JPH10224959A - Waterproof structure for wire harness in automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance waterproof performance at the part for fixing a grommet in an automobile. SOLUTION: In a waterproof structure where a wire harness W/H is inserted through a grommet 10 comprising an enlarged part and a small diameter tubular part into a through hole made through a panel partitioning the outdoor side and the indoor side of an automobile and the grommet 10 is filled with a water stopping agent, the enlarged part of the with harness W/H is arranged at a part where a sheet-like water absorbing material 15 is wound spirally between wires (w) and bundled. Furthermore, a part 15a of the water absorbing material 15 is brought into contact with a water stopping layer 14 filling the enlarged part 11 while the other part 15b is projected outward from the water stopping layer 14 and exposed to the outer air so that the water absorbing material is not saturated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof structure for a wire harness for an automobile, and more particularly, to a through-hole provided in a panel that separates the interior and exterior of an automobile engine room or the like into a through-hole. In a waterproof structure in which a wire harness is inserted through a grommet made of and a waterproofing agent is filled in the grommet, it is possible to reliably prevent water from entering the room through gaps between wires of the wire harness. It is.

[0002]

2. Description of the Related Art In an automobile, as shown in FIG. 9, a panel 1 for separating the engine room from the vehicle compartment is provided to prevent water from penetrating from a through portion of a wire harness routed from the engine room side to the vehicle compartment. A grommet 2 made of rubber or an elastomer is attached to the wire harness W / H that penetrates the provided through hole 1a, and the wire harness W / H is wired through the grommet 2 to prevent water from flowing through the through hole 1a. I have.

The grommet 2 has a shape in which a small-diameter tube portion 2b is continuous with a reduced end of a large-diameter portion 2a having a substantially conical cylindrical shape, and a panel locking portion 2c provided on the outer peripheral surface of the large-diameter portion 2a is provided with a panel locking portion 2c.
The wire harness W / H is inserted into the small-diameter pipe portion 2b protruding toward the engine room side in close contact with the inner peripheral edge of the through hole 1a. Furthermore, in order to ensure waterproofness, a water blocking agent is filled into the enlarged diameter portion of the grommet 2 to seal between the electric wires w of the wire harness W / H and between these electric wires and the inner peripheral surface of the grommet to achieve waterproofing. ing.

Further, in Japanese Utility Model Laid-Open No. 63-37027, as shown in FIG. 10, a swelling agent 3 is filled between wires of a wire harness W / H inserted into a grommet 1.
A structure has been proposed in which water that penetrates through gaps between electric wire groups is absorbed.

[0005]

However, if the water-blocking agent in the grommet deteriorates due to aging, a gap formed between the wires of the wire harness and a gap formed between the water-blocking agent and the outer peripheral surface of the wire harness. There is a risk of flooding through Also, when a swelling agent is filled as described in Japanese Utility Model Application Laid-Open No. 63-37027, there is a problem that the water stopping effect is lost when the water absorbed by the swelling agent becomes saturated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and the water-stopping agent filled in the grommet is deteriorated, so that the space between the electric wires of the wire harness and between the water-stopping agent and the outer peripheral surface of the wire harness is reduced. An object of the present invention is to surely prevent infiltration through a gap when a gap is formed in the gap.

[0007]

In order to solve the above-mentioned problems, the present invention is directed to a first aspect of the present invention, wherein a through-hole provided in a panel that separates the outside and the inside of a vehicle from a large-diameter portion and a small-diameter cylindrical portion is provided. In a waterproof structure in which a wire harness is inserted through a grommet, and a waterproofing agent is filled in the grommet,
A portion arranged in the enlarged diameter portion of the wire harness,
While a water absorbing material is interposed between the bundled electric wires, a part of the water absorbing material is brought into contact with the water blocking agent layer filled in the enlarged diameter portion, and the other portion is connected to the water stopping agent layer. The waterproof structure of a wire harness for an automobile is characterized in that the waterproof structure is exposed to the outside air by projecting from outside to prevent the water absorbing material from being saturated with water.

With the above construction, the water-stopping agent filled in the grommet deteriorates, and a gap is formed between the wires of the wire harness electric wire group, and further, between the water-stopping agent and the outer peripheral surface of the wire harness. Even if water is generated, water can be absorbed by the water-absorbing material and water can be prevented from entering the room. Further, since a part of the water-absorbing material is exposed to the outside air, the absorbed water can be evaporated, and the water-absorbing material does not become saturated. Therefore,
Water can be reliably prevented from entering the room through the gap in the grommet.

The above-mentioned water-absorbing material is a long flexible sheet-like material in which water-absorbing particles such as a water-absorbing polymer and silica gel are housed in a water-permeable and air-permeable fiber bag. Preferably, the long flexible sheet is wound in a spiral shape, and an electric wire is arranged between the facing sheet surfaces of the wound (claim 2). In addition, the water-absorbing material includes a plurality of short flexible sheet-like articles each containing a water-absorbing polymer, water-absorbing granules such as silica gel in a fiber bag having water permeability and air permeability, One end of each of the plurality of short flexible sheet-like objects is collectively fastened to one, and the other end of each sheet-like material is radially spread around the fastening portion and arranged. In addition, it is preferable that an electric wire is arranged between adjacent ones of the plurality of flexible sheets arranged radially (claim 3). In addition, it is not limited to what has flexibility, but may have rigidity.

With this configuration, the contact area between the water-absorbing material and the electric wire in the entire wire harness can be increased, and the water entering through the gap between the electric wires can be efficiently absorbed by the water-absorbing material. In addition, a water-absorbing material can be easily interposed between the electric wires of the wire harness, and the work of creating a wire harness that converges the water-absorbing material together with the electric wires can be easily performed.

Preferably, the bags are divided into small bags and are continuous in the length direction. As described above, when the sachets are divided, the internal particle distribution can be made uniform. In addition, since the sheet-like material can be easily bent, the work of creating a wire harness that bundles the electric wire and the water-absorbing material can be easily performed.

[0012] It is preferable that the grommet has a two-stage enlarged diameter portion having a middle diameter portion and a large diameter portion, and the water absorbing material is disposed along a straight inner peripheral surface of the middle diameter portion.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

1 to 5 show a first embodiment. The shape of the grommet 10 molded from rubber or elastomer is composed of an enlarged-diameter portion 11 and a small-diameter tube portion 12 connected to the reduced end side of the enlarged-diameter portion 11, and the small-diameter tube portion 12 forms a wire harness W / H. The wire group to be inserted is inserted in a state of being in close contact with the inner peripheral surface thereof. The enlarged diameter portion 11 is opened in a conical shape from the small diameter tube portion 11 to have a straight pipe shape, and the large diameter portion 11 is opened in a conical shape from the middle diameter portion 11-1 to have a straight pipe shape. -2, and a vehicle body engaging groove 13 is recessed in the outer peripheral surface of the large diameter portion.

The wire harness W / H (wire group) passing through the small-diameter cylindrical portion 12 passes through the center of the large-diameter portion 11 and passes through the grommet 10. A water-stopping agent is filled in the enlarged diameter portion 11, and a water-stopping agent layer is provided between the electric wire groups of the wire harness W / H and from the outer periphery of the electric wire group to the inner peripheral surface side of the middle diameter portion 11-1 of the enlarged diameter portion 11. 14 are provided.

Further, a portion of the wire harness W / H which is disposed from the middle diameter portion 11-1 to the large diameter portion 11-2 of the grommet 10 is provided with a plurality of electric wires w and a flexible sheet-like water absorbing material. The material 15 is converged to form a structure in which electric wires are arranged between opposed sheet surfaces of the sheet-shaped water-absorbing material 15 wound in a spiral shape. A part 15a is located at a position where the inner peripheral surface of the waterproofing agent layer 14 is in contact with the waterproofing agent filled between the electric wires w of the wire harness W / H, and the other portion 15b is a surface 14a of the waterproofing agent layer 14. The position is made to protrude further and is exposed to the outside air.

The water-absorbing material 15 has a structure in which water-absorbing granules 16 such as a water-absorbing polymer and silica gel are accommodated in a bag 17 of water-permeable and breathable chemical fiber. Further, the bag 17 is a long object having a length that is spirally wound from the outermost portion to the inside of the wire harness W / H. The long bag 17 is divided into small bags 17a, and the small bags are divided into small bags 17a. 17a is continuous. When divided into the small bags 17a in this way, the internal granules 16 can be evenly distributed. The bag 17 may be formed of a nonwoven fabric.

In the method of assembling the grommet having the waterproof function, first, in the step of forming the wire harness W / H for converging the electric wire w, the flexible sheet-shaped water absorbent material 15 is spirally wound. , This is a wire harness W / H
Grommet 10 from medium diameter portion 11-1 to large diameter portion 11-2
And to be bundled with the electric wire at the part to be arranged. Next, the wire harness W / H is made to penetrate the grommet 10 in a state where the small-diameter cylindrical portion 12 of the grommet 10 is expanded by a diameter expander (not shown), and the medium-diameter portion 11-1 of the expanded portion 11 of the grommet 10. And the large-diameter portion 11-2 is provided with a portion in which the sheet-shaped water-absorbing material 15 of the wire harness W / H is wound. Thereafter, a water-stopping agent is filled in the enlarged diameter portion 11 to form a water-stopping agent layer 14. Note that the water stopping agent may be filled in the enlarged diameter portion 11 first, and the wire harness W / H may be penetrated through the grommet 10 while the water stopping agent is not yet cured.

As shown in FIG. 5, the grommet 10 having the wire harness W / H having the above-described configuration is mounted in a through hole 1a of a vehicle body panel 1 that separates an outside X and an inside Y of an engine room in an automobile. Is done. That is, the vehicle body locking groove 13 on the outer peripheral surface of the enlarged diameter portion 11 is inserted into the through hole 1a.
, The small-diameter cylindrical portion 12 is set to the outdoor X side, and the open end of the large-diameter portion 11 is mounted to the indoor Y side. Therefore, the other portion 15b of the water absorbing material 15 attached inside the enlarged diameter portion 11 is exposed to the air on the indoor side.

Even if the waterproofing agent filled between the wire groups constituting the wire harness W / H is deteriorated and a gap is generated between the wire groups, the outdoor X on the engine room side is passed through the gap.
The more water that invades is absorbed by the sheet-like water-absorbing material 15 spirally wound around the wire harness W / H, so that it is possible to prevent water from entering the room Y. Also, even if the outer peripheral surface of the wire group constituting the wire harness W / H separates from the water-blocking agent layer 14 and a gap is generated, moisture entering from the outdoor X on the engine room side through this gap does not The water is absorbed by the sheet-like water-absorbing material 15 disposed on the outer peripheral surface of the group, and it is possible to prevent water from entering the room Y. Specifically, water is immersed in the bag 17 from the bag 17 of the water-absorbing material 15, comes into contact with the water-absorbing granules 16 in the bag 17, and is absorbed by the granules 16.

Since the other portion 15b of the water-absorbing material 15 in the form of a spiral is exposed to the outside air without contacting the water-stopping agent layer 14, the water absorbed by the granules 16 is evaporated, The granules 16 are dried so that the granules 16 do not become saturated with water. As described above, the water that has entered the grommet from the outside is absorbed by the sheet-shaped water-absorbing material 15, and then the absorbed water is evaporated and dried. Prevention can be achieved.

FIGS. 6 to 8 show a second embodiment. In the present embodiment, one end of each of six short sheet materials 19 in which water-absorbing granules 16 such as a water-absorbing polymer and silica gel are accommodated in a short chemical fiber bag 18 having water permeability and air permeability is sewn. Alternatively, a water-absorbing material 20 having a configuration in which the sheet material 19 is fastened together using an adhesive and the other ends of the respective sheet members 19 are radially spread around the fastening portion is used.
0 is the middle diameter part 1 of the grommet 10 of the wire harness W / H
1-1 to the large diameter portion 11-2 (see FIG. 1), the wire harness W / H penetrates into the grommet 10 and the water-stopping agent layer as in the first embodiment. 14 was formed. The bag 18 has substantially the same length as the radius of the wire harness W / H,
It is divided into small bags 18a, and the small bags 18a are continuously formed to have a length substantially equal to the radius of the wire harness W / H.

The incorporation of the water-absorbing material 20 into the wire harness W / H is performed by combining the wire harness W / H that bundles a plurality of electric wires.
In the step of preparing / H, a gap is provided in the wire bundle, a water absorbing material 20 obtained by folding six sheet materials 19 is inserted into the gap, and the sheet material 19 is radially spread in the wire bundle. The water-absorbing material 20 has a portion 19a in the direction perpendicular to the radiation direction of the sheet material 19 contacted with the inner peripheral surface of the waterproofing agent layer 14 and the waterproofing agent filled between the electric wires w of the wire harness W / H. The other portion 19b is projected from the surface 14a of the waterproofing agent layer 14 to be exposed to the outside air.
The distal end 19c of the sheet member 19 in the radial direction projects from the outer peripheral surface of the wire harness W / H.

[0024] Even if the water blocking agent filled between the electric wires constituting the wire harness W / H is deteriorated and a gap is generated between the electric wires, the outdoor X on the engine room side is passed through the gap.
The more water that invades is absorbed by the water absorbing material 20 incorporated in the wire harness W / H, so that it is possible to prevent water from entering the room Y. Further, even if a gap is generated due to the outer peripheral surface of the electric wire group constituting the wire harness W / H and the water-blocking agent layer 14 being separated from each other, the water enters through the gap from the outdoor X on the engine room side. Moisture is absorbed by the sheet material 19c protruding from the outer peripheral surface of the electric wire group, and it is possible to prevent water from entering the room Y.

In the above-described embodiment, the grommet has a large-diameter portion having two large diameter portions, that is, a middle diameter portion and a large diameter portion. However, the grommet is not limited to such a shape, but extends conically from the small diameter tube portion. The grommet may be provided with a large-diameter portion having only one large-diameter portion, and the water-absorbing material may be disposed along the inner peripheral surface of the large-diameter portion of the grommet.

[0026]

As is apparent from the above description, according to the present invention, between the electric wires and between the inner peripheral surface of the enlarged portion of the grommet and the outer peripheral surface of the waterproofing agent layer in the enlarged portion of the grommet. Because the water-absorbing material is interposed, the water-stopping agent deteriorates, and even if there is a gap between the electric wires or between the grommet and the inner peripheral surface of the enlarged-diameter portion, the water that has entered the gap absorbs water. Water can be absorbed by the material to prevent ingress into the room.

Furthermore, since a part of the water absorbing material is exposed to the outside air without contacting the water-stopping agent layer, the absorbed water is evaporated so as not to be in a saturated state, so that the water absorbing performance is always utilized. As a result, it is possible to absorb the inundated water, and almost completely prevent ingress of water into the room.

[Brief description of the drawings]

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

FIG. 2 is a perspective view of FIG.

FIG. 3 is a sectional view taken along line III-III of FIG. 1;

FIG. 4 is a perspective view of the water absorbing material of FIG. 1;

FIG. 5 is an enlarged view of a main part of FIG. 1;

FIG. 6 is a sectional view showing a second embodiment of the present invention.

FIG. 7 is a perspective view of the water absorbing material of FIG. 6;

FIG. 8 is a sectional view taken along line VI-VI of FIG. 6;

FIG. 9 is a cross section showing a conventional example.

FIG. 10 is a sectional view showing another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Grommet 11 Large-diameter part 12 Small-diameter pipe part 13 Car body locking groove 14 Waterproofing agent layer 15, 20 Water-absorbing material 16 Granules 17, 18 bags

Claims (4)

[Claims] 1. A wire harness is inserted into a through hole formed in a panel that separates the interior and exterior of an automobile through a grommet including an enlarged diameter portion and a small diameter cylindrical portion, and the grommet is filled with a waterproofing agent. In the waterproofing structure, a portion of the wire harness arranged in the enlarged diameter portion is
While a water absorbing material is interposed between the bundled electric wires, a part of the water absorbing material is brought into contact with the water blocking agent layer filled in the enlarged diameter portion, and the other portion is connected to the water stopping agent layer. A waterproof structure for an automobile wire harness, wherein the waterproof structure is made to protrude to the outside so as to be exposed to the outside air so that the moisture of the water absorbing material is not saturated. 2. A long flexible sheet-like material in which water-absorbing particles such as a water-absorbing polymer and silica gel are contained in a water-permeable and breathable fiber bag. 2. The automobile wire harness according to claim 1, wherein the long flexible sheet-like material is spirally wound, and an electric wire is arranged between opposed sheet surfaces of the wound material. Waterproof structure. 3. The water-absorbing material includes a plurality of short flexible sheet-like materials each containing water-absorbing particles such as a water-absorbing polymer and silica gel in a water-permeable and air-permeable fiber bag. One end of each of the plurality of short flexible sheet-like objects is fastened together and fastened together, and the other end of each sheet-like material is radially spread around the fastening portion and arranged. The waterproof structure of a wire harness for an automobile according to claim 1, wherein an electric wire is arranged between adjacent sheets of the plurality of flexible sheets arranged radially. 4. The waterproof structure of a wire harness for an automobile according to claim 2, wherein the bags are divided into small bags and are continuous in the length direction.