JP2001358449A - Jet type soldering device and nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely complete soldering. SOLUTION: This device has a solder storing means, a circuit board carrying means which carries a circuit board, and a jet means which jets molten solder. The jet means has 1st nozzle holes which are formed obliquely at a 1st angle to the horizontal surface and at a 2nd angle to the carrying direction of the circuit board, and 2nd nozzle holes which are formed obliquely at the 1st angle to the horizontal surface and at a 3rd angle different from the 2nd angle to the carrying direction of the circuit board. The molten solder can sufficiently be stuck on a land irrelevantly to the position of the circuit board where an electronic component is mounted, the size of the electronic component, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jet type soldering apparatus and a nozzle.

[0002]

2. Description of the Related Art Conventionally, a circuit board such as a printed board is used in an electronic control device, and various electronic components are mounted on the front and back surfaces of the circuit board. Usually, on the front surface of the circuit board, elements such as ICs, LSIs, and microcomputers having a large number of lead terminals of the electronic components are provided, and on the back surface of the circuit board, many lead terminals of the electronic components are provided. Components such as resistors and capacitors that do not have soldering are soldered. For this purpose, in a first step, solder is attached to a land formed on the surface of the circuit board by pattern printing,
In the step of melting the solder attached to the land, the IC of the electronic component,
An element such as an LSI or a microcomputer is soldered, and in a third step, the resistance of the electronic component,
Temporarily fix parts such as capacitors, and in the fourth step,
The molten solder, that is, the molten solder is sprayed toward the back surface of the circuit board, and the temporarily fixed electronic component is soldered.

[0003] In the fourth step, a jet-type soldering apparatus is used to solder electronic components. The jet soldering apparatus includes a primary nozzle and a secondary nozzle for forming a jet of molten solder. Then, the circuit board on which the electronic components are temporarily fixed is transported on the rail,
Molten solder is sprayed from the primary nozzle toward the back surface of the circuit board and adheres to the lands. Subsequently, molten solder is sprayed from the secondary nozzle, and the molten solder adhered to the lands is evenly distributed. If). In this manner, the terminals of the electronic component and the lands are connected by the solder, and the electronic component can be soldered.

FIG. 2 is a conceptual view of a primary nozzle in a conventional jet-type soldering apparatus, and FIG. 3 is an explanatory diagram of a solder jet in a conventional jet-type soldering apparatus. In FIG. 2, the width direction of the solder bath (not shown) can be represented by the X axis, the transport direction of the circuit board 13 can be represented by the Y axis, and the height direction of the solder bath can be represented by the Z axis.

In FIG. 1, reference numeral 11 denotes a primary nozzle, 12 denotes a plurality of nozzle holes formed in the primary nozzle, and 13 denotes a circuit board such as a printed board. The primary nozzle 11 is disposed in the solder bath so as to protrude from the liquid level of the molten solder. Above the solder bath, a rail (not shown) is provided with a slight inclination in the Y-axis direction, and the circuit board 13 is transported along the rail.

[0006] The nozzle hole 12 has a circular shape,
It is formed side by side in two rows. Each of the nozzle holes 12 belonging to the first row g1 and the second row g2 has X at a predetermined pitch p1.
The nozzle holes 12 formed in the axial direction and belonging to the first row g1 and the nozzle holes 12 belonging to the second row g2 are shifted from each other by half the pitch p1 in the X-axis direction, and
It is formed at a distance w1 in the axial direction.

In addition, the nozzle hole 12 extends in the vertical direction (Z
(In the axial direction) and in a direction substantially perpendicular to the back surface 14 of the circuit board 13, the molten solder injected from the nozzle hole 12 is indicated by an arrow A in FIG. As shown, it hits in a direction substantially perpendicular to the back surface 14.

[0008]

However, in the conventional jet-type soldering apparatus, since the molten solder hits in a direction substantially perpendicular to the back surface 14, the pressure P generated by the molten solder jet is increased. Can not do it. Therefore, depending on the position of the electronic component on the circuit board 13 where the electronic component is mounted, the dimensions of the electronic component, and the like, the molten solder may not adhere to the land and soldering may not be performed.

Therefore, it is conceivable to increase the pressure P. However, if the pressure P is increased, the jet of the molten solder becomes too large, and the molten solder may cover the surface of the circuit board 13. In this case, the solder on the surface is melted, and the electronic component soldered in the second step is displaced or the lead of the electronic component is short-circuited by the solder.

[0010] The present invention solves the problems of the above-mentioned conventional jet-type soldering apparatus, and can surely perform the soldering and does not cover the surface of the circuit board with the molten solder. And a nozzle.

[0011]

In order to achieve the above object, in a jet type soldering apparatus according to the present invention, a circuit board is provided along a solder accommodating means for accommodating molten solder and a transport path formed above the solder accommodating means. And a spraying means for spraying the molten solder contained in the solder containing means.

[0012] The jetting means may include a plurality of first inclines formed to incline at a first angle with respect to a horizontal plane and at a second angle with respect to the transport direction of the circuit board.
A plurality of nozzle holes formed by being inclined at the first angle with respect to the horizontal plane and at a third angle different from the second angle with respect to the transport direction of the circuit board. A second nozzle hole is provided.

In another jet type soldering apparatus according to the present invention, rows are formed by the first and second nozzle holes.

In still another jet-type soldering apparatus according to the present invention, each of the rows is extended in a direction perpendicular to the direction in which the circuit board is transported.

In still another jet-type soldering apparatus according to the present invention, the first angle is set to a front side in a conveying direction of the circuit board.

In still another jet-type soldering apparatus according to the present invention, the second angle is on the left side as viewed from the front in the transport direction of the circuit board, and the third angle is on the circuit board. Is set to the right as viewed from the front in the transport direction.

In the nozzle according to the present invention, a plurality of first nozzles formed to be inclined at a first angle with respect to a horizontal plane and at a second angle with respect to the direction of transport of the circuit board.
The nozzle hole is inclined at the first angle with respect to a horizontal plane, and the second hole is inclined with respect to the transport direction of the circuit board.
And a plurality of second nozzle holes formed to be inclined at a third angle different from the angle of the second nozzle.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 4 is a plan view of the jet-type soldering apparatus according to the embodiment of the present invention, and FIG. 5 is a front view of the jet-type soldering apparatus according to the embodiment of the present invention.

In the drawing, reference numeral 16 denotes a case of a jet-type soldering apparatus, and 17 denotes a pair of rails which extend through the case and carry a circuit board (not shown) such as a printed board. The rails 17 are arranged in parallel with each other and slightly inclined so as to gradually increase from the upstream side to the downstream side in the circuit board conveyance direction. Form. Accordingly, the circuit board is conveyed while being inclined along the rails 17 by driving the circuit board conveying means (not shown) with the upstream end low and the downstream end high.

In the case 16, a heating device 18 such as a far-infrared heater is disposed substantially at the center of the circuit board in the conveying direction. Heat from the back side.

Further, in the case 16, downstream of the heating device 18 in the direction of transport of the circuit board,
A solder tank 20 as solder containing means for containing molten solder is provided, and two nozzles as spraying means for spraying molten solder corresponding to the solder tank 20, in the present embodiment, the primary nozzle 21 And the secondary nozzle 22
Is arranged.

Various electronic components are mounted on the front and back surfaces of the circuit board. Usually, on the front surface of the circuit board, elements such as ICs, LSIs, and microcomputers having a large number of lead terminals of the electronic components are provided, and on the back surface of the circuit board, many lead terminals of the electronic components are provided. Components such as resistors and capacitors that do not have soldering are soldered. Therefore, in soldering each of the electronic components to a circuit board, in a first step, solder is attached to a land formed on the surface of the circuit board by pattern printing, and in a second step, By melting the solder attached to the lands, ICs, LSIs,
A device such as a microcomputer is soldered, and in a third step, components such as a resistor and a capacitor among the electronic components are temporarily fixed to a land formed on the back surface of the circuit board with an adhesive, and a fourth process is performed. In the process, molten solder is sprayed toward the back surface of the circuit board, and the temporarily fixed electronic component is soldered.

Then, in the fourth step, the circuit board on which the electronic components are temporarily fixed is transported on the rail 17,
Molten solder is sprayed from the primary nozzle 21 toward the back surface of the circuit board, adhered to the land,
Molten solder is sprayed from the secondary nozzle 22 to level the molten solder attached to the lands. In this manner, the terminals of the electronic component and the lands are connected by the solder, and the electronic component can be soldered.

In order to inject the molten solder in the primary nozzle 21, a first pump (not shown) as a first pumping means is disposed in the solder bath 20, and the first pump (not shown) is provided by a controller (not shown). The pump is operated. Then, outside the solder bath 20, the first
A motor 23 as a driving means for the motor 2 is provided.
3 and the drive pulley 24 attached to the output shaft
A belt 26 is stretched between a driven pulley 25 and a shaft of the pump. Therefore, the motor 2
By driving the first pump 3, the first pump is operated, and the molten solder in the solder bath 20 can be sent to the primary nozzle 21 to be sprayed.

In order to inject the molten solder in the secondary nozzle 22, a second pump (not shown) as a second pumping means is provided in the solder tank 20, and the second pump is provided by the control device. The pump is operated. A motor 27 as a second driving means is disposed outside the solder bath 20, and a driving pulley 28 attached to an output shaft of the motor 27 and a driven pulley 29 connected to a shaft of the second pump. The belt 31 is stretched between the two. Therefore, the second pump can be operated by driving the motor 27, and the molten solder in the solder bath 20 can be sent to the secondary nozzle 22 and sprayed. In the primary nozzle 21, molten solder is injected from a plurality of nozzle holes to form a plurality of molten solder jets. In the secondary nozzle 22, molten solder is injected from a slit (not shown). The solder is jetted to form a jet having a mountain-like shape, and the molten solder attached to the land is leveled accordingly.

Next, the primary nozzle 21 will be described.

FIG. 1 is a diagram showing a relationship between a jet of molten solder and electronic components according to an embodiment of the present invention, FIG. 6 is a perspective view of a primary nozzle according to the embodiment of the present invention, and FIG. FIG. 8 is a sectional view taken along the line BB of FIG. 7, FIG. 9 is a first view showing a state of transporting a circuit board according to an embodiment of the present invention, and FIG. 10 is an embodiment of the present invention. FIG. 8 is a second diagram showing a state of transport of the circuit board in the embodiment. In FIG. 7, the width direction of the solder bath 20 (FIG. 4) is represented by the X axis, the transport direction of the circuit board 13 (direction of arrow C) is represented by the Y axis, and the height direction of the solder bath 20 is represented by the Z axis. Can be.

In the drawing, reference numeral 21 denotes a primary nozzle which is disposed in the solder bath 20 so as to face the circuit board 13 and protrude from the liquid surface of the molten solder. The primary nozzle 21 has a trapezoidal shape. A nozzle plate 33 facing the circuit board 13 and extending horizontally, and supporting plates 34 and 35 extending obliquely downward from the nozzle plate 33.

Reference numeral 36 denotes a plurality of nozzle holes formed in the primary nozzle 21. The nozzle holes 36 have a circular cross section in a direction perpendicular to the axial direction, and To form a plurality of rows, in this embodiment, two first rows g11 and two second rows g12. Each nozzle hole 36
Are formed in the X-axis direction at a predetermined pitch p2,
The nozzle holes 36 belonging to the first row g11 and the nozzle holes 36 belonging to the second row g12 are formed so as to be shifted from each other by half of the pitch p2 in the X-axis direction and by a distance w2 in the Y-axis direction. . The nozzle holes 36 belonging to the first row g11 form a first nozzle hole, and the nozzle holes 36 belonging to the second row g12 form a second nozzle hole.

As shown in FIG. 8, the nozzle hole 36 has a first angle θ1 (= 1) which is set with respect to a horizontal plane and in front of the circuit board 13 in the transport direction.
30 [°]), the lower end opening 38 and the upper end opening 39 are formed at different positions in the horizontal direction, and each of the openings 38 and 39 has an elliptical shape. Therefore, the molten solder injected from the nozzle hole 36 hits the back surface 14 of the circuit board 13 almost obliquely, so that the molten solder jets without changing the partial pressure in the direction perpendicular to the back surface 14. Pressure can be increased. That is, when the pressure is P2 and the partial pressure is Pa, the partial pressure Pa is Pa = P2 · sin θ1, which is smaller than the pressure P2.

Therefore, by increasing the pressure P2, the molten solder can be adhered to the land 43 regardless of the position on the circuit board 13 where the electronic component 41 is mounted. Can be.

Even if the pressure P2 is increased, the partial pressure Pa can be reduced, so that the jet of the molten solder does not become too large, and the molten solder does not cover the surface 45 of the circuit board 13. There is no.

In the present embodiment, the first angle θ1 is set on the front side in the transport direction of the circuit board 13, but may be set on the rear side in the transport direction of the circuit board 13. Further, in the present embodiment, the first angle θ1 is set to the front side in the transport direction of the circuit board 13 for all the nozzle holes 36, however, the predetermined nozzle holes 36, for example, For the nozzle holes 36 belonging to the first row g11, the first angle θ1 is set to the front side in the transport direction of the circuit board 13, and for the other nozzle holes 36, for example, the nozzle holes 36 belonging to the second row g12, The angle θ1 of 1 may be set on the rear side in the transport direction of the circuit board 13.

By the way, the size of the electronic component 41 is large,
When the molten solder ejected from the nozzle holes 36 is applied to the back surface 14 at a substantially inclined angle when the protrusion protrudes greatly downward from the back surface 14, the vicinity of the downstream side of the electronic component 41 in the transport direction of the circuit board 13 is reduced. In addition, the area AR1 in which the molten solder cannot be directly applied to the back surface 14, the land 43, or the like becomes large. Therefore, in the area AR1, the molten solder cannot be attached to the land 43 with the partial pressure Pa, and soldering cannot be performed.

In order to reduce the size of the area AR1, the nozzle holes 36 are further inclined with respect to the transport direction of the circuit board 13 (Y axis). In this case, the nozzle holes 36 belonging to the first row g11 are
The second angle θ2 (= −20 to −4) with respect to the conveyance direction of No. 3
5 [°]) in the negative direction of the X axis, that is, the circuit board 13.
The opening 39 is inclined leftward toward the front in the transport direction, and the opening 39 is positioned diagonally upper left front of the opening 38. In addition, the nozzle holes 36 belonging to the second row g12 are
3, a third angle θ3 (= + 20 to +45) set differently from the second angle θ2.
[°]), it is inclined rightward toward the forward direction of the X-axis, that is, forward in the transport direction of the circuit board 13, and the opening 3
9 is positioned diagonally upper right front of the opening 38. In addition,
In the present embodiment, the second angle θ2 is set for all the nozzle holes 36 belonging to the first row g11, and the third angle is set for all the nozzle holes 36 belonging to the second row g12.
Is set in the first row g
11 with respect to the predetermined nozzle hole 36 belonging to the second angle θ.
2 and the third angle θ for the remaining nozzle holes 36
3, or the third angle θ3 can be set for the predetermined nozzle holes 36 belonging to the second row g12, and the second angle θ2 can be set for the remaining nozzle holes 36.

Therefore, when the electronic component 41 reaches the primary nozzle 21 as the circuit board 13 is transported,
First, in the vicinity of the downstream side of the electronic component 41, the molten solder sprayed from the nozzle holes 36 belonging to the second row g12 is applied to the land 43 in the direction of arrow F from the lower left rear, and the circuit board 13 is further moved. As it is transported, the molten solder sprayed from the first row g11 belongs to
It is applied to the land 43 in the direction of arrow E from diagonally lower right rear. As described above, the molten solder can be applied to the land 43 from diagonally lower left rear and diagonally lower right rear, so that the area AR1 can be made sufficiently small.

Therefore, regardless of the size of the electronic component 41 on the circuit board 13, the molten solder can be sufficiently adhered to the land 43 with the partial pressure Pa, so that the soldering can be performed reliably.

The nozzle hole 36 belonging to the first row g11 and the second
Since the nozzle holes 36 belonging to the row g12 do not face each other, the injected molten solder does not collide with each other, and the jet pressure P2 is not canceled.

Further, even when the inclination angle of the rail 17 is changed, the first angle θ1 is set in accordance with the inclination angle.
, Soldering can be performed reliably.

The present invention is not limited to the above-described embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0042]

As described above in detail, according to the present invention, in a jet type soldering apparatus, a solder accommodating means for accommodating molten solder and a conveying path formed above the solder accommodating means are provided. A circuit board transporting means for transporting the circuit board along the circuit board; and an ejecting means for ejecting the molten solder accommodated in the solder accommodating means.

The jetting means is provided with a plurality of first inclines formed at a first angle with respect to a horizontal plane and at a second angle with respect to the transport direction of the circuit board.
A plurality of nozzle holes formed by being inclined at the first angle with respect to the horizontal plane and at a third angle different from the second angle with respect to the transport direction of the circuit board. A second nozzle hole is provided.

In this case, the first nozzle hole is formed so as to be inclined at a first angle with respect to a horizontal plane and at a second angle with respect to the transport direction of the circuit board.
The nozzle hole is inclined at the first angle with respect to the horizontal plane, and the second hole is inclined with respect to the transport direction of the circuit board.
And is formed to be inclined at a third angle different from the above angle.

Therefore, when the electronic component reaches the spraying means as the circuit board is transported, first, the molten solder sprayed from the second nozzle hole is applied to the land, and the circuit board is further transported. Accordingly, the molten solder sprayed from the first nozzle hole is applied to the land. As a result, irrespective of the position of the electronic component on the circuit board where the electronic component is mounted, the dimensions of the electronic component, and the like, the molten solder can be sufficiently adhered to the land by the partial pressure, so that the soldering can be reliably performed.

Since the nozzle holes belonging to the first row and the nozzle rows belonging to the second row do not face each other, the injected molten solder does not collide with each other, and the pressure of the jet does not cancel out.

In addition, even if the pressure is increased, the partial pressure can be reduced, so that the jet of the molten solder does not become too large and the surface of the circuit board is not covered with the molten solder.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a relationship between a jet of molten solder and an electronic component according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram of a primary nozzle in a conventional jet type soldering apparatus.

FIG. 3 is an explanatory diagram of a solder jet in a conventional jet-type soldering apparatus.

FIG. 4 is a plan view of the jet type soldering apparatus according to the embodiment of the present invention.

FIG. 5 is a front view of the jet type soldering apparatus according to the embodiment of the present invention.

FIG. 6 is a perspective view of a primary nozzle according to the embodiment of the present invention.

FIG. 7 is a conceptual diagram of a primary nozzle according to the embodiment of the present invention.

FIG. 8 is a sectional view taken along line BB of FIG. 7;

FIG. 9 is a first diagram illustrating a transport state of the circuit board according to the embodiment of the present invention.

FIG. 10 is a second diagram illustrating a state of transporting the circuit board according to the embodiment of the present invention.

[Explanation of symbols]

 13 Circuit Board 17 Rail 20 Solder Bath 21 Primary Nozzle 36 Nozzle Hole g11 First Row g12 Second Row θ1 to θ3 First to Third Angle

Claims (6)

[Claims] 1. A solder accommodating means for accommodating molten solder, a circuit board conveying means for conveying a circuit board along a conveying path formed above the solder accommodating means, and a melting accommodating means accommodated in the solder accommodating means. And an injection means for injecting the solder, wherein the injection means is formed to be inclined at a first angle with respect to a horizontal plane, and to be inclined at a second angle with respect to the transport direction of the circuit board. Multiple first
A plurality of nozzle holes formed by being inclined at the first angle with respect to the horizontal plane and at a third angle different from the second angle with respect to the transport direction of the circuit board. A jet type soldering apparatus comprising a second nozzle hole. 2. The jet type soldering apparatus according to claim 1, wherein a row is formed by each of the first and second nozzle holes. 3. The jet-type soldering apparatus according to claim 2, wherein each of the rows extends in a direction perpendicular to a direction in which the circuit board is transported. 4. The jet-type soldering apparatus according to claim 1, wherein the first angle is set on a front side in a conveying direction of the circuit board. 5. The circuit according to claim 1, wherein the second angle is set on the left side in the forward direction of the circuit board, and the third angle is set on the right side in the forward direction of the circuit board. Item 2. A jet type soldering apparatus according to Item 1. 6. A plurality of first nozzle holes formed to be inclined at a first angle with respect to a horizontal plane and at a second angle with respect to the transport direction of the circuit board; A plurality of second nozzle holes formed to be inclined at the first angle, and to be inclined at a third angle different from the second angle with respect to the transport direction of the circuit board. A nozzle comprising: