JP2002025859A - Chip-type aluminum electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chip-type aluminum electrolytic capacitor which enables proper soldering in a state with a bent lead wire sinking into a trench part formed in a washer. SOLUTION: A metal case 3, accommodating a capacitor element 1a, is sealed by using a sealing member 4. A washer 5, which has the trench part 5b where lead wires 2a, 2b led out from the sealing member 4 are bent and accommodated, and is attached on a sealing member 4 side is arranged, and a plating film or a metal plate 5c is disposed on the outer surface of the trench part 5b of the washer 5. Accordingly, the plating film or the metal plate 5c is in contact with solder, when soldering is performed, proper soldering is enabled since the lead wires 2a, 2b are soldered as a result, and the chip-type aluminum electrolytic capacitor of high reliability can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip type aluminum electrolytic capacitor used as a surface mount type mounted on a substrate.

[0002]

2. Description of the Related Art FIGS. 4 (a) and 4 (b) are a front sectional view and a side sectional view, respectively, showing the structure of a conventional chip type aluminum electrolytic capacitor of this kind. In FIG. The chip-type aluminum electrolytic capacitor 7 is formed by winding an anode foil and a cathode foil (not shown) to which an anode lead 2a and a cathode lead 2b are connected, respectively, with a separator interposed therebetween. The capacitor element 1 a is housed in a bottomed cylindrical metal case 3 together with a driving electrolyte, and the open end of the metal case 3 is sealed with a sealing member 4.

Reference numeral 8 denotes an insulating seat plate mounted so as to contact the open end of the metal case 3. The seat plate 8 has a pair of lead wires 2a and 2b led out from the capacitor element 1a. And a groove 8b for accommodating a pair of lead wires 2a and 2b (bent portions are flattened) which are inserted through the hole 8a and accommodated by bending in a perpendicular direction. (Bottom surface) so that it can be surface-mounted on a substrate (not shown).

[0004]

However, in the above-described conventional chip type aluminum electrolytic capacitor 7, a pair of lead wires 2a, 2b inserted through the hole 8a of the insulating seat plate 8 is provided.
Is bent along the groove 8b provided in the seat plate 8, the bending fulcrum of the lead wires 2a, 2b is formed at only one place of the hole 8a, so that the bending fulcrum becomes almost an acute angle. The lead wires 2a, 2b once bent and stored in the groove 8b of FIG. 1 are trying to return to the original state due to the spring-back phenomenon of the bent portion, and as a result, a float 9 is generated as shown in FIG. 9, when the solder thickness is small, there is a problem that the soldering strength is reduced.

As shown in FIG. 6, such a problem is particularly prominent when the dummy terminal 10a is provided on the outer surface of the seat plate 10 (the bottom surface serving as a soldering surface). In this case, there is a risk that the solder will not contact the dummy terminal 10a, and there is a danger that this will become a major problem especially in the tendency of the solder thickness to be thin as in recent years, and it is necessary to take immediate measures. It had problems.

Therefore, in order to solve such problems, measures such as increasing the bending force of the lead wires 2a and 2b or increasing the depth of the groove 8b provided in the seat plate 8 are taken. Although it is designed to cope with the occurrence of the springback phenomenon, it is said that by taking such a measure, the lead wires 2a and 2b remain sunk in the groove 8b, and soldering cannot be performed. There was a problem that a new problem would occur.

The present invention solves such a conventional problem,
It is an object of the present invention to provide a chip-type aluminum electrolytic capacitor that can perform good soldering even when a bent lead wire sinks into a groove provided in a seat plate.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention is particularly directed to an anode foil and a cathode to which an anode lead wire and a cathode lead wire for external drawing are respectively connected. A capacitor element formed by winding a foil with a separator interposed therebetween, a bottomed cylindrical metal case containing the capacitor element together with a driving electrolyte, and the pair of lead wires are inserted therethrough. A sealing member having a hole, which seals the open end of the metal case, a hole through which a pair of lead wires led out from the sealing member is inserted, and a groove portion which bends and accommodates the lead wire inserted through the hole at right angles. Is provided on the outer surface of the chip-type aluminum electrolytic capacitor having an insulating seat plate mounted so as to be in contact with the sealing member. A plating film or a metal plate is provided on the outer surface of the groove including a part of the outer surface of the seat plate connected to the outer surface of the groove. With this configuration, the lead is inserted into the groove provided on the seat plate. Even if soldering is performed with the wire sunk, the solder comes into contact with the plating film or metal plate provided on the outer surface of the groove and is soldered, and as a result, the lead wire is also soldered The effect of the invention is that a highly reliable chip-type aluminum electrolytic capacitor can be provided.

[0009] The invention described in claim 2 of the present invention is, in particular,
According to the first aspect of the present invention, a dummy terminal is provided at both ends in a direction intersecting with the groove provided in the seat plate. With this configuration, the soldering area is increased to increase the soldering strength. The effect of being able to stably obtain is obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) Hereinafter, the first embodiment of the present invention will be described with reference to the first embodiment.

FIGS. 1 (a) and 1 (b) are a front sectional view and an enlarged view of a principal part showing the structure of a chip type aluminum electrolytic capacitor according to Embodiment 1 of the present invention, and FIG. 2 is a bottom view thereof. In FIG. 1, reference numeral 1 denotes a chip type aluminum electrolytic capacitor. This chip type aluminum electrolytic capacitor 1 has an anode foil and a cathode foil (not shown) to which an anode lead 2a and a cathode lead 2b are connected, respectively, with a separator interposed therebetween. The capacitor element 1a formed by being wound and wound is housed in a bottomed cylindrical metal case 3 together with a driving electrolyte,
The open end of the metal case 3 is sealed by a sealing member 4. The tip portions (bent portions to be described later) of the anode lead wire 2a and the cathode lead wire 2b are formed to be flat.

Reference numeral 5 denotes an insulating seat plate mounted so as to contact the open end of the metal case 3. The seat plate 5 has a pair of lead wires 2a and 2b led out from the capacitor element 1a. Are provided on the outer surface (the bottom surface in the figure) of a hole 5a through which the hole 5a is inserted and a pair of lead wires 2a and 2b inserted through the hole 5a are bent at right angles to accommodate the lead wire 2a. It is configured so that it can be surface-mounted on a substrate that does not. Reference numeral 5c denotes a plating film or a metal plate provided on the outer surface of the groove 5b provided on the seat plate 5 and a part of the outer surface of the seat plate 5 connected thereto. A pair of lead wires 2a and 2b bent are accommodated in a groove 5b provided with a groove.

By providing a plating film or a metal plate 5c on the outer surface of the groove 5b of the seat plate 5 as described above, the pair of lead wires 2a, 2b of the chip type aluminum electrolytic capacitor 1 can be formed in the groove 5b. Even when it is sunk into the substrate, when it is soldered to a substrate and mounted, the solder comes into contact with the plating film or the metal plate 5c and is soldered as a result. 2b can be reliably soldered, and a high soldering strength can be stably obtained. Therefore, the depth of the groove 5b provided in the seat plate 5 in advance in consideration of the springback of the lead wires 2a, 2b is considered. Therefore, it is possible to suppress lead floating and improve the reliability of soldering at the same time.

The plating film or metal plate 5c provided on the outer surface of the groove 5b of the seat plate 5 may be provided only on the outer surface of the groove 5b. It may be provided so as to include a part of the outer surface of the seat plate 5 to be connected. Further, whether to select a plating film or a metal plate depends on the shape, size, cost, and the like of the seat plate 5. It may be determined appropriately in consideration of the situation.

Reference numeral 5d denotes a chamfered portion provided at two corners which are both ends of one side in a direction intersecting with the groove 5b of the seat plate 5, and is provided on a side provided with such a chamfered portion 5d. If one of the anode and the cathode of the pair of lead wires 2a and 2b is determined to be arranged, the anode and the cathode can be very easily distinguished from the appearance of the assembled chip type aluminum electrolytic capacitor. It becomes.

(Embodiment 2) Hereinafter, a second embodiment of the present invention will be described with reference to Embodiment 2.

FIG. 3 is a bottom view showing the structure of a chip-type aluminum electrolytic capacitor according to Embodiment 2 of the present invention.
In the figure, reference numeral 6 denotes an insulating seat plate. The seat plate 6 has a hole 6a through which a pair of lead wires 2a and 2b are inserted, and a pair of lead wires 2a and 2b inserted through the hole 6a in a right angle direction. 6b for folding and storing in a groove, and this groove 6b
And a part of the outer surface of the seat plate 6 connected thereto is provided with a plating film or a metal plate 6c. Further, a pair of dummy terminals 6d are provided at both ends of the seat plate 6 in a direction intersecting with the groove portions 6b, and the dummy terminals 6d increase a soldering area to obtain more stable soldering strength. It will be able to do.

The first embodiment thus manufactured
(Table 1) and (Table 2) show the results of soldering the chip-type aluminum electrolytic capacitor according to Embodiment 2 to the substrate and confirming the state. The number of samples was 100 each, and the floating of the lead wires was performed under the conditions of -0.1 to +0.1 mm and the solder thickness of 100 µm.

[0019]

[Table 1]

[0020]

[Table 2]

As is clear from Tables 1 and 2, the chip-type aluminum electrolytic capacitor according to the present embodiment not only can suppress the floating of the lead wire but also is provided on the seat plate. It can be seen that soldering can be performed reliably even in a state where the lead wire sinks into the formed groove, and the soldering is excellent in reliability.

[0022]

As described above, according to the present invention, the metal case accommodating the capacitor element is sealed with the sealing member, and the sealing member is provided with the groove for bending and housing the lead wire led out from the sealing member. With a seat plate attached to the side, the plating film or metal plate is provided on the outer surface of the groove portion of this seat plate, so that even if soldering is performed with the lead wire sinking in the groove portion Highly reliable chips that lead wires are soldered reliably because the solder contacts the plating film or metal plate provided on the outer surface of the groove, resulting in stable high soldering strength A shaped aluminum electrolytic capacitor is obtained.

[Brief description of the drawings]

FIG. 1A is a front sectional view showing a configuration of a chip-type aluminum electrolytic capacitor according to a first embodiment of the present invention. FIG.

FIG. 2 is a bottom view of the same.

FIG. 3 is a bottom view showing a configuration of a chip-type aluminum electrolytic capacitor according to a second embodiment of the present invention.

FIG. 4A is a front sectional view showing the configuration of a conventional chip-type aluminum electrolytic capacitor, and FIG.

FIG. 5 is a cross-sectional view of a main part showing a state in which lead wires of a conventional chip type aluminum electrolytic capacitor are floating

FIG. 6 is a bottom view showing the configuration of a conventional chip-type aluminum electrolytic capacitor provided with dummy terminals.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chip type aluminum electrolytic capacitor 1a Capacitor element 2a Anode lead wire 2b Cathode lead wire 3 Metal case 4 Sealing member 5 Insulating seat plate 5a Hole 5b Groove 5c Plating coating or metal plate 5d Chamfered portion 6d Dummy terminal

Claims (2)

[Claims] 1. A capacitor element formed by winding an anode foil and a cathode foil to which an anode lead wire and a cathode lead wire for external drawing are respectively connected with a separator interposed therebetween, and a capacitor element formed by winding the anode foil and the cathode foil. And a bottomed cylindrical metal case containing a driving electrolyte, a sealing member having a hole through which the pair of lead wires are inserted, and sealing an open end of the metal case, and being derived from the sealing member. A chip comprising a hole through which a pair of lead wires are inserted and a groove for accommodating the lead wire inserted through the hole by bending at a right angle on the outer surface, the insulating seat plate being mounted so as to be in contact with the sealing member. In the aluminum electrolytic capacitor, the outer surface of the groove provided on the seat plate or the outer surface of the groove including a part of the outer surface of the seat plate connected to the outer surface of the groove is plated with a coating film or Chip type aluminum electrolytic capacitor with a metal plate. 2. The chip-type aluminum electrolytic capacitor according to claim 1, wherein dummy terminals are provided at both ends in a direction intersecting a groove provided in the seat plate.