JPH11195855A - Supporting structure of flexible board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent occurrence of failure such as breakage and disconnection caused by excessive deformation of a flexible board by providing a deformation preventive member inside a bending part of the flexible board wherein one end part is connected to an electric component and bent into U-shape and then the other end part is connected to a main board. SOLUTION: A flexible board 13 for electrically connecting a main board 11 to a display device 12 is, in order to be drawn around toward the main board 11 while detouring between the press-fitting point to a land part 14a and above an LCD display part 15, folded back to the main board 11 side with a U-shape part 13c next to a short upper side straight part 13b continuous from an LCD connection part 13a, so that a lower side straight part 13d faces the main board 11 side through a lower part of the display device 12. An LCD protective frame 16 has a pair of extension leg part 16b protruded, with a deformation preventive member 17 extended from its end part. A flexible board supporting plate 17b of rigid material supports the flexible board 13 from inside for limiting its deformation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a support structure for a flexible substrate (FPC substrate).

[0002]

2. Description of the Related Art A flexible substrate can be arranged in a narrow space or a complicated shape portion in an electric device by forming a shape such as a bent portion.
It is widely used for electrical connection between main boards and electrical components. However, when an external force is applied to the bent portion of the flexible substrate, it is excessively deformed, and there is a possibility that the connection between the connection portion of the flexible substrate and the electric component is cut off or the pattern inside the substrate is disconnected.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has a simple structure for supporting a flexible substrate capable of preventing problems such as breakage and disconnection caused by excessive deformation of the flexible substrate. It is intended to be provided in a configuration.

[0004]

SUMMARY OF THE INVENTION A support structure for a flexible substrate according to the present invention comprises a flexible substrate having one end connected to an electric component, bent in a U-shape, and the other end connected to a main substrate. A deformation preventing member is provided inside the bent portion of the substrate. With this deformation preventing member, excessive deformation of the flexible substrate can be prevented.

[0005] The deformation preventing member is desirably made of a rigid material. Further, it is desirable that the deformation preventing member is formed integrally with the electric component. Preferably, the deformation preventing member has a curved surface corresponding to the inner peripheral surface of the bent portion of the flexible substrate.

In a state where no external force acts on the flexible substrate, the curved surface portion of the deformation preventing member may be in non-contact with or in contact with the inner peripheral surface of the bent portion of the flexible substrate. In the non-contact mode, the length between the one end connected to the electric component and the U-shaped bent portion of the flexible substrate can be increased to increase the allowable amount of elastic deformation. That is, a certain deformation of the flexible substrate is allowed, and the deformation preventing member prevents an excessive deformation that may cause peeling at a connection portion with the electric component or disconnection in the substrate. In the aspect in which the curved surface portion of the deformation preventing member contacts and supports the inner peripheral surface of the bent portion of the flexible substrate, it is possible to minimize the deformation of the flexible substrate when an external force is applied.

[0007] The electrical components connected to the flexible substrate are:
It is preferable to use a liquid crystal display. At this time, the liquid crystal display preferably has a frame for holding the liquid crystal display therebetween, and the deformation preventing member is preferably formed integrally with the frame.

[0008]

FIG. 1 shows a main board 11 provided in an electric apparatus and a display device 12. As shown in FIG. 2, in the display device 12, the LCD substrate 14 is held by an LCD holding frame 16. The LCD substrate 14 has an LCD display unit 15 formed on the surface, and the land unit 1
The display mode on the display surface can be changed by changing the applied voltage in accordance with the electric signal input to 4a. The LCD holding frame 16 which is thinner than the LCD substrate 14 has an opening 16a for exposing the LCD display unit 15, and the liquid crystal display is externally connected to the electric device through the LCD display unit 15 exposed from the opening 16a. Can be observed from

The display signal of the display device 12 is
1 is generated. In order to transmit a signal from the main substrate 11 to the display device 12, the main substrate 11 and the display device 12
Are electrically connected by a flexible substrate 13. The flexible substrate 13 has an LCD connection part 13a at one end thereof thermocompression-bonded to a land part 14a of the LCD substrate 14, and a main board connection part 13e at the other end.
Soldered. L from the crimping position with the land 14a
The flexible board 13 is connected to the LCD connection section 13a in order to route around the main board 11 while avoiding the CD display section 15.
After the short upper straight portion 13b continuous from the U-shaped portion 1,
3c, it is folded back to the main plate 11 side, and the lower straight portion 13d is formed so as to pass through the lower part of the display device 12 and head toward the main substrate 11 side.

The LCD holding frame 16 has an LCD connection portion 13a.
A pair of extended leg portions 16b are projected from both sides of the crimped portion of the land portion 14a. A pair of extension legs 16b
Is extended in a direction parallel to the surface of the LCD display section 15 and then bent at a substantially right angle to the LCD substrate 14 side, so that LC
It is attached to the side surface of the D substrate 14.

A deformation preventing member 17 further extends from an end of the extension leg 16b of the LCD holding frame 16.
The deformation preventing member 17 is connected to the extension leg 16b by an LCD.
A pair of extending portions 1 extending in a direction substantially parallel to the plate surface of the substrate 14
7a, and a flexible substrate support plate 17b extending in a direction substantially perpendicular to the extending direction of the extending portion 17a and connecting the pair of extending portions 17a. Deformation prevention member 17
Is formed of a rigid material such as metal. In the present embodiment, the LCD holding frame 16 and the deformation preventing member 17 are integrally formed from a metal material.

The pair of extending portions 17a are on the extension of the extension legs 16b arranged on both sides of the flexible substrate 13, and therefore do not overlap with the flexible substrate 13. on the other hand,
The flexible substrate support plate 17b includes an upper linear portion 13b and a lower linear portion 13d of the flexible substrate 13 in the laminating direction (up and down direction in FIG.
And is formed to be long in a direction substantially perpendicular to the extension direction of the flexible substrate 13, so that the flexible substrate 13 can be supported from inside. As shown in FIG. 2, the distal end of the flexible substrate support plate 17b is formed in a U-shape corresponding to the inner peripheral surface of the U-shaped portion 13c.
3 is formed to be shorter than the length of the upper straight portion 13b, so that the flexible substrate support plate 17b has a U-shaped portion 13c.
Not in contact with the inner surface of

In the above structure, the flexible substrate 1
It is assumed that an external force indicated by an arrow F in FIG.
Due to this external force, the flexible substrate 13 is deformed by a certain amount and comes into contact with the flexible substrate support plate 17b. Then, the flexible substrate support plate 17b made of a rigid material supports the flexible substrate 13 from inside, and restricts its deformation.

The flexible substrate 13 is connected to the LCD connection section 1.
The longer the length from 3a (the crimped portion) to the U-shaped portion 13c (that is, the upper straight portion 13b), the greater the allowable amount of deformation, and the less easily the crimped portion with the LCD substrate 14 is peeled off. In the present embodiment, since the upper straight portion 13b is formed to be long, the allowable deformation amount before peeling of the crimped portion or internal disconnection occurs is large. By providing the deformation preventing member 17 inside the U-shaped portion 13c, deformation of the flexible substrate 13 exceeding an allowable amount can be prevented, and peeling or disconnection of a crimped portion can be prevented. Since the tip of the flexible substrate support plate 17b is formed in a U-shape, it does not interfere when it comes into contact with the flexible substrate 13.

FIG. 3 shows a different embodiment of the present invention. In the figure, members corresponding to those in FIGS. 1 and 2 are distinguished by adding 1 to the beginning of the reference numerals, but the same parts as those in the previous embodiment are not particularly described. In this embodiment, the upper straight portion 113b of the flexible substrate 113 is short, and the flexible substrate support plate 117b of the deformation preventing member 117 made of a rigid material contacts and supports the inner surface side of the U-shaped portion 113c of the flexible substrate 113. . The distal end shape of the flexible substrate support plate 117b is formed in a U-shape so as to contact along the inner surface of the U-shaped portion 113c. In this structure, the upper straight portion 11
Although 3b is short, the allowable deformation amount is small, but the external force indicated by the arrow F in FIG. 3 is applied to the flexible substrate 113 because the flexible substrate support plate 117b supports the flexible substrate 113 even when no external force is applied. At this time, the deformation of the flexible substrate 113 is minimized.

For comparison with the embodiment to which the present invention is applied, FIGS. 4 and 5 show examples in which a support member similar to the deformation preventing members 17 and 117 is not provided. A main board 21 and a display device 22 are separately provided in the electric device, and are connected to a flexible board 23. As in the previous embodiment, the flexible substrate 23 is
LCD connection part 23a thermocompression-bonded to LCD substrate 24
And an upper straight portion 23b continuous with the LCD connection portion 23a.
And a U-shaped portion 23c folded back to the main board 21 side
A lower straight portion 23d passing under the display device 22; and a main board connecting portion 23e soldered to the main board 21.
It is composed of

LCD for holding LCD substrate 24 from above
The holding frame 26 is provided with a pair of extension legs 26b located on both sides of the LCD connection portion 23a. However, a member for supporting the flexible substrate 23 is not provided beyond the extension leg 26b.

Here, an arrow F is shown near the U-shaped portion 23c in FIG.
When an external force is applied, the U-shaped portion 23c is deformed downward in FIG. In particular, since the distance from the LCD connection portion 23a to the U-shaped portion 23c is short, the allowable amount of deformation is small, and when an excessive external force is applied,
There is a high possibility that the crimped portion between the LCD connection portion 23a and the LCD substrate 24 will peel off or the pattern in the flexible substrate 23 will be disconnected.

On the other hand, according to the embodiment of the present invention,
The deformation preventing member 17 (117) is
Since the excessive deformation of (113) is prevented, peeling of the press-bonded portion between the flexible substrate and the display device and disconnection of the pattern in the flexible substrate can be prevented.

However, the present invention is not limited to the illustrated embodiment. For example, in the above-described embodiment, the deformation preventing member 17 (117) is thinner than the LCD substrate 14 (114) in order to facilitate its shape processing, to prevent an increase in the number of components, and to reduce the manufacturing cost. It is formed integrally with the LCD holding frame 16 (116). However, the deformation preventing member for supporting the flexible substrate is LC
The display device 12 is formed separately from the D holding frame 16 (116).
It is also possible to attach to (112).

Further, the connection of the flexible substrate is as follows.
Not limited to LCD. For example, the flexible substrate is L
Instead of the CD substrate 14 (114), it may be connected to a display device having another display body, or may be connected to an electric component other than the display device. In short, a flexible substrate having a U-shaped bent portion may be provided with a deformation preventing member for preventing the flexible substrate from being excessively deformed.

[0022]

As described above, according to the present invention, since the deformation preventing member for preventing the flexible substrate from being excessively deformed is provided, it is possible to prevent problems such as breakage or disconnection of the flexible substrate with a simple configuration. .

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a flexible substrate support structure to which the present invention is applied.

FIG. 2 is a view taken in the direction of the arrow II in FIG.

FIG. 3 is a view illustrating a different embodiment of a support structure of a flexible substrate.

FIG. 4 is a perspective view showing an example of a conventional flexible substrate support structure.

FIG. 5 is a view taken in the direction of the arrow V in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Main board 12 Display device 13 Flexible board 13a LCD connection part 13c U-shaped part 13e Main board connection part 14 LCD board 14a Land part 15 LCD display part 16 LCD holding frame 16b Extension leg part 17 Deformation prevention member 17a Extension part 17b Flexible board support plate

Claims (8)

[Claims] 1. A flexible substrate having one end connected to an electric component and bent in a U-shape and the other end connected to a main substrate; and a deformation located inside the bent portion of the flexible substrate. A support structure for a flexible substrate, comprising: a prevention member; 2. The support structure according to claim 1, wherein the deformation preventing member supports the flexible substrate made of a rigid material. 3. The support structure according to claim 1, wherein the deformation preventing member is formed integrally with an electric component. 4. The flexible substrate supporting structure according to claim 1, wherein the deformation preventing member has a curved surface corresponding to an inner peripheral surface of a bent portion of the flexible substrate. . 5. The support structure for a flexible substrate according to claim 4, wherein the curved surface portion of the deformation preventing member is not in contact with the inner peripheral surface of the bent portion of the flexible substrate when no external force acts on the flexible substrate. . 6. The flexible substrate supporting structure according to claim 4, wherein the curved surface portion of the deformation preventing member contacts and supports the inner peripheral surface of the bent portion of the flexible substrate in a state where no external force acts on the flexible substrate. 7. The support structure according to claim 1, wherein the electric component is a flexible substrate that is a liquid crystal display. 8. The support structure according to claim 7, wherein the liquid crystal display has a frame for holding and holding the liquid crystal display, and the deformation preventing member is formed integrally with the frame. Substrate support structure.