A multi-stage pressure-reducing anti-spray arc-extinguishing exhaust passage structure and a plastic shell circuit breaker

Abstract

The application discloses a multi-stage pressure-reducing spray-resisting arc-extinguishing exhaust passage structure and a plastic shell circuit breaker, and relates to the technical field of plastic shell circuit breakers, and aims to solve the technical problem of limited arc-extinguishing effect of traditional plastic shell circuit breakers. The application comprises a bottom wrapping seat, support vertical seats arranged on the two sides of the bottom wrapping seat, a multi-stage processing cavity arranged between the two support vertical seats, and a plurality of arc-extinguishing pieces arranged in the multi-stage processing cavity. The application comprises a basic passage structure formed by the bottom wrapping seat, the support vertical seats, the multi-stage processing cavity, the arc-extinguishing pieces, lateral wrapping blocks and fastening spring pieces. The arc-extinguishing pieces are divided into fixed units away from the lateral wrapping blocks and movable units between the fixed units and the lateral wrapping blocks, so that the arc airflow is subjected to graded flow guiding and directional constraint, the insulated gate bipolar transistor chip and module are provided with arc protection, and the purposes of stably constructing multi-stage arc-extinguishing flow channels and improving the positive conduction and reverse blocking capacity of the airflow are achieved.

Description

Technical Field

[0001] This invention relates to the field of plastic-cased circuit breakers, and more specifically, to a multi-stage pressure-reducing, anti-spray, arc-extinguishing, and exhaust channel structure and a plastic-cased circuit breaker. Background Technology

[0002] Currently, molded case circuit breakers are gradually developing towards intelligence and electronic technology. They generally integrate power electronic units containing insulated gate bipolar transistor (IGBT) chips and modules to achieve rapid drive, condition monitoring and intelligent protection functions.

[0003] However, during the short-circuit breaking process of a circuit breaker, the separation of contacts generates high-temperature, high-pressure, and high-speed electric arcs and airflows, which can easily cause high-temperature ablation, electrical interference, or even damage to delicate internal power electronic components such as IGBTs. Traditional arc-extinguishing and venting structures often use simple straight-through channels, which suffer from problems such as arc backflow, airflow recirculation, and incomplete arc extinguishing, making it difficult to effectively protect the IGBT module. This affects the breaking performance and service life of the circuit breaker. In view of this, we propose a multi-stage pressure-reducing, spray-resistant arc-extinguishing and venting channel structure and a plastic-cased circuit breaker. Summary of the Invention

[0004] The purpose of this invention is to provide a multi-stage pressure-reducing, anti-jet, arc-extinguishing, and exhaust channel structure and a plastic-cased circuit breaker, so as to solve the technical problem of limited arc-extinguishing effect of traditional plastic-cased circuit breakers.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a multi-stage pressure-reducing, anti-jet, arc-extinguishing exhaust channel structure, including a bottom wrapping seat; supporting vertical seats are provided on both sides of the bottom wrapping seat; a multi-stage processing cavity is provided between the two supporting vertical seats; a plurality of arc-extinguishing plates are provided in the multi-stage processing cavity; lateral wrapping blocks are provided on the sides of the multi-stage processing cavity; wherein, the gap between two adjacent arc-extinguishing plates forms a flow guiding cavity; the flow guiding cavity is formed by a main flow channel and a plurality of branch flow channels; the branch flow channels are arranged in an alternating manner; and the branch flow channels have inclined portions and anti-backflow portions; and two adjacent arc-extinguishing plates are elastically connected by fastening springs; wherein, the flow guiding cavity has an expanded state and a reset compressed state; one of the arc-extinguishing plates relatively far from the lateral wrapping block is a fixed unit; the plurality of arc-extinguishing plates between the fixed unit and the lateral wrapping block are movable units; the multi-stage processing cavity is used to protect insulated gate bipolar transistor chips and modules from the impact of arc gas flow.

[0006] This invention constructs a basic channel structure consisting of a bottom wrapping base, a supporting vertical base, a multi-stage processing cavity, arc-extinguishing plates, lateral wrapping blocks, and fastening springs. The gaps between adjacent arc-extinguishing plates form a guiding cavity composed of a main flow channel and staggered branch flow channels, with the branch flow channels having inclined sections and anti-backflow sections. Fastening springs achieve elastic connection between adjacent arc-extinguishing plates, allowing the guiding cavity to switch between an expanded state and a retracted compressed state. By dividing the arc-extinguishing plates into fixed units away from the lateral wrapping blocks and movable units located between the fixed units and the lateral wrapping blocks, graded guidance and directional constraint of the arc airflow are achieved, providing arc protection for insulated gate bipolar transistor chips and modules, and achieving the goal of stably constructing multi-stage arc-extinguishing channels and improving the forward conduction and reverse blocking capabilities of the airflow.

[0007] Preferably, in the expanded state of the flow guide cavity, one of the movable units relatively close to the lateral wrapping block rotates, causing several arc-extinguishing plates to expand synchronously under the connection of the fastening spring, resulting in an increase in the volume of several flow guide cavities to form a micro-pressure adsorption arc stretching arc-extinguishing structure; in the repositioned and compressed state of the flow guide cavity, based on the connection of the fastening spring, several arc-extinguishing plates close synchronously, and one of the movable units relatively close to the lateral wrapping block is decoupled from the rotational force coupling; and under the elastic repositioning force of the fastening spring, the volume of several flow guide cavities is repositioned and compressed to form a unidirectional exhaust structure.

[0008] Preferably, one of the movable units relatively close to the lateral wrapping block has a traction hook protrusion at its end; the traction hook protrusion is elastically connected to the movable unit by a spring; and the side of the support stand has an arc groove to accommodate the rotation path of the traction hook protrusion.

[0009] A plastic-cased circuit breaker includes a plastic-cased circuit breaker housing; a toggle switch mechanism is disposed inside the plastic-cased circuit breaker housing; a linkage mechanism is disposed at the output end of the toggle switch mechanism; a dynamic closing shaft mechanism is disposed at the output end of the linkage mechanism; a multi-stage pressure-reducing, anti-spray, arc-extinguishing, and exhaust channel structure is disposed above the linkage mechanism; and a trigger release mechanism is disposed below the linkage mechanism; the circuit breaker integrates a power electronic unit containing an insulated-gate bipolar transistor chip and module for realizing rapid drive and protection control.

[0010] Preferably, the plastic-cased circuit breaker housing surface is provided with an exhaust channel above the flow guide cavity; the plastic-cased circuit breaker housing is also provided with a limit buckle inside.

[0011] Preferably, the dynamic closing shaft mechanism is rotatably arranged on the plastic-cased circuit breaker housing via a limiting pin; the dynamic closing shaft mechanism includes several movable opening and closing arms rotatably arranged on the limiting pin; the movable opening and closing arms are elastically connected to the limiting buckle via a torsion spring A, and the ends of the movable opening and closing arms are arranged within the multi-stage pressure reducing, spray blocking, arc extinguishing, and exhaust channel structure; a pretreatment adjusting arm is provided between two of the movable opening and closing arms; the pretreatment adjusting arm is elastically connected to the limiting buckle via a torsion spring B; several movable opening and closing arms are connected via an insulated synchronous shaft A, and the pretreatment adjusting arm is connected via an insulated synchronous shaft B, and the insulated synchronous shaft B passes through the movable opening and closing arms; wherein, the movable opening and closing arms are provided with an angle difference groove relative to the position of the insulated synchronous shaft B.

[0012] Preferably, the rotational torque of the torsion spring B driving the pretreatment adjustment arm is greater than the rotational torque of the torsion spring A driving the movable opening and closing arm; and with the cooperation of the angle difference groove, when the linkage mechanism drives the dynamic closing shaft mechanism to perform the disconnection action, the pretreatment adjustment arm and the movable opening and closing arm rotate synchronously; wherein, the rotation angle required for the pretreatment adjustment arm to drive the guide cavity to reach the fully unfolded state is less than the rotation angle required for the movable opening and closing arm to rotate from the start to the arc reaching the maximum stretching distance; so that in the initial stage when the movable opening and closing arm rotates to drive the contact to separate and generate an arc, the guide cavity completes the unfolding in advance and forms a negative pressure adsorption arc stretching arc extinguishing structure, and this negative pressure environment covers at least a part of the time period during which the arc is continuously stretched.

[0013] Preferably, the end of the pretreatment adjusting arm is provided with a Y-shaped hook groove; the hook groove is composed of a circuit breaking extrusion driven groove and a passage adaptation groove; the circuit breaking extrusion driven groove includes a basic cutting groove, a hook misalignment groove and an extrusion release groove; wherein, the basic cutting groove is used for the initial guiding connection between the pretreatment adjusting arm and the traction hook protrusion; the hook misalignment groove is used to pull the traction hook protrusion to drive the movable unit to rotate during the rotation of the pretreatment adjusting arm, so that the guide cavity is opened synchronously; a chamfer slope is provided between the hook misalignment groove and the extrusion release groove to form a temporary limiting and locking structure for the traction hook protrusion; when the pretreatment adjusting arm rotates to a predetermined angle, the traction hook protrusion slides along the chamfer slope to the extrusion release groove, and is quickly released from the pretreatment adjusting arm under the action of rotation and knocking.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention constructs a basic channel structure using a bottom wrapping base, a supporting vertical base, a multi-stage processing cavity, arc-extinguishing plates, lateral wrapping blocks, and fastening springs. The gaps between adjacent arc-extinguishing plates form a guiding cavity consisting of a main flow channel and staggered branch flow channels, with the branch flow channels having inclined sections and anti-backflow sections. Fastening springs enable elastic connection between adjacent arc-extinguishing plates, allowing the guiding cavity to switch between an expanded state and a retracted compressed state. By dividing the arc-extinguishing plates into fixed units away from the lateral wrapping blocks and movable units located between the fixed units and the lateral wrapping blocks, graded guidance and directional constraint of the arc airflow are achieved, providing arc protection for insulated gate bipolar transistor chips and modules, and achieving the goal of stably constructing multi-stage arc-extinguishing channels and improving the forward conduction and reverse blocking capabilities of the airflow.

[0015] 2. This invention utilizes a rotating unit near the lateral wrapping block, which, in conjunction with the fastening spring, drives several arc-extinguishing plates to unfold synchronously. This increases the volume of the flow-guiding cavity, which is a Tesla cavity structure, to form a micro-pressure adsorption arc stretching arc-extinguishing structure, which is beneficial for the adsorption, stretching, and cooling of the electric arc. By decoupling the rotational force coupling of the moving unit and relying on the elastic reset force of the fastening spring, the volume of the flow-guiding cavity is reset and compressed, forming a unidirectional exhaust structure. This facilitates rapid cavity closure after the electric arc is extinguished, reduces backflow of airflow and electric arc backflow, and improves the reliability of arc extinguishing and protection.

[0016] 3. The present invention provides a traction hook protrusion at the end of the movable unit near the lateral wrapping block, and the traction hook protrusion is elastically connected to the movable unit by a spring; at the same time, an arc groove adapted to the movement path of the traction hook protrusion is provided on the side of the support vertical seat, so as to achieve precise limiting and guidance of the rotation trajectory of the movable unit, which is conducive to improving the stability and synchronization of the arc extinguishing plate's unfolding and resetting action, and improving the stability and controllability of the flow channel morphology.

[0017] 4. This invention integrates the aforementioned multi-stage pressure-reducing, anti-spray, arc-extinguishing, and exhaust channel structure into the interior of a plastic-cased circuit breaker housing, forming a complete circuit breaker device in conjunction with a toggle switch mechanism, linkage mechanism, dynamic closing shaft mechanism, and trigger release mechanism; and integrates a power electronic unit containing an insulated gate bipolar transistor chip and module inside the circuit breaker to achieve coordinated operation of mechanical breaking action with intelligent drive and protection control, which is beneficial to improving the reliability of breaking action and realizing the integration of arc extinguishing and electronic component protection.

[0018] 5. This invention provides an exhaust channel above the flow guide cavity on the surface of the plastic-cased circuit breaker housing, which facilitates the safe discharge of low-temperature and low-pressure airflow after arc extinguishing and improves exhaust smoothness. By setting a limit buckle inside the plastic-cased circuit breaker housing, the invention achieves positioning and constraint of elastic moving parts, reducing the mechanical structure operation and providing limit and support.

[0019] 6. This invention assembles the dynamic closing shaft mechanism into the plastic-cased circuit breaker housing via a limiting pin, allowing the moving opening / closing arm to be elastically connected to the limiting buckle via torsion spring A, and the pretreatment adjustment arm to be elastically connected to the limiting buckle via torsion spring B. Synchronous constraints between the moving opening / closing arm and the pretreatment adjustment arm are achieved via insulated synchronous shafts A and B, and an angle difference groove is set at the position of the moving opening / closing arm corresponding to the position of the insulated synchronous shaft B, forming a motion timing difference matching structure. This facilitates the synchronous execution of the breaking action and improves the adjustability and matching degree of the arc extinguishing drive timing.

[0020] 7. This invention sets the rotational torque of torsion spring B to be greater than that of torsion spring A, and, in conjunction with the angle difference groove, enables the pretreatment adjustment arm and the moving opening and closing arm to rotate synchronously during the disconnection action. By limiting the rotation angle required for the pretreatment adjustment arm to fully expand the flow guide cavity to be less than the rotation angle required for the moving opening and closing arm to drive the arc to reach its maximum stretching distance, the flow guide cavity expands in advance at the initial stage of arc generation and forms a negative pressure adsorption structure. This allows the negative pressure environment to cover at least a portion of the arc's continuous elongation process, which is beneficial for achieving precise matching between the negative pressure sequence and the arc ignition sequence, thereby improving the arc adsorption effect and the sufficiency of arc extinguishing.

[0021] 8. This invention provides a Y-shaped hook groove at the end of the pre-treatment adjusting arm, which is divided into a circuit breaking and extrusion driven groove and a passage adaptation groove. The circuit breaking and extrusion driven groove is further subdivided into a basic cutting groove, a hooking misalignment groove, and an extrusion release groove. The basic cutting groove enables initial guiding connection, and the hooking misalignment groove enables synchronous traction and deployment of the arc extinguishing plate. A chamfered slope is set between the hooking misalignment groove and the extrusion release groove to form a temporary limiting and locking structure. When the pre-treatment adjusting arm rotates to a predetermined angle, the traction hook protrusion slides along the chamfered slope to the extrusion release groove and is quickly released under the action of rotation and tapping. This is beneficial to improving traction stability, ensuring sufficient deployment stroke, achieving instantaneous decoupling, and accelerating the reset speed of the arc extinguishing plate. Attached Figure Description

[0022] Figure 1 This is a front view schematic diagram of the plastic-cased circuit breaker of the present invention; Figure 2 This is a schematic diagram of the internal side view of the plastic-cased circuit breaker of the present invention; Figure 3 This is a schematic diagram of the three-dimensional installation structure of the dynamic closed shaft mechanism of the present invention; Figure 4 This is a three-dimensional structural diagram of the multi-stage pressure-reducing, jet-stopping, arc-extinguishing exhaust channel structure of the present invention; Figure 5 This is a three-dimensional structural diagram of the dynamic closed-loop mechanism of the present invention; Figure 6 This is a schematic diagram of the three-dimensional structure of the arc-extinguishing plate of the present invention; Figure 7This is a schematic diagram of the internal side view of the arc-extinguishing plate of the present invention; Figure 8 This is a three-dimensional structural diagram of the installation of torsion spring A and torsion spring B according to the present invention; Figure 9 This is a three-dimensional structural diagram of the pretreatment adjustment arm of the present invention; Figure 10 For the present invention Figure 9 A magnified schematic diagram of the structure at point A in the middle.

[0023] Explanation of the labels in the diagram: 1. Bottom cover; 2. Supporting vertical seat; 201. Arc groove; 3. Arc extinguishing plate; 301. Main flow channel; 302. Diverter flow channel; 303. Traction hook protrusion; 4. Lateral cover block; 5. Fastening spring; 6. Plastic-cased circuit breaker housing; 601. Exhaust channel; 602. Limit buckle; 7. Toggle switch mechanism; 8. Linkage mechanism; 9. Dynamic closing shaft mechanism; 901. Moving opening and closing arm; 9011. Angle difference groove; 902. Torsion spring A; 903. Pre-treatment adjusting arm; 9031. Hook groove; 9032. Circuit breaking compression driven groove; 9033. Pathway adapter groove; 9034. Foundation cutting groove; 9035. Hook misalignment groove; 9036. Compression release groove; 904. Torsion spring B; 10. Trigger release mechanism; 11. Fixed contact. Detailed Implementation

[0024] Example 1: As Figures 4 to 7 , Figure 9 , Figure 10As shown, the present invention relates to a multi-stage pressure-reducing, anti-jet, arc-extinguishing exhaust channel structure, including a bottom cover 1; supporting vertical seats 2 are provided on both sides of the bottom cover 1; a multi-stage processing cavity is provided between the two supporting vertical seats 2; a plurality of arc-extinguishing plates 3 are provided in the multi-stage processing cavity; lateral cover blocks 4 are provided on the sides of the multi-stage processing cavity; wherein, the gap between two adjacent arc-extinguishing plates 3 forms a flow guide cavity; the flow guide cavity is formed by a main flow channel 301 and a plurality of branch flow channels 302; the branch flow channels 302 are arranged in an alternating manner; and the branch flow channels 302 have inclined portions and anti-backflow portions; and two adjacent arc-extinguishing plates 3 are elastically connected by fastening springs 5; wherein, the flow guide cavity has an expanded state and a reset compressed state; one of the arc-extinguishing plates 3 relatively far from the lateral cover block 4 is a fixed unit; the plurality of arc-extinguishing plates 3 between the fixed unit and the lateral cover block 4 are movable units; the multi-stage processing cavity is used to protect insulated gate bipolar transistor chips and modules from the impact of arc airflow. This invention constructs a basic channel structure consisting of a bottom wrapping base 1, a supporting vertical base 2, a multi-stage processing cavity, arc-extinguishing plates 3, lateral wrapping blocks 4, and fastening springs 5. The gaps between adjacent arc-extinguishing plates 3 form a guiding cavity composed of a main flow channel 301 and staggered branch flow channels 302, with the branch flow channels 302 having inclined portions and anti-backflow portions. The fastening springs 5 ​​achieve elastic connection between adjacent arc-extinguishing plates 3, allowing the guiding cavity to switch between an expanded state and a retracted compressed state. By dividing the arc-extinguishing plates 3 into fixed units away from the lateral wrapping blocks 4 and movable units located between the fixed units and the lateral wrapping blocks 4, the invention achieves graded guidance and directional constraint of the arc airflow, providing arc protection for IGBT chips and modules, and achieving the goal of stably constructing a multi-stage arc-extinguishing channel and improving the forward conduction and reverse blocking capabilities of the airflow.

[0025] In an embodiment of the present invention, in the expanded state of the flow guide cavity, one of the movable units relatively close to the lateral wrapping block 4 rotates, and under the connection of the fastening spring sheet 5, a number of arc extinguishing plates 3 are simultaneously expanded, causing the volume of the flow guide cavity to increase and form a micro-pressure adsorption arc stretching arc extinguishing structure; in the repositioned and compressed state of the flow guide cavity, under the connection of the fastening spring sheet 5, a number of arc extinguishing plates 3 are simultaneously closed, and one of the movable units relatively close to the lateral wrapping block 4 is decoupled from the rotational motion force coupling; and under the elastic repositioning force of the fastening spring sheet 5, the volume of the flow guide cavity is repositioned and compressed to form a unidirectional exhaust structure. This invention utilizes a rotating unit near the lateral wrapping block 4, which, in conjunction with the fastening spring 5, drives several arc-extinguishing plates 3 to unfold synchronously. This increases the volume of the flow-guiding cavity, which is a Tesla cavity structure, to form a micro-pressure adsorption arc stretching arc-extinguishing structure, which is beneficial for the adsorption, stretching, and cooling of the electric arc. By decoupling the rotational force coupling of the rotating unit and relying on the elastic reset force of the fastening spring 5, the volume of the flow-guiding cavity is reset and compressed, forming a unidirectional exhaust structure. This facilitates rapid cavity closure after the electric arc is extinguished, reduces backflow of airflow and electric arc backflow, and improves the reliability of arc extinguishing and protection.

[0026] In an embodiment of the present invention, a traction hook protrusion 303 is provided at the end of one of the movable units relatively close to the lateral wrapping block 4; the traction hook protrusion 303 is elastically connected to the movable unit by a spring; an arc groove 201 is provided on the side of the supporting vertical seat 2 to accommodate the rotation path of the traction hook protrusion 303. The present invention, by providing a traction hook protrusion 303 at the end of the movable unit near the lateral wrapping block 4 and making the traction hook protrusion 303 elastically connected to the movable unit by a spring; and by providing an arc groove 201 on the side of the supporting vertical seat 2 to adapt to the movement path of the traction hook protrusion 303, achieves precise limiting and guidance of the rotation trajectory of the movable unit, which is beneficial to improving the stability and synchronization of the arc extinguishing plate 3's unfolding and resetting actions, and improving the stability and controllability of the flow channel morphology.

[0027] Example 2: As Figures 1 to 3 , Figure 5 , Figure 8 As shown, this invention relates to a plastic-cased circuit breaker, comprising a plastic-cased circuit breaker housing 6; a toggle switch mechanism 7 is disposed inside the plastic-cased circuit breaker housing 6; a linkage mechanism 8 is disposed at the output end of the toggle switch mechanism 7; a dynamic closing shaft mechanism 9 is disposed at the output end of the linkage mechanism 8; a multi-stage pressure-reducing, anti-spray, arc-extinguishing, and exhaust channel structure is disposed above the linkage mechanism 8; and a trigger release mechanism 10 is disposed below the linkage mechanism 8; the circuit breaker integrates a power electronic unit containing an insulated-gate bipolar transistor chip and module for realizing rapid drive and protection control. This invention integrates the aforementioned multi-stage pressure-reducing, anti-spray, arc-extinguishing, and exhaust channel structure inside the plastic-cased circuit breaker housing 6, forming a complete circuit breaker device in conjunction with the toggle switch mechanism 7, linkage mechanism 8, dynamic closing shaft mechanism 9, and trigger release mechanism 10; and integrates a power electronic unit containing an insulated-gate bipolar transistor (IGBT) chip and module inside the circuit breaker, realizing the coordinated operation of mechanical breaking action and intelligent drive and protection control, which is beneficial to improving the reliability of breaking action and realizing the integration of arc extinguishing and electronic component protection.

[0028] In an embodiment of the present invention, an exhaust channel 601 is provided on the surface of the plastic-cased circuit breaker housing 6 above the flow guiding cavity; a limit buckle 602 is also provided inside the plastic-cased circuit breaker housing 6. By providing the exhaust channel 601 on the surface of the plastic-cased circuit breaker housing 6 above the flow guiding cavity, the present invention facilitates the safe discharge of low-temperature, low-pressure airflow after arc extinguishing and improves exhaust smoothness; by providing the limit buckle 602 inside the plastic-cased circuit breaker housing 6, the present invention achieves positioning and constraint of elastic moving parts, reducing the mechanical structure's operating pressure and providing limitation and support.

[0029] In an embodiment of the present invention, a dynamic closing shaft mechanism 9 is rotatably arranged on the housing 6 of a plastic-cased circuit breaker via a limiting pin. The dynamic closing shaft mechanism 9 includes several movable opening and closing arms 901 rotatably arranged on the limiting pin. The movable opening and closing arms 901 are elastically connected to the limiting buckle 602 via a torsion spring A902, and the ends of the movable opening and closing arms 901 are arranged within a multi-stage pressure-reducing, anti-spray, arc-extinguishing, and exhaust channel structure. A pretreatment adjusting arm 903 is provided between two movable opening and closing arms 901. The pretreatment adjusting arm 903 is elastically connected to the limiting buckle 602 via a torsion spring B904. Several movable opening and closing arms 901 are connected via an insulated synchronous shaft A, and the pretreatment adjusting arm 903 is connected via an insulated synchronous shaft B, and the insulated synchronous shaft B passes through the movable opening and closing arms 901. An angle difference groove 9011 is provided on the movable opening and closing arms 901 relative to the position of the insulated synchronous shaft B. This invention assembles the dynamic closing shaft mechanism 9 onto the plastic-cased circuit breaker housing 6 via a limiting pin, allowing the moving opening / closing arm 901 to be elastically connected to the limiting buckle 602 via a torsion spring A902, and the pretreatment adjusting arm 903 to be elastically connected to the limiting buckle 602 via a torsion spring B904. Synchronous constraints between the moving opening / closing arm 901 and the pretreatment adjusting arm 903 are achieved via insulated synchronous shafts A and B, and an angle difference groove 9011 is provided at the position of the moving opening / closing arm 901 corresponding to the position of the insulated synchronous shaft B, forming a motion timing difference matching structure. This facilitates the synchronous execution of the breaking action and improves the adjustability and matching degree of the arc extinguishing drive timing.

[0030] In an embodiment of the present invention, the rotational torque of the torsion spring B904 driving the pretreatment adjustment arm 903 is greater than the rotational torque of the torsion spring A902 driving the moving opening and closing arm 901; and with the cooperation of the angle difference groove 9011, when the linkage mechanism 8 drives the dynamic closing shaft mechanism 9 to perform the disconnection action, the pretreatment adjustment arm 903 and the moving opening and closing arm 901 rotate synchronously; wherein, the rotation angle required for the pretreatment adjustment arm 903 to drive the guide cavity to reach the fully unfolded state is less than the rotation angle required for the moving opening and closing arm 901 to rotate from the start to the arc reaching the maximum stretching distance; so that in the initial stage when the moving opening and closing arm 901 rotates to drive the contact to separate and generate an arc, the guide cavity completes the unfolding in advance and forms a negative pressure adsorption arc stretching arc extinguishing structure, and this negative pressure environment covers at least a part of the time period during which the arc is continuously stretched. This invention sets the rotational torque of torsion spring B904 to be greater than that of torsion spring A902, and, in conjunction with the angle difference groove 9011, enables the pretreatment adjustment arm 903 and the moving opening and closing arm 901 to rotate synchronously during the disconnection action. By limiting the rotation angle required for the pretreatment adjustment arm 903 to fully expand the flow guide cavity to be less than the rotation angle required for the moving opening and closing arm 901 to drive the arc to reach its maximum stretching distance, the flow guide cavity expands in advance at the initial stage of arc generation and forms a negative pressure adsorption structure. This allows the negative pressure environment to cover at least a portion of the arc's continuous elongation process, which is beneficial for achieving precise matching between the negative pressure sequence and the arc ignition sequence, thereby improving the arc adsorption effect and the sufficiency of arc extinguishing.

[0031] In an embodiment of the present invention, the end of the pretreatment adjusting arm 903 is provided with a Y-shaped hook groove 9031; the hook groove 9031 is composed of a circuit breaking extrusion driven groove 9032 and a passage adaptation groove 9033; the circuit breaking extrusion driven groove 9032 includes a basic cutting groove 9034, a hook misalignment groove 9035 and an extrusion release groove 9036; wherein, the basic cutting groove 9034 is used for the initial guiding connection between the pretreatment adjusting arm 903 and the traction hook protrusion 303; the hook misalignment groove 9035 is used for... During the rotation of the pretreatment adjusting arm 903, the traction hook protrusion 303 drives the movable unit to rotate, causing the guide cavity to expand synchronously; a chamfered slope is provided between the hook misalignment groove 9035 and the extrusion release groove 9036, forming a temporary limiting and locking structure for the traction hook protrusion 303; when the pretreatment adjusting arm 903 rotates to a predetermined angle, the traction hook protrusion 303 slides along the chamfered slope to the extrusion release groove 9036, and quickly detaches from the pretreatment adjusting arm 903 under the action of rotation and knocking. This invention provides a Y-shaped hook groove 9031 at the end of the pre-treatment adjusting arm 903, which is divided into a circuit breaking and extrusion driven groove 9032 and a passage adaptation groove 9033. The circuit breaking and extrusion driven groove 9032 is further subdivided into a basic cutting groove 9034, a hooking misalignment groove 9035, and an extrusion release groove 9036. The basic cutting groove 9034 achieves initial guiding connection, and the hooking misalignment groove 9035 achieves synchronous traction and deployment of the arc extinguishing plate 3. A chamfered slope is provided between the hooking misalignment groove 9035 and the extrusion release groove 9036 to form a temporary limiting and locking structure. When the pre-treatment adjusting arm 903 rotates to a predetermined angle, the traction hook protrusion 303 slides along the chamfered slope to the extrusion release groove 9036 and is quickly released under the action of rotation and knocking. This helps to improve traction stability, ensure sufficient deployment stroke, achieve instantaneous decoupling, and accelerate the reset speed of the arc extinguishing plate 3.

[0032] Working principle: When the molded case circuit breaker disconnects, the operator operates the toggle switch mechanism 7, which transmits power to the dynamic closing shaft mechanism 9 via the linkage mechanism 8. This causes the dynamic closing shaft mechanism 9 to rotate around the limit pin, or it can be driven by the trigger release mechanism 10. During the disconnection process, the pre-treatment adjusting arm 903 and the moving opening and closing arm 901 rotate synchronously. Since the rotational torque of the torsion spring B904 is greater than that of the torsion spring A902, and the moving opening and closing arm 901 is provided with an angle difference groove 9011 at the position corresponding to the insulating synchronous shaft B, the pre-treatment adjusting arm 903 can form a timing difference movement with the cooperation of the angle difference groove 9011, driving the guide cavity to complete the deployment action in advance with a smaller rotation angle.

[0033] As the pretreatment adjusting arm 903 rotates, the Y-shaped hook groove 9031 at its end moves synchronously. The traction hook protrusion 303 first enters along the base cutting groove 9034, realizing the initial guiding connection between the pretreatment adjusting arm 903 and the traction hook protrusion 303. Subsequently, as the pretreatment adjusting arm 903 continues to rotate, the traction hook protrusion 303 moves along the hook misalignment groove 9035. Under the traction of the hook misalignment groove 9035, it drives the movable unit arc extinguishing plate 3 near the lateral wrapping block 4 to rotate. Under the linkage of the fastening spring plate 5, several arc extinguishing plates 3 are simultaneously deployed, thereby increasing the volume of the guiding cavity between adjacent arc extinguishing plates 3, forming a micro-pressure adsorption arc stretching arc extinguishing structure.

[0034] At this time, the rotating opening and closing arm 901 causes the contacts to separate and generate an electric arc. The guiding cavity has been pre-deployed and a negative pressure environment has been formed. This negative pressure environment can cover at least a part of the time during which the electric arc is continuously stretched, attracting the electric arc into the multi-stage processing cavity. After the electric arc enters the guiding cavity, it flows in the main flow channel 301 and several staggered branch flow channels 302. The inclined part and anti-backflow part of the branch flow channels 302 can constrain and guide the electric arc and airflow, improve the electric arc stretching, cooling and deionization effect, and at the same time reduce the impact of the electric arc and high-temperature airflow on the insulated gate bipolar transistor (IGBT) chip and module.

[0035] When the pretreatment adjusting arm 903 rotates to the predetermined angle, the traction hook protrusion 303 slides along the chamfered slope between the hook misalignment groove 9035 and the extrusion release groove 9036 to the extrusion release groove 9036, and quickly disengages from the pretreatment adjusting arm 903 under the action of rotational impact, thus releasing the rotational force coupling of the movable unit arc extinguishing plate 3. Under the elastic reset force of the fastening spring plate 5, several arc extinguishing plates 3 synchronously reset and retract, and the volume of the guide cavity is subsequently reset and compressed, forming a one-way exhaust structure to suppress arc backflow and airflow backflow. The treated low-temperature and low-pressure airflow is discharged outward through the exhaust channel 601 on the plastic-cased circuit breaker housing 6, completing the entire arc extinguishing and exhaust process.

[0036] During the overall movement, the traction hook protrusion 303 moves along the arc groove 201 on the side of the support vertical seat 2, limiting and guiding the rotation trajectory of the movable unit arc extinguishing plate 3, improving the smoothness and synchronization of the arc extinguishing plate 3's unfolding and resetting actions. The limiting buckle 602 inside the plastic-cased circuit breaker housing 6 provides limiting and support for the torsion spring A902, torsion spring B904, moving opening and closing arm 901, and pretreatment adjusting arm 903, reducing the sway and offset of the mechanical structure during operation, and ensuring that the multi-stage pressure reducing, spray-stopping, arc extinguishing, and exhaust channel structure and the plastic-cased circuit breaker maintain stable operation.

[0037] The embodiments disclosed in this invention are preferred embodiments, but are not limited thereto. Those skilled in the art can easily understand the spirit of this invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of this invention, they are all within the protection scope of this invention.

Claims

1. A multi-stage pressure-reducing, jet-blocking, arc-extinguishing exhaust channel structure, characterized in that, It includes a bottom wrapping seat (1); the bottom wrapping seat (1) is provided with supporting vertical seats (2) on both sides; a multi-stage processing cavity is provided between the two supporting vertical seats (2); a number of arc extinguishing plates (3) are provided in the multi-stage processing cavity; and a lateral wrapping block (4) is provided on the side of the multi-stage processing cavity. The gap between two adjacent arc-extinguishing plates (3) forms a flow guiding cavity; the flow guiding cavity is formed by a main flow channel (301) and several branch flow channels (302); the branch flow channels (302) are arranged in an alternating manner; and the branch flow channels (302) have an inclined part and an anti-backflow part; Furthermore, the two adjacent arc-extinguishing plates (3) are elastically connected by fastening springs (5); The flow guide cavity has an expanded state and a reset and compressed state; One of the arc-extinguishing plates (3) that is relatively far away from the lateral wrapping block (4) is a fixed unit; The arc-extinguishing plates (3) between the fixed unit and the lateral wrapping block (4) are movable units; The multi-stage processing cavity is used to protect the insulated gate bipolar transistor chip and module from the impact of electric arc airflow. In the unfolded state of the flow guide cavity, one of the movable units that is relatively close to the lateral wrapping block (4) rotates, and under the connection of the fastening spring (5), several arc extinguishing plates (3) are simultaneously unfolded, causing the volume of several flow guide cavities to increase and form a micro-pressure adsorption arc stretching arc extinguishing structure. In the resetting and compression state of the flow guide cavity, based on the connection of the fastening spring (5), several arc extinguishing plates (3) are synchronously closed, and one of the movable units that is relatively close to the lateral wrapping block (4) is released from the rotational motion force coupling; and under the elastic resetting force of the fastening spring (5), several flow guide cavity volumes are resetting and compressed to form a unidirectional exhaust structure.

2. The multi-stage pressure-reducing, jet-stopping, arc-extinguishing exhaust channel structure according to claim 1, characterized in that, One of the movable units, which is relatively close to the lateral wrapping block (4), is provided with a traction hook protrusion (303) at its end; the traction hook protrusion (303) is elastically connected to the movable unit by a spring; The side of the support vertical seat (2) is provided with an arc groove (201) to accommodate the rotation path of the traction hook protrusion (303).

3. A plastic-cased circuit breaker, characterized in that, The circuit breaker includes a plastic-cased circuit breaker housing (6); a toggle switch mechanism (7) is provided inside the plastic-cased circuit breaker housing (6); a linkage mechanism (8) is provided at the output end of the toggle switch mechanism (7); a dynamic closed shaft mechanism (9) is provided at the output end of the linkage mechanism (8); a multi-stage pressure reducing, spray blocking, arc extinguishing, and exhaust channel structure as described in claim 2 is provided above the linkage mechanism (8); and a trigger release mechanism (10) is provided below the linkage mechanism (8); the circuit breaker integrates a power electronic unit containing an insulated gate bipolar transistor chip and module for realizing fast drive and protection control.

4. The plastic-cased circuit breaker according to claim 3, characterized in that, The plastic-cased circuit breaker housing (6) has an exhaust channel (601) on its surface above the flow guide cavity; the plastic-cased circuit breaker housing (6) also has a limit buckle (602) inside.

5. The plastic-cased circuit breaker according to claim 4, characterized in that, The dynamic closing shaft mechanism (9) is rotatably arranged on the plastic-cased circuit breaker housing (6) via a limiting pin; the dynamic closing shaft mechanism (9) includes a plurality of movable opening and closing arms (901) rotatably arranged on the limiting pin; the movable opening and closing arms (901) are elastically connected to the limiting buckle (602) via a torsion spring A (902), and the ends of the movable opening and closing arms (901) are arranged in the multi-stage pressure reducing, spray blocking, arc extinguishing and exhaust channel structure; A pre-treatment adjustment arm (903) is provided between the two moving opening and closing arms (901); the pre-treatment adjustment arm (903) is elastically connected to the limit buckle (602) through a torsion spring B (904); Several of the movable opening and closing arms (901) are connected by an insulated synchronous shaft A, and the pretreatment adjustment arm (903) is connected by an insulated synchronous shaft B, and the insulated synchronous shaft B passes through the movable opening and closing arm (901). The movable opening and closing arm (901) is provided with an angle difference groove (9011) relative to the position of the insulating synchronous shaft B.

6. The plastic-cased circuit breaker according to claim 5, characterized in that, The rotational torque of the torsion spring B (904) driving the pretreatment adjustment arm (903) is greater than the rotational torque of the torsion spring A (902) driving the movable opening and closing arm (901); and with the cooperation of the angle difference groove (9011), when the linkage mechanism (8) drives the dynamic closing shaft mechanism (9) to perform the disconnection action, the pretreatment adjustment arm (903) and the movable opening and closing arm (901) rotate synchronously; wherein, the rotation angle required for the pretreatment adjustment arm (903) to drive the guide cavity to reach the fully unfolded state is less than the rotation angle required for the movable opening and closing arm (901) to rotate from the beginning to the arc reaching the maximum stretching distance; so that in the early stage when the movable opening and closing arm (901) rotates to drive the contact to separate and generate an arc, the guide cavity completes the unfolding in advance and forms a negative pressure adsorption arc stretching arc extinguishing structure, and the negative pressure environment covers at least a part of the time period during which the arc is continuously stretched.

7. The plastic-cased circuit breaker according to claim 6, characterized in that, The end of the pretreatment adjusting arm (903) is provided with a Y-shaped hook groove (9031); the hook groove (9031) is composed of a circuit breaking extrusion driven groove (9032) and a passage adaptation groove (9033); the circuit breaking extrusion driven groove (9032) includes a base cutting groove (9034), a hook misalignment groove (9035) and an extrusion release groove (9036). The connection between the circuit breaking extrusion driven groove (9032) and the passage adapter groove (9033) has a slope; The basic cutting groove (9034) is used for the initial guide connection between the pretreatment adjusting arm (903) and the traction hook protrusion (303); The hooking misalignment groove (9035) is used to pull the traction hook protrusion (303) to drive the movable unit to rotate during the rotation of the pretreatment adjusting arm (903), so that the guide cavity can be opened synchronously. A chamfered slope is provided between the hooking misalignment groove (9035) and the extrusion release groove (9036) to form a temporary limiting and locking structure for the traction hooking protrusion (303); when the pretreatment adjusting arm (903) rotates to a predetermined angle, the traction hooking protrusion (303) slides along the chamfered slope to the extrusion release groove (9036) and quickly disengages from the pretreatment adjusting arm (903) under the action of rotation and knocking.

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