CN219842909U - Arc extinguishing chamber and circuit breaker - Google Patents

Abstract

The utility model provides an explosion chamber and circuit breaker, the circuit breaker includes the explosion chamber, the explosion chamber includes two arc extinguishing components of relative setting to and set up the striking piece between two arc extinguishing components, the striking piece include with two striking structures of two arc extinguishing components complex respectively, two striking structures include striking portion and lower striking portion respectively, the last striking portion of two striking structures sets up between two arc extinguishing components, and the last striking portion of two striking structures links to each other, the lower striking portion of two striking structures stretches to one side of corresponding arc extinguishing components respectively, wherein at least one the striking structure including connect the tensile portion between striking portion and lower striking portion above that, tensile portion includes two at least tensile pieces of relative setting, and connects the connection piece between two at least tensile pieces enclose into tensile space between connection piece and the two tensile pieces that link to each other, can increase electric arc moving distance and contact area with the striking piece.

Description

Arc extinguishing chamber and circuit breaker

Technical Field

The utility model relates to the field of piezoelectric devices, in particular to an arc extinguishing chamber and a circuit breaker.

Background

The arc-extinguishing chamber is used as an important component of the circuit breaker, and the arc-extinguishing capacity of the arc-extinguishing chamber directly determines the breaking overload and short-circuit current performance of the whole circuit breaker. In an ac system, the extinction of an arc is relatively easy because the ac has zero crossings, whereas the dc has no zero crossings, and the extinction of an arc is relatively difficult. At present, plastic-case circuit breaker products are continuously developed towards the directions of small volume and high performance, so that in order to meet the high-voltage breaking requirement of the two-pole DC1000V, DC V of the plastic-case circuit breaker in a photovoltaic power distribution system, how to improve the arc extinguishing capability of an arc extinguishing chamber becomes a problem which needs to be solved by technicians.

Disclosure of Invention

The utility model aims to overcome the defects of the prior art and provide the arc extinguishing chamber with simple structure and high reliability.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the utility model provides an explosion chamber, includes two arc extinguishing components that set up relatively to and set up the striking spare between two arc extinguishing components, the striking spare include with two arc extinguishing components are two striking structures of complex respectively, two striking structures include striking portion and lower striking portion respectively, the last striking portion setting of two striking structures is between two arc extinguishing components, and the last striking portion of two striking structures links to each other, the lower striking portion of two striking structures stretches to one side of corresponding arc extinguishing components respectively, wherein at least one the striking structure including connect the tensile portion between striking portion and lower striking portion above that, tensile portion includes two at least tensile pieces of relative setting, and connect the connection piece between two at least tensile pieces enclose into tensile space between connection piece and the two tensile pieces that link to each other.

Preferably, the stretching part comprises a plurality of stretching sheets, the stretching sheets enclose a stretching space and a cooling space which are alternately arranged through the connecting sheets, and the opening direction of the cooling space is opposite to the stretching space.

Preferably, the plurality of stretching sheets are respectively arranged in parallel with the arc extinguishing grid sheets of the arc extinguishing assembly, the connecting sheets comprise a front connecting sheet and a rear connecting sheet, the rear connecting sheet is used for connecting adjacent stretching sheets and enclosing into the stretching space, and the front connecting sheet is used for connecting stretching sheets adjacent to the stretching space and enclosing into the cooling space.

Preferably, the plurality of stretching sheets are respectively and vertically arranged with the arc extinguishing grid sheets of the arc extinguishing assembly, the connecting sheets comprise a lower connecting sheet and an upper connecting sheet, the upper connecting sheet is used for connecting adjacent stretching sheets and enclosing into a stretching space with an opening facing the lower arc striking part, and the lower connecting sheet is used for connecting the stretching sheets adjacent to the stretching space and enclosing into a cooling space with the opening facing the upper arc striking part.

Preferably, the arc striking piece is integrally bent, and the connecting piece is in a cambered surface shape; the two arc striking structures of the arc striking piece are both provided with the stretching part.

Preferably, the distance from the upper arc striking part to the lower arc striking part of the two arc striking structures gradually increases along the direction away from the corresponding arc extinguishing assembly, and an arc striking tip is formed at the connecting position of the upper arc striking parts of the two arc striking structures.

Preferably, the distance from the lower arc striking part to the corresponding arc extinguishing assembly is a, the minimum distance from the stretching part to the corresponding arc extinguishing assembly is d, and both a and d are larger than the minimum distance c from the moving contact to the arc striking structure; the arc extinguishing device is characterized by further comprising two arc striking plates which are respectively matched with the two arc extinguishing assemblies, wherein the minimum distance from the two arc striking plates to the arc striking structure is b, b is greater than a, and b is greater than d.

Preferably, an inlet is arranged above the middle of the arc extinguishing chamber, namely, an inlet is arranged above the arc striking piece between the two arc extinguishing components, outlets which are respectively matched with the two arc extinguishing components are arranged at two ends of the arc extinguishing chamber, and a first arc isolating grid and a second arc isolating grid are respectively arranged at the outlets.

Preferably, the stretching part includes at least four stretching sheets forming a plurality of stretching spaces and a plurality of cooling spaces.

According to the arc extinguishing chamber, the stretching part is additionally arranged on the arc striking structure between the two arc extinguishing components, and the U-shaped stretching space is formed by the connecting piece on the stretching part and at least two stretching pieces, so that the smooth air flow can be ensured, the moving distance of the arc can be increased, the contact area between the arc and the arc striking piece 50 can be increased, the arc needs to enter the stretching space and move along the stretching pieces and the connecting piece, the arc in the two arc extinguishing components is further prolonged, and the arc extinguishing capability of the whole arc extinguishing chamber is effectively improved.

The circuit breaker comprises a fixed contact, a moving contact, a rotating shaft system and an arc-extinguishing chamber, wherein the rotating shaft system is positioned above the arc-extinguishing chamber, the moving contact is positioned between the rotating shaft system and the arc-extinguishing chamber, and the rotating shaft system can drive the moving contact to contact with the fixed contact.

Preferably, the circuit breaker further comprises a housing, the housing comprises two side walls which are oppositely arranged on two sides of the moving contact, bosses are respectively arranged on the two side walls, a contact cavity for accommodating the moving contact is enclosed between the two bosses, guide surfaces are respectively arranged on one sides, close to the moving contact, of the two bosses, and the distance between the two guide surfaces is gradually increased along the direction close to the arc extinguishing chamber.

Preferably, a conductive plate is arranged on one side, far away from the fixed contact, of the rotating shaft system, an arc striking plate is arranged between the conductive plate and the arc extinguishing chamber, and the arc striking plate is connected with the conductive plate through a conductive piece.

According to the circuit breaker, the arc generated by the fixed contact and the moving contact can be extinguished in a thresh way through the arc extinguishing chamber, so that the circuit breaker is prevented from being damaged by the arc, and the breaking capacity of the circuit breaker is effectively improved.

Drawings

Fig. 1 is a schematic view of the assembly of an arc extinguishing chamber and a cell case according to the present utility model;

FIG. 2 is a cross-sectional view of the utility model creating FIG. 1;

fig. 3 is a schematic illustration of the overall structure of the arc extinguishing chamber in the first embodiment;

fig. 4 is a schematic illustration II of the overall structure of the arc extinguishing chamber in the first embodiment;

fig. 5 is a schematic view of the structure of the arc extinguishing chamber in the first embodiment when the contacts start to repel;

figure 6 is a schematic view of the arc chute in the first embodiment

Fig. 7 is a schematic view of the structure of the arc extinguishing chamber in the first embodiment when the contacts are completely separated;

fig. 8 is a schematic structural view of further optimization of the arc striking plate in the auxiliary arc extinguishing chamber in the first embodiment;

fig. 9 is a schematic illustration of the overall structure of the arc extinguishing chamber in the second embodiment;

fig. 10 is a schematic illustration II of the overall structure of the arc extinguishing chamber in the second embodiment;

fig. 11 is a schematic structural view of the arc extinguishing chamber in the second embodiment when the contacts start to repel;

fig. 12 is a schematic view of an arc extinguishing chamber in the second embodiment

Fig. 13 is a schematic structural view of the arc extinguishing chamber in the second embodiment when the contacts are completely separated;

fig. 14 is a schematic structural view of further optimization of the arc striking plate in the auxiliary arc extinguishing chamber of the second embodiment.

Detailed Description

The following examples are given in connection with the accompanying drawings to further illustrate embodiments of the arc chute of the utility model. The arc extinguishing chamber of the present utility model is not limited to the description of the embodiments below.

As shown in fig. 3, the arc extinguishing chamber of the present utility model includes two arc extinguishing components disposed oppositely, and an arc striking member 50 disposed between the two arc extinguishing components, the arc striking member 50 includes two arc striking structures respectively mated with the two arc extinguishing components, the two arc striking structures include an upper arc striking portion 61 and a lower arc striking portion 62, the upper arc striking portion 61 of the two arc striking structures is disposed between the two arc extinguishing components, and the upper arc striking portions 61 of the two arc striking structures are connected, the lower arc striking portion 62 of the two arc striking structures extends to one side of the corresponding arc extinguishing component, respectively, wherein at least one of the arc striking structures includes a stretching portion connected between the upper arc striking portion 61 and the lower arc striking portion 62, the stretching portion includes at least two oppositely disposed stretching pieces 63, and a connecting piece 64 connected between the at least two stretching pieces 63, and a stretching space 65 is defined between the connecting piece 64 and the two connected stretching pieces 63.

According to the arc extinguishing chamber, the stretching part is additionally arranged on the arc striking structure between the two arc extinguishing components, and the U-shaped stretching space 65 is formed by the connecting sheet 64 on the stretching part and the at least two stretching sheets 63, so that the smooth air flow at the inlet of the arc extinguishing chamber 94 can be ensured, the moving distance of the arc and the contact area of the arc and the arc striking piece 50 can be increased, the arc needs to enter the stretching space 65 and move along the stretching sheets 63 and the connecting sheet 64, the arc in the two arc extinguishing components is further prolonged, and the arc extinguishing capability of the whole arc extinguishing chamber is effectively improved.

The breaking performance of the circuit breaker is improved by improving the arc voltage of the arc extinguishing chamber in the short circuit breaking process, the breaking performance of the circuit breaker is improved in a plurality of methods for improving the arc voltage, the number of the grid plates and the distance are not guaranteed according to a direct current arc static volt-ampere characteristic theoretical formula uh=n0+EL, the theoretical arc voltage Uh can be often improved by increasing the number n of the grid plates or increasing the arc length L, but in practice, factors influencing the arc voltage have a plurality of factors, such as breaking speed, opening distance, final pressure, the number of the grid plates, grid plate distance, grid plate thickness, grid plate surface area, grid plate volume, grid plate notch shape, air field, magnetic field, electric field and the like, under the condition that the volume of the arc extinguishing chamber is unchanged, the number of the grid plates is increased, the thickness and the distance of the grid plates are not guaranteed, and if the grid plates are shorted or the grid plates are not fully utilized in the breaking process, the effect of cutting the arc is not achieved, so that ideal results are often not obtained when other parameters are unchanged. Otherwise, by increasing the number of the grid sheets, the thickness, the distance, the surface area and other parameters, the volume of the arc extinguishing chamber cannot be ensured. Secondly, the arc voltage is improved most obviously by increasing the arc length L, but the high voltage breaking is satisfied, and the arc extinguishing chamber is not obviously increased in the traditional arc extinguishing chamber. High voltage breaking can also be achieved by increasing the number of breaking points, but multipole synchronicity and product volume limitations are noted in the design. With the application of magnetic blowing and air blowing technology, on one hand, the electric arc is accelerated to enter the arc-extinguishing chamber, loop current limiting is performed rapidly, on the other hand, the effect of cooling and elongating the electric arc is achieved, the electric conductivity of the electric arc is reduced, the utilization rate of the grid sheet of the arc-extinguishing chamber is improved, and the arc-extinguishing effect of the circuit breaker is improved.

Therefore, the utility model can not only meet the volume of the arc-extinguishing chamber in the 250A shell frame, but also improve the arc-extinguishing performance of the two-pole DC1500V arc-extinguishing chamber by elongating the arc length.

As shown in fig. 1, the utility model also provides an embodiment of a circuit breaker, and the circuit breaker adopting the embodiment of the utility model comprises a shell 106, a fixed contact 111, a moving contact 41, a rotating shaft system 93, a release (not shown in the figure) and the arc extinguishing chamber 94 which are respectively arranged in the shell 106, wherein the fixed contact 111, the moving contact 41, the rotating shaft system 93 and the release are all positioned above the arc extinguishing chamber 94, the fixed contact 111 and the release are oppositely arranged at two sides of the rotating shaft system 93, the rotating shaft system 93 is positioned above the arc extinguishing chamber 94, the moving contact 41 is positioned between the rotating shaft system 93 and the arc extinguishing chamber 94, and the rotating shaft system 93 can drive the moving contact 41 to swing left and right so as to realize the contact and separation of the moving contact 41 and the fixed contact 111.

The circuit breaker provided by the utility model can rapidly extinguish the arc generated by the fixed contact 111 and the moving contact 41 through the arc extinguishing chamber, so that the circuit breaker is prevented from being damaged by the arc, and the breaking capacity of the circuit breaker is effectively improved.

As shown in fig. 3, the two arc extinguishing assemblies are a first arc extinguishing assembly 94-1 and a second arc extinguishing assembly 94-2, the first arc extinguishing assembly 94-1 and the second arc extinguishing assembly 94-2 respectively include a plurality of arc extinguishing grid sheets 940, the arc striking pieces 50, the first arc extinguishing assembly 94-1 and the second arc extinguishing assembly 94-2 are all installed on the side plates 51 and are respectively located at two ends of the side plates 51, the inlets of the two arc extinguishing assemblies are oppositely arranged, the arc striking pieces 50 are arranged between the two arc extinguishing assemblies, the first arc extinguishing assembly 94-1 is a main arc extinguishing assembly, the second arc extinguishing assembly 94-2 is an auxiliary arc extinguishing assembly, the two-section arc extinguishing assemblies are connected in series through the arc striking pieces 50, and the arc striking pieces 50 play roles of connection, arc striking, arc running and magnetic conduction.

Preferably, the thickness of the arc extinguishing bars 940 of this embodiment is 2mm, the interval is 2mm, the length of the arc extinguishing bars 940 is 45mm, and the number of the arc extinguishing bars 940 is 15×2. Can make full use of 250A shell and frame circuit breaker length and direction of height's size, the explosion chamber 94 that this time provides compares in current 250A circuit breaker explosion chamber 94, has increased the quantity, length and the surface area of bars piece, helps further to lengthen and cool off the electric arc, prevents that the temperature from being too high and burn-through or have great particle to block up, leads to the possibility that the bars piece takes place the short circuit, has promoted the heat capacity of explosion chamber 94. Of course, the thickness and spacing of the corresponding arc chute sheets 940 may be adjusted according to arc voltage requirements.

As shown in fig. 1, an inlet corresponding to the moving contact 41 is arranged above the middle of the arc extinguishing chamber 94, that is, an inlet is arranged above the arc striking member 50 between two arc extinguishing components, outlets respectively matched with the two arc extinguishing components are arranged at two ends of the arc extinguishing chamber 94, a first arc isolating grid 54 and a second arc isolating grid 55 are respectively arranged at the outlets, the first arc isolating grid 54 and the second arc isolating grid 55 are respectively arranged on the shell 106, and the phenomena of short circuit and fire disaster caused by the injection of larger charged particles to surrounding electrical equipment can be effectively prevented in the breaking process, so that a certain dissociation elimination effect is achieved;

the arc extinguishing chamber 94 is provided with two arc striking plates matched with two groups of arc extinguishing assemblies respectively, the two arc extinguishing plates are a first arc striking plate 52 and a second arc striking plate 53 matched with the first arc extinguishing assembly 94-1 and the second arc extinguishing assembly 94-2 respectively, one ends of the first arc striking plate 52 and the second arc striking plate 53 are matched with the fixed contact 111 and the movable contact 41 respectively, the other ends of the first arc striking plate 52 and the second arc striking plate 53 extend to the outlets of the first arc extinguishing assembly 94-1 and the second arc extinguishing assembly 94-2 respectively, one end of the first arc striking plate 52 is connected with the fixed contact 111, the first arc striking plate 52 is used for leading an arc on the fixed contact 111 into the first arc extinguishing assembly 94-1 rapidly, one ends of the second arc striking plate 53 are contacted or very close to each other when the movable contact 41 swings to the breaking farthest position, and the second arc striking plate 53 is used for leading the arc extinguishing assembly 94-2 on the movable contact 41 rapidly. As shown in fig. 8, the second striking plate 53 is connected to the conductive plate 100 of the trip unit through a conductive member 01. When the breaker is not opened for breaking the current contact 41, the second arc striking plate 53 can be magnetized through the conductive element 01, so that after the current contact 41 is completely repelled, the electric arc on the current contact 41 is more rapidly transferred to the second arc striking plate 53, and the second arc striking plate 53 is connected with the main loop, so that the electric field intensity at the second arc extinguishing assembly 94-2 is higher, the magnetic field matched with the U-shaped magnetic blowing structure is stronger, the quick transfer of the electric arc is facilitated, and the erosion surface area of the arc extinguishing assembly of the second arc extinguishing assembly 94-2 by the electric arc is increased.

As shown in fig. 2, the housing 106 includes two side walls disposed on two sides of the moving contact 41, where the two side walls are respectively provided with a boss 107, a contact cavity 2 for accommodating the moving contact 41 is enclosed between the two bosses 107, the moving contact 41 swings in the contact cavity 2, one side of the two bosses 107, which is close to the moving contact 41, is respectively provided with a guide surface 108, the distance between the two guide surfaces 108 gradually increases along the direction close to the arc extinguishing chamber 94, so that the cross-sectional area of the contact cavity 2, which is close to one end of the arc extinguishing chamber 94, is larger than the cross-sectional area of the contact cavity 2, which is far away from one end of the arc extinguishing chamber 94, and when gas is generated in the contact cavity 2, the gas pressure in the contact cavity 2 can be increased, the electric arc is driven to enter the arc extinguishing chamber 94, and the arc extinguishing speed is improved.

Further, three U-shaped magnetic blowing structures (not shown in the figure) are respectively arranged at the position between the moving contact 41 and the fixed contact 111 and the left and right arc extinguishing chambers 94, so that not only is the electrodynamic force of the moving contact 41 improved, but also the magnetic field intensity at the arranged position is increased, the transfer speed of the electric arc from the generation to the entering of the arc extinguishing chambers 94 and finally leaving of the arc extinguishing chambers 94 is further accelerated, and the arcing time is shortened.

As shown in fig. 3, the stretching part of the utility model comprises a plurality of stretching sheets 63, wherein the stretching sheets 63 form a stretching space 65 and a cooling space 67 which are alternately arranged through the connecting sheet 64, and the opening direction of the cooling space 67 is opposite to that of the stretching space 65.

As shown in fig. 3-8, in an embodiment one of the arc striking structures, the two arc striking structures of this embodiment respectively include an upper arc striking portion 61 and a lower arc striking portion 62, the upper arc striking portions 61 of the two arc striking structures are disposed between two arc extinguishing components, and the upper arc striking portions 61 of the two arc striking structures are connected, and the two upper arc striking portions 61 respectively face each other and extend obliquely upward to form a protruding portion (arc striking tip 66), and the lower arc striking portions 62 of the two arc striking structures are far away from each other to extend to the lower sides of the corresponding arc extinguishing components. The two striking structures of the striking piece 50 of this embodiment are all provided with the tensile portion, and the tensile portion is located between the corresponding upper striking portion 61 and lower striking portion 62, the tensile portion includes a plurality of tensile pieces 63, and a plurality of tensile pieces 63 set up with the arc extinguishing bars piece 940 parallel arrangement of arc extinguishing component respectively, the connection piece 64 includes preceding connection piece 641 and back connection piece 642, back connection piece 642 is used for connecting between the one end that adjacent tensile piece 63 kept away from corresponding arc extinguishing component to enclose into tensile space 65, preceding connection piece 641 is used for connecting between the one end that adjacent tensile piece 63 is close to corresponding arc extinguishing component to enclose into cooling space 67, tensile space 65 and cooling space 67 set up in turn, the opening direction of cooling space 67 sets up with tensile space 65 in opposite directions.

After passing through one stretching space 65, the electric arc can pass through the front connecting sheet 641 surrounding the adjacent cooling space 67 and move to the next stretching space 65, namely, the cooling space 67 can also play a role of connecting the stretching spaces 65 on two sides in series, and the arc extinguishing effect can be further improved through the stretching spaces 65 and the cooling spaces 67 which are alternately arranged.

The arc striking member 50 is designed to connect the two arc extinguishing chambers 94 first, so that the utilization rate of the bottom arc extinguishing grid plates of the two groups of arc extinguishing assemblies is improved; secondly, the arc running and the arc drawing function are performed, the arc is further cooled to improve the arc voltage, and the conductivity of the arc is reduced; finally, the middle bulge part of the arc striking structure plays an arc striking role, which is beneficial for the electric arc to enter the left and right arc extinguishing chambers 94 and rapidly limit the current of the circuit.

It will be appreciated that when only two tension sheets 63 are provided, only one rear connecting sheet 642 and two tension sheets 63 are required to enclose one tension space 65, and meanwhile, the cooling space 67 is not required to be provided, the number of tension sheets 63 can be adjusted according to the sizes of the arc extinguishing chamber 94 and the circuit breaker, preferably, the tension portion includes at least four tension sheets 63 to form a plurality of tension spaces 65 and a plurality of cooling spaces 67, and in this embodiment, nine tension sheets 63, four tension spaces 65 and four cooling spaces 67.

Further, the arc striking member 50 is integrally bent, and the connecting piece 64 is in a cambered surface shape, so that the processing difficulty and cost can be reduced, and the strength of the arc striking member 50 and the arc striking effect can be improved.

Further, the upper arc striking part 61 of the arc striking structure is obliquely arranged, the distance from the upper arc striking part 61 to the lower arc striking part 62 gradually increases along the direction away from the corresponding arc extinguishing assembly, and an arc striking tip 66 is formed at the connecting position of the upper arc striking parts 61 of the two arc striking structures.

Further, as shown in fig. 5-6, the distance from the lower arc striking portion 62 to the corresponding arc extinguishing assembly is a, the minimum distance from the stretching portion to the corresponding arc extinguishing assembly is d, and both a and d are larger than the minimum distance c from the moving contact 41 to the arc striking structure, so that when an arc enters the arc extinguishing chamber 94, the arc extinguishing gate sheet 940 at the bottom of the arc extinguishing assembly in the arc extinguishing chamber 94 can be prevented from being short-circuited;

in addition, still include with two arc extinguishing subassembly respectively complex two striking boards, the minimum distance on two striking boards to striking structure is b, b is greater than a, just b is greater than d, can prevent to pull open the back with the arc extinguishing subassembly short circuit of explosion chamber 94 of electric arc.

As shown in fig. 9-14, in a second embodiment of the arc striking structure, the two arc striking structures of the arc striking member 50 of this embodiment are both provided with the stretching portion, the stretching portion includes a plurality of stretching pieces 63, and the plurality of stretching pieces 63 are respectively disposed perpendicular to the arc extinguishing grid pieces 940 of the arc extinguishing assembly, the connecting piece 64 includes a lower connecting piece 643 and an upper connecting piece 644, the upper connecting piece 644 is used for connecting adjacent stretching pieces 63 and enclosing a stretching space 65 with an opening facing the lower arc striking portion 62, the lower connecting piece 643 is used for connecting adjacent stretching pieces 63 of the stretching space 65 and enclosing a cooling space 67 with an opening facing the upper arc striking portion 61, and the stretching space 65 and the cooling space 67 are alternately disposed. Of course, the stretching plate 63 may be disposed at an oblique angle with respect to the arc extinguishing grid 940, which falls within the protection scope of the present utility model.

The operation of the arc chute 94 will be described in detail with reference to fig. 5 and 6.

As shown in fig. 5, a schematic structural diagram of the arc extinguishing chamber 94 created by the present utility model is that contacts begin to repel each other, when the circuit breaker breaks current, the moving contact 41 begins to repel each other under the action of electric repulsion force, an arc starts to be generated between the moving contact and the fixed contact, and the arc root is transferred into the first arc extinguishing assembly 94-1 under the action of the air current and the first striking plate 52, because the moving contact 41 is relatively close to the arc extinguishing grid sheet 940 at the upper end of the first arc extinguishing assembly 94-1, the arc of the first arc extinguishing assembly 94-1 mainly moves between the arc extinguishing grid sheet 940 at the upper end of the arc extinguishing assembly and the moving contact 41.

As shown in fig. 6, the arc extinguishing chamber 94 is created in the structure of the utility model, when the moving contact 41 is separated to the middle area of the arc striking member 50, the electric gap c between the moving contact 41 and the arc striking tip 66 is gradually reduced, when the electric gap c is smaller than the electric gap a, the moving contact 41 discharges the arc striking member 50, so that the moving contact 41 is magnetized to reach a magnetic saturation state rapidly, and at the moment, the arc striking member 50 and the moving contact 41 are equipotential, so that a stronger electric field is generated between the arc striking member 50 and the first arc striking plate 52, under the action of air current and magnetic field, the arc at the first arc extinguishing assembly 94-1 is driven to continuously enter the grid at the lower end of the arc extinguishing assembly along the inclined plane of the arc striking member 50 until the arc extinguishing assembly of the first arc extinguishing assembly 94-1 is completely eroded by the arc under the action of magnetic blowing and air current.

As shown in fig. 7, which is a schematic diagram of a structure of the arc extinguishing chamber 94 with the fully-opened contacts, when the moving contact 41 is continuously opened from the intermediate position, the electric gap c between the moving contact 41 and the arc striking tip 66 is gradually increased, the electric arc of the second arc extinguishing assembly 94-2 mainly moves between the moving contact 41 and the arc striking member 50 because the first arc extinguishing assembly 94-1 is already connected with the electric arc, when the moving contact 41 continuously rotates to the opening position, the electric arc at the moving contact 41 is transferred to the second arc striking plate 53, and because the second arc extinguishing assembly 94-2 is connected with the first arc extinguishing assembly 94-1 in series through the arc striking member 50, the arc striking member 50 is already provided with an electric potential, a strong electric field still exists between the arc striking member 50 and the second arc striking plate 53, and under the action of air current and magnetic blowing, the electric arc at the second arc extinguishing assembly 94-2 is driven to enter the arc extinguishing assembly to cut and extinguish, and the circuit is rapidly limited under the combined action of the two-stage arc extinguishing chamber 94.

It should be noted that, in the description of the present utility model, the terms "upper," "lower," "left," "right," "inner," "outer," and the like refer to the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship conventionally put in use, merely for convenience of description, and do not refer to the fact that the apparatus or element referred to must have a specific orientation, and therefore should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating relative importance.

The foregoing is a further detailed description of the utility model in connection with the preferred embodiments, and it is not intended that the utility model be limited to the specific embodiments disclosed herein. It should be understood that those skilled in the art to which the present utility model pertains may make several simple deductions or substitutions without departing from the inventive concept, and should be considered as falling within the scope of the present utility model.

Claims (12)

1. An arc extinguishing chamber, including two arc extinguishing subassembly that set up relatively to and set up arc striking spare (50) between two arc extinguishing subassembly, its characterized in that: the arc striking piece (50) comprises two arc striking structures matched with the two arc extinguishing components respectively, the two arc striking structures respectively comprise an upper arc striking part (61) and a lower arc striking part (62), the upper arc striking part (61) of the two arc striking structures is arranged between the two arc extinguishing components, the upper arc striking parts (61) of the two arc striking structures are connected, the lower arc striking part (62) of the two arc striking structures respectively extends to one side of the corresponding arc extinguishing component, at least one of the two arc striking structures comprises a stretching part connected between the upper arc striking part (61) and the lower arc striking part (62), the stretching part comprises at least two stretching sheets (63) which are oppositely arranged, and a connecting sheet (64) connected between the at least two stretching sheets (63), and a stretching space (65) is defined between the connecting sheet (64) and the two connected stretching sheets (63).

2. The arc chute of claim 1 wherein: the stretching part comprises a plurality of stretching sheets (63), the stretching sheets (63) form stretching spaces (65) and cooling spaces (67) which are alternately arranged through the connecting sheets (64), and the opening direction of the cooling spaces (67) is opposite to that of the stretching spaces (65).

3. The arc chute of claim 1 wherein: the plurality of stretching sheets (63) are respectively arranged in parallel with the arc extinguishing grid sheets (940) of the arc extinguishing assembly, the connecting sheets (64) comprise front connecting sheets (641) and rear connecting sheets (642), the rear connecting sheets (642) are used for connecting adjacent stretching sheets (63) and enclosing the stretching space (65), and the front connecting sheets (641) are used for connecting the stretching sheets (63) adjacent to the stretching space (65) and enclosing the cooling space (67).

4. The arc chute of claim 1 wherein: the plurality of stretching sheets (63) are respectively perpendicular to arc extinguishing grid sheets (940) of the arc extinguishing assembly, the connecting sheets (64) comprise lower connecting sheets (643) and upper connecting sheets (644), the upper connecting sheets (644) are used for connecting adjacent stretching sheets (63) and enclosing into stretching spaces (65) with openings facing the lower arc striking parts (62), and the lower connecting sheets (643) are used for connecting adjacent stretching sheets (63) of the stretching spaces (65) and enclosing into cooling spaces (67) with openings facing the upper arc striking parts (61).

5. The arc chute of claim 1 wherein: the arc striking piece (50) is integrally bent, and the connecting piece (64) is in a cambered surface shape; the two arc striking structures of the arc striking piece (50) are provided with the stretching parts.

6. The arc chute of claim 1 wherein: the distance from the upper arc striking part (61) to the lower arc striking part (62) of the two arc striking structures gradually increases along the direction away from the corresponding arc extinguishing assembly, and an arc striking tip (66) is formed at the connecting position of the upper arc striking parts (61) of the two arc striking structures.

7. The arc chute of claim 6 wherein: the distance from the lower arc striking part (62) to the corresponding arc extinguishing assembly is a, the minimum distance from the stretching part to the corresponding arc extinguishing assembly is d, and the a and the d are both larger than the minimum distance c from the moving contact (41) to the arc striking structure; the arc extinguishing device is characterized by further comprising two arc striking plates which are respectively matched with the two arc extinguishing assemblies, wherein the minimum distance from the two arc striking plates to the arc striking structure is b, b is greater than a, and b is greater than d.

8. The arc chute of claim 1 wherein: an inlet is formed in the upper portion of the middle of the arc extinguishing chamber (94), namely, an inlet is formed in the upper portion of an arc striking piece (50) between two arc extinguishing components, outlets matched with the two arc extinguishing components are formed in the two ends of the arc extinguishing chamber (94), and a first arc isolating grid (54) and a second arc isolating grid (55) are arranged at the outlets.

9. The arc chute as in claim 3 or 4 wherein: the stretching portion includes at least four stretching sheets (63) forming a plurality of stretching spaces (65) and a plurality of cooling spaces (67).

10. A circuit breaker, characterized in that: the device comprises a fixed contact (111), a movable contact (41), a rotating shaft system (93) and the arc extinguishing chamber (94) as claimed in any one of claims 1 to 9, wherein the rotating shaft system (93) is positioned above the arc extinguishing chamber (94), the movable contact (41) is positioned between the rotating shaft system (93) and the arc extinguishing chamber (94), and the rotating shaft system (93) can drive the movable contact (41) to be in contact with the fixed contact (111).

11. The circuit breaker according to claim 10, characterized in that: still include casing (106), casing (106) are including setting up two lateral walls in moving contact (41) both sides relatively, be equipped with boss (107) on two lateral walls respectively, enclose into between two boss (107) and be used for holding contact cavity (2) of moving contact (41), one side that two boss (107) are close to moving contact (41) is equipped with guide surface (108) respectively, the distance between two guide surfaces (108) increases gradually along the direction that is close to explosion chamber (94).

12. The circuit breaker according to claim 10, characterized in that: one side of the rotating shaft system (93) far away from the fixed contact (111) is provided with a conductive plate (100), an arc striking plate is arranged between the conductive plate (100) and the arc extinguishing chamber (94), and the arc striking plate is connected with the conductive plate (100) through a conductive piece (01).