JPH0419934Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention [Industrial Application Field] The present invention relates to a waterproof structure for a branch part in an automobile wire harness.

[Conventional technology and problems]

As shown in Fig. 6, the wire harness is constructed by connecting a main line _W0 , which is made by wrapping a large number of electric wires a together with tape, to a plurality of branch lines _W1 corresponding to the arrangement of on-vehicle electrical components.
It has a structure derived from .

The middle part of the main line and the branch line is straight, making it relatively easy to wrap the tape and there is little risk of water infiltration. On the other hand, the branch part T has a complicated shape, is troublesome to work, and tends to be inconsistent, and has problems such as water infiltration through the gap c of the tape b.

The purpose of the present invention is to provide a waterproof structure for a wire harness branch that is easy to work, is free from variations due to individual differences, and can provide a reliable waterproof seal.

Structure of the invention [Means for solving the problems] As shown in Figures 1 to 4, the waterproof structure of the wire harness branch of the invention is made by wrapping a sheet of elastic material such as synthetic rubber. A grommet A having a wire protection tube 2 is formed in the center of the plate 1,
While extrapolating the wire protection tube 2 of this grommet A to the branch wire W ₁ at the wire harness branch,
The winding plate 1 is wound around the outer periphery of the main line _W0 , both ends are overlapped, and a tape winding 3 is applied from above.

The dimensions of the grommet A, that is, the size of the sheet-like winding plate 1 and the length and diameter of the wire protection tube 2 are prepared in advance in various sizes depending on the type of wire harness W.

The width (or length) L of the winding plate 1 is set so that when it is wound around the main wire W ₀ of the wire harness W in a sushi roll shape, an overlapping portion 1' is formed. Further, in order to increase the contact area during wrapping and ensure waterproofness, it is preferable that the winding plate 1 is provided with corrugated plate-like irregularities 1a on both the front and back sides, as shown in Fig. 5. .

It is desirable that reinforcing ribs 2a be provided around the wire protection tube 2 in order to prevent tearing at the tip thereof.

[Effect]

According to the present invention, when assembling the wire harness W, the diameter of the wire protection tube 2 of the grommet A is expanded using a diameter enlarging jig (not shown), the branch wire W ₁ is inserted through the wire protection tube 2, and the winding plate 1 is Pull it to the branch point.

Next, by wrapping both sides of the winding plate 1 around the main line W ₀ , overlapping both ends, and then wrapping the tape 3 over it and fixing it, it can be easily and reliably wrapped in the same way as wrapping the tape around the main line W ₀ on a straight line. Able to perform work. At the same time, the tip of the wire protection tube 2 is also wrapped with tape.

As a result, there is no gap c (Fig. 6) in the wire harness branch due to tape wrapping as in the past, and there is no variation among operators, and the wrapping plate 1 and wire protection tube 2 are made of synthetic rubber or natural rubber. Because it adheres closely to the electric wire due to its viscoelasticity, a reliable waterproof sealing effect can be obtained.

Effects of the invention As explained above, the waterproof structure of the wire harness branch of the invention does not vary depending on the operator, has good workability, provides a reliable waterproof sealing effect, and eliminates the risk of water intrusion. You can get a wire harness with very stable quality.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a grommet according to an embodiment of the present invention, and FIG. 2 is a perspective view of essential parts showing an embodiment of the waterproof structure of a wire harness branch of the present invention.
Figure 3 is a cross-sectional view of the wire protection tube part in Figure 2;
The drawings are an end view of the main line portion of FIG. 3, FIG. 5 is a perspective view of a grommet according to another embodiment of the present invention, and FIG. 6 is an explanatory diagram of a conventional example. A... Grommet, W... Wire harness,
W ₀ ... Main line, W ₁ ... Branch line, 1... Winding plate, 2
...Wire protection tube, 3...Tape (roll).

Claims (1)

[Claims for Utility Model Registration] (1) A grommet A having a wire protection tube 2 in the center of a sheet-like winding plate 1 is formed of an elastic material such as synthetic rubber, and the wire protection tube 2 of this grommet A is The branch wire at the wire harness branch
A waterproof structure for a branch part of a wire harness characterized by extrapolating W ₁ , wrapping a winding plate 1 around the outer periphery of the main wire W ₀ , overlapping both ends, and applying tape wrapping 3 from above. (2) The waterproof structure of a wire harness branch part according to claim 1 of the utility model registration, which is implemented using a grommet in which corrugated plate-like irregularities 1a are provided on both the front and back sides of the winding plate 1.