JPH05101966A - Manufacture of molded electronic component and lead frame - Google Patents

Abstract

PURPOSE:To provide a method for manufacturing an inexpensive molded electronic component which can improve a production efficiency and a lead frame. CONSTITUTION:A method for manufacturing a molded electronic component having the steps of connecting elements 9 and 10 between tie bars 2 and 3 of a lead frame and then resin-molding them to form a sheath on the elements 9 and 10 comprises the step of connecting two or more elements 9 and 10 in series between the bars 2 and 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a mold type electronic component and a lead frame with high production efficiency.

[0002]

2. Description of the Related Art Electronic components such as tantalum capacitors and film capacitors are manufactured by, for example, a molding method. To manufacture using the molding method, a metal lead frame 40 having the structure shown in FIG. 7 is used. The lead frame 40 connects the tie bars 41 and 42 with a connecting portion 43 provided at an end thereof, and
And 42, a plurality of terminal portions 44 for connecting the elements are provided one by one in a row, and section bars 45 for cutting off the space between the terminal portions 44 are alternately provided. As shown in FIG. 8, after connecting the element 46 to the terminal portion 44, the subsequent processing is performed for each lead frame 40. That is, after connecting the element 46, the lead frame 40 is conveyed to a molding device, and a resin molding process is performed to form the exterior 47. After forming the outer casing 47, aging treatment or the like is performed, and the terminal portion 44 is further cut and separated from the tie bars 41 and 42.

[0003]

However, in the conventional manufacturing method using the lead frame 40, the number of elements 46 that can perform each process at one time is small, and there is a measure to narrow the pitch between the elements 46 as much as possible. There is a drawback that the effect is low and it is difficult to increase the number of products manufactured within a predetermined time.

An object of the present invention is to provide a method for manufacturing a mold type electronic component and a lead frame which are capable of improving the above drawbacks, improving the production efficiency, and being inexpensive.

[0005]

In order to achieve the above-mentioned object, the invention of claim 1 forms an exterior by forming a resin mold process after connecting elements between tie bars of a lead frame. A method of manufacturing a mold type electronic component, comprising connecting two or more elements in series between tie bars in a method of manufacturing a mold type electronic component.

The invention of claim 2 provides a lead frame in which two or more terminal portions are provided in series in a lead frame provided with terminal portions for connecting elements between tie bars. is there.

[0007]

By connecting two or more elements in series between the tie bars of the lead frame and arranging them in a plurality of rows along the tie bar, the number of elements that can be connected to one lead frame can be increased.

[0008]

EXAMPLES The present invention will be described below based on examples.
First, tantalum powder is compression molded, and at the same time the diameter is 0.25.
Fill the mm tantalum wire and pull out one end. Then, the molded body is fired to obtain 1.02 mm × 1.82 mm × 1.45 mm
Forming a porous sintered body of tantalum having a size of. After forming the sintered body, the sintered body is immersed in a 0.1% nitric acid solution,
Anodization is performed, and an oxide film that becomes a dielectric is formed on the surface.
After forming the oxide film, the sintered body is immersed in a manganese nitrate solution and heated to deposit manganese dioxide, which becomes a solid electrolyte, on the surface of the oxide film, and this process is repeated to form a manganese dioxide layer with a predetermined thickness. To do. After forming the manganese dioxide layer, the sintered body is immersed in carbon-dispersed water and dried to form a carbon layer. After forming the carbon layer, the sintered body is dipped in a conductive silver paste, and a silver paste layer is formed by a baking method to obtain a tantalum solid electrolytic capacitor element.

The lead frame 1 has a structure as shown in FIG. 1 and is made of metal such as stainless steel. That is, the rectangular tie bars 2 and 3 are connected by the connecting portion 4 provided at the end. Then, two terminal portions 5 and 6 for connecting the elements are provided in series between the tie bars 2 and 3, and a plurality of rows of the terminal portions 5 and 6 provided in series are provided along the tie bars 2 and 3. There is. Further, between the tie bars 2 and 3, section bars 7 and 8 for cutting off the rows of the terminal portions 5 and 6 provided in series are alternately provided.

Then, as shown in FIG. 2, the elements 9 and 10 are connected to the terminal portions 5 and 6 of the lead frame 1. For connection, the outermost peripheral silver paste layers of the elements 9 and 10 are fixed by using a conductive silver paste, and the tips of the extracted tantalum wires 11 are welded by resistance welding. The elements 9 and 10 are connected to the terminals 5 and 6 with the same polarity directed in the same direction.

After the elements 9 and 10 are connected to the lead frame 1, resin molding processing is performed in units of the lead frame 1 to form exteriors 12 and 13, as shown in FIG. 3, and exterior coating elements 14 and 15. Build.

After forming the outer casings 12 and 13, etching treatment or the like is performed to cut and separate the terminal portions 5 and 6 from the tie bars 2 and 3.

After separation, parts of the terminals 5 and 6 are molded to produce a solid electrolytic capacitor.

FIG. 4 shows another embodiment of the present invention in which an element is connected to the terminal portion of the lead frame 16 and an outer cover is formed to form outer cover elements 17 and 18. In this embodiment, in particular, a sub bar 21 is provided between the tie bars 19 and 20, and the tie bar 19 and the sub bar 21 are
2 between the sub bar 21 and the tie bar 20
The terminals are arranged in series one by one, and the elements are connected to these. Therefore a total of 4 between tie bars 19 and 20
A plurality of elements can be connected in series, and a plurality of these elements are arranged alternately with the section bars 22 and 23 along the tie bars 19 and 20.

FIG. 5 also shows another embodiment of the present invention. In this embodiment, the section bar is omitted, and two terminal portions arranged in series and one terminal portion are alternately arranged along the tie bars 25 and 26 between the tie bars 25 and 26 of the lead frame 24. In addition to arranging, one terminal portion is arranged to face the intermediate portion 27 between the two terminal portions. An element is connected to each terminal portion and an exterior is formed to form exterior coating elements 28 and 29. According to this embodiment, two exterior covering elements 28 and one exterior covering element 2 arranged in series are provided.
Since the distance from the lead frame 24 can be shortened, the number of elements can be increased even if the size of the lead frame 24 is relatively small.

FIG. 6 also shows another embodiment of the present invention. In this embodiment, the section bar is omitted, and two terminal portions arranged in series and three terminal portions arranged in series are provided between the tie bars 31 and 32 of the lead frame 30.
The terminals are arranged alternately along 1 and 32, and two terminal portions are arranged corresponding to the intermediate portion 33 between the three terminal portions. Then, an element is connected to each terminal portion and an exterior is formed to form exterior coating elements 34 and 35. Also in this embodiment, the number of elements that can be connected to the lead frame 30 can be increased.

Next, the number of elements per unit area of the lead frame was obtained for the examples of FIGS. 3 and 4 and the conventional example of FIG. The results are shown in Table 1.

[0018]

[Table 1]

From Table 1, the numbers of elements per unit area are 2.3 and 2.5 according to Examples 1 and 2, and 1.7 according to the conventional example. 2 is about 1.35 to 1.47 times the conventional example.

[0020]

As described above, according to the manufacturing method of the invention of claim 1, since two or more elements are connected in series between the tie bars, the number of elements per unit area of the lead frame is increased. Therefore, the number of elements that can be processed at one time increases, the production efficiency can be improved, and a mold-type electronic component that can be manufactured at low cost can be obtained. Further, according to the invention of claim 2, by providing two or more terminal portions for connecting the elements between the tie bars in series, the lead used directly for carrying out the method for manufacturing the mold-type electronic component of claim 1. The frame is obtained.

[Brief description of drawings]

FIG. 1 is a plan view of a lead frame according to an embodiment of the present invention.

FIG. 2 is a plan view showing a state in which an element is connected to the lead frame shown in FIG.

FIG. 3 is a plan view showing a state in which an exterior is provided on the element of the lead frame shown in FIG.

FIG. 4 is a plan view showing a state in which an element is connected to a lead frame used in another embodiment of the present invention and an exterior is provided.

FIG. 5 is a plan view showing a state in which an element is connected to a lead frame used in another embodiment of the present invention and an exterior is provided.

FIG. 6 is a plan view showing a state in which an element is connected to a lead frame used for another embodiment of the present invention and an exterior is provided.

FIG. 7 shows a plan view of a conventional lead frame.

FIG. 8 is a plan view showing a state in which an element is connected to a conventional lead frame and an exterior is provided.

[Explanation of symbols]

1, 16, 24, 30 ... Lead frame, 2, 3, 19, 20, 25, 26, 31, 32 ... Tie bar, 5, 6 ... Terminal part, 9, 10 ... Element, 14, 15, 17, 18, 28, 29, 34, 35 ... Exterior covering element.

Claims (2)

[Claims] 1. A method of manufacturing a mold-type electronic component in which an element is connected between tie bars of a lead frame, and then a resin molding process is performed to form an exterior on the element. A method for manufacturing a mold-type electronic component, which is characterized by connecting. 2. A lead frame provided with terminal portions for connecting elements between tie bars, wherein the lead frame is provided with two or more terminal portions in series.