Disclosure of Invention
The invention aims to provide a cascading plasma generator which solves the problems that a large amount of impurities can be accumulated on the needle tip of an existing arc striking needle and the needle tip is easy to melt.
In order to achieve the above object, the present invention provides a cascade type plasma generator including a cathode assembly, a cathode holder, a cascade assembly, and an anode;
the cascade assembly is arranged between the cathode seat and the anode and is connected with the anode and the cathode seat;
The cathode seat is internally provided with a connecting channel which extends along the axial direction of the cathode seat and penetrates through the upper surface and the lower surface of the cathode seat; the anode is provided with a transmitting channel which extends along the axial direction of the anode and penetrates through the upper surface and the lower surface of the anode, and the cascade assembly is provided with a cascade channel penetrating through the upper surface and the lower surface of the cascade assembly;
the cathode seat is also provided with a gas channel, one end of the gas channel is arranged on the outer peripheral surface of the cathode seat, and the other end of the gas channel is communicated with the connecting channel;
the cathode assembly comprises an arc striking needle, an electron emission needle and an elastic connecting piece, wherein the electron emission needle is inserted into the connecting channel, the bottom end of the electron emission needle is positioned in the connecting channel, and the periphery of the electron emission needle is connected with the cathode seat in a sealing and insulating way;
The electron emission needle is provided with a sliding channel which extends along the axial direction of the electron emission needle and penetrates through the upper surface and the lower surface of the electron emission needle;
The arc striking needle slides and wears to locate in the sliding channel, just the arc striking needle with electron emission needle sealing connection, the top of arc striking needle passes through elastic connection spare elastic connection in electron emission needle, when elastic connection spare is compressed, the bottom of arc striking needle protrusion in electron emission needle's bottom, when elastic connection spare resets, the bottom of electron emission needle protrusion in the bottom of arc striking needle.
Further, the bottom end surface area of the striking pin is smaller than the bottom end surface area of the electron emission pin.
Further, the diameter of the bottom of the electron emission needle gradually decreases from top to bottom, the bottom end surface of the electron emission needle is a plane, and the plane is perpendicular to the axis of the electron emission needle.
Further, a first cooling channel is formed in the electron emission needle, and the first cooling channel is arranged on the periphery of the sliding channel in a surrounding manner and extends along the axial direction of the electron emission needle;
And the two sides of the outer peripheral surface of the electron emission needle are respectively provided with a cooling inlet and a cooling outlet, and the cooling inlet and the cooling outlet are respectively communicated with the first cooling channel.
Further, the cathode assembly further comprises an insulating tube;
The insulation pipe is sleeved on the periphery of the electron emission needle, and the insulation pipe is partially inserted in the connection channel, so that the electron emission needle is insulated from the cathode base.
Further, the locking assembly further comprises an insulating pad;
The insulation pad comprises a sleeving part and a pressing part, the sleeving part is sleeved on the periphery of the electron emission needle, and the pressing part is annularly arranged on the periphery of the sleeving part and extends outwards along the radial direction;
the outer peripheral surface of the sleeving part is tightly attached to the inner wall of the opening, the diameter of the pressing part is larger than that of the opening, and the bottom surface of the pressing part is tightly attached to the top surface of the sealing ring.
Further, the top opening of the sealing stud is provided with a conical surface with gradually reduced outer diameter from top to bottom;
the outer periphery of the sealing ring is a conical surface which is matched and connected with the top opening of the sealing stud.
Further, the sealing stud and the sealing nut are respectively made of different materials.
Further, the elastic connecting piece comprises a corrugated pipe and a corrugated pipe flange fixedly arranged at the top of the corrugated pipe;
the corrugated pipe flange is fixedly connected with the top of the arc striking needle, and the arc striking needle penetrates through the corrugated pipe;
The bellows is hermetically connected to the top of the electron emission needle.
Compared with the prior art, the cascade plasma generator provided by the invention has the beneficial effects that:
The invention provides a cascade plasma generator which comprises a cathode assembly, a cathode seat, a cascade assembly and an anode, wherein high voltage is applied between the cathode assembly and the anode through the cascade assembly and the anode to realize tip discharge through sliding an arc striking needle penetrating through an electron emission needle, so that working gas introduced from a gas channel is punctured to generate an arc, the working gas is ionized to generate plasma, the plasma starts from a connecting channel and is emitted to the outside of the cascade plasma generator through the cascade channel and an emission channel, so that the purpose of providing plasma is achieved, as an elastic connecting piece is compressed, the bottom end of the arc striking needle protrudes out of the bottom end of the electron emission needle, when the elastic connecting piece resets, the bottom end of the arc striking needle is positioned in a sliding channel, therefore, when the cascade plasma generator is started, the elastic connecting piece is compressed, the bottom end of the arc striking needle protrudes out of the connecting channel to generate plasma, the plasma is emitted to the outside of the cascade plasma generator through the connecting channel, the arc striking needle is prevented from being replaced by the arc striking needle, the bottom end of the arc striking needle is prevented from being replaced by the elastic connecting piece, the arc striking needle is prevented from being replaced, and the arc striking needle is prevented from being replaced by the sliding the bottom end of the arc striking needle, and the arc striking needle is prevented from being replaced, the maintenance cost of the device is reduced, and the normal operation of the experiment is ensured.
Detailed Description
The following describes in further detail the embodiments of the present invention with reference to the drawings and examples. The following examples are illustrative of the invention and are not intended to limit the scope of the invention.
As shown in fig. 1-4, a cascade plasma generator 100 according to an embodiment of the present invention includes a cathode assembly 1, a cathode holder 2, a cascade assembly 3 and an anode 4, wherein the anode 4 is disposed below the cathode holder 2 at intervals, the cascade assembly 3 is disposed between the cathode holder 2 and the anode 4 and connects the anode 4 and the cathode holder 2, a connection channel 20 is disposed in the cathode holder 2, the connection channel 20 extends along the axial direction of the cathode holder 2 and penetrates through the upper and lower surfaces of the cathode holder 2, the anode 4 is disposed with a transmission channel 40, the transmission channel 40 extends along the axial direction of the anode 4 and penetrates through the upper and lower surfaces of the anode 4, the cascade assembly 3 is disposed with a cascade channel 30 penetrating through the upper and lower surfaces thereof, the connection channel 20, the cascade channel 30 and the transmission channel 40 are sequentially communicated, the cathode holder 2 is further disposed with a gas channel 21, one end of the gas channel 21 is disposed on the outer circumferential surface of the cathode holder 2, the other end of the gas channel 20 is disposed in communication with the connection channel 20 along the axial direction of the cathode holder 2 and penetrates through the upper and lower surface of the cathode holder 2, the anode 4 is disposed with an electron injection needle 12, the electron injection needle 12 is disposed in the connection channel 12 and the electron injection needle 12 is disposed in the sealing contact needle 12 and extends through the needle 12 and the electron injection needle 12 and the needle 12 is disposed in the sealing contact needle 12 and extends through the needle 12 and the needle 120, the top of the arc striking needle 11 is elastically connected to the electron emission needle 12 through the elastic connection piece 13, when the elastic connection piece 13 is compressed, the bottom end of the arc striking needle 11 protrudes from the bottom end of the electron emission needle 12, and when the elastic connection piece 13 is reset, the bottom end of the electron emission needle 12 protrudes from the bottom end of the arc striking needle 11.
Based on the technical scheme, the cathode assembly 1 is installed through the cathode seat 2, the cathode assembly 1, the cascade assembly 3 and the anode 4 form the cascade plasma generator 100, high voltage is applied between the cathode assembly 1 and the anode 4, tip discharge is realized through sliding the striking needle 11 penetrating through the electron striking needle 12, thereby working gas introduced from the gas channel 21 is punctured to generate an arc, the working gas is ionized to generate plasma, the plasma starts from the connecting channel 20 and is emitted to the outside of the cascade plasma generator 100 through the cascade channel 30 and the emission channel 40, the purpose of providing plasma is achieved, as the elastic connecting piece 13 is compressed, the bottom end of the striking needle 11 protrudes out of the bottom end of the electron striking needle 12, and when the elastic connecting piece 13 resets, the bottom end of the electron striking needle 12 protrudes out of the bottom end of the striking needle 11, thus compressing the elastic connecting piece 13 to enable the bottom end of the electron striking needle 11 to protrude out of the connecting channel 20 to generate plasma, the bottom end of the striking needle 11 is prevented from being replaced by the elastic connecting piece 13, thereby avoiding the problem that the bottom end of the striking needle 11 is replaced by the striking needle 11, and the electric arc 11 is replaced, and the problem that the electric arc is replaced by the electric arc 11 is prevented from being blown out of the bottom end of the striking needle 11, and the bottom end of the striking needle 11 is replaced, the maintenance cost of the device is reduced, and the normal operation of the experiment is ensured.
Preferably, as shown in fig. 1, in this embodiment, the cascade assembly 3 includes a plurality of cascade plates 31 stacked sequentially from top to bottom, each cascade plate 31 is provided with a channel penetrating through the upper and lower surfaces thereof, and the channels are sequentially connected to form the cascade channel 30.
Preferably, as shown in fig. 1 and fig. 4, in order to facilitate the cooling of the cascade plates 31, the cascade assembly 3 further includes a plurality of cascade cooling pipes 32 having the same number as the cascade plates 31, cooling ports 310 are provided on the outer peripheral surface of each cascade plate 31, second cooling channels 311 are provided in each cascade plate, the cooling ports 310 are communicated with the second cooling channels 311, and each cascade cooling pipe 32 is connected to the cooling ports 310 in a one-to-one correspondence manner, so that each cascade plate 31 is individually cooled, the cooling efficiency is improved, and the individual replacement of the cascade plates 31 is facilitated.
Further, as shown in fig. 1, the bottom surface area of the arc striking needle 11 is smaller than the bottom surface area of the electron emission needle 12, and since the arc striking needle 11 plays a role of initiating the point discharge, the bottom surface area of the arc striking needle 11 should be as small as possible to help to achieve the point discharge, while the bottom surface area of the electron emission needle 12 is not required to be as small as the bottom surface area of the arc striking needle 11, and a larger bottom surface area can increase the electron emission degree and improve the density of the plasma source.
Further, as shown in fig. 1, the diameter of the bottom of the electron emission needle 12 gradually decreases from top to bottom, and by this structural design, the processing of the sliding channel 120 in the electron emission needle 12 is facilitated, the bottom end surface of the electron emission needle 12 is a plane perpendicular to the axis of the electron emission needle 12, and since the electron emission mainly occurs on the bottom end surface of the electron emission needle 12, the bottom end surface is a plane perpendicular to the axis of the electron emission needle 12, on one hand, the processing of the bottom end surface is facilitated, and on the other hand, the emission direction of electrons can be controlled more precisely, and the direction of the generated plasma can be controlled.
Further, as shown in fig. 1 and 2, a first cooling channel 121 is formed in the electron emission needle 12, the first cooling channel 121 is disposed around the sliding channel 120 and extends along the axial direction of the electron emission needle 12, two sides on the outer peripheral surface of the electron emission needle 12 are respectively provided with a cooling inlet 122 and a cooling outlet 123, the cooling inlet 122 and the cooling outlet 123 are respectively communicated with the first cooling channel 121, a coolant, such as common water, is introduced into the cooling channel 121 through the cooling inlet 122, and then flows out from the cooling outlet 123, so as to cool the electron emission needle 12, avoid overheating of the electron emission needle 12, and further ensure the normal operation of the cascade plasma generator 100.
Further, as shown in fig. 1, to realize the insulation connection between the electron emission needle 12 and the cathode base 2, the cathode assembly 1 further comprises an insulation tube 14, wherein the insulation tube 14 is sleeved on the periphery of the electron emission needle 12, and the insulation tube 14 is partially inserted into the connection channel 20, so that the electron emission needle 12 is insulated from the cathode base 2.
Preferably, in this embodiment, the insulating tube 14 is made of ceramic.
Further, as shown in fig. 1 and 2, the cascade plasma generator 100 further includes a locking assembly 5, the locking assembly 5 includes a sealing stud 51, a sealing nut 52 and a sealing ring 53, the sealing stud 51 is sleeved on the top of the outer periphery of the insulating tube 14, the bottom of the sealing stud 51 is connected to the connecting channel 20 in a sealing manner, a threaded portion is provided on the outer periphery of the sealing stud 51, the sealing ring 53 is sleeved on the electron emission needle 12, the sealing nut 52 has a sealing cavity 520, an opening 521 communicated with the sealing cavity is provided on the top of the sealing nut 52, the sealing nut 52 is sleeved on the electron emission needle 12 and is screwed with the sealing stud 51, and the sealing ring 53 is pressed between the sealing stud 51 and the electron emission needle 12, so that the electron emission needle 12 and the cathode seat 2 are connected in a sealing manner.
Preferably, as shown in fig. 1 and 2, the connecting channel 20 includes a sealing portion 201 and a connecting portion 202 sequentially arranged from top to bottom, the diameter of the sealing portion 201 is larger than that of the connecting portion 202, and the bottom of the sealing stud 51 is connected to the sealing portion 201 in a sealing manner, so as to facilitate the installation, connection and positioning of the sealing stud 51.
Further, as shown in fig. 1 and 2, the locking assembly 5 further includes an insulating pad 54, the insulating pad 54 includes a sleeve portion 541 and a pressing portion 542, the sleeve portion 541 is sleeved on the outer periphery of the electron emission needle 12, the pressing portion 542 is annularly disposed on the outer periphery of the sleeve portion 541 and extends outwards in a radial direction, the outer peripheral surface of the sleeve portion 541 is tightly attached to the inner wall of the opening 521, the diameter of the pressing portion 542 is larger than that of the opening 521, and the bottom surface of the pressing portion 542 is tightly attached to the top surface of the sealing ring 53, so that when the sealing nut 52 is screwed tightly with the sealing stud 51, the pressing portion 542 presses the sealing ring 53, and further presses the sealing ring 53 between the sealing stud 51 and the electron emission needle 12.
Further, as shown in fig. 1 and 2, the top opening of the sealing stud 51 has a tapered surface with a gradually decreasing outer diameter from top to bottom, and the outer circumference of the sealing ring 53 is a tapered surface that is matched and connected with the top opening of the sealing stud, so that when the sealing nut 52 is screwed and screwed with the sealing stud 51, the sealing ring 53 is pressed between the sealing stud 51 and the electron emission needle 12, so as to ensure the reliability of the sealing connection between the electron emission needle 12 and the cathode seat 2.
Further, the sealing stud 51 and the sealing nut 52 are made of different materials, in this embodiment, the sealing stud 51 is made of stainless steel, the sealing nut 52 is made of brass, and the screw thread made of different materials does not have a "seizing" phenomenon when being screwed down, so as to facilitate subsequent disassembly and maintenance.
Further, as shown in fig. 1 and 3, the elastic connection member 13 includes a bellows 131 and a bellows flange 132 fixedly disposed on the top of the bellows 131, the bellows flange 132 is fixedly connected with the top of the arc striking needle 11, the arc striking needle 11 is inserted into the bellows 131, the bellows 131 is hermetically connected to the top of the electron emission needle 12, and elastic connection between the arc striking needle 11 and the electron emission needle 12 is achieved through the bellows 131.
The working process of the invention is that the corrugated tube 131 is compressed, the bottom end of the arc striking needle 11 protrudes out of the bottom end of the electron emission needle 12, the arc striking needle 11 and the anode 4 are electrified, a potential difference is formed between the arc striking needle 11 and the anode 4, the tip of the arc striking needle 11 causes the tip discharge, thereby ionizing the working gas entering from the gas channel 21 and then forming plasma, after stable plasma is formed, the corrugated tube 131 is released to automatically reset, the bottom end of the electron emission needle 12 protrudes out of the bottom end of the arc striking needle 11, electrons are continuously emitted by the front end of the electron emission needle 12 to continuously provide stable plasma, and compared with the bottom end surface area of the arc striking needle 11, the bottom end surface area of the electron emission needle 12 is larger, the electron emission degree can be increased, and the density of the plasma is improved.
In summary, embodiments of the present invention provide a cascade plasma generator 100, which includes a cathode assembly 1, a cathode base 2, a cascade assembly 3, and an anode 4; the cathode assembly 1 comprises an arc striking needle 11, an electron emission needle 12 and an elastic connecting piece 13, wherein the cathode assembly 1 is installed through a cathode seat 2, a cascade plasma generator 100 is formed by the cathode assembly 1, the cascade assembly 3 and an anode 4, high voltage is applied between the cathode assembly 1 and the anode 4, tip discharge is realized through sliding the arc striking needle 11 penetrating through the electron emission needle 12, thereby working gas introduced from the gas channel 21 is broken down to generate an electric arc, the working gas is ionized to generate plasma, the plasma starts from the connecting channel 20 and is emitted to the outside of the cascade plasma generator 100 through the cascade channel 30 and the emission channel 40, the bottom end of the arc striking needle 11 protrudes from the bottom end of the electron emission needle 12 when the elastic connecting piece 13 is compressed, and when the elastic connecting piece 13 is reset, the bottom end of the electron emission needle 12 protrudes from the bottom end of the arc striking needle 11, therefore, when the cascade plasma generator 100 is started, the elastic connecting piece 13 is compressed, the bottom end of the electron emission needle 11 protrudes from the bottom end of the arc striking needle 11, the bottom end of the electron emission needle 12 is enabled to be retracted, and the electron emission needle 11 protrudes from the bottom end of the arc striking needle 11 when the arc 11 is reset, thereby the bottom end of the arc is enabled to be in the bottom by the elastic connecting piece 12, and then avoid striking needle 11 to be in the cavity that gas takes place the ionization always, then make the needle point of striking needle 11 can not take place a large amount of impurity and pile up and the problem that the needle point melts to reduce striking needle 11's change frequency, reduce device maintenance cost and ensure the normal clear of experiment.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and substitutions can be made by those skilled in the art without departing from the technical principles of the present invention, and these modifications and substitutions should also be considered as being within the scope of the present invention.