A magnetic spinning arc electrode and a plasma generator

Abstract

This utility model relates to a magnetic swirling arc electrode and a plasma generator. The magnetic swirling arc electrode includes an electrode base, a first electrode, a second electrode, a magnetic device, and a swirling ring. The electrode base has a working gas flow channel. The first and second electrodes are insulated from each other and are disposed on the electrode base. The second electrode is axially hollow to form an arc channel and is sleeved outside the first electrode. The magnetic device is disposed on the second electrode to generate an axial magnetic field within the arc channel. The swirling ring is disposed between the working gas flow channel and the arc channel, which are connected by multiple vent holes on the circumferential direction of the swirling ring. The centerline of the vent holes is inclined relative to the axis of the swirling ring and does not pass through the axis of the swirling ring. This magnetic swirling arc electrode can make the generated plasma distribution more uniform, improving the stability and uniformity of the plasma. The magnetic device can increase the arc operating voltage within the arc channel, reduce the operating current at the same power, and improve electrode life.

Description

Technical Field

[0001] This utility model relates to the field of plasma generation equipment technology, and in particular to a magnetic spiral arc electrode and a plasma generator. Background Technology

[0002] Compared with traditional oil gun ignition, plasma ignition has advantages such as being environmentally friendly, efficient, highly automated, and more economical. Therefore, plasma ignition has been widely used in fields such as coupling ignition, waste gas treatment, material treatment, and surface modification.

[0003] The plasma generator is one of the core components of a plasma ignition device. Currently, existing low-power plasma generators have short electrode lifespans and the stability and uniformity of the generated plasma are not ideal. Utility Model Content

[0004] The first objective of this invention is to provide a magnetic spiral arc electrode to extend its service life and improve the stability and uniformity of the generated plasma.

[0005] The second objective of this invention is to provide a plasma generator employing the aforementioned magnetic spiral arc electrode.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A magnetic spiral arc electrode, characterized in that it comprises:

[0008] An electrode base, wherein the electrode base is provided with a working gas flow channel;

[0009] The first electrode is disposed on the electrode base;

[0010] The second electrode is disposed on the electrode base insulated from the first electrode. The second electrode is axially hollow to form an arc channel and is sleeved on the outside of the first electrode.

[0011] A magnetic device is disposed on the second electrode, the magnetic device being used to generate an axial magnetic field within the arc channel;

[0012] A swirl ring is disposed between the working gas flow channel and the electric arc channel. The swirl ring has multiple vent holes evenly distributed around its circumference. The working gas flow channel and the electric arc channel are connected through the vent holes. The center line of the vent holes is inclined relative to the axis of the swirl ring and does not pass through the axis of the swirl ring.

[0013] In one embodiment of this application, the magnetic device is a ring-shaped permanent magnet, which is sleeved outside the second electrode or embedded inside the second electrode.

[0014] In one embodiment of this application, the end of the first electrode away from the electrode base is a first arc-starting structure. The first arc-starting structure includes a columnar outer peripheral surface, a first conical surface, and an electrode end face connected in sequence from near to far from the electrode base. The first conical surface gradually tapers from the end connected to the columnar outer peripheral surface.

[0015] In one embodiment of this application, the inner wall surface of the arc channel near the electrode base is a second arc-starting structure. The second arc-starting structure is sleeved outside the first arc-starting structure. The second arc-starting structure includes a first columnar inner circumferential surface, a second conical surface, and a second columnar inner circumferential surface connected in sequence from near to far from the electrode base. The second conical surface gradually tapers from the end connected to the first columnar inner circumferential surface.

[0016] In one embodiment of this application, the inner wall surface of the arc channel further includes a third conical surface, a third columnar inner circumferential surface, a fourth conical surface, and a fourth columnar inner circumferential surface, which are connected sequentially from the nearest to the farthest end of the second columnar inner circumferential surface away from the second conical surface, according to their distance from the electrode base. The third conical surface gradually narrows from the end connected to the second columnar inner circumferential surface, and the fourth conical surface gradually widens from the end connected to the third columnar inner circumferential surface.

[0017] In one embodiment of this application, the second electrode includes an arc-starting electrode and an output electrode coaxially connected. The inner cavity of the arc-starting electrode communicates with the inner cavity of the output electrode to form the arc channel. The inner wall surface of the arc-starting electrode at the end away from the output electrode is the second arc-starting structure. The magnetic device is disposed on the arc-starting electrode and / or the output electrode. The inner wall surface of the arc-starting electrode is composed of the first columnar inner peripheral surface, the second conical surface, and the second columnar inner peripheral surface. The inner wall surface of the output electrode is composed of the third conical surface, the third columnar inner peripheral surface, the fourth conical surface, and the fourth columnar inner peripheral surface.

[0018] In one embodiment of this application, the arc-starting electrode is threadedly connected to the output electrode.

[0019] In one embodiment of this application, the arc-starting electrode is provided with the magnetic device, and the magnetic device is sleeved on the outer wall surface of the arc-starting electrode at a position corresponding to the inner circumferential surface of the second columnar shape.

[0020] In one embodiment of this application, the output electrode is provided with the magnetic device, and the magnetic device is sleeved on the outer wall surface of the output electrode corresponding to the fourth columnar inner circumferential surface.

[0021] A plasma generator comprising a magnetic spiral arc electrode as described in any of the above claims.

[0022] As can be seen from the above technical solution, this utility model discloses a magnetic swirling arc electrode, which includes an electrode base, a first electrode, a second electrode, a magnetic device, and a swirling ring. The electrode base is provided with a working gas flow channel; the first electrode is disposed on the electrode base; the second electrode is disposed on the electrode base insulated from the first electrode, and has an axially hollow interior forming an arc channel, and is sleeved outside the first electrode; the magnetic device is disposed on the second electrode, and is used to form an axial magnetic field within the arc channel; the swirling ring is disposed between the working gas flow channel and the arc channel, and the swirling ring has multiple vent holes evenly distributed circumferentially. The working gas flow channel and the arc channel are connected through the vent holes, and the centerline of the vent holes does not pass through the axis of the swirling ring.

[0023] In application, one of the first and second electrodes is connected to the positive terminal of the power supply, and the other to the negative terminal, creating a strong electric field between them. The working gas enters the arc channel through the working gas flow channel and the swirling ring. Due to the inclined arrangement of the vent holes, the working gas forms a rotating gas flow field, which makes the distribution of the working gas within the arc channel more uniform and also makes the distribution of the subsequently generated plasma more uniform, thereby improving the stability and uniformity of the generated plasma. Simultaneously, the magnetic device at the second electrode can increase the arc operating voltage within the arc channel and reduce the operating current at the same power, thus extending the electrode life. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 An axial cross-sectional view of the magnetic spiral arc electrode provided in an embodiment of this utility model;

[0026] Figure 2 An axial cross-sectional view of the second electrode of a magnetic spiral arc electrode provided in one embodiment of the present invention;

[0027] Figure 3 An axial cross-sectional view of the second electrode of the magnetic spiral arc electrode provided in another embodiment of the present invention;

[0028] Figure 4 An axial cross-sectional view of the second electrode of the magnetic spiral arc electrode provided in another embodiment of the present invention.

[0029] In the picture:

[0030] 100 is the electrode base; 101 is the working gas flow channel;

[0031] 200 is the first electrode; 201 is the cylindrical outer peripheral surface; 202 is the first conical surface; 203 is the electrode end face;

[0032] 300 is the second electrode; 301 is the arc channel; 302 is the first cylindrical inner circumferential surface; 303 is the second conical surface; 304 is the second cylindrical inner circumferential surface; 305 is the third conical surface; 306 is the third cylindrical inner circumferential surface; 307 is the fourth conical surface; 308 is the fourth cylindrical inner circumferential surface; 310 is the arc-starting electrode; 320 is the output electrode.

[0033] 400 is a swirl ring;

[0034] 500 is a magnetic device; 501 is the first permanent magnet; 502 is the second permanent magnet. Detailed Implementation

[0035] One of the core features of this invention is to provide a magnetic spiral arc electrode, the structural design of which can extend its service life and improve the stability and uniformity of the generated plasma.

[0036] Another core aspect of this invention is to provide a plasma generator employing the aforementioned magnetic spiral arc electrode.

[0037] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0038] Please see Figure 1 and Figure 2 .

[0039] This utility model discloses a magnetic spiral arc electrode, which includes an electrode base 100, a first electrode 200, a second electrode 300, a magnetic device 500, and a swirl ring 400.

[0040] The electrode base 100 is provided with a working gas channel 101, which is used to deliver working gas to the arc channel 301. The working gas includes, but is not limited to, argon and air.

[0041] The first electrode 200 is disposed on the electrode base 100, and the second electrode 300 is disposed on the electrode base 100 insulated from the first electrode 200. The second electrode 300 is axially hollow to form an arc channel 301 and is sleeved outside the first electrode 200.

[0042] A magnetic device 500 is disposed on the second electrode 300. The magnetic device 500 can be wrapped around the second electrode 300 or embedded in the second electrode 300. The magnetic device 500 is used to form an axial magnetic field in the arc channel 301. The magnetic device 500 can be a permanent magnet or a current-carrying coil. It should be noted that one or more magnetic devices 500 can be disposed on the second electrode 300. When multiple magnetic devices 500 are disposed, each magnetic device 500 is arranged at intervals along the axial direction of the second electrode 300. By changing the magnetic devices 500 with different magnetic field strengths and directions, plasma generators with different operating power can be obtained.

[0043] A swirl ring 400 is disposed between the working gas flow channel 101 and the electric arc channel 301. Multiple vent holes are evenly distributed around the swirl ring 400. The working gas flow channel 101 and the electric arc channel 301 are connected through the vent holes. The center line of the vent holes does not pass through the axis of the swirl ring 400. That is, the vent holes are inclined or the two ends of the vent holes are twisted so that the airflow passing through the swirl ring 400 forms a rotating forward airflow under the guidance of the vent holes.

[0044] The swirl ring 400 can be fixed on the electrode base 100, or between the first electrode 200 and the second electrode 300, or between the first electrode 200 and the electrode base 100, or between the second electrode 300 and the electrode base 100. No specific limitation is made here, as long as the working gas flow channel 101 is connected to the arc channel 301 through the swirl ring 400.

[0045] In the embodiments of this application, the swirl ring 400 is uniformly arranged with 4 to 10 vent holes along the circumference, and the diameter of the vent holes is 1.1 mm to 3.5 mm. It should be noted that the number and diameter of the vent holes mentioned above are only a preferred and feasible solution provided by this application. Those skilled in the art can adjust the number and diameter of the holes as needed, and no limitation is made here.

[0046] like Figure 1As shown, in this application, the swirl ring 400 is in contact with the first electrode 200 and the second electrode 300 respectively. Therefore, the swirl ring 400 is made of insulating material. The swirl ring 400 includes a ring body. The inner wall surface of one end of the ring body is provided with an inner ring boss that protrudes inward along the radial direction of the ring body. The outer wall surface of the other end is provided with an outer ring boss that protrudes outward along the radial direction of the ring body. The inner ring boss is sleeved on the first electrode 200. The end face of the outer ring boss away from the inner ring boss is in contact with the end face of the second electrode 300.

[0047] Compared with the prior art, in the application of the magnetic spiral arc electrode provided in this application embodiment, one of the first electrode 200 and the second electrode 300 is connected to the positive terminal of the power supply, and the other is connected to the negative terminal of the power supply. That is, one of the first electrode 200 and the second electrode 300 is the anode and the other is the cathode. In a specific embodiment of this application, the first electrode 200 is connected to the negative terminal of the power supply as the cathode, and the second electrode 300 is connected to the positive terminal of the power supply as the anode.

[0048] After being energized, a strong electric field is formed between the first electrode 200 and the second electrode 300. The working gas enters the arc channel 301 through the working gas flow channel 101 and the swirling ring 400. Due to the inclined setting of the vent hole, the working gas forms a rotating gas flow field, which makes the distribution of the working gas in the arc channel 301 more uniform and the distribution of the plasma generated subsequently more uniform, thereby improving the stability and uniformity of the generated plasma.

[0049] At the same time, the magnetic device 500 provided at the second electrode 300 can increase the arc operating voltage in the arc channel 301 and reduce the operating current under the same power, thereby achieving the purpose of improving the electrode life.

[0050] Specifically, such as Figure 2 As shown, in one embodiment of this application, the magnetic device 500 is a ring-shaped permanent magnet. Here, a ring-shaped permanent magnet refers to a permanent magnet that is closed circumferentially. The ring-shaped permanent magnet is sleeved outside the second electrode 300, or embedded inside the second electrode 300, or the ring-shaped permanent magnet can be sleeved inside the second electrode 300. In practical applications, plasma generators with different operating powers can be obtained by changing the length, diameter, magnetic field strength, and direction of the permanent magnet. In this embodiment, the permanent magnet is axially magnetized, the magnetic field direction is consistent with the working gas flow direction, and the magnetic field strength ranges from 100GS to 2000GS.

[0051] The material of the permanent magnet can be an aluminum-nickel-cobalt permanent magnet alloy, an iron-chromium-cobalt permanent magnet alloy, a permanent magnet ferrite, a rare earth permanent magnet material, a composite permanent magnet material, or other permanent magnet materials known in the art.

[0052] It should be noted that the magnetic device 500 may include multiple permanent magnets evenly distributed along the circumference, that is, the permanent magnets are in the shape of arc blocks, and multiple permanent magnets are spliced ​​together in the circumference to form a ring-shaped magnetic device 500.

[0053] To further improve arc stability, such as Figure 2 As shown, the end of the first electrode 200 away from the electrode base 100 is the first arc-starting structure. The first arc-starting structure includes a columnar outer peripheral surface 201, a first conical surface 202, and an electrode end surface 203 connected in sequence from near to far from the electrode base 100. The first conical surface 202 gradually tapers from the end connected to the columnar outer peripheral surface 201.

[0054] The inner wall surface of the arc channel 301 near the electrode base 100 is a second arc-starting structure. The second arc-starting structure is sleeved outside the first arc-starting structure. The second arc-starting structure includes a first columnar inner circumferential surface 302, a second conical surface 303, and a second columnar inner circumferential surface 304 connected in order from near to far from the electrode base 100. The second conical surface 303 gradually tapers from the end connected to the first columnar inner circumferential surface 302.

[0055] An arc-starting cavity is formed between the first arc-starting structure and the second arc-starting structure. The gap between the first arc-starting structure and the second arc-starting structure is precisely designed to ensure a uniform electric field distribution, which can efficiently excite the working gas to form plasma.

[0056] The magnetic arc electrode in this embodiment adopts a high-frequency arc initiation method. Through an external high-frequency arc initiator, firstly, arcing occurs between the columnar outer peripheral surface 201 of the first electrode 200 and the first columnar inner peripheral surface 302 of the second electrode 300, ionizing and conducting the working gas in the arc initiation cavity to form an electric arc. Then, driven by the working gas, the arc root of the arc on the first electrode 200 moves from the columnar outer peripheral surface 201 through the first conical surface 202 and finally stabilizes at the center of the electrode end face 203. The arc root of the arc on the second electrode 300 moves downstream from the first columnar inner peripheral surface 302 to the second conical surface 303 and the second columnar inner peripheral surface 304, and finally balances on the second columnar inner peripheral surface 304 near the opening of the arc channel 301.

[0057] like Figure 3As shown, in another embodiment of this application, the inner wall surface of the arc channel 301 further includes a third conical surface 305, a third columnar inner peripheral surface 306, a fourth conical surface 307, and a fourth columnar inner peripheral surface 308, which are connected sequentially from near to far from the electrode base 100 to the end of the second columnar inner peripheral surface 304 away from the second conical surface 303. The third conical surface 305 gradually tapers from the end connected to the second columnar inner peripheral surface 304, and the fourth conical surface 307 gradually expands from the end connected to the third columnar inner peripheral surface 306. The second electrode 300 with this structure is more suitable for application in the fields of pulverized coal ignition and waste gas treatment.

[0058] The above-mentioned electrode optimization design enables the plasma generator to operate normally under low power conditions, thereby reducing the energy consumption of the equipment and meeting the requirements of energy conservation and environmental protection.

[0059] In another embodiment, such as Figure 4 As shown, the second electrode 300 includes an arc-starting electrode 310 and an output electrode 320. The arc-starting electrode 310 and the output electrode 320 can be connected in various ways, such as detachable connections such as threaded connections or threaded fastener connections, or fixed connections such as welding. No limitation is made here.

[0060] The inner wall surface of the end of the arc-starting electrode 310 away from the output electrode 320 is a second arc-starting structure. The inner wall surface of the end of the output electrode 320 connected to the arc-starting electrode 310 is composed of a third conical surface 305, a third columnar inner circumferential surface 306, a fourth conical surface 307, and a fourth columnar inner circumferential surface 308. At least one of the arc-starting electrode 310 and the output electrode 320 is provided with a magnetic device 500.

[0061] Specifically, in one embodiment of this application, the arc-starting electrode 310 is threadedly connected to the output electrode 320.

[0062] like Figure 4 As shown, the arc-starting electrode 310 is provided with a magnetic device 500, which is sleeved on the outer wall surface of the arc-starting electrode 310 at the position corresponding to the second columnar inner circumferential surface 304, and / or, the output electrode 320 is provided with a magnetic device 500, which is sleeved on the outer wall surface of the output electrode 320 at the position corresponding to the fourth columnar inner circumferential surface 308.

[0063] The magnetic device 500 can be provided only on the arc-starting electrode 310, or only on the output electrode 320, or both the arc-starting electrode 310 and the output electrode 320 can be provided simultaneously. Arranging permanent magnets on the outside of the arc-starting electrode 310 and the output electrode 320 can help improve the service life of the second electrode and reduce operating costs.

[0064] like Figure 4 As shown, in one specific embodiment, the arc-starting electrode 310 is provided with a first permanent magnet 501 at a position corresponding to the second columnar inner circumferential surface 304. The length of the first permanent magnet 501 is 50% to 80% of the axial length of the second columnar inner circumferential surface 304 of the arc-starting electrode 310.

[0065] A second permanent magnet 502 is disposed at the position of the output electrode 320 corresponding to the fourth columnar inner circumferential surface 308. The length of the second permanent magnet 502 is 50% to 100% of the axial length of the fourth columnar inner circumferential surface 308 of the output electrode 320. Arranging permanent magnets on the outside of the arc-starting anode and the output anode can make the generated plasma spiral forward under the action of the Lorentz force of the magnetic field, increasing the probability of plasma collision. This not only improves working efficiency, but also helps to extend the service life of the second electrode 300 and reduce operating costs.

[0066] The outer wall of the arc-starting electrode 310 is stepped, that is, the outer wall of the arc-starting electrode 310 includes a large-diameter circumferential wall and a small-diameter circumferential wall. The arc-starting electrode 310 and the output electrode 320 are connected at the end of the small-diameter circumferential wall away from the large-diameter circumferential wall. An annular stepped surface is formed between the small-diameter circumferential wall and the large-diameter circumferential wall, facing the output electrode 320. When the arc-starting electrode 310 and the output electrode 320 are connected, the small-diameter circumferential wall, the annular stepped surface and the end face of the end of the output electrode 320 connected to the arc-starting electrode 310 form a limiting groove for accommodating the magnetic device 500. The annular stepped surface and the end face of the end of the output electrode 320 connected to the arc-starting electrode 310 provide axial limiting for the magnetic device 500.

[0067] This application also provides a plasma generator, which includes the magnetic spiral arc electrode as described in the above embodiments. Since the plasma generator uses the magnetic spiral arc electrode, the technical effect of the plasma generator can be referred to the above embodiments.

[0068] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "a," and / or "the" are not specifically singular and may include the plural. Generally, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements. An element defined by the phrase "comprising an..." does not exclude the presence of other identical elements in the process, method, product, or apparatus that includes the element.

[0069] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0070] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0071] This article uses specific examples to illustrate the principles and implementation methods of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand the core ideas of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principles of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

Claims

1. A magnetic spiral arc electrode, characterized in that, include: Electrode base (100), wherein the electrode base (100) is provided with working gas flow channel (101); The first electrode (200) is disposed on the electrode base (100); The second electrode (300) is disposed on the electrode base (100) insulated from the first electrode (200). The second electrode (300) is axially hollow to form an arc channel (301) and is sleeved on the outside of the first electrode (200). A magnetic device (500) is disposed on the second electrode (300), the magnetic device (500) being used to generate an axial magnetic field within the arc channel (301); A swirl ring (400) is disposed between the working gas flow channel (101) and the electric arc channel (301). The swirl ring (400) has a plurality of vent holes evenly distributed along its circumference. The working gas flow channel (101) and the electric arc channel (301) are connected through the vent holes. The center line of the vent holes is inclined relative to the axis of the swirl ring (400) and does not pass through the axis of the swirl ring (400).

2. The magnetic spiral arc electrode according to claim 1, characterized in that, The magnetic device (500) is a ring-shaped permanent magnet, which is sleeved outside the second electrode (300) or embedded inside the second electrode (300).

3. The magnetic spiral arc electrode according to claim 1, characterized in that, The end of the first electrode (200) away from the electrode base (100) is a first arc-starting structure. The first arc-starting structure includes a columnar outer peripheral surface (201), a first conical surface (202), and an electrode end surface (203) connected in sequence from near to far from the electrode base (100). The first conical surface (202) gradually tapers from the end connected to the columnar outer peripheral surface (201).

4. The magnetic spiral arc electrode according to claim 3, characterized in that, The inner wall surface of the arc channel (301) near the electrode base (100) is a second arc-starting structure. The second arc-starting structure is sleeved outside the first arc-starting structure. The second arc-starting structure includes a first columnar inner circumferential surface (302), a second conical surface (303), and a second columnar inner circumferential surface (304) connected in order from near to far from the electrode base (100). The second conical surface (303) gradually tapers from the end connected to the first columnar inner circumferential surface (302).

5. The magnetic spiral arc electrode according to claim 4, characterized in that, The inner wall of the arc channel (301) also includes a third conical surface (305), a third columnar inner circumferential surface (306), a fourth conical surface (307), and a fourth columnar inner circumferential surface (308) connected sequentially from near to far from the electrode base (100) to the end of the second columnar inner circumferential surface (304) away from the second conical surface (303). The third conical surface (305) gradually narrows from the end connected to the second columnar inner circumferential surface (304), and the fourth conical surface (307) gradually expands from the end connected to the third columnar inner circumferential surface (306).

6. The magnetic spiral arc electrode according to claim 5, characterized in that, The second electrode (300) includes an arc-starting electrode (310) and an output electrode (320) connected coaxially. The inner cavity of the arc-starting electrode (310) is connected to the inner cavity of the output electrode (320) to form the arc channel (301). The inner wall surface of the arc-starting electrode (310) at the end away from the output electrode (320) is the second arc-starting structure. The magnetic device (500) is disposed on the arc-starting electrode (310) and / or the output electrode (320). The inner wall surface of the arc-starting electrode (310) is composed of the first columnar inner peripheral surface (302), the second conical surface (303), and the second columnar inner peripheral surface (304). The inner wall surface of the output electrode (320) is composed of the third conical surface (305), the third columnar inner peripheral surface (306), the fourth conical surface (307), and the fourth columnar inner peripheral surface (308).

7. The magnetic spiral arc electrode according to claim 6, characterized in that, The arc-starting electrode (310) is threadedly connected to the output electrode (320).

8. The magnetic spiral arc electrode according to claim 6, characterized in that, The arc-starting electrode (310) is provided with the magnetic device (500), and the magnetic device (500) is sleeved on the outer wall surface of the arc-starting electrode (310) at the position corresponding to the second columnar inner circumferential surface (304).

9. The magnetic spiral arc electrode according to claim 6, characterized in that, The output electrode (320) is provided with the magnetic device (500), and the magnetic device (500) is sleeved on the outer wall surface of the output electrode (320) corresponding to the fourth columnar inner circumferential surface (308).

10. A plasma generator, characterized in that, Includes the magnetic spiral arc electrode as described in any one of claims 1-9.

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