Arc extinguishing device, starting switch and method

Abstract

The invention belongs to the field of starting switches, and discloses an arc extinguishing device, a starting switch and a method, and a composite arc extinguishing structure is formed by arranging an axially extending insulating cylinder on the moving path of a moving contact and a static contact, designing a continuous arc constraint unit on the inner wall and forming a heat dissipation groove in the outer wall. When an electric arc is generated, the inner wall restraining units force the electric arc to crawl along a spiral or broken line path through physical blocking, the electric arc length is remarkably prolonged, arc resistance is increased, and electric arc energy dissipation is accelerated; and meanwhile, the outer wall heat dissipation grooves quickly lead out the high temperature of the arc through air convection, and the arc column temperature and the ion concentration are reduced. The electric arc is fully stretched and cooled in a limited space through path extension, heat accumulation is continuously reduced through the heat dissipation grooves, and the electric arc cannot be reignited after current zero crossing is jointly promoted. The device effectively solves the problems of long arcing time and serious contact ablation of the original equipment, improves the large capacitive current breaking capacity, and eliminates the equipment stability and potential safety hazards caused by electric arc thermal erosion.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of starting switches, and particularly relates to an arc extinguishing device, a starting switch and a method. BACKGROUND

[0002] A pumped storage power station is a key facility in a power system with functions of peak regulation, frequency regulation, phase regulation, emergency accident handling and black start, and a starting switch is needed to realize the static frequency converter (SFC) starting or back-to-back (BTB) synchronous starting of a generator motor in the process of unit start-stop and working condition conversion, and the switch is a core special component of a complete set of switch equipment of the pumped storage power station. At present, the starting switch generally adopts air insulation design, resulting in large breaking distance of the breaking point, long and heavy moving conductor rod, and then slow moving speed of the moving contact; meanwhile, with the expansion of the construction scale of the pumped storage power station, the capacitive current of the loop where the starting switch is located is gradually increased from the initial 50 mA to 10 A, and the maximum capacitive breaking capacity of the existing starting switch structure is only 2 A, which is significantly different from the current operation demand.

[0003] From the equipment attribute, the starting switch belongs to the disconnector, and the designed breaking current is much smaller than that of the circuit breaker and the load switch, and no special arc extinguishing structure is configured. In the traditional working condition with small capacitive current, the slight ablation of the contact in the breaking process will not affect the overall performance; but when the capacitive current is increased to 10 A, the starting switch without the special arc extinguishing device faces serious arc extinguishing difficulty: the arc generated when the moving and static contacts are separated is delayed in extinguishing and has a prolonged existence time, and the long-time existence of the arc as high-temperature plasma will cause the continuous ablation of the hot plasma to the upstream, which will directly damage the performance stability of the equipment and even cause safety hazards.

[0004] Therefore, the current starting switch of the pumped storage power station has the problems of slow moving speed of the moving contact due to no special arc extinguishing structure and air insulation, the existing breaking capacity cannot meet the breaking demand of 10 A capacitive current, and the arc ablation affects the safety of the equipment. SUMMARY

[0005] The application provides an arc extinguishing device, a starting switch and a method, and the arc extinguishing device can solve the problems that the existing starting switch cannot meet the breaking demand of 10 A capacitive current and the arc ablation affects the safety of the equipment.

[0006] In order to achieve the above purpose, the application adopts the following technical content: An arc extinguishing device comprises an insulation cylinder. The insulation cylinder is arranged along the moving direction of the moving contact. One end of the insulation cylinder is connected to the static side shielding end, and the other end is inserted into the dynamic side shielding. The inner wall of the insulating cylinder is provided with a continuous arc constraint unit in the axial direction; The arc constraint unit is used to limit and prolong the creeping path of the arc; wherein the arc is generated by the moving and static contacts during the opening process; A plurality of heat dissipation grooves are formed on the outer wall of the insulating cylinder; the heat dissipation grooves are used to cool the heat generated by the arc inside the insulating cylinder through heat convection.

[0007] Further, one end of the insulating cylinder is fixedly connected with the static side shield through interference or bolt connection; The inner wall of the insulating cylinder is in gap fit with the moving contact; The arc constraint unit of the insulating cylinder adopts an umbrella-shaped structure.

[0008] Further, a circular baffle is arranged on the moving contact; The baffle, the inner wall of the insulating cylinder, the static side shield and the moving contact form a dynamic arc isolation area, which is used to prevent the arc from escaping in other directions during the opening process; The distance between the baffle and the cross section of the moving contact is greater than the depth of the moving contact inserted into the static side shield; The diameter of the baffle is at least 5mm greater than the diameter of the moving contact.

[0009] Further, the heat dissipation grooves are uniformly arranged along the circumference or arc of the insulating cylinder; a group of heat dissipation grooves is arranged corresponding to each arc constraint unit; and a preset distance is reserved between adjacent two heat dissipation grooves in the same group of heat dissipation grooves; The heat dissipation grooves adopt rectangular, circular or elliptical shapes.

[0010] Further, the combined effective length of the arc constraint units inside the insulating cylinder is greater than the distance between the moving contact and the static side shield; and the total length of the corresponding curve segment is at least 2 times the distance between the moving contact and the static side shield.

[0011] Further, the arc extinguishing device is applied to a horizontal type starting switch; The insulating cylinder adopts a first insulating cylinder, which specifically includes a first part and a second part; The first part is arranged in a whole circle structure, and the circumference is fixed with the static side shield; The inner surface of the second part is provided with a continuous arc constraint unit in an umbrella-shaped structure, and the outer surface is also in an umbrella-shaped structure; The second part is obtained by combining a plurality of semi-circular structures from one end close to the first part to one end away from the first part, and the diameters of the semi-circular structures from one end close to the first part to one end away from the first part are arranged in a tapering manner.

[0012] Further, the distance d between the nearest peak of the umbrella structure close to the first part and the surface of the first moving contact satisfies the following relationship: 5mm < d < 8mm. From the end close to the first part to the end away from the first part, the distance of the trough points of the umbrella structure from the center line increases in turn.

[0013] Further, the arc extinguishing device is applied to a vertical starting switch. The second insulating cylinder and the static side shield are fixed by bolts or interference fit to form vertical connection. The second insulating cylinder adopts a barrel structure. The inner and outer surfaces of the second insulating cylinder are provided with an umbrella structure to form the arc confinement unit. The inner wall of the second insulating cylinder is provided with a conical structure, and the inner diameter of the lower part is greater than that of the upper part. The inclination angle β of the heat dissipation groove satisfies the following relationship: 10° < β < 30°.

[0014] A method for using an arc extinguishing device, based on the above arc extinguishing device, comprising: The insulating cylinder is arranged along the movement direction of the moving contact, one end is fixed at the end of the static side shield, and the other end is inserted into the dynamic side shield; During the opening process, the moving contact and the static contact gradually separate, generating an arc, and the continuous arc confinement unit provided on the inner wall of the insulating cylinder is used to limit and extend the creeping path of the arc, thereby reducing the temperature of the arc. The heat dissipation groove is used to cool the heat generated by the arc inside the insulating cylinder by heat convection.

[0015] A starting switch, comprising a starting switch body and the above arc extinguishing device; the starting switch body is provided with the arc extinguishing device.

[0016] Compared with the prior art, the present application has the following beneficial effects: The application provides an arc extinguishing device, which comprises an axially extending insulating cylinder arranged on a moving path of a moving contact and a static contact, an inner wall of the insulating cylinder is designed with continuous arc restraining units, and an outer wall of the insulating cylinder is provided with heat dissipation grooves, so as to form a composite arc extinguishing structure. When an arc is generated due to opening of the moving contact and the static contact, the arc is forced to climb along a spiral or broken line path by the physical blocking of the arc restraining units on the inner wall, so that the arc length is significantly prolonged, the arc resistance is increased, and arc energy dissipation is accelerated; meanwhile, the arc high temperature is quickly led out by air convection through the heat dissipation grooves on the outer wall, so that the arc column temperature and ion concentration are reduced. The arc is actively inhibited by the synergistic effect of the two. The path prolonging makes the arc fully stretched and cooled in a limited space, and the heat accumulation is continuously reduced by the heat dissipation grooves, so that the arc cannot be reignited after the current is zero. The arc extinguishing device effectively solves the problems of long arc burning time and serious contact ablation of the original equipment due to the absence of arc extinguishing structure, improves the large capacity current breaking capacity, and eliminates the equipment stability and safety hazards caused by arc thermal erosion. Preferably, in the application, the umbrella-shaped restraining units increase the arc climbing resistance and strengthen the path prolonging effect; the interference / bolt fixation ensures the position stability of the insulating cylinder; and the inner wall gap is matched to consider the arc restraining and the moving freedom of the moving contact. While ensuring the structural reliability, the arc energy attenuation efficiency is maximized, and the risk of arc thermal erosion is reduced from the root.

[0017] Preferably, in the application, the baffle and the insulating cylinder form a dynamic isolation area, physically block the lateral escape path of the arc, and the size of the baffle is designed to ensure that the opening stroke is covered, so that the arc is forced to stretch and cool in the restraining unit at all times. The high-temperature plasma is completely prevented from diffusing to the non-target area, and the bypass ablation risk is eliminated. Preferably, in the application, the circumferentially distributed heat dissipation groove groups realize efficient heat dissipation in the whole region; the grouped restraining units form directional cooling channels, and the reserved spacing maintains the structural strength of the cylinder. The diversified groove shapes adapt to different heat dissipation needs, and the internal heat accumulation problem of the insulating cylinder is systematically solved.

[0018] Preferably, in the application, the combined length of the restraining units is designed to ensure that the arc is fully stretched to more than the critical extinguishing length, and the total length of the curved path is much longer than the contact spacing, so that the arc completes energy self-dissipation in a limited space. The bottleneck of the traditional switch arc extinguishing capacity is fundamentally broken through. Preferably, in the application, the tapered semicircle combined structure forms an arc compression channel, cooperates with the bidirectional umbrella-shaped units to accelerate the arc stretching, and the diameter gradient change guides the arc to gather in the core cooling area. The arc control path is optimized according to the characteristics of the horizontal switch, and the problem of uneven arc distribution caused by gravity is solved. Preferably, in the application, the peak and valley of the umbrella-shaped unit are precisely designed in combination with the contact gap, the arc restraining strength and the movement resistance are balanced, and the incrementally arranged wave troughs form a stepped arc stretching gradient. While ensuring smooth action of the moving contact, the arc burning energy is gradually reduced during the opening process. Preferably, in the present application, the conical inner wall is adapted to the vertical switch arc rising characteristics, the lower flared portion guides the arc to converge, and the upper tightened portion accelerates cooling; the inclined heat dissipation groove enhances the chimney effect to facilitate the discharge of hot air flow. The vertical working condition is optimized to improve the heat convection efficiency, and the difficulty of arc extinguishing caused by the natural upward floating of high-temperature plasma is solved. The present application also provides a method for using the arc extinguishing device. Based on the arc extinguishing device, the method forces the arc path to be lengthened by the inner wall continuous arc constraint unit when the switch is opened by axially fixing the insulating cylinder to the static side shield and inserting it into the dynamic side shield. When the arc is generated by the separation of the dynamic and static contacts, the arc constraint unit forces the arc to climb along a spiral or zigzag trajectory, significantly lengthens the arc length to increase the resistance and energy consumption, and at the same time, reduces the heat aggregation in the arc temperature core area. The outer wall heat dissipation groove continuously leads the heat inside the insulating cylinder away by air heat convection, forming a dynamic cooling cycle. The two work together to accelerate the arc energy attenuation and inhibit the diffusion of hot plasma, and finally make the arc extinguish quickly when the current is zero. Thus, the problems of long arc burning time, hot ion backflow, and component ablation caused by the original equipment without arc extinguishing structure are completely solved, the large capacity current breaking capacity is significantly improved, and the equipment stability hidden danger and safety risk are eliminated. The present application also provides a starting switch, which forms a composite arc extinguishing structure by integrating the above-mentioned arc extinguishing device in the starting switch body. In specific implementation, the insulating cylinder is arranged axially along the dynamic contact movement axis, the static end is fixed to the shield, and the dynamic end is inserted into the dynamic side shield. The inner wall continuous constraint unit and the external heat dissipation groove constitute a cooperative arc extinguishing mechanism. After the arc is generated by the opening of the switch, the constraint unit forces the arc to climb along a spiral or zigzag path, greatly lengthens the arc length to increase the resistance and energy consumption, and at the same time, reduces the arc core temperature. The heat dissipation groove continuously leads the high-temperature plasma heat inside the insulating cylinder away by air convection, and inhibits heat aggregation. The two work together to accelerate the arc energy attenuation and block the path of hot ion flowing upstream, so that the arc is extinguished quickly when the current is zero. Finally, the problems of long arc burning time, contact ablation, and hot ion backflow damaging components caused by the original equipment without arc extinguishing structure are completely solved, the large capacity current breaking capacity is significantly improved, and the long-term stable operation and safety of the equipment are ensured. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 A structure schematic diagram of an arc extinguishing device provided for an embodiment of the present application; Figure 2 A structure schematic diagram of a horizontal starting switch including an arc extinguishing device provided for an embodiment of the present application; Figure 3 A structure schematic diagram of an arc constraint unit provided for an embodiment of the present application; Figure 4 A structure schematic diagram of a first insulating cylinder provided for an embodiment of the present application; Figure 3 A cross-sectional view in A-A direction; Figure 5 A structure schematic diagram of a first insulating cylinder provided for an embodiment of the present application; Figure 6 Structure diagram of another view of the first insulating cylinder provided for the embodiment of the present application; Figure 7 Closing position diagram of the horizontal starting switch provided for the embodiment of the present application; Figure 8 Diagram of the movement of the moving contact of the horizontal starting switch to a certain intermediate time position provided for the embodiment of the present application; Figure 9 Opening position diagram of the horizontal starting switch provided for the embodiment of the present application; Figure 10 Structure diagram of the baffle provided for the embodiment of the present application; Figure 11 Structure diagram of the vertical starting switch including the arc extinguishing device provided for the embodiment of the present application; Figure 12 Closing position diagram of the vertical starting switch provided for the embodiment of the present application; Figure 13 Diagram of the movement of the moving contact of the vertical starting switch to a certain intermediate time position provided for the embodiment of the present application; Figure 14 Opening position diagram of the vertical starting switch provided for the embodiment of the present application; Figure 15 Structure diagram of the second insulating cylinder provided for the embodiment of the present application; Figure 16 Structure diagram of the heat dissipation groove of the second insulating cylinder provided for the embodiment of the present application.

[0020] Reference signs: 1, fixed support; 2, first supporting insulator; 3, first conductor; 4, first shielding assembly; 4.1, first arc contact; 4.2, first main contact; 4.3, first shielding cover; 5, first insulating cylinder; 6, first moving contact; 7, second shielding assembly; 7.1, second shielding cover; 7.2, fixed support; 8, third shielding assembly; 8.1, third shielding cover; 8.2, second main contact; 9, second conductor; 10, second supporting insulator; 11, moving contact transmission assembly; 12, baffle; 101, third conductor; 102, fourth shielding assembly; 1021, fourth shielding cover; 1022, third main contact; 1023, second arc contact; 103, second moving contact; 104, fifth shielding assembly; 1041, fifth shielding cover; 1042, fourth main contact; 105, fourth conductor; 106, second insulating cylinder; 21, first part; 22, second part; 23, umbrella structure; 24, heat dissipation groove. DETAILED DESCRIPTION

[0021] In order to make the technical problems solved by the present application, technical solutions and beneficial effects clearer, the following specific embodiments are used to further describe the present application in detail. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0022] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application and not all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0024] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0025] The technical terms related to the present application are explained as follows: Arc extinguishing grid device is widely used in low-voltage electrical field: it is an important device for extinguishing arc in electrical engineering, mainly suitable for low-voltage system (commonly used in 380V-690V), especially commonly used in circuit breaker, contactor and other switch devices. Arc extinguishing grid is usually arranged by a series of metal grid plates (commonly used cold-rolled steel plates plated with copper or zinc, with a thickness of about 1.5-2mm) insulated from each other at a certain interval (about 2-2.5mm). These grid plates are usually fixed in an arc extinguishing cover or arc extinguishing chamber made of high-temperature-resistant insulating materials such as asbestos cement, porcelain clay or special engineering plastics. Some arc extinguishing grids also integrate magnetic blow coils to more effectively blow the arc into the grid plate gap by generating a magnetic field. Regular inspection and cleaning are required during use: to avoid serious carbon deposition (carbonization to form conductive bridge) or rusting of the grid plates, and to prevent the grid plates from falling off or deforming.

[0026] Working principle: the core working principle of arc extinguishing grid is: based on the near-cathode effect and arc splitting.

[0027] First, split long arc into short arc: when the contacts are separated to generate an arc, the arc is quickly elongated and introduced into the arc extinguishing grid composed of multiple metal grid plates under the action of electromagnetic force or electric force. A long arc is split into multiple short arc segments in series.

[0028] Second, near-cathode effect arc extinguishing: in an alternating current circuit, the current will pass zero once every half cycle. At the moment of current zero, all short arcs are extinguished at the same time. According to the near-cathode effect, a dielectric strength (initial dielectric strength) of 150-250V will be immediately formed near the cathode of each short arc. If the sum of the initial dielectric strengths of all series short arcs exceeds the applied voltage between the contacts, the arc cannot be re-ignited, thereby being extinguished.

[0029] Third, cooling and deionization: the metal grid has good thermal conductivity, can absorb arc heat and reduce temperature. At the same time, the grid surface can adsorb charged particles, accelerate the recombination (combination of positive and negative charges) and diffusion of charged particles, thereby enhancing the deionization effect and helping to extinguish the arc.

[0030] As described in the background, during the breaking process of the starting switch, when the moving and static contacts are just separated, an arc will be generated between the moving and static contacts. As the moving contact moves, the distance between the moving and static contacts increases, and since the breaking current increases, the arc extinguishing will be relatively delayed or difficult, and the time of the arc existing will also be longer. During the arc breaking process, since the arc is a high-temperature plasma, the hot plasma will flow upstream. When the arc extinguishing is difficult, the long-time existence of the arc may ablate the components, and when the ablation accumulates to a certain extent, it may affect the overall safety performance of the equipment.

[0031] To solve the above problems, the embodiment provides an arc extinguishing device. The arc extinguishing device is applied to a starting switch with increased capacitive current. According to the existing actual switch structure, the arc burning time is increased, and an insulating cylinder is used to constrain the arc. The inner surface of the insulating cylinder is designed in a umbrella shape to assist in lengthening the arc. A plurality of open slots are designed on the insulating cylinder to flow hot gas during the breaking process.

[0032] The arc extinguishing device provided by the embodiment will be further described below with reference to the drawings: Embodiment 1 As a preferred scheme of the present application, as shown in Figure 1 The embodiment provides an arc extinguishing device. The arc extinguishing device is applied to a starting switch arranged horizontally, and a first insulating cylinder 5 is arranged between the breaking points of the starting switch body. The center line of the first moving contact 6, the first insulating cylinder 5 and the static side shield is in a horizontal direction. One end of the first insulating cylinder 5 is fixed to the static side shield, and the other end extends into the moving side shield to form an arc isolation area. When the breaking current increases, the arc burning time increases. In order to prevent the arc from burning for a long time and ablate other parts, thereby affecting the overall performance of the product.

[0033] In this embodiment, the first insulating cylinder 5 is composed of two parts. The first part 21 is a whole circle structure, which is used to be fixed with the static side shield. The fixing can be achieved by bolt or interference fit. For the bolt fixing, a through hole is provided on the circumference of the first part 21, and a threaded hole is provided on the circumference of the static side shield. For the interference fit, the inner circumference of the first part 21 is matched with the outer circumference of the static side shield. The second part 22 is a non-whole circle structure, which has the following characteristics: As shown in Figure 5 and Figure 6 , the second part 22 of the first insulating cylinder 5 is provided with an umbrella-shaped structure 23 on the inner and outer surfaces of the insulating cylinder, which increases the creepage distance of the two side cylinder walls. The umbrella-shaped structure 23 can also have other shapes such as rectangle and triangle.

[0034] The umbrella-shaped structure 23 is designed with multiple heat dissipation grooves 24, which can be in any shape such as rectangle, circle and ellipse. The heat dissipation grooves 24 are used to dissipate the heat generated by the arc burning during the opening process.

[0035] As shown in Figure 3 , the angle between the inclined line of the second part and the center line is α, so that the area of the insulating cylinder from the top view is close to the area of the first part of the insulating cylinder, and gradually decreases away from the first part of the insulating cylinder, i.e. M1>M2>M3>M4…. In this way, not only can the arc be continuously isolated and constrained in the second half of the arc, but also a part of the top space can be reserved, so that the heat generated by the arc after the arc burning time is lengthened can be quickly exchanged with the surrounding air.

[0036] The length F of the effective distance of the first insulating cylinder 5 is greater than the distance E between the first moving contact 6 of the starting switch and the static side shield, so that the lower area of the first insulating cylinder 5 and the first moving contact 6 and the static side shield can form an effective isolation area for the arc.

[0037] Further, the total length of the corresponding curve segment on the surface of the first moving contact 6 within the effective distance F is at least 2E, so that the arc adhering to the inner surface of the insulating cylinder can be assisted to lengthen.

[0038] The distance d between the peak and valley of the umbrella-shaped structure closest to the static side shield on the inner surface of the first insulating cylinder 5 and the surface of the first moving contact 6 is 5mm

[0039] As shown in Figure 4 , the distance from the center line of the valley point of the umbrella-shaped inner surface of the first insulating cylinder 5 increases in turn, dl < d2 < d3 < d4 …, on the one hand, the distance between the adjacent two umbrella-shaped top points can be increased, so that the shortest burning path of the arc is lengthened when reaching the adjacent two valleys of the umbrella. In combination with Figure 7 , Figure 8 and Figure 9 , on the other hand, as the first moving contact 6 continues to move in the opening direction, the arc generated on the first moving contact 6 moves following the movement of the first moving contact 6, so that the heat generated in the area near the first moving contact 6 is dissipated to different areas as it moves, so that the temperature of the arc on the first moving contact 6 will be relatively reduced, and the arc has the possibility of being extinguished at any moment in this area. This is conducive to the arc moving to the top as soon as possible, and the heat generated flows out of the heat exchange hole to form a thermal convection to speed up heat dissipation.

[0040] Further, during the opening movement of the first moving contact 6, the peaks and valleys of each umbrella can be effectively utilized, so that the arc can be attached along the umbrella shape, which is more conducive to arc extinction.

[0041] In this embodiment, the material of the first insulating cylinder 5 can be selected from polytetrafluoroethylene, epoxy resin or epoxy glass cloth board and other insulating materials.

[0042] For example, as shown in Figure 10 , in order to achieve the traction and control of the arc, a circular baffle 12 is arranged on the first moving contact 6, the material of the baffle 12 is insulating material, the diameter of the baffle 12 is at least greater than the diameter of the moving contact by 5mm or more, and the distance from one end of the baffle 12 to the cross section of the first moving contact 6 is T, which is greater than the insertion depth P of the first moving contact 6 into the static side shield, so as to ensure that the moving contact can be smoothly closed to the bottom. When the moving contact moves in the opening direction, on the one hand, the arc on the moving contact can be limited in a fixed area, i.e. the end area of the first moving contact 6, so as to prevent the arc from escaping to other parts of the first moving contact 6 and burning other parts. On the other hand, the baffle 12 can cooperate with the first insulating cylinder 5 to control the arc in the isolation area.

[0043] Embodiment 2: As another preferred scheme of the present application, as shown in Figure 11As shown, the embodiment also provides another arc extinguishing device applied to a vertical start switch, that is, the center line of the second moving contact 103, the second insulating cylinder 106, and the static side shield is along the vertical direction. The static side shield (the fourth shield assembly 102) is above, the second moving contact 103 is below, and the second insulating cylinder 106 is between the two. The second insulating cylinder 106 and the static side shield can be fixed by bolts or interference fit. The second moving contact 103 can be arranged at the lowermost end. Due to the arrangement characteristics, the arc between the static side arc contact and the second moving contact 103 can exist at any point along the circumferential surface. In order to effectively control the arc, the second insulating cylinder 106 in the embodiment is arranged as a barrel-shaped structure as a whole.

[0044] For example, the inner and outer surfaces of the second insulating cylinder 106 are provided with umbrella-shaped structures 23 to increase the creepage distance of the two side cylinder wall surfaces. Other shapes such as rectangles and triangles can also be used in addition to umbrella shapes.

[0045] The inner wall of the second insulating cylinder 106 adopts a conical structure, and the inner diameter of the lower part is larger than that of the upper part. The internal umbrella-shaped structure is arranged along the normal structure of the conical surface, so that the burning arc can move into two adjacent umbrella-shaped regions during the breaking process, thereby assisting in lengthening the arc.

[0046] The distance between the inner surface of the second insulating cylinder 106 and the moving contact surface is 5mm < Q < 8mm, so as to ensure that the minimum electrical gap is met, and the distance between the arc is relatively close, so that the burning arc can easily enter between two adjacent umbrella-shaped structures.

[0047] As shown in Figure 15 In the embodiment, heat dissipation grooves 24 are arranged circumferentially on the second insulating cylinder 106. The heat dissipation grooves 24 in the same horizontal plane are discontinuous annular structures, and a certain distance is left between adjacent heat dissipation grooves 24 to support the overall structural strength of the insulating cylinder.

[0048] For example, as shown in Figure 16 As shown, the inclination angle β of the heat dissipation groove 24 satisfies the following relationship: 10° < β < 30°. The setting of the inclination angle makes it easier for the heat generated by the arc burning to flow out of the heat dissipation groove 24.

[0049] In combination with Figure 12 , Figure 13 and Figure 14 As shown, the arc extinguishing device provided by the embodiment has the same working principle and use method as that of the first embodiment.

[0050] Therefore, the embodiment provides an arc extinguishing device, which has the following advantages: First, the arc extinguishing device forms an isolation for the arc by setting the insulating cylinder to prevent the arc from ablation to other components and affect the overall safety of the equipment Second, the high-temperature arc will flow in the upstream direction, and when reaching the inner surface of the insulating cylinder, it cannot cross the isolation layer of the insulating cylinder, and the inner surface of the insulating cylinder is provided with an umbrella-shaped structure, and the high-temperature arc adheres to the umbrella-shaped structure, which forcibly lengthens the arc to reduce the temperature of the arc, so that the arc is easily extinguished Third, a plurality of open slots are designed on the insulating cylinder, and during the arc extinguishing process, the high-temperature gas generated will flow through the open slots, thereby forming a heat convection in the isolation area wrapped by the insulating cylinder, which is beneficial to heat dissipation in this area, thereby making the arc easily extinguished.

[0051] Example 3: Based on the above arc extinguishing device, as shown in Figure 2 The embodiment also provides a starting switch, i.e., a horizontal starting switch, which is composed of a first conductor 3, a first shielding assembly 4, a first insulating cylinder 5, a first moving contact 6, a second shielding assembly 7, a third shielding assembly 8, and a second conductor 9, etc. components, wherein the first shielding assembly 4 includes a first arc contact 4.1, a first main contact 4.2, and a shielding cover 4.3. The second shielding assembly 7 is composed of a second shielding cover 7.1 and a fixed support 7.2. The third shielding assembly 8 is composed of a third shielding cover 8.1 and a second main contact 8.2. In order to achieve the implementation effect of the embodiment, the first insulating cylinder 5 is fixed on the first shielding assembly 4. The first moving contact 6 moves horizontally to complete the opening and closing operation.

[0052] Example 4: Based on the above arc extinguishing device, as shown in Figure 11 The embodiment also provides another starting switch, i.e., a vertical starting switch, which is composed of a third conductor 101, a fourth shielding assembly 102, a second moving contact 103, a fifth shielding assembly 104, a fourth conductor 105, and a second insulating cylinder 106. The fourth shielding assembly 102 is composed of a fourth shielding cover 1021, a third main contact 1022, and a second arc contact 1023. The fifth shielding assembly is composed of a fifth shielding cover 1041 and a fourth main contact 1042. The second moving contact 103 moves vertically up and down to complete the opening and closing operation. In order to achieve the implementation effect of the embodiment, the second insulating cylinder 106 is fixed on the fourth shielding assembly 102. In the embodiment, the insulating material baffle 12 on the second moving contact 103 helps to change the airflow in the insulating cylinder, which is beneficial to heat convection exchange.

[0053] In summary, the present application provides an arc extinguishing device, a starting switch and a method, which has the following advantages compared with the existing starting switch: The application integrates an insulating cylinder arc extinguishing structure in a starting switch, which is arranged along the moving direction of the moving contact and connected with the static and dynamic side shields to form a cooperative arc extinguishing mechanism: the inner wall continuous arc constraint unit forcibly extends the arc crawling path and increases the resistance to accelerate energy dissipation; the outer wall heat dissipation groove efficiently exports the arc high temperature ion plasma heat through heat convection; the baffle isolation design blocks the arc escape, and the umbrella structure and the tapered / cone cylinder body adapt to the horizontal or vertical installation conditions. The whole scheme breaks through the limitation of the traditional switch without a special arc extinguishing structure through the synergistic effect of physical constraint and dynamic cooling: the arc is fully stretched and cooled to be quickly extinguished, the contact ablation and thermal ion backflow damage component problems caused by arc delay are completely eliminated, the large capacity current breaking capacity is significantly improved, and the long-term stability and operation safety of the equipment are fundamentally guaranteed.

[0054] The above embodiment is only one of the implementation manners of the technical scheme of the application, and the scope of the application claimed by the application is not limited to the embodiment, but also includes any changes, substitutions and other implementation manners easily thought of by those skilled in the art within the technical scope disclosed by the application.

Claims

1. An arc extinguishing device, characterized in that The insulating cylinder includes an insulating cylinder body and a plurality of arc-restraining units arranged on the inner wall of the insulating cylinder body. The insulating cylinder is arranged along the movement direction of the moving contact. One end of the insulating cylinder is connected to the static side shielding end, and the other end is inserted into the moving side shielding. The inner wall of the insulating cylinder is provided with continuous arc-restraining units in the axial direction. The arc-restraining units are used to limit and lengthen the creeping path of the arc, wherein the arc is generated by the moving and static contacts during the opening process. A plurality of heat dissipation grooves (24) are arranged on the outer wall of the insulating cylinder, and the heat dissipation grooves (24) are used to cool the heat generated by the arc inside the insulating cylinder through heat convection.

2. An arc extinguishing device according to claim 1, characterized in that One end of the insulating cylinder is fixedly connected to the static side shielding through interference or bolt connection. The inner wall of the insulating cylinder is in gap cooperation with the moving contact. The arc-restraining units of the insulating cylinder adopt an umbrella-shaped structure (23).

3. An arc quenching device according to claim 2, characterized in that A circular baffle (12) is arranged on the moving contact. The baffle (12), the inner wall of the insulating cylinder, the static side shielding and the moving contact form a dynamic arc isolation area, which is used to prevent the arc from escaping in other directions during the opening process. The distance between the baffle (12) and the cross section of the moving contact is greater than the depth of the moving contact inserted into the static side shielding. The diameter of the baffle (12) is at least 5 mm greater than the diameter of the moving contact.

4. An arc quenching device according to claim 1, characterized in that The heat dissipation grooves (24) are uniformly arranged along the circumference or arc of the insulating cylinder; a group of heat dissipation grooves (24) are arranged corresponding to each arc-restraining unit; and a preset distance is reserved between adjacent two heat dissipation grooves (24) in the same group. The heat dissipation grooves (24) adopt a rectangular, circular or elliptical shape.

5. An arc quenching device according to claim 1, characterized in that The combined effective length of the arc-restraining units inside the insulating cylinder is greater than the distance between the moving contact and the static side shielding; and the total length of the corresponding curve segment is at least 2 times the distance between the moving contact and the static side shielding.

6. An arc quenching device according to claim 1, characterized in that The arc extinguishing device is applied to a horizontal type starting switch. The insulating cylinder adopts a first insulating cylinder (5), which specifically includes a first part (21) and a second part (22). The first part (21) is arranged in a whole circle structure, and the circumference is fixed to the static side shielding. The inner surface of the second part (22) is provided with continuous arc-restraining units in an umbrella-shaped structure (23), and the outer surface is also in an umbrella-shaped structure (23). The second part (22) is obtained by combining a plurality of semi-circular structures from one end close to the first part (21) to one end away from the first part (21), and the diameters of the semi-circular structures gradually decrease from one end close to the first part (21) to one end away from the first part (21).

7. An arc quenching device according to claim 6, characterized in that The distance d between the peak and valley of the nearest umbrella-shaped structure (23) close to the first part (21) and the surface of the first moving contact (6) satisfies the following relationship: 5 mm < d < 8 mm. The distance of the trough points of the umbrella-shaped structure (23) from the center line gradually increases from one end close to the first part (21) to one end away from the first part (21).

8. An arc quenching device according to claim 1, characterized in that The arc extinguishing device is applied to a vertical type starting switch. The second insulating cylinder (106) and the static side shielding are fixed by bolts or interference fit to form vertical connection. The second insulating cylinder (106) adopts a barrel-shaped structure. The inner and outer surfaces of the second insulation cylinder (106) are provided with umbrella-shaped structures (23) to form the arc confinement unit; The inner wall of the second insulation cylinder (106) is provided with a conical structure, and the inner diameter of the lower part is larger than that of the upper part; The inclination angle β of the heat dissipation groove (24) satisfies the following relationship: 10°<β<30°.

9. A method of using an arc extinguishing device according to any one of claims 1-8, characterized in that The application relates to an arc extinguishing device for a circuit breaker. The insulation cylinder is arranged along the movement direction of the moving contact, one end of the insulation cylinder is fixed to the shielding end of the static side, and the other end of the insulation cylinder is inserted into the shielding of the moving side; During the opening process, the moving contact and the static contact are gradually separated to generate an arc, the continuous arc confinement unit arranged on the inner wall of the insulation cylinder is used to limit and prolong the creeping path of the arc, and the temperature of the arc is reduced; The heat dissipation groove (24) is used to cool the heat generated by the arc in the insulation cylinder through a heat convection mode.

10. A start switch characterized by The application relates to an arc extinguishing device for a circuit breaker.

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