Plasma arc powder preparation equipment

Abstract

A plasma arc powder preparation device includes a discharging mechanism, a reactor, a positive electrode, a negative electrode and a magnetron. The discharging mechanism includes a feeding pipe and a jet nozzle. The feeding pipe is used for conveying raw materials, and the jet nozzle is used for supplying compressed gas. The reactor includes a cylinder body and a top cover. The top cover is provided with a feeding hole, and the feeding pipe together with the jet nozzle is positioned at the feeding hole. The negative electrode and the positive electrode are used for generating an arc and ionizing the compressed gas fed into the inner cavity through the jet nozzle into plasma to form a plasma arc. The magnetron is provided with a main magnetic pole and a sub-magnetic pole. The main magnetic pole generates a rotating magnetic field that causes the plasma arc to rotate, and the sub-magnetic pole generates a magnetic field that radially pushes the plasma arc inward.

Description

Technical Field

[0001] The present disclosure relates to the field of powder preparation, and more particularly to a plasma arc powder preparation device. Background Art

[0002] Due to the continuous progress and development of modern science and technology, people's demands for the popularization of 3D printing technology, the large-scale application of semiconductor components, infrared optical lenses, etc., and the increasing demand for new energy batteries and energy storage equipment are growing. All walks of life have higher and higher requirements for the purity and particle size of powder materials (for example, the application of nanomaterials), and the requirements are getting finer and finer, and the demand is also increasing. Therefore, the technical requirements for equipment used to prepare powder materials with higher and higher purity and finer and finer particle size are becoming more and more advanced, and the demand for production capacity is also increasing.

[0003] The Chinese Patent Application Publication No. CN111495298A, published on August 7, 2020, discloses a plasma arc magnetic force rotary gasification powder making furnace, in which the ends of the first electrode and the second graphite electrode are opposite in the up and down direction, and metal raw materials are added from the feeding port above the lateral sides of the first electrode and the second graphite electrode into a frustum-shaped or cylindrical one-piece stainless steel crucible. The first electrode is arranged on the bottom wall of the crucible and contacts the metal raw materials already added into the stainless steel crucible. The second graphite electrode is inserted into the crucible from above. A plasma arc is formed between the second graphite electrode and the metal raw materials already added into the stainless steel crucible to melt and gasify the metal raw materials. The gasified metal raw materials are oxidized and cooled by the suction of the dust collection hood to form nano-scale oxidized powder. The Chinese Patent Application CN105234424A, published on January 13, 2016, discloses a process for producing nano-silver powder by arc furnace gasification. In this process, electrolytic silver powder is loaded into the evaporation gasification system furnace. In this system, a graphite carbon rod is used as the cathode and electrolytic silver powder is used as the anode. The cathode and the anode are briefly contacted to connect the power supply to cause a short circuit, and then the cathode and the anode are separated by a certain distance to generate a high-temperature arc between the cathode and the anode, melting and evaporating the metal continuously. The vaporized silver powder particles then enter the particle control system, where the silver metal atoms are rapidly cooled into nano-particles.

[0004] Two patent documents adopt a similar technical route, that is, metal raw materials / electrolytic silver powder (collectively referred to as metal materials) are used as the other pole of the arc, which makes it inconvenient to adjust the distance between the graphite electrode and the metal materials. In addition, the addition of the metal raw materials in CN111495298A is based on the liquid level of the metal raw materials in the crucible to achieve continuous feeding, resulting in limited powder production capacity. Moreover, based on the melting and evaporation of the metal materials in the crucible / evaporation and gasification system furnace by the plasma arc / high-temperature arc, since the metal materials are in a piled-up state in the crucible / evaporation and gasification system furnace, the amount of melting and evaporation of the metal materials is limited, thereby limiting the powder preparation efficiency. In addition, CN111495298A uses a one-piece stainless steel crucible. Using a one-piece stainless steel crucible has the risk that the plasma arc or the drifting arc of the plasma arc contacts the stainless steel crucible, resulting in ablation of the stainless steel crucible, and even the plasma arc or the drifting arc of the plasma arc flows inside the crucible and pierces the crucible. In addition, the plasma arc generated in the similar technical routes adopted by the two patent documents is not radially constrained, that is, there is a risk that the plasma arc or the drifting arc of the plasma arc contacts the inner wall of the evaporation and gasification system furnace / crucible, resulting in ablation of the inner wall of the evaporation and gasification system furnace / crucible. Furthermore, the inner wall of the evaporation and gasification system furnace / crucible is ablated to produce contamination of the prepared powder by the material of the inner wall of the evaporation and gasification system furnace / crucible, affecting the purity of the prepared powder. Summary of the Invention

[0005] In view of the problems existing in the background technology, one object of the present disclosure is to provide a plasma arc powder preparation device, which can avoid the risk that the plasma arc or the drifting arc of the plasma arc contacts the cylinder body and then ablates the cylinder body.

[0006] In view of the problems existing in the background technology, another object of the present disclosure is to provide a plasma arc powder preparation device, which can improve the production capacity and the powder preparation efficiency.

[0007] Accordingly, a plasma arc powder preparation device includes a discharging mechanism, a reactor, a positive electrode, a negative electrode, and a magnetron. The discharging mechanism is used to supply raw materials for preparing the powder. The discharging mechanism includes a feeding pipe and a jet nozzle. The feeding pipe is used to convey the raw materials for preparing the powder. The feeding pipe is located between the positive electrode and the negative electrode. The jet nozzle enters the interior of the feeding pipe from the outside and extends downward inside the feeding pipe and is spaced apart from the inner wall of the feeding pipe. The jet nozzle is used to supply compressed gas. The reactor includes a cylinder body and a top cover. The cylinder body includes an inner cavity. The top cover is provided with a feeding hole, and the feeding pipe together with the jet nozzle is positioned at the feeding hole. The positive electrode and the negative electrode are used to connect to the circuit of a DC plasma power supply. The positive electrode and the negative electrode are used to extend into the inner cavity of the cylinder body. The negative electrode and the positive electrode are used to generate an arc between their ends and ionize the compressed gas supplied into the inner cavity of the cylinder body through the jet nozzle into plasma to form a plasma arc. The magnetron is provided with a cylindrical shell and circumferentially alternating and spaced main magnetic poles and sub-magnetic poles arranged on the inner wall of the cylindrical shell. The main magnetic poles and the sub-magnetic poles are radially located between the cylindrical shell and the cylinder body of the reactor and are radially spaced apart from the cylinder body of the reactor. The main magnetic poles are connected to a DC plasma power supply to generate a rotating magnetic field that rotates the plasma arc. The sub-magnetic poles are connected to a three-phase AC power supply to generate a magnetic field that radially pushes the plasma arc inward.

[0008] The beneficial effects of the present disclosure are as follows.

[0009] Compared with the plasma magnetic force rotary gasification pulverizing furnace in the background art that uses a metal material as the other pole of the arc, in the plasma arc powder preparation equipment of the present disclosure, by using a positive electrode and a negative electrode, the distance between the positive electrode and the negative electrode can be adjusted more flexibly, precisely and effectively, and then the temperature of the plasma arc in the inner cavity of the cylinder can be adjusted flexibly, precisely and in real time; on the basis of using the positive electrode and the negative electrode, the raw material for preparing the powder can be supplied from outside the cylinder of the reactor to the inside of the cylinder of the reactor, and the conveying amount of the raw material of the powder can be flexibly matched with the thermal energy of the plasma arc formed by the ionized gas generated by the stable arc between the positive electrode and the negative electrode. The preparation of the powder can be carried out continuously without being restricted by the internal volume of the cylinder or the raw material in the cylinder, improving the production capacity of the plasma arc powder preparation equipment; the feed pipe together with the jet nozzle is positioned at the feed hole, so that the raw material supplied by the feed pipe of the discharging mechanism and the compressed gas supplied by the jet nozzle enter the inner cavity of the cylinder. Through the jet nozzle entering the inside of the feed pipe, the jet nozzle uses the compressed gas to supply the raw material conveyed by the feed pipe into the reactor. The raw material conveyed by the feed pipe will form an annular distribution around the compressed gas ejected by the jet nozzle at the outlet of the jet nozzle. Through the positional relationship between the feed pipe located between the positive electrode and the negative electrode and the volume relationship between the jet nozzle and the cylinder, the compressed gas carrying the annularly distributed raw material and flowing downward into the cylinder of the cylinder is ionized into plasma and plasma arc by the arc formed between the positive electrode and the negative electrode. Then the plasma arc will melt and gasify the raw material entering the inner cavity of the cylinder along with the compressed gas through the feed hole to form powder. Among them, the compressed gas entering the inner cavity of the cylinder through the jet nozzle and entering between the ends of the negative electrode and the positive electrode causes the formed plasma arc to expand radially outward. Specifically, the compressed air expands radially outward due to the pressure change when entering the cylinder of the cylinder, and at the same time, the compressed air expands in volume due to the heat of the plasma arc, further causing the plasma arc to expand outward, resulting in the formed plasma arc expanding radially outward (that is, the high-temperature region at the center of the plasma arc also expands radially outward), so that the annular raw material and the plasma arc are fully stirred, contacted and heat-exchanged to be melted and gasified to form powder, thereby improving the powder preparation efficiency.

[0010] A rotating magnetic field for forming a rotating plasma arc is formed by a main magnetic pole. The action of the rotating magnetic field restricts and elongates the arc formed between the positive electrode and the negative electrode, and further stabilizes the formed plasma arc. The rotating plasma arc drives the raw material to rotate, thereby enhancing the stirring and heat exchange effect on the raw material, making the raw material melt and gasify more uniformly, obtaining a more consistent powder, and obtaining a more stable amount of powder. A magnetic field for radially pushing the plasma arc inward is generated by an auxiliary magnetic pole. Similarly, this radially inward pushing effectively enhances the stirring in cooperation with the radially outward pushing generated by the expanding compressed gas in the middle that the raw material undergoes, so that the part of the raw material in the radially outward direction moves radially inward and approaches the high temperature of the plasma arc, thereby making the overall heat exchange of the raw material uniform, the melting balanced, and the particle size of the formed powder uniform. In addition, the magnetic field generated by the auxiliary magnetic pole for radially pushing the plasma arc inward will prevent the plasma arc or the drifting arc of the plasma arc from approaching the inner wall surface of the cylinder body (i.e., the surface of the lobe facing the inner cavity side), avoiding the risk that the plasma arc or the drifting arc of the plasma arc contacts the cylinder body and causes the cylinder body to be ablated in the cylinder body (i.e., the inner wall surface of the cylinder body), and further eliminating the risk that the plasma arc or the drifting arc of the plasma arc flows through and breaks through the cylinder body in the cylinder body, thereby improving the working stability and working life of the reactor. From this perspective, the magnetic field generated by the auxiliary magnetic pole for radially pushing the plasma arc inward also plays a role in stabilizing the plasma arc. In addition, based on avoiding the risk that the plasma arc or the drifting arc of the plasma arc contacts the cylinder body and causes the cylinder body to be ablated in the cylinder body (i.e., the inner wall surface of the cylinder body), the pollution of the prepared powder caused by the material of the cylinder body due to ablation of the cylinder body is avoided, and the purity of the prepared powder is improved. Description of the Drawings

[0011] Figure 1 is a perspective view of a plasma arc powder preparation device according to the present disclosure.

[0012] Figure 2 is Figure 1 a perspective view of some components of

[0013] Figure 3 is Figure 2 a cross-sectional view of

[0014] Figure 4 is Figure 3 a partially enlarged view marked by a dotted circle in the upper part of

[0015] Figure 5 is Figure 3 a partially enlarged view marked by a dotted circle in the middle of

[0016] Figure 6 is Figure 3 a partially enlarged view of

[0017] Figure 7 yes Figure 6 A cross-sectional view of the feed pipe and the air jet nozzle of the unloading mechanism.

[0018] Figure 8 yes Figure 6 A top perspective view of some components.

[0019] Figure 9 yes Figure 8 A three-dimensional diagram of some components.

[0020] Figure 10 yes Figure 9 A three-dimensional diagram of some components.

[0021] Figure 11 yes Figure 9 A three-dimensional diagram of the cylinder in FIG.

[0022] Figure 12 yes Figure 9 A three-dimensional view of one of the valves of the cylinder.

[0023] Figure 13 yes Figure 9 A three-dimensional view of one of the insulators of a cylinder.

[0024] Figure 14 It is a top perspective view of the top cover of the reactor.

[0025] Figure 15 It is a bottom perspective view of the top cover of the reactor.

[0026] Figure 16 It is a top perspective view of the upper heat-resistant insulating pad of the reactor.

[0027] Figure 17 It is a bottom-up stereoscopic view of the upper heat-resistant insulating pad of the reactor.

[0028] Figure 18 It is a bottom-up stereoscopic view of the lower heat-resistant insulating pad of the reactor.

[0029] Figure 19 It is a top perspective view of the lower heat-resistant insulating pad of the reactor.

[0030] Figure 20 It is a top perspective view of the connection flange of the sedimentation chamber.

[0031] Figure 21 It is a top view of the magnetron.

[0032] Figure 22 yes Figure 21 A top view of the plasma arc is shown showing the positive electrode, negative electrode and plasma arc.

[0033] The reference numerals are described as follows:

[0034] 100 Plasma arc powder preparation equipment, lower nut at 25B

[0035] D, up and down direction, 26 Ring cylinder

[0036] 1 Discharging mechanism, 27 Adapter pipe

[0037] 10 Feeding pipe, 28 Lower heat-resistant insulating pad

[0038] 101 Inverted cone section, 281 Lower ring body

[0039] 102 Straight cylinder section, 281a Top flat surface

[0040] 11 Jet nozzle, 281b Lower annular channel

[0041] 111 Elbow section, 281b1 Communication port

[0042] 112 Tip section, 281c Bottom flat surface

[0043] 12 Motor, 281d Central hole

[0044] 13 Reducer, 282 Lower stack body

[0045] 14 Housing, 282a Exhaust port

[0046] 15 Rotor impeller, S Receiving groove

[0047] 16 Upper funnel, G Accommodating groove

[0048] 17 Lower outlet, 3A Positive electrode

[0049] 2 Reactor, 3B Negative electrode

[0050] 21 Cylinder body, 4 Magnetron

[0051] 210 Inner cavity, 41 Cylindrical outer shell

[0052] 211 Petal body, 42 Main magnetic pole

[0053] 211a Upper lying block, 421 First magnetic conductor

[0054] 211b Upper vertical block, 421a Inner side surface

[0055] 211b1 Upper through hole, 421b Peripheral surface

[0056] 211c Lower vertical block, 422 First winding

[0057] 211c1 Lower through hole, 43 Sub magnetic pole

[0058] 211d Upper pipe section, 431 Second magnetic conductor

[0059] Inner surface of the lower pipe section 431a

[0060] Circumferential surface of the upper connection block 431b

[0061] Second winding of the lower flat block 432

[0062] Upper annular insulating member of the insulator 44

[0063] Lower annular insulating member of the upper pipe joint 45

[0064] Lower pipe joint 46 of the air inlet pipe

[0065] Positive electrode conveying mechanism of the top cover 5A

[0066] Hole for positive electrode of the negative electrode conveying mechanism 5B

[0067] Hole for negative electrode of the roller pair 51

[0068] Feeding hole 6 of the sedimentation chamber

[0069] Air inlet hole 61 of the top plate

[0070] Flange 62 of the barrel body

[0071] Bottom side plane 63 of the exhaust pipe

[0072] Annular air inlet groove 64 of the connecting flange

[0073] Upper heat-resistant insulating pad 641 of the top side plane

[0074] Upper ring body 641a of the annular air inlet passage

[0075] Upper flat surface 642 of the air inlet port

[0076] Upper annular channel 643 of the central perforation

[0077] Communication hole 65A of the first water inlet port

[0078] Lower flat surface 65B of the second water inlet port

[0079] Central hole 66 of the ventilation unit

[0080] Stack body 661 of the cylinder

[0081] Outlet 662 of the air needle

[0082] Upper bolt 7 of the receiving bin

[0083] Lower bolt 8 of the observation window

[0084] 25A Upper Nut 9 Vision Control Sensor Detailed Implementation Manner

[0085] The accompanying drawings illustrate embodiments of the present disclosure, and it will be understood that the disclosed embodiments are merely examples of the present disclosure, and the present disclosure can be implemented in various forms. Therefore, the specific details disclosed herein should not be construed as limiting, but only as a basis for the claims and as a representative basis for teaching those of ordinary skill in the art to implement the present disclosure in various ways.

[0086] Referring to Figures 1 to 11 , the plasma arc powder preparation device 100 includes a discharging mechanism 1, a reactor 2, a positive electrode 3A, and a negative electrode 3B.

[0087] As Figure 2 , Figure 4 , Figure 6 and Figure 7 shown, the discharging mechanism 1 is used to supply the raw materials for preparing the powder. The discharging mechanism 1 includes a feeding pipe 10 and a jet nozzle 11. The feeding pipe 10 is used to convey the raw materials for preparing the powder. The feeding pipe 10 is located between the positive electrode 3A and the negative electrode 3B. The jet nozzle 11 enters the inside of the feeding pipe 10 from the outside and extends downward inside the feeding pipe 10 and is spaced apart from the inner wall of the feeding pipe 10. The jet nozzle 11 is used to supply compressed gas.

[0088] As Figures 3 to 5 and Figures 8 to 15 shown, the reactor 2 includes a cylinder body 21 and a top cover 22. The cylinder body 21 includes an inner cavity 210. The top cover 22 is provided with a feeding hole 223. The feeding hole 223 is for positioning the feeding pipe 10 together with the jet nozzle 11 thereat.

[0089] The positive electrode 3A and the negative electrode 3B are used to connect to the circuit of the DC plasma power supply. The positive electrode 3A and the negative electrode 3B are used to extend into the inner cavity 210 of the cylinder body 21. The negative electrode 3B and the positive electrode 3A are used to form an arc between their ends and ionize the compressed gas supplied through the jet nozzle 11 into plasma in the inner cavity 210 of the cylinder body 21 to form a plasma arc.

[0090] Compared with the plasma magnetic force rotating gasification powder-making furnace in the background art that uses a metal material as the other pole of the arc, in the plasma arc powder preparation device 100 of the present disclosure, by using the positive electrode 3A and the negative electrode 3B, the distance between the positive electrode 3A and the negative electrode 3B can be adjusted more flexibly, precisely and actually, and then the temperature of the plasma arc in the inner cavity 210 of the cylinder 21 can be adjusted flexibly, precisely and in real time; on the basis of using the positive electrode 3A and the negative electrode 3B, the raw materials for preparing the powder can be supplied from outside the cylinder 21 of the reactor 2 into the cylinder 21 of the cylinder 21, and the conveying amount of the raw materials of the powder can be flexibly matched with the thermal energy of the plasma arc formed by the ionized gas generated by the stable arc between the positive electrode 3A and the negative electrode 3B. The preparation of the powder can be carried out continuously without being restricted by the internal volume of the cylinder 21 or the raw materials in the cylinder 21, improving the production capacity of the plasma arc powder preparation device 100; the feed pipe 10 together with the jet nozzle 11 is positioned at the feed hole 223, so that the raw materials supplied by the feed pipe 10 of the discharging mechanism 1 and the compressed gas supplied by the jet nozzle 11 enter the inner cavity 210 of the cylinder 21. Through the jet nozzle 11 entering the inside of the feed pipe 10, the jet nozzle 11 uses the compressed gas to supply the raw materials conveyed by the feed pipe 10 into the reactor 2. The raw materials conveyed by the feed pipe 10 will form an annular distribution around the compressed gas ejected from the jet nozzle 11 at the outlet of the jet nozzle 11. Through the positional relationship between the feed pipe 10 located between the positive electrode 3A and the negative electrode 3B and the volume relationship between the jet nozzle 11 and the cylinder 21, the compressed gas carrying the annularly distributed raw materials and flowing downward into the cylinder 21 of the cylinder 21 is ionized into plasma and plasma arc by the arc formed between the positive electrode 3A and the negative electrode 3B. Then, the plasma arc will melt and gasify the raw materials entering the inner cavity 210 of the cylinder 21 through the feed hole 223 along with the compressed gas to form powder. Among them, the compressed gas entering the inner cavity 210 of the cylinder 21 through the jet nozzle 11 and entering between the ends of the negative electrode 3B and the positive electrode 3A causes the formed plasma arc to expand radially outward. Specifically, the compressed air expands radially outward due to the pressure change when entering the cylinder 21 of the cylinder 21, and at the same time, the compressed air expands in volume due to the heat of the plasma arc, further causing the plasma arc to expand outward, resulting in the formed plasma arc expanding radially outward (that is, the high-temperature region at the center of the plasma arc also expands radially outward), so that the annular raw materials and the plasma arc are fully stirred, contacted and heat-exchanged to be melted and gasified to form powder, thereby improving the powder preparation efficiency.

[0091] As Figure 7As shown, the jet nozzle 11 transversely enters the interior of the material conveying pipe 10 and bends downward inside the material conveying pipe 10, so as to avoid interference with other components of the unloading mechanism 1 above the material conveying pipe 10 caused by arranging the jet nozzle 11 extending in the same direction as the material conveying pipe 10, and make full use of the space on the side of the material conveying pipe 10 to conveniently arrange the jet nozzle 11. Further, in Figure 7Among them, the material conveying pipe 10 includes an inverted conical barrel portion 101 and a straight cylindrical barrel portion 102 that communicate with each other. The inverted conical barrel portion 101 is used to receive the raw materials for preparing the powder. The straight cylindrical barrel portion 102 is connected to the inverted conical barrel portion 101 from below, and the lower end of the straight cylindrical barrel portion 102 is positioned at the feed hole 223; the air jet nozzle 11 includes a bent pipe portion 111 and a pointed nozzle portion 112 that communicate with each other. The bent pipe portion 111 penetrates into the inverted conical barrel portion 101 of the material conveying pipe 10 and enters the inside of the inverted conical barrel portion 101 and bends downward inside the inverted conical barrel portion 101. The pointed nozzle portion 112 extends downward from the end of the bent pipe portion 111 and centrally extends into the straight cylindrical barrel portion 102. By adopting the inverted conical barrel portion 101, making full use of the speed regulation and convergence functions of the inclined plane gravity drop of the inverted conical barrel portion 101, it can make the speed of the annular raw materials formed at the connection part of the inverted conical barrel portion 101 and the straight cylindrical barrel portion 102 match the speed of the raw materials supplied by the discharging mechanism 1, without causing accumulation; by the pointed nozzle portion 112 centrally extending into the straight cylindrical barrel portion 102, the compressed air bulging out from the pointed nozzle portion 112 will, due to the pressure difference between the outlet of the pointed nozzle portion 112 and the pressure inside the straight cylindrical barrel portion 102, push the raw materials entering from the space between the inverted conical barrel portion 101 and the pointed nozzle portion 112 radially towards the inner wall of the cylindrical barrel portion 102. At this time, on the one hand, the compressed gas will prevent the air from the inverted conical barrel portion 101 from entering. This is especially applicable when the compressed gas is an inert gas. That is, when the compressed gas is an inert gas, an isolation of the air from the inverted conical barrel portion 101 will be formed within the radial range at the outlet of the pointed nozzle portion 112 (this is beneficial to ensuring the purity of the non-oxidized powder prepared when preparing the non-oxidized powder). On the other hand, the compressed air entering the cylindrical barrel portion 102 flows downward to drive the raw materials around the compressed air to enter the inner cavity 210 of the cylinder body 21 in such a way that the compressed air is in the middle and the raw materials are around the compressed air. When entering the inner cavity 210 of the cylinder body 21, similarly, due to the pressure difference between the compressed air and the inner cavity 210 of the cylinder body 21, the raw materials expand radially outward. The radially outward expanding raw materials and the intermediate compressed air enter downward between the ends of the negative electrode 3B and the positive electrode 3A. The arc ionizes the compressed air into a plasma arc. At the same time, the compressed air expands in volume due to the heat of the plasma arc, further causing the plasma arc to expand outward and come into full contact with the raw materials for stirring and heat exchange, melting and vaporizing to form a powder. The compressed air input by the air jet nozzle 11 is the working gas for forming the plasma. The working gas can be any suitable gas, such as an inert gas, hydrogen, oxygen, air, etc., and can be selected according to whether the prepared powder is a non-oxidized powder or an oxidized powder. If an inert gas is used to prepare a non-oxidized powder, as mentioned above, the inert gas can also play a role in isolating the air at the inverted conical barrel portion 101 to improve the purity of the prepared non-oxidized powder.

[0092] In Figures 1 to 6 it, the material conveying pipe 10 is in a standing state.

[0093] The discharging mechanism 1 can adopt any suitable structure. For example, as Figure 6 shown, the discharging mechanism 1 is a star-shaped discharger. The star-shaped discharge valve has the characteristics of discharging quantitatively and continuously, which will be organically combined with the feeding pipe 10 with an inverted conical part 101 and a straight cylindrical part 102, so as to match the speed of the annular raw material formed at the connecting part of the inverted conical part 101 and the straight cylindrical part 102 with the raw material supplied by the discharging mechanism 1, and further match the speed of the annular raw material entering the inner cavity 210 of the cylinder body 21 with the raw material supplied by the discharging mechanism 1, and then can flexibly match the conveying amount of the raw material for preparing the powder with the heat energy of the plasma arc formed by the ionized gas generated by the stable arc between the positive electrode 3A and the negative electrode 3B.

[0094] Specifically, as Figure 6 shown, the star-shaped discharger further includes a motor 12, a speed reducer 13, a housing 14, a rotor impeller 15, an upper funnel 16 and a lower outlet 17. The motor 12 is connected to the speed reducer 13, the speed reducer 13 is connected to the rotor impeller 15, the housing 14 surrounds the rotor impeller 15, the upper funnel 16 is connected to the top side of the housing 14 and is open up and down, the lower outlet 17 is connected to the bottom side of the housing 14 and is opposite and communicated with the upper funnel 16 in the up-down direction D, and the rotor impeller 15 is located between the upper funnel 16 and the lower outlet 17. The upper funnel 16 is used to hold the raw material for preparing the powder. By controlling the rotation speed of the rotor impeller 15 through the motor 12 and the speed reducer 13, the discharging speed of the rotor impeller 15 to the lower outlet 17 can be realized. The size of the raw material can be determined according to the requirements of the prepared powder. For example, when preparing nano-scale powder, the raw material can be micron-scale particles, such as but not limited to particles of 100 μm. The material of the raw material is not limited as long as it can be used to form powder through the plasma arc. The raw material can be metal or non-metal.

[0095] Referring to Figure 14 and Figure 15 , the top cover 22 is provided with a positive electrode hole 221 and a negative electrode hole 222; the positive electrode 3A and the negative electrode 3B respectively extend into the inner cavity 210 of the cylinder body 21 through the positive electrode hole 221 and the negative electrode hole 222.

[0096] Referring to Figure 3 and Figure 4 , Figures 14 to 17, the top cover 22 of the reactor 2 is provided with an air inlet hole 224 and a flange 225. The air inlet hole 224 is used to connect to the gas supplied externally. The flange 225 has a bottom side plane 225a, and an annular air inlet groove 225b is provided on the bottom side plane 225a. The annular air inlet groove 225b is recessed upward from the bottom side plane 225a and communicates with the air inlet hole 224. The reactor 2 further includes an upper heat-resistant insulating pad 23. The upper heat-resistant insulating pad 23 is arranged between the top of the cylindrical body 21 and the flange 225 of the top cover 22 in the up-down direction D. The upper heat-resistant insulating pad 23 includes an upper ring body 231 and a plurality of upper stack bodies 232. The upper ring body 231 has an upper flat surface 231a, an upper annular channel 231b, a lower flat surface 231c, and a central hole 231d. The upper flat surface 231a of the upper ring body 231 is attached to the bottom side plane 225a of the flange 225 of the top cover 22 so that the upper annular channel 231b of the upper ring body 231 and the annular air inlet groove 225b of the flange 225 are matched and closed. The upper annular channel 231b is recessed downward from the upper flat surface 231a. A plurality of communication holes 231b1 are provided on the bottom surface of the upper annular channel 231b. The central hole 231d communicates with the inner cavity 210 of the cylindrical body 21. The plurality of upper stack bodies 232 are arranged on the lower flat surface 231c of the upper ring body 231 and are spaced apart along the circumferential direction of the upper ring body 231. Each upper stack body 232 is provided with a radially open air outlet 232a. The air outlet 232a faces the inner cavity 210 of the cylindrical body 21 in the radial direction and the air outlet 232a communicates with the corresponding communication hole 231b1. Thus, the gas supplied externally is supplied into the inner cavity 210 of the cylindrical body 21 via the air inlet hole 224, the annular air inlet groove 225b, the upper annular channel 231b, the communication holes 231b1, the air outlet 232a, and the central hole 231d. The gas supplied into the inner cavity 210 of the cylindrical body 21 is ionized into plasma as the working gas. In addition, the gas supplied externally is supplied radially into the inner cavity 210 of the cylindrical body 21 from the air outlets 232a of the plurality of upper stack bodies 232 arranged at circumferential intervals. The gas supplied externally is supplied evenly and balancedly along the circumference of the upper ring body 231 into the inner cavity 210 of the cylindrical body 21. In this way, the raw materials supplied into the inner cavity 210 of the cylindrical body 21 via the feed pipe 10 are radially and evenly pushed inward by the gas supplied from the air outlets 232a. This radial inward push forms an effective stirring enhancement cooperation with the radial outward push generated by the expanded compressed gas in the middle that the raw materials have experienced before, so that the radially outer part of the raw materials moves radially inward and approaches the high temperature of the plasma arc, thereby making the overall heat exchange of the raw materials uniform, the melting balanced, and the powder amount formed by subsequent cooling uniform. In addition, this radial inward push also prevents the plasma arc or the drifting arc of the plasma arc from approaching the inner surface of the cylindrical body 21 to a certain extent. The material of the top cover 22 is preferably heat-conducting and heat-resistant. Of course, taking into account cost and availability, the top cover 22 can be made of a metal material, and the metal material can be stainless steel. It should be noted that the gas supplied externally and the compressed gas supplied via the jet nozzle 11 are the same gas.

[0097] The upper heat-resistant insulating pad 23 can be arranged between the top of the cylinder body 21 and the flange 225 of the top cover 22 in the up-and-down direction D through bolts, nuts with insulating means and corresponding screw holes. The number of the upper stack bodies 232 is the same as the number of the insulators 212. It should be noted that the number of the upper stack bodies 232 is shown as 12 in Figure 17 , but it is not limited to this, and it can be determined to be less than 12 or more than 12 according to needs. As Figure 17 shown, the air outlets 232a of each upper stack body 232 are multiple and arranged in a column in the up-and-down direction D. Of course, the air outlets 232a can be arranged in multiple columns. Like the insulators 212, the material of the upper heat-resistant insulating pad 23 is preferably heat-resistant and takes into account mechanical strength. For example, mica sheets can be used.

[0098] As Figures 9 to 13 shown, the cylinder body 21 includes a plurality of petal bodies 211 and a plurality of insulators 212 that are fixed together and enclose an inner cavity 210. The plurality of petal bodies 211 and the plurality of insulators 212 are alternately arranged along the circumferential direction of the cylinder body 21 so that there is one insulator 212 between two adjacent petal bodies 211. The inside of each petal body 211 is used for introducing a circulating cooling medium, and the inside of each insulator 212 is used for introducing a circulating cooling fluid.

[0099] Compared with the stainless-steel crucible in the prior art that adopts an integrally single-piece frustum of a cone or a cylinder, in the plasma arc powder preparation device 100 of the present disclosure, through the cylinder body 21 of a plurality of petal bodies 211 with a circulating cooling medium introduced into the inside thereof that are fixed together and enclose the inner cavity 210 and a plurality of insulators 212 with a circulating cooling fluid introduced into the inside thereof, the cylinder body 21 can withstand the high temperature of the plasma arc inside the cylinder body 21. The insulator 212 existing between two adjacent petal bodies 211 enables electrical insulation between adjacent petal bodies 211, avoiding the current of the drifting arc of the plasma arc from flowing through the inside of the adjacent petal bodies 211 in the circumferential direction and breaking down each petal body 211, eliminating the risk that the plasma arc or the drifting arc of the plasma arc contacts the cylinder body and then breaks through the cylinder body by flowing inside the cylinder body, and improving the working life and working stability of the cylinder body 21. The cooling medium and the cooling fluid can be the same or different. Preferably, the cooling medium is also an insulating material, so that the foregoing breakdown resistance performance can be further improved. For example, pure water is used. Using pure water not only realizes insulation but also can enhance the heat exchange capacity at the same time, thereby further improving the working life and working stability of the cylinder body 21. In addition, for the material of the petal body 211, the material is preferably heat-conducting and heat-resistant, and of course, it takes into account cost and availability. The petal body 211 can be made of a metal material, and the metal material can be stainless steel. The material of the insulator 212 is preferably heat-resistant and takes into account mechanical strength. For example, corundum or quartz can be used.

[0100] AsFigure 4 as shown and in combination with Figures 10 to 17 , the top surfaces of the multiple valve bodies 211 are coplanar and are in contact with the lower flat surface 231c of the upper ring body 231 of the upper heat-resistant insulating pad 23. The top surfaces of the respective insulators 212 are lower than the top surfaces of the adjacent two valve bodies 211, so that a receiving groove S is formed between the top surfaces of the adjacent two valve bodies 211 and the top surfaces of the insulators 212 between the adjacent two valve bodies 211. The receiving groove S is used for hermetically receiving a corresponding upper stack body 232. That is to say, the upper stack body 232 of the upper heat-resistant insulating pad 23 forms an insertion fit with the receiving groove S of the cylinder body 21 and forms an insulating extension with the insulator 212, which not only enhances the insulation between the adjacent two valve bodies 211 but also is beneficial to the positioning and assembly of the adjacent two valve bodies 211. Further, as Figure 11 and Figure 12 shown, each valve body 211 has an upper flat block 211a. The top surface of the upper flat block 211a is a horizontal plane. The top surfaces of the upper flat blocks 211a of the multiple valve bodies 211 are coplanar and are in contact with the lower flat surface 231c of the upper ring body 231 of the upper heat-resistant insulating pad 23. The top surfaces of the respective insulators 212 are lower than the top surfaces of the upper flat blocks 211a of the adjacent two valve bodies 211, so that the receiving groove S is formed between the top surfaces of the upper flat blocks 211a of the adjacent two valve bodies 211 and the top surfaces of the insulators 212 between the adjacent two valve bodies 211. Thus, it is beneficial to the overall structural compactness and overall strength after the assembly of the upper heat-resistant insulating pad 23 with the valve bodies 211 and the insulators 212 of the cylinder body 21.

[0101] In order to realize the assembly of the adjacent valve bodies 211 together with the corresponding insulators 212, as Figures 10 to 12 shown, each valve body 211 has two upper upright blocks 211b and two lower upright blocks 211c respectively located at the top and the bottom. Each upper upright block 211b has an upper through hole 211b1 penetrating in the circumferential direction, and each lower upright block 211c has a lower through hole 211c1 penetrating in the circumferential direction. The reactor 2 further includes a pair of upper bolts 24A and upper nuts 25A, lower bolts 24B and lower nuts 25B. The corresponding upper bolts 24A are insulated and pass through the upper through holes 211b1 of the adjacent upper upright blocks 211b of the adjacent valve bodies 211 and are threadedly connected with the corresponding upper nuts 25A to fixedly insulate the adjacent valve bodies 211 together in the circumferential direction. The corresponding lower bolts 24B are insulated and pass through the lower through holes 211c1 of the adjacent lower upright blocks 211c of the adjacent valve bodies 211 and are threadedly connected with the corresponding lower nuts 25B to fixedly insulate the adjacent valve bodies 211 together in the circumferential direction. The upper bolts 24A and upper nuts 25A and the lower bolts 24B and lower nuts 25B can be directly made of insulating materials to achieve insulation, or can be made of metal materials and then cooperate with insulating gaskets to achieve insulation, etc.

[0102] For the circulation of the cooling medium introduced into the interiors of the plurality of vane bodies 211 and the circulation of the cooling fluid introduced into the interiors of the plurality of insulators 212, as Figure 3 , Figure 6 , Figure 8 , Figure 9 , Figure 12 and Figure 13 shown, the reactor 2 further has an annular cylinder 26. The interior of the annular cylinder 26 is hollow, and the annular cylinder 26 surrounds the tops of the plurality of vane bodies 211 and the plurality of insulators 212 from the radially outer side; each vane body 211 has an upper pipe section 211d and a lower pipe section 211e at the top and bottom, and both the upper pipe section 211d and the lower pipe section 211e communicate with the interior of the corresponding vane body 211; each insulator 212 has an upper pipe joint 212a and a lower pipe joint 212b at the top and bottom, and both the upper pipe joint 212a and the lower pipe joint 212b communicate with the interior of the corresponding insulator 212; the upper pipe sections 211d of the plurality of vane bodies 211 and the upper pipe joints 212a of the plurality of insulators 212 are fixed and communicated with the annular cylinder 26; the cooling medium and the cooling fluid are the same fluid; the lower pipe sections 211e of the plurality of vane bodies 211 are used to connect to the externally cooled fluid, and the cooled fluid entering through the lower pipe sections 211e of the plurality of vane bodies 211 sequentially passes through the interiors of the plurality of vane bodies 211, the upper pipe sections 211d of the plurality of vane bodies 211, the interior of the annular cylinder 26, the upper pipe joints 212a of the plurality of insulators 212, the interiors of the plurality of insulators 212 and flows out through the lower pipe joints 212b of the plurality of insulators 212. The flowed-out and heat-exchanged fluid can be further used for additional heat recovery and recycled to the lower pipe sections 211e of the plurality of vane bodies 211.

[0103] To improve the convenience of assembly and fixation between the upper pipe sections 211d of the plurality of vane bodies 211 and the upper pipe joints 212a of the plurality of insulators 212 and the annular cylinder 26, as Figure 6 , Figures 8 to 10 shown, the reactor 2 further has a plurality of adapter pipes 27. The upper pipe section 211d of each vane body 211 is fixed and communicated with the annular cylinder 26 via a corresponding adapter pipe 27, and the upper pipe joint 212a of each insulator 212 is fixed and communicated with the annular cylinder 26 via a corresponding adapter pipe 27. In addition, the provision of the adapter pipes 27 also improves the structural stability and the overall structural strength of the vane bodies 211, the insulators 212 and the annular cylinder 26. Further, to improve the convenience of assembly, as Figure 6 shown, the upper pipe sections 211d of the plurality of vane bodies 211 and the upper pipe joints 212a of the plurality of insulators 212 are coplanar.

[0104] The materials of the positive electrode 3A and the negative electrode 3B can be selected from any suitable materials. For example, both the positive electrode 3A and the negative electrode 3B are graphite electrodes. The graphite electrode is a consumable electrode, suitable for the preparation of oxidized powders. Non-consumable electrodes such as tungsten electrodes can also be used, which are suitable for the preparation of non-oxidized powders. In order to make the ends of the positive electrode 3A and the negative electrode 3B easier to align, the positive electrode 3A and the negative electrode 3B can be inclined relative to each other. For example, the positive electrode 3A and the negative electrode 3B form an angle of 60 degrees. Of course, the positive electrode 3A and the negative electrode 3B need to be insulated from the top cover 22 of the reactor 2, and any suitable means can be used for insulation. The power of the DC plasma power supply connected to the positive electrode 3A and the negative electrode 3B is appropriately selected according to the particle size of the powder to be prepared, the production capacity to be achieved, the temperature reached by the plasma arc, the size of the plasma arc, etc.

[0105] Refer to Figures 1 to 6 , Figure 8 and Figure 21 and Figure 22, the plasma arc powder preparation device 100 may further include a magnetron 4. The magnetron 4 is provided with a cylindrical housing 41 and circumferentially alternating and spaced main magnetic poles 42 and auxiliary magnetic poles 43 provided on the inner wall of the cylindrical housing 41. The main magnetic poles 42 and the auxiliary magnetic poles 43 are radially located between the cylindrical housing 41 and the cylinder body 21 of the reactor 2 and are radially spaced from the cylinder body 21 of the reactor 2. The main magnetic poles 42 are connected to a DC plasma power supply to generate a rotating magnetic field that rotates the plasma arc, and the auxiliary magnetic poles 43 are connected to a three-phase AC power supply to generate a magnetic field that pushes the plasma arc radially inward. By forming a rotating magnetic field for the rotation of the plasma arc through the main magnetic poles 42, the action of the rotating magnetic field causes the arc formed between the positive electrode 3A and the negative electrode 3B to be constrained and elongated, and further makes the formed plasma arc become stable. The rotating plasma arc drives the raw materials to rotate, thereby enhancing the stirring and heat exchange effect on the raw materials, making the raw materials melt and gasify more uniformly, obtaining more consistent powder, and obtaining a more stable amount of powder. By generating a magnetic field that pushes the plasma arc radially inward through the auxiliary magnetic poles 43, similarly, this radial inward push forms an effective stirring enhancement cooperation with the previously described radial outward push generated by the expanding compressed gas in the middle on the raw materials, so that the part of the raw materials located radially outward moves radially inward and approaches the high temperature of the plasma arc, thereby making the overall heat exchange of the raw materials uniform, the melting balanced, and the particle size of the formed powder uniform. In addition, the magnetic field generated by the auxiliary magnetic poles 43 that pushes the plasma arc radially inward will prevent the plasma arc or the drifting arc of the plasma arc from approaching the inner wall surface of the cylinder body 21 (i.e., the surface of the lobe body 211 facing the inner cavity 210), avoiding the risk that the cylinder body 21 (i.e., the inner wall surface of the cylinder body 21) is ablated due to the contact of the plasma arc or the drifting arc of the plasma arc with the cylinder body 21, and further eliminating the risk that the plasma arc or the drifting arc of the plasma arc flows through and breaks through the cylinder body 21 in the cylinder body 21, thereby improving the working stability and working life of the reactor 2. From this perspective, the magnetic field generated by the auxiliary magnetic poles 43 that pushes the plasma arc radially inward also plays a role in stabilizing the plasma arc. In addition, based on avoiding the risk that the cylinder body 21 (i.e., the inner wall surface of the cylinder body 21) is ablated due to the contact of the plasma arc or the drifting arc of the plasma arc with the cylinder body 21, the pollution of the prepared powder caused by the material of the cylinder body 21 due to ablation of the cylinder body 21 is avoided, and the purity of the prepared powder is improved.

[0106] Specifically, as Figure 21 and Figure 22As shown, there are four main magnetic poles 42, and the four main magnetic poles 42 are distributed at 90-degree intervals. Each main magnetic pole 42 includes a first magnetic conductor 421 and a first winding 422. The first magnetic conductor 421 has an inner side surface 421a and a circumferential surface 421b. The normal direction of the inner side surface 421a faces the center of the cylindrical outer shell 41. The circumferential surface 421b is arranged around the normal direction of the inner side surface 421a and is disposed around the inner side surface 421a. The first winding 422 is spirally arranged around the circumferential surface 421b. Each pair of main magnetic poles 42 that are radially opposite form an N pole and an S pole. The N poles in the two pairs of main magnetic poles 42 are adjacent. The first windings 422 of each pair of main magnetic poles 42 that are radially opposite are connected in series. The first windings 422 of the two pairs of main magnetic poles 42 that are respectively connected in series are connected in parallel at the N poles and in parallel at the S poles and then connected in series in the circuit of the DC plasma power supply. The N poles connected in parallel are electrically connected to the positive electrode 3A, and the S poles connected in parallel are electrically connected to the negative electrode 3B; there are four auxiliary magnetic poles 43, and the four auxiliary magnetic poles 43 are alternately arranged with the four main magnetic poles 42. Each auxiliary magnetic pole 43 includes a second magnetic conductor 431 and a second winding 432. The second magnetic conductor 431 has an inner surface 431a and a circumferential surface 431b. The normal direction of the inner surface 431a faces the center of the cylindrical outer shell 41. The circumferential surface 431b is arranged around the normal direction of the inner surface 431a and is disposed around the inner surface 431a. The second winding 432 is spirally arranged around the circumferential surface 431b. The second windings 432 of each auxiliary magnetic pole 43 are connected to a three-phase AC power supply. Based on the fact that the four main magnetic poles 42 are distributed at 90-degree intervals and the four auxiliary magnetic poles 43 are alternately arranged with the four main magnetic poles 42, the four auxiliary magnetic poles 43 generate a magnetic field that radially pushes the plasma arc inward at four positions, so that the plasma arc is more uniformly pushed inward in the circumferential direction. The plasma arc drives the surrounding raw materials to be pushed inward as well, so that an effective stirring enhancement cooperation is formed with the radially outward push generated by the expanding compressed gas in the middle that the previous raw materials experienced. In addition, the magnetic field generated by the four auxiliary magnetic poles 43 that radially push the plasma arc inward at four positions will cause the plasma arc or the drifting arc of the plasma arc not to approach the inner wall surface of the cylinder 21 (i.e., the surface of the petal body 211 facing the inner cavity 210), playing a role in stabilizing the plasma arc, avoiding ablation of the inner wall surface of the cylinder 21 caused by contact with the plasma arc or the drifting arc of the plasma arc, thereby improving the working stability and working life of the reactor 2 and improving the purity of the prepared powder. The aforementioned magnetic conductor can be made of a suitable material, such as silicon steel sheets.

[0107] The cylindrical outer shell 41 of the magnetron 4 is sleeved outside the cylinder 21 of the reactor 2. The cylindrical outer shell 41 can be prepared from a metal material. In order to improve the structural integrity of the plasma arc powder preparation device 100, maintain the position stability of the cylindrical outer shell 41 relative to the cylinder 21 of the reactor 2, and further maintain the position stability of the main magnetic poles 42 and the auxiliary magnetic poles 43 relative to the cylinder 21 of the reactor 2, as Figure 3 、 Figures 8 to 12As shown, the valve body 211 further has an upper connection block 211f. The upper connection blocks 211f of the valve bodies 211 are located below the upper flat block 211a and are spaced apart from the upper flat block 211a in the up-down direction D. The lower surfaces of the upper connection blocks 211f of the multiple valve bodies 211 are coplanar. The magnetron 4 further includes an upper annular insulating member 44. The upper annular insulating member 44 is sleeved on the multiple valve bodies 211, and the upper annular insulating member 44 is fixed (for example, by screws with insulating means) between the top surface of the cylindrical housing 41 and the lower surface of the upper connection blocks 211f of the multiple valve bodies 211 in the up-down direction D. The upper annular insulating member 44 can be a mica sheet.

[0108] To improve the heat dissipation capacity of the magnetron 4, as Figure 3 、 Figure 6 、 Figure 8 and Figure 9 shown, the magnetron 4 further includes a lower annular insulating member 45 and an air inlet pipe 46. The lower annular insulating member 45 is sleeved on the bottom of the multiple valve bodies 211 and is spaced apart at a gap in the radial direction. The lower annular insulating member 45 is fixed (for example, by screws with insulating means) to the bottom surface of the cylindrical housing 41. One end of the air inlet pipe 46 communicates with the gap between the cylindrical housing 41 and the cylinder body 21 of the reactor 2, and the other end of the air inlet pipe 46 communicates with an external air supply device (not shown), so that the air sent out by the air supply device enters the gap between the cylindrical housing 41 and the cylinder body 21 of the reactor 2 through the air inlet pipe 46 and is discharged through the gap between the lower annular insulating member 45 and the bottom of the multiple valve bodies 211. The lower annular insulating member 45 provides insulation protection for the cylindrical housing 41 from below. The lower annular insulating member 45 can be a mica sheet.

[0109] To adjust the distance between the ends of the positive electrode 3A and the negative electrode 3B in real time, referring to Figures 1 to 13 and combining Figure 14 and Figure 15 , the plasma arc powder preparation device 100 further includes a positive electrode conveying mechanism 5A and a negative electrode conveying mechanism 5B. The positive electrode conveying mechanism 5A is used to enter the inner cavity 210 of the cylinder body 21 through the positive electrode hole 221 on the top cover 22 of the reactor 2 with the positive electrode 3A; the negative electrode conveying mechanism 5B is used to enter the inner cavity 210 of the cylinder body 21 through the negative electrode hole 222 on the top cover 22 of the reactor 2 with the negative electrode 3B; the positive electrode 3A and the negative electrode 3B respectively control the distance between the ends of the positive electrode 3A and the negative electrode 3B through the positive electrode conveying mechanism 5A and the negative electrode conveying mechanism 5B. By adopting the positive electrode conveying mechanism 5A and the negative electrode conveying mechanism 5B, flexible, precise and real-time adjustment of the distance between the ends of the positive electrode 3A and the negative electrode 3B is realized, and further, stable continuous operation of the plasma arc and continuous normal operation of the plasma arc powder preparation device 100 are maintained. The positive electrode conveying mechanism 5A and the negative electrode conveying mechanism 5B can adopt any suitable structure. For example, as Figure 2As shown, both the positive electrode conveying mechanism 5A and the negative electrode conveying mechanism 5B use a pair of rollers 41 for pinch feeding, and one of the rollers in the pair of rollers 41 can be active and the other can be driven.

[0110] Referring to Figures 1 to 3 , the plasma arc powder preparation device 100 further includes a settling chamber 6. The settling chamber 6 is connected to the bottom of the cylinder body 21 of the reactor 2, and is used to receive the vaporized raw materials and gases from the cylinder body 21, cool the vaporized raw materials into powders, and separate the powders and gases in the settling chamber 6 based on gravity. Through the setting of the settling chamber 6, the preparation of powders can be carried out continuously without being limited by the internal volume of the cylinder body 21, improving the production capacity of the plasma arc powder preparation device 100.

[0111] As Figure 2 and Figure 3 shown, the settling chamber 6 includes a top plate 61, a barrel body 62, and an exhaust pipe 63. The top plate 61 is connected to the lower end of the cylinder body 21 of the reactor 2 and closes the barrel body 62 from above. The inside of the barrel body 62 communicates with the inner cavity 210 of the cylinder body 21 of the reactor 2. The barrel body 62 can admit gases. The barrel body 62 is used for the powders formed in the inner cavity 210 to settle therein. The exhaust pipe 63 is connected to the top plate 61 of the settling chamber 6, and the exhaust pipe 63 is used for the gases in the settling chamber 6 to be discharged outwards. The gases discharged outwards can be connected to, for example, a cyclone separator (and even some filters and environmental dust collectors, etc.) to further separate and recover the powders mixed in the gases discharged outwards, thereby improving the powder yield.

[0112] As Figure 2 , Figure 5 , Figures 18 to 20, the settling chamber 6 further includes a connecting flange 64. The connecting flange 64 is disposed on the top plate 61 and communicates with the interior of the barrel 62. The connecting flange 64 has a top-side plane 641, an air inlet port 642, and a central through-hole 643 penetrating in the up-down direction D. An annular air inlet passage 641a is provided on the top-side plane 641. The annular air inlet passage 641a is recessed downward from the top-side plane 641 and communicates with the air inlet port 642. The air inlet port 642 is used to communicate with an external gas supply device (not shown). The central through-hole 643 communicates with the interior of the barrel 62. The reactor 2 further includes a lower heat-resistant insulating pad 28. The lower heat-resistant insulating pad 28 is disposed at the bottom of the cylindrical body 21 in the up-down direction D. The lower heat-resistant insulating pad 28 includes a lower ring body 281 and a plurality of lower stacks 282; the lower ring body 281 has a top flat surface 281a, a lower annular channel 281b, a bottom flat surface 281c, and a central hole 281d. The top flat surface 281a of the lower ring body 281 is attached to the top-side plane 641 of the connecting flange 64; the lower annular channel 281b of the lower ring body 281 cooperates with the annular air inlet passage 641a of the connecting flange 64 and is closed. The lower annular channel 281b is recessed upward from the bottom flat surface 281c, and a plurality of communication ports 281b1 are provided on the top surface of the lower annular channel 281b; the plurality of lower stacks 282 are disposed on the top flat surface 281a of the lower ring body 281 and are spaced apart along the circumference of the lower ring body 281. Each lower stack 282 is provided with a radially open exhaust port 282a. The exhaust port 282a faces the inner cavity 210 of the cylindrical body 21 in the radial direction and the exhaust port 282a communicates with the corresponding communication port 281b1. Thus, the gas supplied by the external gas supply device enters the central hole 281d of the lower ring body 281 of the lower heat-resistant insulating pad 28 via the air inlet port 642, the annular air inlet passage 641a, the lower annular channel 281b, the communication port 281b1, and the exhaust port 282a, and then passes through the central through-hole 643 of the connecting flange 64 and enters the interior of the barrel 62. The powder and gas from the inner cavity 210 enter the interior of the barrel 62 through the central hole 281d of the lower ring body 281 of the lower heat-resistant insulating pad 28 and the central through-hole 643 of the connecting flange 64. The gas supplied by the external gas supply device is uniformly and evenly supplied into the central hole 281d of the lower ring body 281 along the circumference of the lower ring body 281. On the one hand, the gas supplied by the external gas supply device is used to promote the gasified raw material passing through the central hole 281d of the lower ring body 281 of the lower heat-resistant insulating pad 28 to accelerate into the interior of the barrel 62. On the other hand, it promotes the gasified raw material to be uniformly and evenly further cooled to form powder. It should be noted that the gas supplied by the external gas supply device and the compressed gas supplied via the jet nozzle 11 are the same gas.

[0113] Similarly, the lower heat-resistant insulating pad 28 can be disposed at the bottom of the cylindrical body 21 in the up-down direction D by bolts, nuts with insulating means, and corresponding screw holes. The number of the lower stacks 282 is the same as the number of the insulators 212. It should be noted that the lower stacks 282 areFigure 19 Shown as 12 in number, but not limited thereto, and less than 12 or more than 12 can be determined according to needs. As Figure 19 shown, the exhaust ports 282a of each lower stack body 282 are multiple and arranged in a column along the up-and-down direction D. Of course, the exhaust ports 282a can be arranged in multiple columns. Similar to the upper heat-resistant insulating pad 23, the material of the lower heat-resistant insulating pad 28 is preferably heat-resistant and takes into account mechanical strength. For example, mica sheets can be used.

[0114] As Figures 10 to 12 and Figure 19 shown, the bottom surfaces of the multiple flap bodies 211 are coplanar and are in contact with the top flat surface 281a of the lower ring body 281 of the lower heat-resistant insulating pad 28. The bottom surface of each insulator 212 is higher than the bottom surfaces of two adjacent flap bodies 211, so that a receiving groove G is formed between the bottom surfaces of two adjacent flap bodies 211 and the bottom surface of the insulator 212 between the two adjacent flap bodies 211. The receiving groove G is used for hermetically receiving a corresponding lower stack body 282. That is to say, the lower stack body 282 of the lower heat-resistant insulating pad 28 forms a plug-in fit with the receiving groove G of the cylinder body 21 and forms an insulating extension with the insulator 212, which not only enhances the insulation between two adjacent flap bodies 211 but also is beneficial to the positioning and assembly of two adjacent flap bodies 211. Further, each flap body 211 has a lower flat lying block 211g, the bottom surface of the lower flat lying block 211g is a horizontal plane, the bottom surfaces of the lower flat lying blocks 211g of the multiple flap bodies 211 are coplanar and are in contact with the top flat surface 281a of the lower ring body 281 of the lower heat-resistant insulating pad 28; the bottom surface of each insulator 212 is higher than the bottom surfaces of the lower flat lying blocks 211g of two adjacent flap bodies 211, so that the receiving groove G is formed between the bottom surfaces of the lower flat lying blocks 211g of two adjacent flap bodies 211 and the bottom surface of the insulator 212 between the two adjacent flap bodies 211. Thereby, it is beneficial to the overall structural compactness and overall strength after the assembly of the lower heat-resistant insulating pad 28 with the flap bodies 211 and the insulators 212 of the cylinder body 21.

[0115] In order to further improve the cooling capacity of the barrel body 62 of the settling chamber 6, the settling chamber 6 further includes a first water inlet port 65A and a second water inlet port 65B. The barrel body 62 is a closed water-cooling jacket, the top of the barrel body 62 is a top plate 61, and the first water inlet port 65A and the second water inlet port 65B are communicated with the water-cooling jacket and are used for supplying cooling water.

[0116] To further improve the cooling capacity of the sedimentation chamber 6, the sedimentation chamber 6 further includes a plurality of ventilation units 66. The plurality of ventilation units 66 are arranged at intervals along the circumferential direction of the barrel body 62 on the outer wall of the barrel body 62. Each ventilation unit 66 includes a cylinder 661 and a plurality of air needles 662. The cylinder 661 is used to communicate with an external gas supply source. The plurality of air needles 662 are arranged in a column along the up and down direction D. One end of each air needle 662 communicates with the cylinder 661. Each air needle 662 penetrates the barrel body 62 in a sealed manner and the air outlet of each air needle 662 is exposed inside the barrel body 62. Preferably, as Figure 2 shown, the columnar air needles 662 of the plurality of ventilation units 66 surround the barrel body 62 so that the outlets of the air needles 662 are exposed tangentially to the inner side wall of the barrel body 62. In this way, the gas supplied by the columnar air needles 662 of the plurality of ventilation units 66 will form an annular flow flowing along the circumferential direction, so that the cooling speed of the powder in the barrel body 62, the speed of the gasified raw material cooling to form powder, and the separation speed from the gas can be increased. In Figure 2 , four ventilation units 66 (i.e., four columns of air needles 662) are arranged at 90-degree intervals. Of course, the number of ventilation units 66 can be less than four or more than four, which can be flexibly determined according to needs. The gas supplied by the cylinder 661 is the same gas as the gas supplied through the jet nozzle 11. That is to say, in the plasma arc powder preparation equipment 100, the compressed gas supplied through the jet nozzle 11, the externally supplied gas introduced through the air inlet hole 224 of the top cover 22 of the reactor 2, the gas supplied to the outside through the gas inlet port 642 of the connection flange 64 of the sedimentation chamber 6, and the gas supplied to the barrel body 62 through the plurality of ventilation units 66 of the sedimentation chamber 6 are the same gas, so that the gas atmosphere of the connected reactor 2 and sedimentation chamber 6 is consistent. As mentioned above, the specific type of gas can be selected according to whether the prepared powder is a non-oxidized powder or an oxidized powder.

[0117] Referring to Figures 1 to 3 , the plasma arc powder preparation equipment 100 further includes a material receiving bin 7. The material receiving bin 7 is arranged at the bottom of the sedimentation chamber 6 (the bottom of the barrel body 62 in the example in the figure) and is used to collect the powder sedimented through the sedimentation chamber 6.

[0118] Referring to Figure 2 , the plasma arc powder preparation equipment 100 further includes an observation window 8. The observation window 8 is arranged on the top cover 22 of the reactor 2 to facilitate manual inspection during the production process.

[0119] Referring to Figure 2 , the plasma arc powder preparation equipment 100 further includes a vision control sensor 9. The vision control sensor 9 is arranged on the top cover 22 of the reactor 2. The vision control sensor 9 is communicatively connected to the positive electrode conveying mechanism 5A and the negative electrode conveying mechanism 5B and is used to control the feeding distances of the positive electrode 3A and the negative electrode 3B respectively conveyed by the positive electrode conveying mechanism 5A and the negative electrode conveying mechanism 5B and the normal operation of the arc.

[0120] Multiple exemplary embodiments are described with the above detailed description, but the present disclosure is not intended to be limited to the explicitly disclosed combinations. Thus, unless otherwise stated, the various features disclosed herein may be combined together to form multiple additional combinations not shown for the sake of brevity.

Claims

1. A plasma arc powder preparation device, characterized in that, It includes a discharging mechanism (1), a reactor (2), a positive electrode (3A), a negative electrode (3B), and a magnetron (4). The discharging mechanism (1) is used to supply raw materials for preparing powder. The discharging mechanism (1) includes a feeding pipe (10) and a jet nozzle (11). The feeding pipe (10) is used to convey raw materials for preparing powder. The feeding pipe (10) is located between the positive electrode (3A) and the negative electrode (3B). The jet nozzle (11) enters the interior of the feeding pipe (10) from the outside and extends downward inside the feeding pipe (10) and is spaced apart from the inner wall of the feeding pipe (10). The jet nozzle (11) is used to supply compressed gas. The reactor (2) includes a cylinder body (21) and a top cover (22). The cylinder body (21) includes an inner cavity (210). The top cover (22) is provided with a feeding hole (223). The feeding hole (223) allows the feeding pipe (10) together with the jet nozzle (11) to be positioned there. The positive electrode (3A) and the negative electrode (3B) are used to connect to the circuit of a DC plasma power supply. The positive electrode (3A) and the negative electrode (3B) are used to extend into the inner cavity (210) of the cylinder body (21). The negative electrode (3B) and the positive electrode (3A) are used to form an arc between their ends and ionize the compressed gas supplied into the inner cavity (210) of the cylinder body (21) via the jet nozzle (11) into plasma to form a plasma arc. The magnetron (4) is provided with a cylindrical housing (41) and main magnetic poles (42) and auxiliary magnetic poles (43) that are circumferentially alternating and spaced apart on the inner wall of the cylindrical housing (41). The main magnetic poles (42) and the auxiliary magnetic poles (43) are radially located between the cylindrical housing (41) and the cylinder body (21) of the reactor (2) and are radially spaced apart from the cylinder body (21) of the reactor (2). The main magnetic poles (42) are connected to a DC plasma power supply to generate a rotating magnetic field that rotates the plasma arc. The auxiliary magnetic poles (43) are connected to a three-phase AC power supply to generate a magnetic field that radially pushes the plasma arc inward. There are four main magnetic poles (42). The four main magnetic poles (42) are distributed at 90-degree intervals. Each main magnetic pole (42) includes a first magnetic conductor (421) and a first winding (422). The first magnetic conductor (421) has an inner side surface (421a) and a circumferential surface (421b). The normal direction of the inner side surface (421a) faces the center of the cylindrical housing (41). The circumferential surface (421b) is arranged around the normal direction of the inner side surface (421a) around the inner side surface (421a). The first winding (422) is spirally arranged around the circumferential surface (421b). Each pair of main magnetic poles (42) that are radially opposite form an N pole and an S pole. The N poles in the two pairs of main magnetic poles (42) are adjacent. The first windings (422) of each pair of main magnetic poles (42) that are radially opposite are connected in series. The first windings (422) of the two pairs of main magnetic poles (42) that are respectively connected in series are connected in parallel with the N poles and in parallel with the S poles and then connected in series in the circuit of the DC plasma power supply. The N poles connected in parallel are electrically connected to the positive electrode (3A), and the S poles connected in parallel are electrically connected to the negative electrode (3B). There are four auxiliary magnetic poles (43), and the four auxiliary magnetic poles (43) are arranged alternately with the four main magnetic poles (42). Each auxiliary magnetic pole (43) includes a second magnetic conductor (431) and a second winding (432). The second magnetic conductor (431) has an inner surface (431a) and a circumferential surface (431b). The normal direction of the inner surface (431a) faces the center of the cylindrical housing (41). The circumferential surface (431b) is arranged around the normal direction of the inner surface (431a) and is disposed around the inner surface (431a). The second winding (432) is spirally arranged around the circumferential surface (431b). The second windings (432) of each auxiliary magnetic pole (43) are connected to a three-phase AC power supply.

2. The plasma arc powder preparation device according to claim 1, characterized in that The jet nozzle (11) penetrates into the interior of the feed pipe (10) and bends downward inside the feed pipe (10).

3. The plasma arc powder preparation device according to claim 2, characterized in that The feed pipe (10) includes an inverted cone barrel part (101) and a straight cylinder part (102) that communicate with each other. The inverted cone barrel part (101) is used to receive the raw materials for preparing the powder. The straight cylinder part (102) is connected to the inverted cone barrel part (101) from below. The lower end of the straight cylinder part (102) is positioned at the feed hole (223); The jet nozzle (11) includes an elbow part (111) and a nozzle part (112) that communicate with each other. The elbow part (111) penetrates into the inverted cone barrel part (101) of the feed pipe (10) and bends downward inside the inverted cone barrel part (101). The nozzle part (112) extends downward from the end of the elbow part (111) and centrally extends into the straight cylinder part (102).

4. The plasma arc powder preparation device according to claim 1, characterized in that The feed pipe (10) is in a standing state.

5. The plasma arc powder preparation device according to claim 1, characterized in that The top cover (22) of the reactor (2) is provided with an air inlet hole (224) and a flange (225). The air inlet hole (224) is used to access the externally supplied gas. The flange (225) has a bottom side plane (225a). An annular air inlet groove (225b) is provided on the bottom side plane (225a). The annular air inlet groove (225b) is recessed upward from the bottom side plane (225a) and communicates with the air inlet hole (224); The reactor (2) further includes an upper heat-resistant insulating pad (23). The upper heat-resistant insulating pad (23) is arranged between the top of the cylindrical body (21) and the flange (225) of the top cover (22) in the up-down direction (D). The upper heat-resistant insulating pad (23) includes an upper ring body (231) and a plurality of upper stack bodies (232). The upper ring body (231) has an upper flat surface (231a), an upper annular channel (231b), a lower flat surface (231c), and a central hole (231d). The upper flat surface (231a) of the upper ring body (231) is in contact with the bottom side plane (225a) of the flange (225) of the top cover (22) so that the upper annular channel (231b) of the upper ring body (231) and the annular intake air channel (225b) of the flange (225) are matched and closed. The upper annular channel (231b) is recessed downward from the upper flat surface (231a). A plurality of communication holes (231b1) are provided on the bottom surface of the upper annular channel (231b). The central hole (231d) is communicated with the inner cavity (210) of the cylinder body (21). A plurality of upper stack bodies (232) are arranged on the lower flat surface (231c) of the upper ring body (231) and are spaced apart along the circumferential direction of the upper ring body (231). Each upper stack body (232) is provided with a radially open air outlet (232a). The air outlet (232a) faces the inner cavity (210) of the cylinder body (21) in the radial direction and the air outlet (232a) is communicated with the corresponding communication hole (231b1).

6. The plasma arc powder preparation device according to claim 1, wherein The cylinder body (21) includes a plurality of valve bodies (211) and a plurality of insulators (212) that are fixed together and enclose an inner cavity (210). The plurality of valve bodies (211) and the plurality of insulators (212) are alternately arranged along the circumferential direction of the cylinder body (21) so that there is an insulator (212) between two adjacent valve bodies (211). A circulating cooling medium is used to be introduced into the interior of each valve body (211), and a circulating cooling fluid is used to be introduced into the interior of each insulator (212).

7. The plasma arc powder preparation device according to claim 6, wherein, Both the cooling medium and the cooling fluid are pure water.

8. The plasma arc powder preparation device according to claim 6, wherein The reactor (2) further has an annular cylinder (26). The interior of the annular cylinder (26) is hollow. The annular cylinder (26) surrounds the tops of the plurality of valve bodies (211) and the plurality of insulators (212) from the radial outside. Each valve body (211) has an upper pipe section (211d) and a lower pipe section (211e) located at the top and the bottom. The upper pipe section (211d) and the lower pipe section (211e) are both communicated with the interior of the corresponding valve body (211). Each insulator (212) has an upper pipe joint (212a) and a lower pipe joint (212b) located at the top and the bottom. The upper pipe joint (212a) and the lower pipe joint (212b) are both communicated with the interior of the corresponding insulator (212). The upper pipe sections (211d) of the plurality of valve bodies (211) and the upper pipe joints (212a) of the plurality of insulators (212) are fixed and communicated with the annular cylinder (26). The cooling medium and the cooling fluid are the same fluid. The lower pipe sections (211e) of the multiple valve bodies (211) are used to access the externally cooled fluid. The cooled fluid entering through the lower pipe sections (211e) of the multiple valve bodies (211) sequentially passes through the interiors of the multiple valve bodies (211), the upper pipe sections (211d) of the multiple valve bodies (211), the interior of the annular cylinder (26), the upper pipe joints (212a) of the multiple insulators (212), the interiors of the multiple insulators (212), and flows out through the lower pipe joints (212b) of the multiple insulators (212).

9. The plasma arc powder preparation device according to claim 1, characterized in that The top cover (22) is provided with a positive electrode hole (221) and a negative electrode hole (222); The positive electrode (3A) and the negative electrode (3B) respectively extend into the inner cavity (210) of the cylinder body (21) through the positive electrode hole (221) and the negative electrode hole (222).

10. The plasma arc powder preparation device according to claim 9, characterized in that The plasma arc powder preparation device further includes a positive electrode conveying mechanism (5A) and a negative electrode conveying mechanism (5B), The positive electrode conveying mechanism (5A) is used to enter the positive electrode (3A) into the inner cavity (210) of the cylinder body (21) through the positive electrode hole (221) of the top cover (22) of the reactor (2); The negative electrode conveying mechanism (5B) is used to enter the negative electrode (3B) into the inner cavity (210) of the cylinder body (21) through the negative electrode hole (222) of the top cover (22) of the reactor (2); The positive electrode (3A) and the negative electrode (3B) respectively control the distance between the ends of the positive electrode (3A) and the negative electrode (3B) through the positive electrode conveying mechanism (5A) and the negative electrode conveying mechanism (5B).

11. The plasma arc powder preparation device according to claim 1, characterized in that, The plasma arc powder preparation device (100) further includes a sedimentation chamber (6). The sedimentation chamber (6) is connected to the bottom of the cylinder body (21) of the reactor (2) and is used to receive the vaporized raw materials and gases from the cylinder body (21), cool the vaporized raw materials into powders, and separate the powders and gases in the sedimentation chamber (6) based on gravity.

12. The plasma arc powder preparation device (100) according to claim 11, characterized in that The sedimentation chamber (6) includes a top plate (61), a barrel body (62), and an exhaust pipe (63). The top plate (61) is connected to the bottom of the cylinder body (21) of the reactor (2) and closes the barrel body (62) from above. The interior of the barrel body (62) communicates with the inner cavity (210) of the cylinder body (21) of the reactor (2). The barrel body (62) can admit gases. The barrel body (62) is used for the powders formed in the inner cavity (210) to settle therein. The exhaust pipe (63) is connected to the top plate (61) of the sedimentation chamber (6), and the exhaust pipe (63) is used for the gases in the sedimentation chamber (6) to be discharged outwards.

13. The plasma arc powder preparation device according to claim 12, wherein The settling chamber (6) includes a connecting flange (64). The connecting flange (64) is disposed on the top plate (61) and communicates with the interior of the barrel (62). The connecting flange (64) has a top-side plane (641), an air inlet port (642), and a central perforation (643) that penetrates in the up-down direction (D). An annular air inlet passage (641a) is provided on the top-side plane (641). The annular air inlet passage (641a) is recessed downward from the top-side plane (641) and communicates with the air inlet port (642). The air inlet port (642) is used to communicate with an external air supply device. The central perforation (643) communicates with the interior of the barrel (62). The reactor (2) further includes a lower heat-resistant insulating pad (28). The lower heat-resistant insulating pad (28) is disposed at the bottom of the cylindrical body (21) in the up-down direction (D). The lower heat-resistant insulating pad (28) includes a lower ring body (281) and a plurality of lower stack bodies (282). The lower ring body (281) has a top flat surface (281a), a lower annular channel (281b), a bottom flat surface (281c), and a central hole (281d). The top flat surface (281a) of the lower ring body (281) is in contact with the top-side plane (641) of the connecting flange (64). The lower annular channel (281b) of the lower ring body (281) cooperates with the annular air inlet passage (641a) of the connecting flange (64) and is closed. The lower annular channel (281b) is recessed upward from the bottom flat surface (281c). A plurality of communication ports (281b1) are provided on the top surface of the lower annular channel (281b). A plurality of lower stack bodies (282) are disposed on the top flat surface (281a) of the lower ring body (281) and are spaced apart along the circumferential direction of the lower ring body (281). Each lower stack body (282) is provided with a radially open exhaust port (282a). The exhaust port (282a) faces the inner cavity (210) of the cylindrical body (21) in the radial direction and the exhaust port (282a) communicates with the corresponding communication port (281b1).

14. The plasma arc powder preparation device according to claim 12, wherein The settling chamber (6) further includes a first water inlet port (65A) and a second water inlet port (65B). The barrel (62) is a closed water-cooled jacket. The top of the barrel (62) is the top plate (61). The first water inlet port (65A) and the second water inlet port (65B) communicate with the water-cooled jacket and are used for introducing cooling water.

15. The plasma arc powder preparation device according to claim 12, wherein The settling chamber (6) further includes a plurality of ventilation units (66). The plurality of ventilation units (66) are spaced apart along the circumferential direction of the barrel (62) and are disposed on the outer wall of the barrel (62). Each ventilation unit (66) includes a cylinder (661) and a plurality of air needles (662). The cylinder (661) is used to communicate with an external gas supply source. The plurality of air needles (662) are arranged in a column in the up-down direction (D). One end of each air needle (662) communicates with the cylinder (661). Each air needle (662) seals through the barrel (62) and the air outlet of each air needle (662) is exposed inside the barrel (62).

16. The plasma arc powder preparation device according to claim 15, characterized in that, The gas needles (662) of the multiple ventilation units (66) in a row are arranged around the barrel body (62), and the outlets of the gas needles (662) are exposed tangentially to the inner side wall of the barrel body (62).

17. The plasma arc powder preparation device according to claim 11, characterized in that The plasma arc powder preparation device (100) further includes a powder collection bin (7), and the powder collection bin (7) is arranged at the bottom of the sedimentation chamber (6) for collecting the powder sedimented through the sedimentation chamber (6).

18. The plasma arc powder preparation device according to claim 10, characterized in that The plasma arc powder preparation device (100) further includes a vision control sensor (9), and the vision control sensor (9) is arranged on the top cover (22) of the reactor (2). The vision control sensor (9) is communicatively connected to the positive electrode conveying mechanism (5A) and the negative electrode conveying mechanism (5B), and is used to control the feeding distances of the positive electrode (3A) and the negative electrode (3B) respectively conveyed by the positive electrode conveying mechanism (5A) and the negative electrode conveying mechanism (5B) and the normal operation of the arc.

Images