JPH0774486A - Mounting structure of flexible printed wiring board - Google Patents

Abstract

PURPOSE:To provide mounting structure of a flexible wiring board improved in efficiency and reliability for mounting and removing. CONSTITUTION:A square hole 2 and a slit extended in a T-shape from one side center of the square hole are provided at the mounting part of a flexible printed wiring board, and a rib 5 is provided on a counter part on which the board is mounted. For mounting, the printed wiring board is pressed so that the slit may be deformed to catch the rib 5, whereas it is removed by moving the square hole 2 to the rib part 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of a mounting structure for mounting a flexible printed wiring board in a case of an electronic device, and more particularly to a mounting structure for a flexible printed wiring board which can be easily mounted and dismounted.

[0002]

2. Description of the Related Art With the increasing complexity of shapes of electronic equipment such as various office automation equipment and communication equipment, increase of design restrictions, miniaturization, etc., dimensions and shapes of printed circuit boards and cables installed in these equipment. Also, restrictions on conditions such as layout have become large, and as a result, the utility value of flexible printed wiring boards (hereinafter abbreviated as FPC) as means for connecting these has increased, and the frequency of their use has increased. FIG. 5 shows an example of a mounting structure in which such an FPC is mounted on a mounting target of an electronic device by a conventional technique. The figure shows multiple F
The state where the mounting holes provided in the PCs 21a, 21b, and 21c and communicating with each other are fitted to the protruding locking portions 25 provided in the mounting target 24 is shown. As is apparent from the figure, this conventional example has a drawback that the periphery of the mounting hole is lifted up because the mounting hole and the protruding locking portion are tightly engaged with each other. There is also a problem that the FPC 21c in the outer layer is most likely to drop off.

From such a point, a mounting structure as shown in FIG. 6 has been proposed (see Japanese Utility Model Publication No. 4-47996). This forms a protruding locking portion 35 on the attachment target 34, and
In the mounting structure for mounting the PC on the protruding locking portion,
A fixing mounting hole having a small opening area is provided in the FPC 31c of the outer layer, and a protruding locking portion is provided between the FPC 31c of the outer layer and the mounting target 34 as a mounting hole for insertion into the protruding locking portion 35.
Multiple FPs with mounting holes larger than 35 in diameter
This is a mounting structure in which C31a and 31b are arranged and the FPCs 31a and 31b in the inner layer are fixed by the FPC31 in the outer layer. A mounting structure having an L-shaped protruding locking portion as shown in FIG. 7 has also been proposed (see Japanese Utility Model Publication No. 4-47996). In the figure, 41a is an inner layer FPC, 41c is an outer layer FPC, 44 is an attachment target, and 45 is an L-shaped protruding locking portion. In this conventional example, a small mounting hole provided in the outer layer FPC 41c is fitted into the L-shaped protruding locking portion 45 to press the inner layer FPC 41a.

However, the above-mentioned improved mounting structure also has the following drawbacks. First, for the FPC of the outer layer, even though the diameter of the mounting hole is slightly smaller than the diameter of the protruding locking portion, the structure around the mounting hole is difficult to deform, so a large force is required for mounting. And Moreover,
There is variation in the diameter of the mounting hole and the diameter of the protruding locking part, so mounting becomes more difficult, and it may not be inserted anymore into the protruding locking part during insertion, so there is no certainty in mounting. . Secondly, the FPC of the outer layer is difficult to remove, as is clear from the deformation direction around the mounting hole. If you try to remove it forcibly, the FPC pattern will be damaged. Thirdly, when it is repeatedly attached and detached, the protruding locking portion is scratched or damaged. Fourth, it is for mounting purposes only and has no other effect. Fifth, with respect to the mounting structure including the L-shaped protruding locking portion, the mounting method is complicated and the workability is poor. Further, it is considered that a load of deformation is applied to a wide range of the FPC at the time of attachment, and when an element is soldered on the FPC, problems such as peeling occur.

[0005]

It is an object of the present invention to solve the problems of the prior art as described above, to improve the workability of attachment and detachment, to ensure the attachment, and to prevent the FPC and the protruding locking portion from being damaged. Another object of the present invention is to provide a mounting structure for a flexible wiring board, which can bring out additional effects.

[0006]

In a mounting structure in which a protruding locking portion is formed on a mounting target and a flexible printed wiring board is mounted on the protruding locking portion, a square hole is formed in the mounting portion of the flexible printed wiring board, and Equipped with a T-shaped slit from the center of one side of the hole, as a projecting locking part for attachment,
Equipped with rib-shaped mounting ribs.When mounting, the slits are deformed by pressing against the mounting ribs, and when removing, the square holes are moved to the mounting ribs for removal. In the above, when the flexible printed wiring board is in a state of being attached to the attachment target, a structure is provided in which a stopper rib for preventing the square hole from moving to the attachment rib side is provided in the attachment target, In the above structure, a ground pattern is provided at the flexible printed wiring board mounting contact portion that contacts the mounting rib, and at least a portion of the mounting rib that contacts the ground pattern is made conductive.

[0007]

In the mounting portion of the flexible printed wiring board, a square hole and a T-shaped slit from the center of one side of the square hole are provided.
The object to be mounted is provided with a rib for mounting as a protruding locking portion, and at the time of mounting, the slit portion is deformed by being pressed against the mounting rib, and is mounted.
At the time of dismounting, the square hole is moved to the mounting rib portion for dismounting, so that it can be easily mounted and dismounted without applying a large force. Also, when the flexible printed wiring board is attached to the mounting target, the mounting holes are provided with stopper ribs that prevent the rectangular holes from moving to the mounting rib side. There is no deviation. In addition, the flexible printed wiring board mounting contact portion that contacts the mounting rib is provided with a ground pattern, and the portion of the mounting rib that contacts the ground pattern is made conductive so that the ground of the flexible printed wiring board can be electrically connected to the mounting target. Connected.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a plan view showing an embodiment of a mounting portion of a flexible printed wiring board (FPC) according to the present invention. In the figure, reference numeral 1 is an FPC, 2 is a square hole provided in the FPC 1, 3 is a T-shaped slit provided in the FPC 1, and 31 is a round hole provided at both ends of one side of the T-shaped slit 3. The slit 3 is cut from the center of one side of the square hole 2. When the slit part is placed on a mounting rib (protruding locking part) provided on a mounting target and the FPC 1 is pressed downward, the A and B parts (see FIG. 1) whose three sides are separated are shown in FIG. As shown in FIG. 5, the ribs 5 are pushed by the mounting ribs 5 to be deformed into an arc shape and lifted upward. Then, the opening of the FPC 1 generated by the deformation and the mounting rib 5 are engaged as shown in the figure. Further, since the stopper rib 6 which is a small protrusion is arranged in the mounting target 4 in the positional relationship with the mounting rib 5 as shown in the figure, after the FPC 1 is mounted, the A and B parts are elastically moved to both sides. Due to the pressing force of the mounting rib 5 from the above, and the existence of the stopper rib 6 and the mounting rib 5, they cannot move in any direction.

To remove the FPC 1 from the mounting rib 5, the FPC is moved in the direction of the arrow to shift the square hole 2 to the mounting rib 5 portion as shown in FIG. That is, FPC1
, The portion engaged with the stopper rib 6 is floated upward, the FPC 1 is removed from the stopper rib 6, the FPC 1 is allowed to move freely and horizontally displaced, and the square hole 2 is aligned with the mounting rib 5 position. The FPC 1 may be pulled out upward.
Although the length l ₂ of the stopper rib is smaller than the width l ₁ of the square hole in the embodiment of FIG. 2, l ₂ may be substantially equal to l ₁ . By doing so, it is possible to prevent unnecessary force from acting on the FPC 1 and to prevent the FPC 1 from moving in the longitudinal direction of the stopper rib 6.

FIG. 4 shows a modified embodiment of the FP which is in contact with the mounting rib 5 when the FPC 1 is mounted.
It is possible to provide a grounding pattern 11 on the mounting contact portion of C1 and make at least a portion of the mounting rib 5 in contact with the grounding pattern 11 conductive to electrically connect the ground of the FPC 1 to the mounting rib 5. is there. In the above, in order to make the mounting rib 5 conductive, for example, surface treatment by electroless plating is performed. The electrically conductive portion may include not only the portion of the attachment rib 5 that comes into contact with the ground pattern 11 but also the inner surface of the attachment object (case) 4. In this way, the ground pattern 11 of the FPC 1 can be electrically connected to the attachment target 4 without using a special grounding cable.

When plastic is used as the material of the attachment target 4, in order to make it conductive, a method using aluminum vapor deposition is also possible in addition to the above electroless plating. The same effect can be obtained even if the material of the attachment target 4 is metal. By connecting the ground pattern 11 of the FPC 1 to the attachment target 4 as described above, it is possible to prevent static electricity, electrical noise from the outside, unnecessary radiation to the outside, and improve the reliability of the device.

[0012]

As described above, the FP according to the present invention
With the C-mounting structure, the FPC can be easily attached to and detached from the object to be attached without applying a large force, resulting in good operability
There is certainty in mounting, and it does not damage the FPC or protruding locking part. Further, when the FPC is attached to the attachment target, the attachment of the stopper rib for preventing the square hole from moving to the attachment rib side causes the square hole to shift to the attachment rib side. It is also effective to increase the certainty of the mounting. Furthermore, F
Since the ground of the PC is electrically connected to the object to be mounted, it can be a measure against static electricity, electric noise from the outside, unnecessary radiation to the outside, and the reliability of the device can be improved.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a mounting portion of an FPC according to the present invention.

FIG. 2 is an FPC according to an embodiment of a mounting structure according to the present invention.
It is a perspective view which shows the attached state of the attachment target.

FIG. 3 is a perspective view for explaining an FPC removal procedure according to an embodiment of the present attachment structure.

FIG. 4 is a cross-sectional view showing another embodiment of the mounting structure according to the present invention.

FIG. 5 is a sectional view showing an example of a mounting structure according to a conventional technique.

FIG. 6 is a sectional view showing another example of a mounting structure according to the prior art.

FIG. 7 is a cross-sectional view showing another example of a mounting structure according to the related art.

[Explanation of symbols]

1 ... FPC, 2 ... square hole, 3 ... slit, 4 ... attachment target,
5 ... Rib for mounting, 6 ... Rib for stopper, 11 ... Ground pattern.

Claims (3)

[Claims] 1. A mounting structure in which a protruding locking portion is formed on a mounting target and a flexible printed wiring board is mounted on the protruding locking portion, wherein a square hole is formed in the mounting portion of the flexible printed wiring board, and a center of one side of the square hole. A slit extending in a T-shape from the above, and a mounting rib formed in a rib shape as a protruding locking portion on the mounting target, and at the time of mounting, the slit portion is deformed by mounting the mounting rib, The structure for mounting a flexible printed wiring board is characterized in that the above-mentioned square hole is moved to the mounting rib portion to be removed when detaching. 2. In the above structure, when the flexible printed wiring board is attached to the attachment target, a stopper rib for preventing the square hole from moving toward the attachment rib side is provided on the attachment target. The mounting structure for a flexible printed wiring board according to claim 1, wherein: 3. In the above structure, a ground pattern is provided at a flexible printed wiring board mounting contact portion that contacts the mounting rib, and at least a portion of the mounting rib that contacts the ground pattern is made conductive. The flexible printed wiring board mounting structure according to claim 1 or 2.