A molded case circuit breaker

Abstract

The application relates to the technical field of circuit breakers, and discloses a molded case circuit breaker which comprises a shell and a shell cover, the shell and the shell cover are closed to form a placing groove, an operating mechanism and an arc extinguishing mechanism are arranged in the placing groove, an arc blocking sheet for blocking an electric arc is arranged in the placing groove, a mounting sheet is arranged in the placing groove, a static contact is arranged on the mounting sheet, a bending part is arranged on the arc blocking sheet, an arc guiding surface for guiding the electric arc is arranged on the mounting sheet, and the bending part is in abutment with the arc guiding surface. The application can limit the deformation of the arc guiding surface by the bending part, the bending part can limit the arc guiding surface, the possibility of deformation of the arc guiding surface under the action of high temperature of the electric arc is reduced, the overall structure of the arc guiding surface is more stable, the dynamic contact and the static contact can be in stable and sufficient contact, the electric arc can be effectively introduced into the arc extinguishing mechanism to be extinguished, the safety performance and the durability of the circuit breaker are further improved, and the stability and the reliability of the circuit breaker as a whole are enhanced.

Description

Technical Field

[0001] This application relates to the technical field of circuit breakers, and more particularly to a molded case circuit breaker. Background Technology

[0002] A circuit breaker is a switching device that can close, carry, and interrupt current under normal circuit conditions and close, carry, and interrupt current under abnormal circuit conditions within a specified time. It is mainly used in meter boxes, high-voltage switchgear, power grid renovation, and household electricity to protect electrical circuits and equipment.

[0003] In related technologies, circuit breakers include a housing and a cover. A placement slot is provided inside the housing, and the cover is used to seal the placement slot. An operating mechanism and an arc-extinguishing mechanism are provided inside the placement slot. The operating mechanism is used to drive the moving contact to contact the stationary contact to realize the switching of the circuit, and the arc-extinguishing mechanism is used to prevent the arc from continuing to burn.

[0004] Because the stationary contact is constantly exposed to the high temperature of the arc generated during the opening and closing of the circuit breaker, it is easily deformed by the high temperature. This may cause the position of the stationary contact to change, resulting in poor contact between the moving contact and the stationary contact during closing. This not only increases the operating resistance and affects the smoothness of the circuit breaker's closing or opening, but may also make it difficult for the arc to be effectively introduced into the arc extinguishing mechanism, thereby weakening the circuit breaker's arc extinguishing capability and reducing its reliability in interrupting fault current. Utility Model Content

[0005] To address the issue of stationary contacts easily deforming under the high temperature of an electric arc, this application provides a molded case circuit breaker.

[0006] This application provides a molded case circuit breaker, which adopts the following technical solution: A molded case circuit breaker includes a housing and a cover. The housing and cover are closed to form a placement groove. An operating mechanism and an arc-extinguishing mechanism are provided in the placement groove. The operating mechanism is used to drive a moving contact to abut a stationary contact to realize the switching of the circuit. The arc-extinguishing mechanism is used to prevent the arc from burning continuously. An arc-blocking plate is provided in the placement groove to block the arc. An mounting plate is provided in the placement groove, and the stationary contact is disposed on the mounting plate. The arc-blocking plate has a bent portion. The mounting plate has an arc-inducing surface for guiding the arc. The bent portion abuts against the arc-inducing surface, and the bent portion is used to limit the deformation of the arc-inducing surface.

[0007] By adopting the above technical solution, the bending part abuts against the arc-starting surface, which restricts the deformation of the arc-starting surface and acts as a limiter, reducing the possibility of deformation of the arc-starting surface under the high temperature of the electric arc. This makes the overall structure of the arc-starting surface more stable, thereby ensuring that the moving contact and the stationary contact can make stable and sufficient contact, so that the electric arc can be effectively introduced into the arc-extinguishing mechanism for extinguishing, further improving the safety performance and durability of the circuit breaker, and thus enhancing the overall stability and reliability of the circuit breaker.

[0008] Optionally, an electromagnetic coil mechanism is provided in the placement slot, and the arc-blocking plate is located between the arc-extinguishing mechanism and the electromagnetic coil mechanism, with the height of the arc-blocking plate being higher than the height of the electromagnetic coil mechanism.

[0009] By adopting the above technical solution, the height of the arc-blocking plate is higher than that of the electromagnetic coil mechanism, enabling the arc-blocking plate to block the electric arc generated during the arc extinguishing process and prevent it from spreading or interfering with the electromagnetic coil area. The higher arc-blocking plate can form a physical barrier in space, limiting the propagation path of the electric arc, thereby protecting the electromagnetic coil mechanism, reducing the damage to the electromagnetic coil mechanism from high temperature and electric arc force, helping to maintain the electromagnetic performance of the electromagnetic coil mechanism, and improving the stability of the equipment.

[0010] Optionally, the placement slot is provided with multiple locking blocks, and the multiple locking blocks form a slot for placing the arc extinguishing mechanism.

[0011] By adopting the above technical solution, multiple card blocks form a slot for placing the arc extinguishing mechanism, which enables the slot to position the arc extinguishing mechanism. The card blocks can restrict the movement of the arc extinguishing mechanism to avoid the impact of the electric arc blowing the arc extinguishing mechanism at an angle, so that the arc extinguishing mechanism can be stably located in the slot, allowing the electric arc to stably enter the arc extinguishing mechanism to achieve extinguishing.

[0012] Optionally, the arc extinguishing mechanism includes an arc extinguishing cover and multiple arc extinguishing plates. The arc extinguishing cover has a receiving groove, and the multiple arc extinguishing plates are all located in the receiving groove. The side of the arc extinguishing cover has a receiving groove, and the receiving groove is connected to the receiving groove.

[0013] By adopting the above technical solution, a receiving groove is provided on the side of the arc extinguishing cover, and the receiving groove is connected to the receiving groove, so that the staff can take the arc extinguishing mechanism through the receiving groove. The staff can determine the correct direction of the arc extinguishing mechanism by touch and sight, reducing the occurrence of the staff installing the arc extinguishing cover backwards.

[0014] Optionally, the arc-extinguishing plate is provided with a flow-guiding slope, and the distance from the flow-guiding slope to the axis of the receiving tank gradually decreases along the direction in which the gas enters the arc-extinguishing hood. The flow-guiding slope is used to guide the gas through the arc-extinguishing hood to achieve cooling.

[0015] By adopting the above technical solution, the distance from the guide slope to the axis of the receiving tank gradually decreases along the direction of gas entering the arc extinguishing chamber, so that the backflow slope can guide the gas into the arc extinguishing chamber to cool the arc extinguishing chamber, prevent the arc extinguishing chamber temperature from being too high and affecting the arc extinguishing ability of the arc extinguishing plate, thereby enhancing the stability of the arc extinguishing mechanism.

[0016] Optionally, the placement groove is provided with a first snap-fit ​​groove for inserting the arc-blocking piece, and the first snap-fit ​​groove is provided with a first limiting post, which is used to limit the deformation of the bent part in a direction away from the arc-inducing surface.

[0017] By adopting the above technical solution, the first limiting post is used to limit the deformation of the bent part away from the arc-initiating surface, so that the first limiting post can block the arc-initiating surface, reducing the possibility of the bent part shifting position due to the high temperature of the electric arc, thereby enhancing the stability of the equipment.

[0018] Optionally, the arc-blocking plate is detachably connected to the cover, and the cover has a second locking groove for inserting the arc-blocking plate. The groove wall of the second locking groove is provided with an elastic protrusion, which is used to prevent the arc-blocking plate from disengaging from the second locking groove.

[0019] By adopting the above technical solution, the cover has a second snap-fit ​​groove for inserting the arc-blocking plate. The operator can first install the arc-blocking plate on the cover and fix its position with the protrusion. This facilitates the operator's installation of the arc-blocking plate, reduces interference from other components in the groove, and provides convenience for the operator's installation process.

[0020] Optionally, the second locking groove has a second limiting post on its groove wall, and the cover has a baffle that abuts against the arc-blocking plate. The baffle is used to drive the arc-blocking plate to move toward the second limiting post.

[0021] By adopting the above technical solution, the baffle drives the arc-blocking piece to move towards the second limiting post, so that the baffle can limit the arc-blocking piece, reduce the possibility of the arc-blocking piece moving, and thus allow the arc-blocking piece to be accurately aligned with the first locking groove, making it easier for the staff to install the arc-blocking piece.

[0022] In summary, this application includes at least one of the following beneficial technical effects: 1. By abutting against the arc-starting surface, the bending part restricts the deformation of the arc-starting surface and acts as a limiter, reducing the possibility of deformation under the high temperature of the electric arc. This makes the overall structure of the arc-starting surface more stable, ensuring stable and sufficient contact between the moving and stationary contacts. This allows the electric arc to be effectively introduced into the arc-extinguishing mechanism for extinguishing, further improving the safety performance and durability of the circuit breaker, thereby enhancing the overall stability and reliability of the circuit breaker.

[0023] 2. By making the arc-blocking plate higher than the height of the electromagnetic coil mechanism, the arc-blocking plate can block the electric arc generated during the arc extinguishing process, preventing it from spreading or interfering with the electromagnetic coil area. The higher arc-blocking plate can form a physical barrier in space, limiting the propagation path of the electric arc, thereby protecting the electromagnetic coil mechanism, reducing the damage to the electromagnetic coil mechanism from high temperature and electric arc force, helping to maintain the electromagnetic performance of the electromagnetic coil mechanism, and improving the stability of the equipment. Attached Figure Description

[0024] Figure 1 This is a structural schematic diagram of an embodiment of this application; Figure 2 This is a partial structural schematic diagram highlighting the arc guide plate in an embodiment of this application; Figure 3 This is a partially exploded view of the first card slot in the embodiments of this application; Figure 4 This is a partial structural schematic diagram highlighting the arc-extinguishing mechanism in an embodiment of this application; Figure 5 This is a partial structural diagram highlighting the shell cover in an embodiment of this application.

[0025] Reference numerals: 1. Shell; 11. Placement slot; 111. Operating mechanism; 112. Electromagnetic coil mechanism; 12. Arc-blocking plate; 121. Bending part; 122. Protrusion block; 13. Mounting plate; 131. Arc-initiating surface; 14. Locking block; 141. Locking groove; 15. Arc-guided plate; 151. Arc-guided channel; 16. Exhaust channel; 17. Groove; 171. Long contact piece; 172. Positioning piece; 18. First locking groove; 181. First limiting post; 2. Shell cover; 21. Positioning groove; 22. Second locking groove; 221. Second limiting post; 222. Protrusion; 23. Baffle; 3. Arc-extinguishing mechanism; 31. Arc-extinguishing cover; 311. Receiving groove; 312. Receiving groove; 313. Vent hole; 32. Arc-extinguishing plate; 321. Arc-extinguishing channel; 322. Flow guide groove; 323. Flow guide slope. Detailed Implementation

[0026] The following is in conjunction with the appendix Figures 1-5 This application will be described in further detail.

[0027] This embodiment discloses a molded case circuit breaker. (Refer to...) Figure 1 and Figure 2 A molded case circuit breaker includes a housing 1 and a cover 2. The housing 1 and cover 2 are closed to form a placement groove 11. Both the housing 1 and cover 2 are provided with mutually cooperating limiting structures to limit the position of components inside the placement groove 11. An operating mechanism 111, an electromagnetic coil mechanism 112, and an arc-extinguishing mechanism 3 are fixedly connected inside the placement groove 11. The operating mechanism 111 is used to drive the moving contact to contact the stationary contact to realize the circuit switching. The electromagnetic coil mechanism 112 is used to provide short-circuit protection for the circuit. The arc-extinguishing mechanism 3 is used to prevent the arc from continuing to burn.

[0028] Reference Figure 2 An arc-blocking plate 12 is detachably connected within the placement slot 11 to block the electric arc. The arc-blocking plate 12 is conductive and made of iron, with copper plated on its outer surface to reduce the possibility of rusting. The arc-blocking plate 12 is located between the arc-extinguishing mechanism 3 and the electromagnetic coil mechanism 112. The height of the arc-blocking plate 12 is greater than the height of the housing 1. The arc-blocking plate 12 can prevent the electric arc in the arc-extinguishing mechanism 3 from spreading to the electromagnetic coil mechanism 112, thereby reducing the possibility of the electric arc interfering with the electromagnetic coil mechanism 112.

[0029] Reference Figure 3 A mounting plate 13 is fixedly connected within the placement groove 11, and the stationary contact is fixedly connected to the outer surface of the mounting plate 13. A curved portion 121 is integrally formed on the arc-blocking plate 12, and an arc-initiating surface 131 for guiding the electric arc is integrally formed on the mounting plate 13. The curved portion 121 abuts against the arc-initiating surface 131, thereby limiting the deformation of the arc-initiating surface 131 and protecting the stationary contact, reducing the possibility of displacement or thermal melting damage to the stationary contact under the high-temperature impact of the electric arc. A protrusion 122 is fixedly connected to the surface of the curved portion 121 near the arc-initiating surface 131. The protrusion 122 abuts against the arc-initiating surface 131 to limit the movement of the arc-blocking plate 12, reducing the possibility of movement of the arc-blocking plate 12.

[0030] Reference Figure 2 and Figure 3 Multiple locking blocks 14 are fixedly connected to the bottom wall of the placement slot 11. The multiple locking blocks 14 are arranged around the arc extinguishing mechanism 3, and a locking groove 141 for placing the arc extinguishing mechanism 3 is formed between the multiple locking blocks 14. The positioning of the arc extinguishing mechanism 3 by the locking blocks 14 prevents the impact generated by the electric arc from blowing the arc extinguishing mechanism 3 at an angle.

[0031] Reference Figure 2 and Figure 4The arc-extinguishing mechanism 3 includes an arc-extinguishing cover 31 and multiple arc-extinguishing plates 32. The arc-extinguishing cover 31 has a receiving groove 311 for placing the multiple arc-extinguishing plates 32. The opposite sides of the arc-extinguishing cover 31 have receiving grooves 312 communicating with the receiving groove 311. The back of the arc-extinguishing cover 31 has multiple air vents 313. The multiple arc-extinguishing plates 32 are arranged in an array along the length of the receiving groove 311, and an arc-extinguishing channel 321 is formed between two adjacent arc-extinguishing plates 32.

[0032] Reference Figure 2 and Figure 5 Multiple arc guide plates 15 are integrally formed on both the shell 1 and the shell cover 2. An arc guide channel 151 communicating with the arc extinguishing channel 321 is formed between two adjacent arc guide plates 15. The electric arc can enter the arc extinguishing channel 321 through the arc guide channel 151 and then be discharged from the shell 1 through the vent 313.

[0033] Reference Figure 2 and Figure 5 A guide groove 322 is formed on the surface of the arc-extinguishing plate 32 away from the bottom wall of the receiving tank 311. Guide slopes 323 are formed on both opposite sides of the guide groove 322. The distance from the guide slope 323 to the axis of the guide groove 322 gradually decreases along the direction of gas entry into the arc-extinguishing shroud 31. The guide slope 323 guides the gas into the arc-extinguishing shroud 31, thereby cooling the gas inside the arc-extinguishing shroud 31 before it flows out from the outlet 313. A corresponding exhaust channel 16 is formed in the placement tank 11, through which hot gas can be discharged from the shell 1.

[0034] Reference Figure 2 and Figure 5 The placement groove 11 has a groove 17, and a long contact piece 171 is fixedly connected in the groove 17. A positioning piece 172 is integrally formed on the surface of the long contact piece 171 away from the bottom wall of the placement groove 11. The cover 2 has a positioning groove 21 for the positioning piece 172 to be inserted. When the cover 2 is installed on the housing 1, the long contact piece 171 is positioned by inserting it into the positioning groove 21.

[0035] Reference Figure 3 The bottom wall of the placement groove 11 is provided with a first snap-fit ​​groove 18 for inserting the arc-blocking piece 12. A first limiting post 181 is integrally formed on the groove wall of the first snap-fit ​​groove 18 near the bending part 121. The first limiting post 181 is used to limit the bending part 121 from deforming in a direction away from the arc-inducing surface 131, and further strengthen the restriction of the bending part 121 on the arc-inducing surface 131.

[0036] Reference Figure 3 and Figure 5The arc-blocking plate 12 is detachably connected to the cover 2. The cover 2 has a second locking groove 22 for inserting the arc-blocking plate 12. A second limiting post 221 for limiting the deformation of the bending part 121 is integrally formed on the groove wall of the second locking groove 22. An elastic protrusion 222 is fixedly connected to the groove wall of the second locking groove 22. The protrusion 222 can prevent the arc-blocking plate 12 from disengaging from the second locking groove 22.

[0037] Reference Figure 3 and Figure 5 A baffle 23 is fixedly connected to the cover 2. The baffle 23 is used to drive the arc-blocking piece 12 to move toward the second limiting post 221. When the arc-blocking piece 12 abuts against the groove wall of the second locking groove 22 away from the second limiting post 221, the bent part 121 is located between the baffle 23 and the second limiting post 221, and the arc-blocking piece 12 is positioned at this time.

[0038] The implementation principle of a molded case circuit breaker according to an embodiment of this application is as follows: When the operating mechanism 111 drives the moving contact to abut the stationary contact on the mounting plate 13, the circuit is closed, generating an electric arc. The electric arc enters the arc extinguishing channel 321 through the arc guiding channel 151 to be extinguished, and then enters the exhaust channel 16 through the vent hole 313 to be discharged from the housing 1. Since the arc-blocking plate 12 is small in size and there are many components arranged inside the housing 1, in order to facilitate the installation of the arc-blocking plate 12 by the operator, the operator first inserts the arc-blocking plate 12 into the second locking groove 22 of the housing cover 2. At this time, the protrusion 222 deforms, which can prevent the arc-blocking plate 12 from disengaging from the second locking groove 22. The bending part 121 is located between the baffle 23 and the second limiting post 221, realizing the positioning of the arc-blocking plate 12, so that the arc-blocking plate 12 can be accurately inserted into the first locking groove 18.

[0039] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," "third," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms "an" or "a" and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms "comprising" or "including" and similar terms mean that the elements or objects preceding "comprising" or "including" encompass the elements or objects listed following "comprising" or "including" and their equivalents, and do not exclude other elements or objects. "Above," "below," "left," "right," etc., are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0040] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the design concept of this application should be included within the protection scope of this application.

Claims

1. A molded case circuit breaker, comprising a housing (1) and a cover (2), wherein the housing (1) and the cover (2) are closed to form a placement groove (11), wherein the placement groove (11) is provided with an operating mechanism (111) and an arc-extinguishing mechanism (3), wherein the operating mechanism (111) is used to drive a moving contact to abut a stationary contact to realize the switching of the circuit, and the arc-extinguishing mechanism (3) is used to prevent the arc from continuing to burn, characterized in that: The placement groove (11) is provided with an arc-blocking plate (12) for blocking electric arcs. The placement groove (11) is provided with an mounting plate (13). The stationary contact is set on the mounting plate (13). The arc-blocking plate (12) is provided with a bent portion (121). The mounting plate (13) is provided with an arc-guiding surface (131) for guiding electric arcs. The bent portion (121) abuts against the arc-guiding surface (131). The bent portion (121) is used to limit the deformation of the arc-guiding surface (131).

2. A molded case circuit breaker according to claim 1, characterized in that: The placement slot (11) is provided with an electromagnetic coil mechanism (112), and the arc-blocking plate (12) is located between the arc-extinguishing mechanism (3) and the electromagnetic coil mechanism (112). The height of the arc-blocking plate (12) is higher than the height of the electromagnetic coil mechanism (112).

3. A molded case circuit breaker according to claim 1, characterized in that: The placement slot (11) is provided with a plurality of locking blocks (14), and the plurality of locking blocks (14) form a slot (141) for placing the arc extinguishing mechanism (3).

4. A molded case circuit breaker according to claim 1, characterized in that: The arc extinguishing mechanism (3) includes an arc extinguishing cover (31) and multiple arc extinguishing plates (32). The arc extinguishing cover (31) has a receiving groove (311) and the multiple arc extinguishing plates (32) are located in the receiving groove (311). The side of the arc extinguishing cover (31) has a receiving groove (312) and the receiving groove (312) is connected to the receiving groove (311).

5. A molded case circuit breaker according to claim 4, characterized in that: The arc-extinguishing plate (32) is provided with a flow-guiding inclined surface (323). The distance from the flow-guiding inclined surface (323) to the axis of the receiving groove (311) gradually decreases along the direction of gas entering the arc-extinguishing hood (31). The flow-guiding inclined surface (323) is used to guide the gas through the arc-extinguishing hood (31) to achieve cooling.

6. A molded case circuit breaker according to claim 1, characterized in that: The placement groove (11) is provided with a first snap-fit ​​groove (18) for inserting the arc-blocking piece (12). The first snap-fit ​​groove (18) is provided with a first limiting post (181). The first limiting post (181) is used to limit the deformation of the bent part (121) in a direction away from the arc-inducing surface (131).

7. A molded case circuit breaker according to claim 1, characterized in that: The arc-blocking plate (12) is detachably connected to the cover (2). The cover (2) has a second snap-fit ​​groove (22) for inserting the arc-blocking plate (12). The groove wall of the second snap-fit ​​groove (22) is provided with an elastic protrusion (222). The protrusion (222) is used to restrict the arc-blocking plate (12) from disengaging from the second snap-fit ​​groove (22).

8. A molded case circuit breaker according to claim 7, characterized in that: The second snap-fit ​​groove (22) has a second limiting post (221) on its groove wall, and the cover (2) has a baffle (23) that abuts against the arc-blocking piece (12). The baffle (23) is used to drive the arc-blocking piece (12) to move toward the second limiting post (221).

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