JP2003205364A - Soldering equipment - Google Patents

Abstract

(57) [Problem] To provide a soldering apparatus capable of easily using a solder having a high melting point by improving a heat balance. SOLUTION: The soldering apparatus of the present invention comprises: a solder tank 30 for storing a solder material 2 in a molten state; and a solder material 2 immersed in the solder tank 30 at a liquid level or lower.
And a nozzle 32 for discharging the solder material 2 to the soldering target. Since heat generated by driving the electromagnetic pump 1 is efficiently transmitted to the solder material 2, a solder material having a high melting point can be easily melted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soldering apparatus for ejecting a molten solder which is pressurized from a nozzle to perform a soldering operation on, for example, the back surface of a printed circuit board.

[0002]

2. Description of the Related Art Generally, a soldering device is known as a device for soldering a lead wire of an electric component mounted on a printed circuit board to a circuit pattern. On the other hand, since solder is a conductive fluid, it can be driven by an electromagnetic pump. Therefore, for example, JP-A-58-122170
As can be seen in the publication, a soldering device has been developed which uses an electromagnetic pump to flow solder and perform soldering.

In an electromagnetic pump in a soldering apparatus equipped with such a conventional electromagnetic pump, a part of an iron core of the electromagnetic pump and an outer duct which is a flow path for the molten solder are installed in a solder bath. Other electromagnetic coils,
The stator including the iron core and the stator support structure are installed under the solder bath. Then, due to the electromagnetic force generated by energizing the coil, the solder moves in the space inside the solder bath and is ejected from the nozzle onto the printed circuit board.

[0004]

In such a conventional soldering apparatus, heat acting on the coil of the electromagnetic pump includes heat of the solder melted by using the heater and heat generated by Joule heat generation of the coil itself. It becomes a thing. Therefore, cooling equipment such as a fan is indispensable from the viewpoint of heat resistance of the coil.

From the viewpoint of environmental problems, there is an increasing need for lead-free solder (for example, tin-silver-copper alloy) in place of conventional lead-tin solder. When lead-free solder is used, it is estimated that the melting temperature will rise by about 50 ° C from the current temperature of about 200 ° C. As the melting temperature rises, the coil temperature of the electromagnetic pump also rises.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a soldering apparatus capable of easily utilizing solder having a high melting point by improving heat balance.

[0007]

In order to achieve the above object, the present invention provides a solder bath for storing a molten solder material, and a state of being immersed below the liquid level of the solder material in the solder bath. The present invention provides a soldering device having an electromagnetic pump that electromagnetically flows the solder material and a nozzle that discharges the solder material onto an object to be soldered.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The details of the present invention will be described below with reference to the illustrated embodiments. The same components are denoted by the same reference symbols throughout the drawings.

A first embodiment of a soldering apparatus according to the present invention will be described with reference to FIGS. 1, 2, 3 and 4.

FIG. 1 is a soldering apparatus 1 according to this embodiment.
00 is a block diagram schematically showing the same, and FIG. 2 is an annular linear type (ALIP) installed in the soldering apparatus according to the present embodiment.
(Type) electromagnetic perspective pump is a partially cutaway perspective sectional view, FIG.
FIG. 4 is a cross-sectional view in the radial direction of FIG. 4, and FIG. 4 is a schematic view showing how the inner duct of the electromagnetic pump is removed.

First, the flow of molten solder will be described. In FIG. 1, a solder bath 30 contains, for example, lead-free molten solder 2. Further, it is heated by a general heater (not shown). In the solder bath 30, the ALIP type electromagnetic pump 1 is installed by being immersed below the liquid level of the molten solder 2.

The ring 21 is used for pulling out an inner duct 4 which will be described later at the time of overhaul, and is constructed to be removable. The cable 39 also supplies electric power to the electromagnetic pump 1.

As shown in FIGS. 2 and 3, the electromagnetic pump 1 is provided with an outer duct 3. The outer duct 3 has a molten solder inlet 10 for sucking the molten solder 2 and a molten solder outlet 11 for discharging the molten solder 2 at both ends thereof. Further, the outer duct 3 and the inner duct 4 form a double annular flow passage 5 of a double pipe structure concentric along the central axis of the electromagnetic pump 1. The flow path is formed so that the molten solder 2 sucked from the solder inlet 10 moves in the annular flow path 5 and flows out from the molten solder outlet 11. In addition,
Since the plurality of projections 4 a provided on the inner duct 4 are provided on the outer duct 3, the positional relationship between the outer duct 3 and the inner duct 4, that is, the cross-sectional shape of the annular flow path 5 is kept constant.

The molten solder outlet 11 allows the molten solder 2 to flow to the nozzle 32 through the pipe 31. A soldering target 33 such as a printed circuit board is arranged above the nozzle 32. The nozzle 32 is provided with a plurality of holes (not shown), and the jet solder 2a is applied to the soldering target 33.
Is discharged.

The excess molten solder 1 from the nozzle 32 overflows from the nozzle 32 and is returned to the solder bath 30 for reuse.

Next, the structure of the electromagnetic pump will be described in detail. As shown in FIGS. 2 and 3, on the outside of the outer duct 3, an outer iron core (first
Iron cores) 6 are arranged in the circumferential direction.

The void portion of the outer iron core 6 is a plurality of slots 7 formed in parallel, and an annular outer electromagnetic coil 8 is arranged in each of the plurality of slots 7 in the axial direction of the outer duct 3. . The outer electromagnetic coil 8 is connected so that a three-phase alternating current flows and creates a traveling magnetic field.

An inner iron core (second iron core) 9 is arranged in the inner duct 4. The outer iron core 6 and the inner iron core 9 have a function of giving a traveling magnetic field and radiating coil heat or Joule heat generated inside the electromagnetic pump 1 to the molten solder 2.

Although not shown here, the outer iron core 6 has end plates provided at both ends in the circumferential direction of a plurality of laminated electromagnetic steel plates, and the electromagnetic steel plates are inserted into holes provided in the outer iron core 6 in the circumferential direction. The structure may be such that it is fixed by a fixed fixture.

The outer side of the outer iron core 6 is enclosed and surrounded by a casing 12. A support structure (not shown) is arranged in the casing 12, and each outer core 6
Is cantilevered. Therefore, the outer core 6 can be supported by the support structure so as to be pressed against the outer duct 3.

The material of the outer duct 3 and the casing 12 is a non-magnetic material, which is resistant to corrosion by the molten solder 2 and flux and has sufficient strength at high temperature. The outer core 6 and the inner core 9 are made of a ferromagnetic material.

The outer electromagnetic coil 8 is constructed by combining a conductor and an insulating material, and the conductor and the insulating material are the molten solder 2
A material that does not easily deteriorate in a high temperature environment due to the temperature (for example, 250 ° C. or higher) and Joule heat of the coil is applied.

When cleaning the inside of the electromagnetic pump 1,
This is performed as shown in FIG. That is, the ring 21 is attached to the upper end of the inner duct 4 near the molten solder inlet 10. Then, the inner duct 4 in the outer duct 3 can be taken out by lifting the ring 21. This facilitates removal of the solder oxide adhering to the surfaces of the outer duct 3 and the inner duct 4 forming the annular flow path 5.

Here, the shape of the inner duct 4 is changed to the solder bath 3
The shape may be such that it projects upward from the liquid surface of the molten solder 2 in 0. By attaching the ring 21 to the protruding portion thereof, it is possible to easily pull out and maintain the inner duct 4.

Further, by making the weight of the inner duct 4 lighter than the specific gravity of the molten solder 2, the inner duct 4 can be easily pulled out.

In order to keep the cross-sectional shape of the annular flow path 5 constant, the inner duct 4 may be constructed as shown in FIG. 5 instead of being provided with a plurality of projections 4a. FIG. 5 is a cross-sectional view showing a connecting portion between the inner duct 4 and the outer duct 3. The end of the inner duct 4 on the molten solder inlet side extends from the outer duct 3 to the upper surface and is joined to the flat plate 23. Further, the flat plate 23 is engaged with the outer duct 3 by using the lock mechanism 22. The lock mechanism 22 includes a hook-shaped member 24 attached to the flat plate 23 and a hook-shaped member 25 attached to the end portion of the outer duct 3.

FIG. 6 is a partially enlarged perspective view of the lock mechanism 22 in FIG. A hook hole 26 is provided in the hook member 24 attached to the flat plate 23, and a hook 27 is provided in the hook member 25 attached to the outer duct 3. Then, by rotating the flat plate 23 and inserting the hook claw 27 into the hook hole 26, both are engaged and locked.

When the locking mechanism 22 is engaged, a downward force is applied to the inner duct 4 so that the inner duct 4 is pressed against the outer duct 3 via the flange 28 joined to its periphery.
On the other hand, in the solder bath 30, buoyancy acts on the inner duct 4 and upward force is applied. This balance of forces maintains the lock.

The molten solder 2 passes through a plurality of holes 29 formed in the flange 28 and flows into the annular flow path 5.

Then, as shown in FIG. 4, the outer duct 3
When removing the inner duct 4 from the inside, the flat plate 23 may be reversely rotated to release the engagement. This work can be done very easily.

According to the soldering apparatus 100 according to the embodiment of the present invention configured as described above, the electromagnetic pump 1 is immersed in the molten solder 2 in the solder bath 30 to generate internal heat of the electromagnetic pump 1. Heat can be applied to the molten solder. As a result, the temperature of the molten solder can be increased more than that of the conventional device, and the capacity of the molten heater in the solder bath 30 can be reduced.

This is extremely suitable for applying a lead-free solder material having a melting point of about 50 ° C. higher than that of the conventional lead-tin solder.

When applying a lead-free solder material, it is necessary to consider the heat resistance of the insulating material of the outer electromagnetic coil 8 of the electromagnetic pump. Therefore, it is preferable to use an insulating material having a heat resistance far higher than the melting point of the lead-free solder material for the coil insulating material of the electromagnetic pump in the present embodiment. Thereby, the heat generated in the outer electromagnetic coil 8 can be radiated to the molten solder in the annular flow path 5 through the outer iron core 6, so that a cooling device such as a fan for cooling the inside of the casing 12 can be omitted.

When the electromagnetic pump 1 is an annular linear type electromagnetic pump, the inner duct 4 can be pulled upward from the electromagnetic pump 1 as shown in FIG. Therefore, maintenance for removing the solder oxide adhering to the outer duct 3 and the inner duct 4 forming the annular flow path 5 through which the molten solder 2 flows becomes easy. Since the adhesion of the solder oxide is reduced, the uniformity of the flow path width is maintained, and the variation of the height of the solder 2 in the solder bath 30 can be reduced.

Of course, as long as the electromagnetic pump 1 is immersed in the solder bath 30, the electromagnetic pump 1 may be arranged in any state, for example, it may be arranged horizontally or inclined.

Next, a second embodiment of the soldering apparatus according to the present invention will be described with reference to FIGS. 7 and 8A and 8B. In this embodiment, a flat linear type (FLIP type) electromagnetic pump 13 is used as shown in FIG. 7 in place of the annular rear type electromagnetic pump 1 in the first embodiment.

8 (a) and 8 (b) are perspective views showing only the main part of the stator of the FLIP type electromagnetic pump 13.

An electromagnetic pump 13 is dipped and installed below the liquid level of the molten solder 2 in the solder bath 30. A rectangular nozzle 35 is attached to the discharge side of the electromagnetic pump 13. The soldering object 33 is arranged on the upper portion of the rectangular nozzle 35.

The electromagnetic pump 13 is constructed as shown in FIG. That is, the outer plate (outer duct) 14 and the inner plate (inner duct) 15 formed by two flat plates facing each other are arranged in parallel, and the outer plate 1
The space sandwiched between 4 and the inner plate 15 becomes the molten solder flow path 16. The outer iron core 17 is arranged on the back surface of the outer plate 14, and the outer electromagnetic coil 18 is arranged in the slot of the outer iron core 17. An inner iron core 19 is arranged on the back surface of the inner plate 15. The outer electromagnetic coil 18 generates a traveling magnetic field by passing a three-phase alternating current.

Further, as shown in FIG. 8B, an inner iron core 19 is arranged on the back surface of the inner plate 15, and an electromagnetic coil 20 for flowing a three-phase alternating current is similarly arranged in the slot of the inner iron core 19. May be. 8A has a single stator structure, while FIG. 8B has a double stator structure.

The outer iron core 17 and the outer electromagnetic coil 18 are supported by a support structure, and the support structure is arranged in a casing 12 that seals the outside.

The outer plate 14, the inner plate 15 and the casing 12 are non-magnetic materials and are made of a material which is not easily corroded by the molten solder 2, flux or the like and has sufficient strength at high temperature.

The outer iron core 17 is made of a ferromagnetic material, and the outer electromagnetic coil 18 is a combination of a conductor and an insulating material. The conductor and the insulating material are in a high temperature environment due to the molten solder temperature (250 ° C.) and Joule heat generation of the coil. It is made of a material that does not easily deteriorate.

According to the present embodiment, as in the first embodiment, by immersing the electromagnetic pump 13 in the molten solder 2 in the solder bath 34, the internal heat generation of the electromagnetic pump 13 is prevented. Can be heated. Since the temperature of the molten solder can be increased by this, the solder bath 34
It is possible to reduce the capacity of the melting heater inside.

The electromagnetic pump 13 has a rectangular shape. Therefore, when the solder bath 30 is formed in a rectangular shape, it can be efficiently stored in the solder bath 30.

Instead of forming the outer plate 14 and the inner plate 15 with a pair of parallel flat plates, it is also possible to form a rectangular tubular duct whose longitudinal section in the direction perpendicular to the flow direction of the molten solder is rectangular. Even in the example, it is possible to obtain the same effect as that of the above-described embodiment.

Further, when the double stator structure is adopted as shown in FIG. 8B, the molten solder 2 is about 2 times as much as when the single stator structure is adopted as shown in FIG. 8A.
Double thrust can be generated.

Next, a third embodiment of the soldering apparatus according to the present invention will be described with reference to FIG. The present embodiment is based on the structure of the electromagnetic pump 1 in the first embodiment.

As shown in FIG. 9, a cylindrical flow skirt 37 is further attached to the flat plate 36 attached to the inner duct 4. That is, the upper outer peripheral surface of the casing 12 is surrounded by the gap 38 to regulate the flow of the molten solder 2. The axial length of the flow skirt 37 can be changed arbitrarily.

According to the present embodiment, the flat plate 36 and the flow skirt 37 can prevent the solder oxide floating on the molten solder liquid surface of the solder bath 30 from entering the flow path of the electromagnetic pump 1, and the maintenance work. The number of times can be reduced. Further, since it is difficult to take the solder oxide into the flow path of the electromagnetic pump 1, the liquid level fluctuation of the solder bath 30 is suppressed.

Next, a fourth embodiment of the soldering apparatus according to the present invention will be described with reference to FIG. In this embodiment, a helical (HIP type) electromagnetic pump is applied to a soldering device. The overall structure of the soldering device is the same as in the previous embodiment.

As shown in the figure, the helical electromagnetic pump 42 has a spiral groove 43 formed on the surface of the inner duct 4. The molten solder 2 is applied to the outer duct 3 and the inner duct 4
The space flows along the groove 43.

Inner electromagnetic coil 4 fixed to outer iron core 6
4, the winding direction of No. 4 differs from the annular linear type electromagnetic pump 1 shown in FIG. 2 by 90 degrees. This is for applying a circumferential electromagnetic driving force to the inner duct 4. Then, when the inner duct 4 rotates about the axis, the molten solder 2 can move along the spiral groove 43.

Even when such a helical type electromagnetic pump 42 is used, the same effect as when using another electromagnetic pump can be expected.

Next, a fifth embodiment of the soldering apparatus according to the present invention will be described with reference to FIGS. The present embodiment is a soldering device 300 in which two annular linear type (ALIP type) electromagnetic pumps 1 are housed in one casing 12 in the soldering device. The overall structure of the soldering device 300 is the same as that of the first embodiment.
With this structure, the driving force of the molten solder 2 can be doubled while sharing most of the constituent elements.

[0056]

According to the present invention, it is possible to realize a soldering apparatus which can easily use a solder having a high melting point by improving the heat balance.

[Brief description of drawings]

FIG. 1 is a configuration diagram schematically showing a soldering device according to a first embodiment of the present invention.

FIG. 2 is a perspective sectional view showing a partially cutaway view of an annular linear type (ALIP type) electromagnetic pump installed in the soldering apparatus according to the first embodiment.

FIG. 3 is a radial cross-sectional view of FIG.

FIG. 4 is a schematic view showing how the inner duct of the electromagnetic pump is removed.

FIG. 5 is a cross-sectional view showing a connecting portion between an inner duct and an outer duct in the first embodiment.

FIG. 6 is an enlarged partial perspective view of the lock mechanism in FIG.

FIG. 7 is a configuration diagram schematically showing a soldering device according to a second embodiment of the present invention.

FIG. 8 is a perspective view showing a main part of a stator of a FLIP type electromagnetic pump.

FIG. 9 is a sectional view showing an annular linear type electromagnetic pump used in a soldering apparatus according to a third embodiment of the present invention.

FIG. 10 is a sectional view showing a helical type (HIP type) electromagnetic pump used in a soldering apparatus according to a fourth embodiment of the present invention.

FIG. 11 is a sectional view showing a soldering device according to a fifth embodiment of the present invention.

FIG. 12 is another sectional view showing the soldering device according to the fifth embodiment of the present invention.

FIG. 13 is a sectional view showing an annular linear type electromagnetic pump used in a soldering device according to a fifth embodiment of the present invention.

[Explanation of symbols]

1. Annular linear type electromagnetic pump 2 ... Molten solder 3 ... Outer duct 4 inner duct (inner stator) 5 ... Circular flow path 6 ... Outer iron core (first iron core) 7 ... slot 8 ... Inside electromagnetic coil 9 ... Inner iron core (second iron core) 10 ... Molten solder inlet 11 ... Molten solder outlet 12 ... Casing 13 ... Flat linear type electromagnetic pump 14 ... Outer duct 15 ... Inside duct 16 ... Molten solder flow path 17 ... Outer iron core 18 ... Outer electromagnetic coil 19 ... Inner iron core 20 ... Inside electromagnetic coil 21 ... Ring 22 ... Lock mechanism 23 ... Flat plate 24 ... Flat plate side locking member 25 ... Key-shaped member 30 ... Solder bath 32 ... Nozzle 33 ... Soldering target 36 ... Flat plate 37 ... Flower skirt 42 ... Helical electromagnetic pump

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroaki Abe             8th Shinsugita Town, Isogo Ward, Yokohama City, Kanagawa Prefecture             Ceremony company Toshiba Yokohama office F-term (reference) 4E080 AA01 BA12 CA12                 5E319 AC01 CC24 GG20

Claims (13)

[Claims] 1. A solder bath for storing a molten solder material, an electromagnetic pump for electromagnetically flowing the solder material in a state of being immersed below a liquid level of the solder material in the solder bath, and the solder. A soldering device, comprising: a nozzle for discharging a material onto an object to be soldered; 2. The electromagnetic pump includes a casing, a flow path that penetrates the casing and allows a solder material to pass therethrough,
It has a 1st iron core arrange | positioned in the said casing and connected to this flow path, and the coil attached to the said iron core which makes an electromagnetic force act on the said flow path, and flows a solder material, It is characterized by the above-mentioned. The described soldering device. 3. The soldering apparatus according to claim 2, wherein the electromagnetic pump circulates the solder material in the solder bath by using an electromagnetic force acting on the flow path. 4. The flow path is formed in an annular shape in cross section and is covered with the first iron core, and a second iron core is inserted and arranged in the flow path. Soldering equipment. 5. The soldering apparatus according to claim 4, wherein the electromagnetic pump is an annular linear type electromagnetic pump. 6. The soldering apparatus according to claim 2, wherein the flow path is formed in a rectangular cross section and is sandwiched between the first iron cores. 7. The soldering device according to claim 6, wherein the electromagnetic pump is a flat linear type electromagnetic pump. 8. The flow channel is formed in an annular cross section and covered with the first iron core, a second iron core is inserted and arranged in the flow channel, and a groove is formed around the second iron core. The soldering device according to claim 2, wherein the soldering device is formed. 9. The soldering apparatus according to claim 8, wherein the electromagnetic pump is a helical type electromagnetic pump. 10. The soldering apparatus according to claim 4, wherein the second iron core can be pulled out from the flow path. 11. A lock mechanism for fixing the second iron core to the flow path.
The described soldering device. 12. The soldering device according to claim 1, wherein a flow skirt for restricting the flow of the solder material is provided near the flow path. 13. The soldering device according to claim 1, wherein the soldering device is for lead-free solder.