JPS59110458A - Solder tank - Google Patents

Abstract

PURPOSE:To eliminate imperfect soldering owing to foam, and improves additionally the sticking of solder in secondary soldering by moving many rugged waves formed on the peak surface of the jet waves of the melt ejected in a solder tank in the direction intersecting the traveling direction of a printed circuit board. CONSTITUTION:The melt 5 contained in a solder tank body 4 is pressurized by the rotation of an impeller 8 and is introduced 10 into a jet tank 6, where the melt is run in an arrow A direction through the screw part 12 of a rotating body 11 and is ejected 7. As a result, the projecting parts of the melt 5 are formed in the places of the bodies 11, 14 and the recesses of the melt 5 are formed in the place of projecting parts 13, whereby many rugged waves 5b are formed on the peak surface of the jet wave 5a in the direction intersecting the traveling direction D of a printed circuit board 1. On the other hand, the screw part 12 is moved apparently in an arrow C direction by the rotation of the body 11 in an arrow B direction. Then the side face 13a of the projecting part 13 moves in the arrow C direction in the stage when the melt 5 passes the recessing part 14 in the arrow A direction. The wave 5b at the peak surface of the wave 5a moves in the arrow C direction as well. The melt is thus satisifactorily stuck on the chip parts, etc. mounted densely on the board 1.

Description

DETAILED DESCRIPTION OF THE INVENTION This C-mei is designed to form a large number of uneven waves on the top surface of the jet wave of the solder melt spouted from the jet port provided in the solder elliptical jet tank. This invention relates to a solder mold in which uneven waves are moved in a direction intersecting the running direction of a printed circuit board.

Conventionally, when soldering chip parts such as resistors and capacitors temporarily attached with adhesive, etc., or printed circuit boards with densely packed electronic components using a jet of melted solder, the running direction of the printed circuit board is On the other hand, the parts behind the chip parts and the parts where each chip part is close to each other have a four-part shape, where air and other gases stay and prevent the solder melt from flowing in. In some cases, the adhesive did not adhere, or even if it adhered, a hollow portion was formed and the adhesive did not adhere completely. Furthermore, when bubbles are generated during the soldering process of 11 gJ, there is a drawback that the bubbles cannot be removed even if the solder melt is jetted for a long period of time.

This invention was made to eliminate the above-mentioned drawbacks, and is a solder that eliminates incomplete soldering caused by air bubbles and improves solder adhesion during secondary soldering. This is a very similar offer. The present invention will be explained below based on the drawings.

FIGS. 1(a), (b), and (c) show an embodiment of the present invention; FIG. 1(a) is a partially cutaway front view;
Figure 1(b) is an enlarged side sectional view taken along the line X-X in Figure 1(a), and Figure 1(C) is a partially broken view showing the enlarged part of the manufacturing part in Figure 1(a). It is a front view. In these figures, 1
1 is a printed circuit board with soldering (not shown) attached to the carrier of the device. 2 is a chip component such as a resistor or a capacitor temporarily attached to the printed circuit board 1 with an adhesive or the like, and 3 is a soldering device (not shown) indicating the entire solder bath of the device. 4 is a solder tank main body, 5 is a solder melt, 6 is a jet tank installed in the solder tank main body 4, 7 is a jet port, and 8 is a pressurized solder melt 5 for forced circulation. It is an impeller and is rotated in a fixed direction by a motor 9.

10 is a flow tube, and 11 is a worm-shaped rotating body provided in the jet lower, the narrow part of which is shown in FIG. 1(c).

Reference numeral 12 denotes a threaded portion of the rotating body 11, which serves as a means for generating uneven waves 5b on the top surface of the jet waves 5a of the solder melt 5 flowing from the lower jet flow and for moving the uneven waves 5b in the axial direction. It is formed by a convex portion 13° and a concave portion 14. Reference numeral 15 denotes a rotation shaft of the rotating body 110, which is rotatably supported by the jet tank 6, and can be rotated forward and backward by a motor 16. 1T is a reflux port through which the solder melt 5 flows back. Note that the motors 9 and 16 are provided away from the running direction so as not to interfere with the running of the printed circuit board 10.

Next, the operation will be explained.

The solder melt 5 accommodated in the solder tank body 4 is pressurized by rotation of the impeller 8 driven by the motor 9, and the solder melt 5 is pressurized through the flow tube 1.
0 into the jet tank 6, and the threaded part 12 of the rotating body 11.
It flows in the direction of arrow A in FIGS. 1(b) and 1(c), and is ejected from the jet port T. At the concave portion 14 of the rotating body 11, a large amount of solder melt 5 is spouted, so the height of the solder melt 5 becomes high, and at the convex portion 13, a small amount of solder melt 5 is spouted, so the height of the solder melt 5 is high. The height becomes lower and a large number of uneven waves 5b are formed on the top surface of the jet wave 5a in a direction intersecting with the running direction of the printed circuit board 10 (direction indicated by the arrow in FIG. φ).
is formed.

On the other hand, the motor 16 is also driven at the same time as the motor 9 is driven, and the rotating body 11 is rotated in the direction of the arrow B. Therefore, the threaded portion 12 appears to be in the upward direction of the arrow C (the printed circuit board 1 shown in FIG. 1(b)
0 (direction perpendicular to the direction of the arrow).

Therefore, when the solder melt 5 passes through the concave portion 14 in the direction of the arrow A, the side surface 13a of the convex portion 13 of the solder melt 5 moves in the direction of the arrow C, so that the uneven wave 5 on the top surface of the jet wave 5a
b also moves in the direction of arrow C. Next, when the motor 16 is driven in reverse, the rotating body 11 rotates in the direction opposite to the direction of arrow B, and therefore the uneven wave 5b on the top surface also moves in the direction opposite to the direction of arrow C.

By repeating forward and reverse rotation of the motor 16 in this way,
A large number of uneven waves 5b repeatedly move alternately in the direction of arrow C and in the opposite direction.

Note that the motor 16 does not necessarily need to be rotated in the forward and reverse directions, but may be rotated in the - direction.

Further, the printed circuit board 1 is dried after temporarily attaching the chip components 2 with an adhesive or the like, then subjected to a 7 lux treatment, preheated in a preheating device, and transferred to the solder pot 3. As shown in FIG. 1(b)K, the printed circuit board 1 moves in the direction of the arrow with the solder paste 3 at an upward angle θ with respect to the horizontal line. The chip components 2 are soldered by the jet waves 5a of the solder melt 5, and the chip components 2 are soldered with respect to the running direction of the printed circuit board 10 by a large number of uneven waves 5bK that alternately move across the running direction of the printed circuit board 10. The air bubbles attached to the rear part of the PCB 1 and the concave-shaped areas where each chip component 2 is close to each other are removed. The solder melt 5 adheres well to the surface.

FIGS. 2(a) and 2(b) show another embodiment of the present invention, in which a tubular rotating body with a large number of through holes is provided in the lower jet flow; FIG. 2(a) shows another embodiment of the invention. The partially cutaway front view, FIG. 2(b), is a sectional view taken along YY line in FIG. 2(a).

In these figures, 21 is a tubular rotating body, and 22 is a large number of through holes formed in the rotating body 21 and arranged in a spiral shape. Other Lines The same symbols as in Figure 1 indicate the same parts.

Next, the operations shown in FIGS. 2(a,) and 2(b) will be explained. The pressurized solder melt 5 enters the through hole 22 located below the rotating body 21 from the jet tank 6 as shown by arrow A, passes through the rotating body 21, and rises.

Further, the water is ejected from the through hole 22 located above, and an uneven wave 5c is formed on the top surface of the jet wave 5a.

At the same time, when the rotating body 21 repeats rotation in the direction of arrow B (opposite direction if necessary), the through hole 22 appears to move in the upward arrow C direction and the opposite direction at the top 21a of the rotating body 21. Therefore, the large number of uneven waves 5c also repeatedly move in each direction. In addition, the shape of each uneven wave 5c is shown in Fig. 1 (
The uneven waves 5b generated by the rotating body 11 in e) are more finely disturbed than the uneven waves 5b.

FIGS. 3(a) and 3(b) show still another embodiment of the present invention, FIG. 3(a) is a partially broken pressure surface view of the main part, and FIG. 3(b) is a perspective view of the same. It is. In these figures, 3
1 is a jet tank, 32 is a jet port, 33 is an engagement groove formed in the inner longitudinal direction of the jet port 32, 34 is a rectangular plate movably engaged with the retaining groove 33, 35 Numerous through holes are formed in the plate 34, and 36 is a piston for reciprocating the plate 34 in the direction of the arrow E, which is connected to the plate 34 via the prad 3T.

Next, the operation will be explained. The solder melt 5 is in the jet tank 3
1 to reach the plate 34, and from each through hole 35 arrow A
A large number of uneven waves 5d are formed by ejecting in the direction.

At the same time, due to the reciprocating drive of the piston 36, the plate body 34 is also
Since the reciprocating motion is repeated in the direction, the many uneven waves 5d also repeat the reciprocating motion in the direction of the arrow E.

FIGS. 4(a) and 4(b) are perspective views showing other shapes of the through holes in the plate 34 of FIG. A large number of oval through holes 39 are formed in a diagonal direction (also diagonal to the direction of arrow E in which the printed circuit board 1 travels); 1
This is a large number of oval through holes formed in the same direction (with respect to the direction of the arrow in which it runs).

When the plate body 34 shown in FIGS. 4(a) and 4(b) is used in the jet tank 31 shown in FIG. A large number of uneven waves corresponding to the shape can be obtained.

5(a) and 5(b) show still another embodiment of the present invention, FIG. 5(a') is a partially broken pressure surface view of the main part, and FIG. 5(b) is also a perspective view. It is a diagram. In these figures, 41 is a jet tank, and jet ports 42. Engagement groove 43. An insertion hole 44 is formed. 45 is an endless belt made of heat-resistant rubber, synthetic resin, etc., and has many through holes 46.
is formed. The belt 45 is inserted into the engagement groove 43 with 'Mfl'
l] is inserted into the insertion hole 44, and the drive shaft 41.
It is wound around the driven shaft 48. 49 is the drive shaft 4
This is the motor that drives the T.

Next, the operations shown in FIGS. 5(a) and 5(b) will be explained.

The pressurized solder melt 5 is transferred to the belt 4 as shown by arrow A.
5 enters the through hole 46 below the belt 45, and further ejects from the through hole 46 above the belt 45, forming a large number of uneven waves 5e.

At the same time, when the motor 49 repeats forward and reverse rotation (in the direction of arrow B and the opposite direction), the through hole 46 above the belt 45 moves in the direction of arrow C and the opposite direction, so that a large number of uneven waves 5e are also generated. Repeat the movement in the direction of arrow C and in the opposite direction.

Note that the means for creating the above-mentioned uneven waves is provided on the printed circuit board 1.
The soldering performance can be further improved by providing two stages in the traveling direction of the uneven waves and by reversing the traveling directions of the uneven waves. Furthermore, it goes without saying that the present invention can also be applied to a full-surface flow dip type solder pot.

As explained above, the present invention includes a jet tank which houses the solder melt in the solder tank main body and forcibly circulates the solder melt by pressurizing the solder melt with an impeller, and is provided above the jet tank. In a soldering tank where printed circuit boards on which electronic components are mounted are soldered using jet waves emitted from jet ports, the top surface of the jet waves is made to form a large number of uneven waves in a direction that intersects with the running direction of the printed circuit board. Since a means for moving a large number of uneven white waves in a direction crossing the running direction of the printed circuit board is provided in the jet tank, the uneven waves on the top surface of the jet waves move in a direction crossing the running direction of the printed circuit board. As a result, air bubbles or It has the advantage of eliminating gas stagnation and allowing complete adhesion of the solder melt.

[Brief explanation of the drawing]

FIGS. 1(a), (b), and (c) show an embodiment of the present invention. FIG. 1(a) is a partially cutaway front view, and FIG. 1(b) is a partially cutaway front view. Fig. 1(c) is an enlarged side sectional view taken along line X-Xm of a); Fig. 1(c) is a partial fracture pressure surface view showing an enlarged view of the main part of Fig. 1(a); Fig. 2(a), (b) 2-) shows a partially cutaway front view, FIG. 2(b) is a sectional view taken along the line Y--Y in FIG. (&), <b') show still another embodiment of the present invention, in which Fig. 3(a) is a partially cutaway front view of the main part, Fig. 3(b) is a perspective view, and Fig. 4(b) is a perspective view. Figure (a
) and (b) are perspective views showing other shapes of the through holes in the plate shown in FIG. 3, and FIGS. 5(a) and (b) show still other embodiments of the invention. Figure 5 (&)
5(b) is a partially cutaway front view of the main part, and FIG. 5(b) is a perspective view. In the figure, 1 is a printed circuit board, 2 is a chip component, 3 is a solder bath, 4 is a solder bath body, 5 is a solder melt, 5a is a jet wave, 5b is an uneven wave, 6 is a jet tank, T is a jet port, 8 is a blade group, 9 and 16 are motors, 10 is a flow pipe, 11 is a rotating body, 1
2 is a threaded portion, 13 is a convex portion, 13a is a side surface, 14 is a concave portion,
15 is a rotating shaft, and 17 is a reflux port. Figure 1 (a) (b) Figure 1 (c) a Figure 1 of Figure 2 (a) a Figure 3 (a) (b) Figure 4 (a> 8

Claims (1)

[Claims] A jet tank is provided in which the solder melt is stored in the solder tank body, and the solder melt is pressurized by an impeller and forced to circulate.The jet waves ejected from the jet port provided above the jet tank generate electronic In a soldering ellipse for soldering to a printed circuit board on which components are mounted, a large number of uneven waves are formed on the top surface of the jet wave in a direction intersecting the running direction of the printed circuit board, and the large number of uneven waves are applied to the printed circuit board. A solder bath characterized in that means for moving the substrate in a direction crossing the running direction of the substrate is provided in the jet bath.