JPH05110221A - Solder joint structure of circuit parts - Google Patents

Abstract

(57) [Abstract] [Purpose] To obtain a solder joint structure of a circuit component capable of horizontally joining a circuit component on a conductive pattern of a printed circuit board with a predetermined solder thickness. [Structure] A spacer 8 is provided between the printed circuit board 1 and the circuit component 3 and pressed by a spring 6, and the cream solder 4
The circuit component 3 is bonded to the conductive patterns 2a and 2b by a and 4b. [Effect] The predetermined solder thickness t and the horizontal state of the circuit component can be reliably obtained, and the delicate adjustment of the spring is unnecessary.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solder joint structure for a circuit component which is formed by soldering a circuit component on a printed board.

[0002]

2. Description of the Related Art FIG. 8 is a side sectional view showing a conventional solder joint structure of a leadless circuit component, and FIG. 9 is a side sectional view showing a solder joint structure of a circuit component having a lead. Figure 8
1, reference numeral 1 is a printed circuit board, 2a and 2b are conductive patterns such as copper foil provided on the printed circuit board 1, and 3 is a leadless circuit component mechanically and electrically joined to the conductive patterns 2a and 2b. , 4b is cream solder for joining the circuit component 3 and the conductive patterns 2a, 2b, 5 is a supply pipe for supplying the circuit component 3 onto the conductive patterns 2a, 2b, and 6 is for pressing the circuit component 3 on the conductive patterns 2a, 2b It is a spring.

In FIG. 9, reference numeral 7 denotes leads 7a and 7 at both ends.
In the circuit component having b, the leads 7a and 7b are joined to the conductive patterns 2a and 2b by the cream solders 4a and 4b. The supply pipes, springs, etc. are not shown.

Next, the soldering process will be described. In FIG. 8, cream solders 4a and 4b are applied by printing to predetermined joint portions of the conductive patterns 2a and 2b. Next, the supply pipe 5 is moved onto this joint portion to supply the circuit component 3, and then the circuit component 3 is pressed downward by the spring 6 and adhered onto the conductive patterns 2a and 2b. The pressing load of the spring 6 at this time needs to be finely adjusted according to the solder cross section of the joint.

The printed circuit board 1 to which the circuit component 3 is adhered as described above is then put into a heating furnace to melt the cream solders 4a and 4b. Next, the cream solder 4a, 4b is removed from the heating furnace and solidified, so that the circuit component 3 is bonded to the conductive patterns 2a, 2b.

Also in FIG. 9, the circuit component 7 is supplied by the supply pipe and pressed by the spring in exactly the same manner as described above, and then soldering is performed. As prior arts that are similar to the above-mentioned conventional example, there are JP-B-2-19970 and JP-B-23-18870.

[0007]

Since the conventional solder joint structure for circuit parts is constructed as described above, it is very delicate and difficult to adjust the pressing load of the spring 6 when soldering is performed. Therefore, it becomes difficult to attach the circuit components 3 and 7 in a horizontal state, and the circuit component 3 may be inclined and attached as shown in FIGS. 8 and 9.

For this reason, the solder thickness t in FIGS. 8 and 9 cannot be controlled to be constant, and the variation in the solder thickness t becomes large. And circuit parts 3,7
If the inclination of is large, repair work is required. If the solder thickness t is too small, the circuit power is turned ON / OFF.
Due to the temperature change caused by the above, there is a problem that a force may be generated due to a mismatch between the linear expansion coefficients of the conductive patterns 2a and 2b and the circuit components 3 and 7, and the solder joint may be broken.

The present invention has been made in order to solve the above problems, and provides a method for soldering circuit components by which circuit components can always be horizontally bonded with a predetermined solder thickness. It is an object.

[0010]

In the solder joint structure for a circuit component according to the invention of claim 1, a spacer is provided between the circuit component and the printed board or the conductive pattern.

In the solder joint structure for a circuit component according to the second aspect of the present invention, the sphere as the spacer is provided between the circuit component and the conductive pattern.

According to a third aspect of the present invention, there is provided a solder joint structure for a circuit component in which a protrusion is provided on the circuit component, the conductive pattern, or the printed board to form a spacer.

According to a fourth aspect of the present invention, in a solder joint structure for a circuit component, a large number of spheres are placed in advance in cream solder, and the spheres are arranged as spacers between the circuit component and the conductive pattern at the time of joining. To do.

[0014]

In the solder joint structure for circuit parts according to the first to fourth aspects of the present invention, since the spacer is provided, the solder thickness between the circuit part and the conductive pattern is always constant, and the circuit part can be easily placed in a horizontal state. It becomes possible to join.

[0015]

EXAMPLES Example 1. An embodiment of the invention of claim 1 will be described below with reference to the drawings. In FIG. 1, the same parts as those in FIG. In FIG. 1, reference numeral 8 is a spacer made of an insulating material interposed between the lower surface of the circuit component 3 and the upper view of the printed circuit board 1 and having a predetermined thickness.

Next, the operation will be described. Since the spacer 8 is provided, the solder thickness t between the circuit component 3 and the conductive patterns 2a and 2b when pressed by the spring 6 is increased.
Necessarily has a predetermined thickness (for example, 50 to 200 μm), and the circuit component 3 is always mounted in a horizontal state.
Further, the pressing load of the spring 6 does not require delicate adjustment.

Example 2. FIG. 2 shows an embodiment of the invention of claim 2, in which the circuit component 3 and the conductive patterns 2a, 2b are provided.
And a spherical body 9 having a diameter t and made of a conductive material is provided as a spacer. This sphere 9 is a circuit component 3
Four pieces may be provided at the four corners of the lower surface of the.

Example 3. FIG. 3 shows an embodiment of the invention of claim 3, in which a plurality of protrusions 3a as spacers are integrally provided on the lower surface of the circuit component 3, and the conductive patterns 2a, 2
It was brought into contact with b.

Example 4. FIG. 4 shows another embodiment of the invention of claim 3 in which conductive patterns 2a and 2b are integrally provided with protrusions 2c as spacers, respectively, and circuit parts 3
It is the one that is in contact with the lower surface of.

Example 5. FIG. 5 shows another embodiment of the invention of claim 3 in which a protrusion 7c as a spacer is integrally provided on the lower surface of the circuit component 7 having the leads 7a and 7b and brought into contact with the printed circuit board 1. is there.

Example 6. FIG. 6 shows another embodiment of the third aspect of the invention, in which the printed circuit board 1 is integrally provided with the protrusion 1a as a spacer and brought into contact with the lower surface of the circuit component 7.

Example 7. The spacer 8 in FIG.
May be integrally provided with the circuit component 3 or the printed circuit board 1, and the spacer 8 may be used for the circuit component 7.

Example 8. FIG. 7 shows an embodiment of the invention of claim 4, in which a large number of spheres 9 are mixed and placed in advance in the cream solders 4a and 4b.
After applying a and 4b, by pressing the circuit component 3 with the spring 6, some spheres 9 are sandwiched between the circuit component 3 and the conductive patterns 2a and 2b to form spacers. .

According to each of the above-described Examples 2 to 8, the circuit components 3 and 7 can be easily attached in a horizontal state with a predetermined solder thickness t.

[0025]

As described above, according to the first aspect of the invention, the spacer is provided between the circuit component and the printed board or the conductive pattern.

Further, the invention of claim 2 has a structure in which a sphere is provided as the spacer between the circuit component and the conductive pattern.

According to a third aspect of the invention, the spacer is provided with a protrusion integrally with the circuit component, the conductive pattern or the printed board.

According to the invention of claim 4, a solder in which a large number of spheres are mixed in advance is used, and some of the spheres serve as spacers.

Therefore, according to the first to fourth aspects of the present invention, the circuit component can be easily and surely joined to the printed circuit board in a horizontal state with a predetermined solder thickness, whereby the printed circuit board can be joined. It is possible to improve the quality of the upper circuit, and it is also possible to obtain the effect that fine adjustment of the pressing load of the spring is unnecessary.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a solder joint structure of a circuit component according to an embodiment of the invention of claim 1.

FIG. 2 is a side sectional view showing a solder joint structure of a circuit component according to an embodiment of the invention of claim 2;

FIG. 3 is a side sectional view showing a solder joint structure of a circuit component according to an embodiment of the invention of claim 3;

FIG. 4 is a side sectional view showing a solder joint structure of a circuit component according to another embodiment of the invention of claim 3;

FIG. 5 is a side sectional view showing a solder joint structure of a circuit component according to another embodiment of the invention of claim 3;

FIG. 6 is a side sectional view showing a solder joint structure of a circuit component according to another embodiment of the invention of claim 3;

FIG. 7 is a side sectional view showing a solder joint structure of a circuit component according to an embodiment of the invention of claim 4;

FIG. 8 is a side sectional view showing a conventional solder joint structure of a circuit component.

FIG. 9 is a side sectional view showing another example of a conventional solder joint structure for circuit components.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 printed circuit board 1a protrusion 2a, 2b conductive pattern 2c protrusion 3 circuit component 3a protrusion 4a, 4b cream solder (solder) 7 circuit component 7c protrusion 8 spacer 9 sphere

Claims (4)

[Claims] 1. A solder joint structure of a circuit component in which a circuit component is joined to a conductive pattern of a printed circuit board by using solder, wherein a spacer is provided between the circuit component and the printed circuit board or the conductive pattern. Solder joint structure for circuit parts. 2. The solder joint structure for a circuit component according to claim 1, wherein the spacer is a sphere provided between the circuit component and the conductive pattern. 3. The solder joint structure for a circuit component according to claim 1, wherein the spacer is a protrusion integrally provided on the circuit component, the conductive pattern or the printed circuit board. 4. The solder joint structure for a circuit component according to claim 2, wherein the sphere is one of a plurality of spheres mixed in advance in the solder.