Arc extinguish chamber movable part assembly, arc extinguish chamber and circuit breaker

Abstract

The invention provides an arc extinguish chamber movable part assembly, an arc extinguish chamber and a circuit breaker, and belongs to the technical field of switch equipment. The arc extinguish chamber movable part assembly comprises a movable main contact and a nozzle, the movable main contact comprises a main body part and a head part which are connected in a matched mode through a thread structure, an annular blocking part is arranged in an inner hole of the main body part, the nozzle comprises an annular protrusion, and the end face of one axial side of the annular protrusion is used for being located and blocked with the annular blocking part. The head part is provided with a pressing part used for pressing the end face of the other axial side of the annular protrusion, and the pressing part is used for being matched with the annular stopping part to jointly clamp the annular protrusion of the nozzle when the head part and the main body part are connected in a threaded fit mode. The nozzle can be prevented from loosening by clamping the annular protrusion at the two axial ends, the sealing performance of the contact portion of the annular protrusion and the annular stop portion is guaranteed, and it is guaranteed that the arc extinguishing effect of the nozzle is not affected.

Description

Technical Field

[0001] This invention relates to an assembly of a movable part of an arc-extinguishing chamber, an arc-extinguishing chamber and a circuit breaker, belonging to the field of switchgear technology. Background Technology

[0002] The movable part assembly of a circuit breaker arc-extinguishing chamber typically includes the moving main contact, nozzle, moving arc contact, and operating lever. Usually, the moving main contact and nozzle are fixedly connected with screws, as are the operating lever, moving arc contact, and moving main contact. The presence of screws increases the weight of the movable part assembly, hindering the lightweight design of the arc-extinguishing chamber. Furthermore, the movable part assembly requires more operating power during the breaking process, which affects the breaking speed to some extent. At the same time, the screw assembly process is relatively complex and inconvenient to operate.

[0003] In response, Chinese utility model patent CN219916948U discloses a moving contact assembly. The moving contact assembly includes a moving main contact and a nozzle fixedly connected to the moving main contact. The moving main contact includes an aluminum variable-diameter cylindrical body, which comprises a large-diameter section and a small-diameter section with separate designs. An inwardly extending annular stop is provided at the end of the large-diameter section facing the small-diameter section. The large-diameter section and the small-diameter section together form an annular mounting groove. The moving main contact also includes an arc-resistant ring fixed within the annular mounting groove. The arc-resistant ring is made of copper or a copper-tungsten alloy. In one embodiment, the annular stop has an axially extending section extending towards the small-diameter section. Both the inner and outer surfaces of the axially extending section are threaded. The small-diameter section is threaded to the external thread of the axially extending section to clamp and fix the arc-resistant ring. An annular protrusion on the nozzle is threaded to the internal thread of the axially extending section. During installation, the annular stop can position and stop the annular protrusion, facilitating nozzle installation.

[0004] The above embodiment eliminates the use of screws, reducing the weight of moving parts and facilitating assembly. The main function of the small-diameter section (the head of the moving main contact) is to clamp the arc-extinguishing ring in conjunction with the large-diameter section (the main body of the moving main contact). However, during installation, the nozzle is only positioned and stopped by one axial end face of the annular protrusion and the annular stop on the main body. A gap remains between the other axial end face of the annular protrusion and the head, which poses a risk of loosening during use. This compromises the sealing of the contact area between the annular protrusion and the annular stop, affecting the nozzle's arc-extinguishing effect. Furthermore, the moving main contact in the above embodiment comprises three parts: the main body, the head, and the arc-extinguishing ring. This results in a large number of components, a complex structure, high manufacturing costs, and cumbersome assembly. Summary of the Invention

[0005] The purpose of this invention is to provide a movable part assembly for an arc-extinguishing chamber, so as to solve the problem that in the prior art, the nozzle is only positioned and stopped by one side end face of the annular protrusion and the annular stop on the main body, which leads to the risk of nozzle loosening and the inability to guarantee the sealing of the contact part between the annular protrusion and the annular stop, thus affecting the arc-extinguishing effect of the nozzle; the purpose of this invention is also to provide an arc-extinguishing chamber and a circuit breaker to solve the above problems.

[0006] To achieve the above objectives, the assembly of the movable part of the arc-extinguishing chamber in this invention adopts the following technical solution: An arc-extinguishing chamber movable part assembly includes a moving main contact and a nozzle. The moving main contact includes a main body and a head connected by a threaded structure. An annular stop is provided in the inner hole of the main body. The nozzle includes an annular protrusion. One axial end face of the annular protrusion is used to position and stop with the annular stop. The head has a clamping part for pressing the other axial end face of the annular protrusion. The clamping part is used to cooperate with the annular stop to clamp the annular protrusion of the nozzle when the head and the main body are threadedly connected.

[0007] The beneficial effects of the above technical solution are as follows: This invention proposes an improved assembly of the movable part of the arc-extinguishing chamber. The improvement lies in that the head of the moving main contact has a clamping part for clamping the other end face of the annular protrusion in the axial direction. The clamping part is used to cooperate with the annular stop part to clamp the annular protrusion of the nozzle when the head of the moving main contact and the main body are threadedly connected. By clamping the annular protrusion at both ends in the axial direction, the nozzle can be prevented from loosening, thereby ensuring the sealing of the contact part between the annular protrusion and the annular stop part, and ensuring that the arc-extinguishing effect of the nozzle is not affected.

[0008] Furthermore, the clamping part extends into the inner hole of the main body, the opening of the inner hole of the main body is provided with an internal thread, and the clamping part is provided with an external thread. The clamping part is connected to the inner hole of the main body through the external thread.

[0009] Furthermore, the head is made of an ablation-resistant material, and the head also includes a stop part that is connected to the clamping part and cooperates with the end face stop of the main body part, with the outer peripheral surface of the stop part being aligned with the outer peripheral surface of the main body part.

[0010] Furthermore, the clamping part has an L-shaped cross-section and includes a long section and a short section connected vertically. The long section is provided with the aforementioned external thread, and the short section is provided with an anti-rotation groove for engaging with a turning tool to prevent rotation.

[0011] Furthermore, the outer peripheral surface of the annular protrusion and the inner wall surface of the main body are in a smooth fit. A first elastic element is provided between the annular protrusion and the annular stop. A stop step is provided at the end of the internal thread in the inner hole of the main body. The pressing part simultaneously presses the stop step and the other side end face of the annular protrusion along the axial direction.

[0012] Furthermore, the movable part assembly of the arc-extinguishing chamber also includes a moving arc contact and an operating rod. A partition for forming a thermal expansion chamber is provided inside the main body. The moving arc contact is located inside the thermal expansion chamber and its end abuts against the partition. The end of the operating rod passes through the partition and is threadedly connected to the moving arc contact.

[0013] Furthermore, a second elastic element is provided between the moving arc contact and the partition.

[0014] Furthermore, a groove is provided on the side end face of the partition facing away from the moving arc contact, and a boss is provided on the outer periphery of the operating rod. The boss is embedded in the groove and presses against the bottom wall of the groove.

[0015] To achieve the above objectives, the arc-extinguishing chamber in this invention adopts the following technical solution: An arc-extinguishing chamber includes a housing and a movable assembly disposed within the housing. The movable assembly includes a moving main contact and a nozzle. The moving main contact includes a main body and a head connected by a threaded structure. An annular stop is provided in the inner hole of the main body. The nozzle includes an annular protrusion. One axial end face of the annular protrusion is used to position and stop with the annular stop. The head has a clamping part for pressing the other axial end face of the annular protrusion. The clamping part is used to cooperate with the annular stop to clamp the annular protrusion of the nozzle when the head and the main body are threadedly connected.

[0016] The beneficial effects of the above technical solution are as follows: The present invention proposes an improved arc-extinguishing chamber. The improvement lies in that the head of the moving main contact in the movable part assembly has a clamping part for clamping the other end face of the annular protrusion in the axial direction. The clamping part is used to cooperate with the annular stop part to clamp the annular protrusion of the nozzle when the head of the moving main contact and the main body are threadedly connected. By clamping the annular protrusion at both ends in the axial direction, the nozzle can be prevented from loosening, thereby ensuring the sealing of the contact part between the annular protrusion and the annular stop part, and ensuring that the arc-extinguishing effect of the nozzle is not affected.

[0017] Furthermore, the clamping part extends into the inner hole of the main body, the opening of the inner hole of the main body is provided with an internal thread, and the clamping part is provided with an external thread. The clamping part is connected to the inner hole of the main body through the external thread.

[0018] Furthermore, the head is made of an ablation-resistant material, and the head also includes a stop part that is connected to the clamping part and cooperates with the end face stop of the main body part, with the outer peripheral surface of the stop part being aligned with the outer peripheral surface of the main body part.

[0019] Furthermore, the clamping part has an L-shaped cross-section and includes a long section and a short section connected vertically. The long section is provided with the aforementioned external thread, and the short section is provided with an anti-rotation groove for engaging with a turning tool to prevent rotation.

[0020] Furthermore, the outer peripheral surface of the annular protrusion and the inner wall surface of the main body are in a smooth fit. A first elastic element is provided between the annular protrusion and the annular stop. A stop step is provided at the end of the internal thread in the inner hole of the main body. The pressing part simultaneously presses the stop step and the other side end face of the annular protrusion along the axial direction.

[0021] Furthermore, the movable part assembly also includes a moving arc contact and an operating rod. A partition for forming a thermal expansion chamber is provided inside the main body. The moving arc contact is located inside the thermal expansion chamber and its end abuts against the partition. The end of the operating rod passes through the partition and is threadedly connected to the moving arc contact.

[0022] Furthermore, a second elastic element is provided between the moving arc contact and the partition.

[0023] Furthermore, a groove is provided on the side end face of the partition facing away from the moving arc contact, and a boss is provided on the outer periphery of the operating rod. The boss is embedded in the groove and presses against the bottom wall of the groove.

[0024] To achieve the above objectives, the circuit breaker in this invention adopts the following technical solution: A circuit breaker includes an arc-extinguishing chamber and an operating mechanism. The arc-extinguishing chamber includes a housing and a movable part assembly disposed within the housing. The movable part assembly includes a moving main contact and a nozzle. The moving main contact includes a main body and a head connected by a threaded structure. An annular stop is provided in the inner hole of the main body. The nozzle includes an annular protrusion. One axial end face of the annular protrusion is used to position and stop with the annular stop. The head has a clamping part for pressing the other axial end face of the annular protrusion. The clamping part is used to cooperate with the annular stop to clamp the annular protrusion of the nozzle when the head and the main body are threadedly connected.

[0025] The beneficial effects of the above technical solution are as follows: This invention proposes an improved circuit breaker. The improvement lies in that the head of the moving main contact in the assembly of the arc-extinguishing chamber has a clamping part for clamping the other end face of the annular protrusion in the axial direction. The clamping part is used to cooperate with the annular stop part to clamp the annular protrusion of the nozzle when the head of the moving main contact and the main body are threadedly connected. By clamping the annular protrusion at both ends in the axial direction, the nozzle can be prevented from loosening, thereby ensuring the sealing of the contact part between the annular protrusion and the annular stop part, and ensuring that the arc-extinguishing effect of the nozzle is not affected.

[0026] Furthermore, the clamping part extends into the inner hole of the main body, the opening of the inner hole of the main body is provided with an internal thread, and the clamping part is provided with an external thread. The clamping part is connected to the inner hole of the main body through the external thread.

[0027] Furthermore, the head is made of an ablation-resistant material, and the head also includes a stop part that is connected to the clamping part and cooperates with the end face stop of the main body part, with the outer peripheral surface of the stop part being aligned with the outer peripheral surface of the main body part.

[0028] Furthermore, the clamping part has an L-shaped cross-section and includes a long section and a short section connected vertically. The long section is provided with the aforementioned external thread, and the short section is provided with an anti-rotation groove for engaging with a turning tool to prevent rotation.

[0029] Furthermore, the outer peripheral surface of the annular protrusion and the inner wall surface of the main body are in a smooth fit. A first elastic element is provided between the annular protrusion and the annular stop. A stop step is provided at the end of the internal thread in the inner hole of the main body. The pressing part simultaneously presses the stop step and the other side end face of the annular protrusion along the axial direction.

[0030] Furthermore, the movable part assembly also includes a moving arc contact and an operating rod. A partition for forming a thermal expansion chamber is provided inside the main body. The moving arc contact is located inside the thermal expansion chamber and its end abuts against the partition. The end of the operating rod passes through the partition and is threadedly connected to the moving arc contact.

[0031] Furthermore, a second elastic element is provided between the moving arc contact and the partition.

[0032] Furthermore, a groove is provided on the side end face of the partition facing away from the moving arc contact, and a boss is provided on the outer periphery of the operating rod. The boss is embedded in the groove and presses against the bottom wall of the groove. Attached Figure Description

[0033] Figure 1 This is a structural diagram of an embodiment of the movable part assembly of the arc-extinguishing chamber of the present invention; Figure 2 for Figure 1 A magnified view of a portion of the image; Figure 3 for Figure 1 Structural diagram of the mid-head; Figure 4 for Figure 1 Partial structural diagram of the main body; In the figure: 1. Nozzle; 11. Annular protrusion; 2. Head; 21. Pressing part; 211. External thread; 212. Anti-rotation groove; 22. Stop part; 221. Stop surface; 3. Main body; 31. Annular stop part; 32. Stop step; 33. Internal thread; 34. Partition; 4. Moving arc contact; 5. Operating rod; 51. Screw; 52. Boss; 6. First elastic element; 7. Second elastic element. Detailed Implementation

[0034] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0035] To address the technical problems existing in the prior art, the basic technical concept of the present invention is to provide a pressing part at the head of the moving main contact. The pressing part is used to press the other side end face of the annular protrusion on the nozzle axially when the head and the main body are threadedly connected, thereby cooperating with the annular stop part in the main body to clamp the annular protrusion of the nozzle and prevent the nozzle from loosening.

[0036] An embodiment of the assembly of the movable part of the arc-extinguishing chamber in this invention: like Figure 1 As shown, the movable part assembly of the arc-extinguishing chamber includes a nozzle 1, a moving main contact composed of a head 2 and a main body 3, a moving arc contact 4, and an operating lever 5.

[0037] like Figure 2 As shown, the nozzle 1 is provided with an annular protrusion 11, and the inner hole of the main body 3 is provided with an annular stop 31. When the nozzle 1 is installed, one axial end face of the annular protrusion 11 is positioned and stopped by the annular stop 31. The head 2 and the main body 3 of the moving main contact are connected by a threaded structure, wherein the head 2 has a clamping part 21 for pressing the other axial end face of the annular protrusion 11. In this embodiment, the clamping part 21 extends into the inner hole of the main body 3, and an internal thread 33 is provided at the opening position of the inner hole of the main body 3. Figure 4 As shown), the clamping part 21 is provided with an external thread 211 ( Figure 3 As shown), the clamping part 21 is connected to the internal thread 33 of the inner hole of the main body part 3 through the external thread 211. This allows the head 2 to be installed on the main body part 3 while the clamping part 21 clamps the other side of the annular protrusion 11 in the axial direction. The clamping part 21 and the annular stop part 31 work together to clamp the annular protrusion 11 of the nozzle 1. By clamping the annular protrusion 11 at both ends in the axial direction, the nozzle 1 can be prevented from loosening, thereby ensuring the sealing of the contact part between the annular protrusion 11 and the annular stop part 31, and ensuring that the arc extinguishing effect of the nozzle 1 is not affected.

[0038] Furthermore, such as Figure 2 and Figure 3 As shown, the head 2 also includes a stop 22 connected to the clamping part 21. The stop 22 has a stop surface 221 that cooperates with the end face of the main body 3. The outer peripheral surface of the stop 22 is aligned with the outer peripheral surface of the main body 3, so that the moving main contact consists of only two parts, eliminating the arc-resistant ring in the prior art, reducing the number of parts, simplifying the structural design, reducing manufacturing costs, and facilitating assembly. In this embodiment, the head 2 directly serves as an ablation-resistant head, which is made of an ablation-resistant material, such as copper or copper-tungsten alloy. The main body 3 is made of aluminum, which ensures that the moving main contact has ablation-resistant properties while reducing the weight of the moving main contact. This allows the movable part assembly to maintain breaking stability while also having the advantage of lightweight design.

[0039] like Figure 2 and Figure 3 As shown, the side of the stop portion 22 facing away from the stop surface 221 is curved to prevent tip discharge. The clamping portion 21 has an L-shaped cross-section and includes a long section and a short section connected vertically. The long section has the aforementioned external thread 211, and the short section has an anti-rotation groove 212 for engaging with a screwing tool to prevent rotation. By setting the cross-sectional shape of the clamping portion 21 to L-shape, weight can be reduced on the one hand, and the machining and manufacturing of the head 2 can be facilitated on the other hand. In addition, by providing the anti-rotation groove 212 on the short section, the installation of the head 2 can be facilitated.

[0040] In this embodiment, the outer peripheral surface of the annular protrusion 11 and the inner wall surface of the main body 3 are in a smooth fit. A first elastic element 6 is provided between the annular protrusion 11 and the annular stop 31. The first elastic element 6 is specifically a sealing ring, which not only achieves a seal between the annular protrusion 11 and the annular stop 31, but also applies a reaction force to the annular protrusion 11 through elastic deformation, thereby applying a reaction force to the head 2 to achieve the purpose of preventing loosening and making the assembly of the nozzle 1 and the moving main contact more stable. In addition, as shown in the figure... Figure 4 As shown, a stop step 32 is provided at the end of the internal thread 33 in the inner hole of the main body 3, in conjunction with... Figure 2 As shown, the clamping part 21 simultaneously clamps the stop step 32 and the other side end face of the annular protrusion 11 in the axial direction, which facilitates the installation of the head 2.

[0041] like Figure 1 and Figure 2 As shown, a partition 34 for forming a thermal expansion chamber is provided inside the main body 3. The moving arc contact 4 is located inside the thermal expansion chamber and its end abuts against the partition 34. A screw 51 is provided at the end of the operating rod 5. The screw 51 passes through the partition 34 and is threadedly connected to the moving arc contact 4, thereby achieving a fixed connection between the moving arc contact 4, the operating rod 5, and the partition 34. Furthermore, a second elastic element 7 is provided between the moving arc contact 4 and the partition 34. The second elastic element 7 is specifically a spring. A mounting groove for installing the spring is provided on the end face of the partition 34 facing the moving arc contact 4. Using a spring as the second elastic element 7 can, on the one hand, apply a reaction force to the moving arc contact 4 through elastic deformation, and then apply a reaction force to the operating rod 5 to achieve the purpose of preventing loosening and making the assembly of the movable part more stable; on the other hand, the spring has good heat resistance and is not prone to high-temperature aging.

[0042] like Figure 2 As shown, a groove is provided on the side end face of the partition 34 facing away from the moving arc contact 4, and a boss 52 is provided on the outer periphery of the operating rod 5. The boss 52 is embedded in the groove and presses against the bottom wall of the groove, which facilitates the blocking of the operating rod 5, facilitates the installation of the operating rod 5, and does not occupy extra space in the main body 3.

[0043] In summary, the connections between the nozzle 1, head 2, and main body 3, and between the moving arc contact 4, operating rod 5, and partition 34 in this invention do not use screws. This not only reduces the volume and weight of the movable part assembly and the operational effort required for assembly during interruption, thus lowering the cost of the arc-extinguishing chamber, but also simplifies the assembly structure. The screwless structure saves assembly time and enhances practicality. Furthermore, this invention incorporates an anti-loosening structure, employing a first elastic element and a second elastic element to ensure more stable assembly of the movable part, making the arc-extinguishing chamber safer and more reliable during circuit breaker interruption.

[0044] In other embodiments of the assembly of the movable part of the arc-extinguishing chamber: the groove may not be provided on the side end face of the partition facing away from the moving arc contact, in which case the boss directly stops the end face of the partition; in other embodiments, the boss may not be provided on the operating rod, but the operating rod may be set as a stepped rod, with the front small diameter section being a screw and the rear large diameter section being a smooth rod, and a stepped surface is formed between the screw and the smooth rod, which is stopped by the step surface and the end face of the partition or by the bottom wall of the groove.

[0045] In other embodiments of the movable part assembly of the arc-extinguishing chamber: the second elastic element can also be a sealing ring, in which case it is necessary to replace the sealing ring after a period of time. Of course, in other embodiments, the second elastic element may not be provided.

[0046] In other embodiments of the movable part assembly of the arc-extinguishing chamber: the moving arc contact and the partition can also be connected by screws, and of course, the operating rod and the partition can also be connected by screws. Alternatively, in other embodiments, they can be fixed by welding.

[0047] In other embodiments of the assembly of the movable part of the arc-extinguishing chamber: the first elastic element can also be a spring. In this case, a sealing ring can be provided between the outer peripheral surface of the annular protrusion and the inner wall surface of the main body to ensure sealing. Of course, the sealing can also be achieved by the direct contact between the outer peripheral surface of the annular protrusion and the inner wall surface of the main body, as well as the direct contact between one side end face of the annular protrusion in the axial direction and the annular stop.

[0048] In other embodiments of the assembly of the movable part of the arc-extinguishing chamber, the first elastic element may not be provided.

[0049] In other embodiments of the assembly of the movable part of the arc-extinguishing chamber: the outer periphery of the annular protrusion and the inner wall of the main body can also be threaded together. On the basis of the threaded connection, the clamping part is used to press the other end face of the annular protrusion in the axial direction.

[0050] In other embodiments of the movable part assembly of the arc-extinguishing chamber: the cross-section of the clamping part can also be rectangular, in which case the anti-rotation groove is directly provided on the end face of the clamping part facing away from the annular protrusion. In other embodiments, the anti-rotation groove for engaging with the screwing tool to prevent rotation can also be provided on the stop part.

[0051] In other embodiments of the assembly of the movable part of the arc-extinguishing chamber: the head can also be an aluminum part. In this case, an arc-resistant ring can be set as in the prior art. The arc-resistant ring is made of copper or copper-tungsten alloy. In this case, the outer diameter of the stop part needs to be smaller than the outer diameter of the main body. After the head is threaded onto the main body, it is clamped together with the main body to clamp the arc-resistant ring.

[0052] In other embodiments of the assembly of the movable part of the arc-extinguishing chamber: the clamping part may not extend into the inner hole of the main body. The clamping part directly clamps the end face of the main body and also clamps the other end face of the annular protrusion along the axial direction. At this time, the head includes a sleeve part sleeved outside the main body. The sleeve part is provided with an internal thread, and the main body is provided with an external thread. The sleeve part is connected to the external thread on the main body through the internal thread.

[0053] In other embodiments of the assembly of the movable part of the arc-extinguishing chamber: the screw of the operating rod and the partition can also be threadedly connected, that is, both the partition and the moving arc contact are provided with threaded holes that cooperate with the screw of the operating rod.

[0054] The embodiment of the arc-extinguishing chamber in this invention is as follows: the arc-extinguishing chamber includes a shell and a movable part assembly disposed within the shell. The specific structure of the movable part assembly is the same as that of the movable part assembly of the arc-extinguishing chamber in the above embodiment, and will not be repeated here.

[0055] An embodiment of the circuit breaker of the present invention is as follows: the circuit breaker includes an arc-extinguishing chamber and an operating mechanism. The arc-extinguishing chamber includes a housing and a movable part assembly disposed within the housing. The specific structure of the movable part assembly is the same as that of the movable part assembly of the arc-extinguishing chamber in the above embodiment, and will not be repeated here.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A movable part assembly for an arc-extinguishing chamber, comprising a moving main contact and a nozzle, the moving main contact comprising a main body and a head connected by a threaded structure, an annular stop portion disposed in the inner hole of the main body, and the nozzle comprising an annular protrusion, one axial end face of the annular protrusion being used for positioning and stopping with the annular stop portion, characterized in that, The head has a clamping part for pressing the other end face of the annular protrusion axially. The clamping part is used to cooperate with the annular stop part to clamp the annular protrusion of the nozzle when the head and the main body are threadedly connected.

2. The movable part assembly of the arc-extinguishing chamber according to claim 1, characterized in that, The clamping part extends into the inner hole of the main body. The opening of the inner hole of the main body is provided with an internal thread, and the clamping part is provided with an external thread. The clamping part is connected to the inner hole of the main body through the external thread.

3. The movable part assembly of the arc-extinguishing chamber according to claim 2, characterized in that, The head is made of an ablation-resistant material. The head also includes a stop part that is connected to the clamping part and cooperates with the end face stop of the main body. The outer peripheral surface of the stop part is aligned with the outer peripheral surface of the main body.

4. The movable part assembly of the arc-extinguishing chamber according to claim 2 or 3, characterized in that, The clamping part has an L-shaped cross-section and includes a long section and a short section connected vertically. The long section is provided with the external thread, and the short section is provided with an anti-rotation groove for engaging with a turning tool to prevent rotation.

5. The movable part assembly of the arc-extinguishing chamber according to claim 2 or 3, characterized in that, The outer peripheral surface of the annular protrusion and the inner wall surface of the main body are in a smooth fit. A first elastic element is provided between the annular protrusion and the annular stop. A stop step is provided at the end of the internal thread in the inner hole of the main body. The pressing part simultaneously presses the stop step and the other side end face of the annular protrusion along the axial direction.

6. The movable part assembly of the arc-extinguishing chamber according to any one of claims 1 to 3, characterized in that, The movable part assembly of the arc-extinguishing chamber also includes a moving arc contact and an operating rod. A partition for forming a thermal expansion chamber is provided inside the main body. The moving arc contact is located inside the thermal expansion chamber and its end abuts against the partition. The end of the operating rod passes through the partition and is threadedly connected to the moving arc contact.

7. The movable part assembly of the arc-extinguishing chamber according to claim 6, characterized in that, A second elastic element is provided between the moving arc contact and the partition.

8. The movable part assembly of the arc-extinguishing chamber according to claim 6, characterized in that, A groove is provided on the side of the partition facing away from the moving arc contact, and a boss is provided on the outer periphery of the operating rod. The boss is embedded in the groove and presses against the bottom wall of the groove.

9. An arc-extinguishing chamber, comprising a shell and a movable part assembled within the shell, characterized in that, The movable part assembly is the movable part assembly of the arc-extinguishing chamber as described in any one of claims 1 to 8.

10. A circuit breaker, comprising an arc-extinguishing chamber and an operating mechanism, wherein the arc-extinguishing chamber comprises a housing and a movable part disposed within the housing, characterized in that, The movable part assembly is the movable part assembly of the arc-extinguishing chamber as described in any one of claims 1 to 8.

Images