An arc quenching system and circuit breaker

Abstract

The utility model relates to low -voltage switch technical field especially relates to an arc extinguishing system and circuit breaker. The arc extinguishing system includes static contact subassembly, moving contact subassembly, static arc -separating cover and dynamic arc -separating cover, wherein: static contact subassembly includes main static contact point and arc static contact point, moving contact subassembly includes main moving contact and arc moving contact, static arc -separating cover sets up on static contact subassembly and is covered at least part main static contact point place, dynamic arc -separating cover sets up on moving contact subassembly, and dynamic arc -separating cover includes the arc -separating protruding that sets up between main moving contact and arc moving contact to separate both. The arc extinguishing system utilizes dynamic arc -separating cover and greatly reduces the breakdown failure problem caused by arc moving, arc static contact point place arc and charged particle overflow, strengthens the insulation of static contact subassembly place simultaneously by using static arc -separating cover, carries out insulation protection through dynamic, static contact subassembly two places, avoids the breakdown failure problem, and improves the breaking performance and arc extinguishing capacity of arc extinguishing system.

Description

Technical Field

[0001] This utility model relates to the field of low-voltage switch technology, and in particular to an arc extinguishing system and a circuit breaker. Background Technology

[0002] The arc extinguishing system is one of the key structures of an electrical switch. Typically, an arc extinguishing system includes main contacts, stationary contacts, and an arc extinguishing chamber. When the main contacts and stationary contacts break, an electric arc is generated. The arc extinguishing grids installed in the arc extinguishing chamber are used to cut the generated electric arc in order to extinguish it.

[0003] During the disconnection process, conventional arc extinguishing systems emit arc particles randomly under high temperature and pressure. Although there are methods such as magnetic blowing and air blowing to introduce the arc into the arc extinguishing chamber, a large number of charged particles still accumulate between the moving and stationary contacts, which can easily cause arc breakdown. Moreover, under high voltage conditions, arc breakdown becomes even easier, exacerbating the failure phenomenon that the arc cannot be extinguished after disconnection. Utility Model Content

[0004] The first objective of this invention is to provide an arc-extinguishing system to solve the technical problem in the prior art where charged particles accumulating between moving and stationary contacts can easily cause arc breakdown.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An arc-extinguishing system includes a stationary contact assembly, a moving contact assembly, a stationary arc-blocking shield, and a moving arc-blocking shield, wherein:

[0007] The stationary contact assembly includes a main stationary contact and an arc stationary contact;

[0008] The moving contact assembly includes an active contact for contacting or separating from the main stationary contact and an arc moving contact for contacting or separating from the arc stationary contact.

[0009] The static arc shield is disposed on the static contact assembly and covers at least a portion of the surface where the main static contact is located;

[0010] The dynamic arc-isolating cover is disposed on the dynamic contact assembly, and the dynamic arc-isolating cover includes an arc-isolating protrusion disposed between the active contact and the arc-moving contact to separate the two.

[0011] Furthermore, the stationary contact assembly also includes a stationary conductive rod, and both the main stationary contact and the stationary arc-blocking cover are disposed on the stationary conductive rod.

[0012] Furthermore, the static arc shield covers one end of the static conductive rod where the main static contact is located, and the static arc shield is provided with a first clearance hole or a first clearance groove for the main static contact to pass through.

[0013] And / or, the stationary contact assembly further includes a stationary arc-leading plate disposed on the stationary conductive rod, the arc stationary contact being disposed on the stationary arc-leading plate, and the stationary arc-isolating cover further covering at least a portion of the stationary arc-leading plate;

[0014] And / or, the static arc shield is provided with a second clearance groove or a second clearance hole or clearance channel for the arc-blocking protrusion to pass through;

[0015] And / or, the static arc-isolating cover is provided with a core arc-isolating surface, which covers the surface of the main static contact on the static conductive rod above the surface of the main static contact and is lower than the side of the main static contact that contacts the active contact.

[0016] Furthermore, the moving contact assembly also includes a contact support, on which the active contact and the arcing contact are mounted side by side, and the moving arc shield is mounted on the contact support.

[0017] Furthermore, the dynamic arc-isolating cover and the contact support form an area for accommodating the active contact and the arcing contact;

[0018] And / or, the contact support is provided with a mounting slot, and the arc-blocking protrusion is inserted into the mounting slot;

[0019] And / or, the dynamic arc-isolating cover includes a U-shaped cover, the arc-isolating protrusion is connected between the U-shaped cover and the contact support, and divides the area formed by the U-shaped cover and the contact support into a first area and a second area, wherein the first area is used to accommodate the active contact, and the second area is used to accommodate the arc-moving contact;

[0020] And / or, the contact support is provided with a rib, which is disposed between the active contact and the arcing contact.

[0021] Furthermore, there are two arc-blocking protrusions, which are respectively disposed on both sides of the plane perpendicular to the arc-moving contact; the dynamic arc-blocking cover also includes a baffle connected between the two arc-blocking protrusions.

[0022] Furthermore, it also includes an arc-extinguishing chamber, which has an arc-extinguishing cavity. The main stationary contact and the active contact are both placed outside the arc-extinguishing cavity, while the arc stationary contact is placed inside the arc-extinguishing cavity. The end of the active contact used to contact the arc stationary contact is always placed inside the arc-extinguishing cavity during movement.

[0023] Furthermore, the arc-extinguishing chamber includes two spaced-apart gas-generating components and a grid assembly, which together form the arc-extinguishing cavity; wherein, the two gas-generating components respectively form the two side walls of the arc-extinguishing cavity and are located on opposite sides of the arcing contact.

[0024] Furthermore, the static arc-isolating shield extends from the static contact assembly toward the arc-extinguishing chamber and extends into the arc-extinguishing chamber;

[0025] And / or, the arc-extinguishing chamber is provided with a clearance arc surface on the side near the active contact, the center of the clearance arc surface is the rotation center of the stationary contact assembly, and the end of the active contact that contacts the main stationary contact is disposed opposite to the clearance arc surface.

[0026] Furthermore, the arc-blocking protrusion extends from the moving contact assembly toward the arc-extinguishing chamber;

[0027] One end of the arc-isolating protrusion near the arc-extinguishing chamber is placed inside the arc-extinguishing cavity and engages with the two side walls of the arc-extinguishing cavity, or the end of the arc-isolating protrusion near the arc-extinguishing chamber engages with the end face of the arc-extinguishing cavity.

[0028] Furthermore, a limiting groove is provided on the end face of the arc-extinguishing cavity, and the arc-blocking protrusion is inserted into the limiting groove.

[0029] The second objective of this invention is to provide a circuit breaker that includes the arc-extinguishing system described in any of the preceding claims.

[0030] The beneficial effects of this utility model are as follows:

[0031] This invention provides an arc-extinguishing system and a circuit breaker. The arc-extinguishing system includes a stationary contact assembly, a moving contact assembly, a stationary arc-isolation cover, and a moving arc-isolation cover. The stationary contact assembly includes a main stationary contact and an arc-stationary contact. The moving contact assembly includes an active contact for contacting or separating from the main stationary contact and an arc-moving contact for contacting or separating from the arc-stationary contact. The stationary arc-isolation cover is disposed on the stationary contact assembly and covers at least a portion of the surface where the main stationary contact is located. The moving arc-isolation cover is disposed on the moving contact assembly and includes an arc-isolation protrusion disposed between the active contact and the arc-moving contact to separate them. This arc-extinguishing system significantly reduces breakdown failure caused by arcing and charged particle leakage at the moving and stationary contacts by utilizing the moving arc-isolation cover. Simultaneously, the stationary arc-isolation cover strengthens the insulation at the stationary contact assembly. By providing insulation protection at both the moving and stationary contact assemblies, breakdown failure is avoided, thus improving the breaking performance and arc-extinguishing capability of the arc-extinguishing system. Attached Figure Description

[0032] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0033] Figure 1 This is a three-dimensional schematic diagram of the arc extinguishing system provided in Embodiment 1 of this utility model at one angle;

[0034] Figure 2 This is a cross-sectional schematic diagram of the arc extinguishing system provided in Embodiment 1 of this utility model;

[0035] Figure 3 This is an assembly diagram of the stationary contact assembly, the stationary arc-isolating cover, the moving contact assembly, and the moving contact cover provided in Embodiment 1 of this utility model;

[0036] Figure 4 A three-dimensional schematic diagram of the stationary contact assembly provided in Embodiment 1 of this utility model;

[0037] Figure 5 This is a three-dimensional schematic diagram of the static isolation arc cover provided in Embodiment 1 of this utility model at one angle;

[0038] Figure 6 This is a three-dimensional schematic diagram of the static isolation arc cover provided in Embodiment 1 of this utility model from another angle;

[0039] Figure 7 This is a three-dimensional schematic diagram of the moving contact assembly and the moving contact cover after being fastened together, according to Embodiment 1 of this utility model.

[0040] Figure 8 A three-dimensional schematic diagram of the moving contact assembly provided in Embodiment 1 of this utility model;

[0041] Figure 9 A three-dimensional schematic diagram of the moving contact cover provided in Embodiment 1 of this utility model;

[0042] Figure 10 A three-dimensional schematic diagram of the contact support member provided in Embodiment 1 of this utility model;

[0043] Figure 11 This is a three-dimensional schematic diagram of the arc extinguishing system provided in Embodiment 1 of this utility model from another angle;

[0044] Figure 12 A three-dimensional schematic diagram of the arc-extinguishing chamber provided in Embodiment 1 of this utility model;

[0045] Figure 13This is a three-dimensional schematic diagram of the static isolation arc cover provided in Embodiment 2 of this utility model at one angle;

[0046] Figure 14 This is a three-dimensional schematic diagram of the static isolation arc cover provided in Embodiment 2 of this utility model from another angle;

[0047] Figure 15 This is a cross-sectional view of the stationary contact assembly, moving contact assembly, stationary arc-blocking cover, and moving arc-blocking cover in their assembled state, as provided in Embodiment 2 of this utility model.

[0048] Figure 16 for Figure 15 Enlarged view of point A in the middle;

[0049] Figure 17 A three-dimensional schematic diagram of the static isolation arc cover provided in Embodiment 3 of this utility model;

[0050] Figure 18 This is a cross-sectional view of the stationary contact assembly, moving contact assembly, stationary arc-blocking cover, and moving arc-blocking cover in their assembled state, as provided in Embodiment 3 of this utility model.

[0051] Figure 19 for Figure 18 Enlarged view of point B in the middle.

[0052] icon:

[0053] 1-Static contact assembly; 11-Static conductive rod; 12-Main static contact; 13-Arc static contact; 14-Static arc-inducing plate; 141-Third clearance groove; 2-Moving contact assembly; 21-Contact support; 211-Mounting slot; 212-Rib; 213-Shaft limiting groove; 22-Active contact; 23-Arc moving contact; 24-Shaft; 3-Static arc-isolating cover; 31-First clearance hole; 32-Second clearance groove; 33-Core arc-isolating surface; 34-Second clearance hole; 35-Matching arc plate; 36-Clearing channel; 4-Moving arc-isolating cover; 41-Arch-isolating protrusion; 42-U-shaped cover; 43-Baffle; 5-Arc-extinguishing chamber; 51-Arc-extinguishing cavity; 52-Clearing arc surface. Detailed Implementation

[0054] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. It should be noted that in the description of this utility model, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. It should be noted that in the description of this utility model, the terms "connection" and "installation" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or a connection through an intermediate medium; it can be a mechanical connection or an electrical connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0055] Example 1

[0056] In conventional arc extinguishing systems, charged particles accumulating between the moving and stationary contacts during the breaking process can easily cause arc breakdown, leading to a failure where the arc cannot be extinguished after breaking.

[0057] Based on this, Embodiment 1 of this application provides an arc extinguishing system, referring to... Figures 1 to 3 The arc-extinguishing system includes a stationary contact assembly 1, a moving contact assembly 2, a stationary arc-isolating shield 3, and a moving arc-isolating shield 4. The stationary contact assembly 1 includes a main stationary contact 12 and an arc-stationary contact 13. The moving contact assembly 2 includes an active contact 22 for contacting or separating from the main stationary contact 12 and an arc-moving contact 23 for contacting or separating from the arc-stationary contact 13. The stationary arc-isolating shield 3 is disposed on the stationary contact assembly 1 and covers at least a portion of the surface where the main stationary contact 12 is located. The moving arc-isolating shield 4 is disposed on the moving contact assembly 2 and includes an arc-isolating protrusion 41 disposed between the active contact 22 and the arc-moving contact 23 to separate them. Specifically, the active contact 22 has an active contact for contacting or separating from the main stationary contact 12, and the arc-moving contact 23 has an arc-moving contact for contacting or separating from the arc-stationary contact 13. In most cases, the active and stationary contacts are silver alloy contacts, and the arc-moving and stationary contacts are silver-copper alloy contacts.

[0058] The arc extinguishing system provided in this application includes an arc-moving contact 23, whose main function is to withstand the electric arc generated during the opening and closing of the circuit breaker. The specific working principle of the arc-moving contact 23 is as follows: When the circuit breaker is opened, the moving contact assembly 2 moves relative to the stationary contact assembly 1. During the movement, the arc-moving contact 23 separates from the stationary contact assembly 1 after the active contact 22, causing an electric arc to be generated on the arc-moving contact 23, thereby achieving the purpose of protecting the active contact 22. When the circuit breaker is closed, the moving contact assembly 2 moves relative to the stationary contact assembly 1. During the movement, the arc-moving contact 23 contacts the stationary contact assembly 1 before the active contact 22, thereby preventing the generation of an electric arc on the main contact.

[0059] The arc-extinguishing system includes a static arc-isolating shield 3 and a dynamic arc-isolating shield 4 made of insulating material. After the circuit is broken, since the moving contact 23 separates from the static contact assembly 1 after the active contact 22, the arc and charged particles accumulate between the static contact 13 and the moving contact 23. Furthermore, since the active contact 22 and the moving contact 23 are separated by the arc-isolating protrusion 41, the arc-isolating protrusion 41 can block the arc and charged particles at the moving contact 23, preventing the arc and charged particles from exiting through the moving contact 23. The charge particles are transferred to the active contact 22. Although a large number of charged particles accumulate between the moving and stationary contacts, these particles are prevented from moving to the area between the active and stationary contacts by the arc-blocking protrusion 41, thus avoiding arcing caused by breakdown of the active and stationary contacts and improving breaking performance. Simultaneously, the static arc-blocking cover 3 covers at least part of the surface where the main stationary contact 12 is located, providing insulation protection for the end of the stationary contact assembly 1 closest to the moving contact assembly 2, further reducing arc breakdown caused by tip discharge. In summary, this arc-extinguishing system significantly reduces breakdown failure caused by arcing and overflow of charged particles at the moving and stationary contacts by utilizing the moving arc-blocking cover 4. At the same time, the static arc-blocking cover 3 strengthens the insulation at the stationary contact assembly 1. By providing insulation protection for both the moving and stationary contact assemblies, breakdown failure is avoided, improving the breaking performance and arc-extinguishing capability of the arc-extinguishing system.

[0060] Reference Figure 4 The stationary contact assembly 1 also includes a stationary conductive rod 11, on which the main stationary contact 12 and the stationary arc-isolating cover 3 are both mounted. The main stationary contact 12 is fixed to the stationary conductive rod 11 by riveting, welding, or embedding, while the stationary arc-isolating cover 3 is fixed to the stationary conductive rod 11 by snap-fitting or fastener connection. The stationary conductive rod 11 serves two purposes: firstly, to connect the main stationary contact 12 to an external circuit; and secondly, to support the main stationary contact 12 and the stationary arc-isolating cover 3. Furthermore, the stationary arc-isolating cover 3 can be fitted directly onto the stationary conductive rod 11 or there can be a certain gap between them, as long as it effectively prevents the stationary contact from failing due to breakdown.

[0061] Optionally, the static arc-blocking shield 3 can be installed on the static conductive rod 11 or on the circuit breaker housing. Preferably, the static arc-blocking shield 3 is installed on and adheres to the static conductive rod 11.

[0062] Reference Figure 4 and Figure 5 As an optional embodiment, based on the static contact assembly 1 including the static conductive rod 11:

[0063] The static arc shield 3 covers one end of the static conductive rod 11 where the main static contact 12 is located. The static arc shield 3 has a first clearance hole 31 or a first clearance groove for the main static contact 12 to pass through.

[0064] And / or, the stationary contact assembly 1 also includes a stationary arc-leading piece 14 disposed on the stationary conductive rod 11, an arc-stationary contact 13 disposed on the stationary arc-leading piece 14, and a stationary arc-blocking cover 3 further covering at least a portion of the stationary arc-leading piece 14.

[0065] And / or, the static arc shield 3 is provided with a second clearance hole or a second clearance groove 32 for the arc shield protrusion 41 to pass through;

[0066] And / or, the static arc-isolating cover 3 is provided with a core arc-isolating surface 33, which covers the surface of the main static contact 12 on the static conductive rod 11 and is lower than the side of the main static contact 12 that is in contact with the active contact 22.

[0067] In some embodiments, a main stationary contact 12 is provided on one end face of the stationary conductive rod 11, and the other end of the stationary conductive rod 11 is connected to an external circuit. A static arc-isolating cover 3 covers the end of the stationary conductive rod 11 where the main stationary contact 12 is provided. To prevent the main stationary contact 12 from being covered inside the static arc-isolating cover 3 and thus unable to contact the active contact 22, a first clearance hole 31 is provided on the static arc-isolating cover 3, through which the main stationary contact 12 passes; of course, the first clearance hole 31 can be replaced by a groove structure. The surface where the first clearance hole 31 is located on the static arc-isolating cover 3 (i.e., the core arc-isolating surface 33) should be lower than the surface of the main stationary contact 12 that contacts the active contact 22, so as not to obstruct the contact between the main stationary contact 12 and the active contact 22.

[0068] In some embodiments, the motion paths of the static arc-isolating shield 3 and the arc-isolating protrusion 41 are offset. In other embodiments, the static arc-isolating shield 3 is located on the motion path of the arc-isolating protrusion 41. For embodiments where the static arc-isolating shield 3 is located on the motion path of the arc-isolating protrusion 41, such as... Figure 5 As shown, in order to avoid the static arc shield 3 from obstructing the movement of the arc-blocking protrusion 41, a second clearance groove 32 is provided on the static arc shield 3 for the arc-blocking protrusion 41 to pass through; of course, the second clearance groove 32 can be replaced by a hole structure.

[0069] In some embodiments, continue to refer to Figure 4The stationary contact assembly 1 also includes a stationary arc-drawing plate 14 disposed on the stationary conductive rod 11. One end of the stationary arc-drawing plate 14 is connected to the end of the stationary conductive rod 11 where the main stationary contact 12 is disposed by fasteners, and the other end extends away from the main stationary contact 12. The arc stationary contact 13 is fixedly disposed on the stationary arc-drawing plate 14 by riveting, welding, embedding or other methods. At least a portion of the stationary arc-drawing plate 14 located between the main stationary contact 12 and the arc stationary contact 13 is covered by a stationary arc-isolating cover 3. The stationary arc-isolating cover 3 separates the stationary arc-drawing plate 14 from the moving contact assembly 2, which can prevent the electric arc and charged particles from being transferred to the main stationary contact 12 through the stationary arc-drawing plate 14, and prevent the stationary arc-drawing plate 14 from being corroded by the electric arc and charged particles generated when the current is interrupted, thereby improving the service life of the stationary arc-drawing plate 14.

[0070] Furthermore, the stationary arc-guiding plate 14 is generally located on the movement path of the arc-blocking protrusion 41. To prevent the stationary arc-guiding plate 14 from obstructing the movement of the arc-blocking protrusion 41, a third clearance groove 141 is provided on the stationary arc-guiding plate 14 for the arc-blocking protrusion 41 to pass through; of course, the third clearance groove can be replaced by a hole structure. In embodiments where part of the stationary arc-guiding plate 14 is covered by the stationary arc-blocking cover 3, the third clearance groove 141 overlaps with the second clearance groove 32.

[0071] In an embodiment where a stationary arc-drawing plate 14 and a core arc-blocking surface 33 are provided, the core arc-blocking surface 33 covers at least a portion of the stationary arc-drawing plate 14. In a specific embodiment, refer to... Figure 5 and Figure 6 The static arc-blocking cover 3 includes a horizontal cover plate and multiple vertical cover plates erected around the horizontal cover plate. The horizontal and vertical cover plates together form a protective area. The end of the static conductive rod 11 with the main static contact 12 and the end of the static arc-inducing plate 14 near the main static contact 12 are both covered within this protective area. The horizontal cover plate has a first clearance hole 31 and a second clearance groove 32. The main static contact 12 passes through the first clearance hole 31 to contact or separate from the active contact 22. The arc-blocking protrusion 41 moves through the second clearance groove 32 during the opening and closing of the circuit breaker.

[0072] Reference Figure 7 and Figure 8 The moving contact assembly 2 also includes a contact support 21, on which the active contact 22 and the arcing contact 23 are mounted side by side, and the moving arc-isolating cover 4 is mounted. The number of active contacts 22 and arcing contacts 23 can be one, two, or more; generally, the number of active contacts 22 is greater than the number of arcing contacts 23, and the multiple active contacts 22 are divided into two groups and respectively disposed on both sides of the plane perpendicular to the movement trajectory of the arcing contact 23. The moving arc-isolating cover 4 is fixed to the contact support 21 by snap-fitting, fastener connection, or other means; during the movement of the contact support 21, the moving arc-isolating cover 4 moves synchronously with the contact support 21.

[0073] In an embodiment where active contacts 22 are provided on both sides of the arcing contact 23, there are also two arc-blocking protrusions 41. One, two or more arcing contacts 23 are provided between the two arc-blocking protrusions 41, and several active contacts 22 are provided on the side of each arc-blocking protrusion 41 away from the arcing contact 23.

[0074] Based on the moving contact assembly 2 including the contact support 21, as an optional embodiment:

[0075] The dynamic arc-isolating cover 4 and the contact support 21 together form an area for accommodating the active contact 22 and the arcing contact 23;

[0076] And / or, the contact support 21 is provided with a mounting slot 211, and the arc-blocking protrusion 41 is inserted into the mounting slot 211;

[0077] And / or, the dynamic arc-isolating cover 4 includes a U-shaped cover 42, an arc-isolating protrusion 41 connected between the U-shaped cover 42 and the contact support 21, and divides the area enclosed by the U-shaped cover 42 and the contact support 21 into a first area and a second area, wherein the first area is used to accommodate the active contact 22 and the second area is used to accommodate the arc-moving contact 23.

[0078] And / or, a stiffener 212 is provided on the contact support 21, and the stiffener 212 is disposed between the active contact 22 and the arcing contact 23.

[0079] Reference Figure 9 and Figure 10 In some embodiments, the dynamic arc-isolating cover 4 includes a U-shaped cover 42, and the contact support 21 is also generally U-shaped. The open ends of the U-shaped cover 42 and the contact support 21 are opposite to each other and are fastened together. The active contact 22 and the arcing contact 23 are located between the dynamic arc-isolating cover 4 and the contact support 21. One end of the arc-isolating protrusion 41 is fixed to the inner end face of the closed end of the U-shaped cover 42, and the other end of the arc-isolating protrusion 41 contacts the inner end face of the closed end of the contact support 21, thereby dividing the area enclosed by the U-shaped cover 42 and the contact support 21 into a first area and a second area. The first area is used to accommodate the active contact 22, and the second area is used to accommodate the arcing contact 23. The active contact 22 and the arcing contact 23 are separated by the arc-isolating protrusion 41. Furthermore, in order to improve the connection stability of the contact position between the arc-blocking protrusion 41 and the contact support 21, a mounting slot 211 is provided on the inner end face of the closed end of the contact support 21, and the arc-blocking protrusion 41 is inserted into the mounting slot 211.

[0080] Optionally, the dynamic arc isolation cover 4 and the contact support 21 are fixed by one or more methods such as shaft hole connection, snap-fit, and fastener (e.g., screws, pins, etc.). In addition, the dynamic arc isolation cover 4 can be manufactured as a whole using a one-piece molding process, or the various parts that make up the dynamic arc isolation cover 4 can be spliced ​​into a whole by snap-fit, fastener connection, etc.

[0081] In some embodiments, continue to refer to Figure 10 The contact support 21 is provided with a stiffener 212, which is positioned between the active contact 22 and the arcing contact 23. The stiffener 212 positions the active contact 22 and the arcing contact 23, preventing axial movement of the moving contacts relative to the contact support 21 during rotation and improving the positioning accuracy of each moving contact. In embodiments where active contacts 22 are provided on both sides of the arcing contact 23, there are also two stiffeners 212, with one, two, or more arcing contacts 23 positioned between the two stiffeners 212; several active contacts 22 are provided on the side of each stiffener 212 away from the arcing contact 23.

[0082] Furthermore, the moving contact assembly 2 also includes a rotating shaft 24 disposed on the contact support 21, with the active contact 22 and the arcing contact 23 mounted side by side on the rotating shaft 24; a rotating shaft limiting groove 213 is provided on the stiffener 212, and part of the rotating shaft 24 is embedded in the rotating shaft limiting groove 213. The rotating shaft limiting groove 213 can limit the position of the rotating shaft 24 relative to the contact support 21, and can also support the body of the rotating shaft 24.

[0083] Reference Figure 11 and Figure 12 The arc-extinguishing system further includes an arc-extinguishing chamber 5, which has an arc-extinguishing cavity 51. The main stationary contact 12 and the active contact 22 are both located outside the arc-extinguishing cavity 51, while the arc stationary contact 13 is located inside the arc-extinguishing cavity 51. The end of the arc-moving contact 23 that contacts the arc stationary contact 13 is always located inside the arc-extinguishing cavity 51 during movement. Specifically, the arc-extinguishing chamber 5 includes two spaced-apart gas-generating elements and a grid plate assembly. At least some of the grid plates in the grid plate assembly form a U-shaped structure consisting of the grid plate belly and two grid plate legs. The two grid plate legs are respectively inserted into the two gas-generating elements. In this way, the two gas-generating elements and the grid plate assembly surround and form the arc-extinguishing cavity 51. The side of the arc-extinguishing cavity 51 away from the grid plate assembly forms an opening facing the moving contact assembly 2. The two gas-generating components form the two side walls of the arc-extinguishing cavity 51, respectively, and are located on opposite sides of the arc-moving contact 23. The end face of the arc-extinguishing cavity 51 is the side opposite to the active contact 22, that is, the side of the arc-extinguishing cavity 51 facing the opening of the moving contact assembly 2. Since the active and stationary contacts are located outside the arc-extinguishing cavity 51, while the arc-moving and stationary contacts are located inside the arc-extinguishing cavity 51, the arc generated when the circuit breaker is tripped is generated inside the arc-extinguishing cavity 51.

[0084] As an optional embodiment, the arc-blocking protrusion 41 extends from the moving contact assembly 2 toward the arc-extinguishing chamber 5; one end of the arc-blocking protrusion 41 near the arc-extinguishing chamber 5 is placed inside the arc-extinguishing cavity 51 and cooperates with the two side walls of the arc-extinguishing cavity 51, or, one end of the arc-blocking protrusion 41 near the arc-extinguishing chamber 5 cooperates with the end face of the arc-extinguishing cavity 51 (i.e., the face of the arc-extinguishing cavity 51 facing the opening of the moving contact assembly 2).

[0085] In some embodiments, refer to Figure 11 The arc-blocking protrusion 41 extends from the moving contact assembly 2 toward the opening of the arc-extinguishing cavity 51 and inserts into the arc-extinguishing cavity 51. The end of the arc-blocking protrusion 41 near the arc-extinguishing chamber 5 is always placed inside the arc-extinguishing cavity 51 during the movement. The two arc-blocking protrusions 41 are in contact with each other or have a certain gap with the two side walls of the arc-extinguishing cavity 51, so that the arc-blocking protrusion 41 and the opposite side walls of the arc-moving contact 23 together form a defense line that separates the moving contact 23 and the active contact 22, further avoiding the problem of electric arc and charged particles overflowing from the arc-extinguishing cavity 51.

[0086] In other embodiments, limiting grooves are provided on the two end faces of the arc-extinguishing cavity 51 (specifically, the gas-generating component) on the open side (i.e., the two end faces opposite to the active contact 22). The distance between the two arc-blocking protrusions 41 is greater than the distance between the two opposing inner wall surfaces of the arc-moving contact 23 on both sides of the arc-extinguishing cavity 51. Simultaneously, the two arc-blocking protrusions 41 correspond one-to-one with the limiting grooves on the two end faces of the arc-extinguishing cavity 51. The arc-blocking protrusions 41 extend from the moving contact assembly 2 towards the arc-extinguishing chamber 5 and insert into the limiting grooves, achieving a plug-in fit between the arc-blocking protrusions 41 and the end faces of the arc-extinguishing cavity 51. In this embodiment, the arc-blocking protrusions 41 and the end faces of the arc-extinguishing cavity 51 together form a protective line separating the arc-moving contact 23 and the active contact 22. Alternatively, the end face may not have a limiting groove. The arc-blocking protrusion 41 extends from the moving contact assembly 2 to the arc-extinguishing chamber 51 to the end face, which can also form a protective line separating the arc-moving contact 23 and the active contact 22. Setting a limiting groove can prevent charged particles from overflowing from the junction of the arc-extinguishing chamber 5 and the arc-blocking protrusion 41, resulting in a better arc-blocking effect.

[0087] Based on the above structure, to avoid contact friction between the arc-isolating protrusion 41 and the arc-extinguishing chamber 5, which would affect the movement of the moving contact assembly 2, the vertical distance between the sidewall or end face or limiting groove of the arc-isolating protrusion 41 and the arc-extinguishing chamber 51 should be in the range of 0.5mm to 2mm. This structure creates a slit between the arc-isolating protrusion 41 and the sidewall or end face or limiting groove of the arc-extinguishing chamber 51. This prevents friction between the arc-isolating protrusion 41 and the sidewall or end face or limiting groove of the arc-extinguishing chamber 51 from affecting the movement of the moving contact assembly 2, and also makes it difficult for the electric arc and charged particles inside the arc-extinguishing chamber 51 to escape from this slit.

[0088] In some embodiments, a clearance arc surface 52 is provided on the side of the arc-extinguishing chamber 5 near the active contact 22. The center of the clearance arc surface 52 is the rotation center of the stationary contact assembly 1, and one end of the active contact 22 that contacts the main stationary contact 12 is positioned opposite to the clearance arc surface 52. By providing the clearance arc surface 52, the size of the gap between the active contact 22 and the arc-extinguishing chamber 5 can be kept constant during movement. The clearance arc surface 52 is also the end face described above; when a limiting groove is provided on the end face, the bottom surface of the limiting groove is also an arc surface with the rotation center of the stationary contact assembly 1 as its center. When the arc-blocking protrusion 41 and the end face or limiting groove of the arc-extinguishing cavity 51 are engaged, the arc surface can keep the size of the gap between the arc-blocking protrusion 41 and the end face or limiting groove of the arc-extinguishing cavity 51 constant, making it difficult for the electric arc and charged particles in the arc-extinguishing cavity 51 to overflow from the gap.

[0089] In some embodiments, continue to refer to Figure 2 The static arc-inducing plate 14 extends away from the static conductive rod 11 towards the arc-extinguishing chamber 5 and protrudes into the arc-extinguishing chamber 5. The static arc-inducing plate 14 and the arc-extinguishing chamber 5 are in... Figure 2 The projections in the height direction of the middle part at least partially overlap. The static arc-initiating plate 14 and the arc-extinguishing chamber 5 are in... Figure 2 The projected portions in the height direction coincide, and the stationary arc-inducing plate 14 provides support for the stationary arc contact 13 placed inside the arc-extinguishing chamber 51, while guiding the arc at the stationary contact assembly 1 into the arc-extinguishing chamber 51. Furthermore, the stationary arc-isolating shield 3 extends from the stationary conductive rod 11 towards and into the arc-extinguishing chamber 5, and the stationary arc-isolating shield 3 and the arc-extinguishing chamber 5 are in... Figure 2 The projection portions in the height direction overlap; the static arc shield 3 simultaneously covers the side of the static conductive rod 11 and the static arc-leading plate 14 near the moving contact assembly 2, providing insulation protection for the static conductive rod 11 and the static arc-leading plate 14.

[0090] Based on the above structure, with the arc stationary contact 13 as the dividing point, the side of the stationary arc-drawing plate 14 closest to the main stationary contact 12 is covered by the stationary arc-isolating cover 3, while the side of the stationary arc-drawing plate 14 furthest from the main stationary contact 12 is located inside the arc-extinguishing chamber 5.

[0091] In some embodiments, continue to refer to Figure 9 There are two arc-blocking protrusions 41, which are respectively located on both sides of the arc-moving contact 23 perpendicular to its movement trajectory; the moving arc-blocking cover 4 also includes a baffle 43 connected between the two arc-blocking protrusions 41. Figure 2 , Figure 2The state shown is that the moving and stationary contact assemblies are separated but not completely separated. In this state, the baffle 43 extends from the arcing contact 23 to the stationary arc-isolating cover 3. One end of the baffle 43 abuts against the arcing contact 23, and the other end extends through the stationary arc-isolating cover 3 (i.e., below the stationary arc-isolating cover 3). At the same time, along the direction of the movement trajectory of the arcing contact (shown by the dotted line in the figure), one end of the arc-isolating protrusion 41 extends through the active contact 22 and the arcing contact 23 (i.e., above the active contact 22 and the arcing contact 23), and the other end extends through the main stationary contact 12 and the arc-stationary contact 13 (i.e., below the main stationary contact 12 and the arc-stationary contact 13). Since the arc is extinguished before the moving and stationary contact assemblies are fully separated, when the moving and stationary contact assemblies are fully separated, one end of the arc-blocking protrusion 41 passes through the active contact 22 and the arc-moving contact 23, while the other end can be above or below the main stationary contact 12 and the arc-stationary contact 13.

[0092] During the closing process, the contact support 21 drives the main and arcing contacts to rotate counterclockwise. Before the moving and stationary contact assemblies make contact, one end of the baffle 43 abuts against the arcing contact 23. When the arcing contact 23 just makes contact with the arcing stationary contact 13, the active contact 22 has not yet made contact with the main stationary contact 12. The contact support 21 continues to rotate counterclockwise until the active contact 22 makes contact with the main stationary contact 12, thus completing the closing action. Since the moving arc isolation cover 4 is fixed on the contact support 21 and moves with the contact support 21, there is a gap between one end of the baffle 43 and the arcing contact 23 in the closed state.

[0093] The baffle 43 serves several functions: First, it connects between the two arc-blocking protrusions 41, strengthening their structural integrity and preventing them from vibrating under the air pressure generated during circuit breaking. Second, it blocks the electric arc and charged particles generated during circuit breaking, preventing them from impacting the moving contact assembly 2 or entering the circuit breaker. Thirdly, the baffle 43 acts as an opening and closing door for the arc-extinguishing cavity 51. Specifically, when the circuit breaker closes, the baffle 43 moves to open the opening of the arc-extinguishing cavity 51, allowing air to circulate inside and outside the arc-extinguishing cavity 51; when the circuit breaker opens, the baffle 43 moves to close the opening of the arc-extinguishing cavity 51, creating a relatively enclosed space inside the arc-extinguishing cavity 51. This ensures that the arc and charged particles can only be discharged from the side of the arc-extinguishing cavity 51 furthest from the moving contact assembly 2 (i.e., the side of the grid assembly), preventing the arc and charged particles from overflowing to the active and stationary contacts and causing arc breakdown. Fourthly, the baffle 43 separates the arc-extinguishing cavity 51 from the belly of the arc-moving contact 23, preventing the arc and charged particles from eroding the belly of the arc-moving contact 23 and extending the service life of the arc-moving contact 23.

[0094] In summary, the arc extinguishing system provided in this application, after the moving and stationary contact assemblies are separated, forms a barrier between the moving and stationary contacts and the moving and stationary contacts by the arc-extinguishing cavity 51, with the arc-blocking protrusion 41 of the moving arc-blocking cover 4 and the side wall of the arc-extinguishing cavity 51 working together. Meanwhile, the baffle 43 of the moving arc-blocking cover 4 blocks the opening of the arc-extinguishing cavity 51, creating a relatively enclosed space inside the arc-extinguishing cavity 51. This effectively prevents most of the arc from overflowing outward from the opening of the arc-extinguishing cavity 51. At the same time, the small amount of overflowing arc is also difficult to contact the stationary contact assembly 1 under the protection of the stationary arc-blocking cover 3, thereby significantly reducing the breakdown failure problem caused by arc overflow and improving the arc extinguishing capability of the system.

[0095] Example 2

[0096] Embodiment 2 of this application provides an arc-extinguishing system, which differs from Embodiment 1 in that the structure of the static arc-isolating shield 3 is different. (Refer to...) Figures 13 to 16 In this embodiment, the side of the baffle 43 closest to the arc-extinguishing chamber 5 is the arc-blocking surface. The static arc-blocking cover 3 also includes a mating arc plate 35 disposed opposite to the arc-blocking surface. Both the arc-blocking surface and the mating arc plate 35 have their arc centers centered on the rotation center of the static contact assembly 1. Specifically, refer to... Figure 16 The static arc-isolating cover 3 has a second clearance hole 34 for the arc-isolating protrusion 41 to pass through. One end of the mating arc plate 35 is connected to one side wall of the second clearance hole 34, and the other end of the mating arc plate 35 extends in an arc shape away from the core arc-isolating surface 33 and passes through the third clearance groove 141 on the static arc-inducing plate 14. The mating arc plate 35 is located on the side of the horizontal cover away from the core arc-isolating surface 33, which prevents the mating arc plate 35 from obstructing the contact between the arc-moving contact 23 and the arc-stationary contact 13. A narrow gap is formed between the baffle 43 and the mating arc plate 35, making it difficult for the electric arc and charged particles in the arc-extinguishing cavity 51 to escape from the narrow gap. In order to avoid friction between the mating arc plate 35 and the baffle 43 affecting the movement of the baffle 43, the vertical distance between the mating arc plate 35 and the baffle 43 is between 0.5 mm and 2 mm.

[0097] In this embodiment, the sealing of the junction between the static arc shield 3 and the dynamic arc shield 4 is improved by using the arc plate 35, making it difficult for the electric arc and charged particles in the arc extinguishing cavity 51 to overflow from the junction between the static arc shield 3 and the dynamic arc shield 4.

[0098] Example 3

[0099] Embodiment 3 of this application provides an arc-extinguishing system, which differs from Embodiments 1 and 2 in that the structure of the static arc-isolating shield 3 is different. (Refer to...) Figures 17 to 19In this embodiment, the static arc-isolating cover 3 is provided with a clearance channel 36 for the arc-isolating protrusion 41 to pass through. The opposing surfaces of the clearance channel 36 and the baffle 43 are both arc surfaces with the rotation center of the static contact assembly 1 as the arc center. Specifically, a housing is provided on the side of the horizontal cover plate away from the core arc-isolating surface 33. The end of the housing near the horizontal cover plate is open to allow the arc-isolating protrusion 41 and the baffle 43 to be inserted. The end of the housing away from the horizontal cover plate may be open or closed, and the clearance channel 36 is formed inside the housing. In this embodiment, the clearance channel 36 further enhances the sealing performance at the junction of the static arc-isolating cover 3 and the dynamic arc-isolating cover 4.

[0100] In an embodiment where the end of the housing furthest from the horizontal cover is not open, one end of the clearance channel 36 is open and the other end is closed, and the arc-blocking protrusion 41 and the baffle 43 are inserted into the clearance channel 36 through the open end of the clearance channel 36. With this structure, the electric arc and charged particles generated when the circuit breaker is tripped have almost no chance of contacting the stationary conductive rod 11 and the portion of the stationary arc-inducing plate 14 located between the main and arc stationary contacts.

[0101] Example 4

[0102] Embodiment 4 of this application provides a circuit breaker with the arc-extinguishing system of any of the above embodiments. The number of arc-extinguishing systems in the circuit breaker can be reasonably set according to product specifications and actual usage requirements; exemplarily, the circuit breaker includes three parallel arc-extinguishing systems, forming a three-pole circuit in the phase containing the three arc-extinguishing systems. This circuit breaker at least has the beneficial effects of the above embodiments, which will not be elaborated further here.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. An arc extinguishing system, characterized in that, It includes a stationary contact assembly (1), a moving contact assembly (2), a stationary arc-blocking shield (3), and a moving arc-blocking shield (4), wherein: The stationary contact assembly (1) includes a main stationary contact (12) and an arc stationary contact (13); The moving contact assembly (2) includes an active contact (22) for contacting or separating from the main stationary contact (12) and an arc moving contact (23) for contacting or separating from the arc stationary contact (13); The static arc shield (3) is disposed on the static contact assembly (1) and covers at least part of the surface where the main static contact (12) is located; The dynamic arc-blocking cover (4) is disposed on the dynamic contact assembly (2), and the dynamic arc-blocking cover (4) includes an arc-blocking protrusion (41) disposed between the active contact (22) and the arc-moving contact (23) to separate the two.

2. The arc-extinguishing system according to claim 1, characterized in that, The stationary contact assembly (1) also includes a stationary conductive rod (11), and the main stationary contact (12) and the stationary arc shield (3) are both disposed on the stationary conductive rod (11).

3. The arc-extinguishing system according to claim 2, characterized in that, The static arc shield (3) covers one end of the static conductive rod (11) where the main static contact (12) is located. The static arc shield (3) has a first clearance hole (31) or a first clearance groove for the main static contact (12) to pass through. And / or, the stationary contact assembly (1) further includes a stationary arc-leading piece (14) disposed on the stationary conductive rod (11), the arc stationary contact (13) is disposed on the stationary arc-leading piece (14), and the stationary arc-blocking cover (3) also covers at least a portion of the stationary arc-leading piece (14). And / or, the static arc shield (3) is provided with a second clearance groove (32) or a second clearance hole (34) or clearance channel (36) for the arc-blocking protrusion (41) to pass through; And / or, the static arc shield (3) is provided with a core arc shielding surface (33), which covers the surface of the main static contact (12) on the static conductive rod (11) above it and is lower than the side of the main static contact (12) that contacts the active contact (22).

4. The arc-extinguishing system according to claim 1, characterized in that, The moving contact assembly (2) further includes a contact support (21), the active contact (22) and the arcing contact (23) are mounted side by side on the contact support (21), and the moving arc shield (4) is mounted on the contact support (21).

5. The arc-extinguishing system according to claim 4, characterized in that, The dynamic arc shield (4) and the contact support (21) together form an area for accommodating the active contact (22) and the arcing contact (23); And / or, the contact support (21) is provided with a mounting slot (211), and the arc-blocking protrusion (41) is inserted into the mounting slot (211); And / or, the dynamic arc-blocking cover (4) includes a U-shaped cover (42), the arc-blocking protrusion (41) is connected between the U-shaped cover (42) and the contact support (21), and divides the area formed by the U-shaped cover (42) and the contact support (21) into a first area and a second area, wherein the first area is used to accommodate the active contact (22), and the second area is used to accommodate the arc-moving contact (23); And / or, a stiffener (212) is provided on the contact support (21), the stiffener (212) being disposed between the active contact (22) and the arcing contact (23).

6. The arc-extinguishing system according to claim 1, characterized in that, There are two arc-blocking protrusions (41), which are respectively disposed on both sides of the arc-moving contact (23) perpendicular to the plane where its movement trajectory is located; the moving arc-blocking cover (4) also includes a baffle (43) connected between the two arc-blocking protrusions (41).

7. The arc-extinguishing system according to claim 1, characterized in that, It also includes an arc-extinguishing chamber (5), which has an arc-extinguishing cavity (51). The main stationary contact (12) and the active contact (22) are both located outside the arc-extinguishing cavity (51), and the arc stationary contact (13) is located inside the arc-extinguishing cavity (51). The end of the arc-moving contact (23) used to contact the arc stationary contact (13) is always located inside the arc-extinguishing cavity (51) during the movement.

8. The arc-extinguishing system according to claim 7, characterized in that, The arc-extinguishing chamber (5) includes two spaced-apart gas generating elements and grid plate groups, which together form the arc-extinguishing cavity (51); wherein, the two gas generating elements respectively form the two side walls of the arc-extinguishing cavity (51) and are located on opposite sides of the arc-moving contact (23).

9. The arc-extinguishing system according to claim 7, characterized in that, The static arc shield (3) extends from the static contact assembly (1) toward the arc-extinguishing chamber (5) and extends toward the arc-extinguishing chamber (5); And / or, the arc-extinguishing chamber (5) is provided with a clearance arc surface (52) on the side near the active contact (22), the center of the clearance arc surface (52) is the rotation center of the stationary contact assembly (1), and the end of the active contact (22) that contacts the main stationary contact (12) is disposed opposite to the clearance arc surface (52).

10. The arc-extinguishing system according to claim 7, characterized in that, The arc-blocking protrusion (41) extends from the moving contact assembly (2) toward the arc-extinguishing chamber (5); One end of the arc-blocking protrusion (41) near the arc-extinguishing chamber (5) is placed inside the arc-extinguishing cavity (51) and cooperates with the two side walls of the arc-extinguishing cavity (51), or the end of the arc-blocking protrusion (41) near the arc-extinguishing chamber (5) cooperates with the end face of the arc-extinguishing cavity (51).

11. The arc-extinguishing system according to claim 10, characterized in that, The end face of the arc extinguishing cavity (51) is provided with a limiting groove, and the arc blocking protrusion (41) is inserted into the limiting groove.

12. A circuit breaker, characterized in that, Including the arc extinguishing system as described in any one of claims 1 to 11.

Images