JPH01237073A - Method and device for removing defective solder - Google Patents

Abstract

PURPOSE:To facilitate the repairing of soldering and to improve the workability by pressing a sucking wire to the defective solder of the above of a printed board, melting the defective solder by the molten solder in a small quantity and removing it by sucking with the capillarity of the sucking wire. CONSTITUTION:A manual defective solder removing device 1 is composed of a soldering iron main body 2, sucking wire feeding unit 4 and string solder feeding unit 7. The soldering iron main body 2 has a heater part 5 at the upper part and the winding roll 10 of a flux cored string solder 9 is arranged at the rear part of the heater part 5. On the other hand, a sucking wire feeding unit 4 is integrally provided at the lower end part of the string solder feeding unit 7. And the sucking wire 3 is mounted on a defective solder and the string solder is delivered simultaneously with pressing a solder iron tip 6 onto the sucking wire 3. Then, the string solder 9 is melted a bit and the defective solder is melted at once with the heat from the soldering iron tip 6 being transferred via the sucking wire 3. The molten defective solder is absorbed to the sucking wire 3 by the capillarity and a correct soldering is executed once again.

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a method and apparatus for removing defective solder.

<Conventional technology> Electronic components (such as ICs and resistors) are mounted on the printed circuit board.
The pins are attached by soldering. Although this soldering work is performed manually by a worker, and automatic soldering is performed by a machine using a device, defects in the solder inevitably occur.

Conventionally, such defective solder is removed by first melting the defective solder and then removing the melted defective solder using a vacuum.

<Problems to be Solved by the Invention> However, in such conventional vacuum-type removal methods, melted defective solder easily solidifies, so it quickly solidifies and becomes clogged in the vacuum mechanism, making work difficult. There were problems with reliability and maintenance.

The present invention has been made by paying attention to such conventional technology, and aims to provide a method and apparatus for removing defective solder that can reliably remove defective solder.

Means for Solving the Problems> In order to achieve the above object, the method and device for removing defective solder according to the present invention reliably remove molten defective solder by utilizing the capillary action of a blotting wire. That is.

Specifically, a blotting wire is pressed against the defective solder on the printed circuit board, and while a small amount of molten solder is applied to the blotting wire, the defective solder is heated with JJI+ to melt it, and the molten defective solder is removed by the blotting wire. It is designed to remove by blotting using capillary phenomenon (first invention).

As a manual device for removing the defective solder, a soldering iron body having a soldering iron tip at the tip is integrally provided with a suction wire supply unit that can freely supply suction wire to the tip of the soldering iron tip. A device for removing defective solder (second invention), a soldering iron body having a soldering iron tip at its tip, a suction wire supply unit capable of freely supplying a suction wire to the tip of the soldering iron tip; A defective solder removal device (third invention) characterized in that it is integrally provided with a thread solder supply unit that can freely supply thread solder to the tip, and a soldering iron body having a soldering iron tip at the tip. , a suction wire supply unit capable of freely supplying a suction wire to the tip of the soldering iron tip and equipped with a suction wire cutter mechanism for cutting the supplied suction wire; and a thread solder supply capable of freely supplying thread solder to the tip of the soldering iron tip. A defective solder removal device (fourth
invention) and.

Furthermore, as an automatic device for removing the defective solder mentioned above, the head of a robot arm that can be moved to any position and rotated freely removes the defective solder that is fixed to the pin on the printed circuit board while holding the suction wire. A fifth invention is provided in which a set finger unit for pressing and a soldering iron unit for applying heat treatment to the defective solder are assembled.

<Function> After pressing a blotting wire against the defective solder, if a small amount of molten solder is applied to the blotting wire and heat treatment is applied to the defective solder using a soldering iron or a laser beam, the defective solder will be melted. At the same time as it melts, it is sucked up to the suction wire by capillary action. The molten defective solder has a large surface tension and is reliably and completely absorbed by the blotting wire (Also, since a small amount of molten solder is applied to the blotting wire,
This small amount of molten solder becomes "water", increasing the heat transfer efficiency of the blotting wire, and the heat is directly transmitted to the defective solder, making it easier to melt the defective solder.
Melted defective solder is easily absorbed by the blotting wire.

Embodiments Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

1 to 3 (a), (b), and (c) are diagrams showing a manual defective solder removal device which is an embodiment of the present invention. This manual defective solder removal device 1 mainly includes a pistol-shaped soldering iron main body 2, a blotting wire supply unit 4 capable of freely supplying a blotting wire 3, and a thread solder supply unit 7.

The soldering iron main body 2 has a heater section 5 at the top, and a curved iron tip 6 is provided at the tip of the heater section 5. Further, a guide tube 8 extending toward the tip of the soldering iron tip 6 is attached to the tip of the thread solder supply unit 7 that fixes the heater section 5 . At the rear of the heater section 5 is a winding roll 1 wrapped with flux-cored solder thread 9.
0 is arranged, and the thread solder 9 is supplied to the thread solder supply unit 7.
The guide tube 8 can be fed from the tip of the guide tube 8 through the inside thereof and held between a pair of delivery rollers 11 .

On the other hand, a suction wire supply unit 4 is integrally provided at the lower end of the thread solder supply unit 7. At the bottom of the blotting wire supply unit 4, a winding roll 12 is arranged, around which a band-shaped blotting wire 3 made of braided thin steel wire is wound.The blotting wire 3 is passed through the inside of the blotting wire supply unit 4. While being held between a pair of delivery rollers 13, it can be supplied to the tip of the soldering iron tip 6 from a guide tube 14 protruding from the tip, similar to the thread solder 9. Although it is difficult to see in the drawing, two switch buttons 15 are arranged in parallel on the thread solder supply unit 7, and by pressing the switch buttons 15,
A fixed amount of solder thread 9 and suction wire 3 can be supplied. Further, the soldering iron tip 6 of the heater section 5 is heated when the power cord 16 at the end of the thread solder supply unit 7 is connected to a power source.

Furthermore, the blotting wire supply unit 4 is provided with a blotting wire cutter mechanism 50. That is,
A nail clipper-shaped cutter body 52 is fixed with the blade edge 51 facing the tip of the guide tube 14, and a bevelled piston 54 is pressed against the stepped portion 53 of the cutter body 52 to close the blade edge 51. A cylinder 55 is provided.

Next, how to use this manual defective solder removal device 1 will be explained [see FIGS. 3(a), (b), and (C)].

Reference numeral 17 denotes a printed circuit board, to which pins 19 of an electronic component ICl3 are soldered with protrusions on the other side. Although the solder fixing this pin 19 is not shown in the drawing, it is defective solder 20 that has caused a bridge (a phenomenon in which solder and solder connect) with an adjacent pin. Then, the suction wire 3 supplied from the thread solder supply unit 7 is placed on this defective solder 20. Then, the soldering iron tip 6 of the manual defective solder removal device 1 is pressed onto the suction wire 3, and at the same time, the thread solder 9 is sent out to the soldering iron tip 6 (see Fig. 3).
See a)]. By doing so, the thread solder 9 is slightly melted at the soldering iron tip 6 and absorbed by the suction wire 3. The heat from the soldering iron tip 6 is transmitted to the defective solder 20 via the suction wire 3, so that the defective solder 20 melts immediately. The melted defective solder 20 is absorbed by the suction wire 3 by capillary action [see FIG. 3(b)]. After the poorly melted solder 20 is absorbed by the suction wire 3, nothing remains. Then, press the switch of the blotting wire cutter mechanism 50 (not shown),
Protruding the barrel-shaped piston 54 and closing the cutting edge 51,
The tip of the blotting wire 3 that has absorbed the defective solder 20 is cut off (see FIG. 3(C)), and the next removal operation can be performed using the tip of the new blotting wire 3.

The manual defective solder removal device 1 according to this embodiment not only removes the defective solder 20 as described above (but also can perform accurate soldering again after removing the defective solder 20). In other words, the pin 19 can be soldered by pressing the iron tip 6 against the pin 19 and supplying only the thread solder 9. Therefore, if defective solder 20 occurs, With this manual defective solder removal device 1, defective solder 20 can be removed and re-soldering can be performed.

4 to 7 (a), (b), and (C) are diagrams showing an automatic defective solder removal device that is another embodiment of the present invention.

Note that the same reference numerals are given to the parts supplied as in the previous embodiment, and redundant explanation will be omitted.

The automatic defective solder removal device 21 according to this embodiment has a defective solder removal device 21 in which a pin 19 is fixed on a printed circuit board 17 while holding a suction wire 23 to a head 22 of a robot arm that can move to any position and freely rotate. This assembly includes a cent finger unit 24 that faces the solder 20 and a soldering iron unit 25 that applies heat treatment to the defective solder 20. The set finger unit 24 and the soldering iron unit 25 each have cylinders 26 and 27 that allow the finger part 28 and the soldering iron part 29 to be moved up and down independently. It is slanted in a V-shape with the center at the center. Further, numeral 30 denotes a suction wire supply device, which sequentially supplies suction wires 23 of a fixed length size, and is disposed on the side of the stage 31 on which the printed circuit board 17 is fixed.

Further, this automatic defective solder removal device 21 is electrically connected to an automatic solder inspection device (not shown), and is automatically moved to the position of defective solder 20 determined to be “defective” based on a signal from the automatic solder inspection device. It is designed to be able to be positioned and moved.

The finger portion 28 of the set finger unit 24 that is vertically movable is provided with a pair of left and right claw bodies 34 that can open and close the toe 33 at the center of the shaft 32. That is, when the tip of the barrel-shaped piston 35 is inserted between the upper ends of the claw body 34, the claw 33 opens, and when it is removed, the claw 33 is closed by a certain biasing force of a spring (not shown).

Therefore, the suction wire 23 of a certain length can be held and held between the toes 33.

The iron portion 29 of the soldering iron unit 25 is provided with a soldering iron tip 36 at the tip thereof, and is also provided with a guide tube 37 that can freely supply thread solder 9 to be fluxed toward the tip of the soldering iron tip 36. .

This guide tube 37 is connected to a thread solder supply device (not shown) to supply a fixed amount of thread solder 9.

The blotting wire supply device 30 is equipped with a take-up roll 38 around which the blotting wire 23 is wound, a delivery roller 39 that sends out a certain amount of the blotting wire 23, and a pair of upper and lower cutters 40 [FIG. reference〕.

Then, the suction wire 2 is wound around the take-up roll 38.
3 is made to protrude from the outlet by a certain amount by a delivery roller 39, and the set finger unit 24 moved by the head 22 of the robot arm picks up this suction wire 23.
When the user comes to grab the wire, the wire is cut with a cutter 40, and the suction wire 23 having a length of -100 mm can be passed to the set finger unit 24.

Next, a method of using this automatic defective solder removal device 21 will be explained (see FIG. 7(a) and (C)).

First, the head 22 of the robot arm moves the set finger unit 24 and the soldering iron unit 25 above the suction wire supply device 3o (hyperactively), and the toe 33 of the set finger unit 24 suctions a certain length. Grasp the wire 23. Then, by a signal from an automatic inspection device (not shown), the set finger unit 2
4 and the soldering iron unit 25 are brought above the printed circuit board 17 and positioned above the bottle 19 fixed with the defective solder 20 to be worked on. Then, the iron part 29 and the finger part 28 are each lowered along the inclination direction using the cylinders 26 and 27. Then, the blotting wire 23 is placed on the defective solder 20, and the soldering iron tip 3G is pressed onto the blotting wire 23, and at the same time, a small amount of thread solder 9 is sent out toward the soldering iron tip 36 [see FIG. 7(a)] ]. By doing so, the thread solder 9 is slightly melted at the soldering iron tip 36 and absorbed by the suction wire 23. The heat from the soldering iron tip 36 is transmitted to the defective solder 20 via the suction wire 23, so that the defective solder 20 melts immediately.

The melted defective solder 20 is removed by the suction wire 2 due to capillary action.
3 [see Figure 7(b)].

After absorbing the melted defective solder 20 with the suction wire 23, the set finger unit 24 and the soldering iron unit 25 are moved upward, and then only the soldering iron unit 25 is lowered again, and the defective solder 20 is removed.
By pressing the soldering iron tip 36 onto the pin 19 after removing the pin 19 and supplying only the thread solder 9, soldering of the bottle 19 is completed.
"Redo" [see Figure 7(C)].

When this "redo" of soldering is completed, the soldering iron unit 25 and the set finger unit 24 are each moved greatly by the movement of the head 22 of the robot arm, and the suction wire 2 that has absorbed the defective solder 20 is moved.
Discard 3 in place. Then, in response to the next signal from the automatic solder inspection device, the above-mentioned operation is repeated for another defective solder, and all the defective solders 20 on the printed circuit board 17 can be sequentially redone.

In the above explanation, only heating with a soldering iron was used as an example of "heat treatment", but irradiation heating with a YAG laser beam etc. may also be used. However, the present invention is not limited to this, and regarding the automatic defective solder removal device 21, the suction wire may be supplied by a separate type suction wire supply device 30 as in the above embodiment. However, the suction wire supply mechanism may be attached to the cent finger unit 24 itself.

Effects> Since the method and device for removing defective solder according to the present invention have the contents as explained above, even if defective solder that has failed in soldering occurs, it is possible to easily and reliably remove the defective solder. Therefore, it is possible to easily "redo" soldering, and the overall workability of soldering can be improved.

In addition, as shown in the example, soldering is not only capable of removing defective solder (but can also be equipped with other functions), so soldering is highly versatile in work, and can be used with automatic solder inspection equipment, etc. By combining these methods, it is possible to automatically "redo" defective solder.

Furthermore, since defective solder is removed using the physical phenomenon of capillarity of the blotting wire, there are fewer troubles in the removal work and it is advantageous in terms of maintenance.

[Brief explanation of the drawing]

Fig. 1 is a schematic explanatory diagram of a manual defective solder removal device showing one embodiment of the present invention, Fig. 2 is an explanatory diagram showing a cutter mechanism for a suction wire, and Fig. 3 (a) Φ) (C) is Each is an enlarged sectional view of a printed circuit board showing the process of removing defective solder in a manual defective solder removal device, FIG. 4 is a plan view of an automatic defective solder removal device showing another embodiment of the present invention, and FIG. 5 is an automatic defective solder removal device. A side view of the solder removal device, FIG. 6 is a schematic explanatory diagram showing the blotting wire supply device, and FIGS. 7(a), (b), and (C) are respectively the removal of defective solder and soldering in the automatic defective solder removal device. 1 is an enlarged cross-sectional view of a printed circuit board showing a process. 1- Manual defective solder removal device 2- Soldering iron main body 3.23- Blotting wire 4- Blotting wire supply unit 9- Thread solder 17- Printed circuit board 19- Pin 20-・ Bad solder 21-- Automatic defective solder removal Device 22 - Robot arm head 24 - Set finger unit 25 - Soldering iron unit Fig. 1 Fig. 6

Claims (5)

[Claims] (1) A blotting wire is pressed against the defective solder on the printed circuit board, and while applying a small amount of molten solder to the blotting wire, the defective solder is heated and melted, and the molten defective solder is removed by capillary action due to the blotting wire. A method for removing defective solder, characterized in that the defective solder is removed by blotting. (2) A device for removing defective solder, characterized in that a soldering iron body having a soldering iron tip at its tip is integrally provided with a blotting wire supply unit that can freely supply a blotting wire to the tip of the soldering iron tip. (3) a suction wire supply unit that can freely supply a suction wire to a soldering iron body having a soldering iron tip at the tip, and a thread solder supply unit that can freely supply thread solder to the tip of the soldering iron tip; A defective solder removal device characterized by being integrally provided with. (4) A blotting wire supply unit that is provided with a blotting wire cutter mechanism that can freely supply blotting wire toward the tip of the soldering iron tip and cut the supplied blotting wire to the soldering iron body that has a soldering iron tip at the tip, and the soldering iron tip. A device for removing defective solder, characterized in that it is integrally provided with a thread solder supply unit that can freely supply thread solder to the tip of the thread solder. (5) A set finger unit that grips the suction wire and presses it against the defective solder on the printed circuit board, and a soldering iron unit that applies heat treatment to the defective solder on the head of the robot arm that can move to any position and freely rotate. A device for removing defective solder, characterized in that it is assembled with.