Spring type vacuum circuit breaker contact structure and circuit breaker
By designing the contact structure of the spring-type vacuum circuit breaker, the problems of electrode bounce and high-temperature arc ablation are solved, the stability and life of the contact are extended, and the breaking capability and reliability of the circuit breaker are improved.
Patent Information
- Application Number
- CN202510718420.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-30
- Publication Date
- 2025-07-11
AI Technical Summary
The existing vacuum circuit breaker contacts have electrode bounce problems and high-temperature arc ablation on the contact surface, resulting in limited life and cannot withstand multiple breaks.
The spring-type vacuum circuit breaker contact structure is adopted, including a symmetrically arranged circuit breaker contact, a conical spiral member, a base and an arc-induced ring, which has elastic expansion and contraction properties. The conical spiral member does not come into contact with the current electrode, forming a flow guide path. The arc-induced ring uses copper-tungsten alloy material to reduce ablation.
Significantly reduce bounce phenomenon, reduce bounce voltage, improve loop stability, extend the service life of the circuit breaker, enhance arc extinguishing capability, and improve the reliability and stability of the circuit breaker.
Smart Images
Figure CN120299945A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of power equipment, and particularly relates to a spring-type vacuum circuit breaker contact structure and a circuit breaker. Background Art
[0002] A circuit breaker (tapered spiral part 1ir tapered spiral part 1uit-br arcing ring 3ak arcing ring 3r) is an important control device in the power system. Its function is to close, carry, and interrupt the current under normal circuit conditions, and be able to carry and interrupt the current under abnormal circuit conditions (such as short-circuit conditions) within a specified time. Among them, the vacuum circuit breaker, as an environmentally friendly circuit breaker structure, has broad application and development prospects. It completes the interruption of the current by extinguishing the arc in the vacuum interrupter. The contact is the most important component in the vacuum interrupter. The improvement of the breaking capacity of the vacuum interrupter depends to a large extent on the principle structure of the contact. At present, the contacts of vacuum interrupters have three typical structural forms: flat contacts; transverse magnetic field contacts (cup-shaped, spiral); longitudinal magnetic field contacts. Among them, the longitudinal magnetic field contact applies a magnetic field along the axial direction of the positive-polarity vacuum arc column, making the arc extinguishing more intense and having a stronger breaking capacity. However, the current design of vacuum circuit breaker contacts still has the following deficiencies: 1. Electrode bounce problem Since the contacts mostly adopt a rigid structure design, bounce is likely to occur due to the relatively high speed when the electrodes close, and then a bounce overvoltage is generated, affecting the stability of the circuit.
[0003] 2. Through-current resistance problem Since it is necessary to strike an arc on the contact surface during the breaking process, the contact surface will become uneven due to ablation by the high-temperature arc. During the closing and through-current process, this uneven surface will have a large contact resistance due to the inability to fit closely, and then problems such as heating and energy loss will occur.
[0004] Therefore, the life of the contacts of the vacuum circuit breaker is relatively limited and cannot withstand a large number of breakings. Summary of the Invention
[0005] The technical problem to be solved by the present invention is that the existing circuit breakers have an electrode bounce problem during contact, and the contact surface will be ablated by the high-temperature arc. The purpose is to provide a spring-type vacuum circuit breaker contact structure and a circuit breaker, which adopt corresponding technical solutions and have the beneficial effects of closing buffering, reducing ablation, and protecting the circuit breaker.
[0006] The present invention is achieved by the following technical solutions: In a first aspect, the present invention provides a spring-type vacuum circuit breaker contact structure, which includes two symmetrically arranged circuit breaker contacts. Each circuit breaker contact includes a conical spiral member. One end of the conical spiral member is connected to a base, and the other end is connected to an arcing ring. The base is connected to a current-carrying electrode inserted into the conical spiral member. The distance between the two arcing rings of the two circuit breaker contacts is less than the distance between the two bases. The conical spiral member has elastic telescopic performance, and the conical spiral member, the base, and the arcing ring all have current-carrying performance.
[0007] In the above technical solution, the two symmetrically arranged circuit breaker contacts. This symmetric structure design helps the spring-type vacuum circuit breaker contact structure maintain force balance on the one hand, avoiding problems such as wear and poor contact of the current-carrying electrode and the arcing ring caused by uneven force. Each circuit breaker contact is composed of a conical spiral member, a base, an arcing ring, and a current-carrying electrode. Among them, the conical spiral member is in a conical spiral shape, with one end fixedly connected to the base and the other end connected to the arcing ring.
[0008] Further, in the present invention, the above-mentioned current-carrying electrode does not contact the conical spiral member.
[0009] Further, in the present invention, the height of the above-mentioned conical spiral member is h1, and the height of the current-carrying electrode is h2, and the two heights satisfy h2 < h1.
[0010] Further, in the present invention, the two heights of h2 and h1 satisfy |h2 - h1| < 1 cm.
[0011] Further, in the present invention, the thickness of the above-mentioned arcing ring is not less than 0.5 cm.
[0012] Further, in the present invention, the end faces of the two arcing rings of the two circuit breaker contacts are parallel to each other.
[0013] Further, in the present invention, the end faces of the two current-carrying electrodes of the two circuit breaker contacts are parallel to each other.
[0014] Further, in the present invention, the material of the above-mentioned arcing ring is configured as a copper-tungsten alloy.
[0015] Further, in the present invention, the centers of the above-mentioned conical spiral member, the base, and the arcing ring are on the same straight line.
[0016] In a second aspect, the present invention also provides a circuit breaker that employs a spring-type vacuum circuit breaker contact structure.
[0017] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The spring - type vacuum circuit breaker contact structure and the circuit breaker of the present invention are provided with a conical spiral member having elastic telescopic performance. When the contacts are closed, the conical spiral member can absorb the kinetic energy at the moment of contact closing through its own elastic deformation, effectively buffering the impact force of the contacts, thus significantly reducing the bouncing phenomenon, reducing the generation of bounce over - voltage, and improving the stability of the circuit.
[0018] 2. The conical spiral member in the form of a conical spring generates a longitudinal magnetic field along the arc column direction during the arc - extinguishing process of opening, promoting the extinction of the opening arc.
[0019] 3. The current - carrying electrode serves as the main contact, and the arcing ring serves as the arcing contact. In the form of separating the main contact from the arcing contact, during the opening process, the main contact breaks first, and then the arcing contact draws the arc. This opening mode reduces the ablation of the main contact by the arc, reduces the additional resistance generated due to surface ablation of the main contact in the closed state, protects the current - carrying electrode, and extends the service life.
[0020] The spring - type vacuum circuit breaker contact structure and the circuit breaker effectively solve the problems existing in the existing contacts, enabling the circuit breaker to withstand more frequent opening operations, improving the reliability and stability of the circuit breaker, extending the overall service life of the circuit breaker, and having high practical value and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other relevant drawings can also be obtained based on these drawings. In the drawings: Figure 1 is a schematic diagram of the spring - type vacuum circuit breaker contact structure according to an embodiment of the present invention; Figure 2 is a schematic diagram of the circuit breaker contact according to an embodiment of the present invention.
[0022] Reference numerals in the drawings and corresponding component names: 1 - conical spiral member, 2 - base, 3 - arcing ring, 4 - current - carrying electrode. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0023] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the embodiments and the drawings. The illustrative embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.
[0024] The following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the scope of protection of the present invention.
[0025] It should be noted that like reference numerals and letters denote like items in the following figures, and thus, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.
[0026] In the description of the embodiments of the present invention, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings or the orientation or positional relationship in which the product of the invention is customarily placed. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 a limitation of the present invention.
[0027] In addition, terms such as "horizontal", "vertical", "hanging" do not mean that the component is required to be absolutely horizontal or hanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.
[0028] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly defined and limited, if terms such as "set", "installed", "connected", "connected to" are used, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.
[0029] Embodiment 1 Combine Figure 2As shown, the contact structure of the spring-type vacuum circuit breaker in this embodiment mainly includes two circuit breaker contacts, which are symmetrically installed when installed in the circuit breaker. The circuit breaker contact includes three parts: a base 2, a conical spiral member 1, and an arcing ring 3 arranged in sequence. The base 2 and the arcing ring 3 are respectively fixedly installed at both ends of the conical spiral member 1. One end of the current-carrying electrode 4 is fixedly connected to the base 2, and the other end of the current-carrying electrode 4 extends into the interior of the conical spiral member 1, and the conical spiral member 1 does not contact the outer wall of the current-carrying electrode 4. The conical spiral member 1 has elastic telescopic properties, and the conical spiral member 1, the base 2, and the arcing ring 3 all have current-carrying properties.
[0030] Furthermore, in combination with Figure 2 As shown, the base 2 is a circular plate, the arcing ring 3 is a circular ring, and the centers of the conical spiral member 1, the base 2, and the arcing ring 3 are on the same straight line. This coaxial design further ensures the symmetry and stability of the contact structure of the spring-type vacuum circuit breaker.
[0031] The base 2, as a basic component for connecting the contact structure of the spring-type vacuum circuit breaker to the external circuit, has a shape adapted to the installation interface of the vacuum interrupter and is firmly installed on the inner wall of the vacuum interrupter by means such as welding or bolt connection. When the two circuit breaker contacts are assembled, the conical spiral member 1 forms a structure layout similar to a flared opening, which is beneficial for the rapid diffusion of the arc during the opening process and enhances the arc extinguishing effect.
[0032] In other embodiments, the conical spiral member 1 can also be made of special metal materials such as stainless steel, beryllium bronze, or nickel-titanium alloy, and is processed by a spiral winding process. Its spiral structure endows the conical spiral member 1 with unique elastic telescopic properties. At the moment when the contact structure of the spring-type vacuum circuit breaker closes, it can undergo elastic deformation like a spring and absorb the kinetic energy generated by the high-speed movement of the contact. At the same time, the conical spiral member 1 has current-carrying ability, enabling the current to conduct smoothly along the spiral path, which not only ensures the stability of the structure but also facilitates the conduction of the current from the base 2 to the arcing ring 3.
[0033] In this embodiment, in combination with Figure 1 and Figure 2As shown, the conical spiral part 1 of the spring-type vacuum circuit breaker contact structure is made of copper-tungsten alloy material, which has good elastic telescopic performance and current-carrying performance. In a specific embodiment, the height h1 of the conical spiral part 1 can be selected as 5 cm, and the height h2 of the current-carrying electrode 4 is 4.2 cm, meeting the requirement of |h2 - h1| < 1 cm. Such a height difference design can not only ensure that the current-carrying electrode 4 has enough space inside the conical spiral part 1 for current conduction, but also enable the conical spiral part 1 to have sufficient elastic deformation space during the closing and opening processes of the contact. At the same time, the end faces of the two arcing rings 3 of the two circuit breaker contacts are parallel to each other, and the end faces of the two current-carrying electrodes 4 of the two circuit breaker contacts are also parallel to each other. This parallel design ensures that the contacts can achieve surface contact when closed, increasing the contact area, reducing the contact resistance, and ensuring the uniformity and stability of current conduction.
[0034] The base 2 is made of copper-tungsten alloy material and has excellent electrical conductivity. The arcing ring 3 is made of copper-tungsten alloy material, and its thickness is set to 0.5 cm or 0.6 cm, with excellent use effects. The two circuit breaker contacts are symmetrically arranged. The end faces of the two arcing rings 3 are parallel to each other, the end faces of the two current-carrying electrodes 4 are also parallel to each other, and the distance between the two arcing rings 3 is less than the distance between the two bases 2, which is convenient for the arcing rings 3 to be butted together. Furthermore, as an important support and current-carrying component of the spring-type vacuum circuit breaker contact structure, the base 2 can also be made of highly conductive metal materials such as pure copper or brass. The base 2 is internally provided with a jack structure matching the current-carrying electrode 4. The shape and dimensional accuracy of the jack ensure that the current-carrying electrode 4 can be firmly inserted and maintain good electrical connection, and then be welded and fixed.
[0035] At the same time, the connection part between the base 2 and the conical spiral part 1 is specially treated with a high-strength welding process to ensure that during the frequent opening and closing processes of the spring-type vacuum circuit breaker contact structure, the two always maintain a firm connection and good electrical conductivity.
[0036] The arcing ring 3 is a key component in the spring-type vacuum circuit breaker contact structure and is made of copper-tungsten alloy material. The combination of the good electrical conductivity of copper and the high melting point and arc erosion resistance characteristics of tungsten in the copper-tungsten alloy enables the arcing ring 3 to maintain stable physical and electrical properties under the action of arc high temperature. The thickness of the arcing ring 3 is not less than 0.5 cm, and its outer surface is finely polished to form a smooth and flat surface to reduce the attachment and erosion of the arc on the surface of the arcing ring 3. The arcing ring 3 is tightly connected to the conical spiral part 1 by welding to ensure that current can be smoothly conducted from the conical spiral part 1 to the arcing ring 3.
[0037] The current-carrying electrode 4 is inserted inside the conical spiral member 1 and does not contact the conical spiral member 1, maintaining a tiny air gap between the two. The purpose of this design is to avoid the generation of additional contact resistance due to contact between the current-carrying electrode 4 and the conical spiral member 1 during current conduction. The current-carrying electrode 4 is made of a highly pure conductive metal material, such as pure copper. The shape of the current-carrying electrode 4 is cylindrical, and its diameter and length are designed according to the internal space of the conical spiral member 1 and the current conduction requirements. One end of the current-carrying electrode 4 is tightly connected to the socket of the base 2 and fixed by welding, and the other end extends to a position close to the arcing ring 3 but does not contact the arcing ring 3.
[0038] In practical applications, when the circuit breaker is closed, the conical spiral member 1 can effectively absorb the impact force generated by the closing of the contact, controlling the bounce amplitude of the contact within a very small range. Compared with the traditional rigid contact structure, the bounce overvoltage is effectively reduced. During the opening process, the arcing ring 3 remains connected at the moment when the current-carrying electrode 4 is disconnected, significantly improving the service life of the contact and the working performance of the circuit breaker. Embodiment 2 This embodiment focuses on studying the performance of the contact structure under different working environments. The spring-type vacuum circuit breaker contact structure is installed in a power equipment with a large temperature variation (-10°C - 50°C) and a high humidity (relative humidity can reach 80%) for testing. The conical spiral member 1 can still maintain stable elastic performance in an environment with a large temperature variation. The materials of the current-carrying electrode 4, the base 2, and the arcing ring 3 are the same as those in Embodiment 1. After a long-term operation test, the spring-type vacuum circuit breaker contact structure can still work normally in a harsh environment. In a low-temperature environment, the elastic performance of the conical spiral member 1 does not show an obvious decrease, and it can still effectively buffer the impact force when the contact is closed, avoiding the bounce phenomenon; in a high-humidity environment, no obvious oxidation, corrosion, or other problems affecting the conductive performance occur in each component of the contact, the contact resistance is stable, and the opening and current-carrying performance of the circuit breaker are good, proving that the spring-type vacuum circuit breaker contact structure has strong environmental adaptability and can meet the requirements of different working environments. Embodiment 3 This embodiment optimizes the contact structure for large current interruption scenarios. On the basis of the original structure, the wire diameter and the number of turns of the conical spiral member 1 are appropriately increased to improve its elastic buffering ability; at the same time, the diameter and thickness of the arcing ring 3 are increased. The thickness of the arcing ring 3 is increased to 2 times that of Embodiment 1 to further enhance the overcurrent capacity. When conducting a high-current (1 kA) breaking test on this contact structure, the conical spiral part 1 can effectively absorb the huge impact force during the contact closing and breaking processes, and the contact bounce amplitude can be almost ignored. After the arcing ring 3 withstands the ablation of high-current arcs, although there is a certain degree of loss on the surface, it can still maintain good shape and electrical conductivity. During the subsequent closing and current-carrying processes, the contact resistance is small and stable, ensuring the reliable operation of the circuit breaker in high-current breaking scenarios and meeting the requirements of the special working conditions for the contact performance of the vacuum circuit breaker.
[0039] Embodiment 4 This embodiment provides a circuit breaker that adopts the spring-type vacuum circuit breaker contact structure in Embodiment 1.
[0040] The spring-type vacuum circuit breaker contact structure and the working principle of the circuit breaker of the present invention are as follows: When the circuit breaker is in the closed state, the spring-type vacuum circuit breaker contact structure is tightly closed, the conical spiral part 1 in the spring-type vacuum circuit breaker contact structure is compressed, and the contact surfaces of the arcing rings 3 and the current-carrying electrodes 4 in the two spring-type vacuum circuit breaker contact structures are tightly attached for current conduction, and the circuit is in the conducting state. During the breaking process of the circuit breaker, as the moving contact (the spring-type vacuum circuit breaker contact structure on the left side) moves horizontally to the left, the upper contact surface of the main current-carrying electrode 4 of the moving contact and the static contact (the spring-type vacuum circuit breaker contact structure on the right side) first separates. Due to the existence of the elastic force of the conical spiral part 1, the end surface of the arcing ring 3 in the spring-type vacuum circuit breaker contact structure still tightly adheres, and the circuit is still conducting.
[0041] As the moving distance of the moving contact gradually increases, the elastic potential energy of the conical spiral part 1 in the moving and static contacts is completely released, and the contact surfaces of the two arcing rings 3 separate, generating an arc. At the moment of arc generation, due to the action of the spiral structure of the conical spiral part 1 in the moving and static contacts, a strong magnetic field in the direction of the cylinder center line is generated, accelerating the diffusion of the arc path and helping the arc to extinguish quickly. After the arc is extinguished, the vacuum insulation strength quickly recovers until the system recovery voltage cannot break through. At this time, the spring-type vacuum circuit breaker contact structure stops moving, and the breaking process ends.
[0042] In the open state of the circuit breaker, the moving and static contacts are separated, and the elastic potential energy of the conical spiral part 1 in the contact structure of the spring-type vacuum circuit breaker is completely released, and the circuit is disconnected. During the closing process of the circuit breaker, with the movement of the moving contact, pre-breakdown occurs on the surfaces of the two arcing rings 3 of the moving and static contacts under the action of the closing voltage, triggering a pre-breakdown arc. With the continuous movement of the moving contact, the surfaces of the arcing rings 3 in the moving and static contacts first come into contact, the pre-breakdown arc extinguishes, and the metal spiral structure, the conical spiral part 1, in the contact structure of the spring-type vacuum circuit breaker begins to convert kinetic energy into elastic potential energy to buffer the closing process of the contacts. The closing process ends until the current-carrying electrode 4 of the main contact makes contact.
[0043] In summary, the present invention provides a contact structure for a spring-type vacuum circuit breaker, which includes two symmetrically arranged circuit breaker contacts. The circuit breaker contact includes a conical spiral part 1. One end of the conical spiral part 1 is connected to a base 2, and the other end of the conical spiral part 1 is connected to an arcing ring 3. The base 2 is connected to a current-carrying electrode 4 inserted into the interior of the conical spiral part 1. The distance between the two arcing rings 3 of the two circuit breaker contacts is less than the distance between the two bases 2. The conical spiral part 1 has elastic telescopic performance, and the conical spiral part 1, the base 2, and the arcing ring 3 all have current-carrying performance. The current-carrying electrode 4 does not contact the conical spiral part 1. The height of the conical spiral part 1 is h1, and the height of the current-carrying electrode 4 is h2, and the two heights satisfy h2 < h1. The two heights of h2 and h1 satisfy |h2 - h1| < 1 cm. The thickness of the arcing ring 3 is not less than 0.5 cm. The end faces of the two arcing rings 3 of the two circuit breaker contacts are parallel to each other. The end faces of the two current-carrying electrodes 4 of the two circuit breaker contacts are parallel to each other. The material of the arcing ring 3 is configured as a copper-tungsten alloy. The centers of the conical spiral part 1, the base 2, and the arcing ring 3 are on the same straight line. The present invention also provides a circuit breaker that uses the contact structure of the spring-type vacuum circuit breaker.
[0044] Therefore, the contact structure of the spring-type vacuum circuit breaker and the circuit breaker of the present invention have the beneficial effects of closing buffering, reducing ablation, and protecting the circuit breaker.
[0045] The specific embodiments described above further elaborate on the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A spring-type vacuum circuit breaker contact structure, characterized in that, It includes two symmetrically arranged circuit breaker contacts. The circuit breaker contacts include a conical spiral member (1). One end of the conical spiral member (1) is connected to a base (2), and the other end of the conical spiral member (1) is connected to an arcing ring (3). The base (2) is connected to a current-carrying electrode (4) inserted into the interior of the conical spiral member (1). The distance between the two arcing rings (3) of the two circuit breaker contacts is less than the distance between the two bases (2). The conical spiral member (1) has elastic telescopic performance, and the conical spiral member (1), the base (2), and the arcing ring (3) all have current-carrying performance.
2. The spring-type vacuum circuit breaker contact structure according to claim 1, characterized in that, The current-carrying electrode (4) does not contact the conical spiral member (1).
3. The spring-type vacuum circuit breaker contact structure according to claim 1, characterized in that, The height of the conical spiral member (1) is h1, and the height of the current-carrying electrode (4) is h2. The two heights satisfy h2 < h1.
4. The spring-type vacuum circuit breaker contact structure according to claim 3, wherein, The two heights of h2 and h1 satisfy |h2 - h1| < 1 cm.
5. The spring-type vacuum circuit breaker contact structure according to claim 1, characterized in that The thickness of the arcing ring (3) is not less than 0.5 cm.
6. The spring-type vacuum circuit breaker contact structure according to claim 1, characterized in that, The end faces of the two arcing rings (3) of the two circuit breaker contacts are parallel to each other.
7. The spring-type vacuum circuit breaker contact structure according to claim 1, characterized in that, The end faces of the two current-carrying electrodes (4) of the two circuit breaker contacts are parallel to each other.
8. The spring-type vacuum circuit breaker contact structure according to claim 1, wherein The material of the arcing ring (3) is configured as a copper-tungsten alloy.
9. The spring-type vacuum circuit breaker contact structure according to claim 1, characterized in that, The centers of the conical spiral member (1), the base (2), and the arcing ring (3) are on the same straight line.
10. A circuit breaker, characterized in that, Adopt the spring-type vacuum circuit breaker contact structure as described in any one of claims 1-9.