JPH08167339A - Grommet - Google Patents

Abstract

PURPOSE: To improve waterproof and attaching strength to a wall in a grommet, prevent damage by the tip of a burring hole and attach to the wall even when a burring angle is different. CONSTITUTION: A grommet has a circular engaging groove 18 for engaging with an edge part 17b of a through hole 17a formed in a wall 17, a large diameter part 13 in which a first inserting hole 13a for loosely inserting a wire harness is formed, and a small diameter part 14 protruding from the large diameter part 13, in which a second inserting hole 14a communicating with the first inserting hole 13a is formed. A first lip 22 is formed at the outer end of a first side wall 20 of the engaging groove 18. A circular first recess 23 is formed in the first side wall 20, and a second lip 24 is formed between the first recess 23 and a bottom wall 19 of the engaging groove 18. A third lip 26 is formed at the tip of the second side wall 21 of the engaging groove 18. The first lip and the third lip are overlapped each other. A circular housing groove 25 is formed in a connecting part of the bottom wall to the second side wall.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grommet which is mounted in a through hole for inserting a wire harness provided in a wall portion of a vehicle body of an automobile or a panel of equipment, and more particularly, it has improved waterproofness and mounting strength, and The present invention relates to prevention of damage when the burring type through-hole is mounted.

[0002]

2. Description of the Related Art In a wire harness for an automobile, when the wire harness is inserted through a through hole provided in a wall portion of a vehicle body or a panel of equipment, the wire harness is previously inserted through a grommet made of an elastic material. The grommet is attached to the through hole in this state for waterproofing.

For example, Japanese Unexamined Patent Publication No. 4-249817 discloses a grommet as shown in FIGS. 6 (A) and 6 (B). This grommet 1 is a wire harness W / H
Small diameter portion 1a for penetrating and supporting the wire harness W
/ H is provided integrally with a large diameter portion 1b, and an annular engagement groove 4 for engaging a burring type through hole (burring hole) 3a provided in the wall portion 3 on the outer periphery of the large diameter portion 1a. Is provided. Further, the grommet 1 is provided with the lip portions 5 and 6, and the lip portions 5 and 6 are elastically pressed against the wall portion 3 to prevent water from entering from the outer side A to the inner side B. It is prevented.

[0004]

However, only by providing the two lip portions 5 and 6 as described above, for example, when a high-pressure jet flow is applied to the grommet 1 at the time of high-pressure car washing, the lip portions 5 and 6 are provided. There is a risk that water may leak from 6 and enter from the outer side A to the inner side B.

The grommet 1 has a lip portion 5
While pressing the wall part 3 from the inner side B, the wall part 7 facing the lip part 5 is fixed to the wall part 3 by pressing the wall part 3 from the outer side A. Therefore, the wire harness W / H
The wall portion 3 may be disengaged from the locking groove 4 when, for example, is bent at the tip of the small diameter portion 1a, and the mounting strength is not sufficient.

Further, in the above-mentioned grommet 1, since the tip 3c of the rising portion 3b of the burring hole 3a is in contact with the side wall 7, the edge of the tip 3c may damage the grommet 1.

Further, in FIG. 6, the burring hole 3 is formed.
The angle formed by the rising portion 3b of a and the wall portion 3 (burring angle θ) is 90 °. However, when the burring angle θ is different due to insufficient machining accuracy, the wall portion of the locking groove 4 is different. There is a problem that 3 cannot be fitted.

An object of the present invention is to solve the above-mentioned problems in the conventional grommet and to improve the waterproof property and the mounting strength to the wall portion. Another object of the present invention is to prevent damage due to the tip portion of the burring hole. Further, the present invention has been made for the purpose of enabling it to be attached to the wall portion even when the burring angle θ is different.

[0009]

Therefore, according to a first aspect of the present invention, an annular engaging groove that engages with an edge portion of a through hole provided in a wall portion and a first inserting hole that loosely inserts a wire harness are provided. A grommet having a diameter portion and a small diameter portion protruding from the large diameter portion provided with a second insertion hole communicating with the first insertion hole,
A first lip portion is provided on an outer end portion of the first side wall of the engaging groove, and an annular first concave portion is provided on the first side wall.
A second lip portion is formed between the recess and the bottom wall of the engagement groove, and a third lip portion is provided at the tip of the second side wall of the engagement groove.

According to a second aspect of the present invention, an annular second recess is provided on the first side wall at a distance from the first recess, and a fourth lip is provided between the first recess and the second recess. It may be configured.

According to a third aspect of the present invention, it is preferable that the tip of the third lip portion is located in the first recess and the first lip portion and the third lip portion overlap each other.

According to a fourth aspect of the present invention, it is preferable that an annular accommodation groove for accommodating the tip portion of the burring hole is provided in the connecting portion between the bottom wall and the second side wall.

It is preferable that the second side wall is inclined from the bottom wall toward the first side wall.

[0014]

In the grommet according to the first aspect, when the edge portion of the through hole is fitted into the locking groove, the first lip portion and the second lip portion are elastically pressed against one surface of the wall portion, and the wall portion The third lip portion is elastically pressed against the other surface of the.

When the fourth lip portion is provided as in claim 2, when the edge portion of the through hole is fitted into the locking groove, the first lip portion and the second lip portion are formed on one surface of the wall portion. The lip portion and the third lip portion are elastically pressed, and the third lip portion is elastically pressed against the other surface of the wall portion.

When the tip of the third lip portion is located in the first recess and the first lip portion and the third lip portion overlap each other, the first lip portion and the first lip portion Since the elastic force of the third lip portion to return to the original shape is large, the close contact between the first lip portion and the third lip portion and the wall portion is high, and the wall portion is the first lip portion and the first lip portion. It is firmly sandwiched by the 3 lip parts.

When the annular accommodating groove is provided as in the fourth aspect, the edge of the tip of the burring hole does not contact the grommet, and the grommet is not scratched or damaged such as cracks.

When the second side wall is inclined from the bottom wall toward the first side wall as in the fifth aspect, the grommets can be attached to the burring holes having various burring angles.

[0019]

Next, the present invention will be described in detail with reference to the embodiments shown in the drawings. The grommet 11 according to the first embodiment of the present invention shown in FIGS. 1 and 2 is made of an elastic material such as rubber or elastic resin, has a substantially conical outer shape, and has a wire harness W / H loosely inserted therein. It has a large diameter portion 13 provided with an insertion hole 13a and a small diameter portion 14 provided with a second insertion hole 14a that communicates with the first insertion hole 13a and inserts and holds the wire harness W / H.

The small-diameter portion 14 is provided with a bendable bellows-like portion 14b on the large-diameter portion 13 side and a wire harness stopping portion 14c on the tip end side. The wire harness stop portion 14c has an inner diameter smaller than the outer diameter of the wire harness W / H, and when the wire harness W / H is inserted into the grommet 11, the wire harness stop portion 14c has a wire It is designed to be in close contact with the outer periphery of the harness W / H. Also, the wire harness stopper 1
An annular rib 14d for tape fastening is provided at the tip of 4c, and the wire harness W / H can be fixed to the grommet 11 by winding the adhesive tape 15 around the wire harness fastening portion 14c and the outer circumference of the wire harness W / H. I am trying.

On the outer circumference of the large-diameter portion 13, an annular shape for engaging with an edge portion 17b of a burring type through hole (burring hole 17a) provided in a wall portion 17 formed of a vehicle body of an automobile or a panel of equipment. Is provided with a locking groove 18.

The locking groove 18 has a flat bottom wall 19 and first and second side walls 20 and 21 which are opposed to each other on both sides of the bottom wall 19.

The first side wall 20 on the side opposite to the small diameter portion 14 (on the side of the opening 13b of the large diameter portion 13) is substantially perpendicular to the bottom wall 19 (substantially parallel to the wall portion 17), An annular first lip portion 22 is provided at the outer end portion, and the first lip portion 22 projects toward the small diameter portion 14. This first
At the rising portion of the lip portion 22, the annular first recess 2
3 is provided, and a second lip portion 24 formed of a flat annular portion is formed between the first recess 23 and the bottom wall 19.

An annular accommodating groove 25 having a circular cross section is provided at the connecting portion between the second side wall 21 and the bottom wall 19 on the side opposite to the small diameter portion 14 (on the side of the opening 13b of the large diameter portion 13). The accommodation groove 25 accommodates the tip portion 17d of the burring hole 17a as described later.

The second side wall 21 is inclined from the connecting portion with the bottom wall 19 toward the first side wall 20,
In this embodiment, the angle α formed by the second side wall 21 and the bottom wall 19
Is 45 °. Further, the second side wall 21 has a taper shape that gradually narrows toward the tip side,
The tip portion constitutes the third lip portion 26. This third
The lip portion 26 is the first recess 23 provided in the first side wall 20.
It is located inside. The third lip portion 26 and the first side wall 2
The first lip portions 22 on the 0 side overlap each other by the lap margin R.

In the grommet of the first embodiment, the first lip portion 22, the third lip portion 26, and the second lip portion 24 are arranged in this order from the opening 18a side of the locking groove 18 toward the bottom wall 19 side. The lip is located. Further, a portion of the locking groove 18 surrounded by the second lip portion 24, the bottom wall 19 and the second side wall 21 forms an annular space 18c having a triangular cross section.

When the grommet 11 of the first embodiment having the above-mentioned structure is mounted in the burring hole 17a, it is possible to use the structure shown in FIG.
As shown by the middle arrow C, the small diameter portion 14 side is inserted into the burring hole 17a, and the edge portion 17b of the burring hole 17a is fitted into the locking groove 18. Edge 17 of burring hole 17a
When b is completely fitted into the locking groove 18, as shown in detail in FIG. 3, the surface 17e on the inner side B of the wall 17 has the first
The lip portion 22 and the second lip portion 24 are elastically pressed, while the third lip portion 26 is elastically pressed against the surface 17f on the outer side A of the wall portion 17. As described above, in the first embodiment, since the three lip portions from the first lip portion 22 to the third lip portion 26 are pressed against the wall portion 17, invasion of water from the burring hole 17a is reliably prevented. .

Further, in the grommet 11 of the first embodiment,
As described above, the edge portion 17b of the burring hole 17a is formed by the three lip portions from the first lip portion 22 to the third lip portion 26.
Since it is fixed to the wall by sandwiching it, the small diameter part 1
Even when a pulling force acts on the wire harness W / H as in the case where the wire harness W / H protruding from the tip of No. 4 is bent, the grommet 11 does not come off from the wall portion 17 and is sufficient. Mounting strength can be obtained.

In particular, since the first lip portion 22 and the third lip portion 26 are overlapped with each other by the lap margin R as described above, the grommet 11 is attached to the burring hole 17a and the tip of the first lip portion 22 is In the state where the wall portion 17 is sandwiched between the tips of the third lip portions 26, the first lip portion 22 and the third lip portion 26 are largely deformed in the directions away from each other, and are indicated by arrows X and Y in FIG. The elastic force of the first lip portion 22 and the third lip portion 26 to return to their original shapes is very large. Therefore, in the first embodiment, the first
The lip portion 22 and the third lip portion 26 and the wall portion 17 have a high degree of close contact with each other, so that the intrusion of water can be reliably prevented, and the first
Since the wall portion 17 is firmly sandwiched between the lip portion 22 and the third lip portion 26, the mounting strength is also high.

As shown in FIG. 3, the connecting portion between the wall portion 17 and the rising portion 17c of the burring hole 17a is located at the connecting portion between the second lip portion 24 and the bottom portion 19, and the tip portion 17d of the rising portion 17c is It is located in the accommodation groove 25. Therefore, the tip portion 17d of the rising portion 17c
Is not in contact with the grommet 11, the edge of the tip portion 17d does not damage the grommet 11 and damage such as cracks can be prevented, and the grommet 11 can be prevented from deteriorating from the damaged portion.

Further, in the first embodiment, as described above, the second
The side wall 21 is inclined toward the first side wall 20, and the locking groove 18
Since the annular space 18c having a triangular cross-section is provided at, even when the burring angle θ of the burring hole 17a becomes an acute angle of 90 ° or more, as shown by the alternate long and short dash line in FIG.
The wall portion 17 has three portions, from the first lip portion 22 to the third lip portion 26.
The two lip portions are elastically pressed, and the tip portion 17d of the rising portion 17c is located in the accommodation groove 25. As described above, in the first embodiment, the grommet 11 can be attached to the burring hole 17a even when the burring angle θ is different. In the first embodiment, the second side wall 2
Since the angle α formed by 1 and the bottom wall 19 is 45 °,
If the burring angle θ is in the range of 90 ° to 45 °, the grommet 11 can be attached to the burring hole 17a.

FIG. 4 shows a grommet 11 'according to the second embodiment of the present invention. In the grommet 11 ′ according to the second embodiment, an annular second recess 2 parallel to the first recess 23 is provided between the first recess 23 of the first wall 17 and the bottom wall 19.
7 is provided, and the fourth lip portion 28 is formed between the first recess 23 and the second recess 27. The other structure of the second embodiment is the same as that of the first embodiment.

As shown in FIG. 5, when the grommet 11 'of the fourth embodiment is attached to the burring hole 17a, the first lip portion 22 and the second lip portion are formed on the surface 17e on the inner side B of the wall portion 17. While the 24 and the fourth lip 28 are elastically pressed, the outer side A surface 17f of the wall 17 is elastically pressed by the third lip, so that a total of four lip parts are pressed by the wall 17. Pressed. Therefore, infiltration of water from the burring hole 17a is reliably prevented, and sufficient mounting strength is obtained.

Since the first lip portion 22 and the third lip portion 26 are overlapped with each other by the lap margin R as described above, the adhesion between the wall portion 17 and the first lip portion 22 and the third lip portion 26 is high. The penetration of water is highly prevented, and since the wall portion 17 is firmly sandwiched between the first lip portion 22 and the third lip portion 26, the attachment strength is also high.

Further, since the leading end 17d of the rising portion 17c of the burring hole 17a is located in the accommodation groove 25 and does not contact the grommet 11 ', the edge of the leading end 17d damages the grommet 11' and this damage causes the grommet 11 '. It is possible to prevent 11 'from being deteriorated.

Further, as in the first embodiment, the second side wall 21 is inclined toward the first side wall 20 to provide the engaging groove 18 with the annular space 18c having a triangular cross section, so that FIG.
As shown by the alternate long and short dash line, the grommet 11 ′ can be attached to the burring hole 17a even when the burring angle θ of the burring hole 17a becomes an acute angle of 90 ° or less.

The present invention is not limited to the above embodiment, and various modifications can be made. For example, although the accommodation groove 25 has a circular cross-sectional shape in the above embodiment, the accommodation groove 25 is not limited to a circular cross-sectional shape, and the tip portion of the burring hole 17a may have a polygonal shape such as a triangle, a quadrangle, or an ellipse. Any shape may be used as long as 17d can be inserted. Further, in the above embodiment, the opening 13b side of the large diameter portion 13 of the locking groove 18 is the first side wall 20 and the small diameter portion 14 side is the second side wall, but the first side wall 20 is the small diameter portion 14 side and the second side wall. The side wall 21 may be provided on the opening 13b side. Furthermore, the shape of the small-diameter portion 14 is not limited to the one shown in FIG. Although the grommets 11 and 11 'are attached to the burring holes 17a in FIGS. 3 and 5, the grommet 1
It is also possible to attach 1, 11 'to a normal through hole without the rising portion 17c.

[0038]

As is apparent from the above description, in the grommet according to the first aspect, the first lip portion of the first side wall of the engaging groove is provided, and the first concave portion is provided so that the first concave portion and the engaging groove are provided. A second lip portion is formed between the bottom walls of the above, and a third lip portion is provided at the tip of the second side wall of the engaging groove. Therefore, claim 1
In the grommet, when the edge portion of the through hole is fitted into the locking groove, the first lip portion and the second lip portion are elastically pressed against the one surface of the wall portion and the other surface of the wall portion. Causes the third lip portion to be elastically pressed. Thus, in the grommet according to the first aspect, since the three lip portions press the wall portion, it is possible to reliably prevent the intrusion of water from the through hole, and
It can be firmly attached to the wall.

According to a second aspect, the first side wall is provided with the first
When the annular second concave portion is provided with a space from the concave portion and the fourth lip portion is provided between the first concave portion and the second concave portion, four lip portions from the first lip portion to the fourth lip portion are provided. Since the wall portion is pressed against the wall portion, it is possible to reliably prevent the intrusion of water through the through hole and firmly attach the wall portion to the wall portion.

When the tip of the third lip portion is located in the first recess and the first lip portion and the third lip portion overlap each other, the first lip portion and the first lip portion The elastic force of the second lip portion to return to the original shape is very large, the degree of adhesion between the first lip portion and the third lip portion and the wall portion is high, and it is possible to reliably prevent the infiltration of water. At the same time, since the wall portion is firmly sandwiched between the first lip portion and the second lip portion, the attachment strength to the wall portion can be further improved.

When an annular accommodation groove for accommodating the tip portion of the burring hole is provided in the connecting portion of the bottom wall and the second side wall as in claim 4, the edge of the tip portion scratches the grommet, It is possible to prevent the grommet from deteriorating from the damaged portion without causing damage such as cracks.

When the second side wall is inclined from the bottom wall toward the first side wall as in the fifth aspect, the grommet can be attached to the burring holes having various burring angles.

[Brief description of drawings]

FIG. 1 is a sectional view showing a grommet according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view showing a portion II of FIG.

FIG. 3 is an enlarged sectional view of an essential part showing a state in which the grommet of the first embodiment is attached to a wall part.

FIG. 4 is an enlarged view of a main part showing a grommet according to a second embodiment of the present invention.

FIG. 5 is an enlarged sectional view of an essential part showing a state in which the grommet according to the second embodiment is attached to the wall part.

6A is a cross-sectional view showing an example of a conventional grommet, and FIG. 6B is an enlarged view of a main part of FIG.

[Explanation of symbols]

 11, 11 'Grommet 13 Large diameter portion 13a First insertion hole 14 Small diameter portion 14a Second insertion hole 19 Bottom wall 20 First side wall 21 Second side wall 22 First lip portion 23 First recess 24 Second lip portion 25 Storage groove 26 3rd lip part 27 2nd recessed part 28 4th lip part

Claims (5)

[Claims] 1. A large-diameter portion provided with an annular engagement groove that engages with an edge portion of a through hole formed in a wall portion and a first insertion hole for loosely inserting a wire harness, and communicates with the first insertion hole. A small diameter portion protruding from the large diameter portion provided with a second insertion hole for providing a first lip portion at the outer end portion of the first side wall of the engaging groove, and An annular first recess is provided on the side wall to provide the first
A grommet characterized in that a second lip portion is formed between the recess and the bottom wall of the engagement groove, and a third lip portion is provided at the tip of the second side wall of the engagement groove. 2. The first side wall is provided with an annular second recess spaced apart from the first recess, and a fourth lip is provided between the first recess and the second recess. Claim 1
Grommet described in. 3. The grommet according to claim 1, wherein the tip of the third lip portion is located in the first recess, and the first lip portion and the third lip portion overlap each other. . 4. The ring-shaped accommodating groove for accommodating the tip end portion of the burring hole is provided in the connecting portion between the bottom wall and the second side wall, according to any one of claims 1 to 3. The grommet according to item 1. 5. The second side wall extends from the bottom wall to the first side wall.
The grommet according to any one of claims 1 to 4, wherein the grommet is inclined toward the side wall.