Magnetic field contact for vacuum arc-extinguishing chamber and manufacturing method thereof

Abstract

The invention relates to a magnetic field contact for a vacuum arc extinguish chamber and a manufacturing method of the magnetic field contact, and belongs to the technical field of vacuum switchs.The magnetic field contact comprises a contact cup, a contact and reinforcing ribs, the contact covers an opening of the contact cup and is fixedly connected with the contact cup, a spiral groove is formed in the circumferential outer wall of the contact cup, and the reinforcing ribs are arranged in the spiral groove. The spiral groove is used for forming a longitudinal or transverse magnetic field, the reinforcing rib is located in the contact cup and fixedly connected with the inner wall of the contact cup, and the outer diameter of the reinforcing rib is the same as the inner diameter of the contact cup where the reinforcing rib is located. The manufacturing process of the contact structure is reduced, and the use amount of silver-copper solder and contact materials is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of vacuum switches, and in particular to a magnetic field contact for a vacuum interrupter and a manufacturing method thereof. Background Art

[0002] Vacuum circuit breakers are important switchgear in medium and high voltage power systems. They have been widely used due to their small size, simple structure, environmental friendliness and maintenance-free.

[0003] In order to improve the breaking capacity of the vacuum interrupter, a transverse or longitudinal magnetic field is usually applied to the gap between the two contact structures of the vacuum interrupter to control the vacuum arc. In addition, in order to reduce the temperature rise of the vacuum circuit breaker when it is running under load, the resistance of the conductive circuit of the vacuum interrupter should not be too high.

[0004] In practical applications, cup-shaped contacts have been widely used due to their excellent magnetic field control capabilities and low loop resistance. During the contact production process, an inclined groove is opened on the cup-shaped side wall of the contact. The inclined groove opens the cup-shaped side wall, thereby increasing the magnetic field distribution range and improving the speed and efficiency of arc extinguishing.

[0005] However, the inclined groove mills through the cup-shaped side wall of the contact. In the subsequent contact welding process, there are defects such as poor welding due to deformation of the cup-shaped side wall of the contact and the flow of solder into the inclined groove. Summary of the invention

[0006] In order to ensure the finished product quality of the cup-shaped contact structure and improve the mechanical strength and stability of the contact structure, the present application provides a magnetic field contact for a vacuum arc chamber and a manufacturing method thereof.

[0007] In a first aspect, the present application provides a magnetic field contact for a vacuum interrupter, which adopts the following technical solution: A magnetic field contact for a vacuum interrupter comprises a contact cup, a contact and a reinforcing rib, wherein the contact covers a port of the contact cup and an end face of the reinforcing rib and is fixedly connected to the contact cup and the reinforcing rib, a spiral groove is provided on the circumferential outer wall of the contact cup, and the spiral groove is used to form a longitudinal or transverse magnetic field, the reinforcing rib is located inside the contact cup and is fixedly connected to the inner wall of the contact cup, and the outer diameter of the reinforcing rib is the same as the inner diameter of the contact cup at the position where the reinforcing rib is located.

[0008] By adopting the above technical solution, the reinforcing rib located inside the contact cup and fixedly connected to the inner wall can significantly enhance the structural strength of the contact cup, making it less likely to deform or be damaged when subjected to external force and internal pressure, thereby improving the mechanical strength and stability of the contact structure. In addition, the outer diameter of the reinforcing rib is the same as the inner diameter of the contact cup at the location where the reinforcing rib is located, thereby ensuring the uniformity of the internal structure of the contact cup and facilitating the uniform distribution of the electric field and the magnetic field.

[0009] Optionally, the spiral groove is opened in a spiral shape along the length direction of the contact cup, and the spiral groove is only opened on the contact cup, that is, the spiral groove is not opened all the way to the contact.

[0010] By adopting the above technical solution, the structure of the cup wall end of the contact cup can be relatively complete without opening all the way to the contact, thereby improving the overall mechanical strength and stability of the contact structure. During the contact closing and disconnecting process, it can withstand greater impact force and contact pressure, reducing the possibility of contact deformation and damage. For example, in a switchgear that is frequently operated, this structure helps to extend the service life of the contact structure. Such a setting also helps to maintain a relatively uniform electric field distribution at the cup wall end of the contact cup, avoiding electric field concentration caused by opening all the way, thereby improving the insulation performance and the stability of the arc extinguishing effect.

[0011] Optionally, the reinforcing rib has a conductivity lower than 5×10 6 Reinforcement ribs made of materials with S / m and magnetic properties less than 1.05.

[0012] By adopting the above technical solution, the reinforcing ribs made of materials with limited magnetic permeability and electrical conductivity are used, so that the influence of the reinforcing ribs on the magnetic field is reduced.

[0013] Optionally, a connecting column and a copper plate are provided on the reinforcing rib, the connecting column is located between the reinforcing rib and the copper plate, one end of the connecting column is fixedly connected to the reinforcing rib, and the other end of the connecting column is fixedly connected to the copper plate, and the copper plate is fixed on the side wall of the contact close to the inside of the contact cup.

[0014] By adopting the above technical solution, the copper plate is set to improve the electrical and thermal conductivity of the contact. This contact structure is used in high-voltage vacuum interrupter. In order to improve the insulation capacity, it is necessary to increase the chromium content and the R angle size of the contact edge. At this time, the contact material is relatively thick. At this time, the copper plate is set to give full play to the electrical and thermal conductivity.

[0015] Optionally, the contact cup is made of copper with a copper content greater than 99.5% or an alloy material with a copper content greater than 90%.

[0016] By adopting the above technical solution, copper has good thermal conductivity, which helps to quickly dissipate the heat generated by the contact during operation, reduce the contact temperature and extend its service life. For example, in a circuit with frequent switching, rapid heat dissipation can reduce the risk of damage to the contact due to overheating. Copper has excellent electrical conductivity, and a high copper content can ensure that the contact cup effectively conducts current in the circuit, reducing energy loss and heat generation. Alloys containing a certain proportion of copper can not only ensure good electrical conductivity, but also provide good mechanical strength and hardness, so that the contact cup can withstand the mechanical stress during switch operation.

[0017] In a second aspect, the present application provides a method for manufacturing a magnetic field contact for a vacuum interrupter, using the following technical solution: A method for manufacturing a magnetic field contact for a vacuum interrupter comprises the following steps: S1. Clean the contact cup and reinforcement ribs; S2. Place the reinforcing rib in the contact cup; S3, preparing contact powder; S4, laser printing is performed to fix the reinforcing ribs to the inner wall of the contact cup by cladding, and the contact cup is processed with different numbers and angles of rotary grooves along the circumferential side wall according to the requirements of the breaking capacity of the vacuum arc extinguishing chamber; S5, performing laser printing on the end surface of the opening end of the contact cup and on the side wall of the copper disk away from the connecting column to form a contact by cladding; S6. Mechanically process the contact surface.

[0018] By adopting the above technical scheme, laser printing technology can achieve more precise energy control and material deposition, so that the formation of microstructure can be better controlled during the melting and solidification process of the material, thereby resulting in a smaller particle size of chromium particles in the formed contact, and the particle size of chromium particles in the contact is smaller than the particle size of chromium particles in the contact processed by the prior art, so that the contact formed by laser printing technology has better insulation ability and better short-circuit breaking ability when applied to the vacuum arc chamber; while manufacturing the contact, other parts of the contact structure are combined with the contact into a whole at one time, without the need to braze the parts with expensive silver-copper solder, which significantly reduces the manufacturing cost; the contact is formed by cladding the open end face of the contact cup and the surface of the copper plate by laser printing technology, which can significantly save the amount of contact material compared with the prior art. In addition, the use of laser printing technology also avoids the quality problem of solder flowing into the chute when the contact is brazed with silver-copper solder.

[0019] Optionally, all laser printing processes are performed in an environment filled with reducing gas or in a vacuum environment.

[0020] By adopting the above technical solution, laser printing is performed in a reducing atmosphere or in a vacuum to avoid oxidation of parts and materials.

[0021] In summary, the present application includes at least one of the following beneficial technical effects: 1. Laser printing technology can achieve more precise energy control and material deposition, so that the formation of microstructure can be better controlled during the melting and solidification process of the material, resulting in a smaller particle size of chromium particles in the formed contact. The particle size of chromium particles in the contact is smaller than that of chromium particles in the contact processed by the prior art, so that the contact formed by laser printing technology has better insulation ability and better short-circuit breaking ability when applied to the vacuum interrupter; 2. When manufacturing the contact, other parts of the contact structure are combined with the contact at one time to form a whole, without the need to braze the parts with silver-copper solder, which significantly reduces the manufacturing cost; 3. The groove is only opened on the contact cup, that is, the groove is not opened all the way to the contact, which avoids the problem of unqualified flatness due to deformation during parts processing, cleaning and assembly; 4. The contact is formed by cladding the open end surface of the contact cup and the surface of the copper plate using a laser printing process, which can significantly save the amount of contact material compared to the existing technology. In addition, the laser printing process also avoids the quality problem of solder flowing into the chute when the contact is brazed with silver-copper solder. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of an embodiment of the present application; Figure 2 yes Figure 1 A partial enlarged schematic diagram of part A; Figure 3 yes Figure 1 A partial enlarged schematic diagram of part B.

[0023] Explanation of the reference numerals: 1. contact; 2. contact cup; 3. groove; 4. reinforcing rib; 41. connecting column; 42. copper plate. DETAILED DESCRIPTION

[0024] The following is combined with Figure 1-Figure 3 This application is described in further detail.

[0025] The embodiment of the present application discloses a magnetic field contact for a vacuum interrupter.

[0026] refer to Figure 1 A magnetic field contact for a vacuum interrupter comprises a contact cup 2, a contact 1 and a reinforcing rib 4. The contact 1 covers the port of the contact cup 2 and the end face of the reinforcing rib and is fixedly connected to the contact cup 2 and the reinforcing rib. A spiral groove 3 is provided on the circumferential outer wall of the contact cup 2. There are multiple spiral grooves 3. The spiral grooves 3 are spirally provided along the length direction of the contact cup 2. The spiral grooves 3 are only provided on the contact cup 2, that is, the spiral grooves 3 are not fully provided to the contact 1, and adjacent spiral grooves 3 are equidistantly provided along the length direction of the contact cup 2.

[0027] refer to Figure 1 The rotating groove 3 is used to form a longitudinal or transverse magnetic field. When current passes through, the rotating groove 3 will generate a specific magnetic field distribution, which is conducive to the rapid rotation and diffusion of the arc, thereby accelerating the extinction of the arc.

[0028] refer to Figure 1 and Figure 2The reinforcing rib 4 is located inside the contact cup 2 and is fixedly connected to the inner wall of the contact cup 2. In this embodiment, the reinforcing rib 4 is in the shape of a disc, but is not limited to this shape in other embodiments. The outer diameter of the reinforcing rib 4 is the same as the inner diameter of the contact cup 2 at its location. The reinforcing rib 4 is provided with a connecting column 41 and a copper plate 42. The connecting column 41 is located between the reinforcing rib 4 and the copper plate 42. The center line of the connecting column 41 passes through the center of the reinforcing rib 4 and the copper plate 42. One end of the connecting column 41 is fixedly connected to the reinforcing rib 4, and the other end is fixedly connected to the copper plate 42. The side wall of the copper plate 42 facing away from the reinforcing rib 4 is fixedly connected to the contact 1.

[0029] refer to Figure 1 and Figure 2 , the reinforcing rib 4 adopts a conductivity lower than 5×10 6 The reinforcing rib 4 is made of a material with an S / m and magnetic property lower than 1.05, and stainless steel is selected in this embodiment. The contact cup 2 is made of copper with a copper content greater than 99.5% or an alloy material with a copper content greater than 90%.

[0030] The embodiment of the present application also discloses a method for manufacturing a magnetic field contact for a vacuum interrupter.

[0031] The following steps are involved: S1. Clean the contact cup 2 and the reinforcing rib 4.

[0032] S2, placing the reinforcing rib 4 in the contact cup 2; placing the reinforcing rib 4 and the contact cup 2 in an environment filled with reducing gas or in a vacuum environment, and the subsequent laser printing process is performed in an environment filled with reducing gas or in a vacuum environment.

[0033] S3. Modulate the powder of contact 1; the powder of contact 1 meets the electrical performance requirements of the vacuum interrupter, and is made by mixing copper powder and chromium powder in a certain proportion. If necessary, a small amount of other metal powder is added, and the specific proportion is determined according to the electrical performance requirements of the specific vacuum interrupter.

[0034] S4. Perform laser printing and fix the reinforcing rib 4 to the inner wall of the contact cup 2 by cladding. The contact cup 2 is processed with spiral grooves 3 of different numbers and angles along the circumferential side wall according to the requirements of the breaking capacity of the vacuum arc extinguishing chamber; the spiral grooves 3 are opened in a spiral shape along the length direction of the contact cup 2, and the spiral grooves 3 are only opened on the contact cup 2, that is, the spiral grooves 3 are not milled through to the contact 1.

[0035] S5, laser printing is performed on the end surface of the opening end of the contact cup 2 and on the side wall of the copper plate 42 away from the connecting column 41 to form the contact 1 by cladding; S6. Perform mechanical processing on the surface of contact 1 to meet the requirements of the corresponding drawings.

[0036] The embodiments of this specific implementation method are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, all equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A magnetic field contact for a vacuum interrupter, characterized in that: The invention comprises a contact cup (2), a contact (1) and a reinforcing rib (4), wherein the contact (1) covers the port of the contact cup (2) and the end surface of the reinforcing rib and is fixedly connected to the contact cup (2) and the reinforcing rib, a spiral groove (3) is provided on the circumferential outer wall of the contact cup (2), and the spiral groove (3) is used to form a longitudinal or transverse magnetic field, the reinforcing rib (4) is located inside the contact cup (2) and is fixedly connected to the inner wall of the contact cup (2), and the outer diameter of the reinforcing rib (4) is the same as the inner diameter of the contact cup (2) at the position where the reinforcing rib (4) is located.

2. A magnetic field contact for a vacuum interrupter according to claim 1, characterized in that: The spiral groove (3) is opened in a spiral shape along the length direction of the contact cup (2); the spiral groove (3) is opened only on the contact cup (2), that is, the spiral groove (3) is not opened all the way to the contact (1).

3. The magnetic field contact for a vacuum interrupter according to claim 1, characterized in that: The reinforcing rib (4) has a conductivity lower than 5×10 6 The reinforcing rib (4) is made of a material with an S / m and magnetic properties less than 1.

05.

4. The magnetic field contact for a vacuum interrupter according to claim 2, characterized in that: A connecting column (41) and a copper plate (42) are provided on the reinforcing rib (4); the connecting column (41) is located between the reinforcing rib (4) and the copper plate (42); one end of the connecting column (41) is fixedly connected to the reinforcing rib (4); the other end of the connecting column (41) is fixedly connected to the copper plate (42); and the copper plate (42) is fixed to a side wall of the contact (1) close to the inside of the contact cup (2).

5. The magnetic field contact for a vacuum interrupter according to claim 1, characterized in that: The contact cup (2) is made of copper with a copper content greater than 99.5% or an alloy material with a copper content greater than 90%.

6. A method for manufacturing a magnetic field contact for a vacuum interrupter, using the magnetic field contact for a vacuum interrupter as claimed in claim 4, characterized in that: The following steps are involved: S1. Clean the contact cup (2) and the reinforcing rib (4); S2, placing the reinforcing rib (4) in the contact cup (2); S3, modulation contact (1) powder; S4, laser printing is performed to fix the reinforcing rib (4) to the inner wall of the contact cup (2) by means of cladding, and the contact cup (2) is processed with spiral grooves (3) of different numbers and angles along the circumferential side wall according to the requirements of the breaking capacity of the vacuum arc extinguishing chamber; S5, performing laser printing on the end surface of the open end of the contact cup (2) and on the side wall of the copper plate (42) facing away from the connecting column (41), thereby forming the contact (1) by cladding; S6. Mechanically process the surface of the contact (1).

7. The method for manufacturing a magnetic field contact for a vacuum interrupter according to claim 6, characterized in that: All laser printing processes are performed in an environment filled with reducing gas or in a vacuum environment.

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