CN212695110U

CN212695110U - Arc extinguishing chamber of circuit breaker with improved structure

Info

Publication number: CN212695110U
Application number: CN202021663744.9U
Authority: CN
Inventors: 陈红影; 刘洪武; 陈会林
Original assignee: Changshu Switchgear Manufacturing Co Ltd
Current assignee: Changshu Switchgear Manufacturing Co Ltd
Priority date: 2020-08-11
Filing date: 2020-08-11
Publication date: 2021-03-12
Anticipated expiration: 2030-08-11

Abstract

An arc extinguish chamber of a circuit breaker with an improved structure belongs to the technical field of low-voltage electrical appliances. The circuit breaker comprises a contact mechanism, wherein the contact mechanism comprises a moving contact and a fixed contact; the arc extinguishing chamber comprises an arc extinguishing grid group which is arranged at the position corresponding to the moving contact and the static contact and is formed by arranging a plurality of metal arc extinguishing grid pieces at intervals, and the arc extinguishing chamber also comprises at least one insulating piece which is fixed with the arc extinguishing grid piece group and extends out of the arc extinguishing grid piece group from the direction back to the moving contact in the arc extinguishing grid piece group. The advantages are that: because at least one insulating sheet is additionally arranged in the structural system of the arc-extinguishing grid sheet group, the insulating sheet is fixed with the arc-extinguishing grid sheet group and extends out of the arc-extinguishing grid sheet group from the inside of the arc-extinguishing grid sheet group to the direction back to the moving contact, the arc voltage required by front breakdown can be improved, and the risk that the front portion is broken down is reduced.

Description

Arc extinguishing chamber of circuit breaker with improved structure

Technical Field

The utility model belongs to the technical field of low-voltage apparatus, concretely relates to explosion chamber of institutional advancement's circuit breaker.

Background

As is known in the art, circuit breakers are typically deployed in power supply and distribution networks and function to limit or break fault currents in the power supply and distribution network. For example, when a large fault current occurs in an electric circuit, such as caused by overload, short circuit, etc., metal contacts of a circuit breaker, which are arranged in contact pairs (also called contact pairs), are separated from each other, an electric arc is generated between the two opposite contact pairs, and the electric arc is cut by arc-extinguishing bars arranged in a structural system of an arc-extinguishing chamber in the circuit breaker, so that the electric arc is quickly or instantly extinguished within a desired time, so as to prevent the electric arc from ablating the surfaces of the contact pairs and generating thermal ionized gas, i.e., high-temperature ionized gas to damage the circuit breaker shell, and prevent the internal pressure of the arc-extinguishing chamber from rising to cause the high-temperature gas to flow out of the circuit breaker shell to generate heat influence on equipment around the circuit breaker and even. In particular, since the arc gas contains metal ions, there is a risk of short-circuiting conductive members or electrical devices around the circuit breaker.

As can be seen from the above description, the arc extinguishing chamber is an important component of the circuit breaker, and the quality of the arc extinguishing capability (KA) of the arc extinguishing circuit directly affects the breaking capability of the circuit breaker on the fault circuit, the electrical life of the circuit breaker itself, and the electrical performance characteristics of the circuit breaker. The known arc extinguishing mechanism of the arc extinguishing chamber of the circuit breaker is as follows: the electric arc is driven to enter the arc extinguish chamber by virtue of the magnetic field generated by the conductive loop, and the long electric arc is cut into the multi-section short arcs connected in series by the arc extinguish grid sheet of the arc extinguish chamber, so that the arc extinguish is realized by improving the electric arc voltage.

The methods of increasing the arc extinguish chamber of the circuit breaker, lengthening the contact length to increase the contact opening distance, connecting a plurality of breakpoints in series and the like have positive effects on realizing high voltage and high breaking capacity of the low-voltage circuit breaker, but the method is realized by increasing the size of the circuit breaker, so the method is contrary to the spirit of modularization and miniaturization of the molded case circuit breaker, and the market competitiveness of the circuit breaker is influenced by correspondingly increasing the cost of the circuit breaker by increasing the size of the circuit breaker. Particularly, in the technical aspect, as the arc voltage of the arc extinguish chamber structure is increased in a high-voltage environment, the risk that the front part of the arc extinguish chamber of the high-voltage molded case circuit breaker is subjected to arc breakdown is increased. The technical solution described below is therefore to be created in this context, which is of positive significance for solving the technical problem of the front of the arc chute being subject to a breakdown.

Disclosure of Invention

The task of the utility model is to provide a help making the arc voltage that anterior breakdown produced improve and can show the explosion chamber of the circuit breaker of institutional advancement who reduces the anterior risk of suffering the breakdown.

The utility model aims to provide an arc extinguish chamber of a breaker with an improved structure, wherein the breaker comprises a contact mechanism which comprises a moving contact and a static contact; the arc extinguishing chamber comprises an arc extinguishing grid group which is arranged at the position corresponding to the moving contact and the static contact and is formed by arranging a plurality of metal arc extinguishing grid pieces at intervals, and the arc extinguishing chamber also comprises at least one insulating piece which is fixed with the arc extinguishing grid piece group and extends out of the arc extinguishing grid piece group from the direction back to the moving contact in the arc extinguishing grid piece group.

In a specific embodiment of the present invention, the plurality of metal arc-extinguishing grid pieces of the arc-extinguishing grid piece set and the insulating piece disposed between the metal arc-extinguishing grid pieces are disposed in a fan-shaped distribution state corresponding to the positions of the moving contact and the static contact.

In another specific embodiment of the present invention, the insulating sheet is provided with air holes, and when the insulating sheets are two or more, the arrangement directions of the adjacent insulating sheets are opposite and the positions of the air holes on the adjacent insulating sheets are staggered.

In another specific embodiment of the present invention, a moving contact arc striking plate is disposed at a position corresponding to an end of the arc extinguishing grid set facing to the moving contact.

In another specific embodiment of the present invention, the moving contact tab includes a moving contact tab main body and a moving contact tab extension, the moving contact tab main body corresponds to the arc extinguishing grid set orientation the one end portion that the moving contact is opened is set, the moving contact tab extension is composed of an automatic contact tab main body extending downward, and extends to an extent corresponding to the maximum position that the moving contact is opened.

In another specific embodiment of the present invention, a static contact striking plate is disposed between the position corresponding to the end of the static contact and the static contact.

In the utility model discloses a more and a concrete embodiment, the static contact arc starting piece by first race arc section I, second race arc section II and third race arc section III and constitute, first race arc section I one end with the static contact is connected, first race arc section I's the other end connect the one end of second race arc section II, the other end of second race arc section II is connected the one end of third race arc section III, and the other end of third race arc section III correspond to arc extinguishing grid piece group orientation the closed one end of moving contact.

In yet another specific embodiment of the present invention, the second running arc section ii is protruded from the first running arc section i and the third running arc section iii.

In a still more specific embodiment of the present invention, the left half of the second arc running section ii extends upward from the first arc running section i toward the direction of the arc extinguishing grid group, and the right half of the second arc running section ii extends to the third arc running section iii in a downward-inclined state from a position connected to the left half.

In yet another specific embodiment of the present invention, the first run arc section i and the third run arc section iii are horizontal sections.

The technical scheme technical effect of the utility model lie in, owing to add an at least piece of insulating piece in the structural system of arc extinguishing bars piece group, this insulating piece is fixed with arc extinguishing bars piece group to stretch out arc extinguishing bars piece group from the direction of arc extinguishing bars piece group inside to the moving contact dorsad, therefore enable the electric arc voltage improvement that anterior breakdown needs, thereby reduce the risk that the front portion was punctured.

Drawings

Fig. 1 is a schematic view of a first embodiment of the present invention.

Fig. 2 is a schematic view of the insulation sheet shown in fig. 1.

Fig. 3 is a schematic view of a second embodiment of the present invention.

Fig. 4 is a schematic view illustrating the arrangement of two insulation sheets shown in fig. 3.

Detailed Description

In order to make the technical essence and advantages of the present invention more clear, the applicant below describes in detail the embodiments, but the description of the embodiments is not a limitation of the present invention, and any equivalent changes made according to the inventive concept, which are only formal and not essential, should be considered as the technical scope of the present invention.

In the following description, unless otherwise specified, all the concepts related to the directions or orientations of up, down, left, right, front and rear are directed to the position state of fig. 1, and thus should not be interpreted as a specific limitation to the technical solution provided by the present invention.

Example 1:

referring to fig. 1, a contact mechanism 1 of a structural system of a circuit breaker is shown, wherein the contact mechanism 1 comprises a movable contact 11 and a fixed contact 12; the structural system of the arc extinguishing chamber is shown as an arc extinguishing grid group 2 which is arranged at the position corresponding to the moving contact 11 and the fixed contact 12 and is formed by arranging a plurality of metal arc extinguishing grid pieces 21 at intervals.

In accordance with the present invention, the circuit breaker is conventionally called a multi-pole circuit breaker because it has a plurality of poles, such as three poles or four poles, and also called a multi-pole molded case circuit breaker because the base and cover of the circuit breaker are generally molded of plastic. As is also known in the art, each pole typically comprises a contact mechanism as described above, i.e. comprising a stationary contact 12 as a fixed part or fixed contact and a movable contact 11 as a movable part or movable contact. When the circuit breaker is closed or opened, the moving contact 11 and the static contact 12 are closed or repelled, and the closing or repelled of the moving contact 11 and the static contact 12 is ensured by an operating mechanism not shown in the figure, that is, the moving contact is moved by the operating mechanism. The arc extinguishing grid set 2 is understood from the above words to be an arc extinguishing grid set for extinguishing the arc generated when the moving and

stationary contacts

11 and 12 are separated.

As can be seen from the schematic diagram in fig. 1, a part of the aforementioned fixed contact 12 is located below the arc-extinguishing chamber 5, an end of the fixed contact 12 is located at one side of the arc-extinguishing chamber 5, the movable contact 11 is located above an end of the fixed contact 12 and opposite to the arc-extinguishing chamber 5, and a free end of the movable contact 11 can be contacted with or separated from the end of the fixed contact 12 under the operation of the above-mentioned operating mechanism to realize the closing and opening of the low-voltage circuit breaker. As described above, in the open state of the circuit breaker, an arc is generated between the moving and

stationary contacts

11 and 12, the arc enters one side of the arc extinguishing chamber 5 shown in the drawing, and the other side of the arc extinguishing chamber 5 is defined as the front side of the arc extinguishing chamber 5 based on the expression of the one side.

As the technical scheme provided by the utility model: the arc-extinguishing chamber 5 further comprises an insulating sheet 22, and the insulating sheet 22 is fixed with the arc-extinguishing grid group 2 and extends out of the arc-extinguishing grid group 2 from the inside of the arc-extinguishing grid group 2 to the direction back to the movable contact 11. That is, the other side of the insulation sheet 22, which generates arc between the moving and

stationary contacts

11 and 12 in the open state of the circuit breaker, extends out of the metal arc chute sheet 21 of the arc chute sheet set 2. Preferably, as shown in fig. 1, the side of the insulating sheet 22 where the arc is generated between the moving and

stationary contacts

11 and 12 in the open state of the circuit breaker also extends out of the metal arc chute pieces 21 of the arc chute piece group 2.

The plurality of metal arc-extinguishing grid pieces 21 of the arc-extinguishing grid set 2 and the insulating piece 22 arranged between the metal arc-extinguishing grid pieces 21 are arranged in a fan-shaped distribution state corresponding to the positions of the movable contact 11 and the fixed contact 12.

Referring to fig. 2, the insulating sheet 22 is provided with a vent hole 221. The sector state is in a circular arc state.

In the present embodiment, the one insulating sheet 22 is provided in a region where front side breakdown is likely to occur in the open state of the circuit breaker, that is, in a region where front side breakdown is likely to occur in the front of the arc extinguishing chamber 5. The insulating sheet 22 is fixed to the arc chute group 2 in various ways, preferably, as shown in fig. 1, the insulating sheet 22 and the metal arc chute pieces 21 of the arc chute group 2 are arranged between the metal arc chute pieces 21 in parallel at intervals, and the insulating sheet 22 is fixed to an arc-isolating wall (not shown) for fixing the metal arc chute pieces 21. Other embodiments are also possible, such as the insulating sheet 22 being directly fixed to the metal arc chute 21 and the insulating sheet 22 being fixed to the metal arc chute 21. Naturally, the invention is not limited to the two embodiments described above, as long as it is achieved that the insulating sheet 22 projects beyond the metal arc chute 21 in a direction away from the movable contact 11 in a feasible manner. Since the other side of the insulating sheet 22, which generates an arc between the moving and

stationary contacts

11, 12 in the open state of the circuit breaker, extends out of the metal arc chute 21, the arc voltage required for front breakdown can be increased, thereby significantly reducing the risk of front breakdown, or even if front breakdown occurs, the arc voltage will not be significantly reduced. In addition, after the insulating sheet 22 is attached, in order to ensure smooth current flow inside the arc-extinguishing chamber, the insulating sheet 22 is provided with a vent hole 221.

Continuing to refer to fig. 1, a moving contact arc piece 3 is disposed at a position corresponding to an end portion of the arc-extinguishing grid set 2 facing to an opening end of the moving contact 11, the moving contact arc piece 3 includes a moving contact arc piece main body 31 and a moving contact arc piece extension body 32, the moving contact arc piece main body 31 is disposed corresponding to the end portion of the arc-extinguishing grid set 2 facing to the opening end of the moving contact 11, and the moving contact arc piece extension body 32 is formed by extending downward the moving contact arc piece main body 31 and extends to a degree corresponding to a maximum position of the moving contact 11.

As shown in fig. 1, the tail end of the moving contact arc striking sheet extension 32 is formed into a U shape, and in a state of a maximum position where the moving contact 11 is opened, a current path can be formed between a U-shaped portion and the moving contact end portion 111 of the moving contact 11, and the U-shaped structure of the moving contact arc striking sheet extension 32 greatly enhances the electric field intensity at this position (U-shaped portion), so that electric arc striking is facilitated to be induced into the arc extinguishing chamber 5, the length of the electric arc is lengthened, the electric arc voltage is increased, and the breaking capacity of the circuit breaker is extremely improved.

Continuing to refer to fig. 1, a static contact arc striking plate 4 is arranged between a position corresponding to an end portion of the arc-extinguishing grid group 2 facing to one end of the static contact 12 and the static contact 12, the static contact arc striking plate 4 is composed of a first arc running section i 41, a second arc running section ii 42 and a third arc running section iii 43, one end of the first arc running section i 41 is connected with the static contact 12, the other end of the first arc running section i 41 is connected with one end of the second arc running section ii 42, the other end of the second arc running section ii 42 is connected with one end of the third arc running section iii 43, and the other end of the third arc running section iii 43 corresponds to one end of the arc-extinguishing grid group 2 facing to the movable contact 11.

The second arc running section II 42 protrudes from the first arc running section I41 and the third arc running section III 43; the left half of the second arc-extending section ii 42 extends upward from the first arc-extending section i 41 toward the arc-extinguishing grid group 2, and the right half of the second arc-extending section ii 42 extends downward from the position connected with the left half to the third arc-extending section iii 43.

As shown in fig. 1, the first arc segment i 41 and the third arc segment iii 43 are horizontal segments.

As shown in fig. 1, the entire static contact arc striking plate 4 is substantially located at the bottom of the arc extinguishing grid group 2, one end, i.e., the first arc running section i 41, is fixedly connected to the end of the static contact plate 121 of the static contact 2, the other end, i.e., the third arc running section iii 43, extends to the lower side of the arc extinguishing grid group 2, and the middle, i.e., the second arc running section ii 42, is a transition section.

Example 2:

referring to fig. 3 and 4, in the present embodiment 2, the number of the insulation sheets 22 is increased to two compared to the one of the embodiment 1, and since two insulation sheets 22 are used, the arrangement directions of the insulation sheets 22 are opposite and the positions of the vent holes 221 on the two insulation sheets 22 are staggered (see fig. 4 specifically). The rest is the same as described in example 1.

The applicant needs to state that: the number of the insulating sheets 22 described above is not limited to embodiment 1 and embodiment 2.

Because the utility model discloses install the insulating piece 22 with insulating material processing in the region that easily produces the front portion and puncture, the length extension of this insulating piece 22 makes the front portion puncture required arc voltage improve to reduce the risk of front portion puncture, or even the front portion puncture arc voltage also can not show the decline; the insulating sheet 22 is lengthened, and the insulating sheet 22 is provided with air holes 221, so that the smoothness of the air flow inside the arc extinguish chamber 5 is ensured; after the air holes 221 are opened on the insulating sheet 22, when two insulating sheets 22 are used, the staggered arrangement is implemented to prevent the electric arc from staying at the air holes 221, thereby reducing the penetration of the air holes.

To sum up, the technical solution provided by the present invention remedies the defects in the prior art, successfully completes the invention task, and faithfully embodies the technical effects mentioned in the above technical effect column by the applicant.

Claims

1. An arc extinguish chamber of a circuit breaker with an improved structure is disclosed, wherein the circuit breaker comprises a contact mechanism (1), and the contact mechanism (1) comprises a moving contact (11) and a fixed contact (12); the arc extinguishing chamber comprises an arc extinguishing grid group (2) which is arranged at the position corresponding to the moving contact (11) and the static contact (12) and is formed by arranging a plurality of metal arc extinguishing grid pieces (21) at intervals, and is characterized by further comprising at least one insulating piece (22), wherein the insulating piece (22) is fixed with the arc extinguishing grid group (2) and extends out of the arc extinguishing grid group (2) from the direction back to the moving contact (11) in the arc extinguishing grid group (2).

2. The arc extinguishing chamber of the circuit breaker with the improved structure according to claim 1, characterized in that a plurality of metal arc extinguishing grid pieces (21) of the arc extinguishing grid set (2) and the insulating pieces (22) arranged between the metal arc extinguishing grid pieces (21) are arranged in a fan-shaped distribution state corresponding to the positions of the moving contact (11) and the static contact (12).

3. The arc chute of a structurally improved circuit breaker according to claim 1 or 2, characterized in that a vent hole (221) is opened on the insulating sheet (22), and when the insulating sheets (22) are two or more, the arrangement directions of the adjacent insulating sheets (22) are opposite and the positions of the vent holes (221) on the adjacent insulating sheets (22) are staggered from each other.

4. Arc chute of a structurally improved circuit breaker according to claim 1, characterized in that a moving contact tab (3) is provided in a position corresponding to the end of said arc chute group (2) facing the end of said moving contact (11) that is open.

5. The arc extinguish chamber of the circuit breaker with the improved structure as claimed in claim 4, wherein the moving contact arc piece (3) comprises a moving contact arc piece main body (31) and a moving contact arc piece extension body (32), the moving contact arc piece main body (31) is arranged corresponding to one end part of the arc extinguish grating group (2) which is opened towards the moving contact (11), and the moving contact arc piece extension body (32) is formed by extending the moving contact arc piece main body (31) downwards and extends to the extent corresponding to the maximum position of the moving contact (11) when the moving contact is opened.

6. Arc chute of a structurally improved circuit breaker according to claim 1, characterized in that a stationary contact tab (4) is provided between a position corresponding to an end of the arc chute group (2) facing the stationary contact (12) and the stationary contact (12).

7. The arc extinguish chamber of the circuit breaker with the improved structure according to claim 6, wherein the fixed contact arc striking plate (4) consists of a first arc running section I (41), a second arc running section II (42) and a third arc running section III (43), one end of the first arc running section I (41) is connected with the fixed contact (12), the other end of the first arc running section I (41) is connected with one end of the second arc running section II (42), the other end of the second arc running section II (42) is connected with one end of the third arc running section III (43), and the other end of the third arc running section III (43) corresponds to the end of the arc extinguish grid group (2) closed towards the movable contact (11).

8. Arc chute of a structurally improved circuit breaker according to claim 7, characterized in that said second arc running section ii (42) is raised from said first arc running section i (41) and from said third arc running section iii (43).

9. The arc chute of a structurally improved circuit breaker according to claim 8, characterized in that a left half of said second arc running section ii (42) extends upward from said first arc running section i (41) toward said arc extinguishing grid assembly (2), and a right half of said second arc running section ii (42) extends from a position connected to said left half to said third arc running section iii (43) in a downwardly inclined state.

10. The interrupting chamber of a structurally improved circuit breaker according to claim 7, 8 or 9 characterized in that said first run i (41) and third run iii (43) are horizontal.