JPH11145576A - Terminal structure of mounting part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a soldered joint between a mounting part and a board in mechanical strength and to lessen the mounting part in mounting area by a method wherein the mounting part is equipped with terminals welded to the board through the intermediary of solder, and the part of the terminal jointed to the board is made reticulate or porous. SOLUTION: An electrode terminal 14 which includes a jointing part 14a jointed to a printed board and is formed of rectangular metal meshes, which are of copper or brass plated for example with nickel, silver, and solder and bent into an L-shape in cross section so as to spread over the sides 2a and 2b of a surface-mounting part 11. The surface-mounting part 11 is mounted on the printed board bringing the jointing parts 14a of the electrode terminals 14 into contact with land pads provided to the printed board, and molten solder is applied to the joining part 14a or the rectangular metal meshes and solidified penetrating into the meshes of metal. Through this setup, a contact area between the jointing parts 14a of the electrode terminal 14 and solder is enlarged to enable only with the jointing parts 14a of the electrode terminals 14 located at the base of the surface-mounting part 1 to realize their soldered joints high in strength for themselves, so that land pads can be reduced in area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal structure of a mounted component, and more particularly to a terminal structure of a mounted component having high reliability of soldering strength and a small mounting area.

[0002]

2. Description of the Related Art Conventionally, when mounting components are mounted on a mounting substrate such as a printed board, a structure is generally used in which electrode terminals of the mounting components are joined to land pads formed on the surface of the mounting substrate using solder. It is a target.

FIG. 4 is a perspective view showing a conventional mounted component. The surface mount component 1 includes side surfaces 2 b, 2 b, which are end faces in a longitudinal direction of a case 2 for storing a component having a predetermined function.
b, an electrode terminal 3 made of a rectangular metal plate protruding outward is provided. These electrode terminals 3, 3 are bent in an L-shaped cross section along the side surface 2b and the main surface 2a. The whole including the joining portions 3a, 3a, which are attachment portions, is disposed so as to straddle the side surface 2b and the main surface 2a.
These electrode terminals 3 are generally formed by plating a surface of a metal plate of copper, brass or the like with nickel, and further performing silver plating or solder plating thereon.

[0004]

By the way, in the conventional surface mount component 1, the joint portion 3 of the electrode terminals 3, 3 is formed.
When soldering a, 3a onto land pads formed on a substrate such as a printed circuit board, sufficient shearing strength against various stresses applied from the outside such as pressing force, bending, impact, and vibration, In order to secure bending strength, impact resistance, vibration resistance, and the like, it is necessary to increase the soldering area as much as possible.

However, in recent years, surface mount components 1
As the size of the soldering area has been reduced and the soldering area has been getting smaller and smaller, it has become difficult to secure a sufficient soldering area.
There has been a problem that it has become difficult to sufficiently secure the reliability of the soldering strength. In addition, in order to form a solder fillet, it is necessary to set the area of the land pad to be slightly larger than the joint portions 3a, 3a of the electrode terminals 3, 3, and there is a problem that the mounting area becomes large.

The present invention has been made in view of the above circumstances, and can improve the reliability of soldering strength.
Moreover, it is an object of the present invention to provide a terminal structure of a mounted component capable of reducing a mounting area.

[0007]

In order to solve the above-mentioned problems, the present invention provides the following terminal structure of a mounted component.
That is, the terminal structure of the mounted component according to claim 1 is a terminal structure of a mounted component having a plurality of terminals bonded to the substrate via solder, and at least a bonding portion of the terminal to the substrate is a mesh. It was done.

According to a second aspect of the present invention, there is provided a terminal structure of a mounted component having a plurality of terminals joined to the substrate via solder, wherein at least a portion of the terminal connected to the substrate is provided with a plurality of terminals. Are formed. The terminal may be arranged so as to straddle a side surface of the mounting component and a main surface on a side facing the substrate.

In the terminal structure of a mounting component according to the first aspect of the present invention, when the terminal is soldered on the substrate, the molten solder enters the mesh of the mesh at the joint portion of the terminal with the substrate. After that, while cooling, the solder solidifies in a state where it enters the mesh. Thereby, the contact area between the terminal and the solder is significantly increased, the actual soldering area is increased, and the solderability therebetween is improved.
Therefore, the soldering strength is increased, and the reliability of the soldering strength is improved. In addition, the bonding strength of the terminal to the substrate can be reduced by the increased soldering strength.

In the terminal structure of a mounting component according to the present invention,
When the terminal is soldered on a substrate, the molten solder enters the plurality of holes at the joint portion of the terminal with the substrate, and then solidifies in a state where the solder enters the plurality of holes during cooling. As a result, the contact area between the terminal and the solder is significantly increased, the actual soldering area is increased, and the solderability between them is improved. Therefore, the soldering strength is increased, and the reliability of the soldering strength is improved. In addition, the bonding strength of the terminal to the substrate can be reduced by the increased soldering strength.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a terminal structure of a mounted component according to the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a surface mount component according to an embodiment of the present invention, FIG. 2 is a side view showing a joint between a terminal of the surface mount component and a substrate, and FIG. 3 is an enlarged sectional view of the joint. In the figure, 11 is a surface mount component, 12 is a printed board (mounting board) on which the surface mount component 11 is mounted, 13
Denotes land pads formed on the printed circuit board 12;
Is an electrode terminal provided on each of the side surfaces 2b and 2b which are end surfaces in the longitudinal direction of the case 2 of the surface mount component 11, and 15 is a solder for joining the electrode terminal 14 and the land pad 13.

These electrode terminals 14 and 14 are bent in an L-shaped cross section along the side surface 2b and the main surface 2a so that the whole including the joint portion 14a with the printed board 12 straddles the side surface 2b and the main surface 2a. It is constituted by a rectangular metal mesh (net-like body). The metal mesh is, for example, copper, brass or the like made of a metal mesh that has been subjected to silver plating or solder plating, or copper, brass or the like has been subjected to nickel plating or the like on the surface of the metal mesh, Further, a material on which silver plating, solder plating, or the like is applied is preferably used.

In the surface mount component 11, the electrode terminals 1
4 and 14 are joined to the printed circuit board 12.
When joining with the solder 15 on the land pad 13 of
The melted solder 15 enters between the meshes of the metal mesh forming the joint portion 14a of the electrode terminal 14, and then solidifies in a state where the solder 15 enters between the meshes of the metal mesh during cooling. Thereby, the contact area between the joint portion 14a of the electrode terminals 14 and 14 and the solder 15 is significantly increased, and the electrode terminal 1 located at the bottom of the surface mount component 11 is formed.
It is possible to perform high-strength soldering only at each of the joining portions 14a of the fourth and fourth joints.

[0015] Further, by improving the solderability,
The soldering strength between the solder 14 and the joint portion 14a of the electrode terminals 14, 14 is significantly increased, and the reliability of the soldering strength is improved. In addition, since the bonding strength 14a of the electrode terminal 14 can be reduced by the increased soldering strength, the area of the land pad 13 can be reduced.

According to the terminal structure of the surface mount component 11 of the present embodiment, the entirety including the joint portion 14a of the electrode terminals 14, 14 extends along the side surface 2b and the main surface 2a so as to straddle the side surface 2b and the main surface 2a. Since it is composed of a rectangular metal mesh bent in an L-shaped cross section, the electrode terminal 14 and the solder 1
The contact area with the electrode 5 can be significantly increased, and soldering with high soldering strength can be performed only at the joint portion 14a of the electrode terminals 14, 14.

Further, since the solderability is improved, the soldering strength between the electrode terminals 14, 14 and the solder 15 can be increased, and the reliability of the soldering strength can be improved. Also, the electrode terminals 1 are increased by the increased soldering strength.
4 can be reduced, the area of the land pad 13 can be reduced, and the mounting area on the printed circuit board 12 can be reduced.

In the terminal structure of the surface-mounted component 11 of the present embodiment, the entire electrode terminal 14 is made of a metal mesh.
The joint 14a may be formed of a metal mesh, and a plurality of holes may be formed in the joint 14a in various arrangements such as a lattice shape and a mesh shape.
Also in this case, the same operation and effect as the terminal structure of the surface mount component 11 of the present embodiment can be achieved.

[0019]

As described above, according to the terminal structure of the mounting component according to the first aspect of the present invention, at least the joint portion of the terminal with the substrate is a mesh, so that the terminal and the solder The contact area between them can be significantly increased, the actual soldering area can be increased, and the solderability between them can be improved. Therefore, the soldering strength between them can be increased, and the reliability of the soldering strength can be improved.

Also, the increased soldering strength makes it possible to reduce the size of the joints between the terminals, thereby reducing the area of land pads and the like on the substrate. Therefore,
The mounting area can be reduced.

According to the terminal structure of the mounting component of the present invention, since a plurality of holes are formed at least in a joint portion of the terminal with the substrate, it is possible to increase a contact area between the terminal and the solder. Thus, the substantial soldering area can be increased, and the solderability between them can be improved. Therefore, the soldering strength between them can be increased, and the reliability of the soldering strength can be improved.

Also, the increased soldering strength makes it possible to reduce the size of the joints between the terminals, thereby reducing the area of land pads and the like on the substrate. Therefore,
The mounting area can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a surface mount component according to an embodiment of the present invention.

FIG. 2 is a side view showing a joint between the terminal of the surface mount component and the substrate according to the embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view showing a joint between a terminal and a substrate of the surface mount component according to one embodiment of the present invention.

FIG. 4 is a perspective view showing a conventional surface mount component.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Surface mount component 2 Case 2a Main surface 2b Side surface 3 Electrode terminal 3a Connection part with printed circuit board 11 Surface mount component 12 Printed circuit board (mounting board) 13 Land pad 14 Electrode terminal 14a Connection part 15 Solder

Claims (3)

[Claims] 1. A terminal structure of a mounting component having a plurality of terminals joined to a substrate via solder, wherein at least a joint portion of the terminal with the substrate is a net-like body. Terminal structure of mounted components. 2. A terminal structure of a mounting component having a plurality of terminals joined to a substrate via solder, wherein a plurality of holes are formed in at least a joint portion of the terminal with the substrate. The terminal structure of the mounted component. 3. The terminal structure for a mounted component according to claim 1, wherein the terminal is arranged so as to straddle a side surface of the mounted component and a main surface on a side facing the substrate.