Vacuum contact

Abstract

The vacuum contact comprises a static end contact and a moving end contact, the static end contact comprises a first transverse magnetic assembly and a first longitudinal magnetic assembly, the first transverse magnetic assembly comprises a first spiral arm contact piece and a first conducting rod, the first longitudinal magnetic assembly is of a hollow structure, and the first longitudinal magnetic assembly is arranged on the peripheral side of the first conducting rod in a sleeving mode; the first radial arm contact blade is fixed at one end of the first conducting rod and is in contact with the first longitudinal magnetic assembly; the moving end contact comprises a second transverse magnetic assembly and a second longitudinal magnetic assembly, the second transverse magnetic assembly comprises a second radial arm contact blade and a second conducting rod, the second radial arm contact blade is fixed at one end of the second conducting rod and is arranged opposite to the first radial arm contact blade, and the second longitudinal magnetic assembly is of a hollow structure and is fixed on the first radial arm contact blade. The second longitudinal magnetic assembly sleeves the peripheral side of the second conductive rod. The advantages of the two magnetic fields are combined to control movement and diffusion of the vacuum arc, and the breaking capacity of the vacuum contact is improved from the aspect of mechanism.

Description

Technical Field

[0001] This invention relates to the field of vacuum circuit breaker technology, and in particular to a vacuum contact. Background Technology

[0002] Vacuum circuit breakers are key devices used in high-voltage power systems to protect circuits. They can quickly disconnect circuits to prevent damage from overloads or short circuits. In recent years, with the rapid growth of my country's economy, the demand for electricity has increased significantly, and the capacity of generator sets has risen year by year, leading to a corresponding increase in short-circuit current. This necessitates vacuum interrupters with stronger breaking capacity. Currently, improving breaking capacity is mainly achieved by controlling the arc with a magnetic field. During operation, the magnetic field is primarily generated by the contact structure. Vacuum interrupters are mainly classified into two types: transverse magnetic contacts and longitudinal magnetic contacts. Transverse magnetic contacts drive the arc to rotate between poles using a transverse magnetic field, reducing localized ablation of the contact surface. Longitudinal magnetic contacts, on the other hand, generate a longitudinal magnetic field that maintains the arc's diffusion state, reducing arc voltage and arc energy, thereby improving switching efficiency.

[0003] Longitudinal magnetic contacts mainly include coil and cup-shaped types. While coil-shaped contacts can provide a strong longitudinal magnetic field and improve opening and closing capabilities, they have high resistance and generate significant heat, which may cause severe ablation. Cup-shaped contacts provide a weaker longitudinal magnetic field and have weaker arc control capabilities. Transverse magnetic contacts mainly include spiral groove, cup-shaped, and swastika-shaped groove types. Although they can provide a strong transverse magnetic field to drive arc movement, they are unstable in maintaining the arc diffusion pattern, and the arc energy flow density is relatively high, which is unfavorable for arc breaking.

[0004] Current contact structures all use a single magnetic field to control arc propagation, which cannot avoid the problems caused by single magnetic field contacts. For example, longitudinal magnetic contacts have a slow arc propagation speed, and transverse magnetic contacts are not suitable for breaking large currents. Summary of the Invention

[0005] The technical problem this invention aims to solve is that current contact structures all use a single magnetic field to control arc diffusion, which cannot avoid the problems caused by single magnetic field contacts. For example, longitudinal magnetic contacts have slow arc diffusion speed, and transverse magnetic contacts are not suitable for breaking large currents.

[0006] To solve the above-mentioned technical problems, the present invention provides a vacuum contact, comprising: A stationary contact includes a first transverse magnetic assembly and a first longitudinal magnetic assembly. The first transverse magnetic assembly includes a first rotating arm contact piece and a first conductive rod. The first longitudinal magnetic assembly has a hollow structure and is sleeved on the outer periphery of the first conductive rod and sealed to it. The first rotating arm contact piece is fixed to one end of the first conductive rod and contacts the first longitudinal magnetic assembly. The moving end contact includes a second transverse magnetic assembly and a second longitudinal magnetic assembly. The second transverse magnetic assembly includes a second rotating arm contact piece and a second conductive rod. The second rotating arm contact piece is fixed to one end of the second conductive rod and is disposed opposite to the first rotating arm contact piece. The second longitudinal magnetic assembly has a hollow structure and is sleeved on the outer periphery of the second conductive rod. The second conductive rod is configured to move longitudinally relative to the second longitudinal magnetic assembly. When the circuit is closed, the first rotating arm contact plate contacts the second rotating arm contact plate, and there is a gap between the second rotating arm contact plate and the second longitudinal magnetic assembly; When the circuit is opened, the second conductive rod causes the second rotating arm contact piece to separate from the first rotating arm contact piece, and gradually moves to contact the second longitudinal magnetic component.

[0007] Furthermore, the first longitudinal magnetic assembly includes a first fixed conduit, a first double-layer longitudinal magnetic coil, a first iron core, and a first outer ring; The first fixed conduit, the first double-layer longitudinal magnetic coil, the first iron core, and the first outer ring are all sleeved on the outer periphery of the first conductive rod. The first fixed conduit is sealed to the first conductive rod. The two ends of the first double-layer longitudinal magnetic coil are respectively connected to the first fixed conduit and the first outer ring. The first iron core is fixed to the inner wall of the first double-layer longitudinal magnetic coil and nested between the first outer ring and the first fixed conduit. The first outer ring is in contact with the first rotary arm contact piece. The second longitudinal magnetic assembly includes a second fixed conduit, a second double-layer longitudinal magnetic coil, a second iron core, and a second outer ring; The second fixed conduit, the second double-layer longitudinal magnetic coil, the second iron core, and the second outer ring are all sleeved on the outer periphery of the second conductive rod. The second fixed conduit is slidably connected to the second conductive rod. The two ends of the second double-layer longitudinal magnetic coil are respectively connected to the second fixed conduit and the second outer ring. The second iron core is fixed to the inner wall of the second double-layer longitudinal magnetic coil and nested between the second outer ring and the second fixed conduit. The second outer ring is configured to form the gap with the second rotating arm contact piece or to contact the second rotating arm contact piece.

[0008] Furthermore, the structure of the first rotary arm contact piece is the same as that of the second rotary arm contact piece. The first rotary arm contact piece includes a first main contact piece and three first outer contact pieces. The three first outer contact pieces are equidistantly spaced around the axis of the first main contact piece to form a fan blade structure. The outer edge shape of the first outer contact piece is adapted to the inner edge shape of the first outer ring.

[0009] Furthermore, both the first and second rotary arm contact plates are made of CuCr50 material.

[0010] Furthermore, both the first double-layer longitudinal magnetic coil and the second double-layer longitudinal magnetic coil are 2 / 3 turn coils.

[0011] Furthermore, the first double-layer longitudinal magnetic coil, the second double-layer longitudinal magnetic coil, the first conductive rod, the second conductive rod, the first fixed conduit, and the second fixed conduit are all made of oxygen-free copper material.

[0012] Furthermore, the structure of the first iron core is the same as that of the second iron core, and the first iron core has a grid-like structure.

[0013] Furthermore, the diameter of the first iron core gradually decreases in the direction away from the first outer ring.

[0014] Furthermore, both the first and second iron cores are made of pure iron.

[0015] Furthermore, the structure of the first outer ring is the same as that of the second outer ring. The first outer ring includes three ring bodies, which are spaced apart around the axis of the first conductive rod, and there is a gap between adjacent ring bodies.

[0016] Compared with the prior art, the vacuum contact of this invention has the following advantages: In this embodiment of the invention, when in the closed state (zero-loss mode), the first and second rotating arm contact plates are in close contact, and the current is mainly transmitted through the first and second conductive rods, the first and second rotating arm contact plates, and the second rotating arm contact plate. Because there is a gap between the first and second rotating arm contact plates and the second longitudinal magnetic component that generates longitudinal magnetism, they are electrically in a bypass or disconnected state, and the operating current does not pass through the second longitudinal magnetic component, reducing operating heat generation.

[0017] The opening process involves two stages: In the first stage, when the vacuum contact is open, current flows into the first rotating arm contact plate, and the second conductive rod pulls the second rotating arm contact plate open, generating an electric arc in the middle. Under the influence of the second rotating arm contact plate structure, a strong transverse magnetic field is generated between the first and second rotating arm contact plates. Under the influence of the first longitudinal magnetic component, a longitudinal magnetic field is generated between the first and second rotating arm contact plates. These two magnetic fields simultaneously drive the electric arc to move rapidly and maintain its diffusion between the first and second rotating arm contact plates, slowing down contact surface ablation. Second stage: When the vacuum contact reaches the open state, the second rotating arm contact plate contacts the second longitudinal magnetic component. Current flows through the longitudinal magnetic component, and a longitudinal magnetic field is further generated in the gap between the first rotating arm contact plate and the second rotating arm contact plate. This longitudinal magnetic field is superimposed on the longitudinal magnetic field generated by the first longitudinal magnetic component, making the longitudinal magnetic field stronger and more effective in maintaining and spreading the arc, thus greatly improving the breaking capacity.

[0018] This embodiment combines the advantages of two magnetic fields to control the movement and diffusion of the vacuum arc. Through the synergistic effect of first driving with transverse magnetic field and then spreading with longitudinal magnetic field, the dominant transverse magnetic field is used to drive the arc to move outward rapidly. Then, upon contact with the second longitudinal magnetic component, the longitudinal magnetic field becomes dominant, controlling the arc to maintain its diffusion pattern. This achieves rapid arc movement and sustained diffusion, thereby improving the breaking capability of the vacuum contact from a mechanistic perspective. Attached Figure Description

[0019] The present application will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, those skilled in the art will appreciate that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be construed as limiting the scope of the present application. Furthermore, unless specifically indicated, the drawings are intended only to conceptually represent the composition or structure of the described objects and may contain exaggerated representations, and the drawings are not necessarily drawn to scale.

[0020] Figure 1 This is a schematic diagram of the closed state of the vacuum contact provided in an embodiment of the present invention; Figure 2 This is a top view of the closed state of the vacuum contact provided in an embodiment of the present invention; Figure 3 This is provided along with the embodiments of the present invention. Figure 2 A cross-sectional view along the AA direction; Figure 4 This is a schematic diagram of the open state of the vacuum contact provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the stationary contact provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the moving end contact provided in an embodiment of the present invention; In the figure, 1 is the stationary contact; 11 is the first transverse magnetic assembly; 111 is the first rotating arm contact piece; 1111 is the first main contact piece; 1112 is the first outer contact piece; 112 is the first conductive rod; 12 is the first longitudinal magnetic assembly; 121 is the first fixed guide tube; 122 is the first double-layer longitudinal magnetic coil; 123 is the first iron core; and 124 is the first outer ring. 2. Moving end contact; 21. Second transverse magnetic assembly; 211. Second rotating arm contact piece; 212. Second conductive rod; 22. Second longitudinal magnetic assembly; 221. Second fixed guide tube; 222. Second double-layer longitudinal magnetic coil; 223. Second iron core; 224. Second outer ring. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0022] It should be noted that the terms "first," "second," etc., are used only for the convenience of describing this technical solution and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0023] like Figures 1 to 4 As shown, the present invention provides a vacuum contact, including a stationary contact 1 and a moving contact 2; wherein: The stationary contact 1 includes a first transverse magnetic assembly 11 and a first longitudinal magnetic assembly 12. The first transverse magnetic assembly 11 includes a first rotating arm contact piece 111 and a first conductive rod 112. The first longitudinal magnetic assembly 12 has a hollow structure. The first longitudinal magnetic assembly 12 is sleeved on the outer periphery of the first conductive rod 112 and is sealed to the first conductive rod 112. The first rotating arm contact piece 111 is fixed to one end of the first conductive rod 112 and contacts the first longitudinal magnetic assembly 12. The moving contact 2 includes a second transverse magnetic assembly 21 and a second longitudinal magnetic assembly 22. The second transverse magnetic assembly 21 includes a second rotating arm contact piece 211 and a second conductive rod 212. The second rotating arm contact piece 211 is fixed to one end of the second conductive rod 212 and is disposed opposite to the first rotating arm contact piece 111. The second longitudinal magnetic assembly 22 is a hollow structure and is sleeved on the outer periphery of the second conductive rod 212. The second conductive rod 212 is configured to move longitudinally relative to the second longitudinal magnetic assembly 22. When the circuit is closed, the first rotating arm contact piece 111 contacts the second rotating arm contact piece 211, and there is a gap between the second rotating arm contact piece 211 and the second longitudinal magnetic assembly 22. When the circuit is opened, the second conductive rod 212 drives the second rotating arm contact piece 211 to separate from the first rotating arm contact piece 111 and gradually moves to contact the second longitudinal magnetic assembly 22.

[0024] Based on the above structure, when in the closed state (zero-loss mode), the first rotating arm contact piece 111 and the second rotating arm contact piece 211 are in close contact, and the current is transmitted through the first conductive rod 112, the second conductive rod 212, the first rotating arm contact piece 111, and the second rotating arm contact piece 211. Because there is a gap between the first rotating arm contact piece 111 and the second rotating arm contact piece 211 and the second longitudinal magnetic component 22 that generates longitudinal magnetism, they are electrically in a bypass or disconnected state, and the operating current does not pass through the second longitudinal magnetic component 22, reducing operating heat generation.

[0025] During the opening process, there are two stages: In the first stage, when the vacuum contact is in the open state, current flows in from the first rotating arm contact piece 111, and the second conductive rod 212 drives the second rotating arm contact piece 211 to open, at which point an electric arc is generated in the middle. Under the influence of the second rotating arm contact piece 211, a strong transverse magnetic field is generated in the gap between the first and second rotating arm contact pieces 111. Under the influence of the first longitudinal magnetic component 12, a longitudinal magnetic field is generated in the gap between the first and second rotating arm contact pieces 111. Both magnetic fields simultaneously drive the electric arc to move rapidly and maintain diffusion between the first and second rotating arm contact pieces 111, slowing down contact surface ablation. Second stage: When the vacuum contact reaches the open state, the second rotating arm contact piece 211 contacts the second longitudinal magnetic component 22. Current flows through the longitudinal magnetic component, and a longitudinal magnetic field is further generated in the gap between the first rotating arm contact piece 111 and the second rotating arm contact piece 211. This longitudinal magnetic field is superimposed on the longitudinal magnetic field generated by the first longitudinal magnetic component 12, resulting in a stronger longitudinal magnetic field and a more effective arc maintenance and diffusion effect, thus greatly improving the breaking capacity.

[0026] This embodiment combines the advantages of two magnetic fields to control the movement and diffusion of the vacuum arc. Through the synergistic effect of first driving with transverse magnetic field and then spreading with longitudinal magnetic field, the dominant transverse magnetic field is used to drive the arc to move outward rapidly. Then, upon contact with the second longitudinal magnetic component 22, the longitudinal magnetic field becomes dominant, controlling the arc to maintain its diffusion pattern. This achieves rapid movement and sustained diffusion of the arc, thereby improving the breaking capability of the vacuum contact from a mechanistic perspective.

[0027] Understandably, in this embodiment, the first conductive rod 112 of the stationary contact 1 fixes the first rotating arm contact piece 111 to ensure stable current flow in the circuit. In the event of a fault, the second conductive rod 212 pulls the second rotating arm contact piece 211 apart from the first rotating arm contact piece 111, and an electric arc is generated between the first rotating arm contact piece 111 and the second rotating arm contact piece 211, resulting in a strong transverse magnetic field in the gap between them, driving the electric arc to move outward rapidly.

[0028] like Figure 3 , Figure 5 and Figure 6As shown, the first longitudinal magnetic assembly 12 includes a first fixed conduit 121, a first double-layer longitudinal magnetic coil 122, a first iron core 123, and a first outer ring 124. The first fixed conduit 121, the first double-layer longitudinal magnetic coil 122, the first iron core 123, and the first outer ring 124 are all sleeved on the outer periphery of the first conductive rod 112. The first fixed conduit 121 is sealed to the first conductive rod 112. The two ends of the first double-layer longitudinal magnetic coil 122 are respectively connected to the first fixed conduit 121 and the first outer ring 124, serving as the first current flow path. A region is formed to generate an initial longitudinal magnetic field to control arc diffusion; the first rotating arm contact piece 111 is connected to the first conductive rod 112, serving as the second region of the first current flow path; the second rotating arm contact piece 211 is connected to the second conductive rod 212, serving as the third region of the first current flow path; the first iron core 123 is fixed to the inner wall of the first double-layer longitudinal magnetic coil 122 and nested between the first outer ring 124 and the first fixed conduit 121 to enhance the longitudinal magnetic field and reduce eddy currents; the first outer ring 124 is in contact with the first rotating arm contact piece 111.

[0029] The second longitudinal magnetic assembly 22 includes a second fixed conduit 221, a second double-layer longitudinal magnetic coil 222, a second iron core 223, and a second outer ring 224. The second fixed conduit 221, the second double-layer longitudinal magnetic coil 222, the second iron core 223, and the second outer ring 224 are all sleeved on the outer periphery of the second conductive rod 212. The second fixed conduit 221 is slidably connected to the second conductive rod 212, and the second conductive rod 212 and the second fixed conduit 221 move during opening and closing of the circuit. The two ends of the second double-layer longitudinal magnetic coil 222... The second iron core 223 is connected to the second fixed conduit 221 and the second outer ring 224 respectively, so that when the second rotating arm contact piece 211 overlaps with the second outer ring 224, it serves as the first region of the second current flow path; the second iron core 223 is fixed to the inner wall of the second double-layer longitudinal magnetic coil 222 and nested between the second outer ring 224 and the second fixed conduit 221 to enhance the longitudinal magnetic field and reduce eddy currents. The second outer ring 224 is configured to form a gap with the second rotating arm contact piece 211 or to contact the second rotating arm contact piece 211.

[0030] Understandably, the first region, the second region, and the third region of the first current flow path in this embodiment constitute the regions of the first current flow path.

[0031] Furthermore, in this embodiment, the first outer ring 124, the first rotating arm contact piece 111, and the first double-layer longitudinal magnetic coil 122 are connected to form the second region of the second current flow path. When the second outer ring 224, the second rotating arm contact piece 211, and the second double-layer longitudinal magnetic coil 222 are connected, they form the third region of the second current flow path. In this embodiment, the first region, the second region, and the third region of the second current flow path constitute the region of the second current flow path.

[0032] When the vacuum contact is in normal operation, the first rotating arm contact piece 111 and the second rotating arm contact piece 211 are in close contact, forming a current path. When a short circuit fault occurs in the circuit, the vacuum contact begins to break, and the second rotating arm contact piece 211 approaches the second outer ring 224, generating a vacuum arc. At this time, the gap between the first rotating arm contact piece 111 and the second rotating arm contact piece 211 mainly drives the arc movement with a transverse magnetic field. When the second rotating arm contact piece 211 contacts the second outer ring 224, the current flows through the second rotating arm contact piece 211 and through the second double-layer longitudinal magnetic coil 222, and the current flows through the second iron core 223, generating a longitudinal magnetic field in the gap between the first rotating arm contact piece 111 and the second rotating arm contact piece 211 to reduce eddy current losses. At this time, the gap between the first rotating arm contact piece 111 and the second rotating arm contact piece 211 has two magnetic fields (i.e., a longitudinal magnetic field and a transverse magnetic field) working together to drive the arc movement and maintain arc diffusion.

[0033] Furthermore, the structure of the first rotating arm contact piece 111 is the same as that of the second rotating arm contact piece 211. The first rotating arm contact piece 111 includes a first main contact piece 1111 and three first outer contact pieces 1112. The three first outer contact pieces 1112 are equidistantly spaced around the axis of the first main contact piece 1111 to form a fan blade structure. The outer edge shape of the first outer contact piece 1112 is adapted to the inner edge shape of the first outer ring 124.

[0034] Understandably, in this embodiment, the first rotating arm contact piece 111 is the inner structure of the stationary contact 1, consisting of three extending and rotating three-arm-shaped current guiding paths (i.e., three first outer contact pieces 1112 and a first main contact piece 1111). The first main contact piece 1111 is connected to the first conductive rod 112. Similarly, the second rotating arm contact piece 211 includes a second main contact piece and three second outer contact pieces. The three second outer contact pieces are equidistantly spaced around the axis of the second main contact piece to form a fan-shaped structure. The outer edge shape of the second outer contact piece is adapted to the inner edge shape of the second outer ring 224. The second main contact piece is connected to the second conductive rod 212. When the circuit is broken, the current flows through the three-arm-shaped current guiding path to generate a transverse magnetic field, driving the central arc to move outward. In the initial position of the circuit breaker opening, there is a preset gap between the second rotating arm contact piece 211 and the second outer ring 224 of the moving contact 2. The two will only physically overlap after the second conductive rod 212 moves downward beyond a certain stroke.

[0035] It should be noted that the second rotating arm contact piece 211 is connected to the second conductive rod 212. When the contact is working normally, the first rotating arm contact piece 111 and the second rotating arm contact piece 211 are in close contact, and the working current flows normally through the contact. When a circuit fault occurs and the contact is disconnected, the second rotating arm contact piece 211 moves backward, generating a vacuum arc between the electrodes. Under the influence of the fan-blade structure of the first rotating arm contact piece 111 and the second rotating arm contact piece 211, a transverse magnetic field is generated, driving the arc to move rapidly and slowing down erosion.

[0036] Understandably, the three first outer contacts 1112 of the first rotary arm contact 111 and the three second outer contacts of the second rotary arm contact 211 form the first region for arc diffusion; the region between the first rotary arm contact 111, the first outer ring 124 and the first double-layer longitudinal magnetic coil 122, and the region between the second rotary arm contact 211, the second outer ring 224 and the second double-layer longitudinal magnetic coil 222 form the second region for arc diffusion.

[0037] Furthermore, both the first rotary arm contact piece 111 and the second rotary arm contact piece 211 are made of CuCr50 material, so that the first rotary arm contact piece 111 and the second rotary arm contact piece 211 have low contact resistance characteristics, reduce energy loss and temperature rise, and at the same time, they can withstand arc impact without failure when short-circuited or interrupted by large current, and reduce contact erosion and wear, thus reducing maintenance frequency.

[0038] Furthermore, both the first double-layer longitudinal magnetic coil 122 and the second double-layer longitudinal magnetic coil 222 are 2 / 3 turn coils.

[0039] Understandably, the first double-layer longitudinal magnetic coil 122 is the outer structure of the stationary contact 1, consisting of a double-layer coil structure formed by three current-conducting paths that each wind around the circumference 2 / 3 of the way. Similarly, the second double-layer longitudinal magnetic coil 222 is the outer structure of the moving contact 2, consisting of a double-layer coil structure formed by three current-conducting paths that each wind around the circumference 2 / 3 of the way. The first double-layer longitudinal magnetic coil 122 and the second double-layer longitudinal magnetic coil 222 are respectively fixed on the first fixed conduit 121 and the second fixed conduit 221. After a certain period of interruption, the current flows through the three current-conducting paths, generating a longitudinal magnetic field between the stationary contact 1 and the moving contact 2, thus maintaining the arc diffusion.

[0040] When the second rotating arm contact piece 211 and the first rotating arm contact piece 111 are separated and come into contact with the second double-layer longitudinal magnetic coil 222, the current flows through three guiding paths. Each guiding path turns 2 / 3 of a turn and then flows into a low potential through the second fixed conduit 221, generating a strong longitudinal magnetic field between the second rotating arm contact piece 211 and the first rotating arm contact piece 111, maintaining the arc in a diffused state.

[0041] Furthermore, the first double-layer longitudinal magnetic coil 122, the second double-layer longitudinal magnetic coil 222, the first conductive rod 112, the second conductive rod 212, the first fixed conduit 121, and the second fixed conduit 221 are all made of oxygen-free copper material.

[0042] The structure described in this embodiment is made of oxygen-free copper material, which can reduce resistance loss, improve heat conduction and heat dissipation, and enhance resistance to arc erosion, thereby ensuring stable and safe operation of the contacts under frequent operation or fault current.

[0043] Furthermore, the structure of the first iron core 123 is the same as that of the second iron core 223, and the first iron core 123 has a grid-like structure.

[0044] In this embodiment, the grid-shaped first iron core 123 is nested between the first outer ring 124 and the first fixed conduit 121. When current flows from the first rotating arm contact piece 111 through the first iron core 123, it can confine the originally divergent magnetic field into a certain space, enhancing the magnetic induction intensity in the gap between the second rotating arm contact piece 211 and the first rotating arm contact piece 111, thereby improving the control effect of the magnetic field on the electric arc. The grid-shaped structure of this embodiment can also change the eddy current distribution in the first iron core 123, reducing the influence of the remaining longitudinal magnetic field. Similarly, the second iron core 223 can also confine the originally divergent magnetic field into a certain space, enhancing the magnetic induction intensity in the gap between the second rotating arm contact piece 211 and the first rotating arm contact piece 111.

[0045] Furthermore, the diameter of the first iron core 123 gradually decreases in the direction away from the first outer ring 124. By reducing the diameter away from the outer ring end, this embodiment can increase the magnetic flux density in this region, thereby forming a stronger longitudinal magnetic field near the gap between the second rotating arm contact piece 211 and the first rotating arm contact piece 111, thus better controlling the electric arc.

[0046] Furthermore, the first iron core 123 and the second iron core 223 are made of pure iron so that when they are combined with the first double-layer longitudinal magnetic coil 122 and the second double-layer longitudinal magnetic coil 222 respectively, they form a low magnetic resistance path, so that the magnetic lines of force generated by the coil can effectively pass through the gap between the second rotating arm contact piece 211 and the first rotating arm contact piece 111 to generate the required longitudinal magnetic field.

[0047] Furthermore, the structure of the first outer ring 124 is the same as that of the second outer ring 224. The first outer ring 124 includes three ring bodies, which are spaced apart around the axis of the first conductive rod 112, and there is a gap between adjacent two ring bodies. It can be understood that the first outer ring 124 and the second outer ring 224 in this embodiment are hollow ring structures, and have three tangentially opened slots to serve as a further extension and diffusion path of the vacuum arc.

[0048] Understandably, in order to increase the current flow and diffusion area on the arc surface, the three-arm angle and central support circle area of ​​the second rotating arm contact piece 211 and the first rotating arm contact piece 111 can be increased, and the diameters of the first outer ring 124 and the second outer ring 224 can be increased to exceed the diameters of the first double-layer longitudinal magnetic coil 122 and the second double-layer longitudinal magnetic coil 222 by a certain length, so as to improve the current flow and diffusion geometry.

[0049] The work process is as follows: (1) Normal closing and current-carrying state (zero-loss mode): The first rotating arm contact piece 111 and the second rotating arm contact piece 211 are in close contact. The current is mainly transmitted through the low-impedance first conductive rod 112, the first rotating arm contact piece 111, the second rotating arm contact piece 211, and the second conductive rod 212. Since the circuit between the second rotating arm contact piece 211 and the second outer ring 224 that generates longitudinal magnetism is electrically bypassed or disconnected, the operating current does not pass through the high-impedance second double-layer longitudinal magnet coil 222, which significantly reduces the heat generation during operation.

[0050] (2) First stage of circuit breaking: When the stationary contact 1 and the moving contact 2 just separate (at time t0-t1), the second rotating arm contact piece 211 and the second outer ring 224 have not yet made contact. At this time, the current only flows through the first conductive rod 112, the first rotating arm contact piece 111, the second rotating arm contact piece 211 and the second conductive rod 212. The gap between the first rotating arm contact piece 111 and the second rotating arm contact piece 211 generates a high-intensity rotating transverse magnetic field (TMF) and does not generate a longitudinal magnetic field. At this time, the powerful transverse magnetic field drives the newly generated arc root to rotate at high speed and move outward centrifugally, effectively preventing the anode spot from accumulating in the early stage of arc initiation. The centrifugal force is used to push the arc to the edge of the contact.

[0051] (3) Second stage of circuit breaking: When the second conductive rod 212 moves to the preset stroke (at time t1), the edge of the second rotating arm contact piece 211 physically touches the second outer ring 224. At this time, the mechanical switch closes, and the current is diverted to the second outer ring 224, and then flows into the second double-layer longitudinal magnetic coil 222. The second double-layer longitudinal magnetic coil 222 is instantly activated, generating a strong longitudinal magnetic field superimposed on the original magnetic field. At this time, the arc has been pushed to the periphery by the transverse magnetic field of the first stage, and just enters the control range of the second double-layer longitudinal magnetic coil 222. The second iron core 223 binds the longitudinal magnetic field in a certain space, like a magnetic cage, converting the divergent arc into a diffused state, preventing the arc from flying out of the contact, until the current crosses zero and the arc is extinguished.

[0052] In summary, the embodiments of the present invention provide a vacuum contact that combines the advantages of two magnetic fields to control the movement and diffusion of a vacuum arc. Through the synergistic effect of first transverse magnetic drive, then longitudinal magnetic diffusion, and dual current diffusion, the dominant transverse magnetic field is first used to drive the arc to move rapidly outward; then, upon contact with the second longitudinal magnetic component 22, the longitudinal magnetic field becomes dominant, controlling the arc to maintain its diffusion pattern. This achieves rapid arc movement and sustained diffusion, thereby improving the breaking capability of the vacuum contact from a mechanistic perspective.

[0053] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A vacuum contact, characterized in that, include: A stationary contact includes a first transverse magnetic assembly and a first longitudinal magnetic assembly. The first transverse magnetic assembly includes a first rotating arm contact piece and a first conductive rod. The first longitudinal magnetic assembly has a hollow structure and is sleeved on the outer periphery of the first conductive rod and sealed to it. The first rotating arm contact piece is fixed to one end of the first conductive rod and contacts the first longitudinal magnetic assembly. The moving end contact includes a second transverse magnetic assembly and a second longitudinal magnetic assembly. The second transverse magnetic assembly includes a second rotating arm contact piece and a second conductive rod. The second rotating arm contact piece is fixed to one end of the second conductive rod and is disposed opposite to the first rotating arm contact piece. The second longitudinal magnetic assembly has a hollow structure and is sleeved on the outer periphery of the second conductive rod. The second conductive rod is configured to move longitudinally relative to the second longitudinal magnetic assembly. When the circuit is closed, the first rotating arm contact plate contacts the second rotating arm contact plate, and there is a gap between the second rotating arm contact plate and the second longitudinal magnetic assembly; When the circuit is opened, the second conductive rod causes the second rotating arm contact piece to separate from the first rotating arm contact piece, and gradually moves to contact the second longitudinal magnetic component.

2. The vacuum contact according to claim 1, characterized in that, The first longitudinal magnetic assembly includes a first fixed conduit, a first double-layer longitudinal magnetic coil, a first iron core, and a first outer ring; The first fixed conduit, the first double-layer longitudinal magnetic coil, the first iron core, and the first outer ring are all sleeved on the outer periphery of the first conductive rod. The first fixed conduit is sealed to the first conductive rod. The two ends of the first double-layer longitudinal magnetic coil are respectively connected to the first fixed conduit and the first outer ring. The first iron core is fixed to the inner wall of the first double-layer longitudinal magnetic coil and nested between the first outer ring and the first fixed conduit. The first outer ring is in contact with the first rotary arm contact piece. The second longitudinal magnetic assembly includes a second fixed conduit, a second double-layer longitudinal magnetic coil, a second iron core, and a second outer ring; The second fixed conduit, the second double-layer longitudinal magnetic coil, the second iron core, and the second outer ring are all sleeved on the outer periphery of the second conductive rod. The second fixed conduit is slidably connected to the second conductive rod. The two ends of the second double-layer longitudinal magnetic coil are respectively connected to the second fixed conduit and the second outer ring. The second iron core is fixed to the inner wall of the second double-layer longitudinal magnetic coil and nested between the second outer ring and the second fixed conduit. The second outer ring is configured to form the gap with the second rotating arm contact piece or to contact the second rotating arm contact piece.

3. The vacuum contact according to claim 2, characterized in that, The structure of the first rotating arm contact piece is the same as that of the second rotating arm contact piece. The first rotating arm contact piece includes a first main contact piece and three first outer contact pieces. The three first outer contact pieces are equidistantly spaced around the axis of the first main contact piece to form a fan blade structure. The outer edge shape of the first outer contact piece is adapted to the inner edge shape of the first outer ring.

4. The vacuum contact according to claim 2 or 3, characterized in that, Both the first and second rotary arm contact plates are made of CuCr50 material.

5. The vacuum contact according to claim 2, characterized in that, Both the first double-layer longitudinal magnetic coil and the second double-layer longitudinal magnetic coil are 2 / 3 turn coils.

6. The vacuum contact according to claim 2 or 5, characterized in that, The first double-layer longitudinal magnetic coil, the second double-layer longitudinal magnetic coil, the first conductive rod, the second conductive rod, the first fixed conduit, and the second fixed conduit are all made of oxygen-free copper material.

7. The vacuum contact according to claim 2, characterized in that, The structure of the first iron core is the same as that of the second iron core, and the first iron core has a grid-like structure.

8. The vacuum contact according to claim 7, characterized in that, The diameter of the first iron core gradually decreases in the direction away from the first outer ring.

9. The vacuum contact according to claim 2 or 7, characterized in that, The first iron core and the second iron core are made of pure iron.

10. The vacuum contact according to claim 2, characterized in that, The structure of the first outer ring is the same as that of the second outer ring. The first outer ring includes three ring bodies, which are spaced apart around the axis of the first conductive rod, and there is a gap between adjacent ring bodies.

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