KR101061272B1 - Circuit breaker - Google Patents

Abstract

The problem of the present invention is to provide a stopper function for stopping the movable contactor at the open end position and a shielding function for preventing the diffusion of arc gas into the opening and closing mechanism or the operation handle to the cover itself of the body case, thereby reducing the number of parts. It is to provide an improved circuit breaker that can reduce the cost and cost.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, the fixed case 6, the movable contact 7, and the arc scavenging chamber arc in the main body case 1 made of mold resin which consists of the base 2 and the cover 3; a functional block of the current interrupting unit (9), the opening / closing mechanism (10), the locker operation handle (11), and the overcurrent trip device (12), and the opening / closing mechanism (10) and the operation. A multi-pole type circuit breaker in which the handle 11 is housed in a polar chamber partitioned at the left and right centers of the main body case 1, and the top of the arc elimination chamber 9 is housed inside the cover 3. The stopper which integrally forms the barrier partition 3b which partitions a space, and stops the movable contact 7 which opens from the fixed contact 6 at the front-end | tip part of the barrier partition 3b at an opening end position. The part 3c is formed.

Description

Circuit breaker {CIRCUIT BREAKER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multipolar circuit breaker for circuit breakers, earth leakage breakers, and the like, and more particularly, to a structure of a main body case in which functional parts of a circuit breaker are assembled.

The above-mentioned circuit breaker includes a current blocking portion, an opening and closing mechanism, comprising a fixed contactor, a movable contactor, an arc elimination chamber, and a main body case made of a mold resin including a base and a cover. A rocker-type operation handle and each functional part of the overcurrent trip device are mounted to each other (for example, refer to Patent Document 1).

Next, the structure of the 3-pole circuit breaker applied to the three-phase circuit disclosed by patent document 1 as a conventional example is shown in FIG. In the figure, 1 is a main body case made of a molded resin having a divided structure of a box-shaped base 2 and a cover 3, 4 is a power supply terminal, 5 is a load side terminal, 6 is a fixed contact, 7 is a movable contact, 7a denotes a support shaft of the movable contact 7, 8 denotes a contact holder for axially holding the movable contact 7 of each pole, 9 denotes a grid arc elimination chamber, and 10 denotes the contact holder ( 8) an open / close mechanism having a toggle link mechanism and a latch, 11 is a locker operation handle connected to the open / close mechanism 10, 11a is a handle of the operation handle, 12 is a bimetal and an electromagnet. The combined thermal-electronic overcurrent trip device 13 is a trip cross bar for tripping the switching mechanism 10 in response to a mechanical operation signal of the overcurrent trip device 12.

Here, inside the main body case 1, three pole chambers corresponding to the phases of R, S, and T of the three-phase main circuit are partitioned from side to side with the interphase partition walls interposed therebetween. A fixed contact 6, a movable contact 7, and an overcurrent trip device 12 are connected and disposed between the power supply terminal 4 and the load side terminal 5 for each pole room, and the opening movement path of the movable contact 7 is also provided. The arc elimination chamber 9 is arrange | positioned along the power supply side.

Moreover, the opening / closing mechanism 10 and the operation handle 11 which are common to each pole are accommodated and arrange | positioned at the upper side (cover side) of the center polar chamber corresponding to S phase among the polar chamber partitioned inside the main body case 1, The knob 11a of the operating handle 11 protrudes outward through the handle hole 3a opened in the center of the upper surface of the cover 3 at the receiving position.

The current interruption operation of the circuit breaker configured as described above is described in detail in Patent Document 1, and when a relatively small overcurrent such as an overload current continues to flow, the bimetal of the overcurrent trip device 12 is bent and its operation stage I) presses the lever of the trip cross bar 13, and it follows and releases the latch of the opening-closing mechanism 10. Accordingly, the opening and closing mechanism 10 trips, and the opening and closing spring rotates the contact holder 8 clockwise, and moves the movable contact 7 held by the contact holder 8 to the open position. Move to cut off the current.

When an excessive current such as a short-circuit current flows, the overcurrent tripping device 12 acts between the fixed contact 6 and the movable contact 7 without waiting for a tripping operation of the opening and closing mechanism 10 by the electromagnet of the overcurrent trip device 12. The movable contact 7 first starts the opening operation by the electromagnetic repulsive force, and the opening / closing mechanism 10 trips a little later than this to drive the contact holder 8 clockwise, and is held in the contact holder 8. The movable contact 7 is moved to the open position to cut off the current. In addition, the arc generated between the contact of the fixed contactor 6 and the movable contactor 7 at the time of the current interruption receives the electromagnetic driving force and the pressure of the arc gas generated in the circumferential region of the arc. It is well known that it is driven in the arc erasing chamber 9, and is pushed in between the grid plates and dissipated (current blocking).

On the other hand, in the circuit breaker of FIG. 7, in order to stop the movable contact 7 which is rapidly driven from the closed pole position to the open pole position at the above-described current blocking operation, a metal is made inside the main body case 1. The stopper pin 14 of the stopper pin 14 into the recess groove formed in the overlapping surface of the base 2 and the cover 3 to hold the movable contact 7 moved to the open end position. It hits the stopper pin 14 and makes it stop at that position.

In addition, with respect to the central polar chamber of the main body case 1 which accommodated the opening-closing mechanism 10 and the operation handle 11, the arc gas (arc gas produced | generated in the space in the arc elimination chamber by the heat of the arc which generate | occur | produced between the fixed / movable contacts) (Includes soot carbides generated from the mold wall of the mold resin in contact with the high temperature arc, and metal particles evaporated from the fixed and movable contact surfaces). 10) or to the operation handle 11, which is shielded on the upper surface side of the arc elimination chamber 9 in the structure of FIG. 7 to prevent the deterioration of insulation of the operation handle and the deterioration of the operation of the opening and closing mechanism. A plate (fiber) 15 is laid so as to isolate the space of the arc eliminating chamber 9 from the opening / closing mechanism and the operation handle.

[Patent Document 1] Japanese Patent Laid-Open No. 2000-67730 (FIG. 1)

However, the circuit breaker of the conventional example shown in FIG. 7 has the following problems.

First, a means for stopping the movable contact opened from the fixed contact by the current blocking operation, the OFF operation of the operating handle at the open end position, and the arc gas generated by the current blocking diffuses from the arc elimination chamber toward the switching mechanism and the operating handle. In the conventional structure, as a means of preventing the occurrence of the components, the parts such as the stopper pin 14 and the shielding plate 15 are combined in the main body case 1, which increases the number of parts of the circuit breaker and the number of assembling steps, thereby increasing the cost. ) Caused an increase.

Moreover, in the structure which inserted the said stopper pin 14 in the groove formed in the base 2 of the main body case 1, and the fitting surface of the cover 3, the operation handle 11 faces in front of the board. If the cover 3 is peeled off during the maintenance of the circuit breaker provided, the stopper pin 14 may fall off. In addition, when the movable contactor 7 (copper material) collides with the stopper pin 14 made of metal subjected to arc heat to a high temperature, both of them are welded so that the movable contactor 7 does not return to the closed position after the current is interrupted. It may cause trouble.

This invention is made | formed in view of the said point, The objective is providing the cover itself of the main body case with the stopper function which stops a movable contactor to an opening terminal position, and the shielding function which prevents the arc gas diffusion to an opening / closing mechanism or an operation handle. In order to reduce the number of parts and reduce the cost, the circuit breaker is improved.

In order to achieve the above object, according to the present invention, a main body case made of a mold resin consisting of a base and a cover, a fixed contactor, a movable contactor, a current interruption unit consisting of an arc erasing chamber, an opening and closing mechanism, a locker type operation handle, And a multi-pole circuit breaker equipped with respective functional parts of the overcurrent trip device and accommodating the opening and closing mechanism and the operation handle in the polar chamber partitioned at the left and right centers of the main body case. An angle of integrally forming a barrier partition that partitions between the mechanisms, and stopping the movable contact that is opened from the fixed contact at the distal end of the barrier partition at an open end position Form a stopper part consisting of two end faces of different collisions (claim 1).

Moreover, in the said structure WHEREIN: About the center polar chamber of the main body case which accommodates an operation handle and an opening / closing mechanism, it covers the empty part opened to the cover of a main body case according to the molding process of the barrier rib formed in the said polar chamber, and a stopper part. A shielding cover is to be deposited on the upper surface (claim 2). The shielding cover is fitted to the handle portion of the operation handle and slides an end portion of the shielding sheet extending in the handle operation direction from above. A member that also serves as a retaining guide for guiding the gap between the two and the above, wherein the shielding cover is superimposed on the upper surface of the cover of the main body case, and then tightened together to the base by a fastening screw to fix it (claim 3).

According to the above configuration, the barrier partition wall integrally formed on the cover of the main body case, omitting each of the stopper pins provided in the circuit breaker of the conventional structure, the shield plate of the arc elimination chamber (see FIG. 7), and the The stopper portion formed in the partition wall ensures a stopper function for stopping the movable contactor at the open end position, and a shielding function for preventing the arc gas diffusion to the opening and closing mechanism and the operation handle. As a result, not only the number of parts and the number of assembly steps can be reduced, but also the cost of the product can be reduced as compared with the circuit breaker of the conventional structure.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described based on the Example shown to FIGS. For reference, FIG. 1 is a perspective cross-sectional view showing the internal structure of a circuit breaker (wiring breaker), FIG. 2 is a cross-sectional view of the cover of the main body case shown in FIG. 1, and FIG. 4 is an external perspective view of the cover illustrated in FIG. 2, and FIG. 5 is an exploded perspective view of the circuit breaker illustrated in FIG. 1, and FIG. 6 is a structural diagram of a shielding cover mounted on the cover. The same code | symbol is used for the member corresponding to FIG. 7, and the description is abbreviate | omitted.

The circuit breaker of the illustrated embodiment is basically the same as that of the conventional example shown in Fig. 7, but includes a cover which is combined with the base 2 with respect to the main body case 1 made of a mold resin for accommodating each functional part of the circuit breaker ( 3) is composed as follows.

That is, as shown in Fig. 2 and Fig. 3, inside the cover 3, the cover 3 is arranged downward so as to partition the accommodating space at the top of the arc erasing chamber 9 (see Fig. 1) provided in each pole chamber in the main body case. An extended barrier partition 3b is integrally formed, and a stopper portion 3c which allows the movable contact 7 opened from the fixed contact 6 to hit the lower end of the barrier partition 3b so as to stop at the open end position. ) Is formed. In addition, the cover 3 has an interphase partition wall which partitions the polar chamber arranged left and right corresponding to each of the bearing frame 3d of the contact holder 8 and the R, S, and T phases of the main circuit as in the conventional example. (3e) is formed, and the opening-closing mechanism 10 and the operation handle 11 shown in FIG. 1 are housed | arranged and arrange | positioned at the central pole room (S phase).

In addition, as shown in FIG. 4, the recessed part of the pocket shape which inserts and sets accessory apparatuses, such as an auxiliary switch and an alarm switch, on both left and right sides with the accommodating part of the operation handle 11 on the upper surface side of the cover 3, and is set. 3f is formed, and the top cover 16 which can be opened and closed is provided with the cover 3 so that the said recessed part 3f may be covered.

In the circuit breaker of Fig. 1 in which the functional parts are mounted on the main body case 1 in which the cover 3 is combined with the base 2, the movable contact 7 is fixed by the tripping contact and the OFF operation of the handle. When opening and opening from 6), the movable contact 7 hits the end surface of the stopper portion 3c formed in the cover 3 at its opening end position and stops at that position. In addition, the arc gas generated in the space of the arc elimination chamber 9 due to the overcurrent blocking operation is prevented by the barrier partition 3b and is not directly ejected to the space accommodating the opening / closing mechanism 10 and the operation handle 11. Instead, it flows through the grid plates of the arc erasing chamber 9 and is discharged outward from the end (power supply side) of the main body case 1.

Thereby, like the circuit breaker of the conventional example shown in FIG. 7, parts, such as the stopper pin 14 and the shielding plate 15 which cover the upper part of the arc elimination chamber 9, are further arrange | positioned inside the main body case 1. The stopper function and the opening / closing mechanism 10 which stop the movable contact 7 at the opening end position by the barrier partition 3b and the stopper part 3c which were integrally formed in the cover 3 made of a mold resin without the necessity. ) And a shielding function for preventing the arc gas diffusion into the operation handle 11 can be secured. Therefore, the cost can be reduced by reducing the number of parts and the number of assembly steps compared to the circuit breaker of the conventional example.

Moreover, according to the model of a circuit breaker, the structure which the center of the support shaft of the movable contact 7 and the center of the rotation shaft of the contact holder 8 which hold | maintain and hold | maintain the said movable contact 7 are concentric, and the eccentricity There is a structure. Further, in the latter structure, the contact holder 8 is rotated by the movement trajectory of the movable contact 7 which is opened by receiving the electromagnetic repulsive force and the tripping operation of the opening / closing mechanism 10 to move the movable contact 7 to the open position. The moving trajectory to drive is different. For this reason, some shift | offset | difference arises in the collision position and angle of the movable contact 7 which collide with the stopper part 3c in an open end position. Therefore, in the stopper part 3c formed in the cover 3 of the illustrated embodiment, the angle is changed in the stopper part 3c so as to cope with the collision position and the shift of the angle of the movable contact 7 as shown in FIG. A two-stage collision end surface is formed, and in any case, the movable contact 7 which has moved to the open position is brought into contact with the surface to stop. For reference, the stopper portion 3c may be formed only in the S phase.

By the way, in the cover 3 of the illustrated embodiment, the shape of the stopper portion 3c formed in the barrier partition 3b of the polar chamber S-phase lined up in the center is so as to avoid interference with the operation handle 11. It cut so that it might protrude toward the opening-closing mechanism 10 from the front end of the barrier rib 3b, and the hollow part 3g was formed above it (refer FIG. 2). For this reason, since the slide core is needed for the undercut process of the said stopper part 3c in the mold metal mold | die which covers the cover 3, the hole which leads to the said hollow part 3g in the upper surface of the molded cover 3 is formed. (Hole for setting the slide core) is opened.

However, if the opening hole is left unblocked, the driver is opened when the upper cover 16 (see Fig. 1) is opened and the attachments such as the auxiliary switch mentioned above are attached to the recesses 3f of the cover 3. There is a risk that the tip of the (tool) enters the empty portion 3g through the opening hole and contacts the live part. Therefore, in the illustrated embodiment, a shield cover 17 (molded resin molded article), which is a separate component, is deposited on the upper surface of the cover 3 so as to close the hole of the empty portion 3g (FIG. 1 and 5). In addition, in the illustrated embodiment, the gap left between the operation handle 11 and the peripheral edge of the handle hole 3a opened on the upper surface of the cover 3 is prevented, so that dust or the like enters into the case from the outside. As a means for preventing from being made, a flexible shield sheet 18 is provided that is fitted to the handle portion 11a of the operation handle 11 and extends back and forth separately from the shield lid 17. Then, the end of the sheet was extended to cover the opening hole of the empty portion 3g with the shielding sheet 18, and then the extended end was guided to the shielding cover 17. The detailed structure will be described below with reference to FIGS. 5 and 6.

That is, as shown in (a) and (b) of FIG. 6, the shielding cover 17 has a screw sheet 17a protruding from both the left and right sides and a lower end of the cover plate to protrude to the end of the shielding sheet 18. U-shaped guides 17b for guiding and holding the guides, and extension piece portions 17c extending forward are formed. On the other hand, the recessed part 3i corresponding to the extension piece part 17c of the said shielding cover 17 is formed in the upper surface of the cover 3.

Then, in the final assembly process of the circuit breaker in which various functional parts are mounted on the base 2 of the main body case 1, the cover 3 is covered by the base 2, and then the empty portion opened on the upper surface of the cover ( The end of the shielding sheet 18 which overlaps the shielding cover 17 in the predetermined position so that the hole of 3g) may be overlapped, and was previously fitted and laid in the grip part 11a of the operation handle 11 in this position. Is inserted into the U-shaped guide (17b) of the shield cover (17). In this state, the screw 19 (see FIG. 5) passed through the screw seat 17a of the shielding cover 17 and the attachment screw hole 3h formed in the cover 3 is screwed to the base 2. And fix the cover 3 and the shield cover 17 together.

In the assembled state, as shown in FIG. 1, the hole of the empty portion 3g opened in the upper surface of the cover 3 for the undercut treatment during the molding process is provided with the shielding cover 17 and the shielding sheet 18. And the end of the shielding sheet 18 is inserted between the recess 3i formed on the upper surface of the cover 3 and the extension piece 17c of the shielding cover 17 so as to be slidably guided. Will be.

1 is a side cross-sectional view illustrating an assembly structure of a circuit breaker according to an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view of the cover of the main body case shown in FIG. 1. FIG.

3 is an external perspective view of the cover of FIG. 2 viewed from the back side.

4 is an external perspective view of the cover of FIG. 2 viewed from an upper surface side thereof.

5 is an exploded perspective view of a main body case of the circuit breaker shown in FIG. 1.

FIG. 6: is a structural diagram of the shielding cover shown in FIG. 5, (a) is an external view seen from the back surface side, (b) is a front view.

7 is a perspective sectional view showing an assembling structure of a circuit breaker of a conventional example.

Explanation of symbols on main parts of drawing

1: body case 2: base

3: cover 3a: handle hole

3b: barrier partition 3c: stopper portion

6: fixed contact 7: movable contact

8 contact holder 9 arc eliminating chamber

10: opening and closing mechanism 11: operation handle

12: overcurrent trip device 17: shield cover

17a: screw seat 18: shielding sheet

Claims (3)

A multi-pole type in which a main body case made of a molded resin comprising a base and a cover is mounted with a fixed contactor, a movable contactor, a current interrupter consisting of an arc eliminating chamber, an opening / closing mechanism, a locker-type operation handle, and an overcurrent trip device. The circuit breaker of which the said opening | closing mechanism and an operation handle were accommodated and arrange | positioned in the polar chamber partitioned in the left and right center of a main body case, A barrier partition partitioning between the arc elimination chamber and the opening / closing mechanism is integrally formed inside the cover, and at the distal end of the barrier partition wall, a movable contact that opens from a fixed contact is opened. A circuit breaker comprising: a stopper portion having two end faces of collision at different angles to stop at a terminal position. The method of claim 1, About the central polar chamber of the main body case which accommodates an operation handle and an opening / closing mechanism, it covers the empty part opened to the cover of the main body case by the mold shaping | molding process of the barrier rib and the stopper part formed in the said polar chamber, and attaches a shielding cover to the cover upper surface. Circuit breaker characterized in that the (被 着). 3. The method of claim 2, The shielding cover serves as a retaining guide which is fitted to the handle portion of the operation handle and pushes an end portion of the shielding sheet extending in the handle operation direction from above to guide the gap between the cover and the cover. The circuit breaker, characterized in that overlapping the upper surface of the cover, and then fastened together to the base by a fastening screw.

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