A plasma torch

Abstract

This utility model discloses a plasma torch, comprising a coaxially arranged intermediate tube and a water-cooled outer tube, with an annular cooling channel formed between the inner wall of the water-cooled outer tube and the outer wall of the intermediate tube; an insulating end cap disposed at the tail end of the intermediate tube for fixing a cathode assembly, and a cathode inner tube fixedly installed inside the insulating end cap, with a cathode head installed at the end of the cathode inner tube; a polytetrafluoroethylene (PTFE) insulating component fitted outside the cathode inner tube for electrical isolation; an air inlet assembly disposed outside the cathode inner tube communicating with a swirling channel disposed on the outer wall of the cathode inner tube near the cathode head, forming a swirling flow around the cathode head when air is supplied. The annular cooling channel effectively removes the heat generated during operation, preventing damage to the torch body due to high temperature; the PTFE insulating component ensures the reliability of electrical isolation; the formation of the swirling flow makes the gas distribution around the cathode head more uniform, which is beneficial for stable discharge and thus ensures stable plasma generation.

Description

Technical Field

[0001] This utility model relates to the field of plasma torch power supply technology, and in particular to a plasma torch. Background Technology

[0002] A plasma torch is a device that generates high-temperature gas through an electric arc. It can operate in oxidizing, reducing, or inert environments and can provide a heat source for various industrial furnaces. Based on the principle of the plasma state of matter, a plasma torch generates an electric arc by high-pressure breakdown of gas, forming a high-temperature plasma jet (temperatures exceeding 5500℃). It was used for aerospace testing abroad in the 1960s and later expanded to fields such as solid waste treatment; experimental facilities have also been built in China. During operation, the electric arc forms between electrodes, and is protected from ablation by rotating with a magnetic field; various arc ignition methods are available.

[0003] Plasma torches have advantages such as high temperature and high energy density, and are used in cutting, smelting and other applications. However, they also have problems such as short lifespan of traditional cathodes, high maintenance costs, insufficient energy efficiency of small devices, difficulty in studying internal multi-field coupling, and limited large-scale applications. Utility Model Content

[0004] In view of the problems in the prior art, the purpose of this utility model is to overcome the shortcomings of the prior art and provide a plasma torch.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a plasma torch. The device includes a coaxially arranged intermediate tube and a water-cooled outer tube, with an annular cooling water channel formed between the inner wall of the water-cooled outer tube and the outer wall of the intermediate tube; an insulating end cap located at the tail end of the intermediate tube for fixing the cathode assembly, and an inner cathode tube fixedly installed inside the insulating end cap, with a cathode head installed at the end of the inner cathode tube; a polytetrafluoroethylene insulating component fitted around the outer side of the inner cathode tube for electrical isolation; an air intake assembly located outside the inner cathode tube communicating with a swirling channel located on the outer wall of the inner cathode tube near the cathode head, forming a swirling flow around the cathode head when air is supplied; and an anode head located at the front end inside the water-cooled outer tube, forming a discharge gap with the cathode head.

[0006] The beneficial effects of this utility model are: (1) The plasma torch described in this utility model has a compact and reasonable overall structure design. The annular cooling water channel can effectively remove the heat generated during the operation and prevent the torch body from being damaged due to high temperature. The setting of polytetrafluoroethylene insulation parts ensures the reliability of electrical isolation. The formation of swirling flow makes the gas more evenly distributed around the cathode head, which is conducive to stable discharge and thus ensures the stable generation of plasma.

[0007] (2) The plasma torch described in this utility model is designed specifically for laboratories and small devices. It uses air or nitrogen as the working fluid, outputs a 3-5 kW DC non-transfer arc, and is small in size, fast in response, and has zero consumable gas cost. It can be applied to the surface remelting and deburring of 3D printed metal parts, small-scale melting and solidification of laboratory waste salt / ash, and seed layer cleaning of micro plasma chemical vapor deposition (MPCVD). Attached Figure Description

[0008] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0009] Figure 1 This is a schematic diagram of the overall structure of a preferred embodiment of a plasma torch provided by this utility model; Figure 2 for Figure 1 A sectional view; Figure 3 for Figure 2 Enlarged structural diagram of the connection between the cathode head and the inner cathode tube; Figure 4 This is a schematic diagram of the three-dimensional structure of the anode head; Figure 5 This is a schematic diagram of the three-dimensional structure of the cathode head; Figure label: 100. Intermediate tube; 110. Inner cathode tube; 111. Swirl channel; 120. PTFE insulation component; 200. Water-cooled outer tube; 210. Cooling water channel; 300. Lug; 400. Water inlet head; 410. Water inlet pipe; 500. Intake assembly; 510. Intake connector; 520. Intake pipe; 600. Water outlet component; 610. Water outlet connector; 620. Water outlet pipe; 700, Insulating end cap; 800, Anode head; 900, Cathode head. Detailed Implementation

[0010] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0011] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0012] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0013] like Figures 1-5 As shown, this utility model describes a plasma torch. It includes a coaxially arranged intermediate tube 100 and a water-cooled outer tube 200, wherein an annular cooling water channel 210 is formed between the inner wall of the water-cooled outer tube 200 and the outer wall of the intermediate tube 100; An insulating end cap 700 is provided at the tail end of the intermediate tube 100 for fixing the cathode assembly, and an inner cathode tube 110 is fixedly installed inside the insulating end cap 700. A cathode head 900 is installed at the end of the inner cathode tube 110. The polytetrafluoroethylene insulating component 120, which is fitted onto the outside of the cathode inner tube 110, is used for electrical isolation; The air intake assembly 500, which is disposed outside the cathode inner tube 110, is connected to the vortex channel 111 disposed on the outer wall of the cathode inner tube 110 near the cathode head 900. When air is supplied, it forms a vortex around the cathode head 900. The anode head 800 is located at the front end of the water-cooled outer tube 200, forming a discharge gap with the cathode head 900.

[0014] The intermediate tube 100 and the water-cooled outer tube 200 are coaxially arranged, and the annular cooling water channel 210 formed between them can cool the torch body; the insulating end cap 700 fixes the cathode inner tube 110, and the cathode head 900 is installed at the end of the cathode inner tube 110 fixed inside it. The polytetrafluoroethylene insulating part 120 sleeved on the outside of the cathode inner tube 110 achieves electrical isolation; the gas introduced by the air intake assembly 500 is connected through the swirling channel 111 with the outer wall of the cathode inner tube 110 near the cathode head 900. When the gas is introduced, a swirling flow is formed around the cathode head 900; the cathode head 900 and the anode head 800 located at the front end of the water-cooled outer tube 200 form a discharge gap. In the swirling gas environment, a discharge is generated at the discharge gap, thereby forming plasma.

[0015] The overall structure is compact and reasonable. The annular cooling water channel 210 can effectively remove the heat generated during operation and prevent the torch body from being damaged by high temperature. The setting of polytetrafluoroethylene insulation component 120 ensures the reliability of electrical isolation. The formation of swirling flow makes the gas more evenly distributed around the cathode head 900, which is conducive to stable discharge and thus ensures stable plasma generation.

[0016] In one embodiment, the inlet head 400 and the outlet part 600 of the water-cooled outer pipe 200 are connected to the cooling water channel 210 through the inlet pipe 410 and the outlet pipe 620, respectively. A water outlet connector 610 is provided at the end of the water outlet pipe 620.

[0017] In one embodiment, the working gas is air or nitrogen.

[0018] Using air and nitrogen as working fluids, eliminating the need for argon, hydrogen, etc., it reduces the production, transportation, and storage of special gases. Its green and environmentally friendly operation mode meets the needs of modern scientific research and production for low-carbon and sustainable development, and is also safer and more environmentally friendly.

[0019] The plasma torch is extremely small, weighing approximately 0.65 kg, making it compact and lightweight. This allows it to flexibly adapt to scenarios with high requirements for equipment size and operational flexibility, such as micro-area melting and surface decontamination. Whether it's localized processing in precision experiments or operations in confined spaces, it can easily handle the demands, greatly facilitating delicate operations. The plasma torch is plug-and-play, featuring a convenient connector design. In a laboratory setting, deployment and operation can be completed in just 5 minutes, significantly reducing preparation time before equipment startup and enabling researchers to conduct experiments more quickly, greatly improving operational convenience.

[0020] In one embodiment, the anode head 800 is made of T2 copper and also serves as a plasma jet nozzle. The cathode head 900 is a rod-shaped or bullet-shaped tungsten electrode with a hafnium emitter embedded at its discharge end.

[0021] The anode head 800 of the plasma torch is made of T2 copper and also serves as a nozzle, forming the torch's outlet. Its main function is electron collection and current circuitry, receiving electrons from the cathode to complete the current circuit and maintain the arc discharge. The anode arc root moves and jumps at high speed along the inner wall of the nozzle under the action of the airflow, avoiding localized overheating and reducing anode losses. After the plasma jet is formed, the arc is compressed and accelerated by the high-speed airflow within the anode nozzle, forming a high-temperature, high-speed plasma jet.

[0022] The plasma torch cathode head 900 is located at the center of the torch body and is a rod-shaped or bullet-shaped tungsten electrode. Its main function is as an electron emission source; upon energization, it emits thermionic electrons, generating a high-density electron beam that forms the arc root (cathode arc root). Under the action of a high-swirling airflow, the arc root of the cathode head 900 is stably constrained at the front end of the cathode center, ensuring a fixed arc initiation point and reducing cathode ablation. After connecting the high-frequency DC power supply, followed by compressed air and deionized water, and then turning on the external water pump to ensure the flow rate is within the preset range, the externally controlled ignition button is activated. After adjusting the power to the required value, the plasma torch uses a high-frequency, high-voltage pulse to instantaneously break down the gas between the cathode head 900 and the anode head 800, establishing a stable and continuous arc channel, rapidly heating the working gas into a high-temperature plasma jet. Using air as the sole working fluid, it provides a 3-5 kW DC non-transfer arc output, is small in size, has a fast response, and zero consumable gas costs.

[0023] The plasma torch is safe to use, automatically extinguishing the arc within 10ms in case of water shortage, gas shortage, or overheating, without damaging the torch and preventing dangerous situations from occurring at the source. More importantly, this instant protection design will not cause any damage to the torch body, ensuring operational safety while effectively maintaining the stability and lifespan of the equipment, making experimental operations more worry-free and reliable.

[0024] In one embodiment, the intermediate tube 100 is externally fixedly connected to an ear seat 300 for connection with a fixing frame.

[0025] The ear seat 300, which is fixedly connected to the outside of the intermediate tube 100, can be connected to the fixed frame. Through the cooperation between the ear seat 300 and the fixed frame, the plasma torch can be fixed in the required position.

[0026] The ear mount 300 provides a convenient way to install and fix the plasma torch, allowing it to be securely mounted on the mounting bracket. This prevents the plasma generation and usage effect from being affected by shaking during operation, and improves the stability of equipment operation.

[0027] In one embodiment, the air intake assembly 500 includes an air intake pipe 520, which is connected to the outer wall of the intermediate pipe 100 and communicates with the swirl channel 111. One end of the air pipe 520 located outside the intermediate pipe 100 is connected to an air intake connector 510.

[0028] The intake pipe 520 in the intake assembly 500 is connected to the outer wall of the intermediate pipe 100 and communicates with the swirling channel 111. Gas enters the intake pipe 520 through the intake connector 510 and is then transported to the swirling channel 111 through the intake pipe 520 to provide a gas source for plasma generation.

[0029] The structure of the air intake assembly 500 and the gas delivery path were clearly defined, ensuring that the gas could enter the vortex channel 111 stably and smoothly. This ensured a continuous gas supply during the formation of the vortex and the generation of plasma, improving the reliability of the plasma torch operation. Under the action of the high-vortex airflow, the cathode arc root was stably constrained at the front end of the cathode center, ensuring that the arc initiation point was fixed and reducing cathode ablation.

[0030] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0031] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The descriptions of the above embodiments and specifications are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection claimed by this utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A plasma torch, characterized in that: It includes a coaxially arranged intermediate tube and a water-cooled outer tube, wherein an annular cooling water channel is formed between the inner wall of the water-cooled outer tube and the outer wall of the intermediate tube; An insulating end cap is installed at the tail end of the intermediate tube to fix the cathode assembly, and an inner cathode tube is fixedly installed inside the insulating end cap, with a cathode head installed at the end of the inner cathode tube. A polytetrafluoroethylene (PTFE) insulating component fitted around the outside of the inner cathode tube is used for electrical isolation; The air intake assembly, located outside the inner tube of the cathode, is connected to the swirling channel located on the outer wall of the inner tube near the cathode head. When air is supplied, a swirling flow is formed around the cathode head. The anode head is located at the front end of the water-cooled outer tube, forming a discharge gap with the cathode head.

2. The plasma torch according to claim 1, characterized in that: The inlet and outlet of the water-cooled outer tube are connected to the cooling water channel through the inlet and outlet pipes, respectively. A water outlet connector is provided at the end of the water outlet pipe.

3. A plasma torch according to claim 1, characterized in that: The anode head is made of T2 copper and also serves as a plasma jet nozzle.

4. A plasma torch according to claim 1, characterized in that: The cathode head is a rod-shaped or bullet-shaped tungsten electrode, and a hafnium emitter is embedded in its discharge end.

5. A plasma torch according to claim 4, characterized in that: The intermediate tube is externally fixedly connected with lugs for connecting to the fixing frame.

6. A plasma torch according to claim 1, characterized in that: The air intake assembly includes an air intake pipe connected to the outer wall of the intermediate pipe and communicating with the vortex channel. One end of the air intake pipe, located outside the intermediate pipe, is connected to an air intake connector.

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