JPH07326832A - Wiring board device - Google Patents

Abstract

PURPOSE:To stabilize the ground potential of a circuit board, and reduce the electric contact resistance between a power supply ground pattern and a fixing part member, by stabilizing the state of connection between the power supply ground pattern of a wiring board and the fixing part member. CONSTITUTION:In the connection part between a power supply ground pattern 15 of a wiring board 11 and a fixing part member 12, the surface of the power supply ground pattern 15 formed on the surface of the wiring board 11 whose surface abuts against the fixing part member 12 is coated with a heat resistant solder mask pattern 17 having a plurality of dispersed narrow apertures 18 for exposing the power supply ground pattern 15. A plurality of the narrow apertures 18 are filled with solder wax S. In the connection part between the power supply ground pattern 15 of the wiring board 11 and the fixing part member 12, a plurality of the solder waxes S of small area are dispersed and come into contact with the surface of the fixing part member 12, and the solder wax S comes into contact uniformly with the surface of the fixing part member 12. Hence the connection state of them is stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board device in which a power supply ground pattern formed on a wiring board is electrically connected to a mounting member.

[0002]

2. Description of the Related Art In a wiring board provided in a small electronic device such as a facsimile machine or a printer, it is important to connect a power ground pattern formed on the board to the ground to stabilize the ground potential. This is because connecting the power supply ground pattern of the wiring board to the ground allows the small child device provided with the wiring board to operate stably against electrical external noise such as static electricity, lightning surge, and high frequency noise. Further, it is possible to reduce the amount of electromagnetic radiation emitted by the small electronic device.

For this reason, in providing a conventional wiring board, as shown in FIG.
The configuration shown in FIG. 4 is adopted. 1 in the figure
Is a wiring board on which wiring 9 is formed, 2 is a mounting member 2 for abutting and mounting the wiring board 1, and this mounting member 2 is made of metal. Mounting holes 4 are formed in the wiring board 1, and mounting screw holes 5 are formed in the mounting member 2. The wiring board 1 is brought into contact with the mounting member 2, and the wiring board 1 is mounted by screwing the mounting screw 3 into the mounting hole 4 of the wiring board 1 and then screwing it into the mounting screw hole 5 of the mounting member 2 to tighten the mounting member 2. It is attached to 2.

As shown in FIG. 4A, a power supply ground pattern 6 connected to the wiring 9 is formed on the surface of the wiring board 1 which is in contact with the mounting member 2. As shown in FIG. 4B, this power supply ground pattern 6 has mounting holes 4
It has a circular ring shape. Further, on the surface of the wiring board 1 opposite to the mounting member 2, a circular ring-shaped power supply ground pattern 7 surrounding the mounting hole 4 is formed in the same manner as described above. Reference numeral 8 denotes a heat-resistant solder mask pattern, which is formed on both surfaces of the wiring substrate 1 so as to cover the wiring 9 and covers a portion to which solder solder is not attached at the time of soldering described later. As shown in FIG. 4B, the solder mask pattern 8 is formed so as to surround the power supply ground patterns 6 and 7, so that the entire surfaces of the power supply ground patterns 6 and 7 are exposed.

The power supply ground pattern 6 of the wiring board 1 and the mounting member 2 are joined and electrically connected by soldering using the solder brazing S. The solder brazing S is attached to the entire surface of the power supply ground pattern 6. In addition, the power supply ground pattern 7 of the wiring board 1
And the head 3a of the mounting screw 3 are joined and electrically connected by soldering using the solder brazing S. The solder solder S is attached to the entire surface of the power supply ground pattern 7. This stabilizes the ground potential of the wiring board 1.

The process of attaching the solder brazing to the power supply ground patterns 6 and 7 is carried out by moving the wiring board 1 in a soldering furnace in which the molten solder brazing is stored.

[0007]

However, such a conventional wiring board device has the following problems. That is, when the solder braze S is attached to the power ground pattern 6 of the wiring board 1, the solder braze S is not in a uniform state on the surface of the power ground pattern 6 as shown in FIG. May partially adhere to the power supply ground pattern 6 at a position offset to project like a mountain. In this case, the solder brazing S only partially contacts the surface of the mounting member 2 and does not contact in a uniform state.

For this reason, the connection between the power supply ground pattern 6 and the mounting member 2 is unstable, and as a result, the electrical connection between the two becomes unstable, and the ground potential of the wiring board 1 is not stable. is there. There is also a problem that the electrical contact resistance (impedance) between the power supply ground pattern 6 and the mounting member 2 is high, and electromagnetic radiation is large.

The above-mentioned problem may occur at the contact portion between the power supply ground pattern 7 of the wiring board 1 and the head 3a of the mounting screw 3, but the above-mentioned problem is caused by the power supply ground pattern 6
The influence at the connecting portion between the mounting member 2 and the mounting member 2 is particularly large, and it is desired to solve the problem at this contact portion.

In order to avoid such a problem, after the soldering solder is attached to the wiring board in the soldering furnace, the operator uses the soldering iron to rework the soldering solder attached to the wiring board to a uniform state. Therefore, the productivity of assembling the wiring board becomes very poor.

The present invention has been made in view of the above circumstances, and stabilizes the connection state between the power supply ground pattern and the mounting member on the wiring board to stabilize the ground potential of the wiring board and both. It is an object of the present invention to provide a wiring board device capable of reducing the electrical contact resistance between the wiring boards.

[0012]

In order to achieve the above object, according to the wiring board device of the invention of claim 1, the wiring board and the mounting member made of metal to which the wiring board is attached are attached. A power supply ground pattern is formed on a surface of the wiring board that is in contact with the mounting member, and a solder mask having a plurality of narrow openings dispersed to expose the power supply ground pattern. A pattern is covered, solder solder is filled in the plurality of narrow openings distributed in the solder mask pattern, and the solder solder filled in each of the openings is adhered to the attachment member. Characterize.

According to the wiring board device of the invention of claim 2,
A wiring board; and a mounting member made of metal to which the wiring board is abutted and mounted. A power ground pattern is formed on a surface of the wiring board that abuts the mounting member. A plurality of protrusions are dispersed and formed with a narrow gap between them in a portion that abuts on the substrate, and solder solder is filled and adhered in each of the narrow gaps formed by being dispersed by the protrusions. The solder solder filled and adhered to each of these gaps is bonded to the power supply ground pattern of the wiring board.

[0014]

According to the invention of claim 1, the connecting portion between the wiring board and the mounting member is provided on the surface of the power supply ground pattern formed on the surface of the wiring board that abuts on the mounting member.
Covered with a solder mask pattern having a plurality of narrow apertures distributed to expose this power ground pattern,
Solder solder is filled and adhered to each of a plurality of narrow openings in which the solder mask pattern is dispersed. Therefore, at the connection portion between the wiring board and the mounting member, a plurality of solder solders having small areas are dispersed and contact the surface of the mounting member, and the solder solder contacts the surface of the mounting member in a uniform state.

According to the second aspect of the present invention, in the connecting portion between the wiring board and the mounting member, the connecting portion between the wiring board and the mounting member has a plurality of narrow projections at a portion of the mounting member that abuts on the wiring board. Solder solder is filled and adhered to each of a plurality of narrow gaps formed by being dispersed with a gap therebetween and being dispersed by being sandwiched by these protrusions. Therefore, at the connection portion between the wiring board and the mounting member, a plurality of solder solders having small areas are dispersed and contact the surface of the mounting member, and the solder solder contacts the surface of the mounting member in a uniform state.

That is, when the molten solder solder is attached to a wide area, the solder brazing method is not constant, and when the molten solder solder is adhered to a narrow area, the solder brazing method is constant. Then, the solder brazes are filled in a plurality of dispersed narrow places, and the solder brazes are dispersed in a plurality of small areas. As a result, the solder braze adheres to the entire mating member in a uniform state.

Therefore, according to the first and second aspects of the present invention, the connection state between the power supply ground pattern of the wiring board and the mounting member is stable, and the power supply ground pattern and the mounting member are connected to each other. A current flows over the entire surface of the pattern, the conduction state between the two becomes stable,
The ground potential of the wiring board becomes stable. Further, the electrical contact resistance (impedance) between the two is reduced, and the amount of electromagnetic radiation is reduced.

Further, after the soldering solder is attached to the wiring board in the soldering furnace, it is not necessary for an operator to use the soldering iron to rework the soldering solder attached to the wiring board to a uniform state. The productivity when assembling is very good.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the invention of claim 1 will be described with reference to FIG.

In FIG. 1, 11 is a wiring board, 12 is a mounting member to which the wiring board 11 is mounted, and 13 is a mounting screw which is one means for mounting the wiring base 11 to the mounting member 12.

Although not shown in the drawings, the wiring board 11 has predetermined wirings formed in the same manner as in FIG.
4 is formed so as to penetrate both surfaces. Wiring board 11
A power supply ground pattern 15 connected to the wiring formed on the wiring board 11 is formed on the surface of the wiring board 11 that abuts on the mounting member 12. The power supply ground pattern 15 has a circular ring shape surrounding the mounting hole 14. This shape is because solder solder can be easily applied uniformly and can be easily molded, and the head 3a of the mounting screw 3 is formed.
Has a larger diameter. Further, on the surface of the wiring board 11 opposite to the mounting member 12, a circular annular power-supply ground pattern 16 surrounding the mounting hole 14 is formed in the same manner as described above.

A heat-resistant solder mask pattern 17 is formed on the surface of the wiring board 11 that contacts the mounting member 12. The heat-resistant solder mask pattern 17 is formed on the wiring board 1.
1 is formed with a pattern that covers a portion of the wiring board 11 where the solder solder is not attached.

In the present invention, the heat-resistant solder mask pattern 15 is formed on the surface of the power supply ground pattern 15 of the wiring board 11 in the form described below. That is, FIG.
As shown in (a) to (c), the power supply ground pattern 15
A heat-resistant solder mask pattern 1 having a pattern in which a plurality of slit-shaped openings 18 exposing the power supply ground pattern 15 are arranged in parallel at narrow intervals on the surface of
7 are formed. In other words, the surface of the power supply ground pattern 15 is exposed in a plurality of slits by the slit-shaped openings 18 formed by the heat-resistant solder mask pattern 17. That is, this is an example of the form of the heat-resistant solder mask pattern having a plurality of narrow openings dispersed so as to expose the power ground pattern 15.

The orientation of the plurality of slit-shaped openings 18 is such that the wiring board 1 is passed through a solder furnace to attach solder solder to the wiring board 11 as shown in FIG. 1 (c). It is a direction perpendicular to the moving direction A. This is because the solder solder adheres well. For example, the width T1 of the opening 18 is 2 mm and the width T2 of the space is 2 mm.

As shown in FIG. 1 (a), the wiring board 1
Similarly to the case of the heat-resistant solder mask pattern 15, a plurality of slit-shaped openings 20 are arranged in parallel at narrow intervals on the surface of the power supply ground pattern 16 on the surface opposite to the mounting member 12 in FIG. A heat resistant solder mask pattern 19 is formed.

The mounting member 12 is made of a conductive metal and has a contact portion 1 with which the wiring board 11 is in contact.
2a, and the abutting portion 12a has a mounting screw hole 2
1 is formed. The mounting screw 13 is made of metal.

Then, as shown in FIG. 1A, the wiring board 11 is in contact with the contact portion 12a of the mounting member 12. The mounting screw 13 is a mounting hole 14 of the wiring board 11.
After being passed through the
It is screwed in and tightened. As a result, the wiring board 11 is attached to the attachment member 12.

Further, as shown in FIG. 1A, the power supply ground pattern 15 of the wiring board 11 and the mounting member 12 are joined and electrically connected by soldering using the solder brazing S. The solder brazing S is filled in a plurality of slit-shaped openings 18 formed at a narrow interval by the heat-resistant solder mask pattern 17 covering the power supply ground pattern 15 and exposed to the openings 18. Is attached to. Therefore, the solder brazing S is present in the form of a plurality of slits arranged in parallel at a narrow interval, and the power supply ground pattern 15 and the mounting member 12 are arranged in parallel at a narrow interval. The slit shape is bonded by the solder brazing S.

The power supply ground pattern 16 of the wiring board 11 and the head 13a of the mounting screw 13 are joined and electrically connected by soldering using a solder brazing S. Also here, the solder brazing S is filled in a plurality of slit-shaped openings 20 formed at a narrow interval by the heat-resistant solder mask pattern 19 covering the power supply ground pattern 16 and exposed to these openings 20. It is attached to the ground pattern 16. For this reason,
The power ground pattern 16 and the mounting screw 13 are adhered to each other by a plurality of slit-shaped solder solders S arranged in parallel with a narrow space.

In this way, the ground potential of the wiring board 1 is dropped to the ground via the metal mounting member 12.

In the process of attaching the solder brazing to the power ground patterns 15 and 16, the wiring substrate 1 is moved in a solder furnace in which the molten solder brazing is stored, and the wiring substrate 1 is moved.
This is performed by attaching solder solder to a predetermined portion of the wiring pattern 1 and the surfaces of the power supply ground patterns 15 and 16.

As described above, at the connection portion between the power supply ground pattern 15 of the wiring board 11 and the mounting member 12, the power supply ground pattern 15 formed on the surface of the wiring board 11 that abuts the mounting member 12 has the power supply ground pattern 15 formed thereon. A heat-resistant solder mask pattern 17 having a plurality of dispersed narrow openings 18 exposing the pattern 15 is covered, and the solder solder S is filled and adhered to each of the dispersed narrow openings 18 of the solder mask pattern 17. Therefore, the power supply ground pattern 1 of the wiring board 11
5 and the attachment member 12, the solder braze S having a plurality of small areas is dispersed and comes into contact with the surface of the attachment member 12, so that the solder braze S is evenly attached.
Contact the surface of 2.

Therefore, the connection state between the power supply ground pattern 15 of the wiring board 11 and the mounting member 12 is stable, and a current flows over the entire surface of the power supply ground pattern 15 to stabilize the conduction state. Therefore, the ground potential of the wiring board 11 becomes stable. Further, the electrical contact resistance (impedance) between the two is reduced, and the amount of electromagnetic radiation is reduced.

Further, after the soldering solder is attached to the wiring board 11 in the soldering furnace, it is not necessary for an operator to rework the soldering solder attached to the wiring board to a uniform state using the soldering iron. The productivity of assembling 11 is very good.

An embodiment of the invention of claim 2 will be described with reference to FIG.

The wiring board device of the present invention is different from the wiring board device of the first invention in that the soldering solder is dispersed in the wiring board side structure in the first invention, while the mounting member side is arranged. The difference is that the solder solder is dispersed in the configuration of. Therefore, in FIG. 2, the same parts as those in FIG. 1 are denoted by the same reference numerals, the description thereof will be omitted, and different parts will be described.
The features of the present invention will be described. Figure 1
As shown in (a) to (c), a mounting member 31 having a contact portion 31a that contacts the wiring board 11 is prepared. A plurality of elongated protrusions 32 are formed in parallel at a portion of the contact portion 31a of the mounting member 31 that abuts the power supply ground pattern 15 of the wiring board 11. The slit-shaped gaps 33 are formed in parallel. Each of the gaps 33 is filled with solder solder as described later. That is, this is an example of a form in which a plurality of protrusions are dispersed and formed with a narrow gap therebetween, and a plurality of narrow gaps are dispersed and formed between these protrusions.

The dimension is, for example, that the width t1 of the protrusion 31 is 2
mm, the width t2 of the gap 32 between the protrusions 31 is 2 mm.
The protrusion 32 is formed by, for example, embossing the mounting member 31.

As shown in FIGS. 1A and 1B, the heat-resistant solder mask pattern 15 is formed on the surface of the power supply ground pattern 15 of the wiring board 11. The entire surface of the power supply ground pattern 15 is exposed. is doing. Wiring board 1
The process of attaching the solder solder to the wiring board 1 is
Is placed in a soldering furnace and moved to a predetermined portion of the wiring pattern of the wiring board 11 and the power supply ground pattern 1
This is done by depositing a solder braze on the surface of 5, 16.

Then, as shown in FIG. 1A, the wiring board 11 is mounted on the mounting member 31 by the wiring board 11
Is brought into contact with the mounting portion 31a of the mounting member 31, the mounting screw 13 is passed through the mounting hole 14 of the wiring board 11, and then screwed into the mounting screw hole 35 formed in the mounting member 31 to be tightened.

At the time of this assembly, the power supply ground pattern 15 of the wiring board 11 and the plurality of protrusions 32 of the mounting member 31 are opposed to each other. In this case, the solder brazing S adhered to the power supply ground pattern 15 is dispersed by biting into the plurality of slit-shaped gaps 33 arranged in parallel between the elongated protrusions 32 of the attachment member 31. And is attached to the metallic mounting member 31.

As a result, the power supply ground pattern 15 of the wiring board 11 and the mounting member 12 are adhered by a plurality of slit-shaped solder braces S arranged in parallel with a narrow space. For this reason, the power supply ground pattern 15 of the wiring board 11 and the mounting member 12 are electrically connected, and the ground potential of the wiring board 11 is dropped to the ground via the metal mounting member 12. The ground potential of the wiring board 11 becomes stable.

As described above, according to the present invention, the wiring board 1
The connecting portion between the mounting member 31 and the mounting member 31 is
A plurality of protrusions 3 on the portion of the
2 are dispersed and formed with a narrow gap 33 in between, and solder brazing S is filled and adhered to each of a plurality of narrow gaps 32 formed by being dispersed between these protrusions 31. Therefore, at the connection portion between the wiring board 11 and the mounting member 31, the solder brazing S having a plurality of small areas is dispersed and comes into contact with the surface of the mounting member 31, so that the solder brazing S is evenly formed. Contact the surface.

Therefore, the connection between the ground pattern 15 of the wiring board 11 and the mounting member 31 has a stable connection, and a current flows over the entire surface of the power supply ground pattern to stabilize the conduction. Therefore, the ground potential of the wiring board 11 becomes stable. Further, the electrical contact resistance (impedance) of the connecting portion between the ground pattern 15 of the wiring board 11 and the mounting member 31 is reduced, and the amount of electromagnetic radiation is reduced.

Further, it is not necessary for an operator to use a soldering iron to fix the solder solder adhered to the wiring board to a uniform state after the solder solder is adhered to the wiring board 11 in the solder furnace. The productivity of assembling is very good.

The present invention is not limited to the above-mentioned embodiments, but can be modified in various ways. In the first and second embodiments, the power ground pattern formed on both the surface of the wiring board that contacts the mounting member and the surface on the opposite side of the mounting member in the embodiments is targeted. The target is a connecting portion between the power supply ground pattern formed on the surface that abuts the member and the mounting member. Further, although the wiring board and the mounting member are mounted by tightening the screws in the embodiment, the present invention is not limited to this and other means may be used.

[0046]

As described above, according to the first aspect of the invention, a plurality of dispersed power source ground patterns are exposed on the surface of the power source ground pattern formed on the surface of the wiring board that abuts the mounting member. A solder mask pattern having a narrow opening is covered, and solder solder is filled and attached to each of a plurality of narrow openings in which the solder mask pattern is dispersed. Therefore, at the connection portion between the wiring board and the mounting member, a plurality of solder solders having small areas are dispersed and contact the surface of the mounting member, and the solder solder contacts the surface of the mounting member in a uniform state.

According to the second aspect of the present invention, a plurality of protrusions are dispersedly formed with a narrow gap in a portion of the mounting member that abuts the wiring board, and the protrusions are dispersedly sandwiched with these protrusions. Solder solder is filled and adhered to each of the plurality of narrow gaps. Therefore, at the connection portion between the wiring board and the mounting member, a plurality of solder solders having small areas are dispersed and contact the surface of the mounting member, and the solder solder contacts the surface of the mounting member in a uniform state.

Therefore, according to the first and second aspects of the present invention, the connection between the ground pattern of the wiring board and the mounting member is stable in connection and stable in conduction. Therefore, the ground potential of the wiring board becomes stable. Also, since a current flows over the entire surface of the power ground pattern between the power ground pattern and the mounting member,
The electrical contact resistance (impedance) between the two decreases.

Further, after the soldering solder is attached to the wiring board in the soldering furnace, it is not necessary for the operator to use the soldering iron to rework the soldering solder attached to the wiring board to a uniform state. The productivity to assemble is very good.

[Brief description of drawings]

FIG. 1A is a sectional view showing an apparatus according to an embodiment of the invention of claim 1; (B) is sectional drawing which decomposes | disassembles and shows the apparatus of the same Example. FIG. 6C is a diagram showing a wiring board of the device of the embodiment.

FIG. 2A is a sectional view showing an apparatus according to an embodiment of the invention of claim 2; (B) is sectional drawing which decomposes | disassembles and shows the apparatus of the same Example. (C) is a figure which shows the attachment member of the apparatus of the same Example.

FIG. 3 is an exploded perspective view showing a wiring board and a mounting member.

FIG. 4A is a sectional view showing an example of a conventional device.
FIG. 6B is a diagram showing a wiring board of the device of the same example.

[Explanation of symbols]

11 ... Wiring board, 12 ... Mounting member,
13 ... Mounting screw, 14 ... Mounting hole, 1
5 ... Ground pattern, 16 ... Ground pattern, 17 ... Solder mask pattern, 18 ... Opening, 19
... Solder mask pattern, 31 ... Mounting member, 32
… Protrusions, 33… Gap.

Claims (2)

[Claims] 1. A wiring board, and a mounting member made of metal to which the wiring board is abutted and mounted,
A power supply ground pattern is formed on a surface of the wiring board that is in contact with the mounting member, and a surface of the power supply ground pattern is covered with a solder mask pattern having a plurality of narrow, dispersed openings that expose the power supply ground pattern. Further, solder solder is filled and adhered to each of the plurality of dispersed narrow openings of the solder mask pattern, and the solder solder filled and adhered to each of the openings is adhered to the attachment member. Wiring board device. 2. A wiring board, and a mounting member made of metal to which the wiring board is abutted and mounted.
A power ground pattern is formed on a surface of the wiring board that abuts the mounting member, and a plurality of protrusions are formed in a portion of the mounting member that abuts the wiring board with a narrow gap therebetween. Solder solder is filled and adhered in each of the plurality of narrow gaps formed by being sandwiched between these protrusions and dispersed, and the solder solder filled and adhered in each of these gaps is adhered to the power supply ground pattern of the wiring board. A wiring board device characterized by the above.