JPH0864917A - Board - Google Patents

Abstract

PURPOSE: To provide a board wherein the generation of a bridge between terminals of an electronic component is prevented, mount position precision of the electronic component can be improved, and board area can be efficiently used. CONSTITUTION: In a board 20 for soldering an electronic component 21, a reference indicating means 46 for positioning used as the reference of positioning at the Line of setting the electronic component 21 serves as a means for storing solder which is arranged in order to prevent the generation of a solder bridge on the terminals of the electronic component, at the time of dipping the terminals in solder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a board for soldering electronic parts.

[0002]

2. Description of the Related Art An electronic component such as a QFP (Quad Flat Package) is soldered to a substrate such as a printed wiring board. As such an electronic component, in addition to QFP, for example, DIP (Dual I
Some have many pins, such as an nline package).

In order to mount a multi-pin electronic component at a predetermined position on a board and solder each pin (terminal) to a predetermined conductor pattern on the board, the board is dipped in solder (DIP).
To do.

As described above, when the multiple pins of the electronic component are electrically connected to the conductor pattern by soldering, a solder bridge may occur between the pins. Therefore, in order to prevent the solder bridge, conventionally, solder pools 2, 3 and 4 are formed on the substrate 1 as shown in FIG. The solder pools 2, 3 and 4 are formed on the substrate 1 corresponding to the three corners of the electronic component 5 such as QFP. That is, the solder pools 2, 3 and 4 are the substrate 1
Are arranged in a direction inclined at an angle of, for example, 45 degrees with respect to the direction in which the solder is dipped in the solder, that is, in the direction in which the solder flows in the pins 6. These solder pools 2, 3, 4
Can guide and store the extra solder of the pin 6 of the electronic component 5, thereby preventing the solder bridge between many pins.

The solder pools 2, 3 and 4 are shown in FIGS.
It has a structure like. FIG. 11 shows AA of FIG.
FIG. 3 is a cross-sectional view taken along the line of FIG.
Is formed. Only the copper foil 8 is formed in a portion surrounded by the resist film 7 in a square shape. This copper foil 8
And the step portions of the resist film 7 are the solder pools 2, 3 and 4.

Further, in the conventional substrate 1, as shown in FIG. 12, when the electronic component 5 such as a QFP is mounted at a predetermined position, in order to improve the position accuracy of the mount, in the vicinity of the electronic component 5, Especially, the alignment marks 8 may be formed at the two corners of the electronic component 5. The alignment mark 8 is shown in an enlarged manner in FIG. 13, and FIG. 14 is a sectional view taken along line BB in FIG. In FIGS. 13 and 14, the copper foil 9 is placed on the substrate 1.
And a resist film 10 is further formed on the copper foil 9 to form a square pattern when viewed from above. A circular mark 8a for alignment is formed in the holes of the copper foil 9 and the resist film 10 only by the copper foil. The mark 8a, the copper foil 9 and the resist film 10
Between them is a space 8b having no copper foil or resist film.

[0007]

As described above, conventionally,
A solder pool is formed on the board in order to prevent bridging between the terminals of the electronic component during the solder dipping operation, or an alignment mark is formed in order to improve the mounting accuracy of the electronic component. However, many electronic components are mounted on a board such as a printed wiring board. Therefore, if the solder pool and the alignment mark are formed separately for each electronic component, the board area can be effectively used. Absent.

Therefore, the present invention has been made in order to solve the above-mentioned problems, and it is possible to prevent the bridge between terminals of an electronic component and simultaneously improve the mounting position accuracy of the electronic component, thereby effectively utilizing the substrate area. The purpose is to provide a substrate.

[0009]

According to the present invention, the above object is to provide a board for soldering electronic parts,
The reference display means for positioning, which serves as a reference for positioning when setting the electronic component, also serves as a means for accumulating solder for preventing a solder bridge from occurring in the terminal of the electronic component when dipping into the solder. This is achieved by the substrate being mounted. In the present invention, preferably, the means for accumulating the solder, which also functions as the reference display means for positioning, is formed so as to be surrounded by the resist layer. In the present invention, preferably, the means for accumulating the solder which also serves as the reference display means for positioning has a conductor part surrounded by the resist layer, and the conductor part is a part for accumulating the solder. is there. In the present invention, preferably, the positioning reference display means of the means for accumulating the solder which also serves as the positioning reference display means is a hole formed in the conductor portion. In the present invention,
Preferably the conductor portion is a copper foil.

[0010]

According to the above structure, the reference display means for positioning also serves as a means for accumulating the solder, so that the accuracy of the mounting position of the electronic component can be improved and the solder bridge can be formed with the minimum board space. It can be prevented. Preferably, a means for accumulating solder also serving as a reference display means for positioning is formed in a portion surrounded by the resist layer, and the means for accumulating the solder does not cause a solder bridge at a pin of the electronic component. Then, guide the excess solder and store it. Preferably, the means for accumulating the solder, which also serves as the reference display means for positioning, has a conductor portion surrounded by the resist layer, and the conductor portion guides and accumulates the excess solder. Preferably, the mount of the electronic component is positioned by the hole formed in the conductor part.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. The examples described below are
Since it is a preferred specific example of the present invention, various technically preferable limitations are attached, but the scope of the present invention is, unless otherwise stated to limit the present invention, in the following description.
It is not limited to these modes.

FIG. 1 shows a preferred embodiment of the substrate of the present invention. FIG. 1 shows a substrate 2 for ease of explanation.
An example in which one electronic component 21 is mounted on 0 is shown. The substrate 20 is, for example, a printed wiring board. In FIG. 1, the substrate 20 on which the electronic component 21 is mounted is
By dipping (DIP) the solder along the direction of the arrow X, the terminals (also referred to as pins or leads) of the electronic component 21 are electrically connected to a predetermined conductor pattern on the substrate 20.

The electronic component 21 is, for example, a QFP having many pins. The electronic component 21 has four corner portions 21a, 21b, 21c, 21d. A large number of pins 6 are provided corresponding to the four sides of the electronic component 21.

FIG. 2 is an enlarged plan view showing the vicinity where the electronic component 21 of FIG. 1 is mounted. Positioning display means 3 corresponding to the two corners 21b and 21d of the electronic component 21 and also serving as means for accumulating solder.
0 and 30 are formed. A normal solder pool 32 is formed corresponding to the other corner portion 21c of the electronic component 21. This solder pool 32 is formed by
It has the same structure as the solder pool shown in.

The means for accumulating the solder and the display means 30 for positioning have a structure as shown in FIGS. 3 and 4. FIG. 3 is a plan view showing the display means 30 for accumulating the solder and positioning shown in FIG. 2, and FIG. 4 is a sectional view taken along the line CC of FIG. A resist layer (also referred to as a resist film) 40 is formed on the substrate 20. Space 4 surrounded by this resist layer 40
2 is, for example, a square as shown in FIG. A copper foil 44 is formed in the space 42. At the center of the copper foil 44, a hole serving as the reference display means 46 is formed.

The stepped portion formed by the copper foil 44 and the resist layer 40 is a means 53 for guiding excess solder and storing solder in order to prevent a solder bridge from occurring between the pins 6 in FIG. is there. That is, means 5 for accumulating solder
Reference numeral 3 denotes a portion for guiding the excess solder by the copper foil 44 so as to prevent a solder bridge from occurring between the pins 6 of the electronic component 21 when the board 20 is dipped in the solder. . The hole is a reference display unit 46 that serves as a reference when positioning the electronic component 21 on the substrate 20.
The positioning reference display means 46 has a circular shape when viewed from above in the embodiments shown in FIGS.

In addition, the resist layer 4 shown in FIG.
0 and the substrate 20 and a predetermined conductor pattern 5 for circuit wiring
0 is formed. As described above, the display means for positioning and the means for accumulating the solder, which are conventionally formed separately, are formed at the common position in the embodiment of the present invention.

By using the means for accumulating the solder and the reference display means for positioning as well, the area of the substrate can be effectively used. In particular, the present invention is particularly effective in that the substrate area is effectively used when a large number of electronic components are mounted on the substrate.

FIG. 5 shows an example of a reference display means 90 for positioning and also serving as a means for accumulating another type of solder different from the embodiment of the present invention shown in FIG. Similarly, FIG. 6 shows a reference display means 10 for storing solder and also for positioning.
0, and FIG. 7 shows a reference display means 110 for positioning and positioning another solder.
In the embodiment of FIG. 5, the resist layer 94 and the copper foil 44 form means 92 for accumulating the square solder.
The reference display means 96 for positioning is formed in a rectangular or square shape.

In the embodiment shown in FIG. 6, the resist layer 104 and the copper foil 44 have means 102 for accumulating solder and reference display means 106 for positioning, which are concentric circles. . A copper foil 44 is formed in the means 102 for storing solder. In the embodiment of FIG. 7, unlike the case of FIG. 6, the reference display means 116 for positioning is a square or a rectangle. Other than that is the same as the embodiment of FIG.

As the substrate, for example, a paper base epoxy resin substrate, a synthetic fiber cloth base epoxy resin, a glass cloth base epoxy resin, a paper base phenol resin or glass cloth, a paper composite base epoxy resin glass cloth, glass. A non-woven composite base material such as epoxy resin or ceramic can be adopted. The resist layer is a commonly used acid resistant material.

FIG. 8 shows another embodiment of the present invention. The electronic component 61 in FIG. 8 is a DIP. Corresponding to the two corners 61a and 61b of the electronic component 61, reference display means 70, 70 for storing two solders and also for positioning are formed on the substrate 60. The means for accumulating the solder and the reference display means 70 for positioning have the same structure as the means for accumulating the solder and reference display means 30 for the positioning in FIG.

The present invention is not limited to the above embodiment. In the above-described embodiment, the means for accumulating solder and the reference display means for positioning are formed by using a square or circular pattern, but not limited to this, a triangle or a pentagon or more, an ellipse, a rhombus, Heart shape and other shapes can be adopted. In addition to the multi-pin ICs such as QFP and DIP, the present invention is an electronic component,
It is also possible to apply it when mounting chip components on a substrate. The chip component is, for example, a rectangular or cylindrical resistor, capacitor, transistor or the like.

[0024]

As described above, according to the present invention, it is possible to prevent the bridge between the terminals of the electronic component, improve the mount position accuracy of the electronic component at the same time, and provide a substrate which can effectively utilize the substrate area. be able to.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a board provided with a means for accumulating solder according to the present invention and a reference display means for positioning.

FIG. 2 is a plan view showing the electronic component of FIG. 1 and a means for accumulating solder and a reference display means for positioning.

FIG. 3 is an enlarged view showing a unit for accumulating solder and a reference display unit for positioning shown in FIG. 2;

4 is a cross-sectional view taken along the line CC of FIG.

FIG. 5 is a diagram showing another embodiment of the means for accumulating solder and the reference display means for positioning of the present invention.

FIG. 6 is a view showing another embodiment of the means for accumulating solder and the positioning reference display means of the present invention.

FIG. 7 is a view showing another embodiment of the means for accumulating solder and the positioning reference display means of the present invention.

FIG. 8 is a diagram showing an example in which another embodiment of the means for accumulating solder and the positioning reference display means of the present invention is applied to a DIP.

FIG. 9 is a plan view showing a conventional solder pool pattern and an electronic component.

FIG. 10 is an enlarged view showing the solder pool in FIG. 9;

11 is a cross-sectional view taken along the line AA of FIG.

FIG. 12 is a view showing an example of a conventional alignment mark of an electronic component and the electronic component.

13 is a plan view showing the alignment mark of FIG.

14 is a cross-sectional view taken along the line BB of FIG.

[Explanation of symbols]

20 Substrate 21 Electronic Components 21b, 21d Corners of Electronic Components 30 Means for Retaining Solder and Displaying Means for Positioning 40 Resist Film 42 Means for Retaining Solder 44 Copper Foil (Conductor) 46 Displaying Means for Positioning 53 Means for collecting solder

Claims (5)

[Claims] 1. A board for soldering an electronic component, wherein a reference display means for positioning, which serves as a reference for positioning when setting the electronic component, has a solder bridge on a terminal of the electronic component when dipping into solder. A substrate which also functions as a means for accumulating solder for preventing the occurrence of soldering. 2. A method for surrounding a resist layer,
The board according to claim 1, wherein means for accumulating the solder, which also functions as the reference display means for positioning, is formed. 3. The means for accumulating solder, which also serves as the reference display means for positioning, has a conductor portion surrounded by the resist layer, and the conductor portion is a portion for accumulating the solder. Board. 4. The positioning reference display means of the means for accumulating the solder which also serves as the positioning reference display means is a hole formed in the conductor portion.
The substrate according to. 5. The substrate according to claim 3, wherein the conductor portion is a copper foil.