JPS6384768A - Optical beam soldering device - Google Patents

Abstract

PURPOSE:To improve a soldering capacity, etc., by forming plural linear spots by providing a mirror system and cylindrical lens and arranging the pusher to press an IC to a board at a solder melting time. CONSTITUTION:The point light source 5 of a heat light source 4 is provided at 1st focus of an ellipsoidal reflection mirror 6 or its vicinity and 1st, 2nd plane reflection mirrors 9, 10 and a douser 14 are respectively arranged in the four right angles direction with the center line of a reflection mirror 6 as well. The air cylinder 22 for a pusher is arranged at the lower part of the light source lamp 4. The heat light source from the point light source 5 is reflected by the reflection mirror 6, made incident on a cylindrical lens 12 by being reflected in four directions via the mirrors 9, 10, and projected linearly on the lead wire of an electronic component 18. A plunger 24 performs the position correction. With this method, a soldering capacity and joining quality are improved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention irradiates a light beam from an arc thermal light source or the like onto the legs of a chip-type IC mounted on a substrate via cream solder. , the solder is melted by the heat and the above I
This invention relates to an improvement of a light beam soldering device for soldering C legs to a board.

[Conventional technology]

An example of a conventional soldering device using a light beam of this type is shown in FIG. 5, and will be described below.

1 is an ellipsoidal reflecting mirror; 2 is an arc thermal light source that is a point light source placed near its first focus F or first focus F+;
Reference numeral 3 denotes a heated workpiece such as a soldering part placed at the second focal point F2 of the ellipsoidal reflecting mirror 1.

Thermal light source radially generated from the arc thermal light source 2 installed at the first focus F2 of the ellipsoidal reflector 1 is reflected by the ellipsoidal reflector 1 and reaches the second focus F! This second focus F
The heated part such as the soldering part of the heated workpiece 3 placed at 2 is heated in a dot shape according to the optical performance of the arc heat light source 2 and the ellipsoidal reflector 1, and is heated for soldering etc. Processing is performed.

[Problem that the invention seeks to solve]

In the conventional light beam soldering device, the heating processing device using the conventional light beam described above has a focal point of the light beam as a single circular heating spot, so there are several parts to be heated. When the heating spot is located in a spot or in a line, the position of the heating spot must be moved intermittently or continuously scanned in a line.

As a result, work time becomes longer and work efficiency is lowered, and the heated part is melted and solidified at different locations, which causes distortion in the parts one after another, resulting in large stress and strain, which can cause misalignment of parts. There were drawbacks such as frequent occurrence of defects such as defects, and deterioration of reliability.

There is also the problem that if some of the legs of the IC are bent and are floating off the board, soldering to these legs cannot be performed.

[Purpose of the invention]

The present invention is intended to eliminate the above-mentioned drawbacks of the conventional light beam soldering device, and aims to simultaneously irradiate the legs protruding from two or four sides of a chip-type IC with a light beam to
Melt the cream solder on the soldering part of C at once,
Even if the soldering position between the IC leg and the board is slightly misaligned,
To generate an alacment effect to match these and to perform soldering efficiently.

Then, when the cream solder is melted, by pressing the IC from above toward the board, even if any of the legs of the IC are bent and some of the legs are floating off the board, all legs can be removed. The purpose is to perform soldering in close contact with the board to prevent poor soldering due to floating feet, poor soldering due to flux entering between the feet and the board, etc.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention uses a cylindrical lens to irradiate a light beam in the form of a plurality of linear spots onto the foot metal body of a chip-type IC, and also to remove the IC from above the IC when the solder is melted. The gist is that a pusher is provided to press against the board.

[Embodiments of the invention]

Next, an embodiment of the present invention will be explained with reference to FIGS. 1 to 4.
This will be explained below.

In FIG. 1, 4 is an arc thermal light source lamp, 5 is its point light source, 7 is its anode, and 8 is its cathode, with an anode 7 and a cathode 8.
is connected to a lamp power supply (not shown), and the point light source 5 is turned on.

Reference numeral 6 denotes an ellipsoidal reflecting mirror, on which an arc thermal light source lamp 4 is installed so that a point light source 5 is located at or near its first focus, and emits a thermal ray from the point light source 5.

9 is a first plane mirror that reflects the reflected light from the ellipsoidal reflecting mirror 6; 10 is a second plane mirror that reflects the reflected light from the first plane mirror 9; the angle and position of each can be finely adjusted. A mechanism is attached, and the second plane mirror 10 can be moved slightly in the horizontal direction in the drawing by the movement mechanism 11.

Reference numeral 12 denotes a cylindrical lens installed in the reflected light path of the second plane mirror 0. The cylindrical lens 12 is held at a constant angle and can be moved slightly in the horizontal direction in the drawing by a moving mechanism 13.

14 is installed in the reflected light path of the second plane mirror IO,
As shown in Figure 4, there are two light shielding plates in a set.
By changing the interval, the width of the reflected light reaching the cylindrical lens 12 is set.

The light shielding plate 14 can be opened and closed by the opening/closing mechanism 15 that adjusts the width.
In addition to the above-mentioned width adjustment of reflected light and total light shielding, the moving mechanism 1
3, the light shielding plate 14 and the cylindrical lens 12 are always kept at a constant distance.

The above first plane mirror 9, second plane mirror 10, moving mechanism 11.13, cylindrical lens 12, light shielding plate 14
The optical system is arranged in four directions perpendicular to the center line of the ellipsoidal reflecting mirror 6.

16 is a heat-resistant shield glass for protecting the internal optical system of the device from gas or dust generated during processing;
Reference numeral 21 denotes an inlet for cooling fluid sent into the device from a cooling fluid generator (not shown).

A pusher air cylinder 22 is attached below the arc light source lamp 4.

A plunger 24 that is pushed upward by a spring 23 is accommodated in the air cylinder 22.
When compressed air is introduced into 2, the pressure causes the plunger 24 to be pressed down against the spring 23.

A small piston 26 that is pushed downward by a spring 25 is housed in the plunger 24, and when the small piston 26 hits an object when the plunger 24 descends as described above, the small piston 26 is pushed downward by the spring 25. 25, and the object that it hits is pressed down by the pressing force of the spring 25.

Next, the operation of this device will be explained.

Heat rays generated radially from a point light source 5 are reflected by an ellipsoidal reflecting mirror 6 to form an optical path a, and are reflected in four directions by four first plane mirrors 9 to form an optical path.

The light beam on the optical path S is further reflected by the second plane mirror 10 to form an optical path C and enters the cylindrical lens 12.

The cylindrical lens 12 is set at an angle perpendicular to the optical path C and at a position where a sufficient amount of light can enter, and the heat rays condensed in one direction by the cylindrical lens 12 are , a linear spot 17 is irradiated near the lead wire of an electronic component 18 that is a workpiece.

FIG. 2 shows the irradiation situation of this linear spot 17 near the lead wire of the electronic component 18. In the entire process, paste-like solder is applied to this part on the circuit board 19, so this irradiation The solder is melted and soldering is performed.

Therefore, the only thermal influence on the electronic component 18 is heat conduction through the lead wires.

In this way, since all the lead wires of the electronic component 18 are irradiated with the heat light source at the same time, the solder used to solder all the lead wires is melted at the same time.

Therefore, even if the positions of the lead wires of the electronic component 18 and the pattern of the circuit board 19 are slightly misaligned, the surface tension of the molten solder causes the electronic component 18 to move automatically so that the positions of the lead wires and the pattern match. Produces an alignment effect.

In this manner, when the solder melts and the self-alignment effect occurs, compressed air is introduced into the air cylinder 22 and the plunger 24 is lowered.

At this time, when the plunger 24 finishes descending, the small piston 26 hits the top surface of the electronic component 18, and the small piston 26
The height of the circuit board 19 is set so that it is slightly pushed into the plunger 24.

Therefore, the electronic component 18 is pressed against the circuit board 19 by the pressure of the spring 25.

Therefore, even if there is an error or deviation in the bending angle of some of the lead wires of the electronic component 18, these can be corrected.
The pressing force of the spring 25 acts so that all the lead wires come into contact with the circuit board 19.

When the small piston 26 starts pressing the electronic component 18, the irradiation of the heat beam is stopped, and cooling of the solder is started by blowing air, etc., and after the solder hardens,
The compressed air in the air cylinder 22 is removed, the plunger 24 is raised by the force of the spring 23, and the pressure on the electronic component 18 is released.

Next, a case where the size of the electronic component 18 or the shape of the soldering location changes will be described.

First, in order to change the position of the linear spot 17, the moving mechanism 11.13 moves the second plane mirror 10 of the optical system facing
A set of cylindrical lenses and 12 cylindrical lenses are moved in conjunction with each other in opposite directions.

Therefore, the linear spots 17, the opposing linear spots 17a and 17a, and 17b and 17b move in opposite directions to increase or decrease the distance between them to correspond to changes in the soldering position.

In order to change the length of the cotton-like spot 17, the two light-shielding plates 14 are moved in the directions of the arrows in FIG. 4 to increase or decrease the distance therebetween, thereby appropriately shielding the optical path C entering the cylindrical lens 12.

As a result, the length of the emitted light beam that is not focused by the cylindrical lens 12 is adjusted, and the linear spot 17 is
Adjust the length.

If the soldering position is only on the opposing sides of the electronic component 18, one of the opposing linear spots 17a and 17b is completely blocked by the light shielding plate 14, and the unblocked linear spot 17a or 17b is completely blocked. Heat processing is performed using a chisel to prevent unnecessary heating of parts.

In the above embodiment, the moving mechanism 11, 13 and the opening/closing mechanism 15 are each provided with an independent drive source and are operated by this, but one drive source is configured with a constant operating ratio by a speed reduction mechanism, and they are synchronously linked. Also good.

Further, although the ellipsoidal reflecting mirror 6 is used, a parabolic reflecting mirror may also be used. In this case, the reflected light rays will be close to parallel rays, so the first plane mirror 9, the second plane mirror 10
The installation situation of the cylindrical lens 12 also needs to be changed accordingly.

Furthermore, in the above embodiment, four linear spots 17 are formed by four optical systems, but depending on the number of parts to be heated, the number of optical systems may be increased or decreased to adapt to the work. can.

〔Effect of the invention〕

The present invention simultaneously irradiates all the legs of a chip-type electronic component with a plurality of linear spots of light beams like a ridge,
All cream solder can be melted at once and soldering can be done at once.

Then, the surface tension generated when the solder is simultaneously melted allows accurate soldering due to the self-alignment effect that corrects the misalignment of the feet and the board, and the soldering ability can be significantly improved.

Moreover, after this self-alignment effect occurs, the pusher presses the electronic components from above, so even if one of the legs is bent or misaligned and the whole leg cannot come into contact with the board, it can be brought into close contact with the board. It is something that can be done.

Therefore, soldering defects such as poor soldering due to floating legs and poor soldering due to fluff getting between the legs and the pattern on the board are prevented, and perfect soldering can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an embodiment of the present invention, Fig. 2 is a plan view showing the state of a linear spot, Fig. 3 is a sectional view of the pusher part, Fig. 4 is a front view of the light shielding plate part, and Fig. FIG. 5 is a principle diagram of a conventional optical beam soldering device. 4... Arc light source lamp, 6... Ellipsoidal reflector, 9
...First plane mirror, 10...Second plane mirror, 1
2... Cylindrical lens, 14... Light shielding plate, 1
7... Linear spot, 18... Electronic component, 22...
・Air cylinder, 24...Plunger, 26...Small cylinder. Patent applicant: Pioneer Corporation Figure 1 Figure 4 Figure 5

Claims (1)

[Claims] a thermal light source lamp; a mirror system that reflects a light beam from the thermal light source lamp toward a plurality of cylindrical lenses; and a plurality of cylindrical lenses that converge the light beam reflected by the mirror system into a linear shape. The present invention is characterized by comprising a pusher that presses a chip-type IC mounted on a substrate via cream solder from above toward the substrate when the cream solder is melted by irradiation with the light beam. A light beam soldering device.