Arc extinguishing system and circuit breaker

Abstract

The utility model relates to the technical field of low-voltage electric appliances, in particular to an arc extinguishing system and a circuit breaker. The arc extinguishing system is used in cooperation with a contact system of the circuit breaker and comprises an arc extinguishing chamber and an arc isolating cover, the arc isolating cover is arranged between the arc extinguishing chamber and a rotating shaft, and the arc extinguishing chamber and the arc isolating cover define an arc isolating area; the movable end of the arc contact moves in the arc isolating area, and the movable end of the main contact moves outside the arc isolating area; one side, close to the rotating shaft, of the arc isolation cover is provided with a blocking structure used for preventing charged particles from overflowing towards the outside of the arc isolation area. As the movable end of the arc contact moves in the arc isolating area, the charged particles are isolated in the arc isolating area, and the charged particles are prevented from overflowing to the main contact; the plugging structure can plug the gap between the arc isolation cover and the rotating shaft, and prevents high-temperature charged particles returning towards the rotating shaft in the arc isolation area from overflowing from the gap between the arc isolation cover and the rotating shaft, thereby improving the breaking performance and safety performance of the arc extinguishing system.

Description

Technical Field

[0001] The utility model relates to the technical field of low-voltage electrical appliances, in particular to an arc extinguishing system and a circuit breaker. Background Art

[0002] The arc extinguishing system is one of the key structures of an electrical switch. Usually, the arc extinguishing system includes the main contact, the static contact and the arc extinguishing chamber. When the main contact and the static contact are disconnected, an arc will be generated. The arc extinguishing grid installed in the arc extinguishing chamber needs to be used to cut the generated arc to extinguish the arc. When the moving and static contacts of existing products are separated, the arc will generate high temperature, causing the internal gas to carry some charged particles and scatter in the arc extinguishing chamber, and even transfer to the main contact, which may cause the main contact to be broken down in severe cases.

[0003] In order to solve this problem, some products will add arc-isolating plates between the arc contact and the main contact to prevent the charged particles from transferring to the main contact. However, the existence of the arc-isolating plates prevents the gas from escaping to both sides of the arc contact, resulting in a higher gas pressure in the area between the arc-extinguishing chamber and the arc-isolating plates. The gas carrying high-temperature charged particles will retreat toward the contact system. When the concentration of high-temperature charged particles reaches a certain level, the charged particles will overflow from the gap between the arc-isolating plates and the rotating shaft, causing breakdown between the moving and static contacts, which is often called the back breakdown phenomenon, resulting in breaking failure. Utility Model Content

[0004] The first object of the utility model is to provide an arc extinguishing system to solve the technical problem in the prior art that charged particles are easily scattered onto the main contacts, resulting in current breaking failure.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] An arc extinguishing system is used in conjunction with a contact system of a circuit breaker, wherein the contact system comprises a stationary contact, a main contact, an arc contact and a rotating shaft, wherein the fixed end of the main contact and the fixed end of the arc contact are both connected to the rotating shaft, and the movable end of the main contact and the movable end of the arc contact are both capable of contacting or separating from the stationary contact; the arc extinguishing system comprises an arc extinguishing chamber and an arc shield, wherein:

[0007] The arc isolation cover is arranged between the arc extinguishing chamber and the rotating shaft, and the arc extinguishing chamber and the arc isolation cover are arranged to form an arc isolation area; the movable end of the arc contact moves within the arc isolation area, and the movable end of the main contact moves outside the arc isolation area; a blocking structure for blocking charged particles from escaping to the outside of the arc isolation area is arranged on the side of the arc isolation cover close to the rotating shaft.

[0008] Furthermore, the sealing structure includes a sealing plate with an arc-shaped structure, and a first opening is formed on the sealing plate for the arc contact to pass through; an arc-shaped surface is provided at one end of the rotating shaft close to the arc isolation cover, and a gap between the sealing plate and the arc-shaped surface is greater than or equal to 0 mm and less than or equal to 0.5 mm.

[0009] Furthermore, the blocking structure includes a first sealing strip, and the rotating shaft is provided with a first sealing groove for plugging and matching with the first sealing strip;

[0010] Alternatively, the sealing structure includes a second sealing groove, and the rotating shaft is provided with a second sealing strip for plugging and matching with the second sealing groove.

[0011] Furthermore, the rotating shaft comprises a shell and an arc-isolating cover plate, wherein the arc-isolating cover plate covers an opening of the shell near one end of the arc-isolating cover;

[0012] The fixed end of the main contact and the fixed end of the arc contact are both installed in the housing, and the arc isolation cover plate is provided with a second opening for the main contact and the arc contact to pass through.

[0013] Furthermore, the arc isolation cover comprises two arc isolation side plates which are arranged at intervals, and each of the arc isolation side plates extends from the arc extinguishing chamber to the rotating shaft; and the arc contact is arranged between the two arc isolation side plates.

[0014] Furthermore, one side of the two arc-isolating side plates close to the rotating shaft is connected to the blocking plate;

[0015] And / or, an arc isolation bottom plate is connected between the bottoms of the two arc isolation side plates.

[0016] Furthermore, the arc shield is fixed on the arc extinguishing chamber or on a product housing of the circuit breaker.

[0017] Furthermore, a pressure relief plate is provided on one side of the arc shield close to the arc extinguishing chamber, and a third opening for the arc contact to pass through is provided on the pressure relief plate;

[0018] The pressure relief plate and the arc extinguishing chamber are spaced apart, and a pressure relief area is formed between the two; the pressure relief area is connected to the arc extinguishing area;

[0019] The product housing of the circuit breaker is provided with an installation cavity, and the arc extinguishing system and the contact system are both arranged in the installation cavity; the opposite sides of the pressure relief plate are respectively abutted against the two inner side walls of the installation cavity;

[0020] There is a gap between the arc extinguishing chamber and the inner side wall of the installation cavity, and the gap between the two forms an external leakage channel, and two ends of the external leakage channel are respectively connected to the pressure relief area and the outside of the product shell.

[0021] Furthermore, each of the arc-isolating side plates is provided with a plurality of arc-shaped grooves on a side away from the arc-isolating area, and a plurality of limiting protrusions are provided on the main contacts close to the arc-isolating side plates. The plurality of arc-shaped grooves and the plurality of limiting protrusions are provided in a one-to-one correspondence, and the limiting protrusions are slidably provided in the corresponding arc-shaped grooves.

[0022] The second object of the utility model is to provide a circuit breaker, comprising the arc extinguishing system and contact system as described in any one of the above items.

[0023] Beneficial effects of the utility model:

[0024] The utility model provides an arc extinguishing system and a circuit breaker, the arc extinguishing system is used in conjunction with a contact system of the circuit breaker, the contact system includes a static contact, a main contact, an arc contact and a rotating shaft, the fixed end of the main contact and the fixed end of the arc contact are both connected to the rotating shaft, and the movable end of the main contact and the movable end of the arc contact can contact or separate from the static contact. The arc extinguishing system includes an arc extinguishing chamber and an arc isolation cover, wherein: the arc isolation cover is arranged between the arc extinguishing chamber and the rotating shaft, and the arc extinguishing chamber and the arc isolation cover are arranged to form an arc isolation area; the movable end of the arc contact moves in the arc isolation area, and the movable end of the main contact moves outside the arc isolation area; the arc isolation cover is provided with a blocking structure for blocking charged particles from escaping to the outside of the arc isolation area on one side close to the rotating shaft.

[0025] During use of the contact system, when the main contact and the static contact are disconnected, the generated arc is guided by the arc contact into the arc extinguishing chamber, and the generated arc is cut by the grid of the arc extinguishing chamber; since the movable end of the arc contact moves in the arc isolation area, the charged particles are isolated in the arc isolation area, avoiding the charged particles from spilling onto the main contact, thereby improving the current breaking ability of the arc extinguishing system; a blocking structure is provided on the side of the arc isolation cover close to the rotating shaft, and the blocking structure can block the gap between the arc isolation cover and the rotating shaft during the rotation of the rotating shaft. Therefore, the high-temperature charged particles in the arc isolation area retreating toward the rotating shaft cannot overflow from the gap between the arc isolation cover and the rotating shaft, thereby alleviating the back breakdown phenomenon existing in the existing products, and further improving the breaking performance and safety performance of the arc extinguishing system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1A schematic diagram of the internal structure of a circuit breaker provided in an embodiment of the utility model;

[0028] Figure 2 A schematic diagram of the front structure of the arc extinguishing system and the contact system provided in the embodiment of the utility model;

[0029] Figure 3 A schematic diagram of the three-dimensional structure of an arc shield provided in one embodiment of the utility model;

[0030] Figure 4 A schematic diagram of the position structure of the arc shield and the contact system provided in the embodiment of the utility model;

[0031] Figure 5 A schematic diagram of the three-dimensional structure of an arc shield provided in another embodiment of the utility model;

[0032] Figure 6 for Figure 1 Enlarged view at A.

[0033] icon:

[0034] 1-arc extinguishing chamber; 11-arc extinguishing chamber side wall; 12-grid group; 2-arc isolation cover; 21-blocking structure; 211-blocking plate; 2111-first opening; 212-first sealing strip; 22-arc isolation side plate; 221-arc chute; 23-arc isolation bottom plate; 24-pressure relief plate; 241-third opening; 25-connecting seat; 3-arc isolation area; 4-pressure relief area; 5-external leakage channel;

[0035] 100-contact system; 101-static contact; 102-main contact; 103-arc contact; 104-rotating shaft; 1041-housing; 1042-arc isolation cover plate; 1043-arc surface; 1044-first sealing groove;

[0036] 200- product housing; 201- installation cavity. DETAILED DESCRIPTION

[0037] The technical solution of the utility model will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0038] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0039] It should be noted that in the description of the present invention, the terms "connection" and "installation" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or connected through an intermediate medium; it can be a mechanical connection or an electrical connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] Reference Figure 1 and Figure 2 A contact system 100 of a circuit breaker includes a stationary contact 101, a main contact 102, an arc contact 103 and a rotating shaft 104. The fixed ends of the main contact 102 and the arc contact 103 are both connected to the rotating shaft 104, and the movable ends of the main contact 102 and the arc contact 103 can contact or separate from the stationary contact 101. During operation, the main contact 102 is mainly responsible for conducting current, and the arc contact 103 is mainly responsible for striking an arc; when the current is disconnected, the main contact 102 is disconnected from the stationary contact 101 before the arc contact 103, and the generated arc is guided to one place by the arc contact 103, which is convenient for concentrated extinguishing of the arc.

[0041] Based on the above contact system 100, an embodiment of the present invention provides an arc extinguishing system for use with the above contact system 100; Figure 1 and Figure 2 The arc extinguishing system comprises an arc extinguishing chamber 1 and an arc shield 2, wherein:

[0042] The arc isolation cover 2 is arranged between the arc extinguishing chamber 1 and the rotating shaft 104, and the arc extinguishing chamber 1 and the arc isolation cover 2 are arranged to form an arc isolation area 3; the movable end of the arc contact 103 moves in the arc isolation area 3, and the movable end of the main contact 102 moves outside the arc isolation area 3; a blocking structure 21 for blocking charged particles from escaping to the outside of the arc isolation area 3 is arranged on the side of the arc isolation cover 2 close to the rotating shaft 104.

[0043] During use of the contact system 100, when the main contact 102 and the static contact 101 are disconnected, the generated arc is guided by the arc contact 103 into the arc extinguishing chamber 1, and the generated arc is cut by the grid of the arc extinguishing chamber 1; since the movable end of the arc contact 103 moves in the arc isolation area 3, the arc is guided and isolated in the arc isolation area 3, thereby preventing the charged particles from spilling onto the main contact 102, thereby improving the current breaking ability of the arc extinguishing system; a sealing structure 21 is provided on the side of the arc isolation cover 2 close to the rotating shaft 104, and the sealing structure 21 can block the gap between the arc isolation cover 2 and the rotating shaft 104 during the rotation of the rotating shaft 104. Therefore, the high-temperature charged particles in the arc isolation area 3 retreating toward the rotating shaft 104 cannot overflow from the gap between the arc isolation cover 2 and the rotating shaft 104, thereby alleviating the back breakdown phenomenon existing in the existing products, and further improving the breaking performance and safety performance of the arc extinguishing system.

[0044] It should be noted that the number of the main contact 102 may be one or a plurality of main contacts 102 arranged side by side. When the number of the main contacts 102 may be multiple, the multiple main contacts 102 may all be arranged on the same side of the arc contact 103, or may be divided into two groups of main contact groups respectively arranged on opposite sides of the arc contact 103. The multiple main contacts 102 can divide the current passing through the contact system 100 into several currents in the same direction, thereby effectively improving the short-time withstand capability.

[0045] Reference Figure 2 and Figure 3 The arc isolation cover 2 includes two arc isolation side plates 22 arranged at intervals, each arc isolation side plate 22 extends from the arc extinguishing chamber 1 to the rotating shaft 104; the arc contact 103 is arranged between the two arc isolation side plates 22.

[0046] Specifically, the arc extinguishing chamber 1 includes two arc extinguishing chamber side walls 11 arranged at intervals and a grid sheet group 12 arranged between the two arc extinguishing chamber side walls 11. The two arc extinguishing chamber side walls 11 and the two arc isolating side plates 22 are arranged one by one. The corresponding set of arc extinguishing chamber side walls 11 and arc isolating side plates 22 are arranged flatly, and the grid sheet group 12, the two arc extinguishing chamber side walls 11 and the two arc isolating side plates 22 form an arc isolating area 3. The movable end of the arc contact 103 passes through the gap between the two arc isolating side plates 22 and extends into the gap between the two arc extinguishing chamber side walls 11. The main contact 102 is arranged on the side of the arc isolating side plate 22 away from the arc contact 103. During the rotation of the rotating shaft 104, the rotating shaft 104 drives the movable end of the arc contact 103 to move in the arc isolating area 3, and at the same time, the rotating shaft 104 drives the movable end of the main contact 102 to move outside the arc isolating area 3.

[0047] Continue to refer to Figure 2 and Figure 3The sealing structure 21 includes a sealing plate 211 with an arc-shaped structure, and a first opening 2111 is formed on the sealing plate 211 for the arc contact 103 to pass through; an arc-shaped surface 1043 is provided at one end of the rotating shaft 104 close to the arc isolation cover 2, and a gap between the sealing plate 211 and the arc-shaped surface 1043 is greater than or equal to 0 mm and less than or equal to 0.5 mm.

[0048] The provision of the blocking plate 211 increases the relative area between the arc shield 2 and the arc surface 1043 , making it almost impossible for charged particles to overflow from the gap between the blocking plate 211 and the arc surface 1043 .

[0049] Preferably, the gap between the blocking plate 211 and the arc surface 1043 is greater than or equal to 0.1 and less than or equal to 0.5 mm. This gap range can accommodate the processing and assembly errors of various workpieces while not hindering the movement of the rotating shaft 104 relative to the arc extinguishing chamber 1.

[0050] On the basis of the above structure, the two arc-isolating side plates 22 are connected to the blocking plate 211 at one side close to the rotating shaft 104 , and the first opening 2111 is provided between the two arc-isolating side plates 22 .

[0051] Reference Figure 4 and Figure 5 The sealing structure 21 includes a first sealing strip 212, and the rotating shaft 104 is provided with a first sealing groove 1044 for plugging and matching with the first sealing strip 212;

[0052] Alternatively, the sealing structure 21 includes a second sealing groove, and the rotating shaft 104 is provided with a second sealing strip for plugging and matching with the second sealing groove.

[0053] Take the blocking structure 21 including the first sealing strip 212 as an example; specifically, the first sealing groove 1044 extends along the surface of the rotating shaft 104 and is arranged on the rotating shaft 104 through; the first sealing strip 212 is arranged on the side of the arc shield 2 close to the rotating shaft 104 and is adapted to the structure of the first sealing strip 1044, the lower end of the first sealing strip 212 probes the static contact point on the static contact 101, and the upper end of the first sealing strip 212 probes the arc contact 103 in the current disconnection state. In the above structure, the gap between the arc shield 2 and the rotating shaft 104 is eliminated through the plug-in matching of the first sealing strip 212 and the first sealing groove 1044, further improving the sealing of the connection position of the arc shield 2 and the rotating shaft 104, ensuring that charged particles will not overflow from between the two.

[0054] It should be noted that the sealing structure 21 may only have a first sealing strip 212 but not a sealing plate 211; the sealing structure 21 may only have a sealing plate 211 but not a first sealing strip (or a second sealing groove); the sealing structure 21 may also have a sealing plate 211 and a first sealing strip 212 (or a second sealing groove) at the same time.

[0055] As an example, the sealing structure 21 does not have a sealing plate 211, and a first sealing strip 212 extends from one side of each arc-isolating side plate 22 close to the rotating shaft 104. A first sealing groove 1044 is recessed on the arc surface 1043, and the first sealing strip 212 can be slidably inserted in the first sealing groove 1044, so that during the rotation of the rotating shaft 104, the first sealing strip 212 slides in the first sealing groove 1044.

[0056] As another example, see Figure 5 The sealing structure 21 includes a sealing plate 211, and two first sealing strips 212 are arranged on one side of the sealing plate 211 close to the arc surface 1043, and the first opening 2111 is arranged between the two first sealing strips 212; two first sealing grooves 1044 are arranged on the arc surface 1043, and the two first sealing strips 212 correspond to the two first sealing grooves 1044 one by one, and the first sealing strips 212 can be slidably inserted into the corresponding first sealing grooves 1044.

[0057] As another example, the sealing structure 21 includes a sealing plate 211, and two second sealing grooves are provided on one side of the sealing plate 211 close to the arc surface 1043. Two second sealing strips are provided on the arc surface 1043. The two second sealing strips correspond to the two second sealing grooves one by one, and the second sealing strips can be slidably inserted in the corresponding second sealing grooves.

[0058] On the basis of the above structure, there is a gap of 0.1mm to 0.5mm between the first sealing groove 1044 and the first sealing strip 212 (or the second sealing groove and the second sealing strip). Taking the matching structure of the first sealing groove 1044 and the first sealing strip 212 as an example, there is a gap of 0.1mm to 0.5mm between the bottom wall of the first sealing groove 1044 and the first sealing strip 212, and there is a gap of 0.1mm to 0.5mm between the two groove side walls of the first sealing groove 1044 and the first sealing strip 212 respectively. By reserving a movable amount between the sealing groove and the sealing strip, the processing and assembly errors of each workpiece can be accommodated to prevent the arc shield 2 from hindering the movement of the rotating shaft 104 relative to the arc extinguishing chamber 1.

[0059] Continue to refer to Figure 4 In this embodiment, the rotating shaft 104 includes a housing 1041 and an arc-isolating cover plate 1042, and the arc-isolating cover plate 1042 covers an opening of the housing 1041 near one end of the arc-isolating cover 2;

[0060] The fixed ends of the main contact 102 and the arc contact 103 are both installed in the housing 1041 , and the arc isolation cover plate 1042 is provided with a second opening for the main contact 102 and the arc contact 103 to pass through.

[0061] On the basis of the above structure, the arc surface 1043 and the first sealing groove 1044 are both arranged on the arc isolation cover plate 1042 .

[0062] In the above structure, the arc isolation cover plate 1042 is used to block the opening of the shell 1041 near the arc isolation cover 2, thereby preventing charged particles from entering the shell 1041 and protecting the internal structure of the shell 1041 from being penetrated by the charged particles.

[0063] In other embodiments, the arc isolation cover plate 1042 may not be provided; in this embodiment, the arc surface 1043 and the first sealing groove 1044 are both provided on the housing 1041 .

[0064] Continue to refer to Figure 5 The arc isolation bottom plate 23 is connected between the bottoms of the two arc isolation side plates 22. The arc isolation bottom plate 23 can block the bottom of the arc isolation area 3 to prevent charged particles from overflowing from the gap at the bottom of the two arc isolation side plates 22; on the other hand, it plays a role in connecting the two arc isolation side plates 22, thereby improving the overall structural strength of the arc isolation cover 2.

[0065] Further, the arc shield 2 is fixed on the arc extinguishing chamber 1 or the product housing 200 of the circuit breaker. Optionally, the arc shield 2 can be fixed on the arc extinguishing chamber 1 or the product housing 200 of the circuit breaker by snap connection, screw connection, adhesive connection, or integral molding.

[0066] As an example, a corresponding set of arc-extinguishing chamber side walls 11 and arc-isolating side plates 22 are connected by snap-fitting, hinged connection, screw connection, or integral molding.

[0067] As another example, a connection seat 25 is provided on the arc isolation bottom plate 23 , and the connection seat 25 is snap-connected or screwed to the inside of the product housing 200 .

[0068] Both of the above examples can realize the fixed installation of the arc shield 2.

[0069] Continue to refer to Figure 4 and Figure 5 A plurality of arc-shaped grooves 221 are arranged on a surface of each arc-isolating side plate 22 away from the arc-isolating area 3, and a plurality of limiting protrusions are arranged on the main contact 102 close to the arc-isolating side plate 22. The plurality of arc-shaped grooves 221 are arranged in one-to-one correspondence with the plurality of limiting protrusions, and the limiting protrusions are slidably arranged in the corresponding arc-shaped grooves 221.

[0070] In the above structure, the arc-shaped slide groove 221 cooperates with the limiting protrusion to limit the moving track of the main contact 102, so as to prevent the main contact 102 from shifting or shaking, thereby improving the stability of the movement of the contact system 100 during the process of making and breaking current.

[0071] Reference Figure 5 and Figure 6 A pressure relief plate 24 is provided on the side of the arc shield 2 close to the arc extinguishing chamber 1, and a third opening 241 is provided on the pressure relief plate 24 for the arc contact 103 to pass through. In this embodiment, the pressure relief plate 24 is perpendicular to the two arc isolation side plates 22 and is provided between the main contact 102 and the arc extinguishing chamber 1; the two arc isolation side plates 22 are connected to the pressure relief plate 24 on one side close to the arc extinguishing chamber 1, and the third opening 241 is provided between the two arc isolation side plates 22.

[0072] Analyzing the above structure, the arc contact 103 is arranged between the two arc-isolating side plates 22, and the movable end of the arc contact 103 extends into the arc-extinguishing chamber 1 through the third opening 241; the main contact 102 is separated from the arc contact 103 by the arc-isolating side plate 22, and the main contact 102 is separated from the arc-extinguishing chamber 1 by the pressure relief plate 24. In the above structure, the arc-isolating side plate 22, the pressure relief plate 24 and the rotating shaft 104 enclose a relatively independent main contact active area, the fixed end of the main contact 102 is connected to the rotating shaft 104, and the movable end of the main contact 102 moves within the main contact active area; the joint between the arc-isolating side plate 22 and the rotating shaft 104 is sealed by a sealing structure 21, and the side of the arc-isolating side plate 22 close to the arc-extinguishing chamber 1 is connected to the pressure relief plate 24, and the main contact active area and the arc-isolating area 3 are separated by the sealing structure 21, the arc-isolating side plate 22 and the pressure relief plate 24 to ensure that charged particles do not contact the main contact 102.

[0073] Furthermore, the pressure relief plate 24 is spaced apart from the arc extinguishing chamber 1 , and a pressure relief area 4 is formed therebetween; the pressure relief area 4 is connected to the arc extinguishing area 3 .

[0074] If the pressure relief area 4 is not provided, the gas in the arc isolation area 3 cannot be dissipated in time because the arc isolation side plate 22 blocks the gas from dissipating to the two sides of the arc contact 103, causing the arc isolation area 3 to be in a high pressure state for a long time, thereby affecting the safety performance of the arc extinguishing system. The pressure relief area 4 can accommodate the gas that cannot be discharged in time in the arc isolation area 3, thereby relieving the pressure in the arc isolation area 3, so as to prevent the arc isolation area 3 from being in a high pressure state for a long time, thereby improving the safety performance of the arc extinguishing system.

[0075] Based on the above structure, continue to refer to Figure 6 , a mounting cavity 201 is provided in the product housing 200 of the circuit breaker, and the arc extinguishing system and the contact system 100 are both provided in the mounting cavity 201;

[0076] The opposite sides of the pressure relief plate 24 are respectively in contact with the two inner side walls of the installation cavity 201;

[0077] There is a gap between the arc extinguishing chamber 1 and the inner wall of the installation cavity 201, and the gap between the two forms an external leakage channel 5, and the two ends of the external leakage channel 5 are respectively connected to the pressure relief area 4 and the outside of the product housing 200. Specifically, the opposite sides of the pressure relief plate 24 are respectively abutted against the two inner walls of the installation cavity 201, and the pressure relief plate 24 divides the installation cavity 201 into a first cavity and a second cavity, wherein: the static contact 101 is arranged at the bottom of the arc extinguishing chamber 1, and a part is arranged in the first cavity, and the other part is arranged in the second cavity; the arc extinguishing chamber 1 is arranged in the first cavity, and the gap between the pressure relief plate 24 and the arc extinguishing chamber 1 forms a pressure relief area 4; the opposite sides of the arc extinguishing chamber 1 are respectively spaced from the two inner walls of the first cavity, thereby forming an external leakage channel 5 on the opposite sides of the arc extinguishing chamber 1, and each external leakage channel The two ends of the channel 5 are respectively connected to the pressure relief area 4 and the outside of the product housing 200; the fixed end of the arc contact 103 is arranged in the second cavity and connected to the rotating shaft 104, and the movable end of the arc contact 103 passes through the first opening 2111 on the sealing plate 211 and the third opening 241 on the pressure relief plate 24 in turn, extends into the first cavity and extends into the arc extinguishing chamber 1; two arc-isolating side plates 22, the rotating shaft 104 and the main contact 102 are arranged in the second cavity, and the two arc-isolating side plates 22 extend from the arc extinguishing chamber 1 to the rotating shaft 104, and the two arc-isolating side plates 22 are respectively arranged on opposite sides of the arc contact 103.

[0078] Figure 6 The arrow in the figure indicates the direction of airflow; continue to refer to Figure 6 The two arc-isolating side plates 22 and the arc-extinguishing chamber 1 are arranged to form an arc-isolating area 3, which is connected to the pressure relief area 4. The gas that cannot be discharged in time in the arc-isolating area 3 can enter the pressure relief area 4, thereby alleviating the phenomenon of excessive pressure in the arc-isolating area 3; the gas in the pressure relief area 4 can be discharged to the outside of the product housing 200 along the leakage channel 5, so as to prevent the gas carrying charged particles from being retained in the product housing 200 for a long time.

[0079] In the present application, the gas that cannot be discharged from the grid gap of the grid group 12 in time is discharged outwardly through the leakage channel 5, so that the arc isolation area 3 can be depressurized in time, thereby improving the safety performance of the arc extinguishing system; part of the gas carrying high-temperature charged particles is discharged outwardly through the leakage channel 5, which promotes the flow of gas around the arc extinguishing chamber 1, making the exhaust more convenient, and can quickly take away the heat inside the arc extinguishing chamber 1, reduce the overall temperature of the arc extinguishing chamber 1, and improve the breaking capacity of the arc extinguishing system; the setting of the leakage channel 5 can also change the direction of the airflow that reversely impacts the contact system 100, so that the airflow originally impacting the contact system 100 is discharged outwardly from the leakage channel 5, so as to avoid the problem of gas impacting the contact system 100 and causing damage to the contact system 100; in addition, since the leakage channel 5 itself has a certain length, the charged particles or arcs entering the leakage channel 5 will gradually cool down in the leakage channel 5, thereby improving the arc extinguishing effect.

[0080] Due to the processing and assembly errors of each workpiece during actual assembly, the two opposite sides of the pressure relief plate 24 may be difficult to form an abutment structure with the two inner side walls of the installation cavity 201, and a gap will be formed between the two, causing the charged particles in the arc isolation area 3 to enter the main contact active area through the gap. In response to this problem, in this embodiment, a slot is respectively provided on the two inner side walls of the installation cavity 201, and the two opposite sides of the pressure relief plate 24 are respectively inserted into the slots on the two inner side walls of the installation cavity 201 to form an abutment structure. By making the pressure relief plate 24 and the installation cavity 201 adopt a plug-in connection method, the gap between the pressure relief plate 24 and the inner side wall of the installation cavity 201 is eliminated, preventing charged particles from entering the main contact active area through the gap.

[0081] In summary, an arc extinguishing system provided in one embodiment of the present application includes an arc extinguishing chamber 1 and an arc extinguishing cover 2, wherein the arc extinguishing cover 2 is arranged between the arc extinguishing chamber 1 and the rotating shaft 104; the arc extinguishing cover 2 includes a blocking structure 21, two arc extinguishing side plates 22 arranged at intervals, an arc extinguishing bottom plate 23, a pressure relief plate 24 and a connecting seat 25, wherein:

[0082] The two arc-isolating side plates 22 and the arc-extinguishing chamber 1 are arranged to form an arc-isolating area 3. The movable end of the arc contact 103 moves in the arc-isolating area 3, and the movable end of the main contact 102 moves outside the arc-isolating area 3. The main contact 102 and the arc contact 103 are separated by the arc-isolating side plates 22 to prevent charged particles from spilling onto the main contact 102.

[0083] The blocking structure 21 is arranged on one side of the arc shield 2 close to the rotating shaft 104, and includes a blocking plate 211 and a first sealing strip 212 arranged on the blocking plate 211; the gap between the blocking plate 211 and the arc surface 1043 on the rotating shaft 104 is greater than 0.1 mm and less than or equal to 0.5 mm; the first sealing strip 212 is slidably inserted into the first sealing groove 1044 on the arc surface 1043; the blocking structure 21 can improve the sealing performance of the connection position between the arc shield 2 and the rotating shaft 104, and alleviate the phenomenon of charged particles breaking through from behind;

[0084] The pressure relief plate 24 is arranged on one side of the arc extinguishing chamber 1 of the arc extinguishing cover 2, and the gap between the pressure relief plate 24 and the arc extinguishing chamber 1 forms a pressure relief area 4; the pressure relief area 4 can accommodate the gas that has not been discharged in the arc extinguishing area 3 in time, thereby relieving the pressure of the arc extinguishing area 3;

[0085] The arc extinguishing system and contact system 100 are arranged in the installation cavity 201 on the product housing 200, and the gap between the arc extinguishing chamber 1 and the inner wall of the installation cavity 201 forms an external leakage channel 5; the gas in the pressure relief area 4 can be discharged to the outside of the product housing 200 along the external leakage channel 5;

[0086] One side of the two arc-isolating side plates 22 is connected to the pressure relief plate 24, and the other sides of the two arc-isolating side plates 22 are connected to the sealing plate 211. An arc-isolating bottom plate 23 is connected between the bottoms of the two arc-isolating side plates 22. A connecting seat 25 is provided at the bottom of the arc-isolating bottom plate 23. The arc-isolating cover 2 is clamped on the product housing 200 through the connecting seat 25. The arc-isolating cover 2 adopts an integrated molding processing method, which not only has a simple structure, but also has fewer processing and assembly steps.

[0087] In the above structure, the configuration of the arc shield 2 can prevent charged particles from scattering onto the main contact 102, thereby improving the breaking performance of the arc extinguishing system; and, the pressure relief area 4 and the external leakage channel 5 assist in discharging gas to the outside, thereby preventing the gas in the arc isolation area 3 from being retained for a long time, thereby improving the safety performance of the arc extinguishing system. In addition, the arc extinguishing system also has the advantages of compact structure, convenient disassembly and assembly, and stable movement of the main contact.

[0088] Another embodiment of the utility model provides a circuit breaker, referring to Figure 1 The circuit breaker includes a product housing 200, a contact system 100 and an arc extinguishing system as described in any of the above embodiments. The number of the contact system 100 and the arc extinguishing system is one or more, and the contact system 100 and the arc extinguishing system are arranged one by one; one or more installation cavities 201 are arranged in the product housing 200, and a corresponding group of contact systems 100 and the arc extinguishing system are arranged in each installation cavity.

[0089] The contact system 100, the arc extinguishing system and the number of the mounting cavities 201 are adjusted accordingly according to product specifications and usage requirements, and are not limited here.

[0090] The circuit breaker has at least all the technical effects of the above-mentioned arc extinguishing system, which will not be described in detail here.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. An arc extinguishing system, used in conjunction with a contact system (100) of a circuit breaker, the contact system (100) comprising a stationary contact (101), a main contact (102), an arc contact (103) and a rotating shaft (104), the fixed end of the main contact (102) and the fixed end of the arc contact (103) are both connected to the rotating shaft (104), and the movable end of the main contact (102) and the movable end of the arc contact (103) are both capable of contacting or separating from the stationary contact (101); characterized in that: The arc extinguishing system comprises an arc extinguishing chamber (1) and an arc shield (2), wherein: The arc isolation cover (2) is arranged between the arc extinguishing chamber (1) and the rotating shaft (104), and the arc extinguishing chamber (1) and the arc isolation cover (2) are arranged to form an arc isolation area (3); the movable end of the arc contact (103) moves in the arc isolation area (3), and the movable end of the main contact (102) moves outside the arc isolation area (3); and a blocking structure (21) for blocking charged particles from escaping to the outside of the arc isolation area (3) is arranged on one side of the arc isolation cover (2) close to the rotating shaft (104).

2. The arc extinguishing system according to claim 1, characterized in that: The blocking structure (21) comprises a blocking plate (211) in an arc-shaped structure, the blocking plate (211) being provided with a first opening (2111) for allowing the arc contact (103) to pass through; an arc-shaped surface (1043) is provided at one end of the rotating shaft (104) close to the arc isolation cover (2), and a gap between the blocking plate (211) and the arc-shaped surface (1043) is greater than or equal to 0 mm and less than or equal to 0.5 mm.

3. The arc extinguishing system according to claim 1, characterized in that: The sealing structure (21) comprises a first sealing strip (212), and the rotating shaft (104) is provided with a first sealing groove (1044) for plugging and matching with the first sealing strip (212); Alternatively, the sealing structure (21) comprises a second sealing groove, and the rotating shaft (104) is provided with a second sealing strip for plugging and cooperating with the second sealing groove.

4. The arc extinguishing system according to claim 1, characterized in that: The rotating shaft (104) comprises a shell (1041) and an arc isolation cover plate (1042), wherein the arc isolation cover plate (1042) covers an opening of the shell (1041) close to one end of the arc isolation cover (2); The fixed end of the main contact (102) and the fixed end of the arc contact (103) are both installed in the housing (1041), and the arc isolation cover plate (1042) is provided with a second opening for the main contact (102) and the arc contact (103) to pass through.

5. The arc extinguishing system according to claim 2, characterized in that: The arc isolation cover (2) comprises two arc isolation side plates (22) arranged at intervals, each of the arc isolation side plates (22) extending from the arc extinguishing chamber (1) toward the rotating shaft (104); and the arc contact (103) is arranged between the two arc isolation side plates (22).

6. The arc extinguishing system according to claim 5, characterized in that: One side of the two arc-isolating side plates (22) close to the rotating shaft (104) is connected to the blocking plate (211); And / or, an arc isolation bottom plate (23) is connected between the bottoms of the two arc isolation side plates (22).

7. The arc extinguishing system according to claim 1, characterized in that: The arc shield (2) is fixed on the arc extinguishing chamber (1) or on the product housing (200) of the circuit breaker.

8. The arc extinguishing system according to claim 1, characterized in that: A pressure relief plate (24) is provided on one side of the arc shield (2) close to the arc extinguishing chamber (1), and a third opening (241) for the arc contact (103) to pass through is provided on the pressure relief plate (24); The pressure relief plate (24) and the arc extinguishing chamber (1) are arranged at a distance, and a pressure relief area (4) is formed between the two; the pressure relief area (4) is connected to the arc extinguishing area (3); An installation cavity (201) is provided in the product housing (200) of the circuit breaker, and the arc extinguishing system and the contact system (100) are both arranged in the installation cavity (201); opposite sides of the pressure relief plate (24) are respectively in contact with two inner side walls of the installation cavity (201); There is a gap between the arc extinguishing chamber (1) and the inner wall of the installation cavity (201), and the gap between the two forms an external leakage channel (5), and the two ends of the external leakage channel (5) are respectively connected to the pressure relief area (4) and the outside of the product housing (200).

9. The arc extinguishing system according to claim 5, characterized in that: A plurality of arc-shaped slide grooves (221) are arranged on a surface of each arc-isolating side plate (22) away from the arc-isolating area (3), and a plurality of limiting protrusions are arranged on the main contact (102) close to the arc-isolating side plate (22). The plurality of arc-shaped slide grooves (221) are arranged in a one-to-one correspondence with the plurality of limiting protrusions, and the limiting protrusions are slidably arranged in the corresponding arc-shaped slide grooves (221).

10. A circuit breaker, characterized in that: The invention comprises an arc extinguishing system and a contact system (100) as claimed in any one of claims 1 to 9.

Images