JPH0927221A - Water-proof binding method for wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To markedly reduce binding work time, and reduce material cost. SOLUTION: Plural wires 1 and a nonconductive sealing material 4 comprising thermoplastic base material and conductive magnetic material are fitted into a member comprising material having pressure restoration force, and then the magnetic material in the sealing material 4 is induction-heated in an AC magnetic field. The base material is thus dissolved by generated heat for binding the wires 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof binding method for electric wires for binding a plurality of electric wires, and more particularly to a waterproof binding method for electric wires capable of ensuring sufficient waterproof performance at a binding portion of the electric wires. is there.

[0002]

2. Description of the Related Art As a waterproof binding method for a plurality of electric wires, for example, USP. There is one described in 5378897. In such a waterproof binding method, in the heat-shrinkable tube, a plurality of electric wires and a non-conductive encapsulant formed by mixing magnetic powder with a base material as a thermoplastic adhesive are positioned, The tube is pre-heat-shrinked, and then a high frequency is applied to the sealing material to inductively heat the magnetic body in an alternating magnetic field, and the heat generation melts the base material to bind a plurality of electric wires. In such a waterproof binding method, since the base material of the sealing material penetrates between the plurality of electric wires, the waterproof performance at the binding portion of the electric wires is improved.

Conventionally, a plurality of electric wires, which are passed through holes of a dashboard partitioning an engine room and a vehicle compartment of an automobile, have the above-mentioned structure in order to prevent water from entering between the electric wires. After being bound with a sealing material, the bound portion is attached to a hole or the like of the dashboard by a grommet. FIG. 6 is a diagram for explaining a procedure of a conventional waterproof binding method for binding such electric wires for an automobile.

First, as shown in FIG. 6 (a), a plurality of electric wires 1 to be bound are put together and passed through a heat-shrinkable tube 2 as shown in FIG. 6 (b). Reference numeral 3 is a connector attached to the end of the electric wire 1. After that, as shown in FIG. 3C, a non-conductive sealing material 4 made by mixing magnetic powder with a base material serving as a thermoplastic adhesive is attached to the planned binding portions of the plurality of electric wires 1. From the above, the tube 2 is displaced and positioned to the planned binding portion of the electric wires 1. Then, hot air or the like is applied to the tube 2 to pre-heat-shrink it as shown in FIG. 1D, and the outer periphery of the planned binding portion of the plurality of electric wires 1 is restrained. Then, a high frequency is applied to the sealing material 4 to inductively heat the magnetic powder in the alternating magnetic field, and at the same time, the tube 2 is fully thermally contracted, and the heat is generated to melt the base material and waterproofly bind the plurality of electric wires 1 ( The same figure (e)). Sealing material 4
The base material dissolves and permeates between the plurality of electric wires 1 to seal and waterproof the electric wires 1. After that, the grommet 5 is attached to the outer peripheral portion of the tube 2 as shown in FIG. 6F, and then the tape 6 is wound between the tube 2 and the grommet 5 as shown in FIG. Seal. An annular groove (not shown) is formed on the outer peripheral portion of the grommet 5, and the annular groove is fitted to a peripheral portion of a hole of a dashboard of an automobile or the like.

[0005]

However, in the above-mentioned conventional waterproof bundling method, the sealing material 4 is induction-heated after the tube 2 is positioned at the planned binding portion of the electric wire 1 and its preliminary heat shrinkage is performed. Therefore, there was a lot of waiting time from the attachment of the sealing material 4 to the induction heating of the sealing material 4. Therefore, there is a problem that it takes a long time to bind the electric wires 1 and the material cost increases because the tube 2 is required.

It is an object of the present invention to provide a waterproof binding method for electric wires which can significantly reduce the binding time and material costs.

[0007]

The waterproof electric wire binding method of the present invention is a waterproof electric wire binding method for binding a plurality of electric wires, wherein a member made of a material having a pressure restoring force is used and After press-fitting the plurality of electric wires and a sealing material formed by mixing a magnetic material into a thermoplastic base material, the magnetic material of the sealing material is induction-heated, and the heat generation melts the base material. The plurality of electric wires are waterproofly bound.

According to the method for waterproof binding of electric wires of the present invention, a plurality of electric wires and a non-conductive material obtained by mixing a magnetic material with a thermoplastic substrate are provided inside a member made of a material having a pressure restoring force. After press-fitting with the sealing material, the magnetic body of the sealing material is induction-heated in an alternating magnetic field, and the heat is used to melt the base material to bind a plurality of electric wires.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. The same parts as those in the conventional example described above are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 1 is a view for explaining the procedure of a waterproof binding method for electric wires 1 according to this embodiment. First, FIG.
After assembling a plurality of electric wires 1 to be bundled as shown in (a), as shown in (b) of the figure, a sealing material 4, that is, a base as a thermoplastic adhesive is provided at a planned binding portion of the plurality of electric wires 1. A non-conductive encapsulating material 4 formed by mixing a magnetic material with the material is attached.
The base material of the sealing material 4 is a non-magnetic non-conductive material,
A specific example thereof will be described later. In addition, the sealing material 4 of this example
Is a block formed in a comb shape as shown in FIG. 2, and the planned binding portion of the electric wire 1 is inserted and held in the plurality of groove portions 4A. Then, all the electric wires 1 to be bound are held by a plurality of sealing materials 4 as shown in FIG.

Thereafter, as shown in FIG. 1 (c), an elastic grommet 7 made of heat-resistant rubber is fitted to the outer periphery of the binding planned portion of the electric wire 1 as a member made of a material having a pressure restoring force,
The elastic contraction force of the cylindrical body portion 7A of the grommet 7 pressurizes and restrains the outer periphery of the planned binding portion of the electric wire 1 as shown in FIG. Then, in the present example, a high frequency is applied to the sealing material 4 from the outside of the grommet 7 to inductively heat the magnetic body in an alternating magnetic field, and the heat generated thereby melts the base material, and at the same time, the body of the grommet 7 is melted. Due to the elastic contraction force of the portion 7A, the melted base material is pressed and poured between the electric wires 1 to bind the plurality of electric wires 1 (FIG. 1 (d)). Grommet 7
As a molding material of, chloroprene rubber, EPDM (ethylene-propylene-diene terpolymer) rubber, isoprene rubber, silicone rubber, or the like can be used.

In this example, as shown in FIG. 3, the portion of the electric wire 1 to be bound is positioned in the alternating magnetic field generated by the coil 8. Examples of the sealing material 4 include a base material of an adhesive material made of a thermoplastic polymer such as polyethylene, polyamide, ethylene vinyl acetate, or a mixture thereof, and a magnetic material such as nickel, an alloy of nickel and aluminum, or ferrite. It is possible to use a dispersion of various ferromagnetic materials, and the loss of the eddy current and hysteresis of the ferromagnetic material generated in the alternating magnetic field
The ferromagnetic material is self-heated to the Curie point, and the heat causes the base material of the sealing material 4 to melt. The sealing material 4 preferably contains 0.1% to 50% of a magnetic material.

The melted base material of the sealing material 4 permeates between the electric wires 1 as shown in FIG.
Seal the space between them to make them waterproof. The body portion 7A of the grommet 7 is
The elastic contracting force promotes the penetration of the base material of the sealing material 4 into the space between the electric wires 1 and restores the cylindrical shape in cross section as shown in FIG. 4 to regulate the binding portion of the electric wire 1 to have a circular cross section.

Thereafter, as shown in FIG. 1 (e), the tape 6 is wrapped around the outer periphery of the boundary between the body portion 7A of the grommet 7 and the electric wire 1 to ensure the sealing property of these boundaries.

FIG. 5 shows an example of the structure of the grommet 7 attached to the hole 10A of the dashboard 10 of the automobile,
An annular groove 7B is formed on the outer periphery of the hole 10B.
The groove 7B is elastically fitted to the inner peripheral edge of A.

[0016]

As described above, the waterproof binding method for electric wires according to the present invention uses a member made of a material having a pressure restoring force, and a plurality of electric wires and a thermoplastic base material inside the member. After press-fitting a non-conductive encapsulant made by mixing an electrically conductive magnetic substance with the above, the magnetic substance of the encapsulant is induction-heated in an AC magnetic field, and the heat generated melts the base material As compared with the conventional waterproof bundling method of bundling a plurality of electric wires in a tube in advance, since the tube is unnecessary, the material cost can be reduced to about ⅔ as well. , The waiting time from the heat shrinkage of the tube to the induction heating of the sealing material is eliminated, and the labor of installing the tube is eliminated, so the working time is 1/3.
It can be shortened significantly.

Further, since the restoring force of the member made of a material having a pressure restoring force restrains the planned binding portion of the plurality of electric wires, when the sealing material is melted by induction heating,
It can be pressurized and permeated between multiple wires to seal them sufficiently for waterproofing, and the shape of the binding part of the wires is restricted to a circular cross section according to the internal cross-sectional shape of the member. can do.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a procedure of a waterproof binding method for electric wires according to an embodiment of the present invention.

2 is an enlarged cross-sectional view of a sealing material used in the waterproof binding method of FIG.

FIG. 3 is an enlarged cross-sectional view for explaining a state before induction heating of the sealing material after the grommet of FIG. 1 is attached.

FIG. 4 is an enlarged cross-sectional view for explaining a state of the sealing material of FIG. 1 after induction heating.

FIG. 5 is a side view for explaining an example of a mounting form of the grommet shown in FIG.

FIG. 6 is an explanatory diagram of a procedure of a conventional waterproof binding method for electric wires.

[Explanation of symbols] 1 electric wire 4 sealing material 7 grommet (member) 6 tape

Claims (7)

[Claims] 1. A waterproof electric wire binding method for binding a plurality of electric wires, wherein a member made of a material having a pressure restoring force is used, and the plurality of electric wires and a thermoplastic base material are magnetized inside the member. After press-fitting a sealing material formed by mixing the bodies, the magnetic material of the sealing material is induction-heated, and the heat is used to melt the base material to waterproofly bind the plurality of electric wires. How to tie wires together for waterproofing. 2. When the base material of the sealing material is dissolved,
The waterproof wire binding method according to claim 1, wherein the base material of the encapsulant is permeated between the plurality of electric wires by utilizing the restoring force of the member. 3. A comb-shaped sealing material having a plurality of grooves formed therein is used as the sealing material, and the plurality of electric wires are held in the plurality of grooves of the comb-shaped sealing material. The waterproof binding method for electric wires according to claim 1 or 2, wherein the comb-shaped sealing material is press-fitted inside the member. 4. The method of waterproof binding of electric wires according to claim 1, wherein the member is made of an elastic material. 5. The elastic material of the member is selected from any one of chloroprene rubber, EPDM rubber, isoprene rubber, and silicone rubber.
The method for waterproof binding of electric wires described in. 6. The encapsulating material, wherein the base material is selected from polyethylene, polyamide, ethylene vinyl acetate, or a mixture thereof, and the magnetic material is nickel, an alloy of nickel and aluminum, or ferrite. 6. The waterproof electric wire binding method according to any one of claims 1 to 5, wherein the waterproof electric wire binding method is selected from the following. 7. The tape is wound around the outer periphery of the boundary between the member and the plurality of electric wires after the base material of the sealing material is melted to bind the plurality of electric wires. 7. The waterproof binding method for electric wires according to any one of 1 to 6.