Cathode head for plasma device

Abstract

The present invention belongs to the technical field of plasma torches, and relates to a cathode head for a plasma device, comprising a cathode head body, which comprises an arc-starting emitter, an intermediate cylinder, a tail cylinder and a connection part for abutting against a plasma torch water-cooling pipe connected in sequence from left to right; the arc-starting emitter is made of tungsten or a tungsten alloy, and is formed integrally by an arc-starting cylinder and an arc-starting spherical segment, and one end of the arc-starting cylinder is fixed to one end of the intermediate cylinder; a threaded hole is provided in the intermediate cylinder, and an angle γ exists between the straight line where the hole wall of the threaded hole is located and the vertical direction, and the degree of the angle γ is 90° to 120°; an inclination angle ε is set at the connection end of the plasma torch water-cooling pipe, and the inclined surface where the inclination angle ε is located abuts against the threaded hole, so as to realize the hard sealing between the cathode head body and the plasma torch water-cooling pipe. The present invention improves the cathode head structure, has a good water cooling effect while having a compression arc function, and prolongs the service life of the cathode head.

Description

Technical Field

[0001] The invention belongs to the technical field of plasma torches and relates to a cathode head used for a plasma device. Background Art

[0002] The plasma torch is a device that produces high-temperature plasma and has been widely used in high-temperature heat sources. Its structure includes cathode components, anode components, water cooling system, gas system, etc. The center hole of the nozzle at the front end of the cathode head is the plasma arc channel. The internal high-temperature plasma relies on the water cooling of the inner wall of the anode and the water cooling of the cathode head to transfer heat to the nozzle and the water flow inside the cathode head.

[0003] In the above structure, the cathode head in the cathode component is the core component of arc initiation. Its relatively harsh working environment makes it a vulnerable part in the entire system structure, and its service life directly affects the working efficiency and operating cost of the plasma torch. The existing cathode head structure, although it can compress the arc to a certain extent, is prone to discharge in the non-discharge area during high-frequency arc initiation, resulting in ablation and reducing the service life of the cathode head; and the cooling water is prone to eddy currents, and the heat is not taken away in time, reducing the water cooling effect.

[0004] To this end, the present invention provides a novel cathode head for a plasma device to solve the above technical problems. Summary of the invention

[0005] The object of the present invention is to overcome the above-mentioned disadvantages of the prior art and provide a cathode head for a plasma device.

[0006] The purpose of the present invention is to be solved by the following technical solutions:

[0007] The cathode head for a plasma device comprises a cathode head body, which comprises an arc-starting emitter, an intermediate cylinder, a tail cylinder and a connecting portion for abutting against a water-cooling tube of a plasma torch, which are connected in sequence from left to right; the arc-starting emitter is made of tungsten or a tungsten alloy, and is integrally formed by an arc-starting cylinder and an arc-starting spherical segment, and one end of the arc-starting cylinder is fixed to one end of the intermediate cylinder; a threaded hole is provided in the intermediate cylinder, and an angle γ is formed between a straight line where a hole wall of the threaded hole is located and a vertical direction, and the degree of the angle γ is 90° to 120°; an inclination angle ε is set at the connecting end of the water-cooling tube of the plasma torch, and the inclined surface where the inclination angle ε is located abuts against the threaded hole, so as to realize a hard seal between the cathode head body and the water-cooling tube of the plasma torch.

[0008] Furthermore, one end of the arc-striking cylinder is fixedly welded to one end of the middle cylinder.

[0009] Furthermore, there is a transition angle α between the arc-starting cylinder and the intermediate cylinder, and the degree of the transition angle α is 60° to 90°.

[0010] Furthermore, a clamping structure for easy disassembly and assembly is provided on the outer side of one end where the middle cylinder is connected to the tail cylinder.

[0011] Furthermore, the clamping structure is an outer hexagonal structure.

[0012] Furthermore, there is a transition angle δ between the left end of the outer hexagonal structure and the middle cylinder, and the degree of the transition chamfer δ is 110° to 150°.

[0013] Furthermore, a transition angle β is provided on the left end surface of the tail cylinder, and the degree of the transition angle β is 30°-60°.

[0014] Furthermore, the inclination angle ε is in the range of 30°-60°.

[0015] Furthermore, the diameter of the arc-starting emitter is 8 to 18 mm.

[0016] Furthermore, the intermediate cylinder is made of pure copper or copper-based alloy and has a diameter of 20 to 30 mm.

[0017] Compared with the prior art, the technical solution provided by the present invention includes the following beneficial effects: by improving the structure of the cathode head, specifically: the arc-starting emitter is formed by an arc-starting cylinder and an arc-starting spherical segment in one piece, and the arc-starting emitter is made of tungsten or a tungsten alloy. Since the tungsten alloy has an extremely high melting point and excellent high temperature resistance, the outer surface of the arc-starting emitter is not easily burned by the arc flame flow to form a pit during operation, thereby enhancing the service life of the cathode head. At the same time, the design of the threaded hole reduces the use of materials while reducing the accumulation of heat in the cathode head, increasing the heat dissipation area and improving the cooling effect; and the angle γ between the straight line where the hole wall of the threaded hole is located and the vertical direction is matched with the inclination angle ε of the connecting end of the plasma torch water cooling pipe, and the inclined surface where the inclination angle ε is located abuts against the threaded hole, so as to realize the hard seal between the cathode head body and the plasma torch water cooling pipe, which can meet the sealing requirements under high water pressure environment.

[0018] In addition, the cathode head can be easily disassembled and installed by using a wrench in combination with the external hexagonal structure; the middle cylinder is made of pure copper or copper-based alloy, which can effectively dissipate the heat accumulated in the cathode head and extend the service life of the cathode head; the transition angle α between the arc-starting cylinder and the middle cylinder, the transition angle β set on the left end face of the tail cylinder, and the transition angle δ between the left end of the external hexagonal structure and the middle cylinder are mutually coordinated, which is conducive to the generation and concentration of the plasma jet on the cathode head. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the present invention.

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0021] Figure 1 The figure is an external structural diagram of a cathode head for a plasma device of the present invention;

[0022] Figure 2 for Figure 1 sectional view of

[0023] Figure 3 The present invention is a schematic structural diagram of the cathode head and nozzle used in a plasma device in cooperation with each other.

[0024] Among them: 1. arc-starting emitter; 2. middle cylinder; 3. tail cylinder; 4. connecting part; 5. threaded hole; 6. plasma torch water cooling tube; 7. outer hexagonal structure; α, transition angle between the arc-starting cylinder and the middle cylinder; β, transition angle set at the left end face of the tail cylinder; γ, angle between the straight line where the hole wall of the threaded hole is located and the vertical direction; δ, transition angle between the left end of the outer hexagonal structure and the middle cylinder; ε, inclination angle. DETAILED DESCRIPTION

[0025] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices consistent with some aspects of the present invention as detailed in the appended claims.

[0026] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0027] See also Figure 1-3As shown, the present invention provides a cathode head for a plasma device, including a cathode head body, wherein the cathode head body includes an arc-striking emitter 1, an intermediate cylinder 2, a tail cylinder 3 and a connecting portion 4 for abutting against a plasma torch water-cooling tube 6, which are connected in sequence from left to right; the arc-striking emitter 1 is made of tungsten or a tungsten alloy, and is integrally formed by an arc-striking cylinder and an arc-striking spherical segment, and one end of the arc-striking cylinder is fixed to one end of the intermediate cylinder 2; a threaded hole 5 is provided in the intermediate cylinder 2, and an angle γ is formed between the straight line where the hole wall of the threaded hole 5 is located and the vertical direction, and the degree of the angle γ is 90° to 120°; an inclination angle ε is set at the connecting end of the plasma torch water-cooling tube 6, and the inclined surface where the inclination angle ε is located abuts against the threaded hole 5, so as to realize a hard seal between the cathode head body and the plasma torch water-cooling tube 6.

[0028] Furthermore, one end of the arc-striking cylinder is fixedly welded to one end of the middle cylinder 2 .

[0029] Furthermore, there is a transition angle α between the arc-starting cylinder and the intermediate cylinder, and the degree of the transition angle α is 60° to 90°.

[0030] Furthermore, a snap-fit ​​structure for easy assembly and disassembly is provided on the outer side of one end where the middle cylinder 2 is connected to the tail cylinder 3 .

[0031] Furthermore, the clamping structure is an outer hexagonal structure 7.

[0032] Furthermore, there is a transition angle δ between the left end of the outer hexagonal structure 7 and the middle cylinder 2, and the degree of the transition chamfer δ is 110° to 150°.

[0033] Furthermore, a transition angle β is provided on the left end surface of the tail cylinder 3, and the degree of the transition angle β is 30°-60°.

[0034] Furthermore, the inclination angle ε is 30-60°.

[0035] Furthermore, the diameter of the arc-starting emitter 1 is 8 to 18 mm.

[0036] Furthermore, the intermediate cylinder 2 is made of pure copper or copper-based alloy and has a diameter of 20 to 30 mm.

[0037] In summary, the cathode head for the plasma device, the arc-striking emitter 1 is formed by an arc-striking cylinder and an arc-striking spherical segment, and the arc-striking emitter 1 is made of tungsten or a tungsten alloy. Since the tungsten alloy has an extremely high melting point and excellent high temperature resistance, the outer surface of the arc-striking emitter 1 is not easily burned by the arc flame flow to form a pit during operation, thereby enhancing the service life of the cathode head. At the same time, the design of the threaded hole 5 reduces the use of materials while reducing the accumulation of heat in the cathode head, increasing the heat dissipation area and improving the cooling effect; and the angle γ between the straight line where the hole wall of the threaded hole 5 is located and the vertical direction is matched with the inclination angle ε of the connecting end of the plasma torch water-cooling tube 6, and the inclined surface where the inclination angle ε is located is in contact with the threaded hole 5, so that the cathode head body and the plasma torch water-cooling tube 6 are metal hard sealed, which can meet the sealing requirements under high water pressure environment.

[0038] In addition, the cathode head can be easily disassembled and installed by using a wrench in combination with the external hexagonal structure 7; the intermediate cylinder 2 is made of pure copper or copper-based alloy, which can effectively dissipate the heat accumulated in the cathode head and extend the service life of the cathode head; the transition angle α between the arc-starting cylinder 1 and the intermediate cylinder 2, the transition angle β set on the left end face of the tail cylinder 3, and the transition angle δ between the left end of the external hexagonal structure 7 and the intermediate cylinder 2 are mutually coordinated, which is beneficial to the generation and concentration of the plasma jet on the cathode head.

[0039] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0040] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A cathode head for a plasma device, characterized in that: The invention comprises a cathode head body, wherein the cathode head body comprises an arc-starting emitter (1), an intermediate cylinder (2), a tail cylinder (3) and a connecting portion (4) for contacting with a plasma torch water-cooling pipe (6) which are connected in sequence from left to right; the arc-starting emitter (1) is made of tungsten or a tungsten alloy, and is formed integrally with an arc-starting cylinder and an arc-starting spherical segment; one end of the arc-starting cylinder is fixed to one end of the intermediate cylinder (2); a thread is provided in the intermediate cylinder (2) The threaded hole (5) has an angle γ between the straight line where the hole wall of the threaded hole (5) is located and the vertical direction, and the degree of the angle γ is 90° to 120°; the connection end of the plasma torch water cooling tube (6) is provided with an inclination angle ε, and the inclined surface where the inclination angle ε is located abuts against the threaded hole (5), so as to realize the hard seal between the cathode head body and the plasma torch water cooling tube (6); the outer side of one end where the intermediate cylinder (2) is connected to the tail cylinder (3) is provided with a clamping structure for easy disassembly and assembly; There is a transition angle α between the arc-striking cylinder and the intermediate cylinder (2), and the degree of the transition angle α is 60° to 90°; The clamping structure is an outer hexagonal structure (7); There is a transition angle δ between the left end of the outer hexagonal structure (7) and the middle cylinder (2), and the degree of the transition angle δ is 110° to 150°; The left end surface of the tail cylinder (3) is provided with a transition angle β, and the degree of the transition angle β is 30°-60°.

2. The cathode head for a plasma device according to claim 1, characterized in that: One end of the arc-striking cylinder is fixedly welded to one end of the middle cylinder (2).

3. The cathode head for a plasma device according to claim 1, characterized in that: The inclination angle ε is between 30° and 60°.

4. The cathode head for a plasma device according to claim 1, characterized in that: The diameter of the arc-starting emitter (1) is 8 to 18 mm.

5. The cathode head for a plasma device according to claim 1, characterized in that: The intermediate cylinder (2) is made of pure copper or copper-based alloy and has a diameter of 20 to 30 mm.

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