CN212461511U

CN212461511U - Electric contact and vacuum arc-extinguishing chamber

Info

Publication number: CN212461511U
Application number: CN202021068350.9U
Authority: CN
Inventors: 骆虎; 曹小军; 许铁军
Original assignee: Shaanxi Baoguang Group Co ltd; China XD Electric Co Ltd
Current assignee: Shaanxi Baoguang Group Co ltd; China XD Electric Co Ltd
Priority date: 2020-06-11
Filing date: 2020-06-11
Publication date: 2021-02-02
Anticipated expiration: 2030-06-11

Abstract

The utility model discloses an electrical contact and vacuum interrupter relates to high-pressure vacuum switch technical field. The electric contact comprises a static end contact and a movable end contact, wherein the static end contact and the movable end contact respectively comprise a contact seat, a main contact and an auxiliary arcing contact. The contact seat is provided with path grooves along the circumferential direction at a preset angle, and the directions of the path grooves of the contact seat on the static end contact and the moving end contact are the same; the main contact is discoid, and main contact and auxiliary arcing contact set up in the homonymy of contact seat, and auxiliary arcing contact is located the outer lane of main contact. When the main contacts of the static end contact and the movable end contact are closed, the auxiliary arcing contacts of the static end contact and the movable end contact are in clearance fit. The utility model provides an electric contact is when main contact electrified separation, and electric arc can follow main contact and shift to supplementary arcing contact on to alleviate the ablation on main contact surface, further improved vacuum interrupter's arc ablation resistance, guarantee current-carrying capacity, improve the electricity life-span.

Description

Electric contact and vacuum arc-extinguishing chamber

Technical Field

The utility model relates to a high-pressure vacuum switch technical field especially relates to an electrical contact and vacuum interrupter.

Background

The vacuum arc-extinguishing chamber is a core component of a vacuum switch and requires reliable bearing, closing, opening and closing of rated continuous current and short-circuit fault current.

In the prior art, the adopted contacts are of a single structure no matter the transverse magnetic structure electrode or the longitudinal magnetic structure electrode, the contacts can only bear rated current and short-circuit current in a closed state, and the contacts have good surface quality and smaller contact resistance. When the contact breaks the short-circuit current, the surface of the contact gradually wears due to the ablation of the electric arc. The problems of poor surface quality, increased contact resistance, reduced current carrying capacity, reduced electrical service life and the like of a contact caused by arc ablation exist in the prior art.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an electric contact to alleviate main contact degree of ablation, guarantee main contact surface quality and electric life-span.

To achieve the purpose, the utility model adopts the following technical proposal:

an electrical contact comprising a stationary end contact and a moving end contact, wherein the stationary end contact and the moving end contact each comprise:

the contact seat is provided with path grooves along the circumferential direction at a preset angle, and the directions of the path grooves of the contact seat on the static end contact and the moving end contact are the same;

the contact device comprises a main contact and an auxiliary arcing contact, wherein the main contact is disc-shaped, the main contact and the auxiliary arcing contact are arranged on the same side of a contact seat, and the auxiliary arcing contact is positioned on the outer ring of the main contact;

and when the main contacts of the static end contact and the movable end contact are closed, the auxiliary arcing contacts of the static end contact and the movable end contact are in clearance fit.

Optionally, the gap comprises a radial gap and an axial gap.

Optionally, in the static end contact and the moving end contact, the auxiliary arcing contact of one of the static end contact and the moving end contact is provided with a boss, and the auxiliary arcing contact of the other of the static end contact and the moving end contact is provided with a groove.

Optionally, when the main contacts of the static end contact and the moving end contact are closed, the height H of the boss entering the groove is 2mm or more and 4mm or less, and the radial gap L1 is: l1 is not more than 2mm, and the axial gap L2 is: l2 is less than or equal to 2 mm.

Optionally, one end of the contact seat is provided with an accommodating cavity, one side of the main contact is provided with a first step, and the first step is connected with the inner wall of the accommodating cavity in a matching manner.

Optionally, the outer wall of the accommodating cavity is provided with a second step, and the auxiliary arcing contact is in fit connection with the second step.

Optionally, the stationary contact and the moving contact further include a supporting member, and the supporting member is disposed between the main contact and the contact block.

Optionally, the primary contact is made of a copper chromium alloy.

Optionally, the auxiliary arcing contact is made of a copper-chromium alloy or a copper-tungsten alloy.

Another object of the utility model is to provide a vacuum interrupter to the realization had both guaranteed vacuum interrupter current-carrying capacity and breaking capacity, had improved its resistant electric arc ablation ability and electric life-span again.

a vacuum interrupter including the electrical contact.

The utility model has the advantages that:

the utility model provides an electric contact sets up supplementary arcing contact through the outer lane at main contact, and there is the clearance in the supplementary arcing contact of quiet end contact and movable end contact when main contact is closed for supplementary arcing contact need not to bear rated continuous current and short-circuit current. The contact seat is provided with a path groove along the circumferential direction at a preset angle, and the directions of the path grooves of the contact seat on the static end contact and the moving end contact are the same, so that when the main contact is separated in an electrified manner, a generated magnetic field is parallel to the direction of an electric arc, and the magnetic field force restrains the electric arc to keep a diffusion form. Through the design of the fit clearance of the auxiliary arcing contact, the clearance is obviously smaller than the clearance of the main contact within a certain time after the main contact is separated, so that electric arc can be transferred from the main contact to the auxiliary arcing contact, the ablation on the surface of the main contact is reduced, the electric arc ablation resistance of the vacuum arc extinguish chamber is further improved, the current carrying capacity is ensured, and the electric service life is prolonged.

The utility model provides a vacuum interrupter uses foretell electrical contact, through introducing supplementary arcing contact, alleviates the ablation on main contact surface to improved vacuum interrupter's resistant electric arc ablation ability, guaranteed current-carrying capacity, improved the electric life-span.

Drawings

Fig. 1 is a schematic structural diagram of an electrical contact according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a main contact of an electrical contact according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a contact block of an electrical contact according to an embodiment of the present invention;

figure 4 is a schematic diagram of an electrical contact according to one embodiment of the present invention when the main contact is closed;

fig. 5 is a schematic diagram of an electrical contact according to an embodiment of the present invention when the main contacts are electrically separated;

fig. 6 is a schematic view of a clearance fit structure of the electrical contact according to an embodiment of the present invention, after the main contact is electrically separated, before the groove and the boss of the auxiliary arcing contact are failed in fit;

fig. 7 is a schematic view of a gap structure of the electrical contact after the main contact is electrically separated and the groove and the boss of the auxiliary arcing contact are matched and disabled.

In the figure:

100. a stationary end contact; 200. a moving end contact;

1. a contact seat; 2. a main contact; 3. an auxiliary arcing contact; 4. a support member; 5. a conductive rod;

11. a second step; 12. a path slot; 21. a first step; 22. a radial slot.

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Wherein the terms "first position" and "second position" are two different positions.

Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "secured" are to be construed broadly and encompass, for example, both fixed and removable connections; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

Unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may include the first feature being in direct contact with the second feature, or may include the first feature being in direct contact with the second feature but being in contact with the second feature by another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The technical solution of the present invention is further explained by the following embodiments with reference to the accompanying drawings.

In order to ensure that the arc energy is uniformly distributed on the surface of the contact in the switching-on and switching-off process and avoid the contact from being locally seriously ablated and melted to cause switching-off failure and electric service life reduction, a flat-plate structure contact, a transverse magnetic structure contact and a longitudinal magnetic structure contact can be adopted according to different required switching-on and switching-off currents.

The flat-plate contact is mainly suitable for the condition without short-circuit on-off requirements, the on-off current of the flat-plate contact is small, electric arcs among the contacts are in a diffusion state in the on-off process, and the contact surface is ablated uniformly in the electric arc combustion process. Therefore, the electrode does not need a complex structure, and only a flat contact is needed to meet the requirement. The flat structure contact and the conducting rod are directly welded together.

The transverse magnetic structure contact and the longitudinal magnetic structure contact are mainly suitable for the condition with short circuit breaking requirements. Because the breaking current is large, under the condition of no magnetic field restriction, vacuum arcs between the contacts become a gathering form and move slowly on the surfaces of the contacts, and local ablation and melting on the surfaces of the contacts are aggravated, so that breaking failure is caused. By adopting the transverse magnetic structure contact or the longitudinal magnetic structure contact, the corresponding magnetic field can be generated by designing the current path when the current flows between the electrodes, and the control of the electric arc is realized. When current flows through the transverse magnetic structure contact, the generated magnetic field is perpendicular to the direction of the electric arc, and the magnetic field force drives the concentrated electric arc to move at high speed on the surface of the contact, so that the contact is prevented from being locally and seriously ablated and melted. Common transverse magnetic contacts have a cup-shaped structure and a spiral groove structure. When the longitudinal magnetic structure contact passes through current, the generated magnetic field is parallel to the direction of the electric arc, and the magnetic field force restrains the electric arc to keep a diffusion state, so that the energy of the electric arc is uniformly distributed on the surface of the contact, and the local serious ablation and melting of the surface of the contact are avoided. Common longitudinal magnetic structure contacts are cup-shaped structures, coil structures and the like.

The utility model discloses utilize the magnetic field force restraint electric arc that the contact of indulging the magnetic structure produced when the electric current flows through to keep the characteristic of diffusion form, provide a new electrical contact, when improving the current-carrying ability, reduced the burning loss degree of main contact when breaking short-circuit current.

Example one

As shown in fig. 1 to 5, the present embodiment provides an electrical contact, which includes a stationary contact 100 and a moving contact 200, wherein the stationary contact 100 and the moving contact 200 each include a contact block 1, a main contact 2, and an auxiliary arcing contact 3. The contact seat 1 is provided with path slots 12 along the circumferential direction at a preset angle, and the directions of the path slots 12 of the contact seat 1 on the static end contact 100 and the moving end contact 200 are the same; the main contact 2 is disc-shaped, the main contact 2 and the auxiliary arcing contact 3 are arranged on the same side of the contact seat 1, and the auxiliary arcing contact 3 is positioned on the outer ring of the main contact 2. When the main contacts 2 of the static end contact 100 and the movable end contact 200 are closed, the auxiliary arcing contacts 3 of the static end contact 100 and the movable end contact 200 are in clearance fit.

In the electrical contact provided by the embodiment, the auxiliary arcing contact 3 is arranged on the outer side of the main contact 2, and the auxiliary arcing contact 3 of the static end contact 100 and the movable end contact 200 has a gap when the main contact 2 is closed, so that the auxiliary arcing contact 3 does not need to bear rated continuous current and short-circuit current. The contact seat 1 is provided with path slots 12 along the circumferential direction at a preset angle, and the directions of the path slots 12 of the contact seat 1 on the static end contact 100 and the moving end contact 200 are the same, so that when the main contact 2 is separated in an electrified manner, the generated magnetic field is parallel to the direction of an electric arc, and the magnetic field force restrains the electric arc to keep a diffusion state. The fit clearance of the auxiliary arcing contact 3 is obviously smaller than the clearance of the main contact 2 within a certain time after the main contact 2 is separated, electric arc can be transferred from the main contact 2 to the auxiliary arcing contact 3, so that the ablation on the surface of the main contact 2 is reduced, the electric arc ablation resistance of the vacuum arc extinguish chamber is further improved, the current carrying capacity is ensured, and the electric service life is prolonged.

In this embodiment, the preset angle of the path slot 12 on the contact base 1 is not particularly limited, and only needs to satisfy the requirement that when current passes through, a longitudinal magnetic field can be generated between the contacts, so that the arc is diffused to the outer ring of the main contact 2.

Alternatively, the main contact 2 is made of a copper-chromium alloy. The auxiliary arcing contact 3 is made of a copper-chromium alloy or a copper-tungsten alloy. The main contact 2 adopts a copper-chromium alloy material with better conductivity and chromium content. For example, the materials such as CuCr50, CuCr40, CuCr30, etc. have the preparation processes of infiltration, powder mixing, fusion casting, arc melting, etc. The auxiliary arcing contact 3 is made of copper-tungsten alloy which is resistant to arc erosion or copper-chromium alloy with high chromium content and the like, which is different from the main contact 2. Tungsten-based materials such as WCu10 and CwuWC are adopted, or the main contact 2 is CuCr30, and the auxiliary arcing contact 3 is CuCr 50.

Optionally, as shown in fig. 2 and fig. 3, an accommodating cavity is provided at one end of the contact block 1, a first step 21 is provided at one side of the main contact 2, and the first step 21 is in fit connection with an inner wall of the accommodating cavity. The outer wall of the accommodating cavity is provided with a second step 11, and the auxiliary arcing contact 3 is connected with the second step 11 in a matching way. Generally, the contacts capable of generating a longitudinal magnetic field have a cup-shaped structure and a coil-shaped structure, when current passes through the contacts, magnetic field distribution with large longitudinal component is generated among the contacts, so that electric arcs can be kept in a diffusion state, concentration is avoided, and the electric arcs are easier to extinguish when alternating current passes through the contacts. In the embodiment, a cup-shaped longitudinal magnetic structure is adopted, the main contact 2 is provided with a radial groove 22 along the radial direction, and the radial groove 22 is arranged to extinguish the arc when the alternating current flows through zero. One side of main contact 2 sets up to the step face for with the cavity location of contact seat 1 opening side, then through welded mode with main contact 2 and contact seat 1 fixed connection. The auxiliary arcing contact 3 is arranged on the outer ring of the main contact 2, so that when the main contact 2 is powered off, electric arcs can be transferred from the main contact 2 to the auxiliary arcing contact 3 under the action of magnetic field force, and ablation on the surface of the main contact 2 is reduced. Of course, in other embodiments, a coil longitudinal magnetic structure or other longitudinal magnetic structures may be used.

Optionally, as shown in fig. 4-5, the stationary contact 100 and the moving contact 200 further include a support 4 and a conductive rod 5, and the support 4 is disposed between the main contact 2 and the contact block 1. The conductive rod 5 is fixedly connected with the bottom end of the contact seat 1. In this embodiment, the supporting member 4 is configured as a hollow cylinder structure, and the two ends are respectively provided with a first supporting surface and a second supporting surface, the first supporting surface abuts against the bottom of the accommodating cavity of the contact holder 1, and the second supporting surface abuts against the main contact 2 to support the main contact 2. The bottom of the contact seat 1 is provided with a mounting hole, one end of the conductive rod 5 is provided with a guide post, and the guide post is matched with the mounting hole to install the conductive rod 5 at the outer side of the bottom of the contact seat 1 and is connected with the mounting hole in a welding mode. Of course, in other embodiments, a threaded hole may be formed in the bottom of the contact block 1, and a stud is disposed at one end of the conductive rod 5, so as to connect the conductive rod 5 and the contact block 1 through a threaded connection.

Preferably, as shown in fig. 4, the clearance includes a radial clearance and an axial clearance. In both the stationary end contact 100 and the movable end contact 200, the auxiliary arcing contact 3 of one of the stationary end contact and the movable end contact is provided with a boss, and the auxiliary arcing contact 3 of the other one of the stationary end contact and the movable end contact is provided with a groove. In this embodiment, the auxiliary arcing contact 3 of the stationary end contact 100 is provided with a recess, and the auxiliary arcing contact 3 of the movable end contact 200 is provided with a boss. Of course, in other embodiments, a boss may be provided on the auxiliary arcing contact 3 of the stationary end contact 100, a groove may be provided on the auxiliary arcing contact 3 of the movable end contact 200, or other mating structures with radial and axial clearances may be provided.

When the main contact 2 is closed, the boss of the auxiliary arcing contact 3 with the boss extends into the groove of the auxiliary arcing contact 3 with the groove, the front face and the side face of the boss and the groove are provided with set gaps, the gap on the front face is an axial gap, and the gap on the side face is a radial gap. When the gap of the main contact 2 is larger than the minimum gap between the auxiliary arcing contacts 3 when the main contact 2 is electrically disconnected, the arc is more easily transferred from the main contact 2 to the auxiliary arcing contacts 3 to reduce ablation of the surface of the main contact 2. Of course, in other embodiments, no radial gap may be provided, by which the auxiliary arcing contact 3 need not carry the rated continuous and short-circuit currents when the main contact 2 is closed. When the main contact 2 is electrified and separated, the generated magnetic field is parallel to the direction of the electric arc, the magnetic field force restrains the electric arc to keep a diffusion state, and the electric arc can be transferred from the main contact 2 to the auxiliary arcing contact 3.

As shown in fig. 5, when the main contacts 2 are electrically separated, an arc is generated between the main contacts 2, the axial gap of the auxiliary arcing contacts 3 is increased along with the increase of the gap of the main contacts 2, the radial gap is unchanged before the fit failure of the groove and the boss, and the minimum gap of the auxiliary arcing contacts is the radial gap. The minimum clearance of the auxiliary arcing contact gradually increases after the groove and the boss are in fit failure. In the process where the gap of the main contact 2 is greater than the minimum gap of the auxiliary arcing contacts, the arc is readily arcing between the auxiliary arcing contacts 3, thereby mitigating the erosion of the main contact 2 by the arc. Therefore, the burning loss degree of the main contact 2 in the switching-on and switching-off process is reduced by introducing the auxiliary arcing contact 3, so that the main contact 2 is easier to keep better surface quality, and the current carrying capacity of the vacuum arc extinguish chamber is favorably ensured.

Preferably, when the main contacts 2 of the static end contact 100 and the movable end contact 200 are closed, the height H of the boss entering the groove is more than or equal to 2mm and less than or equal to 4mm, and the radial clearance L1 is as follows: l1 is less than or equal to 2mm, and the axial clearance L2 is: l2 is less than or equal to 2 mm. In this embodiment, when the main contacts 2 of the stationary contact 100 and the moving contact 200 are closed, the height H of the boss entering the groove is 3mm, the radial clearance L1 is 2mm, and the axial clearance L2 is 2 mm. Table 1 is a table of minimum gap variation of the auxiliary arcing contact in the process of closing the main contact and separating the main contact from the live contact in the present embodiment.

In table 1, in the process of electrically separating the main contacts 2 of the stationary contact 100 and the movable contact 200, the gap between the main contacts 2 is D, and is in the range of 0mm < D < 10mm, when 0mm < D < 3mm, as shown in fig. 6, the grooves and the bosses are matched, and the height of the bosses inserted into the grooves is H-D. When 2mm < D < 3mm, the main contact 2 gap D is greater than the minimum gap Lmin between the auxiliary arcing contacts 3, which is 2mm for the radial gap L1 of the auxiliary arcing contacts 3. When D is more than 3mm and less than 10mm, as shown in FIG. 7, the fit between the groove and the boss fails and mutually failsSeparated from each other, the minimum clearance between the auxiliary arcing contacts 3 is Lmin,

as can be seen from table 1, Lmin is less than the main contact 2 gap D. Therefore, when D is larger than 2mm and smaller than 10mm, the electric arc is easy to burn among the auxiliary arcing contacts 3 in the surface burning process of the main contact 2, thereby reducing the ablation of the electric arc on the main contact 2.

TABLE 1

The embodiment also provides a vacuum arc-extinguishing chamber comprising the electric contact. By introducing the auxiliary arcing contact 3, ablation of the surface of the main contact 2 is reduced. Thereby improving the arc ablation resistance of the vacuum arc extinguish chamber, ensuring the current carrying capacity and prolonging the electric service life.

Example two

The difference between this embodiment and the first embodiment is:

in the present embodiment, when the main contacts 2 of the stationary contact 100 and the moving contact 200 are closed, the height H of the boss entering the groove is 3mm, the radial clearance L1 is 1mm, and the axial clearance L2 is 2 mm. Table 2 is a table of minimum gap variation of the auxiliary arcing contact in the process of closing the main contact and separating the main contact from the live contact in the present embodiment.

In table 2, in the process of electrically separating the main contacts 2 of the stationary contact 100 and the movable contact 200, the gap between the main contacts 2 is D, and is in the range of 0mm < D < 10mm, and when 0mm < D < 3mm, as shown in fig. 6, the grooves and the bosses are matched, and the height of the bosses inserted into the grooves is H-D. When 1mm < D < 3mm, the main contact 2 gap D is greater than the minimum gap Lmin between the auxiliary arcing contacts 3, which is 1mm for the radial gap L1 of the auxiliary arcing contacts 3. When D is more than 3mm and less than 10mm, as shown in figure 7, the matching between the groove and the boss is invalid and mutually separated, the minimum clearance between the auxiliary arcing contacts 3 is Lmin,

as can be seen from table 2, Lmin is less than the main contact 2 gap D. Therefore, when D is larger than 1mm and smaller than 10mm, the electric arc is easy to burn among the auxiliary arcing contacts 3 in the surface burning process of the main contact 2, thereby reducing the ablation of the electric arc on the main contact 2.

TABLE 2

EXAMPLE III

The difference between this embodiment and the first embodiment is:

in this embodiment, when the main contacts 2 of the stationary contact 100 and the moving contact 200 are closed, the height H of the boss entering the groove is 4mm, the radial clearance L1 is 1mm, and the axial clearance L2 is 2 mm. Table 3 is a table of minimum gap variation of the auxiliary arcing contact in the process of closing the main contact and separating the main contact from the live contact in the present embodiment.

In table 3, in the process of electrically separating the main contacts 2 of the stationary contact 100 and the movable contact 200, the gap between the main contacts 2 is D, and is in the range of 0mm < D < 10mm, and when 0mm < D < 4mm, as shown in fig. 6, the groove and the boss are engaged with each other, and the height of the boss inserted into the groove is H-D. When 1mm < D < 4mm, the main contact 2 gap D is greater than the minimum gap Lmin between the auxiliary arcing contacts 3, which is 1mm for the radial gap L1 of the auxiliary arcing contacts 3. When D is more than 4mm and less than 10mm, as shown in figure 7, the matching between the groove and the boss is invalid and mutually separated, the minimum clearance between the auxiliary arcing contacts 3 is Lmin,

as can be seen from table 3, Lmin is smaller than the main contact 2 gap. Therefore, when D is larger than 1mm and smaller than 10mm, the electric arc is easy to burn among the auxiliary arcing contacts 3 in the surface burning process of the main contact 2, thereby reducing the ablation of the electric arc on the main contact 2.

TABLE 3

Example four

The difference between this embodiment and the first embodiment is:

in the present embodiment, when the main contacts 2 of the stationary contact 100 and the moving contact 200 are closed, the height H of the boss entering the groove is 4mm, the radial clearance L1 is 2mm, and the axial clearance L2 is 2 mm. Table 4 is a table of minimum gap variation of the auxiliary arcing contact in the process of closing the main contact and separating the main contact from the live contact in the present embodiment.

In table 4, in the process of electrically separating the main contacts 2 of the stationary contact 100 and the movable contact 200, the gap between the main contacts 2 is D, and is in the range of 0mm < D < 10mm, and when 0mm < D < 4mm, as shown in fig. 6, the groove and the boss are engaged with each other, and the height of the boss inserted into the groove is H-D. When D is more than 2mm and less than 4mm, the gap D of the main contact 2 is more than the minimum gap Lmin between the auxiliary arcing contacts 3, the minimum gap Lmin between the auxiliary arcing contacts 3 is 1mm which is the radial gap L1 of the auxiliary arcing contacts 3, when D is more than 4mm and less than 10mm, as shown in fig. 7, the fit between the groove and the boss is failed and separated from each other, and the minimum gap between the auxiliary arcing contacts 3 is Lmin.

As can be seen from table 4, Lmin is less than the main contact 2 gap D. Therefore, when D is larger than 2mm and smaller than 10mm, the electric arc is easy to burn among the auxiliary arcing contacts 3 in the surface burning process of the main contact 2, thereby reducing the ablation of the electric arc on the main contact 2.

TABLE 4

The above description is only for the preferred embodiment of the present invention, and for those skilled in the art, there are variations on the detailed description and the application scope according to the idea of the present invention, and the content of the description should not be construed as a limitation to the present invention.

Claims

1. An electrical contact comprising a stationary end contact (100) and a moving end contact (200), characterized in that the stationary end contact (100) and the moving end contact (200) each comprise:

the contact structure comprises a contact seat (1), wherein path grooves (12) are formed in the contact seat (1) at a preset angle along the circumferential direction, and the directions of the path grooves (12) of the contact seat (1) on a static end contact (100) and a movable end contact (200) are the same;

the contact device comprises a main contact (2) and an auxiliary arcing contact (3), wherein the main contact (2) is disc-shaped, the main contact (2) and the auxiliary arcing contact (3) are arranged on the same side of a contact seat (1), and the auxiliary arcing contact (3) is positioned on the outer ring of the main contact (2);

when the main contacts (2) of the static end contact (100) and the movable end contact (200) are closed, the auxiliary arcing contacts (3) of the static end contact (100) and the movable end contact (200) are in clearance fit.

2. The electrical contact of claim 1, wherein the gap comprises a radial gap and an axial gap.

3. Electrical contact according to claim 2, characterised in that the auxiliary arcing contact (3) of one of the stationary end contact (100) and the moving end contact (200) is provided with a boss and the auxiliary arcing contact (3) of the other is provided with a recess.

4. Electrical contact according to claim 3, characterized in that, when the main contact (2) of the stationary end contact (100) and the moving end contact (200) is closed, the height H of the projection into the recess is 2mm ≦ H ≦ 4mm, the radial clearance L1 being: l1 is not more than 2mm, and the axial gap L2 is: l2 is less than or equal to 2 mm.

5. The electrical contact according to claim 1, characterized in that one end of the contact block (1) is provided with a receiving cavity, one side of the main contact (2) is provided with a first step (21), and the first step (21) is in fit connection with the inner wall of the receiving cavity.

6. Electrical contact according to claim 5, characterized in that the outer wall of the receiving chamber is provided with a second step (11), the auxiliary arcing contact (3) being in mating connection with the second step (11).

7. Electrical contact according to claim 6, characterized in that the stationary end contact (100) and the moving end contact (200) further comprise a support (4), the support (4) being arranged between the main contact (2) and the contact block (1).

8. Electrical contact according to any one of claims 1-7, characterised in that the main contact (2) is made of a copper-chromium alloy.

9. Electrical contact according to any one of claims 1-7, characterised in that the auxiliary arcing contact (3) is made of a copper-chromium alloy or a copper-tungsten alloy.

10. Vacuum interrupter, characterized in that it comprises an electrical contact according to any of claims 1-9.