JP2000316219A - Electric connection box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of backlash in the engaging state of the cover of an electric connection box with its main-body case. SOLUTION: A peripheral wall 12b of a cover 12 of an electric connection box 10 is formed doubly out of an inner cover wall 13-1 and an outer cover wall 13-2, and a peripheral wall 14b of a main-body case 14 of the electric connection box 10 is formed double out of an inner main-body wall 15-2 and an outer case wall 15-1 to protrude an elastic piece 17 obliquely downward from an inside wall surface 15-1a of the outer case wall 15-1. After interposing the inner cover wall 13-1 between the outer case wall 15-1 and the inner main- body wall 15-2, by contacting the elastic piece 17 with the inner cover wall 13-1 to deflect the elastic piece 17, the inner cover wall 13-1 and the outer case wall 15-1 are deflected respectively to eliminate clearances S1, S2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric junction box, and more particularly, to a waterproof electric junction box.
It is intended to enhance the ease of fitting between the cover and the main body case and to suppress the occurrence of play in the fitted state.

[0002]

2. Description of the Related Art An electric junction box mounted in an engine room or the like of an automobile includes a main body case for accommodating a bus bar and the like constituting an internal circuit and a cover. On the upper and lower surfaces of the main body case and the like, a large number of connection portions for the internal circuit and the external circuit are provided. The cover is fitted and covered.

FIG. 4A and FIG.
5 is a waterproof structure of an electric junction box proposed in No. 5. The peripheral wall 2b of the cover 2 of the electric junction box 1 is constituted by double cover walls 3-1, 2. On the other hand, body case 4
The main body is formed of a double main body wall 5-1, 2 and a drain hole 6 is provided in a main body horizontal portion 4d connecting between the main body walls 5-1, 2. When the cover 2 is fitted to the main body case 4, the cover walls 3-1 and 2-1 and the main body walls 5-1 and 2 are alternately fitted to form a fitting portion 9 to prevent water from entering. In addition, even if the water enters beyond the cover wall 3-2 or the like, water is drained from the drain hole 6.

In addition to the above, a waterproof structure for an electric junction box has been proposed in Japanese Utility Model Application Laid-Open No. 63-118274 shown in FIGS. 5 (A), 5 (B) and 5 (C). Step 2 is provided at the lower end of cover 2 'covering the upper surface of case 4'.
d 'and the lower peripheral wall 2e' are provided on the entire circumference, and an elastic flexible wall 7 'is provided on the entire circumference vertically below the inside of the cover 2' of the step 2d '. When the cover 2 'is fitted to the main body case 4', the elastic flexible wall 7 'is connected to the upper peripheral edge 4a' of the main body case 4 'and the lower peripheral wall 2 of the cover 2'.
It is fitted in a space 8 'between the space e' and the space 8 'so as to be waterproof.

[0005]

In the cover 2 of the electric connection box 1 and the fitting portion 9 of the main body case 4 shown in FIGS. 4A and 4B, if the dimensions of the fitting portions are the same, the fitting is performed. Therefore, it is necessary to provide some clearance. Specifically, the distance D1 between the main body walls 5-1 and 5-2 of the main body case 4 is set to the cover wall 3 inside the cover 2.
1 and a clearance D larger than the thickness T1 by about 0.2 mm and a distance D between the cover walls 3-1 and 3-2.
2 is also larger than the thickness T2 of the outer body wall 5-1. By these clearances, the cover 2 and the main body case 4 can be fitted smoothly. However, in the fitted state, the clearance becomes an amount of play, and there is a problem that play occurs in the X direction in the figure. There is also a problem that water is easily immersed by the play amount. Further, since the distance D1 between the main body walls 5-1 and 2 is larger than the thickness T1 of the cover wall 3-1 only by the amount of the clearance, there is a problem that the alignment at the time of fitting is difficult and the fitting takes time.

[0006] In order to solve the above-mentioned problem, there is a case where the packing is fitted between the cover 2 and the main body case 4 so as to increase waterproofness and to suppress generation of backlash. However, the use of the packing increases the cost of the packing, increases the number of steps required for mounting the packing, and increases the cost and labor required for manufacturing the electrical junction box.

On the other hand, in the electric junction box 1 'shown in FIGS. 5A, 5B and 5C, the elastic flexible wall 7' is inserted into the space 8 'in the fitted state.
By being fitted over the entire circumference, waterproofness is ensured and rattling is suppressed. However, since the elastic flexible wall 7 ′ is shorter than the lower peripheral wall 2 e ′ and is located inside the lower peripheral wall 2 e ′, it is difficult to externally check the distal end position of the elastic flexible wall 7 ′. There is a problem that it is difficult to align the tip of the elastic flexible wall 7 'with the upper peripheral edge 4a' of the main body case 4 '. Further, as shown in FIG. 5 (C), the distal end of the elastic flexible wall 7 ′ is expanded outward so as to fit into the space 8 ′, so that the elastic flexible wall 7 ′ that cannot be confirmed from the outside can be reliably secured over the entire circumference. It is very difficult work to fit into the fitting, and there is a problem that the fitting work requires time and effort.

The present invention has been made in view of the above-described problem, and has as its first object to prevent rattling when a cover and a main body case are fitted to each other. A second object is to facilitate fitting of the cover and the main body case.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an electric connection in which a cover is put on a main body case accommodating an internal circuit, and a peripheral wall of the cover is fitted to and assembled with the peripheral wall of the main body case. In the box, the peripheral wall of the cover is
An inner cover wall extending below the peripheral edge of the upper surface of the cover, and an outer cover wall connected by a horizontal portion protruding from an outer wall surface of the inner cover wall and positioned at an interval outside the inner cover wall; The peripheral wall of the main body case is connected to the inner main body wall of the peripheral edge by a main body horizontal portion protruding from the outer wall surface of the inner main body wall, and is located at an interval outside the inner main body wall. The inner case wall is made up of an outer case wall and an elastic piece protruding from one of the outer wall surface of the inner cover wall and the inner wall surface of the outer case wall. An electric connection box is provided, wherein the electric connection box is configured to be fitted between a wall and the elastic piece to abut against an opposing wall surface to fit the cover and the main body case.

Thus, the cover and the main body case are
By making the elastic piece protrude from one of the wall surfaces of the cover and the main body case as well as the heavy wall, when the cover and the main body case are fitted, the elastic piece comes into contact with the opposing wall surface and bends. The wall having a wall surface which is in contact with this elastic piece,
It bends in the opposite direction to the side where the elastic piece is located, and abuts against the wall located on the flexure side, while the wall with the elastic piece also flexes in the opposite direction to the side where the elastic piece is located and lies on the flexure side. Abut,
The existence of the gap due to the clearance in the fitted state can be eliminated. By eliminating the clearance, the occurrence of backlash can be reliably prevented, and the sealing performance is also improved, so that the waterproofness can be ensured. In consideration of the moldability of the mold, it is preferable that the elastic piece protrudes above a drain hole provided for drainage in a horizontal portion of the main body.

In addition, there is a space between the inner cover wall and the outer cover wall of the cover and between the inner body wall and the outer case wall of the main body case so as to secure the projection size of the elastic piece. The thickness of each of the walls to be fitted is wider than that of the other, so that the walls can be easily fitted, and the cover and the main body case can be easily fitted. The number of walls constituting the cover and the peripheral wall of the main body case may be more than two.

It is preferable that the elastic piece projects obliquely downward from the inner wall surface of the outer case wall and abuts on the outer wall surface of the opposing inner cover wall. As described above, by projecting the elastic piece obliquely downward from the inner wall surface of the outer case wall, the elastic piece can guide the inner cover wall and fit smoothly without hindering the fitting of the cover. Also, at the time of fitting, the inner wall surface of the outer cover wall and the outer wall surface of the outer case wall, and the inner wall surface of the inner cover wall and the outer wall surface of the inner main body wall are respectively in contact with each other.

Further, the present invention provides an electric junction box in which a cover is put on a main body case accommodating an internal circuit, and the peripheral wall of the cover is fitted to and assembled with the peripheral wall of the main body case. A cover wall extending below the peripheral portion, wherein the peripheral wall of the main body case is connected to an inner main body wall of the peripheral portion by a main body horizontal portion protruding from an outer wall surface of the internal main body wall; The outer wall of the outer case is spaced apart from the outer case wall, and the elastic piece is projected obliquely downward from the inner wall surface of the outer case wall. The electric connection box is provided so as to be fitted between the case wall and the elastic piece to abut against the outer wall surface of the opposing cover wall to fit the cover and the main body case. That.

As described above, the peripheral wall of the cover is constituted by only one wall, and the peripheral wall of the main body case is constituted by a double wall. The inner wall and the outer wall of the inner body wall abut,
As in the above case, the occurrence of backlash can be prevented. Further, the elastic piece may be made to protrude from the cover wall on the cover side instead of the main body case side.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1A, 1B, and 1C show a fitting portion 19 of the electric connection box 10 according to the first embodiment of the present invention. The electric connection box 10 is formed by fitting a body case 14 for accommodating a bus bar (not shown) made of resin and accommodating a bus bar (not shown) and a cover 12 and fitting them together.

The cover 12 is formed so as to cover the upper surface of the main body case 14, and the peripheral wall 12b is composed of double inner and outer cover walls 13-1 and 13-2. Specifically, the inner cover wall 13-1 extends downward continuously from the peripheral edge 12e of the upper surface 12a of the cover 12. The outer cover wall 13-2 is the outer wall surface 13 of the inner cover wall 13-1.
-1b, they are connected to each other at a protruding end portion 12d of the horizontal portion 12c and protrude downward, and are spaced apart from the inner cover wall 13-1.

The inner and outer cover walls 13-1 and 13-2 are flexible and have a height and a thickness T3 sufficient to protect the fitting portion 19. The dimension T3 is set to 1.5 mm. The distance D3 between the inner cover wall 13-1 and the outer cover wall 13-2 is
The thickness is set in consideration of the thickness T4 of the outer case wall 15-1 of the main body case 14 described later, the amount of protrusion of the elastic piece 17, and the clearance required for fitting. In the present embodiment, the clearance is set to 0.2 mm. It is set to 2 mm.

On the other hand, the main body case 14 is configured so as to be vertically divided into two parts in a box shape for accommodating a bus bar therein. The peripheral wall 14b of the main body case 14 has an internal main body wall 15-2 located on the peripheral edge 14e of the case upper part 14c.
And the outer case wall 15-1 which is connected to the main body horizontal portion 14d protruding from the outer wall surface 15-2b of the inner main body wall 15-2 and is spaced outside the inner main body wall 15-2 to be doubled. Make up. The outer case wall 15-1 and the inner body wall 15-2 also have flexibility, and have a height and a thickness T4 in consideration of protection. In the present embodiment, the thickness T4 is 2.0 mm. Is set to In the horizontal part 14d of the main body, drainage holes 16 for drainage are provided at appropriate intervals in the circumferential direction.

Further, the elastic piece 17 projects obliquely downward from the inner wall surface 15-1a of the outer case wall 15-1. The elastic piece 17 is made of resin and has flexibility. In the present embodiment, the protrusion height is set to about 3 mm and the width is set to 5 mm, and the elastic piece 17 is bent with the protrusion base 17a as a fulcrum.
The distance D4 between the outer case wall 15-1 having the elastic piece 17 and the inner main body wall 15-2 is determined in this embodiment in order to secure the protrusion height of the elastic piece and the clearance required for fitting. It is set to 3.7 mm. The locations where the elastic pieces 17 are provided are provided at appropriate intervals in the circumferential direction in consideration of the vertical and horizontal dimensions of the main body case 14 and the like. It is preferable to provide it above the drain hole 16 in consideration of removal.

In order to fit the cover 12 into the main body case 14, as shown in FIG. 1B, the cover 12 covers the upper surface of the main body case 14 and the inner main body wall 15-2.
Between the inner case wall 15-1 and the outer case wall 15-1
And the inner and outer cover walls 13-1,
2, the outer case wall 15-1 is fitted. At this time, the dimension D between the inner and outer cover walls 13-1 and 13-2
3 is about twice the thickness T4 of the outer case wall 15-1, and similarly, the outer case wall 15-1 and the inner main body wall 15-1.
2 is also the thickness T3 of the inner cover wall 13-1.
Since it is about twice as large as the above, it can be easily fitted to a required position without paying particular attention to the fitting position of each wall.

At the time of the fitting, the dimensions D3 and D4 between the inner and outer cover walls 13-1, 2 and the like include dimensions including the clearance, so that the inner wall surface 13-1a of the inner cover wall 13-1 and the inner main body wall. 15-2 outer wall surface 15-
2b, a gap S1 is generated due to clearance.
Similarly, a gap S2 is generated between the inner wall surface 13-2a of the outer cover wall 13-2 and the outer wall surface 15-1b of the outer case wall 15-1. Since the wall surfaces do not come into contact with each other due to the gaps S1 and S2, there is no resistance, so that the fitting can be performed easily and smoothly also in this respect.

From the above state, as shown in FIG.
When the cover 12 is fitted downward to be in the fitted state, the elastic pieces 17 are opposed to the outer wall surface 13 of the inner cover wall 13-1.
-1b, and bends downward about the projecting base 17a.
At the time of the fitting, the elastic piece 17 projects obliquely downward, so that the elastic piece 17 is smoothly guided downward without hindering the fitting of the inner cover wall 13-1. The elastic piece 17
The elastic piece 17 and the outer wall surface 13-1 act as a reaction to the deflection of
A force F1 for pressing the inner cover wall 13-1 inwardly acts on the abutting portion b, while a force F2 for bending the outer case wall 15-1 itself outwardly acts on the protruding base 17a.

The inner cover wall 13-1 is bent inward by the force F1, and the inner wall surface 13-1a and the inner main body wall 15-1 are bent.
2 and comes into close contact with the outer wall surface 15-2b, thereby eliminating the existence of the gap S1. Similarly, the outer case wall 15-1 bends outward due to the force F2, and the outer wall surface 15-1b comes into contact with the inner wall surface 13-2a of the outer cover wall 13-2 to come into close contact therewith, thereby eliminating the existence of the gap S2. ing. As described above, in the state where the cover 12 and the main body case 14 are fitted together, there is no gap S1 or S2 due to the clearance, so that no play occurs.
Furthermore, the opposing wall surfaces at the two locations are in close contact with each other, so that the sealing property is enhanced and the waterproof property is improved.

FIG. 2 shows a fitting portion 19 'of an electric connection box 10' according to a modification of the first embodiment, in which an elastic piece 17 'is projected toward the cover 12'. Cover 1
2 ′ has substantially the same shape and dimensions as those of the first embodiment, and the peripheral wall 12b ′ has inner and outer cover walls 13-1 ′,
It is doubled at 2 '. This inner cover wall 13-
An elastic piece 17 'protrudes from the outer wall surface 13-1b' of 1 '. This elastic piece 17 'is the elastic piece 1 of the first embodiment.
7 and the like, but the projection direction is different from that of the elastic piece 17 and projects obliquely upward. This is because the elastic piece 17 'does not hinder the cover 1
This is for smoothly fitting 2 '.

On the other hand, the main body case 14 'is substantially the same as the main body case 14 of the first embodiment from which the elastic pieces 17 are removed, and has the same dimensions and the like. Also, the inner body wall 15
The height of -2 'may be higher than in the first embodiment. When the cover 12 'and the main body case 14' are fitted, the elastic piece 17 'is moved to the inner wall surface 15-1 of the outer case wall 15-1'.
a ′ and bends with the protruding base 17a ′ as a fulcrum. Due to the reaction of this bending, the outer case wall 15-1 '
Bends outward, comes into contact with and adheres to the outer cover wall 13-2 ', and similarly the inner cover wall 13-1' and the inner body wall 15
-2 'also adheres, preventing rattling and increasing waterproofness.

FIG. 3 shows a fitting portion 19 "of the electric connection box 10" according to the second embodiment of the present invention. The peripheral wall 12b "of the cover 12" of the electric connection box 10 "is formed around the cover upper surface 12a". One cover wall 13 "extending below the end 12e"
This is the case with only The dimensions and the like of the cover wall 13 "are equivalent to the inner cover wall 13 of the first embodiment. On the other hand, the peripheral wall 14b" of the main body case 14 "is substantially equivalent to the peripheral wall 14b of the first embodiment, and the outer case wall. 15-1 "and the inner main body wall 15-2", and the elastic piece 1 is formed from the inner wall surface 15-1a "of the outer case wall 15-1".
7 ". The outer case wall 15-1"
In consideration of the fact that the cover 12 "is composed of only the cover wall 13", the projecting base 17a 'of the elastic piece 17' is used.
The outer case wall 15-1 "does not extend upward.

When the cover 12 "and the body case 14" are fitted together, the elastic piece 17 "abuts on the outer wall surface 13a" of the cover wall 13 "to bend with the protruding base 17a" as a fulcrum, and the cover wall 13 ". As a result, the cover wall 13 "and the inner main body wall 15-2" come into contact with each other and come into close contact with each other to suppress the occurrence of backlash and to ensure waterproofness. Wall 15-1 "and internal body wall 1
Since the distance between 5-2 "and the thickness of the cover wall 13" has a margin as in the first embodiment, it can be easily fitted.

In the present invention, various deformation patterns other than the first and second embodiments described above are possible, and the cover wall, the main body wall and the like may have a double or more multiplex structure.
Also, a plurality of elastic pieces may be provided. further,
In addition to the case where the upper surface of the main body case is covered with the cover, the structure of the fitting portion of the present invention is applicable to a structure where the lower surface of the main body case is covered with the cover.

[0029]

As is evident from the above description, the use of the electric connection box of the present invention does not cause backlash and provides waterproofness even when the cover and the main body case are provided with clearance. Can be enhanced. In addition, regarding the fitting between the cover and the main body case, in addition to providing the required clearance, the distance between the walls is wider than the thickness of the fitted wall, so that the required positioning of the fitted wall can be easily performed. Thus, the cover can be easily fitted to the main body case.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a fitting portion in an electric connection box according to a first embodiment of the present invention, where (A) is a state before fitting and (B).
Shows a state during fitting, and (C) shows a fitted state.

FIG. 2 is a cross-sectional view of a fitting portion showing a fitting state of a modification of the first embodiment.

FIG. 3 is a cross-sectional view of a fitting portion showing a fitting state of the electric connection box of the second embodiment.

FIG. 4 is a sectional view of a fitting portion of a conventional electric connection box;
(A) shows a state before fitting, and (B) shows a fitted state.

5 (A) is a perspective view, FIG. 5 (B) is a sectional view of a fitting portion before fitting, and FIG. 5 (C) is a sectional view of a fitted state.

[Explanation of symbols]

 1, 10, 10 ', 10 "electrical junction box 2, 12, 12', 12" cover 2b, 12b, 12b ', 12b "peripheral wall 3-1, 13-1 inner cover wall 3-2, 13-2 external Cover wall 4, 14, 14 ', 14 "body case 5-1, 15-1 outer case wall 5-2, 15-2 inner body wall 17, 17', 17" elastic piece

Claims (3)

[Claims] 1. An electric connection box in which a cover is put on a main body case accommodating an internal circuit and a peripheral wall of the cover is fitted to and assembled with a peripheral wall of the main body case, wherein the peripheral wall of the cover is lower than a peripheral edge of an upper surface of the cover. The main body is formed by an inner cover wall extending to the inner cover wall and an outer cover wall connected by a horizontal portion protruding from an outer wall surface of the inner cover wall and positioned at an interval outside the inner cover wall. The peripheral wall of the case is doubled by an inner main body wall at a peripheral edge portion and an outer case wall connected by a main body horizontal portion protruding from an outer wall surface of the inner main body wall and spaced apart outside the inner main body wall. An elastic piece is protruded from one of the outer wall surface of the inner cover wall and the inner wall surface of the outer case wall to form the inner cover wall into the inner body wall and the outer case wall. Are fitted in between the electrical connection box, characterized in that is brought into contact with the wall surface facing the elastic piece has a configuration of fitting the cover and the main body case. 2. The electric connection box according to claim 1, wherein the elastic piece projects obliquely downward from an inner wall surface of the outer case wall and abuts on an outer wall surface of the inner cover wall facing the elastic case. 3. An electric connection box in which a cover is put on a main body case accommodating an internal circuit, and a peripheral wall of the cover is fitted to and assembled with a peripheral wall of the main body case, wherein the peripheral wall of the cover is lower than a peripheral edge of an upper surface of the cover. The peripheral wall of the main body case is connected to an inner main body wall of a peripheral portion and a main body horizontal portion protruding from an outer wall surface of the inner main body wall, and is spaced outside the inner main body wall. And the outer case wall is separated from the inner case wall, and the elastic piece is projected obliquely downward from the inner wall surface of the outer case wall. An electric connection box, wherein the elastic piece is fitted into a space between the cover wall and the outer wall surface of the opposing cover wall to fit the cover and the main body case.