546673 A7 B7 五、發明説明（1 ) 發明所屬之技術領域 (請先閱讀背面之注意事項再填寫本頁) 本發明係關於以自動斷路器、漏電斷路器等爲對象之 斷路器，詳細而言係有關於針對於該斷路器本體之殼體蓋 板上所劃成之附屬開關收納用之凹所的輔助蓋板之安裝構 習知技術 首先，以前述之自動斷路器爲例，成爲本發明之實施 對象的斷路器之構造係如第4圖、第5圖所示。於各圖面 中，1係爲由殼體2及蓋板3所組成之樹脂成形品的斷路 器殼體，4係爲與電源側端子爲一體成形之固定接觸子， 5係爲可動接觸子，6係爲開關機構，7係爲操作桿，8 係爲過載電流解扣裝置，9係爲負荷側端子，於前述蓋板 3上，使作爲附屬裝置（附加零件）之如後所述的附屬開 關並列於左右再收納的口袋形凹所3 a被劃成，且於該凹 所3 a上，設置了作爲開關蓋之輔助蓋板1 〇。 經濟部智慧財產局員工消費合作社印製 於此，斷路器殼體1之蓋板3，係使其中央部呈凸狀 膨起之形狀，並從該中央凸部的上面拉出操作桿7，而前 述之凹所3 a係鄰接於中央凸部，並被劃分於電源端子側 之領域上。又，輔助蓋板1 0，係使其左右兩端鉸鏈結合 於蓋板3之軸承部而呈外開式開關蓋，其蓋部係如圖面所 示一般，剖面爲L字形狀，並在緊挨著蓋板3之凸部壁面 的關閉位置，將其起立側之端面螺釘鎖緊於蓋板3上。 又，於第5圖中，1 1係爲作爲附屬開關之輔助開關 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -4 - 546673 A7 B7 五、發明説明（2 ) (請先閲讀背面之注意事項再填寫本頁) (連動於斷路器之可動接觸子5上’並使主電路接點的 〇N、〇F F狀態成爲電子信號後取出至外部），1 2係 爲警報開關（使斷路器之解扣動作成爲電子信號後取出至 外部），1 3係爲從開關1 1、1 2拉出，並與外部信號 線連接在一起之導線，於將此等附屬開關安裝於斷路器本 體之情況下，在使前述之輔助蓋板1 〇開啓於第4圖中之 虛線位置時，如第5圖所示一般’使輔助開關1 1、警報 開關1 2並列於左右後再插入安裝於斷路器殼體1之蓋板 3上所劃成之凹所3 a中。又，各附屬開關之導線1 3， 係從斷路器殼體1之側方拉出後再原封不動地連接至外部 信號線、或是將與導線1 3相互連接之專用的附屬端子座 (未圖示）安裝於斷路器殼體之側面上，於該附屬端子座 內與外部的信號線相連接。 發明欲解決之課題 經濟部智慧財產局員工消費合作社印製 於將前述斷路器安裝於使用處之分電盤、控制盤等之 情況下，從盤的前方執行操作桿操作地，使電源側之端子 朝上、負荷側端子朝下，並使斷路器呈縱向姿勢安裝於舖 設在盤內的支撐軌上。 在於這樣的使用處之分電盤上安裝斷路器之狀態，使 用者係於斷路器上追加安裝輔助開關1 1、警報開關1 2 等之附屬裝置的情況下，作爲其作業步驟，首先將輔助蓋 板1 0之制動螺釘旋鬆後，並將手搭在輔助蓋板上，打開 至開啓位置，於該狀態下，將附屬開關由前方插入安裝於 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -5- 546673 A7 B7 五、發明説明（3 ) 蓋板之凹所3 a上。 (請先閱讀背面之注意事項再填寫本頁) 然而，如前記所述地鉸鏈結合於斷路器1之蓋板3上 而呈外伸式之可自由開關之輔助蓋板1 0，係在朝上方彈 起的開啓位置，當手放開時，藉由自身重量而回到關閉位 置。爲此，在斷路器之使用處的現場，安裝、或是卸除附 屬裝置之情況下，作業者係必須一邊利用一隻手將輔助蓋 板1 0支撐於開啓位置，一邊利用另外一隻手進行輔助開 關等的安裝，因而會使這樣的作業形成難以進行的問題。 本發明係爲有鑑於上述之情況者，其目的係爲提供在 安裝斷路器於分電盤等之狀態，考量了使用者在安裝附屬 裝置的情況之作業性後，在輔助蓋板由關閉位置至開啓位 置的時候，即使將手放開依然可以原封不動地保持在開啓 位置地來加以改良其安裝構造之斷路器。 爲解決課題之手段 經濟部智慧財產局員工消費合作社印製 爲了達成上述目的，根據本發明的話，針對安裝了開關機 構之斷路器殼體的蓋板，並於該蓋板上，設置了使附屬開 關並列於左右再收納之凹所、及以鉸鏈結合於蓋板上而形 成外開式開關蓋之凹所的輔助蓋板之斷路器， 前述輔助蓋板係使由其左右兩端朝後方突出之臂鉸鏈 結合於蓋板上而呈外開式開關蓋，且在使輔助蓋板由關閉 位置至開啓位置的時候，具備了使輔助蓋板暫停於直立姿 勢之卡止保持手段（申請專利範圍第i項），而作爲該具 體的形恶’係爲於輔助蓋板之後緣上形成卡合段差部的同 本紙張尺度適用中國國家標準（CNS )八4規格（210><297公羞） -6 - 546673 A7 B7 五、發明説明（4 ) (請先閱讀背面之注意事項再填寫本頁) 時，且對向於該卡合段差部，並於斷路器之蓋板側上設置 卡合突起’在輔助盍板之開啓位置，使前述卡合段差部抵 接到卡合突起而可以使輔助蓋板暫停保持於直立姿勢地加 以構成（申請專利範圍第2項）。 根據上述構造的話，在使斷路器以縱向姿勢安裝於使 用處之分電盤等之狀態下，使用者係於安裝或是卸除輔助 開關、警報開關等之附屬裝置之情況時，當從斷路器之前 方，將手搭在輔助蓋板上後，由關閉位置打開至開啓位置 (水平姿勢）之時，輔助蓋板之卡合段差部係掛鉤於被設 置在斷路器蓋板上之卡合突起而暫停保持於該位置。藉此 ，於將手由輔助蓋板放開之情況下，可以使用兩隻手來進 行附屬開關之插入拆卸作業。 發明之實施形熊 以下，根據如第1圖〜第3圖所示之實施例加以說明 本發明之實施形態。又，於以實施例之圖面中對應第4圖 、第5圖之構件上附加相同的符號而省略其說明。 經濟部智慧財產局員工消費合作社印製 換言之，於圖面實施例中，斷路器之蓋板3、及附設 在劃成於該蓋板之附屬開關收納用之凹所3 a上的輔助蓋 板1 0之構造，基本上，雖然與第4圖、第5圖所示之習 知構造相同，但是就使輔助蓋板1 〇在開啓位置暫停於直 立姿勢之卡合保持手段而言，於蓋板3及輔助蓋板1 〇上 使如後所述之形狀部被追加形成。又，於第1 ( a )圖、 第1 ( b )圖中，3 b係爲軸支輔助蓋板1 〇之鉸鏈部（ 本紙張尺度適用中國國家標準（CNS ) Μ規格（21〇><297公釐） 546673 A7 _B7 五、發明説明（5 ) (請先閲讀背面之注意事項再填寫本頁) 軸承孔）、3 c係爲使輔助蓋板1 〇鎖緊於關閉位置之螺 釘孔，3 d係爲拉出操作桿7 (參考第4圖）之窗孔。又 ，1 0 a係爲由輔助蓋板之左右兩端朝後方突出之偏移臂 ，1 0 b係形成於前述臂1 〇 a之內面，並嵌合於蓋板3 之鉸鏈部3 b之支軸（圓形突起），1 〇 c係爲對應於前 述的螺釘孔3 c，並貫穿輔助蓋板1 〇之鎖緊螺釘的貫穿 又’作爲_述之卡止保持手段，於蓋板3上，係在對 應於斷路器殼體之相間隔壁之隔板部的頂部端面上形成如 第2 ( a )圖之放大圖面所示之卡合突起3 d的同時，且 對向於該卡合突起3 d，並於輔助蓋板1 〇上，係在蓋板 之後緣部上形成如第2 ( b )圖之放大圖面所示之卡合段 差部（凹部）1 0 d，且以鉸鏈部作爲支點，使隨著輔助 蓋板之開關動作的卡合段差部1 〇 d之移動軌跡與蓋板3 之卡合突起交叉結合般地設定著。 關於以上的構造，在安裝輔助蓋板1 〇於斷路器殼體 之蓋板3上之狀態下，當由第1 ( b )圖的關閉位置（實 經濟部智慧財產局員工消費合作社印製 線）朝開啓位置（虛線）開啓之時，在其移動的途中，輔 助蓋板1 0之後緣係接觸到卡合突起3 d，並啓動制動器 後’接著使卡合段差部（凹所）嵌入於卡合突起後而停止 ’輔助蓋板1 0係被卡止保持於該開啓位置。最後，在該 狀態下即使將手由輔助蓋板1 〇放開，亦會被保持於如第 1 ( b )圖之虛線所示之站立姿勢。 因此，如第5圖所述，在安裝於分電盤等之狀態，於 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -8 - 546673 A7 B7 五、發明説明（6 ) (請先閲讀背面之注意事項再填寫本頁) 斷路器上安裝輔助開關1 1、警報開關1 2等之附屬開關 的情況下，作爲其作業順序，係將輔助蓋板1 0卡合保持 於開啓位置後，可以自由地使用兩隻手來安裝附屬開關於 蓋板3之凹所3 a內，因而提升作業性。又，在安裝了附 屬開關之後，當利用指尖將被暫停保持於開啓位置之輔助 蓋板1 0朝關閉位置押下之時，使前述的卡合突起3 d與 卡合段差部1 0 d之卡合脫落後，輔助蓋板1 〇係藉由自 身重量倒下而回至關閉位置。 又，如第5圖所示，於安裝連接在附屬開關之導線 1 3的附屬端子座於斷路器殻體之側面的情況下，如第1 (a )圖所示一般，於蓋板3之左右側壁面的前後位置形 成燕尾槽3 f ，若使附屬端子座之卡合突起（燕尾榫）插 入於該燕尾槽3 f而加以安裝的話，即使於如前述之開啓 輔助蓋板1 0之狀態下，亦可以不妨礙到輔助蓋板地安裝 附屬端子座於斷路器殻體1之側面上。 發明之效果 經濟部智慧財產局員工消費合作社印製 如以上所述一般，根據本發明的話，針對由安裝了開 關機構之殼體及蓋板所組成之斷路器殼體，並於前述蓋板 上設置了使作爲附屬裝置的附屬開關並列於左右再收納之 附有輔助蓋板的凹所，且前述輔助蓋板係使其左右兩端朝 後方突出之臂鉸鏈結合於蓋板上而形成外開式開關蓋之斷 路器’在前述輔助蓋板由關閉位置至開啓位置的時候，設 置了使輔助蓋板暫停於直立姿勢之卡合保持手段，且作爲 本紙張尺度適用中國國家標隼（CNS ) A4規格（210X 297公羡） 546673 A7 B7 五、發明説明（7 ) (請先閱讀背面之注意事項再填寫本頁) 該卡合保持手段，係於蓋板3之後緣上形成卡合段差部的 同時，且對向於該卡合段差部，並於蓋板側上設置卡合突 起，藉由在輔助蓋板之開啓位置，使前述卡合段差部抵接 到卡合突起而使輔助蓋板暫停保持於直立姿勢的構造，在 安裝斷路器於分電盤等之狀態，於使用者追加安裝輔助開 關、警報開關等之附屬裝置的情況下，使輔助蓋板由關閉 位置開啓暫停於開啓位置，於該狀態下，可以自由地使用 兩隻手來安裝附屬開關，圖得其作業性的改善。 圖面簡單說明 第1圖係爲根據本發明之實施例之斷路器殼體蓋板的 構造圖，（a )係顯示拆下輔助蓋板之狀態的正面圖，（ b )係顯示（a )圖中之由箭頭方向所看到之X — X剖面 圖。 第2圖係顯示第1 ( b )圖中之主要部的部分擴大圖 ，（a )係顯示形成於蓋板側之卡合突起，（b )係顯示 形成於輔助蓋板之卡合段差部之形狀圖。 經濟部智慧財產局S工消費合作社印製 第3圖係顯示對應於第2圖之輔助蓋板的暫停動作說 明圖，（a ) 、（ b )係各自顯示輔助蓋板之關閉、開啓 之狀態圖。 第4圖係顯示安裝了本發明之附屬開關的斷路器之構 造剖面圖。 第5圖係顯示與附屬開關一起展現之第4圖之斷路器 的部分平面圖。 本紙張尺度適用中國國家標準（CNS ) A4規格（210X 297公釐） -10- 546673 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明説明（8 ) 符號說明 1 斷 路 器 2 殼 骨扭 3 蓋 板 3 a 凹 所 3 b 鉸 鏈 部 3 d 卡 合 突 起 1 〇 輔 助 蓋 板 1 0 a 臂 1 0 d 卡 合 段 差部 (請先閱讀背面之注意事項再填寫本頁) 、11 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） -11 -546673 A7 B7 V. Description of the invention (1) The technical field to which the invention belongs (please read the precautions on the back before filling out this page) The invention relates to circuit breakers for automatic circuit breakers, earth leakage circuit breakers, etc., in detail It is related to the mounting structure of the auxiliary cover for the auxiliary switch storage recess formed on the cover plate of the circuit breaker body. First, the aforementioned automatic circuit breaker is taken as an example to form the present invention. The structure of the circuit breaker to be implemented is shown in FIG. 4 and FIG. 5. In each drawing, 1 is a circuit breaker case of a resin molded product composed of a housing 2 and a cover plate 3, 4 is a fixed contact formed integrally with a power-side terminal, and 5 is a movable contact. 6 is the switch mechanism, 7 is the operating lever, 8 is the overload current trip device, 9 is the load-side terminal, and the cover 3 is used as an auxiliary device (additional part) as described below. The auxiliary switches are arranged in parallel to the pocket-shaped recesses 3 a which are accommodated in left and right, and an auxiliary cover plate 10 as a switch cover is provided on the recesses 3 a. Printed here by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the cover plate 3 of the circuit breaker housing 1 has a convex shape at its central portion, and the operating lever 7 is pulled out from the upper portion of the central convex portion. The aforesaid recess 3a is adjacent to the central convex portion, and is divided into the area on the power terminal side. In addition, the auxiliary cover plate 10 is hinged to the bearing portion of the cover plate 3 to form an open-type switch cover. The cover portion is generally as shown in the figure, the cross section is L-shaped, and Immediately next to the closed position of the wall surface of the convex portion of the cover plate 3, the end face screw of the rising side is fastened to the cover plate 3. Also, in Figure 5, 11 is an auxiliary switch as an auxiliary switch. The paper size applies the Chinese National Standard (CNS) A4 (210X297 mm) -4-546673 A7 B7 V. Description of the invention (2) (please Read the precautions on the back before filling in this page) (Linked to the movable contactor 5 of the circuit breaker and make the 0N and 0FF states of the main circuit contacts electronic signals and take them out to the outside), 1 2 is an alarm Switch (make the circuit breaker's tripping action become an electronic signal and then take it to the outside), 1 3 is a wire that is pulled out from the switches 1 1 and 12 and connected with the external signal wire. These auxiliary switches are installed In the case of the circuit breaker body, when the aforementioned auxiliary cover plate 10 is opened at the dotted line position in FIG. 4, as shown in FIG. 5, the auxiliary switch 1 1 and the alarm switch 12 are placed side by side. It is then inserted into the recess 3 a formed on the cover 3 of the circuit breaker housing 1. In addition, the wires 1 3 of each auxiliary switch are pulled out from the side of the circuit breaker housing 1 and then connected to the external signal line intact, or a dedicated auxiliary terminal base (not connected to the wire 1 3) (Illustrated) is installed on the side of the circuit breaker housing, and is connected to external signal wires in the auxiliary terminal block. The problem to be solved by the invention is printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. When the aforementioned circuit breaker is installed at the distribution board, control panel, etc. where the breaker is used, the operation lever is operated from the front of the panel to make the power supply side The terminals are facing up and the load-side terminals are facing down, and the circuit breaker is installed in a vertical posture on a support rail laid in the panel. In the state where a circuit breaker is installed on such a distribution board, when a user attaches auxiliary devices such as auxiliary switches 1 1 and alarm switches 12 to the circuit breaker, as an operation step, the auxiliary After loosening the brake screw of the cover 10, put your hand on the auxiliary cover and open it to the open position. In this state, insert the auxiliary switch from the front and install it on this paper. The Chinese standard (CNS) A4 applies. Specifications (210X297 mm) -5- 546673 A7 B7 V. Description of the invention (3) On the recess 3a of the cover. (Please read the precautions on the back before filling in this page) However, as mentioned above, the ground hinge is connected to the cover 3 of the circuit breaker 1 and the auxiliary cover 10, which can be extended freely, is extended. The open position popped up, when the hand is released, returns to the closed position by its own weight. For this reason, when installing or removing auxiliary equipment at the site where the circuit breaker is used, the operator must use one hand to support the auxiliary cover 10 in the open position, and use the other hand. Installation of an auxiliary switch or the like makes such work difficult to perform. The present invention has been made in view of the above circumstances, and its purpose is to provide a state in which a circuit breaker is installed on a power distribution board, etc., and after considering the workability of the user when installing an accessory device, the auxiliary cover is closed from the closed position. When it is in the open position, even if you release your hand, you can keep it in the open position to improve its circuit breaker. In order to solve the problem, printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. In order to achieve the above-mentioned object, according to the present invention, a cover plate of a circuit breaker housing in which a switch mechanism is installed is provided on the cover plate. The switches are juxtaposed in the left and right re-entrant recesses, and the circuit breaker is an auxiliary cover plate that is hinged to the cover plate to form an open switch cover recess. The auxiliary cover plate is protruded rearward from its left and right ends. The arm hinge is combined with the cover to form an open-type switch cover, and when the auxiliary cover is moved from the closed position to the open position, it is provided with a locking and holding means to suspend the auxiliary cover in an upright position (Scope of patent application) Item i), and the specific form of evil is that the same paper size that forms the difference of the engaging section on the trailing edge of the auxiliary cover plate applies the Chinese National Standard (CNS) 8-4 specification (210 > < 297) ) -6-546673 A7 B7 V. Description of the invention (4) (Please read the precautions on the back before filling this page), and face the difference of the engaging section, and set a card on the cover side of the circuit breaker Close Since 'in the open position of the auxiliary plate He, so that the engaging stepped portion abuts against the engagement projection and the auxiliary plate can be held suspended in the upright posture be added to form (Patent Application range item 2). According to the above structure, in a state where the circuit breaker is installed in a vertical position on a distribution board or the like at the place of use, when the user is installing or removing auxiliary devices such as auxiliary switches and alarm switches, In front of the device, when you place your hand on the auxiliary cover and open it from the closed position to the open position (horizontal posture), the difference in the engaging section of the auxiliary cover is hooked to the engagement provided on the cover of the circuit breaker. Protrude and stay in this position. With this, when the hand is released from the auxiliary cover, two hands can be used to insert and remove the auxiliary switch. Embodiments of the Invention Embodiments of the present invention will be described below with reference to the embodiments shown in Figs. 1 to 3. In addition, the components corresponding to FIG. 4 and FIG. 5 in the drawings of the embodiment are given the same reference numerals, and descriptions thereof are omitted. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economics In other words, in the illustrated embodiment, the cover plate 3 of the circuit breaker and the auxiliary cover plate attached to the recess 3 a for the storage of the auxiliary switch formed on the cover plate The structure of 10 is basically the same as the conventional structure shown in Figs. 4 and 5. However, in terms of the engaging and retaining means for holding the auxiliary cover 10 in the upright position in the open position, the cover The plate 3 and the auxiliary cover plate 10 are formed with additional shape portions as described later. Moreover, in Fig. 1 (a) and Fig. 1 (b), 3b is the hinge part of the shaft support auxiliary cover 10 (this paper size applies the Chinese National Standard (CNS) M specification (21〇 > < 297 mm) 546673 A7 _B7 V. Description of the invention (5) (Please read the precautions on the back before filling in this page) Bearing holes), 3 c are screws for locking the auxiliary cover 1 〇 in the closed position Hole, 3 d is the window hole for pulling out the operation lever 7 (refer to Figure 4). In addition, 10 a is an offset arm protruding from the left and right ends of the auxiliary cover plate toward the rear, and 10 b is formed on the inner surface of the arm 10 a and is fitted to the hinge portion 3 b of the cover 3 The support shaft (round protrusion), 10c, corresponds to the aforementioned screw hole 3c, and penetrates through the locking screw of the auxiliary cover plate 10, and is used as the locking and retaining means described in the cover plate. 3, is formed on the top end surface of the partition portion corresponding to the partition wall of the circuit breaker casing as shown in the enlarged view of FIG. 2 (a), and is opposed to the The engaging protrusion 3 d is formed on the auxiliary cover plate 10 at the rear edge portion of the cover plate, as shown in the enlarged view of Fig. 2 (b), the engaging step difference (recess) 10 d, and With the hinge portion as a fulcrum, the movement trajectory of the engaging section difference portion 10d following the opening and closing operation of the auxiliary cover plate and the engaging protrusion of the cover plate 3 are set in a crosswise combination. Regarding the above structure, when the auxiliary cover plate 10 is installed on the cover plate 3 of the circuit breaker housing, when the closed position shown in FIG. 1 (b) is printed (the line printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Real Economy) ) When it is opened toward the open position (dotted line), during its movement, the rear edge of the auxiliary cover 10 contacts the engaging protrusion 3 d, and after the brake is activated, the engaging section difference (recess) is then embedded in After the protrusion is engaged, it stops. The auxiliary cover 10 is locked and held in the open position. Finally, even if the hand is released from the auxiliary cover 10 in this state, it will be held in a standing position as shown by the dashed line in FIG. 1 (b). Therefore, as shown in Figure 5, in the state of being installed on a distribution board, etc., the Chinese National Standard (CNS) A4 specification (210X297 mm) is applied to this paper standard. -8-546673 A7 B7 V. Description of the invention (6) (Please read the precautions on the back before filling this page.) When auxiliary switches 1 1 and alarm switches 12 are installed on the circuit breaker, the auxiliary cover 10 is engaged and maintained as the operation sequence. After the open position, the auxiliary switch can be freely installed in the recess 3 a of the cover plate 3 with two hands, thereby improving workability. In addition, after the auxiliary switch is installed, when the auxiliary cover 10 temporarily held in the open position is pushed down by the fingertip toward the closed position, the engagement protrusion 3 d and the engagement section difference 10 d are caused. After the engagement is released, the auxiliary cover 10 is returned to the closed position by falling down by its own weight. In addition, as shown in FIG. 5, when the auxiliary terminal seat connected to the wire 13 of the auxiliary switch is installed on the side of the circuit breaker housing, as shown in FIG. 1 (a), Dovetail grooves 3 f are formed at the front and rear positions of the left and right side wall surfaces. If the engaging protrusions (dovetails) of the auxiliary terminal block are inserted into the dovetail groove 3 f and installed, the auxiliary cover 10 is opened even as described above. The auxiliary terminal seat can also be installed on the side of the circuit breaker housing 1 without hindering the auxiliary cover. The effect of the invention is printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs as described above. According to the present invention, a circuit breaker housing composed of a housing and a cover plate equipped with a switch mechanism is printed on the cover plate. A recess with an auxiliary cover plate is arranged in parallel to the left and right to be accommodated as an auxiliary device, and the auxiliary cover plate is such that the arm hinges of which the left and right ends protrude rearwardly are connected to the cover plate to form an outer opening. When the auxiliary cover is switched from the closed position to the open position, the circuit breaker of the switch cover is provided with an engaging and holding means for suspending the auxiliary cover in an upright position, and the Chinese national standard (CNS) is applied as the paper standard A4 specification (210X 297 public envy) 546673 A7 B7 V. Description of the invention (7) (Please read the precautions on the back before filling this page) This retaining means is formed on the back edge of the cover 3 to form the difference in the engaging section At the same time, it is opposite to the engaging section difference, and an engaging protrusion is provided on the side of the cover plate, so that the foregoing engaging section difference portion is abutted against the engaging protrusion by the auxiliary cover opening position. The auxiliary cover is temporarily held in an upright position. When the circuit breaker is installed in a power distribution panel, etc., and the user adds auxiliary devices such as auxiliary switches and alarm switches, the auxiliary cover is moved from the closed position. The opening is paused in the open position. In this state, the auxiliary switch can be freely installed with two hands, and the workability is improved. Brief description of the drawings The first figure is a structural view of a circuit breaker case cover according to an embodiment of the present invention, (a) is a front view showing a state in which an auxiliary cover is removed, and (b) is (a) X-X sectional view seen from the direction of the arrow in the figure. Fig. 2 is an enlarged view showing a part of the main part in Fig. 1 (b), (a) is an engagement protrusion formed on the cover side, and (b) is an engagement step difference formed on the auxiliary cover. Shape illustration. Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs, S Industrial Consumption Cooperative, Figure 3 shows the pause operation of the auxiliary cover corresponding to Figure 2, (a) and (b) show the closed and opened states of the auxiliary cover Illustration. Fig. 4 is a sectional view showing the construction of a circuit breaker to which the accessory switch of the present invention is installed. Fig. 5 is a partial plan view showing the circuit breaker of Fig. 4 shown together with the accessory switch. This paper size applies to Chinese National Standard (CNS) A4 specification (210X 297 mm) -10- 546673 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of the invention (8) Symbol description 1 Circuit breaker 2 Torsional shell bone 3 Cover 3 a Recess 3 b Hinge 3 d Engagement protrusion 1 〇 Auxiliary cover 1 0 a Arm 1 0 d Engagement difference (please read the precautions on the back before filling this page), 11 Paper size Applicable to China National Standard (CNS) A4 specification (210X297 mm) -11-