JP2008053540A - Printed circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printed circuit board including a fastening structure for preventing stress from being applied to an electronic component or the like on the printed circuit board. <P>SOLUTION: A printed circuit board 10 is provided which includes the fastening structure composed of a fastening member 13 including a fastening element inserting hole 12 for inserting a fastening element 11, and a connection means 14 for connecting the printed circuit board 10 to the relevant fastening member 13 so as to freely swing the printed circuit board. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a printed circuit board, and more particularly to a printed circuit board having a fastening structure that prevents stress applied to electronic components and the like on the printed circuit board.

  Generally, printed circuit boards on which electronic components are mounted by soldering are used for electronic devices. Among electronic components mounted on a printed circuit board, ICs (Integrated Circuits / semiconductor integrated circuits) such as QFP (Quad Flat Package) and BGA (Ball Grid Array) are multi-functional and highly integrated. As the number of terminals increases, products with many terminals and large packages have been commercialized, and electronic devices with large packages such as QFP and BGA having many terminals are mounted on electronic devices. More and more printed circuit boards are being used. After mounting these electronic components by soldering, the printed circuit board is inserted into an insertion hole provided at a predetermined position of the printed circuit board, thereby inserting a fastening element such as a screw into the casing of the electronic device. It is common to stop and fix. However, the conventional fixing method has two major problems. The first problem is that the printed circuit board is often warped due to the influence of high heat generated during soldering when mounting electronic components, and the printed circuit board having such warpage is screwed into the casing of the electronic device or the like. When fastening and fixing, in the conventional printed circuit board, stress is applied to the electronic component of a large package such as QFP or BGA having many terminals, which may cause deterioration in characteristics or destruction of the electronic component, This is a problem that the soldering of the terminal is removed. The second problem is that when the electronic device is accidentally dropped, the impact due to dropping or the like is transmitted from the housing of the electronic device to the printed circuit board, and the wiring structure of the printed circuit board is deformed, This is a problem that the mounted electronic component is deteriorated in characteristics or destroyed, or the terminals of the electronic component are unsoldered.

  In order to deal with the first problem, for example, Patent Document 1 discloses a printed circuit board as shown in FIG. In the printed circuit board 1, holes 1a for inserting fastening elements such as screws are provided at predetermined positions, and slits 1b are extended from the periphery of the printed circuit board 1 to both sides of the insertion hole 1a. By providing the slit 1b, even when the printed circuit board 1 having warpage is screwed and fixed to the housing or the like, stress due to screwing is absorbed by the slit 1b. It is possible to prevent the characteristic deterioration and destruction of the electronic component 1c and to prevent the soldering of the terminals of the electronic component 1c from being removed.

  In order to cope with the second problem, for example, Patent Document 2 discloses a printed circuit board as shown in FIG. The printed circuit board 2 is provided with a hole 2a for inserting a fastening element such as a screw at a predetermined position, and a plurality of slits 2b are formed so as to surround the outer periphery of the insertion hole 2a. A connecting portion 2d is formed between the two. According to this printed circuit board 2, since the impact transmitted from the housing to the printed circuit board 2 when the electronic device is dropped or the like is absorbed by the slit 2b and the connecting portion 2d, the electronic component 2c on the printed circuit board 2 is absorbed. Thus, it is possible to prevent the deterioration and destruction of the characteristics of the electronic component 2c and to prevent the soldering of the terminals of the electronic component 2c.

Japanese Utility Model Publication No. 5-411169 JP 2002-344092 A

  However, as shown in FIG. 6B, according to the printed circuit board 1 of Patent Document 1, in the direction where the slit 1b is not provided when viewed from each insertion hole 1a, the stress due to screwing is caused by the slit 1b. Since it is not absorbed, it is not possible to prevent the characteristic deterioration and destruction of the electronic component 1c mounted on the printed circuit board 1 in the region 1d indicated by the broken line, and the terminals of the electronic component 1c may be unsoldered. The problem that cannot be prevented is left unsolved.

  Furthermore, according to the printed circuit board 2 of Patent Document 2, in order to make it difficult to transmit an impact when dropped or the like to the mounted electronic component 2c, the slits 2b are formed large, and the connecting portions 2d between the slits 2b are formed. Is required to be formed small. Accordingly, the slit 2b and the connecting portion 2d may be broken depending on the degree of impact when the electronic component is dropped. In this case, the printed circuit board 2 cannot be fixed to the casing or the like of the electronic device, and a new impact due to the split of the slit 2b and the connecting portion 2d is directly transmitted to the printed circuit board 2, so that the printed circuit Problems such as deformation of the wiring structure of the substrate 2, deterioration of characteristics and destruction of the mounted electronic component 2c, and unsoldering of terminals of the electronic component 2c are left unsolved.

  Therefore, the present invention solves the problems that have not been solved in the conventional printed circuit board described above and solves the first problem and the second problem at the same time on the printed circuit board. It is an object of the present invention to provide a printed circuit board having a fastening structure that prevents stress applied to an electronic component or the like.

  To achieve the above object, the present invention provides a fastening structure comprising a fastening member having a fastening element insertion hole for inserting a fastening element, and a connecting means for swingably connecting a printed circuit board to the fastening member. Provided is a printed circuit board having Furthermore, the present invention provides a printed circuit board having a fastening structure in which the fastening member is a member separated from the printed circuit board and the connecting means is an elastic wire. Furthermore, the present invention provides a printed circuit board having a fastening structure comprising an integral elastic plate having a perforated head forming a fastening member and a leg forming a connecting means.

  According to the printed circuit board having the fastening structure disclosed in the present invention, when the printed circuit board having warpage is screwed and fixed to the housing or the like of the electronic device, characteristic deterioration or destruction of the electronic component mounted on the printed circuit board is called. The occurrence of inconvenience can be prevented, and the inconvenience that the soldering of the terminals of the electronic component is removed can be prevented. Further, when an electronic device is accidentally dropped by the printed circuit board having the fastening structure disclosed in the present invention, an impact due to the drop or the like is transmitted from the casing of the electronic device to the printed circuit board, and the printed circuit It is possible to prevent inconveniences such as deformation of the wiring structure of the substrate, deterioration of characteristics and destruction of the mounted electronic component, and unsoldering of terminals of the electronic component.

Specific embodiments according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view illustrating a printed circuit board according to a first embodiment of the present invention. The printed circuit board 10 includes a fastening member 13 having a fastening element insertion hole 12 for inserting a screw 11 as a fastening element, and a jumper 14 that is an elastic wire as a connecting means for connecting the fastening member 13 to the printed circuit board 10. The fastening structure 100 is made of On the surface of the printed circuit board 10, a plurality of electronic components (not shown) including a large package electronic component 15 such as QFP and BGA are mounted, and a wiring structure connecting the electronic components is formed. The fastening member 13 separated from the printed circuit board 10 is swingably connected to the printed circuit board 10 via a jumper 14. Further, the fastening member 13 is screwed and fixed to the housing 16 of the electronic device by inserting the screw 11 into the fastening element insertion hole 12.

  According to the printed circuit board 10 having the first fastening structure 100 described above, even when the printed circuit board 10 has a warp, the fastening member 13 screwed to the housing 16 of the electronic device and the Since the printed circuit board 10 is slidably fastened via the jumper 14, the stress caused by screwing can be almost completely absorbed by the jumper 14. As a result, the conventional problem when the printed circuit board 10 is screwed and fixed to the casing 16 of the electronic device, that is, the characteristic deterioration or destruction of the electronic components mounted on the printed circuit board 10, Can almost completely prevent the problem that the soldering of the terminals of the electronic component is disengaged. Also, conventional problems in the case where an electronic device is accidentally dropped, that is, deformation of the wiring structure of the printed circuit board 10, deterioration or destruction of characteristics of the mounted electronic component, and terminals of the electronic component It is possible to almost completely prevent the problem that the soldering is removed.

Here, a method of manufacturing the printed circuit board 10 having the fastening structure 100 shown in FIG. 1 in the above-described first embodiment will be briefly described with reference to FIG. First, as shown in FIG. 2A, perforations 17 are formed on the printed circuit board 10 at portions that are later separated from the printed circuit board 10 as the fastening members 13. Next, as shown in FIG. 2 (b), the fastening member 13 is connected to the printed circuit board main body 10 by a perforation 17. However, the fastening member 13 and the printed circuit board main body 10 are connected by a jumper 14, Fix by soldering. Further, as shown in FIG. 2C, the fastening member 13 is divided from the printed circuit board 10 by breaking the perforation 17. Thus, the printed circuit board 10 having the fastening structure 100 according to the first embodiment of the present invention shown in FIG. 1 can be manufactured. Note that the size of the fastening element insertion hole 12 provided in the fastening member 13 is slightly larger as long as there is no hindrance to screwing in order to ensure the alignment accuracy between the housing of the electronic device and the printed circuit board 10. It is necessary to form it.

  In the method of manufacturing the printed circuit board 10 having the first fastening structure 100 described above, it is necessary to divide the fastening member 13 from the printed circuit board main body 10. In some cases, the housing and the printed circuit board 10 are misaligned so that screwing is difficult. As a modified example of the fastening member 13 that can avoid these problems in manufacturing the printed circuit board 10, a printed circuit board 10a having a second fastening structure 200 will be described below with reference to FIGS. The manufacturing method will be described with reference to (b). First, on the printed circuit board 10a in FIG. 3A, a gap 18a and a perforation 17a are formed as a fastening member 13a, which will be separated later from the printed circuit board 10a, and the fastening member 13a The printed circuit board main body 10a is connected by a jumper 14a and soldered. Next, the perforation 17a is broken to divide the fastening member 13a from the printed circuit board 10a. As shown in FIG. 3B, the fastening member 13a thus divided is slid in an oblique direction while being connected to the printed circuit board main body 10a by the jumper 14a, and is fitted and disposed in the gap 18a. The fastening member 13a shown in FIG. 3B formed in this way has a slight margin in the distance from the printed circuit board 10a compared to the fastening member 13 shown in FIG. 1, and the degree of freedom of the fastening member 13a. Therefore, bending of the jumper 14a and screwing to the housing of the electronic device are facilitated accordingly.

Next, the printed circuit board 10b having the third fastening structure 300 will be described with reference to FIGS. 3C and 3D together with its manufacturing method. On the printed circuit board 10b of FIG. 3 (c), a discard board 19b is provided in a portion that is later separated from the printed circuit board 10b as the fastening member 13b, and between the discard board 19b and the printed circuit board 10b, and A perforation 17b is formed between the discard board 19b and the fastening member 13b, and the fastening member 13b and the printed circuit board body 10b are connected by a jumper 14b and soldered. Next, the fastening member 13b is divided from the printed circuit board 10b by breaking these perforations 17b. By removing the discarded substrate 19b, as shown in FIG. 3D, the fastening member 13b connected to the printed circuit board main body 10b by the jumper 14b can be formed while holding the gap of the discarded substrate 19b. . The fastening member 13b shown in FIG. 3 (d) formed in this way is further spaced from the printed circuit board 10b as compared to the fastening member 13a shown in FIG. 3 (b). Since the degree of freedom is further increased by that amount, bending of the jumper 14b and screwing to the housing of the electronic device are further facilitated. It should be noted that the size of the fastening element insertion holes 12a and 12b provided in the fastening members 13a and 13b may be hindered by screwing in order to ensure the accuracy of alignment between the casing of the electronic device and the printed circuit boards 10a and 10b. It is necessary to form it slightly larger in such a range.

According to the printed circuit boards 10a and 10b having the fastening structures 200 and 300 made of the fastening member 13a of FIG. 3B or the fastening member 13b of FIG. 3D, the fastening structure 100 made of the fastening member 13 of FIG. As in the case of the printed circuit board 10 having the fastening member 13a or the fastening member 13b screwed to the housing 16 of the electronic device and the printed circuit, even when the printed circuit boards 10a and 10b have warpage. Since the boards 10a and 10b are slidably fastened via the jumpers 14a and 14b, the stress caused by screwing can be almost completely absorbed by the jumpers 14a and 14b. As a result, conventional problems when the printed circuit boards 10a and 10b are screwed and fixed to the casing 16 of the electronic device, that is, deterioration of characteristics and destruction of electronic components mounted on the printed circuit boards 10a and 10b are caused. The problem, and further, the problem that the soldering of the terminals of the electronic component is removed can be almost completely prevented. Also, conventional problems in the case where an electronic device is accidentally dropped, that is, deformation of the wiring structure of the printed circuit boards 10a and 10b, characteristic deterioration or destruction of the mounted electronic component, and further electronic component It is possible to almost completely prevent the problem that the soldering of the terminals of the terminal is unsoldered.

  Embodiment 1 according to the present invention has been described in detail so far. Hereinafter, a printed circuit board having a fourth fastening structure in which a fastening member and a connecting means (jumper in Embodiment 1) are integrated will be described. Example 2 will be described with reference to the drawings.

FIG. 4 is a partial perspective view illustrating a printed circuit board having a fastening structure 400 according to a second embodiment of the present invention. The printed circuit board 10c is an integral elastic plate having a fastening element insertion hole 12c for inserting a screw 11c as a fastening element in the head and having a leg portion 20 as a connecting means for connecting to the printed circuit board 10c. A fastening structure 400 made of a certain earth lug 21 is provided. On the surface of the printed circuit board 10c, a plurality of electronic components including a large package electronic component 15 such as QFP and BGA are mounted, and a wiring structure connecting the electronic components is formed. The ground lug 21 separated from the printed circuit board 10c is connected to the printed circuit board 10c through the leg portion 20 so as to be swingable. Further, the ground lug 21 is screwed and fixed to the housing 16 of the electronic device by inserting the screw 11c into the fastening element insertion hole 12c.

According to the printed circuit board 10c having the fastening structure 400 described above, even when the printed circuit board 10c has a warp, the ground lug 21 screwed and fixed to the casing 16 of the electronic device and the printed circuit board 10c. Are pivotably fastened via the leg portion 20 of the earth lug 21 made of an elastic plate, so that the stress due to screwing can be absorbed almost completely by the leg portion 20. As a result, the conventional problem when the printed circuit board 10c is screwed and fixed to the casing 16 of the electronic device, that is, the problem that the electronic component mounted on the printed circuit board 10c is deteriorated or destroyed, Can almost completely prevent the problem that the soldering of the terminals of the electronic component is disengaged. In addition, the conventional problems in the case where the electronic device is accidentally dropped, that is, the deformation of the wiring structure of the printed circuit board 10c, the deterioration or destruction of the characteristics of the mounted electronic component, and the terminal of the electronic component It is possible to almost completely prevent the problem that the soldering is removed.

Here, a manufacturing method of the printed circuit board 10c having the fourth fastening structure shown in FIG. 4 in the above-described second embodiment will be briefly described with reference to FIG. First, as shown in FIG. 5A, on the printed circuit board 10c, a portion of the printed circuit board 10c corresponding to a portion where the earth lug 21 as the connecting means is arranged is discarded as a substrate 19c. Next, as shown in FIG. 5B, the leg portion 20 of the ground lug 21 is inserted into a predetermined portion of the printed circuit board 10c, and is fixed by soldering. Further, as shown in FIG. 5C, the ground lug 21 with the leg portion 20 fixed to the printed circuit board 10c is bent in the direction of the arrow shown in FIG. In this manner, the printed circuit board 10c having the fourth fastening structure 400 according to the second embodiment of the present invention shown in FIG. 4 can be manufactured. In order to ensure the accuracy of alignment between the housing of the electronic device and the printed circuit board 10c, the size of the fastening element insertion hole 12c provided in the head of the earth lug is slightly larger as long as there is no hindrance to screwing. It is necessary to form it.

  As described in the first embodiment and the second embodiment, the printed circuit board having the fastening structure according to the present invention is used when the printed circuit board having warpage is screwed and fixed to a housing or the like of the electronic device, or the electronic device. If the product is accidentally dropped, the wiring structure of the printed circuit board may be deformed, or the characteristics of the mounted electronic components may be degraded or destroyed even if there is a stress associated with screwing or an impact associated with dropping. Or inconveniences such as unsoldering of the terminals of the electronic component can be prevented. Further, as a secondary effect of the printed circuit board having the fastening structure according to the present invention, the electronic component mounted on the printed circuit board is heated / cooled according to the use state of the electronic device, and the printed circuit board expands. Even in the case of contraction, since the printed circuit board and the fastening member are fastened through the connecting means so as to be swingable, the stress on the printed circuit board can be reduced. In addition, even when the screw fixing location of the housing of the electronic device and the screw fixing location of the corresponding fastening member are in a positional relationship with each other, by bending a fastening member such as a jumper or a ground lug Easy installation. Furthermore, it is also possible to arrange the screwing fixing part perpendicular to the printed circuit board.

As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to the above-mentioned Example, A various deformation | transformation implementation is possible within the range of the summary of this invention.

1 is a perspective view illustrating a printed circuit board having a fastening structure according to a first embodiment of the present invention. It is a fragmentary perspective view of the printed circuit board which shows each manufacturing process (a), (b), (c) of the manufacturing method of the printed circuit board which has the fastening structure by Example 1 of this invention. It is a fragmentary perspective view which shows the two modifications of the fastening member by Example 1 of this invention with the manufacturing process (a), (b), (c), (d). It is a fragmentary perspective view which shows the printed circuit board which has the fastening structure by Example 2 of this invention. It is a fragmentary perspective view of the printed circuit board which shows each manufacturing process (a), (b), (c) of the manufacturing method of the printed circuit board which has the fastening structure by Example 2 of this invention. It is a perspective view which shows the aspect of the conventional printed circuit board in (a) and (b), respectively. It is a top view which shows the conventional printed circuit board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printed circuit board 1a Fastening element insertion hole 1b Slit 1c Electronic component 2 Printed circuit board 2a Fastening element insertion hole 2b Slit 2c Electronic component 2d Connection part 10 Printed circuit board 11 Screw 12 Fastening element insertion hole 13 Fastening member 14 Jumper 15 Electronic component 16 Housing 17 Perforation 18 Cavity 19 Discarded Board 20 Leg 21 Ground Lug 100 Fastening Structure 200 Fastening Structure 300 Fastening Structure 400 Fastening Structure

Claims (3)

  A printed circuit board having a fastening structure comprising a fastening member having a fastening element insertion hole for inserting a fastening element, and a connecting means for swingably connecting the printed circuit board to the fastening member.   2. The printed circuit board having a fastening structure according to claim 1, wherein the fastening member is a member separated from the printed circuit board, and the connecting means is an elastic wire. 2. The printed circuit board having a fastening structure according to claim 1, wherein the printed circuit board comprises an integral elastic plate having a perforated head forming the fastening member and a leg forming the connecting means.

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