JP3324511B2 - Fixing structure of electrical junction box - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing structure of an electric connection box, and more particularly, to a fixing structure using bolts and nuts when attaching the electric connection box to a vehicle body or when assembling an upper case and a lower case of the electric connection box. But
It is intended to maintain the fastening force between the bolt and the nut even after long-term use.

[0002]

2. Description of the Related Art When an electric junction box made of resin is mounted on a vehicle body such as an automobile, the fastening force of a mounting bolt is received by a contact surface of the electric junction box with the bolt, but the contact surface is made of resin. If the tightening torque of the bolts is increased, the electrical connection box may be bent or cracked, and the electric connection box may be damaged. Further, due to aging of the electric connection box or vibration of the vehicle body due to heat of the engine or the like, the fastening force of the bolt is likely to be lower than the initial value, and in the worst case, the bolt may be completely loosened.

[0003] Also, when assembling the upper case and the lower case of the electric junction box, since both cases are made of resin, the same thing as described above may occur. Therefore, it is necessary to prevent the fastening force of the bolt from being applied to the contact surface of the electrical junction box with the bolt, and to maintain the fastening force of the bolt.

FIG. 6 shows a cross section of a portion of the conventional electric junction box attached to the vehicle body. Bolt holes 1a provided in the resin case 1 of the electric junction box are slightly smaller than the thickness of the resin case 1. A long metal ring 2 is press-fitted, a bolt 4 fitted with a washer 3 is inserted through the ring 2 and screwed into a nut 6 welded to a vehicle body panel 5.

In the above configuration, the fastening force of the bolt 4 by screwing with the nut 6 is not applied to the resin case 1 of the electric connection box, but to the end face of the ring 2.
The bolt 4, the washer 3 and the ring 2 are all made of metal. Therefore, the bolt 4 should be tightened more securely than before, and the bolt and nut should be securely fastened. Can be. In addition, the ring 2 can be used also in an assembly portion of the upper case and the lower case of the electric connection box in the same manner as described above.

[0006]

However, since the ring 2 is press-fitted into the resin case 1 of the electric connection box as a separate part, the number of parts increases, and the press-fitting point is a part of the electric connection box attached to the vehicle body. Since the number of assembled parts of the upper case and the lower case is large, the number of manufacturing steps of the electric junction box increases, and the manufacturing cost increases.

[0007] The present invention has been made in view of the above problems, and without increasing the number of manufacturing steps of the electric junction box,
It is an object of the present invention to prevent a bolt fastening force from being applied to a resin case of an electrical junction box and to maintain the bolt fastening force.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, first, according to the present invention, a metal nut is welded to a body fixing side of a vehicle body having a bolt hole so as to surround the bolt hole. The ring part is made to protrude integrally from the peripheral edge of the central female screw hole in the nut, and the ring part has the same outer diameter in the axial direction, and the ring part is penetrated through the resin case of the electric connection box. Press-fit into the provided bolt hole and slightly project from the bolt insertion surface of the bolt hole of the case,
The inner diameter of the ring portion is larger than the shaft diameter of the bolt, and the shaft portion of the bolt is screwed into the center female screw hole through the ring portion of the nut. The present invention provides a fixing structure for an electric junction box which is configured to abut against an end face of the electrical junction box and not to abut a resin case.

With the above construction, since the ring portion protruding from the metal nut welded to the vehicle body is projected from the resin case on the bolt insertion side, the head of the mounting bolt inserted through the ring portion is provided. Abuts against the end face of the ring portion and does not abut against the resin case. Therefore, no bolt fastening force is applied to the resin case, and no bending or the like occurs.

Further, since the bolt and the ring are made of metal, the tightening torque of the bolt can be increased as compared with the conventional art, and the bolt and the nut can be securely fastened and fixed. Further, since the ring portion is formed as an integral part by projecting from the nut, the number of parts does not increase.

A second aspect of the present invention is a fixing structure of an electric connection box for simultaneously fixing resin cases forming the electric connection box and fixing the electric connection box to a vehicle body, comprising: A metal nut is welded and fixed to the electric junction box fixed side of the vehicle body so as to surround the bolt hole, and a ring portion is integrally protruded from the peripheral edge of the central female screw hole to the nut, and the same outer diameter in the axial direction. In a state where the bolt holes provided through the resin case of the electric connection box are communicated with each other, the ring portion is pressed into the bolt holes and slightly protrudes from the bolt insertion surface of the bolt holes, and The inner diameter of the ring portion is made larger than the shaft diameter of the bolt, and the shaft portion of the bolt is screwed into the central female screw hole through the ring portion of the nut. Tree in contact with the end face It provides a fixing structure of the electric connection box has a configuration that does not contact the manufacturing case.

As described above, the upper case and the lower case constituting the electric junction box are assembled, and the two cases are fixed to the vehicle body at the same time when the two cases are fixed to the vehicle body.
By projecting the ring part on the metal nut to be welded to the car body, the tightening torque of the bolt is increased without applying the fastening force of the bolt to the resin case of the electric connection box,
It can be securely screwed to the nut.

The third aspect of the present invention is a fixing structure of an electric connection box for fixing a resin case of an electric connection box to be mounted on an automobile with bolts and nuts. On the other hand, a metal nut is embedded and fixed in the other case, and a ring portion is integrally protruded from the peripheral edge of the central female screw hole in the nut, and the ring has the same outer diameter in the axial direction. Part is press-fitted into the bolt hole of the other case, and slightly protrudes from the bolt insertion surface of the bolt hole, and the inner diameter of the ring part is larger than the shaft diameter of the bolt. Provided is a fixing structure of an electric junction box, wherein the nut is screwed into the center female screw hole through a ring portion, and a head portion of the bolt abuts on an end surface of the ring portion and does not abut a resin case in a fastened state. There.

As described above, also at the part where the electric junction box is to be assembled, a bolt hole is made to penetrate the upper case which is one case, and a metal nut is embedded and fixed in the lower case which is the other case. The ring part is projected from the nut. Press the ring part into the bolt hole of the upper case, assemble the upper case and the lower case,
Even if the bolts are fastened and fixed, no bolt fastening force is applied to the two cases of the electric connection box, and the fastening is ensured because the bolt tightening torque can be increased.

[0015]

FIG. 1 shows a state in which an electric connection box D of the present invention is fixed to a vehicle body S. FIG. 2 shows a first embodiment of the present invention, in which a fixing portion A of an electric connection box D to a vehicle body S in FIG.
2 shows a cross section of FIG. The electric connection box D is composed of an upper case 10 and a lower case 11, which are resin cases. The lower case 11 is provided with a bolt hole 11a for inserting a bolt 40 for fixing to a vehicle body. The inner diameter of the bolt hole 11a is determined by a ring portion 60a of a nut 60 described later.
It is set to almost the same size as the outside diameter of.

The lower case 11 is usually provided with three or more bolt holes 11a.
It is not necessary to set the inside diameter of the ring portion 1a to at least one of the bolt holes 11a as described above.
The inner diameter of the bolt may be set to be substantially the same as the outer diameter of the bolt, and the other bolt holes may be larger than the above inner diameter. The thickness of the lower case 11 at the portion where the bolt holes 11a are provided is T.

The fixing bolt 40 passes through the washer 30 through the shaft portion to increase the contact area serving as a contact portion when the bolt 40 is tightened. The bolt used is not limited to the shape shown in FIG. 2, and for example, a flanged bolt or the like may be used, and the washer 30 is not necessarily used.

The metal nut 60 shown in FIG. 3 has a ring portion 60a projecting from the periphery of the female screw hole 60b so as to be concentric with the female screw hole 60b. The inner diameter of the ring portion 60a is slightly larger than the shaft diameter of the bolt 40, and
To make it easier to insert. As shown, the ring portion 60a has the same outer diameter in the axial direction, and the length H is set to be slightly longer than the plate thickness T of the bolt hole 11a of the lower case 11.

As shown in FIG. 2, the nut 60 has a side surface facing the ring portion 60a at a required position on the vehicle body panel 50 and is fixed by welding. Note that the vehicle body panel 50 is provided with a through hole 50 a having an inner diameter larger than the shaft diameter of the bolt 40, concentric with the female screw hole 60 b of the fixed nut 60.

When the electric connection box D is mounted on the vehicle body S, the bolt hole 11a of the lower case 11 of the electric connection box D is fitted into the ring portion 60a of the nut 60 welded to the vehicle body. Since the outer diameter of the ring portion 60a is substantially the same as that of the ring portion 60a, press fitting is performed, and the electric connection box D is mounted without play.

At the time of press-fitting, one surface 11 of the lower case 11
The lower case 11 is pushed in until the b contacts the side surface 60c of the nut 60, and the plate thickness T of the lower case 11 and the length H of the ring portion 60a satisfy the relationship of H> T. Bolt insertion surface 1 of lower case 11
1c slightly protrudes.

As described above, after the electric connection box D is mounted on the vehicle body S, the bolt 40 passing through the washer 30 is inserted into the ring portion 60a, the tightening torque is increased, and the electric connection box D is fastened to the nut 60, and the electric connection box D is tightened. The connection box D is completely fixed to the vehicle body S. In the above-mentioned fastening state, since the ring portion 60a protrudes from the lower case 11, the head of the bolt 40 contacts the end face 60b of the ring portion 60a via the washer 30,
It does not contact the lower case 11 of the electric connection box. Therefore, the fastening force of the bolt 40 is not applied to the lower case 11,
It is hung on the ring part 60a.

As described above, since the ring portion 60a receiving the fastening force of the bolt 40 is made of metal,
Can be coped with even when the tightening torque increases, and when the tightening torque increases, the tightening force between the bolt 40 and the nut 60 also increases, so that the above-described tightening force can be maintained even against vibration of the vehicle body and the like. Further, since the fastening force of the bolt 40 is not applied to the lower case 11, bending or cracking due to the load of the fastening force does not occur.

If only a part of the bolt hole 11a of the lower case 11 is set to have an inner diameter that matches the press-fitting, and the other bolt holes have an inner diameter larger than the above-mentioned press-fitting, the bolt hole is formed in the ring portion. Since only a part is press-fitted, the mounting of the lower case 11 of the electric junction box D to the vehicle body S becomes even easier, and since a part is press-fitted, there is no play in mounting the electric connection box D. Does not occur.

FIG. 4 shows a second embodiment, and shows a cross section of a fixing portion B for simultaneously fixing the electric connection box D to the case and mounting the electric connection box D to the vehicle body in FIG. Electrical junction box D
The upper case 10 and the lower case 11 are assembled and fixed to each other by bolt holes 10a, 11
d is provided respectively. The inner diameters of the bolt holes 10a and 11d are set in the same manner as in the first embodiment.

Nut 60 'welded to body panel 50'
Is provided with a ring portion 60a 'as in the first embodiment, and the length H' of the ring portion 60a 'is set slightly longer than the thickness T' of the assembly portion of the upper case 10 and the lower case 11. In order to mount the electric junction box D on the vehicle body, the bolt holes 10a and 11d of both cases are press-fitted into the ring portion 60a 'in a state where the upper case 10 is attached to the lower case 11 and assembled. Same as the form.

The fastening state of the bolt 40 'and the nut 60' is the same as in the first embodiment. Since the ring portion 60a 'slightly projects from the upper case 10, the head of the bolt 40' is interposed via the washer 30 '. End face 60b 'of ring portion 60a'
But not with the upper case 10. Therefore, in the upper case 10 and the lower case 11,
No bending or the like occurs, and the bolt 40 'is securely fastened.

FIG. 5 shows a third embodiment, and shows a cross section of an assembly portion C of the upper case 10 and the lower case 11 of the electric connection box D in FIG. Upper case 10
Has a bolt hole 10c as in the first embodiment, and the lower case 11 has a metal nut 60 ″ embedded and fixed at a position corresponding to the bolt hole 10c.

Similarly to the first embodiment, the nut 60 "has a ring portion 60a" protruding therefrom, and the length of the ring portion H ".
Is set to be slightly longer than the thickness T ″ of the upper case 10. To assemble the electric junction box D, cover the upper case 10 with the lower case 11 and attach the bolt holes 10 c.
Into the ring portion 60a ″.
The distal end of Oa "projects from the upper surface of the upper case 10 and is fastened and fixed with bolts 40" in the same manner as in the first embodiment.

In the above-mentioned fastening state, the bolt 40 "abuts on the end face of the ring portion 60a" via the washer 30 "due to the slight protrusion of the ring portion 60a", but does not abut on the upper case 10.

[0031]

As described above, by projecting the ring portion on the nut, the fastening force of the bolt can be received by the ring portion, and even if the tightening torque of the bolt is increased, it is possible to cope with the increase. The fastening force is increased, and the fastening force can be maintained even after long-term use. In addition, by maintaining the fastening force, the electrical junction box can be securely fixed to the vehicle body, and the upper and lower cases of the electrical junction box can be securely fixed. Can be raised.

Further, since no bolt fastening force is applied to the resin case, no bending or the like is generated, and the burden on the resin case can be reduced. Further, since the ring portion is integrated with the nut, it has various advantages such that the number of parts is not increased and the manufacturing process of the electric junction box does not need to be changed from the conventional one.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which an electric junction box according to an embodiment of the present invention is fixed to a vehicle body.

FIG. 2 is a schematic cross-sectional view illustrating a first embodiment of the present invention and illustrating a portion A in FIG. 1;

FIG. 3 is a perspective view of a nut used in the present invention.

FIG. 4 is a schematic cross-sectional view showing a second embodiment of the present invention and showing a portion B in FIG. 1;

FIG. 5 is a schematic sectional view showing a third embodiment of the present invention and showing a portion C in FIG. 1;

FIG. 6 is a schematic cross-sectional view showing a fixing portion between a conventional electric junction box and a vehicle body.

[Explanation of symbols]

 4, 40, 40 ', 40 "bolt 6, 60, 60', 60" nut 10 Upper case 11 Lower case 5, 50, 50 'Body panel 60a, 60a', 60a "Ring D Electrical connection box

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H02G 3/08 F16B 5/02 F16B 37/06

Claims (3)

(57) [Claims] 1. An electric junction box fixed to a vehicle body provided with bolt holes.
Metal nut welded around the bolt hole on the side
The ring part is integrated with the nut from the periphery of the center female screw hole.
And the ring part has the same outer diameter in the axial direction.
And penetrate the ring portion into the resin case of the electric connection box.
And press-fit into the bolt holes provided.
Project slightly from the bolt insertion surface of the hole, and
The inside diameter of the part is larger than the shaft diameter of the bolt, and the shaft part of the bolt is passed through the ring
A fixing structure for an electric connection box, wherein the bolt is screwed together with a female screw hole, and in a fastened state, the head of the bolt comes into contact with the end face of the ring portion and does not come into contact with the resin case. 2. The fixing of the resin cases forming the electric connection box and the fixing of the electric connection box to the vehicle body are performed simultaneously.
An electric junction box fixing structure, in which a bolt hole is provided on the electric junction box fixing side of a vehicle body provided with a bolt hole.
A metal nut is welded and fixed so as to surround it, and the ring part is integrated with the above nut from the periphery of the central female screw hole.
And the ring part has the same outer diameter in the axial direction.
And a bolt provided through the resin case of the electric connection box.
With the holes in communication, press the ring part into the bolt holes.
And slightly project from the bolt insertion surface of the bolt hole.
And the inner diameter of the ring portion is larger than the shaft diameter of the bolt.
Make the shaft of the bolt bigger and pass the center of the bolt through the ring of the nut.
A fixing structure for an electric connection box, wherein the bolt is screwed together with a female screw hole, and in a fastened state, the head of the bolt comes into contact with the end face of the ring portion and does not come into contact with the resin case. 3. An electric junction box mounted on an automobile made of resin.
Secure the electrical junction box that secures the cases with bolts and nuts.
It has a fixed structure, with one case penetrating the bolt hole and the other
Embed a metal nut in one of the cases and fix it.
Make the ring part protrude integrally from the periphery of the central female screw hole
At the same time, the ring portion has the same outer diameter in the axial direction, and the ring portion is pressed into the bolt hole of the other case.
Both protrude slightly from the bolt insertion surface of the bolt hole,
The inner diameter of the ring is larger than the shaft diameter of the bolt.
And pass the bolt shaft through the nut ring through the center
A fixing structure for an electric connection box, wherein the bolt is screwed together with a female screw hole, and in a fastened state, the head of the bolt comes into contact with the end face of the ring portion and does not come into contact with the resin case.