JP2006041448A - Connection structure of connector and circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connection structure of a connector and a circuit board capable of securing a necessary quantity of a distance Δ1 between an end of a metallic plate in a through hole and an interface of a metal plated layer even when the number of connection terminals of the connector to be mounted on the board having the metallic plate inside increases so that the number of through holes need be increased, preventing a loss in insulation, and improving relative positional accuracy between the connection terminals of the connector and the through holes of the board. <P>SOLUTION: In the connection structure of the connector and the circuit board for solder-connecting the numerous connection terminals 7 of the connector 20 having the terminals 7 with the corresponding through holes 15 provided on the board 1 including the metallic plate 2, insulation layers 3 covering both surfaces of the plate 2 and a circuit 12 provided on the insulation layer 3, the numerous through holes 15 are formed in a hole 4 for the through holes provided on the metallic plate 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a connection structure between a connector having a large number of connection terminals and a circuit board.

In recent years, for example, in the automobile industry, the space for mounting parts on automobiles is approaching the limit, and from the viewpoint of energy saving, demands for miniaturization, weight reduction, and space saving of automobile components are increasing.
Further, miniaturization of the electrical junction box for automobiles is also demanded, and more specifically, for example, miniaturization of a circuit board accommodated in the interior is being studied.

Incidentally, the conventional circuit board is manufactured by a method as shown in FIG.
As shown in FIG. 7A, holes 4 are first drilled at each through-hole formation portion of the metal plate 2 made of, for example, a copper plate or an aluminum plate, which is embedded in the circuit board. Incidentally, the inner diameter of the hole 4 is finally determined in consideration of the size of the through hole formed in this portion.

  Next, as shown in FIG. 7B, both sides of the metal plate 2 are covered with an insulating prepreg, and at the same time, the inside of the hole 4 is also filled with this insulating prepreg, and both sides are finished to be smooth. Is cured to form the insulating layer 3.

Subsequently, as shown in FIG. 7C, the through holes 10 are formed one by one in the holes 4 of the metal plate 2.
Thereafter, as shown in FIG. 7D, the circuit 12 is formed on the insulating layer 3 by printing, for example, and the inner surface of the hole 10 is subjected to metal plating, for example, tin plating to form the metal plating layer 6. The through hole 15 is formed to obtain the circuit board 1.

  FIG. 8 is a partial longitudinal sectional view showing a through-hole forming portion in the conventional circuit board 1 manufactured by the method shown in FIG. FIG. 8 shows a state in which the connector connection terminal 7 is inserted into the through-hole 15 and solder 8 is applied to connect the connector connection terminal 7 to the circuit board 1.

The circuit board 1 has the following problems when the number of connection terminals 7 of the connector to be connected increases.
That is, if the number of connection terminals 7 of the connector to be connected is increased, the number of through holes 15 must be increased correspondingly. In that case, when the circuit board 1 itself is used, for example, for an automobile, simply increasing the number of components and terminals mounted from the viewpoint of the storage space cannot be simply increased.

  Therefore, if the pitch of the through holes 15 (interval between the through holes) is simply reduced, the inner diameter of the holes 4 provided in the metal plate 2 in FIG. 7 and FIG. In that case, the distance Δl between the end portion of the metal plate and the interface of the metal plating layer 6 becomes small, and it becomes difficult to maintain electrical insulation (hereinafter simply referred to as insulation) between the metal plate 2 and the metal plating layer 6. There is a problem. Moreover, it is difficult to accurately form the through hole 10 at the center of the hole 4 provided in advance in the metal plate 2, and the center of the through hole 10 is in any direction with respect to the center of the hole 4. In such a case, the distance Δl between the end portion of the metal plate and the interface of the metal plating layer 6 becomes a smaller value, and there is a problem that the insulating property is impaired.

Also, unlike the case where the connection terminals of separate components are inserted into the numerous through holes 15 of the circuit board 1 and connected, the large number of connecting terminals 7 of the connector whose pitch interval is completely fixed by the housing are passed through. When inserting and connecting to the hole 15, there is a problem that if even one of the through holes 15 has a positional deviation exceeding an allowable range, it is difficult to mount the connector itself, and it is difficult to correct it.
This problem becomes more serious as the number of connection terminals 7 of the connector connected to the circuit board increases.

  Therefore, various methods for solving the above problems were searched. Application of the method disclosed in Patent Document 1 has been studied as one of them. In this method, as shown in FIG. 9, a hole-like bowl-shaped hole 4 is drilled in a through hole formation portion of a metal plate 2 made of a copper plate or an aluminum plate embedded in the circuit board 1, 2 is covered with an insulating material such as an insulating prepreg and the inside of the hole 4 is filled and solidified with the insulating prepreg, and then the hole 4 filled with the insulating layer 3 is filled in this example. Two through-hole holes 10 are formed, and then a printed circuit and a conductive metal plating layer 6 are formed on the insulating layer surfaces on both sides and the inner surface of the through-hole hole 10. This space is filled with an insulating material 11.

JP 2003-243783 A

However, in this method, as can be seen from the fact that the space inside the metal plating layer 6 is filled with the insulating material 11, the through hole disclosed here is for establishing electrical conduction between the inner layers of the multilayer circuit board. However, it is different from a through hole formed on the surface of the circuit board, in which a large number of connection terminals 7 are inserted and fixed by soldering.
Therefore, the hole 4 drilled in the metal plate is provided with at most about four through holes, that is, a type of through hole in which the insulating material 11 is filled in the space inside the metal plating layer 6. However, it does not relate to the through-hole 15 to which a connector having a large number of connection terminals 7, specifically, about 10 connection terminals 7 or more, is connected.

  More specifically, when a connector of a type in which a large number of connection terminals 7 are provided at a predetermined pitch on one connector is collectively inserted into the through hole 15 of the circuit board 1 and soldered, each through It is necessary to accurately position the position including the pitch of the holes 15 according to the position and pitch of the connection terminal 7 on the connector side, but what is disclosed in this Patent Document 1 is nothing about that. I do not teach.

  In view of the above problems, the object of the present invention is to provide an end portion of a metal plate in a through-hole portion even when the number of connection terminals of a connector mounted on a circuit board having a metal plate inside increases to increase the number of through-holes. And a connector that can secure the required amount of distance Δl between the interface of the metal plating layer and the metal plated layer without impairing the insulation property and improving the mutual positional accuracy of the connector connection terminal and the through hole of the circuit board. An object of the present invention is to provide a circuit board connection structure.

  The connector and circuit board connection structure according to claim 1, wherein the connector is provided with a plurality of connection terminals, the metal plate, an insulating layer covering both surfaces of the metal plate, and the insulation. In a connection structure of a connector and a circuit board for solder connection to a corresponding through hole provided in a circuit board having a circuit provided on the layer, a large number of holes are formed in the through hole provided in the metal plate. A through hole is formed.

  According to the circuit board according to claim 1 formed in this way, an elongated hole in which a necessary number of through holes can be formed in the metal plate is provided in advance, and finally in the elongated hole. Since a large number of through-holes, specifically, about 10 or more through-holes are formed, it becomes easy to secure a distance Δl between the end of the metal plate and the interface of the metal plating layer in the through-hole forming portion. . That is, it becomes easier to set Δl to a larger value as compared with the conventional case where one through hole is provided for one hole provided in advance in the metal plate. As a result, it becomes easier to ensure insulation in the through-hole portion.

Also, unlike the case where different parts are connected to each through hole, when the connector to be connected has a large number of connection terminals, the position of the through hole provided on the circuit board matches the position of the connection terminal on the connector side. It must have been done. Even in such a case, according to the connection structure between the connector and the circuit board according to the first aspect, since a large number of through holes are formed in one elongated hole, for example, the pitch of the through holes is set in the column direction. Even if they are different, the target for drilling individual holes is softer than the case of drilling holes with different pitches one by one on a hard metal plate as in the past. In this case, a plurality of through-holes can be formed in a lump using, for example, a punch having a pitch interval accuracy in advance instead of a drill.
Therefore, drilling holes for through holes one by one in a metal plate and drilling holes one by one in the insulating layer filled and solidified in the holes is more efficient than the conventional method of drilling holes in the insulating layer. It is much easier, and it becomes easier to increase the pitch and position accuracy of these holes.

  The connector-circuit board connection structure according to claim 2 of the present invention is the connector-circuit board connection structure according to claim 1, wherein the through hole provided in the metal plate has an oval shape. A large number of through holes are formed in the hole.

According to the connector and circuit board connection structure according to claim 2, the elongated elongated oval hole in which a large number of through holes can be formed inside is formed in advance in the metal plate. By forming a large number of through-holes in the metal plate, the end portion of the metal plate in the through-hole portion is formed as compared with the conventional one in which one through-hole is formed for one through-hole. The distance Δl from the interface of the metal plating layer can be increased. As a result, it becomes easier to ensure insulation in the through-hole portion.
Further, as in the first aspect of the invention, the hole processing for the through hole in the insulating layer is facilitated, and the accuracy of the pitch and position of the holes can be increased.
Moreover, since the shape of the hole is an oval and the inner surface shape of the hole is smooth, stress concentration is unlikely to occur, which is preferable in securing the mechanical strength of the circuit board.

  The connector-circuit board connection structure according to claim 3 of the present invention is the connector-circuit board connection structure according to claim 1, wherein the hole for the through hole provided in the metal plate has a dumpling continuous length. In this form, a large number of through holes are formed in the holes.

According to the connector and circuit board connection structure according to claim 3 thus formed, in addition to the effect of the invention of claim 1 described above, the hole shape is a dumpling-like continuous long shape. A long and narrow hole can be formed in a plate by simply drilling a hole so that adjacent holes partially overlap. That is, unlike the oval hole of the second aspect, it is preferable that the processing time can be shortened because it is not necessary to scrape, for example, the substantially triangular portion 17 shown in FIG.
Moreover, since the appearance of the hole of the drill drilled in the metal plate remains, there is an advantage that the hole processing can be performed while confirming the position when forming the hole for the through hole in the hole.

  As described above, according to the present invention, even when the number of connection terminals of a connector mounted on a circuit board having a metal plate inside increases and the number of through holes must be increased, the end portion of the metal plate in the through hole portion A connector and a circuit board that can secure a necessary distance Δl between the interface of the metal plating layer and the metal plating layer without impairing insulation, and improving the positional accuracy of the connector connection terminal and the through hole of the circuit board. The connection structure can be provided.

  Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a partial perspective view showing an embodiment of a connector / circuit board connection structure according to the present invention. FIG. 2 is an embodiment of the connector / circuit board connection structure according to the present invention housed in an electrical junction box for automobiles. It is a longitudinal cross-sectional view which shows an example.

As shown in FIG. 1, a circuit 12 is formed on insulating layers 3 on both sides of a circuit board 1 having a metal plate 2 therein. Reference numeral 15 denotes a through hole in which the metal plating layer 6 is formed on the inner surface.
The circuit board side terminals 21 of a large number of connection terminals 7 that are now provided in a line in the row direction of the connector 20 are inserted into the numerous through holes 15 provided on the circuit board 1 and the tips thereof are the same as those shown in FIG. And are connected by soldering with a solder 8.
Each connection terminal 7 of the connector 20 has one end inserted into the through-hole 15 and soldered as described above, and the other end is externally connected from the automobile electrical connection box 18 as shown in FIG. The external connection terminal 22 connected to a terminal 31 in, for example, an ECU (Electronic Control Unit) 30 placed on the electrical connection box 18 for an automobile is projected.
Incidentally, the large number of connection terminals 7 extending in the column direction of the connector 20 shown in FIG. 1 are thicker on the left side than on the right side in FIG. 1, and the pitch is also larger.

  In FIG. 1, reference numeral 23 denotes a plastic housing that holds a large number of connection terminals 7, and reference numeral 24 denotes a support member that is formed integrally with the housing 23 at its upper end. Incidentally, the support members 24 are provided at both end portions and an intermediate portion of the connector 20, and fixing portions 25 for fixing the connector 20 to the circuit board 1 are provided at the base end portions of the support members 24 at both end portions. Is formed and is screwed to the circuit board 1 through a screwing hole provided in the fixing portion 25. Of course, it goes without saying that it may be bonded and fixed with an adhesive separately from screwing.

  The intermediate support member 24 may have its lower surface bonded to the circuit board 1 or provided with a small projection, which is fixed by being inserted into a recess or hole provided in advance on the circuit board 1 side. May be. Of course, the connector 20 may be supported with respect to the circuit board 1 without being fixed to the circuit board 1 but simply in contact with the surface of the circuit board 1.

Further, the connecting terminal 7 is formed with a crank portion 26 bent in a crank shape substantially at an intermediate portion thereof. The reason why the connecting portion 7 is provided with the crank portion 26 as described above is that the connector 20 has a large number of connecting terminals 7 as shown in FIG. 1 and is housed as shown in FIG. Since the length of the connection terminal 7 is longer than that of the normal connection terminal because the external connection terminal 22 has to protrude from the connection box 18 to the outside, the connector 20 is connected to the circuit board 1 and fixed. This is because if a large number of terminals 31 are fitted together on the external connection terminal 22 side of the connector 20 at a time, a large fitting pressure is applied to each connection terminal 7.
That is, if the crank part 26 is provided in the intermediate part of the connection terminal 7, the crank part 26 can relieve the stress due to this large fitting pressure, and deformation and damage of the connection terminal 7 can be prevented.

A partial plan view of the through hole 15 provided in the circuit board 1 is shown in FIG.
FIG. 3 is a plan view showing a state where the insulating layer 3 on the surface of the circuit board 1 is peeled off and the surface of the inner metal plate 2 is exposed.
As shown in FIG. 3, an oval hole 4 for a through hole that can form all through holes 15 in which all the connection terminals 7 of the connector 20 are connected to the metal plate 2 in advance is provided with a drill, a polishing machine, etc. In order to match the position and pitch of the connecting terminal 7 of the mating connector 20 to be connected, after filling the inside with an insulating material such as an insulating prepreg and solidifying to form the insulating layer 3, A large number of holes 10 for through holes are collectively formed by punching or the like, and the inner surface of the holes 10 for through holes is subjected to metal plating to form a metal plating layer 6.

Incidentally, as shown in FIG. 3, the left side of the through hole 15 has a larger inner diameter than the right of the through hole 15, and having a pitch P ₁ is larger than P ₂ on the right side of the through hole 15, Figure 1 As shown, in the connection terminal 7 of the connector 20 inserted into the through hole 15 and soldered, more precisely, in the circuit board side terminal 21, the left terminal is thicker than the right terminal and the pitch is larger. Because it is.

4 is also a partial plan view showing a state in which the insulating layer 3 on the surface of the circuit board 1 is peeled and the surface of the inner metal plate 2 is exposed, as in FIG.
The through hole 4 shown in FIG. 4 is characterized by drilling the metal plate 2 so that adjacent drill holes partially overlap each other, and between adjacent holes as shown in FIG. 4 is characterized in that the substantially triangular portion 17 shown in FIG. 4 is not scraped off by a polishing machine or the like.
If the substantially triangular portion 17 is scraped off as shown in FIG. 3, the effect that the shape of the hole 4 becomes smooth and stress concentration hardly occurs on the metal plate 2 can be expected. The dropping requires a considerable processing time, which may lead to an increase in the cost of the circuit board 1. Therefore, the hole 4 for through-holes shown in FIG.

  When the drill hole is used as it is as the elongated hole 4 for the through hole as described above, the appearance of the drill hole drilled in the metal plate 2 remains in addition to the effect that the processing cost can be reduced as described above. Therefore, when the through hole 10 is formed in the hole, it is possible to expect the effect that the position can be easily confirmed and the position of the through hole 10 can be accurately opened.

Next, a procedure for forming such a through hole 15 will be described with reference to FIG. In order to simplify the drawing, the size of the hole 10 is the same.
As shown in FIG. 5 (a), first, a long and narrow hole for a through hole of a dumpling shape or an oval shape is drilled in a through hole forming portion of a metal plate 2 made of a copper plate, an aluminum plate or the like embedded in the circuit board 1. Hole 4 was drilled. When determining the size of the hole 4, the number of through holes 15 formed in the hole 4 and the interface between the end of the metal plate 2 and the metal plating layer 6 in the final through hole part are determined. The size of the hole 4 is determined in consideration of a misalignment that may occur when the through hole 10 is formed in the hole 4 so that a predetermined amount of the distance Δl can be secured.

  As shown in FIG. 5 (b), both sides of the metal plate 2 are covered with an insulating prepreg, and at the same time, the inside of the hole 4 is also filled with the insulating prepreg, and both sides are smoothed, and then the insulating prepreg is cured. Thus, the insulating layer 3 was formed.

Subsequently, as shown in FIG. 5C, the insulating layer 3 in the hole 4 of the metal plate 2 is punched in consideration of the number, size, and pitch of the connecting terminals 7 of the mating connector 20 to be connected. A number of through-holes 10 were formed with good positional accuracy and pitch accuracy.
Thereafter, as shown in FIG. 5 (d), the circuit 12 is formed on the insulating layer 3 by printing, for example, and the inner surface of the hole is subjected to metal plating, for example, tin plating to form the metal plating layer 6. Many holes 15 were formed.
Normally, after the circuit 12 is formed, an insulating resist is provided in a necessary portion, but detailed points are omitted in the drawing.

As described above, an oval or dumpling elongated hole 4 for forming a through hole can be formed in the metal plate 2 previously arranged inside the circuit board, and a large number of through holes 15 can be formed inside the hole 4. Finally, a large number of through-holes 15 could be formed in the holes 4 with high precision by aligning with the connection terminals 7 of the connector to be connected.
When the circuit board side terminals 21 of the connection terminals 7 of the connector 20 were inserted into the through holes 15 on the circuit board 1 side, they could be smoothly inserted without being caught.

  According to the connection structure of the connector and the circuit board of the present invention thus configured, the metal plate 2 does not exist between the adjacent through holes 15 as shown in FIG. 5D, for example. Therefore, for example, the insulation distance Δh from the through hole 15 on the right side in the figure is different from the conventional one in which the hole 4 is formed for each through hole, and the metal plate 2 is between the through holes 15 and 15. Because it doesn't exist, you can get big. That is, insulation is improved. In other words, more through holes can be formed in the limited space of the circuit board 1 in a limited space than the conventional one, and the insulation in the through hole portion is ensured. In addition, the circuit board 1 can be downsized.

  Here, when the shape of the land 16 provided in the through hole 15 is an oval having a long diameter in a direction perpendicular to the arrangement direction of the through holes 15 with respect to the circular through holes 15 as shown in FIG. This is effective when the number of 15 increases and the interval between adjacent through holes 15 must be narrowed.

In the above embodiment, an elongated oval or dumpling hole is adopted as the hole 4 provided in the metal plate 2, but a rectangular hole 4 may be used. However, since the oval is smoother on the inner surface of the hole 4, stress concentration is less likely to occur, and the mechanical strength of the circuit board 1 is not reduced so much. Therefore, the hole 4 is oval rather than rectangular. It is preferable. Further, from the viewpoint of improving the mechanical strength of the circuit board, which is one of the roles of the metal plate 2 in this type of circuit board 1, if the shape of the hole is an elongated oval shape or a dumpling shape, it is not necessary. In addition, the circuit board 1 can be formed without degrading the strength of the circuit board 1.
Further, since it is only necessary to form a smaller number of holes 4 in the metal plate 2 for a large number of through holes 15, compared to the case of forming a single hole 4 for one through hole 15 as in the prior art. Thus, the drilling operation on the metal plate 2 can be shortened, and the manufacturing cost can be reduced.

  As described above, according to the connector and circuit board connection structure of the present invention, even when the number of connection terminals of the connector mounted on the circuit board having a metal plate inside increases and the number of through holes has to be increased, The required amount of distance Δl between the metal plate edge and the metal plating layer interface in the through hole can be secured, without impairing the insulation, and the positional accuracy of the connector connection terminal and the through hole of the circuit board. It is possible to provide a connection structure between a connector and a circuit board that can improve the efficiency.

It is a partial perspective view which shows one Example of the connection structure of the connector and circuit board of this invention. It is a longitudinal cross-sectional view which shows the state which applied the connection structure of the connector of this invention and a circuit board to the electrical junction box for motor vehicles. It is a partial top view which shows the formation state of the through hole concerning this invention. It is a partial top view which shows the formation state of another through hole concerning this invention. It is a partial cross section figure which shows one Example of the formation method of the through hole in the circuit board concerning this invention. It is a partial top view which shows an example of the land shape of the circuit board concerning this invention. It is sectional drawing which shows the formation method of the through hole in the conventional circuit board. It is sectional drawing of the through-hole part of the conventional circuit board. It is a top view which shows the shape of the through hole between the layers of the conventional multilayer circuit board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Circuit board 2 Metal plate 3 Insulation layer 4 Hole for through hole 6 Metal plating layer 7 Connection terminal 12 Circuit 15 Through hole 18 Electrical junction box 20 for automobiles Connector 23 Housing 24 Support member
26 Crank part 30 ECU unit

Claims (3)

  Corresponding through-holes provided in a circuit board having a metal plate, an insulating layer covering both surfaces of the metal plate, and a circuit provided on the insulating layer, in the connector having a plurality of connecting terminals. A connector-circuit board connection structure, wherein a plurality of through-holes are formed in through-holes provided in the metal plate in a solder-connector connector-circuit board connection structure.   2. The connector-circuit board connection structure according to claim 1, wherein the through-holes provided in the metal plate are oblong, and a plurality of through-holes are formed in the holes.   2. The connector and circuit board according to claim 1, wherein the through hole for the through hole provided in the metal plate has a dumpling-like continuous long shape, and a plurality of through holes are formed in the hole. Connection structure.

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