JP2008078538A - Capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress thermal deterioration in a capacitor element formed of a film made of resin, and to improve vibration resistance. <P>SOLUTION: A capacitor has: a ceiled cylindrical case 1; the capacitor element 2 stored in the case 1; lead bodies 3, 4 lead to the outside of an opening at the lower surface of the case 1 from the capacitor element 2; and a sealing element 7 that has through holes 5, 6 through which the lead bodies 3, 4 pass and is attached to the lower opening of the case 1. The capacitor element 2 has a columnar structure, where the film that has an electrode on a surface and is made of the resin is wound around a winding core 2a. A space is formed between the outer surface of the capacitor element 2 and the inner surface of the case 1. The lower portion of the winding core 2a of the capacitor element 2 is implanted in the sealing element 7. <P>COPYRIGHT: (C)2008,JPO&amp;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, the outer periphery of the capacitor element is covered with the exterior resin. However, since the exterior resin is in contact with the capacitor element of the resin film, the solder melts even when the solder is mounted for a short time. Therefore, 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 improve vibration resistance.

  In order to achieve this object, the present invention includes a case with a cylindrical shape, a capacitor element housed in the case, a lead body drawn out from the lower surface opening of the case from the capacitor element, The lead body has a through hole through which the lead body passes, and a sealing body attached to the lower surface opening of the case. The capacitor element has a columnar shape in which a resin film having an electrode on the surface is wound around a core. The structure is such that a space is formed between the outer surface of the capacitor element and the inner surface of the case, and the lower part of the core of the capacitor element is implanted in a sealing body, thereby It achieves its purpose.

  As described above, the present invention is the one in which the capacitor element formed by using the resin film is housed in the celestial cylindrical case, and the high temperature applied during solder mounting is blocked by the outer case, When soldering is only required for a short time, the high temperature at the time of soldering is not easily transmitted to the capacitor element made of resinous film, and as a result, the capacitor element formed using the resinous film is thermally deteriorated. Therefore, it is possible to maintain a capacitor having excellent temperature characteristics and frequency characteristics, which are the original characteristics.

  The capacitor element has a columnar structure in which a resin film having electrodes on the surface is wound around a core, and a space is formed between the outer surface of the capacitor element and the inner surface of the case. In addition, since the lower part of the core of the capacitor element is implanted in the sealing body, the capacitor element is difficult to shake in the case, and the vibration resistance is improved.

  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 a case 1 having a cylindrical shape, a capacitor element 2 housed in the case 1, and the outside of the lower surface opening of the case 1 from the capacitor element 2. A lead body 3, 4 drawn out to the lead body 3, a through-hole 5, 6 through which the lead body 3, 4 penetrates, a sealing body 7 attached to the lower surface opening of the case 1, and the sealing body 7 In addition to being provided on the lower surface side, it is provided with a terminal block 8 on which the terminal portions 3a and 4a of the lead bodies 3 and 4 are mounted.

  First, the case 1 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 case 1 for electrical insulation. ing.

  In addition, a predetermined heat-insulating space is provided between the inner peripheral surface of the case 1 and the outer peripheral surface of the capacitor element 2 housed therein, and between the inner top surface of the case 1 and the upper surface of the capacitor element 2. Is provided.

  Furthermore, the case 1 and the disc-like rubber sealing body 7 are fixed by press-fitting the sealing body 7 into the lower surface opening of the case 1 and then caulking the lower part of the case 1 toward the sealing body 7. Has been.

  Next, as shown in FIG. 2, the capacitor element 2 is formed as shown in FIG. 1 in a state in which films 9 and 10 made of resin (in this embodiment, made of PET) on which aluminum electrodes 9a and 10a are vapor-deposited are superimposed. The illustrated core 2a is wound with a tension applied to form a cylindrical shape.

  As shown in FIG. 2, 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. ing. Further, as shown in FIG. 2, the electrode 10a is continuously formed in the longitudinal direction on the surface of the film 10, but the non-formed 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, the width direction (A direction in FIG. 2 and the vertical direction of the capacitor element 2 in FIG. 1)) perpendicular to the longitudinal direction. In the case of 0.3 mm to 0.8 mm), it is wound around the core 2a. At this time, the films 9 and 10 are wound around the core 2a in a tensioned state. However, the presence of the core 2a causes the films 9 and 10 to have a larger tension (core after winding). If 2a is removed, it can wind in the state which applied the big tension | tensile_strength which the cylindrical films 9 and 10 buckle inward.

  With the winding as described above, the upper side of the film 10 protrudes upward from the upper side of the film 9 in the upper surface direction of the capacitor element 2 as shown in FIG. 9 is exposed from the gap 11 due to the presence of 9.

  On the contrary, in the lower surface direction of the capacitor element 2, although not shown in FIG. 3, 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. 3, 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. Thus, the collector electrodes 12 and 13 of FIGS. 3 and 1 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. As shown in FIG. 2, 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 will be described. The lead bodies 3 and 4 are made of, for example, Cu or Sn-plated steel wire, and the sealing body 7 is made of rubber.

  As shown in FIG. 1, the through holes 5 and 6 through which the lead bodies 3 and 4 of the sealing body 7 pass are formed at portions corresponding to the lower surface of the cylindrical capacitor element 2 installed on the sealing body 7. ing. Further, the upper end of the lead body 4 penetrates the inner air core 2b portion of the winding core 2a having a cylindrical shape as shown in FIG. 1, and then the upper portion of the lead body 4 is electrically connected to the upper collector electrode 12 of the capacitor element 2. It is connected to the. At this time, since the core 2a is formed of an electrical insulator, an electrical insulation treatment with the lead body 4 is not required.

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

  In the capacitor of the present embodiment formed as described above, the capacitor element 2 formed using a resin film is housed in the celestial cylindrical case 1, and the outer peripheral surface of the capacitor element 2 and the above-mentioned Thermal insulation spaces are formed between the inner peripheral surface of the case 1 and between the upper surface of the capacitor element 2 and the ceiling surface (lower surface side) of the case 1.

  For this reason, the high temperature applied at the time of solder mounting is blocked by the outer metal case 1, so that the space (between the outer peripheral surface of the capacitor element 2 and the inner peripheral surface of the case 1 and the upper surface of the capacitor element 2 and the above-mentioned Heat transmitted through the space between the case 1 and the ceiling surface is suppressed.

  And, by such a heat shielding action, the capacitor element 2 formed using a resin film is not thermally deteriorated at the time of solder mounting, which requires only a short time. Capacitors with excellent characteristics and frequency characteristics can be maintained.

  In the present embodiment, the case 1 is made of metal and its surface is a mirror surface to improve the heat shielding effect. However, in order to insulate the lead body 4 from the upper end, the above-described case 1 is used. As described above, it is necessary to provide an insulating film on the inner surface of the case 1.

  Therefore, if this case 1 is made of synthetic resin, an insulating film for insulation between the upper ends of the lead bodies 4 is not necessary, and the synthetic resin has lower thermal conductivity than metal, The heat shielding effect can also be enhanced.

  Moreover, in this embodiment, since the lower part of the core 2a of the capacitor element 2 is press-fitted into the recess 7a of the sealing body 7 and fixed with an adhesive (not shown), it is in an implanted state. Even if vibration or impact is applied after the substrate is mounted, the capacitor element 2 is difficult to shake in the case 1 and the vibration resistance is improved.

  Furthermore, in the present embodiment, it is not necessary to provide an unnecessarily large space between the case 1 and the capacitor element 2 by passing the lead body 4 through the inner air core 2b of the winding core 2a and then pulling it upward. As a result, downsizing can be achieved. That is, unlike the present embodiment, when the core 2 a does not have the internal air core 2 b, the lead body 4 is connected between the case 1 and the capacitor element 2 in order to connect the upper end of the lead body 4 to the collector electrode 12. It is necessary to extend upward from above, and in this case, it may be necessary to provide more space than necessary between the case 1 and the capacitor element 2. As a result, the case 1 becomes large, It will increase in size.

  In the present embodiment, as described above, the films 9 and 10 are overlapped and wound around the core 2a shown in FIG. Therefore, it was confirmed that the capacitor element 2 is less likely to shrink due to heat, compared to a case where no tension is applied or a case where only a small tension is applied. That is, also from this point, the capacitor element 2 formed using the resin film is less likely to be thermally deteriorated, and a capacitor having excellent temperature characteristics and frequency characteristics, which are the original characteristics, can be maintained.

  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 wound in a state in which the films 9 and 10 made of resin (in this embodiment, made of PET) in which aluminum electrodes 9a and 10a are deposited on the surface as shown in FIG. Since it is a columnar shape, it is less likely to generate vibration due to alternating current, which causes warping as compared to a flat plate.

  (2) Further, even if a slight roaring sound is generated, the outer periphery of the capacitor element 2 is covered with a case 1 having a cylindrical shape, and the opening on the lower surface of the case 1 is a sealing body 7 and a terminal block. Since the lid 8 is covered, the roaring sound that leaks out of the case 1 is extremely small.

  As described above, according to the present invention, the capacitor element formed by using a resin film is housed in a synthetic resin dome-shaped cylindrical case, and the high temperature applied during solder mounting depends on the outer case. 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.

  The capacitor element has a columnar structure in which a resin film having electrodes on the surface is wound around a core, and a space is formed between the outer surface of the capacitor element and the inner surface of the case. In addition, since the lower part of the core of the capacitor element is implanted in the sealing body, the capacitor element is difficult to shake in the case, and the vibration resistance is improved.

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

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Case 2 Capacitor element 2a Winding core 2b Internal air core 3 Lead body 4 Lead body 5 Through-hole 6 Through-hole 7 Sealing body 8 Terminal block

Claims (5)

A celestial cylindrical case, a capacitor element housed in the case, a lead body drawn out from the lower surface opening of the case from the capacitor element, and a through-hole through which the lead body passes, A sealing body mounted on the lower surface opening of the case, and the capacitor element has a columnar structure in which a resin film having an electrode on the surface is wound around a winding core, and the outer surface of the capacitor element and the case A capacitor in which a space is formed between the inner surface of the capacitor and the lower part of the core of the capacitor element is implanted in a sealing body. The capacitor according to claim 1, wherein spaces are formed between an outer peripheral surface of the capacitor element and an inner peripheral surface of the case, and between an upper surface of the capacitor element and a ceiling surface of the case. 3. The capacitor according to claim 1, wherein the winding core has a cylindrical shape, a lead body is passed through the inner air core portion, and an upper portion of the lead body is electrically connected to an upper collector electrode of the capacitor element. The capacitor according to claim 1, wherein the case is made of metal. The capacitor according to claim 1, wherein the resin film is wound in a state where tension is applied to the core.

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