JP2008078533A - Capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress thermal deterioration of a capacitor element, formed by using a resin film and to simplify a lead-out structure of an electrode. <P>SOLUTION: The capacitor is provided with an inner cases 1a and an outer case 1b of ceiled cylindrical-shaped cases having a multilayer structure designed for attaining the purpose, a capacitor element 2 housed inside the inner case 1a, and a sealer 7 mounted on a lower surface opening of the inner case 1a. The capacitor element 2 has a columnar structure, where a resin film having an electrode on its surface are wound, and at both ends of this columnar structure, collection electrodes 12 and 13 are formed. Among these electrodes, one collecting electrode 12 is electrically connected to the inner case 1a to which a terminal 4a, provided outside the outer case 1b, is electrically connected. To the other collecting electrode 13 of the capacitor element 2, a terminal 3a, provided outside the outer case 1b, has been electrically connected via a lead 3 that penetrates the sealer 7. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a capacitor.

  As a capacitor having excellent temperature characteristics and frequency characteristics, a capacitor using a resin film is in the spotlight.

That is, this capacitor has a structure in which a resin film having electrodes on its surface is wound to form a columnar capacitor element, and the outer periphery of this capacitor element is covered with an exterior resin (as related literature related to this) Is the following prior art document 1).
Japanese Patent No. 2877364

  The problem with the above conventional example is that the capacitor element is formed using a resin film, so that the capacitor element is thermally deteriorated at a high temperature during solder mounting.

  In other words, lead-free solder has been used in recent years, but since lead-flow solder has a high melting temperature, the resin film will be thermally deteriorated during this short time of solder mounting. there were.

  Of course, as described above, this capacitor element has its outer periphery covered with an exterior resin, but since the exterior resin is in contact with the capacitor element made of a resin film, the solder melts even when soldering for a short time. For this reason, the high temperature is transmitted to the capacitor element through the exterior resin, and as a result, the capacitor element is thermally deteriorated as described above.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to suppress thermal deterioration of a capacitor element formed using a resin film and to simplify an electrode lead structure.

  In order to achieve this object, the present invention is attached to the outer case, the outer case, the capacitor element housed in the inner case, and the lower surface opening of the inner case. The capacitor element has a columnar structure in which a resin film having electrodes on its surface is wound, and collector electrodes are formed at both ends of the columnar structure, and one collector electrode is A first terminal provided outside the outer case is electrically connected to the inner case, and a lead body penetrating the sealing body is provided to the other collector electrode of the capacitor element. Thus, the second terminal provided outside the outer case is electrically connected, thereby achieving the intended purpose.

  As described above, the present invention is the one in which the capacitor element formed using the resin film is housed in the outer case in the dome-shaped cylindrical shape, and the high temperature applied during solder mounting depends on the inner and outer cases. Since it is shielded, only a short time is required. At the time of solder mounting, the high temperature during solder mounting is not easily transmitted to the capacitor element of the resin film, and as a result, the capacitor element formed using the resin film is thermally deteriorated. The capacitor having excellent temperature characteristics and frequency characteristics, which are the original characteristics, can be maintained.

  Also, the electrode lead-out structure is simplified by adopting a configuration in which one collector electrode of the capacitor element is electrically connected to the first electrode outside the outer case via the inner case.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

  As shown in FIG. 1, the capacitor according to the present embodiment includes an outer case 1a, 1b, and a capacitor element housed in the inner case 1a. 2, a sealing body 7 attached to the lower surface openings of the inner and outer cases 1 a and 1 b, and a terminal block 8 provided on the lower surface side of the sealing body 7 and equipped with terminals 3 a and 4 a. In the following, these components will be described sequentially.

  First, the outer case 1b is made of a metal such as aluminum, and is formed in a cylindrical shape, and a resin film (not shown) is provided on the outer surface of the outer case 1b for electrical insulation. It has been. The lower surface opening of the outer case 1b is caulked and fixed to the outer peripheral surface of the sealing body 7 with an adhesive (not shown).

  An inner case 1a is provided inside the outer case 1b, and a predetermined heat insulating space is provided between the outer peripheral surfaces of the outer cases 1a and 1b and between the top surfaces.

  The inner case 1a is made of metal such as aluminum, and a heat insulating space is provided between the outer peripheral surface and the capacitor element 2 housed therein.

  Further, the lower surface opening of the inner case 1a is embedded in the upper surface of the sealing body 7, and is fixed with an adhesive (not shown) in this state.

  Next, the capacitor element 2 is wound in a state in which the films 9 and 10 made of resin (in this embodiment, made of PET) on which the electrodes 9a and 10a made of aluminum are vapor-deposited on the surface as shown in FIG. It is a cylindrical shape.

  As shown in FIG. 3, the electrode 9a is continuously formed in the longitudinal direction on the surface of the film 9, but the non-forming portion 9b of the electrode 9a is continuously formed in the longitudinal direction on the upper side in FIG. Is formed. Further, as shown in FIG. 3, the electrode 10a is continuously formed in the longitudinal direction on the surface of the film 10, but the non-forming portion 10b of the electrode 10a is continuously formed in the longitudinal direction on the lower side in FIG. Has been.

  When such films 9 and 10 are wound in an overlapped state, they are slightly (in this embodiment) in the width direction orthogonal to the longitudinal direction (the A direction in FIG. 3 and the vertical direction of the capacitor element 2 in FIG. 1). (0.3 mm to 0.8 mm).

  As a result, as shown in FIG. 4, in the upper surface direction of the capacitor element 2, the upper side of the film 10 protrudes upward from the upper side of the film 9. Is exposed.

  On the contrary, in the lower surface direction of the capacitor element 2, although not shown in FIG. 4, the lower side of the film 9 protrudes downward from the lower side of the film 10, and from the gap due to the presence of the film 10 in the downward protruding portion. The electrode 9a is exposed.

  In the capacitor element 2 of this embodiment, as shown in FIG. 4, a multi-component metallicon metal containing Zn, Sn and Cu is sprayed on the electrode 10a exposed on the upper surface and the electrode 9a exposed on the lower surface, respectively. Thereby, the collector electrodes 12 and 13 of FIGS. 1 to 3 are formed.

  Although the capacitor element 2 is not shown, the outer periphery of the capacitor element 2 has an electrically insulating structure by continuously winding the portions of the films 9 and 10 where the electrodes 9a and 10a are not provided several times. ing. Further, as shown in FIG. 3, the electrode 10a of the film 10 has a fuse function by forming a narrow portion 10c by grooves a from both sides periodically in the longitudinal direction and in a direction perpendicular to the longitudinal direction. It comes to let you.

  Next, the lead bodies 3 and 4 and the sealing body 7 extending upward from the terminals 3a and 4a will be described. These lead bodies 3 and 4 are made of, for example, Cu or Sn-plated steel wire. 7 is made of rubber.

  The through holes 5 and 6 through which the lead bodies 3 and 4 of the sealing body 7 pass are formed in a portion corresponding to the lower surface of the cylindrical capacitor element 2. In addition, the upper end of the lead body 4 is bent toward the outside of the capacitor element 2 at the outer peripheral portion of the lower surface of the capacitor element 2, and then connected to the inner peripheral surface of the inner case 1a by spot welding. ing.

  Further, the upper end of the lead body 3 is bent in the horizontal direction on the lower surface of the capacitor element 2, and this bent portion is connected to the collector electrode 13 on the lower surface of the capacitor element 2 by spot welding. It has been configured.

  The structure shown in FIG. 1 is formed from the state shown in FIG.

  That is, the capacitor element 2 is accommodated in the inner case 1a. At that time, first, the collector electrode 12 on the upper side of the capacitor element 2 and the ceiling surface of the inner case 1a are electrically connected by a conductive adhesive or welding. Next, the upper end of the lead body 3 is connected to the collector electrode 13 below the capacitor element 2 in that state by spot welding. The upper end of the lead body 4 is connected to the inner peripheral surface of the inner case 1a by spot welding.

  Thereafter, the lower ends of the lead bodies 3 and 4 are penetrated downward through the through-holes 5 and 6 of the sealing body 7, and then bent outward in the horizontal direction on the lower surface side of the terminal block 8, respectively. Become.

  In the capacitor of the present embodiment formed as described above, the capacitor element 2 formed using a resin film is housed in the inner case 1a having a celestial tube shape, and the outer peripheral surface of the capacitor element 2 is A space is formed between the inner peripheral surface of the inner case 1a.

  Moreover, the outer case 1b is covered on the outer periphery of the inner case 1a, and between these, the inner cases 1b and 1a, the outer peripheral surface, and the upper surface of the inner case 1a and the ceiling surface of the outer case 1b. There is a space.

  For this reason, the high temperature applied during solder mounting is first blocked by the outer case 1b. That is, the outer case 1b is made of aluminum as described above, and both the inner and outer peripheral surfaces are substantially mirror surfaces. Therefore, the radiant heat from the outside of the outer case 1b is reflected, and a large heat shielding action is obtained here. .

  Further, since spaces are formed between the inner case 1a inside the outer case 1b, the outer peripheral surface, and between the upper surface of the inner case 1a and the ceiling surface of the outer case 1b, the outer case There is no direct heat conduction from 1b to the inner case 1a, and therefore heat is transmitted from the outer case 1b to the inner case 1a in the form of radiant heat, and here also a heat shielding action is obtained.

  Furthermore, since a space is formed between the inner case 1a and the outer peripheral surface of the capacitor element 2, heat transfer is also suppressed by this space.

  Due to such a heat shielding action, only a short time is required. At the time of solder mounting, the capacitor element 2 formed using a resin film does not thermally deteriorate, A capacitor having excellent frequency characteristics can be maintained.

  In the capacitor of the present embodiment, vibration resistance is improved.

  That is, since the collector electrode 12 on the upper side of the capacitor element 2 and the ceiling surface of the inner case 1a are electrically connected by a conductive adhesive or welding, the capacitor element 2 can be used even when vibration is applied. There is no rolling in the inner case 1a, and the vibration resistance is improved.

  Further, the capacitor according to the present embodiment can reduce the roaring sound for the following reasons (1) and (2).

  (1) The capacitor element 2 is in a state where the films 9 and 10 made of a resin (in this embodiment, made of PET) in which aluminum electrodes 9a and 10a are vapor-deposited on the surface as shown in FIGS. Since it is wound and formed into a columnar shape, it is less likely to generate vibration due to alternating current, which causes twisting compared to a flat plate shape.

  (2) Even if a slight roaring sound is generated, the outer periphery of the capacitor element 2 is doubly covered with the outer case 1a, 1b inside the dome-shaped cylinder, and further, the inner case, the outer case 1a, Since the lower surface opening of 1b is covered with the sealing body 7 and the terminal block 8, the roaring sound that leaks out of the case 1b is extremely small.

  Note that when the inner and outer cases 1a and 1b are in a vacuum state, not only the heat from outside the outer case 1b is more difficult to be transmitted to the capacitor element 2, but also the beat sound from the capacitor element 2 is further out of the outer case 1b. It becomes difficult to propagate.

  Further, if the outer case 1b is made of a synthetic resin, it has a low thermal conductivity, and heat conduction to the inner case 1a side can be further suppressed.

  As described above, the present invention is the one in which the capacitor element formed using the resin film is housed in the outer case in the dome-shaped cylindrical shape, and the high temperature applied during solder mounting depends on the inner and outer cases. Since it is shielded, only a short time is required. When soldering, the high temperature during soldering is not easily transmitted to the capacitor element made of resin film. As a result, the capacitor element formed using the resin film is heated. There is no deterioration, and a capacitor having excellent temperature characteristics and frequency characteristics, which are the original characteristics, can be maintained.

  Also, the electrode lead-out structure is simplified by adopting a configuration in which one collector electrode of the capacitor element is electrically connected to the first electrode outside the outer case via the inner case.

  Therefore, it can be used in a wide range of industrial fields.

Sectional drawing which shows the capacitor | condenser concerning one Embodiment of this invention Sectional drawing of the inner case of the capacitor | condenser concerning one Embodiment of this invention The perspective view which shows the manufacturing method of the capacitor | condenser concerning one Embodiment of this invention. The partially expanded sectional view which shows the capacitor | condenser concerning one Embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a Inner case 1b Outer case 2 Capacitor element 3 Lead body 4 Lead body 5 Through hole 6 Through hole 7 Sealing body 8 Terminal block

Claims (5)

The outer casing, which has a multi-layered structure, includes an outer case, a capacitor element housed in the inner case, and a sealing body attached to the lower surface opening of the inner case, A columnar structure in which a resin film having electrodes on the surface is wound is formed, and collector electrodes are formed at both ends of the columnar structure, and one collector electrode is electrically connected to the inner case. Electrically connects a first terminal provided outside the outer case, and a second collector electrode provided outside the outer case is connected to the other collector electrode of the capacitor element via a lead body penetrating the sealing body. Capacitor with the terminal connected electrically. The capacitor according to claim 1, wherein collector electrodes are provided at the upper and lower ends of the capacitor element having a columnar structure, and the upper collector electrode is electrically connected to the ceiling surface of the inner case. The capacitor according to claim 1, wherein a space is formed between the outer peripheral surface of the capacitor element and the inner peripheral surface of the inner case. The capacitor according to claim 1, wherein a space is formed between the inner and outer cases. The capacitor according to any one of claims 1 to 4, wherein the outer case is made of a synthetic resin.

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