JPH08162754A - Automatic correction system for defective soldering - Google Patents

Abstract

PURPOSE: To remove solder from a defective soldering part by shifting a soldering iron, provided with a recess in the soldering face thereof, up and down with respect to a printed wiring board. CONSTITUTION: An X-Y stage 2 is shifted such that the preheated part at a solder removing part 3 is located on the lower surface of a selected soldering iron 6. When the soldering iron 6 is lowered to touch a copper wick, a solder collected in a recess is absorbed by the copper wick and the soldering face is wetted with the solder. The soldering iron 6 is then elevated and the soldering point to be corrected by the X-Y stage 2 is shifted directly under a needle-like pipe at a flux supply section 8. The needle-like pipe is elevated after applying a flux and the X-Y stage 2 is shifted such that the soldering correction point is located directly under the soldering iron 6. Finally, the soldering iron 6 is lowered and the soldering correction point is heated to fuse the solder applied thereto thus removing the solder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention automatically corrects defective soldering in a chip component or an integrated circuit which is soldered to a printed wiring board, that is, insufficient solder, excessive solder or bridge. The present invention relates to a solder defect automatic correction device.

[0002]

2. Description of the Related Art Conventionally, it is common to manually correct defective soldering points on a printed wiring board that has already been mounted. However, there is a problem that it takes a considerable amount of skill to look for a defective portion with human eyes, and the manual correction is troublesome.

Therefore, a device has been developed which automatically corrects a soldering defect without manual labor. For example, the soldered part of the printed wiring board is photographed with a video camera, the image is captured as an image, and this image is compared with the image of a normal soldered part. After melting, the solder is sucked to remove the solder, and then the automatic soldering device again applies solder to the defective soldering portion.

[0004]

By the way, in the above-mentioned conventional automatic soldering defect correcting device, the removal of the solder at the defective soldering portion and the automatic soldering device are separate entities. However, it takes time to correct the solder, and it is impossible to confirm whether or not the solder has been removed correctly even when removing the solder. Therefore, there is a problem in reliability as an automatic correction device.

The present invention is intended to solve the above-mentioned problems, and an object of the present invention is to move a soldering iron having a recessed portion on a soldering surface with respect to a printed wiring board up and down, thereby soldering. The solder at the defective part can be removed, and after the solder is supplied to the recess before the solder removal,
Another object of the present invention is to provide an automatic solder defect correcting device which can keep the soldering surface clean because the solder is removed, and which can ensure the stability of the correction work.

Further, since the printed wiring board is moved only by the vertical movement of the soldering iron, the work time for correction can be shortened, and the tip of the soldering iron has a prismatic shape, so that the shape and arrangement direction of the parts can be improved. It is possible to continuously correct defective solder points without changing or rotating the soldering iron according to
It is another object of the present invention to provide an automatic solder defect correction device capable of melting a solder in a short time by supplying flux to a solder correction point before solder correction.

Further, in the case where there is insufficient solder at the solder correction point, a necessary amount of solder is automatically supplied to the concave portion which is the soldering surface, so that reliable solder defect correction can be performed and the tip of the soldering iron It is an object of the present invention to provide an automatic solder defect correction device that can keep the iron tip clean because it removes the carbide of the flux attached to the part.

[0008]

SUMMARY OF THE INVENTION The automatic solder defect correcting apparatus of the present invention is intended to achieve the above-mentioned object, and means for moving a printed wiring board having a defective soldering portion in the XY directions. An XY stage, a soldering iron that is vertically movable with respect to the XY stage, and has a concave portion formed on a soldering surface, and the soldering iron mounted on the XY stage. A solder supply unit that supplies solder to the recess, a solder removal unit that removes the solder in the recess of the soldering iron, the defective soldering point and the defective state data are stored in memory, and the X data is stored based on the memory data. -Y
A control means for controlling the stage and controlling the upper and lower parts of the soldering iron and the solder supply part is provided.

Further, the control means moves the XY stage at a defective solder portion on the printed wiring board to a position right below the soldering iron in the operation of correcting the defective soldering portion,
Next, the soldering surface of the soldering iron is lowered so as to come into contact with the defective soldering portion, and then the soldering iron is raised while moving the XY stage in the extension line direction of the soldering portion of the electronic component. To control it.

Further, it is desirable that the tip of the soldering iron is formed in a prismatic shape, and the concave portion is formed over substantially the entire soldering surface which is the lower surface of the ironing tip. A flux applicator may be provided to apply the flux before the correction with the soldering iron.

Furthermore, on the XY stage,
It is desirable to provide a flux removing section for removing carbide of the flux adhering to the tip portion of the soldering iron after the solder automatic correction work is performed.

[0012]

In the automatic solder defect correcting device of the present invention configured as described above, a concave portion is formed on the soldering surface of the soldering iron, and the solder is supplied from the solder supply portion to the concave portion to collect the solder.
When there is no need to supply solder to the solder correction point as in the case of excess solder, the XY stage moves so that the solder remover is located directly below the soldering iron to remove the solder accumulated in the recess. The solder is wet and after that,
The solder correction point of the printed wiring board is moved right below the soldering iron by the XY stage.

Then, the soldering iron descends to the solder correction point to supply solder or melt the solder, and
In this state, the XY stage moves the printed wiring board so that the soldering surface of the soldering iron moves toward the tip of the lead and raises the soldering iron to correct the solder.

Further, since the flux is automatically applied to the solder correction points at the time of the solder correction, the solder paste becomes good in the correction work, and the correction work can be performed accurately.
Further, the flux attached to the tip of the soldering iron is moved every predetermined number of times so that the XY stage is moved so that the flux removing portion moves to the lower surface of the soldering iron, and then the soldering iron is lowered to be attached to the ironing tip. The flux is removed by the flux removing section to keep the iron tip clean.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an automatic solder defect correcting apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 and FIG. 2 are a plan view and a side view showing a schematic diagram of the whole, and a transport table fixed to the X stage 21, the Y stage 22 and the Y stage 22 on the upper surface of the base 1 and holding a printed wiring board. An XY stage 2 such as 23 is attached. Then, the solder removing section 3 shown in FIG. 3 and the flux removing section 4 shown in FIG. 4 are attached to the XY stage 2.

Further, a gate pillar type support base 5 is attached to the base 1, and two large and small soldering irons 6 shown in FIG. 4 are attached to the supporting base 5 in a hanging state, and further, each soldering iron 6
For supplying solder to the pair of solder supply parts 7 shown in FIG.
Are mounted so as to be movable in parallel, and further, a flux supply section 8 shown in FIG.

Next, the details of each of the above-mentioned components will be described. The solder removing portion 3 is attached to an end portion of the transport table 23 of the XY stage 2, and as shown in FIG. 3, a copper wick 31 in which a thin copper wire is woven into a strip shape, and the copper wick 3
1. A bobbin 32 around which 1 is wound, a feeding portion 33 formed of a pair of gears that pulls out from the bobbin 32 and sandwiches the copper wick 31, and a copper wick 3 to which solder is attached.
A cutting part 34 such as an air nipper for cutting 1 into desired lengths
And a storage box 36 for storing a preheating portion 35 for heating the copper wick 31 pulled out from the bobbin 32 by the feeding portion 33 and a cut piece of the copper wick 31 cut by the cutting portion 34. .

The flux removing portion 4 is attached to a portion of the XY stage 2 adjacent to the solder removing portion 3 and, as shown in FIG. 4, is housed in a metal box 41 of stainless steel or the like, and the metal box 41. The removing material 42 is made of heat-resistant sponge-like cellulose and has a groove 42a formed on the surface into which the tip of the soldering iron 6 is inserted.

The soldering iron 6 is vertically movably attached to the top plate of the support base 5, and as shown in FIG. 5, a soldering iron tip 61 is formed in a quadrangular shape, and the soldering iron 62 is recessed over substantially the entire surface of the soldering surface 62. 62a is formed. The recess 62a serves to absorb the melted solder by a capillary phenomenon. The soldering iron 6 according to the present embodiment is prepared in two sizes, that is, a soldering iron 6 having a large size and a soldering surface having a different size.

The solder supply section 7 is attached to the side surface of the top plate of the support base 5, and as shown in FIG. 6, the thread solder 71, the bobbin 72 around which the thread solder is wound, and the thread solder 71. By a feed unit 73 composed of a pair of gears that is pulled out from the bobbin 72 and sandwiched and fed, and a moving device (not shown) in the left and right direction with the tip end of the thread solder 71 inserted,
The soldering iron 6 includes a guide pipe 74 that reciprocates between the position of the soldering surface 62a and the retracted position.

Like the soldering iron 6, the flux supplying portion 8 is attached to the support base 5 so as to be vertically movable.
As shown in FIG. 4, a flux container 81 for containing a liquid flux in a pressurized state, a valve 82 attached to the outlet of the container 81 and opened / closed at a predetermined time, and a flux from the valve 82 are applied to a vertically movable shaft. It is composed of a supply pipe 84 for supplying to the attached needle pipe 83.

Next, the general operation of the entire system will be described based on the above configuration. First, mount the mounted printed wiring board on X-
When the Y stage 2 is placed on the carrying table 23, a sending unit 73 of the solder supplying unit 7 first operates to send a certain amount of the solder wire 71 into the guide pipe 74 by a command from a control unit (not shown). The guide pipe 74 horizontally moves the wire solder 71 protruding from the tip to the lower surface of the soldering surface 62 of the soldering iron 6.

In the movement of the guide pipe 74, the control means is instructed to the defective portion of solder on the printed wiring board, that is, which part (which pin) of which component and solder content (unsolder, small amount of solder, insufficient wetting). , Excess solder, bridge, etc.) is input from a known solder defect inspection device, and which of the large and small solder trowels 6 should be used is determined, so move to the solder trowel 6 in the commanded direction. To do.

Then, as the guide pipe 74 moves, the thread solder 71 is moved by the soldering iron 6 on the selected side.
Is melted, and the melted solder is applied to the concave portion 6 of the soldering surface 62.
It collects in 2a. Then, the XY stage 2 is moved so that the preheating part 35 in the solder removing part 3 is located on the lower surface of the selected soldering iron 6.

When this movement is completed, the soldering iron 6 descends and the soldering surface 62 comes into contact with the copper wick 31 located on the upper surface of the preheating portion 35. As a result, the solder accumulated in the recess 62a is absorbed by the copper wick 31, and the soldering surface 62 becomes wet with the solder.

Next, the soldering iron 6 rises to its original position,
In this state, the solder point corrected by the XY stage 2 moves so as to be located directly below the needle-shaped pipe 83 in the flux supply section 8. Then, the needle-shaped pipe 83 descends, and a small amount of flux sent by the valve 82 is applied to the correction portion.

Then, when the application of the flux is completed,
The needle pipe 83 rises to its original position, and the XY stage 2 moves again so that the solder correction point is located directly below the soldering iron 6. Then, the soldering iron 6 descends again to heat the solder-corrected portion to which the flux has been applied to melt the applied solder. When there is no solder or a small amount of solder, a required amount of new solder is supplied to the soldering iron concave portion during the flux applying operation, and the soldering iron 6 is lowered.

Next, while the molten solder is held between the repaired portion and the concave portion 62a, the control means is operated as shown in FIGS.
As shown in FIG. 3, the printed wiring board is moved via the XY stage 2 so that the soldering surface of the soldering iron 6 faces the lead tip direction of the electronic component, and the soldering iron 6 is raised.

Next, the operation of correcting the solder by lowering and raising the soldering iron 6 and moving the XY stage 2 will be described with reference to FIGS. In the figure, P
Is a printed wiring board, R is a land pattern, L is a lead in an electronic component such as a flat package, F is a flux, H is a molten solder, and H'is a solder.

FIG. 8 shows a solder correction state for each defect content of the solder with respect to the lead L. (a) shows a state in which the solder has not been soldered and the amount of the solder is small. Solder supply unit 7 is provided in recess 62a.
After supplying the required amount of new solder, the soldering iron 6 is lowered.

In this descending operation, the XY stage 2 is controlled by the control means so that the central portion of the concave portion 62a of the soldering iron 6 descends to the tip portion of the lead L.
Will be moved. Before this descent, the flux application by the flux supply unit 8 is completed.

In this state, when the soldering iron 6 descends and the lead L is heated, the solder H in the recess 62a flows out along the solder supply portion 7 activated by the flux. After the solder H flows out, the XY stage 2 is moved to the side opposite to the arrow. During this time, the soldering surface 62 has the lead L,
Move along the land pattern R.

Then, the soldering iron 6 is gently raised to cause the solder H to lead L as if drawing a parabola.
Is soldered to the round R from the tip of the. In addition, (b) is the case of poor solder wetting, and
(c) shows the case of excessive solder, and (d) shows the case of bridge. In any case, the same operation as described above is performed, but the lower position of the soldering iron 6 and the tip of the soldering iron are used. The amount of the molten solder H in the concave portion 62a is controlled according to the defective state.

FIG. 9 shows a correcting operation of a defective soldering portion due to a difference in shape of electronic parts. (A) shows a movement locus of a soldering iron tip when a soldering part is large like a chip part, and (b) shows
Is the lead of the flat package described above, and the movement path of the iron tip in the case of the bridge state,
(c) shows the movement trajectory of the iron tip in the case of a lead wire.

FIG. 10 shows a correction operation of a defective soldering portion due to a difference in heat capacity between soldered parts of an electronic component. (A) shows a moving locus of the tip when the heat capacity of the lead part is large, and (b) shows The movement locus of the iron tip when the heat capacity is small is shown, the black circle portion shows the initial heating position, and the area between the arrows shows the contact movement range. As can be seen from this figure, when the heat capacity is large, the solder H is melted by using a large soldering iron 6 and controlling the time of initial heating and contact movement.

Thus, when the solder correction work is completed,
The XY stage 2 moves so that the solder removing portion 3 is located directly below the soldering iron 6. On the other hand, the solder supply section 7 supplies the solder into the recess 62a by the above-described operation,
The above operation is repeated.

It should be noted that the number of times 1
At the same time, the XY stage 2 moves so that the soldering iron 6 comes right above the flux removing portion 4. And solder iron 6
The iron tip descends to one end of the groove 42a in the removing material 42. In this state, the XY stage 2 moves and the iron tip of the soldering iron 6 moves along the groove 42a to remove the flux attached to the iron tip.

[0038]

As described above, according to the present invention, a concave portion is formed on the soldering surface of the soldering iron, and a required amount of new solder is formed in the concave portion in accordance with defect information output from a known soldering defect inspection apparatus. Since the solder supply section and the solder removal section are controlled so as to hold the solder trowel, the XY stage is moved thereafter to move the solder correction point directly below the soldering iron, and the soldering iron is lowered. , Solder can be corrected automatically.

In the solder correction operation, after the soldering iron descends to melt the solder, the soldering iron moves the printed wiring board toward the tip of the lead of the electronic component by the XY stage, and the soldering iron further leads. Since it descends along the shape and then rises again, it is possible to deal with various solder defects, and flux is automatically applied to the solder correction points at the time of solder correction. Correct soldering work with good solder paste.

Further, since the flux carbide adhered to the soldering iron tip of the soldering iron is also removed by the flux removing section every predetermined number of times, the ironing tip is always kept clean and the solder paste is good, and the shape of the iron tip is changed. The prismatic shape has effects such as being able to deal with solder defect correction of various electronic components.

[Brief description of drawings]

FIG. 1 is a plan view showing an automatic solder defect correcting apparatus according to the present invention.

FIG. 2 is a front view of the above.

FIG. 3 is a front view showing an outline of a solder removing section.

FIG. 4 is a perspective view showing an outline of a flux removing unit.

FIG. 5 is a perspective view of a tip of a soldering iron.

FIG. 6 is a front view showing an outline of a solder supply section.

FIG. 7 is a front view showing an outline of a flux supply unit.

FIG. 8 is an explanatory diagram showing a correction operation for each content of defective solder.

FIG. 9 is an explanatory diagram showing a correction operation due to a shape difference of a defective solder portion.

FIG. 10 is an explanatory diagram showing a correction operation due to a difference in heat capacity of a defective solder portion.

[Explanation of symbols]

 2 XY stage 3 Solder removal part 4 Flux removal part 6 Soldering iron 62 Soldering surface 62a Recess 7 Solder supply part 8 Flux supply part

Claims (5)

[Claims] 1. A printed wiring board having defective soldering points is X-shaped.
An XY stage that moves in the −Y direction, a soldering iron that can move in the vertical direction with respect to the XY stage, and has a recess formed in the soldering surface, and is mounted on the XY stage. A solder supply section for supplying solder to the recess of the soldering iron, a solder removing section for removing the solder in the recess of the soldering iron, the soldering defective portion and the data of the defective state are stored in the memory, and An automatic solder defect correcting device comprising: a control unit that controls the XY stage based on data, and controls the up and down of the soldering iron and the solder supply unit. 2. The controller controls the XY stage to move a defective solder portion on a printed wiring board to a position directly below the soldering iron in a soldering defective portion correcting operation, and then, a soldering surface of the soldering iron. Is lowered so as to come into contact with the defective solder point, and then the XY stage is moved in the direction of the extension line of the solder point of the electronic component, and the soldering iron is controlled to be raised. Automatic solder defect correction device. 3. The soldering iron tip of the soldering iron is formed in a prismatic shape, and the recess is formed over substantially the entire soldering surface, which is the lower surface of the soldering iron tip.
Solder defect automatic correction device described. 4. The automatic solder defect correcting device according to claim 1, further comprising a flux applying section for applying flux to the defective solder portion before the solder iron is corrected. 5. A flux removing portion is provided on the XY stage, which removes carbides of the flux adhering to the tip portion of the soldering iron after the solder automatic correction work is performed. The automatic solder defect correcting device according to claim 1, which is characterized in that.