JPH0563096B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a method of packaging a capacitor, particularly a multilayer capacitor.

BACKGROUND OF THE INVENTION In recent years, as electronic devices and electrical devices have become smaller, thinner, and more dense, electronic components have become more chip-based and surface-mounted.

Ceramic capacitors and solid electrolytic capacitors have been widely used as chip capacitors.

On the other hand, in the field of film capacitors, chip-shaped multilayer film capacitors with good heat resistance have been developed that use polyphenylene sulfide film as a dielectric, and have become able to withstand temperatures during soldering. Chip-shaped film capacitors are also rapidly becoming popular, partly because they have superior electrical characteristics and reliability compared to ceramic capacitors and electrolytic capacitors.

FIG. 4 is a process perspective view for explaining a conventional method for packaging a chip film capacitor by transfer molding.

In this method, the comlead 4
After welding the external electrodes 43 and 44 of the chip film capacitor element 42 to the chip film capacitor element 42 to form a multi-layer structure, are not shown)
A chip film capacitor element 42 is placed on each side, and both molds 45 and 46 are fitted together. Next, the powdered epoxy resin 49 placed in the hopper 48 is transferred to the pot 50, and after melting it, a pressure of 60 to 90 kg/cm ² is applied with the plunger 51 to transfer the epoxy resin 49 into the element housing portion 47. Fill and cure. In this way, the packaged chip film capacitor 52 is obtained.

The resin fills the pot 50 and both molds 45 and 46.
Melt and harden by heating to about 150-180℃.

FIG. 5 is a partially cutaway perspective view of a chip film capacitor 52 manufactured as described above.

The chip film capacitor element 42 has an electrode 53 made of a comb lead 41 (the electrode connected to the other electrode 43 is not shown), and is covered with an exterior body 54 made of epoxy resin.

The characteristics of the products obtained by this transfer molding are that the external dimensions have high precision and small variations. This is because the external dimensions of the product are determined by the dimensions of the element housing portion of the mold.

Problem to be Solved by the Invention However, according to this conventional method, the fifth
The thickness _t2 of the exterior body 54 shown in the figure is as thick as 0.3 to 0.5 mm.
Moreover, since all six sides are covered by the exterior body 54, the ratio of the thickness of the exterior body 54 to the product dimensions becomes large, which is a factor that hinders miniaturization.

In addition, in terms of manufacturing costs, the manufacturing equipment is expensive, and running costs including electricity charges are also relatively high.

In this way, it is extremely difficult to downsize chip film capacitors using the method of forming the exterior body by transfer molding, which results in a larger shape than other capacitors such as ceramic capacitors, and the manufacturing cost is high. Because they are expensive, the actual situation is that the unit price has to be higher than other capacitors.

SUMMARY OF THE INVENTION The present invention aims to provide a method that allows chip film capacitors to be made smaller and cheaper than conventional products.

Means for Solving the Problems A first method for packaging a capacitor according to the present invention is to place a laminated film capacitor element with its cut surface in contact with an ultraviolet curing resin coated on a support. In this method, the resin is cured, and then the cured ultraviolet curable resin film is peeled off from the support to form a multilayer film capacitor element having an ultraviolet curable resin exterior body on the cut surface.

In the second packaging method of the present invention, a roller with a liquid packaging material adhered to a predetermined thickness is brought into contact with a cut surface of a laminated film capacitor element to transfer the liquid onto the cut surface, and further, the laminated film is This is a method in which a liquid resin material adhered to the cut surface of a capacitor element is cured to form an exterior body.

Function In the packaging method of the present invention, the packaging is formed by transferring the packaging on the cut surface of the laminated film capacitor element. Therefore, the thickness of the exterior body can be made very thin, 0.001 to 0.15 mm, and the external dimensions of the product are approximately the same as the dimensions of the element.

Examples Examples of the method of the present invention will be described below with reference to the drawings.

Embodiment 1 FIG. 1 is a perspective view showing an example of the process of packaging a cut surface of a chip film capacitor element with an ultraviolet curing resin.

A continuous ultraviolet-transparent film sheet 1 is used as a support, and an ultraviolet curable resin is applied to a predetermined thickness using a rubber roller or the like.
An ultraviolet curing resin film 2 is formed. Then, the film capacitor element 3 is attached to the film sheet 1 so that one of its cut surfaces 4 is in contact with the ultraviolet curing resin film 2, and ultraviolet rays are irradiated with the ultraviolet lamp 5 from the opposite side of the film sheet 1 from the side on which the element 3 is attached. Then, the ultraviolet curing resin 2 is cured. Then, the film capacitor element 3 is removed from the film sheet 1 by peeling it off at the interface between the film sheet 1 and the ultraviolet curing resin film 2. As a result, an exterior body 6 made of ultraviolet curing resin is formed on one cut surface 4 of the film capacitor element 3. Then, the other cut surface 7 is also provided with an exterior body in the same manner.

In addition, as the film sheet 1, ultraviolet rays are 1
% or more, and the shape may be elongated.

Furthermore, a thin plate-shaped body that is transparent to ultraviolet rays may be used in place of the film sheet.

Embodiment 2 FIG. 2 is a perspective view showing an example of the process of forming an exterior body made of epoxy resin on a cut surface of a chip film capacitor element.

A liquid epoxy resin 9 serving as an exterior member is stretched and adhered to a rubber roller 8 to a predetermined thickness, and is brought into contact with one cut surface of the film capacitor element 3. As a result, the liquid epoxy resin 9 on the cut surface 4 of the film capacitor element 3 is transferred, and a liquid epoxy resin layer 10 is formed. Then, the liquid epoxy resin 9 is similarly transferred to the other cut surface 7 to form a resin layer.
Then, by curing the liquid epoxy resin transferred to the cut surfaces 4 and 7 of the film capacitor element 3, an exterior body made of epoxy resin is formed on the cut surfaces 4 and 7 of the film capacitor element 3.

FIG. 3 shows the structure of the chip film capacitor 31 according to the first and second embodiments described above.

This film capacitor 11 has thin exterior bodies 6 and 12 provided on the cut surfaces 4 and 7 of the film capacitor element 3, respectively. Note that 13 and 14 are external electrodes of the film capacitor 11.

The thickness t ₁ of the above exterior bodies 6 and 12 is 0.001 mm to 0.15 mm
Compared to products obtained by conventional transfer molding, the shape is 20% smaller in volume.
% to 60%, resulting in a significant reduction in size. This is the future
The method of the present invention is very effective when the film capacitor element is further miniaturized.

The equipment required for implementation is much simpler and smaller than transfer molding equipment, and less material is required to form the exterior body, reducing running costs and producing inexpensive chip film capacitors. can be obtained.

Effects of the Invention According to the method of the present invention, film capacitors can be significantly miniaturized, and the equipment required for carrying out the process is much simpler than in the case of the transfer method, and the production running cost is low. Therefore, mass productivity can also be improved.

[Brief explanation of the drawing]

FIGS. 1 and 2 are perspective views showing the main steps of an embodiment of the film capacitor packaging method according to the present invention, and FIG. 3 is a partially cutaway perspective view of a film capacitor obtained by these embodiments. be. FIG. 4 is a process perspective view showing a conventional method for packaging a film capacitor, and FIG. 5 is a partially cutaway perspective view of a film capacitor obtained by this conventional method. 1... Film sheet, 2... Ultraviolet curing resin, 3... Film capacitor element, 4, 7...
Cutting surface, 5... Ultraviolet lamp, 6... Exterior body, 8
...Rubber roller, 9 ...Liquid epoxy resin, 1
0...Liquid epoxy resin layer, 11...Film capacitor, 12...Exterior body, 13, 14...External electrode.

Claims (1)

[Scope of Claims] 1. A step of applying an ultraviolet curable resin as an exterior member onto a support, and arranging a laminated film capacitor element with its cut surface in contact with the coating film of the ultraviolet curable resin. and curing the ultraviolet curable resin by irradiation with ultraviolet rays, and then peeling off the ultraviolet curable resin at the interface with the support to produce a multilayer film capacitor element having an outer ultraviolet curable resin outer body on the cut surface. 1. A method for packaging a capacitor, the method comprising: forming a capacitor. 2. Transferring the liquid resin material onto the cut surface of the multilayer film capacitor element by bringing a roller to which the liquid exterior material is adhered to a predetermined thickness into contact with the cut surface of the multilayer film capacitor element; A method for packaging a capacitor, comprising the step of curing the liquid resin material deposited on the cut surface of a laminated film capacitor element to form an exterior body.