JPH11238416A - Waterproofing method of wire harness and waterproof structure of wire harness inserting grommet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a perfect waterproof with a relatively easy process at a low cost by applying a water stopping agent having a required viscosity so as to penetrate between wires of a position subjected to wire-to-wire waterproof in the laying of wire groups in the assembly of a wire harness, inserting a resin bar to this part, winding a sheet, and inserting it into a grommet in the state rolled into a circular section. SOLUTION: To a wire passed through a pair of wire holding members 14, 15 on the substrate of a waterproofing jig on a work bench for wire harness assembling, a silicon water stopping agent 5 having a viscosity of 1,000-2,000 poise is applied by an applicator 26. Atter a waterproofing jig is lowered, a foamed sheet 7 put after the insertion of a resin bar 6 between the wire groups W is rolled into a circular section and inserted to a grommet 1. The circumferential surface of the wire groups W may be wound by a sheet 1. According to this, the water stopping agent 5 can be applied between the wires W without being performed as a separate process as in the application of a two-liquid urethane agent, or flowing or diffusion of the water stopping agent. Further, the bending and the adhesion of the water stopping agent 5 to the hand of a worker can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproofing method for waterproofing between wires of a wire harness to be inserted into a mounting grommet into a panel through hole of an automobile, and a waterproof structure of a wire harness insertion grommet made by the method. Things.

[0002]

2. Description of the Related Art In a wiring harness for a vehicle, when wiring the wiring harness through a panel or the like that separates an engine room and a vehicle compartment of the vehicle, a grommet made of rubber or an elastomer is attached to a through hole formed in the panel. A wire harness is wired through the grommet to prevent water from entering the cabin. The grommet is provided with a panel locking portion on the outer peripheral surface of the enlarged diameter portion having a substantially conical cylindrical shape, and the panel locking portion is locked to the inner peripheral edge of the panel through hole, so that the gap between the grommet and the panel through hole is secure. The wire harness is passed through the small diameter pipe portion extending to the reduced end side of the enlarged diameter portion through the grommet while waterproofing.

If there is a gap between the electric wires of the wire harness through which the grommet is inserted and between the electric wires and the small-diameter pipe portion of the grommet, water enters the vehicle compartment from the engine room side through the gaps. Also need to be sealed.

As a waterproof structure between lines, as shown in FIG.
Is provided to infiltrate each gap of the electric wire w. Alternatively, using an elastic cap having a plurality of holes through which each wire of the wire harness is inserted one by one, fitting the elastic cap into the tube of the grommet with the wires being passed through the holes in the elastic cap, There is also provided a method of filling a flowable sealant from the inside to the inside of an elastic cap. (Japanese Utility Model Application Laid-Open No. 1-66713, Japanese Utility Model Application Laid-Open No. 2-1)
No. 15221, Japanese Utility Model Laid-Open No. 4-23812)

[0005]

In the case of the former waterproof structure shown in FIG. 6, if the fluid sealing material does not have a low viscosity (for example, 100 cps or less), it does not easily penetrate into the gaps between the electric wires. If there is, there is a possibility that it will flow out of each gap until it is cured, so that complete waterproofing cannot be expected. Therefore, generally, a grommet is attached to a predetermined position of the wire harness W / H as shown in FIG. 1 is filled while mixing two-component urethane and the like, and is cured after filling.

However, it is troublesome to use a mixture of two components such as two-component urethane, and the solution mixed at one time is easily cured in the air.
Very difficult to handle. In addition, there is a problem in that the equipment for mixing the two liquids is large-sized and cannot be operated on a wire harness assembly line, and a separate process must be provided to fill the sealant.

In addition, when the above-mentioned elastic cap is used, a gap is reliably formed between the electric wires, so that even if the fluid sealing material has a high viscosity, it easily penetrates into the gap between the electric wires to achieve complete waterproofing. However, in addition to the need for an elastic cap as a separate component, the number of steps of inserting each electric wire through the cap and the step of fitting the cap into the grommet increases, which is troublesome and increases the cost. In addition, there is a problem that the diameter of the enlarged portion of the grommet is increased by an amount corresponding to the gap between the electric wires, and the grommet is enlarged.

The present invention has been made in order to solve the above-mentioned problems, and the process is relatively simple and the cost increase is small.
It is an object of the present invention to provide a waterproofing method of a wire harness that can be completely waterproof and a waterproof structure of a wire harness insertion grommet formed by the waterproofing method.

[0009]

To achieve the above object, according to the present invention, there is provided a wire harness for waterproofing between wires of a wire harness to be inserted into a mounting grommet into a panel through hole. When laying the wire group at the time of assembly, the waterproofing agent having a required viscosity is applied to the wire group of the portion to be waterproofed between the wires so as to penetrate between the wires,
Next, after inserting a resin rod into the portion where the water-stop agent has been applied, the sheet is wound and rounded into a circular cross section.
There is provided a method for waterproofing a wire harness, wherein the wire harness is passed through the grommet.

[0010] When the waterproofing agent is applied to the wired electric wire group, the electric wire groups are arranged adjacent to each other in a line, and a waterproofing agent having a required viscosity is applied to the parallel electric wire group. It is preferable to apply so as to penetrate between the electric wires. As the water stopping agent, a silicone water stopping agent having a viscosity of 1000 poise or more,
A modified ester resin, a synthetic rubber-based water stopping agent and the like are preferably used.

Further, according to the present invention, in a second aspect of the present invention, a grommet insertion portion of a wire group constituting a wire harness is filled with a waterproofing agent, and the resin rod extends in the length direction of the wire group. The wire harness insertion grommet is provided with a waterproof structure in which the outer peripheral surface of the wire group is wound in a sheet and is inserted through the grommet in this state.

As described above, when the waterproofing agent is applied to the group of wires laid on the wire harness assembly line, the waterproofing agent is applied to the surface of each wire without fail.
When applied so as to penetrate into the gaps between the electric wires, the waterproofing agent can be surely applied to the surfaces of the electric wires and between the electric wires. afterwards,
After inserting a resin rod into these electric wire groups, the resin rod is covered with a foamed sheet and rolled, so that the waterproofing agent is taken out without adhering to the operator's hand. In addition, since the sheet is wound by inserting the resin rod, the shape filled with the water-stopping agent can be maintained without bending, and the water-stopping agent can be prevented from flowing and diffusing. In this state, when the grommet is inserted into the grommet and brought into close contact with the small-diameter pipe portion, reliable waterproofing can be easily provided.

It is to be noted that at least 4 to completely cure the water blocking agent.
It took eight hours, by which time it was inserted into the grommet,
The wire harness may be shipped after the assembly of the wire harness is completed, and an external force may be applied to the grommet in which the waterproofing agent is not cured. Even in that case, since the resin rod is inserted into the wire group filled with the water blocking agent, even if a bending force is applied, the bending can be corrected by the repulsion of the resin rod, and it may be hardened in the bent state There is no.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 (A) to 1 (F) show a method of the present invention, in which a waterproof jig 11 is set on a wire harness assembling worktable 10, and as shown in FIG. After passing through a line, as shown in FIG.
000-2000 poise silicon-based waterproofing agent 5 is applied, and then, as shown in (C), after lowering the waterproofing jig 11, as shown in (D), a resin rod 6 is interposed between the electric wire groups.
And then cover with soft tape 7, then
As shown in (E), the foamed sheet 7 is rounded to have a circular cross section, and in this state, is inserted through the grommet 1 as shown in (F).

As shown in FIGS. 2 and 3, the waterproofing jig 11 includes a support shaft 12 which is attached to the assembling worktable 10 so as to be able to move up and down, and a substrate 13 fixed to the upper end of the support shaft 12.
And a pair of wire holding members 14 and 15 protruding from the substrate 13 at a required interval. The pair of wire holding members 14 and 15 are fixed on the upper surface of the substrate 13,
Wires w are inserted from the upper end openings 14b and 15b, and the elongated wires 14a and 15a for inserting the electric wires w are arranged in a line. The tip is inclined in the opening direction.

A wiring jig 11 is disposed on a wire harness assembly worktable 10 at a position where a grommet is to be attached. When holding the electric wire w with another electric wire receiving jig 20 (shown in FIG. 3) and laying, the electric wire group W is inserted between the pair of electric wire holding members 14 and 15 of the waterproofing jig 11. I do.
At the time of insertion, in the wire insertion slots 14a, 15a of the wire holding members 14 and 15, both ends of the upper end openings 14b, 15b are inclined and open. When the electric wire group W is pushed in, the electric wires w are pushed into the elongated holes 14a and 15a in a state of being aligned one by one.
That is, as shown in FIG. 1 (B), in the waterproof section X, the wires are laid in a state where they are arranged adjacent to one another in the vertical direction.

After finishing the wiring of the wire group W on the assembling worktable 10, the applicator 26 filled with the waterproofing agent 5 is used to
The waterproofing agent 5 is applied to the wire group W in the waterproof section X. The applicator 26 has a flat spatula 27a at the tip of a tube 27, and nozzles 27b at the required pitch at the tip of the spatula 27a. Therefore, when the tube 27 is pushed, the water stopping agent 5 is pushed out from the nozzle 27b through the spatula 27a. Note that the tube may be a cartridge type in which a single application amount (for example, 330 ml) is filled.

The applicator 26 has nozzles 27 at a required pitch.
Since three b are provided, as shown in FIG. 1 (B), once applied from the upper end to the lower end of the waterproof section X, the applied waterproofing agent spreads to some extent in the lateral direction.
The waterproofing agent 5 is applied to the entire waterproof section X.

At the time of the application, as shown in FIG. 4 (A), the nozzle 27b is pushed between the electric wires w, and the gap between the electric wires w is filled with the waterproofing agent 5. After one side is applied, the other side is similarly applied from the upper end to the lower end by the applicator 26. As a result, FIG.
As shown in (2), the water blocking agent 5 is applied to the entire surface of all the electric wires w and the gap between the electric wires w. At this time, since the water-stopping agent 5 to be applied has a viscosity, there is little dripping downward.

Next, as shown in FIG. 1C, the support bar 12 of the waterproof jig 11 is removed from the nut and the assembly work table 10 is removed.
Lower more. When the board 13 hits on the wiring board 10, it stops. The lowering of the substrate 13 causes the wire holding members 14, 15
Also descends, and the wire group W to which the waterproofing agent 30 has been applied is removed from the waterproof jig 11.

After detaching from the waterproofing jig 11 as described above, a small-diameter round rod-shaped resin rod 6 is inserted into the center of the wire group W to which the waterproofing agent 5 is applied in the waterproof section X. The length of the resin rod 6 is substantially the same as the length of the grommet 1. After inserting the resin rod 6, a wide rubber urethane foam sheet 7 is covered. With the foam sheet 7 covered in this way, the electric wire group is rolled into a circular cross section while preventing the waterproofing agent 5 from being attached to the operator's hand.

As described above, the foam sheet 7 is wrapped around the outer peripheral surface of the wire group W in which the water blocking agent 5 is applied and the resin rod 6 is inserted, thereby keeping the wire group W in a circular cross section.
It is possible to prevent the applied waterproofing agent 5 from being diffused and leaking, and to prevent bending of the portion.

Thereafter, as shown in FIG. 1 (F), the grommet 1 is passed through the waterproof section X, and
Attach. At this time, although the hardening of the water blocking agent 5 has not been completed yet, as shown in FIG. 5, since the wire group W passing through the grommet 1 is supported straight by the resin rod 6,
Even if an external force is applied, it is not cured in a bent state.

The method of applying the waterproofing agent 5 to the group of electric wires laid on the wire harness assembly work table 10 is not limited to the method of the above embodiment, and the method for applying the water blocking agent 5 on the assembly work table can be used. Any method may be employed as long as the waterproofing agent 5 is applied to the surfaces of the wires and the gaps between the wires in the wire group W.

[0025]

As is apparent from the above description, according to the method for waterproofing a wire harness according to the present invention, it is necessary to attach a grommet on the wire harness assembling line to perform a waterproofing process at the time of wiring. A waterproofing agent can be applied to the electric wire group at the site. That is, the waterproofing agent application step which had to be conventionally performed in a separate step can be performed on the wire harness assembly line, and the waterproofing step can be simplified and speeded up.

Even if it takes a long time to cure the water blocking agent applied to the wire group, a resin rod is inserted between the wire groups to support the wire group so that bending does not occur. The grommet can be attached without waiting, and the wire harness can be assembled and shipped.

[Brief description of the drawings]

1 (A) to 1 (F) are drawings showing a waterproofing step of the present invention.

FIG. 2 is a perspective view of a waterproof jig used in the above method.

FIG. 3 is a perspective view showing a state where the waterproofing jig is attached to a wire harness assembly work table.

4 (A) and 4 (B) are drawings showing an operation of applying a water stopping agent.

5A and 5B are cross-sectional views showing a waterproof structure of a grommet formed by the method of the present invention.

FIG. 6 is a sectional view showing a waterproof structure of a conventional grommet.

FIG. 7 is a schematic view showing a conventional grommet waterproofing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Grommet 5 Waterproof agent 6 Resin rod 7 Foam sheet 10 Assembly work table of wire harness 11 Waterproof jig 12 Support rod 13 Substrate 14, 15 Electric wire holding material 26 Coating tool w Electric wire W Electric wire group

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuhiro Kawachi 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (2)

[Claims] 1. A wire harness for waterproofing between wires of a wire harness to be inserted into a mounting grommet into a panel through hole. On the other hand, a waterproofing agent having a required viscosity is applied so as to penetrate between the wires, and then a resin rod is inserted into a portion where the waterproofing agent is applied, and then the sheet is wound and rounded into a circular cross section. A method for waterproofing a wire harness, wherein the wire harness is passed through the grommet in a state. 2. A grommet insertion portion of a wire group constituting a wire harness is filled with a waterproofing agent, and a resin rod extending in the length direction of the wire group is passed through the wire group.
The waterproof structure of the wire harness insertion grommet, wherein the outer peripheral surface of the wire group is wound in a sheet in this state and inserted into the grommet.