JP2001196708A - Method and device for preventing deflection of printed board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and jig for preventing deflection of a printed board, where even with a longer slit, the deflection at that part of printed board is surely prevented and strength is controlled easily, while reducing waste. SOLUTION: The reflection of a printed board is prevented by inserting a deflection preventive jig in a slit. The deflection preventive jig comprises, for example, a pin-like body part 12 and a flange parts 13a and 13b provided on both ends of the body part 12, and during rotation around the axis after inserted in the slit, both flange parts 13a and 13b hit substrate surfaces 2a and 3a as well as 2b and 3b, while bridging a printed board 2 and a waste substrate 3. A part of the slit may be widened, so that the deflection preventive jig is inserted into that part. The deflection preventive jig may comprise a material, whose thermal expansion factor is larger than that of the material of a sheet substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for preventing warpage of a printed circuit board.

[0002]

FIG. 13 is a plan view showing the structure of a sheet substrate. As shown in FIG. 1, the sheet substrate 1 has a rectangular shape including a printed substrate 2 and a disposal substrate 3 provided around the printed substrate 2. In the case where the printed circuit board 2 is irregular (not square) as in the illustrated example, it is difficult to mount electronic components. Therefore, a discarded substrate 3 is provided around the printed circuit board 2 to form a square in which electronic components can be easily mounted. Note that even when the printed board is rectangular, a discarded board may be provided around the printed board. The sheet substrate 1 is generally made of glass epoxy resin.

The printed circuit board 2 is provided with printed wiring (not shown), and cream lands are printed (applied) on lands, on which various electronic components such as the IC 4 and the connector 5 are mounted. The discard substrate 3 has a mounter reference hole 6 serving as a reference position for mounting the electronic component on the printed circuit board 2.

[0004] The boundary between the printed board 2 and the discarded board 3 has intermittently formed slits 7a to 7e. After the electronic components are mounted on the printed board 2, perforations (slits) between the slits are formed. The printed board 2 is separated from the discarded substrate 3 by cutting the printed circuit board and the discarded substrate 8a to 8e with a mold or the like.

[0005]

However, for example, FIG.
In the case where the connector 5 is mounted in a state protruding from the end of the printed circuit board 2 as shown in FIG. 3, if a perforation is provided at the mounting position of the connector 5, the connector 5 becomes an obstacle and the perforation is cut. You will not be able to do it. For this reason, the slit 7a at the mounting position of the connector 5 must be longer than the other slits 7c to 7e.

In addition, because the end of the printed circuit board 2 needs to be straightened due to restrictions on products, the interval between the perforations 8a and 8b is increased as in the slit 7b and the distance between the other slits 7c to 7e is increased. Sometimes it has to be long.

When the slits 7a and 7b are lengthened in this way, the printed board 2 warps in the slits 7a and 7b in the electronic component mounting step (particularly, the soldering step in a reflow furnace), and the solder In some cases, the mounting quality was degraded.

In order to facilitate the work of separating the printed circuit board 2, it is desirable to reduce the number of perforations as much as possible. However, in order to achieve this, it is necessary to widen the perforation interval to make the slit longer, and if the slit is made longer, the above-described warping problem occurs.

Japanese Patent Application Laid-Open No. 5-160528 discloses a technique in which a slit is filled with an ultraviolet curable resin to prevent a printed board from warping. However, in this case, if the adhesive strength between the resin and the substrate is low, the resin will be peeled off during mounting. Conversely, if the adhesive strength is too strong, the resin will not peel off when the substrate is divided. Difficult to manage. In addition, once used resin is difficult to reuse and is discarded.

Japanese Patent Application Laid-Open No. 8-8535 discloses a technique in which a copper foil is provided around a perforation to prevent a printed board from warping. However, this cannot solve the problem of the warpage of the printed circuit board when the slit is lengthened.

Therefore, in view of the above problems, the present invention can reliably prevent the printed board from warping at this portion even if the slit is lengthened, and can easily control the strength and reduce waste. An object of the present invention is to provide a method and an apparatus for preventing warpage of a printed circuit board which can contribute to reduction.

[0012]

Means for Solving the Problems A first method for solving the above problems is described below.
The method for preventing warpage of a printed board according to the present invention has slits formed intermittently at the boundary between the printed board and the discarded board, and the printed board is discarded by cutting perforations between these slits. A method for preventing warpage of the printed board in a sheet board configured to be separated from the board, wherein the warpage of the printed board is prevented by fitting a warpage prevention tool into the slit. .

The method for preventing warpage of a printed circuit board according to a second aspect of the present invention is the method for preventing warpage of a printed circuit board according to the first aspect of the present invention, wherein a recess is formed in the slit on the side of the discarded substrate to partially widen the slit. It is characterized in that the warpage preventing device is fitted into the widened portion.

Further, the printed board warpage preventing device of the third invention has slits formed intermittently at the boundary between the printed board and the discarded board, and the perforations between these slits are cut. A sheet substrate configured so that the printed circuit board is separated from the discard substrate by a tool that prevents the printed circuit board from warping, wherein the tool is fitted into the slit to prevent the printed circuit board from warping. It is characterized by having done.

The printed circuit board warpage preventing device of the fourth invention is the printed circuit board warpage preventing device of the third invention,
It has a pin-shaped main body, and flanges provided at both ends of the main body. The width of the main body is substantially equal to the width of the slit, and at least one of the flanges has a vertical and horizontal length. The width is less than the width of the slit and the length is greater than the width of the slit, when inserted from one of the flanges side through the slit and rotated around the axis, the two flanges respectively with the printed circuit board It is characterized in that it is arranged so as to straddle the discarded substrate and contact these substrate surfaces.

A fifth aspect of the present invention provides the printed circuit board warpage prevention device according to the third invention.
The length is set to be slightly larger than the width of the slit and smaller than the width of the slit, and after insertion into the slit, it is press-fitted into the slit by rotating around an axis. It is characterized by having done.

The printed circuit board warpage preventing device of the sixth invention is the printed circuit board warpage preventing device of the third invention,
A pin-shaped member, having a width slightly larger than the width of the slit, and forming a tapered surface at one end to make the width of the end surface smaller than the width of the slit. Thereby, the slit is press-fitted into the slit from one end side.

A printed board warpage preventing device according to a seventh aspect of the present invention is the printed circuit board warping preventing device according to the third aspect of the present invention.
A pair of leg portions having spring properties are provided on the collar portion, and the collar portion is longer than the width of the slit, and the pair of leg portions is widened toward the distal end side and the maximum width is set to the width of the slit. The pair of legs is formed to be slightly wider than the pair of legs and press-fit into the slit while being bent inward.

An eighth aspect of the present invention provides the printed circuit board warpage preventing device according to the seventh aspect of the present invention.
The pair of legs is bent from the middle, and the width of the tip is smaller than the width of the slit.

The printed circuit board warpage preventing device of the ninth invention is the printed circuit board warpage preventing device of the third invention,
It has a pin-shaped main body fitted into the slit and a brim provided at one end of the main body and in contact with the substrate surface, and is formed of a material having a larger coefficient of thermal expansion than the material of the sheet substrate. The slit is firmly fitted into the slit by thermal expansion during heating.

The warp preventing device for a printed board according to the tenth aspect of the present invention is the same as the warping preventing device for a printed board according to the third, fourth, fifth, sixth, seventh, or eighth aspect. It is formed of a material having a high coefficient of thermal expansion, and is configured to be more firmly fitted into the slit by thermal expansion during heating.

[0022]

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

<Embodiment 1> FIG. 1 is a plan view of a sheet substrate showing a state in which a warpage preventing device according to Embodiment 1 of the present invention is fitted in a slit, and FIG. 2 is a perspective view of the warping preventing device. is there. FIG. 3A is a plan view showing a state in which the warp preventing device is inserted into a slit, and FIG. 3B is a plan view of FIG.
3A is a cross-sectional view taken along line AA of FIG. 3, and FIG. 3C is a plan view showing a state in which the warpage preventing device is inserted into a slit and rotated.
FIG. 3D is a sectional view taken along line BB of FIG.

As shown in FIG. 1, a warpage preventing device 11 is fitted in the slits 7a and 7b of the sheet substrate 1.
Since the configuration of the sheet substrate 1 is the same as that of FIG.
The description here is omitted.

As shown in FIG. 2, the warpage preventing device 11 has a pin-shaped main body 12 and flanges 13a and 13b provided at both ends of the main body 12. Body portion 12 is formed in a cylindrical shape, and a width (diameter) d ₂ is equal to the width d ₁ of the slit 7a. Collar 13
a, 13b, the length of the vertical and horizontal, and the length d ₄ equal to the width d ₁ of the slit 7a, has become a large length d ₃ than the width d ₁ of the slit 7a. The flanges 13a, 13b
Length d ₄ may be at less than the width of the slit 7a.

In order to fit the warpage preventing tool 11 into the slit 7a, as shown by an arrow C in FIG.
From the brim portion 13b side (or from the brim portion 13a side)
It is inserted through the slit 7a. The state after insertion is shown in FIG.
(B).

Subsequently, the warp preventing device 11 is rotated by 90 ° around the axis as shown by an arrow D in FIG.
The state shown in (c) and (d) is assumed. At this time, the two brim portions 13a and 13b straddle the printed board 2 and the discarded board 3, and are in contact with these board surfaces 2a and 3a and 2b and 3b, respectively. That is, the brim portion 13a and the brim portion 13b
Thus, the printed board 2 and the discarded board 3 are integrally held. Similarly, as shown in FIG. 1, the warpage prevention tool 11 is fitted into the slit 7b.

Therefore, for example, when the sheet substrate 1 is conveyed to a reflow furnace and heated, the slits 7a and 7b cause the printed circuit board 2 to intervene via the warp preventing device 11 and the discarded substrate 3 fixed to the conveying device. Even if the slits 7a and 7b are long, the printed circuit board 2
Warpage can be reliably prevented. In other words, the use of the warpage prevention tool 11 makes it possible to lengthen the slit and reduce the number of perforations, thereby facilitating the work of separating the printed circuit board.

Further, since the warpage prevention tool 11 is firmly fitted and can be easily removed when the printed circuit board is cut off by cutting the perforation, the strength management as in the case of filling the slit with resin is performed. There is no difficulty,
In addition, since it can be reused, it also contributes to the reduction of waste.

When the anti-warpage tool 11 is fitted before applying the cream solder on the printed circuit board, the brim portions 13a and 13b contact the solder print mask on the printed circuit board in order to print the cream solder. It is necessary to make it thin enough so as not to disturb it.

In the above description, both the flanges 13a and 13b have the same shape. However, the present invention is not limited to this. Only one of the flanges 13a and 13b may have the above shape. For example, the flange portion 13b is the length and width of less than the width d ₁ of the slit 7a length and the slit 7a
May be larger than the width d _{1 of the} slit 7a, and the length of the flange portion 13a may be larger than the width d _{1 of the} slit 7a. In this case, the warpage preventing device 11 is inserted into the slit 7a from the side of the flange portion 13b.

<Embodiment 2> FIG. 4 is a perspective view of a warpage preventing device according to Embodiment 2 of the present invention, and FIG. 5 (a) is a plan view showing a state where the warpage preventing device is inserted into a slit. 5
(B) is a plan view showing a state in which the warpage preventing device is inserted into a slit and rotated. Note that the overall configuration of the sheet substrate is the same as in the first embodiment,
The description and illustration here are omitted.

As shown in FIG. 4, a rectangular concave portion 22 is formed on the side of the discard substrate 3 of the slit 7a, whereby a part of the slit 7a is widened. On the other hand, the warpage preventing member 21 is of pin-shaped, the width d ₅ of the length and width and the length larger d ₆ slightly larger than the width d ₅ of the widened parts 7a-1 of the slit 7a widened parts 7a-1 The length d ₇ is smaller than the length d ₇ . Also, the width d of the widened portion 7a-1
Both end surfaces 21a, 21b slightly larger than ₅
Are formed in an arc shape.

In order to fit the warpage preventing member 21 into the slit 7a, the warping preventing member 21 is inserted into the widened portion 7a-1 of the slit 7a as shown by an arrow E in FIG. The state after insertion is shown in FIG. Then, by rotating the warpage prevention tool 21 around the axis as shown by the arrow F in FIG. 5A, the warp prevention tool 21 is pressed into the widened portion 7a-1. Thus, the warpage preventing tool 21 is firmly fitted into the slit 7a. Although not shown, similarly, a widened portion is formed in the slit 7b, and the warpage preventing tool 21 is fitted.

Therefore, for example, when the sheet substrate 1 is heated in a reflow furnace, the printed circuit board 2 is supported by the discarded substrate 3 via the warpage preventing device 21 in the slits 7a and 7b, so that the slits 7a and 7b are long. Also, it is possible to prevent the printed board 2 from being warped at this portion. In addition, by using the warpage prevention tool 21, the number of perforations can be reduced and the work of separating the printed circuit board can be facilitated.

Also, since the warpage preventing tool 21 is firmly fitted and detaches at the same time as the printed circuit board 2 is cut by cutting the perforations, it is difficult to control the strength as in the case where the slit is filled with resin. And it is reusable, which also contributes to the reduction of waste.

Further, a concave portion is formed on the discarded substrate side of the slits 7a and 7b to widen a part of the slits 7a and 7b, and the warp preventing device 21 is fitted into the widened portion.
As a result, the size of the warp preventing device 21 is increased, and handling is facilitated, and the printed circuit board 2 can be reliably supported. In addition, both end surfaces 21a, 21b of the warp preventing device 21 are provided.
Is an arc shape in the above description, but the shape is not limited to an arc, and may be, for example, a smooth curve whose radius gradually changes, or a combination of a straight line and these curves.

<Embodiment 3> FIG. 6A is a perspective view of a warpage prevention device according to Embodiment 3 of the present invention, FIG. 6B is a plan view of the warpage prevention device, and FIG. Is G- in FIG.
FIG. 3 is a sectional view taken along line G of FIG. FIG. 7A is a plan view showing a state in which the warpage preventing tool is fitted in a slit.
FIG. 8B is a sectional view taken along line HH of FIG. Note that the overall configuration of the sheet substrate is the same as that of the first embodiment, and a description and illustration thereof will be omitted.

As shown in FIG. 6, a rectangular concave portion 22 is formed on the side of the discard substrate 3 of the slit 7a, whereby a part of the slit 7a is widened. On the other hand, the warpage prevention tool 31 has a pin shape and a square shape in a plan view. And this warpage prevention tool 31
Has a greater width d ₈ slightly larger than the width d ₅ of the widened parts 7a-1 of the slit 7a, and, on one end tapered surface 31
a and the width d ₉ of the end face 31 b is increased by the widened portion 7 a-1.
It is made smaller than the width d ₅ of the widened portion 7a-1
Easy to insert into

In order to fit the warpage preventive member 31 into the slit 7a, the warp preventive member 31 is expanded from the end side where the tapered surface 31a is formed as shown by an arrow R in FIG. Press into the part 7a-1. Thus, the warpage preventing device 31 is firmly fitted into the slit 7a. Although not shown, similarly, a widened portion is formed in the slit 7b, and the warpage preventing tool 31 is fitted therein.

Therefore, for example, when the sheet substrate 1 is heated in a reflow furnace, the printed circuit board 2 is supported by the discarded substrate 3 via the warpage preventing device 31 in the slits 7a and 7b, so that the slits 7a and 7b are long. Also, it is possible to prevent the printed board 2 from being warped at this portion. In addition, by using the warpage preventing tool 31, the number of perforations can be reduced and the work of separating the printed circuit board can be facilitated.

Further, since the warpage preventing tool 31 is firmly fitted and detaches at the same time as the printed circuit board 2 is cut by cutting the perforations, it is difficult to control the strength as in the case where the slit is filled with resin. And it is reusable, which also contributes to the reduction of waste.

Further, a concave portion is formed on the discarded substrate side of the slits 7a and 7b to widen a part of the slit 7a7b and to fit the warpage preventing device 31 into the widened portion. Becomes large and handling becomes easy, and the printed circuit board 2 can be reliably supported.

<Embodiment 4> FIG. 8A is a perspective view of a warpage prevention device according to Embodiment 4 of the present invention, FIG. 8B is a plan view of the warpage prevention device, and FIG. Is I- in FIG.
FIG. 3 is a cross-sectional view taken along line I. FIG. 9A is a plan view showing a state in which the warp preventing device is fitted in a slit.
FIG. 10B is a cross-sectional view taken along line JJ of FIG. Note that the overall configuration of the sheet substrate is the same as that of the first embodiment, and a description and illustration thereof will be omitted.

As shown in FIG. 8, an arc-shaped concave portion 42 is formed on the side of the discard substrate 3 of the slit 7a, whereby a part of the slit 7a is widened. On the other hand, the warpage prevention tool 41 is pin-shaped and circular in plan view. Then, the warp preventing member 41 has a greater width (diameter) d ₁₁ slightly larger than the width d ₁₀ of the widened portion 7a-2 of the slit 7a, and, on one end to form a tapered surface 41a the width (diameter) d ₁₂ of the end face 41b to be smaller than the width d ₁₀ of the widened portion 7a-2 Te,
This facilitates insertion into the widened portion 7a-2.

In order to fit the warpage preventing tool 41 into the slit 7a, as shown by an arrow K in FIG. 8A, the warp preventing tool 41 is expanded from the end side where the tapered surface 41a is formed. Press into part 7a-2. Thus, the warpage prevention tool 41 is firmly fitted into the slit 7a. Although not shown, similarly, a widened portion is formed in the slit 7b, and the warpage preventing tool 41 is fitted.

Therefore, for example, when the sheet substrate 1 is heated in a reflow furnace, the printed circuit board 2 is supported by the discarded substrate 3 via the warpage preventing tool 41 in the slits 7a and 7b, so that the slits 7a and 7b are long. Also, it is possible to prevent the printed board 2 from being warped at this portion. In addition, by using the warpage prevention tool 41, the number of perforations can be reduced and the work of separating the printed circuit board can be facilitated.

Also, since the warpage prevention tool 41 is firmly fitted and detaches at the same time as cutting the perforation to separate the printed circuit board, it is difficult to control the strength as in the case of filling the slit with resin. In addition, since it can be reused, it contributes to reduction of waste.

Also, a concave portion is formed on the discarded substrate side of the slits 7a and 7b to widen a part of the slit 7a7b, and the warpage preventing device 41 is fitted into the widened portion. Becomes large and handling becomes easy, and the printed circuit board 2 can be reliably supported.

<Embodiment 5> FIG. 10A is a perspective view of a warpage preventing device according to Embodiment 5 of the present invention, and FIG.
FIG. 11 is a sectional view taken along line LL of FIG. FIG. 11 is a cross-sectional view showing a state in which the warpage preventing device is fitted in a slit. Note that the overall configuration of the sheet substrate is the same as that of the first embodiment, and a description and illustration thereof will be omitted.

As shown in FIG. 10, a rectangular recess 22 is formed on the side of the discard substrate 3 of the slit 7a, whereby a part of the slit 7a is widened. On the other hand, the warpage prevention tool 51 is provided with a pair of legs 53a and 53b having a spring property (elasticity) on a flange 52. Widening portion 7a of the length d ₁₃ of the flange portion 52 is slit 7a
Than the width d ₅ of -1 is longer, a pair of leg portions 53
a, 53b is slightly wider than the width d ₅ maximum width d ₁₄ is widened parts 7a-1 with widened spacing toward the front end side.

[0052] The pair of leg portions 53a, 53b are bent in the middle, the width d ₁₅ of the tip has become smaller than the width d ₅ of the widened parts 7a-1 of the slit 7a. Note that the bent positions of the legs 53a and 53b are not limited to positions near the distal end as shown in the illustrated example, but may be positions closer to the base end.

In order to fit the warpage preventing tool 51 into the slit 7a, as shown by an arrow M in FIG. 10 (a), the pair of legs 53a, 53b of the warpage preventing tool 41 is connected to the slit 7a.
Into the widened portion 7a-1. Thus, as shown in FIG. 11, the legs 53a, 53b are bent inward (see the arrow P in FIG. 10B), and are firmly fitted into the slits 7a by their spring force. Although not shown, a widened portion is also formed in the slit 7b to similarly
Insert 1

Therefore, for example, when the sheet substrate is heated in a reflow furnace, the printed circuit board 2 is supported by the discarded substrate 3 via the warpage preventing device 51 in the slits 7a and 7b, so that even if the slits 7a and 7b are long, The occurrence of warpage of the printed circuit board 2 at this portion can be prevented. In addition, by using the warpage prevention tool 51, the number of perforations can be reduced and the work of separating the printed circuit board can be facilitated.

Further, since the warpage prevention tool 51 is firmly fitted and is detached at the same time as cutting the perforation to separate the printed circuit board, it is difficult to control the strength as in the case of filling the slit with resin. In addition, since it can be reused, it contributes to reduction of waste. Further, a concave portion is formed on the discarded substrate side of the slits 7a and 7b to widen a part of the slit 7a7b, and the warpage preventing device 51 is fitted into the widened portion. Therefore, the printed circuit board 2 can be reliably supported.

In the above description, a pair of legs 53a, 53b
Is bent from the middle, but is not necessarily limited to this. If the legs 53a and 53b are not bent, the legs 53a and 53b are bent inward and then inserted into the widened portion 7a-1 of the slit 7a. What should I do? In other words,
When the legs 53a and 53b are bent from the middle, the legs 53a and 53b are simply expanded by the widened portion 7a-1 of the slit 7a.
It can be easily fitted simply by pushing it in.

If the collar 52 interferes with the solder print mask, the warpage of the printed circuit board 2 is particularly problematic during reflow, and therefore, for example, after cream solder printing and before reflow, The warpage prevention tool 51 may be mounted together with the electronic component by a mounter (electronic component mounting machine). Since the warpage prevention tool 51 has a collar portion, it can be mounted by a mounter similarly to the electronic component.

<Sixth Embodiment> FIG. 12A is a perspective view of a warp preventing device according to a sixth embodiment of the present invention, and FIG.
FIG. 13 is a sectional view taken along line NN of FIG. Note that the configuration of the sheet substrate is the same as that of the first embodiment, and thus description and illustration thereof are omitted.

As shown in FIG. 12, the warp prevention device 61 is
It has a pin-shaped main body 63 and a flange 62 provided at one end of the main body 63. Main body 63
Is a cylindrical, its width (diameter) d ₁₆ is slit 7a
Width d ₁ of which is equal, it is fitted into the slit 7a. The flange portion 52 has a disk shape and has a width (diameter) d.
₁₇ is larger than the width d ₁ of the slit 7a, the printed circuit board 2 and the discarded substrate surface 2a of the substrate 3 abuts on the 3a.

Then, the warpage preventing member 61 is attached to the sheet substrate 1.
(Eg, a metal such as copper or brass) having a higher coefficient of thermal expansion than the material (eg, glass epoxy resin).

Therefore, as shown in FIG. 12 (b), when the sheet substrate 1 is conveyed to the reflow furnace with the main body 63 of the warpage preventing tool 61 inserted in the slit 7a, the main body 63 is heated by the reflow furnace. Is thermally expanded and firmly fitted into the slit 7a. Although not shown, the warpage preventing tool 61 is similarly fitted into the slit 7a.

Accordingly, since the printed circuit board 2 is supported by the discarded substrate 3 via the warpage preventing member 61 in the slits 7a and 7b, even if the slits 7a and 7b are long, the printed circuit board 2 is warped at these portions. Is prevented. In addition, by using the warpage prevention tool 61, the number of perforations can be reduced and the work of separating the printed circuit board can be facilitated. Further, since the warpage prevention tool 61 is firmly fitted and is detached at the same time as cutting the perforation to separate the printed circuit board, there is no difficulty in strength management as in the case of filling the slit with resin. Since it can be reused, it also contributes to the reduction of waste.

As the material of the warpage preventers 11, 21, 31, 41, 51 of the first to fifth embodiments, glass epoxy resin, metal or the like can be appropriately selected.
In particular, when a material having a larger coefficient of thermal expansion than the material of the sheet substrate 1 is used, the material can be more firmly fitted into the slits 7a and 7b by thermal expansion during heating.

In the above, the case of reflow soldering has been described as an example, but the present invention is not limited to this.
The present invention can be applied to the case of soldering using a dipping bath.

Further, the work of fitting the warp preventing device may be performed manually by an operator or automatically by a device such as a mounter.

[0066]

As described above, according to the embodiment of the present invention, according to the method for preventing warpage of a printed circuit board according to the first invention, even if the slit is long, the warp preventing device is fitted into the slit. Thereby, the warpage of the printed circuit board can be prevented.

Further, according to the printed board warpage preventing method of the second invention, a concave portion is formed on the discard substrate side of the slit to widen a part of the slit, and the warp preventing tool is fitted into the widened portion. As a result, the warpage preventing device becomes larger and handling becomes easier, and the printed circuit board can be reliably supported.

According to the third to tenth aspects of the printed board warpage preventing device, even if the slit is long, the printed board can be prevented from warping by fitting the warpage preventing device into the slit.

Further, by using these warpage preventers, the number of perforations can be reduced and the work of separating the printed circuit board can be facilitated.

Also, since these warpage preventers are firmly fitted by press-fitting or thermal expansion, etc., and easily come off when the printed circuit board is cut off by cutting the perforations.
There is no difficulty in managing the strength as in the case where the slit is filled with resin, and since the slit can be reused, it contributes to the reduction of waste.

[Brief description of the drawings]

FIG. 1 is a plan view of a sheet substrate showing a state in which a warp prevention device according to Embodiment 1 of the present invention is fitted in a slit.

FIG. 2 is a perspective view of the warpage preventing device.

3A is a plan view showing a state in which the warpage preventing device is inserted into a slit, FIG. 3B is a cross-sectional view taken along line AA of FIG. 3A, and FIG. (D) is a cross-sectional view taken along line BB of (c).

FIG. 4 is a perspective view of a warpage prevention device according to Embodiment 2 of the present invention.

5A is a plan view showing a state in which the warpage preventing device is inserted into the slit, and FIG. 5B is a plan view showing a state in which the warpage preventing device is inserted into the slit and rotated.

FIG. 6A is a perspective view of a warpage prevention device according to Embodiment 3 of the present invention, FIG. 6B is a plan view of the warpage prevention device, and FIG.
FIG. 3 is a sectional view taken along line GG of FIG.

FIG. 7A is a plan view showing a state in which the warpage preventing tool is fitted in a slit, and FIG. 7B is a cross-sectional view taken along line HH of FIG.

FIG. 8A is a perspective view of a warpage prevention device according to Embodiment 4 of the present invention, FIG. 8B is a plan view of the warpage prevention device, and FIG.
FIG. 2 is a cross-sectional view taken along line II of FIG.

9A is a plan view showing a state in which the warpage preventing device is fitted in a slit, and FIG. 9B is a cross-sectional view taken along line JJ of FIG. 9A.

FIG. 10A is a perspective view of a warpage preventing device according to Embodiment 5 of the present invention, and FIG. 10B is a cross-sectional view taken along line LL of FIG.

FIG. 11 is a cross-sectional view showing a state in which the warpage preventing device is fitted in a slit.

FIG. 12A is a perspective view of a warpage preventing device according to Embodiment 6 of the present invention, and FIG. 12B is a cross-sectional view taken along line NN of FIG.

FIG. 13 is a plan view illustrating a configuration of a sheet substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet board 2 Printed board 2a, 2b Board surface 3 Discard board 3a, 3b Board surface 7a-7e Slit 7a-1, 7a-2 Widening part 8a-8e Perforation 11, 21, 31, 41, 51, 61 Warpage prevention Tools 12, 63 Body parts 13a, 13b, 52, 62 Collar parts 21a, 21b End faces 22, 42 Depressions 31a, 41a Tapered faces 31b, 41b End faces 53a, 53b Legs

Claims (10)

[Claims] An intermittent slit is formed at a boundary between a printed board and a discarded board, and the printed board is separated from the discarded board by cutting perforations between the slits. A method for preventing warpage of the printed circuit board, wherein the warpage of the printed circuit board is prevented by fitting an anti-warp tool into the slit. Method. 2. The method for preventing warpage of a printed circuit board according to claim 1, wherein a concave portion is formed in the slit on the side of the discarded substrate to partially widen the slit, and the warp preventing device is provided in the widened portion. A method for preventing warpage of a printed circuit board, characterized by being fitted. 3. A printed circuit board having a slit intermittently formed at a boundary between the printed board and the discarded board, wherein the printed board is separated from the discarded board by cutting perforations between the slits. A warp preventing device for preventing warpage of the printed circuit board, wherein the warp of the printed circuit board is configured to be fitted into the slit to prevent warping of the printed circuit board. Protective gear. 4. The device for preventing warpage of a printed circuit board according to claim 3, further comprising a pin-shaped main body, and flanges provided at both ends of the main body, wherein the width of the main body is smaller than that of the slit. At least one of the flanges has a length that is less than or equal to the width of the slit and at least one of the flanges has a length greater than the width of the slit, and is inserted into the slit from one of the flanges. A printed circuit board warpage preventive device, wherein when rotating about an axis, the two brim portions straddle the printed circuit board and the discarded board and come into contact with these board surfaces. 5. The device for preventing warpage of a printed circuit board according to claim 3, wherein the length is set to be slightly larger than the width of the slit and smaller than the width of the slit, and is inserted into the slit. A printed circuit board warpage preventing device characterized in that the printed circuit board is press-fitted into the slit by rotating about an axis. 6. The device for preventing warpage of a printed circuit board according to claim 3, wherein the pin-shaped member has a width slightly larger than the width of the slit, and has one end tapered. A printed circuit board warpage preventing device, wherein a surface is formed and the width of the end face is made smaller than the width of the slit so as to be pressed into the slit from one end side. 7. The printed circuit board warpage preventing device according to claim 3, wherein a pair of leg portions having a spring property is provided on the collar portion, and the collar portion is longer than a width of the slit, and the pair of leg portions has a spring property. The legs are configured such that the interval is widened toward the distal end and the maximum width is slightly wider than the width of the slit, and the pair of legs is press-fitted into the slit while being bent inward. A feature of printed circuit board warpage prevention. 8. The device for preventing warpage of a printed circuit board according to claim 7, wherein the pair of legs are bent from the middle so that the width of the tip is smaller than the width of the slit. A device for preventing warpage of printed circuit boards. 9. The device for preventing warpage of a printed circuit board according to claim 3, comprising: a pin-shaped main body fitted into the slit; and a collar provided at one end of the main body and in contact with a substrate surface. A printed circuit board warpage preventing device, wherein the printed circuit board is formed of a material having a higher coefficient of thermal expansion than the material of the sheet substrate and is firmly fitted into the slit by thermal expansion during heating. 10. The printed board warpage preventing device according to claim 3, wherein the printed board is formed of a material having a higher coefficient of thermal expansion than a material of the sheet substrate, and the thermal expansion during heating is performed. A printed circuit board warpage preventing device characterized in that it is configured to be more firmly fitted into the slit.