JP2008210823A - Lead wire and electronic component including the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To relax press-in stress caused at inserting a pull-out lead wire into a sealing material. <P>SOLUTION: A region adjacent to a round bar 1b of a planar tab terminal 1a is formed as a tapered region 12. In a boundary surface 12a between the bar and the terminal, the planar tab terminal 1a has a width A' substantially the same as the diameter B of the round bar 1b. A portion except the tapered region 12 of the planar tab terminal 1a has a wide region 13 having a width wider than that of the round bar 1b. The sealing member 4 covers the round bar 1b and does not cover the wide region 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lead wire and an electronic component including the lead wire, and relates to a lead wire used for extracting an electrode from an electronic component element and an electronic component configured using the lead wire.

  In many conventional electronic components, the electronic component elements are housed in a storage container made of metal, resin, etc. in order to protect the electronic component elements, which are the core of the operation, and to ensure and improve reliability. The opening end is sealed with a sealing material such as a resin material. At this time, for example, a lead wire is used for energizing the electronic component element.

  For example, the general structure of an aluminum electrolytic capacitor is as shown in FIG. This aluminum electrolytic capacitor is manufactured as follows. First, an etching process is performed on a high-purity aluminum foil to increase the surface area. This aluminum foil is subjected to a chemical conversion treatment to produce an anode foil in which an oxide film serving as a capacitor dielectric is formed, and an etched cathode foil. Capacitor element 2 is manufactured by winding the anode foil and the cathode foil (hereinafter collectively referred to as “electrode foil”) through a separator. Subsequently, the capacitor element 2 is impregnated with an electrolytic solution or a solid electrolyte, and the impregnated capacitor element is stored in a storage container 3 (mainly an aluminum case is used) having an open end. The opening end of the storage container is made of a sealing material 4 (an elastic rubber such as isobutylene-isoprene rubber: IIR or ethylene propylene terpolymer: EPT) having an insertion hole through which the lead wire 1 for taking out the electrode is inserted. ). A gap in the insertion hole of the sealing material 4 is sealed by inserting a lead wire 1 in which a tab terminal portion described later is bonded to the electrode foil using a method such as needle hole caulking or ultrasonic welding.

  As shown in FIG. 2A, this lead wire 1 generally includes an aluminum round bar portion 1b, a flat tab terminal portion 1a obtained by rolling a part thereof into a flat plate shape, and a round bar portion 1b. The lead wire 1c is welded to the lead wire 1c. The lead wire 1c is welded to the opposite side of the flat tab terminal portion 1a with respect to the round bar portion 1b. Most of the flat tab terminal portion 1 a is incorporated in the wound electrode foil of the capacitor element 2. The lead wire 1c has a smaller diameter than the round bar portion 1b. Since the flat tab terminal portion 1a of the lead wire 1 is formed by rolling (for example, Patent Literature 1 and Patent Literature 2), it has a width A wider than the diameter B of the round bar portion 1b. Therefore, the flat tab terminal portion 1a has a protruding portion that protrudes in the width direction from the round bar portion 1b by a length D that is half of (A-B).

Japanese Patent No. 3670856 JP 2003-347174 A

  In order to manufacture the aluminum electrolytic capacitor shown in FIG. 1, the flat tab terminal portion of the lead wire is crimped at an appropriate position of the anode foil and the cathode foil, and the electrode foil is wound to form a capacitor element. Placed in. Thereafter, the insertion hole of the sealing material 4 is inserted into the lead wire 1 so that a part of the flat tab terminal portion 1 a exposed from the capacitor element 2 and the round bar portion 1 b are covered with the sealing material 4. The insertion hole has a smaller diameter than the round bar 1b. At that time, the sealing material 4 generates a force for pushing up the flat tab terminal portion 1a in the direction of the arrow in FIG. 2B, and stress may be applied to the joint portion between the electrode foil and the flat tab terminal portion 1a. is there. In some cases, the joint between the electrode foil and the flat tab terminal portion 1a is peeled off or the electrode foil is broken, and the original action of drawing out the electrode cannot be obtained.

  In addition, in recent years, electric and electronic devices have been reduced in size and thickness, and electronic components have been correspondingly reduced in size and height. Since the space inside the electronic component has decreased due to the downsizing and reduction in height, the possibility of the stress described above is increasing.

  In addition, the reduction in the size and height of the electrode foil makes it possible to reduce the width of the electrode foil, and the bonding area between the electrode foil and the flat tab terminal portion 1a tends to be reduced. For this reason, it is important to suppress the above stress as much as possible.

In order to alleviate this stress, it is conceivable that the width A of the flat tab terminal portion 1a of the lead-out lead terminal 1 is made the same as the diameter B of the round bar portion 1b by cutting off the protruding portion protruding by rolling. However, in this case, in addition to the process of cutting off the protruding portion and the burr processing of the cut surface of the flat tab terminal portion 1a after cutting off, the man-hour is increased, and the contact area between the electrode foil and the flat tab terminal portion 1a is increased. Therefore, in joining methods such as needle hole caulking or ultrasonic welding, it is necessary to change the joining conditions.
Moreover, although the method of reducing the amount of protrusion by reducing pressure at the time of rolling of the flat tab terminal part 1a can be considered, in joining methods such as needle hole caulking and ultrasonic welding, the electrode foil and the flat tab terminal part 1a The electrical resistance of the joint portion increases, the mechanical strength becomes weaker than before, and as a result, the resistance to stress decreases.

  As described above, an object of the present invention is to provide a lead wire and an electronic component including the lead wire that can alleviate the indentation stress to the electronic component element generated when the lead wire is inserted through the sealing material. .

  Another object of the present invention is to make it easier to manufacture electronic parts by reducing the occurrence of abnormalities such as peeling of the joint between the electrode foil and the flat tab terminal and cutting of the electrode foil during the manufacture of electronic parts. Further, it is an object of the present invention to further improve the reliability of the product by manufacturing an electronic component using the lead wire of the present invention.

  In order to achieve the above object, a lead wire of the present invention is a lead wire for taking out an electrode from an electronic component element, and is a cylindrical round bar portion and a flat tab terminal portion joined to the electronic component element. And a lead wire formed on the side opposite to the flat tab terminal portion with respect to the round bar portion. The flat tab terminal portion has a wide area that is wider than the round bar portion, and at least in the vicinity of the boundary surface between the flat tab terminal portion and the round bar portion, is the same as the round bar portion. It is wide.

  The flat tab terminal portion may have a tapered region between the wide region and the boundary surface that linearly decreases in width as it approaches the round bar.

  The flat tab terminal portion may have an arc-shaped region between the wide region and the boundary surface, the arc-shaped region having a width that decreases in a curve as it approaches the round bar.

  The flat tab terminal portion may have the same width region that is continuous with the boundary surface and has the same width as the diameter of the round bar portion.

  An electronic component according to the present invention includes the above-described lead wire, an electronic component element joined to the flat tab terminal portion of the lead wire, a storage container for storing the electronic component element and the lead wire, and the storage container. And a sealing material for sealing the opening. And while the said round bar part is coat | covered with the said sealing material, the said wide area | region of the said flat tab terminal part is not coat | covered with the said sealing material.

  According to the present invention, since the flat tab terminal portion has the same width as the round bar portion in the vicinity of the boundary surface between the flat tab terminal portion and the round bar portion, the sealing material covers the round bar portion, and the flat tab terminal Since the wide region of the part is not covered, the stress applied to the electronic component element when the lead wire is inserted into the sealing material can be reduced. Therefore, it is possible to reduce the occurrence of abnormalities such as peeling of the joint between the electrode foil and the flat tab terminal and cutting of the electrode foil at the time of manufacturing the electronic component, thereby making it easier to manufacture the electronic component. Therefore, the reliability of the product can be improved.

  In addition, the thickness and material of the flat tab terminal part and the width of the wide area are not changed, and only the planar shape of the flat tab terminal part is changed so that no overhang is formed. The effect of relieving stress on electronic component elements can be obtained without changing the joining conditions of needle hole crimping and ultrasonic welding performed when joining parts. And can be easily introduced into the current manufacturing process.

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

(Conventional example)
FIG. 2A shows a conventional lead wire. When this is inserted through the sealing material 4, a pushing-up force as indicated by an arrow in FIG.

[Example 1]
FIG. 3A is a schematic diagram of a lead wire according to the first embodiment of the present invention. In the lead wire shown in FIG. 3A, the flat tab terminal portion 1a is narrowed toward the round bar portion 1b by using a tapered shape. That is, a region adjacent to the round bar portion 1b of the flat tab terminal portion 1a is a tapered region 12 (axial length L). At the boundary surface 12a between them, the width A ′ of the flat tab terminal portion 1a and the diameter B of the round bar portion 1b are substantially equal. A portion other than the tapered region 12 of the flat tab terminal portion 1a is a wide region 13 wider than the round bar portion 1b. In FIG. 3A, a portion drawn in a trapezoid near the boundary surface and a portion drawn in a triangle on both sides thereof are inclined surfaces inclined with respect to the flat tab terminal portion 1a (in the present invention, The inclined surface is a part of the flat tab terminal portion 1a). As shown in FIG. 3B, in the aluminum electrolytic capacitor including the lead wire shown in FIG. 3, the sealing material 4 having an insertion hole whose diameter is smaller than that of the round bar portion 1b covers the round bar portion 1b. However, the wide region 13 is not covered. That is, the end portion of the sealing material 4 is in contact with a part of the tapered region 12.

  According to the first embodiment, the pushing-up force at the time of insertion into the sealing material 4 becomes a component force in the upward direction of the force perpendicular to the tapered surface (indicated by an upward arrow in FIG. 3B). Therefore, the pushing force is relieved and stress on the electronic component element can be reduced. The length L of the tapered region 12 can be arbitrarily determined in view of the size of the lead wire, for example, the bonding method and bonding state with the electrode foil, but at least the sealing material 4 contacts. It is desirable that it is longer than the region (the upper end of the tapered region 12 is outside the sealing material 4).

[Example 2]
FIG. 4A is a schematic diagram of a lead wire according to the second embodiment of the present invention. In the lead wire shown in FIG. 4A, a part of the outer periphery of the flat tab terminal portion 1a has a circular arc shape 14, and all portions closer to the round bar portion 1b than the circular arc shape portion 14 have the same width A ′. (Same width region 15). That is, the width of the boundary surface 15a with the round bar portion 1b of the same width region 15 is A ', and the width A' of the same width region 15 is substantially equal to the diameter B of the round bar portion 1b. At this time, the sealing material 4 covers the round bar portion 1 b but does not cover the wide region 13 due to the presence of the same width region 15. That is, the end portion of the sealing material 4 is in contact with the same width region 15. As a result, as shown in FIG. 4B, when the lead wire is inserted into the sealing material 4, the flat tab terminal portion 1a is not subjected to a pushing force due to the same width region of the flat tab terminal. The portion where the circular arc shape 14 is provided can be arbitrarily determined in view of the size of the lead wire, for example, the bonding method and bonding state with the electrode foil, but at least away from the region where the sealing material 4 abuts. It is desirable that

[Example 3]
FIG. 5 is a schematic view of a lead wire according to the third embodiment of the present invention. In the lead wire shown in FIG. 5, a part of the flat tab terminal portion 1 a has a stepped shape 17, and the portion closer to the round bar portion 1 b than the portion of the stepped shape 17 has the same width A ′ (same width region 18). It has become. That is, the width of the boundary surface 18a with the round bar portion 1b of the same width region 18 is A ', and the width A' of the same width region 18 is substantially equal to the diameter B of the round bar portion 1b. At this time, the sealing material 4 covers the round bar portion 1 b due to the presence of the same width region 18, but does not cover the wide region 13. That is, the end of the sealing material 4 is in contact with the same width region 18. The length dimension for providing the stepped shape 17 can be arbitrarily determined in view of the size of the lead wire, for example, the bonding method and bonding state with the electrode foil, but at least the region where the sealing material 4 abuts. It is desirable to be away from the location.

[Example 4]
FIG. 6 is a schematic view of a lead wire according to Embodiment 4 of the present invention. In the lead wire shown in FIG. 6, a part of the flat tab terminal portion 1a has a stepped shape 19 via a taper shape, and the portion closer to the round bar portion 1b than the portion of the stepped shape 19 has the same width A ′. (Same width region 20). That is, the width of the boundary surface 20a with the round bar portion 1b of the same width region 20 is A ′, and the width A ′ of the same width region 20 is substantially equal to the diameter B of the round bar portion 1b. At this time, the sealing material 4 covers the round bar portion 1b due to the presence of the same width region 20, but does not cover the wide region 13. That is, the end portion of the sealing material 4 is in contact with the same width region 20. The portion where the step shape 19 is provided can be arbitrarily determined in consideration of the size of the lead wire, for example, the bonding method and bonding state with the electrode foil, but at least away from the region where the sealing material 4 abuts. It is desirable that

[Example 5]
FIG. 7 is a schematic view of a lead wire according to Embodiment 5 of the present invention. In the lead wire shown in FIG. 5, a portion of the flat tab terminal portion 1 a has a corrugated shape 21, and the portion closer to the round bar portion 1 b than the corrugated portion 21 has the same width A ′ (the same width region 22). ). That is, the width of the boundary surface 22a with the round bar portion 1b of the same width region 22 is A ', and the width A' of the same width region 22 is substantially equal to the diameter B of the round bar portion 1b. At this time, the sealing material 4 covers the round bar portion 1 b due to the presence of the same width region 22, but does not cover the wide region 13. That is, the end portion of the sealing material 4 is in contact with the same width region 22. The portion where the corrugation 21 is provided can be arbitrarily determined in view of the size of the lead wire, for example, the bonding method and bonding state with the electrode foil, but at least away from the region where the sealing material 4 abuts. It is desirable that

Using the lead wires having the structures shown in Examples 1 to 5 and the conventional example, a φ6.3 × 5.4 mmL size chip type (JIS32 type) aluminum electrolytic capacitor was produced, and a lead tab using an X-ray transmission device The number of element push-up occurrences at the joint was compared. The results are shown in Table 1. Element push-up was seen through with an X-ray transmission device, and it was determined that a flat tab terminal portion protruded from the end face of the wound electrode foil on the element head (storage container bottom side) as push-up.
In addition, the round bar part of the lead lead used in the example had a diameter of 0.96 mm, the flat tab terminal part width was 1.1 mm, and the taper part length of Example 1 was about 0.5 mm. The angle θ of the tapered portion is in the range of about 6 to 12 degrees. In the case of Example 1, the taper portion angle is preferably an acute angle as the taper portion length is shorter in order to suppress the pushing-up force of the sealing material.

  As apparent from Table 1 above, in the products using the lead wires of the present invention, the number of element push-ups is not in Examples 1 to 5, but the occurrence of element push-up is clearly suppressed compared to the number of occurrences in the conventional example. Thus, it is understood that the tab terminal portion is prevented from being pushed up when the lead-out lead terminal is inserted through the sealing material.

  In the above, an evaluation experiment was performed using a chip-type aluminum electrolytic capacitor. However, it is obvious that the same effect can be obtained for a lead-type (JIS 04 type) aluminum electrolytic capacitor having a similar structure and other electronic components.

It is the structure schematic of the aluminum electrolytic capacitor selected as an example of an electronic component. (A) is the schematic of the conventional drawer lead wire, (b) is the schematic diagram showing the state which penetrated the drawer lead wire to the sealing material. (A) is the schematic of the lead lead wire of Example 1 of this invention, (b) is the schematic diagram showing the state which penetrated the lead lead wire to the sealing material. (A) is the schematic of the lead lead wire of Example 2 of this invention, (b) is the schematic diagram showing the state which penetrated the lead lead wire to the sealing material. It is the schematic of the extraction lead wire of Example 3 of this invention. It is the schematic of the drawer lead wire of Example 4 of this invention. It is the schematic of the drawer lead wire of Example 5 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lead wire 1a Flat tab terminal part 1b Round bar part 1c Lead wire 2 Capacitor element 3 Storage container 4 Sealing material 12 Tapered area

Claims (5)

A lead wire for taking out an electrode from an electronic component element,
A cylindrical round bar,
A flat tab terminal joined to the electronic component element;
A lead wire formed on the opposite side of the flat tab terminal portion with respect to the round bar portion;
The flat tab terminal portion has a wide area that is wider than the round bar portion, and has the same width as the round bar portion at least in the vicinity of the boundary surface between the flat tab terminal portion and the round bar portion. Lead wire characterized by   2. The flat tab terminal portion has a tapered region between the wide region and the boundary surface, the tapered region having a width that decreases linearly as the round bar portion is approached. Lead wire as described.   The flat tab terminal portion has an arc-shaped region between the wide region and the boundary surface that has an arc-shaped region whose width decreases in a curved manner as it approaches the round bar portion. Lead wire as described.   The said flat tab terminal part has the same width | variety area | region which has the same width as the diameter of the said round bar part, and is following the said boundary surface. Lead wire according to item. The lead wire according to any one of claims 1 to 4,
An electronic component element bonded to the flat tab terminal portion of the lead wire;
A storage container for storing the electronic component element and the lead wire;
A sealing material for sealing the opening of the storage container,
An electronic component, wherein a round bar portion of the lead wire is covered with the sealing material, and a wide region of the flat tab terminal portion is not covered with the sealing material.

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