CN110677974A

CN110677974A - Plasma generator

Info

Publication number: CN110677974A
Application number: CN201911105617.9A
Authority: CN
Inventors: 曹修全; 陈林; 何润东; 陈艳
Original assignee: Sichuan University of Science and Engineering
Current assignee: Sichuan University of Science and Engineering
Priority date: 2019-11-13
Filing date: 2019-11-13
Publication date: 2020-01-10
Anticipated expiration: 2039-11-13
Also published as: CN110677974B

Abstract

The invention provides a plasma generator, and belongs to the field of plasma equipment. The plasma generator mainly comprises a cathode part, an arc striking part and an anode part. The arc striking part is arranged between the cathode part and the anode part and is used for triggering electric arcs between the anode part and the cathode part, the electric arcs ionize working gas to generate plasma, and the plasma is sprayed out through the anode part. The cathode part comprises a cathode seat and a cathode head; the base body of the cathode base comprises a cooling channel; the cathode head is connected with the base body. Cooling water is introduced into the cooling channel through the water inlet, and the cooling water takes away a part of heat when flowing through the cathode head, so that the cathode head can be effectively cooled; thereby prolonging the service life of the cathode head. In addition, the arc striking part is arranged between the cathode head and the anode body, so that the arc voltage stability can be improved while the distance between the cathode and the anode is enlarged.

Description

Plasma generator

Technical Field

The invention relates to the field of plasmas, in particular to a plasma generator.

Background

Compared with high-temperature heat sources such as laser and electron beams, the arc plasma generator has low requirements on the use environment, low operation and maintenance cost and no dependence on the treated object, and the generated thermal plasma jet has high temperature (the highest temperature exceeds 1PA20191101qhg ℃, thereby being a cheap and easily-obtained high-temperature heat source. Based on the excellent characteristics of the arc plasma generator, the generated arc plasma jet is widely applied to the fields of spraying, metallurgy, hazardous waste treatment and the like. Accordingly, various types of arc plasma generator configurations have been developed. However, due to the high current density of the arc root, the generated heat accelerates the ablation speed of the electrode; especially the cathode head, which is more easily ablated. Therefore, it is important to provide a plasma generator capable of effectively cooling the cathode head.

Disclosure of Invention

The invention aims to provide a plasma generator which comprises a cooling channel and can effectively cool a cathode head by injecting cooling water.

The invention is realized by the following steps:

a plasma generator, comprising:

a cathode portion comprising a cathode base and a cathode head; the cathode base comprises a base body, the base body comprises a cooling channel, and the cooling channel comprises a water inlet and a water outlet; the cathode head is connected with one end of the cooling channel.

An arc initiation portion comprising an arc initiation housing and an arc initiation ring; the arc striking ring is arranged in the arc striking shell and comprises a middle through hole, and the middle through hole extends along the axial direction of the arc striking ring; the arc striking ring comprises a first end face and a second end face which are oppositely arranged.

The arc striking shell is connected with the cathode base in an insulating way; the first end surface of the arc striking ring is opposite to the cathode head at intervals; and an anode portion comprising an anode housing and an anode body disposed within the anode housing and connected thereto; the anode body includes an arc channel that extends along a length of the anode body.

The anode shell is connected with the arc striking shell in an insulating way, and an anode head of the anode body is arranged opposite to the second end surface of the arc striking ring at intervals; the arc channel and the middle through hole are coaxially arranged. And a working gas inlet hole is formed in the arc striking shell, is arranged between the arc striking ring and the anode head and is used for introducing working gas.

Further, the arc striking shell is of a cylindrical structure and comprises an inner cylinder, a connecting ring and an outer flange which are coaxially arranged, and the inner cylinder is arranged in the outer flange and is coaxially arranged with the outer flange. The outer wall of inner tube and the inner wall interval setting of outside flange to form annular space. One end of the inner cylinder is connected with one end of the external flange through a connecting ring, so that one end of the annular space is closed, and the other end of the annular space is an annular opening. The inner cylinder, the external flange and the connecting ring are enclosed to form an annular groove. The external flange is connected with the anode shell, an insulating gasket is arranged between the external flange and the anode shell, and the insulating gasket seals an opening of the annular groove. The connecting flange is connected with a working gas inlet pipe, which extends along the radial direction of the connecting flange and extends into the annular groove.

The inner hole of the inner cylinder is a stepped hole, and a positioning boss is arranged in the inner hole and is close to the anode head; the second end surface of the arc striking ring is abutted with the positioning boss. The inner cylinder is provided with a plurality of working gas inlet holes, and the working gas inlet holes extend along the tangential direction of the inner cylinder and extend from the outer surface of the inner cylinder to the inner surface of the positioning boss. The anode head is conical; and a chamfer is arranged at one end of the arc channel close to the anode head.

After entering the annular groove, working gas enters a space between the arc striking ring and the working space of the anode head through a working gas inlet; and because the axis of the air inlet hole of the working gas is vertical to the radius of the inner cylinder, the working gas enters the working space in a rotating direction and forms a vortex. Meanwhile, the anode head is conical, so that the eddy current can rotate around the end part of the anode head and generate plasma under the action of an electric field; the plasma is ejected through the plasma channel along the conical surface of the anode head. The tangential design of the gas inlet and the conical design of the anode head are matched with each other, so that the working gas can stay in a working space for a longer time, and more plasmas are generated through full reaction; and improves the stability of the arc voltage.

Furthermore, an annular water tank is arranged on the arc starting ring and extends along the outer circumferential surface of the arc starting ring; the arc striking shell seals the annular water tank to form a closed cooling space; the arc striking shell is also provided with an arc striking water inlet pipe and an arc striking water outlet pipe, and the arc striking water inlet pipe and the arc striking water outlet pipe are respectively communicated with the cooling space.

After the annular water tank is arranged, the arc striking ring can be effectively cooled by introducing cooling water into the cooling space.

Furthermore, the cathode base further comprises an end cover, an internal water flow pipe, a cathode water inlet pipe and a cathode water outlet pipe, wherein the end cover is connected with one end of the cooling channel in a sealing mode, and the cathode head is connected with the other end of the cooling channel in a sealing mode. The inside water flow pipe is arranged in the cooling channel, the inside water flow pipe and the inner wall of the cooling channel are arranged at intervals to form a water flow channel, one end of the inside water flow pipe is connected with the end cover in a sealing mode, and the other end of the inside water flow pipe extends to the position of the cathode head and is arranged at intervals with the cathode head. The cathode water inlet pipe is communicated with the water flow channel, and the cathode water outlet pipe is communicated with the internal water flow pipe.

Cooling water is introduced into the cathode water inlet pipe, and the cooling water directly cools the cathode after reaching the cathode head along the internal water flow pipe; then the cooling water flows back to the cathode water outlet pipe along the channel between the outside of the internal water flow pipe and the inside of the water flow channel and is discharged through the cathode water outlet pipe. The structure prolongs the detention time of the cooling water in the cathode part, so that the cooling water can be subjected to sufficient heat exchange, and the cooling efficiency is improved.

Further, the method comprises the following steps of; the cathode head comprises a tungsten rod and a mounting seat; the mounting seat is of a cylindrical structure and comprises a mounting cylinder; the mounting cylinder comprises a closed end and an open end, the closed end is conical and extends into the cooling channel, and the outer wall of the mounting cylinder and the inner wall of the cooling channel are arranged at intervals. The tungsten rod is embedded in the mounting cylinder and is arranged opposite to the arc striking ring at intervals.

Because the tungsten rod has good high temperature resistance, the tungsten rod bears the high temperature of the cathode arc root; and the tungsten rod is cooled by the good heat-conducting property of the mounting seat, so that the cathode head is prevented from being quickly ablated due to continuous high temperature, and the service life of the cathode head is prolonged.

The closed end of the mounting cylinder is designed to be conical, namely, one end of the mounting cylinder, which is positioned in the cooling channel, is conical; the design enables the cooling water from the inner water flow pipe to flow to the gap between the mounting cylinder and the cooling channel along the conical surface of the closed end, thereby facilitating the heat dissipation of the wall of the mounting cylinder. If the closed end adopts a plane, the cooling water in the inner water flow pipe naturally diffuses in the radial direction along the end surface after flowing onto the plane of the closed end, and then flows towards the direction of the cathode water outlet pipe. At this time, the cooling water is difficult to effectively cool the region between the mounting cylinder and the inside of the cooling passage.

Further, the mounting seat further comprises a positioning ring, and the positioning ring is fixedly connected with one end of the mounting cylinder. The cathode part also comprises a cathode fixing sleeve; an external thread section is arranged at one end of the seat body close to the cathode head, and the cathode fixing sleeve comprises an end baffle ring; the fixed cover of negative pole cover establish on the external screw thread section and with external screw thread section threaded connection, the tip keep off the ring with the holding ring butt.

The end faces of the mounting seat and the cooling channel of the cathode seat can be tightly matched by screwing the cathode fixing sleeve, so that cooling water is prevented from leaking.

Furthermore, the cathode part also comprises an insulating sleeve, a locking ring and a connecting cylinder, and one end of the connecting cylinder is connected with the arc striking shell; the insulation sleeve is arranged in the connecting cylinder, and the locking ring is sleeved on the connecting cylinder and used for fixing the insulation sleeve. The seat body is partially embedded in the insulating sleeve.

Further, the cathode part further comprises an internal thread ring and a locking nut, wherein the internal thread ring is fixed in the insulating sleeve; the base body is in threaded connection with the internal thread ring. The pedestal including the external screw thread section, lock nut with the external screw thread section is connected, and with the tip butt of insulating cover.

A base body of the rotary cathode part, which can move axially relative to the internal thread ring while rotating; thereby can adjust the relative distance of negative pole head and striking part and positive pole part, and then can adjust the arc and press.

Further, the method comprises the following steps of; the connecting cylinder comprises a cylinder body and a baffle ring, the baffle ring is arranged at one end of the cylinder body, and the outer circumferential surface of the baffle ring is connected with the inner circumferential surface of the cylinder body. The inner end of the insulating sleeve is abutted against the baffle ring; the outer circumferential surface of the seat body is in sealing fit with the inner circumferential surface of the insulating sleeve; a groove is formed in one end, close to the blocking ring, of the outer circumferential surface of the insulating sleeve, and the blocking ring and the cylinder body enclose the groove into a closed annular space. The insulating sleeve is provided with a plurality of shielding gas inlet holes, and the shielding gas inlet holes extend along the tangential direction of the insulating sleeve; and a protective gas inlet pipe is arranged on the connecting cylinder, and gas can enter the annular space through the protective gas inlet pipe and enter between the cathode head and the arc striking ring through the protective gas inlet hole. The first end face of the arc ignition ring is provided with a conical concave part, and the end part of the cathode head is positioned in the conical concave part and is arranged at an interval with the bottom of the conical concave part.

Because the shielding gas inlet hole is vertical to the diameter direction of the insulating sleeve, the shielding gas forms vortex between the cathode head and the arc striking ring; thereby make the protective gas can repeatedly surround the negative pole head to the dwell time of extension protective gas in negative pole head department, and then form effective protection to the negative pole head.

Further, the anode shell comprises an anode outer cylinder and an anode flange; the outer cylinder is connected with the arc striking shell through an anode flange; the anode body is arranged in the anode outer cylinder, the outer end of the anode body is connected with an annular plate, and the annular plate is connected with the end part of the anode outer cylinder in a sealing way. The anode part also comprises a cylindrical water separating sleeve; the water-proof sleeve is arranged in the anode outer cylinder and is arranged at an interval with the inner wall of the anode outer cylinder to form a water flow channel; one end of the water separating sleeve is fixedly connected with the inner edge of the anode flange, and the other end of the water separating sleeve is arranged at an interval with the annular plate. The anode body is embedded in the anode outer cylinder, a spiral groove is formed in the anode body, and the anode part further comprises an anode water inlet pipe and an anode water outlet pipe; the anode water inlet pipe is communicated with the spiral groove, and the anode water outlet pipe is communicated with the water flow channel; the cooling water can enter the spiral groove through the anode water inlet pipe and flow into the anode water outlet pipe through the water flow channel.

After cooling water enters the spiral groove, the anode body can be effectively cooled; and after the water flows out of the spiral groove, the water does not directly flow into the anode water outlet pipe, but flows into the anode water outlet pipe after passing through the water flow channel. Under the condition of constant water flow speed, the design prolongs the detention time of the cooling water in the anode part, thereby carrying out sufficient heat exchange; the cooling efficiency is improved.

Furthermore, a water inlet groove is formed in the circumferential surface of the anode body and close to the anode head, and a water return groove is formed in the circumferential surface of the anode body and close to the annular plate; the anode body is provided with a plurality of spiral grooves, one end of each spiral groove is communicated with the water inlet groove, and the other end of each spiral groove is communicated with the water return groove; the water return groove is communicated with the water flow channel.

The anode body is provided with a plurality of spiral grooves, and the water inlet groove and the water return groove can be communicated through the spiral grooves to form a plurality of water flow channels; thereby enabling further improvement in cooling efficiency.

The technical scheme provided by the invention has the beneficial effects that:

when the plasma generator is used, the cathode base is connected with the negative electrode of the power supply, and the anode body is connected with the negative electrode of the power supply; and working gas (nitrogen, argon, air or the mixture of any two of the nitrogen, the argon and the air) is introduced into the gap between the arc striking ring and the anode head through a working gas inlet hole. At the moment, under the action of an electric field between the anode body and the cathode head, working gas discharges to generate plasma; and is ejected through the arc channel by the gas flow. Meanwhile, cooling water is introduced into the cooling channel through the water inlet, and the cooling water takes away a part of heat when flowing through the cathode head, so that the cathode head can be effectively cooled; thereby prolonging the service life of the cathode head. In addition, the arc striking part is arranged between the cathode head and the anode body, so that the arc voltage stability can be improved while the distance between the cathode and the anode is enlarged.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a perspective view of a plasma generator provided by an embodiment of the present invention from a first perspective;

FIG. 2 is a perspective view of a plasma generator provided by an embodiment of the present invention from a second perspective;

FIG. 3 is a cross-sectional view of a plasma generator along the axis of the cathode inlet and cathode sections provided by an embodiment of the present invention;

FIG. 4 is a cross-sectional view of the cathode portion of FIG. 3 provided in accordance with an embodiment of the present invention;

FIG. 5 is a cross-sectional view of the arc initiation portion of FIG. 3 provided in accordance with an embodiment of the present invention;

FIG. 6 is a partial cross-sectional view of the anode of FIG. 3 according to an embodiment of the present invention;

FIG. 7 is a cross-sectional view of a plasma generator along the axis of the shield gas inlet and cathode portions in accordance with an embodiment of the present invention;

FIG. 8 is a sectional view of the plasma generator along the axis of the arc ignition water inlet pipe and the cathode part according to the embodiment of the invention;

FIG. 9 is a sectional view of a plasma generator along the axis of the working gas inlet and cathode portions according to an embodiment of the present invention;

FIG. 10 is a sectional view of a plasma generator along the axis of the anode outlet tube and the cathode portion according to an embodiment of the present invention;

FIG. 11 is a sectional view of a plasma generator along the axis of the anode inlet and cathode portions according to an embodiment of the present invention;

icon: 010-a plasma generator; 100-a cathode portion; 110-cathode base; 111-end cap; 112-a seat body; 113-internal water flow tube; 114-cathode inlet pipe; 115-cathode water outlet pipe; 120-cathode head; 121-tungsten rod; 122-a mount; 123-mounting the barrel; 124-a positioning ring; 130-cathode fixation sleeves; 140-an insulating sleeve; 141-shielding gas inlet hole; 142-a shielding gas inlet pipe; 150-locking ring; 160-a connector barrel; 161-cylinder; 162-a connecting flange; 163-baffle ring; 170-internal threaded ring; 180-locking the nut; 200-an arc initiation portion; 210-arc striking housing; 211-inner cylinder; 2111 — working gas intake; 212-a connecting ring; 213-an outer flange; 214-an annular groove; 220-arc striking ring; 221-an annular water tank; 230-arc starting water inlet pipe; 240-arc striking water outlet pipe; 250-an insulating pad; 260-working gas inlet pipe; 300-an anode portion; 310-an anode casing; 311-anode outer cylinder; 312-anode flange; 313-water separating sleeve; 320-an anode body; 321-a spiral groove; 322-water inlet tank; 323-water return tank; 324-anode head; 325-annular plate; 326-arc path; 330-anode water inlet pipe; 340-anode water outlet pipe.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

In the description of the present invention, it is to be understood that the terms indicating an orientation or positional relationship are based on the orientation or positional relationship shown in the drawings only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the present invention, unless otherwise expressly stated or limited, the first feature may be present on or under the second feature in direct contact with the first and second feature, or may be present in the first and second feature not in direct contact but in contact with another feature between them. Also, the first feature being above, on or above the second feature includes the first feature being directly above and obliquely above the second feature, or merely means that the first feature is at a higher level than the second feature. A first feature that underlies, and underlies a second feature includes a first feature that is directly under and obliquely under a second feature, or simply means that the first feature is at a lesser level than the second feature.

Example (b):

referring to fig. 1, 2 and 3, the present embodiment provides a plasma generator 010, which has a substantially cylindrical revolving structure as a whole, and mainly includes a cathode portion 100, an arc striking portion 200 and an anode portion 300. Wherein the arc striking part 200 is disposed between the cathode part 100 and the anode part 300, for striking an arc between the anode part 300 and the cathode part 100, the arc ionizes the working gas to generate plasma, and the plasma is ejected through the anode part 300.

Referring to fig. 3 and 4, the cathode portion 100 includes a cathode base 110 and a cathode head 120, the cathode base 110 includes a base body 112 and an insulating sleeve 140, the base body 112 is a stepped cylindrical structure, and is fixedly connected in the insulating sleeve 140 and connected to the arc striking portion 200 through the insulating sleeve 140. A cooling channel is arranged in the base body 112, a cathode water inlet pipe 114 is arranged at a water inlet of the cooling channel, and a cathode water outlet pipe 115 is arranged at a water outlet of the cooling channel. The cathode head 120 is connected to one end of the base body 112 near the arc striking portion 200 and is embedded in one end of the cooling channel.

Referring to fig. 3 and 5, the arc striking part 200 includes an arc striking housing 210 and an arc striking ring 220, wherein the arc striking housing 210 has a circular flange structure, the arc striking ring 220 is embedded in the arc striking housing 210, a middle through hole is disposed in the middle of the arc striking ring 220, one end of the middle through hole is disposed opposite to the cathode head 120 of the cathode part 100 at an interval, and the other end is disposed opposite to the anode part 300 at an interval.

Referring to fig. 3 and 6, the anode part 300 includes an anode housing 310 and an anode body 320, wherein the anode housing 310 includes a cylindrical anode outer cylinder 311 and an anode flange 312, and the anode flange 312 is fixedly connected to the anode outer cylinder 311 and is connected to the arc striking housing 210 by bolts. An insulating pad 250 is also provided between the arc ignition housing 210 and the anode flange 312. The anode body 320 is a circular rod-shaped structure, and the anode body 320 is embedded in the anode casing 310 and is coaxially arranged with the anode casing 310. The middle of the anode casing 310 is provided with an arc channel 326 that extends through the entire anode body 320 along the axis of the anode body 320. The end of the anode body 320 near the arc ignition portion 200 is provided with a tapered anode head 324, and the anode head 324 is spaced opposite to the arc ignition ring 220.

When the cathode part 100 is connected to the negative electrode of the power source and the anode part 300 is connected to the anode of the power source, an electric field is generated between the cathode tabs 120 and the anode tabs 324; when the working gas enters between the arc ignition ring 220 and the anode head 324 from the working gas inlet hole 2111 of the arc ignition shell 210, the working gas is ionized under the action of the electric field to generate plasma; the plasma is ejected through the arc channel.

Further, with continued reference to fig. 4, the cathode base 110 further includes an end cap 111, an insulating sleeve 140, a locking ring 150, a connecting cylinder 160 and an internal water flow pipe 113, the end cap 111 is connected to one end of the base body 112, and the cathode head 120 is connected to the other end of the base body 112, so that both ends of the cooling channel are sealed. The insulating sleeve 140 is cylindrical, and a part of the base 112 is embedded in the insulating sleeve 140. The locking ring 150 is sleeved on the base 112 for locking the base 112 and the insulating sleeve 140. The end cap 111 is provided with a cathode connector for connecting with a cathode of a power supply.

Specifically, in order to fix the seat body 112 in the insulating sleeve 140, an internal thread ring 170 is arranged in the insulating sleeve 140, and the internal thread ring 170 abuts against a boss in an inner hole of the insulating sleeve 140; the boss limits axial movement of the internally threaded ring 170. The seat body 112 is in threaded connection with the internal thread ring 170, and the part of the seat body 112 located outside the insulating sleeve 140 is provided with an external thread section; the external thread section is provided with a locking nut 180, and the locking nut 180 abuts against the end of the insulating sleeve 140, thereby preventing the seat body 112 from loosening from the internal thread ring 170.

When the distance between the cathode head 120 and the arc striking ring 220 needs to be adjusted, the locking bolt is loosened, and then the base body 112 is rotated to rotate and axially move in the internal thread ring 170; when the locking nut 180 is moved to a preset position, the locking nut is tightened.

The connecting cylinder 160 includes a cylinder body 161 and a cathode flange fixedly coupled to one end of the cylinder body 161 and coupled to the arc striking part 200 by bolts. The insulating sleeve 140 is embedded in the cylinder 161; thereby making the holder body 112 insulated from the arc striking part 200.

An inner water flow tube 113 is disposed in the cooling passage with one end connected to the inner surface of the end cap 111 and the other end disposed adjacent to and spaced from the cathode head 120. The outer diameter of the inner water flow tube 113 is smaller than the inner diameter of the cooling channel so that a water flow channel is formed between the inner water flow tube 113 and the inside of the cooling channel. The cathode inlet pipe 114 is disposed near the end cap 111, and passes through the outer wall of the base 112 and the inner water flow pipe 113 to communicate with the inner water flow pipe 113. The cathode outlet pipe 115 passes through the outer wall of the seat body 112 and is communicated with the water flow channel. The cooling water flows in the direction close to the cathode tabs 120 after entering the inner water flow tube 113, and flows back in the opposite direction along the water flow channel after passing through the cathode tabs 120, so that the cooling water forms a complete flow channel.

Due to the structural limitation, the cathode inlet pipe 114 and the cathode outlet pipe 115 are difficult to be arranged at one end of the base body 112 close to the cathode head 120; and the most easily ablated portion of the entire cathode portion 100 is the cathode tab 120. The design not only enables the cooling water to form a complete flow channel; in addition, it is also possible to make the cooling water first reach the cathode tabs 120 to cool the cathode tabs 120 first, and then, to cool the holder body 112 itself by means of backflow.

The cathode head 120 includes a mounting seat 122 and a cylindrical tungsten rod 121, the mounting seat 122 is connected with the seat body 112 and extends into the water flow channel, and the tungsten rod 121 is installed in the mounting seat 122. Specifically, the mounting seat 122 includes a mounting cylinder 123 and a positioning ring 124, and the positioning ring 124 is fixedly connected to an outer wall of the mounting cylinder 123. In order to fix the mounting seat 122 and the seat body 112, a thread is disposed at one end of the seat body 112 close to the cathode head 120, and a cathode fixing sleeve 130 is sleeved on the external thread section. When the cathode pouch 130 is tightened against the seat 112, the end stop ring 163 at the end of the cathode pouch 130 abuts the retaining ring 124 of the mounting block 122, thereby securing the mounting block 122 in the cooling passage. Moreover, chamfers are arranged at the end parts of the cooling channels of the positioning ring 124 and the seat body 112, so that the matching surfaces of the positioning ring 124 and the seat body 112 can be tightly matched, and the leakage of cooling water is prevented.

The mounting cylinder 123 comprises a closed end and an open end, the closed end is located in the cooling channel, and the open end is arranged opposite to the arc striking ring 220 at an interval; the tungsten rod 121 is embedded in the mounting cylinder 123 through the open end. Also, the outer diameter of the mounting cylinder 123 is smaller than the inner diameter of the cooling passage, and the closed end of the mounting cylinder 123 is conical. The contact area of the mounting cylinder 123 and the cooling water is larger, and after the closed end of the mounting cylinder 123 is designed to be conical, the cooling water coming out of the inner water flow pipe 113 can flow into the annular gap between the mounting cylinder 123 and the inner wall of the cooling channel along the conical surface of the closed end; so that the existing higher temperature in the annular gap is forced out, thereby facilitating the heat dissipation of the wall of the mounting cylinder 123.

Further, with continuing reference to fig. 4 and with reference to fig. 7, the connecting cylinder 160 further includes a stop ring 163, the stop ring 163 is disposed coaxially with the cylinder 161, and an outer circumferential surface of the stop ring 163 is connected with an inner circumferential surface of the cylinder 161. One end of the insulating sleeve 140 located in the connecting cylinder 160 abuts against the stop ring 163, and the outer circumferential surface of the seat body 112 is in sealing fit with the inner circumferential surface of the insulating sleeve 140. A groove is formed at one end of the outer circumferential surface of the insulating sleeve 140 close to the baffle ring 163, and the baffle ring 163 and the cylinder 161 enclose the groove into a closed annular space. A plurality of shielding gas inlet holes 141 are formed in the insulating sleeve 140, and the shielding gas inlet holes 141 extend along the tangential direction of the insulating sleeve 140; the connecting cylinder 160 is provided with a shielding gas inlet pipe, and gas can enter the annular space through the shielding gas inlet pipe. The outer wall of the cathode fixing sleeve 130 is arranged in a gap with the inner wall of the insulating sleeve 140; the shielding gas can enter the gap through the shielding gas inlet hole 141, and then enter between the cathode head 120 and the arc striking ring 220. The end surface of the arc ignition ring 220 close to the cathode head 120 is provided with a conical concave part, and the end part of the cathode head 120 is positioned in the conical concave part and is arranged at a distance from the bottom of the conical concave part.

The above structure allows the insulating sleeve 140 to function not only as an insulator, but also to form an annular space for receiving shielding gas in cooperation with the connector cylinder 160. After entering the annular space through the shielding gas inlet pipe, the shielding gas (inert gas) enters between the cathode head 120 and the arc striking ring 220 through the shielding gas inlet holes 141 uniformly distributed on the insulating sleeve 140. Since the shielding gas inlet hole 141 is perpendicular to the diameter direction of the insulating sleeve 140, it makes the shielding gas form a vortex between the cathode head 120 and the arc striking ring 220; thereby enabling the shielding gas to repeatedly surround the cathode taps 120 and extending the residence time of the shielding gas at the cathode taps 120, thereby effectively protecting the cathode taps 120.

With continuing reference to fig. 5 and with reference to fig. 8 and 9, the arc striking housing 210 is a cylindrical structure and includes an inner cylinder 211, a connecting ring 212 and an outer flange 213 coaxially disposed, the inner cylinder 211 is disposed in the outer flange 213, and one end of the inner cylinder 211 is connected to one end of the outer flange 213 through the connecting ring 212, such that the inner cylinder 211, the outer flange 213 and the connecting ring 212 enclose an annular groove 214. The arc striking housing 210 may be formed by forming an annular groove on an end surface of a circular flange, and the inner cylinder 211 is an inner groove wall of the annular groove, the connection ring 212 is a groove bottom of the annular groove 214, the outer flange 213 and an outer groove wall of the annular groove. The external flange 213 is connected with the anode casing 310, an insulating gasket 250 is arranged between the external flange 213 and the anode casing 310, and the annular groove is sealed by the insulating gasket 250; and the external flange 213 is connected with a working gas inlet pipe 260, and the working gas inlet pipe 260 is communicated with the annular groove. That is, the working gas can enter into the annular groove through the working gas inlet pipe 260.

A positioning boss is arranged in the inner hole of the inner cylinder 211, so that the inner hole becomes a stepped hole; the positioning boss is disposed proximate the anode head 324; the second end face of the arc striking ring 220 is abutted with the positioning boss. The inner cylinder 211 is provided with a plurality of working gas inlet holes 2111, and the working gas inlet holes 2111 extend along the tangential direction of the inner cylinder 211 and extend from the outer surface of the inner cylinder 211 to the inner surface of the positioning boss. The design enables the working gas in the sealing groove to directly enter between the arc ignition ring 220 and the anode head 324 along other working gas inlet holes. Also, the anode head 324 is conical; a chamfer is provided at the end of the arc channel near the anode head 324; the end of the arc runner 220 adjacent the anode head 324 is conical.

Working gas is stored in the annular groove, and then enters between the arc striking ring 220 and the anode head 324 through working gas inlet holes 2111 which are all arranged on the inner cylinder 211; the flow rate of the gas of each air inlet hole is equal, and the direction of the gas is vertical to the diameter direction of the inner cylinder 211; thereby causing the working gas to form a stable and uniform vortex between the arc runner 220 and the anode head 324. Also, since the anode head 324 and the arc ignition ring 220 are both conical, they cause the eddy current to cause the working gas to gradually approach from the outermost layer to the center, and when moving to the vicinity of the center, they are ionized to form a plasma.

Further, an annular water channel 221 is arranged on the arc ignition ring 220, and the annular water channel 221 extends along the outer circumferential surface of the arc ignition ring 220; the arc striking housing 210 encloses the annular water tank 221 to form a closed cooling space. The arc striking shell 210 is further provided with an arc striking water inlet pipe 230 and an arc striking water outlet pipe 240, and the arc striking water inlet pipe 230 and the arc striking water outlet pipe 240 are respectively communicated with the cooling space.

With continuing reference to fig. 6 and with further reference to fig. 10 and 11, the anode casing 310 includes an anode outer cylinder 311 and an anode flange 312; the outer barrel is connected to the arc ignition housing 210 by an anode flange 312. The anode body 320 is arranged in the anode outer cylinder 311, the outer end of the anode body 320 is connected with an annular plate 325, and the annular plate 325 is hermetically connected with the end of the anode outer cylinder 311 through a screw. The anode flange 312 is provided with an anode connector for connection with the anode of the power supply.

Anode portion 300 further includes a cylindrical water-stop jacket 313; the water blocking sleeve 313 is arranged in the anode outer cylinder 311, the outer circumferential surface of the water blocking sleeve 313 and the inner wall of the anode outer cylinder 311 are arranged at intervals to form a water flow channel, and the inner circumferential surface of the water blocking sleeve 313 is attached to the outer circumferential surface of the anode body 320. One end of the water-blocking sleeve 313 is fixedly connected with the inner edge of the anode flange 312, and the other end is arranged at a distance from the annular plate 325. The anode body 320 is provided with a spiral groove 321, and the anode part 300 further includes an anode inlet pipe 330 and an anode outlet pipe 340. The anode water inlet pipe 330 is communicated with the spiral groove 321, and the anode water outlet pipe 340 is communicated with the water flow channel. The cooling water can enter the spiral groove 321 through the anode inlet pipe 330 and flow to the anode outlet pipe 340 through the water flow passage.

After the cooling water enters the spiral groove 321, it can effectively cool the anode body 320; and, after exiting from the spiral groove 321, it does not directly flow into the anode outlet pipe 340, but passes through the water flow channel and then enters the anode outlet pipe 340. The above design extends the residence time of the cooling water in the anode part 300 under a constant water flow rate, thereby enabling sufficient heat exchange; the cooling efficiency is improved.

Further, a water inlet groove 322 extending along the circumference is arranged on the circumferential surface of the anode body 320 near the anode head 324; a water return groove extending along the circumference is provided on the circumferential surface of the anode body 320 near the annular plate 325. A plurality of spiral grooves 321 are uniformly arranged on the anode body 320, one end of each spiral groove 321 is communicated with the water inlet groove 322, and the other end of each spiral groove 321 is communicated with the water return groove; the water return groove is communicated with the water flow channel.

A plurality of spiral grooves 321 are formed in the anode body 320, and the water inlet groove 322 and the water return groove 323 can be communicated through the plurality of spiral grooves 321 to form a plurality of water flow channels; thereby enabling further improvement in cooling efficiency. And, the above design makes the cooling water buffered in the water inlet tank 322 first, and when the plurality of spiral grooves 321 extend into the water inlet tank 322 and the water return tank 323, they form a plurality of uniform water inlets on the wall of the water inlet tank 322 and a plurality of uniform water outlets on the wall of the water return tank 323, so that the whole anode body 320 is cooled uniformly.

The arc plasma generator 010 has a simple and compact structure, and metal sealing is adopted to replace an O-shaped sealing ring at an important core position, so that the bearing capacity of the arc plasma generator 010 on high temperature is improved, the service life of the arc plasma generator 010 is prolonged, and the working thermal efficiency of the arc plasma generator 010 is improved.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A plasma generator, comprising:

a cathode portion (100), the cathode portion (100) comprising a cathode holder (110) and a cathode head (120); the cathode base (110) comprises a base body (112), the base body (112) comprises a cooling channel, and the cooling channel comprises a water inlet and a water outlet; the cathode head (120) is connected with the base body (112) and is positioned at one end of the cooling channel;

an arc initiation portion (200), the arc initiation portion (200) comprising an arc initiation housing (210) and an arc initiation ring (220); the arc striking ring (220) is arranged in the arc striking shell (210), the arc striking ring (220) comprises a middle through hole, and the middle through hole extends along the axial direction of the arc striking ring (220); the arc ignition ring (220) comprises a first end surface and a second end surface which are oppositely arranged;

the arc striking shell (210) is connected with the cathode base (110) in an insulating way; the first end surface of the arc ignition ring (220) is opposite to the cathode head (120) at an interval; and

an anode portion (300), the anode portion (300) comprising an anode casing (310) and an anode body (320), the anode body (320) being disposed within the anode casing (310) and connected to the anode casing (310); the anode body (320) comprising an arc channel (326) extending along a length direction of the anode body (320);

the anode shell (310) is connected with the arc striking shell (210) in an insulating mode, and an anode head (324) of the anode body (320) is arranged opposite to the second end face of the arc striking ring (220) at an interval; the arc channel and the middle through hole are coaxially arranged;

the arc striking shell (210) is provided with a working gas inlet hole (2111), and the working gas inlet hole (2111) is arranged between the arc striking ring (220) and the anode head (324) and used for leading in working gas.

2. The plasma generator of claim 1, wherein:

the arc striking shell (210) is of a cylindrical structure and comprises an inner cylinder (211), a connecting ring (212) and an outer flange (213) which are coaxially arranged, the inner cylinder (211) is arranged in the outer flange (213), and one end of the inner cylinder (211) is connected with one end of the outer flange (213) through the connecting ring (212), so that the inner cylinder (211), the outer flange (213) and the connecting ring (212) are encircled to form an annular groove;

the external flange (213) is connected with the anode shell (310), an insulating gasket (250) is arranged between the external flange (213) and the anode shell (310), and the annular groove is sealed by the insulating gasket (250); the external flange (213) is connected with a working gas inlet pipe (260), and the working gas inlet pipe (260) is communicated with the annular groove;

an inner hole of the inner cylinder (211) is a stepped hole, a positioning boss is arranged in the inner hole, and the positioning boss is arranged close to the anode head (324); the second end face of the arc striking ring (220) is abutted with the positioning boss;

the inner cylinder (211) is provided with a plurality of working gas inlet holes (2111), and the working gas inlet holes (2111) extend along the tangential direction of the inner cylinder (211) and extend from the outer surface of the inner cylinder (211) to the inner surface of the positioning boss;

the anode head (324) is conical; one end of the arc channel close to the anode head (324) is provided with a chamfer.

3. The plasma generator according to claim 1 or 2, wherein:

an annular water tank (221) is arranged on the arc ignition ring (220), and the annular water tank (221) extends along the outer circumferential surface of the arc ignition ring (220); the arc striking shell (210) seals the annular water tank (221) to form a closed cooling space;

the arc striking shell (210) is further provided with an arc striking water inlet pipe (230) and an arc striking water outlet pipe (240), and the arc striking water inlet pipe (230) and the arc striking water outlet pipe (240) are respectively communicated with the cooling space.

4. The plasma generator of claim 1, wherein:

the cathode base (110) further comprises an end cover (111), an internal water flow pipe (113), a cathode water inlet pipe (114) and a cathode water outlet pipe (115), the end cover (111) is connected with one end of the cooling channel in a sealing mode, and the cathode head (120) is connected with the other end of the cooling channel in a sealing mode;

the inner water flow pipe (113) is arranged in the cooling channel, the inner water flow pipe (113) and the inner wall of the cooling channel are arranged at intervals to form a water flow channel, one end of the inner water flow pipe (113) is hermetically connected with the end cover (111), and the other end of the inner water flow pipe extends to the cathode head (120) and is arranged at an interval with the cathode head (120);

the cathode water outlet pipe (115) is communicated with the water flow channel, and the cathode water inlet pipe (114) is communicated with the inner water flow pipe (113).

5. The plasma generator of claim 3, wherein:

the cathode head (120) comprises a tungsten rod (121) and a mounting seat (122);

the mounting seat (122) is of a cylindrical structure and comprises a mounting cylinder (123); the mounting cylinder (123) comprises a closed end and an open end, the closed end is conical and extends into the cooling channel, and the outer wall of the mounting cylinder (123) and the inner wall of the cooling channel are arranged at intervals;

the tungsten rod (121) is embedded in the mounting cylinder (123) and is arranged opposite to the arc striking ring (220) at an interval.

6. The plasma generator of claim 5, wherein:

the mounting seat (122) further comprises a positioning ring (124), and the positioning ring (124) is fixedly connected with one end of the mounting cylinder (123);

the cathode portion (100) further comprises a cathode fixture sleeve (130); an external thread section is arranged at one end of the base body (112) close to the cathode head (120), and the cathode fixing sleeve (130) comprises an end baffle ring (163); the cathode fixing sleeve (130) is sleeved on the external thread section and is in threaded connection with the external thread section, and the end part blocking ring (163) is abutted to the positioning ring (124).

7. The plasma generator of claim 2, wherein:

the cathode part (100) further comprises an insulating sleeve (140), a locking ring (150) and a connecting cylinder (160), and one end of the connecting cylinder (160) is connected with the arc striking shell (210); the insulating sleeve (140) is arranged in the connecting cylinder (160), and the locking ring (150) is sleeved on the connecting cylinder (160) and used for fixing the insulating sleeve (140);

the base body (112) is partially embedded in the insulating sleeve (140).

8. The plasma generator of claim 7, wherein:

the cathode portion (100) further comprising an internally threaded ring (170) and a retaining nut (180), the internally threaded ring (170) being secured within the insulating sleeve (140); the seat body (112) is in threaded connection with the internal thread ring (170);

the seat body (112) comprises an external thread section, and the locking nut (180) is connected with the external thread section and is abutted against the end part of the insulating sleeve (140).

9. The plasma generator of claim 7, wherein:

the connecting cylinder (160) comprises a cylinder body (161) and a baffle ring (163), wherein the baffle ring (163) is arranged at one end of the cylinder body (161), and the outer circumferential surface of the baffle ring (163) is connected with the inner circumferential surface of the cylinder body (161);

the inner end of the insulating sleeve (140) is abutted against the baffle ring (163); the outer circumferential surface of the base body (112) is in sealing fit with the inner circumferential surface of the insulating sleeve (140); a groove is formed in one end, close to the baffle ring (163), of the outer circumferential surface of the insulating sleeve (140), and the baffle ring (163) and the cylinder body (161) enclose the groove into a closed annular space;

the insulating sleeve (140) is provided with a plurality of shielding gas inlet holes (141), and the shielding gas inlet holes (141) extend along the tangential direction of the insulating sleeve (140); a protective gas inlet pipe is arranged on the connecting cylinder (160), and gas can enter the annular space through the protective gas inlet pipe and enter between the cathode head (120) and the arc ignition ring (220) through the protective gas inlet hole (141);

the first end face of the arc ignition ring (220) is provided with a conical concave part, and the end part of the cathode head (120) is positioned in the conical concave part and is arranged at a distance from the bottom of the conical concave part.

10. The plasma generator of claim 1, wherein:

the anode shell (310) comprises an anode outer cylinder (311) and an anode flange (312); the outer cylinder is connected with the arc striking shell (210) through the anode flange (312); the anode body (320) is arranged in the anode outer cylinder (311), the outer end of the anode body (320) is connected with an annular plate (325), and the annular plate (325) is hermetically connected with the end part of the anode outer cylinder (311);

the anode portion (300) further comprises a cylindrical water-blocking jacket (313); the water separation sleeve (313) is arranged in the anode outer cylinder (311) and is arranged at an interval with the inner wall of the anode outer cylinder (311) to form a water flow channel; one end of the water separating sleeve (313) is fixedly connected with the inner edge of the anode flange (312), and the other end of the water separating sleeve is arranged at an interval with the annular plate (325);

the anode body (320) is embedded in the water separating sleeve (313), a spiral groove (321) is formed in the anode body (320), and the anode part (300) further comprises an anode water inlet pipe (330) and an anode water outlet pipe (340); the anode water inlet pipe (330) is communicated with the spiral groove (321), and the anode water outlet pipe (340) is communicated with the water flow channel; cooling water can enter the spiral groove (321) through an anode water inlet pipe (330) and flow into the anode water outlet pipe (340) through the water flow channel;

a water inlet groove (322) is formed in the circumferential surface of the anode body (320) and close to the anode head (324), and a water return groove (323) is formed in the circumferential surface of the anode body (320) and close to the annular plate (325); the anode body (320) is provided with a plurality of spiral grooves (321), one end of each spiral groove (321) is communicated with the water inlet groove (322), and the other end of each spiral groove (321) is communicated with the water return groove; the water return groove is communicated with the water flow channel.