in the electrical connection box 1, the connector socket 5 is inserted through the front opening 21o, and the drip-proof sheet 8 projects to the upper side of the connector socket 5.
According to such an electric connection box 1, it is possible to prevent the water that hits the side surface of the upper cover 3 and the like from splashing on the connector socket 5 and the water that has traveled through the upper cover 3 from the connector socket 5. can. Therefore, it is possible to prevent water from entering through the front opening 21o through the connector socket 5 and the like. Therefore, high waterproof performance can be obtained.

Further, in the electrical connection box 1, the drip-proof sheet 8 is bent, and the left wall portion 23 and the right wall portion 24 are covered with the bent piece 81 of the drip-proof sheet 8.

According to such an electrical connection box 1, in the left wall portion 23 and the right wall portion 24 covered with the bent piece 81 of the drip-proof sheet 8, water directly reaches the fitting portion 10 of the lower case 2 and the upper cover 3. This can be reliably prevented. Further, in the left wall portion 23 and the right wall portion 24 covered with the bent piece 81 of the drip-proof sheet 8, the water that hits the side surface of the upper cover 3 and rebounds enters the drainage passage 28 and travels through the upper cover 3. It is possible to surely prevent the drained water from entering the drainage passage 28. Therefore, the amount of water entering the drainage passage 28 can be reliably reduced, and the fitting portion 10 is not flooded. Therefore, high waterproof performance can be obtained.

In the correspondence between the configuration of the present invention and the above-described embodiment, the electrical connection box of the present invention corresponds to the electrical connection box 1.
Similarly below
The lower case corresponds to the lower case 2
The upper cover corresponds to the upper cover 3 and
The circuit board corresponds to the circuit board 4,
The connector socket corresponds to the connector socket 5 and
The drip-proof sheet corresponds to the drip-proof sheet 8 and
The locking portion corresponds to the locking portion 11 and
The front wall part corresponds to the front wall part 21
The rear wall portion corresponds to the rear wall portion 22 and
The side wall portion corresponds to the left wall portion 23 and the right wall portion 24, and corresponds to the left wall portion 23.
The inner wall corresponds to the inner wall 25,
The outer wall corresponds to the outer wall 26,
The double wall structure corresponds to the double wall structure 27,
The drainage passage corresponds to the drainage passage 28,
The intermediate wall corresponds to the intermediate wall 32,
The first inner wall guide unit corresponds to the first inner wall guide unit 33,
The second inner wall guide unit corresponds to the second inner wall guide unit 34,
The first outer wall guide unit corresponds to the first outer wall guide unit 35,
The second outer wall guide unit corresponds to the second outer wall guide unit 36,
The crushed ribs on the inner wall correspond to the crushed ribs 251.
The locking claw corresponds to the locking claw 252,
The crushed ribs on the outer wall correspond to the crushed ribs 261.
The curved part corresponds to the curved part 321 and
The locking hole corresponds to the locking hole 332 and
The upper opening corresponds to the upper opening 2o,
The front opening corresponds to the front opening 21o,
The drainage port corresponds to the drainage port 28o,
The upper edge of the inner wall corresponds to the upper edge 25e,
The upper edge of the outer wall corresponds to the upper edge 26e,
The lower end surface of the upper cover corresponds to the lower end surface 30f and the lower end surface 31f.
The virtual line corresponds to the virtual line L, and the present invention is not limited to the configuration of the above-described embodiment, and many embodiments can be obtained.

As shown in FIG. 4, in the main electrical connection box 1, the lower case 2 has an outer wall 26 so as to cover the rear wall portion 22, the right wall portion 24, and the corner portion 2d connecting the both wall portions 22, 24. It is configured. Therefore, the outer wall 26 has an L-shape with the corner portion 2d as a curved angle when viewed from above.

In this regard, as shown in FIG. 13, the outer wall 26 may be configured so as to cover the rear wall portion 22, the left wall portion 23, and the corner portion 2b connecting the both wall portions 22, 23. In this case, the outer wall 26 has an L-shape with the corner portion 2b as a curved angle when viewed from above. It is considered that the same effect can be obtained in such an embodiment.

Alternatively, as shown in FIG. 14, the wall portion 22, the left wall portion 23, the right wall portion 24, the corner portion 2b connecting both wall portions 22, 23, and the corner portion 2d connecting both wall portions 22, 24. The outer wall 26 may be configured to cover and. In this case, the outer wall 26 has a U-shape with the corners 2b and 2d as the corners when viewed from above. It is considered that the same effect can be obtained in such an embodiment.

1 ... Electrical connection box 2 ... Lower cover 3 ... Upper cover 4 ... Circuit board 5 ... Connector socket 8 ... Drip-proof sheet 11 ... Locking part 21 ... Front wall part 22 ... Rear wall part 23 ... Left wall part 24 ... Right wall part 25 ... Inner wall 26 ... Outer wall 27 ... Double wall structure 28 ... Drainage passage 32 ... Intermediate wall 33 ... First inner wall guide part 34 ... Second inner wall guide part 35 ... First outer wall guide part 36 ... Second outer wall guide part 251 ... Crushing rib 252 ... Locking claw 261 ... Crushing rib 321 ... Curved portion 332 ... Locking hole 2o ... Upper opening 21o ... Front opening 28o ... Drainage port 25e ... Upper end edge of inner wall 26e ... Upper end edge of outer wall 30f ... Upper cover Lower end surface 31f ... Lower end surface L of the upper cover ... Virtual line

Claims (18)

A resin lower case that houses the circuit board,
It is provided with a metal upper cover that is fitted to the lower case and closes the upper opening of the lower case.
The lower case is provided with a front opening, and an inner wall is formed by a rear wall portion facing the front opening and a pair of side wall portions facing each other connected to each end of the rear wall portion. An outer wall is formed at a predetermined distance from a part of the inner wall including a corner portion between the portion and at least one of the side wall portions.
The upper end edge of the inner wall abuts on the lower end surface of the upper cover, and the upper end edge of the outer wall is located above the inner wall to form a double wall structure.
An electrical connection box in which a drainage passage is provided between the inner wall and the outer wall by connecting the inner wall and the lower end portion of the outer wall. The electrical connection box according to claim 1, wherein the upper end edge of the outer wall abuts on the lower end surface of the upper cover. The electrical connection box according to claim 1 or 2, wherein one end side of the drainage passage is opened and the other end side is closed. The electrical connection box according to claim 3, wherein the opening end of the drainage passage is provided in the middle portion of the side wall portion separated from the corner portion between the front opening and the side wall portion. The closed end of the drainage passage is provided in the corner portion between the rear wall portion and the side wall portion, and in the rear wall portion or the middle portion of the side wall portion separated from the corner portion between the front opening and the side wall portion. The electrical connection box according to claim 3 or 4. The invention according to any one of claims 1 to 5, which has an intermediate wall extending downward from the lower end surface of the upper cover, and the intermediate wall is arranged between the inner wall and the outer wall. Electrical junction box. It has a first inner wall guide portion extending downward from the lower end surface of the upper cover integrally with the intermediate wall.
The guide surface in the first inner wall guide portion is inclined inward from the tip end side to the base end side.
The electrical connection box according to claim 6, wherein the inner wall is pressed and supported inward in a state of being in contact with the outer peripheral surface of the inner wall. It has a second inner wall guide portion extending downward from the lower end surface of the upper cover inside the intermediate wall.
The guide surface in the second inner wall guide portion is inclined outward as it goes from the tip end side to the base end side.
The electrical connection box according to claim 6 or 7, wherein the inner wall is pressed and supported outward in a state of being in contact with the inner peripheral surface of the inner wall. It has a first outer wall guide portion extending downward from the lower end surface of the upper cover to the outside of the intermediate wall.
The guide surface in the first outer wall guide portion is inclined inward from the tip end side to the base end side.
The electrical connection box according to any one of claims 6 to 8, wherein the outer wall is pressed and supported inward in a state of being in contact with the outer peripheral surface of the outer wall. It has a second outer wall guide portion that extends downward from the lower end surface of the upper cover integrally with the intermediate wall.
The guide surface in the second outer wall guide portion is inclined outward as it goes from the tip end side to the base end side.
The electrical connection box according to any one of claims 6 to 9, wherein the outer wall is pressed and supported outward in a state of being in contact with the inner peripheral surface of the outer wall. The electrical connection box according to claim 6, wherein a curved portion curved with respect to a virtual line passing through the center of the inner wall and the outer wall is provided in the middle portion of the intermediate wall. A second inner wall guide portion that presses and supports the inner wall to the outside in a state of being in contact with the inner peripheral surface of the inner wall.
It has a second outer wall guide portion that presses and supports the outer wall to the outside in a state of being in contact with the inner peripheral surface of the outer wall.
The electrical connection box according to claim 6, wherein the second inner wall guide portion and the second outer wall guide portion are displaced from each other in a direction along the intermediate wall. The electrical connection box according to any one of claims 1 to 12, wherein a locking portion that allows the inner wall and the upper cover to be locked is provided. The locking portion is composed of a locking hole and a locking claw that hangs on the locking hole.
The electrical connection box according to claim 13, wherein the region including the locking hole or the portion provided with the locking claw on the inner wall is formed thinner than the other region. The electrical connection box according to claim 1, wherein a crushing rib is provided on at least one of the upper end edge of the inner wall and the upper end edge of the outer wall. A drip-proof sheet that covers the upper surface of the upper cover is provided.
The electrical connection box according to any one of claims 1 to 15, wherein the drip-proof sheet projects outward from the outer peripheral end portion of the upper cover. A connector socket is inserted through the front opening,
The electrical connection box according to claim 16, wherein the drip-proof sheet projects to the upper side of the connector socket. The drip-proof sheet is bent and
The electrical connection box according to claim 16 or 17, wherein at least one of the side wall portion and the rear wall portion is covered with a bent piece in the drip-proof sheet.

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