JP7120852B2 - Electrical Junction Box and Wire Harness - Google Patents

Description

TECHNICAL FIELD The present invention relates to an electric junction box mounted on an automobile. The present invention also relates to a wire harness provided with this electric connection box and routed in an automobile.

An example of an electric device mounted on an automobile is an electric connection box. The electrical connection box is known as a general term for a relay box, a fuse box, a junction block, and the like. A conventional electrical connection box (see Patent Document 1 below) will be briefly described below.

A conventional electrical connection box is configured by including an electronic component block and a housing for housing the electronic component block. The electronic component block is assembled with a plurality of electrical components and is formed in such a state that the electrical components are connected to a predetermined circuit. On the other hand, the housing includes a frame to which the electronic component block is assembled and fixed, an upper cover that covers an upper opening of the frame, and a lower cover that covers a lower opening of the frame.

When the upper opening and lower opening of the frame are covered with the upper cover and the lower cover, respectively, the joints of the covers and the joints of the frame are engaged with each other to provide a waterproof structure against moisture from the outside. It is formed. The waterproof structure is formed by engaging the joints so that the walls of the joints face each other with a minute gap as if they were in contact with each other. Therefore, even when water is applied from the outside of the electric connection box, the water does not reach the inside of the electric connection box.

JP 2010-130705 A

In the prior art described above, there is a risk that when the engaging portion of the joint portion of the frame and the joint portion of the upper cover is strongly exposed to water due to, for example, high-pressure washing, the water may enter the minute gap. If water flows in the extending direction of the joint (peripheral direction of the frame), depending on the location, the momentum of the flow may cause the water to blow out toward the inner side of the electric junction box. Concerned. The inventor of the present application believes that there is room for improvement in the waterproof structure.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrical connection box and a wire harness capable of improving the waterproof structure.

The electrical connection box of the present invention, which is described in claim 1, is provided to solve the above-mentioned problems, and includes a frame peripheral wall having a double wall structure having an outer wall and an inner wall, and a cover covering an opening surrounded by the frame peripheral wall. The frame peripheral wall is formed in a shape having a frame-side joint portion with respect to the cover at the ends of the outer wall and the inner wall near the opening, and the cover is formed with the frame-side joint portion When the cover is an upper cover, the frame-side joint portion has a frame-side stepped portion and a first engagement wall that is continuous with the outer wall. , a second engagement wall continuous with the inner wall is formed, and the cover-side seam portion includes a third engagement wall disposed outside the first engagement wall, and the first engagement wall. A fourth engagement wall inserted between the wall and the second engagement wall, and a connecting portion connecting the third engagement wall and the fourth engagement wall so as to straddle the first engagement wall. and a notch-shaped frame-side slit or a through-hole-shaped frame-side hole is formed in the first engaging wall. a fifth engaging wall continuing to the outer wall and a sixth engaging wall continuing to the inner wall are formed; A seventh engagement wall inserted between the joint wall and the sixth engagement wall is formed, and the seventh engagement wall has a notch-shaped cover-side slit or a through-hole-shaped cover-side hole. The frame-side slit, the frame-side hole, the cover-side slit, or the cover-side hole is formed to prevent moisture from entering the engaging portion of the frame-side joint portion and the cover-side joint portion. , is arranged and formed in the middle of a water channel that is generated in the circumferential direction of the frame peripheral wall.

According to the present invention having such a feature of claim 1, water from the outside of the electric junction box is applied to the periphery of the engagement portion between the frame-side joint and the cover-side joint under strong pressure, and the water is absorbed into the joint. When it enters a minute gap between the walls of the frame and flows in the extending direction of the joint (the circumferential direction of the frame peripheral wall), the force of the flow is loosened by the slit or the hole. Specifically, when water enters the minute gap and flows through the water channel in the extending direction of the joint (the circumferential direction of the frame peripheral wall) and reaches the slit or hole, the cross-sectional area of the water channel suddenly increases. It is the same condition as if it had entered into a part that has become larger, so that the pressure of the water is weakened at the position of the slit or hole. That is, the force of water flowing through the water channel is relieved by the slits or holes. When the momentum is relaxed, the force that tries to enter the next waterway is weakened, and as a result, the blowout of moisture toward the side closer to the inside of the electrical connection box is suppressed. Therefore, according to the present invention, the waterproof structure can be improved. In addition, in the present invention, even one slit or hole is effective, and if a plurality of slits or holes are formed, the momentum of moisture can be significantly weakened. Some (or all) of the moisture reaching the slits or holes is dropped, for example, between the outer wall and the inner wall, and is drained to the outside of the electrical connection box by appropriate means.

The present invention according to claim 2 is the electrical connection box according to claim 1, wherein the frame-side slit is cut out from the tip of the first engagement wall to the base end where the frame-side stepped portion continues. characterized by being formed

The present invention according to claim 3 is the electrical connection box according to claim 1, wherein the cover-side slit is cut from the tip of the seventh engagement wall to the base end where the cover-side stepped portion continues. characterized by being formed

According to the present invention having the features of claims 2 and 3 as described above, since the slit is formed by notching up to the base end, the cross-sectional area of the water channel can be maximized. This can effectively weaken the water pressure. Incidentally, in the case of a hole, it may be formed so as to pass through including the position of the base end. In this case as well, since the formation is at a position where water easily flows, the pressure of water can be effectively weakened. Supplementing with respect to the holes, they have the advantage that the strength of the walls can be ensured more than slits.

A wire harness according to claim 4 of the present invention, which has been made to solve the above-mentioned problems, is provided with the electric connection box according to claim 1, 2 or 3 at the terminal and is routed in an automobile. Characterized by

According to the present invention having such a feature of claim 4, it is possible to provide a wire harness in which the waterproof structure of the electric connection box is improved.

ADVANTAGE OF THE INVENTION According to the electric-connection box of this invention, it is effective in the ability to improve a waterproof structure. Moreover, according to the wire harness of this invention, it is effective in the ability to provide a better thing.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows one Embodiment of the electrical-connection box of this invention (Example 1). FIG. 2 is a perspective view showing the frame of FIG. 1; 3 is an enlarged view of circle A in FIG. 2; FIG. It is a figure which shows the modification of FIG. FIG. 4 is a cross-sectional view showing a frame-side joint portion and a cover-side joint portion at a position where a frame-side slit is present; FIG. 4 is a cross-sectional view showing a frame-side joint portion and a cover-side joint portion at a position where a frame-side slit is present; FIG. 4 is a cross-sectional view showing a frame-side joint portion and a cover-side joint portion; FIG. 4 is a cross-sectional view showing a frame-side joint portion and a cover-side joint portion; It is a figure which shows the flow of water|moisture content typically. FIG. 10 is a diagram showing a frame-side joint portion and a cover-side joint portion, where (a) is a cross-sectional view at a position where there is a cover-side slit, and (b) is a cross-sectional view at a position where there is no cover-side slit (Embodiment 2). ).

An electrical connection box provided at the end of a wire harness is configured with a frame peripheral wall having a double wall structure having an outer wall and an inner wall, and a cover that covers an opening surrounded by the frame peripheral wall. The frame peripheral wall is formed into a shape having frame-side joints with the cover at the ends of the outer and inner walls near the opening. The cover is also shaped to have a cover-side seam that engages the frame-side seam. The engaging portions of the frame-side joint portion and the cover-side joint portion are formed into a shape having a slit or a hole. The slit or hole is formed in the middle of a water channel that is generated in the peripheral direction of the frame peripheral wall when water enters the engaging portion.

The first embodiment will be described below with reference to the drawings. FIG. 1 is a perspective view showing one embodiment of the electrical connection box of the present invention. 2 is a perspective view showing the frame in FIG. 1, FIG. 3 is an enlarged view of circle A in FIG. 2, FIG. 4 is a diagram showing a modification of FIG. 3, and FIGS. 7 and 8 are cross-sectional views showing the frame-side joint and the cover-side joint, and FIG. 9 is a diagram schematically showing the flow of water. . In the drawings, an arrow P indicates a vertical direction, an arrow Q indicates a horizontal direction, and an arrow R indicates a front-rear direction.

<Regarding the electrical connection box 1>
In FIG. 1, an electric connection box 1 is mounted on a vehicle such as an automobile or a truck in a state of being provided at a terminal at a predetermined position of a wire harness (not shown). Such an electric connection box 1 is configured by including an electronic component block (not shown) and a housing 2 for accommodating the electronic component block. It should be noted that the appearance of the electrical connection box 1 is an example.

As will be understood from the following description, the electric junction box 1 has an improved waterproof structure compared to the conventional one. In other words, the electric connection box 1 has a waterproof structure (a waterproof structure that suppresses the blowout of water so that the electronic component block is prevented from being sprayed with water). structure). First, the constituent members of the electric connection box 1 will be described.

<About the electronic component block>
An electronic component block (not shown) is provided as a member to which a plurality of electronic components are assembled. Also, the electronic component block is provided as a member to which the electronic component is connected to a predetermined circuit. Specifically, for example, a relay is assembled to a resin relay assembly portion, and a fuse is provided as a member to be assembled to a resin fuse assembly portion (this is an example). The electronic component block as described above is of a cassette type and is formed so as to be detachably attached to an attachment portion (reference numerals omitted) of the frame 3, which will be described later. As for the electronic component block, this name may be read as a cassette block.

<About housing 2>
In FIG. 1, the housing 2 is a combination of resin members having insulating properties. 4 (opening); lower cover 7 (cover) covering lower opening 6 (opening) of frame 3; side covers 8 and 9 assembled to one side of frame 3; configured with Such a housing 2 is formed with a protruding through portion 10 through which a wire bundle of a wire harness (not shown) is pulled out (inserted).

<About frame 3>
In FIGS. 1 and 2, the frame 3 is a resin molded product, and includes a frame peripheral wall 11, a fixed leg portion 12 provided outside the frame peripheral wall 11, and a fixed base 13 similarly provided outside the frame peripheral wall 11. , and a plurality of mounting portions (reference numerals omitted) provided inside the frame peripheral wall 11 to detachably mount an electronic component block (not shown). The frame 3 is formed in a rectangular frame-like member with top and bottom openings. The upper opening of frame 3 is formed as upper opening 4 . Also, the opening on the lower side of the frame 3 is formed as a lower opening 6 . The fixed leg portion 12 is formed as a fixed portion when the electric connection box 1 is mounted on the vehicle. A through hole 14 is formed in the fixing leg 12 for fastening to the vehicle with a bolt. A pair of projection engaging portions 15 each having a rectangular through-hole shape is formed on the fixed base 13 . The pair of protrusion engaging portions 15 are formed as portions that become the center of rotation when the upper cover 5 is attached.

<Regarding the frame peripheral wall 11>
1, 2, 5, 6, 7, and 8, the frame peripheral wall 11 includes a rectangular frame-shaped outer wall 16 and a rectangular frame-shaped inner wall 17 disposed inside the outer wall 16. It is formed into a double-walled structure having a Further, the frame peripheral wall 11 includes a plurality of connecting portions 18 for connecting and arranging the outer wall 16 and the inner wall 17 at predetermined intervals, a frame-side locking portion 19 for locking the upper cover 5, and the lower cover 7. It has a plurality of frame-side locking portions 20 for locking and is formed into the illustrated shape.

The outer wall 16 and the inner wall 17 are each formed by four walls (the number of walls is one example), although no particular reference numerals are attached. Specifically, it is formed by a front wall and a rear wall in the direction of arrow R, and a left wall and a right wall in the direction of arrow Q. A frame-side joint portion 21 to the upper cover 5 is formed at the upper ends of the outer wall 16 and the inner wall 17 . A frame-side joint portion 22 to the lower cover 7 is formed at the lower ends of the outer wall 16 and the inner wall 17 . Note that the frame-side joint portion 22 for the lower cover 7 will be described in the second embodiment.

<Regarding the frame-side joint 21>
5 to 8, the frame-side joint portion 21 is formed with a first engaging wall 23 continuing to the outer wall 16 and a second engaging wall 24 continuing to the inner wall 17. As shown in FIGS. The first engagement wall 23 has a frame-side stepped portion 25 that continues to the upper end of the outer wall 16, and a wall body 26 that continues to the frame-side stepped portion 25 and projects straight upward, and has a substantially L-shaped cross section. formed in The first engaging wall 23 is formed so that the substantially L-shaped cross section continues in the extending direction of the frame-side joint portion 21 (the circumferential direction of the frame peripheral wall 11). The frame-side stepped portion 25 is formed at a portion of the upper cover 5 with which the lower end of a third engaging wall 34 described later abuts. The first engaging wall 23 is arranged and formed so that the wall main body 26 is close to the second engaging wall 24 side due to the presence of the frame-side stepped portion 25 . The second engagement wall 24 is formed as a wall portion that projects straight upward from the upper end of the inner wall 17 . In the frame-side seam portion 21 as described above, one or a plurality of frame-side slits 27, which is a feature of the present invention, are formed.

<Regarding the frame-side slit 27>
2, 3, 5 and 6, the frame side slit 27 is formed in the wall body 26 of the first engagement wall 23. As shown in FIG. The frame-side slit 27 is formed so as to cut straight from the tip (upper end) of the wall body 26 to the base end where the frame-side stepped portion 25 is continuous. It is optional whether or not the notch extends to the base end. It is preferable to be absent. In addition, the cutout width of the frame-side slit 27 is set to a suitable size. One or a plurality of frame-side slits 27 are arranged in the middle of the water channel 39 . If there is a position on the electric connection box 1 that is likely to be exposed to water during high-pressure washing, for example, the frame-side slit 27 is preferably arranged and formed at a position slightly deviated from this position.

<About the frame side hole 28>
In FIG. 4, reference numeral 28 indicates a frame side hole. This frame side hole 28 is a modified example of the frame side slit 27 in FIG. The frame-side hole 28 is formed in such a shape that a bridge portion is added to the upper end of the frame-side slit 27 . In the present invention, frame-side holes 28 may be employed instead of frame-side slits 27 .

<Regarding the upper cover 5>
In FIG. 1, the upper cover 5 is a resin molded product for covering the upper opening 4 of the frame 3 as described above. 3, and a cover-side locking portion 32 provided on the opposite side of the pair of projections 31, and formed into the illustrated shape. The upper cover 5 is formed so as to be a member separate from the frame 3 . The cover peripheral wall 30 is formed short in the vertical direction of the arrow P in this embodiment. A cover-side seam portion 33 is formed at the lower end of such a short cover peripheral wall 30 .

<Regarding the cover-side seam 33>
5 to 8, the cover-side joint portion 33 is formed at a portion that engages with the frame-side joint portion 21. As shown in FIG. Specifically, a third engaging wall 34 arranged outside the first engaging wall 23 of the frame peripheral wall 11 and a fourth engaging wall 34 inserted between the first engaging wall 23 and the second engaging wall 24 It has a joint wall 35 and a connecting portion 36 that connects the third engaging wall 34 and the fourth engaging wall 35 so as to straddle the first engaging wall 23, so that the cover side seam portion 33 as shown in the drawing is formed. It is formed. The third engagement wall 34 is formed such that its inner surface faces the outer surface of the first engagement wall 23 . The lower end of the third engaging wall 34 is formed as a contact portion of the frame-side stepped portion 25 . A stepped portion 37 that protrudes outward from the lower end and a skirt portion 38 that protrudes downward from the stepped portion 37 are formed in the third engaging wall 34 as described above. The third engagement wall 34 is formed into a substantially crank-shaped cross section when viewed including the stepped portion 37 and the skirt portion 38 . The cover-side joint portion 33 is formed such that the wall or the like extends in the same direction as the frame-side joint portion 21 .

<About Waterway 39>
In FIGS. 5 to 8, moisture that has entered from between the outer surface of the outer wall 16 and the inner surface of the skirt portion 38 due to, for example, high-pressure washing is removed from the outer surface of the first engaging wall 23 and the inner surface of the third engaging wall 34. When it reaches the minute gap between them, it spreads in the direction of the arrow (same as the circumferential direction of the frame peripheral wall 11) due to capillary action, so that the minute gap functions as a water channel 39. FIG.

In the conventional example, if the force of the water flowing through the water channel 39 is strong, it may hit the corner portion 40 (see FIG. 2), for example, and the water may blow upward at this time. However, as can be seen from the above description, the present invention has a structure capable of suppressing the blowout of water so as to prevent the water from blowing onto an electronic component block (not shown). The operation of the structure will be described below.

<About the action of the frame-side slit 27 (frame-side hole 28)>
In FIG. 9, when water flows through the channel 39, the force of the flow is reduced by the frame-side slit 27 (frame-side hole 28) (see the thickness of the arrows in the drawing). Specifically, when the water flowing through the channel 39 reaches the frame-side slit 27 (frame-side hole 28), it is in the same state as if the water channel 39 had entered a portion where the cross-sectional area suddenly increased. As a result, the moisture pressure is weakened at the position of the frame-side slit 27 (frame-side hole 28). That is, the force of the water flowing through the water channel 39 is relieved by the frame-side slits 27 (frame-side holes 28). When the momentum is relaxed, the force to enter the next water channel 39 is weakened, and as a result, the blowout of water to the electronic component block (not shown) is suppressed.

<About the effect of the electrical connection box 1>
As described above with reference to FIGS. 1 to 9, according to the electrical junction box 1 of one embodiment of the present invention, it is possible to suppress the blowout of moisture as described above. Therefore, there is an effect that the waterproof structure can be improved as compared with the conventional example.

<About the effect of the wire harness>
Moreover, since the wire harness (not shown) is provided with the electrical connection box 1 at the terminal, it is possible to provide a better wire harness.

The second embodiment will be described below with reference to the drawings. 10A and 10B are diagrams showing the frame-side joint portion and the cover-side joint portion, where (a) is a cross-sectional view at a position with a cover-side slit, and (b) is a cross-sectional view at a position without a cover-side slit. Components that are basically the same as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

<Regarding the frame-side joint portion 22>
In FIG. 10 , the frame-side joint portion 22 is formed with a fifth engaging wall 41 continuing to the outer wall 16 and a sixth engaging wall 42 continuing to the inner wall 17 . The fifth engaging wall 41 and the sixth engaging wall 42 are formed as walls extending straight downward. Also, the fifth engaging wall 41 and the sixth engaging wall 42 are formed so that their ends are located at the same position. Such a frame-side joint portion 22 is formed as a joint portion with respect to the lower cover 7 constituting the electric junction box 1 (see FIG. 1).

<Regarding the lower cover 7 and the cover-side seam 44>
In FIG. 10 , a cover-side seam portion 44 is formed at the upper end of the cover peripheral wall 43 of the lower cover 7 . The cover-side joint portion 44 is formed at a portion that engages with the frame-side joint portion 22 . A seventh engaging wall 46 having a cover-side stepped portion 45 and inserted between the fifth engaging wall 41 and the sixth engaging wall 42 is formed in the cover-side joint portion 44 . The cover-side stepped portion 45 is formed in a shape protruding outward as a portion with which the end portion of the fifth engaging wall 41 abuts. In addition, in the minute gap between the inner surface of the fifth engaging wall 41 and the outer surface of the seventh engaging wall 46, a channel similar to that of the first embodiment is formed, although no particular reference numerals or arrows are attached. .

A cover-side slit 47 (or a cover-side hole) is formed in the seventh engagement wall 46 so as to be in the middle of the water channel. The cover-side slits 47 have the same function as the frame-side slits 27 (see FIG. 3) of the first embodiment to weaken the momentum of water (detailed description is omitted here). The cover-side slit 47 is formed in the same shape as the frame-side slit 27 . Moisture reaching the bottom wall of the lower cover 7 through the cover-side slit 47 is drained to the outside through a drain hole (not shown).

In addition, it goes without saying that the present invention can be modified in various ways without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1... Electrical junction box 2... Housing 3... Frame 4... Upper opening (opening) 5... Upper cover (cover) 6... Lower opening (opening) 7... Lower cover (cover) 8, 9... Side cover 10... Through part 11... Frame peripheral wall 12... Fixed leg part 13... Fixed base 14... Through hole 15... Projection engagement part 16... Outer wall 17... Inner wall 18... Connecting portion 19 Frame side lock portion 20 Frame side lock portion 21, 22 Frame side joint portion 23 First engagement wall 24 Second engagement wall 25 Frame side stepped portion 26 ...Wall body 27...Frame side slit 28...Frame side hole 29...Ceiling wall 30...Cover peripheral wall 31...Protrusion 32...Cover side lock part 33...Cover side joint part 34...Third engagement Wall 35... Fourth engagement wall 36... Connection part 37... Stepped part 38... Skirt part 39... Water channel 40... Corner part 41... Fifth engagement wall 42... Sixth engagement wall, 43... Cover peripheral wall 44... Cover side seam 45... Cover side stepped portion 46... Seventh engaging wall 47... Cover side slit

Claims (4)

comprising a frame peripheral wall having a double wall structure having an outer wall and an inner wall, and a cover covering an opening surrounded by the frame peripheral wall,
The frame peripheral wall is formed in a shape having frame-side joints with the cover at ends of the outer wall and the inner wall near the opening,
the cover is formed in a shape having a cover-side joint portion that engages with the frame-side joint portion;
When the cover is an upper cover, the frame-side joint portion is formed with a first engaging wall having a frame-side stepped portion and continuing to the outer wall, and a second engaging wall continuing to the inner wall. and, at the cover-side seam portion, a third engagement wall arranged outside the first engagement wall, and a third engagement wall inserted between the first engagement wall and the second engagement wall Four engagement walls and a connecting portion connecting the third engagement wall and the fourth engagement wall so as to straddle the first engagement wall are formed, and the first engagement wall includes: While a notch-shaped frame-side slit or a through-hole-shaped frame-side hole is formed,
When the cover is a lower cover, the frame side joint portion is formed with a fifth engagement wall continuing to the outer wall and a sixth engagement wall continuing to the inner wall, and the cover side joint portion is formed with a seventh engagement wall that has a cover-side stepped portion and is inserted between the fifth engagement wall and the sixth engagement wall, and the seventh engagement wall has a cut A notch-shaped cover-side slit or a through-hole-shaped cover-side hole is formed,
The frame-side slit, the frame-side hole, the cover-side slit, or the cover-side hole is designed to prevent moisture from entering the engaging portion of the frame-side joint portion and the cover-side joint portion. An electrical connection box, characterized by being arranged and formed in the middle of a water channel that is generated in the circumferential direction of a peripheral wall. In the electrical connection box according to claim 1,
The electrical connection box, wherein the frame-side slit is formed by notching from the tip of the first engagement wall to the base end where the frame-side stepped portion is continuous. In the electrical connection box according to claim 1,
The electrical junction box, wherein the cover-side slit is formed by notching from the distal end of the seventh engagement wall to the base end where the cover-side stepped portion continues. A wire harness comprising the electrical connection box according to claim 1, 2 or 3 at a terminal thereof and routed in a vehicle.

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