JPH06150757A - Grommet waterproof structure - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a grommet waterproof structure having an excellent waterproof effect and easy to assemble. [Structure] An inner chamber of a resin cover 10 made of a half-cylindrical body is filled with a sealing material 9 having permeability and waterproofness, and a wire bundle 3 is inserted. After tape winding is applied to the end of the resin cover 10 and a part of the electric wire bundle 3 adjacent to the end,
The resin cover 10 is fitted into the small opening cylinder portion 4 of the grommet 1. The waterproof structure is completed by tape-wrapping the small opening tubular portion 4 and the exposed portion of the resin cover 10 and a part of the electric wire bundle 3 adjacent to the resin cover 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a case where a wire harness is routed from one room (for example, an engine room of a car) to the other room (for example, a car room) through a panel for partitioning the two rooms, The present invention relates to a grommet waterproof structure mounted on a panel.

[0002]

2. Description of the Related Art For example, when wiring a wire harness between an engine room and a vehicle compartment of an automobile, an insertion hole is formed in a dash panel that separates both rooms, and a grommet is attached to the insertion hole. Wiring was performed by inserting an electric wire inside the grommet.

At this time, in order to prevent water that has entered the engine room due to running in the rain or washing the car from traveling along the electric wire and entering the passenger compartment side, and reaching the connector portion at the end of the electric wire, the electric wire and the grommet are separated from each other. , Waterproofed by sealing material. A waterproof structure for such a grommet is shown in FIG.
6 and the one shown in FIG.
327).

The grommet 1 comprises a large opening tubular portion 2 at one end and a small opening tubular portion 4 having an inner diameter such that the electric wire bundle 3 can be inserted at the other end. The large opening tubular portion 2 and the small opening tubular portion 4 are formed. It has a structure in which it is integrally connected by a tubular member 5 having elasticity. Further, a fitting groove 6 for mounting on a panel (not shown) is annularly provided on the outer peripheral wall surface of the tubular member 5. Further, an inner cylinder 7 having a hollow portion communicating with the hollow portion of the small opening tubular portion 4 is formed in the space formed by the tubular member 5 and the large opening tubular portion 2.

In the waterproofing process, first, the electric wire bundle 3 is inserted into the small opening cylindrical portion 4 of the grommet 1 and the hollow portion of the inner cylinder 7, the grommet 1 is positioned on the electric wire bundle 3, and then the small portion of the grommet 1 is inserted. The open tubular portion 4 and the electric wire bundle 3 adjacent to the open tubular portion 4 are tape-wound with a fixing tape 8 such as a vinyl tape to temporarily fix the electric wire bundle 3 and the grommet 1. Then, the inner tubular portion 7 of the large open tubular portion 2 side is fixed. A sealing material 9 having permeability and water resistance is injected from the end. The sealing material 9 is made of a liquid resin or rubber which has a curability over time due to a reaction or the like, and as shown in FIG. 6 (AA ′ sectional view of FIG. 5),
The gap between the electric wires of the electric wire bundle 3 and the electric wire bundle 3 and the small opening tubular portion 4
(And the inner cylinder 7) is permeated and filled in the gap, and the gap is sealed by hardening.

The waterproof grommet 1 is mounted in the insertion hole (not shown) of the panel by the fitting groove 6.

[0007]

However, in the waterproof structure of the grommet 1 having the structure shown in FIGS. 5 and 6,
After inserting the wire bundle 3 into the grommet 1, positioning and temporarily fixing with the fixing tape 8, that is, the grommet 1
Since the sealing material 9 has to be injected and filled after the work of assembling the wire bundle 3 and the electric wire bundle 3, it is necessary to remove the grommet 1 from the assembly jig once at the time of injecting the sealing material 9, which lowers the workability. Or a work space for that purpose must be secured.

Further, in order to inject the sealing material 9 from the outside after the assembling, the injected sealing material 9 is uniformly filled inside the hollow portions of the inner cylinder 7 and the small opening cylindrical portion 4 to every corner of the gap. It is difficult to determine whether or not it is being injected,
The filling rate of the sealing material 9 inside the hollow portion becomes non-uniform due to the excess or deficiency of the injection amount of the sealing material 9, and as a result, the waterproof effect varies, which causes problems such as deterioration of product quality and yield.

An object of the present invention is to make the grommet 1 in which the sealing material 9 is easily injected, and it is not necessary to secure a working space therefor, and there is no variation in the waterproof effect due to an excessive or insufficient amount of the sealing material 9 injected. To obtain a waterproof structure.

[0010]

[Means for Solving the Problems] The above-mentioned problem has elasticity in which one end is formed as a large opening cylinder portion and the other end is formed as a small opening cylinder portion, and a fitting groove is annularly provided on the outer peripheral surface of the large opening cylinder portion. In a grommet waterproof structure including a tubular body, a grommet main body and a hollow resin cover that is fitted into the grommet main body and closely adheres to the small opening tubular portion, and the resin cover has permeability and water resistance inside. This is solved by the waterproof structure of the grommet, which is filled with the sealing material that it has and is formed in a split shape so that the electric wire bundle can be inserted therethrough.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a grommet waterproof structure according to the present invention will be described below with reference to the accompanying drawings. However, the waterproof structure of the grommet according to the present invention is not limited to this embodiment, and various modifications can be made. As shown in FIG. 1, the grommet 1 includes a large opening tube portion 2 at one end and a small opening tube portion 4 having an inner diameter such that the wire bundle 3 can be inserted at the other end. The open tubular portion 4 is integrally connected by a tubular member 5 having elasticity. Further, a fitting groove 6 for mounting on a panel (not shown) is annularly provided on the outer peripheral wall surface of the tubular member 5.

The wire bundle 3 has a structure which will be described later, and is inserted into a resin cover 10 in which a sealing material 9 is filled. The resin cover 10 is inserted into the small opening cylinder portion 4 of the grommet 1, and the grommet 1 is formed by the pressure contact force between the outer wall surface of the resin cover 10 and the inner wall surface of the small opening cylinder portion 4.
In close contact with. The resin cover 10 is made of a synthetic resin material having excellent weather resistance and insulating properties, and as shown in FIG.
It is composed of 2a and 12b. In addition, the flat portion 13
Semi-cylindrical wire bundle holding portions 14a and 14b having an inner diameter that allows the wire bundle 3 to be inserted are formed concentrically on a and 13b.

Further, the semi-cylindrical bodies 12a and 12b of the resin cover 10 and the opposite edges thereof are formed with the semi-cylindrical bodies 12a and 12b by associating and closing both semi-cylindrical bodies. Sometimes (see FIG. 4), stepped portions 16a and 16b that form the slit-shaped opening 15 are formed along the longitudinal direction of the cylindrical surface of the cylindrical body. The present invention waterproofs the grommet 1 using the resin cover 10 having such a structure.
The procedure will be described below.

As shown in FIG. 3, first, the inner chambers of the semi-cylindrical bodies 12a and 12b of the resin cover 10 are filled with a sealing material 9 having permeability and water resistance. The sealing material 9 is
It is made of gel-like resins or rubbers such as butyl rubber. Next, the wire bundle 3 is placed on the liquid surface of the seal material 9 of the one half cylinder 12b filled with the seal material 9 along the wire bundle holding portion 14b.

After placing the wire bundle 3, the other half cylinder 12a
Is rotated about the hinge 11 to meet and close the half-cylindrical body 12b on the side on which the electric wire bundle 3 is placed, to form a cylindrical body in which the electric wire bundle 3 is inserted as shown in FIG. To do. Here, the engagement between the half cylinders can be more firmly held by providing the flat pieces 13a and 13b of the half cylinders with the engaging pieces 16 that are engaged at the time of meeting.

At the time of assembly of the semi-cylindrical bodies, the sealing material 9 filled in the semi-cylindrical bodies permeates the gap between the electric wires of the electric wire bundle 3 and a part thereof overflows into the electric wire bundle holding portions 14a, 14b. The remaining portion overflows from the opening 15 to the outside of the resin cover 10. The openings 15 do not have to be provided at two locations, one on the side where the hinge 11 is formed and the other side, and either one may be provided.

In this way, inside the resin cover 10,
Moreover, the space between the inserted wires of the wire bundle 3 can be filled with the sealing material 9 without any gap. After forming the tubular body, the electric wire bundle holding portions 14a and 14b and a part of the electric wire bundle 3 adjacent to the electric wire bundle holding portion 14a and 14b are tape-wound with a fixing tape 8 such as a vinyl tape, and the electric wire bundle holding portions 14a and 14b and the electric wire bundle 3 are separated from each other. More airtight.

After that, the resin cover 10 with the wire bundle 3 thus inserted is fitted and closely fitted to the inner wall of the small opening cylindrical portion 4 of the grommet 1 as shown in FIG. Here, on the outer wall surface of the resin cover 10, for example, a projection-shaped positioning member 17 is integrally formed over the entire circumference of the cylindrical surface of the resin cover 10, and the resin cover 10 is fitted into the small opening tubular portion of the grommet 1. 4 from the right side in the drawing until it comes into contact with the end portion 18 of the small opening tubular portion 4, so that the grommet 1
Thus, the resin cover 10 can be positioned.

After the resin cover 10 is positioned and inserted into the grommet 1, the small opening tubular portion 4 and the portion of the resin cover 10 exposed from the small opening tubular portion 4 to the outside and the resin cover 10 are attached. Adjacent electric wire bundles 3 are wound with a fixing tape 8 to enhance airtightness. With the above, the waterproof structure of the grommet 1 is completed.

[0020]

With such a waterproof structure, as shown in FIG.
(AA 'cross-sectional view), the wire bundle 3 inserted into the grommet 1 is sealed by the sealing material 9 inside the resin cover 10 over the gap between the wires and the entire periphery of the wire bundle 3. Therefore, it is possible to completely block the water that has entered the electric wires of the electric wire bundle 3 and invaded.

The portion of the grommet 1 of the resin cover 10 fitted in the small opening tubular portion 4 is firmly adhered by the pressure contact force between the inner wall of the small opening tubular portion 4 and the outer wall of the resin cover 10, and the grommet Since the portion exposed to the outside of 1 is tape-wrapped, the resin cover 10
It is possible to block water entering from the boundary between the grommet 1 and the wire bundle 3.

Further, since the joining portion and the opening portion 15 at the end edges of the semi-cylindrical bodies 12a and 12b of the resin cover 10 are sealed by the sealing material 9, water may enter the inside of the resin cover 10 from that portion. Absent. As described above, according to the grommet waterproof structure of the present invention, the resin cover 10
Since the grommet 1 and the grommet 1 are in surface contact with each other, the conventional wire bundle 3
As compared with the seal structure between the grommet 1 and the grommet 1, since the adhesion is improved, it is possible to completely block the water that enters along the electric wire and the water that enters from the boundary between the grommet 1 and the wire bundle 3. it can.

Further, the amount of the sealing material 9 for sealing the wire bundle 3 can be visually confirmed when the wire bundle 3 is inserted into the resin cover 10, and the excess sealing material 9 overflows from the opening 15. Since the structure is made possible, it is possible to avoid a decrease in the waterproof effect due to the insufficient filling amount of the sealing material 9, and it is possible to obtain a product in which the sealing material 9 is always filled uniformly.

Further, in the present invention, since the electric wire bundle 3 is inserted through the resin cover 10 which is previously filled with the sealing material 9, and then the resin cover 10 is inserted into the grommet 1, the sealing material 9 is inserted.
It is not necessary to remove it from the jig once, as in the conventional case, and this is extremely advantageous in workability and work space.

[Brief description of drawings]

FIG. 1 is a diagram showing a waterproof structure of a grommet according to the present invention.

FIG. 2 is a grommet waterproof structure A- shown in FIG.
It is an A'sectional view.

FIG. 3 is a diagram showing a resin cover used in the waterproof structure of the grommet shown in FIG. 1 and a diagram for explaining a method of inserting the electric wire bundle.

FIG. 4 is a view showing a state in which the resin cover 1 shown in FIG. 3 is closed.

FIG. 5 is a view showing a conventional grommet waterproof structure.

6 is a grommet waterproof structure A- shown in FIG.
It is an A'sectional view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Grommet 2 Large opening cylinder part 3 Wire bundle 4 Small opening cylinder part 5 Cylindrical member 6 Fitting groove 7 Inner cylinder 8 Fixing tape 9 Sealing material 10 Resin cover 11 Hinge 12a, 12b Half cylinder body 13a, 13b Flat surface part 14a, 14b Wire bundle holding portion 15 Opening portions 16a, 16b Step portion 17 Positioning member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuhiro Ito 2464-48 Washizu, Kosai City, Shizuoka Prefecture, Yazaki Parts Co., Ltd.

Claims (1)

[Claims] 1. An elastic tube body, one end of which is formed into a large opening tube portion and the other end of which is formed into a small opening tube portion, and a fitting groove for fitting a panel or the like is provided on the outer peripheral surface of the large opening tube portion. In the waterproof structure of the grommet, the grommet main body and a hollow resin cover fitted into the grommet main body and in close contact with the small opening tubular portion are formed, and the resin cover has a sealing material having permeability and water resistance inside. A waterproof structure for grommets, which is filled and formed in two pieces so that a bundle of electric wires can be inserted therethrough.