JP4283025B2 - Solder playback device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is mainly used in a solder recycling apparatus that regenerates solder from dross generated in a solder tank that solders a large number of electronic components mounted on a circuit board to the circuit board by dipping or flow soldering. Is.
[0002]
[Prior art]
In the above dip soldering method, the surface of the molten solder contained in the solder bath is always in contact with air, so that an oxide film is generated quickly, and the oxide film on the solder surface is removed by a scraping mechanism before the circuit board is immersed. Action is taken. Also, in the flow soldering method, the molten solder is jetted and the soldered surface of the circuit board is immersed in the solder. More than the law.
[0003]
The oxide generated in the molten solder does not float only with the complete oxide, but floats as a sherbet-like dross in which the oxide and the molten solder are mixed. At the soldering site, when a large amount of dross was generated in the solder tank, the dross was scooped out from the solder tank and stored in a container, which was discarded or handed over to a smelter.
[0004]
Since dross contains a large amount of solder that can still be used, it is desirable to effectively utilize only the solder taken out from the dross and reuse it, and as a means to realize this, the solder can be melted and held. A separation device is known in which dross is introduced onto molten solder accommodated in a container and stirred, and a separating agent is sprayed to promote separation of the solder from the oxide (see Patent Document 1).
[0005]
The separation device is a state in which dross is previously melted in a container provided with a heater therein, and dross is newly introduced into the container and stirred while spraying the dross separating agent. When the oxide residue is separated from the dross, the residue is scooped up with a net-like material, and then the regenerated solder is pumped out with a handle-like material to obtain a regenerated solder.
[0006]
[Patent Document 1]
JP 2002-331360 A (3rd to 4th pages, FIG. 2)
[0007]
[Problems to be solved by the invention]
In the above-described prior art, the container for storing the dross is provided with a heater in the container in order to maintain the dross in a molten state. Since solder contains tin, zinc, copper, etc. in addition to lead, a so-called metal that causes a chemical reaction between the stainless steel and the tin, zinc, copper, etc., that make up the outer casing of the heater, makes the heater thin. There is a problem that the biting phenomenon occurs. Therefore, since the heater deteriorates in a short period of time and the replacement frequency increases, the labor and cost of replacing the heater increase.
[0008]
In addition, when a heater is provided in the container, it is necessary to rotate the stirring piece for stirring the dross melt so that it does not come into contact with the heater. is there. Furthermore, since the container has a bottomed cylindrical shape, a portion that cannot be stirred easily occurs.
[0009]
Further, in order to prevent the thrown dross from hitting the heater disposed in the container, there is a waste of preliminarily storing the solder in the dross in a molten state in the container.
[0010]
Moreover, after visually confirming that the oxide residue was carbonized in the state where the solder was separated from the dross, the stirring was stopped, the lid of the container was opened, and the oxide residue floating on the molten solder was taken out, It is inefficient because it is necessary to pump out the regenerated solder, and continuous separation work is not possible. At the same time, there is a problem of pumping out the solder together with the oxide residue, and when pumping out molten solder. There is a problem with danger.
[0011]
The present invention was devised in view of the above-mentioned problems of the prior art, and only dross can be put into the melting tank and melted and stirred, and the apparatus is stopped from the operation of taking out only the solder separated from the dross from the melting tank. An object of the present invention is to provide a solder reproducing apparatus that can be carried out continuously without any problems.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, a solder recycling apparatus according to the present invention has a vertical axis connected to a rotation driving means in a melting tank having an inclined surface inclined toward a solder discharge port provided at the lowest position. A rotating stirring blade is disposed, a heater is disposed on the outer surface of the melting tank, a discharge port opening / closing means for opening and closing the solder discharge port is provided , and a solder recovery container is disposed immediately below the solder discharge port. A container mounting base with a heater is provided, and the discharge port opening / closing means includes a valve body fitted into the solder discharge port, a biasing means for biasing the valve body toward the inner side of the melting tank, and a biasing body for the valve body. Discharging operation means for pulling out of the melting tank from the solder discharge port against the urging of the means is provided .
[0013]
According to the solder recycling apparatus configured as described above, since the melting tank is heated by the heater disposed on the outer surface thereof, there is no obstacle to stirring inside, and stirring is performed uniformly by the stirring blade, and separated from the dross by stirring. Solder is led to the inclined surface and can be discharged from the solder discharge port provided at the lowest position of the melting tank, and oxide residue can be easily taken out above the melting tank, so that the work is hardly interrupted. It is possible to effectively perform continuous reproduction processing.
[0014]
[0015]
Further, since the provided heating with a heater vessel mounting rack to place the solder collection container immediately below the solder outlet, it is possible to accommodate the solder discharged from the solder outlet to the solder collection container, solder from the melting bath Solder discharged into the recovery container can be stored in a molten state. Therefore, even if the solder is discharged to the solder collection container at intervals, the previous and next solders are integrated because the previously discharged solder is in a molten state. If the solidified solder is taken out from the solder collecting container storing the solder, the regenerated solder having a fixed shape can be obtained in an ingot shape, which is effective for stacking and calculating the amount to be collected.
[0016]
[0017]
[0018]
The discharge port opening / closing means includes a valve body fitted into the solder discharge port, a biasing means for biasing the valve body toward the inner side of the melting tank, and the valve body against the bias of the biasing means. Since it is configured to include a discharge operation means that pulls out of the melting tank from the discharge port, the solder can be easily taken out from the melting tank only when the discharge operation means is operated.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.
[0020]
FIG. 1 and FIG. 2 show the configuration of the solder recycling apparatus 1 according to the embodiment, and a melting stirrer A for melting and stirring the dross d and the solder s separated from the dross d by stirring are recovered. And a rotational drive unit C that is a drive source for stirring the dross d.
[0021]
The melting stirrer A is formed around a melting tank 2 formed in a hemispherical shape with cast iron and having a flange 2a formed around the opening. The melting tank 2 includes a heat insulating material (not shown) on the flange 2a. It is installed on the housing 11 having a heat resistant structure. A heater 4 is disposed on the outer surface of the melting tank 2 to heat the melting tank 2 to a predetermined temperature (350 to 400 ° C.). In addition, a plurality of (three in this case) stirring blades 3 are provided in the melting tank 2 in a fan shape so that the tip ends along the inner surface of the melting tank 2, and each stirring blade 3 has a drive shaft 5. It is connected to. The stirring blade 3 is shaped and arranged so as not to stir the solder discharge port 6 formed in the bottom of the molten layer 2 and the vicinity thereof. Further, the opening of the melting tank 2 is closed with the lid 7 being detachable. The lid body 7 is provided with a dross insertion portion 7a for opening a part thereof and introducing the dross d into the melting tank 2, and a bearing 8 for supporting the drive shaft 5 through the outside is provided at the center portion. It has been.
[0022]
The solder recovery part B is provided with a conical valve body 13 that is fitted to the solder discharge port 6 that opens at the bottom of the melting tank 2 so as to be movable back and forth, a handle 15a at one end, and the other end at the housing 11 An opening / closing operation arm (discharge operation means) 15 that is pivotally supported by a provided support portion 14 and has the valve body 13 fixed at a substantially central portion thereof, and the valve body 13 is advanced into the solder discharge port 6. A coil spring (biasing means) 16 for urging the opening / closing operation arm 15 in a direction to close the solder discharge port 6, and pressing the opening / closing operation arm 15 downward to retract the valve body 13 from the solder discharge port 6. When the discharge port 6 is opened, a solder recovery container 17 that stores the molten solder s discharged from the solder discharge port 6 is provided.
[0023]
The rotation drive unit C includes a motor 21 having a reduction gear mounted on the outer surface of the housing 11, a first bevel gear 23 fixed to one end of a rotation transmission shaft 22 connected to the rotation shaft of the motor 21, A fourth bevel gear 26 fixed to the drive shaft 5 protruding outside from the lid body 7 and second and third fixed to both ends of a rotary connecting shaft 27 supported on the lid body 7 by a bearing 28. Each bevel gear 24, 25 is provided. The first bevel gear 23 and the second bevel gear 24 are meshed by disposing the lid 7 on the melting tank 2, and the first to fourth bevel gears 23, 24, 25, 26 are engaged with each other. It is connected to the motor 21 through the rotation transmission shaft 22 and the rotation connecting shaft 27, the rotation of the motor 21 is transmitted to the drive shaft 5, and the drive shaft 5 is rotated to rotate the stirring blade 3.
[0024]
The casing 11 on which the solder recycling apparatus 1 having the above configuration is mounted includes a caster 32 so as to be movable to an arbitrary place, and the solder recovery container 17 is directly below the solder discharge port 6 formed in the melting tank 2. A container arrangement shelf (container installation table) 12 is provided so that the solder recovery container 17 is disposed at a position where the solder recovery container 17 is disposed, and the solder s recovered in the solder recovery container 17 is melted. And can be stored. In addition, when a predetermined amount of solder is stored in the solder collection container 17 on the container arrangement shelf 12, a replacement solder collection container 17 to be arranged on the container arrangement shelf 12 is prepared in the case 11. I can do it.
[0025]
In the above configuration, as shown in FIG. 2, the dross introduction part 7 a is opened, the dross d is introduced into the melting tank 2, and the driving shaft 5 is rotationally driven by the motor 21 while the melting tank 2 is heated by the heater 4. When the stirring blade 3 is rotated, the melted dross d can be stirred while crushing the dross d. As described above, the dross d is a dross d obtained by scrubbing the oxide obtained by scrubbing the oxide which is oxidized when the solder s melted in the solder tank at the soldering site touches air. Contains a large amount of solder. The dross d introduced into the melting tank 2 may be in the form of a sherbet or after solidification, and is stirred in the molten state by the melting tank 2 heated by the heater 4. The solder s is separated from the dross d by stirring in the molten state, and the solder s sinks to the bottom side of the melting tank 2 due to the difference in specific gravity. Therefore, it is visually observed that the separation of the solder s has progressed, or for a predetermined time. When the separation is estimated from the progress and the handle 15a of the opening / closing operation arm 15 is pushed downward, the valve body 13 that has closed the solder discharge port 6 is retracted and the solder discharge port 6 is opened, and the bottom of the melting tank 2 is opened. The sinked solder s flows down from the solder discharge port 6 and is discharged into the solder collection container 17.
[0026]
The solder s discharged into the solder recovery container 17 is stored in a molten state while the solder recovery container 17 is heated by the container heater 18. The solder recovery container 17 discharges the solder s from the solder discharge port 6 by the pushing operation of the opening / closing operation arm 15 every time it is confirmed that the solder s is separated from the dross d in the melting tank 2. Since the amount of storage increases in the molten state, the solder s is solidified each time it is discharged and does not accumulate in an indeterminate shape or form a cavity inside, so that a predetermined amount of solder is stored. When the recovery container 17 is taken out and replaced with an empty solder recovery container 17, when the solder s stored in the solder recovery container 17 is solidified, it can be recovered as ingot-shaped solder s. The solder s solidified into a certain shape can be easily stacked, and the amount collected can be calculated accurately and easily.
[0027]
Since the melting tank 2 is formed of cast iron, it causes a chemical reaction with a metal such as tin contained in the dross d, so that the metal erosion phenomenon is less likely to occur, compared with the case where it is formed of stainless steel. A durability of twice or more can be obtained. In addition, since the heater 4 is not disposed in the melting tank 2, the stainless steel forming the outer cylinder of the heater 4 causes a chemical reaction with a metal such as tin contained in the dross d, and a metal erosion phenomenon occurs. The heater 4 is not deteriorated, and the life of the heater 4 can be extended to reduce the labor and cost for replacing the heater.
[0028]
Further, when there is no heater 4 in the melting tank 2, there is no need for preparatory work for storing the solder s previously melted in the melting tank 2 as in the prior art, and only dross d is put into the melting tank 2. Then you can start working. Further, since there is no heater 4 in the melting tank 2, the stirring blade 3 can be formed in a shape that rotates along the inner surface of the melting vessel 2, and the stirring efficiency is good and the solder s is efficiently separated from the dross d. be able to.
[0029]
Further, since the melting tank 2 is formed in a hemispherical shape, the solder s separated from the dross d is likely to gather at the bottom, and only the solder s can be discharged and recovered from the solder discharge port 6 provided at the bottom. . The stirring blade 3 disposed in the melting tank 2 is oxidized again to the solder s separated from the dross d and gathered at the bottom of the melting tank 2 by making the solder discharge port 6 and the vicinity thereof not stirred. Since no waste residue is mixed, high-purity solder s can be recovered.
[0030]
When the solder s separated from the dross d in the melting tank 2 is completely discharged from the solder discharge port 6, only the oxide residue remains in the melting tank 2, so that the operation of the solder recycling apparatus 1 is stopped. When the lid 7 is opened, the stirring blade 3 is also taken out, so that the oxide residue left in the molten layer 2 can be easily taken out and discarded without using a special tool. Further, after the oxide residue is taken out, the operation of cleaning the inside of the melting tank 2 can be performed reliably and easily from the shape of the melting tank 2. Therefore, even when dross d generated from solder having a different composition is processed, the remaining components of the dross d processed earlier are mixed into the dross d processed later, and the composition of the recovered solder s changes. There is nothing.
[0031]
When the lid 7 is removed from the melting tank 2, the second bevel gear 24 attached to the lid 7 is disengaged from the first bevel gear 23, and the lid 7 is placed on the melting tank 2 when the lid 7 is placed on the melting tank 2. The two bevel gears 24 have a simple structure that meshes with the first bevel gear 23 and are easy to maintain. Further, when the handle is fitted to the shaft protruding portion of the fourth bevel gear 26, the stirring blade 3 can be manually rotated.
[0032]
In the configuration described above, the shape of the melting tank 2 is hemispherical. However, the shape is not limited to this, and the shape in which the inclination angle gradually decreases toward the solder discharge port 6 provided at the bottom, and the like. If the inclined surface is provided, the same effect can be obtained.
[0033]
【The invention's effect】
As described above, according to the solder recycling apparatus according to the present invention, the melting tank is heated by the heater disposed on the outer surface thereof, so that there is no obstacle other than the stirring blades inside, and the dross that has become solid matter is removed. It can be put into a melting tank and stirred for melting. The molten dross can be evenly stirred by the stirring blades, and the dross is efficiently separated into solder and oxide residue by stirring, and the solder with a large specific gravity sinks to the bottom of the melting tank. When the solder discharge port is opened by the discharge port opening / closing means, the solder is discharged from the solder discharge port into a solder recovery container placed on the container mounting table, and only the solder can be easily recovered.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of a solder reproducing apparatus according to an embodiment.
FIG. 2 is a cross-sectional view showing a state when dross is inserted in the apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Solder reproduction apparatus 2 Melting tank 3 Stirring blade 4 Heater 5 Drive shaft 6 Solder discharge port 7 Cover body 12 Container arrangement shelf (container installation stand)
13 Valve body 15 Open / close operation arm (discharge operation means)
16 Spring (biasing means)
17 Solder collection container 21 Motor

Claims (4)

In the melting tank having an inclined surface inclined toward the solder discharge port provided at the lowermost position, a stirring blade rotating around a vertical axis connected to the rotation driving means is disposed, and on the outer surface of the melting tank. A heater is provided, and a discharge port opening / closing means for opening and closing the solder discharge port is provided , and a container installation table with a heater for arranging a solder recovery container is provided directly below the solder discharge port. A valve body fitted into the solder discharge port, a biasing means for biasing the valve body toward the inner side of the melting tank, and the valve body against the biasing of the biasing means from the solder discharge port to the outside of the melting tank. A solder reclaiming device comprising a discharge operation means for pulling out .   The solder recycling apparatus according to claim 1, wherein the melting tank is formed in a hemispherical shape. 3. The solder recycling apparatus according to claim 1, wherein the stirring blade has a shape that rotates along the inner surface of the melting tank excluding the solder discharge port and the vicinity thereof. Melting tank, solder reproducing apparatus according to any one of claims 1 to 3 the material is cast iron.

Images