JP3495686B2 - Linear motor, manufacturing method thereof, electromagnetic pump and soldering device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motor having a unique cooling structure, a manufacturing method thereof, an electromagnetic pump and a soldering device.

[0002]

2. Description of the Related Art In Japanese Laid-Open Patent Publication No. 2-31628, a primary iron core having coils fitted in a plurality of slots formed in a comb shape on an upper surface is installed along a bottom surface of a solder bath. An electromagnetic pump with a passage of molten solder at the bottom of the solder bath along the primary iron core and a back iron through this passage is provided, and a molten solder flow is generated in the passage by the principle of a linear motor. There is described a soldering device (also referred to as a brazing device) in which molten solder is jetted from a nozzle communicating with a passage and the molten solder is brought into contact with a work.

This electromagnetic pump needs to be sufficiently cooled because it generates Joule heat from itself and is also affected by heat from a high temperature solder bath. The above publication discloses a structure for cooling the primary iron core and the coil by guiding the cooling air supplied from the cooling fan into each slot of the primary iron core.

[0004]

As described above, the prior art is as follows.
Since the structure is such that the cooling air is guided to each slot of the primary side iron core, there is a problem that the cooling structure portion becomes very large. In particular, it is necessary to secure a sufficient space on the cooling air supply side from the cooling fan to each slot, and it is difficult to downsize this cooling structure.

Further, conventionally, since the entire coil is located on the high temperature solder bath side, the coil is easily affected by the heat of the solder bath, and the cooling air passes through the coil surface, so that the cooling efficiency is not good. .

The present invention has been made in view of the above circumstances, and is a linear motor having a small and efficient cooling structure,
It is an object of the present invention to provide a manufacturing method, an electromagnetic pump, and a soldering device.

[0007]

Means for Solving the Problems The invention described in claim 1 includes a primary iron core in which a plurality of slots are provided on one side surface,, respectively Re each slot Niso the primary core of this fitting Wearing endless winding unit and each winding unit on the primary side iron core
By inserting it into the slot on one side of the
An empty space created inside each winding unit on the other side.
The winding unit fits inside each slot.
It stabilizes the condition and the slot of the primary side iron core is provided.
The heat of the primary side core is conducted by being closely adhered to the surface not covered
Has an opening on at least one side
A linear motor having a hollow body for cooling and a secondary side conductor arranged parallel to the slot side surface of the primary side core, and each winding unit having a primary side core
The other side of the primary core by fitting in the slot on the side
On the surface side, an empty space is created inside each winding unit.
Therefore, the empty space of each winding unit can be effectively used.
Use this to fit a hollow body for cooling and
By fitting the body, fitting of the winding unit in each slot
Stabilize the state, and further, install a cooling hollow body compactly inside each winding unit along the primary side iron core,
By passing a cooling fluid inside the hollow body, the primary side iron core and each winding unit are efficiently cooled from the inside,
Particularly, the primary core is a hollow body cooled by a cooling fluid.
The heat of the closely adhered primary side core
Provide a linear motor that can be cooled efficiently and has heat resistance.

The invention described in claim 2 is a linear motor in which the winding unit according to claim 1 comprises a coil bobbin endlessly formed of an insulating material and a coil wound around the coil bobbin. The coil bobbin that enables automatic winding of the coil facilitates formation of the winding unit.

The invention described in claim 3 is a linear motor in which the relationship between the slots of the primary iron core and the winding unit according to claim 2 is concentrated winding, and the primary winding is performed by this concentrated winding. The space factor of the coil cross-sectional area of the winding unit with respect to each slot cross-sectional area of the side iron core is increased.

According to a fourth aspect of the present invention, an endless winding unit is fitted to a primary side iron core having a plurality of slots on one side surface from the end of the primary side iron core, and the winding unit is formed. By fitting the coil into the slot of the primary side core, an empty space is provided inside the winding unit on the other side surface of the primary side core, and the winding unit is fitted into the slot of the primary side core. A hollow body for cooling having an opening on at least one side surface is fitted into an empty space of each winding unit formed by forming a slot, and a secondary side conductor is provided on the slot side surface of the primary side iron core. A method of manufacturing linear motors arranged in parallel, and by mounting each winding unit in a slot on one side surface of a primary side iron core,
Since an empty space is created inside each winding unit on the other side of the secondary iron core, the empty space of each winding unit is effectively used to fit the hollow body for cooling and The fitting stabilizes the fitting state of the winding unit in each slot.

[0011] The invention described in claim 5, the primary core having a plurality of slots are provided on one side, this primary core endless that each slot Niso respectively fitted in The winding unit and each winding unit are slotted on one side of the primary core.
Each side on the other side of the primary iron core
Fit in the empty space created inside the winding unit
Stabilize the fitting state of the winding unit in each slot
Together with the side of the side where the slot of the primary side core is not provided
It is closely attached to the surface so that the heat of the primary core can be conducted.
Cooling medium having an opening on at least one side for cooling
A hollow body, a non-magnetic plate that is in contact with the slot-side surface of the primary-side iron core, and a conductive fluid as a secondary-side conductor formed on the opposite side of the primary-side iron core through this non-magnetic plate. a solenoid pump; and a passageway, and primary each winding unit
Primary side by fitting into the slot on one side of the side iron core
Place an empty space inside each winding unit on the other side of the iron core.
Space is created for each winding unit.
It is possible to fit a hollow body for cooling by effectively using
In addition, by fitting this hollow body, the winding unit in each slot can be
Stabilize the fit of the knit, and further pass the cooling fluid through the compact hollow body that is installed inside each winding unit along the primary side iron core, and Cools efficiently , especially the primary core
Is attached to a hollow body cooled by a cooling fluid.
By efficiently conducting the heat of the secondary iron core to cool it, it is possible to deal with the case where the electromagnetic pump handles a high temperature conductive fluid.

According to a sixth aspect of the present invention, in the electromagnetic pump according to the fifth aspect, a back iron is arranged on the opposite side of the non-magnetic plate through the passage of the conductive fluid, and Since the primary side iron core and the back iron form a clear magnetic path through the passage, a force for transferring the conductive fluid in the passage can be efficiently obtained.

According to a seventh aspect of the present invention, there is provided a solder bath formed of a non-magnetic plate containing molten solder as a conductive fluid, and the electromagnetic bath according to the fifth or sixth aspect installed along the solder bath. A soldering apparatus comprising a pump and a nozzle for jetting the molten solder pumped up by this electromagnetic pump above the solder surface, and a hollow body compactly incorporated inside the winding unit,
The winding unit and the primary iron core whose temperature has risen due to heat radiation from the solder bath and its own Joule heat are efficiently cooled from the inside, and soldering is performed by a molten solder wave jetted from a nozzle by a stable electromagnetic pump action.

According to an eighth aspect of the present invention, in the soldering apparatus according to the seventh aspect, the primary side iron core, the hollow body for cooling, and the passage of the molten solder are provided along the longitudinal side plate of the solder bath. The cooling hollow body, which is provided in the vertical direction, has the lower end and the upper end opened, and the vertical passage directly gives an upward thrust to the molten solder in the passage so that the molten solder is directly discharged from the nozzle. Efficiently jets the air in the hollow body by natural convection due to the chimney effect of the hollow body in the vertical direction, sucks the outside air whose temperature is lower than the lower end of the hollow body, and conducts heat from the solder bath and windings. The air in the hollow body whose temperature has risen due to the Joule heat generated in the unit is discharged from the upper end. Further, the surface of the winding unit located on the side opposite to the solder bath naturally radiates heat without being affected by the heat of the solder bath.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a linear motor 11, in which a plurality of slots 13 and teeth 14 are alternately provided on one side surface of a straight primary iron core 12 formed by laminating a large number of thin iron plates. A cooling yoke 15, which is a hollow body for cooling, is abutted on the surface of the primary side iron core 12 on which the slots 13 and the like are not provided, and at each slot 13 of the primary side iron core 12. 1
Endless winding units 16 are fitted around the secondary iron core 12 and the cooling yoke 15, respectively.

Further, on the slot side surface of the primary side iron core 12, a movable iron core 17 as a secondary side conductor is arranged in parallel via an air gap. The movable iron core 17 includes a non-magnetic conductor plate 17a located on the side facing the primary iron core 12,
It has a magnetic conductor plate 17b such as an iron plate located on the opposite side.

The cooling yoke 15 has a flow passage 21 for a cooling fluid therein and has an opening 22 on at least one side surface. In FIG. 1, the cooling yoke 15 has an opening on the entire surface opposite to the primary core 12. A non-magnetic material such as stainless steel having a U-shaped cross-section provided with the portion 22 is closely attached back to back to the primary iron core 12.
The opening of the cooling yoke 15 may be formed by forming a hole or the like on the other surface of the cooling yoke 15.

The winding unit 16 includes a coil bobbin 23 having a U-shaped cross section and formed into an endless quadrangular shape by an insulating material such as synthetic resin, and a coil wound around the coil bobbin 23.
The coil 24 is wound around the coil bobbin 23 by an automatic winding machine or the like. Each winding unit
The same 16 is prepared in advance, and is assembled in the primary iron core 12 as described later.

The relationship between the slot 13 of the primary iron core 12 and the winding unit 16 is a concentrated winding in which one winding unit 16 is mounted only in one slot 13.

Then, 3 is added to the coil 24 of each winding unit 16.
When the phase alternating current is supplied, a moving magnetic field is generated through each tooth 14 of the primary side iron core 12, and the movable iron core 17 arranged in parallel with each tooth 14 of the primary side iron core 12 through an air gap is shown in FIG. A vertical thrust is generated and the movable iron core 17 is moved upward or downward.

At this time, a cooling yoke compactly assembled inside each winding unit 16 along the primary iron core 12
By supplying the cooling fluid containing room temperature air to the flow passage 21 inside the 15, the primary side iron core 12 and each winding unit 16 are efficiently cooled from the inside, and a linear motor having heat resistance is provided.

In the illustrated example, the primary side iron core 12 is cooled by conducting the heat of the primary side iron core 12 to the cooling yoke 15 cooled by the cooling fluid, and each winding unit 16 is cooled.
Cools by directly spraying a cooling fluid.

Further, the coil bobbin 23 capable of automatically winding the coil 24 facilitates formation of the winding unit 16.
Further, the concentrated winding can increase the space factor, which is the ratio of the coil cross-sectional area of the winding unit 16 to each slot cross-sectional area of the primary side iron core 12, and as the number of coil turns increases, it becomes more Large thrust can be obtained.

Next, FIG. 2 shows an embodiment of a method of manufacturing the linear motor 11, in which the hollow portion 25 of the winding unit 16 is attached to the primary side iron core 12 at the end of the primary side iron core 12. By further fitting (arrow A) and fitting the winding unit 16 into the slot 13 provided on one side surface of the primary iron core 12 (arrow B), the winding unit 16 is attached to the other side surface of the primary iron core 12. A free space 25a is provided inside the winding unit 16, and the winding unit 16 is fitted into the slot 13 of the primary side iron core 12 in each slot 13.
The primary side is provided by fitting the cooling yoke 15 into the vacant spaces 25a of the winding units 16 formed by the above. Furthermore, the primary core
Movable iron core as a secondary side conductor for the 12 slot side surface
Place 17 (Figure 1) in parallel.

As described above, by inserting each winding unit 16 into the slot 13 on one side of the primary side iron core 12, an empty space is provided inside each winding unit 16 on the other side of the primary side iron core 12. Since 25a is produced, the empty space 25a of each winding unit 16 is effectively used to fit the cooling yoke 15, and by fitting the cooling yoke 15,
The fitting state of the winding unit 16 in each slot 13 is stabilized.

Next, FIGS. 3 and 4 show the linear motor 11
Another embodiment of is shown. The same parts as those in the embodiment shown in FIGS. 1 and 2 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 3, the cooling yoke is
A non-magnetic plate 26 such as a stainless steel plate is brought into contact with the teeth 14 of the primary side iron core 12 in which 15 is incorporated, and an air gap 27 is provided through the non-magnetic plate 26 to the opposite side of the primary side iron core 12. And a movable iron core 17 as a secondary conductor is arranged.

FIG. 4 shows the primary side of the linear motor 11 shown in FIG. 3, and two rows of primary side iron cores 12 are provided side by side with the primary side iron core 12 shown in FIG. Although different in points, each primary iron core 12 has a plurality of slots on one side surface of the primary iron core 12.
13 and teeth 14 are alternately provided, and a cooling yoke 15 is closely attached back to back to the surface of the primary side iron core 12 on the side where the slots 13 are not provided. The structure in which endless winding units 16 are fitted around the side iron core 12 and the cooling yoke 15 is similar to that of FIG.

The winding unit 16 includes a coil bobbin 23 having an endless shape and made of an insulating material and having a concave cross section, and a coil 24 wound around the coil bobbin 23. The primary side iron core 12 The relationship between the slot 13 and the winding unit 16 is similar to that in FIG. 1 in that the single winding unit 16 is mounted only in the single slot 13.

Then, the coil 24 of each winding unit 16 has 3
When a phase alternating current is supplied to generate a moving magnetic field, the non-magnetic plate 26
And movable iron cores 17 arranged in parallel via an air gap 27
The thrust in the longitudinal direction of the movable core 17
17 is moved in that direction.

At this time, a cooling yoke compactly assembled inside each winding unit 16 along the primary iron core 12
By supplying a cooling fluid containing room temperature air to the inside of the core 15, the primary side iron core 12 and each winding unit 16 can be efficiently cooled from the inside.

Next, FIG. 5 shows an embodiment of an electromagnetic pump 31 using the principle of the linear motor 11 and a soldering device 32 using the electromagnetic pump 31, which is a non-magnetic plate such as a stainless steel plate. The formed solder bath 33 contains the molten solder 34 as a conductive fluid, and the electromagnetic pump 31 is provided on the outer surface of the side plate 35 along a vertical side plate 35 as a non-magnetic plate forming the solder bath 33. The primary side iron core 12 on which the cooling yoke 15 and each winding unit 16 are mounted is brought into contact with the inside of the side plate 35 along the primary side iron core 12 with a conductive fluid as a secondary side conductor. Passage 36 for some molten solder 34a
Is formed, the back iron 37 is installed in parallel inside the solder bath 33 through this passage 36, the suction port 38 is opened at the lower end of the passage 36, and the discharge port 39 is opened at the upper end. .

A nozzle 41 for jetting the molten solder 34a upward from the solder surface is communicated with the discharge port 39 of the electromagnetic pump 31 to form a soldering device. Inside the nozzle 41, a current plate 42 formed by forming a large number of small holes is provided.

The electromagnetic pump 31 of this soldering device 32 is
Primary side iron core 12, cooling yoke 15, passage 3 for molten solder 34a
6 and a back iron 37 are provided in the vertical direction along the vertical side plate 35 of the solder bath 33, and the cooling yoke 15 is also provided.
Is internally provided with a cooling fluid channel 21 in the longitudinal direction, an opening 22 is provided on a side surface opposite to the primary core 12, and the primary core 12 is closely attached back to back. And the upper end is open.

Then, the teeth 14 of the primary side iron core 12 having the cooling yoke 15 incorporated therein are brought into contact with the outer surface of the side plate 35 of the solder bath 33, and the passage 36 of the molten solder 34a is formed inside the side plate 35. Since the back iron 37 is arranged via the back iron 37, the three-phase alternating current is supplied to the coil of each winding unit 16, each tooth 14 of the primary iron core 12, the passage 36 of the molten solder 34a, and the back iron 3
When a moving magnetic field passing through 7 is generated, an upward thrust is generated in the molten solder 34a in the passage 36, the molten solder 34a pumped up in the passage 36 is jetted from the nozzle 41, and a work 43 such as a component mounting board is produced. Be soldered to.

At this time, a cooling yoke compactly assembled inside each winding unit 16 along the primary iron core 12.
When a cooling fluid such as cold air is naturally or forcibly passed through 15, the primary side iron core 12 and each winding unit 16 whose temperature has risen due to heat dissipation from the solder bath 33 and its own Joule heat are efficiently transferred from inside. Can cool well.

In particular, due to the chimney effect of the cooling yoke 15 in the vertical direction, the air in the flow passage 21 of the cooling yoke 15 rises by natural convection even if no forced cooling means is provided.
While sucking in outside air of lower temperature from the lower end opening 45 of 21,
Air in the cooling yoke 15 whose temperature has risen due to heat conduction from the solder bath 33 and Joule heat generated from the winding unit 16 can be discharged from the upper end opening 46 of the flow path 21.

In addition, the outer surface 47 of each winding unit 16 located on the opposite side of the solder bath 33 can radiate heat naturally without being affected by the heat of the solder bath 33.

With this, the electromagnetic pump 31 can handle the high temperature molten solder 34a, and the stable electromagnetic pump action causes the molten solder wave 34b having a stable wave height to be jetted from the nozzle 41, which enables good soldering. .

Further, the passage 36 in the longitudinal direction allows the passage
It is possible to directly apply an upward thrust to the molten solder 34a in the 36 so that the nozzle 41 can efficiently jet the molten solder 34a.

Since the moving magnetic field is applied to the molten solder 34a in the passage 36 by the primary iron core 12 and the back iron 37, the thrust by the principle of the linear motor is efficiently applied to the molten solder 34a in the passage 36. It can be generated well.

Although the primary side is the fixed side and the secondary side conductor is the movable side in the illustrated embodiment, this relationship may be reversed, and the primary side is the movable side and the secondary side. The conductor may be the fixed side.

[0044]

According to the invention described in claim 1, each winding unit is
Fitting the knit into the slot on one side of the primary core
Inside of each winding unit on the other side of the primary core
Since an empty space is created in each of the winding units,
Fits a hollow body for cooling by effectively utilizing the empty space
This hollow body fits into each slot.
The fitting state of the winding unit inside can be stabilized, and further,
A cooling hollow body can be compactly installed inside each winding unit along the primary side iron core, and a cooling fluid is passed through the inside of this hollow body so that the primary side iron core and each winding unit are Can cool efficiently, especially on the primary side
The iron core is closely attached to the hollow body cooled by the cooling fluid.
The heat of the primary iron core is conducted so that it can be cooled efficiently.
Can retirement, it is possible to provide a linear motor having a heat resistance.

According to the second aspect of the invention, the winding unit can be easily formed by the coil bobbin capable of automatically winding the coil.

According to the third aspect of the invention, since the relationship between the slots of the primary side core and the winding unit is concentrated winding, the coil cross-sectional area of the winding unit with respect to each slot cross-sectional area of the primary side core. The space factor can be increased, that is, a larger thrust can be obtained with the same current as the number of coil turns increases.

According to the invention described in claim 4, by fitting each winding unit into the slot on one side surface of the primary side iron core, an empty space is provided inside each winding unit on the other side surface side of the primary side iron core. Since the empty space of each winding unit is effectively used, a hollow body for cooling can be fitted, and the fitting of the hollow body allows the winding unit to be fitted in each slot. Can be stabilized.

According to the invention of claim 5, each winding unit
Fitting the knit into the slot on one side of the primary core
Inside of each winding unit on the other side of the primary core
Since an empty space is created in each of the winding units,
Fits a hollow body for cooling by effectively utilizing the empty space
This hollow body fits into each slot.
The fitting state of the winding unit inside can be stabilized, and further,
By passing a cooling fluid through a compact hollow body built inside each winding unit along the primary iron core, the primary iron core and each winding unit are efficiently cooled from the inside ,
The primary core is a hollow body cooled by a cooling fluid
The heat of the closely adhered primary side core
By efficiently cooling with a non-magnetic plate, it is possible to cope with an electromagnetic pump in which a high-temperature conductive fluid is caused to flow in a passage formed through a non-magnetic plate.

According to the sixth aspect of the invention, since a clear magnetic path passing through the passage is formed by the primary iron core and the back iron, the transfer force is efficiently applied to the conductive fluid in the passage. be able to.

According to the invention of claim 7, the winding unit and the primary iron core whose temperature is raised by the heat radiation from the solder bath and the Joule heat of itself by the hollow body compactly incorporated in the winding unit. Can be efficiently cooled from the inside, and stable soldering can be performed by the molten solder wave jetted from the nozzle by the stable electromagnetic pump action.

According to the eighth aspect of the present invention, the vertical passage directly applies an upward thrust to the molten solder in the passage so that the molten solder can be efficiently jetted from the nozzle. Also, due to the chimney effect of the hollow body in the vertical direction, the air in this hollow body can be raised by natural convection, sucking the outside air whose temperature is lower than the lower end of the hollow body, and conducting heat from the solder bath and the winding unit. The air in the hollow body whose temperature has risen due to the generated Joule heat can be naturally discharged from the upper end. Further, from the surface of the winding unit opposite to the solder bath, natural heat can be released without being affected by the heat of the solder bath.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a linear motor according to the present invention.

FIG. 2 is a perspective view showing an embodiment of a method for manufacturing a linear motor according to the present invention.

FIG. 3 is a perspective view showing another embodiment of the above linear motor.

FIG. 4 is a perspective view showing a primary side of the linear motor shown in FIG.

FIG. 5 is a perspective view showing an embodiment of an electromagnetic pump and a soldering device according to the present invention.

[Explanation of symbols]

11 Linear motor 12 Primary iron core 13 Slot 15 Cooling yoke 16 as hollow body 16 Winding unit 17 Movable iron core as secondary conductor 22 Opening 23 Coil bobbin 24 Coil 25a Free space 31 Electromagnetic pump 32 Soldering device 33 Solder Bath 34 Molten solder as conductive fluid 34a Molten solder as secondary conductor or as conductive fluid 35 Vertical side plate as non-magnetic plate 36 Passage 37 Back iron 41 Nozzle

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-243698 (JP, A) JP-A-10-156527 (JP, A) JP-A-11-104817 (JP, A) Actual development Sho 62- 165775 (JP, U) Japanese Patent Publication No. 2-31628 (JP, B2) Jikkō 50-31846 (JP, Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02K 44/00 H02K 41 / 00 B23K 1/08 H05K 3/34

Claims (8)

(57) [Claims] 1. A device provided with a plurality of slots on one side thereof.
Fitting the following side core, an endless winding units each slot Niso respectively fitted in the primary side core of this, the windings unit on one side of the slot of the primary core
By doing so, each winding unit on the other side of the primary side core
Each slot that fits into the empty space created inside
Stabilize the fitting state of the winding unit inside
Adhere closely to the surface of the secondary iron core where the slot is not provided.
The primary side iron core is cooled by conducting the heat through it.
A cooling hollow body having an opening on at least one side surface, and a cooling hollow body arranged parallel to the slot side surface of the primary core 2
A linear motor having a secondary conductor. 2. The linear motor according to claim 1, wherein the winding unit includes an endless coil bobbin made of an insulating material and a coil wound around the coil bobbin. 3. The linear motor according to claim 2, wherein the relationship between the slot of the primary side iron core and the winding unit is concentrated winding. 4. A device provided with a plurality of slots on one side thereof.
An endless winding unit is fitted to the secondary iron core from the end of the primary iron core, and this winding unit is fitted in a slot of the primary iron core to wind it on the other side of the primary iron core. An empty space is provided inside the wire unit, and the empty space of each winding unit formed by fitting the winding unit to the slot of the primary side iron core has an opening on at least one side surface. A method for manufacturing a linear motor, characterized in that a hollow body for cooling is fitted and a secondary side conductor is arranged in parallel with a slot side surface of the primary side iron core. 5. A slot having a plurality of slots on one side thereof.
Fitting the following side core, an endless winding units each slot Niso respectively fitted in the primary side core of this, the windings unit on one side of the slot of the primary core
By doing so, each winding unit on the other side of the primary side core
Each slot that fits into the empty space created inside
Stabilize the fitting state of the winding unit inside
Adhere closely to the surface of the secondary iron core where the slot is not provided.
The primary side iron core is cooled by conducting the heat through it.
A cooling hollow body having an opening on at least one side surface, a non-magnetic plate in contact with the slot side surface of the primary side iron core, and a non-magnetic plate on the side opposite to the primary side iron core via this non-magnetic plate. An electromagnetic pump comprising a passage for a conductive fluid formed as a secondary conductor. 6. The electromagnetic pump according to claim 5, further comprising a back iron arranged on the opposite side of the non-magnetic plate via a passage of the conductive fluid. 7. A solder bath formed of a non-magnetic plate containing a molten solder as a conductive fluid, an electromagnetic pump according to claim 5 or 6 installed along the solder bath, and a pumping by this electromagnetic pump. A soldering device, comprising: a nozzle for jetting the molten solder thus obtained above a solder surface. 8. A primary side iron core, a hollow body for cooling, and a passage for molten solder are provided in a vertical direction along a vertical side plate of a solder bath, and a hollow body for cooling has a lower end and an upper end opened. The soldering device according to claim 7, wherein the soldering device is formed.