JP2713541B2 - Structure of package type solid electrolytic capacitor and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid electrolytic capacitor in which a capacitor element portion is packaged under a synthetic resin mold, out of a tantalum solid electrolytic capacitor or an aluminum solid electrolytic capacitor having a small size and a large capacity. And a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a package type solid electrolytic capacitor of this type is disclosed in, for example, Japanese Patent Application Laid-Open No. 60-220922, and as shown in FIGS. The anode rod 1b protruding from the chip piece 1a is joined to one of the pair of left and right thin metal plate lead terminals 2 and 3 by welding or the like, while the chip piece 1a is connected to the other. After being joined to the lead terminal 3, the whole is packaged in a synthetic resin molded part 4 having a square cross section.

The protrusions of the two lead terminals 2 and 3 from the mold 4 are formed after the molding of the mold 4.
As shown by a two-dot chain line in FIG. 21, it is bent along the lower surface of the mold part 4.

[0004]

Incidentally, in this solid electrolytic capacitor, the mold part 4 for packaging the capacitor element 1 is provided with a lower mold 5 and an upper mold 5 as shown in FIGS. Molding is performed by sandwiching with a mold 6 and injecting a synthetic resin in a molten state into the cavities 5a and 6a formed therebetween.

[0005] In this case, in the conventional solid electrolytic capacitor, a portion of the thin metal plate lead terminals 2 and 3 where the lead terminals 2 and 3 protrude from the mold portion 4 is viewed from the direction of the axis thereof. The lower half of the mold section 4 is made to have a cavity 5a in the lower mold 5 by making the two dies 5 and 6 coincide with each other on a plane including the upper face 4a and the lower face 4b of the mold section 4. The upper half of the mold part 4 is formed by the cavity 6a of the upper mold 6, respectively.

With this configuration, when molding the mold part 4, the left and right inner side surfaces 5a ', 5a ", 6a', 6a" of the cavities 5a, 6a of the two dies 5, 6 are formed.
In order to easily remove the mold portion 4 from the inside of the cavities 5a and 6a, it is necessary to provide a mold removal gradient at an appropriate angle θ. Left and right side surfaces 4 of the mold part 4
c and 4d are formed on inclined side surfaces which are inclined in opposite directions with respect to the mating surface (parting line) of both dies 5 and 6.

On the other hand, the molded part 4 for packaging the capacitor element 1 needs to have a certain thickness over the entire circumference of the capacitor element 1 in order to protect the capacitor element 1. The fact that the left and right side surfaces 4c and 4d of the mold portion 4 are formed on the inclined side surfaces that are not parallel to the left and right side surfaces of the chip piece 1a as described above means that the width width W of the mold portion 4 is large.
However, this increases by the amount of the draft, which leads to an increase in the size of the solid electrolytic capacitor.

If the width W of the mold section 4 is predetermined, the cross-sectional area of the capacitor element 1 and, consequently, the volume of the capacitor element 1 must be reduced by the mold release gradient. ,
This hinders the increase in the capacity of the solid electrolytic capacitor. Moreover, the left and right side surfaces 4 of the mold portion 4
The fact that c and 4d are formed on the inclined side surfaces that are not parallel to the left and right side surfaces of the chip piece 1a as described above means that the wall thickness of the mold section 4 over the entire circumference of the capacitor element 1 is as described above. Because it becomes uneven due to the draft angle,
In molding the molded part 4, the uneven thickness of the molded part 4 not only increases the damage to the chip 1 a of the capacitor element 1 but also increases the damage to the molded part 4.
On the other hand, when an external stress is applied, there is a problem that the chip piece 1a in the capacitor element 1 is frequently damaged due to the low dispersibility of the stress.

It is an object of the present invention to provide a structure of a solid electrolytic capacitor capable of solving these problems and a method of manufacturing the same.
Another technical problem is to improve the ease of mounting a solid electrolytic capacitor on a printed circuit board or the like.

[0010]

In order to achieve this technical object, a solid electrolytic capacitor according to the present invention comprises an anode rod projecting from a chip piece of a capacitor element formed by a pair of left and right thin metal plate lead terminals. While joining to one lead terminal, the chip piece is joined to the other lead terminal, and these portions are projected from the molded portion by a synthetic resin molded portion having a substantially rectangular cross section. In the solid electrolytic capacitor packaged as described above, the two protruding portions of the two lead terminals from the mold portion are opposed to each other at two corner portions of the chip piece when viewed from the direction of the axis. On or near a diagonal connecting the two, and substantially parallel to the diagonal. "

[0011] The manufacturing method according to the present invention is preferably arranged such that an anode rod projecting from a chip piece having a substantially rectangular cross section in a capacitor element is joined to one of a pair of left and right thin metal plate lead terminals, After joining the chip piece to the other lead terminal, these parts are packaged in a synthetic resin molded part having a substantially rectangular cross section so that the two lead terminals are packaged so as to protrude from the molded part. In the manufacturing method, a portion of the two lead terminals that protrudes from the molded portion is viewed from the direction of the axis on or near a diagonal line connecting two opposing corners of the corners of the chip piece. Is positioned substantially parallel to the diagonal line, and this portion is sandwiched between a pair of mold-forming dies. Characterized by injecting a molten synthetic resin into the chromatography. "Is intended.

[0012]

[Operation] As described above, the portion of each of the lead terminals projecting from the molded portion is defined by two opposing corners of each corner of the chip piece having a substantially rectangular cross section when viewed from the direction of the axis. By being positioned on or near the diagonal line to be connected and substantially parallel to the diagonal line, the upper and lower surfaces and both left and right surfaces of the mold portion are substantially parallel to the upper and lower surfaces and both right and left surfaces of the chip piece. The mold is inclined with respect to the mating surfaces of both molds for molding, so that the upper and lower surfaces and the left and right sides of the mold portion can be easily removed from the cavities of both molds in the mold portion. It is possible to make a draft slope for making.

[0013]

As described above, according to the present invention, the upper and lower surfaces and the left and right sides of the mold portion are substantially the same as the upper and lower surfaces and the left and right sides of the chip piece of the capacitor element in a state in which a die-cutting gradient is applied thereto. Because they can be parallel, The width of the molded part can be made smaller than in the conventional case, and the size of the solid electrolytic capacitor can be reduced.When the width of the molded part is determined in advance, the capacitor element The cross-sectional area of the chip piece can be made larger than in the conventional case, and the capacity of the solid electrolytic capacitor can be increased. . By being able to make the thickness of the mold portion substantially uniform over the entire circumference of the chip piece, damage to the chip piece during molding of the mold part can be reliably reduced, and when external stress acts on the mold part, Since the dispersibility of the stress is high, the occurrence of chip chip defects can be significantly reduced. . The mold removal gradient for the cavity of both molds in the mold part can be made larger than in the conventional case, and the mold removal property can be further improved, so the time required for molding the mold part can be shortened and the cost reduced it can. Has the effect of

[0014] On the other hand, with the structure as described in claim 2, the mounting of the solid electrolytic capacitor on a printed circuit board or the like can be carried out on both sides of the lower surface side of the mold portion.
The mounting can be performed by both the lead piece and both the second lead pieces on the side surface of the mold portion. In other words, the mounting to the printed circuit board or the like is performed on the two surfaces of the lower surface side and the side surface side of the mold portion. Therefore, the mountability on a printed circuit board or the like can be improved, and the solid electrolytic capacitor is mounted on the printed circuit board or the like with both first lead pieces. Using the second lead piece,
This has the effect that another electronic component such as another solid electrolytic capacitor can be connected in parallel.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In this figure, reference numeral 11 denotes a capacitor element composed of a chip piece 11a having a substantially rectangular cross section and an anode rod 11b protruding from the chip piece 11a, and reference numerals 12 and 13 are disposed on both sides of the capacitor element 11. A lead terminal made of a thin metal plate is shown, and these two lead terminals 12 and 13 are substantially the same as a diagonal line connecting two opposing corner portions of each corner portion of the chip piece 11a when viewed from the axial direction. The anode rod 1 of the capacitor element 11 is inclined with respect to the tip of one of the two lead terminals 12, 13.
1b by welding or the like, while the two lead terminals 1
The tip of the other lead terminal 13 is twisted and deformed so as to be parallel to the lower surface of the chip piece 11a,
The chip piece 11a is joined to this.

A portion of the capacitor element 11 and a tip portion of each of the lead terminals 12 and 13 are joined to each other by a synthetic resin molded portion 14 having a substantially rectangular cross section.
Are packaged so as to protrude from both left and right end surfaces of the mold portion 14. As shown in FIGS. 8 to 10, a pair of upper and lower dies 15 and 16 are used for packaging by the mold part 14, and the two lead terminals 12 and 13 Is carried out by injecting a molten synthetic resin into the cavities 15a and 16a of the two dies 15 and 16 in this state. In this case, the two lead terminals 12 and 13 are provided as described above. As described above, the chip piece 11a having a substantially rectangular cross section when viewed from the direction of the axis is positioned on or near a diagonal connecting two opposite corners of the chip piece 11a substantially parallel to the diagonal. Accordingly, the upper and lower surfaces 14a, 14b and the left and right sides 14c, 14d of the mold portion 14 are substantially parallel to the upper, lower, left and right sides of the chip piece 11a, Since the inclined surfaces are inclined with respect to the mating surfaces of the two molds 15 and 16 for molding the mold portion 14, the upper and lower surfaces 14a and 14b and the left and right side surfaces 14c and 14d of the mold portion 14 Therefore, it is possible to form a large draft for facilitating the removal of the dies 15 and 16 from the cavities 15a and 16a.

The lead pieces 12a, 13a of the two lead terminals 12, 13 projecting from the mold portion 14.
Is formed by bending the molding portion 14 downward along the left and right end surfaces of the molding portion 14 at the bending lines A ₁ and B ₁ after forming the molding portion 14, and further bending the molding portion at the bending lines A ₂ and B ₂ . 14 is bent along the lower surface 14b.

FIGS. 11 to 14 show a second embodiment. In the second embodiment, instead of directly connecting the other lead terminal 13 to the chip piece 11a of the capacitor element 11 as in the first embodiment,
The chip piece 11a of the capacitor element 11 and the other lead terminal 13 are electrically connected via a safety fuse wire 17 as a thermal fuse or an overcurrent fuse, or a safety fuse as a thermal fuse and an overcurrent fuse. Connected.

In the case of the second embodiment, as in the first embodiment, the portions of the two lead terminals 12 and 13 projecting from the mold portion 14 are substantially cross-sectional when viewed from the direction of the axis thereof. By being positioned substantially parallel to or on a diagonal line connecting two opposing corners of each of the corners of the square chip piece 11a,
With the upper and lower surfaces 14a, 14b and the left and right side surfaces 14c, 14d of the mold portion 14 substantially parallel to the upper and lower surfaces, the left and right side surfaces of the chip piece 11a, the upper and lower surfaces 14a, 14b and the left and right side surfaces 14c, 14
d can be provided with a large mold removal gradient for facilitating the removal of the dies 15 and 16 from the cavities 15a and 16a in the mold portion 14.

FIGS. 15 to 20 show a third embodiment. In the third embodiment, both lead terminals 12, 1
3 respectively, the first lead pieces 12a ', 13a'
The lead pieces 12a "and 13a" are integrally formed, and the two lead terminals 12 and 13 are molded at A ₁ and B _{1 to form a} molded portion 14a.
After bending downward along both left and right end faces in,
The first lead piece 1 of these two lead terminals 12 and 13
2a ', 13a' and bending lines A ₂ ', B _2' while bending so as to extend along the bottom surface 14b of the mold portion 14 in the second lead piece 12a in both the lead terminals 12, 13 ", 13a" and, Bending line A ₂ ″, B ₂ ″
The left and right side surfaces 14c, 14d of the mold portion 14 at
Of the first embodiment or the second embodiment is bent along one side surface 14c.
This is the same as the embodiment.

With the construction as in the third embodiment, the mounting of the solid electrolytic capacitor on a printed circuit board or the like can be performed by the first
Both the lead pieces 12a 'and 13a' and the second lead pieces 12a "and 13a" on the side surface 14c of the mold portion 14 can be used. In other words, mounting on a printed circuit board or the like is performed by the mold portion 14. The solid electrolytic capacitor can be mounted on a printed circuit board or the like because the mounting can be performed on two surfaces, that is, the lower surface 14b side and the side surface 14c side. , 13a ', another electronic component such as another solid electrolytic capacitor is connected in parallel using the second lead pieces 12a ", 13a" of the solid electrolytic capacitor. be able to.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view of a solid electrolytic capacitor according to a first embodiment of the present invention.

FIG. 2 is a plan view taken along the line II-II of FIG.

FIG. 3 is a side view taken along the line III-III in FIG. 1;

FIG. 4 is a sectional view taken along line IV-IV of FIG.

FIG. 5 is a sectional view taken along line VV of FIG. 1;

FIG. 6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is a perspective view of the solid electrolytic capacitor according to the first embodiment in a state before a mold section is formed.

FIG. 8 is a longitudinal sectional front view showing a state in which the mold section of the first embodiment is being formed.

FIG. 9 is a sectional view taken along line IX-IX of FIG.

FIG. 10 is a plan view taken along line XX of FIG. 8;

FIG. 11 is a perspective view of a solid electrolytic capacitor according to a second embodiment in a state before a mold section is formed.

FIG. 12 is a vertical sectional front view of a solid electrolytic capacitor according to a second embodiment.

13 is a sectional view taken along the line XIII-XIII of FIG.

14 is a sectional view taken along the line XIV-XIV in FIG.

FIG. 15 is a perspective view of a solid electrolytic capacitor according to a third embodiment in a state before a mold section is formed.

FIG. 16 is a front view of a solid electrolytic capacitor according to a third embodiment.

FIG. 17 is a plan view taken along the line XVII-XVII of FIG. 16;

FIG. 18 is a side view as viewed from XVIII-XVIII in FIG. 16;

FIG. 19 is a side view as viewed from XIX-XIX in FIG. 16;

FIG. 20 is a development view of a lead terminal in the third embodiment.

FIG. 21 is a vertical sectional front view of a conventional solid electrolytic capacitor.

FIG. 22 is a sectional view taken along line XXII-XXII of FIG. 21.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Capacitor element 11a Chip piece 11b Anode rod 12 One lead terminal 13 The other lead terminal 14 Mold part 14a Upper surface of mold part 14b Lower surface of mold part 14c, 14d Side surface of mold part 15, 16 Mold for molding part 15a, 16a Cavity 12a ', 13a' First lead piece 12a ", 13a" First lead piece

Claims (3)

(57) [Claims] 1. An anode rod projecting from a chip piece of a capacitor element is joined to one of a pair of left and right thin metal plate lead terminals, while the chip piece is
In a solid electrolytic capacitor formed by bonding to the other lead terminal and packaging these parts in a synthetic resin molded part having a substantially square cross section so that the two lead terminals protrude from the molded part, The portion of the terminal protruding from the mold portion is substantially parallel to or on a diagonal line connecting two opposing corner portions of each of the corner portions of the chip piece when viewed from the direction of the axis thereof. The structure of a packaged solid electrolytic capacitor characterized by being positioned in a vertical position. 2. A first lead piece having a portion of both lead terminals protruding from the molded portion along the lower surface of the molded portion, and a second lead having one side along both left and right side surfaces of the molded portion. 2. The structure of the package type solid electrolytic capacitor according to claim 1, wherein the structure is branched into two pieces. 3. An anode rod projecting from a chip piece having a substantially rectangular cross section in a capacitor element is joined to one of a pair of left and right thin metal plate lead terminals, and the chip piece is connected to the other lead terminal. After joining these parts, these parts are molded with a synthetic resin
In the method for manufacturing a solid electrolytic capacitor, wherein both the lead terminals are packaged so as to protrude from the mold portion, a portion of the both lead terminals protruding from the mold portion is formed on the chip piece when viewed from the direction of its axis. It is located on or near a diagonal line connecting two opposing corner portions of each of the corner portions, substantially parallel to the diagonal line, and this portion is sandwiched by a pair of mold forming molds, and A method of manufacturing a package-type solid electrolytic capacitor, characterized by injecting a molten synthetic resin into a cavity in both molds.