JPH0669641A - Solder melter of circuit board surface - Google Patents

Abstract

PURPOSE:To prevent a solder melting hot air from exerting influences on portions excluding an objective one in a solder melter on the circuit board surface. CONSTITUTION:In a solder melter on the circuit board 8 surface in which a hot wind 20 is sprayed to a solder 18 in a soldering part of a circuit part 15 which is mounted to the circuit board 8 surface to melt a solder with the hot air, this embodiment comprises a jet 21 for spraying a hot wind to the solder part 18 to be melted and an inducing frame 30 for enclosing the hot air 20 and inducing and discharging it outside the circuit board so that it may not expand along the circuit board 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solder melting device for a soldering portion of a circuit component mounted on the surface of a circuit board.

In the field of electronic and communication, a circuit pattern is formed on a circuit board such as a ceramic board or a printed board, and circuit components are mounted and soldered on the circuit pattern to form a predetermined circuit function. Due to the recent demand for high-density packaging, surface mounting technology (SMT) has been applied to such circuit components to form circuits on both sides of the circuit board. A surface mount component (SMD) is used as a circuit component applied to this surface mounting technique, but a large number of lead terminals are provided in components such as IC and LSI, and these lead terminals are respectively soldered to the pattern of the circuit board. Connected by.

It may be necessary to remove such circuit components for reasons such as circuit adjustment, testing, and maintenance. In addition, circuit parts must be re-soldered and attached to the removed parts.

In order to remove such circuit components, conventionally, the solder of a lead terminal at each location is heated and melted by a soldering iron, and the molten solder is sucked and removed by a solder suction device to remove the solder of all the lead terminals. The method was that the circuit components could be removed only after they were removed. Instead of such inconvenient means, a method has been applied in which hot air having a temperature not lower than the melting temperature of the solder is blown to the solder portion to melt the solder all at once.

This solder melting apparatus is as shown in the side view of the schematic construction of FIG. 4, and includes a movable base 3 in the X direction which is movable along a guide 2 on the base 1 in the left-right direction on the paper surface. X
An XY moving table 6 that includes a direction moving table 3 and a Y-direction moving table 5 that is movable along a guide 4 orthogonal to the plane of the drawing.
A hot air generating device 9 above the circuit board 8 mounted and fixed on the mounting base 7 above this; a hot air blowing unit 10 extending downward from this device to approach the surface of the circuit board 8; It is composed of a support arm 11 that supports the hot air generator 9 and a control device 12 that controls and operates the whole.

By operating the controller 12, XY
The moving table 6 is moved to position the desired circuit component 15 mounted on the circuit board 8 to be removed directly below the hot air blowing unit 10. Then, the hot air generator 9 is lowered to bring the hot air jet unit 10 close to the circuit component 15,
The hot air generator 9 is operated to generate hot air and the hot air jet unit 1
Since the solder is collectively melted by jetting and spraying from the jet outlet of 0 toward the soldering portion of the circuit component 15, the circuit component 15 can be lifted and removed.

When the circuit component 15 is mounted on the circuit board 8 by soldering, the solder can be melted and collectively soldered by supplying the solder and blowing hot air.
Lead-tin eutectic solder For example, solder having a melting point of 180 ° C. is blown with hot air having a temperature of 250 ° C. for 5 to 10 seconds to be melted. As described above, it is important to blow hot air at a high temperature for a short time to melt the air so that the temperature does not affect the components.

[0008]

2. Description of the Related Art A solder ejecting unit of a conventional solder melting apparatus will be described with reference to a side sectional view of FIG. 5, which shows an LSI soldered to a wiring pattern on a circuit board 8.
Blower tube 1 from the hot air generator 9 toward the soldered portions 18, 18 of the lead terminals 17, 17 of the circuit component 15 such as
The hot air 20 sent by 9 is branched and jetted from the downward jet outlets 21 and 21 of the hot air jet unit 10 as shown by arrows.

When the solder of the soldered portions 18, 18 is melted, the upper surface of the circuit component 15 is suctioned by the vacuum suction device 22, and the circuit component 15 is lifted and removed from the circuit board 8. At the same time, the blowing of the hot air 20 is stopped.

When the circuit component 15 is mounted on the circuit board 8 by soldering, the solder is supplied to position the circuit component 15, and hot air is jetted to melt the solder to stop the supply of the hot air and solidify the solder. The hot air blowing unit 10 is retracted by.

[0011]

According to the above-mentioned conventional solder melting apparatus, the hot air 20 jetted from the jet ports 21 and 21 is used.
Spreads along the upper surface of the circuit board 8 as shown by the arrow,
Other circuit components very close to each other, eg small chip component 2
You will be touching 3, 23, etc. The hot air 20 is supplied and ejected in a large amount, but the temperature is sufficient to melt the solder that is soldering the chip component or the like.

The chip part 23 has a smaller heat capacity including the solder that is soldering the chip part 23 than that of the part that is about to melt the solder. Therefore, the electrodes on both sides of the chip part 23 and the like form a wiring pattern on the circuit board. The soldered portion that has been soldered is melted in a short time, which causes a problem such as displacement of the chip component 23 or the like due to high wind pressure of hot air, or blowout.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solder melting apparatus for a circuit board surface, which solves the above conventional problems and eliminates the influence on other adjacent circuit components. .

[0014]

According to the first aspect of the present invention for solving the above-mentioned problems, according to the first aspect of the invention, hot air is blown to the solder at the soldering portion of the circuit component mounted on the circuit board surface. A solder melting device for the surface of a circuit board that melts solder with the hot air, the jet opening for jetting hot air to the solder portion to be melted, and the hot air jetted from the jet opening spreads along the circuit board. A solder melting device for the surface of a circuit board, which includes a guide frame body that surrounds the circuit board so that it does not exist and guides and discharges it outside the circuit board.

According to a second aspect of the present invention, there is provided a circuit board surface solder melting apparatus for blowing hot air to the solder in a soldering portion of a circuit component mounted on the circuit board surface to melt the solder. A jet port for jetting hot air to the solder portion to be formed, a guide frame body for enclosing the hot air jetted from the jet port so as not to spread along the circuit board and inducing and discharging it outside the circuit board, and the guide frame. A solder melting device for the surface of a circuit board, comprising a retracting means for allowing only the body to be retracted away from the circuit board and confirming the position of the ejection port.

To each of the above inventions, a mode in which an elastic portion is provided on the guide frame body so that the tip of the guide frame body can be brought into close contact with the circuit board surface can be added.

[0017]

According to the above-mentioned gist of the present invention, in the first invention, the hot air blown to the solder portion to be melted is not scattered on the circuit board by the induction frame surrounding it, and the hot air is out of the plane of the circuit board. The neighboring circuit parts are not exposed to hot air because they are induced and discharged.

In the second invention, since only the guide frame is separated from the circuit board and opened, it is possible to easily visually confirm whether or not the position of the hot air outlet corresponds to the soldered portion of the circuit component. Therefore, the guide frame body is placed on the circuit board and brought into contact with it after confirmation, and the solder is melted.

By providing the elastic portion on the guide frame, the end portion can be brought into close contact with the circuit board.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A circuit board surface solder melting apparatus according to the present invention will now be described in detail with reference to the drawings based on an embodiment based on the concept of the above construction. Note that, for ease of understanding, the same parts as those of the related art shown in FIG.

FIG. 1 is a side sectional view of the essential portion of an embodiment of the first invention of the solder melting apparatus of the present invention. In FIG. 1, the hot air blowing unit 10 is directed from the hot air generating device 9 toward the soldered portions 18, 18 of the lead terminals 17, 17 of the circuit component 15 such as LSI soldered to the wiring pattern on the circuit board 8. The hot air 20 sent by the blower pipe 19 is branched, and further downward jet ports 21 and 21 are provided.

In the embodiment of the present invention, the blower pipe 19 has a space so as to surround the ejection ports 21 and 21,
A guide frame body 30 reaching the surface of the circuit board 8 is provided. A large number of holes 31 are formed in the plane portion on the guide frame body 30.

The hot air 20 generated by the hot air generator 9 (shown in FIG. 4) in the upper portion of the above structure is blown into the blower tube 19 and is branched by the hot air blowout unit 10 to be jetted out 2
It is ejected from 1, 21. The hot air is the lead terminals 17, 17
However, the hot air thereafter does not spread along the surface of the circuit board 8 due to the surrounding guide frame body 30 and is directed upward along the inside of the guide frame body 30. It is guided and discharged from the hole 31 on the upper surface to the outside as shown by the arrow.

When the solder is melted, the upper surface of the circuit component 15 is sucked by the vacuum suction device 22 and the circuit component 15 is lifted and removed from the circuit board 8. At the same time, the supply of hot air 20 is stopped.

When the circuit component 15 is mounted on the circuit board 8 by soldering, the solder is supplied to position the circuit component 15, hot air is jetted to melt the solder, and the supply of the hot air is stopped to solidify the solder. The entire hot-air jetting unit 10 is retracted.

By providing the guide frame body 30 for covering the periphery as described above, hot air does not reach other circuit components 23 and the like near the periphery, so that the conventional inconvenience to these circuit components 23 and the like is eliminated. It

In the present invention, in order to confirm visually (indicated by a chain double-dashed line) whether the opening 21 is located at a position corresponding to the soldering portion 18 of the lead terminal 17, it is integrally drawn in the drawing. Can be easily realized by using a transparent and heat-resistant material for the peripheral portion of the guide frame body 30 in the visible range. Examples of such materials include synthetic resins such as silicone resin, heat-resistant glass, and quartz glass.

However, if the position control can be surely performed by incorporating a means such as image recognition, it is not always necessary to make the position transparent, but it can be used in combination.

FIG. 2 shows a sectional side view of the essential parts of an embodiment of the second invention of the solder melting apparatus of the present invention. In FIG. 2, the hot air blowing unit 10 is directed from the hot air generating device 9 toward the soldered portions 18, 18 of the lead terminals 17, 17 of the circuit component 15 such as an LSI soldered to the wiring pattern on the circuit board 8. The hot air 20 sent by the blower pipe 19 is branched, and further downward jet ports 21 and 21 are provided.

In the embodiment of the present invention, the blower pipe 19 has a space so as to surround the ejection ports 21 and 21,
A guide frame body 40 reaching the surface of the circuit board 8 is provided. A large number of holes 41 are formed in the plane portion on the guide frame body 40.

A guide 42 is formed in a portion of the blower pipe 19 where the guide frame 40 is provided. The guide frame 40 is fitted in the guide 42, and the guide frame 40 is vertically moved with respect to the blower pipe 19. It is configured to be movable in any direction. A lever 43 is attached to the guide frame body 40. Incidentally, the fitting portion of the guide 42 and the guide frame body 40 is provided with a means (not shown) for preventing mutual rotation about the axis.

The hot air 20 generated by the hot air generator 9 (shown in FIG. 4) in the upper part of the above structure is sent into the blower pipe 19, and is branched by the hot air blowout unit 10 to be jetted out 2
It is ejected from 1, 21. The hot air is the lead terminals 17, 17
Although the solder of the soldering parts 18, 18 is melted, the hot air thereafter does not spread along the surface of the circuit board 8 by the surrounding guiding frame body 40, but goes upward along the inside of the guiding frame body 40. It is guided and discharged from the hole 41 on the upper surface to the outside as shown by the arrow.

When the solder is melted, the upper surface of the circuit component 15 is sucked by the vacuum suction device 22 and the circuit component 15 is lifted and removed from the circuit board 8. At the same time, the supply of hot air 20 is stopped.

When the circuit component 15 is mounted on the circuit board 8 by soldering, the solder is supplied to position the circuit component 15, and the hot air is jetted to melt the solder to stop the supply of the hot air to stop the solder. The entire hot air blowing unit 10 is retracted by solidification.

By providing the guide frame body 40 for covering the periphery as described above, the hot air does not reach the other circuit components 23 near the periphery, so that the conventional inconvenience to these circuit components 23 is eliminated.

The reason why the guide frame body 40 is vertically movable in the present invention will be described with reference to FIG. First, the XY moving table 6 (shown in FIG. 4) is moved to position the desired circuit component 15 directly below the hot air blowing unit 10. Whether or not this corresponds to an accurate position is determined. Need to visually confirm. Otherwise, it becomes difficult to surely melt the intended solder to be melted.

Then, as shown in FIG. 3, the guide frame 40 is moved upward by holding the lever 43 and stopped by an appropriate fixing means so that the ejection port 21 corresponds to the soldered portion 18 XY. The moving device 6 is finely moved and aligned. This can be easily done by visual confirmation as shown by the chain double-dashed line. Lever 4 when alignment is complete
3, the guide frame body 40 is moved downward to bring the lower end surface into contact with the surface of the circuit board 8.

In this way, the hot air jet 21 and the soldering portion 18 can be reliably aligned by direct visual inspection. The further invention of the present invention resides in that the elastic portion 45 is provided in the middle of the guide frame body 40 shown in FIG. The elastic portion 45 is a diaphragm (bellows) that surrounds the periphery and is elastically movable in the vertical direction. The elastic portion 45 may be made of a thin metal plate for spring, and may be made of heat resistant rubber synthetic resin such as silicone synthetic resin or fluorine synthetic resin. ..

A large number of compression coil springs and compressible leaf springs may be used. In this case, hot air is discharged through the springs, but since it does not affect the surface of the circuit board 8 anymore, there is no problem. That is.

In this embodiment, the elastic portion 45 is provided in the middle of the guide frame body 40. However, the present invention is not limited to this, and in the present invention, the entire guide frame body or the middle portion to the end contacting the circuit board 8 is elastic. Including the part, the effect is the same.

The elastic portion of this embodiment is applicable to the elastic portion of the first invention shown in FIG.
Is included in the invention of. Guide frame 4 of the second invention
Although 0 is movable in the vertical direction and the movement is performed by hand, indirect driving means such as an air cylinder may be applied to this movement, and in case of automation. It is suitable.

As described above, in each of the embodiments, the LSI is used as a circuit component, but the invention can be applied to other surface mount type components such as ICs and chip components. The hot air jetting unit will be detachably replaceable, but it goes without saying that it is included in the scope of the claims of the present invention in any case.

The hot air may be air, but it is convenient to use an inert gas such as nitrogen gas because the molten solder is not oxidized.

[0044]

As described above in detail, according to the solder melting apparatus for a circuit board surface of the present invention, by providing the hot air guide frame surrounding the hot air outlet, the solder is provided around the target circuit component. Since the hot air for melting does not hit, these parts are not affected, and the practical effect that the solder melting work can be performed efficiently is extremely remarkable.

[Brief description of drawings]

FIG. 1 is a side sectional view of an essential part of an embodiment of a first invention of a solder melting apparatus of the present invention.

FIG. 2 is a side sectional view of an essential part of an embodiment of a second invention of the solder melting apparatus of the present invention.

FIG. 3 is an explanatory view showing that an elastic portion is provided on the guide frame body.

FIG. 4 is a schematic side view of a solder melting device.

FIG. 5 is a side sectional view of a main part of a conventional solder melting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base 6 XY movement stand 7 Mounting base 8 Circuit board 9 Hot air generator 10 Hot air blower unit 11 Support arm 12 Control device 15 Circuit parts 17 Lead terminal 18 Soldering part 19 Blower pipe 20 Hot air 21 Jet outlet 22 Vacuum suction Device 23 Chip part 30 Guide frame 31 Hole 40 Guide frame 41 Hole 42 Guide 43 Lever 45 Elastic part

Claims (3)

[Claims] 1. Hot air (20) is applied to the solder (18) in the soldering portion of the circuit component (15) mounted on the surface of the circuit board (8).
A solder melting device for a circuit board surface for blowing hot air to melt solder by means of a jet port (21) for jetting hot air to a solder part (18) to be melted, and hot air jetted from the jet port. And a guide frame body (30) surrounding (20) so as not to spread along the circuit board (8) and guiding and discharging it to the outside of the circuit board. apparatus. 2. Hot air (20) is applied to the solder (18) at the soldering portion of the circuit component (15) mounted on the surface of the circuit board (8).
A solder melting device for a circuit board surface for blowing hot air to melt solder by means of a jet port (21) for jetting hot air to a solder part (18) to be melted, and hot air jetted from the jet port. A guide frame (40) that surrounds the circuit board (8) so as not to spread along the circuit board (8) and guides and discharges it outside the circuit board, and separates only the guide frame body from the circuit board (8). A solder melting apparatus for a circuit board surface, comprising: retracting means (42) (43) for retracting so that the position of the ejection port (21) can be confirmed. 3. The guide frame (30) (40) is provided with an elastic portion (45) so that the tip of the guide frame can be brought into close contact with the surface of the circuit board (8). The circuit board surface solder melting apparatus according to claim 1 or 2.