JPH08329758A - Crommet for gas seal - Google Patents

Abstract

PURPOSE: To provide a grommet for a gas seal which is installed in a partition wall inserting part of a wire harness. CONSTITUTION: A grommet performs a gas seal by being installed in a wire harness penetrating through an opening of a partition wall. The grommet 12 is a solid body composed of an elastic material such as rubber or elastomer, and an external shape of the solid body is formed in the shape being brought into close contact with an inner peripheral surface of the opening, and plural electric wire inserting holes 15 to insert electric wires 13 of an electric wire group constituting the wire harness one by one in a close contact condition, are penetratingly bored so as to open in both end surfaces of the solid body. A projecting part and a recessed part are continuously arranged on inner peripheral surfaces of the respective electric wire inserting holes 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grommet for a gas seal used in an electric vehicle, and more specifically, it penetrates a partition wall so that hydrogen gas generated during charging of a battery does not enter a required area separated by the partition wall. The present invention relates to a grommet attached to a wire harness.

[0002]

2. Description of the Related Art Recently, various electric vehicles have been provided, and hydrogen gas is generated in the electric vehicles when charging a battery. If the hydrogen gas enters a box containing a control device such as a sensor, a spark may be generated in the box, and the invaded hydrogen may be ignited. Therefore, it is necessary to reliably prevent gas from entering through the insertion portion of the wire harness connected to the control device in the box.

Conventionally, when inserting a wire harness through an opening provided in a vehicle body panel or the like, various waterproof and dustproof grommets have been proposed for sealing the opening. This type of grommet has the most general shape shown in FIGS. 10 (A) and (B), is made of rubber or elastomer, and grommets a wire harness W / H in which a large number of electric wires w are bound by tape winding or the like. The electric wire insertion portion 1a composed of the small diameter cylindrical portion 1 is expanded and inserted, and the electric wire insertion portion 1
The engaging groove 1c provided on the outer peripheral surface of the enlarged diameter portion 1b continuous with a is engaged with the peripheral edge of the through hole 2 of the vehicle body panel P, and the lip 1d provided in the vicinity of the engaging groove 1c is pressed against the vehicle body panel P. And attached.

The grommet presses the inner peripheral surface of the wire insertion portion 1a against the outer peripheral surface of the wire harness W / H to seal between the wire harness W / H and the grommet 1, and
The gap between the grommet 1 and the through hole 2 is sealed by a lip 1d to prevent water from entering from the outside X of the vehicle body into the inside Y of the vehicle body, and also to prevent dust.

[0005]

The conventional grommet shown in FIG. 10 functions sufficiently for waterproofing and dustproofing, but is insufficient for gas sealing. That is, since a large number of electric wires are wrapped with a tape and bound to form a wire harness and are passed through a grommet, gaps are unavoidably generated between the bound electric wires, and these gaps are sealed. Not not. To seal the gaps between the electric wires, a sealant is also filled, but it is very difficult for the sealant to penetrate into all the gaps between the electric wires to completely seal the electric wires. .

Therefore, the grommet shown in FIG. 10 conventionally provided for waterproofing and dustproofing is insufficient in terms of sealing property to be used as a grommet for a gas seal in an electric vehicle. There is a demand for the development of a grommet that can reliably shut off the power.

The present invention meets the above-mentioned demands, and an object of the present invention is to provide a grommet for a gas seal, which can surely block the flow of gas and facilitate wiring work.

[0008]

To achieve the above object, the present invention provides a grommet according to claim 1, which is attached to a wire harness penetrating an opening of a partition wall to perform gas sealing, wherein the grommet is rubber or A plurality of solid bodies made of an elastic material such as an elastomer, the outer shape of the solid body being in a shape of closely adhering to the inner peripheral surface of the opening, and a plurality of electric wires of an electric wire group forming a wire harness being inserted in close contact with each other. There is provided a grommet for a gas seal, characterized in that the electric wire insertion hole is opened at both end surfaces of the solid body so as to penetrate therethrough.

According to a second aspect of the present invention, there is provided a grommet in which an uneven portion is continuously provided on the inner peripheral surface of the wire insertion hole from the wire insertion side to the wire drawing side. According to the third aspect, the grommet is provided in which the inclination of each convex portion of the concave-convex portion is set such that the inclination angle on the wire insertion side is smaller than the inclination angle on the wire extraction side.

According to a fourth aspect of the present invention, when an uneven portion is provided in the wire insertion hole, the diameter of the hollow portion surrounded by the protruding end of the convex portion is
(EN) Provided is a grommet in which the diameter of a wire to be inserted is set to be equal to or smaller than the diameter of a terminal connected to a tip of an electric wire to be inserted, and the diameter of a hollow portion surrounded by a bottom end of a recess is set.

According to a fifth aspect of the present invention, one electric wire insertion hole is formed along the central axis, and the electric wire insertion holes are formed at concentric intervals in the radial direction at intervals in the circumferential direction. There is provided a grommet in which an annular groove is provided on the end surface on the electric wire insertion side between the electric wire insertion holes formed at intervals.

According to a sixth aspect of the present invention, the grommet is attached to a wire harness installed in a box for accommodating a control device installed near a battery in an electric vehicle, and the partition wall is an outer wall of the box. The opening provided in is formed by a cylindrical portion projecting from the outer wall, and the grommet is a cylindrical solid body that is inserted into the cylindrical portion, and an annular rib that closely adheres to the inner peripheral surface of the cylindrical portion is provided on the outer periphery thereof. In addition, a locking groove for locking the locking projection protruding from the inner peripheral surface of the cylindrical portion is provided, and the insertion side into the cylindrical portion is formed by gradually reducing the diameter, and the wire insertion of the grommet is performed. The gas seal according to any one of claims 1 to 5, wherein a gas is prevented from entering from the outside of the box to the inside of the box by arranging an electric wire through the hole. It provides a grommet.

[0013]

In the grommet according to the first aspect of the invention, the electric wires are divided one by one and passed through the electric wire insertion holes of the grommet, and the electric wires are sealed in the respective electric wire insertion holes. It is possible to eliminate the gap between the electric wires that occurs when the wires are inserted into the. In this way, the gap generated between the electric wires can be completely eliminated, so that the flow of gas can be reliably cut off.

Further, in the grommet according to claims 2 and 4, since the inner diameter of the hollow portion surrounded by the tips of the protrusions of the uneven portion of the wire insertion hole is set to be equal to or less than the outer diameter of the wire, the wire The tip of the convex portion comes into pressure contact with the outer periphery of and can be reliably sealed. On the other hand, since the inner diameter of the hollow portion surrounded by the bottom end of the recess is larger than the width of the terminal fitting to which the electric wire is connected, the terminal fitting can be easily inserted into the electric wire insertion hole. In addition, since the seal portion formed by the convex portion is provided at a plurality of places with the concave portion separated, the sealability can be further improved.

Further, as described in claim 3, when the inclination of the protruding portion on the wire insertion side is formed gently, the inclination of the protruding portion is gentle on the insertion side when the terminal metal fitting is inserted, so that the protruding portion is inserted at the time of insertion. The narrowest range of the tip of the convex part is a small range as it passes while pressing and widening, so that it is possible to easily get over the narrow range and perform the wire passing work more smoothly.

If a groove is provided on the end face of the grommet on the wire insertion side as described in claim 5, the wire insertion hole can easily follow in the direction in which the inserted wire is pulled. It is possible to secure the sealing property between the holes. That is, when the electric wire that is passed through the grommet is loaded from the vertical and horizontal directions, or when the electric wire is pulled by bending it in the vertical and horizontal directions, and the wire is pulled,
The wire insertion hole through which the wire is inserted is enlarged, and the sealing property with the wire is impaired. On the other hand, if an annular groove is provided, the groove will be crushed no matter which direction the wire is pulled, and the wire insertion hole will be extended in the wire pulling direction without expanding the wire insertion hole. Can be followed.

When the annular rib is provided on the outer peripheral portion of the grommet as described in claim 6, the grommet is reliably sealed with respect to the opening of the box. Therefore, it is possible to prevent gas from entering the inside of the box from the outside of the box. Further, when the grommet can be fixed to the box by the locking groove and the insertion side into the opening is reduced in diameter, the grommet can be easily inserted into and attached to the opening.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to an embodiment including a grommet attached to a wire harness insertion portion of a control device housing box installed near a battery of an electric vehicle. In FIG. 1, reference numeral 10 denotes a box accommodating a control device (not shown) such as a sensor, which is arranged inside a large battery box (not shown) accommodating a battery. Reference numeral 11 denotes a cylindrical portion having an opening 11a at the tip protrudingly provided on the outer wall of the box 10 serving as a partition wall, 12 a grommet fitted into the cylindrical portion 11, and 13 a grommet 12
Is a plurality of electric wires that form a wire harness W / H that is inserted into the wire harness.

The grommet 12 is formed of rubber or elastomer as a substantially cylindrical solid body, and has an electric wire insertion hole 15 for inserting the plurality of electric wires 13 one by one.
Are formed so as to penetrate in the front-rear direction from the front end face 12a to the rear end face 12b, and the electric wire insertion holes 15 are provided at required intervals.

As shown in the enlarged view of FIG. 2B, each wire insertion hole 15 has a rear end surface 1 from the wire insertion side on the front end surface 12a side.
A convex portion 16 and a concave portion 17 are continuously formed toward the wire drawing side on the 2b side, and the peripheral edges of the inlet 15a and the outlet 15b are rounded and have a diameter increased.

The convex portion 16 and the concave portion 17 are each formed in an annular shape on the inner peripheral surface, and the inner diameter r1 of the hollow portion surrounded by the projecting end 16a of the convex portion 16 is set to be equal to or less than the outer diameter of the electric wire 13 to be inserted. In addition, the inner diameter r2 of the hollow portion surrounded by the bottom end 17a of the recess 17 is set to be slightly larger than the width of the terminal fitting 14 connecting to the electric wire 13.

On the outer peripheral surface of the grommet 12, three annular ribs 18 are provided at intervals in the axial direction, and an annular engaging groove 19 is provided behind the ribs 18. Further, the diameter of the rear portion 12c of the locking groove 19 is gradually reduced.

The outer diameter of the annular rib 18 is set to be slightly larger than the inner diameter of the box cylindrical portion 11 so that the annular rib 18 is pressed and brought into pressure contact with the inner peripheral surface of the cylindrical portion 11. . Further, a locking projection 20 is provided so as to project from the inner peripheral surface of the cylindrical portion 11, and the locking groove 1 of the grommet 12 is provided.
It fits inside 9.

The grommet 12 is shown in FIG.
As shown in (B), the wire 13 having the terminal metal fitting 14 crimped to the tip in advance is inserted into each wire insertion hole 15 from the inlet 15a and pulled out from the outlet 15b to be attached. The electric wire 13 can be easily inserted into the electric wire insertion hole 15 because the inlet 15a is enlarged.
Since the concave portions 17 through which the terminal fittings 14 can be smoothly passed are alternately provided with the convex portions 16 inside, the convex portions 1
It is possible to easily pass the electric wire 13 while pushing out the wire 6.

Further, the electric wire 1 inserted through the electric wire insertion hole 15
3, the tip end portions 16a of the convex portions 16 are pressed against each other at a plurality of positions for sealing, and the gaps between the electric wires 13 and the electric wire insertion holes 15 are completely eliminated.

As shown in FIG. 3B, the electric wire 13 is attached to the grommet 12, and the electric wire 13 is attached to the box 10. At that time, first, the grommet 1 of the electric wire 13
The part of 2 which is pulled back is inserted through the cylindrical part 11. Then, the reduced diameter rear portion 12 c of the grommet 12 is inserted into the cylindrical portion 11. Since the outer periphery of the rear portion 12c is smaller than the inner diameter of the cylindrical portion 11, it can be easily inserted.

When the grommet 12 is pushed into the cylindrical portion 11, the engaging projection 2 of the cylindrical portion 11 is inserted into the engaging groove 19 on the outer periphery thereof.
0 is inserted and positioned and fixed, and the annular rib 18
Is pressed against the inner peripheral surface of the cylindrical portion 11.
Therefore, there is surely no gap between the outer peripheral surface of the grommet 12 and the inner peripheral surface of the cylindrical portion 11 of the box 10.

As described above, since the electric wire 13 and the grommet 12 are completely sealed and the grommet 12 and the cylindrical portion 11 of the box 10 are completely sealed, hydrogen gas generated when the battery is charged enters the box 10. Can be prevented.

FIGS. 4 and 5A and 5B show a second embodiment, in which a plurality of electric wire insertion holes 15 provided in the grommet 12 are provided.
The shape of the concavo-convex portion formed on the inner peripheral surface of is different from that of the first embodiment.

That is, the convex portion 16 is projected in a mountain shape, and the inclination angle of the inclined surface 16a on the wire insertion side is a gentle inclination angle of about 30 degrees, while the inclination angle of the inclined surface 16b on the wire extraction side is opposite. The inclination angle is a steep inclination angle of about 80 degrees so that the electric wire 13 can be easily inserted from the insertion side.

In the grommet of the second embodiment, when the electric wire 13 is inserted into the electric wire insertion hole 15, the inclination of the electric wire insertion side inclined surface 16a of the convex portion 16 protruding into the hollow portion of the electric wire insertion hole is gentle. It is carried out while pushing out with the terminal fitting 14 at the tip. Moreover, the tip 16 of the convex portion 16 that becomes the narrowest
Since the distance between a is small, it can be easily overcome and proceed. Thus, the work of passing the electric wire 13 through the electric wire insertion hole 15 can be performed more smoothly.

FIG. 6 shows the grommet of the third embodiment, in which the inner peripheral surface of the wire insertion hole 15 of the grommet is not provided with a concavo-convex portion, and the inner diameter of the grommet is closely contacted with the outer peripheral surface of the electric wire 13 to be inserted. Is set to.

The electric wire insertion hole of the third embodiment is more difficult to pass the electric wire than the electric wire insertion hole of the first and second embodiments.
The terminal fitting 14 connected to the tip of the wire 3 allows the electric wire insertion hole to be pushed and spread. Especially grommet 12
It can be preferably used when the total length of the wire insertion hole 15 from the wire insertion end to the wire pull-out end is short.

7 to 9 show the grommet of the fourth embodiment. In the grommet 12 of the fourth embodiment, a plurality of electric wire insertion holes 15 are formed along the central axis line, and are also formed at regular intervals in the circumferential direction on the concentric circles with the required intervals in the radial direction. I have set up.

Further, on the front end face 12a of the grommet 12, between the central electric wire insertion hole 15-I and the electric wire insertion hole 15-II located on the outer periphery thereof, a circular ring-shaped inner peripheral side groove 3 having a small diameter is formed.
0 is recessed, and a large-diameter outer peripheral groove 31 is recessed on the outer periphery of the outer peripheral wire insertion hole 15-II. In this embodiment,
The width of the grooves 30 and 31 is about 1 mm, and the depth is about 1.5 mm.

As described above, the wire insertion holes 15-I, 15-I
When the grooves 30 and 31 are provided in the vicinity of I, as shown in FIG. 9, when external stress is applied to the electric wire 13 in the vertical and horizontal directions, or when the electric wire 13 is bent by bending in the vertical and horizontal directions and wired, 30 and 31 are crushed, and the wire insertion hole 15-
I, 15-II can be made to follow the bending direction of the electric wire 13. Therefore, the wire 13 and the wire insertion holes 15-I, 15
It is possible to maintain the sealing property without generating a gap with -II.

The grommet has a high rigidity, and
When the electric wire insertion hole does not easily follow the electric wire because the grooves 30 and 31 are not provided, when the electric wire 13 is pulled vertically and horizontally, the electric wire insertion hole is formed in the pulling direction of the electric wire 13. The diameter is increased, and a gap is likely to be formed between the electric wire 13. On the other hand, as in the fourth embodiment, the grooves 30, 3
1 is provided and the grooves 30 and 31 are formed in an annular shape, no matter which direction the electric wire 13 is pulled, the groove 3
It is possible to crush 0 and 31 and make the wire insertion hole follow the direction in which the wire is pulled.

[0038]

As is apparent from the above description, in the grommet for gas seal according to claim 1 of the present invention, unlike the conventional one, the electric wires are divided into individual wires and passed through the electric wire insertion holes of the grommet, respectively. Since the electric wires are respectively sealed by the electric wire insertion holes, it is possible to surely eliminate a gap between the electric wires which is generated when the conventional electric wires are bound and inserted into the grommet.
Therefore, the gas flow can be blocked and the gas can be sealed.

Further, in the grommet according to claims 2 and 4, since the uneven portion is provided on the inner peripheral surface of the wire insertion hole, the protruding portion can be pressed against the outer circumference of the wire to achieve sealing at a plurality of points. Moreover, since the concave portions and the convex portions are provided alternately,
Wire insertion work can be facilitated.

In particular, when the slope of the convex portion on the electric wire insertion side is formed gently as in the third aspect, the electric wire can be passed through the electric wire insertion hole more smoothly, which facilitates the wire passing operation.
Work efficiency can be improved.

When a groove is provided on the end surface on the wire insertion side as in the grommet according to claim 5, when the wire is subjected to a pulling force in the vertical and horizontal directions, the groove is crushed and the wire insertion hole is formed in the wire. It can be made to follow, and a sealing property can be maintained without creating a gap between the electric wire and the electric wire insertion hole.

Further, in the grommet according to the sixth aspect, since the annular rib is provided on the outer peripheral portion, the grommet and the box opening can be reliably sealed. further,
By fitting the locking groove of the grommet and the locking projection on the box side, positioning and fixing of the grommet can be done easily and securely. Furthermore, since the diameter of the insertion side of the grommet is reduced, the work of inserting and mounting the grommet box into the cylindrical portion can be easily performed.

[Brief description of drawings]

FIG. 1A is a perspective view showing a state in which a grommet according to a first embodiment of the present invention is attached to a box, and FIG. 1B is a sectional view.

2A is a perspective view of the grommet of FIG. 1, and FIG.
Is a sectional view.

FIG. 3A is a perspective view before inserting the electric wire into the grommet, and FIG. 3B is a perspective view after inserting the electric wire into the grommet.

FIG. 4 is a sectional view showing a state in which the grommet of the second embodiment of the present invention is attached to the box.

FIG. 5A is a sectional view of the grommet of the second embodiment,
(B) is a partially enlarged view of (A).

FIG. 6 is a sectional view of a grommet according to a third embodiment of the present invention.

FIG. 7 is a perspective view showing a state in which an electric wire is attached to the grommet of the fourth embodiment of the present invention.

FIG. 8 is a side view of the grommet of the fourth embodiment.

FIG. 9 is a perspective view showing the action of the grommet of the fourth embodiment.

FIG. 10A is a sectional view showing a conventional grommet,
(B) is a BB line sectional view of (A).

[Explanation of symbols]

 10 box 11 cylindrical part 11a opening 12 grommet 13 electric wire 14 terminal fitting 15 electric wire insertion hole 16 convex part 17 concave part 18 annular rib 19 locking groove 20 locking projection 30, 31 groove

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiromitsu Sato 4630 Shimotakanezawa, Haga-cho, Haga-gun, Tochigi Prefecture Inside the Honda R & D Co., Ltd. (72) Satoshi Watanabe 4630 Shimotakanezawa, Haga-cho, Haga-gun, Tochigi (72) Inventor Yuichi Nakamura 4630 Shimotakanezawa, Haga-cho, Haga-gun, Tochigi Prefecture

Claims (6)

[Claims] 1. A grommet which is attached to a wire harness penetrating an opening of a partition wall to perform gas sealing, wherein the grommet is a solid body made of an elastic material such as rubber or elastomer, and the outer shape of the solid body is within the opening. A plurality of wire insertion holes are formed on both ends of the solid body so as to be in close contact with the peripheral surface, and the wires of the wire group forming the wire harness are inserted in close contact with each other. Grommet for gas seals, which is characterized by 2. The grommet according to claim 1, wherein a concavo-convex portion is continuously provided on the inner peripheral surface of the wire insertion hole from the wire insertion side to the wire drawing side. 3. The grommet according to claim 2, wherein an inclination angle of each convex portion of the concave-convex portion is set such that an inclination angle on the wire insertion side is smaller than an inclination angle on the wire extraction side. . 4. The diameter of the hollow portion surrounded by the protruding end of the convex portion of the electric wire insertion hole is set to be equal to or smaller than the diameter of the electric wire to be inserted, and the diameter of the hollow portion surrounded by the bottom end of the concave portion. To
The grommet according to claim 2 or 3, wherein the width is set to be equal to or larger than the width of the terminal connected to the tip of the electric wire to be inserted. 5. The wire insertion hole is formed along the central axis line.
And the concentric holes that are spaced apart in the radial direction, are spaced apart in the circumferential direction, and the wire insertion holes on the wire insertion side are located between the wire insertion holes that are spaced apart in the radial direction. The grommet according to any one of claims 1 to 4, wherein an annular groove is provided on the end surface. 6. The grommet is attached to a wire harness arranged in a box for accommodating a control device installed near a battery in an electric vehicle, wherein the partition wall is an outer wall of the box, and an opening provided in the outer wall of the box is Formed by a cylindrical portion protruding from the outer wall, the grommet is a cylindrical solid body to be inserted into the cylindrical portion, the outer periphery of which is provided with an annular rib closely contacting the inner peripheral surface of the cylindrical portion, and a cylinder An engaging groove for engaging with an engaging projection protruding from the inner peripheral surface of the part is formed, and the insertion side into the cylindrical part is formed by gradually reducing the diameter, and the wire is distributed through the wire insertion hole of the grommet. The grommet according to any one of claims 1 to 5, wherein the grommet is configured to prevent gas from entering from the outside of the box into the inside of the box.