JPH064508Y2 - Movable contact support lock device for electromagnetic contactor - Google Patents

Description

【考案の詳細な説明】 〔産業上の利用分野〕 この考案は電磁接触器に取外し可能に付属する消弧室ケ
ースの取外し時に接触子開離状態で拘束する可動接触子
支えロック装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a movable contactor support locking device for restraining an arc extinguishing chamber case detachably attached to an electromagnetic contactor in a contact-separated state at the time of removal.

〔従来の技術〕[Conventional technology]

電磁接触器で消弧室ケースの取外し可能なものとしては
第９図ないし第１３図ならびに第１４図ないし第１６図
にそれぞれ示す異なる二例が知られている。まず第９図
ないし第１３図において、電磁接触器は本体ケース１上
に配置された接触子装置２０と、接触子装置に連結され
本体ケース１内に収納され接触子装置２０を開閉操作す
る電磁石３０と、接触子装置２０にかぶせられ本体ケー
ス１に着脱自在に取付けられた消弧室ケース２とで主要
部が構成されている。接触子装置２０は本体ケース１上
に間隔をおき対向するように配置され、対向側に固定接
点１１，１１を有し反対側に端子１２，１２が延長され
た固定接触子１３，１３と、固定接触子１３，１３の対
向間を上下方向摺動自在に案内された可動接触子支え１
４の上端に支持され固定接点１１，１１間を橋絡，解放
する可動接触子１５と、可動接触子１５に接触圧力を付
与する接触ばね１６とを主な構成要素として備えてい
る。電磁石３０は本体ケース１の底部に固定された固定
鉄心２１と、固定鉄心２１に巻装された励磁コイル２２
と、固定鉄心２１と対向配置され接触子装置２０の可動
接触子支え１４に連結された可動鉄心２３と、可動接触
子支え１４と本体ケース１との間に弾装された復帰ばね
２４とを主な構成要素として備えている。本体ケースの
幅方向の両側耳部１ａ，１ａには、片側のみしか図示さ
れていないが、消弧室ケース２との接合面から貫通し本
体ケース１の両側壁に沿う長孔１ｂと、耳部１ａ，１ａ
の背面側に設けられ長孔１ｂと直交する細溝１ｃとが設
けられている。消弧室ケース２にはその両側に片側のみ
しか図示されていないが、本体ケース１の長孔１ｂと一
致する上側の大径部２ａと、接合面側の小径部２ｂとで
なる取付孔２ｃが設けられている。一方本体ケース１と
消弧室ケース２とは固定軸３とコイルばね４によって結
合され、固定軸３は頭部３ａと軸部３ｂとでなり、頭部
３ａの頂部には溝３ｃが設けられ、軸部３ｂの先端には
溝３ｃの方向に沿うピン５が貫通固着されている。そし
て結合はコイルばね４が巻装された固定軸３をピン５が
長孔１ｂに一致するようにして取付孔２ｃに挿入し、ピ
ン５が長孔１ｂをくぐったことを確認してねじ回しで90
゜捻回してピン５を細溝１ｃに係合させ、ねじ回しによ
る押圧を解除するとコイルばね４のばね力により固定さ
れる。すなわちワンタッチ操作に近い固定軸３の取付孔
２ｃへの挿入と、ねじ回しによる固定軸をコイルばね４
に拡して押圧そして90゜の捻回という簡単な操作で固定
される。As the electromagnetic contactor with which the arc-extinguishing chamber case can be detached, two different examples shown in FIGS. 9 to 13 and 14 to 16 are known. First, in FIG. 9 to FIG. 13, an electromagnetic contactor is a contactor device 20 arranged on the body case 1, and an electromagnet connected to the contactor device and housed in the body case 1 to open and close the contactor device 20. 30 and an arc-extinguishing chamber case 2 which is attached to the main body case 1 so as to be covered with the contactor device 20 and detachable from the main body case 1. The contact device 20 is arranged on the main body case 1 so as to be opposed to each other with a space therebetween, and fixed contacts 13 and 13 having fixed contacts 11 and 11 on opposite sides and terminals 12 and 12 extended to opposite sides. Movable contact support 1 guided vertically slidably between opposed fixed contacts 13, 13.
The movable contactor 15 supported on the upper end of the bridge 4 for bridging and releasing the fixed contacts 11, 11 and the contact spring 16 for applying a contact pressure to the movable contactor 15 are provided as main components. The electromagnet 30 includes a fixed iron core 21 fixed to the bottom of the main body case 1 and an exciting coil 22 wound around the fixed iron core 21.
A movable iron core 23 arranged to face the fixed iron core 21 and connected to the movable contactor support 14 of the contactor device 20, and a return spring 24 elastically mounted between the movable contactor support 14 and the main body case 1. It is provided as a main component. Although only one side is illustrated in both side ears 1a, 1a in the width direction of the main body case, a long hole 1b penetrating from a joint surface with the arc extinguishing chamber case 2 and extending along both side walls of the main body case 1, and an ear. Part 1a, 1a
A slot 1c provided on the back side of the slot and a narrow groove 1c orthogonal to the slot 1b are provided. Although only one side is shown on both sides of the arc-extinguishing chamber case 2, a mounting hole 2c composed of an upper large-diameter portion 2a corresponding to the elongated hole 1b of the main body case 1 and a small-diameter portion 2b on the joining surface side. Is provided. On the other hand, the main body case 1 and the arc extinguishing chamber case 2 are connected by a fixed shaft 3 and a coil spring 4, the fixed shaft 3 is composed of a head 3a and a shaft portion 3b, and a groove 3c is provided on the top of the head 3a. A pin 5 is fixed through the tip of the shaft portion 3b along the direction of the groove 3c. Then, the coupling is performed by inserting the fixed shaft 3 around which the coil spring 4 is wound into the mounting hole 2c so that the pin 5 is aligned with the elongated hole 1b, and confirming that the pin 5 has passed through the elongated hole 1b. At 90
When the pin 5 is engaged with the narrow groove 1c by being twisted by a degree and the pressing by the screwdriver is released, the pin 5 is fixed by the spring force of the coil spring 4. That is, inserting the fixed shaft 3 into the mounting hole 2c, which is similar to one-touch operation, and attaching the fixed shaft by screwdriver to the coil spring 4
It is fixed by a simple operation of spreading and pressing and twisting 90 degrees.

次に第１４図ないし第１６図においてこの例の前述の例
との相違する点は固定軸６が異なるのみで、固定軸６の
軸部６ｂの先端が、頭部６ａの溝６ｃの方向への折曲げ
で係止部６ｄが形成されていることである。したがって
その機能ならびに結合操作は前述の例と同様である。Next, in FIGS. 14 to 16, the only difference between this example and the above-mentioned example is the fixed shaft 6, and the tip of the shaft portion 6b of the fixed shaft 6 is directed toward the groove 6c of the head portion 6a. That is, the locking portion 6d is formed by bending. Therefore, the function and the combining operation are the same as in the above-mentioned example.

〔考案が解決しようとする課題〕[Problems to be solved by the device]

このような従来装置においては、消弧室ケース２を取外
した場合は第１０図に示す状態になる。すなわち保守点
検などでもし消弧室ケース２を外し、誤って励磁コイル
２２の制御回路電源の開閉が行なわれると、接触子装置
２０は遮断能力を持たないで電路を開閉することにな
る。その結果遮断不能や相間短絡などを起こし、その事
故は電磁接触器のみにとどまらず、電路に接続された機
器などのその他にまで波及することがあるという問題点
があった。In such a conventional apparatus, when the arc extinguishing chamber case 2 is removed, the state shown in FIG. 10 is obtained. That is, if the arc extinguishing chamber case 2 is removed and the control circuit power supply for the exciting coil 22 is opened / closed by mistake for maintenance or the like, the contact device 20 does not have a breaking capability and opens / closes the electric circuit. As a result, there is a problem in that the circuit cannot be interrupted or a phase-to-phase short circuit occurs, and the accident is not limited to the electromagnetic contactor and may spread to other devices such as devices connected to the electric circuit.

この考案の目的は前述した従来の問題点を除去し、消弧
室ケースを外した状態では誤まっての励磁コイル制御電
源の開閉が行なわれるようなことがあっても接触子装置
の開閉が行なわれることのない電磁接触器の可動接触子
支えロック装置を提供することにある。The object of the present invention is to eliminate the above-mentioned conventional problems and to open / close the contact device even if the exciting coil control power supply is opened / closed by mistake when the arc extinguishing chamber case is removed. It is an object of the present invention to provide a movable contactor support locking device for an electromagnetic contactor that is not operated.

〔課題を解決するための手段〕[Means for Solving the Problems]

この考案は前述の目的を達成するために、消弧室ケース
の幅方向の両側に設けられ壁面に沿う大径部と小径部と
からなる取付孔と、該取付孔と連通する長孔および係合
孔が接合面に設けられるとともに長孔および係合孔と交
差し側壁から内壁に貫通する案内孔が設けられた本体ケ
ースと、該本体ケース内に上下方向摺動自在に案内され
接触子開離状態で前記案内孔と一致する少なくとも一側
の凹所が設けられた可動接触子支えと、前記取付孔およ
び長孔を頂部に溝を有する頭部とコイルばねを介して貫
通し先端に前記案内孔の頂辺と係合する係止部が設けら
れた固定軸と、前記案内孔の少なくとも一側に進退自在
に案内され前記係合孔に前記消弧室ケースの取付け状態
で弾性的に係合する舌片，前記固定軸の係止部と係合し
消弧室ケースの取外しにともなう捻回で前記凹所に嵌入
するロック片でなるロック駒とを備えたことである。In order to achieve the above-mentioned object, the present invention has a mounting hole formed on both sides in the width direction of the arc-extinguishing chamber case and having a large diameter portion and a small diameter portion along the wall surface, and a long hole and an engaging hole communicating with the mounting hole. A main body case provided with a dowel hole on the joint surface and a guide hole that intersects the long hole and the engagement hole and penetrates from the side wall to the inner wall, and the contactor is slidably guided in the main body case in the vertical direction. A movable contactor support provided with a recess on at least one side corresponding to the guide hole in a separated state, a head having a groove at the top through the mounting hole and the elongated hole, and a coil spring through the head, A fixed shaft provided with a locking portion that engages with the top side of the guide hole, and is elastically guided in at least one side of the guide hole so as to elastically elastically move into the engagement hole when the arc-extinguishing chamber case is attached. The tongue that engages, the engaging part of the fixed shaft that engages the arc extinguishing chamber case It is provided with a lock piece which in twisting times due to teeth made of a lock piece that fits into the recess.

〔作用〕[Action]

この考案による可動接触子支えロック装置においては、
消弧室ケースを本体ケースに取付ける固定軸の係止部
に、固定軸の消弧室ケース取外し方向への捻回操作に係
合して可動接触子支えの凹所に嵌入するロック駒を本体
ケースに設けるとともに、ロック駒に位置保持機能を持
たせたことにより、消弧室ケースを外せば接触子装置は
開離状態でロックされる。したがって保守点検時の事故
が回避されるとともに安全が確保される。また消弧室ケ
ースの装着が容易となる。In the movable contact support lock device according to the present invention,
Attaching the arc-extinguishing chamber case to the main body case A lock piece that engages with the twisting operation of the fixed shaft in the arc-extinguishing chamber case removal direction and fits into the recess of the movable contact support is attached to the main body. Since the lock piece is provided in the case and the lock piece has the function of holding the position, the contact device is locked in the open state by removing the arc extinguishing chamber case. Therefore, accidents during maintenance and inspection are avoided and safety is secured. Also, the arc extinguishing chamber case can be easily mounted.

〔実施例〕〔Example〕

第１図ないし第６図はこの考案による電磁接触器の可動
接触子支えロック装置の一実施例を示す図で、第１図は
一部縦断面を示す側面図、第２図は消弧室ケースを外し
た斜視図、第３図はロック解除状態の要部拡大縦断面
図、第４図は第３図のIII−III線に沿う断面図、第５図
はロック状態の第４図に対応する横断面図、第６図は要
部部品の斜視図である。図において前述した第９図の従
来装置と同一部分には同一符号を付すことで対応させ相
違点について説明する。この実施例において従来装置と
相違する点の概略は、消弧室ケース２を本体ケース１に
取付ける固定軸３の係止ピン５に、固定軸３の消弧室ケ
ース取外し方向の捻回操作に係合して可動接触子支え１
４に設けられた凹所１４ａに嵌入して可動接触子支え１
４を接触子装置２０の開離状態で拘束するロック駒３１
を本体ケース１に設けたことである。そのために本体ケ
ース１には、両側耳部１ａの片側のみしか図示されてい
ない長孔１ｂの近傍に位置する係合孔１ｄと、長孔１ｂ
および係合孔１ｄと交差して外壁から内壁に貫通する方
形状の案内孔１ｅとが設けられ、可動接触子支え１４に
は接触子装置２０が開離状態で一致する前述の凹所１ａ
が設けられている。この凹所１４ａは両側に設けられる
のが最善だが片側のみでもよい。そして案内孔１ｅには
第６図に示すロック駒３１が進退可能に案内され、ロッ
ク駒３１は凹所１４ａに嵌入可能なロック片３１ａと、
固定軸３のピン５が嵌入して90゜の捻回が可能となるＬ
字状の貫通孔３１ｂと、貫通孔３１ｂのＬ字状の内側に
位置し案内孔１ｅの差込口に向い弾性を持って切り起こ
された係合孔１ｄと係合可能な舌片３１ｃとを備えてい
る。1 to 6 are views showing an embodiment of a movable contact supporting lock device for an electromagnetic contactor according to the present invention. FIG. 1 is a side view showing a partial longitudinal section, and FIG. 2 is an arc extinguishing chamber. FIG. 3 is a perspective view with the case removed, FIG. 3 is an enlarged vertical sectional view of an essential part in an unlocked state, FIG. 4 is a sectional view taken along the line III-III in FIG. 3, and FIG. 5 is FIG. 4 in a locked state. The corresponding cross-sectional view, FIG. 6 is a perspective view of essential parts. In the figure, the same parts as those of the conventional device of FIG. In this embodiment, the points different from the conventional device are outlined in that the locking pin 5 of the fixed shaft 3 for mounting the arc-extinguishing chamber case 2 on the main body case 1 is twisted in the removing direction of the arc-extinguishing chamber case of the fixed shaft 3. Engagement and movable contact support 1
4 is fitted in a recess 14a provided in the movable contact support 1
4 is a lock piece 31 for restraining 4 in the opened state of the contactor device 20.
Is provided in the main body case 1. Therefore, in the main body case 1, an engaging hole 1d located near a long hole 1b, which is shown only on one side of the both ear portions 1a, and a long hole 1b.
And a rectangular guide hole 1e that intersects with the engagement hole 1d and penetrates from the outer wall to the inner wall, and the movable contactor support 14 has the above-mentioned recess 1a with which the contactor device 20 is in the open state.
Is provided. The recess 14a is best provided on both sides, but it may be on only one side. A lock piece 31 shown in FIG. 6 is guided in the guide hole 1e so as to be able to move forward and backward, and the lock piece 31 includes a lock piece 31a which can be fitted into the recess 14a.
The pin 5 of the fixed shaft 3 fits in and can be twisted 90 °.
A through hole 31b having a V-shape, and a tongue piece 31c located inside the L-shape of the through hole 31b and elastically cut and raised toward the insertion port of the guide hole 1e and engageable with the engagement hole 1d. Is equipped with.

以上の構成において本体ケース１への消弧室ケース２の
取付けは、まず接触子装置２０の開離状態において本体
ケース１に消弧室ケース２を載せ、つぎにロック駒３１
を第５図に示すように案内孔１ｅにロック片３１ａが可
動接触子支え１４の凹所１４ａに嵌入するまでロック駒
３１を差し込みロック状態とする。このときロック駒３
１の舌片３１ｃに弾性を持たせてあるので、案内孔１ｅ
の頂辺に圧接されて抜け止めされ、そして固定軸３のピ
ン５は耳部１ａの長孔１ｂ内に位置する。つぎにねじ回
しで固定軸３の頭部３ａをコイルばね４に抗して押し込
み、第５図のＰ矢方向に捻回することで、ピン５の先端
がロック駒３１の貫通孔３１ｂの内壁に当たりロック駒
３１を右方向に移動し、ねじ回しによる押し込み力を解
除すればピン５が細溝１ｃと係合して位置決めされる。
そしてこのことにより可動接触子支え１４のロックが解
除されると同時に、消弧室ケース２が本体ケース１に固
定される。つぎに保守点検に際しての消弧室ケース２の
取外しは、前述の逆操作を行ないロック駒３１をロック
状態にしておけばよく、この状態で励磁コイル２２にそ
の制御回路電源の万一の開閉があっても、接触子装置２
０が開離状態でロックされているので、遮断不能や相間
短絡などの事故を起こすことはない。第７図および第８
図はいずれもロック駒３１の変形例であって、第７図の
ロック駒３２は摺動方向の両側に案突条３２ａ，３２ａ
が設けられた点で異なり、第８図のロック駒３３は耳部
１ａの細溝１ｃと係合する突条３３ａが設けられた点で
異なる。したがってロック駒３２は本体ケース１の耳部
１ａ肉厚が薄い場合に都合がよく、ロック駒３３は案内
孔１ｅ内を摺動しやすい利点がある。In the above structure, the arc extinguishing chamber case 2 is attached to the main body case 1 by first placing the arc extinguishing chamber case 2 on the main body case 1 with the contactor device 20 in the open state, and then by the lock piece 31.
As shown in FIG. 5, the lock piece 31a is inserted into the guide hole 1e until the lock piece 31a is fitted into the recess 14a of the movable contact support 14, and the lock piece 31 is locked. Lock piece 3 at this time
Since the tongue piece 31c of No. 1 has elasticity, the guide hole 1e
The pin 5 of the fixed shaft 3 is positioned in the long hole 1b of the ear 1a by being pressed against the top side of the pin to prevent the pin from coming off. Next, the head portion 3a of the fixed shaft 3 is pushed in by a screwdriver against the coil spring 4 and twisted in the direction of arrow P in FIG. 5, so that the tip of the pin 5 is the inner wall of the through hole 31b of the lock piece 31. When the lock piece 31 is moved to the right and the pushing force by the screwdriver is released, the pin 5 is engaged with the narrow groove 1c and positioned.
As a result, the movable contact support 14 is unlocked, and at the same time, the arc extinguishing chamber case 2 is fixed to the main body case 1. Next, in order to remove the arc-extinguishing chamber case 2 for maintenance and inspection, it is sufficient to perform the above-mentioned reverse operation to bring the lock piece 31 into the locked state. Contact device 2
Since 0 is locked in the open state, accidents such as inability to shut off and short-circuiting between phases will not occur. 7 and 8
Each of the figures is a modification of the lock piece 31, and the lock piece 32 of FIG. 7 has a pair of projecting ridges 32a, 32a on both sides in the sliding direction.
8 is different from the lock piece 33 shown in FIG. 8 in that it has a protrusion 33a that engages with the narrow groove 1c of the ear 1a. Therefore, the lock piece 32 is convenient when the wall thickness of the ear portion 1a of the main body case 1 is thin, and the lock piece 33 has an advantage that it can easily slide in the guide hole 1e.

〔考案の効果〕[Effect of device]

この考案によれば消弧室ケースを本体ケースに取付ける
固定軸の係止部を利用し、接触子装置開離状態の可動接
触子支えに設けられた凹所に嵌入可能にして本体ケース
に位置決め案内されたロック駒を消弧室ケースの取外し
にともなう固定軸の捻回操作で凹所に嵌入させるように
したことにより、消弧室ケースの着脱の作業性を損ねる
ことなく組込易く確実にして信頼性の高い電磁接触器の
可動接触子支えロック装置を提供することができる。According to this invention, by utilizing the locking portion of the fixed shaft that attaches the arc-extinguishing chamber case to the main body case, it can be fitted into the recess provided in the movable contactor support in the contactor device opened state and positioned in the main body case. The guided lock piece is inserted into the recess by twisting the fixed shaft that accompanies the removal of the arc-extinguishing chamber case, making it easy to assemble and secure without damaging the workability of attaching and detaching the arc-extinguishing chamber case. It is possible to provide a movable contactor support locking device for an electromagnetic contactor that is highly reliable.

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

第１図ないし第６図はこの考案による電磁接触器の可動
接触子支えロック装置の一実施例を示す図で、第１図は
一部縦断面を示す側面図、第２図は消弧室ケースを外し
た斜視図、第３図はロック解除状態の要部拡大縦断面
図、第４図は第３図のIII−III線に沿う断面図、第５図
はロック状態の第４図に対応する横断面図、第６図は要
部部品の斜視図、第７図および第８図はそれぞれ第６図
の変形例を示す斜視図、第９図ないし第１３図は従来の
電磁接触器の一例を示す図で、第９図は一部縦断面を示
す側面図、第１０図は消弧室ケースを外した斜視図、第
１１図は要部拡大平面図、第１２図は第１１図の縦断面
図、第１３図は第１２図の背面図、第１４図ないし第１
６図は従来の電磁接触器の他の例を示す図で、第１４図
は要部平面図、第１５図は第１４図の縦断面図、第１６
図は第１５図の背面図である。 １……本体ケース、１ｂ……長孔、１ｄ……案内孔、１
ｅ……案内孔、２……消弧室ケース、２ａ……大径部、
２ｂ……小径部、２ｃ……取付孔、３……固定軸、３ａ
……頭部、３ｃ……溝、５……ピン、１４……可動接触
子支え、１４ａ……凹所、２０……接触子装置、３１，
３２，３３……ロック駒、３１ａ……ロック辺、３１ｃ
……舌辺。1 to 6 are views showing an embodiment of a movable contact supporting lock device for an electromagnetic contactor according to the present invention. FIG. 1 is a side view showing a partial longitudinal section, and FIG. 2 is an arc extinguishing chamber. FIG. 3 is a perspective view with the case removed, FIG. 3 is an enlarged vertical sectional view of an essential part in an unlocked state, FIG. 4 is a sectional view taken along the line III-III in FIG. 3, and FIG. 5 is FIG. 4 in a locked state. Corresponding cross-sectional views, FIG. 6 is a perspective view of essential parts, FIGS. 7 and 8 are perspective views showing modified examples of FIG. 6, and FIGS. 9 to 13 are conventional electromagnetic contactors. FIG. 9 is a side view showing a partial vertical cross section, FIG. 10 is a perspective view with an arc extinguishing chamber case removed, FIG. 11 is an enlarged plan view of an essential part, and FIG. FIG. 13 is a vertical sectional view, FIG. 13 is a rear view of FIG. 12, and FIGS.
FIG. 6 is a view showing another example of a conventional electromagnetic contactor, FIG. 14 is a plan view of a main part, FIG. 15 is a vertical sectional view of FIG. 14, and FIG.
The figure is a rear view of FIG. 1 ... Main body case, 1b ... Long hole, 1d ... Guide hole, 1
e ... Guide hole, 2 ... Arc extinguishing chamber case, 2a ... Large diameter part,
2b ... small diameter part, 2c ... mounting hole, 3 ... fixed shaft, 3a
...... Head, 3c ...... groove, 5 ...... pin, 14 ...... movable contact support, 14a ...... recess, 20 ...... contact device, 31,
32, 33 ... Lock piece, 31a ... Lock side, 31c
...... Tongue.

Claims (1)

【実用新案登録請求の範囲】[Scope of utility model registration request] 【請求項１】消弧室ケースの幅方向の両側に設けられ壁
面に沿う大径部と小径部とからなる取付孔と、概取付孔
と連通する長孔および係合孔が接合面に設けられるとと
もに長孔および係合孔と交差し側壁から内壁に貫通する
案内孔が設けられた本体ケースと、該本体ケース内に上
下方向摺動自在に案内され接触子開離状態で前記案内孔
と一致する少なくとも一側に凹所が設けられた可動接触
子支えと、前記取付孔および長孔を頂部に溝を有する頭
部とコイルばねを介して貫通し先端に前記案内孔の頂辺
と係合する係止部が設けられた固定軸と、前記案内孔の
少なくとも一側に進退自在に案内され前記係合孔に前記
消弧室ケースの取付け状態で弾性的に係合する舌片，前
記固定軸の係止部と係合し消弧室ケースの取外しにとも
なう捻回で前記凹所に嵌入するロック片でなるロック駒
とを備えてなることを特徴とする電磁接触器の可動接触
子支えロック装置。1. An attachment hole, which is provided on both sides in the width direction of an arc-extinguishing chamber case and has a large diameter portion and a small diameter portion along a wall surface, and a long hole and an engagement hole which communicate with the approximate attachment hole are provided on a joint surface. And a main body case provided with a guide hole that intersects the elongated hole and the engaging hole and penetrates from the side wall to the inner wall, and the guide hole in the main body case slidably guided in the vertical direction in the contact open state. A movable contactor support having a recess provided on at least one side that matches, a head having a groove at the top through the mounting hole and the elongated hole, and a coil spring that penetrates through the attachment hole and the elongated hole at the tip and engages with the top side of the guide hole. A fixed shaft provided with a locking portion to be fitted, a tongue piece which is guided forward and backward to at least one side of the guide hole and elastically engages with the engagement hole in a mounted state of the arc extinguishing chamber case, It engages with the locking part of the fixed shaft and twists when the arc extinguishing chamber case is removed. Electromagnetic contactor movable contact support lock device characterized by comprising a lock piece made of locking pieces fitted to.