CN112447448A - Miniature non-sealing direct current contactor arc extinguishing structure - Google Patents
Miniature non-sealing direct current contactor arc extinguishing structure Download PDFInfo
- Publication number
- CN112447448A CN112447448A CN202011427415.9A CN202011427415A CN112447448A CN 112447448 A CN112447448 A CN 112447448A CN 202011427415 A CN202011427415 A CN 202011427415A CN 112447448 A CN112447448 A CN 112447448A
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- CN
- China
- Prior art keywords
- arc extinguishing
- arc
- contactor
- magnetic steel
- sealed
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H50/00—Details of electromagnetic relays
- H01H50/02—Bases; Casings; Covers
- H01H50/04—Mounting complete relay or separate parts of relay on a base or inside a case
- H01H50/041—Details concerning assembly of relays
- H01H50/045—Details particular to contactors
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/30—Means for extinguishing or preventing arc between current-carrying parts
- H01H9/34—Stationary parts for restricting or subdividing the arc, e.g. barrier plate
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/30—Means for extinguishing or preventing arc between current-carrying parts
- H01H9/44—Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet
- H01H9/443—Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet using permanent magnets
Abstract
The invention provides a miniature non-sealing direct current contactor arc extinguishing structure which comprises an arc extinguishing chamber, wherein two fixed contacts and two movable contacts are arranged in the arc extinguishing chamber, the fixed contacts and the movable contacts are opposite in position, two first magnetic steels are arranged outside the arc extinguishing chamber, the two first magnetic steels are arranged on a central connecting line of the two fixed contacts, two second magnetic steels are also arranged outside the arc extinguishing chamber, and the two second magnetic steels are respectively arranged on two sides of the central connecting line of the two fixed contacts; and an arc striking grid is also arranged in the arc extinguishing chamber and is arranged between the fixed contact and the first magnetic steel. The arc extinguishing structure enhances the arc extinguishing capability of the arc extinguishing chamber of the existing non-sealing contactor, improves the electrical service life level of the non-sealing contactor, is beneficial to reducing the volume of the arc extinguishing chamber, and is convenient for realizing the miniaturized design of the contactor.
Description
Technical Field
The invention belongs to the technical field of contactors, and particularly relates to an arc extinguishing structure of a miniaturized non-sealed direct current contactor.
Background
The arc extinguishing system is a key part in the contactor, when the contactor is connected and disconnected with high current, electric arcs can be generated between the movable contact and the fixed contact, the energy of the electric arcs is extremely high, if no measures are taken for arc extinguishing, the contact contacts and peripheral parts of the contact contacts can be seriously ablated, and the service life of the contactor is greatly reduced.
Therefore, arc extinguishing measures are taken in the design of the contactor, and the existing arc extinguishing technology is different among ceramic soldering sealing contactors, epoxy potting contactors and non-sealing contactors. In the ceramic soldering sealing contactor, generally, a ceramic arc extinguishing cavity is adopted, ceramics have a cooling arc extinguishing effect, the ceramic arc extinguishing cavity is made of ceramics, the ceramic arc extinguishing cavity can form an arc extinguishing chamber with better sealing performance by welding with a static contact and an actuating system, arc extinguishing gases such as hydrogen and nitrogen are filled inside the ceramic arc extinguishing cavity, meanwhile, second magnetic steel and first magnetic steel for enhancing a magnetic field are additionally arranged outside the cavity, electric arc is biased through the magnetic field, the ceramic arc extinguishing cavity is in contact with the ceramic arc extinguishing chamber, and the ceramic cooling arc extinguishing effect is utilized to play a better arc extinguishing effect. The structure is shown in fig. 1.
The arc extinguishing effect is better, but owing to adopted ceramic brazing seal structure, the technological process of brazing is complicated, for guaranteeing the leakproofness, reduces filling gas and reveals the risk, and is high to the requirement of brazing quality, and the technological process control requires highly, and the product percent of pass is difficult to guarantee.
The epoxy potting contactor changes the ceramic soldering sealing structure into a nylon arc extinguishing chamber epoxy glue pouring sealing structure, and reserves measures of filling arc extinguishing gas inside and second magnetic steel outside, as shown in figure 2. Although the ceramic brazing process link is omitted, the epoxy potting process also needs accurate process control to ensure the sealing performance of the arc extinguish chamber, and the qualification rate is difficult to ensure as same as ceramic brazing.
The non-sealed contactor does not adopt filling arc-extinguishing gas, so that complex ceramic soldering or epoxy potting procedures are not needed, the assembly process is greatly simplified, and the qualification rate is high. In order to achieve the arc extinguishing effect, the distance between the moving contact and the static contact is increased, the arc is difficult to maintain by lengthening the arc, and meanwhile, the magnetic steel arc blowing measure is adopted to realize arc blowing and arc extinguishing, as shown in figure 3.
The existing non-sealed contactor arc extinguish chamber is made of nylon materials, is convenient to form and has certain insulating and arc ablation resistance, but compared with ceramic materials, the existing non-sealed contactor arc extinguish chamber is poor in ablation resistance, so that the existing non-sealed contactor arc extinguish chamber is low in electric service life and difficult to achieve a good application effect. Meanwhile, in order to prevent over ablation of the arc extinguish chamber, the distance between the wall of the arc extinguish chamber and a movable contact and a fixed contact is large, so that the arc extinguish chamber is large in size and cannot be designed in a miniaturized mode.
Therefore, there is a need in the art to develop an arc extinguishing structure that can overcome the above-mentioned problems in the prior art.
Disclosure of Invention
The invention aims to provide an arc extinguishing structure of a miniaturized non-sealed direct current contactor, which can solve the technical problems of weak arc extinguishing capability, limited electric service life and strong arc extinguishing volume of the existing non-sealed contactor.
The invention provides a miniature non-sealing direct current contactor arc extinguishing structure which comprises an arc extinguishing chamber, wherein two static contacts and two moving contacts are arranged in the arc extinguishing chamber, the static contacts are opposite to the moving contacts, two first magnetic steels are arranged outside the arc extinguishing chamber and are arranged on a central connecting line of the two static contacts, two second magnetic steels are also arranged outside the arc extinguishing chamber and are respectively arranged on two sides of the central connecting line of the two static contacts;
and an arc striking grid is further arranged in the arc extinguishing chamber and arranged between the fixed contact and the first magnetic steel.
Preferably, the arc ignition grid is provided as a ceramic arc ignition grid.
Preferably, the edges of contact surfaces of the moving contact and the fixed contact are arranged to be round structures.
Preferably, the second magnetic steel is arranged into an enhanced magnetic steel arc blowing structure with an anti-reverse chamfer.
Preferably, the second magnetic steel is set to be arc-blowing magnetic steel.
Preferably, the two second magnetic steels are arranged on a perpendicular bisector of a connecting line of centers of the two fixed contacts.
Preferably, the first magnetic steel and the second magnetic steel are arranged in the same direction.
Preferably, an installation groove is formed in the arc extinguish chamber, and the first magnetic steel and the second magnetic steel are embedded in the installation groove.
Preferably, the fixed contact and the arc extinguish chamber are welded into an integrated structure or are formed into an integrated structure through injection molding.
Preferably, the first magnetic steel is arranged into a magnetic conductive sheet, and the magnetic conductive sheet is arranged into a U-shaped structure.
Compared with the prior art, the miniature non-sealing direct current contactor arc extinguishing structure has the following beneficial effects:
1. the ceramic arc striking grid design is adopted in the arc extinguishing chamber of the non-sealed contactor, so that the effect of quickly extinguishing the arc is achieved, the ablation effect of the arc on the contact is reduced, the ablation of the arc on the side wall of the nylon arc extinguishing chamber is also prevented, and the electric service life level of the contactor is improved.
2. According to the invention, the anti-reverse chamfer structure design is added to the second magnetic steel and the arc extinguish chamber second magnetic steel mounting groove, the effect of magnetic steel blind mounting is achieved, the product assembly efficiency is effectively improved, the fatal problem that the arc blowing effect disappears due to the reverse mounting of the magnetic steel polarity is reduced, and the product reliability is improved.
3. The arc extinguishing structure enhances the arc extinguishing capability of the arc extinguishing chamber of the existing non-sealing contactor, improves the electrical service life level of the non-sealing contactor, is beneficial to reducing the volume of the arc extinguishing chamber, and is convenient for realizing the miniaturized design of the contactor.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic structural diagram of an arc extinguish chamber structure of a ceramic soldering sealing contactor in the prior art;
FIG. 2 is a schematic structural diagram of an arc extinguishing chamber structure of an epoxy potting contactor in the prior art;
FIG. 3 is a schematic structural diagram of an arc extinguishing chamber structure of a non-sealed contactor in the prior art;
fig. 4 is a schematic structural diagram of an arc extinguishing structure of the miniaturized non-sealed direct current contactor of the invention;
fig. 5 is an exploded view of the arc extinguishing structure of the miniaturized non-sealed dc contactor according to the present invention;
fig. 6 is a partial structural schematic diagram of an arc extinguishing structure of the miniaturized non-sealed direct current contactor according to the present invention;
fig. 7 is a second partial structural schematic diagram of an arc extinguishing structure of the miniaturized non-sealed dc contactor according to the present invention;
fig. 8 is a schematic diagram of an arc extinguishing structure of the miniaturized non-sealed dc contactor according to the present invention;
FIG. 9 is a schematic view of the magnetic field blowing principle in the arc extinguishing chamber of the present invention;
fig. 10 is a schematic view of the principle of arc extinguishing by the arc striking grid in the arc extinguishing chamber of the present invention.
Description of reference numerals:
1. arc extinguish chamber 2, moving contact 21 and moving contact
3. Static contact 31, static contact 4 and first magnetic steel
5. Second magnetic steel 6, arc striking grid 7 and arc blowing magnetic field
8. Reverse chamfer
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.
FIG. 1 is a schematic structural diagram of an arc extinguish chamber structure of a ceramic soldering sealing contactor in the prior art; FIG. 2 is a schematic structural diagram of an arc extinguishing chamber structure of an epoxy potting contactor in the prior art; fig. 3 is a schematic structural diagram of an arc extinguishing chamber structure of a non-sealed contactor in the prior art.
As shown in fig. 4 to 7, the arc extinguishing structure of the miniaturized non-sealed dc contactor provided by the present invention includes an arc extinguishing chamber 1, wherein two fixed contacts 3 and two moving contacts 2 are disposed in the arc extinguishing chamber 1, the fixed contacts 3 are opposite to the moving contacts 2, two first magnetic steels 4 are further disposed in the arc extinguishing chamber 1, the two first magnetic steels 4 are disposed on a central connection line of the two fixed contacts 3, two second magnetic steels 5 are further disposed in the arc extinguishing chamber 1, and the two second magnetic steels 5 are respectively disposed on two sides of the central connection line of the two fixed contacts 3. Wherein, still be provided with striking bars 6 in the explosion chamber 1, striking bars 6 set up between static contact 3 and first magnet steel 4, correspondingly, are provided with striking bars recess in the explosion chamber 1, only need during the installation with striking bars 6 insert striking bars recess can realize fixed connection.
The static contact 3 and the shell of the arc extinguish chamber 1 are welded into an integrated structure or are injected into an integrated structure. When the arc extinguish chamber 1 is a ceramic arc extinguish chamber, the static contact 3 and the arc extinguish chamber 1 are arranged into an integrated structure in a welding mode; when the arc extinguish chamber 1 is a nylon arc extinguish chamber, the static contact 3 and the arc extinguish chamber 1 are arranged into an integrated structure in an injection molding mode.
In a further embodiment of the invention, the ignition grid 6 is provided as a ceramic ignition grid. The arc striking grid 6 is transversely arranged on the transverse direction of the central connecting line of the two fixed contacts 3.
In a further embodiment of the invention, as shown in fig. 5 and 7, the second magnetic steel 5 is provided with an enhanced magnetic steel arc blowing structure with an anti-reverse chamfer 8. Preferably, the second magnetic steel 5 is set as a blowing magnetic steel. Preferably, as shown in fig. 5, the first magnetic steel 4 is configured as a magnetic conductive sheet, and the magnetic conductive sheet is configured as a U-shaped structure.
The enhanced magnetic steel arc blowing structure is characterized in that two second magnetic steels 5 are communicated by adopting a magnetic conductive sheet (a first magnetic steel 4), the two second magnetic steels 5 are respectively adsorbed on two surfaces on the inner side of the magnetic conductive sheet, a magnetic line of force passes through the magnetic conductive sheet from one second magnetic steel 5 to flow to the other second magnetic steel 5 and penetrates out of the other second magnetic steel 5, the magnetic line of force passes through an air region in the middle of a movable contact and a fixed contact, the original second magnetic steel 5 is returned, the whole magnetic resistance is reduced, and the magnetic field between the two second magnetic steels 5 can be enhanced by the arrangement.
In order to facilitate the installation, an installation groove is arranged in the arc extinguish chamber 1, and the first magnetic steel 4 and the second magnetic steel 5 are embedded in the installation groove.
The invention adopts the design of the ceramic arc striking grid in the non-sealed contactor arc extinguishing chamber 1, and the arc striking grid 6 is made of ceramic material, thereby having the function of arc extinguishing. As shown in fig. 8 to 10, when the main circuit is disconnected, electric arcs can be generated between the upper and lower corresponding moving and static contacts 31, under the action of an arc-blowing magnetic field 7 formed by arc-blowing magnetic steel, the electric arcs can be pulled to two sides, and after the electric arcs contact ceramic arc-striking grids 6 on two sides, the electric arcs can be rapidly extinguished under the cooling action, so that the rapid arc-extinguishing effect is achieved, the ablation effect of the electric arcs on the contacts is reduced, meanwhile, the ablation of the electric arcs on the side wall of the nylon arc-extinguishing chamber 1 is also prevented, and the electric service life level of the contactor is improved.
In order to further increase the difficulty of arcing between the movable contact 21 and the fixed contact 31, the contact surface between the movable contact 21 and the fixed contact 31 is configured to be a rounded structure or a circular arc shape, as shown in fig. 5 and 6. The design of edge fillet structure has effectively reduced the marginal electric field distortion of sound contact 31, has increased the arcing degree of difficulty, has reduced the time of arcing, has reduced the electric arc to main circuit spare part (sound contact 3, contact) and the ablation of explosion chamber 1, with the combined action of striking grid 6, has improved non-sealing contactor's electric life level.
According to the invention, the structural design of the anti-reverse chamfer 8 is added to the second magnetic steel 5 and the mounting groove of the second magnetic steel 5 in the arc extinguish chamber 1, namely, the anti-reverse chamfer 8 is added at the upper right corner or the upper left corner of the second magnetic steel 5, so that no matter how the assembly is carried out, the polarity of the arc-blowing magnetic steel cannot be reversely assembled, the effect of magnetic steel blind assembly is achieved, the assembly efficiency of products is effectively improved, the fatal problem that the arc-blowing effect disappears caused by the reverse installation of the polarity of the magnetic steel is reduced, and the reliability of the products is improved.
The arc extinguishing structure enhances the arc extinguishing capability of the arc extinguishing chamber of the existing non-sealing contactor, improves the electrical service life level of the non-sealing contactor, is beneficial to reducing the volume of the arc extinguishing chamber 1, and is convenient for realizing the miniaturized design of the contactor.
Preferably, two second magnet steels 5 are arranged on the perpendicular bisector of the connecting line of the centers of the two fixed contacts 3, so that the magnetic induction intensity in the arc extinguish chamber 1 is more uniform, and the magnetic induction intensity can be further increased.
Preferably, the first magnetic steel 4 and the second magnetic steel 5 are arranged in the same direction. Specifically, two first magnet steels 4 are placed in the same direction (i.e. N, S poles of two magnet steels are opposite), and two second magnet steels 5 are placed in the same direction as the two first magnet steels 4.
On the basis of the existing non-sealed contactor, the ceramic arc striking grid 6 is added in the arc extinguishing chamber 1 of the contactor for arc extinguishing and arc extinguishing, the structure of the contact of the moving contact and the fixed contact 3 is improved, the edge of the contact surface is changed into a fillet structure, the distortion of the edge electric field is further reduced, the arc starting difficulty is increased, and meanwhile, the enhanced magnetic steel arc blowing structure with the anti-reverse chamfer 8 is adopted. The comprehensive effect of the three measures strengthens the arc extinguishing capability of the arc extinguishing chamber 1 of the existing non-sealing contactor, improves the electrical service life level of the non-sealing contactor, and is favorable for reducing the volume of the arc extinguishing chamber and convenient for realizing the miniaturized design of the contactor.
It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.
Claims (10)
1. An arc extinguishing structure of a miniaturized non-sealed direct current contactor is characterized by comprising an arc extinguishing chamber, wherein two fixed contacts and two moving contacts are arranged in the arc extinguishing chamber, the fixed contacts are opposite to the moving contacts, two first magnetic steels are arranged outside the arc extinguishing chamber and are arranged on a central connecting line of the two fixed contacts, two second magnetic steels are also arranged outside the arc extinguishing chamber and are respectively arranged on two sides of the central connecting line of the two fixed contacts;
and an arc striking grid is further arranged in the arc extinguishing chamber and arranged between the fixed contact and the first magnetic steel.
2. The miniaturized non-sealed DC contactor arc extinguishing structure according to claim 1, wherein the arc striking grid is provided as a ceramic arc striking grid.
3. The arc extinguishing structure of the miniaturized non-sealed DC contactor as claimed in claim 1, wherein the contact surface edge of the moving contact and the static contact is configured as a round angle structure.
4. The arc extinguishing structure of the miniaturized non-sealed direct current contactor according to claim 1, wherein the second magnetic steel is provided with an enhanced magnetic steel arc blowing structure with an anti-reverse chamfer.
5. The arc extinguishing structure of the miniaturized non-sealed DC contactor as claimed in claim 4, wherein the second magnetic steel is configured as an arc-blowing magnetic steel.
6. The arc extinguishing structure of the miniaturized non-sealed DC contactor as claimed in claim 1, wherein the two second magnetic steels are disposed on a perpendicular bisector of a connecting line of centers of the two stationary contacts.
7. The arc extinguishing structure of the miniaturized non-sealed DC contactor as claimed in claim 1, wherein the first magnetic steel and the second magnetic steel are arranged in the same direction.
8. The arc extinguishing structure of the miniaturized non-sealed direct current contactor according to claim 1, wherein an installation groove is formed in the arc extinguishing chamber, and the first magnetic steel and the second magnetic steel are embedded in the installation groove.
9. The miniaturized non-sealed DC contactor arc extinguishing structure according to claim 8, wherein the stationary contact and the arc extinguishing chamber are welded into an integrated structure or are injection molded into an integrated structure.
10. The arc extinguishing structure of the miniaturized non-sealed DC contactor as claimed in claim 1, wherein the first magnetic steel is configured as a magnetic conductive sheet, and the magnetic conductive sheet is configured as a U-shaped structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011427415.9A CN112447448A (en) | 2020-12-07 | 2020-12-07 | Miniature non-sealing direct current contactor arc extinguishing structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011427415.9A CN112447448A (en) | 2020-12-07 | 2020-12-07 | Miniature non-sealing direct current contactor arc extinguishing structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112447448A true CN112447448A (en) | 2021-03-05 |
Family
ID=74739888
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011427415.9A Pending CN112447448A (en) | 2020-12-07 | 2020-12-07 | Miniature non-sealing direct current contactor arc extinguishing structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112447448A (en) |
-
2020
- 2020-12-07 CN CN202011427415.9A patent/CN112447448A/en active Pending
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Effective date of registration: 20220119 Address after: 100000 No. 106, unit 2, building 5, zone 1, yuandayuan, Century City, Haidian District, Beijing Applicant after: Rong Guoren Address before: 100094 209, 2nd floor, building 2, South Tangjialing village, Haidian District, Beijing Applicant before: Beijing tongnai Technology Co.,Ltd. |