JPH05327136A - Flexible board - Google Patents

Abstract

PURPOSE:To decrease the number of parts and the manhour for assembling, and reduce the manufacturing cost by making boards common. CONSTITUTION:A flexible board 10 constituting the contact part of a key board unit is constituted of the following; a board part 11 wherein fixed contacts 6 of non-conduction which are closed at the time of key-pressing, and a bundle line part 12 which is formed in a unified body with the board part 11 and constitutes wirings 13 connecting the board 11 with other boards. The bundle part 12 is formed in a hair-pin type, and parts 14 like sewing holes for cutting- off which can be easily cut by hand are formed on boundaries. A part or the whole of the part 14 is cut and the budle line part is spread. Thus the boards are made common by changing the length of the budle line part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible substrate used for wiring an electronic circuit, and more particularly to a flexible substrate having a substrate portion and a bundle portion integrally formed.

[0002]

2. Description of the Related Art Generally, for example, a keyboard unit of an electronic keyboard instrument is often used in common when the number of keys is the same even if the models are different. Therefore, the keyboard circuit board is common, but the length of the bundled line connecting this board and another board may differ depending on the model. In such a case, conventionally, it has been usual to properly use the bundled wire for each model.

FIG. 4 is a side view showing an example of a keyboard unit portion of a conventional electronic keyboard instrument, and FIG. 5 is a rear view thereof, and an actuator 1a provided under a key 1 consisting of a large number of white keys and black keys. However, the normally open fixed contact formed on the keyboard circuit board 4 on the keyboard frame 3 is opened and closed via the dome-shaped contact rubber member 2.

This keyboard circuit board 4 is formed by photo-etching and silk-wiring wiring made of a conductor such as copper foil on an insulating substrate such as a paper-based phenolic resin laminated board or a laminated board impregnated with epoxy resin using glass fiber as a base material. It is formed by screen printing, plating, or the like, and the length of the keyboard bundle wire 5 made up of a large number of ribbon wires connected to the rear end is changed for each model.

[0005]

However, in such a conventional keyboard circuit board, the board portion and the bundled wire portion are separate parts, and bundled wires having different lengths for each model are provided. Since it has to be prepared, there is a problem that the number of parts increases, the number of assembling steps and the stock managing steps increase, and the cost becomes high. The present invention has been made in view of the above points, and it is an object of the present invention to reduce the number of parts to reduce the number of assembling steps and the number of stock management steps, and to reduce the production cost by sharing a board.

[0006]

In order to achieve the above-mentioned object, the present invention is a flexible board in which a board portion and a bundled wire portion are integrally formed, and the bundled wire portion is provided in a closely deployable manner. And a flexible substrate.

[0007]

The flexible substrate according to the present invention is constructed as described above, and when a part or all of the closely bundled wire portions are developed, the length of the light bundled wire portion can be freely set as required. be able to. Therefore, when the circuit boards are common and only the lengths of the bundled portions are different, the common flexible board can be used for all models.

[0008]

Embodiments of the present invention will be specifically described below with reference to the drawings. The portions corresponding to those in FIGS. 4 and 5 are designated by the same reference numerals and the description thereof will be omitted. 1 is an enlarged plan view showing the line width of an embodiment of the present invention, and FIG. 2 is a side view showing a keyboard unit portion of an electronic keyboard instrument embodying the present invention.

In FIG. 2, an actuator 1a is projectingly provided below a key 1 composed of a large number of white keys and black keys, and a flexible substrate 10 correspondingly provided on a keyboard frame 3 is provided.
The non-conducting fixed contact 6 is formed on the substrate portion 11. A well-known contact rubber member 2 integrally formed of an elastic material such as rubber is placed on a substrate portion 11, and a movable contact 7 is provided on the lower surface of a columnar portion that is vertically hung inside the actuator. By elastically deforming the rubber member 2, the movable contact 7 is pressed against the fixed contact 6 to close the fixed contact 6.

This flexible substrate 10 is a polyester film on which a pattern of copper (Cu) or silver (Ag) is applied and resist is formed thereon. For example, as shown in FIG. 1, a substrate on which fixed contacts 6 are formed. Portion 11 and a bundled wire portion 12 for connecting this conductive pattern to another substrate (not shown)
Consists of. The fixed contact 6 is carbon-treated on the metal pattern. It should be noted that although the above resist functions without using the resist, the durability can be improved by removing the fixed contact 6.

The substrate portion 11 forms a plurality (five in the figure) of fixed contacts 6, and the wirings 13 from these fixed contacts 6 are arranged in parallel on the bundled portion 12 at a predetermined pitch in a hairpin shape. A cuttable portion 14 that is closely formed and that can be easily cut by hand, such as a perforation or a thin portion, is provided at the boundary portion.
The bundled line portion 13 formed closely by cutting 4 is shown in FIG.
As shown in FIG.

Since this embodiment has the above-mentioned structure, after the board portion 11 of the flexible board 10 is arranged at a predetermined position on the keyboard frame 3, the bundle of wires is formed as shown in FIG. The cuttable portion 14 of the portion 12 is cut from the tip end side to be developed, and when the required length is reached, the cutting of the cutable portion 14 is stopped and the bundled wire portion 12 on the substrate portion 11 side is left uncut. Then, the tip end portion 12a of the bundled wire portion 12 is connected to another connector on the board side to be connected.

As described above, since the length of the bundled wire portion 12 can be freely changed by unfolding only the necessary portion of the bundled wire portion 12, all of the disconnectable portions 14 are cut and developed in advance in FIG. In the state shown in (b), if the length of the bundled part is adjusted to the model with the maximum connection distance, one flexible board can be used for multiple models or different key ranges of the same model. Can be commonly used.

Further, since only the necessary portion of the bundled wire portion 12 is developed and the unnecessary portion remains integral with the board portion 11, there is no fear that the extra bundled wire portion will interfere with the mounting and the board portion. By integrating the bundling portion with each other, the number of parts is reduced and the man-hours for assembling the both are also reduced to improve the productivity.

In the above-mentioned embodiment, the bundled wire portion 12 is formed in a hairpin shape, but the shape is not limited to this, and any shape can be used as long as it can be closely arranged so as to be deployable such as a spiral shape. It doesn't matter.

In the above embodiment, the present invention is applied to the keyboard circuit board of the electronic keyboard instrument, but the present invention can be applied to any other flexible board without any trouble.

[0017]

As described above, in the flexible board according to the present invention, the board portion and the bundled wire portion are integrally formed, and the bundled wire portion is provided so as to be expandable, so that the bundled wire portion It is possible to freely change the length by expanding a part or the whole.

Therefore, when the circuit of the board portion is common and only the length of the bundled portion is different, the common flexible board can be used for all models or different switch areas of the same model. In addition, since the board part and the bundle part are integrated, the number of parts and the assembly man-hours associated therewith are reduced, and it is possible to reduce the production cost in combination with the reduction of management man-hours due to common use. Become.

[Brief description of drawings]

FIG. 1 is a plan view showing an enlarged line width of an embodiment of the present invention.

FIG. 2 is a side view showing a cross section of a part of the keyboard unit of the electronic keyboard instrument embodying the present invention.

FIG. 3 is an explanatory view showing a developed state of the bundle of wire portions.

FIG. 4 is a side view showing an example of a keyboard unit section of a conventional electronic keyboard instrument.

FIG. 5 is a rear view of the same.

[Explanation of symbols]

1 ... Key, 2 ... Contact rubber member, 3 ... Keyboard frame, 6 ...
Fixed contact, 7 ... Movable contact part, 10 ... Flexible substrate,
11 ... Board part, 12 ... Bundled part, 13 ... Wiring, 14 ... Breakable part

Claims (1)

[Claims] 1. A flexible substrate in which a substrate portion and a bundled wire portion are integrally formed, wherein the bundled wire portion is closely arranged so as to be expandable.