JP4154544B2

JP4154544B2 - Electrolytic capacitor

Info

Publication number: JP4154544B2
Application number: JP15531298A
Authority: JP
Inventors: 宏次芦野
Original assignee: Nippon Chemi Con Corp
Current assignee: Nippon Chemi Con Corp
Priority date: 1998-05-20
Filing date: 1998-05-20
Publication date: 2008-09-24
Anticipated expiration: 2018-05-20
Also published as: JPH11329906A

Description

【０００１】
【発明が属する技術分野】
この発明はねじ穴を設けた外部端子を固着する封口板を使用した電解コンデンサに関するものである。
【０００２】
【従来の技術】
図10において、コンデンサ素子２は陽極箔および陰極箔の各々を電解紙を介して巻回し周面に樹脂性の巻き止めテープ９を巻き付けて形成されている。コンデンサ素子２は、電解液を含浸して有底筒状の金属ケース３に収納される。コンデンサ素子２のタブ４は、陽極箔および陰極箔の各々と電気的に接続されコンデンサ素子２の端面から引き出される。円筒形の封口板５は、外周に環状の段差を有している。封口板５には、ねじ穴（図示しない）を設けた一対の外部端子６が貫通固定されている。タブ４は円筒形の封口板５を貫通する外部端子６に接合されている。コンデンサ素子２が振動しないように金属ケース３とコンデンサ素子２間の隙間の部分に素子固定剤７が充填されている。
【０００３】
素子固定剤７はコールタール等のように予め熱により溶融させた状態で充填し、冷めて固まらせる熱可塑性のものが使用される。また、素子固定剤７は、エポキシ樹脂等のように充填した後に熱により硬化させる熱硬化性のものを使用してもよい。金属ケース３に充填した素子固定剤７が固まると金属ケース３の開口部に封口板５が嵌め込まれる。そして、封口板５の環状の段差部分には角リング形のゴム８が配置され、この状態で金属ケース３の開口部を加締めて金属ケース３に封口板５が固定され、電解コンデンサ１が形成される。
【０００４】
【発明が解決しようとする課題】
大型の電解コンデンサは重量が重く、コンデンサバンクのように複数個を組み合わせて使用される場合には、ブスバーに固定される外部端子も大型化する。そして、外部端子に対してねじの締め付けトルクを大きくして、ブスバーに大型の電解コンデンサを強固に固定することが要求されている。ねじを締めて大型の電解コンデンサをブスバーに固定する際に封口部には過大なストレスが加わる。この場合、金属ケースに対して封口板が回転し封口部の気密性が損なわれる恐れがあり改善が望まれていた。
【０００５】
この発明は、ねじ穴を設けた外部端子を固着する封口板を使用した大型の電解コンデンサにおいて、外部端子に対するねじの締め付けトルクが大きい場合に、封口部に過大なストレスが加わらない構造の電解コンデンサを提供することを目的とする。
【０００６】
【課題を解決するための手段】
この発明の電解コンデンサは、電解紙を介して両極の電極箔を巻回し両極の電極箔にそれぞれ電気的に接続されたタブが端面から引き出されるコンデンサ素子と、ねじ穴を設けた一対の外部端子を固着する封口板と、該封口板の内面側に配置され先端に開口部を有する筒部材と、一端が開口し底面に前記筒部材の開口部と噛み合う凹部を形成する金属ケースとで構成し、前記コンデンサ素子は、前記封口板に突出して形成した筒部に同軸に嵌合されて連結された前記筒部材に収納固定され、前記筒部材が前記金属ケースの底面に形成した凹部と噛み合い構造を形成し回転不能に固定されたことを第１の特徴とする。
【０００７】
前記封口板は内面の中央部に筒部が突出し該筒部の内周面には軸方向の嵌合溝を複数設けて嵌合壁面に形成され、前記筒部材は外周面に軸方向に複数の嵌合段部を外面に設けた嵌合筒部が端部に形成され、前記嵌合筒部を前記嵌合壁面に嵌め込んで前記筒部材を前記封口板の内面側に同軸に突出して固定したことを第２の特徴とする。
【０００８】
前記噛み合い構造は前記封口板の内面側に突出して設けられ先端に矩形の突出係合部が複数隣接して断続的に形成された筒部材と、一端が開口し底面に前記突出係合部の突出係合部係合溝が形成された金属ケースとで構成したことを第３の特徴とする。
【０００９】
前記噛み合い構造は前記封口板の内面側に突出して設けられ先端に矩形の突出係合部が複数隣接して断続的に形成された筒部材と、一端が開口し前記筒部材の先端に設けられた複数の突出係合部と係合する複数の突出係合部係合溝を内周面に形成した凹部が底面の中央に形成された金属ケースとで構成したことを第４の特徴とする。
【００１０】
前記噛み合い構造は前記封口板の内面側に突出して設けられ先端に矩形の突出係合部が複数隣接して断続的に形成された筒部材と、一端が開口し前記筒部材の先端に設けられた複数の突出係合部と係合する複数の突出係合部係合溝を外周面に形成した突出部が底面の中央に形成された金属ケースとで構成したことを第５の特徴とする。
【００１１】
前記噛み合い構造は前記封口板の内面側に突出して設けられ先端に矩形の突出係合部が複数隣接して断続的に形成された筒部材と、一端が開口し前記筒部材の先端に設けられた複数の突出係合部と係合する複数の突出係合部係合溝が底面の上面に軸と交差方向に形成された金属ケースとで構成したことを第６の特徴とする。
【００１２】
【実施例】
以下、この発明を図１、図２、図３、図４の（ａ）、（ｂ）、図５の（ａ）、（ｂ）、図６、図７及び図８、図９に示す図面を用いて説明する。図１は本発明の第１の実施例を示す断面図、図２は同実施例に使用した金属ケースを開口部から見た底面図、図３は同実施例に使用した封口板と筒部材との連結状態を示す正面図、図４の（ａ）は同実施例に使用した封口板の正面図、図４の（ｂ）は（ａ）に示す封口板を開口側から見た底面図、図５の（ａ）は筒部材の上面図、図５の（ｂ）は筒部材の正面図である。図６は本発明の第２の実施例を示す断面図、図７は同実施例に使用した金属ケースを開口部から見た底面図である。図８は本発明の第３の実施例を示す断面図、図９は同実施例に使用した金属ケースを開口部から見た底面図である。また、各実施例に使用されている同符号は同じものを示している。
【００１３】
図１において、コンデンサ素子12は陽極箔および陰極箔の各々を電解紙を介して巻回し周面に樹脂性の巻き止めテープ19を巻き付けて形成されている。コンデンサ素子12の端面からは両極の電極箔にそれぞれ電気的に接続されたタブ14が引き出されている。封口板15には、ねじ穴を設けた一対の外部端子16が貫通して固着されている。封口板15の内面側では中央部分に先端に開口を有する筒部22が突出して形成されている。筒部22の内部には、封口板15に固着された外部端子16にタブ14が溶接または加締め等により接続されている。筒部材28は筒部22より僅かに径の細く両端が開口している。筒部材28は一端で筒部22に挿入し、筒部22と回転不能に同軸に嵌合されて連結されている。
【００１４】
次に、封口板15と筒部材28との連結状態を示す図３を参照する。図３において、筒部材28の外周面には嵌合側の端部から略等しい外周線上に一定の幅を持つ複数（図では４個）の係合溝24が設けられている。そして、各係合溝24の位置に対応して筒部22の先端部分には複数の係合部25が形成されている。図３では、複数の係合部25の爪（図では４個）が係合溝24に差し込まれて係合し、筒部22は筒部材28に連結されている。筒部22に筒部材28を連結した状態で筒部材28内にコンデンサ素子12が収納固定されている。
【００１５】
筒部材28の径に比べてコンデンサ素子12が小さく、筒部材28内とコンデンサ素子12間の隙間が大きい場合には、この隙間の部分に素子固定剤17が充填され、筒部材28内にコンデンサ素子12が強固に固定される。さて、筒部材28の先端部分には一定の幅、一定の長さで軸方向に矩形に突出する突出係合部27が断続的に隣接して複数形成されている。一方、図２に示すように金属ケース13の内側の底面の中央部分には凹部10が形成され、この凹部10の内周面には突出係合部27と略同じ幅を持つ軸方向の突出係合部係合溝29が断続的に隣接して複数設けられている。
【００１６】
図１の実施例では、金属ケース13の内側の底面の中央部分に形成される凹部10に対応する金属ケース13の外側の底面の中央部分は外側に突出して突出部26を形成しているが、金属ケース13に厚みのあるものを使用して、金属ケース13の内側の底面の中央部分に凹部10を形成しても凹部10に対応する金属ケース13の外側の底面に突出部26は形成されず外側の底面は平坦である。
【００１７】
さて、金属ケース13の底面に形成した凹部10には筒部材28が差し込まれると、筒部材28の先端部分に形成された複数の突出係合部27が凹部10の内周面に設けた複数の突出係合部係合溝29に係合し、筒部材28は金属ケース13の底面に形成した凹部10と噛み合い構造を形成し回転不能に固定される。こうして、金属ケース13の開口部に封口板15が嵌め込まれ、封口板15の環状の段差部分に角リング形のゴム18を配置して、この状態で金属ケース13の開口部を加締めて金属ケース13に封口板15が固定して電解コンデンサ11が形成される。
【００１８】
次に、筒部22より僅かに径の細い筒部材28を筒部22と回転不能に同軸に嵌合して連結する構造について図４の（ａ）、（ｂ）を用いて説明する。図４の（ａ）において、封口板15には、ねじ穴を設けた一対の外部端子16が貫通して固着されている。封口板15の内面側の中央部分には筒部22が突出して形成されている。図４の（ｂ）に示すように筒部22の内周面には軸方向の嵌合溝35が複数、略平行に設けられて嵌合壁面32を形成し、筒部22の先端部分には係合用の爪を有する係合部25が複数箇所に形成されている。
【００１９】
次に、図５の（ａ）、（ｂ）を参照する。筒部材28は筒部22より僅かに径が細く形成されている。筒部材28は、外周面に突出し軸方向に所定長に形成した嵌合段部37を外周面に断続的に隣接して複数設けた嵌合筒部34を一端に形成している。さて、筒部材28を筒部22と連結する前に、封口板15の外部端子16にコンデンサ素子12のタブ14を溶接または加締め等により接続しておく。この状態で嵌合筒部34を嵌合壁面32に嵌め込んで筒部材28を筒部22に回転不能に同軸に嵌合固定して筒部材28を封口板15の内面側に突出する筒部22に同軸に回転不能に連結する。筒部22に筒部材28をより強固に固定したい場合には、筒部材28内とコンデンサ素子12間の隙間の部分に素子固定剤17を充填して筒部材28内にコンデンサ素子12を確実に固定すればよい。
【００２０】
図６は本発明の第２の実施例で、金属ケースの形状が第１の実施例と異なっているのみで、他の部分は同じ構成である。図６において、金属ケース23の内側の底面の中央部分には突出部20が形成されている。突出部20の外周面には突出係合部27と略同じ幅を持つ軸方向の突出係合部係合溝39が断続的に隣接して複数設けられている。図６の実施例では、金属ケース23の内側の底面の中央部分に形成される突出部20に対応する金属ケース23の外側の底面の中央部分は凹部36となっているが、金属ケース23に厚みがあれば、金属ケース23の内側の底面の中央部分に突出部20を形成しても、突出部20に対応する金属ケース13の外側の底面に凹部36は形成されず外側の底面は平坦である。
【００２１】
次に、図７を参照する。金属ケース23に筒部22と連結した筒部材28が差し込まれると、金属ケース23の底面に形成した突出部20と係合する。即ち、筒部材28の先端部分に形成された複数の突出係合部27を突出部20の外周面に設けた複数の突出係合部係合溝39に嵌まり込んで係合し、筒部材28は金属ケース23の底面に形成した突出部20と噛み合い構造を形成し回転不能に固定される。この状態で、金属ケース23の開口部に封口板15が嵌め込まれ、封口板15の環状の段差部分に角リング形のゴム18を配置して、金属ケース23の開口部を加締めて金属ケース23に封口板15が固定され、電解コンデンサ21が形成される。
【００２２】
図８は本発明の第３の実施例で、金属ケースの形状が第１の実施例と異なっているのみで、他の部分は同じ構成である。図８において、金属ケース33の内側の底面の周囲部分には環状に突出した係合底面30が形成されている。この係合底面30に対応する金属ケース33の外側の底面の周囲部分は、図示の如く環状に凹部が形成され底面の中央部分が突出する形状となっている。そして、係合底面30の上面には突出係合部27と略同じ幅を持ち、軸と交差方向の突出係合部係合溝49が複数設けられている。図８の実施例では、係合底面30に対応する金属ケース33の外側の底面の中央部分が突出する形状となっているが、金属ケース33に厚みがあれば、金属ケース33の外側の底面は環状の凹部が形成されず（底面の中央部分が突出する形状とはならず）外側の底面は平坦である。
【００２３】
次に、図９を参照する。金属ケース33に筒部22と連結した筒部材28が差し込まれると、金属ケース33の底面に形成した係合底面30と係合する。即ち、筒部材28の先端部分に形成された複数の突出係合部27を係合底面30の上面に設けた複数の突出係合部係合溝49に嵌まり込んで係合し、筒部材28は金属ケース33の底面の周囲部分に環状に突出して形成した係合底面30と噛み合い構造を形成し回転不能に固定される。この状態で、金属ケース33の開口部に封口板15が嵌め込まれ、封口板15の環状の段差部分に角リング形のゴム18を配置して、この状態で金属ケース33の開口部を加締めて金属ケース33に封口板15が固定され、電解コンデンサ31が形成される。
【００２４】
【発明の効果】
本発明では、ねじ穴を設けた外部端子を固着する封口板の内面側に突出して先端に開口部を有するように筒部材を設けている。一端が開口した金属ケースに筒部材を収納すると筒部材の開口部は、金属ケースの底面と噛み合い構造を形成した状態となり封口される。したがって、外部端子に対するねじの締め付けトルクが大きい場合に加わる過大なストレスは筒部材と金属ケースとの噛み合い構造による接合部に加わることになり、直接、封口部に過大なストレスが加わらなくなる。そのため、外部端子に強くねじを締め付けても金属ケースに対して封口板が回転することは防止され封口部の気密性が損なわれる恐れが改善される等実用的である。
【図面の簡単な説明】
【図１】本発明の第１の実施例を示す断面図である。
【図２】同実施例に使用した金属ケースを開口部から見た底面である。
【図３】同実施例に使用した封口板と筒部材との連結状態を示す正面図である。
【図４】（ａ）は図１に使用した封口板の正面図である。（ｂ）は同封口板を開口側から見た底面図である。
【図５】（ａ）は（ｂ）に示す筒部材の上面図である。（ｂ）は図１に使用した筒部材の正面図である。
【図６】本発明の第２の実施例を示す断面図である。
【図７】同実施例に使用した金属ケースを開口部から見た底面図である。
【図８】本発明の第３の実施例を示す断面図である。
【図９】同実施例に使用した金属ケースを開口部から見た底面図である。
【図10】従来の電解コンデンサの断面図である。
【符号の説明】
１電解コンデンサ
２コンデンサ素子
３金属ケース
４タブ
５封口板
６外部端子
７素子固定剤
８ゴム
９巻き止めテープ
10 凹部
11 電解コンデンサ
12 コンデンサ素子
13 金属ケース
14 タブ
15 封口板
16 外部端子
17 素子固定剤
18 ゴム
19 巻き止めテープ
20 突出部
21 電解コンデンサ
22 筒部
23 金属ケース
24 係合溝
25 係合部
26 突出部
27 突出係合部
28 筒部材
29 突出係合部係合溝
30 係合底面
31 電解コンデンサ
32 嵌合壁面
33 金属ケース
34 嵌合筒部
35 嵌合溝
36 凹部
37 嵌合段部
39 突出係合部係合溝
49 突出係合部係合溝[0001]
[Technical field to which the invention belongs]
The present invention relates to an electrolytic capacitor using a sealing plate for fixing an external terminal provided with a screw hole.
[0002]
[Prior art]
In FIG. 10, the capacitor element 2 is formed by winding each of an anode foil and a cathode foil through electrolytic paper and winding a resinous anti-winding tape 9 around the peripheral surface. The capacitor element 2 is impregnated with an electrolytic solution and accommodated in a bottomed cylindrical metal case 3. The tab 4 of the capacitor element 2 is electrically connected to each of the anode foil and the cathode foil and is drawn out from the end face of the capacitor element 2. The cylindrical sealing plate 5 has an annular step on the outer periphery. A pair of external terminals 6 provided with screw holes (not shown) are penetrated and fixed to the sealing plate 5. The tab 4 is joined to an external terminal 6 that penetrates the cylindrical sealing plate 5. An element fixing agent 7 is filled in a gap portion between the metal case 3 and the capacitor element 2 so that the capacitor element 2 does not vibrate.
[0003]
As the element fixing agent 7, a thermoplastic material such as coal tar, which is filled in a state of being previously melted by heat and then cooled and solidified is used. The element fixing agent 7 may be a thermosetting material that is filled with an epoxy resin or the like and then cured by heat. When the element fixing agent 7 filled in the metal case 3 is hardened, the sealing plate 5 is fitted into the opening of the metal case 3. Then, a ring-shaped rubber 8 is disposed at the annular step portion of the sealing plate 5, and in this state, the opening of the metal case 3 is crimped to fix the sealing plate 5 to the metal case 3. It is formed.
[0004]
[Problems to be solved by the invention]
Large electrolytic capacitors are heavy, and when used in combination, such as a capacitor bank, the external terminals fixed to the bus bars are also enlarged. Then, it is required to increase the tightening torque of the screw with respect to the external terminal and firmly fix the large electrolytic capacitor to the bus bar. When the large electrolytic capacitor is fixed to the bus bar by tightening the screw, excessive stress is applied to the sealing portion. In this case, the sealing plate rotates with respect to the metal case, and the airtightness of the sealing portion may be impaired, and an improvement has been desired.
[0005]
The present invention relates to a large electrolytic capacitor using a sealing plate for fixing an external terminal provided with a screw hole, and an electrolytic capacitor having a structure in which excessive stress is not applied to the sealing portion when the tightening torque of the screw with respect to the external terminal is large. The purpose is to provide.
[0006]
[Means for Solving the Problems]
The electrolytic capacitor according to the present invention includes a capacitor element in which tabs that are electrically connected to the electrode foils of both electrodes are wound around the electrode foil through the electrolysis paper, and a pair of external terminals provided with screw holes. in the sealing plate for fixing a cylindrical member having an opening at the tip is disposed on the inner surface of the encapsulating port plate, one end of the metal case to form a intermesh cormorants recess and opening of the tubular member to open the bottom The capacitor element is housed and fixed in the cylindrical member that is coaxially fitted and connected to the cylindrical portion that protrudes from the sealing plate, and the cylindrical member is formed on the bottom surface of the metal case; A first feature is that an interlocking structure is formed and fixed in a non-rotatable manner.
[0007]
The sealing plate has a cylindrical portion protruding from the center of the inner surface, and a plurality of axial fitting grooves are formed on the inner peripheral surface of the cylindrical portion to form a fitting wall surface. A fitting tube portion provided on the outer surface of the fitting step portion is formed at the end, the fitting tube portion is fitted into the fitting wall surface, and the tube member projects coaxially to the inner surface side of the sealing plate. The second feature is that it is fixed.
[0008]
The meshing structure is provided so as to protrude from the inner surface side of the sealing plate and has a cylindrical member formed intermittently with a plurality of rectangular protruding engaging portions adjacent to each other at the tip, and one end opened to the bottom surface of the protruding engaging portion. A third feature is that it is configured with a metal case in which a protruding engaging portion engaging groove is formed.
[0009]
The meshing structure is provided so as to protrude from the inner surface side of the sealing plate, and a cylindrical member having a plurality of rectangular projecting engaging portions formed adjacent to each other at the tip, and one end opened and provided at the tip of the tube member. According to a fourth aspect of the present invention, there is provided a metal case in which a concave portion in which a plurality of protruding engaging portion engaging grooves engaging with a plurality of protruding engaging portions is formed in the inner peripheral surface is formed in the center of the bottom surface. .
[0010]
The meshing structure is provided so as to protrude from the inner surface side of the sealing plate, and a cylindrical member having a plurality of rectangular projecting engaging portions formed adjacent to each other at the tip, and one end opened and provided at the tip of the tube member. According to a fifth aspect of the present invention, there is provided a metal case in which a plurality of projecting engaging portion engaging grooves that engage with the plurality of projecting engaging portions are formed on a peripheral surface of the projecting portion. .
[0011]
The meshing structure is provided so as to protrude from the inner surface side of the sealing plate, and a cylindrical member having a plurality of rectangular projecting engaging portions formed adjacent to each other at the tip, and one end opened and provided at the tip of the tube member. According to a sixth aspect of the present invention, the plurality of protruding engaging portion engaging grooves that engage with the plurality of protruding engaging portions are configured by a metal case formed on the upper surface of the bottom surface in a direction intersecting the axis.
[0012]
【Example】
FIG. 1, FIG. 2, FIG. 3, FIG. 4 (a), (b), FIG. 5 (a), (b), FIG. 6, FIG. 7, FIG. Will be described. 1 is a sectional view showing a first embodiment of the present invention, FIG. 2 is a bottom view of the metal case used in the embodiment as seen from the opening, and FIG. 3 is a sealing plate and a cylindrical member used in the embodiment. FIG. 4A is a front view of the sealing plate used in the embodiment, and FIG. 4B is a bottom view of the sealing plate shown in FIG. 4A viewed from the opening side. 5A is a top view of the cylindrical member, and FIG. 5B is a front view of the cylindrical member. FIG. 6 is a sectional view showing a second embodiment of the present invention, and FIG. 7 is a bottom view of the metal case used in the embodiment as seen from the opening. FIG. 8 is a sectional view showing a third embodiment of the present invention, and FIG. 9 is a bottom view of the metal case used in the embodiment as seen from the opening. Further, the same reference numerals used in the embodiments indicate the same components.
[0013]
In FIG. 1, a capacitor element 12 is formed by winding an anode foil and a cathode foil through electrolytic paper, and winding a resinous anti-stick tape 19 around the peripheral surface. Tabs 14 electrically connected to the electrode foils of both electrodes are drawn out from the end face of the capacitor element 12. A pair of external terminals 16 provided with screw holes penetrates and is fixed to the sealing plate 15. On the inner surface side of the sealing plate 15, a cylindrical portion 22 having an opening at the tip is formed at the center portion so as to protrude. Inside the cylindrical portion 22, a tab 14 is connected to an external terminal 16 fixed to the sealing plate 15 by welding or caulking. The cylindrical member 28 is slightly narrower in diameter than the cylindrical portion 22 and is open at both ends. The cylindrical member 28 is inserted into the cylindrical portion 22 at one end, and is coaxially fitted and connected to the cylindrical portion 22 so as not to rotate.
[0014]
Next, FIG. 3 which shows the connection state of the sealing board 15 and the cylinder member 28 is referred. In FIG. 3, a plurality (four in the figure) of engagement grooves 24 having a constant width are provided on the outer peripheral surface of the cylindrical member 28 on substantially the same outer peripheral line from the end portion on the fitting side. A plurality of engaging portions 25 are formed at the distal end portion of the cylindrical portion 22 corresponding to the positions of the engaging grooves 24. In FIG. 3, claws (four in the figure) of the plurality of engaging portions 25 are inserted into the engaging grooves 24 and engaged, and the cylindrical portion 22 is connected to the cylindrical member 28. The capacitor element 12 is housed and fixed in the tubular member 28 with the tubular member 28 connected to the tubular portion 22.
[0015]
When the capacitor element 12 is smaller than the diameter of the cylindrical member 28 and the gap between the cylindrical member 28 and the capacitor element 12 is large, the element fixing agent 17 is filled in the gap portion, and the cylindrical member 28 is filled with the capacitor. The element 12 is firmly fixed. A plurality of projecting engagement portions 27 projecting in a rectangular shape in the axial direction with a certain width and a certain length are formed intermittently adjacent to the distal end portion of the cylindrical member 28. On the other hand, as shown in FIG. 2, a concave portion 10 is formed in the central portion of the bottom surface inside the metal case 13, and an axial protrusion having substantially the same width as the protruding engagement portion 27 is formed on the inner peripheral surface of the concave portion 10. A plurality of engaging portion engaging grooves 29 are provided intermittently adjacent to each other.
[0016]
In the embodiment of FIG. 1, the central portion of the outer bottom surface of the metal case 13 corresponding to the recess 10 formed in the central portion of the inner bottom surface of the metal case 13 protrudes outward to form a protruding portion 26. Even if the metal case 13 is thick and the recess 10 is formed at the center of the inner bottom surface of the metal case 13, the protrusion 26 is formed on the outer bottom surface of the metal case 13 corresponding to the recess 10. The outer bottom surface is flat.
[0017]
Now, when the cylindrical member 28 is inserted into the concave portion 10 formed on the bottom surface of the metal case 13, a plurality of projecting engaging portions 27 formed at the tip portion of the cylindrical member 28 are provided on the inner peripheral surface of the concave portion 10. of engaging the projecting engaging portion engaging groove 29, the cylindrical member 28 is formed by non-rotatably fixing the structure engages with the recess 10 formed on the bottom surface of the metal casing 13. Thus, the sealing plate 15 is fitted into the opening of the metal case 13, and the square ring-shaped rubber 18 is disposed at the annular step portion of the sealing plate 15, and the opening of the metal case 13 is crimped in this state to form the metal. A sealing plate 15 is fixed to the case 13 to form the electrolytic capacitor 11.
[0018]
Next, a structure in which a cylindrical member 28 having a diameter slightly smaller than that of the cylindrical portion 22 is fitted and connected to the cylindrical portion 22 so as to be non-rotatable will be described with reference to FIGS. In FIG. 4A, a pair of external terminals 16 provided with screw holes are passed through and fixed to the sealing plate 15. A cylindrical portion 22 protrudes from the central portion on the inner surface side of the sealing plate 15. As shown in FIG. 4 (b), a plurality of axial fitting grooves 35 are provided substantially in parallel on the inner peripheral surface of the cylindrical portion 22 to form a fitting wall surface 32. The engaging portions 25 having engaging claws are formed at a plurality of locations.
[0019]
Next, reference is made to (a) and (b) of FIG. The cylindrical member 28 is formed to have a slightly smaller diameter than the cylindrical portion 22. The cylindrical member 28 has, at one end, a fitting cylinder portion 34 provided with a plurality of fitting step portions 37 that protrude from the outer circumferential surface and have a predetermined length in the axial direction and are intermittently adjacent to the outer circumferential surface. Now, before connecting the tubular member 28 to the tubular portion 22, the tab 14 of the capacitor element 12 is connected to the external terminal 16 of the sealing plate 15 by welding or caulking. In this state, the fitting cylinder portion 34 is fitted to the fitting wall surface 32, and the cylinder member 28 is coaxially fitted and fixed to the cylinder portion 22 in a non-rotatable manner so that the cylinder member 28 projects to the inner surface side of the sealing plate 15. Connected to 22 coaxially and non-rotatably. When it is desired to more firmly fix the tubular member 28 to the tubular portion 22, the gap between the tubular member 28 and the capacitor element 12 is filled with the element fixing agent 17 so that the capacitor element 12 is securely placed in the tubular member 28. Fix it.
[0020]
FIG. 6 shows a second embodiment of the present invention, in which the shape of the metal case is only different from that of the first embodiment, and the other parts have the same configuration. In FIG. 6, a protruding portion 20 is formed at the central portion of the bottom surface inside the metal case 23. On the outer peripheral surface of the projecting portion 20, a plurality of axial projecting engaging portion engaging grooves 39 having substantially the same width as the projecting engaging portion 27 are provided intermittently adjacent to each other. In the embodiment of FIG. 6, the central portion of the outer bottom surface of the metal case 23 corresponding to the protruding portion 20 formed in the central portion of the inner bottom surface of the metal case 23 is a recess 36, If there is a thickness, even if the protrusion 20 is formed at the center of the bottom surface inside the metal case 23, the recess 36 is not formed on the bottom surface outside the metal case 13 corresponding to the protrusion 20, and the outer bottom surface is flat. It is.
[0021]
Reference is now made to FIG. When the cylindrical member 28 connected to the cylindrical portion 22 is inserted into the metal case 23, the protruding portion 20 formed on the bottom surface of the metal case 23 is engaged. That is, the plurality of projecting engagement portions 27 formed at the distal end portion of the cylindrical member 28 are fitted into and engaged with the plurality of projecting engagement portion engaging grooves 39 provided on the outer peripheral surface of the projecting portion 20, thereby 28 engages with the protrusion 20 formed on the bottom surface of the metal case 23 to form a meshing structure and is fixed so as not to rotate. In this state, the sealing plate 15 is fitted into the opening of the metal case 23, the square ring-shaped rubber 18 is disposed on the annular step portion of the sealing plate 15, and the opening of the metal case 23 is crimped to form the metal case. The sealing plate 15 is fixed to 23, and the electrolytic capacitor 21 is formed.
[0022]
FIG. 8 shows a third embodiment of the present invention. The shape of the metal case is only different from that of the first embodiment, and the other parts have the same configuration. In FIG. 8, an engagement bottom surface 30 projecting in an annular shape is formed around the inner bottom surface of the metal case 33. A peripheral portion of the outer bottom surface of the metal case 33 corresponding to the engagement bottom surface 30 has a shape in which a concave portion is formed in an annular shape and a central portion of the bottom surface protrudes as shown in the figure. A plurality of protruding engaging portion engaging grooves 49 having substantially the same width as the protruding engaging portion 27 and intersecting with the shaft are provided on the upper surface of the engaging bottom surface 30. In the embodiment of FIG. 8, the central portion of the outer bottom surface of the metal case 33 corresponding to the engagement bottom surface 30 protrudes, but if the metal case 33 is thick, the bottom surface on the outer side of the metal case 33. An annular recess is not formed (the shape does not protrude from the center of the bottom surface), and the outer bottom surface is flat.
[0023]
Reference is now made to FIG. When the cylindrical member 28 connected to the cylindrical portion 22 is inserted into the metal case 33, it engages with the engagement bottom surface 30 formed on the bottom surface of the metal case 33. That is, the plurality of projecting engagement portions 27 formed at the distal end portion of the cylindrical member 28 are fitted into and engaged with the plurality of projecting engagement portion engaging grooves 49 provided on the upper surface of the engagement bottom surface 30, thereby 28 is engaged with an engagement bottom surface 30 formed to project annularly around the bottom surface of the metal case 33, and is fixed to be non-rotatable. In this state, the sealing plate 15 is fitted into the opening of the metal case 33, and the square ring-shaped rubber 18 is disposed on the annular step portion of the sealing plate 15, and the opening of the metal case 33 is crimped in this state. Thus, the sealing plate 15 is fixed to the metal case 33, and the electrolytic capacitor 31 is formed.
[0024]
【The invention's effect】
In the present invention, the cylindrical member is provided so as to protrude to the inner surface side of the sealing plate to which the external terminal provided with the screw hole is fixed and to have an opening at the tip. When the cylindrical member is housed in a metal case having one end opened, the opening of the cylindrical member is engaged with the bottom surface of the metal case to form a sealed structure and sealed. Therefore, excessive stress applied when the tightening torque of the screw with respect to the external terminal is large is applied to the joint portion formed by the meshing structure between the cylindrical member and the metal case, and excessive stress is not directly applied to the sealing portion. Therefore, even if the screw is strongly tightened to the external terminal, the sealing plate is prevented from rotating with respect to the metal case, and the possibility that the airtightness of the sealing portion is impaired is improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of the present invention.
FIG. 2 is a bottom view of the metal case used in the embodiment as seen from the opening.
FIG. 3 is a front view showing a connection state between a sealing plate and a cylindrical member used in the example.
4A is a front view of the sealing plate used in FIG. 1. FIG. (B) is the bottom view which looked at the sealing plate from the opening side.
5A is a top view of the cylindrical member shown in FIG. 5B. (B) is a front view of the cylindrical member used in FIG.
FIG. 6 is a cross-sectional view showing a second embodiment of the present invention.
FIG. 7 is a bottom view of the metal case used in the embodiment as seen from the opening.
FIG. 8 is a cross-sectional view showing a third embodiment of the present invention.
FIG. 9 is a bottom view of the metal case used in the same embodiment as seen from the opening.
FIG. 10 is a cross-sectional view of a conventional electrolytic capacitor.
[Explanation of symbols]
1 Electrolytic Capacitor 2 Capacitor Element 3 Metal Case 4 Tab 5 Sealing Plate 6 External Terminal 7 Element Fixing Agent 8 Rubber 9 Winding Tape
10 Recess
11 Electrolytic capacitor
12 Capacitor element
13 Metal case
14 tabs
15 Sealing plate
16 External terminal
17 Element fixing agent
18 Rubber
19 Winding tape
20 Protrusion
21 Electrolytic capacitor
22 Tube
23 Metal case
24 engaging groove
25 Engagement part
26 Protrusion
27 Protruding engagement part
28 Tube member
29 Projection engagement part engagement groove
30 Engagement bottom
31 Electrolytic capacitor
32 Mating wall
33 Metal case
34 Mating tube
35 Mating groove
36 Recess
37 Mating step
39 Projection engagement part engagement groove
49 Projection engagement part engagement groove

Claims

Capacitor elements in which the electrode foils of both electrodes are wound through electrolytic paper and the tabs electrically connected to the electrode foils of both electrodes are pulled out from the end faces, and a sealing plate for fixing a pair of external terminals provided with screw holes, a cylindrical member having an opening at the tip is disposed on the inner surface of the encapsulating port plate, one end is constituted by a metal case which forms a intermesh cormorants recess and opening of the tubular member to the open bottom, said capacitor element The cylindrical member is housed and fixed in the cylindrical member that is coaxially fitted and connected to the cylindrical portion that protrudes from the sealing plate, and the cylindrical member forms a meshing structure with the concave portion formed in the bottom surface of the metal case and cannot rotate. Electrolytic capacitor, characterized by being fixed to .

The sealing plate has a cylindrical portion protruding from the center of the inner surface, and a plurality of axial fitting grooves are formed on the inner peripheral surface of the cylindrical portion to form a fitting wall surface. A fitting tube portion provided on the outer surface of the fitting step portion is formed at the end, the fitting tube portion is fitted into the fitting wall surface, and the tube member projects coaxially to the inner surface side of the sealing plate. The electrolytic capacitor according to claim 1, wherein the electrolytic capacitor is fixed.

The meshing structure is provided so as to protrude from the inner surface side of the sealing plate and has a cylindrical member formed intermittently with a plurality of rectangular protruding engaging portions adjacent to each other at the tip, and one end opened to the bottom surface of the protruding engaging portion. The electrolytic capacitor according to claim 1, wherein the electrolytic capacitor is configured with a metal case in which a protruding engaging portion engaging groove is formed.

The meshing structure is provided so as to protrude from the inner surface side of the sealing plate, and a cylindrical member having a plurality of rectangular projecting engaging portions formed adjacent to each other at the tip, and one end opened and provided at the tip of the tube member. 2. A metal case in which a concave portion in which a plurality of protruding engaging portion engaging grooves engaging with a plurality of protruding engaging portions is formed in the inner peripheral surface is formed in the center of the bottom surface. The electrolytic capacitor as described.

The meshing structure is provided so as to protrude from the inner surface side of the sealing plate, and a cylindrical member having a plurality of rectangular projecting engaging portions formed adjacent to each other at the tip, and one end opened and provided at the tip of the tube member. 2. A metal case in which a plurality of projecting engaging portion engaging grooves engaging with a plurality of projecting engaging portions are formed on the outer peripheral surface, and a metal case in which a projecting portion is formed at the center of the bottom surface. The electrolytic capacitor as described.

The meshing structure is provided so as to protrude from the inner surface side of the sealing plate, and a cylindrical member having a plurality of rectangular projecting engaging portions formed adjacent to each other at the tip, and one end opened and provided at the tip of the tube member. 2. The electrolytic process according to claim 1, wherein the plurality of projecting engagement portion engaging grooves engaging with the plurality of projecting engaging portions are formed of a metal case formed on the upper surface of the bottom surface in a direction intersecting with the shaft. Capacitor.