CN211350491U - Porous skeleton bridge type contact structure of direct current contactor - Google Patents

Abstract

The utility model belongs to the direct current contactor field relates to electrical contact material, contact structure and contact performance, specifically is a direct current contactor's porous skeleton bridge type contact structure. Comprises a moving contact structure and a static contact structure; the device is characterized in that the moving contact structure and the static contact structure are both composed of a plurality of Cu/W cubic units; the Cu/W cubic unit comprises a cubic W frame and a Cu core arranged in the W frame. The utility model discloses new contact structure can increase contact structure's thermal conductivity and conductivity, and increase contact surface heat dissipation reduces the ablation of electric arc to the contact surface to reduce metal steam's production, extinguish fast to electric arc and play the promotion effect, contact performance promotes, increase of service life.

Description

Porous skeleton bridge type contact structure of direct current contactor

Technical Field

The invention belongs to the field of direct current contactors, relates to an electrical contact material, a contact structure and contact performance, and particularly relates to a bridge type contact structure.

Background

Due to gradual depletion of conventional energy, new energy vehicles powered by new energy fuels are rapidly developed, and the industrial application fields mainly comprise direct-current power distribution systems. Therefore, the dc contactor related to the dc cut-off plays a crucial role in the safe and reliable power supply of the dc power supply system. The direct current contactor can carry out frequent connection and disconnection on a direct current main circuit and a high-capacity control circuit, and can realize timing operation, interlocking control, various quantitative control and voltage loss and undervoltage protection by matching with a relay. With the rapid development of the power industry in China, the requirements on the running performance and the quality of a switching electric appliance product are higher and higher, the contactor is used as an important control electric appliance, and the contact stability of a contact system of the contactor has important significance on the circuit safety.

The electric contact is an important contact element in the switches of instruments and meters and electrical appliances and is responsible for the tasks of switching on, carrying and breaking current, so that the contact characteristics of the contact directly influence the working performance of the low-voltage control electrical appliance, and further influence the safe and reliable operation of an electrical control system. The contact structure of the contactor used at present mostly adopts a bridge type contact structure, powder alloy is used as a manufacturing material, and various components are mixed together disorderly. The contact plays a role in connection and disconnection, and the contact material and the contact structure are required to have the following properties: 1. as high electrical and thermal conductivity and thermal stability as possible; 2. good mechanical property, good plasticity, toughness and wear resistance; 3. good chemical performance; 4. excellent fusion welding resistance; 5. excellent arc burning resistance, fusion welding resistance, electric shock resistance and lower contact resistance. The vacuum contact material is also required to have a small cutoff value, high compressive strength and high breaking capacity.

Because the contact structure determines the service life and the development of the switching device to a great extent, a new ordered skeleton structure contact system is designed, so that the novel contact structure can reduce the contact vibration, improve the electrical conductivity and the thermal conductivity of the contact, the arc burning resistance and the fusion welding resistance, further increase the switching-on and switching-off capacity of the contactor and prolong the service life.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a porous framework bridge type contact structure of a direct current contactor. In the following scheme, Cu represents copper and W represents tungsten.

In order to achieve the purpose, the invention adopts the following technical scheme that the device comprises a movable contact structure and a fixed contact structure; the device is characterized in that the moving contact structure and the static contact structure are both composed of a plurality of Cu/W cubic units; the Cu/W cubic unit comprises a cubic W frame and a Cu core arranged in the W frame.

Furthermore, the cubic W frame is of a cubic structure, a cavity is arranged in the cubic structure, and square through holes are formed in the upper surface, the lower surface, the left surface, the right surface, the front surface and the rear surface of the cubic structure; the six through holes are communicated with the cavity.

Furthermore, the through hole on the upper side of the cubic structure is opposite to the through hole on the lower side, the through hole on the left side of the cubic structure is opposite to the through hole on the right side, and the through hole on the front side of the cubic structure is opposite to the through hole on the rear side; the six through holes are identical in shape and size, and the center of each through hole is concentric with the center of the cavity.

Furthermore, the cavity and the through hole of the cubic structure are cubic.

Further, the Cu core has a shape which can be filled with the cavities and the through holes of the cubic structure.

Further, the Cu core in both the cubic W frame and the W frame is dense.

Furthermore, the plurality of Cu/W cubic units are connected by fusion welding and diffusion (welding).

Compared with the prior art, the invention has the beneficial effects.

In the invention, the arc ablation resistance is mainly provided by the tungsten phase, the hardness, the strength and the high-temperature strength are obviously improved because the tungsten phase is connected along three axial directions, and the copper with lower melting point in the composite material is separated in countless fine areas by the tungsten and is difficult to melt because the tungsten frames are mutually communicated and interwoven in three-dimensional space, thereby having excellent arc ablation resistance.

The electric conduction and heat conduction performance, the plasticity and the toughness of the composite material are mainly provided by the copper phase, and the copper blocks are orderly stacked and arranged along three axial directions and are mutually communicated in a three-dimensional space, so that the Cu/W cubic unit shows excellent electric conduction and heat conduction performance along the direction, and the improvement of the electric conduction and heat conduction performance is beneficial to reducing the generation and accumulation of heat, thereby further improving the arc ablation resistance of the composite material.

The novel contact structure can increase the heat conductivity and the electric conductivity of the contact structure, increase the heat dissipation of the surface of the contact, and reduce the ablation of electric arc on the surface of the contact, thereby reducing the generation of metal steam, playing a role in promoting the quick extinguishing of the electric arc, improving the performance of the contact and prolonging the service life.

Drawings

The invention is further described with reference to the following figures and detailed description. The scope of the invention is not limited to the following expressions.

Figure 1 is a schematic view of a prior art bridgehead contact configuration.

Fig. 2 is a cross-sectional view of a two-dimensional disordered distribution of copper-tungsten material.

Fig. 3 is a two-dimensional ordered distribution cross-sectional view of copper-tungsten material.

Fig. 4 is a cross-sectional view of a more regular distribution of copper-tungsten material in two dimensions.

FIG. 5 is a schematic diagram of a Cu/W cube cell of the present invention.

FIG. 6 is a schematic view of a multiple cube W frame of the present invention.

Fig. 7 is a schematic view of an overall frame of a static contact structure composed of cubic units according to the present invention.

Fig. 8 is a schematic view of the whole framework of the movable contact structure composed of cubic units.

Fig. 9 is a schematic view of the overall structure of a cubic contact according to the present invention.

In the figure, 1 is an upper end cover, 2 is a fixed static contact column, 3 is a static contact, 4 is a moving contact, 5 is a moving contact bridge, 6 is tungsten, 7 is copper, 8 is a contact structure, and 9 is a cubic W frame.

Detailed Description

The existing bridge contact structure is shown in fig. 1, and comprises a movable contact structure and a fixed contact structure, wherein: the contact structure comprises an upper end cover 1, a fixed static contact column 2 and a static contact 3, and the movable contact structure comprises a movable contact 4 and a movable contact bridge 5.

As shown in fig. 2, the mixed distribution of the equal areas of the copper and tungsten metal materials is the same as that of the entire square, where each small square constituting the large square is the same area, black is tungsten 6, and white is copper 7; as shown in fig. 3, the copper and tungsten metal are regularly distributed, and one row of tungsten 6 and one row of copper 7 are distributed in the whole large quadrangle in equal area; as shown in fig. 4, the two-phase metal distribution is relatively regular, and the tungsten metal material forms a frame 11, in which the copper material 10 is wrapped. The calculation results show that the current obtained from the different graphs of fig. 2-4 is 3.3490E5A, 3.9312E5A and 3.3771E5A, and thus, the ordered structure indeed greatly improves the conductivity. Finding this rule and using it into the present design is a technical difficulty.

As shown in fig. 5-9, the present invention includes a moving contact structure and a stationary contact structure; the device is characterized in that the moving contact structure and the static contact structure are both composed of a plurality of Cu/W cubic units; the Cu/W cubic unit comprises a cubic W frame and a Cu core arranged in the W frame.

Furthermore, the cubic W frame is of a cubic structure, a cavity is arranged in the cubic structure, and square through holes are formed in the upper surface, the lower surface, the left surface, the right surface, the front surface and the rear surface of the cubic structure; the six through holes are communicated with the cavity; the center of each through hole is concentric with the center of the cavity.

Further, the center of the square through hole is collinear with the center of the cavity.

Furthermore, the through hole on the upper side of the cubic structure is opposite to the through hole on the lower side, the through hole on the left side of the cubic structure is opposite to the through hole on the right side, and the through hole on the front side of the cubic structure is opposite to the through hole on the rear side; and the shapes and the sizes of the six through holes are the same.

Furthermore, the cavity and the through hole of the cubic structure are cubic.

Further, the Cu core is in a shape which can be filled in the cavities and the through holes of the cubic structure.

Further, the Cu core in both the cubic W frame and the W frame is dense.

Furthermore, the plurality of Cu/W cubic units are connected by fusion welding and diffusion (welding).

In addition, the process of injecting the Cu core into the W frame is: filling copper powder into the W frame at 600-800 deg.C^oAnd (4) vacuum sintering for 4-8 h in the range of C, and cooling in a furnace.

The invention aims to provide a double-break bridge type contact structure, wherein the contact is used as the weakest part of the electrical appliance, and the performance of the contact is important for prolonging the electrical service life and improving the reliability of a direct current contactor. According to the influence of reducing the resistance of the solid solution by ordering, the existing contact structure is improved, and the two-phase alloy materials for manufacturing the contact are distributed in the contact structure in order, so that the conductive capacity of the contact is improved. The framework structure reduces the bounce of the contact and improves the breaking capacity of the contact.

From the conducting angle, the conducting process of the material can be regarded as the migration motion of free electrons from 1 lattice to the other 1 lattice in the reverse electric field direction under the action of the external electric field, and the conducting property of the contact material is determined by all conducting units together. Generally, when the conductive particles contact each other to form a chain network, or when the gaps between the conductive particles are small, a current channel is formed. The more conductive particles that are in contact, the denser the network, and the smaller the gaps between the particles, the higher the composite conductivity. The special skeleton structures are communicated with each other in a three-dimensional space, and the orderly connection of the alloy materials is compared with the disordered mixing of the materials, so that the good conductive channel formed by the ordered structures has greatly improved conductive capacity, and the conductivity is effectively improved in the contact breaking process. Ordering makes the atoms in the crystal lattice more orderly and regularly arranged, so that the distortion of the crystal lattice is reduced, the scattering of conduction electrons is reduced, and the resistance is reduced. The invention combines the ordered structure into the contact, in order to rapidly switch on and off the current, the conductive particles which are mutually contacted form a continuous conductive channel according to the theory of the conductive channel, thereby increasing the electric conduction and heat conduction capability of the contact.

Also, the contacts spring like during closing, known as mechanical vibration of the contacts. The bounce of the contact can generate electric arcs, so that the contact is subjected to fusion welding and burning loss, and the action of the contact is seriously influenced; the framework structure can slow down the bouncing and energy-absorbing functions of the contact. Because the framework structure also has good vibration reduction effect, the contact is often burnt and ablated due to the arcing of the contact caused by mechanical vibration in the breaking process of the contact, the service life of the contact is shortened, the vibration of the contact is effectively reduced by the structure, and the energy is absorbed.

Further, at present, copper-based contact materials have been widely studied in addition to the silver-based contact materials used in the largest amounts, and Cu has a conductivity similar to that of Ag but is relatively low in cost. The copper-based contact material has relatively excellent electrical property and is applied to medium and high voltage electric appliances. Copper-based contact materials are mainly classified into Cu-W-based, Cu-Cr-based, Cu-Bi-based, and rare CuC contacts, Cu/Al2O3 contacts, and the like. The Cu-Bi alloy has good fusion welding resistance, lower shutoff value and certain breaking capacity, but the contact has shorter service life due to low strength and large arc erosion. The Cu-Cr material features high voltage resistance, high breaking capacity, strong suction power, high anticorrosion nature and low cut-off value. Copper-chromium contacts also have significant drawbacks, as do copper-tungsten alloys. The invention integrates Cu and W, Cu has good thermal conductivity and electrical conductivity, W has high density, high strength, high melting point and low expansion coefficient, and the two are not mutually soluble and can not form intermetallic compounds. Meanwhile, the material has the advantages of Cu and W, and has good heat conductivity and electric conductivity, large density and small expansion coefficient.

It should be understood that the detailed description of the present invention is only for illustrating the present invention and is not limited by the technical solutions described in the embodiments of the present invention, and those skilled in the art should understand that the present invention can be modified or substituted equally to achieve the same technical effects; as long as the use requirements are met, the method is within the protection scope of the invention.

Claims (7)

1. A porous framework bridge type contact structure of a direct current contactor comprises a movable contact structure and a fixed contact structure; the device is characterized in that the moving contact structure and the static contact structure are both composed of a plurality of Cu/W cubic units; the Cu/W cubic unit comprises a cubic W frame and a Cu core arranged in the W frame.

2. The porous skeleton bridge contact structure of a direct current contactor as claimed in claim 1, wherein: the cubic W frame is of a cubic structure, a cavity is arranged in the cubic structure, and square through holes are formed in the upper face, the lower face, the left face, the right face, the front face and the rear face of the cubic structure; the six through holes are communicated with the cavity.

3. The porous skeleton bridge contact structure of a direct current contactor as claimed in claim 2, wherein: the through hole on the upper surface of the cubic structure is opposite to the through hole on the lower surface, the through hole on the left surface of the cubic structure is opposite to the through hole on the right surface, and the through hole on the front surface of the cubic structure is opposite to the through hole on the back surface; the six through holes are identical in shape and size, and the center of each through hole is concentric with the center of the cavity.

4. The porous skeleton bridge contact structure of a direct current contactor as claimed in claim 2, wherein: the cavity and the through hole of the cubic structure are both cubic.

5. The porous skeleton bridge contact structure of a direct current contactor as claimed in claim 1, wherein: the Cu core has the shape which can be filled in the cavity and the through hole of the cubic structure.

6. The porous skeleton bridge contact structure of a direct current contactor as claimed in claim 1, wherein: the Cu core in both the cubic W frame and the W frame is dense.

7. The porous skeleton bridge contact structure of a direct current contactor as claimed in claim 1, wherein: and the plurality of Cu/W cubic units are in fusion welding diffusion connection.

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