KR101009386B1 - Circuit breaker - Google Patents

Abstract

In a circuit breaker comprising a main body case (2), a center cover (3), and an upper cover (4) arranged in such a way that they are divided from each other, the main body case (2) comprises a contactor section and an arc-extinguishing. device (9) and overcurrent tripping device (12), the center cover (3) is placed in the main body case (2) and has a recess (3a) in the center, which is partitioned by a bottom wall. Receiving the opening and closing mechanism 10 and the built-in accessories in the recess, the top cover 4 covers the upper surface of the recess 3a in the center cover 3, the center cover 3 is coupled to this center cover And an auxiliary cover 14 covering the opening / closing mechanism 10, and the upper cover 4 is mounted on the auxiliary cover 14. The secondary cover 14 covers an area other than the accommodating part of the built-in accessory, and the upper cover 4 is hingedly coupled to the end of the secondary cover.

Therefore, it is possible to improve the assembly structure of the molded case 1, thereby increasing the ease of assembly and the safety of the assembly work.

Description

Circuit breaker {CIRCUIT BREAKER}

1 is an exploded cross-sectional view showing a circuit breaker configuration according to Embodiment 1 of the present invention, before the auxiliary cover and the top cover are mounted;

FIG. 2 is a perspective view illustrating an open state of an upper cover after assembling the circuit breaker shown in FIG. 1; FIG.

3 is an exploded perspective view showing the circuit breaker configuration according to Embodiment 2 of the present invention with the top cover open and the auxiliary cover removed from the body case;

4 is an exploded cross-sectional view showing the configuration of a circuit breaker having a background structure.

<Explanation of symbols for the main parts of the drawings>

1: molded case 2: body case

3: center cover 3a: recess

4 top cover 7 movable contactor

9: extinguishing device 10: opening and closing mechanism

12: overcurrent trip device 13: video current transformer (leakage detecting unit)

14: auxiliary cover

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker including a circuit breaker or an earth leakage breaker, and more particularly, to an assembly structure of a molded case for accommodating a functional part of a breaker.

As is known, a wiring breaker is a contactor section each of which is assembled together inside a molded case, each comprising a fixed contactor and a movable contactor of the main circuit, and an arcing device for each contactor section. -extinguishing device, opening / closing mechanism for movable contactor, and overcurrent tripping device. In addition to the functional components constituting the circuit breaker, the leakage circuit breaker is composed of an electric leakage detecting unit (image current transformer and an electric leakage detecting circuit) and an overcurrent protection device additionally installed in the molded case (for example, Japanese Patent No. 3246562). Publication).

In the circuit breaker of the above-described configuration, an arc is generated between the fixed contact and the movable contact in the main circuit when the overcurrent such as the short circuit current is interrupted. Due to the heat of the arc, the metal of the contact material melts and evaporates. The evaporated molten metal is scattered with the arc gas to the surroundings and is deposited on the moving parts of the trip device and the opening and closing mechanism, causing a problem of lowering the blocking operation function. Therefore, as a countermeasure for preventing the above problem, the following configuration is known (see, for example, Japanese Patent Laid-Open No. 7-141976). In this configuration, the intermediate base is incorporated inside the molded case so that the current interrupting portion and the arc extinguishing device are isolated from the opening and closing mechanism disposed thereon by the intermediate base serving as the compartment wall.

In addition, a circuit breaker having the following configuration is also known. In this configuration, the pocket-shaped recess is preformed in the cover of the molded case so that attachments of circuit breakers such as auxiliary switches, alarm switches and voltage trip devices can be easily mounted. The accessory device is accommodated in the form of a cassette in the recess, and an auxiliary cover is provided on the case cover to cover the upper surface of the accessory device (see, for example, Japanese Patent Laid-Open No. 6-236726).

On the other hand, in addition to the configuration disclosed in Japanese Patent Laid-Open No. 7-141976, in which the intermediate base is incorporated in a molded case, a circuit breaker having the following assembly structure is already developed and commercially available. In this assembly structure, the molded case is itself configured to isolate the opening and closing mechanism from the current interruption portion, and may also contain a built-in accessory device such as the molded case disclosed in Japanese Patent Laid-Open No. 6-236726. . The molded case is divided into three parts: a main case (lower case), a central cover having an upper portion of the upper portion covering the upper surface of the concave portion of the central cover, and a central cover having a concave portion formed on the upper side of the main case and partitioned by a bottom wall. Has a structure. The contactor portion, arc extinguishing device and overcurrent trip device are accommodated in the main body case, and the opening and closing mechanism and the built-in accessory device are accommodated in the recessed portion of the center cover. Next, the assembly structure of the circuit breaker is shown in FIG.

In Fig. 4, reference numeral 1 denotes a molded case (resin molded article) having a structure that can be divided into three parts: a main body case (lower case) 2, a center cover 3, and an upper cover 4. Reference numerals 5 , 6 , 7 and 8 denote fixed contactors integral with the power supply terminal, and contactor holders for rotatably supporting the load side terminal, the movable contactor and the movable contactor 7, respectively. Reference numeral 9 denotes an arc extinguishing device. Reference numerals 10 , 10a, and 11 denote a toggle link type opening and closing mechanism, an opening and closing operation lever, and a tripping mechanism connected to the toggle link of the opening and closing mechanism 10, respectively. Reference numeral 12 denotes an overcurrent trip device for operating the trip mechanism 11 by detecting overcurrent in the main circuit, and reference numeral 13 denotes an image current transformer mounted on an earth leakage breaker for detecting a short circuit in the main circuit. In the video current transformer 13, a ground fault detection IC is connected to the secondary side to form a ground fault detection unit. Since the opening and closing operation and the current blocking operation of the circuit breaker are known, a description thereof will be omitted here.

Here, in the main body case 2 of the molded case 1, the units including the fixed contactor 5, the movable contactor 7 and the extinguishing device 9 corresponding to each phase of the main circuit are laterally oriented. Parallel to each other. An overcurrent trip device (thermal device) 12 is arranged between the load side terminals 6, and an image current transformer 13 is further disposed behind the unit.

Moreover, the center cover 3 arrange | positioned at the main body case 2 is equipped with the pocket-shaped recessed part 3a formed in the center part, and the wall for partitions is provided around this recessed part 3a. The recessed part 3a accommodates the opening-closing mechanism 10 and the tripping mechanism 11 in the center part, and the built-in attachment device (not shown), such as the overcurrent prevention device of the above-mentioned leakage circuit breaker, an auxiliary switch, an alarm switch, and a voltage trip device. Not to the side. In addition, the lower toggle link 10b of the opening / closing mechanism 10 is lowered through the slit opened in the bottom wall 3b of the recess 3a so as to be coupled to the contactor holder 8 of the movable contactor 7. Is formed to protrude.

In addition, the upper cover 4 is attached to the upper surface of the center cover 3 to cover the upper portion of the recess 3. The upper cover 4 has an opening formed at its central portion, and is formed such that the opening and closing operation lever 10a of the opening and closing mechanism 10 protrudes outward through the opening.

The above-described circuit breaker having a background structure has the following problems in view of ease of maintenance and assembly. That is, accessories of circuit breakers such as auxiliary switches, alarm switches and voltage trip devices are often mounted by the user after transporting the circuit breakers. In this case, the attachment and detachment of the accessory device are performed by approaching the recess 3a in the center cover 3 with the top cover 4 shown in FIG. 4 removed. In approach, a mistake such as accidental contact of the operator's fingertips with the tripping mechanism 11 in the opening / closing mechanism 10 results in an unexpected tripping action of the opening / closing mechanism, which causes the operator's finger to open / close the opening mechanism. You will be injured unexpectedly.

Moreover, in the assembly process of the leakage circuit breaker provided with the functional component which comprises the wiring circuit breaker assembled in the main body case 2, the video current transformer 13 (leakage detection part) is additionally attached. Furthermore, in the assembling process, not only the center cover 3 equipped with the opening / closing mechanism 10 and the overcurrent protection circuit is attached to the main body case 2, but also the lead wires drawn out from the ground fault detection unit are attached to the central cover 3. Connection to the overcurrent protection device is performed. Wiring work performed with the open / close mechanism 10 exposed may result in an unexpected tripping action of the open / close mechanism as described above, resulting in the risk of fingers being caught in the open / close mechanism.

In view of the above, the present invention has been devised for the purpose of improving the structure of a molded case based on the structure shown in Fig. 4 and improving the ease of assembly and maintenance.

In order to achieve the above object, according to the first aspect of the present invention, the circuit breaker includes a main body case, a center cover and an upper cover which are arranged to be divided into each other, and the main body case accommodates the contactor portion, the arc extinguishing device and the overcurrent trip device. The central cover is placed in the main body case and has a recess in the center part partitioned by the bottom wall to accommodate the opening and closing mechanism and the built-in accessory, the upper cover covers the upper surface of the recess in the central cover, and the central cover is subsidiary. It is formed to have a cover to cover the opening and closing mechanism coupled to the central cover, the auxiliary cover is configured to be mounted to the upper cover. The auxiliary cover is particularly formed in accordance with the second and third aspects of the invention described below.

(1) The auxiliary cover covers an area other than the built-in accessory receiving portion, and the upper cover is hinged to the end of the auxiliary cover (second aspect).

(2) The auxiliary cover is divided into a cover portion covering the opening and closing mechanism and a cover portion covering the circumferential surface area of the opening and closing mechanism, and the cover portion covering the opening and closing mechanism is attached to the main body case (third aspect).

In the above-described configuration, in the state where the upper cover of the circuit breaker is opened, the opening and closing mechanism is covered by the auxiliary cover. Thus, when the built-in accessory is mounted on or disconnected from the circuit breaker, it accesses the receiving area (concave) of the built-in accessory formed in the central cover so that there is no possibility of finger contact with the opening and closing mechanism, Mounting and dismounting can be performed. This improves the safety in maintenance work performed by the user.

Furthermore, the configuration according to the third aspect of the present invention divides the auxiliary cover into a cover portion covering the opening / closing mechanism and a cover portion covering the circumferential surface area of the opening / closing mechanism, and to mount the cover portion covering the opening / closing mechanism independently to the main body case. Is provided. By adopting this configuration, when additionally installing the earth leakage detector and the overcurrent protection device on the molded case including the functional parts of the circuit breaker already mounted in the earth leakage circuit breaker assembly process, the assembling work is opened and closed on the center cover. The mechanism is covered by a cover portion covering the opening and closing mechanism, and can be performed with the other cover portion separated. As a result, the mounting work for mounting the ground fault detecting unit to the main body case and the wiring work between the overcurrent protection device mounted on the center cover and the ground fault detecting unit can be safely performed without any possibility of contacting the opening and closing mechanism. Therefore, it is possible to ensure that the ease of assembly and the stability during assembly work are increased.

In the following, an embodiment of the present invention will be described based on the example shown in Figs. In the drawings of the embodiment, the same components as those shown in FIG. 4 are denoted by the same reference numerals, and description thereof is omitted.

Example 1

First of all, the circuit breaker according to the first embodiment is shown in Figs. 1 and 2 by taking an earth leakage breaker as an example of a circuit breaker. Example 1 corresponds to the first and second aspects of the invention. FIG. 1 shows that the functional parts shown in FIG. 4 are mounted on the central cover 3 and the main body case 2 of the molded case 1, and the upper cover 4 and the new auxiliary cover 14 additionally mounted are assembled before assembly. This is a cross-sectional view showing the separated state. 2 is a perspective view showing a state in which the top cover 4 is opened after assembling the circuit breaker. 1 and 2, the same components as those shown in FIG. 4 are denoted by the same reference numerals, and description thereof is omitted.

Here, the auxiliary cover 14 is an upper part of the built-in accessory device (auxiliary and alarm switch 16 and the voltage trip device 17) receiving portion (concave portion) formed in the central cover 3 as shown in FIG. The opening / closing mechanism 10 excluding the area, the bimetallic overcurrent trip device 12, which is aligned on the rear side of the open / close mechanism 10 and mounted on the main body case 2, the electromagnetic overcurrent trip device 15, , The upper region of the image current transformer (earth leakage detector) 13 is formed. The secondary cover 14 is mounted on the upper part of the central cover 3 with the upper cover 4 hinged on the rear end of the secondary cover 14 and screwed to the main body case 2, so that the upper cover 4 ) To allow the opening and closing of Reference numeral 18 denotes an overcurrent protection device connected to the ground fault detecting unit by a lead wire and mounted on the center cover 3.

In the above configuration, in the state where the top cover 4 is opened after assembling the circuit breaker, the opening and closing mechanism 10 is covered by the auxiliary cover 14 as shown in FIG. Thus, in this state, the access area of the built-in accessory device in the center cover 3 is accessed without any possible contact with the opening and closing mechanism, and the accessory device such as the auxiliary and alarm switch 16 and the voltage trip device 17 are provided. Mounting and dismounting can be performed safely.

Example 2

3 is an exploded view showing the configuration of the circuit breaker with the top cover 4 open and the auxiliary cover 14 separated from the main body case 2 according to Embodiment 2 corresponding to the third aspect of the present invention. Perspective view.

In the second embodiment, the auxiliary cover 14 described in the first embodiment is divided into a cover portion 14-1 and a cover portion 14-2 . The cover portion 14-1 is a dedicated cover portion covering only the opening / closing mechanism 10 mounted on the central cover 3. The cover portion 14-2 is mounted on the main body case 2 to cover the upper region of the functional parts such as the overcurrent trip device 12, 15 (see FIG. 1) and the image current transformer 13, and 10) is aligned behind. Here, the cover portion 14-1 is formed to have a box structure that is screwed independently from the top of the main body case 2 to cover the opening / closing mechanism 10 mounted on the central cover 3. The other cover portion 14-2 is hinged to the upper cover 4 on the rear end as in Embodiment 1 described above. Further, the left side of the cover extends forward to cover the upper portion of the overcurrent prevention device 18 provided on the side of the opening and closing mechanism 10.

The above-described dividable auxiliary cover 14 has the following effects in the assembly process of the earth leakage breaker. That is, in the assembling process before attaching the auxiliary cover 14 and the upper cover 4, at the stage where the mounting of the various functional parts of the circuit breaker to the center cover 3 is completed, it is dedicated to the opening / closing mechanism 10. Cover the cover portion 14-1 and screw it to the case body 2. In this state, the video current transformer 13 (leakage detecting unit) is additionally mounted on the main body case 2. In addition, with the overcurrent prevention device 18 mounted on the center cover 3, the wiring work between the lead wires is performed. In this case, the opening / closing mechanism 10 is covered by the cover portion 14-1 so that unexpected unexpected tripping caused by the operator touching the opening / closing mechanism 10 with a finger is not caused. Therefore, the assembly work of the product can be safely performed. After all the functional parts are mounted, the assembly of the product is completed by attaching the cover portion 14-2 and the top cover 4 of the auxiliary cover 14 to the top of the center cover 3.

In the above configuration, when the built-in accessory device (voltage trip device 17 and auxiliary and alarm switch 16 shown in FIG. 2) is mounted on or disconnected from the circuit breaker, the top cover 4 is shown in FIG. Open in the same manner as described for the configuration shown in. For this reason, it is possible to approach the accommodating part (concave part) of the accessory apparatus in the center cover 3, without attaching a finger to the opening / closing mechanism 10 at all, and to attach and detach an accessory apparatus safely.

While the invention has been particularly shown and described with reference to preferred embodiments, those skilled in the art will understand that the foregoing and other modifications may be made in form and detail without departing from the spirit and scope of the invention.

According to the present invention, the assembling structure of the molded case can be improved, thereby increasing the ease of assembling and the safety of the assembling work.

Claims (3)

A body case accommodating a contactor section, an arc-extinguishing device and an overcurrent tripping device; A central cover placed in the main body case and having a recess formed in a central portion thereof partitioned by a bottom wall, the central cover receiving an opening and closing mechanism and a built-in accessory; An upper cover covering an upper surface of the recess in the central cover The main body case, the center cover and the top cover is a circuit breaker arranged to be divided from each other, The central cover has an auxiliary cover coupled to the central cover to cover the opening and closing mechanism, and the upper cover is mounted on the auxiliary cover, And the auxiliary cover covers an area other than a receiving portion of the built-in accessory device, and the upper cover is hingedly coupled to an end of the auxiliary cover. delete 2. The auxiliary cover of claim 1, wherein the auxiliary cover is divided into a cover part covering the opening and closing mechanism, and a cover part covering a circumferential surface area of the opening and closing mechanism, and the cover part covering the opening and closing mechanism is mounted on the main body case. Circuit breaker.

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