JPH02220494A - Electronic component device and manufacture thereof - Google Patents

Abstract

PURPOSE:To enhance a mounting density by a method wherein, out of a plurality of pairs of juxtaposed conductive lands, an area of the front-side conductive land in one direction is made smaller than that of the rear-side conductive land. CONSTITUTION:Out of a plurality of pairs of conductive lands 31, 32 juxtaposed along one direction on a wiring substrate 4, an area of the front-side conductive land 31 in one direction is made smaller than that of the rear-side conductive land 32. Accordingly, a length of the front-side conductive land 31, using a flow soldering method, ln a progress direction of the wiring substrate 4 can be reduced to a length identical to a conductive land using a reflow soldering method. Thereby, a mounting density of an electronic component can be enhanced; a small size and a cost reduction can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electronic component device in which electronic components are mounted on a wiring board such as a printed circuit board or a hybrid integrated circuit board.

(Prior art) Conventionally, as shown in Fig. 3, when a resistor chip or other electronic component C is soldered to a conductive land b of a printed circuit board or a hybrid integrated circuit a by flow soldering, the surface tension of the solder Considering that solder (not shown) does not adhere to conductive land b sufficiently due to the influence of
The area of the conductive land b' shown in Figure 4 to which the electronic component C is soldered by reflow soldering is 1.5 to
It is twice as large.

(Problem to be Solved by the Invention) As described above, the wiring board a of a conventional electronic component device has a conductive land b for flow soldering.
However, since the reflow soldering is larger than the conventional conductive land b', there is a problem that the mounting density of the electronic components C per unit area of the wiring board is low.

An object of the present invention is to solve the problems of the conventional electronic component devices described above.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention solders electronic components to each of a plurality of pairs of conductive lands formed on a wiring board such as a printed circuit board using a flow soldering method. In an electronic component device, a part or all of the plurality of pairs of conductive lands are arranged in parallel along one direction, and a front conductive land in one direction of the juxtaposed conductive lands is arranged as a rear conductive land. The manufacturing method of an electronic component device is characterized by having a smaller area, and in which electronic components are soldered to a plurality of pairs of conductive lands of a wiring board such as a printed circuit board, respectively, by flow soldering. Some or all of the pairs of conductive lands are arranged side by side along one direction, and the front conductive land in one direction of the parallel conductive lands is made smaller in area than the rear conductive land, thereby forming six pairs of conductive lands. Electronic components are placed on the lands, and the wiring board is advanced with the conductive land on the front side in one direction facing forward in the traveling direction, and flow soldering is characterized in that the electronic components are soldered to the pair of conductive lands by a method. shall be.

(Function) When a wiring board is advanced with the small-area conductive land on the front side in the direction of travel, and soldering is performed using the flow soldering method, the molten solder on the conductive land on the front side in the direction of travel will be transferred to the wiring board. The surface tension decreases due to the force caused by the progress of the solder, and as a result, the molten solder adheres to the conductive lands in a widely distributed manner. On the other hand, on the conductive lands on the rear side in the direction of movement of the wiring board, the molten solder is not affected by the force associated with the movement of the wiring board, so the molten solder is not so widely distributed on the conductive lands due to the influence of surface tension. . Therefore, even if the area of the conductive land on the front side in the traveling direction is small, as much solder adheres to the conductive land on the rear side in the traveling direction.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an electronic component device according to an embodiment of the present invention.

In the figure, reference numeral 1 denotes an electronic component such as a multilayer capacitor, and has external electrodes 2 at both ends thereof. 31 and 3
2 are conductive lands formed on the wiring board 4, which is a board, for example.

The area of the conductive land 31 is set to be the size required for reflow soldering, and the area of the conductive land 3□ is set to be the area required for conventional flow soldering. This area is larger than the area of the conductive land 3.

Although not shown in the above-mentioned distribution board 4, there is a
A plurality of pairs of conductive lands 31, 3□ are provided along one direction, and one of the conductive lands 32, 32 arranged in parallel
The conductive land on the front side in the direction has a small area, and the conductive land on the rear side has a large area.

To give an example of the conductive lands 31.32, in conventional flow soldering, the conductive lands using the method are 1.0 fin length apart with a spacing of 1.0+n, but according to the present invention, Conductive land on the front side in the direction of movement of the wiring board 3. The length of reflow soldering is the same as the conductive land using the method <0.8-
It was possible to reduce the length to ■.

This greatly contributes to improving the degree of integration of electronic components on wiring boards in electronic component devices.

To solder the electronic component 1 to the wiring board 4, first place the electronic component 1 so as to straddle the conductive land 31 and temporarily fix it on the wiring board 4 with adhesive, and then solder the electronic component 1 as shown in the second figure. With component 1 on the lower side, conductive land 3 with a smaller area among conductive lands 31 and 3□. is on the front side in the direction of movement of the wiring board 4, and the wiring board 4 is soldered t! 5 along the surface of the jetted molten solder 6.

Thus, both external electrodes 2 of the electronic component 1 are electrically conductive lands 31 .
It is soldered to 32. Note that solder is not shown in FIGS. 1 and 2.

Electronic components include ICs, ) transistors, diodes,
Coils etc. can be applied.

(Effects of the Invention) Since the present invention has the above-described configuration, flow soldering to a wiring board can improve the mounting density of electronic components in an electronic component device in which electronic components are mounted by a method compared to the conventional method. This has the effect of realizing miniaturization and cost reduction.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of an embodiment of the present invention, FIG. 2 is an explanatory diagram of an example of the manufacturing method, and FIG. 3 is a conventional electronic component device using flow soldering. FIG. 4 is a perspective view of a conventional electronic component device using the beam flow soldering method. 1...Electronic component 31.3□...Conductive land 4...Wiring board Fig. 1

Claims (2)

[Claims] 1. In an electronic component device in which electronic components are soldered to a plurality of pairs of conductive lands formed on a wiring board such as a printed circuit board using a flow soldering method, some or all of the plurality of pairs of conductive lands are soldered in one direction. An electronic component device characterized in that a front conductive land in one direction of the juxtaposed conductive lands has a smaller area than a rear conductive land. 2. A method for manufacturing an electronic component device in which electronic components are soldered to a plurality of pairs of conductive lands of a wiring board such as a printed circuit board by a flow soldering method, wherein part or all of the plurality of pairs of conductive lands are soldered in one direction. The area of the front conductive land in one direction of the parallel conductive lands is smaller than that of the rear conductive land, and electronic components are arranged on each pair of conductive lands. A method of manufacturing an electronic component device, comprising advancing a wiring board with the front conductive land facing forward in the direction of travel, and soldering an electronic component to a pair of conductive lands using a flow soldering method.