JPH0625972Y2 - Flexible printed circuit board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a flexible printed circuit board in which a circuit pattern is provided on the inner surface of a flexible insulating film.

[Conventional technology]

Conventionally, when a flexible printed circuit board is used for the circuit board provided with the contacts of the push switch, the circuit pattern and the contact are printed on one surface of the insulating film, and the circuit pattern is placed in the center part so that the circuit pattern is on the inside. Bend with
The flexible printed circuit board was formed by sandwiching an insulating spacer with the contact part punched out. Then, the folded film and the spacer therebetween are fixed to each other with an adhesive.

[Problems to be solved by the device]

In the case of the above-mentioned conventional technique, there is a problem that the number of steps for bonding the film and the spacer with the adhesive is relatively large and the cost is high. Furthermore, since they adhere to each other, it is difficult to align them when they are attached. In particular, since it was difficult to fix the contact of the push switch accurately with an adhesive via a spacer, there was a problem that the yield as a product was not good.

The present invention has been made in view of the above conventional technique, and an object of the present invention is to provide a flexible printed circuit board that can be easily assembled, can be accurately aligned, and can reliably improve the yield of products.

[Means for Solving the Problems]

In this invention, a flexible film having a circuit pattern and contacts formed on one surface is bent at the center, and an insulating spacer is provided between them, and a slit is formed on one of the bent pieces of the film and the spacer. Is
A flexible printed circuit board is provided with lead terminal tongues to be inserted into the slits on the other bent piece facing the slit in a bent state.

[Action]

The flexible printed circuit board of the present invention can easily align the film on which the circuit is formed with the spacer by inserting the lead terminal tongue provided on the film into the spacer and the slits of the opposing film. It was done.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show a first embodiment of the present invention, in which a circuit pattern (not shown) is formed by printing on one surface of a flexible film 1 having insulation such as polyethylene. A lead wire 2 at one end of this circuit pattern is printed on a lead terminal tongue piece 3 extending from a side edge of the film 1. In this film 1, the bent portions 1d, 1d on both sides of the long hole 1a are bent so that the circuit pattern is on the inside with the long hole 1a in the center as an axis, and each bent piece of the film 1 in the bent state. A flexible spacer 4 for insulating the facing circuit pattern is sandwiched between 1b and 1c.

Through holes 4a are formed in the spacers 4 at positions corresponding to the contacts (not shown) of the circuit pattern of the film 1, and the contacts of the bending pieces 1b and 1c facing each other can be connected. Further, a recess 4b into which the bent portion 1d of the film 1 is fitted is formed on one side edge of the spacer 4.

The bent piece 1b of the film 1 on which the lead terminal tongue piece 3 is formed is further provided with a relatively small small tongue piece 5 at the end opposite to the lead terminal tongue piece 3.
The slits 6 and 6 for passing the lead terminal tongue piece 3 and the small tongue piece 5 of the folded piece 1b in the folded state are formed at the corresponding locations on the sandwiched spacer 4 and the other bent piece 1c, respectively. Has been done.

Assembling the flexible printed circuit board of this embodiment,
The film 1 on which the circuit pattern is formed is folded around the elongated hole 1a and the bent portion 1d so that the circuit pattern is on the inside, and the spacer 4 is sandwiched between them. And
The lead terminal tongue piece 3 and the small tongue piece 5 are respectively inserted into the slit 7 of the spacer 4 and the slit 6 of the bent piece 1c so as to project to the opposite side. At this time, the bent piece 1d of the film 1 is fitted into the recess 4b of the spacer 4 to prevent the positional deviation in the longitudinal direction.

This flexible printed circuit board is attached to the back side of the operation panel of the electronic device, and the contact of the circuit is connected by pressing the portion of the spacer 4 where the through hole 4a is located from above the film 1 with a push switch. The signal is sent to the control circuit through the lead wire 2.

According to the flexible printed circuit board of this embodiment, since the film 1 and the spacer 4 are positioned by the slits 6 and 7 of the film 1 and the spacer 4 and the tongues 3 and 5, the assembling work is easy. , Accurate alignment is possible.

Next, another embodiment of the flexible printed circuit board of the present invention will be described with reference to FIGS. 4 (A), (B) and (C).

In this embodiment, the slit 6 into which the small tongue piece 5 of the film 1 is inserted is formed in a U-shape to facilitate the insertion of the small tongue piece 5. In particular, in the case of FIG. 4 (B), the opposing portions of the slit 6 are spread toward the front, so that the small tongue piece 5 can be inserted more easily, and the small tongue piece 5 can be inserted into the slit 6 as well.
It is difficult to move to the base end of. Further, in the case of FIG. 4 (C), the base end portion of the slit 6 is widened, and if the small tongue piece 5 is inserted and positioned in the narrow portion of the slit 6, it can be fixed accurately without play. Becomes

Next, still another embodiment of the flexible printed circuit board of the present invention will be described with reference to FIG.

In this embodiment, the film 1 is provided with an auxiliary tongue piece 8 in a direction orthogonal to the inserting direction of the small tongue piece 5, and a slit 9 is also formed in a portion facing the auxiliary tongue piece 8. Further, the slits are similarly provided in the spacers corresponding to the slits 9.

As a result, the film 1 and the spacer are more securely fixed, and the positional deviation between the bent pieces 1b and 1c of the film 1 can be eliminated.

The tongue piece of this invention may be welded to another portion of the film. Further, the shapes of the tongue and the slit can be appropriately selected, and any tongue that can be inserted into the slit may be used.

[Effect of device]

The flexible printed circuit board of the present invention enables the positioning of the folded pieces of the film and the folded pieces and the spacer by inserting the lead terminal tongue into the slit, which facilitates assembly.
It is possible to perform accurate positioning and surely improve the yield as a product.

Further, in the case of inspecting and repairing the electronic circuit, there is an advantage that the lead terminal can be pulled out from the slit and the circuit pattern can be rotated by 180 degrees to facilitate the operation.

Further, the lead terminal is skillfully utilized as a tongue piece to be inserted into the slit, so that accurate positioning of both the bent pieces and the spacer and insulation between the lead wire and the circuit on the other bent piece can be surely performed.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of the present invention, FIG. 2 is a partially cutaway perspective view of this embodiment, FIG. 3 is a development view of a film of this embodiment, and FIGS. 4 (A) (B) ( C) is a partial cutaway development view of the film of another embodiment of the present invention, and FIG. 5 is a partial cutaway development view of the film of yet another embodiment of the present invention. 1 ... Film, 1b, 1c ... Bending piece, 3 ... Lead terminal tongue piece, 4 ... Spacer, 5 ... Small tongue piece, 6, 7, 9 ... Slit, 8 ... Auxiliary tongue piece

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Morio Tada 3158 Shimookubo, Osawano-cho, Kamishinagawa-gun, Toyama Prefecture Hokuriku Electric Industry Co., Ltd. (56) Reference JP 62-155585 (JP, A) -84952 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A flexible film 1 having an insulating property, which has a circuit and a contact formed on one surface and is bent in the center so that the circuit is located inside, and folding pieces 1b, 1c of the bent film. A spacer 4 which is sandwiched and insulates the facing circuit and has a contact portion punched out, one bent piece 1c of this film, and slits 6 and 7 formed so as to face each other on the spacer 4 and bent. And a lead terminal tongue piece 3 provided on the other bent piece 1b at a position corresponding to the slits 6 and 7 and inserted into the slits 6 and 7 in this state.