CN202917418U - Air-sweeping type low voltage arc extinguishing device and breaker - Google Patents
Air-sweeping type low voltage arc extinguishing device and breaker Download PDFInfo
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- CN202917418U CN202917418U CN 201220571209 CN201220571209U CN202917418U CN 202917418 U CN202917418 U CN 202917418U CN 201220571209 CN201220571209 CN 201220571209 CN 201220571209 U CN201220571209 U CN 201220571209U CN 202917418 U CN202917418 U CN 202917418U
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- arc
- arc extinguishing
- control device
- extinguishing grid
- air
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Abstract
The present utility model provides an air-sweeping type low voltage arc extinguishing device and a breaker. The arc extinguishing device comprises an explosion chamber; an arc extinguishing grid sheet group arranged inside the explosion chamber, the arc extinguishing grid sheet group is formed by stacking a plurality of arc extinguishing grid sheets; each arc extinguishing grid sheet is provided with a basal part and a first leg part and a second leg part extended from the basal part in the same direction, thus the arc extinguishing grid sheet group is provided with a first leg part group formed by the first leg parts of the arc extinguishing grid sheets and a second leg part group formed by the second leg parts of the arc extinguishing grid sheets, a gap between the first leg part group and the second leg part group is a first flowing path of arc and airflow, and the path is provided with a Laval nozzle structure characteristic. The breaker comprises the above arc extinguishing device. The arc extinguishing device has good air-sweeping arc extinguishing effects, and the breaker has good breaking capability.
Description
Technical field
The utility model relates to for the arc-control device of circuit breaker and has the circuit breaker of arc-control device.
Background technology
Arc-control device is the core component of circuit breaker, and its performance has directly determined the connecting-disconnecting function of circuit breaker.Low-voltage circuit breaker adopts grating arc-extinguishing chamber usually, and relies on the magnetic blow-out power driving electric arc that acts on the electric arc to enter the grid sheet, thus medium recovery strength behind cooling electric arc, raising arc voltage and the arc.
On the one hand, exist so that the demand of circuit breaker and the continuous miniaturization of arc-control device thereof, on the other hand, do not wish this miniaturization and cause breaking capacity of breaker to reduce, therefore, the design of arc-control device has been proposed challenge.
The product of existing design improves magnetic blow-out power by the optimal design of contact galvanic circle and arc chute chip architecture usually, and then improves connecting-disconnecting function.Yet, although the designer has paid very large effort in this respect, do not obtain gratifying result, in other words, so still there is improved space in the product of design aspect the connecting-disconnecting function raising.
Therefore, have a kind of demand, a kind of arc-control device for circuit breaker namely is provided, it has good arc quenching effect, thereby so that circuit breaker has good connecting-disconnecting function.Correspondingly, expectation provides a kind of circuit breaker with arc-control device like this.
The utility model content
According to above-mentioned shortcoming and defect, the purpose of this utility model is to solve at least some or all of the above-mentioned problems in the prior art.
According to a preferred embodiment of the present utility model, a kind of arc-control device for circuit breaker is provided, comprising: arc control device; And the arc extinguishing grid pieces group that is arranged in arc control device, this arc extinguishing grid pieces group forms by a plurality of arc extinguishing grid pieces are stacking; Wherein, the first shank and the second shank that each arc extinguishing grid pieces has a base portion and extends at equidirectional from this base portion, thus, the second shank group that the arc extinguishing grid pieces group has the first shank group that the first shank by each arc extinguishing grid pieces forms and is comprised of the second shank of each arc extinguishing grid pieces, gap between this first shank group and the second shank group forms the first flow path of electric arc and air-flow, and this first flow path has Laval spout structure feature.The Laval spout, it is also referred to as De Laval nozzle sometimes, itself be known in the prior art, the Laval spout has the roughly internal face of arc, has the entrance of convergent, the narrowest throat, the outlet section of flaring, air-flow constantly accelerates to throat at the entrance of convergent, reach velocity of sound in throat place air velocity, i.e. mach one is in outlet section, air velocity can further increase, and realizes Supersonic Flow.In the utility model, owing to adopting the Laval orifice design, therefore wherein air-flow can be realized Supersonic Flow, can improve thus the gas blast arc-quenching effect of the electric arc that produces when air-flow separates dynamic/static contact in the spout.
In above preferred embodiment of the present utility model, further preferably, has the gap between the neighboring of arc extinguishing grid pieces group and the inner rim of arc control device between the two, to form the air current flow path.Thus, can in this gap, form air-flow circulation, namely, can flow through from Laval spout exit a part of gas out and to be back to the porch of Laval spout by this gap, thereby improve the air pressure of porch, and then be conducive to further accelerate air current flow, realize better gas blast arc-quenching effect.
In above preferred embodiment of the present utility model, further preferably, at least a portion of the inner rim of arc control device has arcuate structure.Thus, owing to adopting arcuate structure, therefore can realize the fairshaped guiding to air-flow, thereby so that the shape of arc control device inner rim reduces as far as possible to the resistance of air-flow, and then be conducive to air-flow and turn back to easily, rapidly Laval spout porch to increase air pressure there, and then be conducive to further accelerate air current flow, realize better gas blast arc-quenching effect.
In above preferred embodiment of the present utility model, further preferably, be provided with air-flow reflection and guide plate on the inner rim of arc control device, have the gap between the neighboring of this air-flow reflection and guide plate and arc extinguishing grid pieces group between the two, to form the air current flow path.As described above, thus this gap can realize airflow reflux and be conducive to realize better gas blast arc-quenching effect.
In above preferred embodiment of the present utility model, further preferably, at least a portion of air-flow reflection and guide plate has arcuate structure.As described above, this arcuate structure is conducive to realize better gas blast arc-quenching effect.Being designed to have arcuate structure with direct inner rim with arc control device compares, the air-flow reflection and the guide plate that attach arcuate structure at the inner rim of arc control device can be so that the manufacturing of arc control device itself be more easy, namely, arc control device itself can design according to actual needs, and the reflection of air-flow and guiding realize by means of the air-flow reflection and the guide plate that attach suitable shape thereon, can improve the flexible design degree thus.
In above preferred embodiment of the present utility model, further preferably, attach on the side of formation first flow path of the first shank group and the second shank group and be provided with the insulation barrier identical with the shape of this side.Thus, therefore high-temperature electric arc directly ablate insulation barrier rather than the arc extinguishing grid pieces of directly ablating can reduce electric arc to the ablation of grid sheet.
In above preferred embodiment of the present utility model, further preferably, insulation barrier is formed by gas exhausted material.Thus, owing to insulation barrier is formed by gas exhausted material, therefore, when being ablated by high-temperature electric arc, can produce gas, be conducive to reduce arc temperature, improve the thermal conductivity of electric arc and improve air pressure in the Laval spout, and then be conducive to accelerate air-flow, and then realize better gas blast arc-quenching effect.
In above preferred embodiment of the present utility model, further preferably, be provided with the through hole that runs through as the gas outlet in the side in the face of the base portion of arc extinguishing grid pieces of arc control device.Thus, by means of the gas outlet, the gas in Laval spout exit can be derived, thereby be conducive to form pressure reduction and then accelerate air current flow, and then realize better gas blast arc-quenching effect.
According to a preferred embodiment of the present utility model, a kind of circuit breaker also is provided, this circuit breaker comprises the arc-control device according to above-mentioned arbitrary embodiment.Correspondingly, circuit breaker of the present utility model can have good gas blast arc-quenching effect, and then has good connecting-disconnecting function.
In above preferred embodiment of the present utility model, further preferably, this circuit breaker also comprises fixed contact and moving contact, fixed contact is arranged in the first flow path, this fixed contact is positioned at the upstream side of the stenosis of the first flow path for the air current flow direction in this first flow path.Thus, the moving contact that cooperates with fixed contact also correspondingly is arranged on the upstream of throat's (i.e. stenosis) of Laval spout, thus, when circuit breaker disconnects, the initial position of the electric arc that produces between the dynamic/static contact is positioned at the throat upstream, blow thereby can be accelerated by means of the Laval spout, can obtain thus good gas blast arc-quenching effect, and then have good connecting-disconnecting function.
Will be appreciated that, foregoing description only is for exemplary purpose, rather than will limit scope of the present utility model.
Description of drawings
Above-mentioned and the further feature of exemplary embodiment of the present utility model and advantage will become more obvious from following detailed description with the accompanying drawing, and that this description and accompanying drawing only are used for illustrative purpose rather than limit by any way scope of the present utility model, wherein:
Fig. 1 is the schematic three dimensional views that illustrates according to the arc-control device of a preferred embodiment of the present utility model.
Fig. 2 is the two-dimensional representation that illustrates according to the arc-control device of a preferred embodiment of the present utility model.
Fig. 3 is the schematic three dimensional views that illustrates according to the single arc extinguishing grid pieces of the arc-control device of a preferred embodiment of the present utility model.
Fig. 4 is the schematic three dimensional views that illustrates according to the arc control device of the arc-control device of a preferred embodiment of the present utility model;
Fig. 5 is the schematic three dimensional views that illustrates according to the insulation barrier of the arc-control device of a preferred embodiment of the present utility model.
Fig. 6 is the schematic diagram that illustrates according to half one of the Laval spout of the formation of the arc-control device of a preferred embodiment of the present utility model.
Fig. 7 is the schematic diagram that illustrates about the internal pressure of as shown in Figure 6 Laval spout.
Fig. 8 is the schematic diagram that illustrates about the internal gas flow speed of as shown in Figure 6 Laval spout.
Embodiment
Each exemplary embodiment of the present utility model is described below with reference to accompanying drawings.
About aforementioned and other technology contents, characteristics and effect of the present utility model,, can clearly present with reference to the accompanying drawings in the detailed description to embodiment in following cooperation.The direction term of mentioning in following examples such as: upper and lower, left and right, front or rear etc., only is direction with reference to the accompanying drawings.Therefore, the direction term of use is to illustrate not to be to limit the utility model, and in addition, in whole embodiment, identical drawing reference numeral represents identical element.
At first with reference to circuit breaker and the arc-control device thereof of Fig. 1 and 2 description according to a preferred embodiment of the present utility model, wherein Fig. 1 is the schematic three dimensional views that arc-control device is shown, and Fig. 2 is the two-dimensional representation that arc-control device is shown.As illustrated in fig. 1 and 2, comprise according to circuit breaker of the present utility model: arc control device 10; And the arc extinguishing grid pieces group 20 that is arranged in arc control device, this arc extinguishing grid pieces group 20 forms by a plurality of arc extinguishing grid pieces are stacking.
With reference to Fig. 3, it is the schematic three dimensional views of the single arc extinguishing grid pieces in the grid sheet group 20 that illustrates as shown in Figure 1 simultaneously.As shown in Figure 3, each arc extinguishing grid pieces has a base portion 201 and has gap 207 from this base portion 201 between the first shank 203 that equidirectional extends and the second shank 205, the first shanks 203 and the second shank 205.When a plurality of arc extinguishing grid pieces are stacked and form as shown in Figure 1 arc extinguishing grid pieces group, the second shank group that arc extinguishing grid pieces group 20 correspondingly has the first shank group that the first shank 203 by each arc extinguishing grid pieces forms, be comprised of the second shank 205 of each arc extinguishing grid pieces, the gap that is formed by the gap 207 of each arc extinguishing grid pieces.Gap between this first shank group and the second shank group forms the spout 50(of the first flow path that is used as electric arc and air-flow referring to Fig. 1 or 2), this spout has Laval spout structure feature.
As previously mentioned, the architectural feature of Laval spout itself is known, therefore, correspondingly, no longer the shape of spout 50 is given unnecessary details at this.Although the Laval spout itself is known, but the Laval spout is not applied in the prior art in the orifice design of arc extinguishing grid pieces of arc-control device of circuit breaker, and utility model people of the present utility model is through a large amount of theoretical researches and practice, proposed innovatively the Laval spout is applied in the arc-control device, this just the utility model to the contribution of prior art it
With reference to Fig. 2, also comprise fixed contact 70 and moving contact (not shown) according to circuit breaker of the present utility model, fixed contact 70 is arranged in the spout 50, this fixed contact 70 is positioned at the upstream side of the stenosis (so-called " throat ") of spout 50 for the air current flow direction (shown in dotted arrow) in this spout 50.Notice, because fixed contact is positioned at the upstream side of the stenosis of spout 50, when dynamic/static contact was closed, moving contact also was positioned at the upstream side of the stenosis of spout 50 naturally, that is, the position of the fixed contact shown in Fig. 2 70 can be understood as dynamic/static contact position when dynamic/static contact is closed.Like this, when dynamic/static contact separates, produce the electric arc of high temperature, this high-temperature electric arc heat intensive peripheral gas, thereby sharply form high gas pressure, because dynamic/static contact is positioned at the upstream side of the stenosis of spout 50, therefore the initial position of aforementioned high pressure also is positioned at the upstream side of the stenosis of spout 50, and this high pressure adds flow speed and direction spout rear portion, spout downstream and gas outlet by means of the Laval spout.Because it is increasing that the air-flow in the spout is from upstream to velocity of downstream, and realization Supersonic Flow (can further describe this below with reference to Fig. 8), therefore, the air-flow in the spout is very good to the gas blast arc-quenching effect of electric arc, is conducive to improve the connecting-disconnecting function of circuit breaker.
In order further to improve the gas blast arc-quenching effect, in the utility model, as illustrated in fig. 1 and 2, has gap 60 between the inner rim of the neighboring of arc extinguishing grid pieces group 20 and arc control device 10 between the two, to form the air current flow path.Because when electric arc flows towards Laval spout downstream, the gas pressure of voltage contact area can descend to some extent, like this, shown in the arrow of Fig. 2, can form from spout 50 upstream extremities (near the bottom of Fig. 2), to the throat of spout, to the backward channels of the downstream of spout, 60 formation to the gap, to the closed loop flow path of spout 50 upstream extremities, be conducive to thus improve the air pressure of spout 50 upstream extremities, realize better gas blast arc-quenching effect thereby further strengthen air-flow power.
Now combination is with reference to Fig. 4, and it is the schematic three dimensional views that the arc control device of arc-control device as shown in Figure 1 are shown.Thereby further improve the gas blast arc-quenching effect in order to improve airflow reflux speed, in the utility model, at least a portion of the inner rim of arc control device 10 has arcuate structure 101.In the circulation channel that gap 60 forms, certainly exist air-flow and change nyctitropic place, the place that air-flow is changed the direction place is designed to arcuate structure and can be conducive to reduce the air-flow changed course to the reduction impact of air velocity.Certainly, the shape of the inner rim of arc control device 10 also needs to consider some other factors, for example layout of other associated components.
Noticing, in the embodiment shown in Fig. 1,2 and 4, is directly the shape of the inner rim of arc control device to be designed to be conducive to the shape that air-flow accelerates, and namely at least a portion adopts arcuate structure.Alternatively, can adopt the replacement scheme of setting up air-flow reflection and guide plate at the inner rim of arc control device, this air-flow reflection and guide plate can adopt aforesaid part arc structural design, thereby are conducive to reduce the adverse effect to the circulation air velocity.
Now simultaneously with reference to Fig. 1,2 and 5, wherein Fig. 5 be illustrate as shown in Figure 1 the schematic three dimensional views of insulation barrier 30 of arc-control device.In order to reduce high-temperature electric arc to the ablation of arc extinguishing grid pieces, in the utility model, the side of the formation spout 50 of the first shank group and the second shank group (i.e. two inboards that the shank group faces with each other) upper attaching is provided with insulation barrier 30.The shape of this insulation barrier 30 is identical with the shape of aforementioned side, and thus, the gap between the insulation barrier 30 also meets the design feature of Laval spout, thereby is conducive to gas blast arc-quenching.In order further to improve the gas blast arc-quenching effect, insulation barrier 30 can be formed by gas exhausted material, and insulation barrier can produce gas under the ablation of high-temperature electric arc thus, thereby is conducive to improve air pressure, and then improves air velocity, and then is conducive to gas blast arc-quenching.
As shown in figs. 1 and 4, be provided with in the side in the face of the base portion of arc extinguishing grid pieces of arc control device and run through through hole 103 as the gas outlet.A part of gas of the downstream of spout 50 is discharged by through hole 103, flows towards downstream thereby be conducive to air-flow, and then is conducive to gas blast arc-quenching.
As illustrated in fig. 1 and 2, arc-control device of the present utility model can also comprise the fixture 40 that a plurality of arc extinguishing grid pieces are fixed together.Obviously, the setting of fixture 40 is not limited to the left and right sides that is positioned at arc extinguishing grid pieces shown in the figure, and it can also have other design, even can not have fixture, and by the fixing a plurality of grid sheets of other mode.
Describe the air-blowing situation in the Laval spout of arc-control device of the present utility model referring now to Fig. 6-8, wherein Fig. 6 is the schematic diagram that illustrates according to half one of the Laval spout of the formation of the arc-control device of a preferred embodiment of the present utility model; Fig. 7 is the schematic diagram that illustrates about the internal pressure of as shown in Figure 6 Laval spout; Fig. 8 is the schematic diagram that illustrates about the internal gas flow speed of as shown in Figure 6 Laval spout.In Fig. 6, show half shape of the Laval spout of arc-control device of the present utility model, represent each position in the spout by abscissa x and ordinate y.In Fig. 7, the abscissa shown in its abscissa corresponding diagram 6 namely represents each location point along the spout length direction; And ordinate represents air-flow air pressure that should each position.As can be seen from Figure 7, in the utility model, from the downstream of swimming over to of spout, pressure constantly reduces.In Fig. 8, the abscissa shown in its abscissa corresponding diagram 6 namely represents each location point along the spout length direction; And ordinate represents air velocity that should each position.As can be seen from Figure 8, from the downstream of swimming over to of spout, air velocity constantly increases, increase to mach one from 0.6 Mach, increase to again even surpass 2 Mach, thereby realized Supersonic Flow, therefore, in the utility model, can realize good gas blast arc-quenching effect.
Be generally low-voltage circuit breaker according to circuit breaker of the present utility model, include but not limited to, miniature circuit breaker, breaker of plastic casing and frame circuit breaker.
Although on the basis with reference to each embodiment, the utility model is described in specification and is illustrated in the accompanying drawings, but those skilled in the art will appreciate that above-described embodiment only is that preferred embodiment the utility model is not limited to this.Some technical characterictic among the embodiment may not be essential for solving specific technical problem, thereby can not have or omit these technical characterictics and the formation of non-influence technique solution of problem or technical scheme.In addition, the feature of an embodiment, key element and/or function can with the suitably mutually combination of feature, key element and/or the function of other one or more embodiment, in conjunction with or cooperates, unless this combination, combination or cooperation obviously can not be implemented.
Claims (7)
1. air blowing type low-voltage arc eliminating device comprises:
Arc control device; And
Be arranged in the arc extinguishing grid pieces group of arc control device, this arc extinguishing grid pieces group forms by a plurality of arc extinguishing grid pieces are stacking;
It is characterized in that,
The first shank and the second shank that each arc extinguishing grid pieces has a base portion and extends at equidirectional from this base portion, thus, the second shank group that the arc extinguishing grid pieces group has the first shank group that the first shank by each arc extinguishing grid pieces forms and is comprised of the second shank of each arc extinguishing grid pieces, gap between this first shank group and the second shank group forms the first flow path of electric arc and air-flow, and described the first flow path has Laval spout structure feature.
2. arc-control device as claimed in claim 1 is characterized in that, has the gap between the neighboring of described arc extinguishing grid pieces group and the inner rim of described arc control device to form the air current flow path between the two.
3. arc-control device as claimed in claim 1, it is characterized in that, be provided with air-flow reflection and guide plate on the inner rim of described arc control device, have the gap between the neighboring of this air-flow reflection and guide plate and described arc extinguishing grid pieces group between the two, to form the air current flow path.
4. arc-control device as claimed in claim 3 is characterized in that, at least a portion of described air-flow reflection and guide plate has arcuate structure.
5. such as the described arc-control device of one of claim 1-4, it is characterized in that, attach on the side of described the first shank group and described the first flow path of the formation of described the second shank group and be provided with the insulation barrier identical with the shape of this side.
6. a circuit breaker is characterized in that, this circuit breaker comprises the described arc-control device such as one of claim 1-5.
7. circuit breaker as claimed in claim 6, it is characterized in that, this circuit breaker also comprises fixed contact and moving contact, described fixed contact is arranged in described the first flow path, this fixed contact is positioned at the upstream side of the stenosis of described the first flow path for the air current flow direction in this first flow path.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220571209 CN202917418U (en) | 2012-11-01 | 2012-11-01 | Air-sweeping type low voltage arc extinguishing device and breaker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220571209 CN202917418U (en) | 2012-11-01 | 2012-11-01 | Air-sweeping type low voltage arc extinguishing device and breaker |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202917418U true CN202917418U (en) | 2013-05-01 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220571209 Expired - Lifetime CN202917418U (en) | 2012-11-01 | 2012-11-01 | Air-sweeping type low voltage arc extinguishing device and breaker |
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| Country | Link |
|---|---|
| CN (1) | CN202917418U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114420517A (en) * | 2022-03-31 | 2022-04-29 | 晟望电气有限公司 | Sulfur hexafluoride gas insulation switch |
-
2012
- 2012-11-01 CN CN 201220571209 patent/CN202917418U/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114420517A (en) * | 2022-03-31 | 2022-04-29 | 晟望电气有限公司 | Sulfur hexafluoride gas insulation switch |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20130501 |
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| CX01 | Expiry of patent term |