JPH0434991A - Method and device for removing foreign substance on circuit board - Google Patents

Abstract

PURPOSE:To remove a foreign substance so that an electrostatic breakdown is not caused in circuit constituent components and so that the foreign substance is not mixed in a circuit and to lower the manufacturing cost of a circuit board by a method wherein a liquid of a prescribed amount is discharged at the tip of a nozzle via the dispenser part of a foreign substance removing device, the liquid made to project and fix by its surface tension is made to abut on the foreign substance and the foreign substance is sucked and removed by a vacuum suction part along with the liquid. CONSTITUTION:Pure water or a liquid, in which an impurity, such as alcohol or the like, is not mixed, is sent out from a liquid feeding device by a prescribed amount for the removal of a solder 4 adhered on the surface of a printed board 1. Whereupon, a liquid 9 is slightly sent out through the tip of a dispenser part 5b and the liquid 9 is made to project in a hemispherical shape from the tip of a nozzle part 5a by its surface tension. Then, the liquid 9 made to project from the tip of the nozzle part 5a is made to abut on the solder 4 adhered on the surface of the board 1 and is sucked by a vacuum pump. The solder 4 is sucked in a vacuum suction part 5c along with the liquid 9. In case the solder 4 is strongly adhered on the board 1, an ultrasonic vibration is applied to the nozzle part 5a and the solder 4 is peeled from the board 1 and thereafter, is sucked up by the vacuum pump.

Description

[Detailed Description of the Invention] Overview A method and apparatus for removing foreign matter from a circuit board, which remove foreign matter such as excess solder attached to a circuit board to prevent electrostatic damage from occurring in circuit components, and to prevent foreign matter from entering the circuit. The purpose of the present invention is to provide a method and apparatus for removing foreign substances from circuit boards, which can be quickly and accurately assembled by preventing foreign substances from occurring on circuit boards, thereby reducing manufacturing costs. A foreign matter removal device for removing foreign matter adhering to a circuit board includes: an elongated cylinder having a nozzle formed at its tip; a cylindrical dispenser section provided within the cylinder for discharging a fixed amount of liquid into the nozzle portion; and the cylinder. A vacuum suction section is provided between the cylindrical dispenser section and the cylinder, and the cylindrical dispenser section is connected to a liquid supply means, and the vacuum suction section is connected to a vacuum suction means.

Industrial applications The present invention relates to a method and apparatus for removing foreign matter from a circuit board.

In recent years, various electronic components such as ICs have been developed, and various mounting techniques have been adopted for the electronic components. By the way, when mounting electronic components on a circuit board such as a printed circuit board, soldering is necessary in most cases, but soldering sometimes causes scattered solder to adhere to the board, and , and other foreign matter may also adhere to it. Such scattered foreign matter such as solder may have a negative effect on circuit operation, so it must be removed. However, since electronic components are often damaged by electrostatic discharge during removal, there is a need for a method for removing foreign substances that does not cause such damage.

BACKGROUND OF THE INVENTION On a printed circuit board on which a desired circuit pattern is formed, an I
When an electronic component such as a C package is soldered, the flux applied to the soldering part gasifies, so air bubbles are generated inside the solder, and the air bubbles burst, causing the solder to scatter. In addition, the solder scattered at t1 becomes small spherical lumps and adheres in large numbers near the leads of the electronic component.

Conventionally, when removing the attached solder or unnecessary foreign matter, it has been removed by pasting it on an adhesive tape, or by using a vacuum suction device, a bottle set, or the like.

Problems to be Solved by the Invention By the way, in the foreign matter removal method described above, since the part from which the solder is removed is made of metal, the metal part may come into contact with the lead of the electronic component or the wiring pattern connected to the lead. Therefore, there are problems in that these parts are damaged due to electrostatic discharge damage, or in the case of adhesive tape, unnecessary foreign matter adhering to the tape may re-enter the circuit formed by the wiring pattern.

Also, if a component is damaged due to electrostatic discharge damage, if the damage is not known during soldering, it will be revealed through testing, and in this case, in order to repair it, you will have to start obtaining parts again. It won't happen. Therefore,
This results in considerable time loss, increases assembly man-hours, and requires additional parts and labor costs, resulting in a problem of increased overall manufacturing costs.

The present invention has been made in view of these points,
By making it possible to remove excess solder and other foreign matter adhering to the circuit board to prevent electrostatic damage to circuit components and to prevent foreign matter from entering the circuit, assembly can be performed quickly and accurately. It is an object of the present invention to provide a method and apparatus for removing foreign substances from a circuit board, which can reduce manufacturing costs.

Means for Solving the Problems A foreign matter removal device that removes foreign matter adhering to a circuit board on which electronic components are mounted includes an elongated cylinder having a nozzle formed at its tip, and the cylinder discharging a fixed amount of liquid into the nozzle portion. a cylindrical dispenser section provided therein, and a vacuum suction section formed between the cylindrical dispenser section and the cylinder, the cylindrical dispenser section being connected to a liquid supply means and the vacuum The suction section is connected to a vacuum suction means.

Then, a predetermined amount of liquid is discharged to the tip of the nozzle through the dispenser part of the foreign object removing device, and the liquid is projected and fixed by surface tension, and this projected and fixed liquid is brought into contact with the foreign object,
The vacuum suction section sucks and removes foreign matter together with the liquid.

According to the present invention, the liquid protruding and fixed at the tip of the nozzle of the foreign object removing device comes into contact with foreign objects attached to the circuit board, and the foreign objects are sucked up together with the liquid. Therefore, the foreign matter removal device
Since the leads of electronic components mounted on the circuit board or the wiring patterns of the board are not directly touched, the electronic components will not be damaged by electrostatic discharge. Further, since only liquid is discharged from the foreign matter removing device and is also sucked, there is no possibility that foreign matter will get mixed in and adhere to the circuit board.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic side view for explaining a method and apparatus for removing foreign matter from a circuit board according to an embodiment of the present invention.

In this figure, 1 is a printed circuit board with a desired wiring pattern formed on both sides, 2 is a ■C package fixed to a predetermined part of the printed circuit board 1 with solder 3, and 4 is a printed circuit board 1 side as explained in the conventional example. It is a small ball of solder attached. 10 is solder 4, 4. This is a foreign matter removal device for removing...

This foreign matter removal group [10] has a pencil shape with a nozzle part 5a at the tip of an elongated cylinder 5, and the inside thereof is as shown in the enlarged cross-sectional view of the nozzle part 5a in FIG.
An elongated cylindrical dispenser part 5b and a dispenser part 5
b and a surrounding vacuum suction section 5c. Further, the dispenser section 5b is directly connected to a first connection pipe 6 (FIG. 1) connected to a liquid supply device (not shown), and the vacuum suction section 5c is connected to a second connection pipe 6 (FIG. 1) connected to a vacuum pump (not shown). It is directly connected to pipe 7. Reference numeral 8 designates the ground of the foreign matter removing device 10.

The foreign matter removal group [210] having such a configuration removes the solder 4, 4, . When removing . As a result, the liquid 9 is slightly sent out from the tip of the dispenser portion 5b as shown by the arrow Y1 in FIG. 2, and the liquid 9 protrudes semispherically from the tip of the nozzle portion 5a due to its surface tension.

Next, as shown in FIG. 1, the liquid 9 protruding from the tip of the nozzle portion 5a is brought into contact with the solder 4 attached to the surface of the printed circuit board 1, and is sucked by a vacuum pump. As a result, the solder 4 and the liquid 9 are sucked into the vacuum suction section 5c in the direction shown by the arrow Y2 in FIG. In addition, if the solder 4 is tightly adhered to the printed circuit board 1, the nozzle part 5a
After applying ultrasonic vibration to peel the half white 4 from the printed circuit board 1, it is sucked up with a vacuum pump. Thereafter, solder 4.4. adhered to one surface of the printed circuit board in the same manner. ... are removed one after another.

Such solder 4,4. According to the removing method, the foreign matter removing device 10 removes the solders 4, 4, . ..., and since static electricity is prevented from accumulating in the foreign matter removal device 10 by the axes 8, electronic components such as the IC package 3 will not be damaged due to electrostatic damage. . Also,
There is no possibility that foreign matter will enter the printed circuit board 1 from the foreign matter removing device 1O when removing the solder 4.

Therefore, the solder 4 or other foreign matter can be quickly removed without damaging the components mounted on the printed circuit board 1, so that the components can be easily removed from damage due to electrostatic discharge as explained in the conventional example. There is no need to start purchasing parts again to repair. As a result, the time loss, increase in assembly man-hours, increases in parts costs and labor costs that have conventionally occurred can be eliminated.

As described in detail, according to the present invention, foreign matter such as excess solder attached to a circuit board can be removed so as not to cause electrostatic damage to circuit components, and at the same time, foreign matter can be removed from the circuit. Since it can be removed without mixing, there is no need to reassemble due to damaged parts, and assembly can be performed quickly and accurately, which has the effect of lowering manufacturing costs.

[Brief explanation of drawings]

FIG. 1 is a schematic side view for explaining a method and apparatus for removing foreign matter from a circuit board according to an embodiment of the present invention, and FIG.
It is an enlarged sectional view of the nozzle part of the foreign matter removal device shown in the figure. 1... Circuit board (printed board), 2... Electronic component <TC package) 4... Foreign object (small spherical solder), 5... Cylinder, 5a... Nozzle, 5b... Dispenser Part, 5c... Vacuum suction part, 9... Liquid, 10... Foreign matter removal device. 1, Print base J 2: IC/G7γ-ji 4:11\Il large solder 5: n- 50, No. 1 5b: Diesbesosu Kano 5c, True! Hit 31 scales! Silk's First Practice, 1st Rank Prisoner Figure 1

Claims (3)

[Claims] 1. In a foreign matter removal device that removes foreign matter (4) attached to a circuit board (1) on which an electronic component (2) is mounted, an elongated cylinder (5) with a nozzle (5a) formed at the tip thereof is used.
and a cylindrical dispenser part (5b) provided in the cylinder (5) for discharging a fixed amount of liquid into the nozzle (5a), and between the cylindrical dispenser part (5b) and the cylinder (5). and a vacuum suction part (5c) formed in the cylindrical dispenser part (5b), and the cylindrical dispenser part (5b) is connected to a liquid supply means, and the vacuum suction part (5c) is connected to the vacuum suction means. foreign matter removal device. 2. A predetermined amount of liquid (9) is applied to the nozzle (5) through the dispenser part (5b) of the foreign matter removing device (5) according to claim 1.
The liquid (9) is discharged to the tip of the liquid (9) and fixed by surface tension, and the liquid (9) that has been fixed in the protruding contact with the foreign object (4), and the vacuum suction part (5c) removes the liquid (9) and the foreign object (4). ) is removed by suction. 3. The method for removing foreign matter from a circuit board according to claim 2, characterized in that the foreign matter (4) is peeled off by applying ultrasonic waves to a nozzle (5a) of the foreign matter removing device (5).