JP2558909Y2 - Flexible printing wire harness - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a flexible printed wire harness used for wiring of electric and electronic devices.

[Conventional technology]

2. Description of the Related Art Numerous electric wires are provided in electric and electronic devices to carry various information and energy. Terminals on this wire,
A system in which connectors, tubes, tapes, and the like are arranged systematically and completed as a single part in a form that is easy to attach to electrical and electronic equipment is generally called a wire harness.

In this wire harness, the number of circuits in the harness has been dramatically increased with the remarkable progress in electronics. In order to respond to the great demands of the era of multifunctional, compact, lightweight and thin electric and electronic equipment, the wiring harness is automatically assembled, lightened, space-saving, integrated with part numbers, and equipped with standby connectors. In order to meet the needs of the age of improving productivity by one-touch assembly of component units, a new flexible printed wire harness (hereinafter abbreviated as FPC wire harness) has begun to be used instead of a conventional wire harness.

FPC is an abbreviation of Flexible Printed Circuits, which is formed by printing wiring patterns of electrical and electronic circuits on an insulator such as polyester film or polyimide film.
It is characterized by being thin and bendable.

Also, the FPC wire harness was molded integrally with the plastic plate, or bonded to the plastic plate using an adhesive, or molded into a sandwich with foamed polyethylene, urethane foam, polypropylene, foamed styrene, foamed silicone, etc. It is generally used in the form.

[Problems to be solved by the invention]

When the above-mentioned conventional FPC wire harness is actually used, Joule heat is naturally generated during energization, and the temperature rises. When the outside air temperature is high, for example, when it is incorporated as part of a device that generates high heat, or when it is used in a device that generates heat under the hot summer sun in Japan or a foreign country, the ambient temperature is reduced to 70 to 80 ° C. It is not uncommon to be.

In such a case, the wiring circuit of the FPC wire harness is further heated to 10 to 20 ° C, sometimes 30 ° C by Joule heat.
Temperature may also rise, eventually reaching 90-110 ° C.

If the temperature rises in this way, problems will occur in the life of the FPC wire harness and terminal connector, and in the adhesion between the FPC wire harness and the foam molding resin. I was

This invention was made in view of the current state of the above-mentioned conventional FPC wire harness, and the purpose is to laminate a flexible heat conductive layer on at least one surface of the wire harness layer,
An object of the present invention is to provide an FPC wire harness having a heat-radiating end protruding from the end surface of the good thermal conductor layer to dissipate Joule heat due to energization of a conductive circuit and having high cooling efficiency and practical use.

[Means for solving the problem]

Therefore, in the present invention, as a means for solving the above-mentioned problem, a conductor circuit having a required wiring pattern printed thereon and a wire harness layer formed by laminating a plastic film insulator with an adhesive on both surfaces thereof, and a closely attached juxtaposition on one surface thereof A flexible heat conductive layer, a plastic protective layer provided on the outside thereof, and a plastic mold layer provided on the opposite surface are laminated, and the heat conductive layer is formed from the longitudinal end face of the laminate. The structure of the flexible printed wire harness that protrudes along the end surface to form a heat dissipation end was adopted.

The thermal conductor layer may be provided on both sides of the wire harness layer.

The material and shape of the above-mentioned thermal conductor layer include iron foil, copper wire mesh,
Aluminum foil, stainless steel wire mesh, nickel metal foam, etc. can be used to be flexible or have a thickness that can maintain flexibility, but other metals, alloys,
Compounds and the like may be any compounds as long as they have the same or higher thermal conductivity and flexibility as described above.

Further, the shape is not limited to a foil, a wire net, and a metal foam, but may be, for example, a braided body, a porous body, a woven body, a mat, a sintered metal fiber porous sheet, or a composite selected from these.

[Action]

The FPC wire harness according to the present invention configured as described above has a radiating end of a heat conductive layer, and by exposing this to the outside air, Joule heat generated due to energization escapes from the radiating end to the atmosphere and is radiated. You. Therefore, the temperature rise due to energization is considerably suppressed as compared with the conventional FPC wire harness having no thermal conductor layer.

Moreover, since the heat conductive layer is made of a material having flexibility or a range capable of maintaining flexibility, the property of a flexible wire harness is secured as a whole.

In addition, even if current is continuously supplied at a high ambient temperature for a considerably long period of time as a result of obtaining the above-mentioned heat radiation effect, the adhesive performance between the layers does not deteriorate.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

First Embodiment As shown in FIG. 1, an FPC wire harness according to this embodiment has a conductor circuit 1 on which a required wiring pattern is printed and formed, and a polyester film 3, 3 laminated on both sides thereof with an adhesive 2 on both sides thereof. The layer 4, a thermally conductive layer 5 of a flexible iron foil closely attached to one side thereof, a back panel 6 of an ABS resin provided outside thereof, and a urethane mold layer 7 provided on the opposite side to the above. The heat dissipating end 8 is formed by laminating the heat conductive layer 5 from the end face of the laminate.

The wiring harness layer 4 is formed by bonding the polyester films 3 and 3 having a thickness of 50 μm and the copper conductor circuit 1 having a thickness of 35 μm with an adhesive.

On this wire harness layer 4, a 50-micron-thick heat-resistant conductive layer 5 made of iron foil is adhered on one side, and the wire harness layer 4 with the iron foil is attached to an ABS resin back panel. 6 is integrally formed with the injection molding.

After the integral molding, the integral molded wire harness layer 4 is further integrated with the urethane mold layer 7 by sandwiching it with the back panel 6.

The rising temperature and the adhesive strength of the FPC wire harness of this example configured as described above were measured. The measurement results are as follows.

When the FPC wire harness was energized and the temperature of the conductor circuit in the center of the harness was measured when the external ambient temperature was 80 ° C.
98 ° C. After holding at 98 ° C. for 2,000 hours, the ABS resin back panel 6, the heat conductive layer 5 made of iron foil, and the urethane mold layer 7 were peeled off, leaving only the wire harness layer 4. The peeling force of the polyester film 3 was measured. When the adhesive strength was evaluated, the adhesive strength before and after holding at 98 ° C. for 2000 hours was 1.3 and 1.0 kg / cm, respectively.

Therefore, a comparative example was created from the above measurement results to evaluate the heat radiation effect and the deterioration of the adhesive performance. The configuration of the comparative example is the same as that of the above-described embodiment, except that the thermal conductor 5 of the iron foil is omitted, and the other components are laminated exactly the same.

With respect to this comparative example, the same test as described above was performed, and the rise temperature and the adhesive force were measured. The results were as follows.

Temperature after energization 108 ° C Before holding for 2000 hours Adhesive force after 1.3kg / cm before 0.2kg / cm after Next, materials other than iron foil used as the thermal conductor layer 5 of the FPC wire harness of the above-described embodiment Various types of FPC wire harnesses, each of which is suitable for use as a heat conductor having a shape that is flexible or has a thickness that can maintain flexibility, are selected, and FPC wire harnesses integrally formed with the wire harness layer 4 in place of the iron foil are described in Example 2. 5 were prepared in the same manner as in Example 1 described above.

When the same measurements as in Example 1 were performed for Examples 2 to 5, the results shown in Table 2 were obtained.

From the above measurement results, it can be seen that the temperature rise of each of the FPC wire harnesses after energizing at about 10 ° C. is lower than that in the case where a good thermal conductor is not used.

Also, there is a clear difference in the evaluation of the adhesive strength,
According to another practical test, a result that the adhesive force was not practically usable when the adhesive force was 0.5 kg / cm or less was obtained, but also in this respect, the adhesive force was sufficiently maintained, and it can be seen that practical use was possible.

And, needless to say, flexibility is maintained as a whole.

Second Embodiment FIG. 2 is a perspective view schematically showing the configuration of another embodiment of the FPC wire harness according to the present invention.

The FPC wire harness of this embodiment is different from that of FIG. 1 only in that a thermally conductive layer 5 is further added between the wire harness layer 4 and the urethane mold layer 7.

As in the first embodiment, the measurement results of the temperature rise after energization and the adhesive force when various materials and shapes are used as the thermal conductor are omitted, but the thermal conductor layer 5 having only one thermal conductor layer 5 is omitted. It will be apparent that the heat radiation effect and the deterioration of the adhesive performance are further improved as compared with the embodiment.

〔effect〕

As described in detail above, the FPC wire harness according to the present invention is provided with a flexible heat conductive layer in close contact with the wire harness layer, and a heat radiation end in which the heat conductive layer protrudes from the end surface of the laminate. Therefore, by exposing this heat radiation end to the outside air, Joule heat generated by energization escapes from the heat radiation end to the atmosphere, and the rising temperature of the FPC wire harness can be considerably suppressed compared to the case where no good heat conductive layer is used, and Adhesion performance after holding at the temperature rise time is remarkably improved, and it can be put to practical use while maintaining flexibility as a whole.
There is an advantage that an FPC wire harness can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a first embodiment of an FPC wire harness according to the present invention, and FIG. 2 is a perspective view showing a schematic configuration of a second embodiment. DESCRIPTION OF SYMBOLS 1 ... Conductor circuit, 2 ... Adhesive, 3 ... Polyester film, 4 ... Wire harness layer, 5 ... Heat conductive layer,
6 ... Back panel, 7 ... Urethane mold layer, 8 ...
... radiation end.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-49-100579 (JP, A) JP-A-49-135179 (JP, A) JP-A-62-281391 (JP, A) 158764 (JP, U) Japanese Utility Model Showa 62-140760 (JP, U) Japanese Utility Model Application Hei 4-65474 (JP, U)

Claims (2)

(57) [Scope of request for utility model registration] 1. A conductive circuit on which a required wiring pattern is formed by printing, a wire harness layer formed by laminating a plastic film insulator with an adhesive on both sides thereof, and a flexible heat conductive layer closely attached to one side thereof. And a plastic protective layer provided on the outer side thereof and a plastic mold layer provided on the opposite side to the above, and the heat-radiating end is formed by protruding the heat conductive layer from the longitudinal end face of the laminate along the end face. A flexible printing wire harness, characterized by forming: 2. The flexible printed wire harness according to claim 1, wherein said heat conductive layer is provided on both sides of said wire harness layer.