JPH03114117A - Circuit breaker - Google Patents

Abstract

PURPOSE:To lessen the number of parts of a circuit breaker and provide a circuit breaker having good braking property at low cost by forming an insulating piece, which prevents arcing between a fixed contactor and a movable contactor, unitedly with a diaphragm. CONSTITUTION:A diaphragm 14 installed between a switching system to switch a movable contactor 5 and an arc extinguishing chamber 10 is composed with an insulating material such as polyester, PET, melamine resin, etc., and it has an undercut 14b to step over a moving line 14a of the movable contactor 5 and the fixed contactor 3 in the right and left center. The tip parts 14c of both leg parts are inserted into grooves of a lower case 1 and both shoulders 14d are pushed by the tip parts of side walls of the arc extinguishing chamber 10 so as to fix the diaphragm. An insulating piece 15 projected forward and horizontally in the upper periphery of the undercut 14b is formed unitedly with the diaphragm 14. This insulating piece 15 covers upper plane of the fixed contactor 3 and thus prevents arcing between the fixed contactor and the movable contactor 5.

Description

【発明の詳細な説明】[Detailed description of the invention] 【産業上の利用分野】[Industrial application field]

この発明は、配線用遮断器などの小型の回路遮断器に関
し、更に詳しくはその遮断性能を高めるための手段に関
する。The present invention relates to a small circuit breaker such as a molded case circuit breaker, and more particularly to means for improving its breaking performance.

【従来の技術】[Conventional technology]

小型で高遮断容量の回路遮断器を実現するためには、遮
断時に発生するアークを如何に急速に消滅させるかが重
要で、従来より種々の工夫が行われている。一方、短絡
遮断時における金属溶融物が開閉機構に付着して動作不
良を生じさせることを防止するために、消弧室と開閉機
構との間に絶縁物の隔壁を設けたものがある。 第７図はそのような従来の回路遮断器の前半部（電源側
）のみを示すもので、第７図（Ａ）は−半のみ上部カバ
ーを取り去った投入状態における平面図、第７図（Ｂ）
はそのＢ−Ｂ線に沿う断面図である。図において、■は
下部ケース、２は上部カバー　３は下部ケース１に固定
された固定接触子、４はその先端に接合された固定接点
、５はホルダ６を介して下部ケース１に回動可能に支持
された可動接触子、７はその先端に固定接点４と対向し
て接合された可動接点、８は可動接触子５を開閉動作さ
せる開閉機構、９はその操作ハンドル、１０は固定接触
子３及び可動接触子５を囲んで配置された消弧室である
。 固定接触子３は固定接点４の支持端部が上方にＵ字状に
折り返されて、可動接触子５と互いに異なる方向に電流
が流れる平行導体部３ａを形成し、その反対側の基端部
は電源側端子３ｂとなっている。また、消弧室１０は多
段に積み重ねられた鉄板製のグリッド１０ａと、これを
保持する絶縁物の側壁１０ｂとからなり、グリッド１０
ａには可動接触子５の移動軌跡に沿って７字状の切欠が
設けられている。 ここで、操作ハンドル９を図の右方向に操作すると、開
閉機構８の動作により可動接触子５は急速開離する。ま
た、過負荷電流あるいは短絡電流が流れると、図示しな
い過電流用外し装置が動作して同様に可動接触子５が開
離する。可動接触子５の開離時に固定接点４と可動接点
７との間にアークが発生するが、このアークは固定接触
子３及び可動接触子５を流れる電流からの電磁力により
図の左方向に駆動され、更に固定接触子３に固定された
アークホーン１１に導かれてグリッド、１０ａに引き込
まれる。その結果、アークはグリッド１０ａにより冷却
されるとともに、短いアークに分割されてアーク電圧が
高められ２、速に消滅する。 このような遮断過程において、短絡電流などの大電流遮
断時には、アークの足が接点４．７からはみ出し、接触
子３．５にまで拡がる。そこで、図示の場合は固定接触
子３側に絶縁テープ１２を巻き、接触子３．５間の発弧
を防いでいる。また、短絡電流遮断などの場合に、接点
４，７や接触子３．５の一部が溶融して飛散し、開閉機
構８に付着しないように、消弧室ＩＯと開閉機構８との
間に絶縁物の隔壁１３が設けられている。 第８図は上記隔壁１３を示す正面図である。図示の通り
、隔壁１３は左右の中心に可動接触子５の移動通路１３
ａ及び固定接触子３を跨ぐための逃げ溝１３ｂが切り欠
かれた逆Ｕ字状で、両脚部先端１３ｃが下部ケース１の
図示しない溝に差し込まれ、両肩１３ｄが消弧室１０の
側壁１０ｂの先端で押さえられて第８図に示すように保
持される。 ところで、アークの消滅を促す手段としては、上記！！
縁テープ１２の他に種々のものが提案されている。まず
、特公昭６３−３７４５３号公報あるいは実開昭６２−
９３４０号公報には、固定接触子あるいは可動接触子の
接点の外周を取り囲むように圧力反射板を配置してアー
クの足を絞り込み、アーク電圧を高めて限流性能を向上
しようとしたものが記載されている。また、特開昭６２
−２０８５２２号公報には、消弧室グリッドの凹部内の
両側面に絶縁物を配置し、アークを絞り込んで消弧性能
を高めようとしたものが記載されている。更に、特開昭
６４−７７８１１号公報には、アークに曝される位置に
高分子絶縁材料の絶縁体を設け、アークにより絶縁体が
熱分解されて発生する水素ガスでアークを冷却して消弧
しようとしたものが記載されている。In order to realize a circuit breaker that is small and has a high breaking capacity, it is important to quickly extinguish the arc that occurs when the circuit is broken, and various efforts have been made to date. On the other hand, in order to prevent molten metal from adhering to the opening/closing mechanism during short-circuit breakage and causing malfunction, some devices have an insulating partition between the arc extinguishing chamber and the opening/closing mechanism. Figure 7 shows only the front half (power supply side) of such a conventional circuit breaker, and Figure 7 (A) is a plan view of the negative half in the closed state with the top cover removed. B)
is a sectional view taken along the line BB. In the figure, ■ is the lower case, 2 is the upper cover, 3 is the fixed contact fixed to the lower case 1, 4 is the fixed contact joined to its tip, and 5 is rotatable to the lower case 1 via the holder 6. 7 is a movable contact joined to the tip of the movable contact facing the fixed contact 4; 8 is an opening/closing mechanism for opening and closing the movable contact 5; 9 is an operating handle thereof; 10 is a fixed contact 3 and a movable contactor 5. In the fixed contact 3, the supporting end of the fixed contact 4 is folded upward into a U-shape to form a parallel conductor part 3a through which current flows in different directions from the movable contact 5, and the base end on the opposite side is the power supply side terminal 3b. Further, the arc extinguishing chamber 10 is composed of a grid 10a made of iron plates stacked in multiple stages and an insulating side wall 10b that holds the grid.
A is provided with a 7-shaped notch along the locus of movement of the movable contact 5. Here, when the operating handle 9 is operated to the right in the figure, the movable contact 5 is rapidly opened and closed by the operation of the opening/closing mechanism 8. Further, when an overload current or a short circuit current flows, an overcurrent disconnection device (not shown) operates and the movable contact 5 similarly opens. When the movable contact 5 is opened, an arc is generated between the fixed contact 4 and the movable contact 7, but this arc is caused by the electromagnetic force from the current flowing through the fixed contact 3 and the movable contact 5 to the left in the figure. It is driven, further guided by the arc horn 11 fixed to the fixed contact 3, and drawn into the grid 10a. As a result, the arc is cooled by the grid 10a, divided into short arcs, the arc voltage is increased, and the arc is quickly extinguished. In such a breaking process, when a large current such as a short circuit current is cut off, the legs of the arc protrude from the contact 4.7 and spread to the contact 3.5. Therefore, in the illustrated case, an insulating tape 12 is wrapped around the fixed contact 3 to prevent arcing between the contacts 3 and 5. In addition, in order to prevent the contacts 4, 7 and the contacts 3.5 from melting and scattering and adhering to the opening/closing mechanism 8 in the event of short-circuit current interruption, etc. A partition wall 13 made of an insulating material is provided at. FIG. 8 is a front view showing the partition wall 13. As shown in the figure, the partition wall 13 has a movement passage 13 for the movable contact 5 at the center of the left and right sides.
It has an inverted U-shape with an escape groove 13b cut out for straddling the fixed contact 3, and the tips 13c of both legs are inserted into grooves (not shown) in the lower case 1, and the shoulders 13d are connected to the side wall of the arc extinguishing chamber 10. It is held by the tip of 10b as shown in FIG. By the way, as a means to encourage the disappearance of the arc, the above is the method! !
Various other tapes besides edge tape 12 have been proposed. First of all, please refer to Japanese Patent Publication No. 63-37453 or Utility Model Application Publication No. 62-
Publication No. 9340 describes an attempt to improve current limiting performance by arranging a pressure reflection plate to surround the outer periphery of the contact of a fixed or movable contact to narrow down the legs of the arc and increase the arc voltage. has been done. Also, JP-A-62
Japanese Patent No. 208522 describes an arrangement in which an insulator is placed on both sides of the concave portion of an arc extinguishing chamber grid to narrow down the arc and improve arc extinguishing performance. Furthermore, JP-A-64-77811 discloses that an insulator made of a polymeric insulating material is provided at a position exposed to the arc, and the arc is cooled and extinguished with hydrogen gas generated when the insulator is thermally decomposed by the arc. What you tried to do is described.

【発明が解決しようとする課題】[Problem to be solved by the invention]

ところが、これらの従来の回路遮断器では、アークの絞
り込みや冷却を図るために、圧力反射板や絶縁物を別途
必要とし、その分部品点数が増えてコストアップや組立
工数の増加を招くという問題があった。 この発明は、別部品を設けない簡単な構成で遮断性能を
高めるようにした回路遮断器を提供することを目的とす
るものである。However, these conventional circuit breakers require separate pressure reflectors and insulators to narrow down the arc and cool it, which increases the number of parts, leading to increased costs and assembly man-hours. was there. An object of the present invention is to provide a circuit breaker that has a simple configuration that does not require separate parts and has improved interrupting performance.

【課題を解決するための手段】[Means to solve the problem]

上記目的を達成するために、この発明は、接点を介して
互いに接離する固定接触子及び可動接触子を囲んで消弧
室が配置され、前記可動接触子を開閉動作させる開閉機
構と前記消弧室との間に絶縁物の隔壁が設けられた回路
遮断器において、固定接触子の可動接触子との対向面を
覆う絶縁片を隔壁と一体に形成するものである。In order to achieve the above object, the present invention provides an arc extinguishing chamber in which an arc extinguishing chamber is arranged surrounding a fixed contact and a movable contact that come into contact with and separate from each other via contacts, and an opening/closing mechanism that opens and closes the movable contact and the extinguisher. In a circuit breaker in which an insulating partition wall is provided between an arc chamber and an arc chamber, an insulating piece that covers a surface of a fixed contact facing a movable contact is formed integrally with the partition wall.

【作　用】[For use]

固定接触子と可動接触子との間の発弧を防ぐ絶縁片を隔
壁と一体に形成するので部品点数が減る。Since the insulating piece that prevents arcing between the fixed contact and the movable contact is formed integrally with the partition wall, the number of parts is reduced.

【実施例】【Example】

それでは図に基づいてこの発明の詳細な説明する。ここ
で、第１図は回路遮断器の要部縦断面図、第２図〜第６
図は隔壁のそれぞれ異なる実施例のいずれも（Ａ）は平
面図、（Ｂ）は側面図、（Ｃ）は正面図である。なお、
以下の各実施例において互いに対応する部分には同一の
符号を付けるものとし、また従来例と同一部分には同一
の符号を付けて説明を省略する。 まず、第２図において、隔壁１４はポリエステル、ＰＥ
Ｔ、メラニン樹脂などの絶縁物からなり、その形状は第
８図の従来例と実質的に同じで、左右の中心に可動接触
子５の移動通路１４ａ及び固定接触子３を跨ぐための逃
げ溝１４ｂが切り欠かれており、両脚部先端１４ｃが下
部ケース１の図示しない溝に差し込まれ、両肩１４ｄが
消弧室１０の側壁ｔａｂの先端で押さえられて固定され
る。 この隔壁１４には、逃げ溝１４ｂの上縁部に前方に水平
に突出する絶縁片１５が一体形成されている。この絶縁
片１５は第２図（Ｂ）に２点鎖線で示したように固定接
触子３の上面を覆い、図示しない可動接触子との間の発
弧を防いでいる。これにより、第７図に示したような絶
縁テープ１２が不要となる。また、絶縁片１５は隔壁１
４と一体のため、従来のように位置ずれして固定接点４
の上に乗り上げるという心配がない。 第３図は上記隔壁１４の固定をより強固にするための実
施例で、下部ケース１の溝に差し込まれていた脚部１４
ｃの先端が削除され、逃げ溝１４ｂの左右の縁に沿って
隔壁１４及び絶縁片１５と一体に一対の側壁１６が設け
られている。そして、側壁１６の内側には、鋸歯状断面
の爪１６ａが対向するように形成されている。この隔壁
１４は固定接触子３に上方から押し込まれ、爪１６ａが
スナツプフィツト式に固定接触子３の平行導体部３ａの
下面に係合することにより固定される。この固定は脚部
１４ｃの先端が下部ケース１に差し込まれる方法に比べ
て特に前後方向の倒れが少なくより強固である。 第４図は第３図の隔壁１４に固定接触子３の０曲部３ｃ
（第１図）を覆うカバー１７を一体形成した実施例で、
これにより、Ｕ曲部３Ｃに短絡遮断時の金属溶融物が付
着して相間絶縁が低下することが防止される。 第５図は第４図の隔壁１４に、可動接触子５の移動通路
１４ａを挟む一対の側壁１日が一体形成された実施例を
示すものである。この側壁１８は短絡電流遮断時にアー
クを絞り込んでアーク電圧を高め、同時にアークに曝さ
れて水素ガスを発生してアークを冷却する。 最後に、第６図は第５図における絶縁片１５が固定接点
４の外周を取り囲むよう延長された実施例を示すもので
ある。これにより、アークの足が固定接点４の外側に拡
がらず、アークの絞り込み効果が一層向上する。 第１図は第６図の隔壁１４が装着された回路遮断器を示
す要部縦断面図である。図示構成によれば、絶縁片１５
や側壁１８が隔壁１４と一体に設けられるため、これら
の絶縁体が別に設けられるものに比べて部品点数が減り
、その分、部品コストが低下し、組立工数が少なくなる
。The present invention will now be described in detail based on the drawings. Here, FIG. 1 is a vertical cross-sectional view of the main parts of the circuit breaker, and FIGS.
In the figures, (A) is a plan view, (B) is a side view, and (C) is a front view of each of the different embodiments of the partition wall. In addition,
In each of the following embodiments, parts that correspond to each other are given the same reference numerals, and parts that are the same as those in the conventional example are given the same reference numerals, and a description thereof will be omitted. First, in FIG. 2, the partition wall 14 is made of polyester or PE.
T, made of an insulating material such as melanin resin, and its shape is substantially the same as that of the conventional example shown in FIG. 14b is cut out, the tips 14c of both legs are inserted into grooves (not shown) of the lower case 1, and the shoulders 14d are pressed and fixed by the tips of the side walls tab of the arc extinguishing chamber 10. This partition wall 14 is integrally formed with an insulating piece 15 that projects horizontally forward at the upper edge of the relief groove 14b. This insulating piece 15 covers the upper surface of the fixed contact 3, as shown by the two-dot chain line in FIG. 2(B), and prevents arcing between it and the movable contact (not shown). This eliminates the need for the insulating tape 12 as shown in FIG. Further, the insulating piece 15 is connected to the partition wall 1
Because it is integrated with 4, the fixed contact 4 may be misaligned as in the conventional case.
You don't have to worry about it running over you. FIG. 3 shows an embodiment for more firmly fixing the partition wall 14, in which the legs 14 inserted into the grooves of the lower case 1
The tip of the groove 14b is removed, and a pair of side walls 16 are provided integrally with the partition wall 14 and the insulating piece 15 along the left and right edges of the relief groove 14b. On the inside of the side wall 16, claws 16a having a serrated cross section are formed to face each other. The partition wall 14 is pushed into the fixed contact 3 from above, and is fixed by the claws 16a engaging with the lower surface of the parallel conductor portion 3a of the fixed contact 3 in a snap fit manner. Compared to the method in which the tips of the leg portions 14c are inserted into the lower case 1, this fixing is more stable, with less tilting particularly in the front-back direction. FIG. 4 shows the 0-bend portion 3c of the fixed contact 3 on the partition wall 14 in FIG.
(Fig. 1) is an embodiment in which a cover 17 is integrally formed to cover the
This prevents molten metal from adhering to the U-bent portion 3C during short-circuit interruption and reducing interphase insulation. FIG. 5 shows an embodiment in which a pair of side walls sandwiching a moving path 14a of the movable contact 5 are integrally formed with the partition wall 14 of FIG. 4. This side wall 18 constricts the arc and increases the arc voltage when the short circuit current is interrupted, and at the same time is exposed to the arc and generates hydrogen gas to cool the arc. Finally, FIG. 6 shows an embodiment in which the insulating piece 15 in FIG. 5 is extended to surround the outer periphery of the fixed contact 4. In FIG. This prevents the legs of the arc from spreading outside the fixed contact 4, further improving the arc narrowing effect. FIG. 1 is a vertical sectional view of a main part of a circuit breaker to which the partition wall 14 of FIG. 6 is attached. According to the illustrated configuration, the insulating piece 15
Since the side wall 18 and the partition wall 14 are provided integrally with the partition wall 14, the number of parts is reduced compared to a case where these insulators are provided separately, and the cost of parts is reduced accordingly, and the number of assembly steps is reduced.

【発明の効果】【Effect of the invention】

この発明によれば、固定接触子を覆う絶縁片が隔壁と一
体構成されるため、部品点数が減るとともに組立工数が
少なくなり、遮断性能の優れた回路遮断器を安価に供給
できるようになる。According to this invention, since the insulating piece that covers the fixed contact is integrally formed with the partition wall, the number of parts and assembly steps are reduced, and a circuit breaker with excellent breaking performance can be provided at a low cost.

【図面の簡単な説明】[Brief explanation of drawings]

第１図はこの発明の実施例の要部縦断面図、第２図（Ａ
）は隔壁の第１の実施例の平面図、第２図（Ｂ）はその
側面図、第２図（Ｃ）はその正面図、第３図（Ａ）は同
じく第２の実施例の平面図、第３図（Ｂ）はその側面図
、第３図（Ｃ）はその正面図、第４図（Ａ）は同じく第
３の実施例の平面図、第４図（Ｂ）はその側面図、第４
図（Ｃ）はその正面図、第５図（Ａ）は同じく第４の実
施例の平面図、第５図（Ｂ）はその側面図、第５図（Ｃ
）はその正面図、第６図（Ａ）は同じく第５の実施例の
平面図、第６図（Ｂ）はその側面図、第６図（Ｃ）はそ
の正面図、第７図（Ａ）は従来例の要部平面図、第７図
（Ｂ）はそのＢ−Ｂ線に沿う断面図、第８図は第７図に
おける隔壁の正面図である。 ３・・・固定接触子、４・・・固定接点、５・・・可動
接触子、７・・・可動接点、８・・・開閉機構、１０・
・・消弧室、１４・・・隔壁、１５・・・絶縁片。 第 ３ 図 第 図 １ （Ａ） （Ｂ） 第 図 第 図 （Ｃ） １ム ｌ−のFIG. 1 is a vertical sectional view of the main part of an embodiment of the invention, and FIG. 2 (A
) is a plan view of the first embodiment of the partition wall, FIG. 2(B) is a side view thereof, FIG. 2(C) is a front view thereof, and FIG. 3(A) is a plan view of the second embodiment. 3(B) is a side view thereof, FIG. 3(C) is a front view thereof, FIG. 4(A) is a plan view of the third embodiment, and FIG. 4(B) is a side view thereof. Figure, 4th
FIG. 5(C) is a front view of the fourth embodiment, FIG. 5(A) is a plan view of the fourth embodiment, FIG. 5(B) is a side view thereof, and FIG.
) is its front view, FIG. 6(A) is a plan view of the fifth embodiment, FIG. 6(B) is its side view, FIG. 6(C) is its front view, and FIG. 7(A) is its front view. ) is a plan view of the main part of the conventional example, FIG. 7(B) is a sectional view taken along the line B-B, and FIG. 8 is a front view of the partition wall in FIG. 7. 3... Fixed contact, 4... Fixed contact, 5... Movable contact, 7... Movable contact, 8... Opening/closing mechanism, 10.
... Arc extinguishing chamber, 14 ... Partition wall, 15 ... Insulating piece. Figure 3 Figure 1 (A) (B) Figure Figure 1 (C) 1ml-

Claims (1)

【特許請求の範囲】[Claims] １）接点を介して互いに接離する固定接触子及び可動接
触子を囲んで消弧室が配置され、前記可動接触子を開閉
動作させる開閉機構と前記消弧室との間に絶縁物の隔壁
が設けられた回路遮断器において、固定接触子の可動接
触子との対向面を覆う絶縁片を隔壁と一体に形成したこ
とを特徴とする回路遮断器。1) An arc extinguishing chamber is disposed surrounding a fixed contact and a movable contact that come into contact with and separate from each other via contacts, and an insulating partition is provided between the opening/closing mechanism that opens and closes the movable contact and the arc extinguishing chamber. What is claimed is: 1. A circuit breaker comprising: an insulating piece that covers a surface of a fixed contact facing a movable contact and is integrally formed with a partition wall.