JP3116837B2 - Grommet waterproof structure and waterproofing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof structure and a waterproof method for a grommet to be mounted in a state where a wire harness is inserted into a through hole of a vehicle body panel or the like. The purpose of the present invention is to make the grommet waterproof without improving the workability and reducing the cost.

[0002]

2. Description of the Related Art When an automobile wire harness is wired from the engine room side through the through hole of a vehicle body panel to the interior side, a cylindrical small-diameter cylindrical portion and an enlarged large-diameter cylindrical portion are communicated with each other. The wire harness is inserted through a rubber grommet having the formed wire insertion portion, and in this state, the grommet is attached to the through hole to achieve waterproofing.

[0003] In order to enhance the waterproofness of the grommet, there have been proposed various types of grommet in which a liquid curable sealing agent is filled into the grommet and the sealing agent is allowed to penetrate between electric wires (for example, Japanese Patent Application Laid-Open No. Hei 6-1994). No. 223611).

[0004]

However, in the case of using the above-mentioned sealant, as shown in FIG. 4, the grommet 1 having the wire harness W / H inserted therein is held vertically while the grommet 1 is sealed in the grommet 1. Equipment for injecting the agent 3 by a fixed amount is required. In addition, the grommet 1 must be left standing for a predetermined period of time while maintaining the vertical state until the sealing agent 3 filled in the grommet 1 solidifies. In addition, there were problems such as poor productivity.

Since the sealant 3 is of low viscosity and has high fluidity so that it can sufficiently penetrate into the gap between the electric wires, the sealant 3 is provided on the outer peripheral surface of the small diameter cylindrical portion 4 at the lower end of the grommet 1. Has a tape T wound in a half-wrap shape over a range of about 100 or more in order to prevent leakage of the sealant 3 from the small-diameter cylindrical portion 4. For this reason, the wire harness W / H on the side of the small-diameter cylindrical portion 4 is enlarged, the flexibility is deteriorated, the degree of freedom of wiring is reduced, and a separate work for winding the tape is required. It also took a lot of trouble in terms of

[0006]

In order to solve the above-mentioned problems, the present invention is directed to a first aspect of the present invention, wherein a grommet for inserting a wire harness comprising a group of wires is inserted into a wire insertion portion in a direction perpendicular to the direction in which the wires are inserted. A disk-shaped spacer is disposed, a first putty layer is disposed in close contact with the outer peripheral surface of the spacer, and the electric wires of the electric wire group are dispersed and pushed into the first putty layer. A second putty layer is disposed, the wire is buried and penetrated between the first putty layer and the second putty layer, and an inner periphery of the wire insertion portion is provided on an outer peripheral surface of the second putty layer. It provides a grommet waterproof structure characterized in that the surfaces are in close contact.

[0007]

In order to solve the above-mentioned problems, the present invention is directed to a first aspect of the present invention, wherein a grommet for inserting a wire harness comprising a group of wires is inserted into a wire insertion portion in a direction perpendicular to the direction in which the wires are inserted. Arrange a disk-shaped spacer,
A putty layer is disposed in close contact between the outer peripheral surface of the spacer and the inner peripheral surface of the wire insertion portion, and the wires of the wire group are dispersed to penetrate the inside of the putty layer. Offers grommet waterproof structure.

In the grommet, the small-diameter tubular portion, the medium-diameter tubular portion, and the large-diameter tubular portion that are in close contact with the outer peripheral surface of the electric wire group are successively formed, and the electric wire insertion portion is formed along the axis thereof. A spacer around which the putty through which the electric wire passes is wound around the outer peripheral surface is disposed on the middle diameter cylindrical portion (claim 2).

[0009] With the above configuration, the electric wires constituting the wire harness are spread through the spacer and are arranged in a putty layer provided on the outer peripheral surface of the spacer in a dispersed state, so that the distance between the electric wires is reduced. It is covered with putty without gaps. Then, in this state, the putty adheres to the outer peripheral surface of the spacer and the inner peripheral surface of the wire insertion portion due to its adhesiveness, so that waterproofness between the small-diameter tubular portion and the large-diameter tubular portion of the grommet is ensured. be able to.

According to the present invention, a wire harness composed of a plurality of electric wires is pushed and spread at a predetermined position, and a band-shaped putty is wound in the space to form a first putty layer on an outer peripheral surface. Is inserted in the direction perpendicular to the electric wires, and the electric wires are dispersed and pushed onto the first putty layer, and a band-like putty is wound around the outer peripheral surface of the first putty layer. And placing a second putty layer, applying pressure to the second putty layer from the outer peripheral direction, and burying the wire between the first and second putty layers,
In this state, the grommet waterproofing method is provided, wherein the wire harness is disposed in the wire insertion portion of the grommet, and the outer peripheral surface of the second putty layer is adhered to the inner peripheral surface of the wire insertion portion. ing.

[0011] According to the structure of the third aspect, the wire harness composed of a plurality of electric wires is dispersed and embedded between the first and second putty layers on the outer peripheral surface of the spacer.
The gap between the wires can be covered with putty to ensure sufficient waterproofness. The work can be easily performed only by hand, due to the properties of the putty having plasticity and adhesiveness. Thus, the use of the putty makes it possible to eliminate the need for a liquid curable sealant.

It is preferable that a plurality of slits are formed on the surface of the first putty layer in parallel with the direction in which the electric wires are inserted, and the electric wires are pushed into the slits. As described above, when a plurality of slits are formed on the surface of the first putty layer, the wires can be dispersed by being guided by the slits, and can be kept in that state until the second putty layer is wound. Since the electric wires can be held, workability can be further improved.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the grommet waterproof structure of the first embodiment has a spacer 11 disposed inside a grommet 10, and a putty layer 12 provided in a layer on the outer peripheral surface of the spacer 11. The electric wires W of the wire harness W / H penetrate the putty layer 12 in a distributed manner.

The grommet 10 is made of rubber or an elastomer, and has a cylindrical small-diameter cylindrical portion 10a and an expanded medium-diameter cylindrical portion 10a connected to one end of the small-diameter cylindrical portion 10a.
c, the large-diameter cylindrical portion 10 expanded from the tip of the medium-diameter cylindrical portion 10b
b, and an electric wire insertion portion 10f is formed by an internal space communicating with each portion in the axial direction. In the large-diameter cylindrical portion 10b, a locking groove 10e that engages with a through hole of a vehicle body panel (not shown) is annularly formed on the outer peripheral surface on the opening 10d side.

The spacer 11 is shown in FIGS. 2A and 2B.
As shown in the figure, the spacer 11 is formed in a disk shape with a synthetic resin.
The diameter is set smaller than the inner diameter of c by the thickness of the putty layer 12.
On the outer peripheral surface of the spacer 11, as shown in FIG. 2, a rough or uneven anti-slip portion 11a is formed.
The compatibility with the putty layer 12 is improved.

The putty layer 12 includes a first putty layer 12A in which a putty having plasticity and tackiness is arranged on the outer peripheral surface of the spacer 11, and a wire W on the outer peripheral surface of the first putty layer 12A. And the second putty layer 12B. As shown in FIG. 2A, the first putty layer 12
In A, a putty was formed in a strip shape having substantially the same width as the spacer 11, a release paper 12c was provided on the back surface, and a plurality of slits 12d were formed on the front surface in a direction parallel to the insertion direction of the wires W to be dispersed and arranged. It is composed of the first putty member 12a. The second putty layer 12B is formed of a second putty member 12b provided with a release paper 12c on the back side, and is wound around the outer periphery of the first putty member 12a, similarly to the first putty layer 12A. The length is formed as much as the length. Note that, specifically, the first and second putty members 12a, 12b are each formed to a thickness of approximately 3 mm.

Next, the first and second putty members 12a, 1
A grommet waterproofing method using 2b will be described.
As shown in FIG. 2A, first, the release paper 12c on the back surface of the first putty member 12a is peeled off, the first putty member 12a is wound around the outer peripheral surface of the spacer 11, and the first putty member 12a is placed on the spacer 11. One putty layer 12A is arranged.

Next, as shown in FIG. 3 (A), the wire harness W / H previously bound on the assembly drawing board of the wire harness W / H is placed at the position where the grommet 10 is attached to the electric wire W / H.
Is inserted into the space portion 13 formed by pushing and spreading the first putty layer 12A in a direction perpendicular to the electric wire W. At this time, the plurality of slits 12d formed on the surface of the first putty member 12a are recessed in a V-shaped cross section in the wound state on the spacer 11, so that each wire is inserted into the slit 12a. The electric wires W are arranged in a dispersed state on the first putty layer 12A so that W is pushed in.

Next, as shown in FIG. 3 (B), the adhesive surface of the second putty member 12b is wound around the outer peripheral surface of the first putty layer 12A having the wires W dispersedly arranged on the surface. The second putty layer 12B. Then, FIG. 3 (C)
As shown in the figure, a manual operation or a jig (not shown) is performed from the outer periphery of the second putty layer 12B toward the spacer 11.
Pressure is evenly applied to the entire circumference with the first putty layer 12 and the like.
A between the first putty layer A and the second putty layer 12B,
The gap between them is covered with putty to ensure waterproofness.

Next, on the outer periphery of the spacer 11, first,
The wire harness W / H in which the electric wire W is embedded between the second putty layers 12A and 12B is inserted into the grommet 10. At that time, first, the release paper 12c of the second putty member 12b is peeled off to expose the outer peripheral adhesive surface of the second putty layer 12B, and then the small-diameter cylindrical portion 10a of the grommet 10 is spread by a grommet spreader (not shown). The diameter is enlarged to penetrate the wire harness W / H. Then, the first and second putty layers 12A, 12B
The spacer 11 having the outer periphery arranged on the outer periphery thereof is
c, and is positioned so that the outer peripheral surface of the second putty layer 12B is in close contact with the inner peripheral surface of the middle half cylindrical portion 10c. In this state, the medium-diameter cylindrical portion 10c is sealed by the spacer 11 and the putty layer 12, and the wires W are also embedded so as to penetrate the putty layer 12. Waterproofing is provided between the cylindrical portion 10a and the large-diameter cylindrical portion 10b.

As shown by a two-dot chain line in FIG. 1, the inner peripheral surface of the medium-diameter cylindrical portion 10c of the grommet 10 is engaged with the end surface of the spacer 11 for positioning the spacer 11. The protrusions 14 may be provided at appropriate intervals.

[0023]

As is apparent from the above description, in the grommet waterproofing structure and the waterproofing method of the present invention, the space between the wire insertion portion of the grommet and the spacer and between the wires are sealed via the putty layer. Can be waterproofed. Therefore, there is no need to fill with a liquid curable sealant as in the related art, and no equipment for filling the sealant, no waiting time until the sealant is cured, and no space for leaving the wire harness during that time are required. Becomes Furthermore, since it is not necessary to wind the tape around the small-diameter cylindrical portion for preventing leakage of the sealant, the wire harness is not enlarged and the degree of freedom of the wiring is not reduced. Also, putty,
Since it is a plastic solid, its handling is easy, and it is possible to apply pressure for winding around a spacer and burying an electric wire only by manual operation.

In particular, in the present invention, it is not necessary to fill a liquid curable sealant, so that the manufacturing equipment can be simplified and the workability can be greatly improved. The manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first embodiment.

FIG. 2A is a perspective view of a spacer and a putty member,
(B) is a perspective view which shows the winding state of a putty member.

FIGS. 3A and 3B are explanatory views showing a process of attaching a spacer and a putty member to a wire harness, and FIG. 3C is a sectional view of a main part of FIG.

FIG. 4 is a cross-sectional view showing a conventional grommet waterproof structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Grommet 10c Medium diameter cylindrical part 10f Electric wire insertion part 11 Spacer 12 Putty layer 12A First putty layer 12B Second putty layer W / H Wire harness W Electric wire

Claims (4)

(57) [Claims] A disc-shaped spacer is disposed in a wire insertion portion of a grommet for inserting a wire harness composed of a wire group in a direction orthogonal to a wire insertion direction, and a first putty layer is provided on an outer peripheral surface of the spacer. Is placed in close contact with the above
The wires of the wire group are dispersed and pushed into the first putty layer
The second putty layer is disposed on the outer peripheral surface of the first putty layer.
The wire is buried between the te layer and the second putty layer and
The outer periphery of the second putty layer is provided on the inner periphery of the wire insertion portion.
A grommet waterproof structure characterized in that the surfaces are in close contact . 2. The grommet according to claim 1, wherein the small-diameter tubular portion, the medium-diameter tubular portion, and the large-diameter tubular portion that are in close contact with the outer peripheral surface of the wire group are successively connected to each other. The grommet waterproof structure according to claim 1, wherein a spacer, which is formed and has a putty on which the electric wire penetrates wound around the outer peripheral surface, is disposed on the middle diameter cylindrical portion. 3. A circle in which a wire harness composed of a group of electric wires is pushed and spread at a predetermined position to form a hollow portion, and a band-shaped putty is wound in the hollow portion, and a first putty layer is arranged on the outer peripheral surface. After inserting a plate-shaped spacer in a direction orthogonal to the electric wires, dispersing and pushing the electric wires onto the first putty layer,
The second putty layer is disposed by winding a band-like putty on the outer peripheral surface of the putty layer, and pressure is applied to the second putty layer from the outer peripheral direction to place an electric wire between the first and second putty layers. A method of waterproofing the grommet, wherein the wire harness is buried, and in this state, the wire harness is disposed in the wire insertion portion of the grommet, and the outer peripheral surface of the second putty layer is in close contact with the inner peripheral surface of the wire insertion portion. . 4. The grommet according to claim 3, wherein a plurality of slits are formed on a surface of said first putty layer in parallel with a wire insertion direction, and the wires are pushed into said slits. Waterproof method.