JPH05218597A - Flexible circuit board - Google Patents

Abstract

PURPOSE:To make it possible to fold a flexible circuit board easily and in neat order by providing cut-offs in the base film and the cover film at bent spots of the extended part of the flexible circuit board, and providing marks for top folds and bottom folds showing spots to be folded. CONSTITUTION:A flexible circuit board 1 is composed of a base film, a circuit pattern, and a cover film, and is divided into a body part 2 and an extended part 3 from a planar view. A V-shaped cut-off 14 is provided at each one end of the base film 4 and the cover film 6 in the peripheral part excluding the circuit pattern 5 at the intermediate part of the extended part 3, and a circular cut-off 15 is provided at each other end. They are provided facing each other vertically to the extended direction of the extended part 3 respectively. This pair of a V-shaped cut-off 14 and a circular cut-off 15 is provided at each of five spots in the extended part 3 at intervals of a specified section. And the cut-off shapes of a pair of a V-shaped cut-off 14 and a circular cut-off 15 and an adjacent pair of a V-shaped cut-off 14a and a circular cut-off 15a are changed in turn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible circuit board mounted on electronic equipment such as a spindle motor.

[0002]

2. Description of the Related Art Some models of spindle motors employ a flexible circuit board as a means for supplying an electric current to a stator coil wound around a stator. The flexible circuit board is composed of a base film, a circuit pattern arranged on the upper surface of the base film, and a cover film covering the circuit pattern, and can be divided into a main body portion and an extending portion.

The main body has various shapes such as a circular shape, a fan shape, and a semicircular shape. The base film of the main body is attached to a predetermined position on the bracket of the spindle motor, the circuit pattern is expanded, and the land is formed at the end thereof.

The circuit film is exposed by removing the cover film on the upper surface of the land portion, and the end portion of the coil wire pulled out from the stator coil wound around the stator of the spindle motor is soldered at this land portion. It is attached.

On the other hand, an extension portion extends outward from the main body portion beyond the bracket of the spindle motor, and a connector connected to the power supply means is attached. The extending portion is narrower than the main body portion, and the circuit patterns are arranged in parallel in the center. The circuit pattern is adhered to the base film and the cover film and is completely insulated. Although there are various lengths of the extending portion, it is generally sufficient that the spindle motor is mounted on the magnetic disk drive and can be connected to the power supply means.

[0006]

By the way, some magnetic disk drive devices are considerably distant from the mounting position of the spindle motor to the power supply means. In such a case, the length of the extension part becomes extremely longer than that of the main body,
When packaging a finished spindle motor product equipped with a flexible circuit board, the extending portion was folded in a fold shape.

On the other hand, depending on the magnetic disk drive,
The mounting position of the spindle motor and the power supply means are close to each other, and after the spindle motor is mounted, the extending portion is pulled out to the outside of the magnetic disk drive and connected to the power supply means outside, and then the power supply means is connected to the magnetic disk. Some are mounted in the drive. In such a case as well, the extension portion becomes long in the process and occupies the internal space after being attached to the magnetic disk drive device. Therefore, the extension part is folded in a fold shape, extended at the time of connection, and folded at the time of mounting.

However, bending the extended portion which has been extended has various forms depending on the sensation of the operator and how to fold it, which may impair the appearance.

The present invention has been made in view of the above facts, and an object of the present invention is to provide a flexible circuit board in which the extending portion can be easily folded in a fold shape with a relatively simple structure. Is to provide.

[0010]

In order to achieve the above-mentioned object, notches are provided in a base frame and a cover frame at a bent portion that is bent in a fold shape in an extending portion of a flexible circuit board, and a mountain fold and a valley are formed. Fold marks are provided.

[0011]

[Function] Since the base frame and the cover frame at the bent portion of the extending portion of the flexible circuit board are provided with the notches, the bent portion is clearly indicated, and the marks of the mountain fold and the valley fold are provided. , If you do the bending work according to the mark, you can organize it neatly.

[0012]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of a flexible circuit board as an embodiment of the present invention, and FIG. 2 is AA 'in FIG.
FIG.

Reference numeral 1 is a flexible circuit board. The flexible circuit board 1 is composed of a base film 4, a circuit pattern 5, and a cover film 6.

The base film 4 is made of, for example, a polyimide resin and has a thickness of 25 μm. For the circuit pattern 5, a conductive metal thin film such as copper foil is used as the base film 4.
It is written by etching in a predetermined shape on the
The thickness is 35 μm or 70 μm. Like the base film 4, the cover film 6 is made of a polyimide resin and has a thickness of 25 μm like the base film. The polyimide resin is insulative, and the base film 4
Circuit pattern 5 covered with a cover film 6 and
Is completely insulated except at certain points.

The flexible circuit board 1 having the above-mentioned cross-sectional structure can be divided into a main body portion 2 and an extension portion 3 in plan view.

The outer periphery of the main body 2 is substantially circular and has a donut shape in which a substantially circular notch 9 is provided at the center. In the circuit pattern 5, four fan-shaped expansion patterns 7 each having a predetermined area are formed around the donut-shaped main body 2, and the extension patterns are drawn out from each of the four expansion patterns 7 in an elongated shape. It is connected to outlet 3. A cover film 6 having a circular notch smaller than the expansion pattern 7 is provided on the upper surface of the expansion pattern 7, and its size is the same as that of the base film 4. The circuit pattern 5 is exposed at the portion of the extended pattern 7 from which the cover film 6 has been removed, and serves as a land portion 8 as an electrical connecting means capable of conducting with the outside.

An extension 3 having a width smaller than the diameter of the main body 2 is integrally formed from one end of the main body 2. The extension portion 3 has a cross-sectional shape as shown in FIG. 2, is elongated in a plan view, and has an end portion that serves as a connector portion 11. The extension patterns pulled out from the extension pattern 7 of the main body portion 2 continue to the connector portion 11 from the central portion of the extension portion 3 while maintaining their insulating properties.

The connector portion 11 is located at the other end of the extension portion 3 with respect to the main body portion 2 and is connected to a power supply means for supplying power from the outside. Like the main body 2, the connector 11 is also slightly expanded from the extension 3 to form an expansion pattern 12 in the connector 11. Expansion pattern part 12
The cover film 6 is removed and the connector means 13 for connecting to the power supply means is mounted on the upper surface of the connector. The connector pin for connection projects from the connector means 13, and the connector pin comes into contact with the extended pattern portion 12. There is.

In the middle portion of the extension portion 3, a V-shaped notch 14 is provided at one end of the base film 4 and the cover film 6 at the outer edge portion excluding the circuit pattern 5, a circular notch 15 is provided at the other end, and the extension portion 3 is provided. Is provided so as to be perpendicular to the extension direction of the. Moreover, the pair of V-shaped cutouts 14 and the circular cutouts 15 are provided at five positions with a predetermined section of the extension portion 3 separated.
The pair of V-shaped notches 14 and the circular notches 15 and the pair of adjacent V-shaped notches 14a and the circular notches 15a are alternately provided with notches. V-shaped notch 1 in extension 3
.. and circular notches 15, 15a, .. will be described with reference to FIG.

A pair of V-shaped notches 14 and a circular notch 15 indicate bent portions in the extending portion 3, and one of the V-shaped notches 14a and the circular notch 15a adjacent to each other is formed in a mountain shape and the other is formed in the other. It shows that it is bent in a valley shape. For example, according to the example of FIG. 3, if the V-shaped notch 14 is on the right side with respect to the extension direction of the extending portion 3 and the circular notch 15 paired with it is on the left side, a mountain-shaped bend is made to form the V-shaped notch 14a. Is bent on the left side with respect to the extension direction of the extending portion 3, and if the circular notch 15a paired therewith is on the right side, a valley-shaped bending is performed.

Further, in this embodiment, the V-shaped notch is provided at the bent portion, but since the base film 4 and the cover film 6 are partially removed in the V-shaped notch, the width of the flexible circuit board 1 becomes narrow. The structure is easy to bend.
Therefore, if the circular notch that makes a pair with the V-shaped notch is also a V-shaped notch, the bending process will be easier, but since the mark of the mountain fold valley fold will be eliminated, the depth and shape of the groove of the opposite V-shaped notch will be changed. Alternatively, it is necessary to provide a means for printing the mark of the mountain fold and the valley fold on the cover film 6.

Next, the mounting of the flexible circuit board 1 having the above structure to the spindle motor will be described with reference to FIG.

The spindle motor 20 is composed of a bracket 21 fixedly mounted on a base (not shown) of a magnetic disk drive and a hub 22 on which a disk is mounted and which rotates relative to the bracket 21. There is.

The base film 4 of the main body 2 of the flexible circuit board 1 is attached to the end surface of the bracket 21. The coil wire 24 drawn out from the hole provided in the central portion of the bracket 21 penetrates the central hole 9 provided in the main body portion 2 of the flexible circuit board 1 and is led out to the cover film 6 side, and is landed on the land portion 8. It is soldered.

Although the embodiments of the flexible circuit board according to the present invention have been described above, the present invention is not limited to the embodiments and various modifications and corrections can be made.

For example, in the flexible circuit board 1 of this embodiment, a mountain fold was made when the V-shaped notch was on the left side and the circular notch was on the right side, but the V-shaped notch was on the left side and the circular notch was on the right side. If the conditions are unified such that valley folds are sometimes performed and mountain folds are performed in the opposite configuration, there is no difference from the flexible circuit board 1 of the present embodiment.

Further, the shapes of the V-shaped notch and the valley-shaped notch are not limited to those in the present embodiment, and can be freely modified. Further, it goes without saying that the shape and length of the main body 2 and the extension 3 of the flexible circuit board 1 may be freely deformable.

[0029]

In the flexible circuit board of the present invention, the V-shaped notch and the circular notch are provided by providing the V-shaped notch and the circular notch in the base frame and the cover frame at the bent portion of the extending portion of the flexible circuit board. It is possible to distinguish mountain folds and valley folds from the positional relationship of (1) and (3) and (2), where the bending points are clearly indicated, and the flexible circuit board can be folded easily and neatly.

[Brief description of drawings]

FIG. 1 is a plan view of a flexible circuit board according to the present invention.

FIG. 2 is a sectional view taken along the line A-A ′ in FIG.

FIG. 3 is a perspective view when the flexible circuit board is bent.

FIG. 4 is a perspective view when a flexible circuit board is attached to a spindle motor.

[Explanation of symbols]

 1 flexible circuit board 2 main body part 3 extension part 4 base film 5 circuit pattern 6 cover film 8 land part 14 V-shaped notch 15 circular notch

Claims (1)

[Claims] 1. A main body having a base film, a circuit pattern provided on the upper surface of the base film, and a cover film provided on the upper surface of the circuit pattern, and having a means for electrically connecting to an electronic device. A flexible circuit board that extends outwardly from the main body and connects to a power supply means, and the extension is a fold-shaped flexible circuit board. And the cover frame is provided with a notch, and a mark for a mountain fold or a valley fold is provided.