Arc elimination device and molded case circuit breaker

Abstract

The present invention relates to the field of molded case circuit breakers, and relates in particular to an arc elimination device and a molded case circuit breaker. The arc elimination device comprises a housing. At least one exhaust channel is arranged inside the housing. The exhaust channel is provided with an air inlet and an air outlet, at least one arc extinguishing plate is arranged in the exhaust channel, and the exhaust channel is provided with at least one bend between the air inlet and the air outlet. Since the present invention provides at least one bend in the exhaust channel, the length of the exhaust channel is not limited by the size of the arc elimination device and can be increased, thereby enhancing the effect of arc elimination.

Description

Arc elimination device and molded case circuit breaker Technical Field

[0001] The present invention belongs to the field of molded case circuit breakers, and in particular relates to an arc elimination device and a molded case circuit breaker. Background Art

[0002] The arcing safety issue in the molded case circuit breaker industry has always attracted much attention. When the short-circuit protection of the molded case circuit breakers on the market is disconnected, arcing sparks are often emitted, posing a great safety hazard. The reason is that there is no arcing exhaust channel, or the arcing exhaust channel is very short, resulting in large arcing sparks outside the circuit breaker. In the prior art, to address the arcing problem, arc extinguishing devices are installed at the arcing location outside the circuit breaker. For example, structures disclosed in Chinese patents CN202120649600.6, CN202223464249.7, CN201620915493.6, and CN201520904965.3 generally include a cover connected to the circuit breaker housing and a plurality of arc extinguishing plates fixed within the cover. The cover provides a channel for arc exhaust, and the arc is extinguished by layering and cooling the arc through the plurality of arc extinguishing plates. However, in practice, due to installation space limitations, the cover length is insufficient and cannot be further increased. Therefore, the arc extinguishing effect needs to be improved. Technical issues

[0003] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide an arc elimination device and a molded case circuit breaker. Technical Solutions

[0004] The technical solution adopted by the present invention is as follows: an arc elimination device, including a cover body, wherein at least one exhaust channel is provided in the cover body, the exhaust channel has an air inlet and an air outlet, at least one arc extinguishing plate is provided in the exhaust channel, and the exhaust channel has at least one bend between the air inlet and the air outlet.

[0005] The exhaust channel has at least one Venturi structure unit, which has an inlet section with a flow cross-sectional area of ​​S1, a throat section with a flow cross-sectional area of ​​S2, and a diffusion section with a flow cross-sectional area of ​​S3, where S1 is greater than S2 and S3 is greater than S2.

[0006] The front end of the curve is connected to a first transition channel and the rear end of the curve is connected to a second transition channel. The flow cross-sectional area of ​​the rear end of the first transition channel is greater than or equal to the flow cross-sectional area of ​​the front end of the curve to which it is connected. The flow cross-sectional area of ​​the front end of the second transition channel is greater than or equal to the flow cross-sectional area of ​​the rear end of the curve to which it is connected. The first transition channel, the curve, and the second transition channel connected in sequence along the fluid flow direction constitute a Venturi structure unit, and the curve is the throat section of the Venturi structure unit.

[0007] The exhaust channel has at least two bends. Among the two adjacent bends, the second transition channel connected to the front bend also constitutes the first transition channel connected to the rear bend, and the flow cross-sectional area at the front end of the second transition channel is larger than the flow cross-sectional area at the rear end of the bend to which it is connected.

[0008] The first transition channel and the second transition channel are both trumpet-shaped channels with a flow cross-sectional area at the front end being larger than a flow cross-sectional area at the rear end. The flow cross-sectional area at the rear end of the first transition channel is equal to the flow cross-sectional area at the front end of the bend to which it is connected. The connecting portion between the first transition channel and the bend is a smooth inner wall; the front end of the second transition channel forms a widened groove on one side or both sides of the end of the bend.

[0009] The arc extinguishing plate is fixed in the middle of the second transition channel, and a plurality of arc extinguishing plates are arranged between the bend at the rear end and the air outlet.

[0010] At least one second mounting cavity is provided in the cover body, a channel forming block is fixed in the second mounting cavity, a flow channel groove is provided on one side or both sides of the channel forming block, an exhaust channel is formed by the flow channel groove on the side of the channel forming block and the inner wall of the second mounting cavity or the inner wall of the second mounting cavity and the inner wall of the circuit breaker housing, the cover body is respectively provided with a first opening and a second opening corresponding to the air inlet and the air outlet of the exhaust channel, and the arc extinguishing plate is fixed in the flow channel groove.

[0011] The cover body is provided with a second installation opening for the channel forming block to be inserted into the second installation cavity.

[0012] A molded case circuit breaker comprises a circuit breaker body, the circuit breaker body comprising a circuit breaker housing and a contact system, an operating mechanism, an arc extinguishing system, and an overload protection system located within the circuit breaker housing. The circuit breaker housing is provided with an arc discharge outlet corresponding to the arc output end of the arc extinguishing system. The circuit breaker is characterized in that it further comprises the arc extinguishing device as described above, the air inlet of the arc extinguishing device being connected to the arc discharge outlet of the circuit breaker housing for collecting gas discharged from the circuit breaker body.

[0013] The circuit breaker housing forms an arc discharge outlet above the arc extinguishing system and at the tail of the arc extinguishing system, and the arc extinguishing device is connected above the base and on the side of the upper cover. Beneficial effects

[0014] The beneficial effects of the present invention are as follows: since the present invention provides at least one bend in the exhaust passage, the length of the exhaust passage can be increased without being limited by the size of the arc elimination device, thereby increasing the effect of eliminating arcs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, other drawings obtained based on these drawings still fall within the scope of the present invention.

[0016] FIG1 is a schematic structural diagram of a molded case circuit breaker according to an embodiment of the present invention;

[0017] FIG2 is an exploded view of a molded case circuit breaker according to an embodiment of the present invention;

[0018] FIG3 is a cross-sectional view of a molded case circuit breaker according to an embodiment of the present invention;

[0019] FIG4 is a schematic structural diagram of a circuit breaker body according to an embodiment of the present invention;

[0020] FIG5 is an exploded view of a circuit breaker body according to an embodiment of the present invention;

[0021] FIG6 is a schematic structural diagram of an upper cover in one embodiment of the present invention;

[0022] FIG7 is a schematic structural diagram of a base in one embodiment of the present invention;

[0023] FIG8 is a cross-sectional view of an arc elimination device according to an embodiment of the present invention;

[0024] FIG9 is a schematic structural diagram of a cover body according to an embodiment of the present invention;

[0025] FIG10 is a schematic structural diagram of a channel forming block equipped with an arc extinguishing plate in one embodiment of the present invention;

[0026] FIG11 is a side view of a channel forming block in one embodiment of the present invention;

[0027] FIG12 is a schematic structural diagram of an arc extinguishing plate in one embodiment of the present invention;

[0028] In the figure,

[0029] Circuit breaker body 100, circuit breaker housing 110, base 111, first connecting plate 1111, first limiting slot 1112, limiting step 1113, upper cover 112, second connecting plate 1121, second limiting insert 1122, first vertical partition 113, second vertical partition 114, arc discharge outlet 115, first wiring support 116, second wiring support 117, contact system 120, moving contact 121, static contact 122, first conductive terminal 123, second conductive terminal 124, operating mechanism 130, operating handle 131, arc extinguishing system 140;

[0030] Arc extinguishing device 200, exhaust channel 210, air inlet 211, air outlet 212, bend 213, widened groove 214, channel forming block 220, flow channel groove 221, arc extinguishing plate slot 222, arc extinguishing plate 231, small hole 232, cover 240, second mounting cavity 241, first opening 242, second opening 243, first connecting platform 244, second connecting platform 245, partition 246, first limiting insert 247, first side plate 248, second limiting slot 249;

[0031] Terminal block extension plate-300. Best Mode for Carrying Out the Invention

[0032] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be described in further detail below with reference to the accompanying drawings.

[0033] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for the purpose of distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. Subsequent embodiments will not explain this one by one.

[0034] The terms "upper," "lower," "front," "back," "left," "right," "inner," "outer," "top," "bottom," and "side" used herein are merely references to the directions or positions in the accompanying drawings. These terms are intended to illustrate and facilitate understanding of the present invention and are not intended to limit the scope of protection of the present invention.

[0035] In the present invention, the expressions “front” and “rear” with respect to the “exhaust passage” refer to the “front” and “rear” along the direction of fluid flow in the exhaust passage.

[0036] A molded case circuit breaker, as shown in FIG1-3 , includes a circuit breaker body 100 , an arc elimination device 200 , and a terminal extension plate 300 .

[0037] As shown in FIG3-5 , the circuit breaker body 100 includes a circuit breaker housing 110 , a contact system 120 , an operating mechanism 130 , an arc extinguishing system 140 , and an overload protection system.

[0038] The circuit breaker housing 110 includes a base 111 and an upper cover 112. The base 111 is provided with a first installation cavity and a first installation opening at the upper end. The circuit breaker housing 110, contact system 120, operating mechanism 130, arc extinguishing system 140, and overload protection system are all installed in the first installation cavity. The upper cover 112 is connected to the first installation opening at the upper end of the base 111.

[0039] The contact system 120 includes a moving contact 121, a static contact 122, a first conductive wiring member 123 electrically connected to the moving contact 121, and a second conductive wiring member 124 electrically connected to the static contact 122. The first conductive wiring member 123 and the second conductive wiring member 124 pass through the circuit breaker housing 110, and the outside of the circuit breaker housing 110 is respectively provided with a first wiring support seat 116 and a second wiring support seat 117 corresponding to the first conductive wiring member 123 and the second conductive wiring member 124. Specifically, the first wiring support seat 116 and the second wiring support seat 117 are arranged at both ends of the base 111, and the base 111 is provided with a first vertical partition 113 inserted between the first wiring support seat 116 and the first mounting port, and a second vertical partition 114 inserted between the second wiring support seat 117 and the first mounting port. The first conductive wiring member 123 and the second conductive wiring member 124 are installed on the first wiring support seat 116 and the second wiring support seat 117 through the first mounting port, and then the first vertical partition 113 and the second vertical partition 114 are inserted above the first conductive wiring member 123 and the second conductive wiring member 124 to separate the inside and the outside, which facilitates installation and ensures electrical safety.

[0040] The operating mechanism 130 is connected to the movable contact 121 and is used to drive the movable contact 121 to rotate, thereby opening and closing the circuit breaker with the static contact 122. The device driving the operating mechanism 130 can be a manual drive mechanism and / or an automatic drive mechanism. A common manual drive mechanism is the operating handle 131 shown in the figure, and a common automatic drive mechanism can be a drive motor triggered by a control signal.

[0041] The arc extinguishing system 140 includes an arc extinguishing hood and a plurality of arc extinguishing grids arranged in the arc extinguishing hood. The arc extinguishing hood is provided with an arc inlet end and an arc outlet end. The arc inlet end is provided corresponding to the arc breaking path of the moving contact 121 and is provided above the static contact 122. The circuit breaker housing 110 is provided with an arc discharge outlet 115 corresponding to the arc outlet end.

[0042] The overload protection system cooperates with the operating mechanism 130 to drive the operating mechanism 130 to trip freely and rotate the moving contact 121 to open the circuit when a circuit fault occurs.

[0043] The arc extinguishing device 200 is connected to the circuit breaker housing 110 and is provided with at least one exhaust duct 210. The exhaust duct 210 has an air inlet 211 and an air outlet 212. The air inlet 211 is connected to the arc discharge outlet 115 of the circuit breaker housing 110 and is used to collect gas exhausted from the circuit breaker body 100. The gas may contain arcs. The exhaust duct 210 has at least one bend 213 and at least one arc extinguishing plate 231. The air outlet 212 is connected to the outside world for exhausting gas. Gas exhausted from the circuit breaker body 100 passes through the exhaust duct 210. Due to the provision of at least one bend 213 in the exhaust duct 210, the length of the exhaust duct 210 is not limited to the size of the arc extinguishing device 200 and can be increased, which can greatly enhance the arc extinguishing effect.

[0044] Furthermore, the exhaust passage 210 includes at least one Venturi structure unit, which includes an inlet section with a flow cross-sectional area S1, a throat section with a flow cross-sectional area S2, and a diffuser section with a flow cross-sectional area S3, where S1 is greater than S2 and S3 is greater than S2. The Venturi structure unit is based on the principle of the Venturi effect, which states that at the narrowest point of the pipe of the Venturi structure unit, the dynamic pressure (velocity head) of the fluid reaches a maximum value and the static pressure (resting pressure) reaches a minimum value. The velocity of the fluid increases due to the reduction in the flow cross-sectional area. The entire flow undergoes the pipe narrowing process at the same time, so the pressure also decreases at the same time, thereby generating a pressure differential, thereby improving the flow performance of the arcing airflow in the exhaust passage.

[0045] Furthermore, the front end of the bend 213 is connected to a first transition channel and the rear end of the bend 213 is connected to a second transition channel. The flow cross-sectional area of ​​the rear end of the first transition channel is greater than or equal to the flow cross-sectional area of ​​the front end of the bend 213 to which it is connected. The flow cross-sectional area of ​​the front end of the second transition channel is greater than or equal to the flow cross-sectional area of ​​the rear end of the bend 213 to which it is connected. The first transition channel, the bend 213, and the second transition channel connected in sequence along the fluid flow direction constitute a Venturi structural unit, wherein, in the Venturi structural unit, the bend 213 constitutes a throat section with a flow cross-sectional area of ​​S2, and the first transition channel and the second transition channel constitute an inlet section and a diffusion section, respectively.

[0046] Furthermore, both the first and second transition channels are trumpet-shaped channels with a larger cross-sectional area at the front end than at the rear end. The cross-sectional area at the rear end of the first transition channel is equal to the cross-sectional area at the front end of the bend 213 to which it connects. The connecting portion of the first transition channel and the bend 213 has a smooth inner wall. This avoids creating greater resistance to airflow.

[0047] Furthermore, the exhaust passage 210 has at least two bends 213. Of the two adjacent bends 213, the second transition passage connected to the front bend 213 also forms the first transition passage connected to the rear bend 213. The cross-sectional flow area at the front end of the second transition passage is larger than the cross-sectional flow area at the rear end of the connected bend 213. This prevents the flow area of ​​the exhaust passage 210 from becoming increasingly smaller.

[0048] Furthermore, a widening groove 214 is formed at the front end of the second transition channel on one or both sides of the end of the bend 213. By setting the widening groove 214, the flow cross-sectional area at the front end of the second transition channel is suddenly increased without forming resistance to the fluid.

[0049] The arc-extinguishing plate 231 is fixed in the middle of the second transition channel, between its front and rear ends. An arc-extinguishing plate 231 is installed between adjacent bends 213, and several arc-extinguishing plates 231 are installed between the rearmost bend 213 and the gas outlet 212. This arrangement ensures that arcing is completely eliminated before gas is discharged from the gas outlet 212. Specifically, five arc-extinguishing plates 231 are installed between the rearmost bend 213 and the gas outlet 212, spaced at regular intervals.

[0050] Specifically, the arc elimination device 200 includes a cover body 240 and a channel forming block 220. As shown in Figure 9, at least one second installation cavity 241 is provided in the cover body 240 and a second installation opening is provided at the lower end thereof; the channel forming block 220 is adapted to the shape of the second installation cavity 241 and is fixed in the second installation cavity 241. A flow channel groove 221 is provided on one side or both sides of the channel forming block 220. The exhaust channel 210 is formed by the flow channel groove 221 on the side of the channel forming block 220 and the inner wall of the second installation cavity 241 or the inner wall of the second installation cavity 241 and the inner wall of the circuit breaker housing 110. The cover body 240 is respectively provided with a first opening 242 and a second opening 243 corresponding to the air inlet 211 and the air outlet 212 of the exhaust channel 210. In this embodiment, the flow channel groove 221 of the channel forming block 220 is partially exposed outside the cover 240. This portion is inserted into the circuit breaker housing 110 when the arc elimination device 200 is connected to the circuit breaker body 100. This ensures that the channel forming block 220 is not exposed outside the cover 240 and that the corresponding flow channel groove 221 mates with the inner wall of the circuit breaker housing 110. The channel forming block 220 is inserted and installed into the second installation cavity 241 through the second installation opening. A channel forming block 220 having a flow channel groove 221 of a suitable configuration can be selected as needed.

[0051] The arc-extinguishing plate 231 is fixed in the flow channel groove 221 of the channel forming block 220. Specifically, as shown in FIG11 , at least one set of arc-extinguishing plate slots 222 for inserting and installing the arc-extinguishing plate 231 is provided on both side walls of the flow channel groove 221. The arc-extinguishing plate 231 is fixed in the flow channel groove 221 by plugging.

[0052] The structure of the arc extinguishing plate 231 is shown in FIG12 , and is provided with a plurality of small holes 232 , which serve to segment and cool the arc.

[0053] As shown in Figure 4, the length of the base 111 is greater than the length of the upper cover 112, so that the circuit breaker housing 110 forms an arc discharge outlet 115 above the arc extinguishing system 140 and at the tail of the arc extinguishing system 140, and the arc extinguishing device 200 is connected above the base 111 and on the side of the upper cover 112.

[0054] The cover 240 of the arc elimination device 200 is connected and fixed to the circuit breaker housing 110 by threaded fasteners.

[0055] Specifically, the base 111 is provided with a second wiring support seat 117, one end of which protrudes relative to the upper cover 112 to form at least two first connecting plates 1111, and the second wiring support seat 117 is arranged between two adjacent first connecting plates 1111; the upper cover 112 protrudes at one end close to the second wiring support seat 117 to form at least two second connecting plates 1121, and an arc discharge outlet 115 with an L-shaped opening structure is formed between the two adjacent second connecting plates 1121. As shown in Figure 9, the cover body 240 is provided with a first connecting platform 244 for being fitted and connected to the upper end surface of the first connecting plate 1111, and a second connecting platform 245 for being fitted and connected to the upper end surface of the second connecting plate 1121. The threaded fasteners connecting the cover body 240 and the circuit breaker housing 110 are arranged between the first connecting platform 244 and the first connecting plate 1111 and between the second connecting platform 245 and the second connecting plate 1121.

[0056] The base 111 is provided with at least two second wiring support seats 117 and at least three first connecting plates 1111. A first limiting slot 1112, which is vertically arranged with a larger inner portion and a smaller outer portion, is provided on the outer wall of the first connecting plate 1111 between two adjacent second wiring support seats 117. The housing 240 is provided with a number of second mounting cavities 241, which is equal to the number of second wiring support seats 117, and a number of first connecting platforms 244, which is equal to the number of first connecting plates 1111. The second mounting cavities 241 are located between adjacent first connecting platforms 244. The first connecting platforms 244 between adjacent second mounting cavities 241 protrude downward to form a partition 246. The partition 246 is provided with a first limiting block 247 that engages with the first limiting slot 1112 for a limited position. The partition 246 separates the two adjacent wiring cavities, improving electrical safety. The first limiting block 247 engages with the first limiting slot 1112 for a limited position, facilitating installation.

[0057] The cover body 240 is provided with a first side panel 248 at the outer end of the second connecting platform 245 away from the first connecting platform 244, the lower end surface of the first side panel 248 is in contact with the upper end surface of the upper cover 112, and the lower end surface of the first side panel 248 is provided with a second limiting slot 249, and the upper end surface of the upper cover 112 is provided with a second limiting plug block 1122 which is limitedly plugged into the second limiting slot 249.

[0058] A limiting step 1113 is provided on the inner wall of the first connecting plate 1111 , and the channel forming block 220 is inserted between two adjacent first connecting plates 1111 , with its lower end abutting against the limiting step 1113 for limiting engagement.

[0059] The bottom of the air inlet 211 is positioned no lower than the upper end of the second vertical partition 114. This arrangement creates a connection space for the second conductive connector 124 between the bottom of the channel-forming block 220 and the outer wall of the second vertical partition 114. This completely separates the exhaust channel from the wiring terminals, ensuring safety.

[0060] The terminal extension plate 300 is connected to the second conductive connector 124. The outer end of the terminal extension plate 300 protrudes relative to the outer end of the arc elimination device 200, facilitating connection. Specifically, the terminal extension plate 300 is detachably connected to the second conductive connector 124 by bolts, allowing for various connection configurations as needed.

[0061] Arc extinguishing device 200 is formed by utilizing the space above and at the rear of arc extinguishing system 140, as well as by adding a certain length adjacent to second conductive connector 124. By utilizing the provision of bends 213 and implementing a reasonable spatial layout, the length of exhaust passage 210 within arc extinguishing device 200 can be significantly increased. Taking the structure shown in Figures 3 and 8 as an example, arc extinguishing device 200 occupies 40 mm of space adjacent to second conductive connector 124, and the height of the upper end of arc extinguishing device 200 is not significantly higher than the height of operating handle 131 shown in the figures. Within the limited space, the provision of six bends 213 fully utilizes this space, resulting in an exhaust passage length increased to 310 mm, equivalent to a more than sevenfold increase in passage length, a significant improvement.

[0062] The above disclosure is merely a preferred embodiment of the present invention and certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. An arc extinguishing device, comprising a housing (240), wherein at least one exhaust channel (210) is provided in the housing (240), wherein the exhaust channel (210) has an air inlet (211) and an air outlet (212), and wherein at least one arc extinguishing plate is provided in the exhaust channel (210), characterized in that: The exhaust channel (210) has at least one bend (213) between the air inlet (211) and the air outlet (212).

2. The arc elimination device according to claim 1, characterized in that: The exhaust passage (210) has at least one Venturi structural unit, the Venturi structural unit having an inlet section with a flow cross-sectional area of S1, a throat section with a flow cross-sectional area of S2, and a diffusion section with a flow cross-sectional area of S3, wherein S1 is greater than S2 and S3 is greater than S2.

3. The arc elimination device according to claim 2, characterized in that: The front end of the bend (213) is connected to a first transition channel, and the rear end of the bend (213) is connected to a second transition channel. The flow cross-sectional area of the rear end of the first transition channel is greater than or equal to the flow cross-sectional area of the front end of the bend (213) to which it is connected. The flow cross-sectional area of the front end of the second transition channel is greater than or equal to the flow cross-sectional area of the rear end of the bend (213) to which it is connected. The first transition channel, the bend (213), and the second transition channel connected in sequence along the fluid flow direction constitute a Venturi structural unit.

4. The arc elimination device according to claim 3, characterized in that: The exhaust channel (210) has at least two bends (213), and of the two adjacent bends (213), the second transition channel connected to the bend (213) located in the front also constitutes the first transition channel connected to the bend (213) located in the rear, and the flow cross-sectional area at the front end of the second transition channel is greater than the flow cross-sectional area at the rear end of the bend (213) to which it is connected, and the bend (213) is the throat section of the Venturi structural unit.

5. The arc elimination device according to claim 3, characterized in that: The first transition channel and the second transition channel are both trumpet-shaped channels with a front-end flow cross-sectional area larger than a rear-end flow cross-sectional area. The flow cross-sectional area at the rear end of the first transition channel is equal to the flow cross-sectional area at the front end of the bend (213) to which it is connected. The connecting portion between the first transition channel and the bend (213) is a smooth inner wall. The front end of the second transition channel forms a widened groove (214) on one side or both sides of the end of the bend (213).

6. The arc elimination device according to claim 2, characterized in that: The arc extinguishing plate is fixed in the middle of the second transition channel, and a plurality of arc extinguishing plates (231) are provided between the bend (213) at the rear end and the air outlet (212).

7. The arc elimination device according to claim 1, characterized in that: At least one second installation cavity (241) is provided in the cover body (240), a channel forming block (220) is fixed in the second installation cavity (241), a flow channel groove (221) is provided on one side or both sides of the channel forming block (220), and an exhaust channel (210) is formed by the flow channel groove (221) on the side of the channel forming block (220) and the inner wall of the second installation cavity (241) or the inner wall of the second installation cavity (241) and the inner wall of the circuit breaker housing (110). The cover body (240) is provided with a first opening (242) and a second opening (243) corresponding to the air inlet (211) and the air outlet (212) of the exhaust channel (210), respectively, and the arc extinguishing plate (231) is fixed in the flow channel groove (221).

8. The arc elimination device according to claim 7, characterized in that: The cover body (240) is provided with a second installation opening for inserting the channel forming block (220) into the second installation cavity (241).

9. A molded case circuit breaker, comprising a circuit breaker body (100), the circuit breaker body (100) comprising a circuit breaker housing (110) and a contact system (120), an operating mechanism (130), an arc extinguishing system (140), and an overload protection system located within the circuit breaker housing (110), the circuit breaker housing (110) being provided with an arc discharge outlet (115) at an arc outlet end corresponding to the arc extinguishing system (140), characterized in that: It also includes an arc extinguishing device (200) according to any one of claims 1 to 8, wherein the air inlet (211) of the arc extinguishing device (200) is connected to the arc discharge outlet (115) of the circuit breaker housing (110) and is used to collect gas discharged from the circuit breaker body (100).

10. The molded case circuit breaker according to claim 9, characterized in that: The circuit breaker housing (110) forms an arc discharge outlet (115) above the arc extinguishing system (140) and at the tail of the arc extinguishing system (140), and the arc extinguishing device (200) is connected above the base (111) and to the side of the upper cover (112).

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