JP3367266B2 - Solder coating method for electrode of coil parts - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for solder coating an electrode of a coil component.

[0002]

2. Description of the Related Art Conventionally, as a method of coating the electrode surface of a coil component with solder, a method of immersing the electrode in a molten solder bath has been generally used. Low manufacturing cost,
Moreover, it is a method suitable for mass production. In addition to this, a method is also known in which cream solder is applied to the electrode surface and then dried to coat the electrode surface of the coil component with the solder.

[0003]

However, the solder coating by the dipping method or the solder cream method has a problem that a large amount of solder adheres to the electrode surface. When the amount of solder to the electrode exceeds an appropriate amount, as shown in FIG. 4, the surface tension of the solder causes the solder 53 to bulge up on the electrode 52, and the external dimension accuracy of the coil component 51 deteriorates.

Also, when the component 51 is mounted on a printed circuit board or the like, the component 51 is inclined due to the bump-like solder 53,
There is a possibility that the component 51 may not be temporarily attached to a printed circuit board or the like, or a tombstone phenomenon may occur in which the component 51 rises up. Therefore, it is an object of the present invention to provide a method capable of forming a solder coating film having a thin film thickness without solder bumps on the electrodes of a coil component.

[0005]

In order to achieve the above object, a method of coating a solder on an electrode of a coil component according to the present invention is performed by melting a hump-shaped solder formed on an electrode surface of the coil component, It is characterized in that, while vibrating a suction nozzle close to or in contact with the electrode surface in a direction substantially parallel to the electrode surface, the suction nozzle sucks excess solder from the molten solder.

Further, in the method for coating the electrode of the coil component with solder according to the present invention, (a) the bump-like solder formed on the electrode surface of the coil component is brought into contact with the nozzle plate of the excess solder sucking device, and the excess solder is removed. A step of melting the hump-shaped solder that has come into contact with the nozzle plate by a heating means provided in the suction device; and (b) bringing the suction nozzle provided in the nozzle plate close to or in contact with the electrode surface, A step of sucking excess solder from the molten solder by the suction nozzle while vibrating in a direction substantially parallel to
It is characterized by having.

[0007]

By the above method, the hump-shaped solder formed on the electrode surface is melted to make it easy to absorb it, and the excess solder is absorbed by the suction nozzle, so a thin solder coating film is formed on the electrode surface. To be done. Further, when sucking the excess solder with the suction nozzle, the suction nozzle is vibrated in a direction substantially parallel to the electrode surface, so that the excess solder is completely sucked and no solder icicles or end surface electrode solder bumps are generated.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for solder coating an electrode of a coil component according to the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, the excess solder sucking device is roughly composed of a solder sucking block 2 and a carrying block 3.
It is composed of. The solder suction block 2 includes a nozzle plate 21, an intermediate heat transfer plate 22, and a hot plate 23. The nozzle plate 21 is provided with suction nozzles 24 at a pitch that matches the electrode pitch of the coil component. These suction nozzles 24 are connected to a manifold 25 provided on the intermediate heat transfer plate. Heater 2 on hot plate 23
6 has a built-in hole 2 connected to the manifold 25
7 is also provided. The hole 27 is connected to a vacuum pump (not shown) via a joint pipe 28. Further, the solder sucking block 2 is provided with a mechanism that vibrates in its entirety in at least one of the front-rear direction and the left-right direction.

The transfer block 3 comprises a base plate 31, a shaft 32, a coil spring 33, and a work support plate 34.
Shafts 32 are attached to the left and right sides of the base plate 31, respectively. This shaft 32 is a coil spring 33.
And is elastically movable in the axial direction by the spring force of the spring 33. A work support plate 34 is vertically joined to the shaft 32 at the lower end of the shaft 32. Further, the transport block 3 is provided with a mechanism that moves in the vertical direction as a whole.

A method of solder-coating the electrodes of the coil component will be described using the surplus solder absorbing device having the above structure. As shown in FIG. 1, the coil component 1 in which the bump-like solder 11 is formed on the electrode surface by the dipping method or the solder cream method is temporarily attached to the transfer pallet 12 with the solder 11 facing down by a double-sided tape or the like. Next, the transfer pallet 12 to which the component 1 is temporarily attached is fixed to the work support plate 34.

Next, the carrier block 3 is lowered in the direction of the arrow a, and as shown in FIG.
Touch the upper surface of. The nozzle plate 21 is heated by the heater 26 via the hot plate 23 and the intermediate heat transfer plate 22, and the heat melts the solder 11. At the initial stage of contact between the solder 11 and the nozzle plate 21, the coil spring 33 is compressed, and the spring force of the coil spring 33 presses the solder 11 and the nozzle plate 21. When the solder 11 melts, the coil spring 33 returns to its original state, and as shown in FIG.
A gap d of about 0.1 to 0.3 mm is formed between the nozzle plate 21 and the nozzle plate 21.

Next, the solder suction block 2 is vibrated in at least one of the arrow b direction (horizontal direction) and the front-back direction while starting vacuuming with the vacuum pump. As a result, the excess solder is completely sucked by the suction nozzle 24. Excess solder is discharged through the suction nozzle 24, the manifold 25, the hole 27, and the joint pipe 28.
In this way, it is possible to form a solder coating film having a thin film thickness without solder icicles or end face electrode solder bumps on the electrode surface. When the excess solder is sucked only by vacuuming, that is, when the block 2 is sucked without vibrating, solder icicles and end surface electrode solder bumps are generated. The solder icicle means that the solder hangs down in one shape, and the end face electrode solder bump means that the electrode provided on the end face of the lower brim portion of the core of the component 1 is provided with the convex solder.

Next, after the transport block 3 is lifted and returned to the original state, the transport pallet 12 is removed from the work support plate 34, and the process is moved to the next step. The method of solder coating the electrodes of the coil component according to the present invention is not limited to the above-mentioned embodiment, and can be variously modified within the scope of the gist. In particular, the vibration direction of the solder suction block 2 is not limited to the front-rear direction or the left-right direction,
The coil component may be in any direction other than the front-rear direction or the left-right direction as long as it is substantially parallel to the electrode surface, and the core shape of the coil component is not limited to the hourglass shape as in the above embodiment.

Further, in the above-described embodiment, the excess solder melted is absorbed between the component 1 and the nozzle plate 21 by 0.1
Although a gap d of ~ 0.3 mm is provided, the gap d
It is also possible to vibrate the nozzle plate 21 in a state where the component 1 is in contact with the nozzle plate 21 without providing. in this case,
If the component 1 is strongly pressed against the nozzle plate 21, vibration or
It is not preferable because it does not absorb smoothly.

[0015]

As is apparent from the above description, according to the present invention, since the hump-shaped solder formed on the electrode surface is melted into a state where it is easily absorbed, the excess solder is absorbed by the suction nozzle. A thin solder coating film can be formed on the electrode surface. Further, when sucking the excess solder with the suction nozzle, the suction nozzle is vibrated in a direction substantially parallel to the electrode surface, so that the excess solder is completely sucked and the solder icicle and the end surface electrode solder bump can be suppressed. it can. As a result, the external dimension accuracy of the coil component is improved, and when mounting the coil component on a printed circuit board or the like, it is possible to reduce the inclination of the component, the temporary attachment failure of the component to the printed circuit board, the occurrence of the tombstone phenomenon, etc. it can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a method of solder coating an electrode of a coil component according to the present invention.

FIG. 2 is a cross-sectional view showing the procedure following FIG.

FIG. 3 is a cross-sectional view showing the procedure following FIG.

FIG. 4 is a cross-sectional view showing a state of solder coating on electrodes of a conventional coil component.

[Explanation of symbols]

1 ... Coil parts 2 ... Solder suction block 3 ... Transport block 11 ... Solder 21 ... Nozzle plate 22 ... Intermediate heat transfer plate 23 ... Hot plate 24 ... Suction nozzle 25 ... Manifold 26 ... Heater 31 ... Base plate 32 ... Shaft 33 ... Coil spring 34 ... Work support plate

Claims (2)

(57) [Claims] 1. A method of melting a hump-shaped solder formed on an electrode surface of a coil component, and then vibrating a suction nozzle close to or in contact with the electrode surface in a direction substantially parallel to the electrode surface, A method for coating a solder on an electrode of a coil component, wherein excess solder is absorbed from the molten solder by a suction nozzle. 2. A hump-shaped solder formed on an electrode surface of a coil component is brought into contact with a nozzle plate of a surplus solder suction device,
A step of melting the hump-shaped solder that has come into contact with the nozzle plate with a heating means provided in the surplus solder sucking device, and bringing a suction nozzle provided in the nozzle plate close to or in contact with the electrode surface, And a step of sucking excess solder from the molten solder with the suction nozzle while vibrating in a direction substantially parallel to the above. A method for coating solder on an electrode of a coil component, comprising: