JPS6397360A - Soldering method - Google Patents

Abstract

PURPOSE:To perform soldering with constant filling amount each time by adjusting so that the solder tip of a string solder feeding device is attained to constant position on each completion of one soldering work. CONSTITUTION:On completion of soldering the rod 10a of a cylinder 10 is contracted and the tip of a string solder 3 is separated from a lead wire 2 and from a base plate 1. A string solder feeding device 5 is then transferred to the tip cutting position of the string solder 3 by moving a supporting block 7 by a motor 6. When the rod 10a of the cylinder 10 is extended thereafter, the string solder feeding device 5 advances, the tip of the string solder 3 is faced to a cutter 9, abutting a correcting wall part 24a with a pipe 18 being rotated further. Now, when the rod 15a of a cylinder 15 is extended, the tip of the string solder 3 is projected from the correcting wall part 24a. A mobile blade 25 is actuated in this state to cut the tip of the strong solder 3. The inconvenience due to under filling or overfilling is surely prevented and the soldering quality can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application 5'F] The present invention relates to a method for soldering wiring etc. to an electric circuit board.

[Conventional technology 1] For example, when soldering to connect wiring to an electric circuit board, in order to automate the soldering work, the solder heating method is to heat the solder from a position distant from the soldering point. A laser beam irradiation method that can be used is preferably used. In this soldering method using a laser beam, in order to control the amount of solder applied, cream solder, which is usually made by dispersing solder in the form of fruit particles in a paste, is driven into a predetermined location by a dispenser, and then this solder is It is common to use a material that is heated and melted by irradiation with a laser beam.

By the way, when cream solder is used, there is a risk that flux may flow into the board during soldering work, and if this flux adheres to the board, the electrical characteristics of the circuit will change. Therefore, after soldering, it is necessary to clean the board and remove the flux, which not only increases the number of steps, but also requires products that cannot be cleaned after soldering. This means that the soldering method using cream solder cannot be used.

[Problems to be Solved by the Invention] In addition to the above-mentioned cream solder, there is thread solder as a solder material, and it is also conceivable to perform soldering using this thread solder. When soldering with thread solder, it is necessary to control the amount of solder solder, but in an automatic machine, this management of the amount of solder is done by controlling the feed amount of chain solder. You will be killed. However, there is a slight variation in the amount of melted solder during each soldering operation.
Although this variation is not a particular problem during a single soldering operation, if the solder is fed at a predetermined pitch, the variation in the amount of melted solder will accumulate during repeated operations, and There is a disadvantage that the amount of solder changes significantly, resulting in excess or deficiency in the amount of solder.

The present invention has been made in view of the above two points, and an object of the present invention is to provide a soldering method that allows the soldering amount to be approximately constant when soldering using thread solder. It is something to do.

[Means for Solving the Problems 1] In order to achieve the above-mentioned object, the present invention provides a method for supplying thread solder to a predetermined location of a workpiece from a thread solder feeding device and performing soldering using a solder heating device. The present invention is characterized in that the tip of the solder in the thread solder feeding device is adjusted to a constant position each time one soldering operation is completed.

[Effect 1] As mentioned above, by soldering with thread solder, the inconvenience of flux flowing out from the soldering position as with cream solder is reliably prevented, and it is necessary to clean it after soldering. Even if these steps are not performed, there is no risk of changes in the characteristics of the electric circuit.

On the other hand, when a solder string is heated with a laser beam or the like, even if the irradiation time of the laser beam is strictly controlled, the amount of solder chain solder that melts is not necessarily constant. However, since the tip of the solder wire is adjusted to be in a constant position after each soldering operation, it is possible to prevent the above-mentioned variation in the amount of melted solder from accumulating. Even if you repeat soldering work, the amount of solder will always remain almost constant.
There will be no excess or deficiency.

If the position of the solder tip is adjusted by cutting the tip after each soldering operation, not only will the mechanism for making this adjustment be simplified, but
Since the tip always has a constant shape, the amount of solder can be controlled more strictly.

[Embodiment 1] Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

First, FIG. 1 shows an example of an apparatus configuration for carrying out the soldering method according to the present invention, and in the figure, 1
2 indicates an electric circuit board, and as shown in FIG.
In order to fix the lead wire 2 to the circuit board 1 and to electrically connect the lead wire 2 to the circuit formed on the board 1, soldering is performed at the soldering point S where the cyst layer is formed in the figure. It has become. In this embodiment, a structure is shown in which soldering can be performed at two soldering points S at the same time.

Two thread solders 3 are used to solder each soldering point S facing each other, and each thread solder 3 is wound on a reel 4 and transferred to a thread solder feeding device 5.
This allows it to be sent out toward the substrate l. The chain thread solder feeder 5 is mounted on a support block 7 that can be moved horizontally back and forth by a motor 6.
The support block 7 is also equipped with a laser beam irradiation device 8 as a heating device for heating and melting the thread solder 3. The support block 7 moves the solder wire feeding device 5 between a soldering position where the solder wire 3 sent from the device is soldered and a tip cutting position where the tip of the solder wire 3 is cut. It can be moved back and forth, and a cutter 9 is installed at the position where the tip of the solder wire 3 is cut.

The solder wire feeding device 5 is supported by a support block 7 so as to be opposed to the substrate 1 at an angle of 45 degrees, and can be displaced toward and away from the substrate 1 by a cylinder 10. . As shown in FIG.
As shown in FIG. 4, the chuck member 11 that simultaneously chucks the Chuck opening pieces 14 are brought into contact with each other and are urged to be in the chuck position, and are reciprocated by the cylinder 13.
The chuck portions 11a and llb are pushed against the spring 12 by
By separating the two, the chuck can be released.

When the solder wire feed device 5 is in the tip cutting position, the solder wire feed device 5 uses a two-step stroke to feed the solder wire 3 by using the chuck member 11 to cut it, and to feed a predetermined amount of solder during soldering work. The solder 3 can be fed, and for this purpose the chuck member 1
1 has two cylinders 15 and 16 in action. Among the cylinders 15 and 18, cylinder 15 is for the first stage stroke, cylinder 16 is for the second stage stroke,
These first stage and second stage stroke cylinders t5.
The rods 15a and lea at te can come into contact with and separate from the wall surface of the chuck member 1, and normally they are in the retracted position in contact with the rod 15a of the first stroke cylinder I5 due to the action of the chuck member 11 spring 17. When the first stroke cylinder 15 is operated, the solder wire 3 is fed by the amount required for cutting, and the rod 15a of the first stroke cylinder 15 is extended. In this state, when the second stage stroke cylinder 16 is operated, the thread solder 3 is fed in an amount necessary to perform soldering in a predetermined amount.

On the other hand, a pair of pipes 18 through which two pieces of thread solder 3 are inserted are installed on the front side of the placement position of the chuck member 11 in the thread solder feeding device 5, and the base ends of the pipes 18 are rotatable. It is supported by a shaft 19 so as to be rotatable in the direction indicated by the arrow in FIG. Further, gears 20, 20 that mesh with each other are connected to each rotating shaft 18. Further, a lever 21 for rotation is connected to one of the rotation shafts, and the lever 21 is always operated by a spring 22 so that the pipe ie
, are held in a state in which they are parallel to each other as shown in FIG. It is configured such that when the rod 10a is extended, the pipes 18, 18 can be displaced towards each other.

Furthermore, the cutter 3 has a fixed blade 2 as shown in FIG.
4, and a pair of movable blades 25 provided on both sides of the fixed blade 24.
．． 25, each movable blade 25 is formed with a groove 25a for positioning the solder wire 3, and the fixed blade 24 has a straightening wall portion for centering the solder wire 3 when cutting it. 24a, 24a.

In addition, 26 in FIG. 3 indicates an unwinding prevention lever to prevent the thread solder 3 from being rewound to the 1)-ru 4 side when the chuck member 1 is returned, and the chain unwinding prevention lever 26 is As shown in FIG. 6, it is constructed by urging a lever 28 swingably attached to a support column 27 in the direction of unwinding the solder wire 3 by a spring 29.

The apparatus for performing soldering has the configuration described above, and a method for performing soldering using this apparatus will now be described.

First, when the support block 7 is at the predetermined origin position,
Two solder wires 3 are introduced into the solder wire feeding device 5 attached to the support block 7, and a predetermined amount of each of these solder wires 3 protrudes from the vibrator 18 via the unwinding prevention lever 26 and the chuck member 11. to hold. At this time, the chuck member 11 is closed, and the cylinders 10 and 15° 16 are held in a contracted state.

Therefore, by operating the motor 6, the support block 7 is first advanced to the tip cutting position, and the rod 1 of the cylinder 10 is
0a is extended and the solder wire feeding device 5 is lowered at an angle of 45°. As a result, the solder wire feeding device 5
The solder thread 3 protruding from the vibrator 18 advances toward the cutter 8, and the tip of the solder chain 3 is positioned below the fixed blade 24 of the cutter 8. When the chain thread solder feeding device 5 comes into contact with the stopper 23, the rod 10a of the cylinder 10 pushes the lever 21 against the spring 22, and as a result, the vibrators 18, 18 are rotated so as to approach each other. , the thread solder 3 is the straightening wall part 2 in the fixed blade 24.
Pushed out by 4a. In this state, when the rod 15a of the first-stage stroke cylinder 15 is extended, the chuck member 11 is further advanced by the rod 15a, and then the movable blade 25 is activated to cut the thread solder 3 and chain it. The tip of the solder wire 3 is in a predetermined position.

By contracting the rod 10a of the cylinder 10 while maintaining the extended state of the rod 15a of the cylinder 15, the tip of the solder wire 3 is pulled up once. Then, the support block 7 is moved by the motor 6 to displace the thread solder feeding device 5 to the soldering position. By lifting the solder wire feeding device 5 once in this way, the tip of the solder wire 3 is prevented from hitting the substrate 1 and being deformed when it advances to the soldering position.

At this soldering position, when the cylinder 1 (1) is extended again, the solder wire feeding device 5 is displaced, and the tip of the solder wire 3 connects the pair of lead wires 2 protruding from the substrate l to a predetermined position. The solder wire feed device 5 moves to a position where it straddles the cylinder with a gap.In this state, the solder wire feeding device 5 comes into contact with the stopper 23 and stops, but the rod 10 of the cylinder 10
a further expands, thereby causing the vibrators 18, 18 to rotate in a direction closer to each other, and as a result, the solder thread 3 is pressed against the lead wire 2, as shown in FIG. becomes.

In this way, with the tip of the solder thread 3 pressed against the lead wire 2, the laser beam irradiation device 8 is activated to irradiate the soldering location S with the laser beam for a short period of time, and the substrate l as the base material is irradiated with the laser beam for a short time. and melt a small amount of solder. Thereafter, the second stage stroke cylinder 16 is operated to advance the chuck member 11 a predetermined distance, and a laser beam is supplied from the laser beam irradiation device 8 to apply solder to a predetermined amount. Therefore, soldering is performed while the wire solder 3 is in contact with the lead wire 2 and the base material is heated, so that the soldering work can be performed extremely smoothly. Become.

When the soldering is completed, the rod 10a of the cylinder 10 is contracted to separate the tip of the solder wire 3 from the lead wire 2 and from the board 1, and the support block 7 is moved by the action of the motor 6. Then, the solder wire feeding device 5 attached to the support block 7 is moved to the position where the tip of the solder wire 3 is cut. At the same time, the cylinder 13 is operated to remove the chuck part 1 of the chuck member 11.
1a is released and the cylinder 15.18 is contracted to return the chuck member 11 to its original position. At this time, the chuck for the solder thread 3 is released, but the action of the rewind lever 28 causes the solder chain thread 3 to be released.
When the chuck member 11, which does not move unnecessarily, returns to its original position, the chuck portion 11a is again displaced to the chuck position.

After the solder wire feeding device 5 is displaced to the tip cutting position, the rod lla of the cylinder 11 is extended.

The chain solder feeder 5 moves forward, and the tip of the solder wire 3 chucked by the chuck member 11 comes to a position facing the straightening wall 24a of the fixed blade 24 in the cutter 8, and as the pipe 18 rotates, the tip of the solder wire 3 is moved forward. It is brought into contact with the correction wall portion 24a. Therefore, when the rod 15a of the first-stage stroke cylinder 15 is extended, the tip of the solder wire 3 protrudes from the correction wall portion 24a of the fixed blade 24. In this state, when the movable blade 25 is operated, the tip of the solder chain string 3 is cut, and at the same time, the solder string 3 is pressed against the straightening wall portion 24a of the fixed blade 24 by the action of the movable blade 25 at the time of cutting. , and its centering is performed.

By cutting the tip of the solder wire 3,
The tip position of the solder chain string 3 can be adjusted to be exactly the same as the tip position at the start of the previous soldering operation.

Therefore, if the stroke of cylinder I5 is set to cut a slightly larger amount than the range of variation in the amount of solder melted each time, even if there is some variation in the amount of melted solder in each time, this Because variations do not accumulate.

Inconveniences such as undersoldering resulting in poor soldering and oversoldering resulting in solder eluting outside the soldering location S are reliably prevented, and the quality of soldered products can be improved.

In the above-mentioned embodiment, the position of the tip of the solder thread was adjusted by cutting the solder chain thread, but a sensor was provided to detect the tip of the solder chain thread, and a single soldering operation was performed. The tip position of the solder thread may be detected at each time. In this case, the tip position of the solder thread is detected using a non-contact sensor, and the solder thread is fed by a positioning device such as a stepping motor. It is necessary to use one with good accuracy. Further, although two soldering points are soldered at the same time, it goes without saying that soldering may be performed at one point or three or more points at one time. Further, although a laser beam is used as a means for heating the solder wire, a soldering iron may be used depending on the location to be soldered.

[Effects of the Invention] As detailed above, in the present invention, the tip position of the solder thread is adjusted to be constant for each soldering operation, so even if soldering is repeated, This eliminates the accumulation of variations in the amount of melted solder, making it possible to perform soldering with a substantially constant amount each time, which is extremely advantageous for automating soldering work using thread solder.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram of an apparatus for carrying out the method of the present invention, Fig. 2 is a plan view of a substrate, Fig. 3 is a plan view of a thread solder feeding device, and Fig. 4 is a partial cross section of a chuck member. Front view,
FIG. 5 is a perspective view of the cutter, FIG. 6 is an explanatory diagram of the structure of the rewind prevention lever, and FIG. 7 is an explanatory diagram of its operation. 1: Electric circuit board, 2: Lead wire, 3: Solder thread, 5:
Thread solder feeding device, JIo, 15.18 Niji cylinder, 7
: Support block, 8: Laser beam irradiation device, 9: Cutter, 11: Chuck member, 18: Pipe, 24: Fixed blade, 25: Movable blade.

Claims (3)

[Claims] (1) When supplying thread solder to a predetermined location on the workpiece from a thread solder feeding device and performing soldering using a solder heating device, the tip of the solder in the thread solder feeding device is applied every time one soldering operation is completed. A soldering method characterized by adjusting the position so that it is at a constant position. (2) The soldering method according to claim (1), characterized in that the position of the tip of the solder wire is adjusted by cutting the tip every time the soldering operation is completed. (3) The soldering method according to claim (1), wherein the solder is heated by irradiating the solder with a laser beam.