JP2604773B2 - Electrode processing equipment for chip components - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode processing apparatus for a chip component such as a chip resistor, which is a kind of electronic component that contributes to weight reduction, thinning, and miniaturization of electronic equipment. is there.

2. Description of the Related Art Conventionally, this type of chip component has a configuration as shown in FIG. FIG. 2 shows a cross-sectional view of a square chip resistor as an example, wherein 1 is an insulating substrate such as alumina, 2 is a resistor, 3 is a silver-based electrode film, 4 is a nickel (Ni) film, 5 is A solder (Sn-Pb-based alloy) [or tin (Sn) or lead (Pb)] film deposited by an electroplating method, and 6 is a glass coating film for protecting the low antibody 2.

As described above, the conventional chip component has a low-melting-point metal plating film or a low-melting-point alloy plating film (hereinafter, these are collectively referred to as a low-melting-point metal plating film) on the outermost layer of the electrode portion, and a base layer (here, As the nickel film 5), a high melting point metal film or a high melting point alloy film (hereinafter, referred to as a high melting point metal film) made of a material having a higher melting point than the low melting point metal plating film and having a good affinity for the low melting point metal plating film. (Collectively referred to as).

In such a conventional chip component, the outermost layer of the electrode portion is formed of a low-melting metal plating film, the surface is rough, and the surface area is very large. As a result, these films tend to occlude foreign substances and adsorb gases, and when stored for a long period of time, cause chemical changes such as oxidation on the electrode surface, resulting in poor soldering when soldering to printed circuit boards. There is a problem that there is a high possibility of causing such a situation. In addition, when the low-melting metal plating film is made of bright plating to make the surface smooth, there is a fatal defect that solderability is poor because it contains impurities (organic substances). I have.

An atmosphere furnace, an infrared furnace, a hot blast furnace, a hot plate, or the like is used as an electrode processing apparatus for smoothing the low melting point metal plating film having a rough surface of the electrode portion as described above. A heating electrode processing apparatus or an apparatus using a vapor phase soldering method (VPS method) is known. Among them, an electrode processing apparatus for a chip component using an infrared heater will be described below as an example.

FIG. 3 is a schematic configuration diagram of an electrode processing apparatus using the infrared heater.

In FIG. 3, 7 is a chip component having the structure shown in FIG. 2, 8 is a chip component aligner, 9 is a flux coater, 10 is an infrared heater, 11 is a cooler, and 12 is an electrode processed. A chip component take-out machine, 13 is a belt drive unit, 14 is an electrode processing apparatus mount, 15 is a chip component transport belt, and 16 is a belt washer.

The process of melting the low-melting metal plating film of the electrode part of the chip component includes five steps of chip component alignment, flux application, heat melting, cooling and solidification, and chip component removal. That is, the belt driving unit 13
The chip components 7 are supplied from the chip component aligning machine 8 onto the chip component transport belt 15 conveyed by the above-mentioned method, and the flux is applied to the chip components 7 in the next step, and then the flux is applied by the tunnel type infrared heater 10. That is, the electrode part is heated and melted, and then the melted part is cooled and solidified by the cooling part 11, and thereafter, the chip part 7 having been subjected to the electrode processing is taken out by the chip part picking up machine 12 with the electrode processing. Also,
After the chip component transport belt 15 is cleaned by the belt cleaning device 16, the chip component 7 is supplied thereon again.

In such a conventional electrode processing apparatus, independent equipment is required for each process, and the chip component conveying belt is contaminated with flux. Therefore, a cleaning device must be provided. In addition, the equipment must be large due to such a situation, and furthermore, in order to take the timing between the equipments (the transfer speed of the chip components conveyed by the conveyor belt, the timing of the flux application and the chip component removal) must be adjusted. In order to synchronize), there is a fundamental problem that the equipment must be accurate.

Hereinafter, problems of the above-described electrode processing apparatus will be enumerated.

When the electrode parts of chip components are melted, the individual chip parts must be spaced and aligned so that the electrode parts of the chip parts do not stick together, which is a major factor that hinders mass productivity .

Since it is heated and melted in the air, a flux is required to prevent oxidation of the surface of the molten metal.

Since the flux is used, the flux is heated and seized on the chip component, and it is difficult to clean the chip component.

Since the heating section is of a tunnel type, air flows freely in and out, and it is difficult to stabilize the temperature.

Since the conveyor belt is also heated at the same time, it takes a long time for heating and cooling, so that a very long furnace is required, and a cooler is required for rapid cooling.

Since the flux adheres to the conveyor belt and causes a failure of the equipment, the conveyor belt must be cleaned.

Even when viewed from the whole equipment, there are many mechanically moving parts, and the flux is used thereon, so that the flux adheres to the moving parts of the equipment and causes a failure, which is likely to cause a reduction in the operation rate of the equipment.

As described above, the electrode processing apparatus using the infrared heater shown in FIG. 3 has many problems, and its improvement is strongly demanded.

Further, the other electrode processing apparatuses described above also have problems similar to those of the electrode processing apparatus using the infrared heater, which are larger or smaller. The dimensions of chip components are generally as small as 3.2 mm x 1.6 mm, and recently, very small chip components such as 2.0 mm x 1.25 mm have been used, and the size of such components has become increasingly smaller. The tendency is getting stronger. As described above, the dimensions of chip components may be very small, and as described above, the conventionally known electrode processing apparatus may have a number of problems. The fact is that almost no process for smoothing the surface of the electrode portion is performed on the component.

The present inventors have previously proposed an electrode processing device for a chip component having a new configuration as a device that has eliminated the disadvantages of such an electrode processing device. The electrode processing apparatus for chip components having the structure shown in Japanese Patent Application No. 61-174219, which is the basis of these proposals and which is most easily realized, is shown in FIG. This will be described below.

This device fills a high-boiling liquid 18 such as oil into the inside thereof, and feeds a chip component 7 having a film or a layer made of a low-melting-point metal or a low-melting-point alloy on the outermost layer of the electrode at one end. , A heater 19 disposed at one end of the cylindrical container so as to impart a temperature gradient to the high-boiling liquid, and a heater 19 disposed at the other end of the cylindrical container. And a plurality of cocks 21 and 22. The cocks 21 and 22 are provided below the cylindrical container 17 and a take-out part 23 for removing the processed chip part 26 is provided on the cock part side. Things.

Next, a method of treating the surface of the electrode portion of the chip component 7 using the apparatus shown in FIG. 4 will be described. First, at the stage of performing the electrode treatment, the upper cock 21 is opened and the lower cock 22 is closed as shown in FIG. In this state, the upper part of the glass cylindrical container 17 is
Heat to 0-280 ° C. At this time, since the coconut oil as the high boiling point liquid 18 is contained in the cylindrical container 17, the high boiling point liquid 18 is heated to 250 to 280 ° C. The heated high-boiling liquid 18 has a low specific gravity, and does not convect to a low-temperature portion having a large specific gravity at a lower portion, but generates a convection only at an upper portion on a charging portion side.
Therefore, the high-boiling liquid 18 in the cylindrical container 17 has a temperature gradient from a high temperature state to a low temperature state from the upper part to the lower part, and the bottom part can be kept at room temperature. Then, to a place where the preparation is completed as described above, a chip component having a low melting point metal plating film in the outermost layer of the electrode portion from the parts feeder 20 in the cylindrical container 17 from the charging portion above the liquid level of the high boiling point liquid 18 7 is input. By this introduction, the chip component 7 falls in the high boiling point liquid 18. At this time, the low-melting metal plating film provided on the outermost layer of the electrode portion is melted in the high-temperature portion heated to 250 to 280 ° C., and falls to the low-temperature portion having a temperature gradient, and the low-temperature portion is heated. The melted part is solidified on the side and accumulates on the cock 22 on the bottom side in the cylindrical container 17 as a processed chip component 26 having electrodes having a smooth surface. At this time, since the bottom side of the cylindrical container 17 is at room temperature, there is no fear that the processed chip components 26 will stick together. As for the removal of the chip component 26 after the electrode surface treatment, the cock 21 is opened and the cock 22 is closed during the electrode processing as described above. Now, when the processing is completed, the cock 21 is closed, and when the cock 22 is opened while the bottom opening 24 of the cylindrical container 17 is held below the liquid level in the high boiling point liquid reservoir 23, the electrode-treated chip is finished.
26 falls on the mesh receiver 25 by its own weight. Next, after confirming that the dropping has been completed, place the mesh
Withdrawing from the high-boiling liquid 18 in 23 ends the removal.

Thereafter, the removed processed chip component 26 is washed to be a finished product.

According to the electrode processing apparatus proposed earlier by the present inventors, a film or layer made of a low-melting-point metal (low-melting-point alloy) is melted on the high-temperature side of the high-boiling liquid in the container and cooled on the low-temperature side. As a result, the surface tension acts during melting, and the surface area is reduced. By cooling in this state, compared with a low melting point metal film (low melting point alloy film) formed by a plating film or the like, The surface area becomes extremely small, and the surface becomes smooth, so that a chip component with extremely little adhesion of foreign substances and adsorption of gas during storage can be obtained. In addition, foreign substances and gases adsorbed and occluded on the surface or inside the cavity during melting are also released, so the outermost layer itself becomes a clean film containing no impurities, and has good solder wettability and soldering reliability. Thus, a chip component that leads to improvement in the quality can be obtained. Then, the electrode processing can be performed simply by moving the chip component in the high boiling point liquid from the high temperature part side to the low temperature part side without using complicated equipment. In addition, the melting and cooling are performed in the high boiling point liquid, and the electrodes of the chip parts do not stick together in the low temperature part.
The chip components can be processed simply by putting them in large quantities in a discrete state without being aligned at the time of electrode processing. In addition, since the chip components are in contact with the liquid, heating and cooling can be completed in a short period of time. The mass productivity is high. Further, since melting and cooling are performed in a high boiling point liquid and there is no opportunity to come into contact with air, there is no fear that the surface of the electrode portion is oxidized even during melting. In addition, performing a melting treatment in a liquid means that a high-boiling liquid in contact with a molten material (such as a low-boiling metal or a low-melting alloy) has a higher specific gravity and a higher viscosity than air. For this reason, pressure is applied to the molten metal from the surroundings, so that the surface of the molten metal has a smooth surface without waving and has a uniform thickness. In addition, the use of an oil such as natural vegetable oil or a liquid having a flux action such as glycerin as a high boiling point liquid eliminates the need for a flux, which simplifies the equipment and cleans the processed chip components. It will be very easy.

As described above, the electrode processing apparatus proposed by the present inventors largely solves the drawbacks of the conventional apparatus, but has the following problems in terms of automation, productivity, and safety. It has.

In order to construct this cock type device, it is easy to manufacture it with glass.However, if it is made of glass, there is a danger that the high boiling liquid flows out of the container due to breakage of the container, It has a big problem in terms of safety.

In order to process a large number of electrodes without causing chipping between the electrodes of the chip component being processed, it is effective to increase the opening diameter of the chip component, but for the above reasons, manufacture the container with glass In such a case, there is a limit on the diameter of the input port, and there is a limit on the expansion of large-scale high-speed processing of equipment.

In order to solve the above-mentioned problems and the above-mentioned problems, it is preferable that the present apparatus is constituted by a metal pipe or the like. In this case, leakage of a high boiling point liquid, biting of a small chip component, remaining, and the like do not occur at all. A special valve (shutter) must be constructed, and special measures are required.

In the case of using a metal pipe as described above, since the thermal conductivity of metal is higher than that of glass, a special contrivance or a considerably large size compared to glass is required to give a high-boiling liquid a predetermined temperature gradient. Device is required.

In order to automate this system, it is necessary to replace the glass container with a metal container, but this requires considerable contrivance as described above.
Automation with this method is difficult.

Problem to be Solved by the Invention The present invention solves the above-mentioned problems of the electrode part of the chip component, reduces the surface area of the electrode part of the chip component, and furthermore, improves the solder wettability and long-term storage. It is a first object of the present invention to provide an electrode processing apparatus capable of improving the reliability of soldering. Also,
A second object of the present invention is to solve the problems of the conventionally known electrode processing apparatus, to eliminate the moving parts of the machine fluid, and to dispose the chip parts without aligning them, even if the chip parts are arranged without being aligned. Without the electrode parts of the chip parts sticking together,
It is an object of the present invention to perform a melting process, accurately control a melting temperature, and perform an electrode treatment of a chip component with good mass productivity without using a flux. Further, a third object of the present invention is to eliminate the drawbacks of the electrode processing apparatus proposed by the present inventors, that is, the problems related to safety, further improve the productivity, and facilitate automation. An object of the present invention is to provide an electrode processing apparatus.

Means for Solving the Problems In order to solve the above problems, the present invention has a high melting point metal film or a high boiling point alloy film as a base layer at both ends of an insulating base and a low melting point metal as an outermost layer. In an electrode processing apparatus for a chip component having an electrode portion having a film or a low-melting point alloy film, a tank filled with a high-boiling liquid having a function of a flux such as oil therein, and the high-boiling liquid immersed in the tank and contained therein And a charging section for charging the chip component into the cylindrical container, wherein the cylindrical container has a double wall at an upper portion and a single wall at a lower portion, and a single wall and a double wall. A state in which a liquid escape gap is provided at the boundary of the inner wall and a heater is provided on the upper outer peripheral portion of the inner wall between the inner wall and the outer wall of the double wall, and the lower end of the cylindrical container is floated from the bottom surface of the tank. It is arranged in.

According to this configuration, a film or layer made of a low-melting-point metal (low-melting-point alloy) is melted on the high-temperature side of the high-boiling liquid in the container and cooled on the low-temperature side, so that surface tension acts during melting. The surface area is small. By cooling in this state, the surface area is extremely small compared to that of a low melting point metal film (low melting point alloy film) formed by a plating film and the surface is smooth. As a result, it is possible to obtain a chip component having extremely little adhesion of foreign substances and adsorption of gas during storage. In addition, foreign substances and gases adsorbed and occluded on the surface or inside the cavity during melting are also released, so the outermost layer itself becomes a clean film containing no impurities, and has good solder wettability and soldering reliability. Thus, a chip component that leads to improvement in the quality can be obtained. Then, the electrode processing can be performed simply by moving the chip component in the high boiling point liquid from the high temperature part side to the low temperature part side without using complicated equipment. In addition, since the melting and cooling are performed in the high boiling point liquid and the electrodes of the chip parts do not stick together in the low temperature part side, the chip parts are not aligned at the time of the electrode processing, and a large amount of the chip parts is disintegrated. The heating and cooling are completed in a short time because the chip component is in contact with the liquid, so that the productivity is extremely high. Further, since melting and cooling are performed in a high boiling point liquid and there is no opportunity to come into contact with air, there is no fear that the surface of the electrode portion is oxidized even during melting. Also,
Performing a melting process in a liquid means that the high-boiling liquid in contact with the melt (such as a low-melting metal or low-melting alloy) has a higher specific gravity and a higher viscosity than air. , Will apply pressure to the molten metal from the surroundings,
The molten metal has a smooth surface without waving and a uniform thickness. In addition, by using a liquid having a flux action such as oil such as natural vegetable oil or glycerin as a high boiling point liquid,
No flux is required, which simplifies the equipment and makes cleaning of the processed chip components very easy.

In addition, since this electrode processing device is a cockless type, when removing processed chip components, cock operation (valve operation)
Is unnecessary and can be easily automated. In addition, since it can be made of metal or the like that is stronger than glass, there is no restriction on the inlet aperture, and it is possible to process a large amount without generating cracks between the electrodes of the chip component being processed, and increase productivity Can also be planned. Furthermore, since it is a metal tank and there is no cock operation, there is little danger of a high-temperature high-boiling-point liquid flowing out, and safety is greatly improved.

In addition, since the present apparatus is configured by inserting the cylindrical container into the tank, the configuration, assembly, and maintenance of the apparatus for removing processed chip components are simple, and automation is also easy.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing an example of a chip component electrode processing apparatus according to the present invention.

In FIG. 1, reference numeral 7 denotes a chip component having a structure as shown in FIG. 2, which is denoted by the same reference numeral as in FIGS. 27 is, for example, a stainless steel box-shaped tank having a height of about 180 cm, a width of 50 cm, and a length of 130 cm, and 18 is a high-boiling liquid placed in this tank 27, here is a coconut oil of a natural vegetable oil. . Numeral 28 is a cylindrical container made of stainless steel. In this example, a liquid escape gap 29 is provided at an intermediate portion. Reference numeral 30 denotes a heater such as a mantle heater attached to the upper part of the cylindrical container 28. An air layer 32 is formed on the upper part of the cylindrical container 28 and on the outer peripheral part of the heater 30 by a stainless shielding plate 31, and is thermally isolated from the outside to maintain insulation. The cylindrical container 28, the heater 30 and the shielding plate 31 are inserted from above into a box-shaped tank 27 filled with the high-boiling liquid 18, and as shown in the figure, the cylindrical container 28 has a somewhat high-boiling liquid It is sunk to protrude above the liquid level of 18, and the lower surface is a tank
It is arranged to be slightly higher than the bottom of 27. The lower surface of the cylindrical container 28 may be in contact with the lower surface of the tank 27 so that the entire cylindrical container 28 can move up and down.

Here, reference numeral 33 denotes an upper portion in the cylindrical container 28, reference numeral 34 denotes a lower portion in the cylindrical container 28, and reference numeral 35 denotes a portion outside the shielding plate 31 and inside the tank 27. Reference numerals 36, 37, and 38 denote a feeder, a line feeder, and a rotary chute, respectively, into which the chip component 7 is charged from the liquid level of the cylindrical container 28.

Reference numeral 26 denotes an electrode-processed chip component, which accumulates in an extraction network 39 for the processed chip component.

Numeral 40 denotes a coagulation-preventing and warming device for the high-boiling liquid 18 attached to the bottom of the tank 27, and numeral 41 denotes a draining tray when the extraction net 39 is taken out of the tank 27.

Next, a method of treating the surface of the electrode portion of the chip component 7 using the apparatus shown in FIG. 1 will be described.

First, as a preparation, the high boiling liquid in the upper portion 33 in the cylinder is heated to (250 to 280 ° C.) by the heater 30. Heated cylindrical container
The high-boiling liquid 18 in the upper part 33 in the inner part 28 has a low specific gravity, and convection occurs only in the upper part without convection with the low-temperature high-boiling liquid 18 having a large specific gravity in the lower part.

For this reason, inside the cylindrical container 28, the temperature in the upper part 33 in the cylinder becomes high, and the temperature in the lower part 34 in the cylinder becomes room temperature, so that a temperature gradient is formed.

At this time, the high-boiling liquid 18 in the portion 35 is kept at normal temperature because it is thermally shielded from the heater 30 and the high-temperature in-cylinder upper portion 33 by the shielding plate 31.

At the place where the preparation is completed as described above, the chip component 7 is put into the upper portion 33 in the cylinder, which is at a high temperature, by the supply device 36, the line feeder 37, and the rotating chute 38.

Since the rotating chute 38 always bleeds air out of the chute, the inside of the chute does not get wet by the vapor of the high boiling point liquid 18 and the chip parts 7 are not caught in the chute.

Here, the chip component 7 used in the embodiment is a square plate type chip resistor, and the outermost layer of the electrode portion is formed of Ag-Pd, and the intermediate layer is formed of an intermediate layer.
Ni, Sn = Pb = 60: 40 for the outermost layer (low melting point metal plating film)
Having an electroplating film having a thickness of 7 to 10 μm.
The melting point of the outermost layer material is 180 to 190 ° C.

The chip components 7 supplied by the rotating chute 38 fall in a state of being separated individually, and the Sn-Pb alloy plating film, which is the outermost layer of the electrode, is melted at the upper portion 33 in the cylinder heated to 250 to 280 ° C. Falling into a low temperature area with a temperature gradient,
The melted part is solidified from the point when the temperature of the high boiling liquid 18 as coconut oil has passed about 180 ° C. or less, and the processed chip part 26 having electrodes with smooth surfaces is a processed chip part 26 of the cylindrical container 28. It falls to the bottom and accumulates in the extraction net 39. The take-out net 39 is pulled up from the room temperature liquid level 35 to take out the processed chip component 26.

When the cylindrical container 28 can be moved up and down with respect to the bottom surface of the tank 27, the cylindrical container 28 is lowered so as to be in contact with the bottom surface of the tank 27 at the time of electrode processing of the chip component. The chip components 26 are stored in the bottom of the cylindrical container 28, and when the chip components are taken out, the cylindrical container 28 is raised, and the processed chip components are taken out therefrom by using a takeout net 39 or the like.

Here, the processed chip components 26 are collected at the extraction net 39 at room temperature or the bottom of the cylindrical container 28, so that the processed chip components 26
26Even if they come in contact, the electrodes will not stick together,
Even at the time of removal, since it is performed from 35 normal temperature liquid level, it does not stick.

Thus, the melting process of the low melting point metal plating film of the chip component 7 is performed. Further, the removed processed chip component 26 is completed only by washing thereafter.

Here, in the above-described embodiment, the case where coconut oil is used as a high-boiling-point liquid with a natural vegetable oil has been described, but this is also applicable to natural animal oils, natural mineral oils, and synthetic silicone oils. , Or a material having a flux action such as glycerin can be used as a material having the same effect. Further, the melting point of the melt (low-melting metal film) in the electrode portion of the chip component is not limited to these materials. Any high-boiling liquid having a higher boiling point can be used.

The outermost layer of the electrode portion of the chip component to be melted in the apparatus of the present invention is not limited to a low melting point metal plating film (low melting point alloy plating film) formed by electroplating or chemical plating. The low melting point metal film (low melting point alloy film) formed by the above method may be used. In addition, as a material for forming these low melting point metal films (low melting point alloy films), in addition to the solder of the above-mentioned embodiment, commonly used tin and further lead can be used.

The melting point of the low melting point metal film (low melting point alloy film) is 100
550 ° C., and the film thickness is preferably 1 μm or more. First, if the melting point is lower than 100 ° C, the remelted metal film may be melted by self-heating during the use of components after soldering, and if it exceeds 550 ° C, the resistor and coating film will be destroyed. As a result, the performance as a chip component may not be maintained. If the film thickness is less than 1 μm, a uniform film cannot be formed after the heat treatment, so that the reliability of soldering at the time of mounting is reduced and the wafer is oxidized during storage. It has been confirmed by experiments that if the film thickness is 8 to 15 μm, soldering is very easy.

Furthermore, the electrode processing apparatus according to the present invention has a solderable metal film or alloy film such as iron or a magnetic alloy, and a low-melting metal paste or a low-melting alloy paste applied to the outermost layer and dried. The present invention is also applicable to chip components having the same. In this case, it is needless to say that the melting point of the solderable metal film (alloy film) as the underlayer is higher than the melting point of the high boiling point liquid. When the chip component having the outermost layer of the low-melting-point metal (low-melting-point alloy) paste applied and dried is subjected to electrode treatment by the apparatus of the present invention, the low-melting-point metal (low-melting-point alloy) paste layer is electrically Than what is composed of plating film and chemical plating film,
This is advantageous in making the thickness related to the soldering reliability thick and uniform. Also, low-melting point metal (low-melting point alloy) paste usually contains flux,
This flux dissolves in the high boiling point liquid during melting,
It does not burn and does not hinder the effect. In the chip component having this structure, the thickness of the layer made of the low-melting-point metal (low-melting-point alloy) paste is preferably 3 μm or more in a dry state, particularly 25 to 100 μm.
m thickness is suitable.

Effect of the Invention As described above, the electrode processing apparatus for a chip component according to the present invention is configured and has many features. First, a film or layer made of a low-melting-point metal (low-melting-point alloy) is melted on the high-temperature side of the high-boiling liquid in the container and cooled on the low-temperature side. When cooled in this state, the surface area becomes extremely smaller than that of a low-melting metal film (low-melting alloy film) formed of a plating film, etc., and the surface becomes smoother during storage. This makes it possible to obtain a chip component with extremely little adhesion of foreign matter and adsorption of gas. In addition, foreign substances and gases adsorbed and occluded on the surface or inside the cavity during melting are also released, so the outermost layer itself becomes a clean film containing no impurities, and has good solder wettability and soldering reliability. Thus, a chip component having improved characteristics can be obtained. Then, the electrode processing can be performed simply by moving the chip component in the high boiling point liquid from the high temperature part side to the low temperature part side without using complicated equipment. In addition, the melting and cooling are performed in the high boiling point liquid, and the electrodes of the chip parts do not stick together in the low temperature part.
The chip components can be processed simply by putting them in large quantities in a discrete state without being aligned at the time of electrode processing. In addition, since the chip components are in contact with the liquid, heating and cooling can be completed in a short period of time. The mass productivity is high. Further, since melting and cooling are performed in a high boiling point liquid and there is no opportunity to come into contact with air, there is no fear that the surface of the electrode portion is oxidized even during melting. In addition, performing the melting process in a liquid means that the specific gravity of the high-boiling liquid that is in contact with the molten material (such as a low-melting-point metal or a low-melting-point alloy) is higher and the viscosity is higher than that of air. For this reason, pressure is applied to the molten metal from the surroundings, so that the surface of the molten metal has a smooth surface without waving and has a uniform thickness. In addition, the use of an oil such as natural vegetable oil or a liquid having a flux action such as glycerin as a high boiling point liquid eliminates the need for a flux, which simplifies the equipment and cleans the processed chip components. It will be very easy.

 Further, the effects of the present invention are listed below.

Since chip components can be put in without being aligned, processing can be performed by the same equipment regardless of the dimensions of the chip components. Also, chip components having different dimensions can be mixed and processed.

Since the processing can be performed without using a flux, the chip components can be easily cleaned, and further, there is no seizure of the flux and the finished product is beautiful.

Since the heat medium is a high boiling point liquid, the temperature control is also highly accurate, and since the high boiling point liquid and the chip component are in contact, heat conduction is fast, melting and solidification can be performed in a short time, and the reliability of the melting process is high. High in nature. That is, there is no failure in melting.

Since the high-boiling-point liquid is provided with a temperature gradient, the processed chip components can be accumulated in the low-temperature portion in a pile at a time, and can be taken out at once, and the taking-out work can be greatly simplified.

Further, in the present invention, since the upper portion (heating portion) of the cylindrical container has a double wall structure and the lower portion (cooling portion) has a single wall structure, and a liquid escape gap is provided at the boundary between the double wall and the single wall, the chip Even if the high boiling liquid in the cylindrical container rises in temperature due to heat treatment of the parts,
Since the high boiling point liquid whose temperature has risen from the liquid escape gap escapes to the outside of the cylindrical container, a cooling device is not required, and the high boiling point liquid in the cylindrical container can be kept very easily at a stable temperature gradient at all times.

Further, by providing a single wall with a liquid escape gap, the high boiling point liquid which has been heated will escape from the liquid escape gap at the end of the double wall, so that the high boiling point liquid is taken out when removing parts or replenishing the high boiling point liquid. When the liquid is stirred, the high-boiling liquid in the double structure is not stirred with the high-boiling liquid outside the cylindrical container, and the temperature gradient in the double structure does not break down. In other words, even if the liquid outside the cylindrical container first becomes agitated with the high-boiling liquid in the single wall at the tip of the cylindrical container, the high-boiling liquid whose temperature has risen from the liquid escape gap ends at the double-walled end. As a result, the liquid in the single wall does not enter the double wall and the temperature gradient in the double wall does not collapse.

By selecting the type or specific gravity of the high boiling point liquid, the passage time of the chip component in the liquid can be changed. Also, by changing the temperature gradient of the high boiling point liquid, the specific gravity changes, so that the passage time of the chip component in the liquid can be similarly changed. This makes it possible to easily cope with a change in the type or size and shape of the film or layer made of the low melting point metal or low melting point alloy of the chip component.

Since there is no cock, there is no quality abnormality at all due to the chip parts being caught or bitten.

Since there is no cock, there is no outflow of high-boiling high-temperature liquid due to poor cock operation and lack of tightness of the cock.

The metal tank structure can be used, the strength against impact, stress, etc. is high, the risk of high-temperature high-boiling liquid flowing out due to breakage of the container is small, and the safety is excellent.

Since it can be made of metal, there is no limit on the size of the input port for chip components, and it is possible to perform high-speed mass processing without causing sticking of electrodes of chip components being processed. Can be expanded.

Since there is no cock, it is easy to automate the removal operation, and it is easy to connect and line with the cleaning operation of the electrode-treated chip component.

Since this device is configured by inserting a cylinder into the tank, the configuration of the device for removing processed chip parts,
Easy assembly and maintenance.

The configuration of this device is simple and can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of an electrode processing apparatus for chip components according to the present invention, FIG. 2 is a cross-sectional view showing a square chip type resistor which is a kind of chip components, and FIG. FIG. 4 is a schematic configuration diagram showing an example of a device for performing electrode processing of a chip component, and FIG. 4 is a schematic configuration diagram of a chip component electrode processing device proposed by the present inventors previously. 7: Chip components, 18: High boiling point liquid, 26: Treated chip components, 27: Tank, 28: Cylindrical container, 30: Heater, 31: Shield plate, 32: Air layer , 33 …… upper part in the cylinder,
34: Lower part in the cylinder, 36: Feeder, 37: Line feeder, 38: Rotating chute, 39: Extraction net.

 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Osamu Toyooka 1006 Kazuma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. 19073 (JP, B2)

Claims (3)

(57) [Claims] 1. An electrode treatment of a chip component having an electrode portion having a high melting point metal film or a high boiling point alloy film as a base layer and an electrode portion having a low melting point metal film or a low melting point alloy film as an outermost layer at both ends of an insulating base. In the apparatus, a tank filled with a high-boiling liquid having an action of a flux such as oil inside, a cylindrical container immersed in the tank and filled with the high-boiling liquid inside, and the chip component as the cylindrical container The cylindrical container has a double wall at the top and a single wall at the bottom, providing a liquid escape gap at the boundary between the single wall and the double wall, and the inner wall of the double wall. An electrode processing apparatus for a chip component, wherein a heater is arranged on an outer peripheral portion of an upper portion of an inner wall between outer walls, and a lower end of the heater is arranged in the cylindrical container so as to float from a bottom surface of the tank. 2. Electrode treatment of a chip component having a high melting point metal film or a high boiling point alloy film as a base layer and an electrode portion having a low melting point metal film or a low melting point alloy film as an outermost layer at both ends of an insulating base. In the apparatus, a tank filled with a high-boiling liquid having an action of a flux such as oil inside, a cylindrical container immersed in the tank and filled with the high-boiling liquid inside, and the chip component as the cylindrical container The cylindrical container has a double wall at the top and a single wall at the bottom, providing a liquid escape gap at the boundary between the single wall and the double wall, and the inner wall of the double wall. An electrode processing apparatus for a chip component, wherein a heater is arranged on an outer peripheral portion of an upper portion of an inner wall between outer walls, and the cylindrical container is arranged so as to be vertically movable with respect to a bottom surface of the tank. . 3. The method according to claim 1, wherein the high-boiling liquid is any one of a natural vegetable oil, a natural animal oil, a natural mineral oil, a synthetic silicone oil, and glycerin. Electrode processing equipment for chip parts.