JPH0855766A - External electrode forming device for chip electronic parts - Google Patents

Abstract

PURPOSE:To provide an external electrode forming device for chip electronic parts in which external electrodes can be simply and accurately formed in various part bases. CONSTITUTION:When external electrodes are formed in the part bases 5, a plurality of part bases 5 are held to a holding jig 2 in advance so that a part thereof is exposed and conductive paste 3 is applied to all over the respective paste filling holes 11 of a paste casting table 10. After that, the holding jig 2 is moved toward the paste casting table 10 to immerse the exposed part of the part bases 5 into the conductive paste 3 of the paste filling holes 11. The immersing operation of the part bases 5 is performed so that the exposed part of all the respective part bases 5 comes into contact with the bottom surfaces of the paste filling holes 11. Thereby, even when the exposed dimension of the part bases 5 held to the holding jig 2 differs in each of the part bases 5, the conductive paste 3 is uniformly applied to each of the part bases 5 by bringing each of the part bases 5 into contact with the bottom surfaces 11a of the paste filling holes 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip electronic component such as a multilayer capacitor and a multilayer inductor, which is used for applying external electrodes to a component base of the electronic component when the chip electronic component is manufactured. The present invention relates to an electrode forming device.

[0002]

2. Description of the Related Art Conventionally, an external electrode forming apparatus of this type shown in FIG. 2 has been generally used.

This external electrode forming apparatus has a rubber-made holding jig 2 which is vertically moved up and down by a cylinder lift 1 and a paste casting table 4 to which a conductive paste 3 is attached. Is provided with a holding hole 6 for holding and housing one component base 5 of the chip electronic component. Here, the component base 5 means, for example, in a multilayer capacitor, a plurality of green sheets on which internal electrodes are formed are laminated, and an unfired product in which external electrodes have not been applied yet.

Using this external electrode forming device, a component substrate 5
When the conductive paste 3 is applied to the holding jig 2, one component base 5 is press-fitted into each holding hole 6 of the holding jig 2, and the lower end side of the component base 5 is exposed from the holding hole 6. On the other hand, the conductive paste 3 is attached to the paste casting table 4 with a squeegee 7 in a predetermined thickness.

When the preparation for forming the external electrodes is completed, the holding jig 2 is attached to the paste casting table 4.
It is mounted on the cylinder elevator 1 so as to face it, the cylinder elevator 1 is lowered by a predetermined stroke, and the lower end side of each component base 5 is dipped in the conductive paste 3. As a result, the conductive paste 3 is applied to the lower end side of each component substrate 5.

When the one-side coating operation is completed, the holding jig 2 is raised and the coated conductive paste 3 is dried. Next, in order to apply the conductive paste 3 to the other side of the component base 5 (the upper end side of the component base 5 in FIG. 2), the upper and lower sides of the component base 5 are replaced and held by the holding jig 2,
The same coating operation as described above is repeated. As a result, as shown in FIG. 3, the component base 5 having the outer electrodes 8 applied to both end sides is manufactured.

[0007]

By the way, in this outer electrode coating operation, in order to make the outer dimensions and the coating thickness of the outer electrode 8 coated on the component base 5 constant,
The following conditions must be considered.

That is, (1) the exposure dimension of the component base material 5 held by the holding jig 2 is adjusted to be constant, (2) each component base material 5
It is necessary to adjust the descending distance of (3) and (3) adjust the gap size of the squeegee 7 to adjust the coating thickness of the conductive paste.

However, the adjustment of the above (1) becomes troublesome because it has to be done every time the conductive paste 3 is applied to the component base 5, and the adjustments of the above (2) and (3) are various chips. The external dimensions of the component base 5 of the electronic component must be changed every time, which also complicates the external electrode forming process, resulting in insufficient adjustment accuracy.

In view of the above conventional problems, an object of the present invention is to
An object of the present invention is to provide an external electrode forming device for a chip electronic component that can easily and accurately form external electrodes on various component bases.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention according to claim 1 provides an elastic material in which a component base of a chip electronic component such as a multilayer capacitor and a multilayer inductor is respectively held in a plurality of holding holes. A holding jig and a paste casting table to which a conductive paste is attached,
In an external electrode forming apparatus for a chip electronic component, which moves the holding jig toward the paste casting table to apply a conductive paste to each of the component bases, a bottomed paste filling in which the paste casting table is filled with a conductive paste A plurality of holes are provided, and the paste filling holes are arranged to face the respective component bases held by the holding jig.

According to a second aspect of the invention, in the external electrode forming apparatus for a chip electronic component according to the first aspect, at least a part of the bottom surface of the paste filling hole is formed in a concave or convex shape.

[0013]

According to the invention of claim 1, when the external electrodes are formed on the component base material, the component base material is held in advance in the respective holding holes of the holding jig so as to partially expose the component base material, while the respective pastes of the paste casting table are held. Apply the conductive paste evenly to the filling holes. After that, the holding jig is moved toward the paste casting table, and the exposed portion of the component base is immersed in the paste filling hole. This dipping operation of the component base is performed by lowering the exposed parts of all the component bases until they come into contact with the bottom surface of the paste filling hole.

As a result, even if the exposed dimension of the component base held by the holding jig is different for each component base, each component base is brought into contact with the bottom surface of the paste filling hole.
The conductive paste is uniformly applied to the exposed portion of each component base.

Further, when the conductive paste is applied to the component bases having different sizes, a paste casting table having paste filling holes corresponding to the component bases may be prepared so that the external electrode coating operation can be performed each time. There is no need for work such as exposed dimensions of component parts and adjustment of the squeegee gap.

According to the second aspect of the present invention, since the contact area between the component base and the bottom surface of the paste filling hole is small, the component base coated with the conductive paste does not stick to the bottom surface, and the component base is retained and repaired. It does not come off from the tool.

[0017]

1, 4, 5, and 6 show an embodiment of an external electrode forming apparatus for a chip electronic component according to the present invention. FIG. 1 is a sectional view of the external electrode forming apparatus. 7 is an enlarged cross-sectional view showing an essential part, FIG. 5 is an enlarged cross-sectional view showing an example of an inserted state of a component base, FIG. 6 is an enlarged sectional view showing another example of an inserted state of a component base, and FIG. (b) (c) (d) (e) is an enlarged sectional view showing a modified example of the paste filling hole. The same components as those of the conventional example are represented by the same reference numerals.

That is, 1 is a cylinder elevator, 2 is a holding jig made of rubber which is vertically moved up and down by the cylinder elevator 1 as shown by an outline arrow, 3 is a conductive paste containing a metal powder such as Ag, and 5 Is a component base of a chip electronic component such as a multilayer capacitor, 6 is a holding hole formed at a predetermined interval in the holding jig 2, and each component base 5 is press-fitted into each holding hole 6.

Each of these members has the same structure as the conventional example, and the characteristic structure of the present invention is the structure of the paste casting table 10 to which the conductive paste 3 is applied.

That is, the paste casting table 10 has a paste filling hole 11 formed in the upper surface thereof for filling the conductive paste 3 therein. A plurality of the paste filling holes 11 are formed so as to face the component bases 5 held by the holding jig 2 in a one-to-one manner. Here, the component base 5 has a rectangular parallelepiped shape, for example, a square shape having longitudinal and lateral dimensions of 1.25 mm on both end faces in the longitudinal direction and a length dimension of 2.0.
When the size is mm, the size of the paste filling hole 11 facing this is formed in a square shape having a vertical and horizontal dimensions of 1.8 mm and a depth dimension of 0.4 mm.
That is, with respect to the end surface area of the component base 5 of 1.25 mm × 1.25 mm, the opening area of the paste filling hole 11 is 1.8 mm × 1.8 mm, and the paste thickness applied to the component base 5 is 0.55 mm. Set to a degree, and the component base 5
The width of the paste applied on both ends of is set to about 0.4 mm.

When the conductive paste 3 is applied to the component base 5 by using the external electrode forming apparatus according to this embodiment, a plurality of component bases 5 are partially preliminarily passed through the holding holes 6 as in the conventional example. Are held by the holding jig 2 so as to be exposed, while the paste filling holes 11 of the paste casting table 10 are held.
The conductive paste 3 is evenly applied to.

In this paste filling operation, the conductive paste 3 is attached to the entire paste casting table 10, and the conductive paste 3 in the portion other than each paste filling hole 11 is filled.
Is scraped off with a squeegee 7, and the conductive paste 3 is filled only in each paste filling hole 11.

When the paste filling work is completed,
The holding jig 2 is moved toward the paste casting table 10, and as shown in FIG. 4, the exposed portion of the component base 5 is inserted into the paste filling hole 11 and immersed in the conductive paste 3. The dipping operation of the component base 5 is performed by lowering the exposed parts of all the component bases 5 until they come into contact with the bottom surface 11a of the paste filling hole 11.

In this dipping operation of the component base 5, the exposed dimensions of the component base 5 held by the holding jig 2 are different from each other because they are not adjusted, and the component base 5 is changed in such a state. At the time of insertion, as shown in FIG. 5, the component base 5 having a long exposed dimension is placed on the bottom surface 11a of the paste filling hole 11.
First, and then the component base 5 having a short exposed dimension contacts the bottom surface 11a. Here, the component base 5 having the long exposed dimension resists the elastic force of the holding jig 2 until the component base 5 having the long exposed dimension contacts the bottom surface 11a and thereafter the component substrate 5 having the short exposed dimension contacts the bottom surface 11a. The inside of each holding hole 6 is moved upward. As a result, each long / short component base 5 contacts the bottom surface 11a, as shown in FIG. 4, and the immersion amount of each component base 5 in the conductive paste 3 becomes the same.

In addition to the length of the exposed dimension of each component base 5, the component base 5 may be held in the holding hole 6 in an inclined state as shown in FIG. Even in this case, since the component base 5 moves upward while the inclined surface is pressed by the bottom surface 11a, this inclined state is corrected during the upward movement, and the conductive state becomes as shown in FIG. It will be immersed in the paste 3.

When the paste application work is completed,
The holding jig 2 is moved upward by the cylinder elevator 1 to extract each component base 5 from the paste filling hole 11. As a result, the conductive paste 3 applied to the component base 5 becomes an external electrode. After the external electrode is dried, the holding jig 2 holds the component base 5 again so that the other end face side of the component base 5 faces downward, and the external electrode is also attached to the other end face side in the same procedure as described above. To form. As a result, the component base 5 coated with the external electrodes 8 as shown in FIG. 3 is formed.

As described above, according to the external electrode forming apparatus in this embodiment, the paste application width of the component base 5 is filled with the paste without adjusting the exposed dimension of the component base 5 held by the holding jig 2. It is adjusted by the depth of the hole 11, and also
The paste thickness of the component base 5 is adjusted by setting the opening area of the paste filling hole 11.

The external dimensions of the component base 5 differ depending on the type thereof, and the settings such as the paste coating width also differ. In such a case, the paste filling hole 11 of the paste casting table 10 is used to form the external forms of the various component bases 5. The paste casting table 10 may be formed separately according to the size and the like, and the paste casting table 10 may be prepared separately.

7 (a) (b) (c) (d) (e) show a modification of the paste filling hole 11, and FIG. 7 (a) shows the center of the bottom surface 11b of the paste filling hole 11. It has a recess formed in it. FIG. 7 (b) shows a bottom surface 11c having a slanted surface so that the center of the bottom surface is lowered, FIG. 7 (c) shows a bottom surface 11d bulging into a spherical shape, and FIG. 7 (d) shows Its bottom 11
In FIG. 7E, the bottom surface 11f has a corrugated shape.

According to these modifications, (a) and (b) of FIG.
As shown in (c), (d) and (e), the contact area between the component base 5 and the bottom surfaces 11b to 11f of the paste filling hole 11 becomes small.
Thus, when the component base 5 is pulled out from the paste filling hole 11, the component base 5 does not stick to the bottom surfaces 11b to 11f, and the component base 5 does not separate from the holding jig 2.

[0031]

As described above, according to the first aspect of the present invention, even if the exposed dimension of the component base held by the holding jig is different for each component base, the bottom surface of the paste filling hole is By bringing the respective component bases into contact with each other, the conductive paste can be uniformly applied to the respective component bases, and the operation thereof is also very simple. In addition, when applying conductive paste to various component bases with different dimensions, it is sufficient to prepare a paste casting table with paste filling holes corresponding to the external dimensions of this component base, etc. The work of adjusting the exposed dimension of the component base or adjusting the gap of the squeegee, which is performed every time the operation is performed, becomes unnecessary.

According to the second aspect of the present invention, since the contact area between the component base and the bottom surface of the paste filling hole is small, the component base coated with the conductive paste does not stick to the bottom surface, and the component base is retained and repaired. It does not come off from the tool.

[Brief description of drawings]

FIG. 1 is a sectional view of an external electrode forming apparatus for a chip electronic component according to the present invention.

FIG. 2 is a sectional view of a conventional external electrode forming device for a chip electronic component.

FIG. 3 is a perspective view showing a component base on which external electrodes are formed.

FIG. 4 is an enlarged cross-sectional view showing a main part of the present invention.

FIG. 5 is an enlarged cross-sectional view showing an example of an inserted state of a component base material.

FIG. 6 is an enlarged cross-sectional view showing another example of the inserted state of the component base material.

FIG. 7 is an enlarged sectional view showing a modified example of a paste filling hole.

[Explanation of symbols]

2 ... Holding jig, 3 ... Conductive paste, 5 ... Component base, 6 ...
Holding holes, 8 ... External electrodes, 10 ... Paste casting table, 11 ... Paste filling holes, 11a to 11f ... Bottom surface.

Claims (2)

[Claims] 1. A paste casting table, comprising: an elastic holding jig that holds a component base of a chip electronic component such as a multilayer capacitor and a multilayer inductor in a plurality of holding holes; and a paste casting table to which a conductive paste is attached. In an external electrode forming apparatus for a chip electronic component, which moves the holding jig toward a table to apply a conductive paste to each component base, the paste casting table has a plurality of bottomed paste filling holes filled with a conductive paste. An external electrode forming device for a chip electronic component, wherein each paste filling hole is provided so as to face each component base held by the holding jig. 2. The external electrode forming apparatus for a chip electronic component according to claim 1, wherein at least a part of the bottom surface of the paste filling hole is formed in a concave or convex shape.