JPS62238681A - Method of attaching electronic parts to printed wiring board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for mounting electronic components onto printed wiring boards used in various electronic devices, and more specifically,
The present invention relates to a method for mounting a chip-shaped electronic component having a rectangular parallelepiped shape or an electronic component with leads having a rectangular parallelepiped main body and electrodes for external connection.

(Prior Art) A method of mounting this type of electronic component onto a printed wiring board will be explained with reference to FIGS. 4 and 5.

In FIG. 4, the conventional electronic component mounting method is to attach a rectangular parallelepiped with a pair of external connection electrodes 3a and 3b on opposite side walls on an adhesive 2 applied to the surface of a printed wiring board 1. A chip-shaped electronic component 3 and a lead-equipped electronic component 4 having a rectangular parallelepiped main body with at least one external connection electrode piece 4a and 4b on opposing side walls are each placed on a surface 3c of the maximum projected area of the rectangular parallelepiped. and 4
After c is mounted parallel to the above-mentioned printer 1 to wiring board 1,
External connection electrodes 3a and 3b of chip type electronic component 3, connection lands 1a and lb of printed wiring board 1, external connection electrode pieces 4a and 4b of leaded electronic component 4
and connection lands 1c and ld of printed wiring board 1.
and are respectively soldered to form an electronic circuit.6 Note that this mounting method will be referred to as horizontal attachment.

In another example, instead of the adhesive 2 described above, cream solder is applied to the connection lands LA, LB, LC and LD, and after mounting the chip type electronic component 3 and the leaded electronic component 4, There is also an attachment method that involves heating and soldering to form an electronic circuit.

(Problems to be Solved by the Invention) However, since chip-shaped electronic components or electronic components with leads are attached horizontally on a printed wiring board, there is a problem in that the area occupied by the electronic components is large. Furthermore, in FIG. 5, the soldering of the electrodes 3a and 3b for external connection of the horizontally pasted electronic components, the electrode pieces 4a and 4b, and the connection lands la, lb, lc and 1d is performed using the external connection described above. As shown in the connection electrode 3a as a representative, the solders 5 and 6 are moved laterally due to surface tension.
Since it has the characteristic of expanding upward, it is necessary to provide sufficient spacing so that the electrodes 3a or electrode pieces 4a of adjacent electronic components 3 or 4 are not connected by the solder 5. Therefore, the electronic components per area of the printed wiring board 1 There was a problem that the number of attachments decreased.

In order to solve the above-mentioned problems, the present invention provides a method for mounting electronic components onto a printed wiring board, which allows a large number of electronic components to be mounted per area and enables high-density mounting.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides that the surfaces 3C and 4C, which have the largest projected area of the chip-shaped electronic component 3 and the leaded electronic component 4, are connected to the printed wiring board 1. It is installed so that it is perpendicular to the Note that this mounting method will be referred to as vertical mounting.

(Function) Since chip-shaped electronic components with leads and a rectangular parallelepiped main body are attached vertically, the area occupied by the electronic components can be at least the second largest in terms of the projected area of the rectangular parallelepiped.

Therefore, it is possible to mount as many electronic components as the difference between the maximum projected area and the second and subsequent projected areas.

Similarly to FIG. 5 described above, the third diagram exemplarily shows the soldering between the external connection electrode 3a of the vertically attached chip type electronic component 3 and the connection land 1a of the printed wiring board 1.
As shown in the figure, since the external connection electrode 3a is long in the vertical direction, the solder 7 attached to it is affected by gravity and rotates in an open hem with the connection land 1a having the maximum width. Since the object is fixed in a shape similar to that cut in half, the space between the electronic components that was necessary for the solder 5 to become spherical when pasted horizontally is no longer needed, and the mounting density can be improved by that much. can.

(Example) An example of the present invention will be described with reference to FIG. This figure is a perspective view showing a state in which a chip-shaped electronic component 3 and a lead-equipped electronic component 4 are mounted by the electronic component mounting method on a printed wiring board according to the present invention.

In FIG. 1, first, a chip-shaped electronic component 3 and a leaded electronic component are placed on the adhesive 2 applied between the two pairs of connecting lands 1a and 1b and lc and 1d of the printed circuit board 1. After each of the external connection electrodes 3a and 3b and the external connection electrode pieces 4a and 4b of 4 are mounted so that the above connection lands 1a and 1b are connected to lc and ld, the above adhesive 2 is applied. Let it harden and temporarily adhere.

Next, the temporarily bonded printed wiring board 1 is dipped in molten solder, and the external connection electrodes 3a and 3 of the chip-shaped electronic component 3 are
b and connection lands 1a and 1b, external connection electrode pieces 4a and 4b of leaded electronic component 4 and connection land 1
c and 1d are electrically and mechanically connected with solder 7 to form a circuit.

In such a vertical mounting method, compared to the horizontal mounting method shown in FIG. 4, the area required for the printed wiring board 1 is 3. .2X1.6mm2 vs. 3.2X0.6 when attached vertically
mm2, which is reduced to 172 or less, and more electronic components can be mounted by the reduced area.

In addition, in the case of vertical attachment, the electrodes 3a and 3b for external connection or the electrode pieces 4a and 4b, the land la for connection,
The solder 7 connecting lb, lc and ld is the third
As shown in the figure, the connection land 1a has a shape like a half-cut rotary parapet object with the hem at its maximum width, and the fifth
Due to the horizontally attached spherical solder 5 shown in the figure, the distance between adjacent electronic components is required to be 1.25III11.
When attached vertically, the thickness could be reduced to 1.06 mm.

Moreover, the soldering quality was equal to or better than that of the previous one.

Therefore, according to the vertically attached electronic component mounting method, not only the projected area is simply reduced, but also the reduction effect due to the shape of the solder is added, and the mounting density is significantly improved.

In addition, in this embodiment, the chip-shaped electronic component 3 and the leaded electronic component 4, each having a rectangular parallelepiped main body, have been described. Of course, the same effect can be obtained with an electronic component having an octahedral shape 9.

(Effects of the Invention) As explained above, according to the present invention, a rectangular parallelepiped chip-shaped electronic component or a rectangular parallelepiped main body lead-equipped electronic component has a surface having the largest projected area of the rectangular parallelepiped perpendicular to the printed wiring board. By mounting them in such a way, it not only reduces the area occupied on the printed wiring board, but also eliminates the swelling of the connecting solder, making it possible to reduce the distance between adjacent electronic components. The mounting density of components can be greatly improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a printed wiring board on which chip-shaped and leaded electronic components are mounted using the electronic component mounting method on a printed wiring board of the present invention, and FIG. 2 is a perspective view of a polyhedron applied to electronic components. Fig. 3 is a side view of a chip-shaped electronic component soldered using the mounting method according to the present invention, and Fig. 4 is a printed wiring board with chip-shaped electronic components and leaded electronic components mounted using the conventional electronic component mounting method. Perspective view of 5th
The figure is a side view of a chip-shaped component soldered using a conventional mounting method. 1...Printed wiring board, LA, LB, LC. 1d... Connection land, 2... Adhesive, 3.
...Chip type electronic component, 3a, 3b...External connection electrode, 3c, 4c...Maximum projected area surface, 4...
Electronic components with leads, 4a, 4b... electrode pieces for external connection, 5, 6.7... solder. Figure 1 4a4b ---! hfa#H2mv*n Fig. 2 8-10-hedron example Fig. 3 7 --- ↑ Field 4 Ward Fig. 5

Claims (1)

[Claims] A chip-type electronic component equipped with a pair of external connection electrodes on opposite side walls, or a leaded electronic component equipped with at least one external connection electrode piece on opposite side walls, each having a maximum projected area. A method for mounting electronic components onto a printed wiring board, characterized in that the mounting surface is perpendicular to the mounting surface of the printed wiring board.