JPS61265896A - Multipoint automatic solding apparatus - 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] This invention relates to a soldering device that simultaneously performs multi-point soldering, and is particularly useful for attaching flat type IC lead terminals to a board. This invention relates to an automatic soldering device.

[Summary of the invention]

For example, when soldering a flat type IC to a board, etc., this invention places solder on the tip of a soldering iron that comes into contact with multiple lead terminals of the IC circuit at the same time, and then contacts the soldering iron tip with the lead terminals. By lifting up and moving laterally, a plurality of lead terminals can be soldered to a printed wiring board at the same time.

[Conventional technology]

Methods for soldering electronic components to a board include the solder dip method and the solder reflow method, but the solder dip method requires immersing the electronic components in a jet of solder liquid, so it is difficult to solder flat type ICs. On the other hand, in the solder reflow method, preliminary solder is applied to either the lead terminal of the electronic component or the board, and the electronic component is placed on the board and soldered by heating it. Therefore, it is useful for soldering flat type ICs.

[Problem that the invention seeks to solve]

However, in order to reflow the solder, it is necessary to heat the electronic components to at least the melting point of the solder, which increases the thermal stress on the components and causes failure.
There is also a problem that the reliability of the solder is not high.

It is also possible to perform solder reflow by heating locally with laser or ultrasonic waves, but such equipment is expensive, and solder reflow essentially requires a process to perform preliminary soldering. Therefore, there is a problem of poor work efficiency.

This invention was made to solve these problems, and is an automatic multi-point soldering method that uses the conventional soldering method using a soldering iron tip to perform fine-pitch multi-point soldering reliably and efficiently. The present invention provides a soldering device.

[Means for solving problems]

The multi-point automatic soldering device of the present invention includes a soldering iron tip with a rectangular bottom, a drive unit that can move the iron tip vertically and horizontally, and a predetermined amount of solder applied to the iron tip. The solder supply unit includes a solder supply unit for supplying solder, and a control unit containing a program for controlling movement of the solder tip.

[Effect]

For example, the bottom surface of the iron tip is rectangular so that it can contact multiple lead terminals of a flat type IC at the same time, so a predetermined amount of solder can be placed on this iron tip from the solder supply device. At the same time, by press-contacting the solder placed on the tip of the iron to a plurality of lead terminals coated with flux, the lead terminals and the wiring pattern of the board can be fixed by soldering. In this case, there is a risk that bridging may occur on fine-pit IC boards due to simultaneous soldering, so press the tip of the iron onto the lead terminal and then lift it up slightly.
Furthermore, by controlling the solder to move in the lateral direction, the surface tension of the solder is used to prevent the formation of bridges.

〔Example〕

FIG. 1 is a schematic diagram showing the main parts of the multi-point automatic soldering device of the present invention, in which 1 is a soldering base, 2 is a wiring board positioned horizontally by a soldering base l, and 3 is described later. This iron tip 3 has a flat bottom surface as shown in FIG. Note that the pressurizing and heating section 4 employs the RCC@ structure, which was separately filed by the applicant.1. The tip 3 can be automatically tilted according to the inclination of the contact surface. Reference numeral 5 denotes a drive unit (robot mechanism) that can move the pressurizing and heating unit 4 in the vertical direction and in the X-Y axis direction, and as is well known, it is connected to the arms 5A, 5B, the rotating unit 50, etc. An industrial-grade articulated robot mechanism is used.

The drive section 5 moves the pressurizing and heating section 4 to an arbitrary position on the soldering base 1 according to a programmed command from the control section 6.

Reference numeral 7 denotes a solder supply device for depositing a predetermined amount of solder on the iron tip 3, and 8 denotes a cleaner for cleaning the iron tip 3 with an air jet or a brush. In addition, the pressurizing and heating section 4 is equipped with an electronic section suspension rod 9 that is operated by air or the like.
It is preferable to provide a conveyor 10 for transferring the wiring board 2 in order to integrate the soldering work into the line.

Fig. 2 is a perspective view of the shape of the iron tip 3 viewed from the bottom.The bottom surface 3A of the iron tip 3, which is made of steel or the like, is approximately rectangular, and the - side thereof is a corner cut surface 3B. There is.

As with a soldering iron, this part is preferably plated with hard chrome or the like to improve wetting of the solder.

The operation of the automatic multi-point soldering device of the present invention will be explained below. First, when the electronic components to be soldered are multiple flat type ICs (hereinafter referred to as FPICs), the FPICs are temporarily fixed in a predetermined position on the wiring board 2 coated with high adhesive flux, and then soldered. Place the iron tip 3 at a predetermined position on the base 1, move it into the solder supply device 7, and as shown in FIG.
(Surface) Apply a predetermined amount of solder to 3B. In this case, in order to adhere a certain amount of solder, a device (separately pending application) is used that brings a plurality of solder threads into contact with the iron tip 3 by a certain length.

The control unit 6 has an F installed on the wiring board 2 in advance.
Since the position of the PIC is recorded as data, the drive section 5 is driven by this data to press the iron tip 3 onto the lead terminal of a specific FPIC. Figure 3(a),
(b), (c), (d), and Fig. 4 (a), (b),
(C) and (d) schematically show from the top and side how solder S adheres to the lead terminals of the FPIC, L@-, due to the movement of the iron tip 3. Figure 3 (a) shows the state of the solder S when L and φ are pressed together.
, as shown in FIG. 4(a).

In this state, heat the lead terminals, L, etc. (about 1 second)
Then, most of the solder S, particularly on the cut surface 3B of the iron tip 3, also adheres to the lead terminal side. Then, when the iron tip 3 is slightly lifted (0.3 tsm), most of the melted solder S remains on the lead terminals, L, L, and L.
Some of it remains on tip 3 of the iron (Fig. 3 (b), Fig. 4 (b))
), furthermore, from this state, lead terminal, L, - slow speed (20+) in the forward direction of the fist (arrow direction).
When the iron tip 3 is moved at an angle of sm/S, the lead terminal is bent due to the surface tension of the solder S as shown in FIG. 3(C).

The solder S at intervals of L, . Then, move the iron tip 3 further away from the FPIC and the lead terminal will appear.

The excess solder present in the gaps L, . . . moves to the iron tip 3 side and is separated, completing the soldering of the FPIC and the wiring board 2.

Next, the iron tip 3 is moved to the solder supply device 7 again, and solder is applied to the bottom surface 3A and cut surface 3B of the solder tip 3, and solder is applied to the next FPIC.
Press the lead terminals directly above the terminals L, -, and solder them in the same way.

If the FPIC moves during this soldering operation (along with the movement of the iron tip 3), accurate soldering will not be possible, so it is preferable to press and fix the FPIC with the electronics suspension lever 9. Wiring board 2 with adhesive etc.
It is not necessarily necessary when it is fixed to some extent.

Furthermore, since the excess solder on the iron tip 3 tends to oxidize sequentially, it is preferable to clean the iron tip 3 and remove the excess solder with the cleaner 8 after several to several tens of soldering operations. .

Even if the FPIC has a fine pitch lead spacing of about 0.8 mm, the temperature of the iron tip 3 (270 to 290°
) are controlled constant, and the pressing time of the iron tip 3, the pulling distance,
A bridge-free solder finish can be achieved by controlling the moving speed and the like using data programmed according to the soldering area and the like. Although it is difficult to quantitatively set such data, it can be automated by storing the best data obtained through several tests in the program of the control unit 6.

FIG. 5 is a flow chart of an example of a soldering work program output from the control section 6. The numbers in the program are FPI when soldering different types of IC circuits.
It may be set to a different value each time depending on the size of C and the number of soldered points, and it is preferable that the amount of solder supplied by the solder supply device 7 can be changed at the same time.

Note that, as is well known, the lead terminals of the FPIC may be slightly pre-soldered.

In the above embodiment, a case has been described in which the iron tip 3 is moved by the drive unit 6, but the soldering work can also be performed by moving the wiring board 2.

〔Effect of the invention〕

As explained above, the multi-point automatic soldering device of the present invention can perform electronic components that require multi-point automatic soldering, such as those found in FPIC, in a single soldering operation, and Since the contact time between the electronic component and the electronic component is shortened, the temperature rise of the electronic component is suppressed compared to the one-sided solder reflow method, and it is possible to solder without causing any damage.

Also 1. Since the tip of the iron is automatically driven, fine-pitch planar connections can be made without bridging, and it is also possible to use membrane-based industrial robot mechanisms, reducing equipment costs. It has the advantage of being easier to measure and improving work efficiency.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the main parts of the multi-point automatic soldering device of Hato's invention, Fig. 2 is a perspective view showing the shape of the iron tip, Fig. 3 (
a), (b), (c), (d), and Fig. 4 (a), (
b), (C), and (d) are explanatory diagrams showing the movement of the iron tip and solder from a plane and a side view, and FIG. 5 is a flowchart showing an example of the program. In the figure, 1 is the soldering base, 2 is the wiring board, 3 is the tip of the iron, 4 is the pressure heating part, 5 is the drive part, 6 is the control part, Fig. Figure (d)

Claims (1)

[Claims] A soldering iron tip with a rectangular bottom surface, a solder supply unit that supplies solder to the iron tip, a driving unit that can move the iron tip vertically and horizontally, and a stand that holds an IC board. A multi-point automatic soldering device, comprising a control unit that has a built-in program for controlling movement of the iron tip and can output a signal for driving the drive unit.